• 제목/요약/키워드: restricting factor

검색결과 33건 처리시간 0.033초

풍력발전기 출력제한을 고려한 풍력한계용량 산정에 관한 연구 (A study on the maximum penetration limit of wind power considering output limit of WTGs)

  • 김형택;명호산;김세호
    • 한국태양에너지학회 논문집
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    • 제31권6호
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    • pp.23-31
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    • 2011
  • The wind energy is one of the most prospective resources in renewable energy. However, the WTGS shouldn't be installed indiscriminately because the power system can be negatively influenced by a variable and uncertain nature of the wind energy. It is the reason why it has to be limited to install the WTGS thoughtlessly mentioned above that support the importance of the maximum penetration limit of wind power. It may required that power system operators suggests a new way of power system operation as percentage of the WTGS increase in the existing power system. The wind power is fixed in a limited area, so using rate of the wind power will be increased by installing additional WTGS. In this paper, we have studied on economic evaluation of the wind capacity increased by restricting the output of the WTGS as the way to increase the wind capacity.

셀룰라 무선 망에서 실시간 패킷 전송을 위한 핸드오프 프로토콜 개선 (Inprovement of Handoff Protocol for Real-Time Packet Transmission in Cellular Wireless Networks)

  • 한승진;이정현
    • 한국정보처리학회논문지
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    • 제7권11S호
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    • pp.3675-3683
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    • 2000
  • 한정된 지역에서 벗어나 여러 지역으로 이동을 하며 데이터를 송수신하고자 할 때 필요한 핵심 기술 요소가 핸드오프이다. 기존의 연구들은 MH가 이동하려는 셀로 패킷을 전달하는 방식으로 핸드오프 시 발생되는 패킷의 손실을 최소화하려 했다. 그러나 핸드오프 도중에 발생되는 패킷의 손실 양이 비록 적다 하더라도 누적이 된다면 TCP 성능을 감소시킬 수 있고, 이는 패킷의 손실에 민감한 부분이면 중요한 문제가 된다. 본 논문에서는 이동 호스트가 이동 가능한 셀의 수가 최대 2개로 제한하여 FA에서의 메모리 요구량을 감소시키고, 핸드오프 중이라도 MH가 패킷을 계속 수신이 가능하도록 개선된 핸드오프 프로토콜을 설계한다. 기존의 방법과 비교 분석하여 본 논문에서 제시하는 개선된 핸드오프 방식이 우수하다는 것을 입증한다.

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Influence of Companion Planting on Microbial Compositions and Their Symbiotic Network in Pepper Continuous Cropping Soil

  • Jingxia Gao;Fengbao Zhang
    • Journal of Microbiology and Biotechnology
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    • 제33권6호
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    • pp.760-770
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    • 2023
  • Continuous cropping obstacles have become a serious factor restricting sustainable development in modern agriculture, while companion planting is one of the most common and effective methods for solving this problem. Here, we monitored the effects of companion planting on soil fertility and the microbial community distribution pattern in pepper monoculture and companion plantings. Soil microbial communities were analyzed using high-throughput sequencing technology. Companion plants included garlic (T1), oat (T2), cabbage (T3), celery (T4), and white clover (T5). The results showed that compared with the monoculture system, companion planting significantly increased the activities of soil urease (except for T5) and sucrase, but decreased catalase activity. In addition, T2 significantly improved microbial diversity (Shannon index) while T1 resulted in a decrease of bacterial OTUs and an increase of fungal OTUs. Companion planting also significantly changed soil microbial community structures and compositions. Correlation analysis showed that soil enzyme activities were closely correlated with bacterial and fungal community structures. Moreover, the companion system weakened the complexity of microbial networks. These findings indicated that companion plants can provide nutrition to microbes and weaken the competition among them, which offers a theoretical basis and data for further research into methods for reducing continuous cropping obstacles in agriculture.

