• ALGAE
• /
• 제31권2호
• /
• pp.167-174
• /
• 2016

Biological response of cells to variable conditions should affect the expression level of certain genes. Quantification of these changes in target genes needs stable internal controls. Real-time quantitative polymerase chain reaction (PCR) has traditionally used reference or ‘housekeeping’ genes, that are considered to maintain equal expression in different conditions, to evaluate changes in target genes between samples and experimental conditions. Recent studies showed that some housekeeping genes may vary considerably in certain biological samples. This has not been evaluated in red algae. In order to identify the optimal internal controls for real-time PCR, we studied the expression of eleven commonly used housekeeping genes; elongation factor 1-alpha, glyceraldehyde-3-phosphate dehydrogenase, β-actin, polyubiquitin, 30S ribosomal gene, 60S ribosomal gene, beta-tubulin, alpha-tubulin, translation initiation factor, ubiquitin-conjugating enzyme, and isocitrate dehydrogenase in different life-history stages of Bostrychia moritziana. Our results suggest that glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and 30S ribosomal gene, have the most stable gene expression levels between the different life history stages (male, female, carposporophyte, and tetrasporophyte), while the other genes are not satisfactory as internal controls. These results suggest that the combinations of GAPDH and 30S would be useful as internal controls to assess expression level changes in genes that may control different physiological processes in this organism or that may change in different life history stages. These results may also be useful in other red algal systems.

• 디지털융복합연구
• /
• 제17권9호
• /
• pp.127-133
• /
• 2019

임의상환가능 상품은 옵션을 이용하여 수요창출과 리스크를 줄이는 서비스 파생상품의 일종이다. 본 논문은 임의상환가능 상품이 도입된 후, 예약 요청의 온라인승인 방법과 일괄승인 방법 둘의 성능을 비교한다. 최적의 예약관리법을 계산하기 위하여, 역행 동적계획법(Backward Dynamic Programming)과 확률적 최적화(Stochastic Optimization) 방법을 이용한다. 직관적으로는 공급자는 수요정보를 이용하여 일괄승인 방법으로 더 높은 수익을 올릴 것으로 예상되지만, 본 논문은 두 예약 요청 승인 방법의 예약관리전략과 수익은 동일하다는 것을 증명함으로써, 현행 예약 요청 승인 방법의 변화 없이 임의상환가능 상품을 빠르게 도입할 수 있다는 실무적인 기여도가 있다. 본 논문은 세 종류의 서비스 요금 클래스가 있을 경우 최적의 해를 정확히 구하였다. 향후 연구는 다양한 요금 모델에서 최적의 해를 구하는 것이다.

• Genomics & Informatics
• /
• 제15권4호
• /
• pp.123-127
• /
• 2017

Synonymous sites are generally considered to be functionally neutral. However, there are recent contradictory findings suggesting that synonymous alleles might have functional roles in various molecular aspects. For instance, a recent study demonstrated that synonymous single nucleotide polymorphisms have a similar effect size as nonsynonymous single nucleotide polymorphisms in human disease association studies. Researchers have recognized synonymous codon usage bias (SCUB) in the genomes of almost all species and have investigated whether SCUB is due to random nucleotide compositional bias or to natural selection of any functional exposure generated by synonymous mutations. One of the most prominent observations on the non-neutrality of synonymous codons is the correlation between SCUB and levels of gene expression, such that highly expressed genes tend to have a higher preference toward so-called optimal codons than lowly expressed genes. In relation, it is known that amounts of cognate tRNAs that bind to optimal codons are significantly higher than the amounts of cognate tRNAs that bind to non-optimal codons in genomes. In the present paper, we review various functions that synonymous codons might have other than regulating expression levels.

• 대한기계학회논문집B
• /
• 제27권8호
• /
• pp.1042-1050
• /
• 2003

A heating flow discharged from a 4-way ceiling type indoor unit has been investigated to determine the design parameters for the optimal flow control. The flow was measured by a PIV(particle image velocimetry) system and an experimental model of 1/10 scale with a transparent room was devised by satisfying the Archimedes number. This similarity is generally used in cases where the forced convection has similar magnitude of the natural convection. To optimize the heating flow, several vane angles and vane control algorithms of cross and right angle controls were considered. Regarding the vane angle, experimental results show that 30$^{\circ}$is an optimal angle to avoid re-suction flows without significant increase in flow noise. Temperature distribution measured in the environmental chamber ensures the increased thermal comfort when compared to the case, 60$^{\circ}$angle. At the optimal angle, applying open/close control gives rise to more uniform distribution of the heating flow than without control. Especially, the cross-control seems to be satisfactory for thermal comfort.

