对覆冰绝缘子进行除冰的方法

采用大电流对覆冰线路进行融冰的方法早已人所共知，但该方法只能除去导线上的结冰，对清除绝缘子（包括杆塔）上的覆冰则是无能为力的。为解决这一难题，本文提出了采用带有送风管的电热风机以及通过原有输电线路为电热风机提供电源这一方法。该方法是将变电站内配电变压器低压侧临时与覆冰线路接通或采用发电车与导线接通等方式，将低压电源送到各基杆塔，所有杆塔上的工作人员将电热风机的电源线接在覆冰导线上，手持送风管使热风吹向覆冰绝缘子，这样可将绝缘子上的冰融化掉。上述电热风机同样适用于变电站内各种绝缘套管的除冰作业。     

高压输电线路防覆冰材料与工程技术研究

本文介绍了高压输电线路覆冰的形成机理、覆冰的种类及影响覆冰的因素,分析了输电线路冰害事故的成因,论述了线路覆冰所造成的主要危害,介绍了防覆冰材料与工程技术的研究现状以及主要方法,并对该项技术的应用前景进行了展望．为广大电力工作者提供借鉴。     

输电线路冰害事故及原因分析探讨

随着我国经济建设的不断深入,各行业对电力的需求也与日俱增,为了满足日益增长的电力需求,我国对各地区的输电线路建设也在不断的加强,但是由于近些年来冬季天气经常出现异常状况,造成了我国很多输电线路相继出现了冰害事故,这些事故给社会造成的直接或间接的经济损失都相当之大。因此,本文通过对我国的输电线路冰害形成的原因入手,针对我国冰覆发生的成因进行充分的分析,以设计与建设我国现有输电设备为基础,给出实际的解决办法和应对措施。     

探讨220kV输电导线覆冰的防治方法实践

伴随着目前社会经济的逐步发展,人们生活质量及生活水平逐步提高,对电力的需求量越来越多,要求越来越严格。最近几年,我国各个地区的温度普遍不稳定,在2008年,我国南方出现了罕见的雪灾,大多数220kV的输电导线都出现了覆冰情况,从而影响了供电的稳定性与安全性。所以,相关工作人员应对该问题进行深入研究,探究相应防治措施。本文简要探讨了220kV输电导线出现覆冰情况的原因,并分析了相应危害,探讨预防方法,目的在于保证民众的用电安全。     

防覆冰涂层设计制备及性能研究

介绍了固体表面覆冰及防覆冰机理、防覆冰涂层的制备与表征、防覆冰表面制备的技术难点,并展望了超疏水防覆冰涂层和复合涂层防覆冰在涂料等行业中的应用。     

南车时代新材推出国内首款防冰冻叶片

据报道，6月26日，由湖南省株洲时代新材科技股份有限公司研发的防冰冻风机叶片在云南泸西正式投产。这标志着南车时代新材已掌握了适应南方高原地区特殊气候的叶片研发技术，成为国内首家推出防冰冻型叶片的企业，为南车时代新材开拓高原地区的叶片市场赢得了有利条件。     

浅议电网冬季冰害的预防

为提高电网抵御自然灾害的能力,结合我国南方地区近年来电网遭受冰冻灾害事故统计和调研情况,分析了冰冻灾害事故的原因,提出了输电线路覆冰事故防治措施。     

高压输电线路覆冰倒塔非线性屈曲分析

本文以湖南地区挂靖线220KV输电线路覆冰倒塔为例,按原工程资料建立精细化输电塔-线体系有限元模型。依据三峡地区覆冰资料建立覆冰增长曲线,考虑水平垂直档距、高差、不均匀覆冰和风荷载影响,对覆冰和风荷载作用下输电塔-线体系进行非线性屈曲分析,计算出覆冰荷载以及风荷载与覆冰共同作用下输电塔结构的极限承载能力,分析了倒塔的主要原因。研究表明,过载和不均匀覆冰引起的不平衡张力以及风荷载是倒塔的主要原因,重冰区覆冰架空输电线路技术设计规程的荷载水平需要进一步提高。     

浅析送电线路覆冰防治措施

送电线路的覆冰灾害常常给国家造成巨大的损失,给人民的生产生活带来极大的影响。送电线路的覆冰和积雪严重威胁着电力网络及设备的安全运行,线路大面积覆冰常导致一些输电铁塔不堪重负而倒塔断线,使电力设施遭到毁灭性破坏,对电力系统的安全运行产生严重危害。本文主要对35kV送电线路故障线路的抢修,分析总结出其故障起因及修复方案,希望对以后有效预防该类故障,提高电网安全运行有所帮助。     

输变电导线覆冰事故及形成机理分析

输变电导线覆冰事故给人民生产生活造成严重损害,因此对导线覆冰机理的分析以及防除冰技术的研究就显得尤为重要。本文回顾了国内外典型的导线覆冰灾害及导线覆冰后可能引发的三类事故,介绍了导线覆冰的种类和性质,分析了导线覆冰的热力学过程和机理,总结了四种典型导线覆冰数学模型的优缺点,探讨了导线防除冰技术现状及发展趋势。     

