• Journal of Welding and Joining
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• 제21권5호
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• pp.555-560
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• 2003

In automobile industry, it is necessary to reduce the weight from the view point of energy and environmental problems in these days. One of the ways for weight reduction is using adhesive aluminum structures. In this study, ultrasonic signals reflected from the adhesively bonded joint layer are used to evaluate the adhesively bonded joints. FFT is performed to determine bond-layer parameters such as effective thickness and frequency for adhesively bonded joint Al 6061 plates in comparison with the measured and theoretical ratios. And the parameters of ultrasonic wave and the J-integral are investigated to evaluate the adhesively bonded joint strength by DCB specimens.

• The Korean Journal of Pain
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• 제29권1호
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• pp.12-17
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• 2016

Background: The study aimed to determine if ultrasonography of masseter can be used to evaluate the outcome of transcutaneous electrical nerve stimulation (TENS) in subjects with temporomandibular disorders (TMDs) such as myositis and myofascial pain. Methods: Fifteen TMD subjects with myofascial pain/myositis who satisfied the RDC/McNeil criteria were included in the study. All the subjects were administered TENS therapy for a period of 6 days (30 minutes per session). The mouth opening (in millimeters) and severity of pain (visual analogue scale score) and ultrasonographic thickness of the masseter (in millimeters) in the region of trigger/tender areas was assessed in all the subjects both prior and post TENS therapy. A comparison of the pre-treatment and post-treatment values of the VAS score, mouth opening and masseter thickness was done with the help of a t-test. Results: There was a significant reduction in the thickness of masseter muscle (P = 0.028) and VAS scores (P < 0.001) post TENS therapy. There was also a significant improvement in the mouth opening (P = 0.011) post TENS therapy. Conclusions: In the present study, ultrasonography was found to be an effective measuring tool in the assessment of TENS therapy in subjects with myositis and myofascial pain.

• Journal of Welding and Joining
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• 제32권4호
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• pp.46-54
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• 2014

In this study, the effect of bonding temperature and bonding pressure on deformation and tensile properties of diffusion bonded joint of STS304 compact heat exchanger was investigated. The diffusion bonds were prepared at 700, 800 and $900^{\circ}C$ for 30, 60 and 90 min in pressure of 3, 5, and 7 MPa under high vacuum condition. The height deformation of joint decreased and the width deformation of joint increased with increasing bonding pressure at $900^{\circ}C$. The ratio of non-bonded layer and void observed in the joint decreased with increasing bonding temperature and bonding pressure. Three types of the fracture surface were observed after tensile test. The non-bonded layer was observed in diffusion bonded joint preformed at $700^{\circ}C$, the non-bonded layer and void were observed at $800^{\circ}C$. On the other hand, the ductile fracture occurred in diffusion bonded joint preformed at $900^{\circ}C$. Tensile load of joint bonded at $800^{\circ}C$ was proportional to length of bonded layer and tensile load of joint bonded at $900^{\circ}C$ was proportional to minimum width of pattern. The tensile strength of joint was same as base metal.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2010년도 춘계학술발표대회 초록집
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• pp.51-51
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• 2010

Recently just as in the automobile industry, shipbuilders also try to reduce material consumption and weight in order to keep operating costs as low as possible and improve the speed of production. Naturally industry is ever searching for welding techniques offering higher power, higher productivity and a better quality. Therefore it is important to have a details research based on the various welding process applied to steel and other materials, and to have the ability both to counsel interested companies and to evaluate the feasibility of implementation of this process. Submerged-arc welding (SAW) process is usually used about 20% of shipbuilding. Similar to gas metal arc welding(GMAW), SAW involves formation of an arc between a continuously-fed bare wire electrode and the work-piece. The process uses a flux to generate protective gases and slag, and to add alloying elements to the weld pool and a shielding gas is not required. Prior to welding, a thin layer of flux powder is placed on the work-piece surface. The arc moves along the joint line and as it does so, excess flux is recycled via a hopper. Remaining fused slag layers can be easily removed after welding. As the arc is completely covered by the flux layer, heat loss is extremely low. This produces a thermal efficiency as high as 60% (compared with 25% for manual metal arc). SAW process offers many advantages compared to conventional CO2 welding process. The main advantages of SAW are higher welding speed, facility of workers, less deformation and better than bead shape & strength of welded joint because there is no visible arc light, welding is spatter-free, fully-mechanized or automatic process, high travel speed, and depth of penetration and chemical composition of the deposited weld metal. However it is difficult to application of thin plate according to high heat input. So this paper has been focused on application of the field according to SAW process for thin plate in ship-structures. For this purpose, It has been decided to optimized welding condition by experiments, relationship between welding parameters and bead shapes, mechanical test such as tensile and bending. Also finite element(FE) based numerical comparison of thermal history and welding residual stress in A-grade 3.2 thickness steel of SAW been made in this study. From the result of this study, It makes substantial saving of time and manufacturing cost and raises the quality of product.

