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81.
Since 1992, the National Space Development Agency of Japan (NASDA) and the Economic and Social Commission for Asia and the Pacific (ESCAP) have been co-organising the Regional Remote Sensing Seminar on Tropical Ecosystem Management (Program Chairman: Prof. Shunji Murai) every year in some country in Asia. In these seminars, the members of the ISPRS Working Group VI/2 ‘Computer Assisted Teaching’ have been performing a PC-based hands-on-training on remote sensing and GIS for beginners. The main objective of the training was to transfer not only knowledge but also the technology of remote sensing and GIS to the beginners. The software and CD-ROM data set provided at the training were well designed not only for training but also for practical data analysis. This paper presents an outline of the training and discusses the optimisation of PC-based training for remote sensing and GIS.  相似文献   
82.
基于椭圆型缓坡方程和消息传递接口机制,提出了缓坡地形上非线性波浪变形的一种并行数值模拟方法,并在微机群集并行系统上进行了数值实现.对一种典型缓坡地形上的非线性波浪传播变形进行了数值模拟,数值结果与实验数据的比较表明,在椭圆型缓坡方程中应用非线性波色散关系可有效考虑波浪的非线性效应,同时从获得的并行效率和并行加速比来看,并行数值方法可有效提高数值模拟效率.  相似文献   
83.
基于PC/104平台的嵌入式Linux技术在海洋自动观测系统中具有广泛的应用前景,Linux内核启动过程的分析是嵌人式Linux系统研究的基础。文章就Linux内核在PC/104单片机上的启动过程进行分析与研究。  相似文献   
84.
We present a comprehensive near-infrared study of two molecular bow shocks in two protostellar outflows, HH 99 in R Coronae Australis and VLA 1623A (HH 313) in Rho Ophiuchi. New, high-resolution, narrow-band images reveal the well-defined bow shock morphologies of both sources. These are compared with two-dimensional MHD modelling of molecular bows from which we infer flow inclination angles, shock speeds and the magnetic field in the pre-shock gas in each system. With combined echelle spectroscopy and low-resolution K -band spectra we further examine the kinematics and excitation of each source. Bow shock models are used to interpret excitation (CDR) diagrams and estimate the extinction and, in the case of VLA 1623, the ortho–para ratio associated with the observed H2 population. For the first time, morphology, excitation and kinematics are fitted with a single bow shock model.
Specifically, we find that HH 99 is best fitted by a C-type bow shock model (although a J-type cap is probably responsible for the [Fe  ii ] emission). The bow is flowing away from the observer (at an angle to the line of sight of ∼45°) at a speed of roughly 100 km s−1. VLA 1623A is interpreted in terms of a C-type bow moving towards the observer (at an angle to the line of sight of ∼75°) at a speed of ∼80 km s−1. The magnetic field associated with HH 99 is thought to be orientated parallel to the flow axis; in VLA 1623A the field is probably oblique to the flow axis, since this source is clearly asymmetric in our H2 images.  相似文献   
85.
网络化地电阻率仪的研究   总被引:1,自引:1,他引:0       下载免费PDF全文
王兰炜  赵家骝 《地震学报》2008,30(5):484-490
地震观测仪器技术的发展与计算机技术的发展密切相关. 近年来, 集PC机功能于一体的嵌入式PC104模块得到了广泛的应用, 给设计人员提供了一种全新、 灵活的硬件设计环境. 本文介绍了采用低成本、高可靠性的嵌入式PC104模块实现地电阻率仪网络化的方法和网络化仪器主要功能.   相似文献   
86.
Elemental abundances of 28 And (A7 III) and 99 Her (F7 V), which have modest rotational velocities, are derived in a manner consistent with previous studies in this series of papers. The values for 28 And, a δ Scuti variable, show that it is slightly metal-poor, but not a classical Am star. 99 Her, which is somewhat more metal-poor, has a rather small microturbulence for its spectral type.  相似文献   
87.
Currently, the reduction of weight in automotive is a very important topic to reduce the air pollution. In this context, the purpose of the present paper is to analyze a real case study through a comparison of the environmental impacts between a conventional steel bumper and a polyester prototype. In the first part of this work, a door-to-door life-cycle assessment methodology was used throughout the study of the component manufacturing phase. The SimaPro 7.1 software is used to evaluate the impacts of both bumpers on the environment and health. The second part is devoted to dust analysis from the polyester workshop. The obtained results have allowed us to show the company that its choice of steel substitution by the polyester is advantageous for certain impacts including the impact of climate change, but unfortunately there may be, given the working conditions of the polyester workshop, a transfer of impact, since we will end up with a risk of health (irritations, cancers) for the workers. LCA has proven to be a very useful tool for validating a redesigned automotive component from an environmental point of view; from this case study, several recommendations were made for the company to design environmentally friendly components, and ecodesign should be introduced into the company’s procedures.  相似文献   
88.
可扩展的并行地理图像处理系统 (Par GIP)是基于多操作系统平台的机群并行图像处理系统 ,它采取Client- Server结构 ,采用插件技术和算法化的处理操作 ,具有良好的发展前景.  相似文献   
89.
预制空心板受火后力学性能的试验研究   总被引:1,自引:0,他引:1  
为比较不同受火时间后预制空心板剩余承载力、跨中挠度和破坏形态的异同,进行了6块预制空心板受火后力学性能的对比试验研究,其中3块为未受火的对比试件,另3块为板底分别受火23、38、53min的试件。受火试验结果表明,各试件在升温过程中的跨中挠度随受火时间增加而显著增加,熄火自然冷却后,跨中挠度大部分可恢复。加载试验结果表明,对比试件和受火试件的最终破坏模式均为弯曲破坏;随着受火时间延长,试件开裂荷载和破坏荷载均有所降低,且破坏荷载与受火时间大致呈线性关系;受火试件初始弯曲刚度较对比试件明显降低,相同荷载作用下,受火试件受拉边缘拉应变和受压边缘压应变,均明显大于对比试件。  相似文献   
90.
杨玉忠 《东北测绘》2012,(2):185-186,190
主要介绍PC-E 500计算机在现阶段水准测量记录中再利用的必要性 可行性及实际应用。  相似文献   
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