• 한국수소및신에너지학회논문집
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• 제13권4호
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• pp.259-269
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• 2002

A battery based on the lithium/elemental sulfur redox couple has the advantage of high theoretical specific capacity of 1,675 mAh/g-sulfur. However, Li/S battery has bad cyclic durability at room temperature due to sulfur active material loss resulting from lithium polysulfide dissolution. To improve the cycle life of Li/S battery, PEGDME (Poly(ethylene glycol) dimethyl ether) 500 containing 1M LiTFSI salt which has high viscosity was used as electrolyte to retard the polysulfide dissolution and nano-sized $Mg_{0.6}Ni_{0.4}O$ was added to sulfur cathode as additive to adsorb soluble polysulfide within sulfur cathode. From experimental results, the improvement of the capacity and cycle life of Li/S battery was observed( maximum discharge capacity : 1,185 mAh/g-sulfur, C50/C1 = 85 % ). Through the charge-discharge test, we knew that PEGDME 500 played a role of preventing incomplete charge-discharge $behavior^{1,2)$. And then, in sulfur dissolution analysis and rate capability test, we first confirmed that nano-sized $Mg_{0.6}Ni_{0.4}O$ had polysulfide adsorbing effect and catalytic effect of promoting the Li/S redox reaction. In addition, from BET surface area analysis, we also verified that it played the part of increasing the porosity of sulfur cathode.

• 한국항공우주학회지
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• 제38권6호
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• pp.547-556
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• 2010

항공기의 안전성 확보 및 투하되는 탄의 정확도 증대를 위한 새로운 개념의 활공비행체 개발이 많은 기업에서 진행 중에 있다. 항공기의 장착 공간 및 활공거리 증대를 고려하여 세장비가 큰 전개되는 날개를 채택하는 것이 일반적이다. 큰 세장비의 날개 구조물은 상대적으로 낮은 강성에 의하여 과도한 탄성변형 뿐 아니라 플러터 발생의 가능성이 높아지게 된다. 본 연구는 큰 세장비 날개에 대하여 유체-공력 연계기법을 이용, 구조변형에 의한 공력특성의 변화 및 플러터 발생가능성에 대하여 검토하였다. 공기력 계산을 위하여 FLUENT 코드가 구조 동특성 해석을 위하여 ABAQUS 상용코드가 사용되었으며, 국부지지 방사기저함수로 구성된 Code-bridge를 이용한 입력 자료의 보간 및 사상을 수행하였다. 해석 결과 고려된 활공 조건에서 구조 변형에 의한 공력 특성의 변화가 발생하는 것이 관측되었으며, 이에 의한 진동도 계속적으로 발생되는 것으로 표현되었다.

• 한국실내디자인학회논문집
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• 제22권2호
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• pp.81-88
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• 2013

Foundation Beyeler museum located near Basel, Switzerland is one of the most-visited art museum of the world. Although the entire volume of the museum is not huge, its art collection as well as the well-known museum building designed by Renzo Piano deserve to attract many visitors. The initial design was started in 1991 when the city of Basel decided to fund and support the project. Through a couple of design stages, the museum was finally opened to public in 1997. There have been various research papers dealt with general design issues of Beyeler museum such as composition of exhibition spaces, and natural lighting. However, this paper aims to study the design methods and relationship between art, architecture and nature. Although the museum building is located on the site quietly, there are various specific design solutions to create unique spatial experience of art and nature at each parts. This study focuses on 4 parts of the museum that are located on the main circulation. How art, architecture and nature are integrated together is the main target of the analysis. The analysis is based on visual-perceptual experience and spatial configuration. In chapter 2, general background of the project was studied. In chapter 3, characteristics of the site's natural environment and Piano's design concept's were examined. In chapter 4, each parts were analyzed in detail with diagrams. In chapter 5 & 6, the spatial characteristics were compared together and the fundamental role of the museum architecture was concluded.

• 대기
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• 제23권1호
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• pp.1-11
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• 2013

