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A new energy landscape paving heuristic for satellite module layouts

Frontiers of Information Technology & Electronic Engineering 2016年第10期17卷 1031-1043页

作者： Jing-fa LIU Juan huang Gang LI Wen-jie LIU Ting-zhao GUAN Liang HAO Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science & Technology Nanjing 210044 China School of Computer & Software Nanjing University of Information Science & Technology Nanjing 210044 China School of Mathematics and Statistics Nanfing University of Information Science & Technology Nanjing 210044 China Office of lnformationization Construction and Management Nanjing University of lnformation Science & Technology Nanjing 210044 China

This article describes a study of the satellite module layout problem （SMLP）, which is a three-dimensional （3D） layout optimization problem with performance constraints that has proved to be non-deterministic polynomial-time hard （NP-hard）. To deal with this problem, we convert it into an unconstrained optimization problem using a quasi-physical strategy and the penalty function method. The energy landscape paving （ELP） method is a class of Monte-Carlo-based global optimization algorithm that has been successfully applied to solve many optimization problems. ELP can search for low-energy layouts via a random walk in complex energy landscapes. However, when ELP falls into the narrow and deep valleys of an energy landscape, it is difficult to escape. By putting forward a new update mechanism of the histogram function in ELP, we obtain an improved ELP method which can overcome this drawback. By incorporating the gradient method with local search into the improved ELP method, a new global search optimization method, hELP, is proposed for SMLP. Two representative instances from the literature are tested. Computational results show that the proposed hELP algorithm is an effective method for solving SMLP with performance constraints.

关键词： Three-dimensional packing Energy landscape paving Layout optimization Performance constraints

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Constant Speed Control for Complex Cross-section Welding Using Robot Based on Angle Self-Test

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 260-268页

作者： XUE Long ZOU Yong huang Jiqiang huang Junfen TAO Xinghua HU Yanfeng Opto-Mechatronic Equipment Technology Beijing Area Major Laboratory Beijing Institute of Petrochemical Technology School of Automation Science and Electrical Engineering Beihang University SINOPEC Research Institute of Petroleum Engineering

Expandable profile liner（EPL） is a promising new oil well casing cementing technique, and welding is a major EPLs connection technology. Connection of EPL is still in the stage of manual welding so far, automatic welding technology is a hotspot of EPL which is one of the key technologies to be solved. A robot for automatic welding of＂8＂ type EPL is studied. Four quadrants of mathematical equations of the 8-shaped cross-section track of EPL, consisting of multiple arcs, are established. Mechanism program for complex cross-section welding of EPL based on angle detection is proposed according to characteristics of small size, small valleys, and large forming errors, etc. A welding velocity vector control model is established by linkage control of a welding vehicle, a small driven actuator, and a height tracking mechanism. A constant speed control model based on an angle and symmetrical analysis model of rectangular coordinate system for EPL is built. Constraint conditions of constant speed control between each section are analyzed with 4 sections in first quadrant as an example, and cooperation work mechanism of the welding vehicle and the small tracking actuator is established based on pressure detection. The constant speed control model using angle self-test can be used to avoid the need for a precise mathematical model for tracking control and to adapt manufacture and installation deviation of EPL workpiece. The model is able to solve constant speed and trajectory tracking problems of EPL cross-section welding. EPL seams welded by the studied robot are good in appearance, and non-destructive testing（NDT） shows the seams are good in quality with no welding defects. Bulge tests show that the maximum pressure of welded EPL is 35 MPa, which can fulfill expansion performance requirements.

关键词： expandable profile liner welding robot minitype driven actuator velocity vector model

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Welding Deviation Detection Algorithm Based on Extremum of Molten Pool Image Contour

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Chinese Journal of Mechanical Engineering 2016年第1期29卷 74-83页

作者： ZOU Yong JIANG Lipei LI Yunhua XUE Long huang Junfen huang Jiqiang College of Automation Science and Electrical Engineering Beihang University Optical Electromechanical Equipment Technology Key Laboratory of Beijing Beijing Institute of Petrochemical Technology

The welding deviation detection is the basis of robotic tracking welding, but the on-line real-time measurement of welding deviation is still not well solved by the existing methods. There is plenty of information in the gas metal arc welding（GMAW） molten pool images that is very important for the control of welding seam tracking. The physical meaning for the curvature extremum of molten pool contour is revealed by researching the molten pool images, that is, the deviation information points of welding wire center and the molten tip center are the maxima and the local maxima of the contour curvature, and the horizontal welding deviation is the position difference of these two extremum points. A new method of weld deviation detection is presented, including the process of preprocessing molten pool images, extracting and segmenting the contours, obtaining the contour extremum points, and calculating the welding deviation, etc. Extracting the contours is the premise, segmenting the contour lines is the foundation, and obtaining the contour extremum points is the key. The contour images can be extracted with the method of discrete dyadic wavelet transform, which is divided into two sub contours including welding wire and molten tip separately. The curvature value of each point of the two sub contour lines is calculated based on the approximate curvature formula of multi-points for plane curve, and the two points of the curvature extremum are the characteristics needed for the welding deviation calculation. The results of the tests and analyses show that the maximum error of the obtained on-line welding deviation is 2 pixels（0.16 ram）, and the algorithm is stable enough to meet the requirements of the pipeline in real-time control at a speed of less than 500 mm/min. The method can be applied to the on-line automatic welding deviation detection.

