• Title/Summary/Keyword: ideal boundary

검색결과 131건 처리시간 0.024초

자동차용 열전지에서 유로배열 효과 예측을 위한 열유동 수치묘사 (A Numerical Simulation of Heat and Fluid Flow for Predicting the Effect of Passage Arrangement in Automotive Heat Battery)

  • 이관수;권재웅;백창인;송영길;한창섭;김동진
    • 한국자동차공학회논문집
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    • 제3권5호
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    • pp.64-73
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    • 1995
  • A numerical simulation of heat and fluid flow for predicting the effect of passage arrangement in automotive heat battery has been performed. The system is assumed to be a two-dimensional laminar flow and isothermal boundary is applied to the surface of the latent heat storage vessel. In the case of ideal heat battery the flow rate into each flow passage is evenly distributed. The various models are considered in the view of pressure drop and bulk temperature. The effects on the efficiency of the heat battery are examined by varying geometrical factors such as flow passage clearance, length of a inlet and outlet tank and the length of a latent heat storage vessel. The flow clearance is a very important -factor on the efficiency of a heat battery. As the flow passage clearance becomes narrow, the flow distribution becomes uniform and the bulk temperature increases, however the pressure drop is large. Therefore, optimal flow passage clearance has to be chosen. The present work can be used in optimizing heat battery efficiency.

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The Differential Effect of Emotional Labour on Boundary Spanners

  • MUPARANGI, Simbarashe;SIZIBA, Singirai;MAKUDZA, Forbes
    • 웰빙융합연구
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    • 제4권1호
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    • pp.1-10
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    • 2021
  • Purpose: The study sought to uncover the effect of emotional labour strategies (surface acting and deep acting) on job satisfaction and emotional exhaustion. The study also purposed to analyse the moderating effect of organisational support (supervisory support and co-worker support) and the role of gender on emotional labour connotations. Research design, data and methodology: A conceptual framework was developed using extant literature which led to the examination of deep acting and surface acting, which are the two main strategies of emotional labour. The outcome variables were emotional exhaustion and job satisfaction. Data was collected from front line employees of banks and was analysed using SEM-AMOS version 21. Results: It was revealed, in this study, that surface acting is inversely related to job satisfaction and positively related to emotional exhaustion, whereas deep acting was positively related to job satisfaction and inversely related to emotional exhaustion. The roles of gender and organisational support were also confirmed. Conclusions: The study therefore concluded that deep acting is the most ideal strategy of emotional labour as it leads to job satisfaction and reduced emotional exhaustion. Surface acting is a harmful emotional labour strategy.

전문대학생이 체험한 사회복지실습의 의미 탐색 (The Meaning on Social Work Practicum that College Students Have Experienced)

  • 신현정
    • 한국사회복지학
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    • 제68권4호
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    • pp.169-198
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    • 2016
  • 본 연구는 전문대학생이 체험한 사회복지실습의 상황적 맥락과 의미를 아는데 목적을 둔다. 전문대 학생의 사례를 중심으로 현상학적 방법을 활용해 자유변경(free variation)에 입각한 사회복지실습의 본질을 찾고자 했다. 전문대학 생의 사회복지실습체험의 맥락은 실습지 선정부터 '높은 장벽'을 만났다. 그 속에는 무엇을 해야 하는지 '경계가 모호한 업무와 역할'이 많았다. 실습 일상에서의 '딜레마적 상황'이 실습생에게 혼란을 일으켰다. 관찰과 학습, 참여는 실습생에게 '사회복지(사)에 대한 애상'을 갖게 했고 더 나은 사회복지(사)로의 탈존(ex-ist)에 대해 생각하도록 했다. '다양한 가능태로서의 분주한 장(場)'은 실습생에게 '빈약한 몸이지만 멀티플레이어'로서의 역할을 가능하게 했다. 다양한 공간과 장소 속에서 실습생은 사회복지를 넘어선 자신의 능력과 실체에 대한 '현실 직면의 시간'을 맞는다. 그리고 그 시간은 자신의 과거, 현재, 미래, 타자와의 관계 등을 평가하는 상황 속에서 연계된다. 논의는 네 가지로 구성된다. 첫째, 실습생들은 실습을 통해 사회복지사의 위상과 현실을 확인하였다. 이에 따른 직업정체성의 고민도 수반되었다. 둘째, 실습지의 고유성을 인정하되 실습지도의 체계성을 재고해야 한다. 셋째, 자원봉사의 활성화 등 실습에 대한 이상적 개념과 현실적 상황 간 간극을 좁힐 수 있는 방안이 필요하다. 넷째, 직무와 기능 향상을 초월하는 학교교육의 방향설정이 필요하다.

