• 제목/요약/키워드: Set time

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Development of a Novel Long-Range 16S rRNA Universal Primer Set for Metagenomic Analysis of Gastrointestinal Microbiota in Newborn Infants

  • Ku, Hye-Jin;Lee, Ju-Hoon
    • Journal of Microbiology and Biotechnology
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    • 제24권6호
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    • pp.812-822
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    • 2014
  • Metagenomic analysis of the human intestinal microbiota has extended our understanding of the role of these bacteria in improving human intestinal health; however, a number of reports have shown that current total fecal DNA extraction methods and 16S rRNA universal primer sets could affect the species coverage and resolution of these analyses. Here, we improved the extraction method for total DNA from human fecal samples by optimization of the lysis buffer, boiling time (10 min), and bead-beating time (0 min). In addition, we developed a new long-range 16S rRNA universal PCR primer set targeting the V6 to V9 regions with a 580 bp DNA product length. This new 16S rRNA primer set was evaluated by comparison with two previously developed 16S rRNA universal primer sets and showed high species coverage and resolution. The optimized total fecal DNA extraction method and newly designed long-range 16S rRNA universal primer set will be useful for the highly accurate metagenomic analysis of adult and infant intestinal microbiota with minimization of any bias.

생산일정계획을 위한 지식 기반 모의실험 (Knowledge Based Simulation for Production Scheduling)

  • 나태영;김승권;김선욱
    • 대한산업공학회지
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    • 제23권1호
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    • pp.197-213
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    • 1997
  • It is not easy to find a good production schedule which can be used in practice. Therefore, production scheduling simulation with a simple dispatching rule or a set of dispatching rules is used. However, a simple dispatching rule may not create a robust schedule, for the same rule is blindly applied to all internal production processes. The presumption is that there might be a specific combination of appropriate rules that can improve the efficiency of a total production system for a certain type of orders. In order to acquire a better set of dispatching rules, simulation is used to examine the performance of various combinations of dispatching rule sets. There are innumerable combination of rule sets. Hence it takes too much computer simulation time to find a robust set of dispatching rule for a specific production system. Therefore, we propose a concept of the knowledge based simulation to circumvent the problem. The knowledge based simulation consists of knowledge bases, an inference engine and a simulator. The knowledge base is made of rule sets that is extracted from both simulation and human intuition obtained by the simulation studies. For a certain type of orders, the proposed system provides several sets of dispatching rules that are expected to generate better results. Then the scheduler tries to find the best by simulating all proposed set of rules with the simulator. The knowledge-based simulator armed with the acquired knowledge has produced improved solutions in terms of time and scheduling performance.

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춘천지역 도시열섬의 특성과 대기질에 미치는 영향 (Aspects of Urban Heat Island and Its's Effect on Air Pollution Concentration in Chunchon Area)

  • 이종범;김용국;김태우
    • 한국대기환경학회지
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    • 제9권4호
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    • pp.303-309
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    • 1993
  • An observational study of urban heat island was carried out using field data obatined during 6 days in May and August 1992 in Chunchon(population size 180.000). Air temperature was measured at 64 points along two sampling ruoutes by themisters attached to cars. Both routes cover urban and rural area and across the cneter of urban area. Continuous observation of air sonde was perfomed to clarify heights of nocturnal boundary layer(NBL) at the center of urban area. Surface meteorological observations were performed at both urban and rural sites. This study showed that heat island phenomena was obviously observed at the urbanized area during the night time with low wind speed. The average NBL heights exteded to about 10 meters, but varied with meteorological conditions. After sunset, the air temperature decreased with time at both sites and cooling rate at the urban site was greater than the rural site. The maximum heat island intensity was 7.5$^{\circ}$C at 21 LST, May 4. Usingthe two meteorological data sets obtained from urban and rural sites, the air pollutant concentration was calculated by Gaussian plume model which can obtain not only horizontal distribution of concentration but also vertical distribution. The result indicated that the concentration resulted from urban meteorological data set was lower than that from rural meteorological data set. It was also calculated that the air pollutant extended to higher level in urban meteorological data set than that in rural meteorological data set.