Interaction Between Acid-Labile Subunit and Insulin-like Growth Factor Binding Protein 3 Expressed in Xenopus oocytes

  • Park, Kyung-Yi;Lee, Dong-Hee
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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    • pp.99-99
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    • 2001
  • The acid-labile subunit (ALS) associates with insulin-like growth factor (IGF)-I or -II and IGF binding protein-3 (IGFBP-3) to form a 150-kD complex in the circulation. This complex is thought to regulate the serum IGFs by restricting them in the vascular system and promotes their endocrine actions. Little is known about how ALS binds to IGFBP3, which connects the IGFs to ALS. Xenopus oocyte was utilized to study the function of ALS in assembling IGFs into the ternary complexes. Xenopus oocyte was shown to correctly translate in vitro transcribed mRNAs of ALS and IGFBP3. IGFBP3 and ALS mRNAs were injected in mixture and their products were immunoprecipitated by antisera against ALS and IGFBP3. Contrary to the traditional reports that ALS interacts only with IGF-bound IGFBP3, this study shows that ALS is capable of forming a binary complex with IGFBP3 in the absence of IGF. When cross-linked by disuccinimidyl substrate, band representing ALS-IGFBP3 complex was evident on the PAGE. IGFBP3 movement was monitored according to the distribution between the hemispheres. Following a localized translation in the vegetal hemisphere, IGFBP3 was shown to remain in the vegetal half in the presence of ALS. Different from wild type IGFBP3, however, mutant IGFBP3 freely diffused into the animal half despite the presence of ALS. Taken together, this study suggests that ALS may play an important role in sequestering IGFBP3 polypeptides via the intermolecular aggregation. Studies using this heterologous model will lead to a better understanding of the IGFBP3 and ALS assembling into the ternary structure and circulating IGF system.

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Disposal Pattern and Its Impact on Milk Production and Herd Size in Karan Fries and Karan Swiss Cows

  • Singh, M.K.;Gurnani, M.
    • Asian-Australasian Journal of Animal Sciences
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    • 제17권9호
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    • pp.1214-1218
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    • 2004
  • Data on 958 Karan Fries (KF) and 780 Karan Swiss (KS) cows, born during 1974 to 1992 at National Dairy Research Institute, Karnal were evaluated for causes of culling and their impact on milk performance and herd strength. Causes of culling were classified as voluntary culling (low milk yield) and involuntary culling (other than milk yield). The milk yield of cows was evaluated inretrospectively by estimating expected breeding value (EBV) on the basis of first lactation yield (FLY) and all available lactation yield (ALY). The culling rate of KF cows over the years varied from 10.89 (1988) to 33.92% (1991) with an overall average of 20.96% and in KS from 19.91 (1984) to 33.74% (1989) with an overall average of 25.01%. Reproductive disorders, teat and udder problems, low milk production, health and locomotive disorders were the major reasons of culling accounted respectively for 5.56, 4.97, 4.61, 3.18 and 2.24% of herd strength in KF cows. The corresponding causes of culling were 6.20, 6.26, 7.69, 1.49 and 2.67% of herd strength in KS cows. The involuntary culling of cows accounted for 82.4% in K F and 76.1% in KS cows of total culling. The average annual disposal rate in KF and KS was 26 and 30% whereas annual replacement rate was 24 and 26% respectively. The EBV of involuntary culled cows on the basis of FLY and ALY was 3,111 and 3,515 kg in KF; and 2,669 and 2,940 kg in KS cows respectively. The EBV of selected cows on the basis of FLY and ALY was 3,242 and 3,549 kg in KF and 2,893 and 3,245 kg in KS cows respectively. The average breeding value of involuntary culled cows was not significantly different from selected cows in both the herds. The high rate of involuntary culling of potential cows might be major factor responsible for declined performance and size in these herds. The results indicated that higher genetic gain (2.14% of herd average in KF and 3.49% of herd average in KS) could be obtained by restricting the involuntary culling (50% of total culling) through improved management practices and increasing replacement rate.

고속도로 상에서의 트럭교통 관리전략에 대한 영향 분석 (Analysis of Truck Management Strategies Impacts on Highway)

