• Title/Summary/Keyword: Pros.

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A study on the overhaul method for a Tandem type EDG on Nuclear Power Plant (원자력발전소 Tandem 형 비상디젤발전기의 최적 정비 방안 연구)

  • Han, Sung-Heum;Lim, Woo-Sang;Ha, Che-Wung
    • Proceedings of the KIEE Conference
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    • 2008.07a
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    • pp.2036-2037
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    • 2008
  • An Emergency Diesel Generator (EDG) manufactured by a French company Wartsila SACM, is a tandem type engine, consisted of two 10 cylindered diesel engines on each side. Manual provided by the manufacturer states that engine bearing requires inspection every 15 years. However, it is difficult for an inspector to access through a manhole located in the lower compartment of engine. Furthermore, during a routine or scheduled maintenance, it is not possible to disassemble main engine bearing and crank shaft, and perform inspection. Two methodologies are suggested here to resolve the problem. One method is to lift the engine and partially perform the maintenance service, and the other method is to disassemble the engine completely and to perform maintenance service by the manufacturer. Pros and cons of two methodologies were thoroughly compared.

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Controversies on governing the rates of protein evolution

  • Choi, Sun-Shim
    • Interdisciplinary Bio Central
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    • v.1 no.3
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    • pp.11.1-11.5
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    • 2009
  • One of the main issues of molecular evolution is to reveal the principles dictating protein evolutionary rates. A traditional hypothesis posits that protein evolutionary rates are mostly determined by the average functional importance of amino acids in a given protein. Thus the correlations of evolutionary rates with different variables such as PPI, gene essentiality and expression abundance have been studied to test the traditional hypothesis. Recently, mRNA expression abundance among the variables has drawn much attention, not only because it shows relatively strong correlation with protein evolutionary rates, but also because of the controversies surrounding an alternative hypothesis against the traditional one. Here, I will give an overview over the traditional hypothesis, and summarize the different variables that have been found to correlate with protein evolutionary rates. Then I will introduce pros and cons on the two different hypotheses.

Comparative study on displacement measurement sensors for high-speed railroad bridge

  • Cho, Soojin;Lee, Junhwa;Sim, Sung-Han
    • Smart Structures and Systems
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    • v.21 no.5
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    • pp.637-652
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    • 2018
  • This paper presents a comparative study of displacement measurement using four sensors that are being used in the field: they are a ring gauge, a laser Doppler vibrometer (LDV), a vision-based displacement measurement system (VDMS), and an optoelectronic displacement meter (ODM). The comparative study was carried out on a brand-new high-speed railroad bridge designed to produce displacements within a couple of millimeters under the loading of a high-speed train. The tests were carried out on a single-span steel plate girder bridge two times with different train loadings: KTX and HEMU. The measured displacement is compared as raw and further discussion was made on the measurement noise, peak displacement, and frequency response of four sensors. The comparisonsare summarized to show the pros and cons of the used sensors in measuring displacement at a typical high-speed railroad bridge.

Real-time Interactive Particle-art with Human Motion Based on Computer Vision Techniques (컴퓨터 비전 기술을 활용한 관객의 움직임과 상호작용이 가능한 실시간 파티클 아트)

  • Jo, Ik Hyun;Park, Geo Tae;Jung, Soon Ki
    • Journal of Korea Multimedia Society
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    • v.21 no.1
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    • pp.51-60
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    • 2018
  • We present a real-time interactive particle-art with human motion based on computer vision techniques. We used computer vision techniques to reduce the number of equipments that required for media art appreciations. We analyze pros and cons of various computer vision methods that can adapted to interactive digital media art. In our system, background subtraction is applied to search an audience. The audience image is changed into particles with grid cells. Optical flow is used to detect the motion of the audience and create particle effects. Also we define a virtual button for interaction. This paper introduces a series of computer vision modules to build the interactive digital media art contents which can be easily configurated with a camera sensor.

Differences in Processes of Change, Decisional Balance, and Temptation Across the Stages of Change for Smoking Cessation (금연 변화 단계에 따른 변화 과정, 의사결정 균형, 흡연 유혹의 차이)

  • Son Haeng-Mi
    • Journal of Korean Academy of Nursing
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    • v.35 no.5
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    • pp.904-913
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    • 2005
  • Purpose: The purpose of this study was to investigate smoking cessation behavior of male taxi drivers in Korea on the basis of the Transtheoretical model(TTM), and to validate the usefulness of TTM. Method: Data were collected using a self-reported questionnaire including smoking history and major factors of TTM from 208 subjects who were current smokers or ex-smokers. Data were analyzed by descriptive statistics and ANOVA. Result: Most subjects ($85.1\%$) were current smokers. Stages of change were precontemplation ($44.7\%$) and contemplation ($27.4\%$). Subjects in precontemplation stages had the lowest mean score in processes of change and the highest mean scores in decisional balance(pros) and temptation(positive affective, habitual/craving). According to stages of change, there were statistically significant differences in processes of change, decisional balance, and temptation. Conclusion: This study supported the generalization of TTM. As this study showed that the subjects didn't have motivation in smoking cessation, applying tailored smoking cessation programs for taxi drivers is needed.

