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Towards knowledge-based geovisualisation using Semantic Web technologies:a knowledge representation approach coupling ontologies and rules

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International Journal of Digital Earth 2020年第9期13卷 976-997页

作者： Weiming Huang lars Harrie Department of Physical Geography and Ecosystem Science Lund UniversityLundSweden

Geovisualisation is a knowledge-intensive art in which both providers and users need to possess a wide range of *** syntactic approaches to presenting visualisation information lack semantics on the one hand,and on the other hand are too *** limitations impede the transfer,interpretation,and reuse of the geovisualisation *** this paper,we propose a knowledge-based approach to formally represent geovisualisation knowledge in a semantically-enriched and machine-readable manner using Semantic Web ***,we represent knowledge regarding cartographic scale,data portrayal and geometry source,which are three key aspects of geovisualisation in the contemporary web mapping era,coupling ontologies and semantic *** knowledge base enables inference for deriving the corresponding geometries and portrayals for visualisation under different conditions.A prototype system is developed in which geospatial linked data are used as underlying data,and some geovisualisation knowledge is formalised into a knowledge base to visualise the data and provide rich semantics to *** proposed approach can partially form the foundation for the vision of web of knowledge for geovisualisation.

关键词： Geovisuaisation Semantic Web knowledge representation ontologies semantic rules

A Structural Bisulfite Assay to Identify DN Cruciforms

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Molecular Plant 2016年第9期9卷 1328-1336页

作者： Matthew Gentry lars Hennig Department of Plant Biology Uppsala BioCenter Swedish University of Agricultural Sciences and Linnean Center for Plant Biology 75007 Uppsala Sweden

In the half century since the discovery of the double-helix structure of DNA, it has become increasingly clear that DNA functionality is based on much more than its sequence in a double-helical structure. Further advances have highlighted the importance of additional aspects of DNA structure： its packaging in the higher order chromatin structure, positioning of nucleosomes along the DNA, and the occurrence of non-helical DNA structures. of these, the latter has been problematic to prove empirically. Here, we describe a method that uses non-denaturing bisulfite sequencing on isolated Arabidopsis thaliana nuclei to determine the location of cytosines positioned outside the double helix as a result of non-B-form DNA structures. We couple this with computational methods and S1 nuclease digest to reliably identify stable, non-B-form, cruciform structures. This enables us to identify a palindrome in the promoter of FLoWERING LoCUS T that forms a stable non-B-form structure. The stronger conservation of the ability to form a nonhelical secondary structure than of the sequence suggests that this structure is biologically relevant.

关键词： DNA structure cruciform DNA genome organization

Short-chain fatty acids in the context of Parkinson’s disease

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Neural Regeneration Research 2021年第10期16卷 2015-2016页

作者： Judith Metzdorf lars Tonges Department of Neurology St.Josef-HospitalRuhr-University BochumBochumGermany

Research on neurodegenerative diseases such as Alzheimer’s disease,Parkinson´s disease(PD),Huntington’s disease or amyotrophic lateral sclerosis is becoming increasingly important in our *** to the ageing of the population,the prevalence of these diseases continue to rise worldwide,and causal cures are not yet available(Erkkinen et al.,2018).This Perspective focusses on PD,a movement disorder of the central nervous system with an estimated prevalence between 65 and 1250/100,000 in Europe,affecting about 1 percent of the population older than 60 *** clinical symptoms include motor symptoms like bradykinesia,tremor or rigidity which are associated with loss of dopaminergic neurons in the substantia nigra and their innervating axonal fibers to the *** non-motor symptoms may consist in depression,hyposmia,cognitive decline or constipation due to impaired motility of the gastrointestinal tract.

关键词： Huntington impaired diseases

Real-time visualization of 3D city models at street-level based on visual saliency

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Science China Earth Sciences 2015年第3期58卷 448-461页

作者： MAo Bo BAN YiFang lars HARRIE Jiangsu Provincial Key Laboratory of E-Business Nanjing University of Finance and Economics College of Computer Science and Engineering Nanjing University of Science and Technology Department of Urban Planning and Environment KTH Royal Institute of TechnologySE-10044 StockholmSweden Department of Physical Geography and Ecosystem Science Lund UniversityBox118SE-223 62 LundSweden

Street-level visualization is an important application of 3D city *** to street-level visualization include the cluttering of buildings due to fine detail and visualization *** this paper,a novel method is proposed for streetlevel visualization based on visual saliency *** basic idea of the method is to preserve these salient buildings in a scene while removing those that are *** method can be divided into pre-processing procedures and real-time *** first step in pre-processing is to convert 3D building models at higher Levels of Detail(Lo Ds) into LoD 1 models with simplified ground ***,a number of index viewpoints are created along the streets; these indices refer to both the position and the direction of each street site.A visual saliency value is computed for each building,with respect to the index site,based on a visual difference between the original model and the generalized *** calculate and evaluate three methods for visual saliency:local difference,global difference and minimum projection *** real-time visualization process begins by mapping the observer to its closest *** street view is then generated based on the building information stored in those indexes.A user study shows that the local visual saliency method performs better than do the global visual saliency,area and image-based methods and that the framework proposed in this paper may improve the performance of 3D visualization.

