• 제목/요약/키워드: Genetic Approach

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Lipooligosaccharide biosynthesis genes of nontypable Haemophilus influenzae 2019

  • Lee, Na-Gyong;Melvin G. Sunshine;Jeffery J. Engstrom;Bradford W. Gibson;Michael A. Apicella
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1996년도 제4회 추계심포지움
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    • pp.65-73
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    • 1996
  • LPS/LOS, the compound found only in gram-negative bacterial outer membrane, plays important roles in bacterial maintenance as well as its pathogenesis. We isolated and characterized several genes required for NTHi 2019 LOS biosynthesis, which encode enzymes required for sugar substrate synthesis or the transfer of substrates to receptor molecules. The htrB gene, however, appears to have more complex role. It has acryltransferase activity as well as various other activity, which may control regulation of LOS biosynthesis as well as its pathogenicity. Evidences supporting the latter come from the observations that the lipid A of the B29 induced significantly less TNF ${\alpha}$ from macrophages than that of the wild type LOS (unpublished data). H. influenzae A2-htrB mutant strain was also significantly less invasive than the wild type strain. The structural similarities of the enterobacterial LPS and the Haemophilus LOS enabled us to isolate the NTHi 2019 genes involved in LOS biosynthesis genes by using the S. typhimurium LPS deep core mutants. While a similar approach has been used for E. coli, this technique for selection of an LPS phenotype has not been applied to nonenterobacterial species. The difficulties inherent in the molecular manipulation of organism such as Neisseria and Haemophilus species make this approach particularly attractive in the identification and cloning LOS genes. Studies on genetic features of LPS/LOS biosynthesis would be useful for understanding bacterial pathogenesis as well as for developing vaccines for these gram-negative pathogenic bacteria.

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인체 임파양세포에서 $G_2$기 염색체의 방사선 감수성 (Radiation Induced $G_2$ Chromatid Break and Repair Kinetics in Human Lymphoblastoid Cells)

  • 성진실
    • Radiation Oncology Journal
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    • 제11권2호
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    • pp.193-203
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    • 1993
  • In understanding radiosensitivity a new concept of inherent radiosensitivity based on individuality and heterogeneity within a population has recently been explored. There has been some discussion of possible mechanism underlying differences in radiosensitivity between cells. Ataxia telangiectasia (AT), a rare autosomal recessive genetic disorder, is characterized by hypersensitivity to ionizing radiation and other DNA damaging agents at the cellular level. There have been a lot of efforts to describe the cause of this hypersensitivity to radiation. At the cellular level, chromosome repair kinetics study would be an appropriate approach. The purpose of this study was to better understand radiosensitivity En an approach to investigate kinetics of induction and repair of $G_2$ chromatic bleaks using normal, AT heterozygous (ATH), and AT homozygous lymphoblastoid cell lines. In an attempt to estimate initial damage, $9-{\beta}-D-arabinosyl-2-fluoroadenine,$ an inhibitor of DNA synthesis and repair, was used in this study. It was found from this study that radiation induces higher chromatid breaks in AT than in normal and ATH cells. There was no significant differences of initial chromatid breaks between normal and ATH cells. Repair kinetics was the same for all. So the higher level of breaks in AT $G_2$ cells is thought to be a reflection of the increased initial damage. The amount of initial damage correlated well with survival fraction at 2 Gy of cell survival curve following radiation. Therefore, the difference of radiosensitivity in terms of $G_2$ chromosomal sensitivity is thought to result from the difference of initial damage.

