Medical Reform and Enjoyment of Health for Everyone

Tong, Xing 전남대학교 지역개발연구소 1999 지역개발연구 Vol.31 No.1

Physical Layer Security in Wireless Ad Hoc Networks Under A Hybrid Full-/Half-Duplex Receiver Deployment Strategy

Tong-Xing Zheng,Hui-Ming Wang,Jinhong Yuan,Zhu Han,Moon Ho Lee INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS 2017 IEEE Transactions on Wireless Communications Vol. No.

<P>This paper studies physical layer security in a wireless ad hoc network with numerous legitimate transmitter-receiver pairs and eavesdroppers. A hybrid full-duplex (FD)/half-duplex receiver deployment strategy is proposed to secure legitimate transmissions, by letting a fraction of legitimate receivers work in the FD mode sending jamming signals to confuse eavesdroppers upon their information receptions, and letting the other receivers work in the half-duplex mode just receiving their desired signals. The objective of this paper is to choose properly the fraction of FD receivers for achieving the optimal network security performance. Both accurate expressions and tractable approximations for the connection outage probability and the secrecy outage probability of an arbitrary legitimate link are derived, based on which the area secure link number, network-wide secrecy throughput, and network-wide secrecy energy efficiency are optimized, respectively. Various insights into the optimal fraction are further developed, and its closed-form expressions are also derived under perfect self-interference cancellation or in a dense network. It is concluded that the fraction of FD receivers triggers a non-trivial tradeoff between reliability and secrecy, and the proposed strategy can significantly enhance the network security performance.</P>

Multi-Antenna Transmission With Artificial Noise Against Randomly Distributed Eavesdroppers

Tong-Xing Zheng,Hui-Ming Wang,Jinhong Yuan,Towsley, Don,Moon Ho Lee Institute of Electrical and Electronics Engineers 2015 IEEE Transactions on Communications Vol. No.

<P>In this paper, we study the secure multi-antenna transmission with artificial noise (AN) under slow fading channels coexisting with randomly located eavesdroppers. We provide a comprehensive secrecy performance analysis and system design/optimization under a stochastic geometry framework. Specifically, we first evaluate the secrecy outage performance, and derive a closed-form expression for the optimal power allocation ratio of the information signal power to the total transmit power that minimizes the secrecy outage probability (SOP). Subject to a SOP constraint, we then propose a dynamic parameter transmission scheme (DPTS) and a static parameter transmission scheme (SPTS) to maximize secrecy throughput, and provide explicit solutions on the optimal transmission parameters, including the wiretap code rates, the on-off transmission threshold and the power allocation ratio. Our results give new insight into secure transmission designs. For example, secrecy rate is a concave function of the power allocation ratio in DPTS, and AN plays a significant role under SOP constraints and in dense eavesdropper scenarios. In SPTS, transmission probability is a concave function of the power allocation ratio, and secrecy throughput is a quasi-concave function of the secrecy rate. Numerical results are demonstrated to validate our theoretical analysis.</P>

The Upgrading of the Functions of Chinese Urban Community Services : Meeting the Challenge of the Economic Globalization

Tong, Xing 전남대학교 지역개발연구소 2001 지역개발연구 Vol.33 No.1

The essay qoltes the concept of safety value as the joint of Economic globalization and community service. Economic globalization has brought many dynamic factors to all countries, especially those developing countries, which brought those factors into communities with people's sense of belonging and identity, is the safety valve for the stability and development of the society. The article suggests that we should promote the function of community services, namely the services of oldster caretaking, employment, building the lifelong learning community and conforming subculture; affording the information for people and enterprises. At the same time, we initiatc volunteer and non-profit organizations Globalization has become popular since the mid 1980's, which reflects the general characteristics and the main trends of the current world. First of all, globalization means economically. Globalization of nowadays shows itself a comprehensive and all-dimensional mixture from material to spirit, but above all, it's still an economic phenomenon, an economic process and an economic concept. Economic globalization means that the world has became smaller and networked because of the progress of science and technology and the development of information, the relation between people and between nations are closer and interdependent. Globalization is powerful, however, the power of localization that counter it also seems mighty. The particularity and independence of each country, ethic group and region are developing vertically, regional autonomies, community movements and non-governmental organizations and becoming new political hotspots. The common standards of every country have changed into $quot;global thinking and local operating$quot;.

Multi-Antenna Transmission in Downlink Heterogeneous Cellular Networks Under A Threshold-Based Mobile Association Policy

Zheng, Tong-Xing,Wang, Hui-Ming,Lee, Moon Ho Institute of Electrical and Electronics Engineers 2017 IEEE Transactions on Communications Vol. No.

