• Title/Summary/Keyword: 하락 원인

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전기유동유체(ERF)를 이용한 지능구조물 시스템의 구성 및 응용

  • 최승복;박용군
    • Journal of KSNVE
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    • v.5 no.3
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    • pp.275-283
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    • 1995
  • 본 글에서는 지능구조물의 개념설명과 더불어 ERF의 특성, ERF를 함유란 함유 한 지능구조물 시스템의 구성, 동적 모델링과 진동제어 그리고 그 응용성에 관한 연구 현황과 방향에 대해 살펴보았다. 설명한 바와 같이 지능구조물은 새로운 차원의 신생 하는 첨단분야로서, 소음 및 진동에 관련된 무한한 잠재력과 다양한 응용성으로 미루 어 볼때 아주 매력적인 연구 분야이다. 그러나, 여러 응용 시스템의 상품화 단계로의 도약에 있어서 각 시스템 구성 요소 분야별 해결해야할 연구 사항들이 있다. 먼저, 액추에이팅을 수행하는 ERF 자체의 내구성 문제로서 고온에서 ERF의 효과 하락과 장시간 사용시 ERF에 의한 마멸, 고체 입자의 침전에 의한 초기 상태 불안정 등이 있다. 아울러 기존의 장치의 성능을 능가하기 위해 보다 큰 효과를 나타내는 새로운 차원의 ERF개발이 요구된다. 그리고 센서기술 분야에서는 호스트 재료에 보다 쉽게 결합이 되고 여러가지 형태의 요구조건을 만족시킬 수 있으며 외부 환경조건에 강건 하고 다양한 센서 개발이 요구된다. 또한, 보다 일번적인 동적 모델링을 통해 적용 시스템에 적합하고 강건한 제어기에 대한 연구가 진행되어야 한다. 마지막으로 능동 제어기를 실제로 구현하기 위한 호스트 재료 각 요소마다 센서의 설치, 페회로 피드백 시스템 장착, 상호간의 인터페이스 등의 기술 발전이 요구되며, 아울러 보다 효율적 인 시스템의 성능 특성을 실현할 수 있는 호스트 재료와 기계 메카니즘이 필요로 된다. 이상의 설명에서 알 수 있듯이 지능구조물에 대한 연구는 어느 한 분야에서만 아니라 기계, 전기전자, 토목, 물리, 재료과학 등 통합형식에 의한 접근 방향으로 추진되어야 할 것이다.서 세탁기의 진동 소음을 저감시키기 위해 진동 소음원에 대해 논술하고, 진동해석을 위해 컴퓨터 시뮬레이션 결과를 이용한 저진동 기술 개발에 대하여 기술하고자 한다.rotary piston)식 압축기는 약 20여년 전 부터 냉방용 압축기에서부터 널리 쓰이게 되었다. 약 10여년전부터 상용화 된 스크롤(scroll) 형 압축기도 현재 상대적으로 용량이 큰 가정용 냉방기를 중심으로 많이 쓰이고 있다. 스크류형 압축기는 보통 중대형 상업용에 주로 쓰인다. 해결하려 하였고, 수치해석은 피스톤의 운동을 배제한 단순화한 흡배기계의 정상상태 유동해석이 주를 이루어왔다. Taghaui and Dupont 등[5]은 KIVA코드를 사용하여 흡기포트와 연소실 그리고 밸브의 움직임을 동시에 고려한 수치해석을 도입하였다. 하지만 이들이 밸브의 운동을 고려하기 위해 사용한 이동격자는 격자점은 시간에 따라 변화하지만 그 격자의 수가 일정하게 유지되어 있어서 밸브의 완전개폐를 해석할 수가 없다. 강희정[6]은 단일 실린더와 단일 배기밸브를 갖는 문제로 단순화하여 피스톤과 밸브의 움직임을 고려하므로써 배기행정 후 소음이 어떻게 전파해 나가는가를 연구하였다. 본 연구에서도 최소밸브간격과 최대밸브간격 사이에서만 계산이 가능하나 흡기의 경우는 밸브가 닫힐 때 생기는 압력파가 중요하므로 실린더와 밸브사이에 벽면조건을 주어 밸브의 개폐를 모사하였다.술을 보유하고자 한다. 이용한 해마의 부피측정은 해마경화증 환자의 진단에 있어 육안적인 MR 진단이 어려운 제한된 경우에만 실제적 도움을 줄 수 있는 보조적인 방법으로 생각된다.ofile whereas relaxivity at high field is not affected by τS.

