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ANALYSES　OF　ENERGY　LOSSES　AND　accumulator　AND　PARAMETERS　DESIGN　METHOD　OF　HYDRAULIC　IMPACTOR　MECHANISM

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中国有色金属学会会刊：英文版 1995年第3期5卷 140-146页

作者： Qinghua, He Central South Univ of Technology Changsha China

ＡＮＡＬＹＳＥＳＯＦＥＮＥＲＧＹＬＯＳＳＥＳＡＮＤＡＣＣＵＭＵＬＡＴＯＲＡＮＤＰＡＲＡＭＥＴＥＲＳＤＥＳＩＧＮＭＥＴＨＯＤＯＦＨＹＤＲＡＵＬＩＣＩＭＰＡＣＴＯＲＭＥＣＨＡＮＩＳＭ￥Ｈｅ，Ｑｉｎｇｈｕａ（Ｄｅｐａｒｔｍ... 详细信息

ＡＮＡＬＹＳＥＳＯＦＥＮＥＲＧＹＬＯＳＳＥＳＡＮＤＡＣＣＵＭＵＬＡＴＯＲＡＮＤＰＡＲＡＭＥＴＥＲＳＤＥＳＩＧＮＭＥＴＨＯＤＯＦＨＹＤＲＡＵＬＩＣＩＭＰＡＣＴＯＲＭＥＣＨＡＮＩＳＭ￥Ｈｅ，Ｑｉｎｇｈｕａ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎ...

关键词： volume efficiency mechanical efficiency total efficiency accumulator design

MOTION ANALYSIS AND DESIGN OF accumulator FOR HYDRAULIC ROCK DRILL

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中国有色金属学会会刊：英文版 1996年第2期6卷 148-151页

作者： Liu Shixun(College of Mechanical and Electrical Engineering, Central South University of Technology, Changsha 410083) CENT S UNIV TECHNOL COLL MECH & ELECT ENGNCHANGSHA 410083PEOPLES R CHINA

ＭＯＴＩＯＮＡＮＡＬＹＳＩＳＡＮＤＤＥＳＩＧＮＯＦＡＣＣＵＭＵＬＡＴＯＲＦＯＲＨＹＤＲＡＵＬＩＣＲＯＣＫＤＲＩＬＬＬｉｕＳｈｉｘｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉ... 详细信息

ＭＯＴＩＯＮＡＮＡＬＹＳＩＳＡＮＤＤＥＳＩＧＮＯＦＡＣＣＵＭＵＬＡＴＯＲＦＯＲＨＹＤＲＡＵＬＩＣＲＯＣＫＤＲＩＬＬＬｉｕＳｈｉｘｕｎ（ＣｏｌｌｅｇｅｏｆＭｅｃｈａｎｉｃａｌａｎｄＥｌｅｃｔｒｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎ...

关键词： hydraulic accumulator diaphragm service life stretching ratio parameter design,motion analvsis

Dynamic characteristics of hydraulic power steering system with accumulator in load-haul-dump vehicle

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Journal of Central South University of Technology 2004年第4期11卷 451-456页

作者：杨忠炯何清华柳波 School of Mechanical and Electrical Engineering Central South University Changsha 410083 China

Using hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle as a simulation example, the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle were simulated and discussed with SIMULINK software and hydraulic control theory. The results show that the dynamic characteristics of hydraulic power steering system are improved obviously by using bladder accumulator, the hydraulic power steering system of model EIMCO 922 load-haul-dump vehicle generates vibration at the initial stage under the normal steering condition of pulse input, and its static response time is 0.25 s shorter than that without bladder accumulator. Under the normal steering working condition, the capacity of steering accumulator for absorbing pulse is directly proportional to the cross section area of connecting pipeline, and inversely proportional to the length of connecting pipeline. At the same time, the precharge pressure of nitrogen in steering accumulator should be 60%80% of the rated minimum working pressure of hydraulic power steering system. Under the abnormal steering working condition, the steering cylinder piston may obtain higher motion velocity, and the dynamic response velocity of hydraulic power steering system can be increased by reducing the pressure drop of hydraulic pipelines between the accumulator and steering cylinder and by increasing the rated pressure of hydraulic power steering system, but the dynamic characteristics of hydraulic power steering system in load-haul-dump vehicle have nothing to do with the precharge pressure of nitrogen in steering accumulator.

关键词： load-haul-dump vehicle hydraulic power steering system accumulator dynamic characteristics (simulation)

Neutral and accumulator species in determining the spatial structure of tree species at different spatial scales

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Journal of Forestry Research 2019年第6期30卷 2175-2183页

作者： Jie Gao Chengyu Lü Yanhong Liu Forestry College of Beijing Forestry University

In 2014,a 40-ha undisturbed plot was established in the Beijing Songshan Nature *** spatial distribution and spatial associations of five dominant tree species of different height classes were examined using spatial point pattern analysis and the effects of these species on local community diversity assemblages were examined using the ISAR *** dominant species were characterized by an aggregated distribution at spatial scales of 0–50 *** smaller spatial scales,trees in larger height classes had significant positive and negative effects on the diversity of the lower height ***,at larger spatial scales this effect was *** small scales(0–10 m),accumulator species had positive effects on species diversity,maintained an over-representative proportion of diversity in their proximity,and supported the ecological niche *** the larger scale(10–50 m),neutral species were dominant and had positive effects on species diversity,though repeller species,which had negative effects on species diversity,also contributed to *** and accumulator species together determined local species diversity,but the relative importance of the two was closely related to spatial scale.A combination of the ecological niche theory and neutral processes together determines species coexistence and biodiversity of an undisturbed pine forest.

