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961.
针对侦察效能评估中,指标因素的多样性和因素间的复杂关系,依据主成分分析的评估思路,运用BP神经网络对侦察效能进行评估.结合BP神经网络的逼近非线性函数的映射能力和并行处理的特点,解决数据样本的分类问题.通过对侦察效能的评估,验证了BP神经网络对效能评估的可行性,其方法和成果可供其它武器装备效能评估借鉴和参考.  相似文献   
962.
根据钢筋混凝土结构的可分性,将钢筋混凝土结构分为梁、板、柱、地基基础、围护系统和结构整体性6个相对独立的部分。结合专家经验和已有研究成果,按照各自的准则和指标,构造各项目隶属函数来描述其可靠性的分级,建立各项目模糊关系矩阵。根据层次分析法原理,确定影响其可靠性的各因素权重,提出了钢筋混凝土结构可靠性模糊综合评估新方法。该评估使已有建筑物可靠性鉴定工作更加合理,并为建立相应的专家系统奠定了基础。  相似文献   
963.
This paper investigates the links between public transport and labor market outcomes in the French agglomeration of Bordeaux. Our objective is to analyze the effects and consequences of the construction of a tramway line in some neighborhoods and municipalities of the agglomeration. These localizations are confronted to isolation and concentration of unfavorable socio-economic characteristics. Among other things, this line has permitted to facilitate the access to the historical job center of Bordeaux for inhabitants concerned. We use difference-in-differences methods to compare labor market outcomes of inhabitants who benefit from this better access with others who do not, before and after the construction. Results show that if unemployment rate has globally decreased on the period observed, the decrease is more important for neighborhoods located close to tramway stations. More generally, it seems that the tramway project helped to reduce some socio-economic inequalities in the agglomeration of Bordeaux.  相似文献   
964.
伴随高等教育大众化进程,我国高校逐步进入以质量取胜的内涵式发展阶段,质量成为高等院校赖以生存与发展的生命线,尤其是高职院校人才培养质量遭受质疑,在新的时代背景下高职教育如何从大变局和新占位视域跳出传统思维定式走向理性。教师教学质量评价作为高校一项常规性工作,不只是一个管理工具和评价手段的应用,而是关乎人才培养质量的管理与生成,集中体现为学生需求满足程度的价值判断过程,其根本目的在于提高人才培养质量。本文基于生本视角,从问题缘起、理论探源及结构要素三个逻辑层面重视高校教师教学质量评价,深刻回答教师教学质量评价"为什么、是什么、怎么样"的元生逻辑问题,以期从学理层面厘清教师教学质量评价的本质内涵和应然之义,科学指导实践。  相似文献   
965.
The drive to reduce fuel consumption and greenhouse gas emissions is one shared by both businesses and governments. Although many businesses in the European Union undertake interventions, such as driver training, there is relatively little research which has tested the efficacy of this approach and that which does exist has methodological limitations. One emerging technology employed to deliver eco-driving training is driver training using a simulator. The present study investigated whether bus drivers trained in eco-driving techniques were able to implement this learning in a simulator and whether this training would also transfer into the workplace. A total of 29 bus drivers attended an all-day eco-driving course and their driving was tested using a simulator both before and after the course. A further 18 bus drivers comprised the control group, and they attended first aid courses as well as completing the same simulator drives (before-after training). The bus drivers who were given the eco-driving training significantly improved fuel economy figures in the simulator, while there was no change in fuel economy for the control group. Actual fuel economy figures were also provided by the bus companies immediately before the training, immediately after the training and six months after the training. As expected there were no significant changes in fuel economy for the control group. However, fuel economy for the treatment group improved significantly immediately after the eco-driving training (11.6%) and this improvement was even larger six months after the training (16.9%). This study shows that simulator-based training in eco-driving techniques has the potential to significantly reduce fuel consumption and greenhouse gas emissions in the road transport sector.  相似文献   
966.
