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Influence of propagation direction on operation performance of rotating detonation combustor with turbine guide vane

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Defence Technology（防务技术） 2021年第5期17卷 1617-1624页

作者： Wan-li Wei Yu-wen Wu Chun-sheng Weng Quan Zheng National Key Laboratory of Transient Physics Nanjing University of Science and TechnologyNanjing210094China

Due to the pressure gain combustion characteristics,the rotating detonation combustor(RDC)can enhance thermodynamic cycle ***,the performance of gas-turbine engine can be further improved with this combustion *** the present study,the RDC operation performance with a turbine guide vane(TGV)is experimentally *** and air are used as propellants while hydrogen and air mass flow rate are about 16.1 g/s and 500 g/s and the equivalence ratio is about 1.0.A pre-detonator is used to ignite the ***-frequency dynamic pressure transducers and silicon pressure sensors are employed to measure pressure oscillations and static pressure in the combustion *** experimental results show that the steady propagation of rotating detonation wave(RDW)is observed in the combustion chamber and the mean propagation velocity is above 1650 m/s,reaching over 84%of theoretical Chapman-Jouguet detonation *** and counterclockwise propagation directions of RDW are *** clockwise propagation direction,the static pressure is about 15%higher in the combustor compared with counterclockwise propagation direction,but the RDW dominant frequency is *** the oblique shock wave propagates across the TGV,the pressure oscillations reduces *** addition,as the detonation products flow through the TGV,the static pressure drops up to 32%and 43%for clockwise and counterclockwise propagation process respectively.

关键词： Rotating detonation combustor Propagation direction Turbine guide vane operation performance

Empirical analysis of mass flow and operation performance of a full-scale biogas plant for human feces treatment

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International Journal of Agricultural and Biological Engineering 2017年第2期10卷 233-241页

作者： Zhang Duojiao Duan Na Lin Cong Zhang Yilin Xu Qiuzi Liu Zhidan Laboratory of Environment-Enhancing Energy(E2E) College of Water Resources and Civil EngineeringChina Agricultural UniversityBeijing 100083China

With the rapid development of urbanization in China,the existing municipal network cannot cover all areas and solve all human waste treatment *** plants,as an important nationally developmental strategy for cleaner energy production and environmental protection,have been widely used in many industrial and agricultural *** research analyzed the mass flow and operation performance in a biogas plant treating human feces at a practical rather than laboratory *** biogas plant operated on mesophilic semi-continuous mode at the organic loading rates(OLRs)of 0.56 kg volatile solid(VS)/(m³·d)and average total solid(TS)contents of 3.50%.Results showed that the average biogas production and methane yield were(145±10)m³/d and(471±17)m³CH4/(t VS),*** total feeding amount was 2555.0 *** these,there were 58.04 t biogas and 2496.97 t digestate,including 43.07 t solid residues and 2453.90 t liquid *** the full-scale biogas plant,anaerobic bacteria could acclimatize to high total ammonia nitrogen(TAN)concentration(3659 mg/L)and tolerate high free ammonia nitrogen(FAN)concentration of 561 mg/*** also had strong autoregulation for adapting the large range(2.02-15.18 g/L)and high concentration(15.18 g/L)of influent volatile fatty acid(VFA).In order to achieve its sustainable development and high efficient operation,it is very important to improve the feeding concentration,using digestate to dilute raw material and adding some high C/N raw material in human *** conclusion,the biogas plant was an excellent alternative technology for treating human feces.

关键词： biogas plant human feces mass flow operation performance methane

SEMG-based fighter pilot muscle fatigue analysis and operation performance research

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Medicine in Novel Technology and Devices 2022年第4期16卷 345-349页

作者： Biyun Zhou Bo Chen Huijuan Shi Lihao Xue Yingfang Ao Li Ding Beijing Advanced Innovation Center for Biomedical Engineering School of Biological Science and Medical EngineeringBeihang UniversityNo.37 XueYuan RoadHaiDian DistrictBeijing100191China Institute of Sports Medicine Peking University Third HospitalBeijing Key Laboratory of Sports InjuriesBeijing100191China Biomechanics Laboratory College of Human Movement Science Beijing Sport University Beijing100084China

Fatigue has a tremendously adverse impact on pilot *** study aims to explore the Biceps Brachii(BB),Rectus Femoris(RF),Flexor Carpi Radialis(FCR),and Tibialis Anterior(TA)activities of fighter pilots in the early and late combat stages,and the target hitting time.A total of 13 volunteers were recruited to conduct simulated combats inside a real fighter *** surface Electromyography(sEMG)was collected from all volunteers in the initial and final 20s of flight,and the target hitting time during three simulated combats was *** root mean square(RMS)values of right BB and TA were significantly higher than the left side values(poperational *** study provides a reference for fighter pilot fatigue protection and treatment.

