浅析GPS高程测量在水利工程中的应用

简要介绍了GPS高程测量的原理,结合其在水利工程中的应用实例,对GPS高程测量技术进行了探讨。     

Efficient and power-awareness query over sensor networks

Sensor networks consisted of low-cost, low-power, multifunctional miniature sensor devices have played an important role in our daily life. Light and humidity monitoring, seismic and animal activity detection, environment and habitat monitoring are the most common applications. However, due to the limited power supply, ordinary query methods and algorithms can not be applied on sensor networks. Queries over sensor networks should be power-aware to guarantee the maximum power savings. The minimal power consumption by avoiding the expensive communication of the redundant sensor nodes is concentrated on. A lot of work have been done to reduce the participated nodes, but none of them have considered the overlapping minimum bounded rectangle (MBR) of sensors which make them impossible to reach the optimization solution. The proposed OMSI-tree and OMR algorithm can efficiently solve this problem by executing a given query only on the sensors involved. Experiments show that there is an obvious improvement compared with TinyDB and other spatial index, adopting the proposed schema and algorithm.     

Conflict Pattern Analysis: Preparing the Ground for Participation in Policy Implementation

The participation of non-state actors in implementation processes is often understood as a means to increase compliance efficiency. But the implementation of spatial policies frequently focuses on pre-established goals, processes and instruments and thus renders difficult open discourse and shared decision-making. This paper introduces conflict pattern analysis (CPA) as a tool that supports the analysis of the actual actor constellation in order to define efficient approaches that avoid common problems of participatory processes. CPA is a semi-formalised method that helps to identify key-actors, their relations and interaction amongst each other as well as their core beliefs, interests and resources. It aggregates this information to interaction patterns that can be compared, classified and linked to different participatory methods on a theoretically informed basis. Particularly on the local and regional level, this could be the first step for successful (participatory) implementation strategies.     

《液压传动与控制》教学改革探索

针对机械类大学生学习液压传动的特点和要求,从教学手段和教学内容等方面论述了如何对《液压传动与控制》课程进行教学改革。     

小型汽车制动能量再生系统参数建模及仿真

针对一种型号的小型汽车制动能量再生系统, 进行了制动减速和起步加速过程相关参数建模,利用Matlab软件对此车制动能量回收及能量释放过程的车辆速度、加速度、液压蓄能器气囊压力、体积进行了仿真.通过对仿真结果的分析,得出的结论为:在制动减速过程,所选择的蓄能器能满足制动减速过程吸收完制动能量的要求;在起步加速过程,该蓄能器利用所储存的能量能够使该小型汽车起步加速到一定车速,从而满足车辆倒拖发动机,使发动机高速自行起动的要求.     

基于复杂网络的指挥控制信息协同模型研究

网络化作战的时代特征迫切需要新的仿真模型和评价方法,以预测信息优势对作战效果的影响。在描述网络化指挥控制活动特点的基础之上,从复杂网络角度出发建立起指挥控制信息协同模型,并就不同规则演化下的网络特征变化进行了定量分析,从而为评估信息协同对作战效果的影响提供了新的研究思路和方法。     

高精度液压试验台的油温自动控制研究

从降低液压试验台温控系统的成本而又保证温控精度出发，分析影响温控精度提高的主要因素，提出了采用串级双闭环负反馈的温控方案，并应用辨识技术获得了被控对象的较精确的数学模型，通过两级校正，使温控精度达到了５０±１℃。     

南屯矿63_上10面综采放顶煤开采覆岩移动变形破坏特征研究

本文根据使用新技术──双回路注（放）水系统在６３上１０工作面综采放顶煤开采覆岩破坏的探测结果，结合其它采矿方法的实测结果，应用断裂力学理论，研究了放顶煤开采覆岩移动变形破坏特征，为矿井安全生产提供了依据。     

淬火工艺对铬结构钢显微组织和机械性能的影响

本文研究了淬火工艺对低和中碳铬钢的显微组织,冲击韧性和断裂机制的影响,得出了无论是低碳,还是中、高碳钢,当奥氏体长大倾向稍大时,采取提高加热温度进行淬火的工艺均为不可取的结论。     

Samples Selection for Artificial Neural Network Training in Preliminary Structural Design

An artificial neural network (ANN) is applied in the preliminary structural design of reticulated shells. Major efforts are made to enhance the generalization ability of networks through well-selected training samples. Number-theoretic methods (NTMs) are adopted to generate samples with low discrepancy, i.e.uniformly scattered in the domain, where discrepancy is a quantitative measurement of the uniformity. The discrepancy of the NTM-based sample set is 1/6-1/7 that of samples with equal spacing. In a case study,networks trained by NTM-based samples are compared with those trained by equal-spaced samples in generalizing performance. The results show that both the computational precision and stability of the former ANNs are more satisfactory than those of the latter. It is concluded that the flexibility of ANNs in generalizing can be effectively increased by use of uniformly distributed training samples rather than simply piling data.More reliable uniformity should be obtained, however, through NTMs instead of equal-spaced samples.