• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.279-289
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• 1998

This study deals with the schemes of design, plan and operate maintenance management support systems and with the engineering approach for the solutions to build the maintenance management for the production efficiency. Maintenance Management Information System(MMIS) is the task that must focus on machinery historical data and planned maintenance action. Also the efficient supporting system in a maintenance management is achieved by database which is based on process of machinery's failure history. Designing method of maintenance management information system, maintenance modules are consisted of six factors ; machinery's historical data, lubrication control, check sheet, repair work, availability report, and performance report(control board and detailed reports), and then operators can rapidly utilize data in work place. In the implementation of designed model, program coding has been developed by Visual Basic 3.0. Data insertion, deletion and updating which perform menu screen is implemented by reading data from database. Implementation model based on LAN environment and related data is stored in Microsoft DBMS.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.95-101
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• 2000

To measure springback ratio of thin sheet or plate, winding bend rig is made. It bends a specimen with keeping its curvature constant and measures the bending angles before and after release of bending load. To check the performance of the bend rig, we calculated the bending moment by two ways which are based on simple beam theory. One is that the bending moment is calculated by using the results of bending test, and the other is that the moment is calculated by using the results of tensile tests. The former may entails the effect of the friction between bending pin of the rig and the surface of specimen, but the latter does not contain any effects of the friction since the bending moment is obtained by using tensile tests. Nevertheless, the values of the two bending moment shows the same level of bending moment, which implies that the friction does not influence on the value of springback ratio in spite of the presence of friction within the cope of the test performed in this experiment.

• Transactions of Materials Processing
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• v.5 no.1
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• pp.8-17
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• 1996

In the present study SEAM (Shear Energy Augmented Membrane) elements have been devel-oped. Maintaining the numerical efficiency of conventional membrane elements the effect of out-of-plane deformation (transverse shear deformation) has been incorporated for the purpose of computational stabilization without introducing additional degrees of freedom. Computations are carried out for the deep drawings of square cup to check the validity and the effectiveness of proposed SEAM elements. The computational results are compared with both the existing results. And the effects of process variables like initial sheet thickness punch & die round and clearance are checked

• Transactions of Materials Processing
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• v.9 no.6
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• pp.615-623
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• 2000

The industrial application of hydroforming has a great potential in saying cost and achieving dimensional accuracy in automotive industry presently. The aim of the following article is to investigate the effect of process parameters on hydroformed part. Firstly, we have to investigate the change of mechanical properties for sheet and pipe material according to various radius/thickness ratio(r/t). The change of mechanical properties affects the yield stress more than the total elongation. Increase of yield stress for pipe has a bad influence on formability of hydroforming. Among the roll-forming process, the sizing process didn't change mechanical properties. The process parameters such as the initial pressure, mandrel shape and friction have seriously influenced on formability of hydroforming. Therefore we need to check formability of given material through the FE analysis in the beginning stage of process design and the predicted hydroforming process parameters ate generally a good starting point for the prototype tryout stage. The results of pretending, hydroforming analysis using FE model are good agreement with experimental results.

• 한국IT서비스학회:학술대회논문집
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• 2010.05a
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• pp.452-457
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• 2010

정보시스템 운영은 연속성, 장애에 대한 민감성 등 정보시스템 구축과는 다른 특성을 많이 가지고 있어 감리방법에 있어서도 새로운 방법이 필요하다. 본 논문은 정량화된 운영점검표를 제시함으로써, 운영감리의 객관성과 신뢰성을 확보하고, 감리결과를 정량화하며, 타 운영사례나 과거 운영 상태와의 비교를 가능케 하여, 감리의 품질과 운영감리의 효용성 향상에 기여하고자 하였다. 시스템 운영 정보시스템 감리지침의 기본점검항목을 기준으로 13가지 기본점검항목을 도출하였고, 각 기본점검항목 별로 현재 운영상태가 어떤 수준인지를 평가할 수 있도록 하였으며, 전문가 인터뷰와 현장적용을 통하여 검증하였다.

