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Simulation Analysis of Factors Influencing Chiller EER

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Journal of Thermal Science 2014年第3期23卷 285-289页

作者： HAO Xuejun WANG tong Beijing University of Civil Engineering and Architecture

This study constructed a mathematic model of a variable frequency centrifugal chiller using Simulink software. By running the simulation, it was discovered that when the other factors are constant, the EER(Energy Efficiency Ratio) of the chiller increases with decreases in the temperature of the cooling water and increases in the temperature of the chilled water. The effect of changes in the cooling water temperature on the EER of the chiller is stronger than that of changes in the chilled water temperature. In addition, as the chiller load decreases, the EER increases until reaching a maximum, after which it decreases. Furthermore, the EER of chillers working under a constant flow rate is slightly higher than that of those working under varying flow rates.

关键词： Chiller Simulation EER

Spatio-temporal Pattern and Driving Forces of Comprehensive Agricultural Productivity in Jilin Province,China

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Chinese Geographical Science 2020年第3期30卷 493-504页

作者： LIU Yunda tong Lianjun Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chi-nese Academy of Sciences Beijing 100049China

Improving comprehensive agricultural productivity is an important measure to realize agricultural *** on the data from Jilin Statistical Yearbook,this study analyzed the spatial and temporal characteristics of comprehensive agricultural productivity discrepancy in the main agricultural production areas of Jilin Province,*** comprehensive agricultural productivity of 25 county-level administrative units were evaluated by a comprehensive index system based on five aspects which included 20 indicators from 2004 to *** pattern of the discrepancy was analyzed by the spatial differentiation indices and spatial convergence *** results were as follows:1) the overall comprehensive agricultural productivity was in a ’W-type’ rising trend;2) the discrepancy was in’inverted W-type’ trend;3) the spatial distribution characteristics were mainly discrete plaque and ’inverted V-type’;4) the formation of differences was forced by a combination of internal and external driving *** study demonstrates the effectiveness of rising agricultural productivity and the level of economic and social developments in different counties in Jilin Province.

关键词： spatio-temporal pattern comprehensive agricultural productivity spatial convergence/divergence driving forces Jilin Province,China

Risk forecasting and evaluating model of Environmental pollution accident

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Journal of Environmental Sciences 2005年第2期17卷 263-267页

作者： ZENGWei-hua CHENGSheng-tong SchoolofEnvironment StateKeyLaboratoryofEnvironmentalSimulationandPollutionControlBeijingNormalUniversityBeijing100875China DepartmentofEnvironmentalScienceandEngineering TsinghuaUniversityBeijing100084China

Environmental risk(ER) factors come from ER source and they are controlled by the primary control mechanism(PCM) of environmental risk, due to the self failures or the effects of external environment risk trigger mechanism, the PCM could not work regularly any more, then, the ER factors will release environmental space, and an ER field is formed up. The forming of ER field does not mean that any environmental pollution accident(EPA) will break out; only the ER receptors are exposed in the ER field and damaged seriously, the potential ER really turns into an actual EPA. Researching on the general laws of evolving from environmental risk to EPA, this paper bring forwards a relevant concept model of risk forecasting and evaluating of EPA. This model provides some scientific methods for risk evaluation, prevention and emergency response of EPA. This model not only enriches and develops the theory system of environment safety and emergency response, but also acts as an instruction for public safety, enterprise's safety management and emergency response of the accident.

关键词： environmental risk(ER) environmental pollution accident(EPA) ER evaluation ER field EPA damage field

Tailoring magnetism in semiconductors

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Science China(Physics,Mechanics & Astronomy) 2018年第6期61卷 91-93页

作者： Igor Zutic tong Zhou Department of Physics University at Buffalo State University of New York Buffalo NY 14260 USA

While logic devices in conventional electronics rely on the control of the charged carriers in the semiconductor chips, robust information storage in computer hard drives and magnetic random access memory is implemented using the carriers＇ spin in ferromagnetic metals. A long quest to realize magnetic semiconductors [1-3] can be simply summarized as： 1＋1〉2, in hope that combining the control of charge and spin in a single material would become more than just the sum of its separate parts （charge and spin） and enable new or improved functionalities [3].

