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Multiscale Characteristics and Connection Mechanisms of Attraction Networks:A Trajectory Data Mining Approach Leveraging Geotagged Data

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Chinese Geographical Science 2024年第3期34卷 533-547页

作者： JIANG Hongqiang WEI ye MEI Lin WANG Zhaobo School of Resource and Environment Engineering Ludong UniversityYantai 264025China School of Geographical Sciences Northeast Normal UniversityChangchun 130024China Changchun University of Finance and Economics Changchun 130122China Jilin Jizhi City Architectural Design Co. LTDChangchun 130012China

Urban tourism is considered a complex system,and multiscale exploration of the organizational patterns of attraction networks has become a topical issue in urban tourism,so exploring the multiscale characteristics and connection mechanisms of attraction networks is important for understanding the linkages between attractions and even the future destination *** paper uses geotagging data to compare the links between attractions in Beijing,China during four different periods:the pre-Olympic period(2004–2007),the Olympic Games and subsequent‘heat period’(2008–2013),the post-Olympic period(2014–2019),and the COVID-19(Corona Virus Disease 2019)pandemic period(2020–2021).The aim is to better understand the evolution and patterns of attraction networks at different scales in Beijing and to provide insights for tourism planning in the *** results show that the macro,meso-,and microscales network characteristics of attraction networks have inherent logical relationships that can explain the commonalities and differences in the development process of tourism *** macroscale attraction network degree Matthew effect is significant in the four different periods and exhibits a morphological monocentric structure,suggesting that new entrants are more likely to be associated with attractions that already have high *** mesoscale links attractions according to the common purpose of tourists,and the results of the community segmentation of the attraction networks in the four different periods suggest that the functional polycentric structure describes their clustering effect,and the weak links between clusters result from attractions bound by incomplete information and distance,and the functional polycentric structure with a generally more efficient network of *** pattern structure at the microscale reveals the topological transformation relationship of the regional collaboration pattern,and the attraction network structure in the four diff

关键词： attraction network travel mobility polycentric structure network motif connectivity mechanism destination management organization(DMO) destination planning Beijing,China

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Clinical observation on 90 cases of primary dysmenorrhea treated by buccal acupuncture therapy:a randomized controlled study

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Journal of Traditional Chinese Medicine 2024年第1期44卷 172-181页

作者： YANG Yi ye Huijun ZHENG Huiling JIN Lihua Department of Obstetrics and Gynecology the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityXinhua Hospital of Zhejiang ProvinceHangzhou 310005China

OBJECTIVE:To explore the short-term and long-term efficacy of buccal acupuncture therapy in the treatment of patients with primary dysmenorrhea(PD).METHODS:A total of 90 patients with PD who were admitted to the Second Affiliated Hospital of Zhejiang University of Traditional Chinese Medicine from January 2020 to December 2021 were included in this study and randomly divided into three groups,including the observation group,the control group,and the placebo group,with 30 patients in each *** in the observation group were treated according to the syndrome types of Traditional Chinese Medicine,those in the control group were treated with Saridon,and those in the placebo group received a *** visual analog scale(VAS)scores of these patients were evaluated at different time points(before treatment,5 min after needle retention,30 min after needle retention,1 h after treatment,2 h after treatment,1 d after treatment,and 2 d after treatment).The Cox Menstrual Symptom Scale(CMSS)scores were assessed before the treatment and after three courses of ***,these two scales were also evaluated during ***,the pain score and adverse reactions of these patients were assessed during ***:After treatment,the VAS and CMSS scores in the observation group decreased significantly(P<0.05)5 and 30 min after needle retention and after ***:Buccal acupuncture therapy is verified to have short-term efficacy in the treatment of *** addition,this therapy has an immediate analgesic effect and long-term efficacy in reducing the severity and frequency of PD.

