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排序方式: 共有3161条查询结果,搜索用时 234 毫秒
71.
This article focusses on the fusion of information from various automotive sensors like radar, video, and lidar for enhanced safety and traffic efficiency. Fusion is not restricted to data from sensors onboard the same vehicle but vehicular communication systems allow to propagate and fuse information with sensor data from other vehicles or from the road infrastructure as well. This enables vehicles to perceive information from regions that are hardly accessible otherwise and represents the basis for cooperative driving maneuvers. While the Bayesian framework builds the basis for information fusion, automobile environments are characterized by their a priori unknown topology, i.e., the number, type, and structure of the perceived objects is highly variable. Multi-object detection and tracking methods are a first step to cope with this challenge. Obviously, the existence or non-existence of an object is of paramount importance for safe driving. Such decisions are highly influenced by the association step that assigns sensor measurements to object tracks. Methods that involve multiple sequences of binary assignments are compared with soft-assignment strategies. Finally, fusion based on finite set statistics that (theoretically) avoid an explicit association are discussed. 相似文献
72.
This paper introduces a system for real-time physiological measurement, analysis, and metaphorical visualization within a virtual environment (VE). Our goal is to develop a method that allows humans to unconsciously relate to parts of an environment more strongly than to others, purely induced by their own physiological responses to the virtual reality (VR) displays. In particular, we exploit heart rate, respiration, and galvanic skin response in order to control the behavior of virtual characters in the VE. Such unconscious processes may become a useful tool for storytelling or assist guiding participants through a sequence of tasks in order to make the application more interesting, e.g., in rehabilitation. We claim that anchoring of subjective bodily states to a virtual reality (VR) can enhance a person’s sense of realism of the VR and ultimately create a stronger relationship between humans and the VR. 相似文献
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74.
Sascha Kuhn August Burr Michael Kübler Matthias Deckert Christoph Bleesen 《Microsystem Technologies》2010,16(10):1787-1801
The injection molding of micro-structures is a promising mass-production method for a broad range of materials. However, the
replication quality of these structures depends significantly on the heat flow during the filling stage. In this paper, the
filling and heat transfer of v-groove and random structures below 5 μm is investigated with the help of an AFM (atomic force
microscope) and thermo couples. A numerical model is developed to predict the filling of surface structures during the filling
and packing stage. The model implies the use of simple fully developed flow models taking the power-law material model into
account. This permits investigation into which ways several processing parameters affect the polymer flow in the surface structures.
The mold wall temperature, which has significant effects on the polymer flow, is varied by using a variothermal mold temperature
control system to validate the model proposed. 相似文献
75.
Context: A number of approaches have been proposed for the general problem of software component evaluation and selection. Most approaches come from the field of Component-Based Software Development (CBSD), tackle the problem of Commercial-off-the-shelf component selection and use goal-oriented requirements modelling and multi-criteria decision making techniques. Evaluation of the suitability of components is carried out largely manually and partly relies on subjective judgement. However, in dynamic, distributed environments with high demands for transparent selection processes leading to trustworthy, auditable decisions, subjective judgements and vendor claims are not considered sufficient. Furthermore, continuous monitoring and re-evaluation of components after integration is sometimes needed.Objective: This paper describes how an evidence-based approach to component evaluation can improve repeatability and reproducibility of component selection under the following conditions: (1) Functional homogeneity of candidate components and (2) High number of components and selection problem instances.Method: Our evaluation and selection method and tool empirically evaluate candidate components in controlled experiments by applying automated measurements. By analysing the differences to system-development-oriented scenarios, the paper shows how the process of utility analysis can be tailored to fit the problem space, and describes a method geared towards automated evaluation in an empirical setting. We describe tool support and a framework for automated measurements.We further present a taxonomy of decision criteria for the described scenario and discuss the data collection means needed for each category of criteria.Results: To evaluate our approach, we discuss a series of case studies in the area of digital preservation. We analyse the criteria defined in these case studies, classify them according to the taxonomy, and discuss the quantitative coverage of automated measurements.Conclusion: The results of the analysis show that an automated measurement, evaluation and selection framework is necessary and feasible to ensure trusted and repeatable decisions. 相似文献
76.
Hummel M Garth C Hamann B Hagen H Joy KI 《IEEE transactions on visualization and computer graphics》2010,16(6):1319-1328
Integral surfaces are ideal tools to illustrate vector fields and fluid flow structures. However, these surfaces can be visually complex and exhibit difficult geometric properties, owing to strong stretching, shearing and folding of the flow from which they are derived. Many techniques for non-photorealistic rendering have been presented previously. It is, however, unclear how these techniques can be applied to integral surfaces. In this paper, we examine how transparency and texturing techniques can be used with integral surfaces to convey both shape and directional information. We present a rendering pipeline that combines these techniques aimed at faithfully and accurately representing integral surfaces while improving visualization insight. The presented pipeline is implemented directly on the GPU, providing real-time interaction for all rendering modes, and does not require expensive preprocessing of integral surfaces after computation. 相似文献
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79.
Yannis Smaragdakis Christoph Csallner Ranjith Subramanian 《Automated Software Engineering》2009,16(1):73-99
We explore the automatic generation of test data that respect constraints expressed in the Object-Role Modeling (ORM) language.
ORM is a popular conceptual modeling language, primarily targeting database applications, with significant uses in practice.
The general problem of even checking whether an ORM diagram is satisfiable is quite hard: restricted forms are easily NP-hard
and the problem is undecidable for some expressive formulations of ORM. Brute-force mapping to input for constraint and SAT
solvers does not scale: state-of-the-art solvers fail to find data to satisfy uniqueness and mandatory constraints in realistic
time even for small examples. We instead define a restricted subset of ORM that allows efficient reasoning yet contains most
constraints overwhelmingly used in practice. We show that the problem of deciding whether these constraints are consistent
(i.e., whether we can generate appropriate test data) is solvable in polynomial time, and we produce a highly efficient (interactive
speed) checker. Additionally, we analyze over 160 ORM diagrams that capture data models from industrial practice and demonstrate
that our subset of ORM is expressive enough to handle their vast majority. 相似文献
80.