木瓜煤矿导线电算表的开发与应用

阐述了利用EXCEL电子表格创建井下经纬仪导线计算表的方法及在矿山井下测量中的使用效果,有一定的推广价值。

利用Excel编制方型补偿器选型电算表

利用Excel电子表格提供的功能,可在一张表格中一次完成方形补偿器选型及弹性力计算。省去了热伸长计算、外伸臂及横梁查表以及弹性力计算等过程,管道多时尤其显出其优越性。表中设计了分组计算功能,当外管架上需要增减管道时,可在表格中预留位置,使得处在同一中心线上的补偿器集中显示,便于观察调整。表中设计了计算值及实际值,可根据理论计算结果直接选定实际需要的数据。由于设计了分组计算功能,为固定点推力计算提供了方便。表中还给出了所计算管道的固定支架最大间距,便于设计人员确定固定支架的位置。所有计算结果一目了然,使得查找、修改、校核更加方便。

Electronic Chart Display and Information System

This paper introduces the most advanced form of electronic chart display and information systems (ECDIS) which complies with the Performance Standards for ECDIS established by the International Maritime Organization (IMO) and the International Hydrographic Organization (IHO).It also describes the key features and the important functions of ECDIS.Then the future development of ECDIS in marine is discussed.

Density Functional Theory Study on Spin States of LaCoO3 at Room Temperature

The electronic structure of the perovskite LaCoO3 at room temperature structure （293 K） was calculated by using PBE, PBE＋U and HSE. Different spin configurations have been considered. Our calculations showed that the choice of the Hubbard U parameter in DFT＋U and mixing factor α in HSE significantly influenced the band gap as well as relative energies. For the spin exited states, the optimal value for U and α were 3.0 eV and 0.05, respectively. Our calculation also emphasized that when U〉5.0 eV, PBE＋U would lead to unreasonable electronic structure and energy order.

Genetic Algorithm-Based Redundancy Optimization Method for Smart Grid Communication Network

This paper proposes a redundancy optimization method for smart grid Advanced Metering Infrastructure(AMI) to realize economy and reliability targets.AMI is a crucial part of the smart grid to measure,collect,and analyze data about energy usage and power quality from customer premises.From the communication perspective,the AMI consists of smart meters,Home Area Network(HAN) gateways and data concentrators;in particular,the redundancy optimization problem focus on deciding which data concentrator needs redundancy.In order to solve the problem,we first develop a quantitative analysis model for the network economic loss caused by the data concentrator failures.Then,we establish a complete redundancy optimization model,which comprehensively consider the factors of reliability and economy.Finally,an advanced redundancy deployment method based on genetic algorithm(GA) is developed to solve the proposed problem.The simulation results testify that the proposed redundancy optimization method is capable to build a reliable and economic smart grid communication network.

Research on the Recognition Method of Electric Energy Meter Lead Title based on the Fuzzy Image Processing

This article puts forward an automatic recognition algorithm of electric energy meter lead seals： firstly, the image will be histogram equalization, smoothing, binaryzation pretreatment, then according to the image characteristics of text changes, the system can quickly and accurately segment image from complex background, finally the system extract different dimension and the feature of English and Arabia using digital projection transform coefficient method and to identify the corresponding number by BP neural network, solves the problem of automatic recognition of electric energy meter lead sealing.

Bilayered semiconductor graphene nanostructures with periodically arranged hexagonal holes

We present a theoretical study of new nanostructures based on bilayered graphene with periodically arranged hexagonal holes （bilayered graphene antidots）. Our ab initio calculations show that fabrication of hexagonal holes in bigraphene leads to connection of the neighboring edges of the two graphene layers with formation of a hollow carbon nanostructure sheet which displays a wide range of electronic properties （from semiconductor to metallic）, depending on the size of the holes and the distance between them. The results were additionally supported by wave packet dynamical transport calculations based on the numerical solution of the time-dependent Schr/Sdinger equation.

Investigation on Active Thermal Control Method with Pool Boiling Heat Transfer at Low Pressure

In order to maintain a desirable temperature level of electronic equipment at low pressure, the thermal control performance with pool boiling heat transfer of water was examined based on experimental measurement. The total setup was designed and performed to accomplish the experiment with the pressure range from 4.5 kPa to 20 kPa and the heat flux between 6 kW/m^2 and 20 kW/m^2. The chosen material of the heat surface was alu- minium alloy and the test cavity had the capability of varying the direction for the heat surface from vertical to horizontal directions. Through this study, the steady and transient temperature of the heat surface at different pressures and directions were obtained. Although the temperature non-uniformity of the heat surface from the centre to the edge could reach 10℃ for the aluminium alloy due to the varying pressures, the whole temperature results successfully satisfied with the thermal control requirements for electronic equipment, and the temperature control effect of the vertically oriented direction was better than that of the borizontally oriented direction. Moreover, the behaviour of bubbles generating and detaching from the heat surface was recorded by a high-resolution camera, so as to understand the pool boiling heat transfer mechanism at low-load heat flux. These pictures showed that the bubbles departure diameter becomes larger, and departure frequency was slower at low pressure, in contrast to 1.0 atm.