• Proceedings of the Safety Management and Science Conference
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• 2004.05a
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• pp.33-39
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• 2004

The chemical factory deals with dangerous element and more advance, human-error analyzes and becomes effective research for the country and region, this paper analyes the form of work-miss on human-error according to a safety accident for domestic chemical factory from 1999-2002. It include the present contents and raise issues human knowledge, behavior, judgment, sensibility as an important counterplan that makes the safety solution of work miss. For the point of view of human knowledge, it takes color standard for works to be effective in work place. for behavior, the test has been for risk point of work place and infra worker movement, also the workers performed professional work as classify according to work. for judgement, the valuation sheet is reflected to minimize the human -error and the 3rd supervisor does a cross-check audit beforehand. For sensibility, it is applicable for human relations, information, communication by program to the consciousness and an attitude of worker-supervisor.

• Journal of the Korean Institute of Landscape Architecture
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• v.29 no.1
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• pp.131-139
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• 2001

This paper aims at surveying through case studies the planting possibility on the interval artificial ground between the bank and the core landfill of the first section of works in the SUDOKWON Landfill area landfill area which was completed, followed by the layer-on-layer landfill process involving the latch or sealing layer against emitting landfill gas from the reclaimed waste. The survey results are as follows; 1. The layers of the artificial planting ground on the landfill were established on the basis of top-on-top procedure for a waste layer, a topping soil layer (T=50cm), a gas blocking layer (broken stones T=30cm), a filter layer (non-woven fabric 700g), a sheet protecting soil layer (T=20cm), and a blocking layer (HDPE SHEET 2.0mm), an irrigation layer (SAND T=30cm), a filter layer (non-woven fabric 700g), a sheet protecting soil layer (T=20cm), and a blocking layer (HDPE SHEET 2.0mm), an irrigation layer (SAND T=30cm), a filter layer (non-woven fabric 700g), a planting layer (T=90cm+), a top mound (T=2m). 2. Since no direct damage on the planting layer affected by the landfill gas was detected, planting is found to be still possible and successful except the severely unequal subsidence portion. 3. The mortality rate is discovered different on different trees: Pinus thunbergii (H3.0$\times$W1.0m) 11.25%, Pinus thunbergii (H2.5$\times$W0.8m) 4.73%, Koelreuteira paniculata 8.67%, Hibiscus syriacus 5.68%, Deutzia parviflora 6.50%, Forsythia koreana 8.17%, Rho. yedoense v. poukhanese 32.22%, and Spiraea pru v. symplicifolia 18.89%; although the last two of which are generally considered to have a strong generic growing character, they are subject to be weakened when exposed to the contaminated microclimate of the site like landfill gas. 4. The damage rates, on Pinus thunbergii, Koelreuteria paniculata, Hibiscus syracus, Forsythia koreana, Deutzia parviflora, Rho. yedoense v. poukhanense were shown to decrease to 7.31-17.69% in the second check (June 2000) lower than 5.77-46.92% in the first examination (June 1999), whereas the damage on Spiraea pru v. symplicifolia relatively increased. It is believed that preparatory method of the air pollution, change of temperature, odor by emitting landfill gas, and minute dust from vehicles should be made, and a research on this matter will be conducted in the near future.

• Progress in Medical Physics
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• v.10 no.2
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• pp.95-101
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• 1999

