• Title/Summary/Keyword: CLs

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Linear Buckling Analysis of Thin-walled Structures by Flat Shell Elements with Drilling D.O.F. (회전자유도를 갖는 평면쉘요소에 의한 박판구조물의 선형 좌굴해석)

  • 최창근;송명관
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.258-265
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    • 1998
  • Application of the flat shell element with drilling D.O.F to linear buckling analysis of thin-walled structures is presented in this paper. The shell element has been developed basically by combining a membrane element with drilling D.O.F. and Mindlin plate bending element. Thus, the shell element possesses six degrees-of-freedom per node which, in addition to improvement of the element behavior, permits an easy connection to other six degrees-of-freedom per node elements(CLS, Choi and Lee, 1995). Accordingly, structures like folded plate and stiffened shell structure, for which it is hard to find the analytical solutions, can be analyzed using these developed flat shell elements. In this paper, linear buckling analysis of thin-walled structures like folded plate structures using the shell elements(CLS) with drilling D.O.F. to be formulated and then fulfilled. Subsequently, buckling modes and the critical loads can be output. Finally. finite element solutions for linear buckling analysis of folded plate structures are compared with available analytic solutions and other researcher's results.

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Effect of Organic Admixture(Calcium Lignosulfonate) (I) on the Early Hydration Process of Protland Cement (시멘트 초기 수화과정에 대한 유기혼화제의 영향(I))

  • 문정연;최상홀
    • Journal of the Korean Ceramic Society
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    • v.21 no.2
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    • pp.143-148
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    • 1984
  • In this study we mainly dealt with the effects of organic retarder(calcium lignosulfate) on the early hydration process of clinker minerals. From a consideration of the hydration process of tricalcium silicate $(C_3S)$ tricalcium silicate $(C_3S)$-tricalcium aluminate $(C_3A)$ tricalcium silicate $(C_3S)$-tetracalcium aluminof-errite $(C_4AF)$ systems with calcium lignosulfate the following results were obtained. 1. when 0.25wt% of CLS was added to $C_3S$ the hydration process was progressed normally but adding of 0.5wt% its hydration was greatly retarded. 2. The hydration of $C_3S$-$C_3A$ system was progressed normally up to 0.5wt% but by adding gypsum its hydration was retarded slightly. 3. The hydration of $C_3S$-$C_4AF$ system was greatly retarded even with 0.25wt% of CLS but by adding gypsum its hydration process was recovered normally.

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Design and Implementation of a Class Pile Converter for Embedded Java Virtual Machine (내장형 자바가상기계를 위한 클래스 파일 변환기의 설계 및 구현)

  • 지정훈;양희재
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04a
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    • pp.67-69
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    • 2003
  • 자바는 서로 다른 종류의 컴퓨터 시스템에서 동일하게 동작하는 플랫폼 독립적인 특성을 가지고 있다. 자바가 상기계(JVM)는 클래스 파일을 읽어 들여 인터프리팅하여 실행한다. 보조기억장치가 없는 내장형 시스템에서는 메모리에 클래스 파일이 위치하는데 클래스 파일에는 디버깅등의 목적으로 사용하는 정보와 클래스, 상수, 필드, 메소드 둥의 정보들을 포함하고 있기 때문에 내장형 시스템에서 사용하기에 적합하지 않다. 본 논문에서는 클래스 파일을 변환하여 내장형 시스템에서 시스템의 효율적인 자원 사용과 성능을 향상시킬 수 있도록 클래스 파일을 변환 해주는 도구인 cls2bin을 설계 및 구현하였다. c1s2bin은 클래스 파일에서 동작에 필요하지 않은 정보들을 제거하고 인터프리팅 될 수 있는 새로운 이미지(bin) 파일을 생성한다 cls2bin의 동작과정과 bin 파일 포맷을 살펴봄으로서 내장형 시스템에서 효율적인 자원사용과 내부정보의 접근 방법을 고찰하였으며 그 결과로 내장형 자바 시스템에서의 개선된 클래스 파일의 형태를 정의하고자 한다.

