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Contraceptive Experiences of Women of Procreation Age Who Attended Two HealthCenters in the City of Abidjan (Cote d’Ivoire)
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作者 Essis Esme Marie Laure Koffi Kouassi Benjamin +6 位作者 Manouan N’guetta Mathilde Coulibaly-Koné Soltié Aminata Bamba Iba Kpebo Djoukou Olga Denise Konan Loukou Leandres Aka Joseph Ndola Prata 《Health》 CAS 2023年第1期1-19,共19页
Introduction: Maternal mortality, which is estimated at 614 deaths per 100,000 births in C&#244;te d’Ivoire, is associated with a low national contraceptive prevalence rate of 13.9%. In this study, we are interes... Introduction: Maternal mortality, which is estimated at 614 deaths per 100,000 births in C&#244;te d’Ivoire, is associated with a low national contraceptive prevalence rate of 13.9%. In this study, we are interested in the contraceptive experiences of women who attend health centers to estimate their rate of contraceptive use and to assess the factors involved in the use of modern contraceptive methods among women of childbearing age who are exposed to the risk of pregnancy. Method: A descriptive cross-sectional study was conducted from December 2018 to September 2019 among 423 women, who attended two health centers in Abidjan. A bivariate analysis identified factors associated with contraceptive use by these women. A descriptive analysis determined the means for the quantitative variables and the frequencies and percentages of qualitative variables. Interpretation of results was based on significance (α = 5%, 95% CI). Results: Contraceptive prevalence was 37%. There was a significant relationship between contraceptive use and the socio-demographic and reproductive characteristics of women (p Conclusion: Women who were over 35 years age, uneducated, primary school graduates, housewives, unemployed, in the informal sector, Muslims, nulliparous, and lacking information and decision-making power were less likely to use modern contraceptive methods. They are the target population for strategic interventions to improve contraceptive prevalence. 展开更多
关键词 Use Contraceptive Methods WOMEN Health centers Côte d’Ivoire AFRICA
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Crossing Limit Cycles of Planar Piecewise Hamiltonian Systems with Linear Centers Separated by Two Parallel Straight Lines
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作者 Zhou Jin 《Journal of Applied Mathematics and Physics》 2023年第5期1429-1447,共19页
In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of... In this paper, we have studied several classes of planar piecewise Hamiltonian systems with three zones separated by two parallel straight lines. Firstly, we give the maximal number of limit cycles in these classes of systems with a center in two zones and without equilibrium points in the other zone (or with a center in one zone and without equilibrium points in the other zones). In addition, we also give examples to illustrate that it can reach the maximal number. 展开更多
关键词 Limit Cycles Planar Piecewise Hamiltonian Systems Straight Lines centers Equilibrium Points
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Congestion Control Using In-Network Telemetry for Lossless Datacenters
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作者 Jin Wang Dongzhi Yuan +3 位作者 Wangqing Luo Shuying Rao R.Simon Sherratt Jinbin Hu 《Computers, Materials & Continua》 SCIE EI 2023年第4期1195-1212,共18页
In the Ethernet lossless Data Center Networks (DCNs) deployedwith Priority-based Flow Control (PFC), the head-of-line blocking problemis still difficult to prevent due to PFC triggering under burst trafficscenarios ev... In the Ethernet lossless Data Center Networks (DCNs) deployedwith Priority-based Flow Control (PFC), the head-of-line blocking problemis still difficult to prevent due to PFC triggering under burst trafficscenarios even with the existing congestion control solutions. To addressthe head-of-line blocking problem of PFC, we propose a new congestioncontrol mechanism. The key point of Congestion Control Using In-NetworkTelemetry for Lossless Datacenters (ICC) is to use In-Network Telemetry(INT) technology to obtain comprehensive congestion information, which isthen fed back to the sender to adjust the sending rate timely and accurately.It is possible to control congestion in time, converge to the target rate quickly,and maintain a near-zero queue length at the switch when using ICC. Weconducted Network Simulator-3 (NS-3) simulation experiments to test theICC’s performance. When compared to Congestion Control for Large-ScaleRDMA Deployments (DCQCN), TIMELY: RTT-based Congestion Controlfor the Datacenter (TIMELY), and Re-architecting Congestion Managementin Lossless Ethernet (PCN), ICC effectively reduces PFC pause messages andFlow Completion Time (FCT) by 47%, 56%, 34%, and 15.3×, 14.8×, and11.2×, respectively. 展开更多
