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• 151.
Laboratory of Stem Cells and Neurogeneration, Institute of Anatomy, Histology and Pathology, Facultu of Medicine and Center for INterdiciplinary Studies on the Nervous System (CISNe), Universitad Austral de Chile; Institute for Molecular Regenerative MEdicine and Spinal Cord Injury and Tissue Regeneration Center Salzburg (SCI-TReCS), Paracelsus University, Salzburg, Austira. Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
Bisphenol-A and metabolic diseases: epigenetic developmental and transgenerational basis2016In: Environmental Epigenetics, ISSN 2058-5888, Vol. 2, no 3, p. 1-10Article in journal (Refereed)

Exposure to environmental toxicants is now accepted as a factor contributing to the increasing incidence of obesity and metabolic diseases around the world. Such environmental compounds are known as ‘obesogens’. Among them, bisphenol-A (BPA) is the most widespread and ubiquitous compound affecting humans and animals. Laboratory animal work has provided conclusive evidence that early-life exposure to BPA is particularly effective in predisposing individuals to weight gain. Embryonic exposure to BPA is reported to generate metabolic disturbances later in life, such as obesity and diabetes. When BPA administration is combined with a high-fat diet, there is an exacerbation in the development of metabolic disorders. Remarkably, upon BPA exposure of gestating females, metabolic disturbances have been found both in the offspring and later in life in the mothers themselves. When considering the metabolic effects generated by an early developmental exposure to BPA, one of the questions that arises is the role of precursor cells in the etiology of metabolic disorders. Current evidence shows that BPA and other endocrine disruptors have the ability to alter fat tissue development and growth by affecting the capacity to generate functional adipocytes, as well as their rate of differentiation to specific cell types. Epigenetic mechanisms seem to be involved in the BPA-induced effects related to obesity, as they have been described in both in vitro and in vivo models. Moreover, recent reports also show that developmental exposure to BPA generates abnormalities that can be transmitted to future generations, in a process called as transgenerational epigenetic inheritance.

• 152.
King Saud University, Saudi Arabia .
King Saud University, Saudi Arabia; National Institute of Laser and Optronics, Nilore, Islamabad, Pakistan. King Saud University, Saudi Arabia . Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology. King Saud University, Riyadh, Saudi Arabia.
Growth and characterization of ZnO nanowires for optical applications2013In: Laser physics, ISSN 1054-660X, E-ISSN 1555-6611, Vol. 23, no 6, article id 065602Article in journal (Refereed)

In the present work, cerium oxide CeO2 nanoparticles were synthesized by the sol-gel method and used for the growth of ZnO nanorods. The synthesized nanoparticles were studied by x-ray diffraction (XRD) and Raman spectroscopic techniques. Furthermore, these nanoparticles were used as the seed layer for the growth of ZnO nanorods by following the hydrothermal growth method. The structural study of ZnO nanorods was carried out by means of field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and XRD techniques. This study demonstrated that the grown ZnO nanorods are well aligned, uniform, of good crystal quality and have diameters of less than 200 nm. Energy dispersive x-ray (EDX) analysis revealed that the ZnO nanorods are composed only of zinc, cerium as the seed atom, and oxygen atoms, with no other impurities in the grown nanorods. Moreover, a photoluminescence (PL) approach was applied for the optical characterization, and it was observed that the near-band-edge (NBE) emission was the same as that of the zinc acetate seed layer, however the green and orange/red emission peaks were slightly raised due to possibly higher levels of defects in the cerium oxide seeded ZnO nanorods. This study provides an alternative approach for the controlled synthesis of ZnO nanorods using cerium oxide nanoparticles as the seed nucleation layer, improving both the morphology of the nanorods and the performance of devices based upon them.

• 153.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
A continuous-time dynamical system that can sort agents through distributed protocols2014In: 2014 IEEEMulti-conference on Systems and Control, Antibes, France: Institute of Electrical and Electronics Engineers (IEEE), 2014, p. 2153-2158Conference paper (Refereed)

A class of continuous-time dynamical systems able to sort a list of real numbers is introduced in this paper. The dynamical sorting is achieved in a completely distributed manner, by modifying a consensus problem, namely right multiplying a Laplacian matrix by a diagonal matrix of weights that represents the desired order. The sorting obtained is relative, i.e., a conservation law is imposed on the dynamics. It is shown that sorting can be achieved in finite-time even in a globally smooth way.

• 154.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Involutive flows and discretization errors for nonlinear driftless control systems2017In: Systems & control letters (Print), ISSN 0167-6911, E-ISSN 1872-7956, Vol. 110, p. 29-37Article in journal (Refereed)

In a continuous-time nonlinear driftless control system, an involutive flow is a composition of input profiles that does not excite any Lie bracket. Such flow composition is trivial, as it corresponds to a "forth and back" cyclic motion obtained rewinding the system along the same path. The aim of this paper is to show that, on the contrary, when a (nonexact) discretization of the nonlinear driftless control system is steered along the same trivial input path, it produces a net motion, which is related to the gap between the discretization used and the exact discretization given by a Taylor expansion. These violations of involutivity can be used to provide an estimate of the local truncation error of numerical integration schemes. In the special case in which the state of the driftless control system admits a splitting into shape and phase variables, our result corresponds to saying that the geometric phases of the discretization need not obey an area rule, i.e., even zero-area cycles in shape space can lead to nontrivial geometric phases. (C) 2017 Elsevier B.V. All rights reserved.

The full text will be freely available from 2019-11-04 12:15
• 155.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Minimal eventually positive realizations of externally positive systems2016In: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 68, p. 140-147Article in journal (Refereed)

It is a well-known fact that externally positive linear systems may fail to have a minimal positive realization. In order to investigate these cases, we introduce the notion of minimal eventually positive realization, for which the state update matrix becomes positive after a certain power. Eventually positive realizations capture the idea that in the impulse response of an externally positive system the state of a minimal realization may fail to be positive, but only transiently. As a consequence, we show that in discrete-time it is possible to use downsampling to obtain minimal positive realizations matching decimated sequences of Markov coefficients of the impulse response. In continuous-time, instead, if the sampling time is chosen sufficiently long, a minimal eventually positive realization leads always to a sampled realization which is minimal and positive.

• 156.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Nonintegrable discrete-time driftless control systems: geometric phases beyond the area rule2016In: 2016 IEEE 55th Conference on Decision and Control (CDC), IEEE Press, 2016, p. 4692-4697Conference paper (Refereed)

In a continuous-time nonlinear driftless control system, a geometric phase is a consequence of nonintegrability of the vector fields, and it describes how cyclic trajectories in shape space induce non-periodic motion in phase space, according to an area rule. The aim of this paper is to shown that geometric phases exist also for discrete-time driftless nonlinear control systems, but that unlike their continuous-time counterpart, they need not obey any area rule, i.e., even zero-area cycles in shape space can lead to nontrivial geometric phases. When the discrete-time system is obtained through Euler discretization of a continuous-time system, it is shown that the zero-area geometric phase corresponds to the gap between the Euler discretization and an exact discretization of the continuous-time system.

• 157.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
Representing externally positive systems through minimal eventually positive realizations2015In: Proceedings of the IEEE 54th Annual Conference on Decision and Control (CDC),, Institute of Electrical and Electronics Engineers (IEEE), 2015, p. 6385-6390Conference paper (Refereed)

In order to investigate the cases in which an externally positive discrete-time system fails to have a minimal positive realization, in this paper we introduce the notion of minimal eventually positive realization, fr which the state update matrix becomes positive after a certain power. This property captures the idea that in the impulse response of an externally positive system the state of a minimal realization may fail to be positive, but only transiently. It is shown in the paper that whenever a minimal eventually positive realization exists, then the sequence of Markov parameters of the impulse response admits decimated subsequences for which minimal positive realizations exist and can be obtained by downsampling the eventually positive realization.