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고속처리 자동차 번호판 인식시스템 (A High Performance License Plate Recognition System)

  • 남기환;배철수
    • 한국정보통신학회논문지
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    • 제6권8호
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    • pp.1352-1357
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    • 2002
  • 본 논문에서는 차량의 후면에서 촬영한 영상을 이용하여 효과적으로 번호판을 추출하고, 그 안에 표기된 문자를 인식하는 방법을 제안한다. 기존의 연구방법은 전체영상에 대하여 전처리를 수행하여 에지(edge)영상을 구하여 이진화한다. 이진화된 영상에서 허프(Hough)변환을 수행하여 수평, 수직선을 구하고, 번호판의 특징을 이용하여 번호판 영역을 추출한다 이 방법의 문제점은 처리시간이 많이 소요되므로 실시간 처리가 곤란하다는 점과 야간관 같이 명암상태가 불규칙하고 영상에서 번호판 테두리가 나타나지 않으면 번호판 영역추출을 할 수 없다는 점이다. 또한 차량의 후면에서 촬영한 영상에서 번호판 영역의 명암값 변화의 특성을 이용하여 번호판 영역에서 숫자폭, 배경영역과 숫자영역의 명암차를 조사하여 숫자영역임을 확인하고, 확인된 숫자와 숫자사이의 거리를 조사하여 번호판 영역을 추출한다. 본 연구는 기존방법의 번호판 테두리 훼손에 따른 번호판 영역추출 실패의 문제점을 해결하고 시간 소요의 문제를 실시간 안에 처리함으로써 실용적 응용이 가능하다. 실험 결과 100장의 샘플영상으로 실험한 결과 멀리 있는 자동차 영상에서도 자동으로 번호판을 판독할 수 있었으며, 번호판 추출에 실패한 영상은 13%를 나타내었고, 문자 인식에 실패한 영상은 0.4%의 결과를 나타내었다

직상류 계측유량경계조건과 분포형모델을 이용한 대규모 다목적댐 홍수유입량 산정 (Flood Inflow Estimation at Large Multipurpose Dam using Distributed Model with Measured Flow Boundary Condition at Direct Upstream Channels)

  • 홍석현;강부식
    • 대한토목학회논문집
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    • 제35권5호
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    • pp.1039-1049
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    • 2015
  • 대규모 다목적댐 지점의 유입량 산정은 수위-저수용량곡선에 댐 축에서 측정된 수위를 적용하여 시간당 저수량변화를 계산한 후 방류량을 감안하여 산정하고 있으나, 이 방법은 태풍 등 대규모 홍수 시에는 급격한 유입량 증가로 인한 배수위 및 강한 바람 등의 영향으로 저수지내의 수위가 균일하지 않아 유입량 산정 시 오차 원인이 되고 있다. 이 외에 기존 수위-저수용량 곡선 방법에 의한 유입량 계산 시 문제점인 댐건설 이후 유입 퇴사로 인한 저수용량의 변화, 댐 지점에서의 수위관측의 불균일성 등 다양한 불확실성이 존재하므로 이에 대한 오차 규명이 반드시 필요하다. 본 연구에서는 저수지 유입량 분석시 분포형 강우유출모형을 이용한 UBC-3P 기법을 적용하여 모형의 모의능력을 평가하였다. 최종적으로 기존 유역내 유입량 관측치와 비교한 결과 Peak유량과 Total유량에서 결정계수가 0.82~0.99 사이값을 나타내므로 댐 지점에서의 모형의 적합성을 확인하였다.

