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991.
近年来各类农业园区建设日益增多,本文试图通过具体案例对以产业为主的现代农业园区的规划进行剖析,主要从现状分析、规划设计和运行情况三方面进行论述,试图对这类园区的规划特点进行总结和提炼,以便从规划角度探索该类园区长远发展的规划模式。 相似文献
992.
针对如何提高旧桥的承载能力和行车性能这一问题,从项目前期规划与方案构思的角度入手,介绍了桥梁加固维修项目规划流程,阐述了桥梁加固维修项目规划应遵循的原则和注意事项,并得出了一些有益的结论。 相似文献
993.
Tsai Jessica Chia-Chin; Knoblich Günther; Sebanz Natalie 《Canadian Metallurgical Quarterly》2011,37(5):1407
According to ideomotor theories, perceiving action effects produced by others triggers corresponding action representations in the observer. We tested whether this principle extends to actions performed by externally controlled limbs and tools. Participants performed a go–no-go version of a spatial compatibility task in which their own actions resulted in the movement of a limb or tool, whereas a second, externally controlled limb or tool was seen performing a complementary go–no-go task. Spatial compatibility effects, indicating inclusion of the externally controlled effector in action planning, were observed when the externally controlled limb was identical to the controlled limb (Experiment 1) and when actions of limbs and tools (Experiment 2) or pairs of tools (Experiment 3 and 4) were combined according to participants' motor experience. When participants acted together, controlling a tool each, spatial compatibility effects occurred regardless of motor experience (Experiment 5). These findings demonstrate that (a) externally controlled tool actions are included in action planning and (b) social context modulates how externally controlled actions are mapped onto action representations. Implications of these findings for theories of perception–action links and object processing are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
994.
Coverage path planning for UAVs based on enhanced exact cellular decomposition method 总被引:3,自引:0,他引:3
In this paper, an enhanced exact cellular decomposition method to plan the coverage path of UAVs in a polygon area is proposed. To be more specific, the contributions of the paper are: firstly, the turning motion of UAVs is shown to be less efficient from the viewpoints of route length, duration and energy. Secondly, the problem of coverage Path Planning (CPP) in a convex polygon area is transformed to width calculation of the convex polygon, and a novel algorithm to calculate the widths of convex polygons with time complexity of O(n) is developed. The path of the least number of turns for an UAV based on the widths of convex polygons is devised. Thirdly, a convex decomposition algorithm for minimum width sum based on the greedy recursive method which revolves around decomposing the concave area into convex subregions is developed. It is proved that the algorithm is a polynomial time algorithm. To avoid unnecessary back and forth motion, some entirely adjacent subregions are combined. Finally, comparing different weights of two joint-points, a subregion connection algorithm based on minimum traversal of weighted undirected graph is proposed to connect the coverage paths of the subregions. Simulation results show that the proposed method is feasible and effective. 相似文献
995.
Andrzej Banaszuk Vladimir A. Fonoberov Thomas A. Frewen Marin Kobilarov George Mathew Igor Mezic Alessandro Pinto Tuhin Sahai Harshad Sane Alberto Speranzon Amit SuranaAuthor vitae 《Annual Reviews in Control》2011,35(1):77-98
Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to uncertain dynamical systems, we will also show examples of application of the new methods to efficient uncertainty quantification of energy usage in buildings, and stability assessment of interconnected power networks. 相似文献
996.
Kinematic redundancy of a pair of manipulator-task can be classified into intrinsic and functional redundancies. With the help of redundancy, the manipulator is able to approximate a secondary task while completing the main task. However, the success of the redundancy resolution relies on a proper choice of weights, that plays an important role in balancing the different components of the secondary task. In order to ensure the fulfillment of both the main and secondary tasks, the weights have to be tuned for each given manipulator-task. In this paper, a self-adaptation system is presented in replacement of the low-effective manual tuning of weights. The self-adaptation system is integrated into the twist decomposition algorithms, and is successfully applied to the examples of joint-limits and singularity avoidances as secondary task. 相似文献
997.
结合实际工程,介绍了该应用的具体步骤。通过对工程的分析,绘制了网络图,找到了关键线路,并对工程计划进行了优化。 相似文献
998.
Takaya Yamamoto Tomihiro Takano Yoshiyuki Takuma Makoto Inoue Gen Arao 《Electrical Engineering in Japan》2010,170(3):19-27
Dispersed generators such as wind power systems, photovoltaic systems, and cogeneration systems are expected to mitigate the environmental burden of energy consumption, and their installation has been promoted recently. Micro‐Grid is focused on as a method to solve some problems in a commercial electric power line when installing a large number of dispersed generators, and some demonstrative research on Micro‐Grid for large‐scale systems is being carried out now. Also, small cogeneration systems for houses, such as gas engines and fuel cells, are expected to improve CO2 emissions. However, if the power and heat demand of a family are relatively small or are unbalanced, the cogeneration system does not operate effectively. The authors have studied the application of Micro‐Grid for home energy supply, and have developed a control system to solve this problem. The system achieves a reduction of CO2 emissions and energy costs by sharing electric power and heat among some houses with cogeneration systems. This paper presents an outline of the newly developed system, and in particular describes the effect of the reduction in CO2 emissions compared with a conventional energy supply method, and the case in which dispersed generators are installed in some houses and operate independently. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(3): 19–27, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20879 相似文献
999.
Yasminah Beebeejaun 《Planning Theory & Practice》2013,14(4):437-451
Targeted consultation of ethnic minority groups has been promoted as a tool to address systemic racial disadvantage within society. Within planning there has been an emphasis upon identifying ethnic minority communities in the context of considering differing policy needs within the development planning process. The article draws upon research investigating how the ideology of the nation constructs ethnicity which acts to shape consultation practices within local planning authorities in England. The development of such consultation within urban planning, it is argued, has reinforced false understandings of ethnicity. Despite good intentions in some respects, planning authorities continue to address the needs and interests of ethnic minority people in a superficial manner. The article suggests that there is a need to give greater attention to how the ideology of the nation limits the actions of planners. 相似文献
1000.
August E. RØsnes 《Planning Theory & Practice》2013,14(1):35-51
Planning changes can be initiated formally through revisions of statutory rules; alternatively changes can arise informally through amendments to everyday planning activities. This article explains how local planning authorities in Norway introduce new planning practices relating to the management of land and planning procedures. The observed new practices have been introduced even though the formal hierarchical structure of the planning law has stayed unchanged. They are analysed as outcomes of the changing use of tools under the three models for co-ordinating behaviour: hierarchy understood as government, market and network. First, the existing planning system is analysed to explain the legal possibilities for changing planning practices informally. Two categories of practices are then discussed: the use of the detailed development plan as an implementation instrument, and the use of the regulatory power in framing interconnections and responsibilities towards stakeholders. The main conclusion is that regulatory tools have lost some strength in favour of tools under the network model, and that the observed changes in planning practices are mostly a result of mutual dependencies between these two models for co-ordinating behaviour. 相似文献