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Effects of Ovarian Morphology and Culture Vessel on In vitro Development and Cell Number in Embryos of Korean Native Cows

  • Park, Yong-Soo;Kim, Jae-Myeoung
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.1
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    • pp.31-35
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    • 2007
  • The main purpose of this study was to improve the efficiency and quality of in vitro embryo production in Korean Native Cows (KNC). We examined the effects of ovarian morphologies (Experiment 1) and the culture vessel (Experiment 2) on in vitro maturation (IVM). We measured the subsequent development rates and cell numbers of blastocysts. In Experiment 1, the ovaries of KNC were divided into six groups, based on follicle and corpus luteum (CL) morphology. The development rates to the 2- and 8-cell stages were similar among the six groups. The development rates to blastocyst stages were significantly higher in the group without a CL or follicle (WOCL/F) than in the groups with follicular cysts (FCs), regressive CLs (RCLs) or cystic CLs (CCLs) (p<0.05). The cell number of the inner cell mass (ICM) of blastocysts in the FCs and RCLs groups, and the number of cells in the trophectoderm (TE) in the WOCL/F group, FCs, growing CLs (GCLs) and RCLs were significantly higher than in other groups (p<0.05). The total cell number (TCN) in the WOCL/F, FC and RCL groups was also significantly higher than in other groups (p<0.05). The ICM cell number/TCN ratio was significantly higher in the FC and RCL groups than in the GCL and DF groups (p<0.05). In Experiment 2, oocyte IVM was carried out in culture dishes, in 0.25- or 0.5-ml straws used for freezing sperm. The development rate to the 2-cell stage was significantly higher in the 0.5-ml straw group than in the 0.25-ml straw group. The development rates to the blastocyst stage were similar in the dish and the two straw groups. There were no differences in the cell numbers of ICM, TE or TCN or ICM cell number/TCN ratios between groups.

A Study on QTG(Qualification Test Guide) Generation for a Flight Training Device to be Qualifiable at FAA Level 5 (X-Plane 기반 비행훈련장치의 FAA Level 5 FTD(Flight Training Device) 인증을 위한 QTG(Qualification Test Guide) 생성방법 연구)

  • Kim, Il-Woo;Park, TaeJun;Yoon, SukJun
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.44 no.12
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    • pp.1035-1042
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    • 2016
  • By using commercial flight simulation game engine, X-Plane, we have studied QTG(Qualification Test Guide) generation that can satisfy FTD level 5. Flight model is SR-20 of Cirrus. In list of QTG, There are some items to measure control forces. therefore, we have installed CLS(Control Loading System) to flight control devices in order to make it possible to measure control forces. We made Autopilot function externally to make flight model in trim conditions because X-Plane don't provide internal trim routine function. In addition to develop an algorithm, it can automatically perform the test. To avoid the inconvenience to control as it was to be carried out in same conditions. In case of FTD level 5, it is possible to use alternative data sources not only real flight data. By using these alternative data sources, all test results satisfy a scope given by CFR Part 60.

Development of Reversing the Usual Order of Somatic Cell Nuclear Transfer in Mice

  • Kang, Ho-In;Sung, Ji-Hye;Roh, Sang-Ho
    • Journal of Embryo Transfer
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    • v.26 no.1
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    • pp.85-89
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    • 2011
  • Somatic cell nuclear transfer (SCNT) is a useful tool for reproducing genetically identical animals or producing transgenic animals. Many reports have demonstrated that the efficiency of animal cloning by SCNT requires reprogramming of the somatic nucleus to a totipotent like-state. The SCNT-related reprogramming might mimic the natural reprogramming process that occurs during normal mammalian development. However, recent evidence indicates that the reprogramming event by SCNT is incomplete. In this study, the traditional SCNT procedure (TNT) was modified by injecting donor nuclei into recipient cytoplasm prior to the enucleation process to expose the donor nucleus before removing the karyoplast containing the chromosomes of the oocytes which might possess additional reprogramming factors, and this modified technique was named as reversing the usual order of SCNT (RONT). Other procedures including activation and in vitro culture were the same as TNT. Contrary to expectations, the rate of blastocyst development was not different significantly between RONT and TNT (8.6% and 7.9%, respectively). However, duration of micromanipulation performed by the same technician and equipments was remarkably reduced because the ruptured oocytes after nuclear injection were excluded from the enucleation process. This study suggests that RONT, a simplified SCNT protocol, shortens the duration of SCNT procedure and this less time-costing protocol may enable the researchers to perform murine SCNT easier.

Research on the Design and Evaluation of a Control Loading System for Flight Simulator (비행 시뮬레이터용 조종력 재현 장치 설계 및 시험연구)

  • Lee, Chan-Seok;Kim, Byoung-Soo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.4
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    • pp.95-100
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    • 2004
  • This paper represents the development of a CLS(Control Loading System) for a target a airplane (KT-1) with mechanical linkage reversible flight control system. The system is composed of mechanical frame, controller, sensing part to measure the force from the stick, driving system generating the reaction forces. The DS1103 DSP(Digital Signal Processor) of the dSpace Corp. was used as the controller. The control algorithm of the CLS and the operational environment including monitoring software and evaluation tools are described. The evaluation of the system was conducted according to the requirement specification. The results of the test were analyzed by comparing with the actual data of the target airplane.