지오폰을 활용한 현장 위상각차 계측 데이터 신뢰 구간에 관한 기초 연구 (Study of Confidence Ranges for Field Phase Difference Measurement Data Collected using Geophones)

  • 김건웅
    • 한국지반공학회논문집
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    • 제40권3호
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    • pp.41-54
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    • 2024
  • 건설된 지반구조물을 안전하게 유지하기 위해 정기적인 모니터링은 매우 중요하다. 현재 유지관리를 위해 센서를 기반으로 하는 가속도, 변위계, 이미지를 기반으로 하는 레이저 혹은 드론 영상 촬영 등 지반구조물에 영향을 최소화할 수 있는 비파괴방식이 활용되고 있다. 해당 기술들은 표면의 변화를 관찰할 수 있지만, 내부 물성값 변화 파악에는 어려움이 있다. 지반구조물의 내부 물성값 변화를 모니터링하기 위해 현장 지반조사법이 도입될 수 있으며, 이를 위해 활용될 수 있는 비파괴시험에는 지오폰을 활용한 Spectral-Anlysis-of-Surface-Wave(SASW) 시험이 있다. SASW 시험은 비파괴시험이지만, 데이터 해석에 드는 시간과 분석에 어려움으로 인해 잦은 관찰을 요구하는 유지관리 모니터링의 용도로 활용이 어렵다. 하지만, 전단파 속도를 도출하는 복잡한 SASW 최종 해석이 아닌 분산곡선을 도출하는 1단계 해석만으로도 모니터링에 적용할 수 있다. 따라서, 본 논문에서는 SASW 시험을 모니터링에 활용하기 위해 분산곡선 도출에 필요한 위상각차 데이터에 관한 기초 연구를 수행하였다. 위상각차 구간별 신뢰도에 대해 검토하여 데이터 모니터링에 활용이 가능한 범위에 관하여 확인하였다. 이를 위해 단일 층으로 구성된 균질한 지반 현장에서 지오폰을 활용하여 계측한 위상각차 데이터들을 활용하였다. 본 연구를 통해 활용할 수 있는 위상각차 데이터 구간을 파악해 모니터링의 활용성을 높일 것으로 기대된다.

Is Sorting Hat in Harry Potter Identity Identifier for Adolescents?

  • Bahn, Geon Ho;Sun, Je Young Hannah;Hwangbo, Ram;Hong, Minha;Park, Jin Cheol;Cho, Seong Woo
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제28권1호
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    • pp.38-43
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    • 2017
  • This study analyzes the role of the Sorting Hat in structuring the identity of the characters in the Harry Potter series written by J. K. Rowling. In the different stages of adolescence, one explores and re-establishes one's identity. One's sense of identity is determined by the commitments made regarding personal and social traits. However, it is difficult to establish a concrete identity formation process theory that is communicable to adolescents. In Harry Potter, the characters' identities are reflected upon the Sorting Hat and are continuously molded throughout the book. The Sorting Hat provides nurturing experiences based on temperament. Based primarily on their temperament, it sorts the students into four houses, each with their own distinct characteristics. Once sorted, the houses become the living and learning communities in which the students share the same dormitory and classes until their graduation. Within the community, the students seek connections, supportive relationships, and understanding within the group. The taking on of the group identity is an explanatory variable in the formation of individual identity. The Sorting Hat provides the students with stability and a safe boundary. After being sorted based on their temperament, the inexperienced and immature adolescents can explore different options under the guidance of the Hat before making a definite commitment. By presenting them with an appropriate environment (such as a mentor, friend, or family member), the Hat further shapes their identity and integrates the identity elements ascribed in the beginning. By providing experiences and interactions based on their unique temperament and environment, the Sorting Hat plays a crucial role in establishing the students' identities. The Sorting Hat can be an ideal model for finding one's identity during adolescence.

