• Title/Summary/Keyword: Enumeration method

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An Enumeration Algorithm for the Rolling Stock Requirement Plan (철도차량소요계획을 위한 열거알고리듬)

  • Kim Seongho;Kim Dong-Hee;Choi Tae-Sung
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.514-521
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    • 2004
  • A routing is the path that an actual train set follows as it moves from one train to another train in a timetable. The number of routings is equivalent to the number of trainsets required to cover the timetable. The primary factors of rolling stock requirement plan include evaluating the minimum number of routings. This can be formulated as a set partitioning problem and solved using enumeration method or column generation method. In this paper we presents an enumeration algorithm which is useful to implement the enumeration method for the rolling stock requirement plan.

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An Enumeration Algorithm for Generating the Candidate Routings in a Set Partitioning Problem Approach to the Rolling Stock Requirement Plan (철도차량소요계획에 대한 집합분할문제 접근에서 후보운용생성을 위한 열거알고리즘)

  • 김성호;김동희;최태성
    • Journal of the Korean Society for Railway
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    • v.7 no.4
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    • pp.326-331
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    • 2004
  • A routing is the path that an actual trainset follows as it moves from one train to another train in a timetable. The number of routings is equivalent to the number of trainsets required to cover the timetable. The primary factors of rolling stock requirement plan include evaluating the minimum number of routings. This can be formulated as a set partitioning problem and solved using enumeration method or column generation method. In this paper we presents an enumeration algorithm which is useful to implement the enumeration method for the rolling stock requirement plan.

Structural Classification and Enumeration of Pin-Jointed Kinematic Chains (핀 조인트로 구성된 기구학적 연쇄들의 구조적 분류 및 열거)

  • 이종기;신재균
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.3
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    • pp.565-572
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    • 1994
  • A method for the classification of kinematic chains according to the similarity in their structures is proposed. Classifcation code is defined from the contracted graph of the kinematic chain. This method of classifying kinematic chains can be effectively used for the systematic enumeration of structurally distinct kinematic chains given the number of links and degrees of freedom of the kinematic chains. Two separate steps for the enumeration are developed in the study. The first step is to generated all the possible classification codes and the next step is to generate individual kinematic chains belonging to each classification code generated. Using this two step procedure, kinematic chains up to 12 links are successfully enumerated in the present study. It is concluded that the two step method can be efficiently used for the type synthesis of mechanisms.

Source Enumeration Method using Eigenvalue Gap Ratio and Performance Comparison in Rayleigh Fading (Eigenvalue Gap의 Ratio를 이용한 신호 개수 추정 방법 및 Rayleigh Fading 환경에서의 신호 개수 추정 성능 비교)

  • Kim, Taeyoung;Lee, Yunseong;Park, Chanhong;Choi, Yeongyoon;Kim, Kiseon;Lee, Dongkeun;Lee, Myung-Sik;Kang, Hyunjin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.5
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    • pp.492-502
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    • 2021
  • In electronic warfare, source enumeration and direction-of-arrival estimation are important. The source enumeration method based on eigenvalues of covariance matrix from received is one of the most used methods. However, there are some drawbacks such as accuracy less than 100 % at high SNR, poor performance at low SNR and reduction of maximum number of estimating sources. We suggested new method based on eigenvalues gaps, which is named AREG(Accumulated Ratio of Eigenvalues Gaps). Meanwhile, FGML(Fast Gridless Maximum Likelihood) which reconstructs the covariance matrix was suggested by Wu et al., and it improves performance of the existing source enumeration methods without modification of algorithms. In this paper, first, we combine AREG with FGML to improve the performance. Second, we compare the performance of source enumeration and direction-of-arrival estimation methods in Rayleigh fading. Third, we suggest new method named REG(Ratio of Eigenvalues Gaps) to reduce performance degradation in Rayleigh Fading environment of AREG.

