• 제목/요약/키워드: genetic system

검색결과 3,403건 처리시간 0.033초

Failure estimation of the composite laminates using machine learning techniques

  • Serban, Alexandru
    • Steel and Composite Structures
    • /
    • 제25권6호
    • /
    • pp.663-670
    • /
    • 2017
  • The problem of layup optimization of the composite laminates involves a very complex multidimensional solution space which is usually non-exhaustively explored using different heuristic computational methods such as genetic algorithms (GA). To ensure the convergence to the global optimum of the applied heuristic during the optimization process it is necessary to evaluate a lot of layup configurations. As a consequence the analysis of an individual layup configuration should be fast enough to maintain the convergence time range to an acceptable level. On the other hand the mechanical behavior analysis of composite laminates for any geometry and boundary condition is very convoluted and is performed by computational expensive numerical tools such as finite element analysis (FEA). In this respect some studies propose very fast FEA models used in layup optimization. However, the lower bound of the execution time of FEA models is determined by the global linear system solving which in some complex applications can be unacceptable. Moreover, in some situation it may be highly preferred to decrease the optimization time with the cost of a small reduction in the analysis accuracy. In this paper we explore some machine learning techniques in order to estimate the failure of a layup configuration. The estimated response can be qualitative (the configuration fails or not) or quantitative (the value of the failure factor). The procedure consists of generating a population of random observations (configurations) spread across solution space and evaluating using a FEA model. The machine learning method is then trained using this population and the trained model is then used to estimate failure in the optimization process. The results obtained are very promising as illustrated with an example where the misclassification rate of the qualitative response is smaller than 2%.

도메인 온톨로지를 이용한 검색 시스템 설계 및 구현 (Design and Implementation of Search System Using Domain Ontology)

  • 강래구;정채영
    • 한국정보통신학회논문지
    • /
    • 제11권7호
    • /
    • pp.1318-1324
    • /
    • 2007
  • 지금까지의 상품 검색 방법으로는 찾고자하는 정보를 검색할 때 주로 단어의 빈도수나 어휘 정보를 이용하는 키워드 기반의 검색이 주로 쓰이고 있었다. 키워드 기반의 검색에서는 사용자의 질의와 관련이 없는 문서들까지도 같은 결과로 나타내 주고 이로 인해 사용자는 제시된 결과를 한번 더 수동적으로 검색해야하는 부담을 않게 되었다. 이러한 문제점을 해결하기 위해 온톨로지가 대두되었다. 본 논문에서는 온톨로지를 이용한 상품 검색 시스템을 직접 구축하여 분류별 검색을 통해 얼마나 정확한 검색을 하는지 실험하였다. 실험을 위해 전국적으로 On/Off라인 할인점을 운영 중에 있는 A할인점의 상품 데이터 약 40,000여개를 데이터 베이스로 구축하였고 User Interface 개발환경은 JSP와 PowerBuilder9.0을 사용하여 검색 시스템을 개발하여 실험하였다. 그 결과 본 논문에서 제안하고 설계한 상품 도메인 온톨로지를 이용한 검색 방법이 기존의 기반의 검색 방법보다 우수한 결과를 나타내고 있음을 입증하였다.

Different Physiological Response to Salt in Salt Tolerant Rice Mutants Induced by Gamma-Mutagenesis

  • Jang, Duk-Soo;Song, Mira;Kim, Sun-hee;Kim, Jin-Baek;Kim, Sang Hoon;Ha, Bo-Keun;Kang, Si-Yong;Kim, Wook;Kim, Dong Sub
    • 방사선산업학회지
    • /
    • 제5권3호
    • /
    • pp.259-266
    • /
    • 2011
  • When plants undergo stress, Reactive oxygen species (ROS) which remove bad elements such as mildew and virus is activated in plant body. However, if ROS is excessively increased, plant will be harmed itself by destruction of cell and signal system and phenomenon of lipid peroxidation. In order to identify content of lipid peroxidation and activity of some enzymes scavenging ROS, phenotypical and physiological analysis was performed with two mutant lines, Till-II-877 and Till-II-894, comparing with cv. Dongan (WT). In phenotype analysis, two mutant lines give to well-conditioned growth better than WT in since 5 days after salt treatment. In enzyme activities, there was a modest difference in the content of catalase (CAT) and peroxidase (POD) between Till-II-877 and Till-II-894, two mutant lines showed high levels in CAT contents than WT. However, they express low levels in POD contents. In MDA analysis, the content of Till-II-877 was higher than that of WT, but Till-II-894 was lower. This result indicates that two mutants have different mechanism against salt stress.

