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An overview of various control benchmarks with a focus on automotive control

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Control Theory and Technology 2019年第2期17卷 121-130页

作者： Lars eriksson Vehicular Systems Department of Electrical EngineeringLinkoping UniversitySE-581 83 LinkopingSweden

There exists a gap between control theory and control practice,i.e.,all control methods suggested by researchers are not implemented in real systems and,on the other hand,many important in dustrial problems are not studied in the academic *** problems can help close this gap and provide many opportunities for members in both the controls theory and application *** goal is to survey and give pointers to different general controls and modeling related benchmark problems that can serve as inspiration for future benchmarks and then specifically focus the benchmark coverage on automotive control engineering *** the paper reflections are given on how different categories of benchmark designers,benchmark solvers and third part users can benefit from providing,solving,and studying benchmark *** paper also collects information about several benchmark problems and gives pointers to papers than give more detailed information about different problems that have been presented.

关键词： Benchmark automotive control robust control robotics engine control powertrain control system identification

Irritable bowel syndrome subtypes differ in body awareness, psychological symptoms and biochemical stress markers

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World Journal of Gastroenterology 2008年第31期14卷 4889-4896页

作者： Elsa M eriksson kristina I Andrén Henry T eriksson Gran K Kurlberg Department of Medicine Sahlgrenska University Hospital/stra Gteborg SE-41685 Sweden Department of Surgery Sahlgrenska University Hospital/stra Gteborg SE-41685 Sweden Department of Medicine Sahlgrenska University Hospital/stra Gteborg SE-41685 Sweden Department of Surgery Sahlgrenska University Hospital/stra Gteborg SE-41685 Sweden

AIM: To elucidate the differences in somatic, psycho-logical and biochemical pattern between the subtypes of irritable bowel syndrome (IBS). METHODS: Eighty IBS patients, 30 diarrhoea pre-dominant (D-IBS), 16 constipation predominant (C-IBS) and 34 alternating IBS (A-IBS) underwent physi-otherapeutic examinations for dysfunctions in body movements and awareness and were compared to an apparently healthy control group (AHC). All groups an-swered questionnaires for gastrointestinal and psycho-logical symptoms. Biochemical variables were analysed in blood. RESULTS: The D-IBS group showed less body aware-ness, less psychological symptoms, a more normal sense of coherence and psychosocial rating as well as higher C-peptide values. C-IBS had a higher degree of body dysfunction and psychological symptoms, as well as the lowest sense of coherence compared to controls and D-IBS. They also demonstrated the most elevated prolactin levels. A-IBS had the lowest degree of body disturbance, deteriorated quality of life and affected bi-ochemical pattern. All subtypes had higher pain scores compared to controls. In addition they all had signifi -cantly increased triglycerides and elevated morning cortisol levels, however, without statistical signifi cance compared with the ***: IBS subtypes showed different pro-files in body awareness, somatic and psychological symptoms and in biochemical variables. D-IBS differed compared to the other groups by lowered body aware-ness, less psychological symptoms and a higher sense of coherence and elevated C-peptide values. C-IBS and A-IBS subtypes suffered more from depression and anxiety, associated with a lower quality of life. These differences may be important and will be taken into account in our treatment of these patients.

关键词： Irritable bowel syndrome subtypes Physiotherapy Body awareness Stress Biochemistry

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冰岛东部最美小镇白日梦想家们的隐世仙境

环球人文地理 2024年第13期 144-153页

作者：邓文倩 Vladimir marieagns Nataliya Fotokon Sen Isabel Baldovi Marc Jedamus kristina Ryan Unsplash 摄图网

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉...

