• 제목/요약/키워드: long

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장섬유강화 고분자 복합재료에서 인장강도에 미치는 섬유배향의 영향 (Effect of Fiber Orientation on the Tensile Strength in Long-Fiber Reinforced Polymeric Composites)

  • 이동기;심재기;한길영;김혁;김진우;이정주
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.55-60
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    • 2003
  • Case that long-fiber reinforced polymeric composites of fiber orientation situation of a direction state is J=1 that is direction of tensile strength of another state appeared highest. And theoretical tensile strength value of long-fiber reinforced polymeric composites board of fiber orientation situation of a direction state appeared similarly with tensile strength value that long-fiber reinforced polymeric composites board of fiber orientation situation of a direction state. Also, than case that efficiency of fiber orientation situation of long-fiber reinforced polymeric composites is J=1 in it is J=0.1 of fiber orientation situation effect of long-fiber reinforced polymeric composites about 60% high appear.

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Bootstrap methods for long-memory processes: a review

  • Kim, Young Min;Kim, Yongku
    • Communications for Statistical Applications and Methods
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    • 제24권1호
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    • pp.1-13
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    • 2017
  • This manuscript summarized advances in bootstrap methods for long-range dependent time series data. The stationary linear long-memory process is briefly described, which is a target process for bootstrap methodologies on time-domain and frequency-domain in this review. We illustrate time-domain bootstrap under long-range dependence, moving or non-overlapping block bootstraps, and the autoregressive-sieve bootstrap. In particular, block bootstrap methodologies need an adjustment factor for the distribution estimation of the sample mean in contrast to applications to weak dependent time processes. However, the autoregressive-sieve bootstrap does not need any other modification for application to long-memory. The frequency domain bootstrap for Whittle estimation is provided using parametric spectral density estimates because there is no current nonparametric spectral density estimation method using a kernel function for the linear long-range dependent time process.

e-marketplace 이용기업의 신뢰가 몰입, 장기거래지향성, 협력에 미치는 영향 (Perceived Trust of e-Marketplace and Its Effect on Commitment, Long-Term Orientation and Cooperation)

  • 박준철
    • 한국정보시스템학회지:정보시스템연구
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    • 제16권2호
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    • pp.123-144
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    • 2007
  • As the interest in the business-to-business electronic commerce is increasing, many companies are participating in the business-to-business e-marketplaces. As a result, it is important to develop understanding of behaviors of firms that use these e-marketplaces. For this purpose, e-marketplace usage company trust is proposed to affect commitment, long-term orientation and cooperation. This study, which used data from participating in the business-to-business e-marketplace companies, showed acceptable data-fit of proposed model and supported all of research hypotheses. The empirical results indicated that trust take significant effect on commitment, long-term orientation and cooperation, and the commitment affect long-term orientation and cooperation, and the commitment in turn have strong influence on long-term orientation and cooperation. It was confirmed that commitment variable is effective mediator linking trust and long-term orientation and cooperation.

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부여 정림사지 도용 복원을 위한 농관 복식 연구 (A Study on Long-guan Costume to restore Clay Figures in Bu-yeo Jeong-lim Buddist Temple Foundation)

  • 박현정
    • 복식
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    • 제51권6호
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    • pp.25-38
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    • 2001
  • The purpose of this study is to investigate the character and costume of the long-guan clay figures that were excavated in Bu-yeo Jeong-lim Buddist temple foundation. For this, we first examine the Chinese official uniforms with long-guan, classify the types of long-guan, and then investigate the costume that is worn with long-guan. There are three types of long-guan in China, and that of the clay figures in Jeong-lim Buddist temple foundation is of type 1. Therefore, the characters of the clay figures are woman servants, and their costume is either blouse-and-trousers or blouse-and-skirt.

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한국산 녹색 말거머리 (Whitmania edentula)의 정자형성에 관한 미세구조 (Ultrastructural Study on the Spermatogenesis of the Korean Leech, Whitmania edentula)

  • 장남섭;한종민
    • Applied Microscopy
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    • 제27권3호
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    • pp.309-320
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    • 1997
  • The spermatogenesis of korean leech, Whitmania edentula was observed, using both light and electron microscopes. The spermatogonium and maturing spermatozoon are connected with long cytoplasmic process to the cytophore, which supplys nutrition to the germ cells and supports synchronous maturity. The truck of korean leech is divided into three regions; a long ladder-shaped acrosome and head, long middle piece and long tail. Long head region twists to the dextral helix, and nuclei are surrounded with microtubules (manchette).The nebenkern formed with long mitochondrion exists in the middle pieces, and a long tail of Whitmania edentula ($9\times2+1$ axoneme) differs from the $9\times2+2$ axoneme of Rhynchobdellae. The late cytophore is mostly formed with crystalloid matter and a number of lysosomes, and matured spermatozooms are engulfed into the late cytophore.