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국내 사외보 편집디자인에 관한 연구-5개 그룹 사외보 편집디자인을 중심으로-

  • 남혜인
    • Archives of design research
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    • v.11 no.3
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    • pp.127-134
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    • 1998
  • Enterprise which is rapidly growing in Korea is hesitating because of economic depression lately. Large enterprise have been successfully growing with Korea economic growth for fifty years. But many of them have already gone bankrupt and face the crisis of management, many people look away from them. Large enterprise come to face the time which they strongly need the improvement of their image against the devalation of their one. It is more important to use external periodicals than excess PR advertisement for the improvement of the image. External periodicals is aimed at readers who is outside of company and company PR advertisement, the purpose of issuing external periodicals is to improve the image of enterprise by arranging organization, draw attention from people (PR) and produce profit by acceleration marketing. People is much interested in external periodicals(free) under the situation of IMF because they can easily get information from that. So the role of external periodicals become more important for enterprise PR. This paper shows the importance of the edit design in external periodicals. We analysed the edit design (five group) per composition factor, suggest the improvement plan. ·The distinction of cover. ·Clear, beautiful typographic arrangement. ·The specialty of Photo and illustration. · Characteristic & standard layout. Now external periodicals is getting important because it shows the idea and character of company to people (PR). So it need characteristic plan and creative layout with the impotance by the understanding of the executive in company and also more does creation & originality by edit designer day by day. External periodicals should be not only the improvement of the image but also leading information paper which sensitively cope which an age by news and editing which can match people's need.

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Preparation and Quality Characteristics of Mul-kimchi Added with Chlorella (클로렐라 분말을 첨가한 물김치의 제조와 품질특성)

  • Kim, Dong Chung;Won, Sun Im;In, Man-Jin
    • Journal of Applied Biological Chemistry
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    • v.57 no.1
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    • pp.23-28
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    • 2014
  • Mul-kimchi was prepared with addition of 0.025, 0.05, and 0.1% (w/v) chlorella powder and fermented at $10^{\circ}C$ for 6 days. Quality characteristics of the Mul-kimchi were evaluated in terms of acid production (pH and titratable acidity) and lactic acid bacterial counts during fermentation. The addition of chlorella powder stimulated the growth of lactic acid bacteria and significantly enhanced the acid production. After 3 days fermentation, titratable acidity of chlorella Mul-kimchi was 0.12-0.14% and was higher than that (0.11%) of Mul-kimchi made without chlorella. The acid production and the number of viable lactic acid bacterial cell increased with increasing the concentration of added chlorella powder. The sensory score of Mul-kimchi added with 0.05% chlorella powder showed the highest values in taste and overall acceptability among the tested Mul-kimchi preparations. When chlorella Mul-kimchi preparations incubated for 3 days were kept at $4^{\circ}C$ for 19 days, their quality characteristics were well maintained through storage period. According to sensory score and storage ability, the optimum concentration of chlorella powder was around 0.05%.

An Ex-ante Analysis of Lifting the Japanese Pear's Import Ban on SPS (일본산 배 SPS 수입금지 조치 해제의 사전분석)

  • Han, Suk-Ho;Seo, Hong-Seok;Youm, Jung-Won
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.1
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    • pp.599-608
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    • 2017
  • This paper proposed a methodology to analyze the economic and quantitative effects of lifting the import ban on Japanese pears by applying a price gap approach in the absence of any preference for either type of pear. Assuming that Korea will allow Japanese pear imports in 2018, the simulation results show that an annual average of 50,000 tons will flow into the domestic market from Japan. These imports will cause a decrease in the price and production of domestic pears, which would have a direct effect on the domestic pear industry, leading to an annual average reduction of 93 billion won. The cultivation area and production quantity are projected to be decreased by 0.7% and 1.4%, respectively, compared to the baseline. Also, the annual average reduction in the overall agriculture sector is predicted to be about 209 billion won, which is a 0.4% reduction compared to the baseline. This research is expected to improve the methodologies available for proactive analysis, with the existing analysis focused on customs tariffs when Korea considers joining mega-FTAs.