The angular momentum transport of an idealized axisymmetric vortex in the developing stage was investigated using the Weather Research and Forecast (WRF) model. The balanced axisymmetric vortex was constructed based on an empirical function for tangential wind, and the temperature, geopotential, and surface pressure were obtained from the balanced equation. The numerical simulation was carried out for 6 days on the f-plane with the Sea Surface Temperature (SST) set as constant. The weak vortex at initial time was intensified with time, and reached the strength of tropical cyclone in a couple of days. The Absolute Angular Momentum (AAM) was transported along with the secondary circulation of the vortex. Total AAM integrated over a cylinder of radius of 2000 km decreased with simulation time, but total kinetic energy increased rapidly. From the budget analysis, it was found that the surface friction is mainly responsible for the decrease of total AAM. Also, contribution of the surface friction to the AAM loss was about 90% while that of horizontal advection was as small as 8%. The trajectory of neutral numerical tracers following the secondary circulation was presented for the Lagrangian viewpoint of the transports of absolute angular momentum. From the analysis using the trajectory of tracers it was found that the air parcel was under the influence of the surface friction continuously until it leaves the boundary layer near the core. Then the air parcel with reduced amount of angular momentum compared to its original amount was transported from boundary layer to upper level of the vortex and contributed to form the anti-cyclone. These results suggest that the tropical cyclone loses angular momentum as it develops, which is due to the dissipation of angular momentum by the surface friction.

• Computers and Concrete
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• 제7권4호
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• pp.347-364
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• 2010

Since its invention in the $19^{th}$ century, Reinforced Concrete (RC) has been widely used in the construction of a lot of different structures, as buildings, bridges, nuclear central plants, or even ships. The details of the mechanical response for this kind of structures depends directly upon the material behavior of each component: concrete and steel, as well as their interaction through the bond-slip, which makes a rigorous engineering analysis of RC structures quite complicated. Consequently, the practical calculation of RC structures is done by adopting a lot of simplifications and hypotheses validated in the elastic range. Nevertheless, as soon as any RC structural element is working in the inelastic range, it is possible to obtain the numerical prediction of its realistic behavior only through the use of non linear analysis. The aim of this work is to develop a new kind of Finite Element: the "Enhanced Solid Element (ESE)" which takes into account the complex composition of reinforced concrete, being able to handle each dissipative material behavior and their different deformations, and on the other hand, conserving a simplified shape for engineering applications. Based on the recent XFEM developments, we introduce the concept of nodal enrichment to represent kinematics of steel rebars as well as bonding. This enrichment allows to reproduce the strain incompatibility between concrete and steel that occurs because of the bond degradation and slip. This formulation was tested with a couple of simple examples and compared to the results obtained from other standard formulations.

• Clinical and Experimental Reproductive Medicine
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• 제39권4호
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• pp.161-165
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• 2012

Objective: To evaluate the effect of hysterosalpingo-contrast sonography (HyCoSy) on natural conception in the infertile patient. Methods: We conducted a prospective observational study recruiting 180 patients admitted to Infertility Center of Ferrara University from January 2010 to February 2012. The essential inclusion criteria was the couple's desire to perform only diagnostic evaluation on infertility causes and to wait for natural conception before proceeding with further management. Couples were investigated with hormonal profile, semen analysis and HyCoSy. Expected time for spontaneous pregnancy was 180 days from HyCoSy. First datation sonography of pregnancy was used calculating time elapsed from HyCoSy at conception. Results: Forty patients (22.2%) obtained spontaneous pregnancy within 6 months after HyCoSy. The mean of "conception time" was 75 days. The pregnancy rate was significantly higher in the first 30 days (45%) compared to other the months of observation (p<0.0005). Multiple linear regression analysis showed that maternal age and sterility duration proved independent variables in detecting the "conception time" after HyCoSy (t=3.742, p=0.001, t=2.371, p=0.02, respectively). Conclusion: A possible beneficial effect of HyCoSy is feasible especially in the days following its execution. This temporal correlation supports its therapeutic use.

• 한국콘텐츠학회논문지
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• 제15권9호
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• pp.184-194
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• 2015

본 연구는 S사이버대학교 재학생 중 사회복지학 전공과목을 수강하고 있는 기혼 성인남녀 249명을 대상으로 원가족경험을 포함하여 현재 가족건강성에 영향을 미치는 요인을 분석한 것이다. 분석결과 기혼 성인남녀의 가족건강성은 5점 척도 기준으로 3.86정도로 중상수준이었고, 결혼상태, 종교, 소득, 경제문제, 부부문제, 고부/장서갈등, 자녀문제, 원가족경험이 가족건강성과 관련있는 것으로 나타났다. 단계적 회귀분석 결과 원가족경험의 하위요인인 전반적인 건강성, 갈등해소, 분리와 상실의 수용, 다른 가족원에 대한 허용성, 가족의 화목, 공동체의식, 확대가족내의 독립성, 가족의 공평성 중에서 공동체의식, 가족화목 요인이 현재 가족건강성에 영향을 주는 변수로 파악되었다. 이러한 결과는 한국의 가족주의 특성과 관련있는 것으로 생각되며, 가족간의 화목과 융화를 중시하는 전통 가치가 세대를 통해 가족건강성에 영향을 주고 있음을 시사한다.