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Asset Allocation Strategies for Long-Term Investments

  • Kim, Chang-Soo;Shin, Taek-Soo
    • 재무관리연구
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    • 제25권4호
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    • pp.145-182
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    • 2008
  • As the life expectancy increases resulting in the aged society, the post-retirement life became one of the most important concerns of people. The long-term investment vehicles such as retirement savings and pension plans have been introduced to meet such demand of society. This paper examines the impact of asset allocation strategies on the long-term investment performance. Because of the unusually long investment horizon and the compounding effect, a suboptimal asset mix in a retirement plan can be a very costly and irreversible mistake. Instead of relying on anecdotal evidence to evaluate the merits of different allocation strategies, this paper performs various tests including stochastic dominance tests using both actual data and Monte Carlo simulated data that best fit the historical experience. The results indicate 1) the long-term investments perform better than the short-term investments, 2) the optimal asset allocation strategy for the long-term investments should be highly equity dominated.

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기업분할의 장기성과에 대한 실증연구 (The Corporate Spinoffs and Long-run Stock Returns)

  • 홍동현;이덕훈;황재호
    • 경영과정보연구
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    • 제25권
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    • pp.83-114
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    • 2008
  • We examine whether spinoffs improve long-run stock returns and analyze the factors of long run stock returns. The measures of long run stock returns are CAR(Cumulative Abnormal Returns) and BHAR(Buy and Hold Abnormal Returns). The expected factors of abnormal returns are methods of spinoffs, size, BV/MV, administrative costs, cashflow and Herfindahl index. We find that long-run returns of the case such as carve-out methods, small size, high BV/MV, low administrative costs, low cashflow and low Herfindahl index are larger than those of other cases. We show positive relationship between spinoffs and long-run stock returns(CAR and BHAR). The results supports spinoffs, as the methods of focusing on core business, are very usefulness of corporate restructuring.

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Mn-Mo-Ni 저합금강의 기계적 연화에 미치는 장시간 열처리 영향 (Effects of Long-term Heat treatment on Mechanical Softening of Mn-Mo-Ni Low-Alloy Steel)

  • 김민석;김정석
    • 열처리공학회지
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    • 제34권6호
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    • pp.294-301
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    • 2021
  • In the present study, we investigate the effects of long-term heat treatment at elevated temperatures on the mechanical softening of the Mn-Mo-Ni low-alloy steel. The influence of long-term heat treatment on microstructure and mechanical strength was evaluated. To simulate the long-term material degradation, heat treatment test was interrupted at several stages up to 10,000 hours in an electric furnace. The Mn-Mo-Ni low-alloy steel shows a typical bainitic phase, which consists of a well-developed lath substructure with fine precipitates along the lath boundaries. However, these fine precipitates were redissolved into the matrix with long-term heat treatment, and then the lath substructures were recovered. Consequently, ultimate tensile strength and yield strength decreased during long-term heat treatment showing a mechanical softening phenomenon.

장기요양서비스 수요의 결정요인 (Determinants of Demand for Long-Term Care)

  • 정완교
    • KDI Journal of Economic Policy
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    • 제31권1호
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    • pp.139-167
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    • 2009
  • 본 논문은 65세 이상 고령인구의 수와 노인들의 건강상태 등만을 중심으로 한 기존의 연구에 더하여, 노인장기요양보험제도 제2차 시범사업의 자료를 이용한 계량분석을 통해 장기요양서비스 수요의 결정요인을 분석하였다. 분석 결과에 따르면, 우선 노인장기요양보험제도상 장기요양서비스 이용에 대한 보험 적용 대상자를 정하는 등급판정에 일상생활활동에서의 장애가 노인들이 많이 앓고 있는 고혈압, 관절염, 치매 등의 질환을 통제하고서도 통계적으로 유의한 영향을 미쳤다. 또한 노인들의 건강상태, 여성, 기초생활수급자 여부, 노인가구 형태, 노인가구의 월평균 소득 등이 장기요양서비스이용 및 이용 양태에 통계적으로 유의한 영향을 미치는 것으로 나타났다. 특히, 노인가구의 월평균 소득을 통제하고서도 장기요양서비스를 무료로 이용할 수 있는 기초생활수급 대상 노인들의 재가서비스 이용확률이 높게 나타나는데, 이는 소득과 더불어 장기요양서비스의 가격도 장기요양서비스 이용을 결정하는 중요한 요인임을 의미한다.

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기관 협착에서 Long T-tube의 삽입 방법 (A technique for insertion of a long T-tube in tracheal stenosis)

  • 백만종
    • Journal of Chest Surgery
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    • 제26권8호
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    • pp.664-666
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    • 1993
  • A technique for insertion of a long silicone T-tube in patient with critical stenosis and high-risk resection and primary anastomosis of long segment of the distal trachea is presented. It was not easy to insert a long T-tube by existing methods because of flexibility of a T-tube and tightness of stenosis. So we used a silastic endotracheal tube and guiding wire as stylet of a T-tube. During insertion, ventilation was normally maintained through the lumen of endotracheal tube. This provided rapid relief from airway obstruction and asphyxation and is a easy, safe and effective method to restore patency of the major airways.

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