A Study on the Enhancing of the Global Competitiveness of the Services of Tax, Law, and Accounting - Focusing on Multi-Disciplinary Practices(MDP) - (조세·법률·회계 서비스의 국제경쟁력 제고 방안 - 이종자격사간 동업(MDP)을 중심으로 -)

  • Son, Yun;Lee, Hak-loh
    • International Commerce and Information Review
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    • v.19 no.4
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    • pp.53-74
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    • 2017
  • There have been growing concerns that Korea's products keep losing their international competitiveness. It is necessary to restore strong muscles of manufacturing sectors. Together, efforts must be made to strengthen the competitiveness of service sector. While wide consensus has been reached on the necessity that Korea's service sector needs overhaul for stronger global competitiveness, it is rather difficult to witness any remarkable improvements. Insufficient performances might result from the protection of the captive markets by the interested parties. The research starts from the proposition that the introduction of MDP will bring down the barriers between the segmented services and promote competition. We provide theoretical analyses and report better performances of major countries which introduced MDP in their soils. Considering the reality, we propose that in the foreseeable future, a MDP in the areas of tax, law and accounting be introduced in Korea because these areas seem to create least conflicts of disciplinary duties due to public purposes. Broader MDPs in other areas may take some more time. There exist, however, some limitations. As MDP has not been officially introduced in Korea, it is almost impossible to directly compare the performances between the pre- and post-MDP in Korea. Data scarcity of business performances of companies also limits the study.

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Cultural Politics of Gendered Schadenfreude Surrounding an Idol Focusing on the debate over IU (아이돌을 둘러싼 젠더화된 샤덴프로이데(Schadenfreude)의 문화정치학 <아이유 사태>를 중심으로)

  • Kim, Hyun Gyung
    • Korean journal of communication and information
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    • v.80
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    • pp.115-142
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    • 2016
  • This study aims to reveal the content of and logic behind a recent negative public sentiment toward female idols with the example of a debate over songstress IU's fourth album that was released late last year. While previous studies on fandom have focused on the identification process towards entertainers and making community, a recent phenomenon of "anti-fandom" or "malicious comments" implies that more research is needed on negative emotions such as hostility or schadenfreude (feelings of pleasure from others' misfortunes). Schadenfreude is a social sentiment that originated in modern liberalism, which features contradictions between public equality and private ownership, and that has been intensified in neoliberalism, which features a maximization of this contradiction centering on a meritocracy. Celebrities in Korea often become the targets of schadenfreude, which is associated with the suspicion that they gain popularity not from their abilities but from "just being popular." It should also be noted that this kind of schadenfreude operates differently between male and female entertainers. Specifically, the acquisition of money and fame by modern women whose presence used to be located in the private possessions of males is considered to be due to their unjustified use of sexuality. This is also the background of the recent online misogyny culture in Korea. In this context, IU, who had been successful at building a differentiated image of "sister-like idol artist," became a valid target. Although accusing IU of utilizing pedophilia reflects a stalemate that a current politics of sexual violence faces, it rather damages the name of an individual than attracts public attention to the structural causes of childsexualabuse. This is why I see the way that pedophilia was used in the debate over IU as a schadenfreude. Consequently, the term pedophilia here contributes to an expansion of the entertainment economy that is sustained by rises and falls of the celebrities' stock prices.

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An Integrated Model on the Determinants of Successful Post-M&A Information Systems Integration: A Comparative Case Study of Two Financial Firms in Korea (인수.합병 이후 성공적인 정보시스템 통합 결정요인에 대한 통합적 모델 연구: 국내 금융기관 비교사례분석 중심으로)

  • Lee, Chang-Jin;Lee, Jung-Hoon
    • Information Systems Review
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    • v.11 no.2
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    • pp.45-66
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    • 2009
  • A number of companies are considering for merger and acquisition (M&A) as one of business strategies for their growth and survival. However, many of them do not create the synergy they had sought, and failed M&A, often result in negative outcomes in terms of productivity, market share, profitability and turnover of qualified employees. There have been numerous research studies conducted to analyze the factors that determine the success and failure of M&A, and it has been found that with the increasing dependence of many companies on information systems, post-M&A IS (information systems) integration success has a critical effect on the success of M&A. However, there have been very few studies on post-M&A IS integration success, and most have been restricted to integration of IS organizations or physical information systems. In order to conduct a comprehensive research on the factors that affect the success of post-M&A IS integration, this study surveyed preceding researches on not only information systems but also strategic management, economics, finance, HRM (human resource management) and organization management. Based on the findings, a comprehensive and integrated model of the influential factors on post-M&A IS integration has been proposed. The proposed model categorizes the factors into perspectives of M&A, strategy, organization, HRM and IS, and provides an empirical evaluation of each factor on the success of IS integration based on comparative case studies.