• 기술혁신학회지
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• 제21권4호
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• pp.1296-1312
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• 2018

문재인정부 들어 제4차 산업혁명의 키워드가 부각되며서 정부의 국가 연구개발예산에 대한 효율성이 주목받기 시작하여 국가과학기술지식정보서비스는 그 역할이 강조되고 있다. 국가과학기술지식정보서비스는 성과, 과제, 연구시설장비, 인력, 사업 등 국가연구개발사업에 대한 정보를 세계 최초로 한곳에서 서비스하는 국가 R&D 정보 지식포털이다. 국가과학기술지식정보서비스는 지난 2005년부터 주관기관으로 한국과학기술정보연구원이 선정되면서부터 서비스를 시작하게 되어 10년 이상 서비스를 지속하고 있다. 이에 본 논문에서는 지난 13년동안 국가과학기술지식정보서비스의 경제적 파급효과를 분석하기 위해 한국은행의 투입 산출표인 산업연관표에 의거하여 산업연관분석을 실시하여, 이론적 차원에서 생산유발효과, 부가가치유발효과, 취업자유발효과와 전방 후방 연쇄효과를 분석한다. 국가과학기술지식정보서비스에 대한 정부의 R&D예산(1,214억원, 2006~2018년)을 투입계수로 설정했을 때, 전문가의 의견을 반영한 생산유발효과는 2,113억원, 부가가치유발효과는 1,008억원, 취업자유발효과는 10억원당 1,822명으로 분석되었다.

• 근관절건강학회지
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• 제25권2호
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• pp.112-121
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• 2018

Purpose: This study was conducted to explore the mediating effect of nutritional status on the relationship between symptom experience and functional status of patients with Chronic Obstructive Pulmonary Disease (COPD). Methods: A total of 141 COPD patients visiting D hospital and I hospital in B city were enrolled in this study. Data were collected from January 2017 to July 2017. Outcome variables were measured by Mini Nutritional Assessment Short-Form (MNA-SF) for nutritional status, The Memorial Symptom Assessment Scale (MSAS) for symptom experience, and The Functional Performance Inventory Short Form (FPI-SF) for functional status. The data were analyzed with descriptive statistics, Pearson's correlation, and path analysis using SPSS/WIN 21.0 and AMOS 25. Results: There was a significant negative correlation between symptom experience and nutritional status (r=-.61, p<.001), a significant negative correlation between symptom experience and functional status (r=-.40, p<.001), and significant positive correlation between nutritional status and functional status (r=.47, p<.001). Symptom experience had indirect effects on functional status through nutritional status. Conclusion: For enhancing functional status in COPD patients, it is necessary to develop nursing intervention programs to enhance symptom management as well as nutritional status.

• 근관절건강학회지
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• 제17권2호
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• pp.173-182
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• 2010

Purpose: The purpose of this study was to examine levels of pain, depression, and adjustment to military life in soldier who experienced low back pain, in order to produce fundamental data for the development of health improvement programs to prevent and manage low back pain in soldiers with low back pain. Methods: Subjects of this study consisted of 317 soldiers who had low back pain. Study instruments were Visual analog scale (VAS), the Center for Epidemiological Studies-Depression Scale (CES-D), and adjustment to military life scale. Collected data were analyzed by the SPSS Win 14.0 program. Results: Mean score of pain was 4.16 points, depression was 8.58 points, and adjustment to military life was 69.15 points. The level of pain was negatively related to adjustment to military life (r=-.241, p<.001) and positively related to depression (r=.262, p<.001). There was a negative relationship between depression and adjustment to military life (r=-.442, p<.001). Conclusion: Soldiers who had low back pain experienced higher levels of pain and depression and lower level of adjustment to military life. Therefore, further study is needed to develop and examine a nursing intervention to manage low back pain for them.

