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Empirical Analysis on Urbanization Patterns in Zhejiang Province Based on Spatial Economy and GIS

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Chinese Geographical Science 2006年第3期16卷 193-198页

作者： GE Ying liang qi College of Civil Engineering Hohai University Nanjing 210098 China School of Business Nanjing University Nanjing 210093 China

Regional core cities are the growth poles for regional economic development, thus the issue about efficient urbanization pattern has always become a hot spot among researchers and policy makers. The Spatial Economy can be employed to improve it. Nevertheless, there actually exists an obvious gap between its theoretical models and the empirical simulation. To do so, this paper modifies the measurement of initial geographical advantages Stelder gave, and implements the empirical analyses of urban distribution in Zhejiang during the period of 1980-1990 by means of computer simulations in GIS environment. There are several interesting results achieved in this process. Firstly, given the values of parameters （transport cost is r, substitution elasticity of manufacturing sector p, and income share of spending on manufacture δ）, initial geographical advantages have the different impacts on urban systems, namely, urban locations, numbers and sizes over time across space. Secondly, the cities were distributed without any overlay in geographical space, which makes the patterns of urbanization generate the largest possible economic efficiencies. Thirdly, the urban systems-the location, number and size of Cities-from the simulation of the study area are suitable for the actual social and economic situations in the real world during the testing periods. Such results may have substantial implications for the policy how to choose the way of urbanization in a region.

关键词： urbanization pattern Spatial Economy empirical analysis GIS technique initial geographical advantage Zhejiang Province

Experimental investigation of laser-produced-plasma EUV source based on liquid target

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光学精密工程 2005年第5期13卷 604-607页

作者： qi Li-hong NI qi-liang CHEN Bo Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Institute of Atomic and Molecular Physics Jilin University Changch un 130026 China

A laser-produced plasma(LPP) source was built using liquid as target and a Nd:YAG laser as the irradiation laser, and the LPP source's radiation with ethanol and acetone target respectively was measured by an AXUV100 silicon photodiode combined with a McPHERSON model 247 grazing incidence monochromator of the resolution Δλ≤0.075 nm and the wavelength scanning interval 0.5 nm. Both ethanol and acetone target LPP source had EUV emission at 11～20 nm wavelength. The comparison between the spectra of the two kinds of target materials shows that all the two kinds of target source's spectra are the result of oxygen ions' transitions under current source's parameters, but the spectrum intensity from different target sources is different. The spectra intensity from the ethanol target is higher than that from the acetone target. In addition, the target liquid is forced into the vacuum chamber by the background pressure supported by the connected external high pressure gas, and the influence of the background pressure on the source's intensity is investigated.

关键词： LPP 激光等离子体亮度

Efficient Deviation Detection Between a Process Model and Event Logs

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1352-1364页

作者： Lu Wang Yuyue Du liang qi the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Shandong Province Key Laboratory of Wisdom Mine Information Technology Shandong University of Science and TechnologyQingdao 266590China

Business processes described by formal or semi-formal models are realized via information *** logs generated from these systems are probably not consistent with the existing models due to insufficient design of the information system or the system *** comparing an existing process model with event logs,we can detect inconsistencies called deviations,verify and extend the business process model,and accordingly improve the business *** this paper,some abnormal activities in business processes are formally defined based on Petri *** efficient approach to detect deviations between the process model and event logs is ***,business process models are revised when abnormal activities exist.A clinical process in a healthcare information system is used as a case study to illustrate our *** results show the effectiveness and efficiency of the proposed approach.

关键词： Detect deviations event log model repair Petri net process model

A User Requirement Oriented Web Service Discovery Approach Based on Logic and Threshold Petri Net

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IEEE/CAA Journal of Automatica Sinica 2019年第6期6卷 1528-1542页

作者： Jing Sha Yuyue Du liang qi Shandong University of Science and Technology Qingdao 266590China

In recent years, the number of Web services has increased significantly. Web service discovery has drawn much attention with the development of Web service applications and big data analysis. Under this circumstance, traditional Web service discovery strategies cannot adequately meet high user requirements due to the efficiency and precision of service discovery is low. In order to improve the accuracy and efficiency of service discovery, a user requirement oriented Web service discovery approach based on Petri nets is proposed in this study. A data preprocessing strategy of Web service is first designed. Then, a service clustering method is proposed based on Petri nets, which can conduct service cluster head generation, service cluster composition, and service discovery. The proposed method utilizes a superior data preprocessing method. Using simulation experiments,the efficiency and precision of Web service discovery are illustrated. Finally, the application value of the approach on real Web service is discussed.

