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91.
ALEXANDROS A. KARAMANLIDIS PANAYIOTIS DENDRINOS ELENI TOUNTA SPYROS KOTOMATAS 《Coastal management》2013,41(3):293-306
Mediterranean monk seal populations have declined dramatically and survive in subpopulations scattered throughout their original distribution. The National Marine Park of Alonnisos, Northern Sporades is the first marine protected Area dedicated to the protection of the species in the Mediterranean. A Monitoring and Awareness Project has been carried out in the area from 1993 to 2000, the results of which have produced a detailed profile of the human usage pattern of the Park and indicated a significant reduction of illegal activities in the area. The pattern of human usage has enabled the monitoring team to adjust their efforts in the Park over time and provided essential baseline data for future management. The combined monitoring and awareness efforts have contributed significantly to the conservation of the Mediterranean monk seal by successfully protecting pupping sites and reducing human-induced mortality of the species in the area. 相似文献
92.
为解决宿迁市综合客运枢纽与市内快速路网体系(上海快速路)快速衔接问题,对工程概况、技术标准、建设条件进行了分析,根据远景年交通量预测,对总车道边进行了计算,研究确定了城市快速路与综合客运枢纽如何进行快速转换的设计思路,并对总体方案进行了比选,选择出了较优的综合客运枢纽进出站交通方案 相似文献
93.
浅析2013版建设工程工程量清单计价计量规范的变化和特点 总被引:5,自引:0,他引:5
在工程建设中,为全过程控制工程造价,2012年12月25日发布的2013版《建设工程工程量清单计价规范》和各专业工程量计算规范,制定了一序列管理条文,建立起从招投标到竣工结算的工程造价全过程管理机制.为便于新计价、计量规范的贯彻执行,此文将2013版规范与2003版规范和2008版规范进行对比分析,进一步介绍2013版规范修改、完善和增加的内容及特点.推动2013版规范在建设工程中的应用. 相似文献
94.
王勇 《铁路通信信号工程技术》2013,10(1):90-92
探讨在既有线提速改造施工过程中,对S700K转辙设备的调试方法,提高该型转辙设备的调试效率,有效缩短联锁试验时间. 相似文献
95.
聂影 《铁路通信信号工程技术》2013,(6):50-53,60
重载铁路运输是一个复杂的系统工程,对于保证行车安全、提高作业效率和通过能力起关键作用的信号系统提出更高的技术要求.针对开行万吨、2万t组合列车线路设计中遇到的几种特殊站场布局下的信号机设置问题以案例形式进行分析,探讨此类站型信号机设置的影响因素,总结安全、合理的布置原则及运用要求. 相似文献
96.
97.
以贵阳龙洞堡国际机场试验段工程为例对岩溶洼地填筑体变形及稳定性进行数值模拟研究。研究结果表明:强夯对岩溶洼地地基土处理具有较好的效果,能有效降低填筑体的沉降量及边坡位移量;填筑体沉降量随着填筑体厚度减小而减小。 相似文献
98.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(6):705-735
The fault-tolerant control (FTC) of heavy-haul trains is discussed on the basis of the speed regulation proposed in previous works. The fault modes of trains are assumed and the corresponding fault detection and isolation (FDI) are studied. The FDI of sensor faults is based on a geometric approach for residual generators. The FDI of a braking system is based on the observation of the steady-state speed. From the difference of the steady-state speeds between the fault system and the faultless system, one can get fault information. Simulation tests were conducted on the suitability of the FDIs and the redesigned speed regulators. It is shown that the proposed FTC does not explicitly worsen the performance of the speed regulator in the case of a faultless system, while it obviously improves the performance of the speed regulator in the case of a faulty system. 相似文献
99.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):457-464
The quarter car model has been used extensively to study the benefits of active, semi-active and passive suspensions. Despite the evident simplicity of the model, the insights obtained from this model have been found to have counterparts in half- and full-car suspension models. Among the most interesting results of the analysis of the quarter car are the relationships among certain transfer function and invariant points in the frequency response functions. These results are of great interest for the application of linear control techniques to the design of active suspensions and the optimisation of linearised passive suspensions. This paper attempts to show why some of the limitations implied by the model are less absolute than they at first seem. 相似文献
100.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):321-337
In this article, a new drivetrain configuration of a parallel hybrid electric vehicle is considered and a novel model-based control design strategy is given. In particular, the control design covers the speed synchronisation task during a restart of the internal combustion engine. The proposed multivariable synchronisation strategy is based on feedforward and decoupled feedback controllers. The performance and the robustness properties of the closed-loop system are illustrated by nonlinear simulation results. 相似文献