• Journal of The Korean Association of Information Education
• /
• v.4 no.2
• /
• pp.179-186
• /
• 2001

The purpose of this study is to design and implement a courseware that makes possible interaction between man and computer in the internet. For this, We select the contents of learning and designe a courseware with text, graphic data. HTML, Java script and Java applet. Some advantages of the courseware are as follows. Interactions between man and computer are possible by giving diverse feedback to input-response in the web. And it is possible to access the courseware regardless of time and space when the network environment of user's computer is suitably equipped. Finally, on operator's part, the revision of the courseware becomes easier and on client's part, the system resources are less required.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.12 no.6
• /
• pp.704-710
• /
• 2009

In this study, a comparison study of flutter analysis for the AGARD 445.6 wing with wind turnnel test data has been conducted in the subsonic, transonic and supersonic flow regions. Nonlinear aeroelastic using FSIPRO3D which is a generalized user-friendly fluid-structure analyses have been conducted for a 3D wing configuration considering shockwave and turbulent viscosity effects. The developed fluid-structure coupled analysis system is applied for aeroelastic computations combining computational structure dynamics(CSD), finite element method(FEM) and computations fluid dynamics(CFD) in the time domain. MSC/NASTRAN is used for the vibration analysis of a wing model, and then the result is applied to the FSIPRO3D module. the results for dynamic aeroelastic response using different turbulent models are presented for several Mach numbers. Calculated flutter boundary are compared with the wind-tunnel experimental and the results show very good agreements.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.5
• /
• pp.214-222
• /
• 2002

Computer simulations are widely used to analyze passenger safety in simulated traffic accidents. ATB, Articulated Total Body, is a computer simulation model developed to predict gross human body response to such dynamic environments as vehicle crashes and pilot ejections. ATB, whose code is open, has high flexibility and application capability that users can easily insert defined modules and functions. ATB is, however, inconvenient as it was coded in FORTRAN and it needs a formated input file. Moreover, it takes much time to make input files and to modify coding errors. This study aims to increase user friendliness by adding a preprocessor program, WINATB(WINdows ATB), to the conventional ATB. WINATB, programmed in Visual C＋＋ and OpenGL, uses ATB IV as a dynamic solver. The preprocessor helps users prepare input files through graphic interface and dialog box. An additional postprocessor makes the graphical presentation of simulated results. In these case of the frontal crash, the rear impact and the side impact, the simulation results obtained by WINATB and MADYMO(MAthematical Dynamic Model) are compared to validate the effectiveness of WINAIB.

• Knowledge Management Research
• /
• v.12 no.5
• /
• pp.25-40
• /
• 2011

Today, Internet users start off using heavily SNS(Social Network Site) such like, Facebook, Twitter. The reason of the growth of using SNS would be closely related to the various services of gaming, playing, entertainment items, sharing information etc., provided by the SNS, technically, the most important one out of the services provided would be behaving of sharing knowledge among people who connected and networked in the site. In sum, we assume that the users may communicate well each other and pay attention to build closely a social network using that kind of activities. However, nevertheless the new trends of communications and sharing knowledge become popular, researchers have just began the research issues in explaining why Internet user rush into SNS and enjoy the time in there. Therefore, we investigate on the reasons of posting knowledge voluntarily in the SNS and how others response to the posted information and actually affected by the behavior. We appled personal relation and social identity theory for this study, which personal relation in SNS may affect on social identity and make them produce knowledge generation. We found that social identity and involvement in SNS is closely related and influence knowledge creation and generation. This empirical study resulted in the importance of social relations in SNS, which leads to a sharing knowledge.

• The Journal of Information Systems
• /
• v.14 no.2
• /
• pp.101-132
• /
• 2005

There is a need for research to identify the integrated, rather than fragmented, factors that determine users' acceptance of Internet shopping. Using the newly revised technology acceptance model (TAM) as a theoretical framework, this study investigates the effect of a set of information systems quality (information quality and system quality) and trust on intention to use Internet showing through perceived ease of use and perceived usefulness. Using structural equation modeling, the results strongly support the utilization of TAM in predicting users' intention to use Internet shopping, and demonstrates the effects of critical external variables on behavior intention through perceived ease of use and perceived usefulness. Systems quality such as response time, accessibility, and usability has significant effects on perceived ease of use of Internet shopping. Futhermore, trust has also a significant effect on perceived usefulness, perceived ease of use, intention to use Internet shopping, and actual usage of Internet shopping. Based on these results, this study suggests managerial implications of new Internet shopping strategies, focusing on the integration of information systems quality and trust in order to achieve sustainable competitive advantage in Internet shopping.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.4
• /
• pp.2149-2170
• /
• 2017

Application-layer Distributed Denial-of-Service (DDoS) attack is one of the leading security problems in the Internet. In recent years, the attack strategies of application-layer DDoS have rapidly developed. This paper introduces a new attack strategy named Path Vulnerabilities-Based (PVB) attack. In this attack strategy, an attacker first analyzes the contents of web pages and subsequently measures the actual response time of each webpage to build a web-resource-weighted-directed graph. The attacker uses a Top M Longest Path algorithm to find M DDoS vulnerable paths that consume considerable resources when sequentially accessing the pages following any of those paths. A detection mechanism for such attack is also proposed and discussed. A finite-state machine is used to model the dynamical processes for the state of the user's session and monitor the PVB attacks. Numerical results based on real-traffic simulations reveal the efficiency of the attack strategy and the detection mechanism.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.17 no.1
• /
• pp.66-71
• /
• 2007

To adapt environment changing high speed and improve rapidly response ability for variation of environment and reduce delay time of decision making inlet agents, the derivation of user's preference and alternative are required. In this paper, we propose an efficient coordination method of multi-agents based on fuzzy decision making with the solution proposed by agents in the view of Pareto optimality. Our method generates the optimal alternative by using weighted value. We compute importance of attributes of winner agent, then can obtain the priorities lot attributes. The result of our method is analyzed that of Yager's method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.170-171
• /
• 2015

At the present time it continues to be the smart device released has also been commercialization device accessories accordingly. Such accessories are getting great response to consumers in the form of an external device to a character commercialization design. However, these products are not useful in the functional aspects of using the external form of the device is concentrated only. This study documents the management app to give the game character acts on the application category grouping the ability to efficiently manage the smart device. Research method is to study the existing product released to find out how it works come from the smart device management side, The device app management features added to the game play will be produced based on them.

• Journal of the Korea Society for Simulation
• /
• v.16 no.2
• /
• pp.1-8
• /
• 2007

Resource management in grid computing environment is essential for integration and interaction among heterogeneous resources. This paper discusses resource management methods of centralized and decentralized broker-based modeling for solving complex problems of resource management and presents design and development of the decentralized broker-based resource management modeling in grid computing environment. This model comprises a global resource broker and a local resource broker, and we derive reduction of communication and functional dispersion of Job management using a local resource broker. The simulation experiment shows the improvement of resource utilization and average response time and proves that this model improves utilization of resources and replies to user requests promptly.

• Journal of the Korea Society for Simulation
• /
• v.22 no.3
• /
• pp.71-79
• /
• 2013

Web server cluster systems are widely used, where a large number of PC level servers are interconnected via network. This paper focuses on forecasting an appropriate number of web servers which can serve four different classes of user requests, simple web page viewing, knowledge query, motion picture viewing and motion picture uploading. Two ways of serving different classes of web service requests are considered, commonly used web servers and service dedicated web servers. Computer simulation experiments are performed in order to find a good way of allocating web servers among different classes of web service requests, maintaining certain levels of resource utilization and response time.