• 한국세라믹학회지
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• 제47권2호
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• pp.99-105
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• 2010

The electrical transport properties of mayenite ($Ca_{12}Al_{14}O_{33}$ or $12CaO{\cdot}7Al_2O_3$; mostly abbreviated as $C_{12}A_7$) can be controlled in a wide range by varying the oxygen deficiency: At high temperatures mayenite becomes either an oxygen solid electrolyte, a mixed ionic/electronic conductor or an inorganic electride with metal-like properties upon chemical reduction (removing oxygen). The underlying defect chemistry can be understood on the basis of a relatively simple model-despite the complex cage structure: A point defect model based on the assumption that the framework $[Ca_{12}Al_{14}O_{32}]^{2+}$ acts as a pseudo-donor describes well the high temperature transport properties. It accounts for the observed conductivity plateau at higher oxygen activities and also describes the experimentally observed oxygen activity dependence of the electronic conductivity with -1/4 slope at temperatures between 800 and $1000^{\circ}C$. Doping effects in mayenite are still not well explored, and we review briefly the existing data on doping by different elements. Hydration of mayenite plays a crucial role, as Mayenite is hygroscopic, which may be a major obstacle for technical applications.

• 전자공학회논문지S
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• 제34S권10호
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• pp.59-70
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• 1997

Until now, considerable progress has been made in the application of range finding techanique performing direct 3-D measurement from the object. However, ther are few use of the method in the area of the application of material handing. We present a range finding vision system consisting of static and dynamic range finders to automate a reclaimer used for material handling. A static range finder detects range data of the front part of the piles of material, and a height map is obtained from the proposed image processing algorithm. The height map is used to calculate the optimal job path as features for required information for material handling function. A dynamic range finder attached on the side of the arm of the reclaimer detects the change of the local properties of the material with the handling function, which is used for avoiding collision and detecting the ending point for changing direction. the developed vision systm was applied to a 1/20 simulator and the results of test show that it is appropriate to use for automating the material handling.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.167-173
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• 2010

In this study, flow structure in a three-stage centrifugal compressor for LNG Plant with the refrigerant, Propane, was numerically investigated at the design point of the compressor using a commercial code. Flow characteristics in the passages of impeller and vaneless diffuser were analyzed in detail including velocity vector, Mach number and pressure contours in blade spanwise and meridional plane for each stage. The estimation on the one-dimensional output from the preliminary design and three-dimensional shape of the impeller blade was performed through the flow analysis. The verification for designed compressor was carried out from three-dimensional Navier-Stokes analysis. The results will be used as reference data for a new design of 3-D impeller shape to improve propane refrigerant compressor performance.

• 대한전자공학회논문지
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• 제20권3호
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• pp.6-12
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• 1983

시각 자극을 주었을 때 이에 유발되어 나타나는 전위를 두피에 19개의 전극을 부착하고 측정하여 500Hz의 표본화 주파수로 A/D변환하였다. 이들 전위들의 분포로부터 각 전극의 좌표에 의해서 결정된 웨이팅 매트릭스를 사용하여 전위 분포의 중심점을 구하고 시간에 따른 이동 상태를 5명의 대상인과 4명의 비정상인에 대하여 분석하였다. 정상인에게서는 자극에 의한 시각적 정보가 시신경 경로를 통해서 전기적 신호로 전달되는 형태를 파악할 수 있었고, 비정상인의 경우에는 이러한 현상이 나타나지 않는 것을 발견하였다. 또한 본 연구의 중심점 추적의 방법과 다이폴 소오스 모델, 포인트 소오스 모델과의 관계를 검토 분석하였다.

• Earthquakes and Structures
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• 제4권5호
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• pp.471-487
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• 2013

Performance of a prototype base isolated building located at Indian Institute of Technology, Guwahati (IITG) has been studied here. Two numbers of three storeyed single bay RCC framed prototype buildings were constructed for experimental purpose at IITG, one supported on conventional isolated footings and the other on a seismic isolation system, consisting of lead plug bearings. Force balance accelerometers and a 12 channel strong motion recorder have been used for recording building response during seismic events. Floor responses from these buildings show amplification for the conventional building while 60 to 70% reduction has been observed for the isolated building. Numerical models of both the buildings have been created in SAP2000 Nonlinear. Infill walls have been modeled as compression struts and have been incorporated into the 3D models using Gap elements. System identification of the recorded data has been carried out using Parametric State Space Modeling (N4SID) and the numerical models have been updated accordingly. The study demonstrates the effectiveness of base isolation systems in controlling seismic response of isolated buildings thereby leading to increased levels of seismic protection. The numerical models calibrated by relatively low level of earthquake shaking provides the starting point for modeling the non-linear response of the building when subjected to strong shaking.

