• Title/Summary/Keyword: center selection

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The Role of Dendritic Cells in Central Tolerance

  • Oh, Jaehak;Shin, Jeoung-Sook
    • IMMUNE NETWORK
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    • v.15 no.3
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    • pp.111-120
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    • 2015
  • Dendritic cells (DCs) play a significant role in establishing self-tolerance through their ability to present self-antigens to developing T cells in the thymus. DCs are predominantly localized in the medullary region of thymus and present a broad range of self-antigens, which include tissue-restricted antigens expressed and transferred from medullary thymic epithelial cells, circulating antigens directly captured by thymic DCs through coticomedullary junction blood vessels, and peripheral tissue antigens captured and transported by peripheral tissue DCs homing to the thymus. When antigen-presenting DCs make a high affinity interaction with antigen-specific thymocytes, this interaction drives the interacting thymocytes to death, a process often referred to as negative selection, which fundamentally blocks the self-reactive thymocytes from differentiating into mature T cells. Alternatively, the interacting thymocytes differentiate into the regulatory T (Treg) cells, a distinct T cell subset with potent immune suppressive activities. The specific mechanisms by which thymic DCs differentiate Treg cells have been proposed by several laboratories. Here, we review the literatures that elucidate the contribution of thymic DCs to negative selection and Treg cell differentiation, and discusses its potential mechanisms and future directions.

An Analysis of the Hazardous Highway Segments Using Continuous Risk Profile Method (고속도로 사고잦은 지점 분석방법 연구)

  • Lee, Soo-Il;Yu, Jun-Seok
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.180-185
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    • 2010
  • We have to develop more correct and systematic way to choose Hazardous Highway Segments. In this research, we applied CRP(Continuous Risk Profile) technique which developed by UC Berkeley Traffic Safety Center in year of 2007, and can analyze yearly dangerous level tendency of continuity in the route of main road that is under California Department of Transportation(Caltrans). We changed standard of CRP to suit in Korean circumstance with consideration in radius of curve and traffic volume. For the verification by actual accident data, we embodiment the CRP by using the data from total of 587 case of accident in latest 10 years in Gyeong-Bu Highways, the amount of 56km. Finally, the effectiveness of technique in this research has been verified by obtained same result with current method for Hazardous Highway Segments. In addition, when calculating the Hazardous Highway Segments with technique that presented in this research we obtained following statements. First, identified dangerous level of continuity in the route by using CRP. Second, Accurate of Actual Hazardous Highway Segments selection has been developed by using last 10 year's data and profile making which provide simplicity analyze of Tendency. Third, after reforming the way of selection, effective range has been wider than former selection and it gives advantage for the policy side.

Analytical Approach for Scalable Feature Selection (확장 가능한 요소선택방법을 위한 분석적 접근)

  • Yang, Jae-Kyung;Lee, Tae-Han
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.29 no.2
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    • pp.75-82
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    • 2006
  • 본 연구에서 조합 최적화(Combinatorial Optimization) 이론에 바탕을 두고 있는 네스티드 분할(Nested Partition, 이하 NP) 방법을 이용한 최적화 기탄 요소선택 방법(Feature Selection)을 제안한다. 이 새로운 방법은 좋은 요소 부분집합을 찾는 휴리스틱 탐색 절차를 채용하고 있으며 데이터의 인스턴스(Instances 또는 Records)의 무작위 추출(Random Sampling)을 이용하여 이 요소선택 방법의 처리시간 관점에서의 성능을 항상 시키고자 한다. 이 새로운 접근 방법은 처리시간 향상을 위해 2단계 샘플링 방법을 채용하여 근접 최적해로의 수렴(Convergence)을 보장하는 샘플 사이즈를 결정한다. 이는 앨고리듬이 유한한 시간내에 끝이날 때 최종 요소 부분집합 해의 질(Qualtiy)에 관한 정확한 설명을 할 수 있는 이론적인 배경을 제시한다. 중요 결과를 예시하기 위해서 다양한 형태의 다섯 개의 데이터 셋을 이용하였으며 다섯 번의 반복 실험을 통한 실험 결과가 제시되며, 이 새로운 접근 방법이 기존의 단순 네스티드 분할 방법 기반의 요소선택 방법보다 처리시간 관점에서 더욱 효율적임을 보여준다.

Replacement Algorithm Selection Mechanism Considering File Size for Web Cache Server

  • Sontisiri, Tanasun;Sopechoke, Pawin;Thipchaksurat, Sakchai;Varakulsiripunth, Ruttikorn
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1084-1089
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    • 2004
  • This paper describes the improvement of web cache server by scoping in replacement algorithm of data which are collected from the clients. We have found that each replacement algorithm is suitable for each type of data in the web pages. Therefore, we introduce the mechanism to select the replacement algorithm depending on the size of data called the Replacement Algorithm Selection Mechanism (RASM). RASM allows the web cache server to have the suitable replacement algorithm for each type of data. As the result, the byte hit ratio of web cache server can be increased and the congestion in the network can be alleviated.

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Selection of Appropriate Endotracheal Tube in Wild Birds

  • Jang, Jin-Ho;Park, Young-Seok;Kim, Hee-Jong;Kim, Hye Kwon;Yun, Young-Min
    • Journal of Veterinary Clinics
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    • v.35 no.5
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    • pp.184-189
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    • 2018
  • Wild birds rescued for various reasons are injured and admitted to a wild animal rescue center. With the case of collision with cars, buildings and wires on a power pole, most wild birds are severely traumatized or get fractured, which need intensive veterinary treatment. In general, inhalation anesthesia to wild birds is the best choice for the medical and surgical procedure, and intubation is recommended for the stable anesthesia. Although the certain size of an endotracheal tube can be chosen depending on the size and morphology of the bird, there are a few standardized guidelines. Therefore, the optimal endotracheal size of the rescued 162 individual birds of 41 species for four years from March 2014 to December 2017 was investigated and sorted empirically, suggesting possibly the appropriate endotracheal sizes for diverse avian species. It may provide practical information data for wildlife veterinarians to select the size of an endotracheal tube according to the size of the domestic wild bird species, especially during surgery in the emergency cases.