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주문생산을 위한 APS 와 효율적 구매의 통합모델 (Integrated Supply Chain Model of Advanced Planning and Scheduling (APS) and Efficient Purchasing for Make-To-Order Production)

  • 정찬석;이영해
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 2002년도 춘계공동학술대회
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    • pp.449-455
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    • 2002
  • This paper considers that advanced planning and scheduling (APS) in manufacturing and the efficient purchasing where each customer order has its due date and multi-suppliers exit We present a Make-To­Order Supply Chan (MTOSC) model of efficient purchasing process from multi-suppliers and APS with outsourcing in a supply chain, which requires the absolute due date and minimized total cost. Our research has included two states. One is for efficient purchasing from suppliers: (a) selection of suppliers for required parts; (b) optimum part lead­time of selected suppliers. Supplier selection process has received considerable attention in the business­management literature. Determining suitable suppliers in the supply chain has become a key strategic consideration. However, the nature of these decisions usually is complex and unstructured. These influence factors can be divided into quantitative and qualitative factors. In the first level, linguistic values are used to assess the ratings for the qualitative factors such as profitability, relationship closeness and quality. In the second level a MTOSC model determines the solutions (supplier selection and order quantity) by considering quantitative factors such as part unit price, supplier's lead-time, and storage cost, etc. The other is for APS: (a) selection of the best machine for each operation; (b) deciding sequence of operations; (c) picking out the operations to be outsourcing; and (d) minimizing makespan under the due date of each customer's order. To solve the model, a genetic algorithm (GA)-based heuristic approach is developed. From the numerical experiments, GA­based approach could efficiently solve the proposed model, and show the best process plan and schedule for all customers' orders.

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전체 공급망 수익성 개선을 위한 게임이론 기반의 수요 할당 메커니즘의 비교 연구 (Comparative Analysis of Game-Theoretic Demand Allocation for Enhancing Profitability of Whole Supply Chain)

  • 신광섭
    • 한국전자거래학회지
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    • 제19권1호
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    • pp.43-61
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    • 2014
  • 본 연구는 공급망 운영에서 가장 기본적이고 필수적인 연구 분야인 공급자의 선정과 수요의 할당 문제를 해결하기 위한 방법으로 게임이론을 적용하였다. 특히, 가장 보편적으로 사용되고 있는 점진적 역경매 메커니즘을 비율적 형평성을 보장하는 구매 게임 방식과 공급망 전체 운영의 수익성이라는 관점에서 비교 분석하였다. 서로 다른 두 메커니즘의 정교한 비교 분석을 위한 전체 알고리즘을 제시하였으며, 구매게임을 이용한 공급자 선정 및 주문 배분의 최적해는 유전자 알고리즘을 통해 도출하였다. 전체 공급망의 수익성은 공급자와 구매자의 수익함수와 수익-비용 비율을 통해 평가하였다. 실제 현실의 공급망을 단순화한 모형을 바탕으로 본 연구에서 제안하는 방법이 전체 공급망의 수익성을 어떻게 향상시킬 수 있는 지를 간단한 실험과 통계 분석을 통해 설명하였다. 이를 통해 구매게임의 해가 역경매 방식에 비해 구매자의 수익성 감소를 통해 공급자와 구매자를 모두 포함하는 공급망 전체의 수익성을 크게 향상시킬 수 있음을 보였다.

OPF with Environmental Constraints with Multi Shunt Dynamic Controllers using Decomposed Parallel GA: Application to the Algerian Network

  • Mahdad, B.;Bouktir, T.;Srairi, K.
    • Journal of Electrical Engineering and Technology
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    • 제4권1호
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    • pp.55-65
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    • 2009
  • Due to the rapid increase of electricity demand, consideration of environmental constraints in optimal power flow (OPF) problems is increasingly important. In Algeria, up to 90% of electricity is produced by thermal generators (vapor, gas). In order to keep the emission of gaseous pollutants like sulfur dioxide (SO2) and Nitrogen (NO2) under the admissible ecological limits, many conventional and global optimization methods have been proposed to study the trade-off relation between fuel cost and emissions. This paper presents an efficient decomposed Parallel GA to solve the multi-objective environmental/economic dispatch problem. At the decomposed stage the length of the original chromosome is reduced successively and adapted to the topology of the new partition. Two subproblems are proposed: the first subproblem is related to the active power planning to minimize the total fuel cost, and the second subproblem is a reactive power planning design based in practical rules to make fine corrections to the voltage deviation and reactive power violation using a specified number of shunt dynamic compensators named Static Var Compensators (SVC). To validate the robustness of the proposed approach, the algorithm proposed was tested on the Algerian 59-bus network test and compared with conventional methods and with global optimization methods (GA, FGA, and ACO). The results show that the approach proposed can converge to the near solution and obtain a competitive solution at a critical situation and within a reasonable time.