关键词： The 40-ha natural Chinese pine forest Spatial scale ISAR model Species coexistence Neutral and accumulator species

High-stage analog accumulator for TDI CMOS image sensors

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Journal of Semiconductors 2016年第2期37卷 105-115页

作者：李建新黄福军宗勇高静 School of Electronic Information Engineering Tianjin University

The impact of the parasitic phenomenon on the performance of the analog accumulator in TDI CMOS image sensor is analyzed and resolved. A 128-stage optimized accumulator based on 0.18-μm one-poly four-metal 3.3 V CMOS technology is designed and simulated. A charge injection effect from the top plate sampling is em- ployed to compensate the un-eliminated parasitics based on the accumulator with a decoupling switch, and then a calibration circuit is designed to restrain the mismatch and Process, Voltage and Temperature （PVT） variations. The post layout simulation indicates that the improved SNR of the accumulator upgrades from 17.835 to 21.067 dB, while an ideal value is 21.072 dB. In addition, the linearity of the accumulator is 99.62%. The simulation results of two extreme cases and Monte Carlo show that the mismatch and PVT variations are restrained by the calibration circuit. Furthermore, it is promising to design a higher stage accumulator based on the proposed structure.

关键词： accumulator signal-to-noise ratio (SNR) time delay integration (TDI) CMOS image sensor (CIS)

Testing Research of accumulator Performance in the Hydro-pneumatic Suspension of a Vehicle

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International Journal of Plant Engineering and Management 2001年第3期6卷 118-123页

作者： FENG Shi cai, XU Yong, LU Hong yu Industrial College of Xuzhou Normal University, Jiangsu 221011, P.R.China Industrial College of Xuzhou Normal University Jiangsu 221011P.R.China

Taking a 2.5 liter accumulator with hydro-pneumatic suspension in a CXP1032 crane made in Germany as the research object and taking both the overall-road simulative test-bed and the control equipment made by the Schenck Company of Germany as the testing instrument, the structure performance and mechanism are theoretically clarified and the variation of gas states are obtained. This illustrates the accumulating and releasing process of a 2.5 liter accumulator in a 32t crane in the real condition. The preliminary volume and pressure of accumulator would directly affect the stiffness performance of the hydro-pneumatic suspension in a vehicle.

关键词： hydro-pneumatic suspension accumulator performance testing changing expo-nent

Effects of accumulator on Stabilization of Direct Acting Poppet Valve and Its System

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International Journal of Mining Science and Technology 1998年第1期19卷 80-83页

作者：李中复

The effect of vibration attenuation hy installing accumulator for water pressure system with the direct acting poppet valve is studied. The influencing factors of accumulator on the stabilization of direct acing poppe... 详细信息

关键词： stability characteristic equation accumulator

Optimal Control of a Thermoelectric Generator Attached with a Latent Heat accumulator

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Journal of Power and Energy Engineering 2017年第4期5卷 1-8页

作者： Akira Tsuyoshi Department of Electrical Engineering Kobe City College of Technology Kobe Japan

Generally MPPT control (maximum power point tracking) is adopted to control of a thermoelectric generator. However, in the case of generation by use of a heat accumulator MPPT control cannot obtain maximum whole electrical output during the operation period. This is because the amount of heat stored in a heat accumulator is limited and easy to be exhausted rapidly by MPPT. Therefore MEPT (Maximum Efficiency Point Tracking) control should be developed to obtain maximum power from limited heat stored in the heat accumulator. When thermoelectric generator is used for waste heat recovery, conversion efficiency is quite difficult to be measured. This is due to time delay between the change of temperature profile in the thermoelectric generator and the change of heat medium temperature. Decrease of output current is desired to enlarge output because decrease of current decreases Peltier heat and improves efficiency of heat recovery. The experimental results indicate that current fluctuated by MPPT control causes loss of power output. We proposed the optimal control in which current is 10% smaller than one of MPPT control and evaluated it experimentally. We call this control scheme MEPT control. In this evaluation 500 W class thermoelectric generator, latent heat accumulator and the test facilities included 30 kW electric heater are utilized. Experimental result shows MEPT control exceeds MPPT in total electricity recovered from heat accumulator.

关键词： Thermoelectric Generator Heat accumulator MPPT MEPT

维普期刊数据库评论

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维普期刊数据库

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accumulator的风险定量问题研究

汕头大学学报（人文社会科学版） 2015年第6期31卷 69-74,97页

作者：陈尔瑞汕头大学商学院广东汕头515063

以深南电与国际投行对赌原油价格的accumulator合约为典型案例,通过对此复杂的结构期权重新进行分解和组合,构造出能用布莱克-斯科尔斯模型计算的新期权组合,并具体给出accumulator的一种风险定量计算方法。

关键词： accumulator 结构期权风险定量问题