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目的 破解特殊自然环境影响产生的某型地面武器系统保障难题。方法 根据历史故障情况,采用FMEA(Failure Mode Effect Analysis,故障模式影响分析)进行低温影响分析,采用Pearson相关系数法分析低温与武器系统故障关系,应用回归分析进行严寒条件下装备故障情况预测。结合实际应用情况,全面系统总结该型地面武器系统在严寒条件下,使用和保障过程中可能出现的技术准备、性能指标、信息体系构建、伪装防护、维修保障相关问题。结果 得出某型地面武器系统低温情况下故障数量与温度负相关的结论,且预测在严寒条件下该型武器系统故障数量将大幅上升。通过总结保障经验,有针对性地提出了配置地域、物资筹措、安全运输、维护保障、维修训练等方面的对策措施。结论 根据作战任务的等级转换、机动输送、战前集结、战斗抗击和战后总结等环节,提出装备保障流程建议,以提高严寒地区某型地面武器系统保障效能。 相似文献
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地理信息系统在环境模型研究中的应用 总被引:45,自引:2,他引:43
结合国内外环境信息系统的研究现状和研究实例,首先分析了GIS与环境模型研究结合的必要性和GIS在环境模型研究中潜在的应用范围,然后剖析了GIS与环境模型研究结合的三阶水平并介绍了GIS在环境模型研究中的应用现状,最后分析了GIS和环境模型研究结合的发展趋势并给出了GIS、RS、ES与环境模型理想的结合框架。 相似文献
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C.Y. Ng K.B. Chuah Alex Pui-yuk King 《International Journal of Sustainable Engineering》2019,12(2):108-114
Environmental impacts have become an important consideration in the manufacturing industry due to increasing public pressure for environment protection and the requirements of recently launched legislations. Data envelopment analysis (DEA) is a widely adopted methodological approach for the benchmarking of the relative efficiency of different production units. Changes in production efficiency may affect environmental impacts. DEA can be used for identifying the most efficient production facility and hence, the environmental impacts generated from the different production lines can then be benchmarked. Life cycle assessment (LCA) is carried out to quantify the full environmental impacts of a product from ‘cradle to grave’. The integration of LCA with DEA, efficiency and environmental impact of different production processes for a certain family of products can be evaluated and benchmarked. The proposed two-stage approach can help to reduce the aggregate environmental impacts of the manufacturing phase and is used to benchmark the environmental performance of several production lines in a manufacturing company. 相似文献
427.
Preparedness of emergency evacuation for the leakage of toxic substances in chemical plants is very important in order to reduce damage. In order to implement an emergency evacuation properly, it is necessary to comprehensively and concretely determine the conditions of the leakage and atmospheric conditions and predict the consequences of the dispersed gases. Repeated training for emergencies is also essential. In order to realize effective evacuation, a prediction model of the evacuation area that anyone can use to obtain the same results both accurately and promptly is developed in the present study. The prediction model is designed such that the wind speed and atmospheric conditions are automatically set, and the leakage rate is the only input parameter, so that anyone can use the model easily. In addition, the model can also predict the atmospheric parameters for up to 3 h and can calculate the evacuation distance so that smooth evacuation can be achieved for changing atmospheric conditions. Finally, the evacuation area is defined by statistically analysed wind fluctuations, and a series of emergency evacuation measures is implemented. 相似文献
428.
为了研究孔隙水压力作用下深埋隧道掌子面的稳定性,构建了深埋盾构隧道的二维刚性有限平动多块体的破坏模式,并引入了Hoek Brown强度准则。利用极限分析得到掌子面前方土体的内部耗散能和外力做的功,利用Hoek Brown强度准则推导得到极限支护力的目标函数,通过MATLAB数值软件的规划求解得到支护力的解,和既有文献中的成果对比,2种方法得到解的最大误差为6.7%,验证了Hoek Brown强度准则的有效性。对各个岩体参数下深埋隧道掌子面极限支护力的变化规律进行分析,结果表明:深埋隧道掌子面前方的极限支护力随着扰动因子D和孔隙水压力系数ru的增大而增大,随着地质强度指标GSI和参数mi的增大而减小;破坏范围随着参数mi和孔隙水压力系数ru的增大而减小,而随着地质强度指标GSI和扰动因子D的增大而增大。研究结果可为岩质地层中深埋盾构隧道掌子面支护力的设计提供理论依据。 相似文献
429.
Ashfaq Ahmad Changan Zhu Iqra Javed M. Waqar Akram Noman Ali Buttar 《International Journal of Green Energy》2020,17(3):219-232
ABSTRACTThe uncertainty in the output power of the photovoltaic (PV) power generation station due to variation in meteorological parameters is of serious concern. An accurate output power prediction of a PV system helps in better design and planning. The present study is carried out for the prediction of output power of PV generating station by using Support Vector Machines. Two cases are considered in the present study for prediction. Case-I deals with the prediction of PV module parameters such as Voc, Ish, Rs, Rsh, Imax, Vmax, Pmax, and case-II deals with the prediction of power generation parameters such as PDC, PAC, and system efficiency. Historical data of PV power station with an installed capacity of 10 MW and weather information are used as input to develop four different seasons-based SVM models for all parameters. The performance results of the models are presented in terms of Mean Relative Error (MRE) and Root Mean Square Error (RMSE). Additionally, the performance results obtained with polynomial and Radial Based Function kernel are also compared to show that which kernel has better prediction accuracy, and practicability. The result shows that the minimum average RMSE and MRE for case-I with Radial Based Function kernel are 0.034%, 0.055%, 0.002%, 1.726%, 0.044%, 0.047%, 2.342%, and 0.005%, 0.014%, 0.079%, 0.885%, 0.005%, 0.007%, 0.013%, and for case-II with poly kernel are 0.014%, 0.016%, 0.149% and 0.011%, 0.0175, 1.03%, respectively. The present study will be helpful to provide technical guidance to the prediction of the PV power System. 相似文献
430.
Juan Arteaga Pablo Ochoa Andreas Fries Jan Boll 《Journal of the American Water Resources Association》2020,56(2):270-282
Integrated watershed management (IWM) is a priority, especially in semiarid regions that are concurrently affected by population growth, land use change, soil erosion, and poor governance. In developing countries, IWM is often done without any support tool, scientific data, or deep knowledge of territory characteristics. The aim of this study was to present a case study to apply a decision support tool to prioritize areas for territory management. A simple, quantitative multi‐criteria analysis was applied in a semiarid basin of the Ecuadorian Andes to identify the zones of greatest concern for implementation of resource conservation and management practices at a local and regional scale. In addition to describing the current state of the conditions of this basin, our results suggest scenarios of change in relation to official population projections based on spatial analysis of land use change. Analysis resulted in a scattered distribution of priority values within the watershed, so a hierarchical rule was incorporated to define priorities at the subwatershed (SW) scale. Our analysis identified four SW of very high priority and urgent need to implement management practices. Based on projections of future change due to population growth and land cover change, the number of subbasins that require more attention was doubled. Finally, this study includes zones for management or conservation of the land, according to the Sustainable Development Goals. 相似文献