Changes in the shelf macrobenthic community over large temporal and spatial scales in the Bohai Sea, China

Over the past 20 years, the Bohai Sea has been subjected to a considerable human impact through over-fishing and pollution. Together with the influence of the Yellow River cut-off, the ecosystem experienced a dramatic change. In order to integrate available information to detect any change in macrobenthic community structure and diversity over space and time, data collected during the 1980s and the 1990s from 3 regions of the Bohai Sea (Laizhou Bay, 16 stations, 37–38°N, 119–120.5°E; central Bohai Sea, 25 stations, 38–39°N, 119–121°E; eastern Bohai Bay, 12 stations, 38–39°N, 118.5–119°E) were reanalyzed in a comparative way by means of a variety of statistical techniques. A considerable change in community structure between the 1980s and the 1990s and over the geographical regions at both the species and family level were revealed. After 10 years, there was a considerable increase in abundance of small polychaetes, bivalves and crustaceans but decreased number of echinoderms. Once abundant in Laizhou Bay in the 1980s, a large echinoderm Echinocardium cordatum and a small mussel Musculista senhousia almost disappeared from the surveying area in the 1990s. Coupled with the increased abundance was the increased species richness in general whereas evenness was getting lower in central Bohai Sea and Bohai Bay but increased in Laizhou Bay. K-dominance plot showed the same trend as evenness J′. After 10 years, the macrobenthic diversity in the Bohai Sea as a whole was slightly reduced and a diversity ranking of central Bohai Sea > Laizhou Bay > eastern Bohai Bay over space was also suggested. Sediment granulometry and organic content were the two major agents behind the observed changes.     

802.1X在MA5200E/F上的实现和应用

MA5200E／F的组网方式可充分发挥运营商的个性，极大地满足不同场合、不同客户端情况下的灵活应用。     

皇冠轿车A340E自动变速器的故障诊断与维修

介绍皇冠轿车A340E自动变速器结构及故障的诊断、维修方法。     

国际航运电子市场分析

从介绍近年来电子商务革命对航运业发展的深刻影响入手，阐述了国际航运电子市场的优点、发展演化。根据市场规模和交易频率、市场套利能力和市场信息不均衡性等3个重要因素，分析了国际航运电子市场的定价形态，并进一步分析了相应的定价政策。从而为航运交易的各方进入国际航运电子市场，实现其盈利目标提供了有益的参考。     

海洋钻井平台桩腿齿条板与半圆板焊接工艺试验

针对400ft钻井平台桩腿齿条板与半圆板焊接全熔透的新要求,笔者通过试验和不同施焊方法相结合的方式分析了组对间隙和清根与否等因素对Q690E试板接头根部熔深的影响。结果表明,无论采用何种焊接方法,反面清根后施焊,接头熔合状况均良好,且采用实芯焊丝比药芯焊丝接头熔深大。正面气保焊打底,反面不清根采用气保焊施焊,接头熔合不良;而反面采用埋弧焊施焊,接头可实现熔透,但工艺还有待优化,以避免结晶裂纹的产生。     

导读台9线苏花公路改善计划

正推动中之台9苏花公路改善系建构于强化路线抗灾维生性及运输安全服务性,该计划目标系为改善苏花公路的安全性与可靠度,范围系台9线苏花公路山区路段,北起苏澳附近台2线与台9线路口(里程104K+726),往南经东澳、南澳、鼓音、汉本、和平、和中、和仁、清水至崇德(立雾溪畔止,台9线里程约182 km),全长约77 km路段中,总计改善长度约38.4 km,其中,隧道段就占23.4 km。其计划经费约492亿元,含用地、规划、工程及物价指数调整,用地需求除路线构造使用,并考量路线安全维护设置地磅管制站及交控系统设施需求。2010年底完成环评后,2011年初动工,预定2017年完成,全面开放则需俟其机电系统、交通控制系统及防灾系统等工程之整合与测试完成后方可通车。     

Real time assimilation of HF radar currents into a coastal ocean model

A real time assimilation and forecasting system for coastal currents is presented. The purpose of the system is to deliver current analyses and forecasts on based on assimilation of high-frequency radar surface current measurements. The local Vessel Traffic Service monitoring the ship traffic to two oil terminals on the coast of Norway received the analyses and forecasts in real time.A new assimilation method based on optimal interpolation is presented where spatial covariances derived from an ocean model are used instead of simplified mathematical formulations. An array of high frequency radar antennae provides the current measurements. A suite of nested ocean models comprises the model system. The observing system is found to yield good analyses and short range forecasts that are significantly improved compared to a model twin without assimilation. The system is fast, analysis and 6-h forecasts are ready at the Vessel Traffic Service 45 min after acquisition of radar measurements.     

急性散发性戊型肝炎患者血清抗体的动态检测

动态检测了34例1993年6月～1994年5月在我校附属医院住院确诊的急性散发性戊型肝炎患者血清IgM、IgG抗-HEV变化。15例患者IgM和IgG同时阳性。16例平均随访观察303d（6个月～15个月）。结果：IgM、IgG抗-HEV阳性最早出现在黄症后第3天；黄疸后10d阳性率分别达86．7％和100％。两抗体在病初1周时滴度最高，以后缓慢下降，IgM下降较快，病程2月时所检患者均降至不能检出水平；IgG抗体除1例外均在1年左右阴转。ALT在抗体出现后很快下降，6周降至近正常水平。IgM抗-HEV检出率仅44．1％，故不宜仅以此作为急性戊型肝炎诊断标准，应结合IgGJ立体动态变化，综合判断。     

中控系统和现场控制盘之间的信号分析与设计

本文主要分析了中控系统和现场控制盘之间的几组信号,对于现在所使用的设计方法进行了优化,使它们更能满足现场生产的需要,同时也可以提高设计水平,开拓设计思路.     

北外环输气站场SIS系统技术改造

北外环集输管道工程是川渝地区管网建设的重点工程,因此有必要对站场SIS系统的设计情况进行研究,剖析存在的影响安全运行的问题。采用设备硬件改造与系统软件改造相结合的方式,从设计原则、改造方式、ESD逻辑动作、破管检测联锁等多方面详细阐述了技术改造措施,通过现场测试与验证,实现了SIS系统的故障安全性与系统联锁控制,也为类似站场SIS系统改造提供了技术支撑。