Development of Clinical Ladder System Model for Nurses: For Tertiary Care Hospitals (간호사 임상경력관리체계 모형 개발 - 상급종합병원 중심 -)

  • Cho, Myung Sook;Cho, Yong Ae;Kim, Kyung Hee;Kwon, In Gak;Kim, Mee Soon;Lee, Jung Lim
    • Journal of Korean Clinical Nursing Research
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    • v.21 no.3
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    • pp.277-292
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    • 2015
  • Purpose: The purpose of this study was to develop a Clinical Ladder System (CLS) model for staff nurses working in inpatient units of tertiary care hospitals in Korea. Methods: The study was carried out in 2 steps. First, a nursing competence evaluation scale was developed. Second, evaluation of the nursing competences, qualifications, and professional activities of 230 nurses from five tertiary care hospitals was done by 49 head nurses between Feb. and Dec., 2014. Nurses were selected by head nurses according to their clinical experience and expected behavioral characteristics at each level of the ladder. Results: A nursing competence scale was developed consisting of 5 subcategories (clinical practice, ethical practice, education, leadership, and professional development) and 11 elements, and 5 levels of behavioral indicators for each element. Cronbach's alphas for the entire tool and subcategories were over .853 and stability of the scale was confirmed. There were significant differences in nursing competence according to the 5 levels of the ladder. Conclusion: The findings indicate that the proposed CLS model with a standard score for nursing competence, recommended or obligatory criteria for qualifications and professional activities provides a good tool for developing nurses' competences and retaining excellent nurses in clinical practice.

Comparison of Three Different Culture Systems for Establishment and Long-Term Culture of Embryonic Stem-like Cells from In Vitro-Produced Bovine Embryos

  • Kim, Daehwan;Park, Sangkyu;Roh, Sangho
    • Journal of Embryo Transfer
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    • v.27 no.3
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    • pp.189-192
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    • 2012
  • Although embryonic stem cells (ESCs) or ES-like cells are reported from many mammalian species other than the mouse, the culture system for murine ESCs may not be suitable to the other species. Previously many other research groups have modified either human or mouse ESC culture systems for bovine ESC culture. In this study, we compared three different culture mediums consisting of DMEM, ${\alpha}$-MEM or KnockOut$^{TM}$-DMEM (KO), which are modified from human or mouse ESC culture system, for the generation of bovine ESCs. In this study, some pre-requisite events which are important for establishment and long-term propagation of ESCs such as inner cell mass (ICM) attachment on feeder cells, primary colony formation and sustainability after passaging. Once the ICM clumps attached on feeder cells, this was designated as passage 0. In regards to the rate of ICM attachment, ${\alpha}$-MEM was superior to the other systems. For primary colony formation, there was no difference between DMEM and ${\alpha}$-MEM whereas KO showed lower formation rate than the other groups. For passaging, the colonies were split into 2~4 pieces and passed every 5~6 days. From passage 1 to passage 3, DMEM system seemed to be appropriate for maintaining putative bovine ESCs. On the other hand, ${\alpha}$-MEM tended to be more suitable after passage 6. Although ${\alpha}$-MEM support to maintain a ES-like cell progenies to passage 15, all three culture systems which are modified from human or mouse ESC culture media failed to retain the propagation and long-term culture of putative bovine ESCs. Our findings imply that more optimized alternative culture system is required for establishing bovine ESC lines.

Estimation of Geostrophic Current Calculated from Sea Surface Topography in East Sea (동해의 해면지형 계산에 의한 지형류의 흐름 추정)

  • Yun Hong-Sic;Lee Dong-Ha
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.24 no.2
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    • pp.159-165
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    • 2006
  • This paper deals with the estimation of geostrophic current using the sea surface topography calculated from the geoidal height from EGM96 geopotential model and the mean sea surface height from CLS_SHOM mean sea surface model. The CLS_SHOM model was developed using the altimetry data set. The estimation of geostrophic current is available in the characteristic research of ocean in many country, while for East Sea a few studies were done. The goal of this study is basically to provide the characteristics of geostrophic current in East Sea. The results show that the mean sea surface topography (SST) in East Sea is about 0.37 m and the mean geostrophic velocity is -0.028 m/sec. The Pacific water enters into the East Sea through the Korea Strait and after passing the strait, this inflow splits into two branches: one flows northward along the Korean coast and another outflows into Pacific ocean through Tsugaru and Soya strait passing the east-northeastward along the Japanese outer shelf, and outflows into Okhotsk ocean.