• 제목/요약/키워드: experimental population

검색결과 887건 처리시간 0.031초

생선묵의 보장성에 관한 세균학적 연구 (Microbiological studies on the preservation of fish-paste products)

  • 안철우
    • 미생물학회지
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    • 제9권2호
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    • pp.47-54
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    • 1971
  • This study is concerned to the microbial population and its effects in the fish paste products. Experimental results were summarized as following orders ; 1) The number of bacteria in accordance with raw materials and coocking site waas known to as ; Wheat flor - $7.0{\times}10^8$/gram , Brayed fish meat - $2.0{\times}10^7$/gram, Cooking table - $6.1{\times}10^6$/$1.54cm^2$Chopped fish meat -$4.1{\times}10^6$/gram, Wooden plate - $5.5{\times}10^5$/218.32cm, Sodium chloride - $8.8{\times}10^4$/gram, Wheat starch - $4.5{\times}10^4$/gram, Fish meat - $2.3{\times}10^4$/gram. However, there were a few bacterial numbers less than 300 per gram of raw materials, such as monosodium glutamate, tap water, sugar, saccharine and eggs. 2) Bacterial population in the raw materials might be changed according to the conditions of preservation. 3) When the heat tratment is used for the preservation, the thermal effects were rarely found at the interior part of fish paste products. Conduction of heat into the interior part dose not rise about $84^{\circ}C$ and the survival of bacteria could be possible under the condition. Therefore, cooking being used requires further studies. 4) Number of bacteria in the fish paste products sold in the market was higher on April and May than those on June. Especially on June, the number of bacteriz in the interior part were found higher than those in the exterior part of the products.

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A Dual-Population Memetic Algorithm for Minimizing Total Cost of Multi-Mode Resource-Constrained Project Scheduling

  • Chen, Zhi-Jie;Chyu, Chiuh-Cheng
    • Industrial Engineering and Management Systems
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    • 제9권2호
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    • pp.70-79
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    • 2010
  • Makespan and cost minimization are two important factors in project investment. This paper considers a multi-mode resource-constrained project scheduling problem with the objective of minimizing costs, subject to a deadline constraint. A number of studies have focused on minimizing makespan or resource availability cost with a specified deadline. This problem assumes a fixed cost for the availability of each renewable resource per period, and the project cost to be minimized is the sum of the variable cost associated with the execution mode of each activity. The presented memetic algorithm (MA) consists of three features: (1) a truncated branch and bound heuristic that serves as effective preprocessing in forming the initial population; (2) a strategy that maintains two populations, which respectively store deadline-feasible and infeasible solutions, enabling the MA to explore quality solutions in a broader resource-feasible space; (3) a repair-and-improvement local search scheme that refines each offspring and updates the two populations. The MA is tested via ProGen generated instances with problem sizes of 18, 20, and 30. The experimental results indicate that the MA performs exceptionally well in both effectiveness and efficiency using the optimal solutions or the current best solutions for the comparison standard.

적응진화 알고리즘을 사용한 DC 모터 퍼지 제어기 설계에 관한 연구 (Design of a Fuzzy Logic Controller Using an Adaptive Evolutionary Algorithm for DC Series Motors)

  • 김동완;황기현;이재현
    • 한국정보통신학회논문지
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    • 제11권5호
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    • pp.1019-1028
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    • 2007
  • 본 논문에서는 적응진화알고리즘을 사용한 퍼지 제어기의 설계방법을 제안하였다. 적응진화알고리즘은 전역탐색특성이 우수한 유전알고리즘과 다음세대를 포함하는 해집단에 대해 적응적으로 우수한 국부탐색특성을 가진 진화전략을 사용한다. 재교배 과정에서 유전알고리즘과 진화전략을 위한 해집단의 분배는 적합도에 따라서 적응적으로 결정된다. 적응진화알고리즘은 퍼지제어기의 설계 파라메터인 퍼지변수에 대한 소속함수와 스케일 요소를 결정하는데 사용된다. 제기된 퍼지제어기의 성능을 평가하기 위해서 비선형 특성을 가진 실제 DC 모터 속도제어 시스템을 구성하여 실험하였으며, 실험결과 PD제어기의 경우보다 우수한 속도 제어성능을 가짐을 확인하였다.

