0BTimSim: An Efficient Simulator for Wireless Ad-hoc Networks

Hui Xia,Jia Yu,Guo-Dong Wang,Zhen-Kuan Pan 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.4

With the growth of increasingly complex in wireless ad-hoc networks, performance modeling and evaluation play a crucial part in their design process to ensure successful deployment and exploitation in practice. Compared with the actual implementation (testbeds), simulation has become a valuable tool, which allows studying large scale systems that cannot be built practically. However, most simulators currently used for such networks are intended to evaluate individual routing protocol, which should be extracted from the source code and rewritten in accordance with the simulator’s requirements. Thus, in this paper, we design a new wireless ad-hoc network simulator, called Time Step-based Wireless Ad-hoc Network Simulator (TimSim). It is intended to facilitate the migration of simulation code to real devices via providing useful APIs with real device driver. We use a discrete event processor with time step-based feature as the simulating engine, and the data can be transmitted in bit-level. A unique feature of TimSim is its ability to support the simulation of multi-thread programming. Additionally, we import database access to store the simulation information. Extensive experiments have been conducted to evaluate the efficiency of TimSim. Furthermore, a case study on a real system has been presented to illustrate its practicability.

A Novel Ant Colony Optimization Algorithm for QoS-Based Multicast Trusted Routing in Wireless Ad Hoc Networks

Hui Xia,Xiu-qing Lu,Zhen-kuan Pan 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.8

Thin Film Microbatteries Prepared by Pulsed Laser Deposition

Hui xia,Li Lu,S. B. Tang 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.3

There is a growing interest in thin film microbatteries due to miniaturization of electronic devices. The reduction in current and power consumptions of electronic devices makes microbatteries possible as power sources. Hence, if micro-scale thin-film batteries are to be developed, a suitable fabrication processing technique for thin-film cathodes, anodes and electrolytes becomes crucial. Among various thin film deposition techniques, pulsed laser deposition (PLD) is a relatively flexible and powerful technique for preparing high quality and dense thin-film electrodes on a laboratory scale. This paper reviews recent developments in the fabrication of thin-film electrodes by using PLD.

Characterization of Bacteriostatic Sausage Casing: A Composite of Bacterial Cellulose Embedded with ε-Polylysine

Huixia Zhu,Shiru Jia,Hongjiang Yang,Weihua Tang,Zhilei Tan,Yuanyuan Jia 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.6

The feasibility of a novel bacteriostatic sausage casing made of bacterial cellulose (BC) embedded with ε-polylysine (ε-PL) was evaluated. The ε-PL/BC composite was prepared by immersing BC tubes in ε-PL solution and its characteristics were analyzed with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD),and atomic force microscopy (AFM) techniques, respectively. The results suggested that ε-PL molecules were incorporated into the cellulose fiber networks and the ε-PL/BC composite might have a novel unique structure. No significant loss of antimicrobial activity was observed even after autoclaving at 121℃ for 30 min and the oxygen permeability was far below than that of polyethylene (PE) and polyvinyl alcohol (PVA) membrane. Its tensile strength was 51.8 MPa. The ε-PL/BC composite exhibits bacteriostatic and/or bacteriocidal activities against a broad spectrum of Gram-positive and Gram-negative bacteria; as a result, an extended shelf life than controls was observed for sausage packaged with the ε-PL/BC composite.

Performance of Ion Plating TiAlN Coating on YG8

Huixia Zhang,Chonglin Liu,Long Lu,Haipeng Yan,류성기 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.2

Multi-arc ion plating technology and interactive deposition process are adopted to plate TiAlN hard film on the surface of YG8 cemented carbide cutting tools. Study the influences of the coating film parameters to surface appearance with orthogonal experiment method. Observe substrate samples, TiN transition layer and TiAlN coating film under the scanning electron microscope (SEM). Cutting test, friction and wearing test showed that the coated cutting tools are with more wearing resistance. The main wear mechanisms are adhesion, some accompanied by flake layer of disbanding. Coated cutting tools significantly reduces friction coefficient. By experimental design, the best process parameters are deposition temperature 100oC, substrate negative bias voltage 250 V, nitrogen partial pressure 0.6 Pa.

