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1.
工业遗产保护在当今城市规划与建设中占据重要地位,需要注重与城市整体脉络相协调,又要注重再利用和可持续发展。针对无锡西漳蚕种场工业遗产保护性再利用进行研究分析,最大限度保存场内部分建筑历史痕迹,寻求各建筑之间的连贯性、通透性、形成统一丰富的空间。复原并扩大桑田规模并与景观融为一体,形成统一的整体。最终解决蚕种场工业历史建筑与景观面临衰败的问题,使工业遗产开发与教育、旅游开发相结合,找出工业历史建筑自身生存的问题以及可持续发展的对策。  相似文献   
2.
Integration of electric vehicles (EVs), demand response and renewable energy will bring multiple opportunities for low carbon power system. A promising integration will be EV battery swapping station (BSS) bundled with PV (photovoltaic) power. Optimizing the configuration and operation of BSS is the key problem to maximize benefit of this integration. The main objective of this paper is to solve infrastructure configuration of BSS. The principle challenge of such an objective is to enhance the swapping ability and save corresponding investment and operation cost under uncertainties of PV generation and swapping demand. Consequently this paper mainly concentrates on combining operation optimization with optimal investment strategies for BSS considering multiscenarios PV power generation and swapping demand. A stochastic programming model is developed by using state flow method to express different states of batteries and its objective is to maximize the station’s net profit. The model is formulated as a mixed-integer linear program to guarantee the efficiency and stability of the optimization. Case studies validate the effectiveness of the proposed approach and demonstrate that ignoring the uncertainties of PV generation and swapping demand may lead to an inappropriate batteries, chargers and swapping robots configuration for BSS.  相似文献   
3.
To coordinate the protection of PMSG (permanent magnet synchronous generator), collector circuits and outgoing lines, a comprehensive and improved protection method of PMSG based wind farms with LVRT (low voltage ride through) capability is proposed. The proposed method includes adding a short time delay to the collector network current protection zone I and a directional protective relaying to the collector network protection, installing grounding transformers and zero sequence current protection, and generator low-voltage protection action improvement. A LVRT scheme consisting of variable resistance dumping circuit, grid side dynamic reactive power control and reactive power compensation control is proposed. The fault characteristics of PMSG based wind farms are analyzed, and a PMSG based wind farm in Dabancheng, Xinjiang, is used as an example to analyze typical wind farm protection configuration, the setting values considering LVRT requirements, and the coordination problems. Finally, an improved wind farm protection coordination methodology is proposed and its validity is verified by simulation.  相似文献   
4.
The way a model is designed to assist farmers in their decision-making may influence how it is understood and perceived by farmers and shape interactions between farmers and model users (researcher, advisor). This study compared the strengths and weaknesses of three types of whole farm models used by researchers to assist 18 crop-livestock farmers in Burkina Faso in planning the next agricultural season. Due to its simplicity, the static simulation tool of annual farm stocks and flows led to superior changes in the farmers' knowledge and practices. The rule-based dynamic simulation tool helped the researchers grasp farmers' decision-making processes but was difficult for farmers to understand due to the discrepancy between its multi-annual time step and the farmers' short-term planning horizon. The optimisation tool stimulated more strategic discussions regarding paths to improve farm income despite a design that was distant from the farmers' reality.  相似文献   
5.
A review of milking machine tests on 640 dairy farms in England and Wales between 2012 and 2014 suggests more machines now comply with installation and operation standards than 10 years ago. However, approximately 60% of systems tested failed to meet the milking machine requirements of the farm assurance standards in the UK, with most failing to reach operational requirements on one aspect. The most common problem (47%) was that the systems had excessive vacuum line losses, with other vacuum/airline losses also common. Many machines failed on more than one aspect.  相似文献   
6.
Over the last four decades, the onset of computation has enabled architects and designers to employ generative patterns in their exploration of emergent social, material and spatial systems. Theodore Spyropoulos provides an overview of the field and discusses how it has been developed by the Design Research Lab (DRL) at the Architectural Association into an ‘Adaptive Ecologies’ agenda. In the context of parametric urbanism, the DRL has explored models of living through behavioural patterns found in nature, examining the role of the singular and the collective. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
7.
Felicity D Scott , Associate Professor of Architecture at Columbia University Graduate School of Architecture, Planning and Preservation (GSAPP), describes here the instant city events of the early 1970s. These foreshadowed current global village media practices in what now seems a quaintly material manner: communication between sites involved the physical mailing of videotapes and ‘wire photos’ through the postal service. The sites themselves – in the US and elsewhere – were transformed into ‘instant cities’ through the erection of physical geodesic domes, teepees and inflatables in seas of mud. The true antecedents of today's instant networking, these pioneers embraced the newest technology available at the time and the most innovative forms of temporary architecture.  相似文献   
8.
本文介绍了一种新型复合管材———HDPE筋塑管的特点 ,并与其它管材进行了比较 ,给出了目前的应用领域 ,最后具体介绍了农田灌溉工程中应用的施工过程 ;结论是HDPE筋塑管是一种性能良好、应用前景广泛、与其它管材相比有很强的经济性的管材  相似文献   
9.
Surveys have been conducted, under the auspices of the Ministry of Agriculture and Agricultural Development Projects (ADPs), in the 23 local-government areas of the Rivers State, Nigeria. A structured questionnaire, personal visits to farms and interactions with information repositories were used. The quantities of energy consumed by tractors used in activities associated with the growing of cassava and yam crops in those areas were compared with traditional operations, using just manual labour. Within the period of 1986–2004, the total energy utilizations in the production of these crops, in the 23 local government areas, were 2738.87 and 33.5 MJ for tractor-power and traditional-manual operations, respectively. The tractorization intensity (TI) dropped from 0.352 hp/ha in 1986 to 0.345 hp/ha in 2004. This result was below the presently advocated 0.5 hp/ha for agricultural operations in order to increase crop production. This study identified the causes of this shortfall and recommended, at least for the short-term future, that farm industrialization of all sectors should be subsidized.  相似文献   
10.
乔治·奥威尔在他的小说《动物庄园》中,运用黑色幽默手法,将一个极权、泯灭人性的未来社会面貌通过拟人的寓言形式表现出来.其中,讽刺、角色选择时代性、语言的谬论手法,体现黑色幽默的艺术技巧.  相似文献   
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