• 제목/요약/키워드: 역작용

검색결과 1,083건 처리시간 0.026초

An Interfacial Crack Model with Inclined Strip Plastic Zones under Mode III Load (모우드 III 하중 하에서 경사진 띠모양의 소성역을 가정한 계면균열 모델)

  • 박재학;엄윤용
    • Transactions of the Korean Society of Mechanical Engineers
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    • 제13권2호
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    • pp.243-251
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    • 1989
  • Assuming plastic zones spreading out on each slip plane of the two materials under out-of-plane shear loading, the size of each plastic zone is computed. The effect of the different frictional shear stresses in the two materials on the size of each plastic zone and the relative displacement at the crack tip are investigated. The relation between the J-integral in this model and the relative displacement at the crack tip is also obtained.

A Study on Analysis of Types and Roles of Records Management & Archives Professionals Abroad (국외 기록관리 전문직 유형 및 역할 분석 연구)

  • Kim, Heejung
    • Journal of Korean Society of Archives and Records Management
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    • 제7권1호
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    • pp.129-143
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    • 2007
  • In this study, various types and roles of records management and archives professionals are reviewed. Throughout the literature review, types and roles of the records management and archives professionals are analyzed. The results show that roles of professionals can be divided into the areas of records, users and management. In addition to focusing on records and archives, modern archival professionals must also be adept in such areas as knowledge management and digital asset management. Business and management skills for forging partership with related organizations are also needed.

Constructing 3-year-old classroom with role play areas based on field-trips (현장학습을 중심으로 구성해가는 만 3세 교실의 역할 놀이 영역)

  • Suh, Hye Jeong;Han, Ye Hee
    • Korean Journal of Childcare and Education
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    • 제6권2호
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    • pp.83-115
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    • 2010
  • The purpose of this study is to reveal the insights that teachers has learned through developing preschooler's classroom into field-trip-oriented ones with role play areas. The data of this study was collected from participatory observation and in-depth interviews, which included videos, photos, teachers' journal, descriptive questionnaire, and interview records. The whole process of organizing role-play oriented class was composed of four steps: activities before the trip, activities on-the-spot, activities after the trip, and its evaluation. Firstly, activities before the trip were making the lists of questions, deciding children who ask the questions, making rules on the trip, understanding the purpose of the trip. Secondly, on-the-spot activities included having a tour of the place and asking the questions. Thirdly, activities after the trip was constructing the classroom into small real world with various sections. This required the teachers to reflect the field trips, make plans how to construct, prepare for the data, and furnish the classroom with role-play areas. In the process of furnishing the classroom with small real world, the field trips played a big role as the learning opportunities for language development, and keeping public rules.

Implementation and Design of Wideband IFIU using Aperture Open Loop Resonator and Reversed Phase Technique (역 위상 기법과 Aperture를 갖는 개방형 루프 공진기를 사용한 광대역 IF 모듈 설계 및 제작)

  • 김영완
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • 제41권11호
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    • pp.17-23
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    • 2004
  • The implementation and design of the wideband IFIU using aperture open loop resonator and reversed phase technique to reduce the local oscillator leakage signal was represented in this paper. The local oscillator leakage signal is generated in stage of frequency conversion, especially in frequency conversion of fully digital modulation signal close to DC signal. The leakage signal and spurious signals, which have effects on adjacent channel or in-band channel as interference signals, were reduced below -60 dBc for 45 Mbps and 155 Mbps IF interface units. The group delay for both IFIUs shows low ripple characteristics of 15 ns and 8 ns, respectively. Also, the amplitude ripple characteristic in 150 MHz bandwidth with L-band center frequency satisfies the required specification of 2 dB. The implemented IFIU provides the required specifications for wideband satellite communication system.

Credit Card Interest Rate with Imperfect Information (불완전 정보와 신용카드 이자율)

  • Song, Soo-Young
    • The Korean Journal of Financial Management
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    • 제22권2호
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    • pp.213-226
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    • 2005
  • Adverse selection is a heavily scrutinized subject within the financial intermediary industry. Consensus is reached regarding its effect on the loan interest rate. Despite the similar features of financial service offered by the credit card, we still have controversy regarding credit card interest rate on how is adverse selection incurred with the change of interest rate. Thus, this paper explores how does the adverse selection, if ever, take place and affect the credit card interest rate. Information asymmetry regarding the credit card users' type represented by the default probability is assumed. The users are assumed to be rational in that they want to minimize the per unit dollar expense associated with the commercial transaction and financing between the two typical payment methods, cash and credit card. Suppliers, i.e. credit card companies, would like to maximize their profit and would be better off with more pervasive use of credit cards over the cash. Then we could show that the increasing credit card interest rate is subject to the adverse selection, sharing the same tenet with that of the bank loan interest rate proposed by Stiglitz and Weiss. Hence the current theory predicts that credit card market also suffers from adverse selection with increasing interest rate.

