• The Journal of the Korea Contents Association
• /
• v.12 no.2
• /
• pp.60-68
• /
• 2012

This paper describes design and implementation of a distributed rendering management system using existing rendering module. Currently, most of 3D commercial software provide modeling, rendering and distributed environment in the whole package. So, the server and client should use the given renderer as is, without the required features. In this paper, we propose a distributed rendering management system that consist of rendering module and distributed rendering client-server. The rendering module can be executed independently and managed by the distributed rendering client. The server requests rendering for each connected client. After the execution, the server gathers rendering result from each client. After gathering, the server provides the rendering result to the user.

• Convergence Security Journal
• /
• v.14 no.5
• /
• pp.37-47
• /
• 2014

A Trojan malicious code is one of largest malicious codes and has been known as a virus that causes damage to a system as itself. However, it has been changed as a type that picks user information out stealthily through a backdoor method, and worms or viruses, which represent a characteristic of the Trojan malicious code, have recently been increased. Although several modeling methods for analyzing the diffusion characteristics of worms have proposed, it allows a macroscopic analysis only and shows limitations in estimating specific viruses and malicious codes. Thus, in this study an ESP model that can estimate future occurrences of Trojan malicious codes using the previous Trojan data is proposed. It is verified that the estimated value obtained using the proposed model is similar to the existing actual frequency in causes of the comparison between the obtained value and the result obtained by the Markov chain.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2002.10a
• /
• pp.25-32
• /
• 2002

Free vibration analysis of radialiy multi-delaminated beams with through-the-width multi-delamination is performed in the present study. The multiple delaminations are considered to be in a radial manner through the thickness from the top surface of the beam. The natural frequencies of the radially multi-delaminated beams are calculated from a new algorithm that is based on the single compound delaminated beam model. That is, beams with radial multi-delaminations are regarded as the sum of a single compound delamlnated beam that is the single sub-delaminated beam from the top surface of global beam. Each result of frequency equation for the single delaminated beam with unknown boundary conditions obtained through continuity conditions Is updated to the next one, With these sequential operations, the final frequency equation of radially multi-delaminated beams is obtained for both ends boundary conditions of global beam. The numerical results carried out for the beams are compared with those of some references to give the reliance on the proposed algorithm and to investigate the effects of the shape, number, size of multi-delaminations on the natural frequency. Compared with the other previously presented model, the proposed algorithm is more flexible in modeling and formulating as the total array size of frequency equation is always four by four. Therefore, the proposed algorithm will reduce the effort of user in formulating the physical model to the numerical model.

• Korean Journal of Computational Design and Engineering
• /
• v.2 no.2
• /
• pp.103-110
• /
• 1997

In the development of large complex assembly, most design changes are from the following reasons.: 1) insufficient consideration of assembling sequence of downstream process. 2) interference and fit-up of related parts. 3) initial design changes which are not completely resolved. In order to reduce the first reason of above, the assembly-centric modeling methodology was proposed in the part (1) of the thesis. In this part (2), a Digital Mock-Up system, which is a tool to build a virtual mock-up in design stage, has been developed in order to prevent the other two reasons. The system can build a virtual assembly in various ways as followings.: 1) assembling parts which are located in user defined envelope. 2) assembling parts with the specified disciplines. 3) assembling parts that are selected in the part list. It can also make an assembly by the combination of above methods. In addition to that, it has the functions to read/write the virtual assembly and to explode parts of the assembly in desired direction. With the virtual assembly, engineers can design interference free parts without making physical mock-up. The system has been implemented with Oracle database management system in CATIA environment.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.16 no.2
• /
• pp.9-18
• /
• 2016

The railroad is one of the most popular means of transport. Howerver, railroad agencies are managing the railroad information and provide its service respectively. That is, because of managing the different information and its type, The user will not receive the correct and integrated information. In this study, We figure out the needs of passengers that they want in railroad service and seek an integrated service plan that railroad passengers can use the railroad information service at a time, at a glance and in one place. Also, we investigate the knowledge-base construction to provide a knowledge map service to railroad passengers.

• Korean Journal of Computational Design and Engineering
• /
• v.7 no.1
• /
• pp.9-17
• /
• 2002

The study is insufficient on process planning of the elliptical deep drawing product. Thus, in this present study, the expert system for elliptical deep drawing products was constructed by using process sequence design. The expert system was developed to be based on the general concept of each entity. The system was developed in this work consists of sixth modules. The first one is a shape recognition module to recognize non-axisymmetric products and to generate Entity_list. The second one is three dimensional (3-D) modeling module to calculate the surface area for non-axisymmetric products. The third one is a blank design module to create suggested blanks of three shapes with the identical surface area. The fourth one is shape design module based on the production rules that play the most important role in an expert system for manufacturing. The production rules are generated and upgraded by inter- viewing field engineers, plastic theory and experiments. The fifth and sixth ones are a graphic module to visualize results of the expert system and a post module to rise user's convenience, respectively. According to constructed the expert system for process sequence design, it was possible to reduce the lead time.