关键词： buccal acupuncture therapy primary dysmenorrhea pain score randomized controlled trial

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On optimal control at the onset of a new viral outbreak

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Infectious Disease Modelling 2024年第4期9卷 995-1006页

作者： Alexandra Smirnova Xiaojing ye Department of Mathematics&Statistics Georgia State UniversityAtlantaUSA

We propose a versatile model with a flexible choice of control for an early-pandemic outbreak prevention when vaccine/drug is not yet *** that stage,control is often limited to non-medical interventions like social distancing and other behavioral *** the SIR optimal control problem,we show that the running cost of control satisfying mild,practically justified conditions generates an optimal strategy,u(t),t∈[0,T],that is sustainable up until some moment τ∈[0,T).However,for any t∈[τ,T],the function u(t)will decline as t approaches T,which may cause the number of newly infected people to ***,the window from 0 to τ is the time for public health officials to prepare alternative mitigation measures,such as vaccines,testing,antiviral medications,and *** addition to theoretical study,we develop a fast and stable computational method for solving the proposed optimal control *** efficiency of the new method is illustrated with numerical examples of optimal control trajectories for various cost functions and *** results provide a comprehensive demonstration of the effects of control on the epidemic spread and mitigation expenses,which can serve as invaluable references for public health officials.

关键词： Epidemiology Compartmental model Transmission dynamic Optimal control

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Cholesky GAS models for large time-varying covariance matrices

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Journal of Management Science and Engineering 2024年第1期9卷 115-142页

作者： Tingguo Zheng Shiqi ye Department of Statistics and Data Science School of EconomicsXiamen UniversityXiamen361005China Wang Yanan Institute for Studies in Economics Xiamen UniversityXiamen361005China Paula and Gregory Chow Institute for Studies in Economics Xiamen UniversityXiamen361005China

This paper develops a new class of multivariate models for large-dimensional time-varying covariance matrices,called Cholesky generalized autoregressive score(GAS)models,which are based on the Cholesky decomposition of the covariance matrix and assume that the parameters are ***,two types of score-driven updates are considered:one is closer to the GARCH family,and the other is inspired by the stochastic volatility *** demonstrate that the models can be estimated equation-wise and are computationally feasible for high-dimensional ***,we design an equationwise dynamic model averaging or selection algorithm which simultaneously extracts model and parameter uncertainties,equipped with dynamically estimated model *** simulation results illustrate the superiority of the proposed ***,using a sizeable daily return dataset that includes 124 sectors in the Chinese stock market,two empirical studies with a small sample and a full sample are conducted to verify the advantages of our *** full sample analysis by a dynamic correlation network documents significant structural changes in the Chinese stock market before and after COVID-19.

关键词： Cholesky decomposition GAS Dynamic conditional correlations Dynamic model averaging

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Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

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Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun ye Weiheng Chen Zhong-Jie Jiang Zhongqing Jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

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A hybrid memory architecture supporting fine-grained data migration

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Frontiers of Computer Science 2024年第2期18卷 31-41页

作者： ye CHI Jianhui YUE Xiaofei LIAO Haikun LIU Hai JIN National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Department of Computer Science Michigan Technological UniversityMichigan 49931USA

Hybrid memory systems composed of dynamic random access memory(DRAM)and Non-volatile memory(NVM)often exploit page migration technologies to fully take the advantages of different memory *** previous proposals usually migrate data at a granularity of 4 KB pages,and thus waste memory bandwidth and DRAM *** this paper,we propose Mocha,a non-hierarchical architecture that organizes DRAM and NVM in a flat address space physically,but manages them in a cache/memory *** the commercial NVM device-Intel Optane DC Persistent Memory Modules(DCPMM)actually access the physical media at a granularity of 256 bytes(an Optane block),we manage the DRAM cache at the 256-byte size to adapt to this feature of *** design not only enables fine-grained data migration and management for the DRAM cache,but also avoids write amplification for Intel Optane *** also create an Indirect Address Cache(IAC)in Hybrid Memory Controller(HMC)and propose a reverse address mapping table in the DRAM to speed up address translation and cache ***,we exploit a utility-based caching mechanism to filter cold blocks in the NVM,and further improve the efficiency of the DRAM *** implement Mocha in an architectural *** results show that Mocha can improve application performance by 8.2%on average(up to 24.6%),reduce 6.9%energy consumption and 25.9%data migration traffic on average,compared with a typical hybrid memory architecture-HSCC.