关键词 Data center lossless networks congestion control head of line blocking in-network telemetry
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Generation of macroscopic entanglement in ensemble systems based on silicon vacancy centers
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作者 Jian-Zhuang Wu Ying Xi +2 位作者 Bo-Ya Li Lian-E Lu Yong-Hong Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期308-315,共8页
Entanglement in macroscopic systems,as a fundamental quantum resource,has been utilized to propel the advancement of quantum technology and probe the boundary between the quantum and classical realms.This study focuse... Entanglement in macroscopic systems,as a fundamental quantum resource,has been utilized to propel the advancement of quantum technology and probe the boundary between the quantum and classical realms.This study focuses on a unique hybrid quantum system comprising of an ensemble of silicon vacancy(SiV)centers coupled to phononic waveguides in diamond via strain interactions.By employing two sets of time-dependent,non-overlapping driving fields,we investigate the generation process and dynamic properties of macroscopic quantum entanglement,providing fresh insights into the behavior of such hybrid quantum systems.Furthermore,it paves the way for new possibilities in utilizing quantum entanglement as an information carrier in quantum information processing and quantum communication. 展开更多
关键词 quantum ENTANGLEMENT SILICON VACANCY centers DIAMOND waveguide
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Dynamic Routing of Multiple QoS-Required Flows in Cloud-Edge Autonomous Multi-Domain Data Center Networks
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作者 Shiyan Zhang Ruohan Xu +3 位作者 Zhangbo Xu Cenhua Yu Yuyang Jiang Yuting Zhao 《Computers, Materials & Continua》 SCIE EI 2024年第2期2287-2308,共22页
The 6th generation mobile networks(6G)network is a kind of multi-network interconnection and multi-scenario coexistence network,where multiple network domains break the original fixed boundaries to form connections an... The 6th generation mobile networks(6G)network is a kind of multi-network interconnection and multi-scenario coexistence network,where multiple network domains break the original fixed boundaries to form connections and convergence.In this paper,with the optimization objective of maximizing network utility while ensuring flows performance-centric weighted fairness,this paper designs a reinforcement learning-based cloud-edge autonomous multi-domain data center network architecture that achieves single-domain autonomy and multi-domain collaboration.Due to the conflict between the utility of different flows,the bandwidth fairness allocation problem for various types of flows is formulated by considering different defined reward functions.Regarding the tradeoff between fairness and utility,this paper deals with the corresponding reward functions for the cases where the flows undergo abrupt changes and smooth changes in the flows.In addition,to accommodate the Quality of Service(QoS)requirements for multiple types of flows,this paper proposes a multi-domain autonomous routing algorithm called LSTM+MADDPG.Introducing a Long Short-Term Memory(LSTM)layer in the actor and critic networks,more information about temporal continuity is added,further enhancing the adaptive ability changes in the dynamic network environment.The LSTM+MADDPG algorithm is compared with the latest reinforcement learning algorithm by conducting experiments on real network topology and traffic traces,and the experimental results show that LSTM+MADDPG improves the delay convergence speed by 14.6%and delays the start moment of packet loss by 18.2%compared with other algorithms. 展开更多
关键词 MULTI-DOMAIN data center networks AUTONOMOUS ROUTING
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In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites
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作者 Peng Zhang Fukuan Li +6 位作者 Mingming He Silu Huo Xueli Zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期126-137,共12页
Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.Howev... Phosphate removal is crucial for eutrophication control and water quality improvement.Electro-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater treatment.However,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and rates.Herein,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally demonstrated.The resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron transfer.The LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing electrodes.The superior phosphate removal performance originates from abundant active centers formed by the coupling of electricfield and capture sites.Besides,the stability and selectivity toward phosphate capture were maintained well even under comprehensive conditions.Moreover,a series of kinetics and isotherms models were employed to validate the electrosorption process.This work demonstrates a deep understanding and promotes a new level of phosphate electrosorption. 展开更多
