功率IGBT模块的可靠性分析

介绍了功率模块的现状、封装过程、可靠性及其失效规律,论述了研究模块可靠性的标准试验方法如耐力试验和环境试验,讨论了模块的主要失效机制如键合引线失效、表面金属化重建、焊料疲劳和衬底分层等。     

电力安全性对FPSO船举足轻重

随着全球主要油气公司努力通过存储和卸载途径改善海上生产,浮式生产储油船(FPSO)在近年来也越来越受欢迎.由于FPSO深受油气公司欢迎.能生产这类船只的造船厂最近所接到的FPSO订单便因此大增.     

IGBT模块功率损耗的产生机理、计算及模拟

分析了IGBT模块功耗的来源,根据其导通和开关波形讨论了功耗的定义和计算方法;介绍了如何根据模块数据手册估算IGBT及其续流二极管(FWD)的功耗,以及利用PSIM软件模拟模块在应用系统中的功耗;分别利用基本公式和PSIM软件模拟计算和比较了一个逆变电路中IGBT模块的功耗和最高结温。     

The role of geomatics engineering in establishing the marine information system for maritime management

Maritime management encompasses the employment and manipulation of human resources, financial resources, technological resources and natural resources that relate to the sea, maritime navigation, shipping, port development and coastal protection. It contributes to the economic growth, price stability, transportation of cargoes and passengers, and business activities of shipping organizations. The efficient management of resources, operations and activities relies on a modern marine information system (MIS) whose information is provided by geomatics engineers and IT professionals, among others. This paper first introduces the role of the geomatics engineer as geodesist, engineering surveyor, land boundary surveyor, cartographer, hydrographer, photogrammetrist and geographic information system (GIS) engineer since all these fields are related to maritime trade, supply chains and development of ports and airports. It then describes the principal components of a web-based MIS and the important role of geomatics engineers in surveying data. This includes collecting data from electronic nautical charts (ENC) and raster nautical charts (RNC), by applying high resolution light detection and ranging (LIDAR), satellite platform sensors and GIS.     

Benthic foraminifera in the surface sediments of the Beaufort Shelf and slope, Beaufort Sea, Canada: Applications and implications for past sea-ice conditions

This paper presents new data on distribution patterns of modern benthic foraminifera and other microfossils from the Canadian Arctic, specifically the Beaufort Shelf and slope. The material was collected in June to August of 2004 and is the first of its kind in this area to be collected since 1970. We examined the smaller sizes (45–63µm) as well as > 63µm and discovered that many species had been severely underrepresented in previous studies. Deep sea forms, that had been overlooked previously, were common on the shelf; two species (Elphidiella arctica and Ammotium cassis) appeared in preliminary results to be indicators of methane seepage; and it was possible to make determinations of sea-ice coverage using a combination of foraminifera and tintinnids (planktic ciliates). Our data indicated the presence of many of the same species as previous studies from this area, but improved techniques of sample processing greatly increased the number of specimens and species found (particularly the small deep sea arctic species Buliminella hensoni and Bolivina arctica) which provide much more reliable data for paleoceanographic determinations. One of the primary objectives for this work was to provide baseline data to help determine paleo-ice cover; these data cover a broad range of conditions on the Beaufort Shelf that make it possible to achieve this objective as well as improving what it is known about the assemblages on this shelf as compared to other arctic shelf areas, such as the Siberian Shelf).