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EXPERIMENTAL STUDY ON INFLUENCE OF SUPPLIED PRESSURE FLUCTUATION ON OUTPUT ARACTERISTIC OF PRESSURE CONTROL SYSTEM OF ROLLING MILL

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Chinese Journal of Mechanical Engineering 1998年第2期11卷 73-79页

作者： zhao jingyi Li Jiutong Wang Yiqun Yanshan University Yanshan Univ China

The infulence of supplied pressure fluctuation on output accuracy for the electro hydraulic pressure control system of the rolling mill is *** on the bond graph theory and experimental study,the relationship between the variation of system output pressure and the supplied pressure fluctuation and the influence of the system bandwidth on system output pressure are provided.A theoretical base for determining the allowable fluctuation range of pressure and accurate design of constant pressure source system is obtained.

关键词： Pressure fluctuation Pressure control system Bond graph

Bifunctional Salen-Cu（II） Complex as Efficient Catalyst for N-Arylation of Imidazoles and Suzuki-Miyaura Coupling Reactions

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Chemical Research in Chinese Universities 2015年第4期31卷 549-552页

作者： WANG Yi GAO jingyi zhao Mengdan LI Jiamei Faculty of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650500 P. R. China

Bifunctional Salen-Cu（II） complex catalyzed cross-coupling reactions of aryl halids with imidazoles or phenylboronic acid reagents have been developed as practical methods for C--N and C--C bond formation. The procedure tolerates aryl halides with various functional groups（such as methoxy, acetyl, nitrile, fluoro and nitro groups） and gives the corresponding coupling products in moderate to high yields. The catalyst remained active after fiye successive catalytic runs without loss in performance.

关键词： Salcn-Cu(II) complex Homogenous catalysis Cross-coupling N-Arylation

Hosting Capacity Evaluation Method for Power Distribution Networks Integrated with Electric Vehicles

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维普期刊数据库

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Journal of Modern Power Systems and Clean Energy 2023年第5期11卷 1564-1575页

作者： Wei Dai Cheng Wang Hui Hwang Goh jingyi zhao Jiangyi Jian IEEE School of Electrical Engineering Guangxi UniversityNanning 530000China

The large-scale deployment of electric vehicles(EVs) poses critical challenges to the secure and economic operation of power distribution networks(PDNs). Therefore, a method for evaluating the hosting capacity that enables a PDN to determine the EV chargeable area(EVCA) to satisfy the charging demand and ensure the secure operation is proposed in this paper. Specifically, the distribution system operator(DSO) serves as a public entity to manage the integration of EVs by determining the presence of the charging load in the EVCA. Hence, an EVCA optimization model is formulated on the basis of the coupling effect of the charging nodes to determine the range of the available charging power. In this model, nonlinear power flow equations and operational constraints are considered to maintain the solvability of the power flow of the PDN. Subsequently, a novel multipoint approximation technique is proposed to quickly search for the boundary points of the EVCA. In addition, the impact of the demand response(DR) mechanism on the hosting capacity is explored. The results show that the presence of the DR significantly enlarged the EVCA during peak hours, thus revealing the suitability of the DR mechanism as an important supplement to accommodate the EV charging load. The examined case studies demonstrate the effectiveness of the proposed model and show that the unmanaged allocation of the charging load impedes secure operation. Finally, the proposed method provides a reference for the allocation of the EV charging load and a reduction in the risk of line overloading.

关键词： Capacity evaluation demand response(DR) electric vehicle(EV) electric vehicle chargeable area(EVCA)

Health status assessment of axial piston pump under variable speed

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High Technology Letters 2020年第3期26卷 315-322页

作者： Guo Rui Li Hucheng zhao Zhiqian Zhang Rongbing zhao jingyi Gao Dianrong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power'Transmission and Control Yanshan UniversityQinhuangdao 066004P.R.China State key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027P.R.China Key Labratory of Advanced Forging&Stamping Teclnology and Science Yanshan UniversityQinhuangdao O66004P.R.China Hebei Key Laboratory of Special Delivery Equipment Yanshan University Qinhuangdao 066004P.R.China

The axial piston pump usually works under variable speed *** is important to evaluate the health status of the axial piston pump under the variable speed *** at the characteristic signals obtained under different wear levels of the port plate,a feature signal extraction method under variable speed conditions is ***,the combination of complete ensemble empirical mode decomposition with adaptive noise(CEEMDAN)energy spectrum and fast spectral kurtosis principle is used to accurately extract the intrinsic mode function(IMF)component containing the sensitive information of the degraded ***,the aspect ratio analysis method of the angle domain variational mode decomposition(VMD)is used to process the feature index containing the sensitive information of the degraded *** order to evaluate the health status of the axial piston pump under variable speed,the vibration reliability analysis method for axial piston pump based on Weibull proportional failure rate model is *** experimental results show that the proposed method can accurately evaluate the health status of the axial piston pump.

关键词： axial piston pump variable speed condition order ratio variational mode decomposition(VMD)in angle domain health status assessment

Research on adaptive anti-rollover control of kiloton bridge transporting and laying vehicles

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High Technology Letters 2017年第2期23卷 203-211页

作者：郭锐 Shi Yu Wang Chao Tian Yaya zhao jingyi Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science ( Yanshan University) College of Mechanical Engineering Yanshan University Qinhuangdao 066004 P. R. China Lianyungang Tianming Equipment Co. Ltd Lianyungang 222000 P. R. China

The SPMT construction method is a new rapid construction technology of large urban overpass with unblocked traffic,and unstability of SPMT construction method equipment cannot be accurately described due to the concrete beam size,irregular shape and complex transport conditions,which is called kiloton bridge transporting and laying *** anti-rollover performance of SPMT suspension system is studied,and vehicle side slip angle and load transfer rate(LTR) are regarded as the evaluation *** active suspension adaptive anti-rollover control model of SPMT,in which roll stability affected by the structural parameters and control parameters,is built based on fuzzy PID,and the effectiveness of the control method is verified through real vehicle test.