关键词： welding deviation welding seam tracking molten pool contour curvature extremum gas metal arc welding(GMAW)

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Glycylproline dipeptidyl aminopeptidase isoenzyme in diagnosis of primary hepatocellular carcinoma

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World Journal of Gastroenterology 2003年第4期9卷 710-713页

作者： Run-Zhou Ni jie-Fei huang Ming-Bing Xiao Mei Li Xian-Yong Meng Department of Gastroenterology,Affiliated Hospital of Nantong Medical College,Nantong 226001,Jiangsu Province,China Department of Gastroenterology Affiliated Hospital of Nantong Medical College Nantong 226001 Jiangsu Province China. nirz@***

AIM: To investigate the role of glycylproline dipeptidyl aminopeptidase (GPDA) isoenzyme in the diagnosis of primary hepatocellular carcinoma (PHC), especially in patients with negative alpha-fetoprotein (AFP).METHODS: A stage gradient polyacrylamide gel discontinuous electrophoresis system was developed to separate serum GPDA isoenzymes, which were determined in 102 patients with PHC, 45 cases with liver cirrhosis, 24cases with chronic hepatitis, 35 cases with benign liver spaceoccupying lesions, 20 cases with metastatic liver cancer and 50 cases with extra-hepatic cancer, as well as 80 healthy subjects. The relationships between GPDA isoenzymes and AFP, the sizes of tumors, as well as alanine aminotransferase (ALT) were also ***: Serum GPDA was separated into two isoenzymes,GPDA-S and GPDA-F. The former was positive in all subjects,while the latter was found mainly in majority of PHC (85.3 %)and a few cases with liver cirrhosis (11.1%), chronic hepatitis (33.3 %), metastatic liver cancer (15.0 %) and non-hepatic cancer (16.0 %). GPDA-F was negative in all healthy subjects and patients with benign liver space-occupying lesions,including abscess, cysts and angioma. There was no correlation between GPDA-F and AFP concentration or tumor size. GPDA-F was consistently positive and not correlated with ALT in PHC, but GPDA-F often converted to negative as decline of ALT in benign liver diseases. The electrophoretic migration of GPDA-F became sluggish after the treatment of ***: GPDA-F is a new useful serum marker for PHC. Measurement of serum GPDA-F is helpful in diagnosis of PHC, especially in patients with negative AFP. GPDA-F is one kind of glycoproteins rich in sialic acid.

关键词：原发性肝细胞癌肿瘤标志物早期诊断 GPDA α-胎蛋白同工酶丙氨酸转氨酶

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MBA:A market-based approach to data allocation and dynamic migration for cloud database

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Science China(Information Sciences) 2012年第9期55卷 1935-1948页

作者： huang Allen Microsoft SQL China R&D Center

With the coming shift to cloud computing,cloud database is emerging to provide database service over the *** the cloud-based environment,data are distributed at Internet scale and the system needs to handle a huge number of user queries simultaneously without *** data are distributed among the servers has a crucial impact on the query load distribution and the system response *** this paper,we propose a market-based control method,called MBA,to achieve query load balance via reasonable data *** MBA,database nodes are treated as traders in a market,and certain market rules are used to intelligently decide data allocation and *** built a prototype system and conducted extensive *** results show that the MBA method significantly improves system performance in terms of average query response time and fairness.

关键词： market-based control data distribution load balancing

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Impact of oceans on climate change in drylands

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Science China Earth Sciences 2019年第6期62卷 891-908页

作者： Xiaodan GUAN jieru MA Jianping huang Ruixin huang Lei ZHANG Zhuguo MA Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric Sciences Lanzhou University Woods Hole Oceanographic Institution State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric Physics Chinese Academy of Sciences

Drylands account for approximately 41% of the global total land area. Significant warming and rare precipitation in drylands result in a fragile ecology and deterioration of the living environment, making it more sensitive to global climate change. As an important regulator of the Earth's climate system, the oceans play a vital role in the process of climate change in drylands. In modern climate change in particular, the impact of marine activities on climate change in drylands cannot be neglected. This paper reviews the characteristics of climate change in drylands over the past 100 years, and summarizes the researches conducted on the impact of marine activities on these changes. The review focuses on the impact of the Pacific Decadal Oscillation(PDO), Atlantic Multidecadal Oscillation(AMO), El Ni?o and La Ni?a on climate change in drylands, and introduces the mechanisms by which different oceanic oscillation factors synergistically affect climate change in *** have shown that global drylands have experienced a significant intensification in warming in the past 100 years, which shows obvious characteristics of interdecadal dry/wet variations. The characteristics of these changes are closely related to the oscillatory factors of the oceanic interdecadal scale. Different phase combinations of oceanic oscillation factors significantly change the land-sea thermal contrast, which in turn affects the westerly jet, planetary wave and blocking frequency, resulting in changes in the temperature and dry/wet characteristics of drylands. With the intensification of climate change in drylands, the impact of marine activities on these regions will reveal new characteristics in the future, which will increase the uncertainty of future climate change in drylands and intensify the impact of these drylands on global climate.