关键词 Electro-assisted adsorption ELECTROSORPTION Phosphate removal Active centers MOF-derived carbon
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AMAD:Adaptive Mapping Approach for Datacenter Networks,an Energy-Friend Resource Allocation Framework via Repeated Leader Follower Game
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作者 Ahmad Nahar Quttoum Muteb Alshammari 《Computers, Materials & Continua》 SCIE EI 2024年第9期4577-4601,共25页
Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict th... Cloud Datacenter Network(CDN)providers usually have the option to scale their network structures to allow for far more resource capacities,though such scaling options may come with exponential costs that contradict their utility objectives.Yet,besides the cost of the physical assets and network resources,such scaling may also imposemore loads on the electricity power grids to feed the added nodes with the required energy to run and cool,which comes with extra costs too.Thus,those CDNproviders who utilize their resources better can certainly afford their services at lower price-units when compared to others who simply choose the scaling solutions.Resource utilization is a quite challenging process;indeed,clients of CDNs usually tend to exaggerate their true resource requirements when they lease their resources.Service providers are committed to their clients with Service Level Agreements(SLAs).Therefore,any amendment to the resource allocations needs to be approved by the clients first.In this work,we propose deploying a Stackelberg leadership framework to formulate a negotiation game between the cloud service providers and their client tenants.Through this,the providers seek to retrieve those leased unused resources from their clients.Cooperation is not expected from the clients,and they may ask high price units to return their extra resources to the provider’s premises.Hence,to motivate cooperation in such a non-cooperative game,as an extension to theVickery auctions,we developed an incentive-compatible pricingmodel for the returned resources.Moreover,we also proposed building a behavior belief function that shapes the way of negotiation and compensation for each client.Compared to other benchmark models,the assessment results showthat our proposed models provide for timely negotiation schemes,allowing for better resource utilization rates,higher utilities,and grid-friend CDNs. 展开更多
关键词 Data center networks energy-aware resource management resource utilization game-theory mechanisms
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Review of Two Years of Surgical Activities of the General Surgery Department of the Reference Health Center of Commune I of Bamako Mali
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作者 Tounkara Cheickna Cisse Amadou Beydi +5 位作者 Samake Hamidou Diarra Issaka Sanogo Modibo Diarra Bogoba Doumbia Seydou Yena Sadio 《Surgical Science》 2024年第4期195-206,共12页
The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristic... The objectives of this work were to evaluate the surgical activities carried out in the general surgery department of the Reference Health Center of Commune I of Bamako, to describe the sociodemographic characteristics of the operated patients, to determine the main pathologies encountered and to evaluate qualitatively the result of the treatment. In order to improve performance, and the quality of care, and to identify common pathologies in the surgical department, we undertook a retrospective study on surgical activities from January 2009 to December 2010. At the end of this study, out of 474 men and 187 women (equal sex ratio 2.53);we were able to determine the frequency of surgical pathologies. Farmers, housewives and pupils/students were the most represented with 25.9% respectively;20% and 13.3%. The most frequently observed pathologies were wall hernia (44.8%), prostate adenoma (12%) and acute appendicitis (10.5%). The average length of hospitalization was 3.43 days. Infectious complications affected 25 patients (3.8% of cases) and a death rate of 0.45% (i.e. 3 patients). The average cost of care was 53,500 FCFA. Indeed, the reality of surgical practice in health centers was not the same because of the level of skills of practicing surgeons. 展开更多
关键词 Assessment Surgical Activities 2 Years Reference Health Center of Commune I BAMAKO