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉雅山脉……但实际上整部电影的取景地全都在冰岛。影片最令人印象深刻的部分，大概是沃尔特用公仔和小孩子交换滑板后，在一条盘山公路上急速滑行。公路的尽头就是被LonelyPlanet评为“冰岛东部最美小镇”的塞济斯菲厄泽。

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Real-time performance of DAE and ODE based estimators evaluated on a diesel engine

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Science China(Information Sciences) 2018年第7期61卷 27-39页

作者： Erik H?CKERDAL Erik FRISK Lars eriksson Scania CV AB Vehicular Systems Link?ping University

Computation and sampling time requirements for real-time implementation of observers is studied. A common procedure for state estimation and observer design is to have a system model in continuous time that is converted to sampled time with Euler forward method and then the observer is designed and implemented in sampled time in the real time system. When considering state estimation in real time control systems for production there are often limited computational resources. This becomes especially apparent when designing observers for stiff systems since the discretized implementation requires small step lengths to ensure stability. One way to reduce the computational burden, is to reduce the model stiffness by approximating the fast dynamics with instantaneous relations, transforming an ordinary differential equations(ODE)model into a differential algebraic equation(DAE) model. Performance and sampling frequency limitations for extended Kalman filter(EKF)'s based on both the original ODE model and the reduced DAE model are here analyzed and compared for an industrial system. Furthermore, the effect of using backward Euler instead of forward Euler when discretizing the continuous time model is also analyzed. The ideas are evaluated using measurement data from a diesel engine. The engine is equipped with throttle, exhaust gas recirculation(EGR), and variable geometry turbines(VGT) and the stiff model dynamics arise as a consequence of the throttle between two control volumes in the air intake system. The process of simplifying and modifying the stiff ODE model to a DAE model is also discussed. The analysis of the computational effort shows that even though the ODE, for each time-update, is less computationally demanding than the resulting DAE, an EKF based on the DAE model achieves better estimation performance than one based on the ODE with less computational effort. The main gain with the DAE based EKF is that it allows increased step lengths without degrading the

关键词： estimation learning DAE ODE EKF observability real-time

Contribution of precursor compounds to the release of per-and polyfluoroalkyl substances(PFASs) from waste water treatment plants(WWTPs)

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Journal of Environmental Sciences 2017年第11期29卷 80-90页

作者： Ulrika eriksson Peter Haglund Anna K?rrman Man-Technology-Environment (MTM) Research Centre School of Science and Technology ?rebro University Department of Chemistry Umea University

Per-and polyfluoroalkyl substances（PFASs） are ubiquitous in sludge and water from waste water treatment plants, as a result of their incorporation in everyday products and industrial processes. In this study, we measured several classes of persistent PFASs,precursors, transformation intermediates, and newly identified PFASs in influent and effluent sewage water and sludge from three municipal waste water treatment plants in Sweden, sampled in 2015. For sludge, samples from 2012 and 2014 were analyzed as *** of precursors in sludge exceeded those of perfluoroalkyl acids and sulfonic acids（PFCAs and PFSAs）, in 2015 the sum of polyfluoroalkyl phosphoric acid esters（PAPs） were 15–20 ng/g dry weight, the sum of fluorotelomer sulfonic acids（FTSAs） was 0.8–1.3 ng/g,and the sum of perfluorooctane sulfonamides and ethanols ranged from non-detected to 3.2 ng/g. Persistent PFSAs and PFCAs were detected at 1.9–3.9 ng/g and 2.4–7.3 ng/g dry weight, respectively. The influence of precursor compounds was further demonstrated by an observed substantial increase for a majority of the persistent PFCAs and PFSAs in water after waste water treatment. Perfluorohexanoic acid（PFHxA）, perfluorooctanoic acid（PFOA）, perfluorohexane sulfonic acid（PFHxS）, and perfluorooctane sulfonic acid（PFOS）had a net mass increase in all WWTPs, with mean values of 83%, 28%, 37% and 58%,respectively. The load of precursors and intermediates in influent water and sludge combined with net mass increase support the hypothesis that degradation of precursor compounds is a significant contributor to PFAS contamination in the environment.

关键词： diPAPs FTSAs Waste water Daily discharge PFCA precursor

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Recruitment in species-rich grasslands: the effects of functional traits and propagule pressure

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Journal of Plant Ecology 2012年第3期5卷 260-269页

作者： MathiasÖster Ove eriksson Department of Botany Stockholm UniversitySE-10691 StockholmSweden