구매종속성을 고려한 근사적 연속검토 재고모형 (Approximate Continuous Review Inventory Models with the Consideration of Purchase Dependence)

  • 박창규;서준용
    • 산업경영시스템학회지
    • /
    • 제38권4호
    • /
    • pp.98-108
    • /
    • 2015
  • This paper introduces the existence of purchase dependence that was identified during the analysis of inventory operations practice at a sales agency of dealing with spare parts for ship engines and generators. Purchase dependence is an important factor in designing an inventory replenishment policy. However, it has remained mostly unaddressed. Purchase dependence is different from demand dependence. Purchase dependence deals with the purchase behavior of customers, whereas demand dependence deals with the relationship between item-demands. In order to deal with purchase dependence in inventory operations practice, this paper proposes (Q, r) models with the consideration of purchase dependence. Through a computer simulation experiment, this paper compares performance of the proposed (Q, r) models to that of a (Q, r) model ignoring purchase dependence. The simulation experiment is conducted for two cases : a case of using a lost sale cost and a case of using a service level. For a case of using a lost sale cost, this paper calculates an order quantity, Q and a reorder point, r using the iterative procedure. However, for a case of using a service level, it is not an easy task to find Q and r. The complexity stems from the interactions among inventory replenishment policies for items. Thus, this paper considers the genetic algorithm (GA) as an optimization method. The simulation results demonstrates that the proposed (Q, r) models incur less inventory operations cost (satisfies better service levels) than a (Q, r) model ignoring purchase dependence. As a result, the simulation results supports that it is important to consider purchase dependence in the inventory operations practice.

Generation of a recombinant rabies virus expressing green fluorescent protein for a virus neutralization antibody assay

  • Yang, Dong-Kun;Kim, Ha-Hyun;Park, Yu-Ri;Yoo, Jae Young;Park, Yeseul;Park, Jungwon;Hyun, Bang-Hun
    • Journal of Veterinary Science
    • /
    • 제22권4호
    • /
    • pp.56.1-56.10
    • /
    • 2021
  • Background: Fluorescent antibody virus neutralization (FAVN) test is a standard assay for quantifying rabies virus-neutralizing antibody (VNA) in serum. However, a safer rabies virus (RABV) should be used in the FAVN assay. There is a need for a new method that is economical and time-saving by eliminating the immunostaining step. Objectives: We aimed to improve the traditional FAVN method by rescuing and characterizing a new recombinant RABV expressing green fluorescent protein (GFP). Methods: A new recombinant RABV expressing GFP designated as ERAGS-GFP was rescued using a reverse genetic system. Immuno-fluorescence assay, peroxidase-linked assay, electron microscopy and reverse transcription polymerase chain reaction were performed to confirm the recombinant ERAGS-GFP virus as a RABV expressing the GFP gene. The safety of ERAGS-GFP was evaluated in 4-week-old mice. The rabies VNA titers were measured and compared with conventional FAVN and FAVN-GFP tests using VERO cells. Results: The virus propagated in VERO cells was confirmed as RABV expressing GFP. The ERAGS-GFP showed the highest titer (108.0 TCID50/mL) in VERO cells at 5 days post-inoculation, and GFP expression persisted until passage 30. The body weight of 4-week-old mice inoculated intracranially with ERAGS-GFP continued to increase and the survival rate was 100%. In 62 dog sera, the FAVN-GFP result was significantly correlated with that of conventional FAVN (r = 0.95). Conclusions: We constructed ERAGS-GFP, which could replace the challenge virus standard-11 strain used in FAVN test.

