• 대한의용생체공학회:의공학회지
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• 제17권1호
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• pp.25-32
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• 1996

Hough변환을 이용하여 정자의 행태학적 특성을 분석하는 새로운 방법을 개발하였다. 이 방법은 정자의 머리부분이 주위의 배경과 밝기의 차이를 갖는다는 특성과 함께 그 형태가 타원에 근접한다는 특성에 근거하고 있다. 정자의 머리부분은 타원을 나타내는 5개의 파라메터로 표현되고, 최적의 파라메터 값이 반복적인 Hough 변환에 의하여 검출된다. 일차적으로 정자가 있는 영역을 선택한다. Hough변환을 이용한 계산을 가능하게 하기 위하여 Hough변환된 공간의 크기를 최소한으로 줄이고, 검출된 오차가 최소화되는 방향으로 검사영역을 이동 시켜가며 최적의 파라메터들을 도출한다. 형태학적 특성을 나타내는 지표들은 정자의 형태를 나타내는 타원의 다섯개 파라메터들로부터 계산된다.

• 설비공학논문집
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• 제27권12호
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• pp.620-625
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• 2015

The summer climate is very hot and humid in Korea. Humidity is an important factor in determining thermal comfort. Recently, research on dehumidification device development has been attempted to save the energy required for operating the dehumidifier. Existing dehumidification systems have disadvantages such as wasting energy to drive the compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature. Therefore. they don't have to consume cooling energy. In this paper, the installation conditions for a membrane system were analyzed to improve the shape and optimum performance of the system. The results showed that the distance between elements was the critical system design factor, and that a distance of 20 mm was the optimal condition for the pressure drop and flow characteristics of the internal air flow.

• 산업경영시스템학회지
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• 제32권2호
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• pp.76-84
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• 2009

Since too much information has been generated, it became very difficult to find out valuable and necessary information. In order to deal with the problem of information overload, the taxonomy for information visualization techniques has been based upon visualized shapes such as tree map, fisheye view and parallel coordinates, so that it was difficult to choose the right representation technique by data characteristics. Therefore, this study was designed to introduce a new taxonomy for the information visualization by data characteristics which defined by space (3D vs. multi-dimensions), time (continuous vs. discrete), and relations of data (qualitative vs. quantitative). To verify the new taxonomy, forensic data which were generated to investigate the culprit of network security was used. The result showed that the new taxonomy was found to be very efficient and effective to choose the right visualized shape for forensic data for network security. In conclusion, the new taxonomy was proven to be very helpful to choose the right information visualization technique by data characteristics.

• 전자공학회논문지
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• 제53권1호
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• pp.22-26
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• 2016

본 논문에서는 공 모양의 구조를 이용하여 공진형 무선 전력 전송용 송 수신기를 설계 및 구현하였다. 제안된 송신기의 코일을 공 모양으로 감음으로써 3차원의 공간으로 자계 에너지를 방사하도록 하였다. 송신기의 각각의 면을 나선 구조로 함으로써 높은 Q 값을 얻을 수 있도록 설계하였다. 이것은 기존의 무선 전력 전송 시스템에서 위치에 따라서 전송효율이 변하는 문제점을 해결하였다. 그리고 3차원에서의 공진형 무선 전력 전송을 가능하게 한다. 이때의 공진주파수는 6.78 MHz이며, 송 수신기 사이 거리가 200 mm일 때, 3차원 전 방향에서 40% 이상의 전송 효율을 얻을 수 있었다.

• 미생물학회지
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• 제24권3호
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• pp.197-203
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• 1986

Streptomyces lavendulae에서 생성된 원형질체 및 원형질체 융합과정에 대한 미세구조 및 행태학적 관찰을 투과 전자현미경과 주사전자현미경을 사용하여 행하였다. 생성된 원행질체들은 고장액에서 대체로 안정하였으나 간혹 변형된 원형질체들이 관찰되었다. 원형질체 융합은 접촉지역 융합지역, 분리지역 형성과정을 차례로 거치면서 선행되는 것이 관찰되었다. 이러한 사실은 세포막 구조의 변화와 이원형의 소실에 의하여 뒷받침이 될 수 있으으로 이러한 변화들을 융합과정에서의 각 단계로 해석하는 것이 가능하리라 사료된다.