• 158.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
The Geometric Phase of Stock Trading2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 8, p. e0161538-Article in journal (Refereed)

Geometric phases describe how in a continuous-time dynamical system the displacement of a variable (called phase variable) can be related to other variables (shape variables) undergoing a cyclic motion, according to an area rule. The aim of this paper is to show that geometric phases can exist also for discrete-time systems, and even when the cycles in shape space have zero area. A context in which this principle can be applied is stock trading. A zero-area cycle in shape space represents the type of trading operations normally carried out by high-frequency traders (entering and exiting a position on a fast time-scale), while the phase variable represents the cash balance of a trader. Under the assumption that trading impacts stock prices, even zero-area cyclic trading operations can induce geometric phases, i.e., profits or losses, without affecting the stock quote.

• 159.
Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, Faculty of Science & Engineering.
John Innes Centre, England.
Metabolic Adaptation Processes That Converge to Optimal Biomass Flux Distributions2015In: PloS Computational Biology, ISSN 1553-734X, E-ISSN 1553-7358, Vol. 11, no 9, article id e1004434Article in journal (Refereed)

In simple organisms like E. coli, the metabolic response to an external perturbation passes through a transient phase in which the activation of a number of latent pathways can guarantee survival at the expenses of growth. Growth is gradually recovered as the organism adapts to the new condition. This adaptation can be modeled as a process of repeated metabolic adjustments obtained through the resilencings of the non-essential metabolic reactions, using growth rate as selection probability for the phenotypes obtained. The resulting metabolic adaptation process tends naturally to steer the metabolic fluxes towards high growth phenotypes. Quite remarkably, when applied to the central carbon metabolism of E. coli, it follows that nearly all flux distributions converge to the flux vector representing optimal growth, i.e., the solution of the biomass optimization problem turns out to be the dominant attractor of the metabolic adaptation process.

• 160.
Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
Ecophysiology methods: Refining the old, validating the new and developing for the future2016In: Comparative Biochemistry and Physiology A, ISSN 1095-6433, E-ISSN 1531-4332, Vol. 202Article in journal (Other academic)

n/a

• 161.
Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. University of Mayor San Andres, Bolivia. Tinamou Chile SL, Chile. University of Mayor San Andres, Bolivia.
Aerobic performance in tinamous is limited by their small heart. A novel hypothesis in the evolution of avian flight2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 15964Article in journal (Refereed)

Some biomechanical studies from fossil specimens suggest that sustained flapping flight of birds could have appeared in their Mesozoic ancestors. We challenge this idea because a suitable musculoskeletal anatomy is not the only requirement for sustained flapping flight. We propose the "heart to fly" hypothesis that states that sustained flapping flight in modern birds required an enlargement of the heart for the aerobic performance of the flight muscles and test it experimentally by studying tinamous, the living birds with the smallest hearts. The small ventricular size of tinamous reduces cardiac output without limiting perfusion pressures, but when challenged to fly, the heart is unable to support aerobic metabolism (quick exhaustion, larger lactates and post-exercise oxygen consumption and compromised thermoregulation). At the same time, cardiac growth shows a crocodilian-like pattern and is correlated with differential gene expression in MAPK kinases. We integrate this physiological evidence in a new evolutionary scenario in which the ground-up, short and not sustained flapping flight displayed by tinamous represents an intermediate step in the evolution of the aerobic sustained flapping flight of modern birds.

• 162.
Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
A study on emerging electronics for systems accepting soft errors2016Licentiate thesis, monograph (Other academic)

Moore’s law has until today mostly relied on shrinkage of the size of the devices inintegrated circuits. However, soon the granularity of the atoms will set a limit together with increased error probability of the devices. How can Moore’s law continue in thefuture? To overcome the increased error rate, we need to introduce redundancy. Applyingmethods from biology may be a way forward, using some of the strategies that transformsan egg into a fetus, but with electronic cells.

A redundant system is less sensitive to failing components. We define electronic clayas a massive redundancy system of interchangeable and unified subsystems. We show how a mean voter, which is simpler than a majority voter, impact a redundant systemand how optimization can be formalized to minimize the impact of failing subsystems.The performance at given yield can be estimated with a first order model, without the need for Monte-Carlo simulations. The methods are applied and verified on a redundant finite-impulse response filter.

The elementary circuit behavior of the memristor, ”the missing circuit element”, is investigated for fundamental understanding and how it can be used in applications. Different available simulation models are presented and the linear drift model is simulated with Joglekar-Wolf and Biolek window functions. Driven by a sinusoidal current, the memristor is a frequency dependent component with a cut-off frequency. The memristor can be densely packed and used in structures that both stores and compute in the same circuit, as neurons do. Surrounding circuit has to affect (write) and react (read) to the memristor with the same two terminals.

We looked at artificial neural network for pattern recognition, but also for self organization in electronic cell array. Finally we look at wireless sensor network and how such system can adopt to the environment. This is also a massive redundant clay-like system.

Future electronic systems will be massively redundant and adaptive. Moore’s law will continue, not based on shrinking device sizes, but on cheaper, numerous, unified and interchangeable subsystems.

• 163.
Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Electrical Engineering, Integrated Circuits and Systems. Linköping University, Faculty of Science & Engineering.
Transfer Characteristics and Bandwidth Limitation in a Linear-Drift Memristor Model2015In: 2015 EUROPEAN CONFERENCE ON CIRCUIT THEORY AND DESIGN (ECCTD), IEEE , 2015, p. 332-335Conference paper (Refereed)

The linear-drift memristor model, suggested by HP Labs a few years ago, is used in this work together with two window functions. From the equations describing the memristor model, the transfer characteristics of a memristor is formulated and analyzed. A first-order estimation of the cut-off frequency is shown, that illustrates the bandwidth limitation of the memristor and how it varies with some of its physical parameters. The design space is elaborated upon and it is shown that the state speed, the variation of the doped and undoped regions of the memristor, is inversely proportional to the physical length, and depth of the device. The transfer characteristics is simulated for Joglekar-Wolf, and Biolek window functions and the results are analyzed. The Joglekar-Wolf window function causes a distinct behavior in the tranfer characteristics at cut-off frequency. The Biolek window function on the other hand gives a smooth state transfer function, at the cost of loosing the one-to-one mapping between charge and state. We also elaborate on the design constraints derived from the transfer characteristics.

• 164.
Princeton University, NJ 08544 USA.
Linköping University, Department of Electrical Engineering, Communication Systems. Linköping University, Faculty of Science & Engineering. Princeton University, NJ 08544 USA.
Wireless Information and Power Transfer in Multiway Massive MIMO Relay Networks2016In: IEEE Transactions on Wireless Communications, ISSN 1536-1276, E-ISSN 1558-2248, Vol. 15, no 6, p. 3837-3855Article in journal (Refereed)

Simultaneous wireless information and power transfer techniques for multiway massive multiple-input multiple-output (MIMO) relay networks are investigated. By using two practically viable relay receiver designs, namely 1) the power splitting receiver and 2) the time switching receiver, asymptotic signal-to-interference-plus-noise ratio (SINR) expressions are derived for an unlimited number of antennas at the relay. These asymptotic SINRs are then used to derive asymptotic symmetric sum rate expressions in closed form. Notably, these asymptotic SINRs and sum rates become independent of radio frequency-to-direct current (RF-to-DC) conversion efficiency in the limit of infinitely many relay antennas. Moreover, tight average sum rate approximations are derived in closed form for finitely many relay antennas. The fundamental tradeoff between the harvested energy and the sum rate is quantified for both relay receiver structures. Notably, the detrimental impact of imperfect channel state information (CSI) on the MIMO detector/precoder is investigated, and thereby, the performance degradation caused by pilot contamination, which is the residual interference due to nonorthogonal pilot sequence usage in adjacent/cochannel systems, is quantified. The presence of cochannel interference (CCI) can be exploited to be beneficial for energy harvesting at the relay, and consequently, the asymptotic harvested energy is an increasing function of the number of cochannel interferers. Notably, in the genie-aided perfect CSI case, the detrimental impact of CCI for signal decoding can be cancelled completely whenever the number of relay antennas grows without bound. Nevertheless, the pilot contamination severely degrades the sum rate performance even for infinitely many relay antennas.