  • 양충헌;손영태
    • 한국도로학회논문집
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    • 제11권2호
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    • pp.175-184
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    • 2009
  • 본 연구에서는 미시적 교통 시뮬레이션 모형을 이용하여 대표적인 트럭관리전략 중에 하나인 트럭차로이용제한 전략의 대안을 다양한 효과 척도를 통해 평가하였다. 본 연구에서는 먼저 트럭차로 이용제한 전략이 어떠한 교통 조건, 기하구조 조건에서 긍정적인 효과를 보일 지에 대한 이해를 제공한다. 이를 위해 다양한 수준의 교통수요와 트럭비율을 주요 영향 인자로 설정하여 시뮬레이션 분석을 시행하였다. 결과적으로 본 전략이 효과를 보이기 위해서는 최대 교통류율이 1,300대/시/차로 이상 이거나 트럭차량이 전체 교통량에서 차지하는 비율이 적어도 10% 이상 되어야 한다는 것이다. 이러한 결과를 바탕으로 미국에서 가장 트럭교통량이 많은 곳 중에 하나는 710 고속도로 북쪽 방향 23마일 구간에 대해 시행 가능한 트럭차로 이용제한 대안 별로 영향 분석을 시행하였다. 결과적으로, 트럭차량이 많이 포함되어 교통이 혼잡할 때에는 편도 4차로 중 왼쪽 2차로에 대한 트럭통행을 제한한 경우 교통 흐름이 향상되고 차량 당 평균 연료 소비량이 가장 적은 것으로 나타났다. 이를 통해, 트럭차량 통행 제한차로수의 결정은 또한 이러한 전략의 성공에 중요한 역할을 하는 요소임을 증명하였다.

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아동의 개인적 변인과 환경적 변인이 또래에 의한 괴롭힘에 미치는 영향 (The Individual and Environmental Variables that Affect Victimization by Peer Harassment among Children)

  • 안재진;이경님
    • 가정과삶의질연구
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    • 제20권2호
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    • pp.9-20
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    • 2002
  • This study examined different individual and environmental factors that affect children's experience of harassment from their peers. For the individual variables, gender, behavioral problems, and self-esteem were included in the anal)'sis. For the family variables, mother's parenting style and the socio-economic status of parents were examined, and for the school variables, the supervision of the teacher and the attitudes of the classmates toward bullying were used. Two forms of peer harassment, the overt form and the relational form were examined in this study. The sample consisted of 520 fifth grade children. Statistics and methods used for the data analysis were Cronbach's alpha, factor analysis, frequency, percentage, means, standard deviation, Pearson's correlation, and multiple regression. Several major relationships were found from the analyses. First, the more the children tend to internalize behavioral problems and have lower self-esteem, the more likely they are to get victimized by overt and relational forms of harassment. Boys experience more overt harassment than girls. Second, the more the mother's parenting style is permissive-nonintervening, or rejecting-restricting, and the higher the father's social status is, the more likely the child is subjected to overt and relational forms of harassment. Third, the more the children feel that the teacher is paying attention to bullying, the less the children are subjected to the overt form of peer harassment. Fourth, children's internalizing behavioral problems, mother's permissiveness-nonintervention, children's self-esteem, children's gender, and the supervision of the teacher regarding bullying significantly affected the experience of overt forms of harassment. A twenty two percent variance in the victimization of an overt form was explained by those variables. Children's internalizing behavioral problems, mother's permissiveness-nonintervention, children's self-esteem, and mother's rejection-restriction significantly affected the experience of relational form of peers harassment. Twenty six percent of the variance in the relational form of victimization was explained by those variables.

최적 리콜보험상품 설계에 관한 연구 (The Design of Optimal Recall Insurance Product)

  • 김두철
    • 한국산학기술학회논문지
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    • 제3권4호
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    • pp.325-332
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    • 2002
  • 본 논문은 최적리콜보험계약의 설계와 관련된 논문의 survey이다. 리콜보험 뿐만이 아니라 최적보험계약을 만들기 위해서는 보험계약의 조건들이 내생적이라는 가정하에서 연구모형을 구축하고 분석의 과정에서는 보험구매를 위한 의사결정 원칙으로 기대효용이론, 비기대효용이론, 및 상태귀속적인 (state-dependent) 효용함수를 사용하였다. 어떠한 이론을 사용하더라도 최적보험의 조건들은 존재한다. 다만 계약조건에 관련되어서는 보험의 비용, 자기부담금, 보상한도액 등이 차이가 날 수 있다. 보험의 비용은 지급보험금과 선형, 오목형, 볼록형의 관계가 성립할 수 있으나 잠식비용과 고정비용의 존재를 인정하여야 한다. 이를 바탕으로 최적보험을 위한 비용 설계가 이루어져야 한다. 또한 전부보험이냐 일부보험이냐를 결정하는 자기부담금의 존재는 일률자기부담금형태와 점감식자기부담금형태가 가능하다. 자기부담금 수준의 결정과 관련하여 담보되는 모든 위험에 동일한 수준을 적용시킬 것인가 혹은 차별화시킬 것인가는 보험의 종류에 따라 달라질 수밖에 없다. 보상한도와 관련되어서는 특히 리콜보험에 있어서는 기업의 파산위험성이 상당히 존재하고 있으므로 계약당사자의 파산선고를 포함한 이익이 충분히 고려되어야 한다. 또한 제약조건으로는 불완전시장에 대한 이해를 필요로 하며 담보할 수 없는 배경위험의 존재에 대한 배려가 있어야 한다.