• 한국경영과학회:학술대회논문집
• /
• 한국경영과학회 2008년도 추계학술대회 및 정기총회
• /
• pp.267-284
• /
• 2008

Consider a supply chain where products are produced at a manufacturing system, shipped to a distribution center, and then supplied to customers. The distribution center controls inventory based on a base-stock policy, and whenever a unit of product is demanded by a customer, an order is released to the production system. Unsatisfied demand is backordered, and the inventory and backordered units are a function of the base-stock level. The manufacturing system is modeled as an M/M/s/c queueing system, and orders exceeding the limited buffer capacity are blocked and lost. The throughput of the manufacturing system and the steady state distribution of the outstanding orders are functions of number of servers and buffers of the manufacturing system. There is a profit obtained from throughput and costs due to servers and buffers of the manufacturing system, and also costs due to inventory positions of the distribution center, and we want to maximize the total production profit minus the total cost of the supply chain by simultaneously determining the optimal number of servers and buffers of the manufacturing system and the optimal base-stock level of the distribution center. We develope two algorithms, one analytical but without guarantee of the optimal solution and one optimal but without complete analytical proofs. The problem integrates strategic problem of the manufacturing system with tactical problem of the distribution center in a supply chain.

• 산업경영시스템학회지
• /
• 제4권4호
• /
• pp.63-69
• /
• 1981

As enterprises are getting bigger and bigger and more competecious, an engineering economy for the maximization of profit based on basic theory must be considered. This thesis present dynamic computer model for the decision which controls complicated and various man- machine system optimally. This model occur in general stage can be adaptable to every kind of enterprises. So, any one who has no expert knowledge is able to get the optimal solution. And decision tree used in this paper can be applied in every kinds of academic circles as well as whole the industrial world. This paper studied optimal management of engineering project based upon basic theory of engineering economy. It introduces and functionizes the variables which generalize every possible elements, set up a model in order to find out the variable which maximize the calculated value among many other variables. And the selected values ate used as decision- marking variables for the optimal management of engineering projects. It found out some problem of this model. They are : 1. In some kinds of man-machine system it refers to Probability, but other case, it depends on only experimental probability. 2. Unless decision making process (decision tree) goes on, this model can not be applied. So these cases, this paper says, can be solved by adapting finite decision tree which is analyzed by using the same technic as those in product introduction problem. And this paper set up the computer model in order to control every procedure quickly and optimally, using Fortran IV.

• 대한교통학회지
• /
• 제20권5호
• /
• pp.193-206
• /
• 2002

신호교차로로 구성된 네트워크의 시스템최적 신호시간산정을 위해 Cell Transmission 이론을 교통류 모형으로 활용한 신호최적화 모형을 제안한다. Cell Transmission 모형은 기존에 소개된 신호최적화 모형과는 달리 충격파, 대기행렬의 길이, 그리고 하류부 교차로 대기행렬의 역류(Spillback)과 같은 과포화 현상을 표현하는데 적절한 이론적이고 실제적인 배경을 지원한다. 모형에서 기점을 출발한 수요차량은 종점에 도착할 때까지 경로선택을 통해서, 그리고 신호시스템은 이러한 수요의 움직임 고려하여 신호시간요소의 최적화를 통한 네트워크의 비용을 최소화하기 위해 서로 협력한다는 의미에서 제안된 모형은 시스템 최적화를 의미한다. 모형은 혼합정수계획법으로 정식화되며 최적신호전략과 고정신호전략간의 실험계획을 통해 구축된 모형을 비교·평가한다.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2023년도 학술발표회
• /
• pp.25-25
• /
• 2023

The ensemble optimal interpolation (EnOI) scheme is a sub-optimal alternative to the ensemble Kalman filter (EnKF) with a reduced computational demand making it potentially more suitable for operational applications. Since only one model is integrated forward instead of an ensemble of model realizations, online estimation of the background error covariance matrix is not possible in the EnOI scheme. In this study, we investigate two Gaussian noise based ensemble generation strategies to produce dynamic covariance matrices for assimilation of water level observations into a distributed hydrological model. In the first approach, spatially correlated noise, sampled from a normal distribution with a fixed fractional error parameter (which controls its standard deviation), is added to the model forecast state vector to prepare the ensembles. In the second method, we use an adaptive error estimation technique based on the innovation diagnostics to estimate this error parameter within the assimilation framework. The results from a real and a set of synthetic experiments indicate that the EnOI scheme can provide better results when an optimal EnKF is not identified, but performs worse than the ensemble filter when the true error characteristics are known. Furthermore, while the adaptive approach is able to reduce the sensitivity to the fractional error parameter affecting the first (non-adaptive) approach, results are usually worse at ungauged locations with the former.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 추계학술대회
• /
• pp.893-898
• /
• 2004

The hydraulic cylinder is used for actuating a sluice gate which controls the volume of water in the reservoir. Generally, the one cylinder type is used to operate the sluice gate. In order to reduce the required cylinder force to operate the sluice gate significantly, the sequentially operated-hydraulic cylinders type is designed and the optimal locating points of cylinders are searched using the complex method that is one kind of constrained direct search method.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
• /
• pp.59-61
• /
• 2007

This paper proposes optimized actuator to obtain a improved position control ability and respiratory performance with reduced weight. Respiratory organ uses actuator and controls patient's respiratory air volume. Therefore, actuator decides respiratory performance. Redesign actuator using surface response method. Actuator that is reestablished through 3D-simulations searches whether have suitable characteristic to respiratory organ.