• 165.
Linköping University, Department of Electrical Engineering. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Electrical Engineering, Electronics System. Linköping University, The Institute of Technology. Boadilla del Monte, Madrid, Spain. Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Electrical Engineering, Information Coding. Linköping University, Faculty of Science & Engineering.
New Radix-2 and Radix-22 Constant Geometry Fast Fourier Transform Algorithms For GPUs2013Conference paper (Refereed)

This paper presents new radix-2 and radix-22 constant geometry fast Fourier transform (FFT) algorithms for graphics processing units (GPUs). The algorithms combine the use of constant geometry with special scheduling of operations and distribution among the cores. Performance tests on current GPUs show a significant improvements compared to the most recent version of NVIDIA’s well-known CUFFT, achieving speedups of up to 5.6x.

• 166.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Analysis, Design, and Optimization of Embedded Control Systems2016Doctoral thesis, monograph (Other academic)

Today, many embedded or cyber-physical systems, e.g., in the automotive domain, comprise several control applications, sharing the same platform. It is well known that such resource sharing leads to complex temporal behaviors that degrades the quality of control, and more importantly, may even jeopardize stability in the worst case, if not properly taken into account.

In this thesis, we consider embedded control or cyber-physical systems, where several control applications share the same processing unit. The focus is on the control-scheduling co-design problem, where the controller and scheduling parameters are jointly optimized. The fundamental difference between control applications and traditional embedded applications motivates the need for novel methodologies for the design and optimization of embedded control systems. This thesis is one more step towards correct design and optimization of embedded control systems.

Offline and online methodologies for embedded control systems are covered in this thesis. The importance of considering both the expected control performance and stability is discussed and a control-scheduling co-design methodology is proposed to optimize control performance while guaranteeing stability. Orthogonal to this, bandwidth-efficient stabilizing control servers are proposed, which support compositionality, isolation, and resource-efficiency in design and co-design. Finally, we extend the scope of the proposed approach to non-periodic control schemes and address the challenges in sharing the platform with self-triggered controllers. In addition to offline methodologies, a novel online scheduling policy to stabilize control applications is proposed.

• 167.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Self-Triggered Controllers, Resource Sharing, and Hard Guarantees2016In: 2016 2ND INTERNATIONAL CONFERENCE ON EVENT-BASED CONTROL, COMMUNICATION, AND SIGNAL PROCESSING (EBCCSP), IEEE , 2016Conference paper (Refereed)

Today, many control applications in embedded and cyber-physical systems are implemented on shared platforms, alongside other hard real-time or safety-critical applications. Having the resource shared among several applications, to provide hard guarantees, it is required to identify the amount of resource needed for each application. This is rather straightforward when the platform is shared among periodic control and periodic real-time applications. In the case of event-triggered and self-triggered controllers, however, the execution patterns and, in turn, the resource usage are not clear. Therefore, a major implementation challenge, when the platform is shared with self-triggered controllers, is to provide hard and efficient stability and schedulability guarantees for other applications. In this paper, we identify certain execution patterns for self-triggered controllers, using which we are able to provide hard and efficient stability guarantees for periodic control applications.

• 168.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Scuola Super Sant Anna, Italy. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Analysis and Design of Real-Time Servers for Control Applications2016In: I.E.E.E. transactions on computers (Print), ISSN 0018-9340, E-ISSN 1557-9956, Vol. 65, no 3, p. 834-846Article in journal (Refereed)

Today, a considerable portion of embedded systems, e.g., automotive and avionic, comprise several control applications. Guaranteeing the stability of these control applications in embedded systems, or cyber-physical systems, is perhaps the most fundamental requirement while implementing such applications. This is different from the classical hard real-time systems where often the acceptance criterion is meeting the deadline. In other words, in the case of control applications, guaranteeing stability is considered to be a main design goal, which is linked to the amount of delay and jitter a control application can tolerate before instability. This advocates the need for new design and analysis techniques for embedded real-time systems running control applications. In this paper, the analysis and design of such systems considering a server-based resource reservation mechanism are addressed. The benefits of employing servers are manifold: providing a compositional and scalable framework, protection against other tasks misbehaviors, and systematic bandwidth assignment and co-design. We propose a methodology for designing bandwidth-optimal servers to stabilize control tasks. The pessimism involved in the proposed methodology is both discussed theoretically and evaluated experimentally.

• 169.
Linköping University, Department of Computer and Information Science, ESLAB - Embedded Systems Laboratory. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, ESLAB - Embedded Systems Laboratory. Linköping University, Department of Computer and Information Science, ESLAB - Embedded Systems Laboratory. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, The Institute of Technology.
Jfair: A Scheduling Algorithm to Stabilize Control Applications2015In: 21st IEEE Real-Time and Embedded Technology and Applications Symposium, Cyber-Physical Systems Week, Seattle, WA, April 2015, IEEE Computer Society, 2015, p. 63-72Conference paper (Refereed)

Control applications are considered to be among the core applications in cyber-physical and embedded realtime systems, for which jitter is typically an important factor. This paper investigates whether it is possible to guarantee certain amount of jitter for a given set of applications on a shared platform. The effect of jitter on the stability of control applications and its relation with the latency will be discussed. The importance arises from the fact that it is considerably easier to manage the constant part of the delay (known as latency), while the process of coping with the varying part of the delay (known as jitter) is more involved. The proposed solution guarantees certain jitter limits, and at the same time does not lead to overly pessimistic latency values. The results are later used in a design optimization problem to minimize the resource utilized.

• 170.
Embedded Systems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland..
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Optimization of Message Encryption for Real-Time Applications in Embedded Systems2017In: IEEE Transactions on Computers, ISSN 0018-9340Article in journal (Refereed)

Today, security can no longer be treated as a secondary issue in embedded and cyber-physical systems. Therefore, one of the main challenges in these domains is the design of secure embedded systems under stringent resource constraints and real-time requirements. However, there exists an inherent trade-off between the security protection provided and the amount of resources allocated for this purpose. That is, the more the amount of resources used for security, the higher the security, but the fewer the number of applications which can be run on the platform and meet their timing requirements. This trade-off is of high importance since embedded systems are often highly resource constrained. In this paper, we propose an efficient solution to maximize confidentiality, while also guaranteeing the timing requirements of real-time applications on shared platforms.

• 171.
Embedded Systems Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Switzerland..
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Department of Automatic Control, Lund University, Sweden. Department of Automatic Control, Lund University, Sweden.
Control-Quality Driven Design of Embedded Control Systems with Stability Guarantees2017In: IEEE design & test, ISSN 2168-2356, E-ISSN 2168-2364Article in journal (Refereed)

Today, the majority of control applications in embedded systems, e.g., in the automotive domain, are implemented as software tasks on shared platforms. Ignoring implementation impacts during the design of embedded control systems results in complex timing behaviors that may lead to poor performance and, in the worst case, instability of control applications. This article presents a methodology for implementation-aware design of high-quality and stable embedded control systems on shared platforms with complex timing behaviors.