A retroviral insertion in the tyrosinase (TYR) gene is associated with the recessive white plumage color in the Yeonsan Ogye chicken

  • Cho, Eunjin;Kim, Minjun;Manjula, Prabuddha;Cho, Sung Hyun;Seo, Dongwon;Lee, Seung-Sook;Lee, Jun Heon
    • Journal of Animal Science and Technology
    • /
    • 제63권4호
    • /
    • pp.751-758
    • /
    • 2021
  • The recessive white (locus c) phenotype observed in chickens is associated with three alleles (recessive white c, albino ca, and red-eyed white cre) and causative mutations in the tyrosinase (TYR) gene. The recessive white mutation (c) inhibits the transcription of TYR exon 5 due to a retroviral sequence insertion in intron 4. In this study, we genotyped and sequenced the insertion in TYR intron 4 to identify the mutation causing the unusual white plumage of Yeonsan Ogye chickens, which normally have black plumage. The white chickens had a homozygous recessive white genotype that matched the sequence of the recessive white type, and the inserted sequence exhibited 98% identity with the avian leukosis virus ev-1 sequence. In comparison, brindle and normal chickens had the homozygous color genotype, and their sequences were the same as the wild-type sequence, indicating that this phenotype is derived from other mutation(s). In conclusion, white chickens have a recessive white mutation allele. Since the size of the sample used in this study was limited, further research through securing additional samples to perform validation studies is necessary. Therefore, after validation studies, a selection system for conserving the phenotypic characteristics and genetic diversity of the population could be established if additional studies to elucidate specific phenotype-related genes in Yeonsan Ogye are performed.

Simulation of Sustainable Co-evolving Predator-Prey System Controlled by Neural Network

  • Lee, Taewoo;Kim, Sookyun;Shim, Yoonsik
    • 한국컴퓨터정보학회논문지
    • /
    • 제26권9호
    • /
    • pp.27-35
    • /
    • 2021
  • 인공생명체 연구는 자연 생명과 관련된 시스템이나 그 과정들, 진화 등을 평가해 다양한 응용과학 분야에 활용된다. 이러한 인공생명체의 원활한 활동을 위해 물리적 신체 설계와 행동 제어전략을 진화시키는 연구가 활발히 진행되었다. 그러나 형태와 신경망을 공진화시키는 것은 어렵기에 최적화된 움직임을 가진 인공생명체는 한 가지 형태에 한 가지 움직임만을 가지며 주변 환경 상황은 고려하지 않는 것이 대부분이다. 본 논문에서는 포식자-피식자 모델을 이용하여 형태와 신경망을 공진화하는 인공생명체가 환경적응형 움직임을 갖게 한다. 그런 다음 포식자-피식자 계층 구조를 최상위 포식자-중간 포식자-최하위 피식자 3단계로 확장하여 초기 개체군 밀도에 따라 시뮬레이션의 안정성을 판별하며 형태 진화와 개체군 역학 간의 상관관계를 분석한다.

Topical application of cervix with hyaluronan improves fertility in goats inseminated with frozen-thawed semen

