期刊文献+
共找到47篇文章
< 1 2 3 >
每页显示 20 50 100
机组初参数与热耗修正曲线的变工况计算法 被引量:18
1
作者 周兰欣 华敏 +2 位作者 王为 赵广春 赵庆丰 《动力工程学报》 CAS CSCD 北大核心 2011年第5期387-390,396,共5页
以汽轮机变工况理论为基础,假设保持调节级阀门开度不变的工况下,结合热力系统计算,建立了主蒸汽参数变工况计算模型,并以某600 MW机组为例,采用Matlab软件编程,计算得到了THA工况下机组主蒸汽压力和温度的热耗修正曲线.结果表明:用该... 以汽轮机变工况理论为基础,假设保持调节级阀门开度不变的工况下,结合热力系统计算,建立了主蒸汽参数变工况计算模型,并以某600 MW机组为例,采用Matlab软件编程,计算得到了THA工况下机组主蒸汽压力和温度的热耗修正曲线.结果表明:用该模型计算得到的热耗修正曲线与汽轮机制造厂提供的相比误差较小,且计算简单方便,能够满足工程实际的需要. 展开更多
关键词 主蒸汽参数 汽轮机变 修正曲线 率验收
下载PDF
水泵站耗能工况分析 被引量:2
2
作者 白春香 《鞍钢技术》 CAS 1999年第1期25-28,共4页
随着国民经济的不断发展,能源变得日趋紧张。在给排水系统中,水泵也是耗能大户,通过对水泵耗能、效率的计算和工况的分析,介绍了选择、调试水泵的一些可行性措施,以达到低耗、高效、节约能源的目的。
关键词 水泵站 节能 水泵 况分析
下载PDF
定人定机 机台核算 工耗挂钩
3
作者 张够花 《露天采矿技术》 CAS 2004年第3期45-46,共2页
孝义铝矿采矿车间采用“定人定机,机台核算,工耗挂钩”管理模式,使车间乃至孝义矿山整体管理水平不断上台阶,效果显著,是一套值得矿山企业借鉴的管理模式。
关键词 机台核算 挂钩 标准化
下载PDF
德州仪器计划于2005年第一季度推出采用创新型65纳米半导体工艺技术的样片
4
《电子与电脑》 2004年第4期142-142,共1页
关键词 德州仪器公司 65纳米技术 半导体 SOC设计 低功耗工世技术
下载PDF
高速ADC的电路结构及其速度—精度—功耗之间的权衡
5
作者 高工 《电子产品世界》 2001年第11期23-25,共3页
关键词 模数转换器 电路结构 速度 精度
下载PDF
600MW汽轮机凝汽器喉部数值模拟
6
作者 董倩茹 盛伟 《沈阳工程学院学报(自然科学版)》 2023年第1期36-41,共6页
根据600 MW汽轮机机组的凝汽器喉部建立物理及数学模型,同时考虑小机排汽的影响并在ANSYS软件中进行数值模拟。在100%、75%、50%THA(total hydrocarbons analyzer)工况下,对凝汽器喉部的汽动性能、静压恢复系数、喉部汽阻及总压损失系... 根据600 MW汽轮机机组的凝汽器喉部建立物理及数学模型,同时考虑小机排汽的影响并在ANSYS软件中进行数值模拟。在100%、75%、50%THA(total hydrocarbons analyzer)工况下,对凝汽器喉部的汽动性能、静压恢复系数、喉部汽阻及总压损失系数的分布规律进行分析可知:随着质量流量降低,凝汽器喉部出口的均匀性系数减小,出口静压恢复系数增大,总压损失系数降低,流场随着工况的改变逐渐恶化。此结果可为凝汽器喉部优化改造提供一定的理论基础。 展开更多
关键词 凝汽器喉部 率验收 数值分析
下载PDF
A New Cochlear Prosthetic System with an Implanted DSP 被引量:2
7
作者 麦宋平 张春 +1 位作者 晁军 王志华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1745-1752,共8页
This paper proposes a cochlear prosthetic system with an implanted digital signal processor (DSP). This system transmits voice-band signals with a low data rate through the wireless link, free of the data-rate limit... This paper proposes a cochlear prosthetic system with an implanted digital signal processor (DSP). This system transmits voice-band signals with a low data rate through the wireless link, free of the data-rate limitation and suitable for future development. By optimizing the speech processing algorithm and the DSP hardware design, the implanted DSP manages to execute the continuous interleaved sampling (CIS) algorithm at a clock frequency of 3MHz and a power consumption of only 1.91mW. With an analytic power-transmission efficiency of the wireless inductive link (40%), the power overhead caused by the implanted DSP is derived as 2.87roW,which is trivial when compared with the power consumption of existing cochlear prosthetic systems (tens of milliwatts). With the DSP implanted,this new system can.be easily developed into a fully implanted cochlear prosthesis. 展开更多
关键词 cochlear prosthesis low power algorithm optimization digital signal processor power-transmission efficiency
下载PDF
Hot deformation behavior of spray forming LSHR alloy using constitutive equation and processing map
8
作者 徐轶 汪杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第4期1032-1043,共12页