• 172.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
University of California at Los Angeles, USA. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Self-Triggered Controllers and Hard Real-Time Guarantees2016In: PROCEEDINGS OF THE 2016 DESIGN, AUTOMATION & TEST IN EUROPE CONFERENCE & EXHIBITION (DATE), Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 636-641Conference paper (Refereed)

It is well known that event-triggered and self-triggered controllers implemented on dedicated platforms can provide the same performance as the traditional periodic controllers, while consuming considerably less bandwidth. However, since the majority of controllers are implemented by software tasks on shared platforms, on one hand, it might no longer be possible to grant access to the event-triggered controller upon request. On the other hand, due to the seemingly irregular requests from self-triggered controllers, other applications, while in reality schedulable, may be declared unschedulable, if not carefully analyzed. The schedulability and response-time analysis in the presence of self-triggered controllers is still an open problem and the topic of this paper.

• 173.
Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. University of Gavle, Sweden.
University of Gävle, Sweden.
Increased cogeneration of renewable electricity through energy cooperation in a Swedish district heating system - A case study2018In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 116, p. 866-877Article in journal (Refereed)

The present study of the district heating (DH) system in the city of Kisa, Sweden, shows how, through energy cooperation with a nearby sawmill and paper mill, a local energy company contributes to energy efficient DH and cost-effective utilization of a new biofuel combined heat and power (CHP) plant. Cases of stand-alone and integrated energy systems are optimized with the linear program MODEST. The European power market is assumed to be fully deregulated. The results show clear advantages for the energy company to cooperate with these industries to produce heat for DH and process steam for industry. The cooperating industries gain advantages from heat and/or biofuel by-product supply as well. The opening to use a biofuel CHP plant for combined heat supply results in cogenerated electricity of almost 29 GWh/a with an increased biofuel use of 13 GWhia, zero fuel oil use and CO2 emission reductions of 25,800 tons CO2/a with coal-condensing power plant on the margin and biofuel as limited resource. The total system cost decreases by -2.18 MEUR/a through extended cooperation and renewable electricity sales. The sensitivity analysis shows that the profitability of investing in a biofuel CHP plant increases with higher electricity and electricity certificate prices. (C) 2017 Elsevier Ltd. All rights reserved.

• 174.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
An Evaluation of Clustering and Classification Algorithms in Life-Logging Devices2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Using life-logging devices and wearables is a growing trend in today’s society. These yield vast amounts of information, data that is not directly overseeable or graspable at a glance due to its size. Gathering a qualitative, comprehensible overview over this quantitative information is essential for life-logging services to serve its purpose.

This thesis provides an overview comparison of CLARANS, DBSCAN and SLINK, representing different branches of clustering algorithm types, as tools for activity detection in geo-spatial data sets. These activities are then classified using a simple model with model parameters learned via Bayesian inference, as a demonstration of a different branch of clustering.

Results are provided using Silhouettes as evaluation for geo-spatial clustering and a user study for the end classification. The results are promising as an outline for a framework of classification and activity detection, and shed lights on various pitfalls that might be encountered during implementation of such service.

• 175.
Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology. Department of Physics, Faculty of Science, Thaksin University, 93110 Phattalung, Thailand .
Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, Faculty of Science & Engineering. Applied Semiconductor Physics, Department of Microtechnology and Nanoscience, Chalmers University of Technology, S‐41296 Göteborg, Sweden. Applied Semiconductor Physics, Department of Microtechnology and Nanoscience, Chalmers University of Technology, S‐41296 Göteborg, Sweden. Linköping University, Department of Physics, Chemistry and Biology, Semiconductor Materials. Linköping University, Faculty of Science & Engineering.
Polarized Emission from Single GaN Quantum Dots Grown by Molecular Beam Epitaxy2011Conference paper (Other academic)

Polarization resolved microphotoluminescence measurements of single MBE‐grown GaN/Al(Ga)N quantum dots (QDs) have been performed. The exciton and biexciton peaks with full width at half maximum as narrow as <500 μeV  were observed. Interestingly, there exist both positive and negative binding energies of the biexciton, explained in term of different sizes of the measured dots, resulting in different built‐in electric field. Moreover, a strongly linearly polarized emission is observed for the investigated dots with a degree of linear polarization of about 0.9, interpreted as the valence‐band mixing induced by in‐plane anisotropy due to strain and/or QD shape.

• 176.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Biogas Research Center. Linköping University, Faculty of Science & Engineering. Linköping University, Biogas Research Center (BRC).
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Biogas Research Center. Linköping University, Faculty of Science & Engineering. Division of Energy Processes, Department of Chemical Engineering and Technology, Royal Institute of Technology, Stockholm, Sweden. Division of Energy Processes, Department of Chemical Engineering and Technology, Royal Institute of Technology, Stockholm, Sweden. Department of Industrial Economics and Management, Royal Institute of Technology, Stockholm, Sweden.
Biogas in the transport sector: Actor and policy analysis focusing on the demand side in the Stockholm region2018In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 129, p. 70-80Article in journal (Refereed)

Sweden has ambitions to phase out fossil fuels and significantly increase the share of biofuels it uses. This articlefocuses on Stockholm County and biogas, with the aim to increase the knowledge about regional preconditions.Biogas-related actors have been interviewed, focusing on the demand side. Biogas solutions play an essentialrole, especially regarding bus transports and taxis. Long-term development has created well-functioning sociotechnicalsystems involving collaboration. However, uncertainties about demand and policy cause hesitation andsigns of stagnating development.Public organizations are key actors regarding renewables. For example, Stockholm Public Transport procuresbiogas matching the production at municipal wastewater treatment plants, the state-owned company Swedaviasteers via a queuing system for taxis, and the municipalities have shifted to “environmental cars”.There is a large interest in electric vehicles, which is expected to increase significantly, partially due tosuggested national policy support. The future role of biogas will be affected by how such an expansion comesabout. There might be a risk of electricity replacing biogas, making it more challenging to reach a fossil-freevehicle fleet. Policy issues strongly influence the development. The environmental car definition is of importance,but its limited focus fails to account for several different types of relevant effects. The dynamic policylandscape with uncertainties about decision makers’ views on biogas seems to be one important reason behindthe decreased pace of development. A national, long-term strategy is missing. Both the European Union andSweden have high ambitions regarding a bio-based and circular economy, which should favor biogas solutions.

The full text will be freely available from 2019-10-20 10:58
• 177.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering. Linköping University, Biogas Research Center.
Den Kgl. Veterinær- og Landbohøjskole, Denmark. Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering. Linköping University, Biogas Research Center.
Systematic assessment of feedstock for an expanded biogas production: A multi-criteria approach2017Report (Other academic)

Biogas solutions can contribute to more renewable and local energy systems, and also involve other essential aspects such as nutrient recycling. From a theoretical feedstock perspective there is a great biogas potential in Sweden, but the development has been relatively slow as many biogas producers face challenges of different types. Among the many influencing factors, the choice of feedstocks (biomass) is of strategic importance. Within the Biogas Research Center (BRC), hosted by Linköping University in Sweden, a research project focused on feedstock has been ongoing for several years. It has involved researchers, biogas and biofertilizer producers, agricultural organizations and others. The main aim has been to develop a method to assess the suitability of feedstock for biogas and biofertilizer production, and to apply this method on a few selected feedstocks. A multi-criteria method has been developed that covers potential, feasibility and resource efficiency, operationalized via 17 indicators directed towards cost efficiency, technological feasibility, energy and environmental performance, accessibility, competition, policy and other issues. Thus the method it is relatively comprehensive, yet hopefully simple enough to be used by practitioners.

The main ambition, applying the method, has been to collect and structure relevant information to facilitate strategic overviews, communication and informed decision making. This is relevant for development within the biogas and biofertilizer industry, for policymakers, to define and prioritize among essential research projects, etc. This report presents some essential parts of this project, focusing on the multi-criteria method and results regarding ley crops, straw, farmed blue mussels and food waste (and stickleback to some extent). It clarifies how the method can be applied and highlights barriers, drivers and opportunities for each feedstock. Comparisons are also made. The results indicate that biogas production from food waste and ley crops is the most straightforward, and for straw and farmed blue mussels there are more obstacles to overcome. For all of them, the dynamic and very uncertain policy landscape is a barrier. In the final chapter, some conclusions about the method and its application are drawn.