Effects of feed intake on the diversity and population density of homoacetogens in the large intestine of pigs

  • Matsui, Hiroki;Mimura, Ayumi;Maekawa, Sakiko;Ban-Tokuda, Tomomi
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권12호
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    • pp.1907-1913
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    • 2019
  • Objective: Homoacetogens play important roles in the production of acetate in the large intestine of monogastric mammals. However, their diversity in the porcine large intestine is still unknown. Marker gene analysis was performed to assess the effects of energy level on the diversity and population densities of homoacetogens in porcine feces. Methods: Crossbred pigs were fed high or low energy-level diets. The high-intake (HI) diet was sufficient to allow a daily gain of 1.2 kg. The low-intake (LI) diet provided 0.6 times the amount of energy as the HI diet. Genetic diversity was analyzed using formyltetrahydrofolate synthetase gene (FHS) clone libraries derived from fecal DNA samples. FHS DNA copy numbers were quantified using real-time polymerase chain reaction. Results: A wide variety of FHS sequences was recovered from animals in both treatments. No differences in FHS clone libraries between the HI and LI groups were found. During the experimental period, no significant differences in the proportion of FHS copy numbers were observed between the two treatment groups. Conclusion: This is the first reported molecular diversity analysis using specific homoacetogen marker genes from the large intestines of pigs. There was no observable effect of feed intake on acetogen diversity.

우리나라 가족계획사업(家族計劃事業)의 현황소고(現況小考) ('Recent Progress of Family Planning in Korea')

  • 전병훈
    • Clinical and Experimental Reproductive Medicine
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    • 제7권1_2호
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    • pp.35-38
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    • 1980
  • Korean family planning program has been adopted as a part of the Economic Development Plan with strong national government backup. After initiation of family planning program, the increase rate of total population declined from 2.6 percent during 1955-1960, to 2.1 percent in 1960-1975, and 1.6 percent in 1979. Of course, we do not ascribe this population increase rate decline to the national family planning program alone. Other contributing factors have been changes such as growing numbers of induced absortions, a rising marriage age and economic development. Currently, 2,600 family planning workers are assigned in all myun of the country. 21 percent of the works are registered nurse, 9 percent are midwife and aid nurses occupy 70 percent (Table 1). Authorized clinics are 2,329 which composed 1,765 IUD clinics, 1,070 vasectomy clinics and 1,150 Fimale sterilization clinics (Table 2). Cumulative contraceptive services provided by government program, 1962-1974 is illustrated in Table 3. After government program in family planning has been initiated (1962-1978), estimated number of births averted by each methods was measured (Table 4). From 1962 to 1978, tendency of contraceptive acceptors is illustrated in Table 5 showed that IUD, oral pill and condom program is decreasing and in other hand, sterilization program is increasing very much. Attitude change toward family size (1965-1978), contraceptive practice and son preference are showed in Table 7, 8, respectively. Auther concluded that future program in family planning should target to the point, that smaller family size norm for maternal health should be emphasized rather than smaller size family for national development.

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Negative Effects of Inbreeding of Artificially Bottlenecked Drosophila melanogaster Populations

  • Kim, Baek-Jun
    • Proceedings of the National Institute of Ecology of the Republic of Korea
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    • 제2권2호
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    • pp.108-113
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    • 2021
  • Detrimental effects of inbreeding have been studied by many researchers for a long time. However, only a few studies have shown the occurrence of inbreeding depression due to evolutionary changes as a purging process. In this study, two different populations (inbreeding and outbreeding) of Drosophila melanogaster were compared to assess inbreeding effects on artificial population bottlenecks. For inbreeding conditions, a couple of D. melanogaster (one virgin and one male) were selected from an inbred population and cultured in a vial. For outbreeding conditions, a couple of D. melanogaster were selected from different populations and cultured in a vial. There were significant differences in body lengths of adults, but not in other parameters such as the total number of adults, the rate of survival, and the rate of wing mutants. The mean body length of adults of outbreeding populations was longer than that of inbreeding populations in the first generation (G1; P = 0.004), but not in the second generation (G2; P = 0.066). Although the other three parameters (total number of adults, rate of survival, and rate of wing mutants) showed differences in their mean values between inbreeding and outbreeding populations, these differences were not statistically significant. This might be due to genetic purging. This study demonstrated one additional experimental case related to inbreeding depression in artificial bottlenecked populations. Further studies are necessary to confirm the clear interaction between inbreeding depression and genetic purging using more generations and replicates (or samples) of D. melanogaster.