<P>With the recent emergence of 5G era, heterogeneous cellular networks (HCNs) have invoked a popular research interest. In this paper, we provide a comprehensive analysis for multi-antenna transmissions in a multi-tier downlink HCN. We first propose a reliability-oriented threshold-based mobile association policy, where each user connects to the strongest base station from which this user can obtain the largest <I>truncated long-term received power</I>. Under our mobile association policy, we derive analytical expressions for the exact outage probability of an arbitrary randomly located user, along with computationally convenient lower and upper bounds. Asymptotic analysis on the outage probability shows that introducing a large access threshold into mobile association significantly decreases the outage probability. We further investigate the spectrum efficiency and the energy efficiency of the HCN. Our theoretic analysis and numerical validations show that both the spectrum and energy efficiencies can be improved by properly choosing the access threshold.</P>

Safeguarding Decentralized Wireless Networks Using Full-Duplex Jamming Receivers

Zheng, Tong-Xing,Wang, Hui-Ming,Yang, Qian,Lee, Moon Ho IEEE 2017 IEEE Transactions on Wireless Communications Vol.16 No.1

<P>In this paper, we study the benefits of full-duplex (FD) receiver jamming in enhancing the physical-layer security of a two-tier decentralized wireless network with each tier deployed with a large number of pairs of a single-antenna transmitter and a multi-antenna receiver. In the underlying tier, the transmitter sends unclassified information and the receiver works in the half-duplex (HD) mode receiving the desired signal. In the overlaid tier, the transmitter delivers confidential information in the presence of randomly located eavesdroppers, and the receiver works in the FD mode radiating jamming signals to confuse eavesdroppers and receiving the desired signal simultaneously. We provide a comprehensive performance analysis and network design under a stochastic geometry framework. Specifically, we consider the scenarios where each FD receiver uses single-and multi-antenna jamming, and analyze the connection probability and the secrecy outage probability of a typical FD receiver by deriving accurate expressions and more tractable approximations for the two probabilities. We also determine the optimal deployment density of the FD-mode tier to maximize the network-wide secrecy throughput subject to constraints including the given dual probabilities and the network-wide throughput of the HD-mode tier. Numerical results are demonstrated to verify our theoretical findings, and show that the network-wide secrecy throughput is significantly improved by properly deploying the FD-mode tier.</P>

20대 직장인 운동 동기에 미치는 영향 요인 분석

동갈흠(Tong Ke-Xing) 한국디자인학회 2016 한국디자인학회 학술발표대회 논문집 Vol.2016 No.10

Refining and Validating a Two-stage and Web-based Cancer Risk Assessment Tool for Village Doctors in China

Shen, Xing-Rong,Chai, Jing,Feng, Rui,Liu, Tong-Zhu,Tong, Gui-Xian,Cheng, Jing,Li, Kai-Chun,Xie, Shao-Yu,Shi, Yong,Wang, De-Bin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.24

The big gap between efficacy of population level prevention and expectations due to heterogeneity and complexity of cancer etiologic factors calls for selective yet personalized interventions based on effective risk assessment. This paper documents our research protocol aimed at refining and validating a two-stage and web-based cancer risk assessment tool, from a tentative one in use by an ongoing project, capable of identifying individuals at elevated risk for one or more types of the 80% leading cancers in rural China with adequate sensitivity and specificity and featuring low cost, easy application and cultural and technical sensitivity for farmers and village doctors. The protocol adopted a modified population-based case control design using 72, 000 non-patients as controls, 2, 200 cancer patients as cases, and another 600 patients as cases for external validation. Factors taken into account comprised 8 domains including diet and nutrition, risk behaviors, family history, precancerous diseases, related medical procedures, exposure to environment hazards, mood and feelings, physical activities and anthropologic and biologic factors. Modeling stresses explored various methodologies like empirical analysis, logistic regression, neuro-network analysis, decision theory and both internal and external validation using concordance statistics, predictive values, etc..

Study of Ablation of Arc Contacts and Dynamic Contact Resistance in High Current Breaker

Licheng Xing,Xiaodong Zhang,Qingbin Tong,Gaoqi Xing 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.3

The fault of power circuit breaker (PCB) can lead very serious problems, especially in high voltage–power grid. The structure of contacts may be composed of main contacts and arc contacts, and this structure can avoid ablation of main contacts efciently. It is necessary to study the eroded state of the arc contacts and the dynamic contact resistance of arc contacts to estimate the operating state of the PCB. The wear of contacts contains arc ablation and mechanical wear through the characteristics of contacts. The arc ablation is caused by the high temperature of the arc and the mechanical wear is caused by the mechanical friction of static and movable contacts. Some experiments have been done under diferent size of contacts and diferent current through them. The results show that the mechanical wear increases, sometimes heavier, with the increase of the size of fxed contacts and the decrease of the size of movable ones because the force between fxed and movable contacts becomes larger. The results also show that the ablation of arc contacts increases with the increase of current, especially when the current is up to 20 kA. With the high temperature of arc reaching the hardness point of copper, the arc ablation and mechanical erosion are increasing obviously since the contacts become soft and easy to wear. Another result of the study shows it is important to choose the material of contacts and the force between movable and fxed contacts. The harder and less resistance the material of contacts, the better the operating situation. To monitor the operating situation of the breaker, the dynamic contact resistance was measured 25 times. As a result, the dynamic contact resistance is sensitive to the current and increasing with the increase of continuous experiment time because of the increasing of metal ions. Furthermore, if the SF6 in the PCB is changes, the dynamic contact resistance would be changed. The dynamic contact resistance in this experiment varies substantially within the range of 80–250 μΩ at the current of 20 kA.

제 10 차 한 중 일 국제 학술대회 ( 1999 . 10 . 15 ) / 삶의 질 향상을 위한 21 세기의 과제 : 제 2 부 삶의 질과 의료 서비스 ; 모든 사람의 건강향유를 위한 의료계획

동성(Tong Xing) 전남대학교 지역개발연구소 1999 제 10 차 한 중 일 국제 학술대회 Vol.- No.-