Aims The assembly of plant communities is a complex process which combines impacts from the species pool,dispersal and propagule pressure,niche requirements of colonizing species and the niche structure of the *** theory development has incorporated all these aspects,***‘stochastic niche theory’.We investigated recruitment into a species-rich grassland community,using an experimental approach where we manipulated the trait composition of the community and examined the success of colonizing species entering with various propagule ***,we examined two predictions:(i)colonization success increases with increasing difference between traits of the colonizing species and the trait profile of the community and(ii)colonization success increases with increasing propagule *** The examined communities were species-rich semi-natural grasslands located in southern *** a careful documentation of the composition of the plant communities at the experimental sites,we manipulated the trait profile of species-rich grassland plots based on the plant functional trait specific leaf area(SLA),which is correlated with several key life history *** addition to SLA,seed mass was also used to describe the trait profile of grassland *** of 12 plant species from the regional species pool,varying in SLA and seed mass,were sown into plots using four different levels of propagule *** was examined after 1 *** also planted juvenile‘plug plants’of the same species which allowed us to examine survivorship and growth beyond the seedling *** Findings Overall we found very limited evidence for relationships between the traits of the colonizing species and the trait profile of the community and for recruitment after sowing these relationships were contrary to the *** of plug plants after two seasons of growth was high irrespective of the trait profile of the community,but growth of plug

关键词： assembly rules recruitment limitation seed size semi-natural grassland SLA

Fluid Structure Interaction Problems:the Necessity of a Well Posed,Stable and Accurate Formulation

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Communications in Computational Physics 2010年第10期8卷 1111-1138页

作者： Jan Nordstrom Sofia eriksson School of Mechanical Industrial and Aeronautical EngineeringUniversity of the WitwatersrandJohannesburgWITS 2050South Africa Department of Aeronautics and Systems Integration FOIThe Swedish Defense Research AgencySE-16490 StockholmSweden Department of Information Technology Division of Scientific ComputingUppsala UniversitySE-75105 UppsalaSweden

We investigate problems of fluid structure interaction type and aim for a formulation that leads to a well posed problem and a stable numerical *** first objective is to investigate if the generally accepted formulations of the fluid structure interaction problem are the only possible *** second objective is to derive a stable numerical *** accomplish that we will use a weak coupling procedure and employ summation-by-parts operators and penalty *** compare the weak coupling with other common *** also study the effect of high order accurate *** multiple dimensions this is a formidable task and we start by investigating the simplest possible model problem *** a flow model we use the linearized Euler equations in one dimension and as the structure model we consider a spring.

关键词： Fluid structure interaction well posed finite difference high accuracy stability

Time-resolved impact electrochemistry for quantitative measurement of single-nanoparticle reaction kinetics

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Nano Research 2017年第11期10卷 3680-3689页

作者： En Ning Saw Markus Kratz kristina Tschulik Micro-&Nano-Electrochemistry and Centre for Electrochemical Sciences(CES) Ruhr-University BochumBochum D-44780Germany

Single-nanoparticle electrochemistry has been established as a tool to characterize various nanomaterials based on the charge passed during their random impact at an *** it is demonstrated that the duration and shape of the resulting current peak can be used to quantify the reaction kinetics on a single-particle *** the chemical rate constant and reaction mechanism for oxidation of single nanoparticles in different electrolytes can be determined directly from the duration of the current signal recorded in high-speed,high-sensitivity current *** 29-nm-sized Ag particles in four different electrolytes as a proof of concept for this general approach,hitherto inaccessible insights into single-particle reactivity are *** comparable rate constants were measured for the four electrolytes at low overpotentials,transport-limited impacts at high overpotentials were found to depend strongly on the type and quantity of anions present in solution.

关键词： single-particle reactivity electrochemical kinetics nano-impact method silver reaction mechanism

Efficient construction of linear models in materials modeling and applications to force constant expansions

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npj Computational Materials 2020年第1期6卷 527-537页

作者： Erik Fransson Fredrik eriksson Paul Erhart Department of Physics Chalmers University of TechnologyGothenburgSweden

Linear models,such as force constant(FC)and cluster expansions,play a key role in physics and materials *** they can in principle be parametrized using regression and feature selection approaches,the convergence behavior of these techniques,in particular with respect to thermodynamic properties is not well ***,we therefore analyze the efficacy and efficiency of several state-of-the-art regression and feature selection methods,in particular in the context of FC extraction and the prediction of different thermodynamic properties.

关键词： properties thermodynamic constant