• 한국자동차공학회논문집
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• 제21권3호
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• pp.30-42
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• 2013

This study investigates the effects of OSRVM mounting location and its configurations such as stalk height and housing height on the aerodynamic performance of the passenger car. In order to validate the flow solver, FLUENT which is very well known commercial code, the flow field around an Ahmed Body was analyzed numerically and compared with the experimental data. The predicted aerodynamic performance and flow patterns around a car show good agreements with the experimental data. Mounting location and stalk height should be designed while OSRVM is mounted on the car to evaluate the aerodynamic performance precisely. Housing height, however, may be designed independent of the car because the aerodynamic interference between housing height and car configuration is negligible.

• 한국자동차공학회논문집
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• 제18권5호
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• pp.91-99
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• 2010

The center of gravity on vehicle is a fundamentally important point for assessing and measuring the characteristics of vehicle dynamics. Especially, the center of gravity height on vehicles is the closest factor with respect to rollover accidents in a social issue nowadays. In this paper, the center of gravity height in conjunction with vehicle parameters of vehicle weight, driving axle and roof height after measured by vehicle weight and loading location by means of VCGM developed by KATRI with good performance that the accuracy was less than 0.6% and repeatability 0.3% for vehicles being used in the whole world was observed. As a result of study, the location of center of gravity height on vehicle was able to be estimated with only roof height on vehicle.

• 한국산학기술학회논문지
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• 제13권6호
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• pp.2779-2788
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• 2012

현재 주택시장은 주택증가율 상회와 미분양증가, 장기침체로 어려우나 주상복합은 복합화를 위주로 주거시설과 다양한 수요 시설을 조합할 수 있으며 초고층화하여 넓은 오픈스페이스와 우수한 조망을 확보하는 장점을 가진다. 그러나 스카이라인 형성 저해, 건축물의 높이에 의한 문제점이 야기된다. 이에 본 연구는 초고층 주상복합 건축물 입지유형에 따른 높이기준 및 세장비를 제안하는데 목적이 있다. 연구의 방법은 먼저 문헌조사를 통한 용어정리, 선행연구조사를 하고 사례조사로 서울시내의 16개의 사례를 중심으로 도시 계획적 차원과 건축물 단위의 높이와 관련한 사항을 조사하였다. 이를 기준으로 입지유형별 높이기준과 세장비를 제안하여 다음과 같은 결론을 가진다. 첫째, 도시계획적 차원에서 입지유형별 주상복합의 높이는 부도심을 중심으로 시작하여 높아지며, 150m이하에서 200m이상으로 제안이 가능하다. 둘째, 세장비는 초고층건축물과 달리 주상복합의 저층부의 면적이 크므로 1:3 이상으로 계획하여 시각통로를 두어 개방성 및 군(群)의 형성에 통일성 있게 계획한다. 셋째, 초고층 주상복합 건축물과 관련한 높이에 있어 특별건축구역제도 수정 및 초고층 관련 특별법을 제정한다.

• 디지털산업정보학회논문지
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• 제8권2호
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• pp.95-104
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• 2012

In this paper, an estimation of person height and 3D location of a moving person by using the pan/tilt-embedded stereo tracking system is suggested and implemented. In the proposed system, face coordinates of a target person is detected from the sequential input stereo image pairs by using the YCbCr color model and phase-type correlation methods and then, using this data as well as the geometric information of the stereo tracking system, distance to the target from the stereo camera and 3-dimensional location information of a target person are extracted. Basing on these extracted data the pan/tilt system embedded in the stereo camera is controlled to adaptively track a moving person and as a result, moving trajectory of a target person can be obtained. From some experiments using 780 frames of the sequential stereo image pairs, it is analyzed that standard deviation of the position displacement of the target in the horizontal and vertical directions after tracking is kept to be very low value of 1.5, 0.42 for 780 frames on average, and error ratio between the measured and computed 3D coordinate values of the target is also kept to be very low value of 0.5% on average. These good experimental results suggest a possibility of implementation of a new stereo target tracking system having a high degree of accuracy and a very fast response time with this proposed algorithm.

• Steel and Composite Structures
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• 제38권6호
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• pp.671-690
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• 2021

Seismic responses of RC core wall with two outriggers are investigated in this study. In the models analyzed here, one of the outriggers is fixed at the top of the building and the second is placed at different levels along the height of the system. Each of the systems resulting from the placement of the outrigger at different locations is designed according to the prescriptive codes. The location of the outrigger changes along the height. Linear design of all the structures is accomplished by using prescriptive codes. Buckling restrained braces (BRBs) are used in the outriggers and forward directivity near fault and far fault earthquake record sets are used at maximum considered earthquake (MCE) level. Results from nonlinear time history analysis demonstrate that BRB outriggers can change the seismic responses like force distribution and deformation demand of the RC core-walls over the height and lead to the new plastic hinge arrangement over the core-wall height. Plasticity extension in the RC core wall occurs at the base as well as adjacent to the outrigger levels. Considering the maximum inter-story drift ratio (IDR) demand as an engineering parameter, the best location for the second outrigger is at 0.75H, in which the maximum IDR at the region upper the second outrigger level is approximately equal to the corresponding value in the lower region.