On the Locality Modeling of Web Access Stream

Huixia Wang,Yao Yao 보안공학연구지원센터 2014 International Journal of Grid and Distributed Comp Vol.7 No.5

Using mathematical method to model Web workload locality characteristics is established based on the study of entropy and coefficient of variation. Experiments show that these metrics can depict locality characteristics more properly and are much easier to use.

Research on Meshfree Method for Analyzing Seal Behavior of a T-DGS

Huixia Zhang,Weiqing Huang,Yan Wang,Long Lu,류성기 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.4

This paper presents a novel approach through the Meshfree weak-strong method based on radial basis function, to calculate the distribution of dimensionless pressure of T-groove dry gas seal (T-DGS). In order to avoid a singularity and improve the accuracy of results, linear polynomials were added into the radial basis interpolation and described gas film stress of T-DGS in the form of explicit function characterization. The opening force, gas film stiffness and leakage rate were obtained by the Matlab calculation program. Compared with the related literature, the error was less than 5%, indicating the feasibility of the simulation. The systematic simulation was used to analyze the multi-parameters for T-DGS under different working conditions. The results revealed the influence mechanism of the pressure, rotational speed, groove depth, film thickness and groove number on the sealing performance. By means of the 3D distribution diagrams of the sealing dynamic and static pressure, we found that dry gas seal could well adapt to high speed condition and the formation mechanism of dry gas seal opening force.

The Research of Platform Vibration Characteristics based on Numerical Wave Simulation

Zhang, Huixia,Huang, Weiqing,Yang, Quan,Lu, Long,Tang, Wenxian,Lyu, Sungki 한국정밀공학회 2014 International Journal of Precision Engineering and Vol.15 No.3

Fluent and ANSYS Workbench platfrom are applicated to make a research on the time course of jack-up drilling platform under extreme wave load. Track free surface with UDF macro and VOF method. Establish numerical wave flume with the function of wave generation and wave absorbing to simulate limit value linear wave and third order Stokes wave. Flow field physical model of jack-up drilling platfrom and trussed legs are established to study the time course of wave load under wave impact. Analyze wave pressure and speed distribution of the field around trussed legs and platform and calculate the stress distribution of platform structure under wave load. The calculating results of wave load will provide a basis for evaluating the influence of wave load to drilling platfrom and designing drilling platfrom rationally.

中国公司法律形态结构改革的走向

胡慧霞(HU HUIXIA) 원광대학교 법학연구소 2019 圓光法學 Vol.35 No.4

受所有制意识形态以及经济体制改革特殊历史原因的深刻影响,中国形成了经济和法律双轨并行的企业分类模式和与此相对应的企业立法体系。虽然这些法律法规在中国的经济发展过程中发挥了不可替代的作用,但是随着社会主义市场经济的发展以及企业国际竞争的加剧,双轨制的企业立法体系所具有的种种弊端不断暴露。从企业形态的发展历史以及企业的本质来看,独资企业、合伙企业实质上类似于无限公司、两合公司,具有可替代性。因此,公司法修改可以将个体工商户、个人独资企业、合伙企业根据股东承担责任的不同改造为无限公司、两合公司,并在此基础上重构中国企业立法体系,将不同组织形式的企业统一到公司法调整。企业法律形态的一体化,提高企业国际竞争力,有利于实现公司法现代化。 Deeply influenced by the ideology of ownership and the special historical reasons of the reform of economic system, China has formed a dual-track enterprise classification model of economy and law and the corresponding enterprise legislation system. Although these laws and regulations have played an irreplaceable role in China s economic development, with the development of the Socialist market economy and the intensification of International Competition Among Enterprises, the shortcomings of the dual-track system of enterprise legislation are constantly exposed. From the development history of the enterprise form and the essence of the enterprise, the sole proprietorship and the partnership are essentially similar to the General Partnership and the Binghe Company in the Korean Commercial Code and the Japanese Company Code. Therefore, in the future, China can take the existing company law as a blueprint and transform individual businesses, sole proprietorships and partnerships into general partnership and joint ventures according to the different responsibilities of shareholders, on this basis, the enterprise legislation system of China is reconstructed, and the enterprises with different forms of organization are unified into the company law. The integration of the legal form of the enterprise is conducive to improving the international competitiveness of the enterprise and realizing the modernization of the company law.

