• 한국기계가공학회지
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• 제17권6호
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• pp.130-135
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• 2018

Currently the automobile market is developing eco-friendly vehicles in order to cope with fuel efficiency regulations. Many studies have been conducted to improve travel performance and fuel economy of the environment-friendly vehicles, and vehicle manufacturers study how to manufacture light-weight vehicles for improving fuel economy for both existing vehicles and environment-friendly vehicles. Exemplary light-weight vehicle technologies include optimal design of vehicle body structure which is a light-weight vehicle method by changing component shapes or layout to optimize the vehicle body structure and the new process technology for using new light-weight and very strong materials Various studies.

• International Journal of Heart Failure
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• 제6권1호
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• pp.22-27
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• 2024

Body fluid monitoring and management are essential to control dyspnea and prevent re-hospitalization in patients with chronic heart failure (HF). There are several methods to estimate and monitor patient's volume status, such as symptoms, signs, body weight, and implantable devices. However, these methods might be difficult to use for reasons that are slow to reflect body water change, inaccurate in specific patients' condition, or invasive. Bioelectrical impedance analysis (BIA) is a novel method for body water monitoring in patients with HF, and the value in prognosis has been proven in previous studies. We aim to determine the efficacy and safety of home BIA body water monitoring-guided HF treatment in patients with chronic HF. This multi-center, open-label, randomized control trial will enroll patients with HF who are taking loop diuretics. The home BIA group patients will be monitored for body water using a home BIA device and receive messages regarding their edema status and direction of additional diuretics usage or behavioral changes through the linked application system once weekly. The control group patients will receive the usual HF management. The primary endpoint is the change in N-terminal prohormone of brain natriuretic peptide levels from baseline after 12 weeks. This trial will provide crucial evidence for patient management with a novel home BIA body water monitoring system in patients with HF.

• 한국산학기술학회논문지
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• 제16권10호
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• pp.7071-7077
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• 2015

최근 스마트폰, 태블릿 PC 및 전자기기 등의 사용이 증가함에 따라 커버글라스의 수요가 증가하고 있는 추세이다. 모바일 기기의 디스플레이가 대형화되면서 접촉이나 낙하 등과 같이 외부에서 힘을 받게 되는 환경에서 높은 강도를 유지하는 것이 요구되고 있다. 커버글라스 제작 공정에서 연마공정은 커버글라스의 표면거칠기 및 충분한 강도를 제공하는 중요한 공정이다. 기존 연삭 숫돌에 의한 가공방법은 커버글라스 가공표면에 스크레치, 칩핑, 노칭 및 마이크로 크랙 등의 가공 문제점이 발생한다. 따라서 본 연구에서는 모바일 커버글라스의 연마를 위해 연마필름을 이용한 폴리싱 시스템을 개발하였다. 구조적 안정성을 평가하기 위해 연마 필름 폴리싱 시스템에 대한 유한요소모델을 생성하였고 다물체 동역학 해석을 수행하였다. 연마 필름 폴리싱 시스템에 대한 응력 및 변위 해석을 통해 특성을 분석하였고 레이저 변위 센서를 이용해 제작된 시스템에 대한 변위를 측정하여 구조적 안정성에 대해 확인하였다.

• 대한조선학회논문집
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• 제53권2호
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• pp.135-143
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• 2016

In this study, an embedded system composed of equipment setting, block importing, scenario setting and output reporting is developed in multi-body dynamics program, ADAMS, for conducting dynamic structural analysis of block lifting process. First, equipment used for block lifting process is set in the simulation environment and the shapes and functions of two lifting beams, and six block loaders are provided as the equipment. Second, the modal analysis result of the lifting block is imported from the static structural analysis system, NASTRAN. Third, the lifting scenarios, such as hoisting, waiting, trolley moving, and wire connecting, are set in the system. Finally, output results in the forms of plots, texts and tables, are reported after the dynamic structural analysis. The test examples conducted in a shipyard are applied into the developed system in various condition and scenarios. The loads at the lug points, the stress contours, and the hot spot tables of the developed system are compared with the result of the static analysis system.

• 한국의류학회지
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• 제47권1호
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• pp.137-151
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• 2023

Stationary 3D whole-body scanners generally require 5 to 20 seconds of scanning time and cannot effectively detect armpit and crotch areas. Therefore, this study aimed to analyze the accuracy of a photogrammetric technique using a multi-camera system. First, dimensional accuracy was analyzed using a mannequin scan, comparing the differences between the scan-derived measurements and the direct measurements, with an allowable tolerance of ISO 20685-1:2018. Only 2 of 59 measurement items (ankle height and upper arm circumference, specifically) exceeded the ISO 20685-1:2018 criteria. When compared with the results of the eight stationary whole-body scanners assessed by the literature, the photogrammetric technique was found to have the advantage of scanning the top of the head, armpit, and crotch areas clearly. Second, this study found the photogrammetric technique is suitable for obtaining the body scans because it can minimize the perform scanning, resulting in a reduction of measurement errors due to breathing and uncontrolled movements. The error rate of the photogrammetry method was much lower than that of stationary 3D whole-body scanners.

