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901.
The present study aimed at identifying factors for traffic safety support in older drivers. This was achieved by studying the co-operation between older drivers and their ordinary front seat passenger (co-driver). The knowledge emerging from such study can enhance the understanding of what kind of support an older driver needs and also help facilitate proper design of in-vehicle support systems and intervention training programs for older drivers. A within group field study was carried out, using a mixed-methods evaluation design. Four elderly couples participated in the study. The drivers included in the study requested and received on-going directional support, traffic -and driving strategic help, help with look-out and reminding of current speed limit. It was evident from comparisons between interview data and field data that how the participants themselves described their need of support differed from what support they requested (drivers) and gave (co-drivers) in real driving. Furthermore, data revealed that three out of four drivers were given a score of 2 in the Useful Field Of View test (UFOV). It was evident that there are areas in which older drivers need and request support. The results from the present study could be used in the design process, and in evaluation of, in-vehicle support systems as well as in developing intervention training programs customised for older drivers. 相似文献
902.
Extensive use of unmanned aerial vehicles (UAVs) in recent years has induced the rapid growth of research areas related to UAV production. Among these, the design of control systems capable of automating a wide range of UAV activities is one of the most actively explored and evolving. Currently, researchers and developers are interested in designing control systems that can be referred to as intelligent, e.g. the systems which are suited to solve such tasks as planning, goal prioritization, coalition formation, etc. and thus guarantee high levels of UAV autonomy. One of the principal problems in intelligent control system design is tying together various methods and models traditionally used in robotics and aimed at solving such tasks as dynamics modeling, control signal generation, location and mapping, path planning, etc. with the methods of behavior modeling and planning which are thoroughly studied in cognitive science. Our work is aimed at solving this problem. We propose layered architecture—STRL (strategic, tactical, reactive, layered)—of the control system that automates the behavior generation using a cognitive approach while taking into account complex dynamics and kinematics of the control object (UAV). We use a special type of knowledge representation—sign world model—that is based on the psychological activity theory to describe individual behavior planning and coalition formation processes. We also propose path planning methodology which serves as the mediator between the high-level cognitive activities and the reactive control signals generation. To generate these signals we use a state-dependent Riccati equation and specific method for solving it. We believe that utilization of the proposed architecture will broaden the spectrum of tasks which can be solved by the UAV’s coalition automatically, as well as raise the autonomy level of each individual member of that coalition. 相似文献
903.
智能结构三层次理论述评 总被引:2,自引:0,他引:2
近些年来,在认知领域,理论整合的趋势日益强烈,德米特里欧提出了一个关于人类智能结构与发展的“三层次”理论,使人们看到了理论整合令人鼓舞的前景。该理论认为人类智能是一个三层次体系,包括限定了信息加工潜力的加工系统、由一组用以理解不同现实和知识领域的专门化的能力系统组成的环境指向系统以及对这些系统起监控作用的超认知系统。最后,对该理论作了评价。 相似文献
904.
A cut-free Gentzen formulation of the modal logic S5 总被引:1,自引:0,他引:1
905.
906.
This is a purely conceptual paper. It aims at presenting and putting into perspective the idea of a proof-theoretic semantics
of the logical operations. The first section briefly surveys various semantic paradigms, and Section 2 focuses on one particular
paradigm, namely the proof-theoretic semantics of the logical operations.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
907.
908.
In this paper we show that, in Gentzen systems, there is a close relation between two of the main characters in algebraic logic and proof theory respectively: protoalgebraicity and the cut rule. We give certain conditions under which a Gentzen system is protoalgebraic if and only if it possesses the cut rule. To obtain this equivalence, we limit our discussion to what we call regular sequent calculi, which are those comprising some of the structural rules and some logical rules, in a sense we make precise. We note that this restricted set of rules includes all the usual rules in the literature. We also stress the difference between the case of two-sided sequents and the case of many-sided sequents, in which more conditions are needed. 相似文献
909.
建立符合中医特色的科研体系 总被引:2,自引:1,他引:1
比较了中西医产生的社会背景,论述了中医理论的体系具有整体性、重功能、动态性的特点,因而中医科研不能完全套用还原论的方法,必须建立符合中医特色的科研体系,同时还提出中医科研体系具有多维化、信息化、系统化的特点。 相似文献
910.
快感缺乏, 指体验愉快能力的降低, 它在精神分裂症病因学中发挥着很重要的作用, 其存在增加了罹患精神分裂症谱系疾病的风险。然而, 精神分裂症中做情绪体验的快感缺乏研究由于方法学的问题常不能得到一致的结果。从奖励系统入手, 最新的研究证据支持精神分裂症期待性愉快损伤, 而消费性愉快相对完好。在分裂型人格中似乎也存在类似的损伤模式。该文从精神分裂症谱系的角度, 探讨了从奖励系统考察快感缺乏的可能。 相似文献