There are many systems to evaluate driving style based on smartphone sensors without enough awareness from the context. To cover this gap, we propose a new system namely CADSE system to consider the effects of traffic levels and car types on driving evaluation. CADSE system includes three subsystems to calibrate smartphone, to classify the maneuvers, and to evaluate driving styles. For each maneuver, the smartphone sensors data are gathered in three successive time intervals referred as pre-maneuver, in-maneuver, and post-maneuver times. Then, we extract some important mathematical and experimental features from these data. Afterwards, we propose an ensemble learning method on these features to classify the maneuvers. This ensemble method includes decision tree, support vector machine, multi-layer perceptron, and k-nearest neighbors. Finally, we develop a rule-based fuzzy inference system to integrate the outputs of these algorithms and to recognize dangerous and safe maneuvers. CADSE saves this result in driver’s profile to consider more for dangerous driving recognition. The experimental results show that accuracy, precision, recall, and F-measure of CADSE system are greater than 94%, 92%, 92%, and 93%, respectively that prove the system efficiency.  相似文献   
967.
Strategic Environmental Assessment (SEA) is one of the most important instruments for making relevant decisions on the basis of which spatial planning is aligned with the tenets and principles of sustainable spatial development. Its primary application is in spatial (strategic) and urban planning, as well as in the planning and design of sectoral policies in the areas of energy, water management, waste management, transport, etc. The implementation of SEA allows developers to establish the benefits and implications of the proposed spatial changes, taking into account the capacity of the space to sustain the planned development, and to determine the degree of acceptability of the proposed spatial changes. This paper presents a specific method of assessing the impact of airport noise as part of a particular SEA. The particularity of this method is that it integrates the objectives, indicators and criteria for assessing the impact of airport noise on the population using the method of multi-criteria evaluation, applied in the preparation of the SEA for the Urban development plan regarding the expansion of Tivat Airport, Montenegro. The changes in noise intensity within the planning horizon to 2030 were predicted taking into account the following factors: physical, geographic and demographic characteristics of the space, the projected increase in the number and nature of the flights operated within the planning period, as well as the types of aircraft. On the basis of these data noise dispersion modelling was carried out using the IMMI model, and the results obtained were used in a multi-criteria evaluation as part of the SEA. The results of the research do not indicate any significant increase in noise intensity within the planning period to 2030 and they represent a good basis for making relevant decisions regarding the future development of Tivat Airport.  相似文献   
968.
钢纤维与混凝土水泥石基体界面性能直接决定纤维对复合材料的增强效果,对界面性能的改善已经成为钢纤维混凝土性能提高的主要途径。从界面区的结构与特征着手,总结国内外界面区力学性能与微观结构的测试方法和评价指标,阐述常用的纤维混凝土理论及一些有限元模拟分析方法,并对钢纤维混凝土发展方向进行归纳。  相似文献   
969.
针对70 m预制箱梁混凝土早期抗压强度及耐久性的需求,通过调整胶凝材料的用量以及掺合料的掺配比例,进行多次试配、试验,配制出满足东南沿海地区不同季节气候条件下箱梁混凝土施工工艺需求的海工耐久混凝土配合比。  相似文献   
970.
杜志刚  梅家林  倪玉丹  陈逸飞 《隧道建设》2020,40(11):1558-1569
总结城市水下道路隧道事故分布规律,从驾驶人、隧道光环境及道路条件3方面分析隧道驾驶安全影响因素,对现有安全改善措施及其优缺点进行剖析,并指出城市水下道路隧道驾驶安全优化研究趋势: 应以提升隧道光环境质量为主,考虑交通事故形态、事故致因及影响因素,在确保交通安全的基础上,考虑不同隧道路段驾驶人差异化视觉需求。驾驶人视觉需求可以分为功能性、安全性与舒适性需求,对应的隧道行车环境可分为基本型、安全型与舒适型视觉参照系。提出以构建城市水下道路隧道舒适型视觉参照系为目标,通过隧道照明与隧道视线诱导技术相结合,缓解隧道出入口参照系的剧烈过渡,加强中间段弱视觉参照的城市水下道路隧道驾驶安全优化方法。构建基于空间路权、人因与驾驶任务、差异性与韵律性的隧道驾驶安全优化评价指标体系,为城市水下道路隧道驾驶安全优化提供新思路。  相似文献   
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