• Journal of Animal Science and Technology
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• 제60권12호
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• pp.31.1-31.10
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• 2018

Background: Research on loci influencing milk production traits of dairy cattle is one of the main topics of investigation in livestock. Many genomic regions and polymorphisms associated with dairy production have been reported worldwide. In this context, the purpose of this study was to identify candidate loci associated with milk yield in Argentinean dairy cattle. A database of candidate genes and single nucleotide polymorphisms (SNPs) for milk production and composition was developed. Thirty-nine SNPs belonging to 22 candidate genes were genotyped on 1643 animals (Holstein and Holstein x Jersey). The genotypes obtained were subjected to association studies considering the whole population and discriminating the population by Holstein breed percentage. Phenotypic data consisted of milk production values recorded during the first lactation of 1156 Holstein and 462 Holstein ${\times}$ Jersey cows from 18 dairy farms located in the central dairy area of Argentina. From these records, 305-day cumulative milk production values were predicted. Results: Eight SNPs (rs43375517, rs29004488, rs132812135, rs137651874, rs109191047, rs135164815, rs43706485, and rs41255693), located on six Bos taurus autosomes (BTA4, BTA6, BTA19, BTA20, BTA22, and BTA26), showed suggestive associations with 305-day cumulative milk production (under Benjamini-Hochberg procedure with a false discovery rate of 0.1). Two of those SNPs (rs43375517 and rs135164815) were significantly associated with milk production (Bonferroni adjusted p-values < 0.05) when considering the Holstein population. Conclusions: The results obtained are consistent with previously reported associations in other Holstein populations. Furthermore, the SNPs found to influence bovine milk production in this study may be used as possible candidate SNPs for marker-assisted selection programs in Argentinean dairy cattle.

• 한국경영과학회지
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• 제24권3호
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• pp.39-47
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• 1999

It has been concluded that the performance of class-based storage policy is better than the performance of random storage policy in the literature. However, the rack shortage problem assigned to the 1st class items makes the decision hard to apply the class-based storage policy in practice. In this paper, a new common zone concept is introduced between two classes to resolve the problem with class-based storage policy. The common zone is the area to accept items from both classes. An AS/RS model is developed for computer simulation study and the effect of common area sizes with various AS/RS operation conditions is analyzed.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.253-256
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• 2000

In general, Automated Storage/Retrieval Systems (AS/RS ) have racks of equal sized cells to utilize the concept of unit-load. Most of the techniques for the performance estimation of a unit-load AS/RS are a static model or computer simulation. Especially, their models were developed under assumption that the Storage/Retrieval (S/R) machine performs only single command (SC) or dual command (DC). In reality, defending on the operating policy and the status of the system at a particular time, the S/B machine performs a SC or a DC, or becomes .: idle. In order to resolve these weak points, we propose a stochastic model for the performance estimation of unit-load AS/RS by using a single-server queueing model. Expected numbers of waiting storage and retrieval commands are found

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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• pp.956-957
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• 1995

대부분의 AS/RS 운영정책 연구는 등급별 저장이 임의저장보다 우수한 수행도를 나타낸다고 결론짓고 있다. 그러나 실제 현장에서는 임의 저장이나 이와 유사한 형태의 근거리 저장이 주로 사용되고 있는 실정이다. 이와 같이 AS/RS 운영에 관련된 연구결과들이 현실에서 적용되지 못하고 있는 데는 여러 가지 이유가 있겠지만 본 연구에서는 빈번하게 바뀌고 있는 생산계획에 그 원인을 두었다. 신제품의 투입으로 기존 제품의 생산량에 변화가 일어나는 경우가 빈번한 생산현장을 감안하여 GPSS로 AS/RS의 모형을 구축하고 그 운용상태를 파악해 볼 수 있도록 임의저장, 2등급저장, 3등급저장 등의 경우를 시험.분석하였다. 각 경우별로 적정 허용 변동율과 최대 허용 변동율, 변동에 대한 반응도 등이 분석되었다.

• 산업경영시스템학회지
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• 제27권3호
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• pp.26-30
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• 2004

We consider an AS/RS(Automated Storage/ Retrieval System) which performs both of single and dual commands. The service times of single and dual commands are assumed to be differently distributed. Steady-state probabilities at the service completion epochs are calculated. Then, we transform the arrival rates of storage and retrieval commands into those of single and dual commands. Using this, we propose a non-preemptive queueing model with priority for the performance analysis of an AS/RS, and obtain approximated means of queue lengths and waiting times.

• 산업공학
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• 제3권2호
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• pp.39-51
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• 1990

One of the most important and powerful tools available for design and/or study of the operation of complex systems and processes is simulation. Since automated material handling systems like AS/RS are often quite complex, a network-based simulation model is developed to analyze an automobile part supplier's automated storage and retrieval system(AS/RS). The network simulation model is implemented in the SLAM Ⅱ on a VAX 8800 computer. Performance of the AS/RS was tested for 3 dispatching rules, 3 work load levels, 2 storage policies, 3 levels of stacker crane break-down, and 2 conveyor system layouts. Results indicate that the AS/RS performance is primarily affected by the dispatching rule and work load level.

