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81.
为保证铁路安全,讨论了在我国众多的铁路与公路的平交道口设立新型测速 道 口护系统的必要性,提出了8098单片机否则 的构可行性,并且对系统的软件,硬件的主要组成单元进行了分析。  相似文献   
82.
介绍了马钢90tLF-VD(EMS)钢包精炼炉处理车轮轮箍钢的基本工艺情况.工业试验结果表明,在尚未进行真空处理条件下,该工艺使车轮轮箍钢的冶金质量达到国家标准(GB8601-88、GB8602-88)A级产品要求;钢中氧含量最低已达10.70×10-6,平均为15.9×10-6;氧化物夹杂总量平均为0.00175%;钢中硫含量平均0.015%,最低已达0.002%;磷含量平均为0.016%,最低为0.009%,精炼过程无钢水回磷现象;车轮轮箍钢的低温冲击韧性(-40℃、-60℃)与喷粉工艺和普通工艺相比提高了50%以上.讨论了精炼工艺的若干问题.  相似文献   
83.
Knowledge-based system for railway scheduling   总被引:8,自引:0,他引:8  
In this paper, we describe a Knowledge-Based railway scheduling system (called RSS) for Taiwan Railway Administration's (TRA) railway scheduling operations. In our approach, the scheduling process is divided into two levels: global scheduling and local scheduling. In global scheduling, an initial train diagram is established by the Global Scheduler according to the master scheduling plan without considering conflicts. In local scheduling, scheduling conflicts are repaired by Local Scheduler. An embedded knowledge base provides advice for conflict resolution. Since cycles may exist among a sequence of repairs during the repair process, we also propose a cycle detection and resolution scheme in this paper. Through a graphic user interface, the user can interact with the Automatic Scheduler to solve the large-scale complex train scheduling problem in a cooperative and flexible fashion.  相似文献   
84.
区域经济一体化是当今世界的潮流,许多发展中国家建立了所谓的“南-南”型区域一体化组织来推动本国的经济增长;但对于发展中国家经济一体化对经济的影响,有学者认为不利于经济发展,也有学者认为有利于经济发展,本文分析这两种观点,并最终倾向于认为发展中国家实行区域经济一体化有利于发展中国家经济的发展。  相似文献   
85.
Duden T  Gautam A  Dahmen U 《Ultramicroscopy》2011,111(11):1574-1580
This article describes a novel software tool, the KSpaceNavigator, which combines sample stage and crystallographic coordinates in a control sphere. It also provides simulated kinematic diffraction spot patterns, Kikuchi line patterns and a unit cell view in real time, thus allowing intuitive and transparent navigation in reciprocal space. By the overlay of experimental data with the simulations and some interactive alignment algorithms, zone axis orientations of the sample can be accessed quickly and with great ease. The software can be configured to work with any double-tilt or tilt–rotation stage and overcomes nonlinearities in existing goniometers by lookup tables. A subroutine for matching the polyhedral shape of a nanoparticle assists with 3D analysis and modeling. The new possibilities are demonstrated with the case of a faceted BaTiO3 nanoparticle, which is tilted into three low-index zone axes using the piezo-controlled TEAM stage, and with a multiply twinned tetrahedral Ge precipitate in Al, which is tilted into four equivalent zone axes using a conventional double-tilt stage. Applications to other experimental scenarios are also outlined.  相似文献   
86.
《Soils and Foundations》2019,59(6):2238-2253
The increased generation of demolition waste has led to the successful implementation of its utilization in civil engineering projects. The combination of recycled aggregates and supplementary materials can potentially improve the quality of geomaterials when constructing alternative railway capping layers. In this research, two types of demolition waste, namely, Recycled Concrete Aggregates (RCA) and Crushed Brick (CB), were studied in comparison to two Conventional Capping Materials (CCMs), which are currently used for railway track construction. Recycled Glass (RG) and Mixed Recovered Plastic (MRP) were also blended with RCA to assess their performance. All the materials and mixtures were evaluated in terms of both stiffness and strength. A new Repeated Load Triaxial (RLT) testing protocol was introduced based on the stress induced in the capping layers to determine the stiffness of the materials. A comparison was made among the current resilient modulus prediction models to find a model that would better fit the results for the demolition waste and mixtures. Multistage triaxial tests were also conducted to determine the strength, friction, stiffness and energy absorption capacity of the materials. It was found from this research study that RCA, CB and mixtures of RCA with RG and MRP have equivalent or higher levels of stiffness and strength than CCMs and are suitable alternatives for sustainable railway capping layer construction.  相似文献   
87.
The West Coast Region (WCR) of the Western Cape Province in South Africa is earmarked for 13 onshore wind farm projects totaling approximately 700 wind turbines. The developed world debate about the social acceptance of wind farm projects has impeded and illuminated a number of these developments. This paper is aimed at understanding people's reaction to proposed wind farm projects in the WCR – a region of a developing country – and to investigate whether the reasoning behind opposition to or acceptance of wind farm projects is similar to the discourse on the topic by scholars in the developed world. Quantitative and qualitative methods were used to collect primary data by semi-structured interviews and a questionnaire survey. A spatial dimension was added through a map-based approach. Reactions by WCR residents to the wind farm projects were mainly positive, although some opposition was detected. International scholarship holds that place attachment serves as a reason for opposition to wind farm projects. Although most of the WCR residents had strong place attachments to their region, most of the respondents also supported the proposed wind farm projects.  相似文献   
88.
89.
To develop a low cost and highly effective metallurgical route for solar-grade Si production, we investigated the zone melting directional solidification method. In this method, bulk crystalline Si is successfully produced from Si-Sn solvent; this bulk crystalline Si demonstrates a steady growth interface and excellent compositional uniformity. Moreover, the growth rate of bulk crystalline Si along the axial direction increases because the remaining MG-Si serves as Si source to keep the Si-Sn solution saturated with Si atoms, and it is approximately three times larger than that of Si by using the Si-based alloy directional solidification method without Si source. In this work, the evolution of impurity phases segregated in different regions along the axial direction is extensively discussed. The distribution and amount of impurities, including Ca, Al, B, and P, are effectively controlled by this refining method, further improving the quality of bulk crystalline Si.  相似文献   
90.
在压水堆LOCA(Loss of Coolant Accident)事故之后,高能管道流体喷射冲击导致破口附近的保温层等材料破裂为碎片。这些碎片随流体在安全壳内传输并在地坑滤网沉积形成碎片床,阻碍应急堆芯冷却系统的正常运行。部分碎片可能旁通滤网进入反应堆压力容器,从而引起一系列的效应。该问题被称之为GSI-191(Generic Safety Issue-191)问题。为解决GSI-191问题,首先需要确定破口附近产生的碎片量。当前研究基于ANSI/ANS58.2-1988标准和等效体积球体模型,自主开发了喷射冲击影响区域计算工具JETZOI。采用该工具计算获得的NEI(Nuclear Energy Institute)算例的喷射轮廓和等压线与美国核管会(United States Nuclear Regulatory Commission,U.S NRC)的结果符合很好,从而实现了对NEI算例的成功复现。进一步进行了不同滞止工况的敏感性分析。分析结果表明,在相同的滞止压力下,流体温度的升高将导致影响区域破坏半径的减小和碎片量的减少。因此在开展喷射冲击试验获得影响区域的破坏半径时,应当保守选取冷段双端断裂作为极限工况以使喷射冲击产生的碎片量最大。  相似文献   
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