• 대한의용생체공학회:의공학회지
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• 제31권1호
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• pp.74-80
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• 2010

This paper presents the three dimensional gait analysis of the patients with osteoarticular knee allograft reconstruction. The gait analysis has been performed in some medical fields such as orthopedics and neurosurgery for the purpose of the rehabilitation of patients. However, to the author's knowledge, the analysis of gait for the patients with osteoarticular knee allograft reconstruction caused by tumor has not been reported. In this work, In this work, we confirmed the validity of this method by analyzing 50 samples per one gait cycle obtained from each of 3 patients and 3 normal persons. The motion capture was performed using six infrared cameras. The symmetry and stability of the gait patterns are investigated (patients' r=0.39, p<0.05, normal persons' r=0.65, p<0.05) respectively using the correlation coefficients and the standard deviations of the joint angles of the left and right legs. It also would be applied to the comparison analysis where artificial knee joint is transplanted.

• 대한인간공학회지
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• 제34권1호
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• pp.1-10
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• 2015

Objective: The purpose of this paper is to evaluate old and newly designed ammunition boxes from an ergonomic point of view. Background: The ammunition boxes made of wood, which are currently used by the military, have some difficulties such as corrosion and damage of ammunition, environmental pollution, and stock management. Also, damages to the wooden ammunition boxes take place frequently, because soldiers carry them manually. Method: Sixteen participants volunteered to randomly perform lifting, carrying, and side-by-side moving tasks with 4 different old and new boxes, respectively for the ammunitions of 5.56mm, 60mm, 81mm, and 105mm in diameter. The old boxes are made of wood and are currently used in the military, while the new boxes are made of plastics. The joint moments of the elbow, shoulder, back, and knee were measured by using a motion analysis system and force platforms. In addition, an electromyographic system was used to measure the forces of hand and wrist muscles. Results: In most tasks, new boxes caused less joint moments at the elbow and shoulder than old boxes, because the new boxes were lighter and smaller than the old boxes. New boxes also derived less hand and wrist muscle forces due to the provision of fixed hard handles rather than string handles. Conclusion: The ergonomically designed new boxes could reduce the physical stresses of soldiers manually handling ammunitions and be helpful for storage and reuse. Application: This study shows an ergonomic application example for product development and evaluation.

• 한국빅데이터학회지
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• 제6권2호
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• pp.109-124
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• 2021

본 논문에서는 네트워크 분석방법을 활용하여 대학 중심의 산학협력 네트워크의 구조적 특성을 분석하였다. 최근 기술협력 및 공동연구가 성과창출에 긍정적 영향을 미치는 것이 증명됨에 따라, 혁신성과 창출을 위하여 주요 참여주체(대학 및 공공 등)를 중심으로 다양한 형태의 협력활동 추진과 정부의 정책적 지원이 활발하게 진행되고 있다. 하지만 이러한 노력에도 불구하고 성장동력 창출은 다소 미흡한 상황이기에 대학중심의 산학협력 활동강화를 위한 혁신 네트워크 구축 방안 마련이 필요한 시점이다. 이에 본 연구에서는 산학협력 유형(특허, 논문, 공동연구, 기술이전)에 따른 네트워크를 구축하고, QAP상관분석 및 QAP회귀분석을 실시하여 서로 다른 유형의 산학협력 네트워크간 관련성 및 연관성을 통계적 관점에서 분석하였다. 분석결과 공동연구 네트워크는 논문 네트워크와 밀접한 관련이 있으며, 다른 산학협력 네트워크와도 관련성을 가지고 있는 것으로 나타났다. 본 연구는 대학의 새로운 성장동력 창출에 필요한 산학협력 전략수립 및 협력 파트너 발굴 등과 같은 혁신활동을 지원할 수 있을 것이라 기대한다.