The aims of this report are to classify the incorrect data of patients and the errors of dose and dose distribution observed in QA activities on teleradiotherapy chart, and to analyze their frequency. In our department, radiation physicists check several sheets of patient chart to reduce numeric errors before starting radiation therapy and at least once a week, which include history, port diagram, MU calculation or treatment planning summary and daily treatment sheet. The observed errors are classified as followings. 1) Identity of patient, 2) Omitted or unrecorded history sheet even though not including the item related to dose, 3) Omission of port diagram, or omitted or erroneous data, 4) Erroneous calculation of MU and point dose, and important causes, 5) Loss of summary sheet of treatment planning, and erroneous data of patient in the sheet, 6) Erroneous record of radiation therapy, and errors of daily dose, port setup, MU and accumulated dose in the daily treatment sheet, 7) Errors leading inexact dose or dose distribution, errors not administerd even though its possibility, and simply recorded errors, 8) Omission of sign. Number of errors was counted rather than the number of patients. In radiotherapy chart QA from Jun 17, 1996 to Jul 31, 1999, no error of patient identity had been observed. 431 Errors in 399 patient charts had been observed and there were 405 physical errors, 9 cases of omitted or unrecorded history sheet, and 17 unsigned. There were 23 cases (5.7%) of omitted port diagram, 21 cases (5.2%) of omitted data and 73 cases (18.0 %) of erroneous data in port diagram, 13 cases (3.2 %) treated without MU calculation, 68 cases (16.3 %) of erroneous MU, 8 cases (2.0%) of erroneous point dose, 1 case (0.2 %) of omitted treatment planning summary, 11 cases (2.7%) of erroneous input of patient data, 13 cases (3.2%) of uncorrected record of treatment, 20 cases (4.9%) of discordant daily doses in MU calculation sheet and daily treatment sheet, 33 cases (8.1%) of erroneous setup, 52 cases (12.8%) of MU setting error, 61 cases (15.1%) of erroneous accumulated dose. Cases of error leading inexact dose or dose distribution were 239 (59.0 %), cases of error not administered even though its possibility were 142 (35.1 %), and cases of simply recorded error were 24 (5.9 %). The numeric errors observed in radiotherapy chart ranged over various items. Because errors observed can actually contribute to erroneous dose or dose distribution, or have the possibility to lead such errors, thorough QA activity in physical aspects of radiotherapy charts is required.

• Archives of design research
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• v.14 no.2
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• pp.15-25
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• 2001

With the rapid development of current internet, digital age make human beings intangible. Haptic sense was recognized less important than visual sense and auditory sense, but it plays an important role in determining the quality of products. The goals of this study are embodying haptics using Visual and Auditory preception and designing Visual-Auditory Haptic interface, in the case of actual touching is required but impossible. This study was carried out 3 steps. Firstly, developing the concept of Visual-Auditory Haptic Interface(VAHI) was carried out to make it certain the direction of this study. To get common factors of VAHI, this study researched physical-mechanism of visual, auditory, and haptics senses, and psychological-mechanism. Secondly, identifying factors of V/A haptic sense was analysed by web-evaluation test, to be categorized 11 Emotional Haptic Factors(EHF) and some Design Haptic Factors(DHF). The relation of EHF and DHF was analysed and summarized to VAHI design check sheet. Finally, Applying DHF to VAHI by EHF according to VAHI design check sheet was validated by web-evaluation test, to be resulted 13% increase in reliability and the same in usability. Conclusively, the possibility of embodying haptics using Visual and Auditory preception was resulted to be valid. And this concept can be applied to an interface, such a internet shopping mall and virtual reality, which requires actual touching to perceive haptic information, but it is impossible.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.7
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• pp.2118-2133
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• 1996

A preform is designed by the backward tracing scheme of the rigid-plastic finite element method(FEM) for net-shape shell nosing components without machining after forming. The current process of the shell nosing requires cost-consuming machining to produce final products. Here, the backward tracing scheme of the rigid-plastic FEM, a novel method for preform design of metal forming processes, derives a sound preform for net-shape shell nosing product. The current process is simulated by the rigid-plastic finite element analysis to check the metal flow involved in the forming with a trial preform and its modified preform. The two preforms are found to be inadequate for net-shape shell nosing product. The first application of the back ward tracing scheme derives a preform producing a not-shape shell nosing product. The first application of the backward tracing scheme derives a preform producing a net-shape product numerically, but it is difficult to be formed economically as a preform. Thus an improved preform is designed by the badkward tracing scheme, which is suitable for net-shape manufacturing of the shell nosing components in view of economy of production and forming characteristics of the product. The preform in the current process and a modified preform are confirmed by a series of experiments and the results give the same deformation with the numerical ones. Finally the newly designed preform by the FEM was experimentally proved to be adequate in obtaining net-shape products.