• 제목/요약/키워드: population problem

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국내 종계장에 있어서 미생물 오염에 관한 연구 (Studies on Bacterial Contamination of Domestic Chicken Breeding Farm)

  • 김기석;이희수;김상희;박근식
    • 한국가금학회지
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    • 제18권3호
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    • pp.151-159
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    • 1991
  • 최근 국내 종계장에서 문제시되고 있는 종계의 산란저하 원인조사의 일환으로 정상농장 1개소와 산란저하의 문제를 경험하고 있는 농장 2개소를 임의선정하고 하계절과 동계절에 각각 1회씩 1개 농장별로 재선정한 각각 3개 계사씩을 대상으로 하여 각 계사내 공기, 급여사료, 음수 및 인공수정기의 세균 오염도를 조사하였다. 계사내 공기중의 세균 오염도는 매우 높았으나(일반세균: 농장별 평균 543~815개/직경 9cm 평판배지, 대양균군: 5~12.4개, 포도상구균종: 273~393개)산란저하의 문제농장과 정상농장간에 유의한 차이는 인정되지 않았다. 그러나 문제농장에 있어서 계사간에 산란저하나 대양균 감염으로 인한 수난관염이나 복막염 등 질병발생의 문제계사에서의 공기중 오염도는 다른 정상계사에서 보다도 높았다. 급여사요에 있어서는 급여 전부터 정상농장에서 보다도 문제농장에서의 세균오염도가 높았으며, 정상농장에서는 급여전후 과정에서 세균 오염도의 변화가 없었으나 문제농장에서는 급여전에 비해 급여중인 사료에서의 오염도가 훨씬 증가하는 경향이었다. 급수원의 음수는 정상농장과 문제농장간에 차이 없이 세균 오염도가 극히 낮아 대장균군 및 일반세균 모두가 일반수질의 위생판정 기준에 적합하였다. 급수중인 음수는 정상농장에서는 급수원과 큰 차이가 없었으나 문제농장에서는 대장균군이 검출되었으며 일반세균 오염도의 급격한 증가현상을 나타내었다. 산란감소나 복막염 및 수난관염의 발생문제가 있는 농장에서의 인공수정구의 세균 오염도가 다른 농장에서 보다 훨씬 높았으나 위생적인 조치후에는 각 농장 공히 상호 비슷한 수준으로 매우 감소하였다.분간의 유전상관 및 표현형상관은 난백중과 난자중간에 각각 0.089~0.654, 0.984~0.235 이었고, 난백중과 난각중간에는 각각 0.396~0.925, 0.225~0.544이었으며, 난황중과 난각중간에는 각각 0.227~0.375, 0.098~0.358이었다.CP의 PER은 시판되는 SCP의 것과 별다른 차이를 보이지 않았다. 그리나 후반기에 있어서는 Fermentation을 끝내고 3일과 6일 후에 냉동 건조시킨 SCP의 PER이 시판되는 SCP의 것보다 약간 저조함을 보였다. 그리고 Casein의 PER은 총 사육기간은 통하여 별 변동이 없음에 반하여 후반기에 SCP의 PER이 급격한 저하를 보임은 SCP 사용상의 문제점을 나타낸 것으로 해석 된다.자체에 대한 인터넷 이용자들의 반응은 매우 너그러운 것으로 나타났다.與群)에서는 뇨량(尿量)이 계속(繼續) 감소(減少)하였다$(0.88{\pm}0.10{\rightarrow}0.59{\pm}0.09{\rightarrow}0.45{\pm}0.09\;ml/1.5\;hr)$. 이상(以上)의 결과(結果)는 ethanol의 혈중농도(血中濃度)가 높을수록 더 심(甚)한 혈압강하작용(血壓降下作用)을 나타내며, ethanol 로 인(因)한 이뇨작용(利尿作用)도 ethanol 량(量)이 증가(增加)함에 따라 뇨량(尿量)도 증가(增加)함을 보여 주었다.ults showed that the overall quality of Sullungtang significantly decreased as the parity increased for Hanwoo cows.

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Ratio and Product Type Exponential Estimators of Population Mean in Double Sampling for Stratification

  • Tailor, Rajesh;Chouhan, Sunil;Kim, Jong-Min
    • Communications for Statistical Applications and Methods
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    • 제21권1호
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    • pp.1-9
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    • 2014
  • This paper discusses the problem of estimation of finite population mean in double sampling for stratification. In fact, ratio and product type exponential estimators of population mean are proposed in double sampling for stratification. The biases and mean squared errors of proposed estimators are obtained upto the first degree of approximation. The proposed estimators have been compared with usual unbiased estimator, ratio and product estimators in double sampling for stratification. To judge the performance of the proposed estimators an empirical study has been carried out.