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Molecular dynamics simulation study of nitrogen vacancy color centers prepared by carbon ion implantation into diamond
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作者 Wei Zhao Zongwei Xu +1 位作者 Pengfei Wang Hanyi Chen 《Nanotechnology and Precision Engineering》 EI CAS CSCD 2024年第3期71-78,共8页
Nitrogen vacancy(NV)color centers in diamond have useful applications in quantum sensing andfluorescent marking.They can be gen-erated experimentally by ion implantation,femtosecond lasers,and chemical vapor deposition... Nitrogen vacancy(NV)color centers in diamond have useful applications in quantum sensing andfluorescent marking.They can be gen-erated experimentally by ion implantation,femtosecond lasers,and chemical vapor deposition.However,there is a lack of studies of the yield of NV color centers at the atomic scale.In the molecular dynamics simulations described in this paper,NV color centers are pre-pared by ion implantation in diamond with pre-doped nitrogen and subsequent annealing.The differences between the yields of NV color centers produced by implantation of carbon(C)and nitrogen(N)ions,respectively,are investigated.It is found that C-ion implantation gives a greater yield of NV color centers and superior location accuracy.The effects of different pre-doping concentrations(400–1500 ppm)and implantation energies(1.0–3.0 keV)on the NV color center yield are analyzed,and it is shown that a pre-doping concentra-tion of 1000 ppm with 2 keV C-ion implantation can produce a 13%yield of NV color centers after 1600 K annealing for 7.4 ns.Finally,a brief comparison of the NV color center identification methods is presented,and it is found that the error rate of an analysis utiliz-ing the identify diamond structure coordination analysis method is reduced by about 7%compared with conventional identification+methods. 展开更多
关键词 NV color center Ion implantation Molecular dynamics(MD)simulation Yield enhancement
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Two stages of subsidence and its formation mechanisms in Mid-Late Triassic Ordos Basin,NW China
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作者 DENG Xiuqin CHU Meijuan +2 位作者 WANG Long CHEN Xiu WANG Yanxin 《Petroleum Exploration and Development》 SCIE 2024年第3期576-588,共13页
Based on a large number of newly added deep well data in recent years,the subsidence of the Ordos Basin in the Mid-Late Triassic is systematically studied,and it is proposed that the Ordos Basin experienced two import... Based on a large number of newly added deep well data in recent years,the subsidence of the Ordos Basin in the Mid-Late Triassic is systematically studied,and it is proposed that the Ordos Basin experienced two important subsidence events during this depositional period.Through contrastive analysis of the two stages of tectonic subsidence,including stratigraphic characteristics,lithology combination,location of catchment area and sedimentary evolution,it is proposed that both of them are responses to the Indosinian Qinling tectonic activity on the edge of the craton basin.The early subsidence occurred in the Chang 10 Member was featured by high amplitude,large debris supply and fast deposition rate,with coarse debris filling and rapid subsidence accompanied by rapid accumulation,resulting in strata thickness increasing from northeast to southwest in wedge-shape.The subsidence center was located in Huanxian–Zhenyuan–Qingyang–Zhengning areas of southwestern basin with the strata thickness of 800–1300 m.The subsidence center deviating from the depocenter developed multiple catchment areas,until then,unified lake basin has not been formed yet.Under the combined action of subsidence and Carnian heavy rainfall event during the deposition period of Chang 7 Member,a large deep-water depression was formed with slow deposition rate,and the subsidence center coincided with the depocenter basically in the Mahuangshan–Huachi–Huangling areas.The deep-water sediments were 120–320 m thick in the subsidence center,characterized by fine grain.There are differences in the mechanism between the two stages of subsidence.The early one was the response to the northward subduction of the MianLüe Ocean and intense depression under compression in Qinling during Mid-Triassic.The later subsidence is controlled by the weak extensional tectonic environment of the post-collision stage during Late Triassic. 展开更多
关键词 Ordos Basin Chang 10 Member Chang 7 Member subsidence center depocenter subsidence mechanism Qinling orogenic belt Indosinian movement
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Typology and Agroecology of Agroecosystems in Vegetation Dynamics in the Ecotones of the Mbam and Inoubou
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作者 Alex Bruno Dong Etchike Lucie Félicité Temgoua +3 位作者 Bertine Tiokeng Marie Caroline Momo Solefack Martin Benoit Ngassoum Pierre Marie Mapongmetsem 《Open Journal of Forestry》 2024年第1期42-66,共25页
Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems ... Agroforestry systems strongly characterize the Cameroonian agrarian landscape. Agroforests are among those structuring the ecotones of Mbam and Inoubou in the Central Cameroon region. Numerous works on agroecosystems of Central and South Cameroon, few have come out contribution of the structure of these traditional systems in the dynamics of the vegetation of these forest-savannah ecotones. The present contribution has the overall objective of demonstrating the structural efficiency of agroforests the dynamics of ecotone vegetation, but also in the conservation of biodiversity. To do this, a participatory analysis was carried out with 56 farmers distributed in the five villages of Makénéné. Botanical inventories supplemented socio-economic household surveys. The data collected was subjected to various analyzes (univariate test, analysis of variance, multivariate test, PCA, CAH). The results reveal that 55.2% of agroforests are less than 15 years old and those with an area greater than 1500 m<sup>2</sup> predominate (33%). They are mainly young with generally small surface areas. The horizontal structure reveals that the largest diameter classes are those of [20 - 30 cm[ and [10 - 20 cm[ with a very low rate of basal area. Agroforests with trees over 10 m high are dominant in five villages of Makénéné. Two types of structural profiles characterize the agroforestry flora of the area, namely intensive pluristratified home gardens on savannah and intensive pluristratified agroforests under forest-savannah transition vegetation. Principal Component Analysis (PCA) and Ascending Hierarchical Clustering (HAC) show three Agroforest Clusters each. The PCA distribution reveals that woody biomass (Y) is strongly correlated with tree diameter (DBH) and significantly with height (Cluster 2). The age (AAG) (Cluster 1) of these agroforests, on the other hand, remains independent of the density (DST) of these trees (Cluster 3). The agroforests in the Nyokon, Carrière and Mocksud villages are the most effective in terms of conserving woody diversity while the agroforests of the Kinding ndé and Nyokon villages are more efficient in the reforestation processes. These results could be considered as effective and quantifiable tools for the certification of numerous cash crops such as cocoa and coffee, which will make it possible to valorize this local knowledge in terms of scientific and in the development of various programs and writing of technical notes. 展开更多
关键词 Agroforests AGROECOSYSTEM Center Cameroon Dynamics AGROECOLOGY TYPOLOGY
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Review of Load Balancing Mechanisms in SDN-Based Data Centers
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作者 Qin Du Xin Cui +1 位作者 Haoyao Tang Xiangxiao Chen 《Journal of Computer and Communications》 2024年第1期49-66,共18页
With the continuous expansion of the data center network scale, changing network requirements, and increasing pressure on network bandwidth, the traditional network architecture can no longer meet people’s needs. The... With the continuous expansion of the data center network scale, changing network requirements, and increasing pressure on network bandwidth, the traditional network architecture can no longer meet people’s needs. The development of software defined networks has brought new opportunities and challenges to future networks. The data and control separation characteristics of SDN improve the performance of the entire network. Researchers have integrated SDN architecture into data centers to improve network resource utilization and performance. This paper first introduces the basic concepts of SDN and data center networks. Then it discusses SDN-based load balancing mechanisms for data centers from different perspectives. Finally, it summarizes and looks forward to the study on SDN-based load balancing mechanisms and its development trend. 展开更多
关键词 Software Defined Network Data Center Load Balancing Traffic Conflicts Traffic Scheduling
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Research on Adaptability Analysis of Environmental Space Demand and Design Optimization of Daycare Centers: Taking Chongqing’s Community F as an Example
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作者 Tijin Gui Minna Yu +1 位作者 Bin Chen Jun Tao 《Journal of World Architecture》 2024年第3期49-56,共8页
Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to de... Currently,there is a lack of research on the detailed environmental spatial design of community daycare centers at the micro level.This study focuses on Community F in Chongqing,using the elderly’s“willingness to demand”as a central aspect.It examines indoor and outdoor environmental space needs at a micro level,considering both functional requirements and spiritual needs based on existing research.The analysis incorporates three adaptive elements:current construction,surrounding environment,and operational management.It explores the feasibility of restructuring spatial layouts,utilizing local resources,and integrating Bayu cultural characteristics.Finally,through design optimization practices,the study proposes three strategies for aging optimization:functional integration and interaction,user-friendly facilities,and emotional connections to place. 展开更多
关键词 Daycare center Environmental space Willingness to demand Design optimization
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Research on the Comprehensive Development Trend of National Fitness Activity Centers
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作者 Liang Tao Jiaqi Wang 《Journal of World Architecture》 2024年第3期84-92,共9页
With the further advancement of the“National Fitness”strategy and the continuous development of the information age,the National Fitness Activity Centers have become more comprehensive.The comprehensiveness is refle... With the further advancement of the“National Fitness”strategy and the continuous development of the information age,the National Fitness Activity Centers have become more comprehensive.The comprehensiveness is reflected in the design of diversified sports functions and spaces.The article serves to explore the comprehensive development trend of National Fitness Activity Centers.Through summarizing and sorting out domestic and foreign cases,the trend of the comprehensive development of National Fitness Activity Centers is predicted at three levels:industry,city,and individual functions. 展开更多
关键词 National fitness National fitness activity center Comprehensive development trend
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How Chinese Financial Centers Integrate into Global Financial Center Networks:An Empirical Study Based on Overseas Expansion of Chinese Financial Service Firms 被引量:17
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作者 PAN Fenghua HE Ziyun +2 位作者 Thomas SIGLER Kirsten MARTINUS Ben DERUDDER 《Chinese Geographical Science》 SCIE CSCD 2018年第2期217-230,共14页
The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has bee... The increasing globalization of the Chinese economy has been enabled by both Chinese financial institutions operating globally as well as international firms operating within China. In geographical terms, this has been organized through a number of strategic cities serving as gateways for the exchange of financial functions, products and practices between China and the global economy. Drawing on location data of financial service firms in China listed on stock exchanges in Shenzhen, Shanghai and Hong Kong, this paper shows that Chinese financial firms are expanding globally and how Chinese financial centers are positioned and connected in the urban networks shaped by these financial service firms. It is found that Hong Kong, China, holds strategic positions in the integration of Chinese cities into global financial center networks, and that establishing a foothold in global financial centers such as New York and London has been a priority for Chinese financial institutions. The increasing capital flows directed by Chinese financial institutionssuggests a shifting global financial geography, with numerous Chinese cities playing increasingly important roles within global financial center networks. 展开更多
关键词 urban networks corporate networks financial service firms global financial centers China
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STUDY ON DEVELOPMENT STRATEGY OF SHIPPING CENTERS AND TRANSPORTATION NETWORKS IN THE YELLOW SEA RIM 被引量:2
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作者 JIN Feng-jun (Institute of Geographic Sciences and Natural Resources Research, Chinese Acad emy of Sciences, Beijing 100101, P.R. China) 《Chinese Geographical Science》 SCIE CSCD 2003年第2期97-103,共7页
It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation networ... It is very important to establish cooperative mechanism to guarantee allmembers to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategiesof shipping centers and transportation network are discussed based on economic globalizationtendency. The results argue that a united transportation network should be built in order to promotethe economic competition of Northeast Asia in the world. As a key component of the economiccooperation, a hierarchical shipping centers network should be established with Hong Kong, Shanghai,Pusan, Kobe, and Tokyo as cores. The authorities of China, Japan, R. 0. Korea and D. P. R. Koreashould make more efforts to build a set of cooperation institutions based on raising thetransportation efficiency. 展开更多
