• 한국정보과학회논문지:소프트웨어및응용
• /
• 제31권8호
• /
• pp.999-1009
• /
• 2004

최근 생물정보 기술이 암 진단의 새로운 방법으로 관심을 모으고 있다. 다양한 기계학습 기법이 적용되어 우수한 결과를 얻고 있지만 의학 분야에서는 정확률이 높은 분류기뿐만 아니라 획득된 분류규칙을 사람이 분석하고 이해할 수 있어야 한다. 생물정보 기술에서 많이 이용되는 유전자 발현 데이터는 데이타 내에 수천 내지 수만의 변수가 존재하며, 직접 이들 사이의 복잡한 관계를 표현하고 이해하는 것은 매우 어렵다. 본 논문에서는 이러한 어려움을 극복하기 위해 유전자 발현 데이타에서 분류에 유용한 특징들을 추출하고 산술 연산자 기반 유전자 프로그래밍으로 암 분류규칙을 생성하는 방법을 제안한다. 림프종 유전자 발현 데이타에 대하여 실험하여 96.6%의 인식률을 얻었으며, 획득된 분류 규칙을 분석하여 다양한 지식을 발견할 수 있었다.

• 한국산학기술학회논문지
• /
• 제4권3호
• /
• pp.242-247
• /
• 2003

본 논문은 유전자 알고리듬을 이용하여 자동차 부품인 자동변속레버의 최적 설계 방법론에 대한 연구이다. 현재 업계에서의 자동변속레버는 구성 부품들을 순서적으로 설계하고 있으나, 본 연구에서는 구성 부품들의 설계 파라미터들을 동시에 고려하여 설계할 수 있는 새로운 방법론을 제안한다. 유전자 알고리듬 접근방법은 자동변속레버의 최적 설계 파라미터 집합을 결정하기 위해 적용된다. 본 연구에서는 자동변속레버의 구성 부품들로 구성된 제약조건하에 디텐트 스프링의 각 변위를 최소화하는 목적함수를 가지는 설계 문제를 모델링하였고, 유전자 알고리듬을 적용하여 최적 설계를 수행하였다.

• 한국생물정보학회:학술대회논문집
• /
• 한국생물정보시스템생물학회 2003년도 제2차 연례학술대회 발표논문집
• /
• pp.164-169
• /
• 2003

In this paper, we propose the integrated Bayesian network framework to reconstruct genetic regulatory networks from genome expression data. The proposed model overcomes the dimensionality problem of multivariate analysis by building coherent sub-networks from confined gene clusters and combining these networks via intermediary points. Gene Shaving algorithm is used to cluster genes that share a common function or co-regulation. Retrieved clusters incorporate prior biological knowledge such as Gene Ontology, pathway, and protein protein interaction information for extracting other related genes. With these extended gene list, system builds genetic sub-networks using Bayesian network with MDL score and Sparse Candidate algorithm. Identifying functional modules of genes is done by not only microarray data itself but also well-proved biological knowledge. This integrated approach can improve there liability of a network in that false relations due to the lack of data can be reduced. Another advantage is the decreased computational complexity by constrained gene sets. To evaluate the proposed system, S. Cerevisiae cell cycle data [1] is applied. The result analysis presents new hypotheses about novel genetic interactions as well as typical relationships known by previous researches [2].

• Journal of Plant Biotechnology
• /
• 제3권3호
• /
• pp.135-140
• /
• 2001

An Agrobacterium tumefaciens LBA4404 (harboring antisense OMT gene)-mediated transformation method has been developed for poplar (P.nigra x maximowiczii) using prolonging co-cultivation time. Explants on LT (longterm) were induced transgenic calli one month earlier than those from ST (short-term) co-cultivation and remained healthier on LT than ST. With this approach, LT method reduced time to produce transgenic calli. Shoots were successfully regenerated from transgenic calli on SIM (Shoot Induction Medium) and rooted well on the basal medium spontaneously. The presence of antisense OMT gene was verified both by PCR and Southern analysis. Each transgenic poplar was phenotypically indishtinguishable when compared with controls for their growth pattern, leaf morphologies and xylem coloration.

• Journal of Microbiology and Biotechnology
• /
• 제25권7호
• /
• pp.1101-1107
• /
• 2015

The role of CRE1 in a thermophilic fungus, Myceliophthora thermophila ATCC42464, was studied using RNA interference. In the cre1-silenced strain C88, the filter paper hydrolyzing activity and β-1,4-endoglucanase activity were 3.76-, and 1.31-fold higher, respectively, than those in the parental strain when the strains were cultured in inducing medium for 6 days. The activities of β-1,4-exoglucanase and cellobiase were 2.64-, and 5.59-fold higher, respectively, than those in the parental strain when the strains were cultured for 5 days. Quantitative reverse-transcription polymerase chain reaction showed that the gene expression of egl3, cbh1, and cbh2 was significantly increased in transformant C88 compared with the wild-type strain. Therefore, our findings suggest the feasibility of improving cellulase production by modifying the regulator expression, and an attractive approach to increasing the total cellulase productivity in thermophilic fungi.