Flow behaviors of spray forming low solvus high refractory (LSHR) alloy were investigated using hot compression tests performed on a Gleeble?3500 thermal mechanical simulator at temperatures of 1020?1150 °C and s... Flow behaviors of spray forming low solvus high refractory (LSHR) alloy were investigated using hot compression tests performed on a Gleeble?3500 thermal mechanical simulator at temperatures of 1020?1150 °C and strain rates of 0.0003?1.0 s?1. The constitutive equation was established, power dissipation (η) maps and hot processing maps were plotted. The microstructure evolution and dislocation distribution of domains with different values of η in power dissipation maps were also observed. The results show that the flow stress increases with decreasing temperature and increasing strain rate. The activation energy of the spray forming LSHR alloy is 1243.86 kJ/mol. When the value of η is 0.36 at the strain of 0.5, the domain in the processing map shows characteristics of typical dynamic recrystallization (DRX) and low dislocation density. According to the microstructure evolution and processing maps, the optimum processing condition for good hot workability of spray forming LSHR alloy can be summed up as:temperature range 1110?1150 °C; strain rate range 0.01?0.3 s?1. 展开更多
关键词 low solvus high refractory alloy flow behavior WORKABILITY power dissipation map processing map dynamic recrystallization
下载PDF
Optimization of micro milling electrical discharge machining of Inconel 718 by Grey-Taguchi method 被引量:3
9
作者 林茂用 曹中丞 +3 位作者 许春耀 邱蕙 黄鹏丞 林裕城 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期661-666,共6页
The optimization of micro milling electrical discharge machining(EDM) process parameters of Inconel 718 alloy to achieve multiple performance characteristics such as low electrode wear,high material removal rate and... The optimization of micro milling electrical discharge machining(EDM) process parameters of Inconel 718 alloy to achieve multiple performance characteristics such as low electrode wear,high material removal rate and low working gap was investigated by the Grey-Taguchi method.The influences of peak current,pulse on-time,pulse off-time and spark gap on electrode wear(EW),material removal rate(MRR) and working gap(WG) in the micro milling electrical discharge machining of Inconel 718 were analyzed.The experimental results show that the electrode wear decreases from 5.6×10-9 to 5.2×10-9 mm3/min,the material removal rate increases from 0.47×10-8 to 1.68×10-8 mm3/min,and the working gap decreases from 1.27 to 1.19 μm under optimal micro milling electrical discharge machining process parameters.Hence,it is clearly shown that multiple performance characteristics can be improved by using the Grey-Taguchi method. 展开更多
关键词 Inconel 718 alloy micro milling electrical discharge machining electrode wear material removal rate working gap Grey-Taguchi method
下载PDF
分体式空调器能效提升方案设计及优化分析
10
作者 吕科磊 吕福俊 +1 位作者 杨文钧 张永刚 《轻工标准与质量》 2022年第5期103-105,共3页
通过分析印度当地ISEER能效标准确定设计目标。对换热器不可逆损失、火用效率和压缩机性能系数进行理论分析得出换热器大小和压缩机选型,并通过试验进行验证得出:增加冷凝器换热面积,可减少温差引起的不可逆损失和提高火用效率,但会降... 通过分析印度当地ISEER能效标准确定设计目标。对换热器不可逆损失、火用效率和压缩机性能系数进行理论分析得出换热器大小和压缩机选型,并通过试验进行验证得出:增加冷凝器换热面积,可减少温差引起的不可逆损失和提高火用效率,但会降低中间制冷能力能效,不利于整体ISEER的计算。换热能力充足时小压机更有利于印度能效ISEER的提升,单缸压机相对于双缸压机实际耗工更小。 展开更多
关键词 ISEER 不可逆损失 火用效率 耗工
下载PDF
蔷薇科植物嫁接技术研究
11
作者 谭成静 《现代农业科技》 2011年第21期214-215,共2页
从嫁接植株成活率、成活植株幼苗长势、耗时耗工量、操作复杂程度4个方面,对蔷薇科植物常用嫁接技术(劈接、插接、靠接)进行研究,结果表明,插接嫁接成活率高、成活植株长势好、省时省工、操作方法简单,优于劈接和靠接嫁接方式。
关键词 蔷薇科植物 嫁接技术 成活率 植株长势 耗工 操作复杂程度
下载PDF
如何计算废品损失
12
作者 鲁文章 《农村财务会计》 2003年第10期27-28,共2页
在审计企业财务收支中,如何计算废品损失是大伙经常碰到的难题,现将其计算方法作以浅析.