• 대한두개안면성형외과학회지
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• 제17권2호
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• pp.77-81
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• 2016

Background: Asymmetry of the infraorbital rim can be caused by trauma, congenital or acquired disease, or insufficient reduction during a previous operation. Such asymmetry needs to be corrected because the shape of the infraorbital rim or midfacial skeleton defines the overall midfacial contour. Methods: The study included 5 cases of retruded infraorbital rim. All of the patient underwent restoration of the deficient volume using polyethylene implants between June 2005 and June 2011. The infraorbital rim was accessed through a subciliary approach, and the implants were placed in subperiosteal space. Surgical outcomes were evaluated using preoperative and postoperative computed tomography studies. Results: Implant based augmentation was associated with a mean projection of 4.6 mm enhancement. No postoperative complications were noted during the 30-month follow-up period. Conclusion: Because of the safeness, short recovery time, effectiveness, reliability, and potential application to a wide range of facial disproportion problems, this surgical technique can be applied to midfacial retrusion from a variety of etiologies, such as fracture involving infraorbital rim, congenital midfacial hypoplasia, lid malposition after blepharoplasty, and skeletal changes due to aging.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.450-453
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• 2000

In this paper, an automated segmentation algorithm is proposed for MR brain images using T1-weighted, T2-weighted, and PD images complementarily. The proposed segmentation algorithm is composed of 3 steps. In the first step, cerebrum images are extracted by putting a cerebrum mask upon the three input images. In the second step, outstanding clusters that represent inner tissues of the cerebrum are chosen among 3-dimensional (3D) clusters. 3D clusters are determined by intersecting densely distributed parts of 2D histogram in the 3D space formed with three optimal scale images. Optimal scale image best describes the shape of densely distributed parts of pixels in 2D histogram. In the final step, cerebrum images are segmented using FCM algorithm with it’s initial centroid value as the outstanding cluster’s centroid value. The proposed segmentation algorithm complements the defect of FCM algorithm, being influenced upon initial centroid, by calculating cluster’s centroid accurately And also can get better segmentation results from the proposed segmentation algorithm with multi spectral analysis than the results of single spectral analysis.

• 한국실내디자인학회논문집
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• 제21권6호
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• pp.54-61
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• 2012

The aim of this study is to understand the plan characteristics used in unit floor planning mainly with examples of mixed-use residential tall buildings. The study will extract plan characteristics mainly using the graph expressive technique with essential information of the zoning function of residential space, rather than merely analyzing the various construction floor plans by type. The research method involves studying a group of 50-story buildings (over 200 meters) which were built between 2002 and 2008. Among 6 high-rise residential buildings case, we extract the most preferred type from 34 types, And then we simply classify rooms in 3 zoning, the master, living and children's zones. Finally we analyze the correlation among 3 simple zone and then extract some model type. The results of this study revealed three main findings. First, using the 3 functional zones, the shape of the main building and the unit floor plan can be analyzed simply even when they appear to be complicated. Second, we can extract common features when we analyze the unit floor plan from the viewpoint of the penetrability among 3 zoning. Third, we can extract 2 types when we analyze the unit floor plan from the viewpoint of 3 connected functional zoning concepts.

• 한국실내디자인학회논문집
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• 제18권3호
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• pp.102-113
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• 2009

The SARS virus began to appear and spread in North America and Southeast Asia in the early 2000' s, infecting and harming many people. In the process of examining the causes for the virus, studies on the airborne SARS virus and the way it spread were carried out mainly in the medical field. In the field of architecture, studies were done on the diffusion of air pollutants in buildings using gases such as $CO_2$, $N_2O$, or $SF_6$, but research on virus diffusion was limited. There were also explanations of only the diffusion process without accurate information and discussion on virus characteristics. The aim of this study is to analyze the physical characteristics of airborne virus, consider the possibility of using coupled analysis model and tracer gas for analyzing virus diffusion in building space and, based on reports of how the infection spread in a hospital where SARS patients were discovered, analyze infection risk using tracer gas density and also diffusion patterns according to the location, shape, and volume of supply diffusers and exhaust grilles. This paper can provide standards and logical principles for evaluating various alternatives for making decisions on vertical or horizontal ward placement, air supply and exhaust installation and air volumes in medium or high story medical facilities.

• 대한기계학회논문집B
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• 제33권1호
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• pp.60-68
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• 2009

The steam reformer for hydrogen production from methane is studied by a numerical method. Langmuir- Hinshelwood model is incorporated for catalytic surface reactions, and the pseudo-homogeneous model is used to take into account local equilibrium phenomena between a catalyst and bulk gas. Dominant chemical reactions are Steam Reforming (SR) reaction, Water-Gas Shift (WGS) reaction, and Direct Steam Reforming (DSR) reaction. The numerical results are validated with experimental results at the same operating conditions. Using the validated code, parametric study has been numerically performed in view of the steam reformer performance. As increasing a wall temperature, the fuel conversion increases due to the high heat transfer rate. When Steam to Carbon Ratio (SCR) increases, the concentration of carbon monoxide decreases since WGS reaction becomes more active. When increasing Gas Hourly Space Velocity (GHSV), the fuel conversion decreases due to the heat transfer limitation and the low residence time. The reactor shape effects are also investigated. The length and radius of cylindrical reactors are changed at the same catalyst volume. The longer steam reformer is, the better steam reformer performs. However, system energy efficiency decreases due to the large pressure drop.