• 178.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Assessment of Feedstocks for Biogas Production, Part II: Results for Strategic Decision Making2017In: Resources, Conservation and Recycling, ISSN 0921-3449, E-ISSN 1879-0658, Vol. 122, p. 388-404Article in journal (Refereed)

Biogas production is essentially based on organic materials and biological processes; hence it can contribute to the transition toward a biobased economy. Biogas is a biofuel that can contribute to a more renewable and local energy system. In comparison with other biofuels, biogas is more flexible and can be produced from many different types of feedstock, including biomass containing various shares of carbohydrates, lipids and, both from primary and secondary raw materials. However, a significantly expanded biogas production is dependent on good business conditions, in turn related to societal acceptance and support. There are many factors that can make a biogas solution more or less suitable for both producers and the broader society. Among the many influencing factors, the choice of feedstocks (biomass) for producing biogas and biofertilizer is of strategic importance. But, to assess the suitability is complicated, because it is linked to many different challenges such as cost, energy balance, environmental impacts, institutional conditions, available technologies, geographical conditions, alternative and competing interest, and so on. Suitability includes aspects related to feasibility for implementation, potential for renewable energy and nutrient recycling, and resource efficiency. In this article, a multi-criteria framework, which is proposed in a companion article (Part II), is used to assess the suitability of four types of feedstocks for producing biogas (considering Swedish conditions). The assessed feedstocks are ley crops, straw, farmed blue mussels, and source-sorted food waste. The results have synthesized and structured a lot of information, which facilitates considerably for those that want an overview and to be able to review several different areas simultaneously. Among the assessed feedstocks, biogas production from household food waste and ley is the most straightforward. For straw and farmed blue mussels, there are more obstacles to overcome including some significant barriers. For all feedstock there are challenges related to the institutional conditions. The assessment contributes to the knowledge about sustainable use of these feedstocks, and the limitations and opportunities for biogas development. It supports more informed decision making, both in industry and policy. Existing, or forthcoming, biogas and biofertilizer producers who are considering altering or expanding their production systems can benefit from a better understanding of different choices of feedstock that are or can be (potentially) at their disposal; thus, identify hotspots, weak points, and possible candidates for implementation in future. This research is performed within the Biogas Research Center (BRC), which is a transdisciplinary center of excellence with the overall goal of promoting resource-efficient biogas solutions in Sweden. The BRC is funded by the Energy Agency of Sweden, Linköping University, and more than 20 partners from academia, industry, municipalities and other several public and private organizations.

• 179.
Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305-4035, USA.
Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
Energy Stable Model Reduction of Neurons by Non-negative Discrete Empirical Interpolation2016In: SIAM Journal on Scientific Computing, ISSN 1064-8275, E-ISSN 1095-7197, Vol. 38, no 2, p. B297-B326Article in journal (Refereed)

The accurate and fast prediction of potential propagation in neuronal networks is of prime importance in neurosciences. This work develops a novel structure-preserving model reduction technique to address this problem based on Galerkin projection and nonnegative operator approximation. It is first shown that the corresponding reduced-order model is guaranteed to be energy stable, thanks to both the structure-preserving approach that constructs a distinct reduced-order basis for each cable in the network and the preservation of nonnegativity. Furthermore, a posteriori error estimates are provided, showing that the model reduction error can be bounded and controlled. Finally, the application to the model reduction of a large-scale neuronal network underlines the capability of the proposed approach to accurately predict the potential propagation in such networks while leading to important speedups.

• 180.
Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
Structural insights into protein-protein interactions governing regulation in transcription initiation and ubiquitination2015Doctoral thesis, comprehensive summary (Other academic)

Virtually every aspect of the cellular processes in eukaryotes requires that the interactions between protein molecules are well coordinated in different regulatory pathways. Any protein dysfunction involved in these regulatory pathways might lead to various pathological conditions. Understanding the structural and functional peculiarities of these proteins molecular machineries will help in formulating structure-based drug design.

The first regulatory process studied here is the RNA polymerase-II mediated transcription of the eukaryotic protein-coding genes to produce mRNAs. This process requires the formation of the ‘transcription initiation’ by the assembly of Pre-Initiation Complex (PIC) formation at a core promoter region. Regulation at this initiation level is a key mechanism for the control of gene expression that governs cellular growth and differentiation. The transcription Factor IID (TFIID) is a conserved multiprotein general transcription factor with an essential role in  nucleating the PIC formation, composed of TATA Binding Protein (TBP) and about 14 TBP Associated Factors (TAFs). The here presented crystal structure (1.97Å) of TBP bound to TAND1 and TAND2 domains from TAF1 reveals a detailed molecular pattern of interactions involving both transcriptionally activating and repressing regions in TBP, thereby uncovering central principles for anchoring of TBP-binding motifs. Together with NMR and cellular analysis, this work provides the structural basis of competitive binding with TFIIA to modulate TBP in promoter recognition.

In eukaryotes, another fundamental mechanism in the regulation of cellular physiology is the posttranslational modification of substrate proteins by ubiquitin, termed ‘ubiquitination’. Important actors in this mechanism are the ubiquitin-ligases (E3s) that culminate the transfer of ubiquitin to the substrate and govern the specificity of this system. One E3 ligase in particular, TRIM21, defines a subgroup of the Tripartite Motif (TRIM) family, which belongs to the major RING-type of E3 ubiquitin ligases, and plays an important role in pathogenesis of autoimmunity by mediating ubiquitination of transcription factors. The crystal structure (2.86Å) of the RING domain from TRIM21 in complex with UBE2E1, an E2 conjugating enzyme, together with the NMR and SAXS analysis as well as biochemical functional analysis, reveals the molecular basis for the dynamic binding interfaces. The TRIM21 mode of ubiquitin recognition and activation for catalytic transfer of ubiquitin can be modeled onto the entire TRIM family.

Finally, we explored the concepts of conformational selection in proteins as a possible key component for protein-mediated transcriptional regulation. In this framework, MexR, a bacterial repressor of the MexAB-OprM efflux pump, and its mutant Arg21Trp were studied as an example for proteins presenting different conformations. The residue Arg21Trp mutation is clinically identified to cause of Multi-Drug Resistant (MDR) by attenuated DNA binding, and leads to the overexpression of the MexAB-OprM efflux pump. With the crystal structure (2.19Å) of MexR mutant Arg21Trp, in combination with MD-simulations and SAXS for both wild-type and mutant, we could unravel the atomic details of the wild-type conformations consisting in subsets of populations of DNA bound and unbound forms. Remarkably, the mutant Arg21Trp stabilize the DNA unbound state and shifts MexR in a pre-existing equilibrium, from a repressed to a derepressed state.

Taken together, these studies substantially broaden our knowledge at a molecular level in protein interactions that are involved in transcriptional regulation and ubiquitination, studied by a carefully selected combination of complementary structural methods spanning different resolutions and time scales.

