• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1563-1568
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• 2012

Printed electronics is a technology used for forming electronic circuits or devices, and it is used in the manufacture of many products such as RFID tags, solar cells, and flexible display panels with a much lower cost than in the case of semiconductor process technology. Web-guide-type printing such as roll-to-roll printing is a method used to produce printed electronic devices in a large volume. To commercialize such products, highly precise alignment between printed layers is required. In this study, a highly precise alignment system is proposed, and some experimental results are compared with those obtained using a laser surface vibrometer to illustrate the reliability of the proposed system. The robustness of the proposed system to web deformation is also considered experimentally.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.421-423
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• 2003

최근 클러스터 웹 서버의 로드 벨런싱으로서 L4 스위치가 널리 사용되고 있다. 전형적인 L4 스위치는 연결 요구 발생시 back-end 노드들의 부하를 평가하여 적은 부하를 갖고 있는 노드로 요청을 보내는 기능을 수행한다. 그러나 L4 스위치의 부하 분산은 사용자 연결 횟수를 이용해 분산함으로서 사용자의 다양한 컨텐츠 요청에 적절한 부하분산 스케줄링을 적용하고 있지 않다. 본 논문에서는 서버에 전송되는 컨텐츠 요구를 L4 스위치 계층에서 인식하여 부하배분에 사용하는 부하분산 모델을 제시한다.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2004.11a
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• pp.7-7
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• 2004

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1359-1362
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• 2003

The intrusions appears continuously by new unknown attacks exploiting vulnerabilities of systems or components but there are no perfect solutions to protect this unknown attacks. To overcome this problem, in this paper, we have proposed and implemented a Web service intrusion tolerant system that provides continuous Web services to the end users transparently even after the occurrence of an attack against the Web services, and prevents the disclosure of system's configuration data from server Our system has an N+l node architecture which is to minimize the number of redundant server nodes and to tolerate the intrusion effectively, and it also supports diversity in its design. Experimental result obtained on an implemented system show that our system can cope with intrusion such as DoS, file modification, confidentiality compromise of system properly.

• Journal of The Korean Association of Information Education
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• v.15 no.3
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• pp.505-515
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• 2011

Since MEST accredited web-based training institutes for teacher training in December 2000, although there have been growth quantitatively, due to the issues such as difficulty in securing time for training, in communications infrastructure, in interactions between instructors and learners, in fair online evaluation, in contents renewal, in management of learners, web-based training could not reach the potential we expected. This study was conducted to provide the directions for development of teachers' web-based training along with teacher evaluation for professional development. A survey and interview research was conducted to investigate and anaylze the satisfaction research and suggestions, levels of training system use of trainees who had participated in the pilot test of web-based training.

• Steel and Composite Structures
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• v.39 no.3
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• pp.337-352
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• 2021

The study presented experimental and numerical investigation on the seismic performance of steel reinforced concrete (SRC) L-shaped column- reinforced concrete (RC) beam joints. Various parameters described as steel configuration form, axial compressive ratio, loading angle, and the existence of slab were examined through 4 planar joints and 7 spatial joints. The characteristics of the load-displacement response included the bearing capacity, ductility, story drift ratio, energy-dissipating capacity, and stiffness degradation were analyzed. The results showed that shear failure and flexural failure in the beam tip were observed for planar joints and spatial joint, respectively. And RC joint with slab failed with the plastic hinge in the slab and bottom of the beam. The results indicated that hysteretic curves of spatial joints with solid-web steel were plumper than those with hollow-web specimens. The capacity of planar joints was higher than that of space joints, while the opposite was true for energy-dissipation capacity and ductility. The high compression ratio contributed to the increase in capacity and initial stiffness of the joint. The elastic and elastic-plastic story deformation capacity of L-shaped column frame joints satisfied the code requirement. A design formula of joint shear resistance based on the superposition theory and equilibrium plasticity truss model was proposed for engineering application.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.570-578
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• 1999

This paper aims at developing remote control system to control and monitor distributed various devices t through Internet or information communication network. SNJV!P(Simple Network l\ilanagement Protocol) and R Rectifier system with SN:\IP are adoptL'Cl for applied system with network management protocoJ, respectiveJy. F For controJling and monitoring distributed devices in realtime, Java environment software is constructed. Also g general--purpose interface controller between network device and applied device is pro[XJsed. The ProPOSL'Cl c controller is also able to control various devices with communication network remotely.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.28 no.2
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• pp.109-116
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• 2005

In the previous C/S publishing system, the editor or contributor can arbitrarily modify the document created by the author, in which case it is difficult to identify the changes made in the document. Another shortcoming is in that when the document is in need of tracking or editing, the client must have the respective editing system. To solve this problem, the gist of the document must be preserved along with the document itself, and the process of handling the document must be standardized. Publishing on the web ensures a more stable and accurate result in processing documents. The significance of web publishing is made clear, when we consider the importance of information per se and the growing demand for immediate publication in the present day. The need for a simple and straightforward apache-based PDF publishing system, in which HTML and CSS are supported, and a converting engine provides PDF standard security application support, is prominent. This provides a library in which one can directly create a PDF via Windows, Linux, or Unix without having to rely on a client, allowing high-speed PDF creation. The development of a web-accessed PDF converting engine forms the basis for e-transactions, online brochures, electronic B/L, and many other industrial sectors.

• Journal of the Korea Computer Industry Society
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• v.2 no.11
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• pp.1453-1464
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• 2001

Explosive growth of Internet populations results performance degradations of web service. Popular web sites cannot provide proper level of services to many requests, and such poor services cannot give user a satisfaction. Web caching, the remedy of this problem, reduces the amount of network traffic and gives fast response to user. In this paper, we analyze the characteristics of web cache traffics using traces of NLANR(National Laboratory for Applied Network Research) root caches and Education network cache in Seoul National University. Based on this analysis, we suggest a method of prefetching and we discuss the gains of our prefetching. As a result, we find proposed prefetching enhances hit rate up to 3%, response time up to 5%.

• Journal of Korean Society of Steel Construction
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• v.15 no.1
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• pp.17-24
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• 2003

This study aimed to develop experiment-based limiting heights for interior, nonload-bearing, cold-formed steelwall panels sheathed with gypsum board and subjected to uniformly distributed lateral loadings. Th e limiting heightswere evaluated by their strength (for flexure, shear, and web crippling) and deflection. Limiting heights for deflectionlimits of L/360, L/240, and L/120 (where L is the height of the wall) were developed over the range of typical designpressures.