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41.
“Big data” which admittedly means many things to many people is no longer confined to the realm of technology. Today it is a business imperative and is providing solutions to long-standing business challenges for banking and financial markets companies around the world. Financial services firms are leveraging big data to transform their processes, their organizations and the entire industry. Since 2012, the term “big data” has frequently been mentioned and used to describe and define the huge amount of data in the information explosive era and to name related technological development and innovation. As to the police work, the coming of big data era is not only a challenge but also an opportunity. Police agencies should go with the tide of development to start with such aspects as work thinking, top design, public information sharing and application and talent provision so as to promote the new development and progress of police work. This paper expounds the practical effect and significance of police big data application by cases happened in some areas.  相似文献   
42.
Optimizing bus-size and headway in transit networks   总被引:1,自引:0,他引:1  
Optimization models for calculating the best size for passenger carrying vehicles in urban areas were popular during the 1980s. These studies were abandoned in the ‘90s concluding that it was more efficient to use smaller buses at higher frequencies. This article returns to this controversial question, starting from the point of view that any calculation of bus size can only be made after considering the demand for each of the routes on the system. Therefore, an optimization model for sizing the buses and setting frequencies on each route in the system is proposed in accordance with the premises detailed below. The proposed model is a bi-level optimization model with constraints on bus capacity. The model allows buses of different sizes to be assigned to public transport routes optimizing the headways on each route in accordance with observed levels of demand. At the upper level the model considers the optimization of the system’s social and operating costs, these are understood to be the sum of the user’s and operator’s costs. At the lower level there is an assignment model for public transport with constraints on vehicle capacity which balances the flows for bus sizes and headways at each iteration. By graphically representing the results of the model applied to a real case, a series of useful conclusions are reached for the management and planning of a fleet of public transport vehicles.  相似文献   
43.
For the impact of intermittent resources’ high penetration on the economic dispatch of islanded microgrid, a new economic dispatch method is presented to minimize the overall generating cost for islanded microgrid, considering a cooperative strategy between diesel generator (hereinafter referred to as DE) and battery energy storage system (BESS). The optimum economic operation range of DE and the optimal set-point between DE and BESS are presented in the cooperative dispatch strategy, in which BESS is used fully to enable DE in a lower cost and higher efficient way. The results are analyzed under various operation conditions and also prove the validity of the proposed method.  相似文献   
44.
高速铁路夕发朝至列车开行与天窗设置存在动态影响关系,将两者进行协同优化有助于满足旅客夜间出行需求,提升铁路运力资源配置.?以通道型高速铁路为对象,在分析高速铁路夕发朝至列车与天窗设置影响关系的基础上,以高速铁路夕发朝至列车总的旅行时间最少和高速铁路夕发朝至列车的开行对既有列车运行图的影响最小为目标,建立了列车开行模式未...  相似文献   
45.
The operating principle and specifications of a laser meter for measuring hydrosphere pressure variations are described in this article. The meter was designed to measure the hydrosphere pressure variations to a depth of 500 m within the frequency range of 0–1000 Hz at the level of background oscillations. Some results obtained using the apparatus under consideration when recording sea oscillations and waves of natural and artificial origin are presented.  相似文献   
46.
将模糊综合评判应用于鱼雷武器系统作战效能评估中,定量分析并处理评估中的模糊性问题。在建立评估指标体系的基础上,构建二级模糊综合评判模型,对指标进行综合评价,求出评价等级量化值。模型计算结果证明该方法具有较好的可行性。  相似文献   
47.
Coastal and marine areas provide vital services to support the economic, cultural, recreational, and ecological needs of human communities, but sustaining these benefits necessitates a balance between growing and often competing uses and activities. Minimizing coastal zone conflict and reducing human-induced impacts to ecological resources requires access to consistent spatial information on the distribution and condition of marine resources. Seafloor mapping provides a detailed and reliable spatial template on the structure of the seafloor that has become a core data need for many resource management strategies. The absence of detailed maps of the seafloor hinders the effectiveness of priority setting in marine policy, regulatory processes, and marine stewardship. For large management areas, the relatively high cost of seafloor mapping and limited management budgets requires careful spatial prioritization. In order to address this problem, a consensus based approach, aided by decision-support tools, and participatory geographic information systems (GIS), was implemented in Long Island Sound to spatially prioritize locations, define additional data collection efforts needed, and identify products needed to inform decision-making. The methodology developed has utility for other states and regions in need of spatially prioritizing activities for coastal planning, and organizations charged with providing geospatial services to communities with broad informational needs.  相似文献   
48.
哈齐高速铁路穿越高寒地区,铁路扣件保持轨距的能力对于运营安全和运营成本非常重要。铁路扣件绝缘轨距块以玻璃纤维(33%含量)增强聚酰胺66体系(PA66-GF33体系)作为原材料,在原材料中添加增韧剂来改善绝缘轨距块低温下的力学性能。本文研究增韧剂(马来酸酐接枝三元乙丙橡胶)含量变化对PA66-GF33体系在常温下力学性能的影响,及其在-30℃和-50℃环境下缺口冲击强度的变化。研究结果表明:原材料中增韧剂含量由3%增加到12%时,缺口冲击强度增大,拉伸强度、弯曲强度和熔融指数降低,扫描电镜分析显示缺口冲击试验的样条断面由脆性断裂逐渐表现为韧性断裂;当增韧剂含量为6%时,PA66-GF33体系同时具有较好的低温韧性和优良的加工性能,选择增韧剂含量为6%的PA66-GF33体系作为绝缘轨距块原材料,采用注塑工艺制备的绝缘轨距块剖面无内部空隙,并且在-45℃环境下冲击强度试验合格。  相似文献   
49.
桥梁在地震中的碰撞反应不容忽视,文章综述了国内外桥梁地震碰撞的模拟方法以及各种形式桥梁结构的地震碰撞近期研究进展,归纳了桥梁碰撞的条件和影响因素,介绍了减轻桥梁结构地震碰撞方法和防落梁措施的主要研究成果,并对桥梁地震碰撞反应的进一步研究作了展望。  相似文献   
50.
杨璨  韩金刚  安鸿  肖维远  刘苹 《铁道车辆》2021,(1):97-101,109
货车空气制动系统因防尘不良导致内部清洁度差,影响制动系统性能。文章针对这一问题进行了防尘技术研究,通过调研和分析,识别出2个防尘不良点和8个污染物来源,针对防尘不良点及污染物进行了结构改进。改进后的货车制动系统防尘效果明显提升。  相似文献   
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