关键词： Impact of oceans on climate change in drylands AMO

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Enduring Public Health Challenge: Air Pollution and the Potential Dominant Risks of Particulate Matter

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Environment & Health 2024年第1期2卷 1-2页

作者： Wenzhong huang Shanshan Li Yuming guo Climate Air Quality Research UnitSchool of Public Health and Preventive MedicineMonash UniversityMelbourneVictoria 3004Australia

As an enduring and topical issue since the 20th century,the associations of air pollution with human health have been explored by substantial *** adverse relationships between ambient air pollution and health have been generally well-established,especially for the elevated mortality risks associated with air pollution exposure in developed countries and regions.

关键词： pollution Pollution Particulate

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FlowTrace： measuring round-trip time and tracing path in software-defined networking with low communication overhead

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Frontiers of Information Technology & Electronic Engineering 2017年第2期18卷 206-219页

作者： Shuo WANG Jiao ZHANG Tao huang Jiang LIU Yun-jie LIU F. Richard YU State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory Shijiazhuang 050081 China Beijing Advanced Innovation Center for Future Internet Technology Beijing University of Technology Beijing 100124 China Department of Systems and Computer Engineering Carleton University Ottawa ON KIS 5B6 Canada

：In today＇s networks, load balancing and priority queues in switches are used to support various quality-of-service （QoS） features and provide preferential treatment to certain types of traffic. Traditionally, network operators use ‘traceroute＇ and ‘ping＇ to troubleshoot load balancing and QoS problems. However, these tools are not supported by the common OpenFlow-based switches in software-defined networking （SDN）. In addition, traceroute and ping have potential problems. Because load balancing mechanisms balance flows to different paths, it is impossible for these tools to send a single type of probe packet to find the forwarding paths of flows and measure latencies. Therefore, tracing flows＇ real forwarding paths is needed before measuring their latencies, and path tracing and latency measurement should be jointly considered. To this end, FlowTrace is proposed to find arbitrary flow paths and measure flow latencies in OpenFlow networks. FlowTrace collects all flow entries and calculates flow paths according to the collected flow entries. However, polling flow entries from switches will induce high overhead in the control plane of SDN. Therefore, a passive flow table collecting method with zero control plane overhead is proposed to address this problem. After finding flows＇ real forwarding paths, FlowTrace uses a new measurement method to measure the latencies of different flows. Results of experiments conducted in Mininet indicate that FlowTrace can correctly find flow paths and accurately measure the latencies of flows in different priority classes.

关键词： Software-defined networking Network monitoring Traceroute

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A priori bounds for a class of semi-linear degenerate elliptic equations

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Science China Mathematics 2014年第9期57卷 1911-1926页

作者： huang GengGeng School of Mathematical Sciences Fudan University

In this paper,we mainly discuss a priori bounds of the following degenerate elliptic equation,a^ ij（x）δij u＋b^ i（x）δiu＋f（x,u）=0,in Ω belong to belong toR^n,（＊）where a^ijδiφδjφ=0 on δΩ,andφis the defining function of δΩ.Imposing suitable conditions on the coefficients and f（x,u）,one can get the L^∞-estimates of（＊）via blow up method.

关键词： degenerate elliptic equations characteristic semi-linear elliptic equations

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二维位场在有源空间的解析延拓

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地球物理学报 2016年第2期59卷 704-710页

作者：黄宗理郭佳中国地质科学院地球深部探测中心北京100035 地下信息探测技术与仪器教育部重点实验室(中国地质大学北京)北京100083

位场的向下延拓对重、磁等位场资料的处理与解释具有重要意义,但现有的延拓方法在位场向下接近场源时会产生剧烈震荡,计算过程很不稳定,而且理论上都不能越过场源.本文在复数域里定义了一个具有位场和几何双重特性的新函数PFGR,提出了... 详细信息

位场的向下延拓对重、磁等位场资料的处理与解释具有重要意义,但现有的延拓方法在位场向下接近场源时会产生剧烈震荡,计算过程很不稳定,而且理论上都不能越过场源.本文在复数域里定义了一个具有位场和几何双重特性的新函数PFGR,提出了一套新的延拓方法,在理论上实现了位场在包含场源的下半空间里的解析延拓,经过模型试算验证,表明该方法可以延拓越过场源,准确确定场源奇点,计算过程稳定,对测量中的随机噪声也具有较好的抗干扰能力.

关键词：位场解析延拓有源空间

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