Effects of interface delay in real-time dynamic substructuring tests on a cable for cable-stayed bridge

  • Marsico, Maria Rosaria
    • Smart Structures and Systems
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    • 제14권6호
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    • pp.1173-1196
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    • 2014
  • Real-time dynamic substructuring tests have been conducted on a cable-deck system. The cable is representative of a full scale cable for a cable-stayed bridge and it interacts with a deck, numerically modelled as a single-degree-of-freedom system. The purpose of exciting the inclined cable at the bottom is to identify its nonlinear dynamics and to mark the stability boundary of the semi-trivial solution. The latter physically corresponds to the point at which the cable starts to have an out-of-plane response when both input and previous response were in-plane. The numerical and the physical parts of the system interact through a transfer system, which is an actuator, and the input signal generated by the numerical model is assumed to interact instantaneously with the system. However, only an ideal system manifests a perfect correspondence between the desired signal and the applied signal. In fact, the transfer system introduces into the desired input signal a delay, which considerably affects the feedback force that, in turn, is processed to generate a new input. The effectiveness of the control algorithm is measured by using the synchronization technique, while the online adaptive forward prediction algorithm is used to compensate for the delay error, which is present in the performed tests. The response of the cable interacting with the deck has been experimentally observed, both in the presence of delay and when delay is compensated for, and it has been compared with the analytical model. The effects of the interface delay in real-time dynamic substructuring tests conducted on the cable-deck system are extensively discussed.

해양파(海洋波)의 운동학(運動學)에 대한 중력파이론(重力波理論)과 Steam Function Method의 비교연구(比較硏究) (A Study on the Kinematics of Ocean Waves by Gravity Wave Theory and Stream Function Method)

  • 방윤규;장인화;최항순
    • 대한조선학회지
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    • 제19권2호
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    • pp.33-39
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    • 1982
  • It is one of the basic problems of naval architecture and ocean engineering how to describe the wave kinematics normally under the assumption of an ideal fluid. At present, there are many wave theories available for design purposes. These can be classified into two groups: One is the analytic theory and the other is the numerical theory. This paper briefly introduces the stream function method of R.G. Dean which belongs to the latter group and shows its numerical evaluations exemplified for two cases: One is applied to observed waves and the other is for design waves. In the former case, the wave profiles are calculated by the stream function method and compared with those of the observed waves and also with the results of R.G. Dean. They show good agreement. In the latter case, the wave kinematics and wave loads on a column of diameter 1m are calculated by the stream function method and these are compared with those resulted from the 5th-order gravity wave theory. As a result of comparison the values by the stream function method are slightly larger than those by the 5th-order gravity wave theory but the difference are negligible. From this it is concluded that the stream function method is very useful. And as characteristics of the numerical theories, the stream function method of R.G. Dean can be easily extended to the higher order terms and can include easily the current velocity and the pressure distribution on the free surface. In addition, when the data of observed wave profile are given, this method can reproduced the observed wave profile as closely as possible so that this method seems to describe the ocean wave more realistically. And from standpoint of a mathematical principle the stream function method exactly satisfies the kinematic free-surface boundary condition.

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퍼스널 이미지 메이킹을 위한 패션 연출에 관한 연구 (A Study on the Fashion Styling for Personal Image Making)

  • 최영선;최현숙
    • 한국의류산업학회지
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    • 제9권1호
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    • pp.49-54
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    • 2007
  • In the 21th century, the age of image, people express and evaluate with images. Image is a symbol of a person or a thing. It simulates people's visual sense most quickly and precisely and is shared in the society. At the time, since it is acknowledged that there are few books available and lack of theoretical system with regard to image making, the purpose of this study was to get a theoretical access to image making by taking as an empirical case the case of Choi Byeongryeol, a candidate running for the congress in June 4, 1998 and combining it with theories of costume. Research methods employed here were to investigate the theoretical system of image making and fashion direction, and to analyze empirical cases. The boundary of the empirical case was limited to the candidate's fashion direction during the election period for 50 days from April 1998 to the election date June 4, 1998. The results of this study are as follows. First, personal image making aims at the establishment of one's own identity through building up an ideal image. Second, it is found that personal image making can make a complete image possible through fashion direction. Third, it is found that fashion direction functions as a symbol and communicative means with a result that the effect can penetrate to the society accurately and quickly. Fourth, it is found that fashion direction fit for a situation can enhance personal values and reinforce his or her competitive power to carry out the ultimate goals in the society. This study proved that fashion styling for personal image making expresses a person in a symbolic image, enhances his/her personal value in the society and, ultimately, contributes to the establishment of an individual's identity.