• 터널과지하공간
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• 제21권2호
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• pp.128-137
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• 2011

수직 시추공에 대한 일반적인 수압파쇄시험으로부터 구해지는 균열폐쇄압력은 암반의 최소수평주응력을 직접 나타내기 때문에 현지암반의 응력분포양상을 해석하는데 있어서 매우 중요한 요소이다. 그러나 수압파쇄균열의 거동과 현지암반의 응력분포양상의 관계로 인하여 대부분의 경우 이 균열폐쇄압력은 수압파쇄 압력이력곡선 상에서 애매모호한 값으로 나타난다. 본 연구에서는 수압파쇄시험으로부터 균열폐쇄압력을 산정하기 위하여 여러 연구자들에 의해 제안된 기법들의 특성을 비교해 보고자 수치해석을 실시하였다. 즉, 유체의 가압에 의한 암반 내 균열의 발생이라는 수압파쇄의 특성을 모사하기 위하여 H-M couple 해석을 적용하였으며, 또한 수치해석 모델의 형상학적 특성에 따른 균열의 전파양상을 검토하기 위해 4가지 서로 다른 형태의 요소망을 구축하여 해석을 실시하였다. 각각의 요소망에 대한 수치해석 결과, 그래픽 방법이 통계적 방법에 비해 상대적으로 낮은 수준의 균열폐쇄압력을 보였으며, 따라서 시험공 주변에서의 응력 이상대의 존재 및 복잡한 메커니즘을 수반하는 수압파쇄균열의 발생양상을 감안할 때 수압파쇄시험에 의한 균열폐쇄압력의 산정시 특별한 주의가 요구된다.

• 가정과삶의질연구
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• 제31권5호
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• pp.47-63
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• 2013

This study deals with a counseling case in which a mother requested counseling due to the problems of her daughter, who suffers from multiple tic disorder. The participants of this study included five family members (grandmother, father, mother and two female children) and a total of 23 sessions were held from September 2006 to December 2007. Additional counseling ($24^{th}$ counseling session) was conducted on April 1st, 2009. The data was based on recorded transcripts and notes from 24 family therapy sessions. The study used a constant comparative analysis, which uses matrix and network display as an analysis method suggested by Miles&Huberman(1994). The characteristics of the family of origin and the indifference of the husband had caused the wife stress. The couple had frequent conflicts due to dysfunctional communication methods, a clash of values, sexual dissatisfaction, and a lack of communication. This marital conflict became the primary factor of the daughter's multiple tic disorder. Intervention of the family therapist resulted in the setting of treatment goals based on MRI's communication theory and Bowen's family systems theory in order to solve the problem of the daughter's multiple tic disorder. Also, the therapist's intervention techniques included exploring experiences with the family of origin, shedding light on the multigenerational transmission process, exploring dysfunctional attempts at solutions, the therapist's self-disclosure, providing similar cases, dealing with resistance, and suggesting a new communication method. To solve the problem, the therapist helped the family separate the daughter spatially from her parents. Therefore, the therapist's intervention helped reduce the daughter's tics and improve relationships among the family.

• 대한의료기공학회지
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• 제11권1호
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• pp.284-325
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• 2009

This study aims to investigate the educational significance in modern education by analysis on the contents of taboo in the Korean traditional prenatal education. For this study, the concrete matters are prepared for investigation as follows: First, the contents of prenatal education are analyzed with special reference to the Chinese bibliography and the Korean bibliography related to its own traditional prenatal education. Second, the contents of taboo in prenatal education are broadly classified into Chun-ki(天忌), Chi-ki(地忌), and In-ki(人忌), and in turn, In-ki is classified into taboo related to clothing, taboo related to food, Taboo related to housing, and man's taboo, and all of them are interpreted. Third, the characteristics of taboo in the Korean traditional prenatal education and its principle are analyzed, and its significance is researched from the modern educational point of view. This study attempts to classify the contents of taboo into Chun-ki, Chi-ki, In-ki, and man's taboo based upon analysis of the documentary records related to the traditionary prenatal education in China and Korea for the successful investigation. The characteristic such as common discipline, the time limit and prevention are induced on the basis of this investigation, and its modern educational significance as follows: First, prenatal education must be conduced as a part of youth education and preparatory parents education for the married couple. Second, man or husband plays a very important role of practising taboo in prenatal education. Third, taboo in prenatal education is very suggestive in the aspect of human relationship and mental health of the pregnant woman. Fourth, it prevents her obesity and strain. Fifth, the scientific proof and education of taboo related to food must be needed.