• Journal of Korean Institute of Industrial Engineers
• /
• v.30 no.1
• /
• pp.17-26
• /
• 2004

In this study, the usability evaluation of a menu-structure was performed using spreading activation model with respect to human's memory retrieval. Spreading Activation Model is effectively used to understand the process of information retrieval, so it can be used as a theoretical background for modeling of the process of human's information retrieval. For spreading activation test (SAT), subjects were presented with 67 pairs of menu titles, which consist of a menu title in the high level menu item and a menu title for the next lower level menu item, from Korea University's web site. For performance tests, three scenarios were developed with longer reaction times and ambiguous associations found in the SAT to reflect the existing problems of the website. As a result, the SAT was found to bean effective tool to enhance the website usability because the SAT could bea substitute for the performance test with a high correlation $({\rho}=0.735,\;{\alpha}=0.05)$. After remaining menu titles with slow reaction times and ambiguous associations found in SAT, the website usability was significantly improved with faster reaction times and less ambiguous associations proven with smaller number of web-page visits. Therefore, the SAT could be used as a methodology to design and evaluate the user-centered menu structure related to human's association structure.

• Journal of the Ergonomics Society of Korea
• /
• v.31 no.4
• /
• pp.533-540
• /
• 2012

Objective: This paper targets a framework of a hand gesture based interface design. Background: While a modeling of contact-based interfaces has focused on users' ergonomic interface designs and real-time technologies, an implementation of a contactless interface needs error-free classifications as an essential prior condition. These trends made many research studies concentrate on the designs of feature vectors, learning models and their tests. Even though there have been remarkable advances in this field, the ignorance of ergonomics and users' cognitions result in several problems including a user's uneasy behaviors. Method: In order to incorporate compatibilities considering users' comfortable behaviors and device's classification abilities simultaneously, classification-oriented gestures are extracted using the suggested human-hand model and closed-loop classification procedures. Out of the extracted gestures, the compatibility-oriented gestures are acquired though human's ergonomic and cognitive experiments. Then, the obtained hand gestures are converted into a series of hand behaviors - Handycon - which is mapped into several functions in a mobile device. Results: This Handycon model guarantees users' easy behavior and helps fast understandings as well as the high classification rate. Conclusion and Application: The suggested framework contributes to develop a hand gesture-based contactless interface model considering compatibilities between human and device. The suggested procedures can be applied effectively into other contactless interface designs.

• Geomechanics and Engineering
• /
• v.7 no.1
• /
• pp.37-53
• /
• 2014

A Web-based pile load test (WBPLT) system was developed and implemented in this study. Object-oriented and concept-based software design techniques were adopted to integrate the pile load test database into the system. A total of 673 case histories of pile load test were included in the database. The data consisted of drilled shaft and driven precast concrete pile axial load tests in drained, undrained, and gravel loading conditions as well as pre-analyzed data and back-calculated design parameters. Unified modeling language, a standard software design tool, was utilized to design the WBPLT system architecture with five major concept-based components. These components provide the static structure and dynamic behavior of system message flows in a visualized manner. The open-source Apache Web server is the building block of the WBPLT system, and PHP Web programming language implements the operation of the WBPLT components, particularly the automatic translation of user query into structured query language. A simple search and inexpensive query can be implemented through the Internet browser. The pile load test database is helpful, and data can be easily retrieved and utilized worldwide for research and advanced applications.

• The Journal of Information Systems
• /
• v.21 no.4
• /
• pp.55-79
• /
• 2012

LBS(Location-Based Service) is one of the smartphone application services which has been receiving great attention recently. Various applications of smartphone use LBS to provide innovative services. However, use of LBS raises privacy concerns because the location information of users is constantly exposed. Privacy calculus perspective attempts to understand the characteristics of the user's privacy. It is based on the risk-benefit analysis in the economics' perspective. That is, when the benefit expected through personal information disclosure is higher than risk, we are willing to provide personal information. This research suggested a research model based on the privacy calculus perspective to clarify the effect of information disclosure intention of smartphone LBS application users. Based on the main factors of privacy calculus, perception of privacy risk and privacy benefit, the relationship of the perceived value and the information disclosure intention was empirically analyzed by utilizing structural equation modeling(SEM) methodology. According to the results of the empirical analysis, it was found that all relations have statistically significant explanatory power except the relation between privacy concern and information disclosure intention. This study showed a strong evidence of antecedent factors based on privacy calculus of personal information disclosure in smartphone LBS applications.