• 제목/요약/키워드: host factors

검색결과 534건 처리시간 0.022초

풍력발전시스템이 연계된 계통의 과도안정성에 영향을 미치는 요소 (Factors Influencing Transient Stability in Network Connected to Wind Power Generation System)

  • 김세호;오성보;고성민;안재현;이수묵;장시호;이효상
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.535-536
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    • 2006
  • This paper reports investigation into the factors that influence the transient behavior of the wind power generation system following network fault conditions. It is shown that the critical clearing time(CCT) can be affected by various factors contributed by the host network. Such factors include capacity of wind power, power factor, the length of the interfacing line, etc. This investigation is conducted en a simulated grid-connected wind farm using Digsilent Power Factory.

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Credit Enhancement and its Risk Factors for IPP Projects in Asia: An Analysis by Network

  • Chowdhury, Abu Naser;Chen, Po-Han
    • 국제학술발표논문집
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    • The 6th International Conference on Construction Engineering and Project Management
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    • pp.122-126
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    • 2015
  • Credit enhancement is absolutely essential for financing Independent Power Producer (IPP) projects in Asia particularly for countries whose sovereign credit rating is on non-investment grade and foreign investment is difficult to achieve. Due to nexus of agreements among varies parties in IPP project, it is hard to clearly visualize the roles of these agreements. Examples are: What credit enhancement factors are most influential to minimize the associated risks of IPP projects? Why are they powerful? What are their roles? Who are less powerful and what are the obstacles that causes them less powerful? A research is conducted to identify the credit enhancement factors for IPP projects in Asia. IPP professionals validated 27 out of 28 identified credit enhancement factors, and five factor groupings were made through factor analysis. Afterwards, network theory is applied to find the unanswered questions, which by graphical and mathematical representations show that the host government's credit enhancement, MDBs, ECAs and other parties' credit enhancement are prominent and of great importance to handle the associated risks of IPP projects in Asia

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갈색날개매미충(Pochazia shantungensis) (Hemiptera: Ricaniidae)의 기주식물, 발생지역 및 잠재서식지 예측 (Predicting the Potential Habitat, Host Plants, and Geographical Distribution of Pochazia shantungensis (Hemiptera: Ricaniidae) in Korea)

  • 김동언;이희조;김미정;이도훈
    • 한국응용곤충학회지
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    • 제54권3호
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    • pp.179-189
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    • 2015
  • 본 연구에서는 2014년 전국을 대상으로 갈색날개매미충의 국내 분포, 기주식물, 잠재서식지를 조사하였다. 갈색날개매미충은 43개 시군에서 관찰되었고, 경북에서 처음 확인되었다. 기주식물은 산지 및 농작물에서 53과 113종으로 확인되었고, 선행연구를 포함하여 62과 138종으로 조사되었다. 주요 기주식물은 사과나무, 두릅나무, 때죽나무, 갯버들, 닥나무, 자귀나무, 가죽나무, 밤나무, 아까시나무, 산수유 등이었다. 종분포 예측은 Maxent 모형을 사용하였고, 12개의 모형변수(8개 기후변수, 1개 토지피복변수, 1개 임상변수, 1개 생태자연도 변수, 1개 거리변수)를 활용하였다. 모형의 정확도는 0.884로 매우 우수하였다. 연구결과에 의하면 여름철 강수량, 여름철 평균기온, 임상현황, 토지이용현황이 갈색날개매미충의 잠재서식지에 영향을 미치는 중요한 요인으로 밝혀졌다.

제도적 거리와 해외직접투자의 관계에 관한 연구: 중국을 중심으로 (A Study on the Relationship Between Institutional Distance and Outward Foreign Direct Investment: the Case of China)