출생 전 생명에 대한 생명윤리적 고찰 (Bioethical Deliberation of a Human Life before Birth)

  • 최경석
    • 의료법학
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    • 제10권1호
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    • pp.11-38
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    • 2009
  • "Bioethics" may have various meanings depending on its roles. It may mean professional ethics for scientists and physicians, etc. It may also mean an academic discipline using interdisciplinary approach as well as a philosophical or a legal approach. "Bioethics" as an interdisciplinary study should often deal with public policy on bioethical issues. I call this role bioethics as a study of bioethics policy, which has to be developed as a new discipline. From this perspective, I deal with bioethical issues relevant to a human life before birth. There are various and often conflicting arguments about the moral status of a human life before birth such as the fertilization argument, the argument of genetic identity, so-called the "14 days" argument focusing on the formation of primitive streak, the argument of sentient being, and Michael Sandle's argument of an embryo as a being between a thing and a person. I argue that each of them is reasonable. Thus we are faced with reasonable disagreement on the views over whether a human life before birth has the same right to life as that of a person or whether right to life may be considered to be a matter of degree. If we acknowledge reasonable disagreement, as John Rawls pointed out, we should tolerate the views from ours in a plural society. Therefore, we cannot help making a policy that allows abortion and embryonic research with some limitations. When we say a certain act is morally permissible, "moral permissibility" does not mean that the act is morally right for all. Rather it means that the act cannot help being morally allowed for some persons although the others do not believe its moral rightness because they cannot right now rationally persuade others to accept their view.

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Cost-based design of residential steel roof systems: A case study

  • Rajan, S.D.;Mobasher, B.;Chen, S.Y.;Young, C.
    • Structural Engineering and Mechanics
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    • 제8권2호
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    • pp.165-180
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    • 1999
  • The cost effectiveness of using steel roof systems for residential buildings is becoming increasingly apparent with the decrease in manufacturing cost of steel components, reliability and efficiency in construction practices, and the economic and environmental concerns. While steel has been one of the primary materials for structural systems, it is only recently that its use for residential buildings is being explored. A comprehensive system for the design of residential steel roof truss systems is presented. In the first stage of the research the design curves obtained from the AISI-LRFD code for the manufactured cross-sections were verified experimentally. Components of the truss systems were tested in order to determine their member properties when subjected to axial force and bending moments. In addition, the experiments were simulated using finite element analysis to provide an additional source of verification. The second stage of the research involved the development of an integrated design approach that would automatically design a lowest cost roof truss given minimal input. A modified genetic algorithm was used to handle sizing, shape and topology variables in the design problem. The developed methodology was implemented in a software system for the purpose of designing the lowest cost truss that would meet the AISI code provisions and construction requirements given the input parameters. The third stage of the research involved full-scale testing of a typical residential steel roof designed using the developed software system. The full scale testing established the factor of safety while validating the analysis and design procedures. Evaluation of the test results indicates that designs using the present approach provide a structure with enough reserve strength to perform as predicted and are very economical.

Multi-objective optimization of stormwater pipe networks and on-line stormwater treatment devices in an ultra-urban setting