关键词 企业财务会计 废品损失计算方法 不可修复 耗工 定额成本 可修复
下载PDF
Pre-treatment of rocks prior to comminution--A critical review of present practices 被引量:7
13
作者 Somani Aditya Nandi Tapas K. +1 位作者 Pal Samir K. Majumder Arun K. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第2期339-348,共10页
It has been an established fact that comminution processes, crushing and grinding, are most energy intensive processes which account for more than half of the total energy consumed in mineral industries.Various altern... It has been an established fact that comminution processes, crushing and grinding, are most energy intensive processes which account for more than half of the total energy consumed in mineral industries.Various alternative pre-treatment methods have been tried by experts around the globe. Although these methods yielded positive results in terms of reduction in energy consumption in crushing and particularly, in grinding operations at laboratory scale, their industrial application still remains an unresolved issue and challenge. Present review paper describes each one of these methods along with outcome of earlier studies and issues that need to be addressed through further rigorous experimental investigation.It also suggests the direction in which future studies can be carried out to meet the primary objective of making comminution processes more energy efficient than today they are. 展开更多
关键词 Comminution Rock breakage Microwave Thermal shock
下载PDF
Oblique Wave Motion over Multiple Submerged Porous Bars near a Vertical Wall 被引量:3
14
作者 ZHAO Yang LIU Yong +1 位作者 LI Huajun CHANG Anteng 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第4期568-574,共7页
This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eige... This study examines oblique wave motion over multiple submerged porous bars in front of a vertical wall. Based on linear potential theory, an analytical solution for the present problem is developed using matched eigenfunction expansions. A complex dispersion relation is adopted to describe the wave elevation and energy dissipation over submerged porous bars. In the analytical solution, no limitations on the bar number, bar size, and spacing between adjacent bars are set. The convergence of the analytical solution is satisfactory, and the correctness of the analytical solution is confirmed by an independently developed multi-domain BEM (boundary element method) solution. Numerical examples are presented to examine the reflection and transmission coefficients of porous bars, CR and Cv, respectively, for engineering applications. The calculation results show that when the sum of widths for all the porous bars is fixed, increasing the bar number can significantly improve the sheltering function of the bars. Increasing the bar height can cause more wave energy dissipation and lower CR and Cr. The spacing between adjacent bars and the spacing between the last bar and the vertical wall are the key parameters affecting CR and Ct. The proposed analytical method may be used to analyze the hydrodynamic performance of submerged porous bars in preliminary engineering designs. 展开更多
关键词 multiple porous bars oblique wave vertical wall reflection coefficient transmission coefficient
下载PDF
Energy Dissipation with Geometric Parameters in Unbaffled Surface Aerator 被引量:1
15
作者 B. Kumar A.K. Patel A.R. Rao 《Journal of Environmental Science and Engineering》 2010年第2期80-84,共5页
The dissipation rate of turbulent kinetic energy ( ε ) is the key process parameters for mixing in surface aerators. At constant dynamic variables (rotational speed), ε is greatly affected by the geometric param... The dissipation rate of turbulent kinetic energy ( ε ) is the key process parameters for mixing in surface aerators. At constant dynamic variables (rotational speed), ε is greatly affected by the geometric parameters, such as impeller diameter, cross-sectional area of the tank, liquid height, rotor blade length and immersion height. By doing numerical computation by visimix, present work analyzes the effect of non-dimensional (which is non-dimensionalized through rotor diameter) geometric parameters on ε. With an increase in liquid height, there is an increase in the case of energy dissipation. In the case of tank area and blade length, it is vice versa. Energy dissipation is not affected by the variation in immersion height of the impeller. 展开更多
关键词 GEOMETRY energy dissipation MIXING surface aerator
下载PDF
Online fault recognition of electric power cable in coal mine based on the minimum risk neural network 被引量:2
16
作者 汪梅 STATHAKI Tania 《Journal of Coal Science & Engineering(China)》 2008年第3期492-496,共5页
Firstly,the concepts of the traveling wave entropy and the feature function of traveling wave entropy were defined.Then the statistic characters of the traveling wave entropy feature function,mean value and variance w... Firstly,the concepts of the traveling wave entropy and the feature function of traveling wave entropy were defined.Then the statistic characters of the traveling wave entropy feature function,mean value and variance were analyzed after the zero-order component of the traveling wave of online cable was selected to serve as the observed object.Finally,the new recognition algorithm of minimum risk neural network was pre- sented.The simulation experiments show that the recognitions of the early fault states can be completed correctly by using the proposed recognition algorithm.The classes of cable faults include in 1-phase ground faults,and the 2-phase short circuit faults or ground faults and the 3-phase short circuit faults or ground faults,open circuit.The fault resistance range is 1×10^(-1)~1×10~9Ω. 展开更多