  • 림아신;유천;황윤섭
    • 무역학회지
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    • 제48권4호
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    • pp.23-45
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    • 2023
  • 본 연구는 제도적 거리와 해외직접투자의 관계를 규명하기 위한 것으로 중국의 해외투자를 대상으로 수행한다. 중국과 투자 유치국 간의 제도적 거리는 세계은행에서 발표한 제도적 품질을 이용한다. 2008년부터 2019년까지 중국이 투자한 50개국의 패널 데이터를 수집하여 패널 GLS 방법론을 통해 해외직접투자에 영향을 미치는 요인을 제도적 관점에서 다음의 3가지를 검증한다. 첫째, 중국의 해외직접투자 전체 국가들을 대상으로 제도적 거리의 절대값이 중국의 OFDI에 미치는 영향이다. 두 번째는 중국과의 제도적 거리가 양(+)인 국가와 음(-)인 국가의 두 그룹으로 나눈 후 각 그룹에서의 제도적 거리와 OFDI의 관계이다. 마지막으로 제도적 거리와 중국의 OFDI 사이의 비선형 관계이다. 이를 위해 제도적 거리의 제곱항을 분석 모형에 추가한다. 분석 결과는 다음과 같다. 제도적 거리는 중국의 OFDI와 정(+)의 관계가 확인된다. 중국보다 상대적으로 제도 품질이 높은 진출국 그룹에서는 제도적 거리와 OFDI는 역 U자형 관계가 나타나지만, 낮은 진출국 그룹에서는 정(+)의 관계가 나타난다. 또한, 중국의 OFDI는 제도적 요인과 경제적 요인의 복합적인 영향을 받는 것으로 확인된다. 본 연구의 결과는 FDI 유치국뿐만 아니라 다국적 기업의 FDI 진출국 선택에 있어서 시사점을 제공할 것이다.

Risk factors for short term thyroid dysfunction after hematopoietic stem cell transplantation in children

  • Jung, You Jin;Jeon, Yeon Jin;Cho, Won Kyoung;Lee, Jae Wook;Chung, Nack-Gyun;Jung, Min Ho;Cho, Bin;Suh, Byung-Kyu
    • Clinical and Experimental Pediatrics
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    • 제56권7호
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    • pp.298-303
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    • 2013
  • Purpose: The purpose of this study was to evaluate short-term thyroid dysfunction and related risk factors in pediatric patients who underwent hematopoietic stem cell transplantation (HSCT) during childhood. Methods: We studied 166 patients (100 boys and 66 girls) who underwent HSCT at the Catholic HSCT Center from January 2004 through December 2009. The mean age at HSCT was $10.0{\pm}4.8$ years. Thyroid function of the patients was tested before and during 3 months of HSCT. Results: Out of 166 patients, 165 (99.4%) underwent allotransplantation. Acute graft-versus-host disease (GVHD, grades II to IV) developed in 76 patients. Conditioning regimens before HSCT include total body irradiation (n=57), busulfan (n=80), and reduced intensity (n=29). Forty-five (27.1%) had thyroid dysfunction during 3 months after HSCT (29 euthyroid sick syndrome [ESS], 6 subclinical hyperthyroidism, 4 subclinical hypothyroidism, 3 hypothyroxinemia, 2 overt hyperthyroidism, and 1 high $T_4$ syndrome). In a univariate logistic regression analysis, age at HSCT (P=0.002) and acute GVHD (P=0.009) had statistically significant relationships with thyroid dysfunction during 3 months after HSCT. Also, in a univariate logistic regression analysis, ESS (P=0.014) showed a strong statistically significant association with mortality. Conclusion: In our study 27.1% patients experienced thyroid dysfunction during 3 months after HSCT. Increase in age and acute GVHD may be risk factors for thyroid dysfunction during 3 months after HSCT. There was a significant association between ESS and mortality.

Sliding-DFT를 이용한 다채널 위상 측정 FPGA 시스템 (Sliding-DFT based multi-channel phase measurement FPGA system)

  • 어진우;장태규
    • 전기전자학회논문지
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    • 제8권1호
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    • pp.128-135
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    • 2004
  • 본 논문에서는 sliding-DFT에 순환 구현에 기반한 위상 측정 앨고리즘을 제안하였다. 제안한 앨고리즘은 주파수 변이, 누적 잡음, 계수 근사 영향 등의 오차영향에 강인한 특성을 가지도록 설계되었다. DFT 계수의 유한 비트 근사 구현에 의한 위상 오차는 크기 오차에 비해 매우 작게 나타난다. 위상 오차의 혁신적인 감소는 근사 계수가 복소평면 상에서 4사분면상에 대칭적으로 존재함을 이용하여 얻을 수 있다. 제안한 앨고리즘을 시분할 공유 구조에 기반한 4-채널 전력선 위상 측정 시스템을 설계하고 구현하였다. 구현한 시스템의 동작은 실시간으로 host processor 시스템과 다채널 함수 발생기를 통한 test 환경에서 실험적으로 확인하였다. 제안한 앨고리즘의 위상 측정에 있어 정확한 특성과 유한비트 근사 영향에 강인한 특성은 특히, 빠른 처리 속도와 구현의 감소함이 주요 설계 고려사항인 ASIC 이나 microprocessor에 기반의 임베디드 시스템 적용에 중대한 효과를 제공할 수 있을 것이다.