关键词：半导体芯片磁力定制计算机硬盘铁磁性逻辑设备信息存储充电

A Robust Face Recognition Method Combining LBP with Multi-mirror Symmetry for Images with Various Face Interferences

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International Journal of Automation and computing 2019年第5期16卷 671-682页

作者： Shui-Guang tong Yuan-Yuan Huang Zhe-Ming tong State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityNo.38Zheda RoadHangzhou 310027China School of Mechanical Engineering Zhejiang UniversityNo.38Zheda RoadHangzhou 310027China

Face recognition(FR) is a practical application of pattern recognition(PR) and remains a compelling topic in the study of computer vision. However, in real-world FR systems, interferences in images, including illumination condition, occlusion, facial expression and pose variation, make the recognition task challenging. This study explored the impact of those interferences on FR performance and attempted to alleviate it by taking face symmetry into account. A novel and robust FR method was proposed by combining multi-mirror symmetry with local binary pattern(LBP), namely multi-mirror local binary pattern(MMLBP). To enhance FR performance with various interferences, the MMLBP can 1) adaptively compensate lighting under heterogeneous lighting conditions, and 2) generate extracted image features that are much closer to those under well-controlled conditions(i.e., frontal facial images without expression). Therefore, in contrast with the later variations of LBP, the symmetrical singular value decomposition representation(SSVDR) algorithm utilizing the facial symmetry and a state-of-art non-LBP method, the MMLBP method is shown to successfully handle various image interferences that are common in FR applications without preprocessing operation and a large number of training images. The proposed method was validated with four public data sets. According to our analysis, the MMLBP method was demonstrated to achieve robust performance regardless of image interferences.

关键词： Face recognition(FR) local binary pattern(LBP) facial symmetry image interferences multi-mirror average

Treatment of multisystem inflammatory syndrome in children

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World Journal of Pediatrics 2024年第4期20卷 325-339页

作者： tong tong Yi-Hua Jin Min Wang Fang-Qi Gong Department of Cardiology Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNo.3333 Binsheng RoadHangzhou 310052China

Background Multisystem inflammatory syndrome in children(MIS-C),a relatively uncommon but severe pediatric complication,is associated with coronavirus disease 2019(COVID-19).A variety of treatment approaches,including intravenous immunoglobulins(IVIGs),glucocorticoids(GCs)and biologic agents,such as anakinra and infliximab,have been described for the management of COVID-19-related *** therapy is also ***,a well-developed treatment system has not been established,and many issues remain *** recently published articles related to the treatment of MIS-C have been ***,in this review,we identified relevant articles published recently and summarized the treatment of MIS-C more comprehensively and *** sources We reviewed the literature on the treatment of MIS-C through 20 September *** PubMed/Medline,Web of Science,EMBASE,and Cochrane Library databases were searched with the combination of the terms"multisystem inflammatory syndrome","MIS-C","PIMS-TS","therapy","treatment","drug","IVIG","GCs","intravenous immunoglobulin","corticosteroids","biological agent",and"aspirin".Results The severity of MIS-C varies,and different treatment schemes should be used according to the specific *** research and data collection are vital to better understand the pathophysiology and optimal management of *** MIS-Cis a disease involving multiple systems and has great *** the accumulation of additional experience,we have garnered fresh insights into its treatment ***,there remains a critical need for greater standardization in treatment protocols,alongside the pressing necessity for more robust and meticulously conducted studies to deepen our understanding of these protocols.

关键词： Coronavirus disease 2019-Corticosteroids Intravenous immunoglobulin Multisystem inflammatory syndrome in children-Treatment

Worst-Case Finish Time Analysis for DAG-Based Applications in the Presence of Transient Faults

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Journal of Computer Science & Technology 2016年第2期31卷 267-283页

作者： Xiao-tong Cui Kai-Jie Wu tong-Quan Wei Hsing-Mean Sha Key Laboratory of Dependable Service Computing in Cyber Physical Society Chongqing University Chongqing 400014 China College of Computer Science Chongqing University Chongqing 400044 China Department of Computer Science and Technology East China Normal University Shanghai 200241 China