关键词： Petri net(PN) service cluster head service clustering service discovery Web service

A Dynamic Road Incident Information Delivery Strategy to Reduce Urban Traffic Congestion

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 934-945页

作者： liang qi Mengchu Zhou Wenjing Luan IEEE Department of Computer Scicnce and Technology Shandong University of Science and TechnologyQingdao 266590China Department of Computer Science Tongji UniversityShanghai 201804China Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewark NJ 07102USA Key Laboratory of Embedded System and Service Computing Ministry of EducationShanghai Electronic Transactions and Information Service Collaborative Innovation CenterDepartment of Com-puter ScienceTongji UniversityShanghai 201804China

Advanced information and communication technolo-gies can be used to facilitate traffic incident *** an incident is detected and blocks a road link,in order to reduce the incident-induced traffic congestion,a dynamic strategy to deliver incident information to selected drivers and help them make detours in urban areas is proposed by this ***-dependent shortest path algorithms are used to generate a subnetwork where vehicles should receive such information.A simulation approach based on an extended cell transmission model is used to describe traffic flow in urban networks where path information and traffic flow at downstream road links are well *** results reveal the influences of some major parameters of an incident-induced congestion dissipation process such as the ratio of route-changing vehicles to the total vehicles,operation time interval of the proposed strategy,traffic density in the traffic network,and the scope of the area where traffic incident information is *** results can be used to improve the state of the art in preventing urban road traffic congestion caused by incidents.

关键词： Cell transmission model(CTM) intelligent transportation systems(ITS) traffic incident management(TIM) urban traffic congestion

Solar cycle prediction using a long short-term memory deep learning model

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Research in Astronomy and Astrophysics 2021年第1期21卷 119-126页

作者： qi-Jie Wang Jia-Chen Li liang-qi Guo School of Geosciences and Info-Physics Central South UniversityChangsha 410083China

In this paper,we propose a long short-term memory(LSTM)deep learning model to deal with the smoothed monthly sunspot number(SSN),aiming to address the problem whereby the prediction results of the existing sunspot prediction methods are not uniform and have large *** method optimizes the number of hidden nodes and batch sizes of the LSTM network structures to 19 and 20,*** best length of time series and the value of the timesteps were then determined for the network training,and one-step and multi-step predictions for Cycle 22 to Cycle 24 were made using the well-established *** results showed that the maximum root-mean-square error(RMSE)of the one-step prediction model was6.12 and the minimum was only *** maximum amplitude prediction error of the multi-step prediction was 17.2%and the minimum was only 3.0%.Finally,the next solar cycles(Cycle 25)peak amplitude was predicted to occur around 2023,with a peak value of about *** accuracy of this prediction method is better than that of the other commonly used methods,and the method has high applicability.

关键词： Sun:solar activity Sun:sunspot number techniques:deep learning techniques:long short-term memory

Formation of I1 stacking fault by deformation defect evolution from grain boundaries in Mg

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Journal of Magnesium and Alloys 2022年第10期10卷 2717-2729页

作者： Yong-Jie Hu Vaidehi Menon liang qi Department of Materials Science and Engineering University of MichiganAnn Arbor 48109USA Department of Materials Science and Engineering Drexel UniversityPhiladelphia 19104USA

