A new method of transmission network flexible planning using the connection number

Because connection number can express and process synthetic uncertainties caused by various uncertainties in the transmission network planning, a connection number model (CNM) was presented to compare the values of connection number logically. This paper proposed a novel model for transmission network flexible planning with uncertainty. In the proposed planning model both certainty and uncertainty information were included, and the cost-benefit analysis method was used to evaluate the candidate schemes in the objective function. Its good adaptability and flexibility were illustrated through two examples.     

A method for determining surface free energy of bamboo fiber materials by applying Fowkes theory and using computer aided machine vision based measurement technique

The purpose of this study is to develop a standard methodology for measuring the surface free energy (SFE), and its component parts of bamboo fiber materials. The current methods was reviewed to determine the surface tension of natural fibers and the disadvantages of techniques used were discussed. Although numerous techniques have been employed to characterize surface tension of natural fibers, it seems that the credibility of results obtained may often be dubious. In this paper, critical surface tension estimates were obtained from computer aided machine vision based measurement. Data were then analyzed by the least squares method to estimate the components of SFE. SFE was estimated by least squares analysis and also by Schultz?? method. By using the Fowkes method the polar and disperse fractions of the surface free energy of bamboo fiber materials can be obtained. Strictly speaking, this method is based on a combination of the knowledge of Fowkes theory. SFE is desirable when adhesion is required, and it avoids some of the limitations of existing studies which has been proposed. The calculation steps described in this research are only intended to explain the methods. The results show that the method that only determines SFE as a single parameter may be unable to differentiate adequately between bamboo fiber materials, but it is feasible and very efficient. In order to obtain the maximum performance from the computer aided machine vision based measurement instruments, this measurement should be recommended and kept available for reference.     

基于事故空间分布交通事故多发地点鉴定新方法

引言 道路交通事故多发点又称黑点(Black Spot),是指道路上交通事故显著突出的路段或交叉口.如果道路交通事故的发生是完全随机的,那么道路交通事故在不同路段上的分布应该是均匀的,而一些事故异常集中的路段则反映了该处可能存在着影响交通安全的不利因素.     

改善沥青混合料高温稳定性的方法

从试验、强度形成机理、施工角度进行分析,评价这些手段对改善沥青混合料高温稳定性的有效性。     

A new model for simulation of cold roll-forming of tubes by using spline finite strip method

A new model,called object model,for the simulation of cold roll-forming of tubes is presented.The model inherits the advantages of old models and is the embodiment of forming process that the strip is rolled step by step from feed rollers to last rolling pass.The elastic-plastic large deformation spline finite strip method based on updated Lagrangian method has been developed by improving the stiffness and transition matrix.Combined theory formulas and new analytical model,the forming process of a tube has ...     

基于路面车辙性能的长大纵坡划分方法研究

首先就长大纵坡路段沥青路面损坏进行调查,然后进行车速变化和水平荷载下长大纵坡路段的路面性能分析,最后就长大纵坡划分标准进行了研究。综上研究,提出根据行车车速作为长大纵坡的划分指标,优化连续纵坡行车车速预估模型,并提出长大纵坡路段的划分标准。     

新型多功能路面的铺装方法

对近年来国内外发展起来的几种多功能路面的铺装方法和特点进行了介绍,对多功能路面的作用机理,设计和施工方法,优缺点和使用前景等进行了综合分析和探讨。     

A novel method to calculate the thrust of linear induction motor based on instantaneous current value

Because of the end effect,a linear induction motor (LIM) runs in an asymmetrical state even though the winding of each phase is symmetric.Based on the basic principle of the LIM,a new approach was prop...     

基于克隆选择算法的模糊规则提取方法

结合人工免疫系统的克隆选择原理,采用克隆算法进行优化,提取通过多精度模糊分割产生的大量模糊if-then规则中的优质分类规则,建立了模糊分类所需要的有效规则集来实现分类的目的.由该方法所提取的模糊规则集具有分类正确率高、规则数目较少及识别时间短的特点.     

一种基于数字水印的二维条码防伪的方法

针对现有PDF417条码的数字水印嵌入和检测算法比较复杂、水印的嵌入强度不好控制以及对条码打印机和扫描仪的精度要求比较高等问题,提出了一种在PDF417条码的合适边缘嵌入盲水印信息的方法,将二维条码和数字水印技术相结合以提高PDF417二维条码的安全性和保密性.     

基于改进TOPSIS法的城市公交发展水平评价方法

从公共交通的运营能力、服务能力及发展能力等3方面建立了评价指标体系,运用结构熵权法,确定了各个指标的权重。将评价指标分成成本型指标、效益型指标及区间型指标,对TOPSIS法进行了改进,并建立了城市公共交通发展水平的评价模型。进行了实例分析,分别选取两个城市,进行了公共交通发展水平的评价。分析结果表明：该评价方法合理可行。     