  • Kim, Jin Hwi;Lee, Dong Hoon;Kang, Joo-Hyon
    • Membrane and Water Treatment
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    • 제10권1호
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    • pp.75-82
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    • 2019
  • In a highly urbanized area, land availability is limited for the installation of space consuming stormwater systems for best management practices (BMPs), leading to the consideration of underground stormwater treatment devices connected to the stormwater pipe system. The configuration of a stormwater pipe network determines the hydrological and pollutant transport characteristics of the stormwater discharged through the pipe network, and thus should be an important design consideration for effective management of stormwater quantity and quality. This article presents a multi-objective optimization approach for designing a stormwater pipe network with on-line stormwater treatment devices to achieve an optimal trade-off between the total installation cost and the annual removal efficiency of total suspended solids (TSS). The Non-dominated Sorted Genetic Algorithm-II (NSGA-II) was adapted to solve the multi-objective optimization problem. The study site used to demonstrate the developed approach was a commercial area that has an existing pipe network with eight outfalls into an adjacent stream in Yongin City, South Korea. The stormwater management model (SWMM) was calibrated based on the data obtained from a subcatchment within the study area and was further used to simulate the flow rates and TSS discharge rates through a given pipe network for the entire study area. In the simulation, an underground stormwater treatment device was assumed to be installed at each outfall and sized proportional to the average flow rate at the outfall. The total installation cost for the pipes and underground devices was estimated based on empirical formulas using the flow rates and TSS discharge rates simulated by the SWMM. In the demonstration example, the installation cost could be reduced by up to 9% while the annual TSS removal efficiency could be increased by 4% compared to the original pipe network configuration. The annual TSS removal efficiency was relatively insensitive to the total installation cost in the Pareto-optimal solutions of the pipe network design. The results suggested that the installation cost of the pipes and stormwater treatment devices can be substantially reduced without significantly compromising the pollutant removal efficiency when the pipe network is optimally designed.

마이크로어레이 분석기법의 임상적용에 관한 연구 (Medical Implementation of Microarray Technology)

  • 강지언
    • 대한임상검사과학회지
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    • 제52권4호
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    • pp.310-316
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    • 2020
  • 마이크로어레이 진단 기법의 발달은 세포유전학적 관점에서, 다양한 종류의 유전학적 질병과 관련하여 새로운 정보를 제공하고, 질병에 대한 기본적인 통찰력을 제공하는데 매우 중요한 역할을 제공하고 있다. 그동안 많은 연구들에서, 마이크로어레이 기술을 활용한 인간 게놈의 유동성과 다양성을 입증해 주었으며, 게놈의 취약성을 식별하기 위한 보다 정확한 진단기법과 적절한 임상 관리 방법을 효율적으로 제공해 왔다. 앞으로 다양한 유전과 관련된 질병에 기존 세포유전학적 방법을 자동화된 마이크로어레이 방법으로 전환한다면, 보다 효율적인 방법으로 질병을 진단하고, 정확성을 향상시키며, 유전자 배열의 암호화 및 복잡한 특성을 밝히는데 매우 중요한 역할을 할 것으로 생각된다. 또한 이 분석 기법을 활용하여 게놈과 인간의 건강, 질병과의 관계를 분석하여 다양한 정보를 미리 제공하여 질병을 예방하고, 질병의 진단 및 치료에도 도움이 될 수 있는 새로운 혁명을 일으킬 수 있을 것으로 기대된다.

다양한 지표모형을 활용한 토양수분 예측 성능 평가 연구 (A Study on Soil Moisture Estimates Performance Using Various Land Surface Models)

  • 장예근;신승훈;이태화;장원석;신용철;장근창;천정화;김종건
    • 한국농공학회논문집
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    • 제64권1호
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    • pp.79-89
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    • 2022
  • Soil moisture is significantly related to crop growth and plays an important role in irrigation management. To predict soil moisture, various process-based model has been developed and used in the world. Various models (Land surface model) may have different performance depending on the model parameters and structures that causes the different model output for the same modeling condition. In this study, the three land surface models (Noah Land Surface Model, Soil Water Atmosphere Plant, Community Land Model) were used to compare the model performance (soil moisture prediction) and develop the multi-model simulation. At first, the genetic algorithm was used to estimate the optimal soil parameters for each model, and the parameters were used to predict soil moisture in the study area. Then, we used the multi-model approach based on Bayesian model averaging (BMA). The results derived from this approach showed a better match to the measurements than the results from the original single land surface model. In addition, identifying the strengths and weaknesses of the single model and utilizing multi-model methods can help to increase the accuracy of soil moisture prediction.