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QSO Selections Using Time Variability and Machine Learning

  • 김대원;;변용익
    • 천문학회보
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    • 제36권2호
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    • pp.64-64
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    • 2011
  • We present a new quasi-stellar object (QSO) selection algorithm using a Support Vector Machine, a supervised classification method, on a set of extracted time series features including period, amplitude, color, and autocorrelation value. We train a model that separates QSOs from variable stars, non-variable stars, and microlensing events using 58 known QSOs, 1629 variable stars, and 4288 non-variables in the MAssive Compact Halo Object (MACHO) database as a training set. To estimate the efficiency and the accuracy of the model, we perform a cross-validation test using the training set. The test shows that the model correctly identifies ~80% of known QSOs with a 25% false-positive rate. The majority of the false positives are Be stars. We applied the trained model to the MACHO Large Magellanic Cloud (LMC) data set, which consists of 40 million lightcurves, and found 1620 QSO candidates. During the selection, none of the 33,242 known MACHO variables were misclassified as QSO candidates. In order to estimate the true false-positive rate, we crossmatched the candidates with astronomical catalogs including the Spitzer Surveying the Agents of a Galaxy's Evolution (SAGE) LMC catalog and a few X-ray catalogs. The results further suggest that the majority of the candidates, more than 70%, are QSOs.

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토양의 염기치환 용량 측정에 관한 연구 (측정장치에 대하여) (Determination of Cation Exchange Capacity in Soils (study on the apparatus))

  • 최대웅;이종목
    • 한국토양비료학회지
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    • 제6권2호
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    • pp.83-88
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    • 1973
  • 염기치환용량 측정을 위하여 염기의 포화 과잉염기의 세척을 위한 작업단계에서 현재 사용되어 오던 원심분리기, 흡인여과장치 보다 새로이 고안된 Column set를 이용 하였을때 다음과 같은 양호한 결과를 얻었다. 1. CEC 측정치는 흡인여과시의 치와 99.91%인 고도의 상관이 있었으며 반복성의 변이가 흡인여과 1.94%에 비해 1/3이나 적은 0.66%로 정확도도 더욱 높았다. 2. Column set 이용시 흡인여과에 비하여 작업시간 및 노력이 1/3정도 절약되고 한거번에 다량의 시료를 처리할 수 있다. 3. 고가의 기계(Vacuum pump, Shaker, Section, Apparatus, Centrifuge) 등이 구비되지 않아도 CEC를 측정할 수 있었다.

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Proposing new models to predict pile set-up in cohesive soils

  • Sara Banaei Moghadam;Mohammadreza Khanmohammadi
    • Geomechanics and Engineering
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    • 제33권3호
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    • pp.231-242
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    • 2023
  • This paper represents a comparative study in which Gene Expression Programming (GEP), Group Method of Data Handling (GMDH), and multiple linear regressions (MLR) were utilized to derive new equations for the prediction of time-dependent bearing capacity of pile foundations driven in cohesive soil, technically called pile set-up. This term means that many piles which are installed in cohesive soil experience a noticeable increase in bearing capacity after a specific time. Results of researches indicate that side resistance encounters more increase than toe resistance. The main reason leading to pile setup in saturated soil has been found to be the dissipation of excess pore water pressure generated in the process of pile installation, while in unsaturated conditions aging is the major justification. In this study, a comprehensive dataset containing information about 169 test piles was obtained from literature reviews used to develop the models. to prepare the data for further developments using intelligent algorithms, Data mining techniques were performed as a fundamental stage of the study. To verify the models, the data were randomly divided into training and testing datasets. The most striking difference between this study and the previous researches is that the dataset used in this study includes different piles driven in soil with varied geotechnical characterization; therefore, the proposed equations are more generalizable. According to the evaluation criteria, GEP was found to be the most effective method to predict set-up among the other approaches developed earlier for the pertinent research.

