• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.504-516
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• 1997

Recently scientists and engineers are developing a system to get waste heat of low-temperature level with advanced heat pump, which have not been used up to now. As the reason, it is necessary to examine capability of using waste heat which is raised up in the tunnel of subway out of widely distributed low-temperature waste heat in large cities. Therefore we surveyed thermal environment of the tunnel of subway in $S\check{o}my\check{o}n$, downtown of Pusan, from November 1995 to December 1996 and developed a program to predict the thermal environment of subway on the basis of experimental data and the geometries of tunnels. This paper has proved availability of waste heat of subway when the measured results obtained in subway in the winter time and the simulated results of thermal environment prediction program are compared, as well as has reported results of estimating reliability of the simulation program. As the result, the charateristics of thermal environment in the tunnel of subway in $S\check{o}my\check{o}n$ station in the winter time are to be followed; 1) temperature in the tunnel is about $10^{\circ}C$ higher than outside air temperature, 2) temperature change in the tunnel is less than that in the platform so that we may obtain stable heat source, 3) and when the measured results obtained in subway in the winter time and the simulated results of thermal environment prodiction program is compared, both results show similar tendency. Therefore, we confirm estimating reliability of the simulation program.

• Journal of Korean Association for Spatial Structures
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• v.12 no.2
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• pp.45-53
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• 2012

This paper derives Isogeometric analysis and post-processing method of surface that are generated by NURBS basis function for accurate geometric modeling and structure analysis of free-form. By deforming these parameters that are consisted of control points, knots, polynomial, variable geometric models are derived. The basis function that is used to Isogeometric analysis is same to the basis function of NURBS that is used to generate geometric models. For performing isogeometric analysis, h-p-k refinement is performed without changing of original geometry. To visualize the results of isogeometric analysis that control points' displacements, post-processing method that is the interface method between IGES format and Rhinoceros is derived.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.5
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• pp.515-524
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• 2008

The ultimate behavior of high-tension bolted joints with various plate thickness and bolt size is investigated using nonlinear F.E. analysis and experimental study. The relation with sliding load, bolt deformation, and failure modes are presented based on plate thickness and bolt size. Three kinds of the bolt diameter(M20, M22, M24) and five types of the steel plates (l2mm, 16mm, 20mm, 30mm, 40mm) are considered for the ultimate behavior of the bolted joints. The numerical model, constructed by commercial F.E. program, ABAQUS, of ultimate behavior of bolted joints is introduced and verified by experimental results. The force-displacement and force-axial strain relations are measured and compared with the results by 3D finite element analysis.

• The Korean Journal of Rehabilitation Nursing
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• v.5 no.2
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• pp.193-204
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• 2002

This study was a quasi-experimental study of nonequivalent control group pretest- posttest design to investigate the effect of aerobic walking exercise program on the physical & psychological functions of home stayed stroke patients. The data were collected during the period of May 20th to August 15th, 2001. The subjects for this study were 40 hemiplegic stroke patients with the experimental group consisting of 19 patients and the control group being composed of 21 patients. The patients selected for this study were: (a)living in J city who had been diagnosed with stroke and at home after being discharged from the hospital, (b)suffering from stroke for 6 months to 5 years, (c)without recognition disorder with the MMSE-K score above 25, (d)below 2 on the modified Ashworth scale, (e)free from heart and pulmonary disease (f)able to walk beyond 15 minutes for themselves. The aerobic walking exercise program for the experimental group was aerobic exercise and education and supportive care. The aerobic exercise was 8 weeks' period, three times a week, 35 to 50 minutes a day. And the education and supportive care was consisted of one home visiting and 2 times telephoning a week. The data were analysed by $X^2$-test, paired t-test and unpaired t-test and ANCOVA through SAS/PC program. The results of the study were as follows: 1. There was insignificant difference in the gait length experimental and control group. There was significant difference in the gait speed between the two groups. 2. There was significant difference in the dynamic valance between the two groups. 3. There was significant difference in ADL score between the two groups. 4. There was no significant difference in the depression between the two groups. As shown above, the results of 8 weeks' the aerobic walking exercise program for home stayed stroke patients produced positive effects on gait speed, dynamic valance, ADL score. And this program was expected that it was more effective in different intervention period, verified program. Also it was needed follow study.

• Journal of Biosystems Engineering
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• v.10 no.2
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• pp.55-62
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• 1985