• Asian-Australasian Journal of Animal Sciences
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• 제15권5호
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• pp.725-731
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• 2002

This experiment was performed to understand the changes in plasma leptin in association with plasma IGF-1, body weight and ADG from early growing to late finishing stages of Holstein steers. Blood collection was performed by arterial vein puncture at selected monthly ages of 1 (54 kg), 2.6 (103 kg), 7.2 (205 kg), 13.5 (314 kg), 16.9 (414 kg), 22.2 (550 kg), 24.9 (626 kg) and 27.4 months (695 kg). The blood was analyzed for leptin using the multi-species leptin RIA with recombinant bovine leptin (rbleptin) as standard, plasma IGF-1 was also measured using RIA. Against the standard rbleptin, the multi-species Leptin RIA system's sensitivity, cross reactivity, slope and recovery of 41.0 ng/ml rbleptin in plasma were 4.9 ng/ml, 11.22%, -1.396 and 97.8%, respectively. Plasma leptin measured were more than 5.0 ng/ml, which enable multi-species RIA system to investigate plasma leptin in normal growing steers. Body weight resulted to a highly significant second-degree polynomial relationship with plasma leptin (q=0.54, p<0.0001) and plasma IGF-1 (q=0.44, p<0.0001) from 1 to 27.4 monthly ages. However, the second-degree polynomial curve of plasma leptin and IGF-1 differs showing a concave and convex curvilinear relationship, respectively. ADG was not significantly associated to plasma leptin (r=0.06, p>0.05) and plasma IGF=1 (r=0.06, p>0.05) from 1 to 27.4 monthly ages. Low coefficient, but significant associated increase of plasma leptin and IGF-1 (r=0.12, p<0.008) from 1 to 27.4 months was observed. The uncoordinated increases of plasma IGF-1 at growing and plasma leptin at fattening period, may indicate (1) indirect involvement of endogenous IGF-1 on leptin secretion, and (2) IGF-1 level may signify lean and bone accretion while plasma leptin may mirror body fatness across the monthly ages of Holstein steers.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2009년도 추계학술대회
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• pp.241-242
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• 2009

다동체 선체의 선형설계에서 선체 사이의 거리는 매우 중요한 설계 요소이다. 다동형 선박은 단동형 선박에 비하여 선체 주위의 비대칭적인 유동 변화, 두 선체 사이의 파형 간섭 등 복잡한 현상들로 인하여 그 체적 설계가 다소 어려운 것이 사실이다. 마찰저항에 비하여 조파저항의 영향이 큰 고속영역에서는 선형개발로 인한 조파저항 및 전체저항 감소할 수 있기 때문에 고속선에 이용되고 있다. 본 연구에서는 다동 몰수체 특히 두 선체 사이 간격에 따른 유동분석과 가시화 하여 유동장내 속도변화를 추적, 유동특성에 대한 실험적 연구를 수행하였다.

• 대한의용생체공학회:의공학회지
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• 제25권6호
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• pp.511-517
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• 2004

기존의 재활운동 장치들은 상지 또는 하지의 특정한 관절에 대해서만 재활운동이 가능하게 개발되었다. 따라서 여러 관절을 재활시키고자 할 경우, 그에 맞는 다양한 종류의 재활기구 들이 필요하다. 이러한 단점을 보완하기 위하여 본 연구에서는 각 관절에서 이루어지는 다양한 재활운동을 통합 구현하는 CMRS(CIM and Robotics Lab. Multi - joint Rehabilitation System)을 제안하였다. 이 시스템을 위해 인체의 상지 및 하지에 대한 기구학적 특성을 이용하여 각 관절의 회전 특성 및 좌표관계를 조사하였으며, 이와 같은 연구를 바탕으로 재활운동 기구 제작 시 알맞은 메커니즘을 제시하고. 다양한 재활 부위와 이를 재활 운동시키는 헤드부의 위치관계를 연구하였다. 시뮬레이션을 통하여 재활운동 시스템의 가능성을 판별하였고. 안정되고 편리한 위치 조정을 위한 베이스프레임을 개발하였다. 이를 고려하여 최종적으로 8개의 자유도를 가진 CMRS을 개발하였으며 다 관절을 하나의 시스템으로 재활 가능할 것이라 사료 된다.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2003년도 추계학술발표대회 개요집
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• pp.18-20
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• 2003

Optimal processing and system to produce the laser welded tube for one body formed bumper beam are studied. The calculated size of tube is a thickness of 1.4mm, diameter of 105.4mm and length of 2000mm. The tube is shaped from cool rolled high strength steel sheet(tensile strength: 60kgf/$\textrm{mm}^2$ grade). Two roll bending method is the optimal tube shaping process compared to UO-bending, bending on press brake, multi-step continuous roll forming and 3 roll bending methods. Weld quality monitoring and seam tracking along the butt-joint lengthwise to the tube axis are also studied. The longitudinal butt-joint is welded by the $CO_2$ laser welding system equipped with a seam tracker and plasma sensor. The constructed $CO_2$ laser tube welding system can be used for the precision seam tracking and the real-time monitoring of weld quality. Finally, the obtained laser welded tube can be used for one-body formed automobile bumper beam.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 봄 학술발표회 논문집
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• pp.489-494
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• 2001

This paper deals with a dynamic modeling of artillery system loaded by gun charge explosion during firing condition. Geometric and elastic gun data are used to modify a projectile interaction model. The maximum impact force on gun barrel was 15,000 N and the gun barrel moved about 1.3 m. A cannon bal] was presented to travel in the flexible gun, the traveling distance was about 23,000 m, and the angular velocity was about 10rad/sec. The artillery dynamic system using the multi-body dynamics enables us to obtain the data for the fatigue analysis.