I_(1)stacking faults(SFs)in Mg alloys are regarded as the nucleation sites ofdislocations that are critical for these alloys to achieve high *** it was proposed that the formation of I_(1)SFs requires the accumulations of a large number of vacancies,which are difficult to achieve at low *** this study,molecular dynamics(MD)and molecular statics(MS)simulations based on empirical interatomic potentials were applied to investigate the deformation defect evolutions from the symmetric tilt grain boundaries(GBs)in Mg and Mg-Y alloys under external loading along-*** results show the planar faults(PFs)on Pyramidal I planes first appear due to the nucleation and glide of(1/2 c+p)partial dislocations from GBs,where p=1/3(1010).These partial dislocations with pyramidal PFs interact with other defects,including pyramidal PFs themselves,GBs,and ppartial dislocations,generating a large amount of I_(1)*** analyses show the nucleation and growth of I_(1)SFs are achieved by atomic shuffle events and deformation defect reactions without the requirements of vacancy *** simulations also suggest the Y clusters at GBs can reduce the critical stress for the formation of pyramidal PFs and I_(1)SFs,which provide a possible reason for the experimental observations that Y promotes thedislocation activities.

关键词： Magnesium alloys I1 stacking faults dislocations Grain boundaries Defect nucleation and evolution Molecular dynamics simulations

Trace Element Geochemistry of Magnetite from the Fe(-Cu) Deposits in the Hami Region, Eastern Tianshan Orogenic Belt, NW China

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 176-195页

作者： HUANG Xiaowen qi liang MENG Yumiao State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Laser ablation–inductively coupled plasma–mass spectrometry（LA–ICP–MS） was used to determine the trace element concentrations of magnetite from the Heifengshan, Shuangfengshan, and Shaquanzi Fe（–Cu） deposits in the Eastern Tianshan Orogenic Belt. The magnetite from these deposits typically contains detectable Mg, Al, Ti, V, Cr, Mn, Co, Ni, Zn and Ga. The trace element contents in magnetite generally vary less than one order of magnitude. The subtle variations of trace element concentrations within a magnetite grain and between the magnetite grains in the same sample probably indicate local inhomogeneity of ore–forming fluids. The variations of Co in magnetite between samples are probably due to the mineral proportion of magnetite and pyrite. Factor analysis has discriminated three types of magnetite： Ni–Mn–V–Ti（Factor 1）, Mg–Al–Zn（Factor 2）, and Ga– Co（Factor 3） magnetite. Magnetite from the Heifengshan and Shuangfengshan Fe deposits has similar normalized trace element spider patterns and cannot be discriminated according to these factors. However, magnetite from the Shaquanzi Fe–Cu deposit has affinity to Factor 2 with lower Mg and Al but higher Zn concentrations, indicating that the ore–forming fluids responsible for the Fe–Cu deposit are different from those for Fe deposits. Chemical composition of magnetite indicates that magnetite from these Fe（–Cu） deposits was formed by hydrothermal processes rather than magmatic differentiation. The formation of these Fe（–Cu） deposits may be related to felsic magmatism.

关键词： trace elements magnetite LA–ICP–MS Fe(–Cu) deposits Eastern Tianshan Orogenic Belt Xinjiang

Partition-based Collaborative Tensor Factorization for POI Recommendation

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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 437-446页

作者： Wenjing Luan Guanjun Liu Changjun Jiang liang qi Department of Computer Science and Technology Tongji University IEEE Key Laboratory of Embedded System and Service Computing Tongji University

The rapid development of location-based social networks(LBSNs) provides people with an opportunity of better understanding their mobility behavior which enables them to decide their next *** example,it can help travelers to choose where to go next,or recommend salesmen the most potential places to deliver advertisements or sell *** this paper,a method for recommending points of interest(POIs)is proposed based on a collaborative tensor factorization(CTF)***,a generalized objective function is constructed for collaboratively factorizing a tensor with several feature ***,a 3-mode tensor is used to model all users' check-in behaviors,and three feature matrices are extracted to characterize the time distribution,category distribution and POI correlation,***,each user's preference to a POI at a specific time can be estimated by using *** order to further improve the recommendation accuracy,PCTF(Partitionbased CTF) is proposed to fill the missing entries of a tensor after clustering its every *** on a real checkin database show that the proposed method can provide more accurate location recommendation.

关键词： Clustering context feature extraction point of interest(POI) recommendation tensor factorization