关键词： kiloton bridge transporting and laying vehicle SPMT construction method active suspension adaptive anti-rollover control

Research of refrigeration system for a new type of constant temperature hydraulic tank

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High Technology Letters 2016年第4期22卷 436-444页

作者：郭锐 Zhang Zhenmiao zhao jingyi Ning Chao Li Bingliang Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityKey Laboratory of Advanced Forging & Stamping Technology and Science ( Yanshan University) Lianyungang Tianming Equipment Co. Ltd

Different from the traditional hydraulic oil cooling method,a new type of constant temperature oil tank cooling system based on semiconductor refrigeration technology is designed. This paper studies the principle of semiconductor refrigeration and establishes a heat transfer model. Semiconductor cooler on piping refrigeration is simulated,and influence of the parameters on the outlet temperature,such as pipe pressure difference of inlet and outlet,pipe length,pipe radius,are gotten,and then hydraulic tank semiconductor refrigeration system is proposed. The semiconductor refrigeration system can control temperature at 37 ± 1°C.

关键词： refrigeration system constant temperature control semiconductor refrigeration technology hydraulic tank simulated analysis experimental study

Reliability evaluation of bladder accumulator with no failure data

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High Technology Letters 2018年第3期24卷 322-329页

作者：郭锐 Zhang Rongbing zhao jingyi Zhou Jinsheng Zhang Zhenmiao Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan UniversityKey Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) College of Mechanical Engineering (Yanshan University) Qinhuangdao YSU -Yihua Electrical and Mechanical Engineering Technology Research Institute Co. Ltd.

As a bladder accumulator is a high reliable and long life component in a hydraulic system,its cost is high and it takes a lot of time to test its reliability,therefore,a reliability test with small sample is performed,and no failure data is obtained using the method of fixed time truncation. In the case of Weibull distribution,a life reliability model of bladder energy storage is established by Bayesian method using the optimal confidence intervals method,a model of one-sided lower confidence intervals of the reliability and one-sided lower confidence intervals model of the reliability life are established. Results of experiments show that the evaluation method of no failure data under Weibull distribution is a good way to evaluate the reliability of the accumulator,which is convenient for engineering application,and the reliability of the accumulator has theoretical and practical significance.

关键词： bladder accumulator Weibull distribution fixed time truncation no failure data reliability assessment

Coupling and coordinated evolution characteristics of regional economy-energy-carbon emission multiple systems:A case study of main China's Basin

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Journal of Environmental Sciences 2024年第6期140卷 204-218页

作者： Lu Chen Xin Li jingyi zhao Xinyu Kang Lu Liu Minxi Wang Wu Chen College of Management Science Chengdu University of TechnologyChengdu 610051China SDU Life Cycle Engineering Department of Green TechnologyUniversity of Southern Denmark5230 OdenseDenmark

Comprehensive analysis of the Economy-Energy-Carbon Emission(EECE)system is beneficial for promoting sustainable social *** study analyzes the system development of major watersheds in China from 2010 to *** research fully considers the system’s internal and external inputs and outputs and proposes an evaluation index system for regional EECE coupling and coordinated ***,using the difference in system weight allocation to improve the coupling and coordination model,the study explores the dynamic system’s coupling and *** results show that(1)The development of the system structure is relatively stable,but the overall development status is not ideal;(2)The downstream of China’s main river basins has obvious economic advantages,while the energy system fluctuates *** efficiency of the carbon emission system will decrease in areas with rapid economic *** coupling and coordination level of the EECE system is better in the Yangtze River Basin than in the Yellow River Basin;(3)From the perspective of dynamic coordinated development,the main river basins have been divided into two states since 2012,but it is relatively stable *** dynamic coordination is often at a disadvantage in regions with rapid economic and energy development;(4)The coupling coordination degree of the two river basins has significant positive spatial *** provinces’significant spatial clustering characteristics of the coupling coordination degree are High-High ***-Low type provinces are mainly concentrated *** research process has certain reference significance for the collaborative governance of complex regional systems.

关键词： System structure Efficiency measure Coupling mechanism Dynamic coordination

Magnetic polyamidoamine dendrimers for magnetic separation and sensitive determination of organochlorine pesticides from water samples by high-performance liquid chromatography

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Journal of Environmental Sciences 2021年第4期33卷 64-73页

作者： Qingxiang Zhou Yalin Wu Yi Sun Xueying Sheng Yayan Tong Jinghan Guo Boyao Zhou jingyi zhao State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249China Beijing Municipal Research Institute of Environmental Protection Beijing 100037China

Organochlorine pesticides(OCPs)have received much attention due to their *** methods to monitor their residues in the environment are ***,magnetic polyamidoamine dendrimers were prepared by co-precipitation,Michael addition,and *** magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs—this feature was utilized to construct a sensitive tool for monitoring OCPs in water *** proposed method provided remarkable linearity from 0.1 to 500μg/L and satisfactory limits of detection from 0.012 to 0.029μg/*** spiked recoveries of the four target analytes were 91.8%-103.5%with relative standard deviations less than 4.5%.The magnetic materials had good *** results indicated that the resulting method was an efficient,easy,rapid,economical,and eco-friendly tool for monitoring OCPs in aqueous samples.

关键词： Organochlorine pesticides Magnetic PAMAM dendrimers Fe_(3)O_(4)nanoparticles