关键词 minimum risk neural network traveling wave entropy zero-order component online cable recognition algorithm early fault
下载PDF
加强材料供应的管理 充分发挥其经济效能
17
作者 薛久安 辛建华 葛承祥 《中国城乡企业卫生》 2003年第3期5-5,共1页
加强对科室材料(卫生材料、一般用品)供应的科学管理,杜绝浪费,提高其经济效能并使之满足医疗活动需要,是医院后勤管理人员的重要职责.现就如何加强科室材料供应管理浅述如下:
关键词 材料供应 管理 经济效能 卫生材料 一般用品 医院 综合指数
下载PDF
An Approach towards Eco-labeling of Compressed Air Filters Based on Carbon Footprint
18
作者 Wolfgang Molter-Siemens Sebastian Kasselmann +1 位作者 Sebastian Berlin Christof Asbach 《Journal of Environmental Science and Engineering(B)》 2016年第2期57-68,共12页
Compressed air--a major industrial energy carrier, its filters are used to reach the required cleanliness level of compressed air. These filters, however, introduce a pressure drop which results in a loss of energy. I... Compressed air--a major industrial energy carrier, its filters are used to reach the required cleanliness level of compressed air. These filters, however, introduce a pressure drop which results in a loss of energy. It is shown that over the life cycle of a compressed air filter, the pressure drop dominates the total energy consumption and subsequently, the carbon footprint. From an economic as well as ecologic point of view, a reduction of the pressure drop is hence of utmost importance. Based on this finding and structuring, the wide range of applications and operational parameters, a pragmatic and technically feasible eco-labeling system for compressed air filters was developed as a decision supporting tool. Using this tool, procurement managers as well as the process engineers and environmental officers are able to steer the selection of suitable compressed air filters. The approach has been proposed to and discussed with various representatives of the compressed air filter industry nevertheless there is probably a long way to go to establish such a labeling procedure in industry. 展开更多
关键词 Eco-labeling carbon foot print life cycle assessment compressed air filters and product category rules
下载PDF
Industrial Carbon Emissions Status and Analysis Based on Energy Consumption
19
作者 Cao Zi Shen Zhenyao 《Chinese Journal of Population,Resources and Environment》 2011年第1期33-41,共9页
With frequent disastrous weathers and increasingly prominent GHG effects in recent years, normal existence and development of mankind are facing unprecedented threats and challenges. GHG emissions mitigation for the g... With frequent disastrous weathers and increasingly prominent GHG effects in recent years, normal existence and development of mankind are facing unprecedented threats and challenges. GHG emissions mitigation for the global climate changes has been the focus of concern of the world. As the biggest developing country and the second largest country of carbon-emission, China attaches importance to the carbon emission reduction. The major GHG component is carbon dioxide and in China, the emis- sion of carbon dioxide is mainly from industrial production. In the paper, the status and trend of Coz emission from industrial departments, high-carbon emission and its specific industries are shown in statistics. Meanwhile, the policy environment, industrial organization structure and technology of carbon high emission are all discussed based on practical situations in these departments and industries. At the end, through the analysis of gray correlation, correlativity is explored for both fossil energy consumption and total carbon emission, and also for the production value and carbon emission of each industrial sector. Some policy proposals for the establishment of low-carbon industries and transition of economic development pattern are set forth. 展开更多
关键词 industrial carbon emissions carbon intensity gray correlation emission reduction approach
下载PDF
Comparing material wastage levels between conventional in-situ and prefabrication construction in Hong Kong
20
作者 Vivian W YTam C M Tam L Y Shen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第5期548-551,共4页
Generation of construction wastes constitutes a major impact to the environment. Studies have been directed toward reducing wastes of the various construction processes. However, contractors in Hong Kong are rather co... Generation of construction wastes constitutes a major impact to the environment. Studies have been directed toward reducing wastes of the various construction processes. However, contractors in Hong Kong are rather conservative and lack motivation to develop new technology for waste minimization. This paper examines the benefits of using prefabrication in reducing material wastage levels for some traditional in-situ trades such as concreting, rebar fixing, bricklaying, drywall, plastering, screeding and tiling in Hong Kong. By measuring thirty construction projects, it is been found that waste levels of all major construction trades can be effectively reduced. This is particularly significant in the trade of plastering where 100% saving can be achieved after adopting prefabrication. The standardized design of the building can also be useful in the adoption of prefabrication for private housing projects. 展开更多
关键词 PREFABRICATION conventional in-situ trades material wastage environment
下载PDF
上一页 1 2 3 下一页 到第
使用帮助 返回顶部