SNS 이용동기의 선택 선호도에 관한 한·중 비교 연구

왕혜하(Wang, Huixia),신호균(Shin, Ho-Kyun) 한국의사결정학회 2014 의사결정학연구 Vol.22 No.2

최근 참여, 공유, 개방을 핵심 키워드로 삼는 web 2.0은 정보기술의 발전과 미디어 환경의 변화로 인하여 페이스북, 트위터 등 다양한 소셜 네트워크 서비스(SNS)가 등장하였다. 이러한 현상은 스마트 기기의 보급과 함께 다양한 방식의 실시간 커뮤니케이션 활동을 가능케 했을 뿐만 아니라 단순한 여가시간 활용을 넘어 관계형성, 정보추구, 일상생활기록을 통해 개인의 다양한 개성을 표현하는 수준으로 확장되고 있다. 이에 본 연구는 한·중 대학생들의 SNS 이용동기에 따른 선호도는 어떠한 차이점과 공통점이 있는지를 4가지 동기인 심리적, 사회적, 정보적, 유희적 동기를 중심으로 고찰하였다. 구체적으로 AHP(Analytic Hierarchy Process)를 이용해 각 국가의 대표적인 10개 SNS를 선정하여 한·중 대학생들의 SNS 선호도를 분석하였다. 연구의 결과는 다음과 같다. 첫째, 한국 대학생들의 SNS 이용동기는 사회적 동기(40.0%)가 가장 높았고, 중국 대학생들은 유희적 동기(33.6%)가 가장 높게 나타났다. 한편, 한·중 대학생들은 모두 SNS를 사용함에 있어 심리적 동기가 가장 낮은 선호 요인으로 나타났다. 둘째, 한·중 대학생들의 SNS 사용동기에 가중치를 반영하여 SNS 선택 선호도를 분석하였다. 그 결과, 한국 대학생들은 페이스북(24.0%)을, 중국 대학생들은 시나웨이보(24.3%)를 가장 많이 쓰는 SNS로 나타났다. 마지막으로, 한국과 중국의 대표적인 10개 SNS 민감도를 분석하여 향후 발전 추이를 예측하였다. 본 연구는 SNS 동기요인을 비교하는데 문화적 이질성을 한계로 들 수 있다. Recently, Web 2.0 represented by key words such as participation, sharing, and openness has vastly changed media-related environment and this change has resulted in the appearance of different Social Network Services(SNS) such as Facebook, Twitter and so on. This phenomenon not only enables people to communicate be engaged with different types of real-time communication activities, but also expands the activities to an extent of expressing one’s different characteristics through building relationships, seeking information, streaming life and a lot more. This study examined if the degree of preference based on use motives has differences and similarities on university students between Korea and China, focusing on 4 types of motives of psychological, social, informative, playful motives. Specifically, the study selected 10 representative SNS services of each country and analyzed SNS preferences of each student and analyzed the students’ in both countries utilizing AHP(Analytic Hierarchy Process). The results of the study are as follow. First, for Korean students, social motive has the most significant impact(40.0%) on SNS use motives. For Chinese students, playful motive has the highest impact(33.6%). On the other hand, both Korean and Chinese students shown psychological motive as the lowest significant factor. Second, this study analyzed SNS use motives reflecting weights of factors. The result shows that Facebook is the most frequently used SNS(24.0%) in Korea. It also shows that the most frequently used SNS in China is Sina Weibo(24.3%). Finally, the study predicted the future development tendencies of the representative SNS by using sensitivity analysis. The implications of these findings, limitations, and future research directions wee also discussed.