Distributed Mobility Management Strategy with Pointer Forwarding Technique

  • Wie, Sunghong;Jang, Jaeshin
    • Journal of information and communication convergence engineering
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    • v.13 no.4
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    • pp.248-256
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    • 2015
  • With the dramatic increase in mobile traffic in recent years, some of the limitations of mobility management frameworks have magnified. The current centralized mobility management (CMM) strategy has various problems, such as a suboptimal routing path, low scalability, signaling overhead, and a single point of failure. To overcome these weaknesses in the CMM strategy, the Internet Engineering Task Force has been discussing distributed mobility management (DMM) strategies. The fundamental concept of a DMM strategy is to distribute the mobility anchors closer to the users. While the distribution of mobility anchors results in low-cost traffic delivery, it increases the signaling cost. To reduce this higher signaling cost, we propose a new DMM strategy applying the pointer forwarding technique. The proposed strategy keeps the existing tunnels and extends the traffic path as much as possible. In this paper, we analyze the performance of the pointer forwarding-DMM strategy and discuss its pros and cons.

실리콘 박막 태양전지를 위한 CdSe계 양자점 광변환구조체

  • Sin, Myeong-Hun
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.135.2-135.2
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    • 2014
  • Photon conversion technology for thin film solar cells is reviewed. The high-energy photons which are hardly absorbed in solar cells can be transformed the low energy photon by the photon conversion process such as down conversion or down shift, which can improve the solar cell efficiency over the material limit. CdSe-based quantum dot materials commonly used in LED can be used as the photon conversion layer for Si thin film solar cells. The photon conversion structure of CdSe-based quantum dot for Si thin film solar cells will be presented and the pros and cons for the Si thin film solar cells integrated with the photon conversion layers will be discussed.

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A study on the flatness of automotive torque-angle sensors (자동차 토크앵글센서(TAS)의 평면 정밀도에 관한 연구)

  • Yoon, Sean-Jhin;Cho, Yong-Moo
    • Design & Manufacturing
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    • v.12 no.2
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    • pp.11-15
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    • 2018
  • In this study, we proposed three analysis methods to calculate the flatness of torque-angle sensors (TAS). We introduced two statistical and one geometrical methods in evaluating the precision of the flat plane in the axis direction for TAS. To verified the results, we fabricated TAS and a reference sample using a injection molding machine, mold, polyester as a raw material. We measured ($x_i$, $y_i$) position using 3D contact automated system and applied three analysis methods developed for TAS and a reference sample to see the feasibility. While each analysis method has its own pros and cons, the analysis using the shortest optimal distance was the most precise technique for the flatness evaluation of TAS components.

Tuning the Architecture of Support Vector Machine: The Case of Bankruptcy Prediction

  • Min, Jae-H.;Jeong, Chul-Woo;Kim, Myung-Suk
    • Management Science and Financial Engineering
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    • v.17 no.1
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    • pp.19-43
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    • 2011
  • Tuning the architecture of SVM (support vector machine) is to build an SVM model of better performance. Two different tuning methods of the grid search and the GA (genetic algorithm) have been addressed in the literature, each of which has its own methodological pros and cons. This paper suggests a combined method for tuning the architecture of SVM models, which employs the GAM (generalized additive models), the grid search, and the GA in sequence. The GAM is used for selecting input variables, and the grid search and the GA are employed for finding optimal parameter values of the SVM models. Applying the method to a bankruptcy prediction problem, we show that SVM model tuned by the proposed method outperforms other SVM models.

Subcision Using a Spinal Needle Cannula and a Thread for Prominent Nasolabial Fold Correction

  • Lee, Sang-Yeul;Sung, Kun-Yong
    • Archives of Plastic Surgery
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    • v.40 no.3
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    • pp.256-258
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    • 2013
  • Deepening of the nasolabial crease is an esthetically unpleasing aging phenomenon occurring in the midface. Various treatment modalities have been introduced to improve the appearance of prominent nasolabial folds, all of which have pros and cons. Currently, a minimally invasive technique using synthetic dermal fillers is most commonly used. A simple and easy subcision procedure using a wire scalpel has also been used and reported to be effective for prominent nasolabial fold correction, with minimal complications. As an alternative to the wire scalpel, we used a 20-gauge metal type spinal needle cannula (Hakko Co.) and 4-0 Vicryl suture (Ethicon Inc.) for subcision of nasolabial folds. This technique is less expensive than the use of a wire scalpel and easily available when needed. Therefore, on the basis of favorable results, our modified subcision technique may be considered effective for prominent nasolabial fold correction.