• 181.
Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:04, Karolinska Institutet, Stockholm, Sweden. Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:04, Karolinska Institutet, Stockholm, Sweden. European Molecular Biology Laboratory, Grenoble Outstation, Grenoble, France. Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering. School of Molecular Bioscience, The University of Sydney, New South Wales, Australia. Rheumatology Unit, Department of Medicine, Center for Molecular Medicine L8:04, Karolinska Institutet, Stockholm, Sweden. Department of Medical Biochemistry and Biophysics, Protein Science Facility, Karolinska Institutet, Stockholm, Sweden. Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
Structure of a TRIM21 - UBE2El complex reveals the specificity of E2 and ubiquitin recognition by TRIM E3 RINGsManuscript (preprint) (Other academic)

TRIM21, a RlNG-containing E3 ubiquitin-ligase of the TRIM  $\tiny(\underline{tri}partite \ \underline{m}otif)$ protein family, is a major autoantigen in SLE and Sjögren's syndrome as well as a modifier of interferon regulatory factors, thereby regulating innate immune signalling. We herein report the 2.86 Å crystal structure ofhuman TRIM211-91 comprising the RING domain (residues 16-55), in complex with the human E2 conjugating UBE2El enzyme (also denoted UbcH6). The crystal structure, joint with analysis by NMR and SAXS as well as structure-directed mutations and functional assays provides a detailed view of the specificity-determining contacts that support specific E2 recognition in the TRIM family. A detailed comparison of our structure with known E2 bound ubiquitin complexes, supported by biochemical analyses, reveals the molecular basis for TRIM21 interactions with donor ubiquitin that activates catalytic ubiquitin transfer. Finally, our structure convincingly demonstrates the placement of the Ub-targeted Lys61 of the adjacent TRIM21$\small^,$1- 91 close to the catalytically active UBE2El cysteine, and how the Lys61 amide is activated fora nucleophilic attack by hydrogen-bondeffected deshielding by conserved acidic residues at the E2 active site. In all, our structural findings provide molecular details ofthe selectivity involved in TRIM21 interactions with its cognate UBE2E1 enzyme and how TRIM21 positions ubiquitin in a catalytic conformation for ubiquitin transfer, and presents a snapshot of the Ub ligation step on a specific target residue of TRIM211-91 as an auto-ubiquitinated pseudo-substrate at high concentration. Increased structural and functional understanding of the TRIM mediated ubiquitination will aid development ofnovel therapeutic approaches in the entire TRIM family ofproteins.

• 182.
Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering. University of Sydney, Australia. Karolinska Institute, Sweden. Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
Mutation-Induced Population Shift in the MexR Conformational Ensemble Disengages DNA Binding: A Novel Mechanism for MarR Family Derepression2016In: Structure, ISSN 0969-2126, E-ISSN 1878-4186, Vol. 24, no 8, p. 1311-1321Article in journal (Refereed)

MexR is a repressor of the MexAB-OprM multidrug efflux pump operon of Pseudomonas aeruginosa, where DNA-binding impairing mutations lead to multidrug resistance (MDR). Surprisingly, the crystal structure of an MDR-conferring MexR mutant R21W (2.19 angstrom) presented here is closely similar to wildtype MexR. However, our extended analysis, by molecular dynamics and small-angle X-ray scattering, reveals that the mutation stabilizes a ground state that is deficient of DNA binding and is shared by both mutant and wild-type MexR, whereas the DNA-binding state is only transiently reached by the more flexible wild-type MexR. This population shift in the conformational ensemble is effected by mutation-induced allosteric coupling of contact networks that are independent in the wild-type protein. We propose that the MexR-R21W mutant mimics derepression by small-molecule binding to MarR proteins, and that the described allosteric model based on population shifts may also apply to other MarR family members.

• 183.
Drexel University, PA 19104 USA; Drexel University, PA 19104 USA.
Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Drexel University, PA 19104 USA. Drexel University, PA 19104 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Drexel University, PA 19104 USA. Drexel University, PA 19104 USA; Nucl Research Centre Negev, Israel. Drexel University, PA 19104 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Drexel University, PA 19104 USA.
Experimental and theoretical characterization of ordered MAX phases Mo2TiAlC2 and Mo2Ti2AlC32015In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 118, no 9, p. 094304-Article in journal (Refereed)

Herein, we report on the phase stabilities and crystal structures of two newly discovered ordered, quaternary MAX phases-Mo2TiAlC2 and Mo2Ti2AlC3-synthesized by mixing and heating different elemental powder mixtures of mMo:(3-m) Ti:1.1Al:2C with 1.5 less than= m less than= 2.2 and 2Mo: 2Ti:1.1Al:2.7C to 1600 degrees C for 4 h under Ar flow. In general, for m greater than= 2 an ordered 312 phase, (Mo2Ti) AlC2, was the majority phase; for mless than 2, an ordered 413 phase (Mo2Ti2)AlC3, was the major product. The actual chemistries determined from X-ray photoelectron spectroscopy (XPS) are Mo2TiAlC1.7 and Mo2Ti1.9Al0.9C2.5, respectively. High resolution scanning transmission microscopy, XPS and Rietveld analysis of powder X-ray diffraction confirmed the general ordered stacking sequence to be Mo-Ti-Mo-Al-Mo-Ti-Mo for Mo2TiAlC2 and Mo-Ti-Ti-Mo-Al-Mo-Ti-Ti-Mo for Mo2Ti2AlC3, with the carbon atoms occupying the octahedral sites between the transition metal layers. Consistent with the experimental results, the theoretical calculations clearly show that M layer ordering is mostly driven by the high penalty paid in energy by having the Mo atoms surrounded by C in a face-centered configuration, i.e., in the center of the Mn+1Xn blocks. At 331 GPa and 367 GPa, respectively, the Youngs moduli of the ordered Mo2TiAlC2 and Mo2Ti2AlC3 are predicted to be higher than those calculated for their ternary end members. Like most other MAX phases, because of the high density of states at the Fermi level, the resistivity measurement over 300 to 10K for both phases showed metallic behavior. (C) 2015 AIP Publishing LLC.

• 184.
Drexel University, PA 19104 USA; Drexel University, PA 19104 USA.
Oak Ridge National Lab, TN 37831 USA. Drexel University, PA 19104 USA; Drexel University, PA 19104 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Drexel University, PA 19104 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Oak Ridge National Lab, TN 37831 USA; Oak Ridge National Lab, TN 37831 USA. Drexel University, PA 19104 USA; Drexel University, PA 19104 USA. Drexel University, PA 19104 USA.
Two-Dimensional, Ordered, Double Transition Metals Carbides (MXenes)2015In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 9, no 10, p. 9507-9516Article in journal (Refereed)

The higher the chemical diversity and structural complexity of two-dimensional (2D) materials, the higher the likelihood they possess unique and useful properties. Herein, density functional theory (DFT) is used to predict the existence of two new families of 2D ordered, carbides (MXenes), MM-2 C-2 and MM-2 C-2(3), where M and M are two different early transition metals. In these solids, M layers sandwich M" carbide layers. By synthesizing Mo2TiC2Tx, Mo2Ti2C3Tx, and Cr2TiC2Tx (where T is a surface termination), we validated the DFT predictions. Since the Mo and Cr atoms are on the outside, they control the 2D flakes chemical and electrochemical properties. The latter was proven by showing quite different electrochemical behavior of Mo2TiC2Tx and Ti3C2Tx. This work further expands the family of 2D materials, offering additional choices of structures, chemistries, and ultimately useful properties.

• 185.
European Spallat Source, Sweden.
European Spallat Source, Sweden. Spallat Neutron Source, TN 37831 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. European Spallat Source, Sweden. Institute Laue Langevin, France. Institute Laue Langevin, France. European Spallat Source, Sweden. Spallat Neutron Source, TN 37831 USA. Institute Laue Langevin, France. Spallat Neutron Source, TN 37831 USA. Institute Laue Langevin, France. European Spallat Source, Sweden; Mid Sweden University, Sweden. Spallat Neutron Source, TN 37831 USA. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. European Spallat Source, Sweden. European Spallat Source, Sweden. European Spallat Source, Sweden. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. European Spallat Source, Sweden. European Spallat Source, Sweden; University of Newcastle, Australia. European Spallat Source, Sweden. European Spallat Source, Sweden. European Spallat Source, Sweden. Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, Faculty of Science & Engineering. European Spallat Source, Sweden. European Spallat Source, Sweden.
Multi-Grid detector for neutron spectroscopy: results obtained on time-of-flight spectrometer CNCS2017In: Journal of Instrumentation, ISSN 1748-0221, E-ISSN 1748-0221, Vol. 12, article id P04030Article in journal (Refereed)