• Journal of Communications and Networks
• /
• 제8권1호
• /
• pp.116-122
• /
• 2006

Most of the multimedia applications require strict quality of service (QoS) guarantee during the communication between a single source and multiple destinations. This gives rise to the need for an efficient QoS multicast routing strategy. Determination of such QoS-based optimal multicast routes basically leads to a multi-objective optimization problem, which is computationally intractable in polynomial time due to the uncertainty of resources in Internet. This paper describes a network model for researching the routing problem and proposes a new multicast tree selection algorithm based on genetic algorithms to simultaneously optimize multiple QoS parameters. The paper mainly presents a QoS multicast routing algorithm based on genetic algorithm (QMRGA). The QMRGA can also optimize the network resources such as bandwidth and delay, and can converge to the optimal or near-optimal solution within few iterations, even for the networks environment with uncertain parameters. The incremental rate of computational cost can close to polynomial and is less than exponential rate. The performance measures of the QMRGA are evaluated using simulations. The simulation results show that this approach has fast convergence speed and high reliability. It can meet the real-time requirement in multimedia communication networks.

• 한국시뮬레이션학회:학술대회논문집
• /
• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
• /
• pp.263-268
• /
• 2001

In this paper, we present a new heuristic algorithm fur buffer allocation in FMS (Flexible Manufacturing System). It is conducted by using a genetic algorithm and simulation. First, we model the system by using a simulation software, \"Arena\". Then, we apply a genetic algorithm to achieve an optimal solution. VBA blocks, which are kinds of add-in functions in Arena, are used to connect Arena with the genetic algorithm. The system being modeled has seven workstations, one loading/unloading station, and three AGVs (Automated Guided Vehicle). Also it contains three products, which each have their own machining order and processing times. We experimented with two kinds of buffer allocation problems with a proposed heuristic algorithm, and we will suggest a simple heuristic approach based on processing times and workloads to validate our proposed algorithm. The first experiment is to find a buffer profile to achieve the maximum throughput using a finite number of buffers. The second experiment is to find the minimum number of buffers to achieve the desired throughput. End of this paper, we compare the result of a proposed algorithm with the result of a simple buffer allocation heuristic based on processing times and workloads. We show that the proposed algorithm increase the throughput by 7.2%.t by 7.2%.

• 한국간호교육학회지
• /
• 제19권4호
• /
• pp.675-683
• /
• 2013

Purpose: Nineteen articles were analyzed to gather opinions and nursing implications about NIPT recently launched. Methods: Nineteen articles were selected from EBSCO (eBook business collection), Google Scholar, and two Korean academic d-bases with key words 'prenatal screening testing', 'prenatal genetic diagnostic testing', NIPT or 'cell free DNA (cfDNA)'. Authors developed a framework for analyzing the 19 articles including opinions and suggestions for future implications. Results: Eleven articles written by the first author affiliated with medicine or genetics, viewed NIPT as promising because of safety, accuracy, early detectability and cost effectiveness. Articles written by journalists or authors affiliated with history and ethics were concerned with the possible risk of ELSI (ethical, legal, social issues), erratic interpretation of test results, and lack of genetic counseling service. Conclusion: With consideration of Korean clinical, and legal circumstances, not only pregnant women and families but also health professionals must prepare for clinical NIPT implications including updating prenatal genetic testing, counseling services, protecting ELSI and amulticultural team approach.

• 통합자연과학논문집
• /
• 제11권2호
• /
• pp.121-129
• /
• 2018

CXCR6 is a major target in drug design as it is a determinant receptor in many diseases like AIDS, Type I Diabetes, some cancer types, atherosclerosis, tumor formation, liver disease and steatohepatitis. In this study, we propose the active site residues of CXCR6 molecule. We employed homology modelling and molecular docking approach to generate the 3D structure for CXCR6 and to explore its interaction between the antagonists and agonists. 3D models were generated using 14 different templates having high sequence identity with CXCR6. Surflex docking studies using pyridine and pyrimidine derivatives enabled the analysis of the binding site and finding of the important residues involved in binding. 3D structure of CXCL16, a natural ligand for CXCR6, was modelled using PHYRE and protein - protein docking was performed using ClusPro. The residues which were found to be crucial in interaction with the ligand are THR110, PHE113, TYR114, GLN160, GLN195, CYS251 and SER255. This study can be used as a guide for therapeutic studies of human CXCR6.

• 한국해양공학회지
• /
• 제18권5호
• /
• pp.29-35
• /
• 2004

A new approach, referred to as a successive zooming genetic algorithm (SZGA), is proposed for identifying a global solution, using continuous zooming factors for optimization problems. In order to improve the local fine-tuning of the GA, we introduced a new method whereby the search space is zoomed around the design variable with the best fitness per 100 generation, resulting in an improvement of the convergence. Furthermore, the reliability of the optimized solution is determined based on the theory of probability, and the parameter used for the successive zooming method is optimized. With parameter optimization, we can eliminate the time allocated for deciding parameters used in SZGA. To demonstrate the superiority of the proposed theory, we tested for the minimization of a multiple function, as well as simple functions. After testing, we applied the parameter optimization to a truss problem and wicket gate servomotor optimization. Then, the proposed algorithm identifies a more exact optimum value than the standard genetic algorithm.