‘고유가뚫어라’모토시리즈 - 작년40% 급등한유가올해도‘고공비행’

  • Korea Electric Association
    • JOURNAL OF ELECTRICAL WORLD
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    • s.349
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    • pp.90-94
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    • 2006
  • “해마다늘어만가는지구촌곳곳의기상이변, 특히세계유전지대의혹독한풍수해가지난해와마찬가지로일시에밀어닥친다면올해도국제유가의고공행진은하늘을찌를것이다.” 고유가가대세로점쳐지고있는가운데 2 0 0 6년새해를맞아유가의고공행진에대한극단적인우려감이높다. 지난해지구촌이 겪은미국발 허리케인의공포가채 가시지 않은 탓이다. 고유가의정착으로 인해고통을감내한 세계각국은올해초 국제유가의향방을대부분부정적으로내다보고있다. 고유가의원인으로는수요급증에따른수급불균형을우선꼽으면서도고공행진의유가를촉발할여러가지변수도다각도로진단하고있다. 지난해40% 가까이급등한국제유가는올한해에도고공비행을계속할것으로보고있는가운데일부언론은유가 6 0달러시대는이제기정사실화됐다고보도하기도했다. 만약부정적인상황이온다면“WTI 가격은최고 8 0달러, 두바이유가격은최고 6 7달러수준까지상승한다”는전망이나오는가하면“미국과이란의정치적충돌로페르시아만폐쇄사태라도터진다면유가가배럴당 1 0 0달러까지도치솟을수있다”는 경고도 나오고 있다. 우려는 하되 긍정적인 시각도 있다. 고유가가 올해 인플레에 미칠 영향에 대해 경제협력개발기구( O E C D ) 의코엔빈센트수석애널리스트가바로이경우다. 그는최근의고유가는지난 7 0년대와 8 0년대초의석유파동때와는성격이다르다고전제하면서다음과같이진단했다. “당시는공급쪽의충격이컸으나이제는수요급증으로발생하는것”이라고지적하며“선진권경제의석유의존도가크게떨어진점도고유가의파고가큰우려가되지않는다”고밝히고있다. 국내 전문가들도중동정세가 안정되고 미국 경기가 크게 둔화돼 석유수요가감소할경우에도 O P E C의 적극적 감산이예상돼유가가 4 0달러대밑으로내려가기는어려울것으로내다보고있다. 케임브리지에너지연구소( C E R A ) 의경우브렌트유기준으로 지난 연말 배럴당 5 5 . 4달러에서 올해는 5 3 . 5달러로되레떨어질것으로내다봤다. 2006년미국과중국의석유수요가대폭둔화될경우배럴당 4 1 . 3달러까지하락할수도있다는전망을내놨다. 그러나주요산유국의공급차질로인한비관 적인상황이도래할경우엔배럴당7 6달러까지도급등할것이라는경고도덧붙였다. 하여튼 2 0 0 6년유가의향방은고공추세에다주변변수가어떻게잘마무리되느냐, 나아가돌발풍수해에따라선‘껑충’거릴수밖에없다는진단이우세하다. 새해를맞아최근의국제유가동향과나아가유가의향방및변수를진단해봤다.