关键词： non-volatile memory hybrid memory system data migration fine-grained caching

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Estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy

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International Journal of Mining Science and Technology 2024年第2期34卷 137-148页

作者： Chuangbing Zhou Zuyang ye Chi Yao Xincheng Fan Feng Xiong School of Infrastructure Engineering Nanchang UniversityNanchang 330031China b School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China School of Engineering China University of GeosciencesWuhan 430074China

With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different *** with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture *** to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip *** a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors.

关键词： 3D fracture network Geological entropy Directional entropic scale Anisotropy Hydraulic conductivity

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Deadline-Constrained and Cost-Effective Multi-Workflow Scheduling with Uncertainty in Cloud Control Systems

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Journal of Systems Science & Complexity 2024年第5期37卷 1861-1886页

作者： ye Lingjuan YANG Liwen XIA Yuanqing ZHAN Yufeng ZHAO Xinchao School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Mathematics and Information Networks Beijing University of Posts and TelecommunicationsMinistry of EducationBeijing 100876China School of Automation Nanjing University of Information Science and TechnologyNanjing 210044China School of Automation Beijing Institute of TechnologyBeijing 100081China

In cloud control systems,generating an efficient and economical workflow scheduling strategy for deadline-constrained workflow applications,especially in uncertain multi-workflow dynamic scheduling processes,is a crucial *** optimize the total cost of workflow scheduling,the authors propose a cost-driven heuristic scheduling algorithm F-MWSA which consists of two phases:Fuzzy deadline distribution and fuzzy task *** the fuzzy deadline distribution phase,a new workflow deadline distribution strategy with fuzziness is designed to obtain the sub-deadline constraint of each *** fuzzy task scheduling phase focuses on a cost-effective strategy to assign tasks to cloud resources,reducing multi-workflow scheduling *** evaluations on five real-world workflows demonstrate that the proposed F-MWSA outperforms the baseline policy in terms of total cost,success ratio,resource utilization,and makespan.

关键词： Cloud computing cost-effective deadline constraint multi-workflow scheduling uncertainty

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Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 1-17页

作者： Xiaowei ye Xiaolong ZHANG Yanbo CHEN Yujun WEI Yang DING MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou310015China

During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield *** floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the *** this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel *** mechanism and factors causing upward movement of the tunnel lining are comprehensively *** input variables were selected according to results from analysis of influencing *** prediction performance of two models,PSO-RF and RF(default)were *** Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of *** PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.

关键词： Random forest(RF) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction

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Influence of vibration on the lubrication effect of a splash-lubricated gearbox

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 324-339页

作者： Yi LIU Kailin ZHANG Shuai SHAO Hongxu XIANG Zhijian ye State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

In this study,we investigate the effect of rail vibrations on the lubrication and efficiency of a splash-lubricated gearbox;specifically,the gearbox of a rail-transit vehicle.A high-fidelity 3D numerical model of the gearbox in a moving reference system is described,as well as computational fluid dynamics(CFD)simulations of the gearbox with different vibration *** effects of rotational speed,oil-immersion depth,and different oil-injection volume rates on lubrication and efficiency are *** propose a method of evaluating the internal lubrication condition of a splash-lubricated gearbox and quantitatively compare the effects of different operating parameters on lubrication and ***,our experiment to verify the feasibility of the simulation method is *** results show that with vibration,the churning loss and oil supply for the bearings are significantly higher than those under static *** addition,among different vibrational directions,lateral vibration has the greatest influence on the lubrication condition and efficiency of the *** the studied railway-vehicle gearbox,the best lubrication condition is achieved at a rotational speed of 1600 r/min and an oil-immersion depth of two times the tooth height(***).Rotational speed is the operating parameter that has the most significant effect on the lubrication and efficiencyofthegearbox.

关键词： Comprehensive lubrication evaluation Churning loss Moving reference system Splash lubrication Vibrational excitation Gearbox

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