Tasks in hard real-time systems are required to meet preset deadlines, even in the presence of transient faults and hence the analysis of worst-case finish time （WCFT） must consider the extra time incurred by re-executing tasks that were faulty. Existing solutions can only estimate WCFT and usually result in significant under- or over-estimation. In this work, we conclude that a sufficient and necessary condition of a task set experiencing its WCFT is that its critical task incurs all expected transient faults. A method is presented to identify the critical task and WCFT in O（IVI ＋ IEI） where IVI and IEI are the number of tasks and dependencies between tasks, respectively. This method finds its application in testing the feasibility of directed acyclic graph （DAG） based task sets scheduled in a wide variety of fault-prone multi-processor systems, where the processors could be either homogeneous or heterogeneous, DVS-capable or DVS-incapable, etc. The common practices, which require the same time complexity as the proposed critical-task method, could either underestimate the worst case by up to 25%, or overestimate by 13%. Based on the proposed critical-task method, a simulated-annealing scheduling algorithm is developed to find the energy efficient fault-tolerant schedule for a given DAG task set. Experimental results show that the proposed critical-task method wins over a common practice by up to 40% in terms of energy saving.

关键词： fault tolerance worst-case analysis simulated annealing energy conservation dynamic voltage scaling (DVS)

Nanoscale Reciprocating Sliding Contacts of Textured Surfaces:Influence of Structure Parameters and Indentation Depth

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Chinese Journal of Mechanical Engineering 2018年第4期31卷 168-181页

作者： Rui-Ting tong Geng Liu Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical University

Textured surfaces are widely used in engineering components as they can improve tribological properties of sliding contacts, while the detailed behaviors of nanoscale reciprocating sliding contacts of textured surfaces are still lack of study. By using multiscale method, two dimensional nanoscale reciprocating sliding contacts of textured surfaces are investigated. The influence of indentation depth, texture shape, texture spacing, and tip radius on the average friction forces and the running-in stages is studied. The results show that the lowest indentation depth can make all the four textured surfaces reach steady state. Surfaces with right-angled trapezoid textures on the right side are better for reducing the running-in stage, and surfaces with right-angled trapezoid textures on the left side are better to reduce wear. Compared with other textured surfaces, the total average friction forces can be reduced by 82.94%–91.49% for the case of the contact between the tip with radius R = 60rand the isosceles trapezoid textured surface. Besides,the total average friction forces increase with the tip radii due to that bigger tip will induce higher contact areas. This research proposes a detailed study on nanoscale reciprocating sliding contacts of textured surfaces, to contribute to design textured surfaces, reduce friction and wear.

关键词： Nanoscale Reciprocating sliding contacts Textured surface Structure parameters Indentation depth

Two-Dimensional Aerodynamic Models of Insect Flight for Robotic Flapping Wing Mechanisms of Maximum Efficiency

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Journal of Bionic Engineering 2008年第1期5卷 1-11页

作者： Thien-tong Nguyen Doyoung Byun Department of Aeronautical Engineering Hochiminh City University of Technology Hochiminh City Vietnam Department of Aerospace Engineering Konkuk University Seoul 143-701 Korea

In the ＂modified quasi-steady＂ approach, two-dimensional （2D） aerodynamic models of flapping wing motions are analyzed with focus on different types of wing rotation and different positions of rotation axis to explain the force peak at the end of each half stroke. In this model, an additional velocity of the mid chord position due to rotation is superimposed on the translational relative velocity of air with respect to the wing. This modification produces augmented forces around the end of each stroke. For each case of the flapping wing motions with various combination of controlled translational and rotational velocities of the wing along inclined stroke planes with thin figure-of-eight trajectory, discussions focus on lift-drag evolution during one stroke cycle and efficiency of types of wing rotation. This ＂modified quasi-steady＂ approach provides a systematic analysis of various parameters and their effects on efficiency of flapping wing mechanism. Flapping mechanism with delayed rotation around quarter-chord axis is an efficient one and can be made simple by a passive rotation mechanism so that it can be useful for robotic application.

关键词： bionics modified quasi-steady approach insect flight hovering forward flight