• 성인간호학회지
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• 제26권2호
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• pp.214-222
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• 2014

Purpose: This study was to identify factors predicting the occurrence of depression among patients with hepatitis C treated with Peg-interferon. Methods: The subjects were 134 patients treated with Peg-interferon after the diagnosis with hepatitis C at the D University Hospital and 3 hospitals located in Busan, South Korea. The predictors of depression were identified by measuring the general characteristics of the subjects and their disease-related characteristics, social support, sleep disorders, and degree of side effects by interferon. The data were analyzed with a t-test, ANOVA, and logistic regression using the SPSS/WIN 18.0 program. Results: Sixty-six point four percent of the subjects suffered from mild to more severe depression. Fatigue, hair loss, itching, and sleep disorders turned out to be significant predictors. In addition, the explanatory power of these variables for the occurrence of depression was 70%. Conclusion: Sleep disorders and drug side effects were determined to have significant influence on the development of depression in hepatitis C patients treated with Peg-interferon. Therefore, the development of nursing intervention programs aimed to prevent depression by effectively managing sleep disorders and side effects is mandated in future to help the given population.

• 자원환경지질
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• 제10권4호
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• pp.185-198
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• 1977

This paper is the result of a petrochemical study on the Jongam granite mass which intruded metasediments of Ogcheon zone, locating about 10km northwest from Miweon town, and the mass is $2.5km^2$ in area. In this study, the granite was petrographically analysed in such ways, modal analysis, myrmekite analysis, petrochemical study analysis and tectonic analysis of joint system. The findings are as follows: 1) The area of the granite distributed is a basin surrounded by metasediments. The granite is magma origin. 2) The major mineral composition of the granite are quartz, plagioclase, microcline orthoclase and biotite, and accessaries are muscovite, sericite, magnetite, zircon and sphene. 3) In triangles of $Qu-K{\cdot}fp-PI$, Bi-Or-Hb+Mt and Qu-Ab-Or, the data point areas are similar to those of the NW zone of D.S. Lee (1971) 4) The granite mass can be divided into three granites; quartz monzonite, granodiorite and biotite granite, by petrological aspect in detail. 5) It shows inverse ratio of content between quartz and plagioclase. 6) The myrmekite-texture of the granite are stem type and dominating in northern part. 7) In the tectonic analysis of joint, the strikes are almost constant in direction, N-S direction of dominant joints 8) The geological age of the granites estimated to be Jurassic in age. 9) According to the mineralogical distribution and joint systen, the intrusion direction of the granite magma was infered as from north to south.

• 상하수도학회지
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• 제22권6호
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• pp.647-655
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• 2008

Sewer Rehabilitation Project (SRP) is planed, designed and constructed to perform its intended performance as sewerage delivery systems. Recently, a subject of performance evaluation methodology development for SRP has become a great deal of concern among researchers in Korea. From the view point of Sewage Treatment Plant (STP), however, the estimation of improvement efficiency for SRP is in lack of reliability due to the fact that affections for the treatment efficiency and operating condition are not reflected on SRP design and construction. In this study, statistical methodology was used in the analysis of data, which are taken during 1,186 days ($1^{st}$ Jan. 2005 - $31^{th}$ Mar. 2008) from the influent, effluent and operating conditions of full-scale STP($25,000m^3/d$). Then the effect of SRP on the influent characteristics and operating conditions changing was compared and evaluated. Results from the statistical evaluation show that SRP causes characteristic changes in influent and exerts a significant effect especially on the performance of STP.

• 한국소음진동공학회논문집
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• 제25권8호
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• pp.568-574
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• 2015

The present study was conducted by using stereo pattern recognition method(SPR method) to measure the displacement and vibration of an airplane wing in flight condition. A SPR based measurement system was developed using two visible light stereo cameras. The visible light stereo images were processed to obtain marker points by adaptive threshold method and marker filtering technique. The marker points were used to reconstruct 3D point, displacement, and vibration data. The SPR system was installed on F-16 fighter. The wing displacement and vibration were measured in flight condition. Therefore, this paper presents a possibility that SPR based measurement system using visible light stereo camera can be very useful for measuring displacement and vibration of an airplane in flight condition.

• 패션비즈니스
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• 제5권3호
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• pp.73-84
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• 2001

The purpose of this study is to apply fundamental data of impression formation research by analysing and observing the various facial image that can be effected from hair style as well as be helpful for choosing suitable hair style for T.P.O in modern society. This study targeted 305 college women in Daegu and Gyung-book area. Hair Style Image Scale(HSIS)was used the scale of seven point modified the S-D(Semantic Differential) method. The analysis of impression formation effect of hair style using SPSS WIN package have completed from the principal component analysis by Varimax perpendicular rotation method and ANOVA was used to recognize the difference in impression formation according to hair style change. In the case of statistical difference was appeared, LSD post-verification was applied for that. The conclusions of this study is as followed ; 1. The factors of impression formation effected by hair style were classified as goodwill factor, refinement factor, elegance factor and individuality factor. 2. In terms of goodwill factor, long hair style showed highest level and short cut hair, bobbed hair in an order. In refinement factor, there was no difference between short cut hair and bobbed hair and both of them was higher than long hair. In elegance factor, long hair was highest and bobbed hair was lowest. In individuality factor, short cut hair and bobbed hair higher than long hair and no difference between short cut hair and bobbed hair.