Stydies on the Selective Screening Method of Bifidobacteria Used in Yoghurt (호상 요구르트 제품에 이용되는 Bifidobacteria 의 선택적 검출 방법)

  • 박희경;허태련
    • Microbiology and Biotechnology Letters
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    • v.23 no.2
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    • pp.214-219
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    • 1995
  • In fermentation of dairy products, bifidobacteria is used in conjunction with other lactic acid bacteria, such as L. acidophilus, L. bulgaricus and S. thermophilus, rendering the enumeration of bifidobacteria difficult. In order to develop optimum conditions for selective enumeration of bifidobacteria, we examined MIC of several antibiotics against various bifidobacteria and other lactic acid bacteria. The growth of L. acidophilus, L. bulgaricus and S. thermophilus were inhibited by lithium chloride at the concentration of less than 4 mg/ml, whereas growth inhibition of bifidobacteria occurred at concentrations over 6-10 mg/ml. Tetracycline and chloramphenicol were also found to selectively inhibit growth of other lactic acid bacteria at the concentration of 1-3 $\mu$g/ml. Addition of 6 mg/ml lithium chloride, 1 $\mu$g/ml, tetracycline or 3 $\mu$g/ml chloramphenicol to medium was found to be optimal for selective enumeration of bifidobacteria. By using these three inhibitory chemicals in the TPY medium, higher number of bifidobacteria were selectively isolated than with NPNL agar and LP agar.

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Phase Offset Enumeration Method with Error Detection and Its Application to Synchronization of PN Sequences

  • Song Young-Joan
    • Journal of electromagnetic engineering and science
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    • v.5 no.1
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    • pp.26-30
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    • 2005
  • It is important to know phase offsets of PN(Pseudo Noise) sequences in spread spectrum communications since the acquisition is equivalent to making a phase offset between a receiving PN sequence and a PN sequence of local PN generator be identical. In this paper, a phase offset enumeration method for PN sequences with error detection, and its application to the synchronization are proposed. The phase offset enumeration for an n-tuple PN sequence and its error detection are performed when one period of the sequence is received. Once the phase offset of the receiving sequence is calculated, we can easily accomplish the synchronization by initializing shift registers of a local PN generator according to the phase offset value. The mean acquisition time performance of the proposed scheme was derived analytically. Since this synchronization scheme can be realized by using simple circuit and acquires very rapid acquisition in high SNR but shows performance degradation in low SNR, it can be especially useful in indoor and office environments.

Service Identification of Internet-Connected Devices Based on Common Platform Enumeration

  • Na, Sarang;Kim, Taeeun;Kim, Hwankuk
    • Journal of Information Processing Systems
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    • v.14 no.3
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    • pp.740-750
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    • 2018
  • There are a great number of Internet-connected devices and their information can be acquired through an Internet-wide scanning tool. By associating device information with publicly known security vulnerabilities, security experts are able to determine whether a particular device is vulnerable. Currently, the identification of the device information and its related vulnerabilities is manually carried out. It is necessary to automate the process to identify a huge number of Internet-connected devices in order to analyze more than one hundred thousand security vulnerabilities. In this paper, we propose a method of automatically generating device information in the Common Platform Enumeration (CPE) format from banner text to discover potentially weak devices having the Common Vulnerabilities Exposures (CVE) vulnerability. We demonstrated that our proposed method can distinguish as much adequate CPE information as possible in the service banner.