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Exploring interaction using 3-D residual plots in logistic regression model (3차원 잔차산점도를 이용한 로지스틱회귀모형에서 교호작용의 탐색)

  • Kahng, Myung-Wook
    • Journal of the Korean Data and Information Science Society
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    • 제25권1호
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    • pp.177-185
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    • 2014
  • Under bivariate normal distribution assumptions, the interaction and quadratic terms are needed in the logistic regression model with two predictors. However, depending on the correlation coefficient and the variances of two conditional distributions, the interaction and quadratic terms may not be necessary. Although the need for these terms can be determined by comparing the two scatter plots, it is not as useful for interaction terms. We explore the structure and usefulness of the 3-D residual plot as a tool for dealing with interaction in logistic regression models. If predictors have an interaction effect, a 3-D residual plot can show the effect. This is illustrated by simulated and real data.

Theoretical Considerations on Analytical Framework Design for the Interactions between Participants in Group Argumentation on Socio-Scientific Issues (사회 속 과학 쟁점에 대한 소집단 논변 상호작용 분석을 위한 방법론 고찰)

  • Park, Jee-Young;Kim, Heui-Baik
    • Journal of The Korean Association For Science Education
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    • 제32권4호
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    • pp.604-624
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    • 2012
  • This study aims to design a framework for analyzing group argumentation in terms of participants' interaction. Regarding the current group argumentation setting as argumentation on socio-scientific issues within participants who have had limited experience on group argumentation, the analytical framework was designed to explain (1) what was each participant's role on group argumentation, (2) how these roles were changed within each time of argumentation, and (3) how the patterns of interaction were changed through seven times of a series of argumentation on socio-scientific issues. Based on the literature review on analytical framework of argumentation in science education including the works on the structure of argumentation, the discourse formation through interaction, and the linguistic approach on participants' interaction, the current research framework was built. Showing the results of applying the designed framework on group argumentation as an example, strength of using the current designed framework was discussed.

Evaluating Method of Solitary Wave-Induced Tsunami Force Acting on an Onshore Bridge in Coastal Area (연안역의 육상 교량에 작용하는 고립파에 의한 지진해일파력의 평가법)

  • Kim, Do-Sam;Kyung, Kab-Soo;Lee, Yoon-Doo;Woo, Kyung Hwan
    • Journal of the Computational Structural Engineering Institute of Korea
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    • 제29권2호
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    • pp.149-159
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    • 2016
  • In this study, the solitary wave-induced tsunami force acting on an onshore bridges in coastal area was numerically modelled by means of TWOPM-3D based on Navier-Stokes solver and VOF method which can track free surface effectively. The validity of numerical analysis was verified by comparing the experimental tsunami bore force acting on vertical wall and column structure. In particular, the characteristics of tsunami force with the changing tsunami intensity were surveyed through numerical experiments. The availability of 3-dimensional numerical analysis was reviewed through the comparison between the existing numerical results and design criteria for each drag force coefficient by applying Morison equation considering only drag force. As reasonable and high-precision estimation method of tsunami force, it was suggested to apply the estimation method taking drag and inertial force into consideration at the same time.

Characteristics of Interaction among Actors in Triple Helix of Cultural Contents Industry Cluster in Daegu (대구문화콘텐츠산업 클러스터에서 트리플 힐릭스 주체의 상호작용 특성)

  • Park, Kyung-Sook;Lee, Chul-Woo
    • Journal of the Korean association of regional geographers
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    • 제19권3호
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    • pp.401-415
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    • 2013
  • This study aims to examine the characteristics of interaction among innovative actors including industry, university and government, participating in cultural contents industry cluster in Daegu. Specifically, the study focuses on the change of role for each actor. Triple helix of cultural contents industry cluster in Daegu has been developed backed up by strong contribution of both industry and government, and by interaction between them. However, As technologies surrounding cultural contents industry become complicated and diversified, The role of the university as an entrepreneurial university is more important. In this sense, respective actors should strengthen its capacity in order to improve triple helix of cultural contents industry in Daegu. Based on this, government policy should be established and implemented toward to encouraging cooperation among participating actors.

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Calculation of Permanent Magnet Thickness for Single Phase LSPM Considering the Irreversible Demagnetization of Permanent Magnet (불가역 감자를 고려한 단상 LSPM의 영구자석 두께 산정)

  • Lee, Tae-Hoon;Lee, Jeong-Jong;Ryuh, Se-Hyun;Kim, Young-Kyoun;Jung, In-Soung
    • Proceedings of the KIEE Conference
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    • 대한전기학회 2011년도 제42회 하계학술대회
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    • pp.1007-1008
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    • 2011
  • LSPM(Line Start Permanent Motor)은 기존의 가정용으로 널리 사용되고 있는 단상유도기에 영구 자석을 삽입함으로써 별도의 회로 없이 정상상태에서 동기기로 작용하는 고효율의 전동기이다. 하지만 기동시 높은 전류로 인한 전기자 반작용과 온도 상승으로 인하여 자석의 불가역 감자가 빈번하게 일어나는 문제점을 가지고 있다. 이에 본 논문은 모터 형상에 따른 영구자석의 퍼미언스 계산을 통해 동작점을 산정함으로서 불가역 감자가 발생하지 않는 영구자석의 최적의 사이즈를 선정하는데 목적을 두었다.

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