HIERARCHICAL SWITCHING CONTROL OF LONGITUDINAL ACCELERATION WITH LARGE UNCERTAINTIES

  • Gao, F.;Li, K.Q.
    • International Journal of Automotive Technology
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    • 제8권3호
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    • pp.351-359
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    • 2007
  • In this study, a hierarchical switching control scheme based on robust control theory is proposed for tracking control of vehicle longitudinal acceleration in the presence of large uncertainties. A model set consisting of four multiplicative-uncertainty models is set up, and its corresponding controller set is designed by the LMI approach, which can ensures the robust performance of the closed loop system under arbitray switching. Based on the model set and the controller set, a switching index function by estimating the system gain of the uncertainties between the plant and the nominal model is designed to determine when and which controller should be switched into the closed loop. After theoretical analyses, experiments have also been carried out to validate the proposed control algorithm. The results show that the control system has good performance of robust stability and tracking ability in the presence of large uncertainties. The response time is smaller than 1.5s and the max tracking error is about $0.05\;m/S^2$ with the step input.

SET을 기반으로 한 전자상거래 트랜잭션 모델링에 대한 연구 (A Study on Electronic Commerce Transaction Modeling based on SET)

  • 고영철;송병열;조현규;함호상
    • 한국전자거래학회지
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    • 제2권1호
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    • pp.79-94
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    • 1997
  • Commerce activities which are free form space and time constraint using a communication network are called Electronic Commerce(EC). Because of sending a commercial information using open network such as Internet in EC, they need the security of commerce information (payment information and purchase information), checking the integrity of transferring data and certifying all parts participated in commerce for a secure commerce. Recently Visa and MasterCard Co. released the Secure Electronic Transaction (SET) Protocol for secure payment card transaction on Internet. This paper proposes a Secure Electronic Commerce Transaction Model(SECTM) using SET in order to support the secure commerce on Internet. The proposed transaction model prevents merchant from abusing the cardholder's payment information (credit-card number etc.) and enables cardholder to shop securely in Electronic Shopping Mall.

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어군탐지기에 의한 정치망내의 어군의 행동과 어군량 추정 (Schooling Behavior and Estimation of the Fish School in Set Net by Fish Finder)

  • 신형일
    • 수산해양기술연구
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    • 제22권1호
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    • pp.11-18
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    • 1986
  • Schooling behavier to a fishing gear and estimation of the volume of fish school in set net have ~ been studied by making use of such techniques as visual observations, underwater cameras, under- water televison. However, all of these observation techniques are subject to restrictions caused by illumination, underwater visibility, underwater transparent and sea conditions. For the above mentioned reasoa, one of the most effective method by this time become generally known a method using fish finder. In this paper, in order to control the fishing ground of set net effectively and to develope the telemetric fish finder, the experiments for the target strength, underwater shape of fishing gear, schooling behavier and volume of fish school with fish finder were performed at Galgott fishing ground of set net located Keouje Island, 15th-24th July and 18th-20th October in 1985. The results of these experiment showed that a method using fish finder in fishing grOlllld of set net is available for estimating distribution and school size, fish behavier in relation to a fishing gear and underwater shape of fishing gears.

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다중 해상도 레벨 세트 방식을 이용한 기하 활성 모델 (A Geometric Active Contour Model Using Multi Resolution Level Set Methods)

  • 김성곤;김두영
    • 한국정보처리학회논문지
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    • 제6권10호
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    • pp.2809-2815
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    • 1999
  • Level set, and active contour(snakes) models are extensively used for image segmentation or shape extraction in computer vision. Snakes utilize the energy minimization concepts, and level set is based on the curve evolution in order to extract contours from image data. In general, these two models have their own drawbacks. For instance, snake acts pooly unless it is placed close to the wanted shape boundary, and it has difficult problem when image has multiple objects to be extracted. But, level set method is free of initial curve position problem, and has ability to handle topology of multiple objects. Nevertheless, level set method requires much more calculation time compared to snake model. In this paper, we use good points of two described models and also apply multi resolution algorithm in order to speed up the process without decreasing the performance of the shape extraction.

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