基于GIS的云龙示范区土地利用转移分析

土地利用变化的空间特征和变化规律分析是区域规划的重要依据。在RS/GIS技术支持下,以云龙示范区2005和2010年2期遥感数据为主要数据源,结合相关软件进行图像及数据的处理;运用土地利用转移矩阵和土地利用动态度、土地变化强度等指标对研究区土地利用的空间变化进行了研究。结果表明:5年间云龙示范区土地利用变化总量为48.61 hm2,增长3.26%;土地利用动态度差异明显,林地和水域面积维持稳定,但建设用地和耕地变化较大,土地利用变化强度为0.65。该结果可为区域土地利用动态监测提供数据支撑,也可为云龙示范区规划及建设提供参考依据。     

3-D Finite-Element Numerical Simulation of Centrifugal Induction Electrosalg Casting Solidification Process

A 3-D finite-element numerical simulation model of temperature field for CIESC casting solidification process was developed with the aid of ANSYS software and a series ofcorresponding experiments were made. The results showed that the good agreement was obtained between the numerical simulation and the experiments. Based on the numerical simulation results, the characteristics of tem- perature distribution in the castings during CIESC solidification process were analyzed and summarized. According to the G/R1/2 method and numerical simulation results, there is no any shrinkage defect in the CIESE casting and structure of casting is fine and compact.     

CAPP 的研究和发展

目的　为了正确地认识和理解 CAPP.方法　论述了 CAPP的研究现状 ,并就与 CAPP的研究相关的问题进行了初步的分析 .结果　 CAPP的作用是巨大的 ,并且与机械制造业的其他领域紧密联系 ,但尚存在一些问题 .结论　作为对 CAPP的综述 ,为把握 CAPP的发展和研究方向提供了指南     

国外交通运输项目费用效益分析的理论与实践

一、引言 费用效益分析法(CBA)在交通运输业最早进入常规应用,并成为其决策的组成部分.费用效益分析在交通领域的应用已经有了相当长的历史,现在它已经发展成为公路规划、公共交通规划等中最常见的评价方法.费用效益分析在交通领域得到广泛的应用的原因是多方面的.一方面,大量相对接近的规划项目需要进行排队,而费用效益分析法作为一种规范的评价体系,比主观判断更具有说服力;另一方面,交通项目的主要效益--运营费用节约效益和时间节约效益比较易于计量,与其他较敏感的项目规划(如健康项目等)相比,比较容易货币化.不管是什么原因,交通项目评价的长久历史足以证明了这种方法的价值所在.     

对一类基于离散对数的代理盲签名体制的伪造攻击

对Tan等人的代理盲签名方案，提出了一种伪造攻击，利用该伪造攻击，不诚实的原始签名人可以成功伪造代理签名密钥，从而能够假冒合法代理签名人生成验证有效的代理盲签名，威胁到代理签名人的合法权益．进而针对所提出的伪造攻击，对Tan等人的代理盲签名方案进行改进，克服了代理委托过程中造成代理签名密钥可伪造的因素，即r^-的选择性构造，设计了一个新的代理盲签名方案．     

Radiometric cross-calibration of the CBERS-02 CCD camera with the TERRA MODIS

For the application of the CCD camera, the most important payload on CBERS-02, the key is to provide long-term stable radiometric calibration coefficients. Although the vicarious calibration had been proved successful, it had its limitations such as test site requirement and unsuitable for historical data. Cross-calibration is one of the alternative methods, but it needs synchro surface spectrum to achieve spectral band matching factors. Our effort is to probe the influences on these factors. Simulations with a lot of surface spectrum showed that the factors changed with the viewing geometry, atmospheric condition and surface targets. However, simulating with the same viewing geometry and atmospheric condition, the spectral band matching factors of the same or similar surface targets, spectrum acquired from different dates and different places would like to be consistent to each other within 1%–5%. Thus, the synchro measurement data can be substituted by the same or similar target from other source. Based on this method, using the MODIS as the reference, the cross-calibration was performed for CCD camera. The research demonstrated that the traditional method with single calibration site was inappropriate for CCD camera, since the offsets for its four spectral bands were not zeros. With four calibration sites, these offsets were obtained. And the camera was detected to degrade with dates based on four times of cross-calibrations.     

针织物热传递性能研究

本文主要讨论了针织物的热传递性能。在分析针织物热传递机理的基础上,又进一步通过实验得到了针织物原料、线圈长度、厚度、透气性与织物热阻值ｃｌｏ的关系,同时也对环境条件——风速的影响进行了讨论。理论分析与实验结果表明：针织线圈所包围的空气量是影响针织物热阻的主要因素,而纺织材料本身的影响要小得多。     

5—单硝酸异山梨醇酯的合成研究（Ⅰ）

本文由山梨醇经脱水、酰化、硝化及皂化合成了５单硝酸异山梨醇酯．脱水收率６５％；酰化、硝化及皂化总收率３０％．并对工艺条件进行了初步优化．