박(朴)(1982, 1983, 1984 및 1985)이 개발(開發)한 배합사료공장(配合飼料工場)의 투자비용(投資費用) 및 운전비용(運轉費用)의 수학적모형(數學的模型)을 이용(利用)하여, 배합사료공장(配合飼料工場)의 적정(適正) 시스템의 설계(設計)를 예(例)를 들어 소개하였다. 적정(適正)시스템의 설계(設計)를 위(爲)하여 비선형(非線型) 프로그램의 "Single Objective Programming Problem(단일목적함수(單一目的函數))"와 "'Multiple Objective Decision Making Method(다목적함수(多目的函數))"의 2가지 방법(方法)을 적용(適用)하였다. Single Objective Programming Problem에서는 "Generalized Reduced Gradient(GRG) Method"를 이용(利用)하였고, Multiple Objective Decision Making Method(MODM)에서는 "Interactive Nonlinear Goal Program(INGP)"를 이용(利用)하였으며 그 결과(結果)는 다음의 몇가지로 요약(要約)할 수 있다. 1. 박(朴)이 개발(閒發)한 수학적(數學的) 모형(模型)들은 2 가지 방법(方法) 모두 사료공장(飼料工場)의 최적화(最適化) 설계(設計)에 효과적으로 이용(利用)할 수가 있었다. 2. MODM방법(方法)에 의(依)하여 얻어진 최적(最適)시스템은 Single Objective Program Problem에서 구(求)한 결과(結果)보다 균형(均衡)이 있는 시스템이었으며 장래(將來)의 사료원료(飼料原料), 사료구매시장(飼料購買市場), 기타 다른 조건(條件)들의 변화)에 대(對)해서 보다 탄력(彈力)이 있는 시스템으로 나타났다. 3. 엄밀한 의미(意味)에서 절대적(絶對的)인 최적사료공장(最適飼料工場)이란 있을 수 없으며, 주위의 조건(條件), 원료가격(原料價格), 사료가격(飼料價格), 공장주(工場主)의 취향 및 설계조건등(設計條件等)에 따라 최적(最適) 시스템은 각각(各各) 다르게 나타난다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.9
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• pp.47-54
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• 2008

Cost reduction requires lowering number of power devices used in the converter driving SRM. This is quite feasible in SRM drive systems than in other drive systems. This paper deals with analysis and simulation of a novel two phase SRM. A novel two phase SRM has high performance, self-starling capability, high efficiency, and low manufacturing cost. Additionally, the stator back iron does not experience any flux reversal as the flux is in the same direction whether phase A or B is excited leading to a greater reduction in core losses. The magnetic analysis and design considerations of the novel two phase SRM have been obtained by the finite element analysis (FEM).

• Journal of Digital Convergence
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• v.17 no.10
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• pp.489-496
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• 2019

The purpose of this study was to identify the effects of Pilates' expertise on physical self perception and psychological happiness among adults who participated in the Pilates movement for more than one year. From March 1, 2019 to May 30, 2019, a total of 262 Pilates participants in D and C cities were sampled using the Collective Clustering method. The STSS Ver20.0 statistics program was used to solve the research problem. The study found that first, there were no significant differences in physical self perception and that health had a negative effect on the body's emphasis on the body's neutral and that physical ability had a significant effect on Neutral emphasis on body and Member management. Second, the enjoyment of psychological happiness showed significant differences in An understanding of anatomical knowledge, instructors 'Attitudes, and membership management, while the confidence of psychological happiness showed significant differences in Neutral emphasis on body and Member management. This study shows that the Pilates leader's professionalism has a positive influence on participants and has contributed to presenting basic information regarding various variables.

• Journal of the Korea Convergence Society
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• v.10 no.8
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• pp.153-158
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• 2019

The overall environmental regulations of the industry have been strengthened due to environmental pollution that occurred in modern society. Therefore, R&D of selective reduction catalyst (SCR) is needed to meet these environmental regulations. This paper carried out thermal analysis to develop the pneumatic damper valve (PDV), which is a key component of SCR system. For thermal analysis, verification of material properties was performed first. Verification was performed through the thermal properties test and the thermal tensile test of the specimen, and the results were reinforced with the material properties to enhance the reliability of the thermal analysis.The heat analysis was intended to identify thermal characteristics with PDV in total of three materials (SM400B, SS275, SB410) applied under the conditions of use of PDV, and to confirm the structural stability of the PDV.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.2
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• pp.109-114
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• 2022

Recently, since fine dust has become a serious social problem, air purifiers are in the spotlight as a countermeasure against this. Therefore, in this paper, we conducted R&D on the Smart Autonomous Moving Air Purifier System. The developed Smart Autonomous Moving Air Purifier can improve the limitations of the standard used area of existing air purifiers and perform an air purification function efficiently. In addition, we developed App and Web-based programs together for convenient use of Smart Autonomous Moving Air Purifier. Easily operate three air purification modes (Selection mode, Autonomous highest zone mode, Autonomous instant purification mode) through the App and conveniently monitor statistical values (Recent data, Total data, Warning) anywhere through the Web. And, we showed through test that the proposed Smart Autonomous Moving Air Purifier is more efficient than existing air purifiers.

• Journal of Industrial Convergence
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• v.21 no.8
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• pp.129-136
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• 2023

The purpose of this study was to test the effects of simulation-based delivery nursing practice on proactivity of problem-solving, clinical Performance and team efficacy in nursing college students. This study conducted with a quasi-experimental one group pretest-posttest design. The subjects of the study were those who participated in the pretest-posttest survey among third graders in nursing who took a simulation-based delivery nursing practice class at S university in D city, and finally, data from 78 students who completed the survey were analyzed. Data collection was conducted from August 30, 2022 to October 28, 2022, and data were analyzed using SPSS 27.0 program. The findings suggest that simulation-based delivery nursing practice had a positive effect by significantly increasing on problem-solving proactivity, clinical performance ability, and team efficacy. However, There are limitations in generalizing the study results. therefore based on a sufficient number of samples, the effects should be verified through randomized controlled pre-and post-test and, To determine whether the effects are consistent, it will be necessary to follow up in the long term.