关键词 the yellow sea rim shipping center transportation network hub-and-spoke system
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Phonon Confinement Effect in Two-dimensional Nanocrystallites of Monolayer MoS_2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center 被引量:1
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作者 石薇 张昕 +4 位作者 李晓莉 乔晓粉 吴江滨 张俊 谭平恒 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第5期111-114,共4页
The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, whi... The fundamental momentum conservation requirement q - 0 for the Raman process is relaxed in the nanocrystal- lites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, which is well-known as the phonon confinement effect in NCs. This usually gives a downshift and asymmetric broadening of the Raman peak in various NCs. Recently, the A1 mode of 1L MoS2 NCs is found to exhibit a blue shift and asymmetric broadening toward the high-frequency side [Chem. Soc. Rev. 44 (2015) 2757 and Phys. Rev. B 91 (2015) 195411]. In this work, we carefully check this issue by studying Raman spectra of lL MoS2 NCs prepared by the ion implantation technique in a wide range of ion-implanted dosage. The same confinement coefficient is used for both E' and A'1 modes in 1L MoS2 NCs since the phonon uncertainty in an NC is mainly determined by its domain size. The asymmetrical broadening near the A'1 and E' modes is attributed to the appearance of defect-activated phonons at the zone edge and the intrinsic asymmetrical broadening of the two modes, where the anisotropy of phonon dispersion curves along Г-K and Г- M is also considered. The photoluminescence spectra confirm the formation of small domain size of 1L MoS2 nanocrystallites in the ion-implanted 1L MoS2. This study provides not only an approach to quickly probe phonon dispersion trends of 2D materials away from Г by the Raman scattering of the corresponding NCs, but also a reference to completely understand the confinement effect of different modes in various nanomaterials. 展开更多
关键词 of is NC as Phonon Confinement Effect in two-dimensional Nanocrystallites of Monolayer MoS2 to Probe Phonon Dispersion Trends Away from Brillouin-Zone Center mode in from
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Incidence of Interpersonal Violence among Individuals with Drug Addiction Receiving Compulsory Treatment: A Survey at Two Drug Detention Centers in Hunan, China 被引量:1
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作者 WU Xiao Lin XIE Yi Yun +3 位作者 NING Pei Shan DI Xiao Kang David C.SCHWEBEL HU Guo Qing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第12期883-887,共5页
Drug dependence is a serious global health problem.To assist individuals with drug addiction,China alone has established 678 Compulsory Detoxification Detention Centers (CDDCs) that treat over300,000i ndividuals who... Drug dependence is a serious global health problem.To assist individuals with drug addiction,China alone has established 678 Compulsory Detoxification Detention Centers (CDDCs) that treat over300,000i ndividuals who are required by national law to receive compulsory treatment;because community-based outpatient treatment failed. 展开更多
关键词 A Survey at two Drug Detention centers in Hunan China Incidence of Interpersonal Violence among Individuals with Drug Addiction Receiving Compulsory Treatment
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The Design of Novel High Spin Molecules with Two atoms Spin Centers
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作者 ZHANG Jing-ping YANG Guang-hui +1 位作者 WANG Rong-shun WANG Li-xiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第4期385-387,共3页
关键词 Semiempirical AM1 CI calculations High spin molecules two atoms spin center
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Fine Structure in the Electron Emission Process for Two DX-Like Centers in Sn-Doped AlGaAs
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作者 ZHAN Hua-han KANG Jun-yong HUANG Qi-sheng 《Chinese Physics Letters》 SCIE CAS CSCD 1998年第1期60-61,共2页
Fine structure in the electron emission process for DX(Sn)centers in AlGaAs has been studied with high resolution Laplace defect spectroscopy.The influence of the different local configuration of Al and Ga atoms aroun... Fine structure in the electron emission process for DX(Sn)centers in AlGaAs has been studied with high resolution Laplace defect spectroscopy.The influence of the different local configuration of Al and Ga atoms around the centers on the electron thermal emissions was observed.An experimental evidence for the microscopic structure of two DX-like centers in Sn-doped AlGaAs is provided. 展开更多
关键词 ALGAAS centers DX
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