凝固科学技术与材料

从凝固科学与实践发展的角度介绍了当前凝固材料体系的基本框架和凝固科学主要发展阶段的基本理论。作为材料科学与工程的基本组成，凝固科学技术正在现代科学理论的基础上针对传统材料的改性提高和新材料的发展需求，以控形、控构、控性为目标开展优质铸件的定向、晶体生长、快凝、深过冷及各种新型和超常领域凝固过程的研究，并介绍了其中某些方面和展望了可能的发展趋势。     

Development and challenges of planning and scheduling for petroleum and petrochemical production

Production planning and scheduling are becoming the core of production management, which support the decision of a petrochemical company. The optimization of production planning and scheduling is attempted by every refinery because it gains additional profit and stabilizes the daily production. The optimization problem considered in industry and academic research is of different levels of realism and complexity, thus increasing the gap. Operation research with mathematical programming is a conventional approach used to address the planning and scheduling problem. Additionally, modeling the processes, objectives, and constraints and developing the optimization algorithms are significant for industry and research. This paper introduces the perspective of production planning and scheduling from the development viewpoint.     

江澳两地高校文创设计的协同研究与商业实践

目的 探索江门世遗文化的传承、发展和转化的新思路,践行国家在《粤港澳大湾区发展规划》纲要中要求江门承担与港澳地区文化创意合作与开发任务的分工。方法 与澳门高校紧密合作,开展专业培训课程,以开平碉楼为例,从人文视角开展设计研究,梳理开平碉楼的文化脉络,把世遗文化的元素和其背后的文化融入文创产品中,提升文创产品的附加值,推动当地文创产业结构的变革。结果 两地高校构建了稳定的科研团队,开设长期有效的设计培训课程,与景区建立了研究协作关系,帮助景区构建了一套产销研的商业模式。结论 以跨区域高校合作为平台,以文创产品为抓手,依托江澳两地的资源优势,可以构建江门世遗文化全新的品牌形象,最终推动开平世遗文化的活化。     

Error and uncertainty in modeling and simulation

This article develops a general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs). A comprehensive, new view of the general phases of modeling and simulation is proposed, consisting of the following phases: conceptual modeling of the physical system, mathematical modeling of the conceptual model, discretization and algorithm selection for the mathematical model, computer programming of the discrete model, numerical solution of the computer program model, and representation of the numerical solution. Our view incorporates the modeling and simulation phases that are recognized in the systems engineering and operations research communities, but it adds phases that are specific to the numerical solution of PDEs. In each of these phases, general sources of uncertainty, both aleatory and epistemic, and error are identified. Our general framework is applicable to any numerical discretization procedure for solving ODEs or PDEs. To demonstrate this framework, we describe a system-level example: the flight of an unguided, rocket-boosted, aircraft-launched missile. This example is discussed in detail at each of the six phases of modeling and simulation. Two alternative models of the flight dynamics are considered, along with aleatory uncertainty of the initial mass of the missile and epistemic uncertainty in the thrust of the rocket motor. We also investigate the interaction of modeling uncertainties and numerical integration error in the solution of the ordinary differential equations for the flight dynamics.     

Density and viscosity of tetralin and trans-decalin

New measurements are reported for the density and viscosity of tetralin and trans-decalin. The density was determined from room temperature to 60°C for tetralin and to 95°C for trans-decalin. The kinematic viscosity was measured up to temperatures slightly above 100°C. Our results improve upon the values recommended by the American Petroleum Institute for these liquids.     

The Candela and Photometric and Radiometric Measurements

The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements.     

Creation and motion of dislocations and fracture in metal and silicon crystals

By making a step on one surface ( ) of a rectangular small paralellepiped copper crystal, dislocations could be created by the molecular dynamic method. The dislocation created was not a complete edge dislocation but a pair of Heidenreich-Shockley partial dislocations. Each time a dislocation was created, the stress on the surface was released. Small copper crystals having a notch were pulled (until fracture), compressed and buckled by use of the molecular dynamic method. An embedded atom potential was used to represent the interaction between atoms. Dislocations were created near the tip of the notch. A very sharp yield stress was observed. The results of high speed deformations of pure silicon small crystals using the molecular dynamics are presented. The results suggest that plastic deformation may be possible for the silicon with a high speed deformation even at room temperature. Another small size single crystal, the same size and the same surfaces, was compressed using molecular dynamic method. The surfaces are {110}, {112} and {111}. The compressed direction was [111]. It was found that silicon crystals are possible to be compressed with a high speed deformation. This may suggest that silicon may be plastically deformed with high speed deformation.     

SMC／BMC的回收与再利用

SMC／BMC废弃物对工业及环境造成了很大影响，指出了SMC／BMC回收再利用的紧迫性。通过对目前国际上SMC／BMC回收再利用的3种典型途径优缺点的对比，参照国外SMC／BMC回收再利用的先进方法，对我国SMC／BMC回收再利用提供了可行的建议．