Generalized Ratio-Cum-Product Type Estimator of Finite Population Mean in Double Sampling for Stratification

  • Tailor, Rajesh;Lone, Hilal A.;Pandey, Rajiv
    • Communications for Statistical Applications and Methods
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    • 제22권3호
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    • pp.255-264
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    • 2015
  • This paper addressed the problem of estimation of finite population mean in double sampling for stratification. This paper proposed a generalized ratio-cum-product type estimator of population mean. The bias and mean square error of the proposed estimator has been obtained upto the first degree of approximation. A particular member of the proposed generalized estimator was identified and studied from a comparison point of view. It is observed that the identified particular estimator is more efficient than usual unbiased estimator and Ige and Tripathi (1987) estimators. An empirical study was conducted in support of the theoretical findings.

Multivariate Rotation Design for Population Mean in Sampling on Successive Occasions

  • Priyanka, Kumari;Mittal, Richa;Kim, Jong-Min
    • Communications for Statistical Applications and Methods
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    • 제22권5호
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    • pp.445-462
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    • 2015
  • This article deals with the problem of estimation of the population mean in presence of multi-auxiliary information in two occasion rotation sampling. A multivariate exponential ratio type estimator has been proposed to estimate population mean at current (second) occasion using information on p-additional auxiliary variates which are positively correlated to study variates. The theoretical properties of the proposed estimator are investigated along with the discussion of optimum replacement strategies. The worthiness of proposed estimator has been justified by comparing it to well-known recent estimators that exist in the literature of rotation sampling. Theoretical results are justified through empirical investigations and a detailed study has been done by taking different choices of the correlation coefficients. A simulation study has been conducted to show the practicability of the proposed estimator.

On the Bayes risk of a sequential design for estimating a mean difference

  • Sangbeak Ye;Kamel Rekab
    • Communications for Statistical Applications and Methods
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    • 제31권4호
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    • pp.427-440
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    • 2024
  • The problem addressed is that of sequentially estimating the difference between the means of two populations with respect to the squared error loss, where each population distribution is a member of the one-parameter exponential family. A Bayesian approach is adopted in which the population means are estimated by the posterior means at each stage of the sampling process and the prior distributions are not specified but have twice continuously differentiable density functions. The main result determines an asymptotic second-order lower bound, as t → ∞, for the Bayes risk of a sequential procedure that takes M observations from the first population and t - M from the second population, where M is determined according to a sequential design, and t denotes the total number of observations sampled from both populations.

인구구조 변화(저출산·고령화)에서 외국인력 도입을 위한 이주노동자의 법제도적 개선방안 연구 (A Study on the Improvement Approaches of Immigration Workers' Legal System to Introduce Foreign Workers according to change the Population Structure (Low Fertility and Aging))

  • 이척희;노재철
    • 산업진흥연구
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    • 제6권1호
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    • pp.79-86
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    • 2021
  • 인구구조의 변화로 저출산·고령화 문제는 심각한 생산가능 인구감소로 이어져 외국인력 도입의 필요성이 증대되고 있다. 본 연구는 인구구조 변화가 본격적으로 시작되는 저출산고령화 시대에 생산가능 인구를 확충하기 위해서는 외국인력의 도입이 가장 유효하다고 보며, 이를 위해 이주노동자 도입에 대한 법제도적인 개선방안을 마련하고자 하였다. 연구 결과, 첫째, 이주노동자 법제도의 통일과 정비가 이루어져야 한다. 「출입국관리법」과 「노동법」이 협조관계를 구축할 수 있도록 관리기관의 신설이나 일원화가 필요하다. 둘째, 「출입국관리법」을 개정하여 이주노동자들이 취업할 수 있는 길이 용이해져야 한다. 고용허가제와 국적취득에 대한 긍정적 검토가 필요하다. 셋째, 이주노동자에 대한 형평성 및 차별이 없어야 한다. 상호호혜의 원칙하에서 사용자와 이주노동자가 평등하게 차별 받지 않도록 해야 한다. 넷째, 이주노동자의 법제도에서 사회보험제도를 추가하여야 한다. 따라서 4대 사회보험을 비롯한 각종 보험제도에서 이주노동자들이 차별 받지 않도록 법제도의 정비가 이루어져야 한다. 결론적으로 인구구조의 변화로 저출산·고령화 문제는 심각한 사회문제화되어 있으며, 이로 인한 생산가능인구의 감소는 우려할 만한 수준에 도달해 있다. 이주노동자의 취업 및 근무 환경의 중요성은 높아지고 있다. 그럼에도 불구하고 관련 법제도적 문제점은 상존해 있으며, 이주노동자에 대한 법제도적 개선방안이 필요하다.

