• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.239-241
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• 2012

The major industrialized nations have continued to develop industrialized construction techniques based on automated production processes in factories, and are applying them to a wide range of building. However, the unit modular construction system has had a shorter history of development and application in Korea compared to advanced countries, and consequently, Korean modular builders have a relatively poor technical capacity. So this study is draw a conclusion on the target of priority improvement for idea creation. It study on the enhancement of the functionality of the tool for assemble of Unit Modular that choose the enhancement of the functionality through the analysis of function on the three-level of functional definition and classification, functional arrangement, functional appraisal.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.153-158
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• 1997

This paper describes a formal safety analysis technique which is demonstrated by performing empirical formal safety analysis with the case study of beamline hutch door Interlock system that is developed by using PLC(Programmable Logic Controller) systems at the Pohang Accelerator Laboratory. In order to perform formal safety analysis, we have built the Z formal specifications representation from user requirement written in ambiguous natural language and target PLC ladder logic, respectively. We have also studied the effective method to express typical PLC timer component by using specific Z formal notation which is supported by temporal history. We present a formal proof technique specifying and verifying that the hazardous states are not introduced into ladder logic in the PLC-based safety critical system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.21-24
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• 2005

In this paper, field application of mass concrete using setting time difference of super retarding agent is reported to reduce hydration heat of concrete placed at newly constructed apartment house in Daejeon. Horizontal placing lift is applied. According to test results,: slump and air content meets the requirement of target values. For compressive strength, it exceeds the nominal strength ordered by the costumer. For temperature history, maximum temperature of center at top section shows $25.6^{\circ}C$, and at bottom section, $35.4^{\circ}C$. According to naked eye's investigation, no hydration heat crack is observed at the surface of concrete.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2001.04a
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• pp.371-378
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• 2001

To enhance seismic performance of a structure ATC-40 and FEMA-273 propose technical strategies such as increasing strength, altering stiffness, and reducing demand by employing base isolation and energy dissipation devices. Specifically the energy dissipation devices directly increase the ability of the structure to dampen earthquake response. However nonlinear dynamic time history analysis of a structure with energy dissipation devices is complicated and time consuming. In this study a simple and straightforward procedure is developed using effective damping ratio to obtain the required amount of viscoelastic dampers in order to meet given performance objectives. Parametric study has been performed for the period of the structure, yield strength, and the stiffness after the first yield. According to the analysis results, earthquake demand and required damping ratio were reduced by installing viscoelastic dampers. The results also show that with the addition of the supplemental damping evaluted by the proposed method the performance of the model structures are well restrained within the target point.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.379-386
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• 2004

The optimal seismic retrofitting of NPP(Nuclear Power Plant) cabinet structures that contained class 1 relays were studies in this paper. During earthquake event, the failure modes of relays are not appeared in form of structural failure, but are appeared in form of contact chatter of relay. Therefore, the retrofitting of cabinet has to be aimed to the reducing of the structural response, such as acceleration. In this study, the optimal characteristic values of dampers were searched by μ-GA (micro-Genetic Algorithm) scheme for several installation patterns. To keep accuracy and efficiency of analysis, the structural models of cabinet were considered as a frame structure. The responses of structure were obtained in form of acceleration response spectra derived from the results of nonlinear time history analysis including damping nonlinearity. The fitness function of the optimum procedure was constructed based on the ratio of maximum spectral value and target GERS (General Equipment Ruggedness Spectra). The results show the good improvements of fitness fur adequate retrofitting pattern. Especially, the improvements of fitness were remarkable when the damping exponents are proper.

• Journal of Chest Surgery
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• v.33 no.7
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• pp.597-600
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• 2000

Pulmonary endomertiosis is a rare disorder with the typical symptom of hemoptysis during menstruation (catamenial hemoptysis). We report a case of a 19-year-old woman, gravida 0, with 3-month history of catamenial hemoptysis which was confirmed with chest computed tomography. She was treated by means of thoracoscopic wedge resection for the right lesion and fuperior segmental resection through the left thoracotomy, successively. Preoperative fluoroscopy-guided hooking for thoracosopic target lwsion was helpful in circumstances with one lung anesthesia. Four months of follow-up after an uneventful discharge revealed out no recurrence of catamenial hemoptysis in symptoms and images.

• Journal of Chest Surgery
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• v.49 no.4
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• pp.321-324
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• 2016

Medical student examination questions of 60 years ago are very rare to find irrespective of medical specialty. Recently, medical student examination questions for thoracic and cardiovascular surgery were found, which were presented between 1957 and 1959 at Seoul National University Medical College. All examination questions were hand-written in six pages by a professor as examiner. Among the six pages, four examination papers were dated and/or the target grade was identified, while the remaining two did not offer any information. These materials are thought to have a valuable historical meaning for the Korean medical community as well as the Department of Thoracic and Cardiovascular Surgery at Seoul National University Hospital.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.205-208
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• 2008

The wind load on building surface is numerically investigated. The geometry of target building is a square cross section and aspect ratio (height (H) to width (d)) is 6. On building surface, the pressure was measured, compared to obtained value from numerical simulation. The numerical simulations were done using URANS with three different turbulence models such as v2-f model, k-${\omega}$model, and k-${\varepsilon}$ model, respectively. The v2-f model showed the best agreement with experimental data in simulating mean pressure coefficients on front, rear and side surface. But unsteady characteristics of pressure history measured on surface is shown a discrepancy between experiment and numerical simulation.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.325-332
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• 2000

The objective of this research work is to develop an autonomous levee-weeding robot. In this paper, pathway control system for the robot is developed and simulated. A prototype autonomous vehicle for levee weeding is also developed and used in the actual test. The results obtained in this research work is summarized as follows; 1) The simulated typical time history of lateral displacements and heading angle of the vehicle in straight run shows that the vehicle tendency is always to achieve the target path from any of its deviated position and heading angle. 2) The test run on an asphalt surface by the prototype crawler-type vehicle is in good agreement with the simulation results.

• MALSORI
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• no.29_30
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• pp.19-42
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• 1995

This paper deals with the current phonological theory named the elementary theory Before manipulating this theory with highest depth, we need to discuss the distinctive feature theory which can be estimated as playing a central role in the standard generative trends. En the element-based phonological theory, the followings might act as tile main traits in differentiating it from other theories: the notion of phonological opposition is regarded as privative one, treating the univalent element as an analysing unit in a phonological process instead of distinctive features, and the nile convention in standard theory is replaced by the element. In chapter 2, a brief history of generative theory is to be described with respect to the merits and demerits of the distinctive feature theory. In chapter 3, After dealing with the current tendency and some prominent aspects of each element theory, a couple of problems thought to be confronted by the distinctive feature theory And the analysing method taken from the element-based theory which may be regarded currently as the alternative to the problems mentioned above will be discussed mainly, The government-based theory introduced by KLV(1985, 1988) may be the main target in discussing the current topic.