轿厢上行超速保护装置检验的问题浅析

轿厢上行超速保护装置是安装在曳引驱动电梯上的重要安全部件。是GB7588—2003《电梯制造与安装安全规范》新增加的重要内容之一。笔者结合对GB7588—2003的学习与检验工作实践谈谈曳引电梯上行超速保护装置的检验方法及检验中发现的问题。     

电梯上行超速保护的讨论

近年来我国的电梯冲顶事故不断出现,造成了建筑物、设备的损坏和人员的伤亡。由于在原国家标准GB7588-1995中未提出此项要求,因此国家新标准GB7588-2003《电梯制造与安装规范》中明确要求电梯上行超速保护装置,并进行了强制性规定。这一条款的制定无疑是进一步完善了电梯的安全保护系统。针对现行电梯存在的状况和出现的安全问题,下面简单讨论一下电梯上行超速保护的引起原因、保护装置的型式及其优缺点。     

轿厢上行超速保护装置检验的问题浅析

轿厢上行超速保护装置是安装在曳引驱动电梯上的重要安全部件.是GB 7588-2003《电梯制造与安装安全规范》新增加的重要内容之一.笔者结合对GB 7588-2003的学习与检验工作实践谈谈曳引电梯上行超速保护装置的检验方法及检验中发现的问题.     

论电梯制动器定期检验的方法及其思考

制动器作为电梯的一个重要安全部件,它的好坏将直接影响到电梯的安全运行。为此,GB7588-2003《电梯制造与安装安全规范》规定：电梯必须有制动系统,而且应具有一个常闭式机动制动器,即通电时制动器释放,不论动力失电或控制电源失电时应立即制动。因此,在电梯的安全检查中应引起足够的重视,应做到检验项目具体、到位、不漏项。     

关于电梯轿顶护栏设置的建议①

电梯轿顶作为维保作业人员工作作业平台，它的安全防护直接关系到堆保人员的生命安全，护栏的安全性变得尤为重要，根据GB7588-2003《电梯制造与安装安全规范》关于轿顶护栏的要求提出自己一点小小的建议。     

浅谈电梯制动器的电气控制

从GB7588-2003《电梯制造与安装安全规范》对电梯制动器电气控制的要求出发,分别对切断制动器电流的电气装置的数量、独立性以及控制要求进行了分析,从而可以正确判断电梯制动器的电气控制是否符合标准要求。     

浅谈电梯的手动紧急操作装置

随着电梯使用的日益频繁,电梯困人事故时有发生,而电梯紧急操作装置是电梯发生困人时对被困人员进行救援的重要工具。本文以GB7588-2003电梯制造与安装安全规范及TSG T7001-2009特种设备安全技术规范为依据,通过实例讲解了在检验当中电梯的手动紧急操作装置经常存在的问题及解决方法,供同行参考。     

电梯的节能改造

随着时间的推移,一些老旧电梯到了更新换代的时候,但是由于整体更换成本比较高而且其机械性能还是很好,并没有过多的磨损,所以只需要更换电气系统进行改造,使其符合最新的GB7588规范。而电梯在使用过程中成本最高的就是电能,该文主要根据电梯在使用过程中电梯曳引机是四象限运动的特点介绍一下最新的节能方法。     

中草药组合物对轿厢电梯按钮的清洁效果

为研究中草药组合物对轿厢电梯按钮的清洁效果,依据国标GB/T 27728-2011检测中草药组合物对电梯按钮有无腐蚀性,参考GB/T 9985-2000附录B、GB/T 27728-2011、GB/T 13174中规定的实验方法进行去污率实验,采用涂布平板计数法检测中草药组合物对电梯按钮的除菌率以及牛津杯抑菌圈法检测中草药组合物对四种常见病原菌的抑菌活性。结果表明:实验前后金属片质量变化均小于0.3mg;相较于标准溶液15.19%的去污率,中草药组合物对按钮去污率达26.36%;除菌率达到99.55%;对四种病原菌均有抑菌作用,其中对大肠杆菌的抑菌圈达到了28.5mm。结果显示中草药组合物对轿厢电梯按钮无腐蚀性,去污、抑菌能力强。     

对“火灾时电梯全部停于首层“之我见

《火灾自动报警系统设计规范》(GB50116-98)第6.3.1.9条规定:消防控制室在确认火灾后,应能控制电梯全部停于首层,并接收其反馈信号。第6.3.1.8条规定:消防控制室在确认火灾后,应能切断有关部位的非消防电源。在执行规范的过程中是否能达到预期效果呢?     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

英文诗歌中的喻类修辞

为了有助于提高英文爱好者的个人情操、文化素养和学习兴趣,以及专业人员对英语学习和研究进行多途径的探索,本文通过一些精选诗歌的引证和分析,着重论述了喻类修辞法在英文诗歌中的运用其及效果。     

Man Is Unable to Change the Miserable Life——Analysis of the Arrangement of Four Characters in The Glass Menagerie

Tennessee Williams is considered as one of the most important American playwrights since World War II.The Glass Menagerie is his first successful drama,which describes a tragic situation of family and means to say that Man is unable to change the miserable life,no matter whatever means he try,This essay focuses on the analysis of the arrangement of the four main characters:Laura.Amanda,Jim and Tom to reveal the theme.Laura is fragile.Amanda is brave.Jim is vital.Tom is sensible.And all of them develop and try the different means to struggle against life,but fail tragically.With the evidence,the paper comes to conclusion naturally that Man is unable to change the miserable life,and he dooms to fail.     

Characterization of root-nodulating bacteria on Retama raetam in arid Tunisian soils

The aim of this study is to investigate the diversity of Retama raetam root-nodule bacteria isolated from arid regions of Tunisia. Twelve isolates, chosen as representative for different 16S rRNA gene patterns, were characterized by 16S rRNA gene sequencing and phenotypic analysis. Isolates were assigned to Sinorhizobium, Rhizobium and Agrobacterium. Symbiotic properties of Sinorhizobium and Rhizobium isolates showed a large diversity in their capacity to infect their host plant and fix atmospheric nitrogen. Strain RK 22 identified as Rhizobium was the most effective isolate.     

An Affordable Accurate Evaluation of the Binding Conformations Predicted by Molecular Docking Studies in Bio-System

正Recently,docking has been widely used to predict the binding-modes of protein-inhibitors,when the crystal complexes structure was absent.Most docking algorithms are able to generate a large number of probable conformations,it,however,is difficult to effectively evaluate these docking poses and identify the most reasonable bindingmode.In the present study,on the basis of the crystallographic data of human 3-hydroxy-3-methylglutaryl coenzyme     

WIMAX与WI-FI技术分析及联合组网

介绍了WiMAX与Wi-Fi两种无线宽带接入技术,并对两者之间的关系及相互之间的影响做了对比及分析,并对WiMAX的关键技术进行了详细说明,最后对两者的联合组网方式做了简单的探讨。