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EFL Context and Learners' Affective factors in Korean Secondary Education

  • 박혜순
    • 영어어문교육
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    • 제12권1호
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    • pp.55-75
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    • 2006
  • This paper attempts to discuss the complex nature of social contexts regarding English language education in Korean middle school and to demonstrate the affective factors that should be considered to find appropriate approaches within the context. To do this, a questionnaire survey was conducted among 85 middle school students regarding learners' motivation, and attitudes toward EFL learning. Additionally, teachers in secondary school were asked about the general circumstances of English language education. Findings indicate that in spite of the participants' high instrumental motivation, they rather show a negative attitude toward English learning. This paper intends to raise practitioners' attention to the fact that the effect of learners' affective variables on EFL learning seems distinctive depending on the host country's EFL contexts.

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Recent Advances in the Innate Immunity of Invertebrate Animals

  • Iwanaga, Sadaaki;Lee, Bok-Luel
    • BMB Reports
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    • 제38권2호
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    • pp.128-150
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    • 2005
  • Invertebrate animals, which lack adaptive immune systems, have developed other systems of biological host defense, so called innate immunity, that respond to common antigens on the cell surfaces of potential pathogens. During the past two decades, the molecular structures and functions of various defense components that participated in innate immune systems have been established in Arthropoda, such as, insects, the horseshoe crab, freshwater crayfish, and the protochordata ascidian. These defense molecules include phenoloxidases, clotting factors, complement factors, lectins, protease inhibitors, antimicrobial peptides, Toll receptors, and other humoral factors found mainly in hemolymph plasma and hemocytes. These components, which together compose the innate immune system, defend invertebrate from invading bacterial, fungal, and viral pathogens. This review describes the present status of our knowledge concerning such defensive molecules in invertebrates.

TV 홈쇼퍼의 강박구매에 관한 연구: 쾌락적 쇼핑성향과 마케팅 자극 요인을 중심으로 (TV Home Shoppers' Compulsive Buying: Shopping Orientation & Marketing Promotion Variables)

  • 이승희;허세정
    • 패션비즈니스
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    • 제13권5호
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    • pp.102-109
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    • 2009
  • The purpose of this study was to investigate TV home shoppers' compulsive buying, focused on shopping orientation and marketing promotion variables. Four hundred one female home shoppers who have purchased fashion products through TV home shopping. For data analysis, descriptive statistics, factor analysis, t-test, and Cronbach's Alpha were used in this study. The results were as follows: First, approximately 17% of respondents were revealed as compulsive buyers. Second, for shopping orientation instrument, three factors of shopping orientation were found and labeled as 'indifferent', 'hedonic', and 'economic' factors. Third, compared to non-compulsive buyers, compulsive buyers had higher hedonic scores. Finally, compulsive buyers considered marketing promotion variables such as show host, scarcity sales, gift events as important factors for their purchasing than non-compulsive buyers. Based on these results, it would provide TV home shopping marketers efficient and social responsible marketing strategies.

Determinants of Bilateral Foreign Direct Investment Intra-ASEAN : Panel Gravity Model

  • Zebua, Hasrat Ifolala;Nasrudin, Nasrudin
    • Asian Journal of Business Environment
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    • 제6권1호
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    • pp.19-24
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    • 2016
  • Purpose - This paper aims to find and analyze factors that determine the flows of bilateral foreign direct investment in intra-ASEAN. It specifically focuses on the dimension of macro-economic, natural resources, human resources, and the quality of governance. Research design, data, and methodology - Data were collected from 64 bilateral relations between ASEAN nations from 2002 to 2013. Panel gravity model was utilized to find factors that determine the flows of bilateral foreign direct investment. Results - Significant factors were identified that determine the flows of bilateral foreign direct investment: GDP home country, GDP host country, real interest rate, distance, and total natural resources rent. Unexpectedly, natural resources have a negative effect. Conclusions - In a situation of increasing the flow of FDI among the countries of ASEAN, the government should control the interest rates and maintain good relations with nearby countries. The negative effect of total natural resource rents implies that ASEAN countries should not depend on their natural resources to attract foreign investments.