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유사 비디오 데이터 집합에서 효율적인 특성정보 프로파일 생성 기법 (Efficient Generation of a Feature Profile in a Set of Similar Video Data)

  • 박동철;장중혁;이원석
    • 정보처리학회논문지D
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    • 제12D권2호
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    • pp.219-232
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    • 2005
  • 산업정보사회가 발달함에 따라 다양한 형태의 비디오 데이터들이 여러 분야에서 대량으로 생성되고 있다. 이에 따라 이들의 가공을 통해 비디오에 나타난 의미 정보를 추출하려는 다양한 접근들이 시도되고 있으며, 근래 들어 데이터 마이닝 기법을 응용한 특성정보 프로파일 생성 방법에 대한 관심이 증대되고 있다. 그러나 기존의 연구에서는 시공간적으로 방대한 비디오 데이터의 특징으로 인해 해당 분야에 대한 연구가 소극적으로 진행되어왔다. 본 논문에서는 유사한 의미를 나타내는 비디오 데이터 집합에서 의미있는 지식을 추출하는 특성정보 프로파일 생성 기법을 제안한다. 더불어, 특성정보 프로파일 생성과정의 효율적인 수행을 위해서 다양한 추가 고려 사항을 제시한다. 전체 특성 정보들 중에서 주요 정보에만 집중함으로써 데이터 양을 감소시키는 방법, 잡음 요소를 제거하고 관심영역을 설정하여 데이터 양을 감소시키는 방법 및 동적인 영역에 가중치를 부여하여 추출된 정보의 정확도를 향상시키는 방법 등이 포함된다. 끝으로, 실험용 비디오 데이터에 대하여 논문에서 제안된 다양한 압축 방법을 적용하여 클러스터링을 수행하고 이를 통해 구해진 특성 정보 프로파일과 원본 비디오 데이터의 특성정보와 비교하여 본 논문에서 제시한 다양한 압축 알고리즘을 검증한다.

고구려인의 복식문화고찰-집안지역 고분벽화를 중심으로-

  • 양경애
    • 복식
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    • 제25권
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    • pp.183-199
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    • 1995
  • Among many different approaches of study of history of Kokuryo clothing culture, this study attempted to understand the costume by including political , militarial , economical , cultural , and religious aspects of Kokuryo society. It also included pictures in mural tumbs and old studies in Kokuryo costume. Clothing culture related to political life clearly differenciated social status by restricting styles and colors of clothes according to peoples social status. Generally people in high social status wore clothes with detailed decorations invariety of colors, and also used more fabrics than people in low social status. Costume was also affected by military life style that needed to meet the vigorous physical activities. High rank worriors wore iron scaled shielded clothes with red decoration on it which identified different ranks of the worriors. Economy also contributed it role to affect the clothing styles in Kokuryo. Based on old studies of costume, this study focused on people's life styles that included hunting and weaving . Hunting clothes were differentiated by decorating wit feathers . Jowoguan(조우관) is one of the examples. Since weaving was a major economic power or factor, silk and flax were very popular. People even used those fabrics to pay tax. Regarding cultural aspect , this study emphasized on song and dance wear along with active wear. Song and dance wear specially decorated with poka dots, however men and women wear were claryly distinguished. Unlike other clothes that were restricted in colors and styles, song and dance wear were decorated in variety of colors. Lastly this study presents religious aspects of Kokuryo costume . Monks wore black clothing (내의) that was influenced from China and the Western Regions(서역). To emphasize their religious power, Gods in the pictures of mural tumbs wore clothes with wings and feathers. God of fire and agriculture wore simple dresses without much decorations which represented simple life style of working class.

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