단순진화 알고리듬을 위한 애플리케이션 프레임워크 개발 (Development of an Application Framework for Simple Evolutionary Algorithms)

  • 이수연;정호연;서광언;김여근
    • 산업공학
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    • 제12권4호
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    • pp.540-550
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    • 1999
  • In evolutionary algorithm, there exist various models for the evolution of the population with respect to schemes and strategies for reproduction. In the application of the algorithm to a specific problem, one model suitable to the problem is to be properly chosen and a program expert or a software is needed to help implement and test a designed algorithm. In this study, the software for simple evolutionary algorithms(SEA) with one population is developed. The software is designed as an application framework type, so that it may be friendly, allow users to add some program, and operate under the environment of Windows. For this, hierarchical classes for components of SEA are first designed by means of an object-oriented approach and then a library for SEA is built by them. With the library, developed is an application framework that can generate a frame code for an application program. The software proposed here can be used as a generalized tool for solving problems in a wide range of domains.

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진화 알고리듬을 위한 객체지향 모델링과 클래스 라이브러리 구현 (Object-Oriented Modeling and Implementation of a Class Library for Evolutionary Algorithms)

  • 정호연;이수연;곽재승;김용주;박기태;현철주
    • 경영과학
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    • 제17권2호
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    • pp.75-86
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    • 2000
  • In evolutionary algorithm, there exist various models for the evolution of the population with respect to schemes and strategies for reproduction. In the application of the algorithm to a specific problem, one model suitable to the problem is to be properly chosen and a program expert or a software is needed to help implement and test a designed algorithm. In this study, abject oriented modeling and the class library for simple evolutionary algorithms(SEA) with one population is developed. The library proposed here can be used as a generalized tool for solving problems in a wide range of domains.

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유전알고리즘에 기반한 Job Shop 일정계획 기법 (A Genetic Algorithm-based Scheduling Method for Job Shop Scheduling Problem)

  • 박병주;최형림;김현수
    • 경영과학
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    • 제20권1호
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    • pp.51-64
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    • 2003
  • The JSSP (Job Shop Scheduling Problem) Is one of the most general and difficult of all traditional scheduling problems. The goal of this research is to develop an efficient scheduling method based on genetic algorithm to address JSSP. we design scheduling method based on SGA (Single Genetic Algorithm) and PGA (Parallel Genetic Algorithm). In the scheduling method, the representation, which encodes the job number, is made to be always feasible, initial population is generated through integrating representation and G&T algorithm, the new genetic operators and selection method are designed to better transmit the temporal relationships in the chromosome, and island model PGA are proposed. The scheduling method based on genetic algorithm are tested on five standard benchmark JSSPs. The results were compared with other proposed approaches. Compared to traditional genetic algorithm, the proposed approach yields significant improvement at a solution. The superior results indicate the successful Incorporation of generating method of initial population into the genetic operators.

A Novel Algebraic Framework for Analyzing Finite Population DS/SS Slotted ALOHA Wireless Network Systems with Delay Capture

  • Kyeong, Mun-Geon
    • ETRI Journal
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    • 제18권3호
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    • pp.127-145
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    • 1996
  • A new analytic framework based on a linear algebra approach is proposed for examining the performance of a direct sequence spread spectrum (DS/SS) slotted ALOHA wireless communication network systems with delay capture. The discrete-time Markov chain model has been introduced to account for the effect of randomized time of arrival (TOA) at the central receiver and determine the evolution of the finite population network performance in a single-hop environment. The proposed linear algebra approach applied to the given Markov problem requires only computing the eigenvector ${\prod}$ of the state transition matrix and then normalizing it to have the sum of its entries equal to 1. MATLAB computation results show that systems employing discrete TOA randomization and delay capture significantly improves throughput-delay performance and the employed analysis approach is quite easily and staightforwardly applicable to the current analysis problem.

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