基于神经网络的交通流检测设备布设研究

针对目前交通流检测设备布设中出现的一些问题,借助均匀设计方法,结合神经网络处理观测交通流数据,在设置数量有限制条件下,开展布设方案优化设计研究。本文的方案设计力图在人力物力投入最小的前提下,通过典型路段、交叉口等交通基础设施的组合,可以更多的获取交通流参数信息,全面、准确的反映城市交通流分布情况。选用了67的均匀设计表作为方案设计基础表,经过拟水平处理后设计优化方案,运用BP神经网络构建交通量推断模型,判定设计方案的优劣,进行了实地交通流检测设备优化布设研究。通过研究可知,采取优选布设方案采集的交通量对检测路段交通量进行预测,相对偏差可以达到0.006。     

A comprehensive evaluation method for kinematic accuracy of space manipulator based on analytic hierarchy process

The kinematic accuracy of space manipulator determines whether the spacecraft performs normally or not. Problems pertaining to structural deformation have received increased attention in recent times. In the space manipulator systems, flexible arms and joints can induce drastic dynamic instabilities. In applications such as the space station, kinematic error due to structural deformation can jointly affect the performance characteristics. And it is crucial for accuracy control of space manipulator to establish a precision index. Here we analyze the dynamics characteristic of flexible space manipulator considering the hysteresis of harmonic reducer based on method of nonconstraint boundary modal. For the sake of describing the output accuracy, we integrate the method of analytic hierarchy process(AHP) to establish a comprehensive evaluation index. A numerical simulation is performed to analyze the nonlinear dynamic characteristics of space manipulator with harmonic reducer. With the analysis of accuracy assessment, the relation among the hysteresis angle, rigidity and output accuracy is revealed. Considering the elastic modulus of flexible space manipulator and the hysteresis angle of harmonic reducer, we conduct an evaluation of output characteristics of flexible space manipulator with the proposed comprehensive evaluation index. The accuracy evaluation of output characteristics based on the proposed comprehensive evaluation index is implemented in the initial stage of space manipulator’s design, which can not only solve the problems existing in the design but also save cost savings for ground tests. The results can be used in designing and optimizing future space manipulators, which may provide valuable references for design and thermal control of the space manipulator.     

A new algorithm to automatically extract the drainage networks and catchments based on triangulation irregular network digital elevation model

A new algorithm to automatically extract drainage networks and catchments based on triangula- tion irregular networks （TINs） digital elevation model （DEM） was developed. The flow direction in this approach is determined by computing the spatial gradient of triangle and triangle edges. Outflow edge was defined by comparing the contribution area that is separated by the steepest descent of the triangle. Local channels were then tracked to build drainage networks. Both triangle edges and facets were considered to con- struct flow path. The algorithm has been tested in the site for Hawaiian Island of Kaho＇olawe, and the results were compared with those calculated by ARCGIS as well as terrain map. The reported algorithm has been proved to be a reliable approach with high efficiency to generate well-connected and coherent drainage networks.     

蜡封法测定压实沥青混合料试件

蜡封法是利用物理学中的浮力原理，利用试件排开水的体积来代替试件的体积。具体的测量方法是：用和试件毛体积完全体积相当的水的质量除以水的比重。以此要得到个准确的毛体积密度，问题的关键是水的质量必须是和试件毛体积相当的水的质量。当沥青混合料的空隙率很大，即混合料的开口空隙较多时沥青混合料的饱和面干状态就很难达到。在这种情况下，我们采用蜡封法，     

新分期带来的胆囊癌手术范围合理性的争议

根治性手术切除是治疗胆囊癌的最重要手段,TNM癌症分期是制定手术方案的重要依据,但目前不同分期患者的手术方式选择及切除范围尚无统一标准.本文以美国癌症联合委员会(AJCC)第8版癌症分期系统为基础,结合国内外研究进展及本中心临床治疗经验,探讨不同分期胆囊癌患者手术治疗的现状与争议.     

利用数字地面模型建立公路横断面模型的新方法

笔者利用空间解析几何原理 ,提出了新型、有效的在数字地面模型中公路横断面模型的建立方法 .该方法能够使公路模型和数字地面模型更完整的结合     

A novel de-noising method based on discrete cosine transform and its application in the fault feature extraction of hydraulic pump

Aiming at the existing problems of discrete cosine transform (DCT) de-noising method, we introduce the idea of wavelet neighboring coefficients (WNC) de-noising method, and propose the cosine neighboring coefficients (CNC) de-noising method. Based on DCT, a novel method for the fault feature extraction of hydraulic pump is analyzed. The vibration signal of pump is de-noised with CNC de-noising method, and the fault feature is extracted by performing Hilbert-Huang transform (HHT) to the output signal. The analysis results of the simulation signal and the actual one demonstrate that the proposed CNC de-noising method and the fault feature extraction method have more superior ability than the traditional ones.     

浅谈施工企业如何应对低价中标

本文从施工企业的角度出发,针对目前深圳市建设工程招投标市场中出现的采用低价中标的评标方法,从施工企业定额、不平衡报价、责任分解和施工企业成本管理方面详细阐述了施工企业应对低价中标的四种措施,实践证明,这些措施是行之有效的.     

浅谈施工企业如何应对低价中标

本文从施工企业的角度出发,针对目前深圳市建设工程招投标市场中出现的采用低价中标的评标方法,从施工企业定额、不平衡报价、责任分解和施工企业成本管理方面详细阐述了施工企业应对低价中标的四种措施,实践证明,这些措施是行之有效的.