关键词： 3D city models street level visualization index viewpoints visual saliency

High throughput screening of localised and general corrosion in type 2205 duplex stainless steel at ambient temperature

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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2375-2385页

作者： Yiqi Zhou Sultan Mahmood Dirk lars Engelberg Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Metallurgy and Corrosion School of MaterialsThe University of ManchesterM139PLManchesterUK Materials Performance Centre The University of ManchesterM139PLManchesterUK

Bipolar electrochemistry is used to produce a linear potential gradient across a bipolar electrode(BPE),providing direct access to the anodic and cathodic reactions under a wide range of applied *** occurrence of pitting corrosion,crevice corrosion,and general corrosion on type 2205 duplex stainless steel(DSS 2205)BPE has been observed at room *** critical pit depth of 10-20μm with a55%-75% probability of pits developing into stable pits at potential from+0.9 to+1.2 V ***(open circuit potential)are *** pit nucleation sites are either within ferritic grains or at the interface between austenite and *** critical conditions for pitting and crevice corrosion are discussed with Epit(critical pitting potential)and Ecre(critical crevice potential)decreasing from 0.87 and 0.80 V *** after150 s of exposure to 0.84 and 0.76 V *** after 900 s of exposure,*** growth kinetics under different applied bipolar potentials and exposure times have been *** ferrite is shown to be more susceptible to general dissolution.

关键词： bipolar electrochemistry duplex stainless steel pitting corrosion pit growth factor crevice corrosion

Integrated photonics in the 21st century

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Photonics Research 2014年第2期2卷 75-81页

作者： lars Thylén Lech Wosinski Laboratory of Photonics and Microwave Engineering Royal Institute of Technology(KTH)SE-16440 KistaSweden Hewlett-Packard Laboratories Palo AltoCalifornia 94304USA Joint Research Center of Photonics of the Royal Institute of Technology(KTH)and Zhejiang University Zhejiang UniversityHangzhou 310058China

We review the emergence and development of integrated photonics and its status *** treatise is focused on information and communications technology(ICT)applications,but the technology is generically employable for a wealth of other applications,such as *** properties of the waveguides that form the basis of integrated photonics are reviewed,and several examples of integrated photonics based on silicon and plasmonics are *** all-important development of integrated low-power nanophotonics is discussed and current challenges and prospects of the field are *** treatment is focused on the photonic fabric between source and detector.

关键词： photonics waveguides treatment

Improving Fault Detection in Modified Code-A Study from the Telecommunication Industry

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Journal of Computer Science & Technology 2007年第3期22卷 397-409页

作者： Piotr Tomaszewski lars Lundberg Hkan Grahn School of Engineering Blekinge Institute of Technology SE-372 25 RonnebySweden

Many software systems are developed in a number of consecutive releases. In each release not only new code is added but also existing code is often modified. In this study we show that the modified code can be an important source of faults. Faults are widely recognized as one of the major cost drivers in software projects. Therefore, we look for methods that improve the fault detection in the modified code. We propose and evaluate a number of prediction models that increase the efficiency of fault detection. To build and evaluate our models we use data collected from two large telecommunication systems produced by Ericsson. We evaluate the performance of our models by applying them both to a different release of the system than the one they are built on and to a different system. The performance of our models is compared to the performance of the theoretical best model, a simple model based on size, as well as to analyzing the code in a random order （not using any model）. We find that the use of our models provides a significant improvement over not using any model at all and over using a simple model based on the class size. The gain offered by our models corresponds to 38-57% of the theoretical maximum gain.

关键词： fault prediction metrics testing and debugging

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

Towards Accurate Bit Error Simulation in Wireless Sensor Networks Including Environmental Influences

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Journal of Computer Science & Technology 2020年第4期35卷 809-824页

作者： Sven Pullwitt Robert Hartung Ulf Kulau lars Wolf Institute for operating Systems and Computer Networks Technische Universitat BraunschweigBraunschweig 38106 Germany

Simulation is a common technique for the evaluation of new approaches and protocols in networked systems and provides many ***,it is also well known that the relevance of the simulation results for real-world applications depends on the various models which are used within the simulation,e.g.,for the characteristics of the radio *** this paper,we introduce the Extended Multipath Raytracing Model,an extension to the ray-tracing radio medium available in Cooja,to improve the modelling of wireless links in simulated Wireless Sensor *** extension allows the simulation of environmental influences onto links on a per node basis,allowing the analysis of various effects observed in experiments in a virtual ***,the packet-based modelling of transmission errors is extended to provide the simulation of bit errors,allowing new usage scenarios,like the simulation of error detection and Forward Error Correction codes in Cooja.

关键词： bit error Contiki Cooja environmental influence simulation wireless sensor network