  • Leethongdee, Sukanya;Thuangsanthia, Anone;Khalid, Muhammad
    • Animal Bioscience
    • /
    • 제34권6호
    • /
    • pp.985-992
    • /
    • 2021
  • Objective: Artificial insemination plays an important role in genetic improvement in the goat farming system. The aim of this study was to investigate the effect of cervical application of hyaluronan (HA) on the fertility in goats after cervical artificial insemination using frozen-thawed (F-T) semen. Methods: After oestrous synchronisation with progesterone sponges and pregnant mare serum gonadotropin injection, both nulli- and multi-parous goats, were randomly allocated to 2 groups, and were inseminated with 0.25 mL of F-T semen (150×106 spermatozoa) twice at 52 h and 56 h after sponge removal. Prior to the insemination, goats in Group 1 only were given topical cervical HA application at 48 h after sponge removal. Site of insemination was recorded as os-cervix or intra-cervix or intra-uterus. Pregnancy was tested ultrasonographically 42 days after insemination. The data on pregnancy rates and percentage of animals according to the site of semen deposition were compared by Chi-square analysis. Results: The overall pregnancy rate was significantly (p<0.004) higher in goats with prior application to the cervix with HA (63.3%) than without (36.0%). Same pattern was observed in the pregnancy rates of nulli- and multi-parous goats in both the groups. Percentage of nulliparous goats according to the site of insemination in the HA group did not differ between first and the second insemination. However, in multiparous goats the percentage of animals inseminated intra-cervically was significantly increased (p≤0.05) between the first and the second inseminations. Conclusion: The results suggest that significantly higher fertility rate in the "HA goats" compared to the "without HA" group was because of deeper insemination facilitated by topical cervical application of HA. The deeper insemination into the cervical canal increase the rate of fertilisation when the cervical artificial insemination is performed.

Application of simple and massive purification system of dsRNA in vivo for acute toxicity to Daphnia magna

  • CHOI, Wonkyun;LIM, Hye Song;KIM, Jin;RYU, Sung-Min;LEE, Jung Ro
    • Entomological Research
    • /
    • 제48권6호
    • /
    • pp.533-539
    • /
    • 2018
  • The RNA interference (RNAi) has been considered as an important genetic tool and applied to develop a new living modified (LM) crop trait which is an improvement of nutrient quality or pest management. The RNAi of DvSnf7 has been used for resistance to LM maize and the Western Corn Rootworm which is a major agricultural pest for the US Corn Belt. Most of the environmental risk assessments (ERA) of double strand RNA (dsRNA) have been performed using in vitro transcript products, and not in vivo expressed product. A large amount of dsRNA was required for the acute toxicity assay of water fleas. Therefore development of massive dsRNA purification techniques is critical. Daphnia, a freshwater microcrustacean, is a model organism for studying cellular and molecular mechanism involved in life history traits and ecotoxicology. In this study, we established the massive dsRNA purification method using Escherichia coli and implemented acute toxicity assays to Daphnia magna. As a result, the present RNase A and DNase I, dsRNA was efficiently purified without any special techniques or equipment. Even though purified dsRNA existed during the acute toxicity test, lethality or abnormal behavior were not observed in D. magna. These results indicated that GFP and DvSnf7 dsRNA were not significantly affected to D. magna due to their lack of sequence matching in its genome. The purification method of dsRNA and the acute toxicity assay of water fleas using purified dsRNA would be suitable for the toxicological studies of LMOs to aquatic non-target organisms.

사람 치주염 병소의 치은 연하 치태에서 분리된 Veillonella atypica KHUD-V1의 유전체 염기서열 해독 (Genome sequence of Veillonella atypica KHUD-V1 isolated from a human subgingival dental plaque of periodontitis lesion)

  • 이재형;신승윤;이한;양석빈;장은영;류재인;이진용;문지회
    • 미생물학회지
    • /
    • 제55권1호
    • /
    • pp.77-79
    • /
    • 2019
  • 본 논문에서는 한국인 만성 치주염 환자의 치은연하치태에서 분리된 Veillonella atypica KHUD-V1의 유전체 서열을 보고한다. 다른 V. atypica 균주와 달리, KHUD-V1에서는 프로 파지 및 이와 관련된 것으로 추정되는 여러 병독성 인자가 확인되었다. V. atypica KHUD-V1 균주 및 이 균주의 유전체 서열정보는 Veillonella의 유전체 다양성을 진화론적 관점에서 이해하고, V. atypica의 병독성 및 유전적 다양성에 기여하는 프로파지의 역할을 연구하는데 유용할 것이다.