• 한국입자에어로졸학회지
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• 제17권2호
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• pp.37-42
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• 2021

Although the installation of droplet protection screen (DPS) is known to prevent droplet transmission, there is still a lack of knowledge in effectiveness of DPS installation to block the airborne transmission. In this study, the prevention ability of DPS against airborne transmission was evaluated according to the DPS height. When the DPS was not installed, the maximum concentration of PM1.0 at the location opposite to infected person was 35% of that at the infected person location. When the DPS was installed, the DPS effectively prevented the airborne transmission, consequently approximately 7% of generated particles were measured at the opposite location from particle generation position (infected person location). The prevention ability of DPS increased with DPS height, the maximum prevention efficiency of 95.1% was obtained when the DPS height was 900mm. Moreover, the speed of airborne transmission was delayed by installation of DPS, and the delay time increased with DPS height.

• Imaging Science in Dentistry
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• 제51권3호
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• pp.243-250
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• 2021

Purpose: The objective of this study was to evaluate the amount of height available for a maxillary sinus augmentation procedure without blocking the ostium and jeopardizing the drainage of the ostiomeatal complex using cone-beam computed tomography (CBCT) imaging. Materials and Methods: A total of 200 sinonasal complexes comprising 100 dentate and 100 edentulous scans were retrospectively assessed using CBCT. Invivo 5.0, a CBCT reconstruction program, was used for image evaluation. The coronal section demonstrating the ostiomeatal complex was selected as a reference view to perform measurements of the sinus. The measurements were done by 2 evaluators in separate sessions. Comparative analyses of measurements were performed between dentate and edentulous patients and between male and female patients. Results: The safe height to which the sinus can be elevated without compromising the integrity of the ostiomeatal complex was calculated for each sinus. In the presence of significant mucosal thickening, the height available for augmentation was calculated by subtracting the height of mucosal thickening from the sinus floor to the location of the ostium. In this study, the available height was approximately 27.05 mm for dentate and 23.40 mm for edentulous patients. The inter-operator reliability was excellent for all the parameters evaluated. Conclusion: This retrospective study with a limited number of patients from a single university-based site shows that CBCT is valuable in evaluating the location and patency of the ostium for planning sinus augmentation procedures for dental implant placement.

• 한국전산유체공학회지
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• 제3권2호
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• pp.52-64
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• 1998

Numerical simulations on the flowfield of lifting chamber for Wing-In-Ground vehicle were performed using Fluent/UNS 4.2 software. The trend of lifting force in lifting chamber and parametric study of geometric and fluid variables were primarily investigated. Selected parameters for investigation are inlet velocity, height between chamber and water level, depth of the skirt, location of inlet, variaton of height at bow and stern. Also, air capturing capabilities from downstream of the propeller were evaluated at the air inlet. The lifting force was increased linearly with the increased of inlet velocity and nonlinearly with the decrease of height force was increased with increased depth. It turned out to have very minor effect on lifting force to change the location of air inlet for lifting chamber, installed on top surface. Tilting the vehicle when it was lifted, the lifting forces, generated in each case, showed no appreciable changes.

• 설비공학논문집
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• 제21권11호
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• pp.599-605
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• 2009

This paper presents a numerical evaluation of the flow rate of air conditioner outdoor unit by investigating the effects of fan location and shroud shape. To determine optimal design parameters, we investigated the exhaust flow rate by changing shroud height, fan height, fan guide height, and fan width. The 3rd order central composite design was performed to select three most important parameters affecting the exhaust flow rate. According to the result of response surface method, the exhaust flow rate of the optimum model increased by 6.25% compared to that of the base model.

• Journal of Acupuncture Research
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• 제35권1호
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• pp.37-40
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• 2018

Background: The purpose of this study was to compare the first branch of the bladder meridian (FBBM) as determined by the proportional bone measurement method (PBMM), to the line formed by the erector spinae muscle group, and to establish an academic basis for selection of acupuncture points and needling. Methods: Sixty participants were divided into 3 groups based on body mass index (BMI) and into 2 groups based on waist/height ratios. The distance from the midline of the spine to the first branch of the bladder meridian with PBMM (DFBBM), and the distance from the midline of the spine to the most elevated fleshy region of the erector spinae (DMEFR), at the same level as the inferior border of the spinous processes of L1-L5, were measured. The DFBBM and the 5 DMEFRs were then analyzed according to BMI and the waist/height ratio. Results: DFBBM was statistically different from DMEFR in all back-shu points in the lumbar region. DFBBM was not significantly different from DMEFR in the groups with a high BMI or waist/height ratio. However, there was a statistical difference in the groups with a low or moderate BMI or low waist/height ratio. Conclusion: Since the location of the most elevated fleshy region of the erector spinae does not coincide with the location of the FBBM, the selection of back-shu points in the lumbar region must be performed precisely by PBMM.