The Multi-Grid detector technology has evolved from the proof-of-principle and characterisation stages. Here we report on the performance of the Multi-Grid detector, the MG. CNCS prototype, which has been installed and tested at the Cold Neutron Chopper Spectrometer, CNCS at SNS. This has allowed a side-by-side comparison to the performance of He-3 detectors on an operational instrument. The demonstrator has an active area of 0.2m(2). It is specifically tailored to the specifications of CNCS. The detector was installed in June 2016 and has operated since then, collecting neutron scattering data in parallel to the He-3 detectors of CNCS. In this paper, we present a comprehensive analysis of this data, in particular on instrument energy resolution, rate capability, background and relative efficiency. Stability, gamma-ray and fast neutron sensitivity have also been investigated. The effect of scattering in the detector components has been measured and provides input to comparison for Monte Carlo simulations. All data is presented in comparison to that measured by the He-3 detectors simultaneously, showing that all features recorded by one detector are also recorded by the other. The energy resolution matches closely. We find that the Multi-Grid is able to match the data collected by He-3, and see an indication of a considerable advantage in the count rate capability. Based on these results, we are confident that the Multi-Grid detector will be capable of producing high quality scientific data on chopper spectrometers utilising the unprecedented neutron flux of the ESS.

• 186.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Assessing the Contribution of Organic Agriculture: PovertyReduction and Employment Creation in Selected Value Chains2016In: Vulnerability of Agricultural Production Networks and Global Food Value Chainsdue to Natural Disasters: Book of Abstracts / [ed] Meinhard Breiling, Anbumozhi Venkatachalam, Vienna: TU Wien , 2016, p. 23-24Conference paper (Refereed)

Organic agriculture (OA) is increasingly viewed as an economic opportunity for farmers allover the world. This paper addresses the effects of OA in terms of income, vulnerability andpoverty alleviation in rural areas in developing countries. It is based on a literature reviewwith emphasis on two value chains: cotton and coffee, which both involve smallholders indeveloping regions, and growing organic markets, but differ in terms of value chain structuresand geographical patterns.

• 187.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Hamnarna rustas för fartygens avloppsvatten2014In: Sjöfarten kring Sverige och dess påverkan på havsmiljön / [ed] Tina Johansen Lilja och Eva-Lotta Sundblad, Göteborg: Havsmiljöinstitutet , 2014, no 4, p. 10-11Chapter in book (Other academic)

När avloppsvatten från sjöfarten släpps ut i havet påverkar det miljön negativt genom att bakterier sprids och näringsämnen kommer ut i havet. Utsläppen är koncentrerade till farleder och hamnar och där kan effekterna vara tydliga, även om utsläppen är små i förhållande till de totala utsläppen till havet.

• 188.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Urban green growth-myth or reality?2015In: URBACT II New Urban Economies : How can cities foster economic development and develop ‘new urban economies’ / [ed] Willem van Winden, Luis Carvalho, Saint-Denis, France: URBACT II Programme , 2015, p. 35-38Chapter in book (Other academic)

‘To create the most resource-efficient region in the world’. This is the vision of Tekniska verken, the municipalityowned infrastructural company in Linköping, Sweden. It reflects the city’ s long-standing ambitions to be a ‘forerunner in climate and environmental initiatives’ and to support ‘business-driven’ environmental development, actively stimulating the development of a green economic sector. Linköping and the surrounding county of Östergötland are here used for discussing the development of the green economy in cities and regions.

• 189.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Western harbor in Malmö2015In: Review 11. Re-inventing planning: examples from the Profession, Rotterdam, Nederländerna: International Society of City and Regional Planners , 2015, Vol. 11, p. 210-227Conference paper (Other academic)

For the last 15 years Västra hamnen (Western Harbor) in Malmö, and Hammarby Sjöstad in Stockholm have been the major flagships of Swedish international eco-city ambitions. These city development projects are presented both as leading examples of the conversion of former industrial harbor areas and of environmental adaptation of densely built urban environments. Western Harbor is a centrally located former shipyard area which, since the end of the 1990s, has developed into a mixed city area for housing, schools, offices, shops and other workplaces as well as for recreational areas with beaches, parks and yacht harbors. Since its first phase, part of a housing expo in 2001, it has attracted international interest for its dense architecture, bold energy goals based on varied local renewable energy production, household waste systems, green and blue structures, and dialogue processes. By 2031, when the area is completed, it is expected to be the home for 25,000 people and 25,000 workplaces. In 2014, there were 7,300 inhabitants and more than 12,000 work places in Western Harbor, already twice of the work force of the former shipyard at its height.

• 190.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Företagsekonomiska institutionen, Handelshögskolan, Göteborgs universitet. Företagsekonomiska institutionen, Handelshögskolan, Göteborgs universitet.
Utsläppshandel kan vara en lönsam vägtill lägre utsläpp från sjöfarten2017In: Åtgärder för att minska sjöfartens påverkan på havsmiljön / [ed] Tina Johansen Lilja, Frida Lundberg och Eva-Lotta Sundblad., Göteborg: Havsmiljöinstitutet , 2017, p. 14-16Chapter in book (Other academic)

Handel med utsläppsrätter under ett fastställt ”tak” av totalautsläpp som efterhand sänks, har i en del regioner i världenvisat sig vara en både kostnadseffektiv och framgångsrikstrategi för att minska luftföroreningarna. Frågan är om utsläppshandelskulle kunna vara ett effektivt sätt för att minskasjöfartens utsläpp i Europa eller Östersjöregionen?

• 191.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Sjöfart och marin teknik/maritim miljö och energisystem, Chalmers tekniska högskola, Göteborg.
Billigare avfallshantering i hamnarna har inte gett förväntad effekt2017In: Åtgärder för att minska sjöfartens påverkan på havsmiljön / [ed] Tina Johansen Lilja, Frida Lundberg och Eva-Lotta Sundblad, Göteborg: Havsmiljöinstitutet , 2017, p. 26-27Chapter in book (Other academic)

Hamnarna kan spela en viktig roll för att minska sjöfartensutsläpp i havet. Reglerna för fartygens avfallsdumpning harskärpts och i Östersjöområdet har det länge funnits en överenskommelseom att fartygen ska kunna lämna sitt avfall ihamn utan extra avgift. I praktiken låter dock de stora förbättringarnavänta på sig.

• 192.
Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, Faculty of Science & Engineering.
Sjöfart och marin teknik/maritim miljö och energisystem, Chalmers tekniska högskola, Göteborg.
Expanderande kryssningsbransch ställer krav på Östersjöns hamnar2017In: Åtgärder för att minska sjöfartens påverkan på havsmiljön / [ed] Tina Johansen Lilja, Frida Lundberg och Eva-Lotta Sundblad, Göteborg: Havsmiljöinstitutet , 2017, p. 24-25Chapter in book (Other (popular science, discussion, etc.))

Kryssningssjöfarten ger växande inkomster för kuststäderna,men innebär också ökad påverkan på miljön i Östersjön och dess hamnar. Trots att branschen åtagit sig att sluta släppa utavloppsvatten till sjöss lämnar bara var tredje kryssningsfartygsitt avfallsvatten vid hamnbesök. Dessutom är delar av fartygsflottani stort behov av förbättrad miljöprestanda.

• 193.
Linköping University, Department of Computer and Information Science. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transport Research Institute (VTI), Linköping, Sweden.
Extensions for Distributed Moving Base Driving Simulators2017Licentiate thesis, comprehensive summary (Other academic)

Modern vehicles are complex systems. Different design stages for such a complex system include evaluation using models and submodels, hardware-in-the-loop systems and complete vehicles. Once a vehicle is delivered to the market evaluation continues by the public. One kind of tool that can be used during many stages of a vehicle lifecycle is driving simulators.