关键词： Surface electromyography Flight fatigue operation performance Daubechies wavelet

The performance analysis and calculation for variable frequency speed control motors with the rotor structure optimized

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Journal of Harbin Institute of Technology(New Series) 2005年第6期12卷 710-714页

作者：曹君慈李伟力 The College of Electrical and Electron Engineering Harbin University of Science and Technology Harbin 150040China Dept. of Electrical Engineering Harbin Institute of Technology Harbin 150001China

In the paper, the method to optimize the rotor structure in variable frequency speed control motors is introduced. The saturation and the skin effect are considered and 2D no-load and load electromagnetic field is calculated in finite elements for a variable frequency speed control motor before and after optimization. Finally, no-load current and operation performance before and after optimization are obtained and the two results are contrasted.

关键词： variable frequency speed control optimization design finite element operation performance

USE OF COMPETITIONS AND CHALLENGES AS A MEANS OF IMPROVING OPERATOR performance AND RELIABILITY

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Transactions of Nanjing University of Aeronautics and Astronautics 1998年第1期15卷 121-127页

作者： Bradley E A (Chief Consultant, Eskom, Sandton, South Africa)

The main way they have of improving overall system reliability is to concentrate on human reliability if organizations are not installing new plant. Previous research by the author has shown that the main cause of system unreliability is operator unreliability. There are three main ways to deal with operator unreliability viz improve the environment, enhance the operator′s skill and increase his motivation. Of these, the last is the final untapped area for achieving significant gains in system reliability. Moves to do this by means of competitions for operators at both a local and international level are discussed, with a description of the successes so far.

关键词： system reliability competitions operation performance

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服务创新与物流O2O平台运作绩效

我国零售企业经营效率评价与微观影响因素分析

物流管理 2018年第8期

作者：耿勇

互联网+高效物流背景下，物流运营模式创新成为物流业降本增效和供给侧结构性改革的关键。物流O2O平台可以实现物流链的去中间化，达到物流供给侧与需求侧线上线下的融合与平衡。不过，我国物流O2O平台在快速发展的同时，其服务内容同... 详细信息

互联网+高效物流背景下，物流运营模式创新成为物流业降本增效和供给侧结构性改革的关键。物流O2O平台可以实现物流链的去中间化，达到物流供给侧与需求侧线上线下的融合与平衡。不过，我国物流O2O平台在快速发展的同时，其服务内容同质化与用户多归属现象严重，为提升平台运作绩效，必须进行服务创新。而物流O2O平台在物流服务创新及应用过程中，一定要重视新客户服务界面、新技术应用、新服务传递系统、新服务概念等方面。具体而言，就是要重视客户服务界面的特色化和差异化，特别是基于服务内容创新的界面体现；要提高技术水平，强化智慧设备在运营领域的应用，创新应用大数据、区块链、物联网等技术进行货运物流革新；要强化全员创新理念，注重创新传递系统建设；要重视企业内部创新意识形成，通过营造良好的学习环境和创新氛围，提升整体创新意识，促进服务创新对运作绩效的积极影响。

关键词：物流O2O平台服务创新运作绩效团队创新意识 logistics O2O platform service innovation operation performance team innovational consciousness

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贸易经济 2011年第10期

作者：樊秀峰王美霞

选取2009年中国百强零售企业中的22家上市公司为样本，首先通过收集其2009年年末从业人数、门店数、资产总额、经营费用、主营业务收入、净利润等指标进行DEA效率评价，评价结果显示，目前国内大部分零售业上市公司的运营结构不合理，... 详细信息

选取2009年中国百强零售企业中的22家上市公司为样本，首先通过收集其2009年年末从业人数、门店数、资产总额、经营费用、主营业务收入、净利润等指标进行DEA效率评价，评价结果显示，目前国内大部分零售业上市公司的运营结构不合理，资源配置效率较低，且大多数处于规模效率递增阶段。其次，运用Tobit模型对影响其效率的产权结构、股权结构、资本结构、企业盈利能力、上市时间长短等微观影响因素进行实证分析，结果表明，零售企业的净资产收益率、产权结构、资产负债率、公司上市时间等因素与上市公司的经营效率存在明显的相关性，股权集中度对企业的经营效率不会造成直接的影响。

关键词：零售企业经营效率微观影响因素上市公司技术效率 retail enterprise operation performance micro-influencing factors listed company technical efficiency

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基于渠道控制的市场势力构建模式特征分析