众多电力公司正在建设信息高速公路

众多电力公司正在建设信息高速公路赫伯特·Ａ·卡凡诺（ＨｅｒｂｅｒｔＡ．Ｃａｖａｎａｕｇｈ）著许荣昌，丛玉译孙佐一校在美国国内各行各业中，公用电力公司最迫切需要企业专用的“实时”通信设施，电力工业在非常大的程度上依靠广泛的内部通信系统来监视、控制、协调...     

影响汽车燃油胶管性能的新因素

对于中等丙烯腈含量的丁腈胶燃油胶管胶料来讲,燃油的渗漏性系随丙烯腈含量增加而提高。添加低分子量的醇作为燃油的增量剂,会对胶料的溶胀和渗漏产生不良影响,当醇的含量为10～20%时,此种不良影响最明显,丁腈胶能耐纯酒精的作用。为改善辛烷值而添加的用量在7%以下的叔丁醇,对丁腈胶并没有不良的影响。对于高芳烃含量的燃油,高丙烯腈含量的丁腈胶以及丁腈胶-聚氯乙烯并用胶具有较低的渗漏性以及较好的耐溶胀性、而且,在醇改性燃油中的耐溶胀性亦有改善.羧基丁腈胶的燃油渗漏性稍低于一般的丁腈胶。以高丙烯腈含量的丁腈胶以及实际可能达到的最高丙烯腈含量的丁腈胶与聚氯乙烯并用以及羧基丁腈胶与聚氯乙烯并用,作为中等丙烯腈含量的丁腈胶的内衬层而制成双层燃油胶管可以成为获得合格的渗漏性和耐低温性能的途径。     

Evaluation of the pollution load discharged at an upstream industry--Egypt--and methods for its reduction

Oil exploration in Egypt is a major contributor to the national Gross Domestic Product (GDP). With 50-65% of the oil resources located in the Gulf of Suez (GoS) region, the impact of such activity upon the region's water environment and its quality cannot be overlooked because of the volume of effluent generated. The objective of this study (September 2000-September 2001) was to assess the impact of a 650,000 barrels/day (bl/d) (100,000 m3/d) effluent arising from a major oil exploration site located south of GoS upon the local water environment. Another objective was to identify the pollutant contents amenable for reduction relative to the new Egyptian regulations. This was achieved by the characterization of the main contributing streams and the identification of the final effluent parameter constraints relative to the type of injection waters used. Subsequent investigations for the reduction of these contents were conducted on site and the results obtained are reviewed herewith.     

TimeLapseAnalyzer: multi-target analysis for live-cell imaging and time-lapse microscopy

The direct observation of cells over time using time-lapse microscopy can provide deep insights into many important biological processes. Reliable analyses of motility, proliferation, invasive potential or mortality of cells are essential to many studies involving live cell imaging and can aid in biomarker discovery and diagnostic decisions. Given the vast amount of image- and time-series data produced by modern microscopes, automated analysis is a key feature to capitalize the potential of time-lapse imaging devices. To provide fast and reproducible analyses of multiple aspects of cell behaviour, we developed TimeLapseAnalyzer. Apart from general purpose image enhancements and segmentation procedures, this extensible, self-contained, modular cross-platform package provides dedicated modalities for fast and reliable analysis of multi-target cell tracking, scratch wound healing analysis, cell counting and tube formation analysis in high throughput screening of live-cell experiments. TimeLapseAnalyzer is freely available (MATLAB, Open Source) at http://www.informatik.uni-ulm.de/ni/mitarbeiter/HKestler/tla.     

Precision of the CAESAR scan-extracted measurements

Three-dimensional (3D) body scanners are increasingly used to derive 1D body dimensions from 3D whole body scans for instance, as input for clothing grading systems to make made-to-measure clothing or for width and depth dimensions of a seated workstation. In this study, the precision of the scanner-derived 1D dimensions from the CAESAR survey, a multinational anthropometric survey, was investigated. Two combinations of scanning teams with 3D whole body scanners were compared, one called the US Team and the other the Dutch Team. Twenty subjects were measured three times by one scanner and one team, and three times by the other combination. The subjects were marked prior to scanning using small dots, and the linear distances between the dots were calculated after processing the scans. The mean absolute difference (MAD) of the repetitions was calculated and this was compared to reported acceptable errors in manual measurements from the US Army's ANSUR survey when similar measurements were available. In addition, the coefficient of variation (CV) was calculated for all measurements. The results indicate that the CAESAR scan-extracted measurements are highly reproducible; for most measures the MAD is less than 5mm. In addition, more than 93% of the MAD values for CAESAR are significantly smaller than the ANSUR survey acceptable errors. Therefore, it is concluded that the type of scan-extracted measures used in CAESAR are as good as or better than comparable manual measurements. Scan-extracted measurements that do not use markers or are not straight-line distances are not represented here and additional studies would be needed to verify their precision.     

Bilateral control of master-slave manipulators with constant time delay

This paper presents a novel teleoperation controller for a nonlinear master-slave robotic system with constant time delay in communication channel. The proposed controller enables the teleoperation system to compensate human and environmental disturbances, while achieving master and slave position coordination in both free motion and contact situation. The current work basically extends the passivity based architecture upon the earlier work of Lee and Spong (2006) [14] to improve position tracking and consequently transparency in the face of disturbances and environmental contacts. The proposed controller employs a PID controller in each side to overcome some limitations of a PD controller and guarantee an improved performance. Moreover, by using Fourier transform and Parseval's identity in the frequency domain, we demonstrate that this new PID controller preserves the passivity of the system. Simulation and semi-experimental results show that the PID controller tracking performance is superior to that of the PD controller tracking performance in slave/environmental contacts.