The use of driving simulators with a human driver is commonly focused on driver behavior. In a high fidelity moving base driving simulator it is possible to provide realistic and repetitive driving situations using distinctive features such as: physical modelling of driven vehicle, a moving base, a physical cabin interface and an audio and visual representation of the driving environment. A desired but difficult goal to achieve using a moving base driving simulator is to have behavioral validity. In other words, \A driver in a moving base driving simulator should have the same driving behavior as he or she would have during the same driving task in a real vehicle.".

In this thesis the focus is on high fidelity moving base driving simulators. The main target is to improve the behavior validity or to maintain behavior validity while adding complexity to the simulator. One main assumption in this thesis is that systems closer to the final product provide better accuracy and are perceived better if properly integrated. Thus, the approach in this thesis is to try to ease incorporation of such systems using combinations of the methods hardware-in-the-loop and distributed simulation. Hardware-in-the-loop is a method where hardware is interfaced into a software controlled environment/simulation. Distributed simulation is a method where parts of a simulation at physically different locations are connected together. For some simulator laboratories distributed simulation is the only feasible option since some hardware cannot be moved in an easy way.

Results presented in this thesis show that a complete vehicle or hardware-in-the-loop test laboratory can successfully be connected to a moving base driving simulator. Further, it is demonstrated that using a framework for distributed simulation eases communication and integration due to standardized interfaces. One identified potential problem is complexity in interface wrappers when integrating hardware-in-the-loop in a distributed simulation framework. From this aspect, it is important to consider the model design and the intersections between software and hardware models. Another important issue discussed is the increased delay in overhead time when using a framework for distributed simulation.

• 194.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering. Swedish National Road and Transportation Research Institute.
Linköping University, Department of Computer and Information Science, Software and Systems. Linköping University, Faculty of Science & Engineering.
Models for Distributed Real-Time Simulation in a Vehicle Co-Simulator Setup2013In: Proceedings of the 5th International Workshop on Equation-Based Object-Oriented Modeling Languages and Tools; April 19, University of Nottingham, Nottingham, UK / [ed] Henrik Nilsson, Linköping: Linköping University Electronic Press, 2013, Vol. 84, p. 131-139Conference paper (Refereed)

A car model in Modelica has been developed to be used in a new setup for distributed real-time simulation where a moving base car simulator is connected with a real car in a chassis dynamometer via a 500m fiber optic communication link. The new co-simulator set-up can be used in a number of configurations where hardware in the loop can be interchanged with software in the loop. The models presented in this paper are the basic blocks chosen for modeling the system in the context of a distributed real-time simulation; estimating parameters for the powertrain model; the choice of numeric solver; and the interaction with the solver for real-time properties.

Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
Att uppleva räta linjer och grafer – erfarenheter från ett forskningsprojekt2015In: Nämnaren 2014:4, no 1, p. 21-27Article in journal (Other (popular science, discussion, etc.))
• 196.
Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
Design of the Modelica Library VehProLib with Non-ideal Gas Models in Engines2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

This thesis covers the reconstruction and the redesign of the modeling library VehProLib,which is constructed in the modeling language Modelica with help of the modeling toolWolfram SystemModeler. The design choices are discussed and implemented. This thesisalso includes the implementation of a turbocharger package and an initial study of the justificationof the ideal gas law in vehicle modeling. The study is made with help of Van derWaals equation of states as a reference of non-ideal gas model. It will be shown that for themean-value-engine-model, the usage of ideal gas law is justified.

• 197.
Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
A study of the comparability of energy audit program evaluations2017In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 142, p. 2133-2139Article in journal (Refereed)

There is a large untapped potential for improved energy efficiency in various sectors of the economy. Governmental industrial energy audit programs subsidizing the companies to conduct an energy audit are the most common policy in trying to overcome the energy efficiency gap. Evaluation studies have been carried out to gain knowledge about the success of a completed energy audit policy program. The evaluations were made in different ways and in addition focused on different performance indicators and used different ways of categorizing data. In this article, a literature review has been made of five evaluation studies from different energy audit programs, where the problems of the present incomparability between programs due to differences are discussed. The policy implication of this paper is that new energy audit policy programs must distinguish a harmonized way of categorizing data, both regarding energy efficiency measures and energy end-use. Further, a proposition for a standard for how to evaluate energy audit policy programs is suggested. Conclusions from this study are that important elements, such as the free-rider effect and harmonized energy end-use data, should be defined and included in evaluation studies. A harmonized standard for evaluating audit programs is not least needed within the EU, where member states are obliged to launch audit programs for large enterprises, and preferably also for small and medium-sized enterprises. This paper serves as an important contribution for the development of such a standard in further research. (C) 2016 Elsevier Ltd. All rights reserved.

The full text will be freely available from 2018-11-12 17:53
• 198.
Linköping University, Department of Electrical Engineering, Vehicular Systems. Linköping University, Faculty of Science & Engineering.
Modelling of Cranking Behaviour in Heavy Duty Truck Engines2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

In modern heavy duty trucks the battery is a central component. Its traditional role as an energy source for engine cranking has been extended to include powering a number of elec- trical components on the truck, both during driving and during standstill. As a consequence of this it is important to know how much a battery in use has aged and lost in terms of ca- pacity and power output. The difficulty in measuring these factors on a battery in use causes problem, since heavy duty truck batteries are often replaced too early or too late, leading to unnecessary high replacement costs or truck standstill respectively.

The overall goal of the effort, of which this thesis is a part, is to use a model of the cranking behaviour of a heavy duty truck engine, which depends on the battery condition, to estimate the ageing and wear of a heavy duty truck battery. This thesis proposes a modelling approach to model the components involved in engine cranking.

In the thesis work, system identification is made of the systems forming part of the cranking of a heavy duty truck engine. These components are the starter battery, the starter motor and its electrical circuit and the internal combustion engine. Measurement data has been provided by Scania AB for the evaluation of the models. The data has been collected from crankings of a heavy duty diesel engine at different temperatures and battery charge levels. For every cranking lapse the battery voltage and current have been measured as well as the engine rotational speed.

A starter battery model is developed and evaluated. The resulting battery model is then incorporated into two different engine cranking models, Model 1 and Model 2, including a starter motor model and an internal combustion engine model apart form the battery model. The two cranking models differ in several aspects and their differences and resulting evalu- ations are discussed.

The battery model is concluded to be sufficiently accurate during model verification, however the two cranking models are not. Model 2 is verified as more correct in in its output than Model 1, but neither is sufficiently accurate for their purpose. The conclusion is drawn that the modelling approach is sound but development of Model 2 is needed before the model can be used in model-based condition estimation.

• 199.
Linköping University, Department of Computer and Information Science, Database and information techniques. Linköping University, Faculty of Science & Engineering.
Storing and structuring big data with businessintelligence in mind2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis

Sectra has a customer database with approximately 1600 customers across the world. In this system there exists not only medical information but alsoinformation about the environment which the system runs in, usage  pattern and much more.

This report is about storing data received from log les into a suitable database. Sectra wants to be able to analyze this information so that they can make strategic decisions and get a better understanding of their customers' needs. The tested databases are MongoDB, Cassandra, and MySQL. The results shows that MySQL  is not suitable for storing large amount of data with the current conguration. On the other hand, both MongoDB and Cassandra performed well with the growing amount of data.

• 200.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
Configuration and Planning of the Remote TowerModules in a Remote Tower Center2016Conference paper (Refereed)

Today, many small aerodromes struggle withfinancial difficulties, and a large cost is air traffic control.Remote tower centers, which remotely provide air traffic servicesto aerodromes, can help reduce this cost. Each center maycontain a number of remote tower modules, where each moduleis manned by a controller that can handle one or moreaerodromes. In this paper we present the remote tower centerconcept and develop a model that optimizes the assignment ofairports to the remote tower modules. Computational results fora possible scenario based on real data for Swedish airports arepresented.

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