Effective Feature Selection Model for Network Data Modeling (네트워크 데이터 모델링을 위한 효과적인 성분 선택)

  • Kim, Ho-In;Cho, Jae-Ik;Lee, In-Yong;Moon, Jong-Sub
    • Journal of Broadcast Engineering
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    • v.13 no.1
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    • pp.92-98
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    • 2008
  • Network data modeling is a essential research for the evaluation for intrusion detection systems performance, network modeling and methods for analyzing network data. In network data modeling, real data from the network must be analyzed and the modeled data must be efficiently composed to reflect a sufficient amount of the original data. In this parer the useful elements of real network data were quantified from packets captured from a huge network. Futhermore, a statistical analysis method was used to find the most effective element for efficiently classifying the modeled data.

A Study on the Site Selection of Ship-Instrument Distribution Center (선용품 유통센터 입지선정에 관한 연구)

  • Kim Woong-Sub;Shin Jae-Yeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2006.06b
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    • pp.411-415
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    • 2006
  • The Circumstances surrounding world ports have changed rapidly and port competition to attract more a client to each other. then, In the future, only a few ports will be survive. Therefore, industrail that concern with ports is very important position. if it revitalize, port must have international competitiveness. The purpose of this paper is as follow. The first is to investigate ship-instrument industrial with theoretical background and distribution cycle. And then, to determine the location' ship-instrument distribution center' in the Busan Port. The second is to analyze to proposal location for distribution center.

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Genetic Improvement of Some Traits in Four Strains of Silkworm, Bombyx mori L.

  • Moghaddam S. H. Hosseini;Jomeh K. N. Emam;Mirhosseini S. Z.;Gholamy M. R.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.10 no.2
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    • pp.95-99
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    • 2005
  • A breeding plan was carried out on four commercial strains of silkworm (Bombyx mori L.) 101, 102, 103 and 104 to improve some important traits. Genetic gain or response to selection $({\Delta}G)$, heritability of cocoon shell weight (CSW) and specific combining ability effects were estimated to determine the strains that can be improved. Strain 101 had lowest heritabitity, ${\Delta}G$ and viability. Strain 102 was acceptable in selection response but its viability was low. Therefore these two strains were not suitable for more selection. As a result, only lines 103 and 104 were chosen for further improvement. Intra population selection based on independent culling level method practiced from third to sixth generation for both productive and viability traits simultaneously. While CSW and CW had increasingly enhanced during primary generations, they went slightly up after third generation. According to negative genetic correlation, viability decreased during primary generations, but after third generation that paid attention to balanced development of both productive and viability traits, viability increased so that the pupation rate reached to $91\%$ in 103 and $97\%$ in 104 for last generation $(G_8)$.

A Study on Developing a CER Using Production Cost Data in Korean Maneuver Weapon System (한국형 기동무기체계 양산비 비용추정관계식 개발에 관한 연구)

  • Lee, Doo-Hyun;Kim, Gak-Gyu
    • Journal of the Korean Operations Research and Management Science Society
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    • v.39 no.3
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    • pp.51-61
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    • 2014
  • In this paper, we deal with developing a cost estimation relationships (CER) for Korean maneuverable weapons systems using historical production cost. To develop the CER, we collected the historical data of the production cost of four tanks and five armored vehicles. We also analyzed the Required Operational Capability (ROC) of the weapons systems and chose cost drivers that can compare operational capabilities of the weapons systems We used Forward selection, Backward selection, Stepwise Regression and $R^2$ selection as the cost drivers which have the greatest influence with the dependent variables. And we used Principle Component Regression, Robust Regression and Weighted Regression to deal with multicollinearity and outlier among the data to develop a more appropriate CER. As a result, we were able to develop a production cost CER for Korean maneuverable weapons systems that have the lowest cost errors. Thus, this research is meaningful in terms of developing a CER based on Korean original cost data without foreign data and these methods will contribute to developing a Korean cost analysis program in the future.

Use of In Vivo and In Vitro Systems to Select Leishmania amazonensis Expressing Green Fluorescent Protein

  • Costa, Solange Dos Santos;Golim, Marjorie De Assis;Bergmann, Bartira Rossi;Costa, Fabio Trindade Maranhao;Giorgio, Selma
    • Parasites, Hosts and Diseases
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    • v.49 no.4
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    • pp.357-364
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    • 2011
  • Various Leishmania species were engineered with green fluorescent protein (GFP) using episomal vectors that encoded an antibiotic resistance gene, such as aminoglycoside geneticin sulphate (G418). Most reports of GFP-Leishmania have used the flagellated extracellular promastigote, the stage of parasite detected in the midgut of the sandfly vector; fewer studies have been performed with amastigotes, the stage of parasite detected in mammals. In this study, comparisons were made regarding the efficiency for in vitro G418 selection of GFP-Leishmania amazonensis promastigotes and amastigotes and the use of in vivo G418 selection. The GFP-promastigotes retained episomal plasmid for a prolonged period and G418 treatment was necessary and efficient for in vitro selection. In contrast, GFP-amastigotes showed low retention of the episomal plasmid in the absence of G418 selection and low sensitivity to antibiotics in vitro. The use of protocols for G418 selection using infected BALB/c mice also indicated low sensitivity to antibiotics against amastigotes in cutaneous lesions.