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随着我国医疗科技的发展速度不断加快,用于临床的医疗设备技术也日趋成熟。在制氧领域,医用制氧机的应用范围逐步扩大,为了使医用制氧机能够始终处于稳定可靠的运行状态,需要充分分析制氧机系统的工作原理,针对制氧机中的空压机系统故障制定切实可行的维修方案。本文就以上背景,提出医用制氧机基本概念,分析医用制氧机空压机系统的工作原理;针对医用制氧机空压机中的故障以及供氧机系统故障提出维修对策,以期达到在临床中安全、高效、便捷地使用医用制氧机的最终目标。 相似文献
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延长ZD/3.5—15/12型空压机活塞环使用寿命的方法 总被引:2,自引:0,他引:2
分析了ZD/3.5-15/12型空压机活塞环磨损严重的情况,并提出了延长其使用寿命的几个改进措施,如更新空气滤清器或增加一道过滤器,提高设备冷却器的冷却效果,降低进入气缸的空气温度等。 相似文献
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通过维修实例,阐述对于电控发动机的故障,汽车维修人员应根据两次调取的故障代码和路试结果作为故障诊断的重要依据,不可仅靠调出的故障代码来决定电控系统的故障所在,因为有些电控元件的故障信息不能通过电控参数反映给ECU. 相似文献
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103JAT合成气压缩机高压透平已运行30多年,蒸汽消耗量较大,装置运行成本高,仅更新改造蒸汽透平转子及相关的部件就能达到降低能耗的目的。103JAT合成气压缩机高压透平改造的同时,改善了合成气压缩机辅助透平103JBT的工作状况,103JBT的蒸汽消耗和故障率减少。103JAT改造减少了蒸汽的消耗量,由此给装置带来的经济效益是可观的。 相似文献
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Current air traffic control systems are mainly conceived to ensure the safety of flights by means of tactical interventions, because of the difficulty of accurately foreseeing the traffic evolution. In fact, in real traffic conditions, planes are often penalized since sometimes safety standards are redundant. Today, this management philosophy is no longer valid because of congestion phenomena which often occur in the most important terminal areas. Therefore, as to future control systems it is necessary to introduce not only more automated procedures to keep adequate safety levels, but also planning functions in order to increase the system capacity and to improve system efficiency. In recent years several studies have been carried out, new control concepts have been introduced and some optimization models and algorithms developed to improve air traffic management. In this paper a survey of our early works in this field is reported and a multilevel model of air traffic management is proposed and discussed. The functions corresponding to the on-line control, that is flow control, strategic control of flights and aircraft sequencing in a terminal area, are examined and the optimization models and solution algorithms are illustrated. Finally, relevant problems coped by recent research are mentioned and new trends are indicated. 相似文献
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《Transportation Research Part D: Transport and Environment》2007,12(3):158-166
Japan’s Air Pollution Control Law signed in 1968 prescribes the maximum permissible limits of motor vehicle exhausts as well as establishing mechanisms for monitoring air pollution In this paper, the grey relational grade of air pollutants from ambient air pollution and roadside air pollution monitoring stations is used to look at the relationship between air pollution and transportation. The results indicated that the ambient and roadside air quality increased by rose from 1975 to 2004 but less fast than the growth in traffic. Some of this may be attributable to the legislation but there have also been other measures since 1968 that have also contributed. 相似文献
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Abstract The history of urban traffic control (UTC) throughout the past century has been a continued race to keep pace with ever more complex policy objectives and consistently increasing vehicle demand. Many benefits can be observed from an efficient UTC system, such as reduced congestion, increased economic efficiency and improved road safety and air quality. There have been significant advances in vehicle detection and communication technologies which have enabled a series of step changes in the capabilities of UTC systems, from early (fixed time) signal plans to modern integrated systems. A variety of UTC systems have been implemented throughout the world, each with individual strengths and weaknesses; this paper seeks to compare the leading commercial systems (and some less well known systems) to highlight the key characteristics and differences before assessing whether the current UTC systems are capable of meeting modern transport policy obligations and desires. This paper then moves on to consider current and future transport policy and the technological landscape in which UTC will need to operate over the coming decades, where technological advancements are expected to move UTC from an era of limited data availability to an era of data abundance. 相似文献
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为研究压气站失效与单台机组失效对输气管道的影响程度,采用SPS软件对压气站失效和单台机组失效进行了详细模拟。模拟结果显示:压气站失效与单台机组失效相比对管输系统影响较大;对于压气站失效,越靠近末站的压气站失效对管输系统影响越大;对于单台机组失效,越靠近首站的压缩机失效对管输系统影响越大。分析结果可为事故状态下的供气和抢修提供参考。 相似文献
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In the last decade, significant research efforts and technology have been dedicated to the development of microsimulation tools for a better representation of traffic systems. As a result, several commercial packages appeared and they are used nowadays in the detailed modelling of different transportation systems and operations for specific project evaluations and local designs, mostly within the urban context. After reviewing the specialized literature, we realized that most of these microsimulation tools are oriented to the movement of cars, leaving the public transportation systems as a complement, just for a realistic representation of the transportation system as a whole, but always oriented to simulate cars. In this paper, the objective is to provide guidelines on how to incorporate the necessary entities and components for a proper simulation of public transport systems in a microsimulation environment. Thus, the different approaches to simulate transit systems at a microlevel are discussed, highlighting the necessity of including stops, passengers and transit vehicles explicitly as entities within the microsimulation environment, for modelling transfer operations, control strategies, etc. Several examples are then provided to quantify the impact of such representations, for different cases and potential simulation platforms. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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对已建成的长距离输气管道,可通过增设压气站的方法来增加管道的输量,随着压气站数的增加,管道的输量增大,管道的经济效益增加,但当输量增大到一定值时,管道的经济效益要降低,因此,长距离输气管道存在着一个使管道的经济效益最大的最优输量。以内部收益率为评价指标,分别计算各个方案的内部收益率,作出内部收益率与管道输量的关系曲线,内部收益率最大的方案所对应的输量就是长距离输气管道的最优输量。最后以一条输气管道为例进行了实例计算。 相似文献