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A Reversal in Retirement Ages and the Future of Social Policy in the United States (미국인의 조기퇴직 역전현상과 고령자 사회정책의 미래)

  • 전광희
    • Korea journal of population studies
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    • v.26 no.1
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    • pp.115-141
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    • 2003
  • The aim of this paper is to describe a long-term trend toward earlier retirement and its reversal since 1985 in the United States, together with changes in socioeconomic conditions and social-policy programs which have contributed to this new development. The American people's recent propensity to retire at relatively younger ages was mainly a result of secular increase in individual wealth that had made it possible for them to enjoy higher standard of living without their participation in labor market activities at older ages. In addition to the introduction of compulsory retirement system, both social security retirement pension program and corporate pension system have also contributed significantly to the declining retirement age and its reversal around the mid-1980s. This paper pays full attention to the set of social policy programs which are currently being used to sustain the recent reversal in ages at retirement. The basic question to be raised here, however, is about whether or not the U. S. government will ave to continue to implement the social policies and programs used to discourage the elderly from retiring at relatively younger ages in the future. In this paper, it is argued that labor productivity growth and improvement in work attitude prior to retirement will help the elderly find little difficulties in having higher standard of living, despite their further lengthening of life expectancy at birth and post-retirement survival chances, the latter being often called the "third life". Most American people hope that the social-policy programs that have promoted early retirement will remain unchanged in the first part of the 21st century while they will put significant financial burden on their future descendants who have to work in the paid labor market. Taking this observation in consideration, this paper concludes that the U. S. government has to focus more on developing the programs that improve work propensity and labor productivity among the currently working-age population rather than continuing to implement the programs that sustain the recent reversal in retirement ages.ment ages.

Correlation of Microstructure with Mechanical Properties by Welding Conditions of Electric Resistance Welding(ERW) (전기저항용접(ERW)조건에 따른 미세조직과 기계적 특성의 연관성)

  • Lee, Kyung-Min;Lee, Dong-Eon;Kim, Sung-Woong;Yoon, Byung-Hyun;Kang, Hee-Jae;Kang, Nam-Hyun
    • Proceedings of the KWS Conference
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    • 2010.05a
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    • pp.27-27
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    • 2010
  • 청정에너지원의 수요가 증가함에 따라 에너지원의 공급로의 역할을 하는 강관의 수요가 증가하고 있다. 소재가공 기술의 발전과 함께 경량의 고장력 강재의 적용은 공급로의 역할을 하는 강관의 비용절감 및 자원의 효율적 이용 측면에서 지속적으로 연구 개발을 이어왔다. 이러한 추세에 따라 구조용 또는 라인파이프용 강관에서도 고장력 강재의 적용과 함께 고인성 그리고 용접성의 향상을 위한 다양한 라인파이프용 강재의 개발과 이의 적용이 그간 활발히 진행되어왔다. 용도상 반드시 필요한 특성인 고장력, 고인성, 용접성 등 외에도 다양한 강재의 사용에 따른 제조공정상 즉 용접공정에서 발생될 수 있는 용접부의 기계적 특성 변화에 대한 특성 연구 및 기술 연구가 계속 되어왔다. 주로 강관을 생산하는데 쓰이는 ERW (Electric Resistance Welding) 공정에서도 이러한 문제점을 해결하기 위해 많은 연구가 진행되고 있다. ERW는 높은 생산성과 낮은 제조비용의 장점을 가지고 있으나 용접 후 용접부의 기계적 특성 감소로 인한 단점이 있다. 때문에 기계적 특성향상을 위해 최적의 용접조건에 대해 연구해야 할 필요가 있다. 본 연구에서는 4가지 합금강관의 ERW 용접시 용접 입열량의 변화와 용접부의 후열처리를 통한 미세조직의 변화와 기계적 특성에 대해서 고찰하였다. 4강종 시편의 미세조직을 OM, SEM을 통한 분석 이후 인장시험 및 경도시험 등을 통해 기계적 특성을 평가하였다. 대부분의 시편에서 입열량의 증가에 따라 Ferrite 분율이 증가하였고 용접중앙부의 Ferrite 양이 용접경계부 보다 많았다. Ferrite 집중부의 분포가 극명하게 관찰되었던 DP780 (적정) 강종과 미세하게나마 Ferrite 집중부가 존재하였던 K55 (과소, 과대) 강종에서 나란히 경도 하락 현상이 관찰되었다. 이는 강종마다 고유의 Ceq, 합금 중 Mn 농도, 입열량 등에 의한 복합적인 이유 때문으로 판단된다. 탄소가 0.3~0.4 wt% 함유된 중탄소강인 S45C, K55의 경우 용접중앙부와 용접경계부의 페라이트 분율 차이가 큰 것을 알 수 있었다. 이는 용접시 열에 의한 탈탄현상으로 인해 나타나는 현상으로 판단된다.

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