A Microbiological Study on the Frozen Beef and Pork in Seoul Area (서울시 일부지역 冷凍牛肉 및 豚肉의 細菌學的 調査硏究)

  • Shin, Kyoung-Ho;Lee, Yong-Wook
    • Journal of Environmental Health Sciences
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    • v.13 no.2
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    • pp.65-74
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    • 1987
  • This study was carried out to investigate the bacterial contamination of retailed beef and pork in Seoul area. For this study 44 samples were collected at butcheries and department stores from March to April, 1987 and were examined on the following items. 1. Comparison of bacterial contamination between butcheries and department stores. 2. Degree of bacterial enumeration by repair method of injured microorganisms in the frozen beef and pork. 3. Degree of bacterial contamination in the frozen beef and pork. As the result of this study, the following conclusions were obtained. 1. Difference of bacterial contamination between butcheries and department stores was not significant. 2. Enumeration of total bacterial count by solid repair procedure resulted in about 1.5-fold increase in beef and about 1.8-fold increase in port. 3. Enumeration of total coliform count by liquid repair procedure resulted in about 32.1-fold increase in beef and about 12.0-fold in pork. 4. Salmonella species were not detected, but Staphylococcus species were detected 8 cases (18.2%) in beef, 7 cases (15.9%) in pork. 5. In total bacterial count, all beef samples were lower than 10$^6$/g, but 2 pork samples were higher than 10$^6$/g. 6. The ratio of total coliform count to total bacterial count was 0.07 in beef, 0.05 in pork by standard method and 0.48 in beef, 0.25 in pork by repair method.

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식품내의 미생물 분리를 위한 dryfilm 방법의 평가연구

  • 하상도
    • Microbiology and Biotechnology Letters
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    • v.24 no.2
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    • pp.178-184
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    • 1996
  • Dryfilm method by using 3M Petrifilm$^{TM}$ has been examined to replace conventional agar method for isolation of microorganisms from foods. The objectives of the present study were to evaluate suitability of dryfilm method as a microbial isolation method and to determine the effect of antimicrobial agent on dryfilm for isolation of microorganisms from foods. Five different foods, milk, ground beef, fishery surimi, Takju and wheat flour were used to isolate the natural microflora in foods and the inoculated Escheri chia coli. Standard method agar (SMA, Difco) and Petrifilm$^{TM}$ aerobic count (PAC, 3M) were used to isolate total microorganisms from foods. Violet red bile agar (VRBA), brilliant green lactose bile (BGLB) broth and Petrifilm$^{TM}$ coliform count (PCC, 3M) were used to isolate coliforms from foods. E. coli broth (EC broth) and Petrifilm$^{TM}$ E. coli count (PEC, 3M) were used to isolate E. coli from foods. Acidified potato dextrose agar (APDA) and Petrifilm$^{TM}$ yeast & mold count (PYMC, 3M) were used to isolate yeasts and molds from foods. Total aerobic plate counts isolated from five different foods by SMA and PAC (3M) were riot significantly different each other at P<0.05 level and were highly correlated each other ($\geq$0.96). Mugwort extract as an antimicrobial agent did not affect microbial enumeratiion of Dryfilm. Significantly higher number of coliform colonies were formed on VRBA than PCC (3M) from ground beef, but they were not significantly different in coliform colonies from milk samples. PCC (3M) and BGLB were not significantly different for enumeration of coliforms in milk and beef samples. Significantly higher number of E. coli were isolated by EC broth than PEC from ground beef, but these were not significontly different for enumeration of E. coli from milk. Yeast and mold counts isolated from Takju and wheat flour by APDA and PYMC (3M) were not significantly different at P<0.05 level. These data indicate that dryfilm method by using 3M Petrifilm$^{TM}$ can be successively used as an alternative to conventional agar method for enumeration of microorganisms in various foods.

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Investigation on the modified continual reassessment method in phase I clinical trial (1상 임상실험에서 수정된 CRM에 대한 연구)

  • 강승호
    • The Korean Journal of Applied Statistics
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    • v.15 no.2
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    • pp.323-336
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    • 2002
  • In this paper we consider the modified continual reassessment method in which a cohort consists of three patients. Simulation has been a main research tool in the investigation of CRM. In this paper we propose complete enumeration as an alternative of simulation. Using new method we show that the expected toxicity rate at the MTD converges to the target toxicity rate well as the sample size increases.