• 산업경영시스템학회지
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• 제21권46호
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• pp.137-146
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• 1998

Most studies related to AS/RS are about operation policies or system designs. However, the studies on operation policy could not deal with various products using the single unit load system. In this paper, two different sized units are introduced and six different AS/RS operation policies are developed to process the different sized items. Computer simulation is used to evaluate AS/RS performances on various operation policies and to find the most effective operation policy for each case. The simulation model is developed using GPSS/PC and operation policies include COL-FIFO-SP, SIL-FIFO-SP, COL-RN-SP, COL-FIFO-LP, SIL-FIFO-LP and COL-RN-LP. The policies are evaluated based on the criteria of crane utilization, rack utilization, crane moving time, throughput and waiting time.

• 산업공학
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• 제12권2호
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• pp.237-246
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• 1999

The Automated Storage/Retrieval System(AS/RS) is very expensive to be built. But there are few tools available which can be used to design the storage systems optimally considering overall system building costs and constraints. In this paper, we propose a design support system for optimal design of AS/RS which includes different sized cells using expert systems and mathematical models considering customer's demands. The optimization models are to be used to minimize the total cost including building, equipment and operation costs. Expert system technique is utilized for using the experiences of skilled designers. By using the proposed system, AS/RS can be designed accurately, economically and efficiently.

• 미생물학회지
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• 제47권1호
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• pp.14-21
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• 2011

리보플라빈 생성효소(riboflavin synthase)는 기질인 두 분자의 6,7-dimetyl-8-ribityllumazine과 결합 후, 4-탄소 단위(4-carbon unit)의 자리 옮김 반응을 거쳐 한 분자의 리보플라빈과 한 분자의 pyrimidine 유도체를 형성하는 반응을 촉매한다. 대장균(Escherichia coli) 리보플라빈 생성효소의 아미노-말단 도메인 절반(N-terminal domain half)과 카복시-말단 도메인 절반(C-terminal domain half)은 매우 유사한 내부 자체 아미노산 서열(intra-molecular amino acid sequence)을 갖는다. 아미노-말단 영역 리보플라빈 생성효소(N-RS) 단백질의 구조와 형광 특성을 알아보기 위하여 중합효소 연쇄 반응과 위치지정 돌연변이를 통하여 10개 이상의 돌연변이 아미노-말단 리보플라빈 생성효소 단백질을 코드 하는 유전자를 증폭시켜 pQE30 벡터에 삽입한 재조합 플라스미드를 제조하여, 과발현시킨 후 분리 정제하였다. 대부분의 아미노-말단 도메인 리보플라빈 생성효소의 돌연변이 단백질들은 야생형과 같이 형광성 리간드인 6,7-dimetyl-8-ribityllumazine 혹은 리보플라빈과 결합할 수 있는 능력을 지니고 있었으나, N-RS C47D, N-RS ET66,67DQ 돌연변이 단백질의 경우는 리간드와의 결합능력이 현저히 떨어져 형광을 띠지 않았다. 대부분의 돌연변이 단백질들의 형광 세기는 야생형 단백질(N-RS wt)보다 낮았으나, N-RS C48S는 예외적으로 야생형 단백질에 비해 2배 이상의 형광세기를 가졌다. 이와 같은 결과를 바탕으로 리보플라빈 생성효소와 형광성 리간드 사이의 상호작용을 예측 할 수 있으며, N-RS C48S 돌연변이 단백질의 형광성을 활용하여 효과적으로 효소 저해제를 발굴할 수 있는 고속다중 스크리닝 법(high-throughput screening system)으로써 활용될 수 있을 것이다.

• Journal of the Korean Wood Science and Technology
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• 제41권1호
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• pp.1-11
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• 2013

본 연구에서는 은수원사시나무의 산 당화공정에서 생성되는 고형 부산물의 화학적, 구조적 특성을 관찰하였다. 산 가수분해는 황산과 염산을 사용하였고, 1차 가수분해농도를 72%, 36%, 18%로 변화를 주었고, 2차 가수분해에서 4%로 동일하게 희석하였다. 가수분해 후 액상 가수분해액과 고형 부산물을 각각 분리하였고 고형 부산물을 각각 RS72, RS36, RS18, RC36, RC18이라고 하였다. 황산의 농도가 높아짐에 따라 생성된 고형부산물은 감소(71.2~21.4%)하였지만, 염산의 농도는 고형 부산물의 생성량(65.0~67.0%)에 큰 영향을 주지 않았다. 또한 RS36과 RS18은 고형 부산물 질량 대비 23.6%, RC36과 RC18은 각각 25.6%, 27.3%가 리그닌으로 이루어져 있었다. 고형 부산물의 열분해산물 분석 결과 Levoglucosan, Furfural 등 탄수화물 유래 물질과 리그닌 유래 물질인 Guaiacol, Syringol 등이 검출되었지만 RS72에서는 리그닌 유래 물질만이 검출되었다. 또한 열중량분석결과 고형 부산물 내 리그닌 함량이 높아질수록 다량의 탄이 생성되고 최대 중량 감소율이 감소하여 염산에 비해 황산이, 또한 산의 농도가 높을수록 화학적으로 축합된 구조를 형성하는 것을 확인하였다.