A many-objective evolutionary algorithm based on integrated strategy for skin cancer detection

  • Lan, Yang;Xie, Lijie;Cai, Xingjuan;Wang, Lifang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권1호
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    • pp.80-96
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    • 2022
  • Nowadays, artificial intelligence promotes the rapid development of skin cancer detection technology, and the federated skin cancer detection model (FSDM) and dual generative adversarial network model (DGANM) solves the fragmentation and privacy of data to a certain extent. To overcome the problem that the many-objective evolutionary algorithm (MaOEA) cannot guarantee the convergence and diversity of the population when solving the above models, a many-objective evolutionary algorithm based on integrated strategy (MaOEA-IS) is proposed. First, the idea of federated learning is introduced into population mutation, the new parents are generated through sub-populations employs different mating selection operators. Then, the distance between each solution to the ideal point (SID) and the Achievement Scalarizing Function (ASF) value of each solution are considered comprehensively for environment selection, meanwhile, the elimination mechanism is used to carry out the select offspring operation. Eventually, the FSDM and DGANM are solved through MaOEA-IS. The experimental results show that the MaOEA-IS has better convergence and diversity, and it has superior performance in solving the FSDM and DGANM. The proposed MaOEA-IS provides more reasonable solutions scheme for many scholars of skin cancer detection and promotes the progress of intelligent medicine.

핵비등열전달에 미치는 전열면표면조건의 영향 ('The Effect of Heating Surface Conditions on the Nucleate Boiling Heat Transfer')

  • 차지영;임장순;서정윤
    • 대한설비공학회지:설비저널
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    • 제5권3호
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    • pp.169-177
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    • 1976
  • The importance of surface conditions of nucleate boiling is well recognized and it has been known that the heat transfer to boiling liquid is closely related to the bubble population density. The bubble population density should depend on various factors such as heat flux, surface roughness, surface contamination, properties of liquid, etc. In this paper the effect of surface conditions on heat transfer in nucleate boiling is treated. The experiments were carried out with distilled water boiler, on the horizontal heating surfaces, sintered with various bronze particle, under atmospheric pressure. In addition, experimental investigation for the polished bronze surface was performed. By studing a coefficient Xb defined by eq. (9), which represents the bubble foaming ability of heating surface, generalized fomula on the heat transfer in the nucleate toiling were expressed. The coefficient $X_b$, determined empirically, is not constant and indicates a major influence of the sintered metal surfaces on the $\Delta$, necessary to sustain nucleate boiling at any given heat flux. In this study, the main results are obtained as follows; (1) At low temperature difference, the coefficient $X_b$ of sintered metal surface was found to he higher than the polished surface throughout the full range of experiments. (2) The optimum sintered structure showing the maximum coefficient $X_b$ has been confirmed to exist and it is encountered when particle diameter is $256{\mu}$.

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Monthly variations in semen parameters in a Sri Lankan population undergoing fertility evaluation

  • Anura Dissanayake
    • Clinical and Experimental Reproductive Medicine
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    • 제51권2호
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    • pp.120-124
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    • 2024
  • Objective: Seasonal variations in semen quality are known to occur in temperate regions, but results regarding tropical areas remain inconclusive. The aim of this study was to determine whether monthly variations in semen parameters are present among men in a tropical region. Methods: Data were retrospectively collected from semen analyses of 3,000 men over a 10-year period, from 2012 to 2022. Analysis of variance and the independent-samples t-test were employed to observe variations in semen parameters throughout the entire period and between months, respectively. Results: The mean±standard deviation sperm concentration was significantly lower in June, at 42.5±31.4 million/mL, compared to other months. The highest sperm concentration was found in March, at 57.8±42.6 million/mL, constituting a mean difference of 15.3 million/mL between the lowest and highest concentrations. The total sperm count displayed a similar pattern of monthly variation, with a difference of 47.2 million between the highest and lowest months. No significant monthly differences were observed in other parameters, such as sperm motility, morphology, and semen volume. Conclusion: Significant monthly variations in sperm concentration and total sperm count were evident in this Sri Lankan population. March, which displayed the highest sperm counts, is in the spring in temperate regions, while the month with the lowest counts, July, is part of the summer. Fluctuations in photoperiod appear to most strongly influence these variations.

Effects of Single Nucleotide Polymorphism Marker Density on Haplotype Block Partition

  • Kim, Sun Ah;Yoo, Yun Joo
    • Genomics & Informatics
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    • 제14권4호
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    • pp.196-204
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    • 2016
  • Many researchers have found that one of the most important characteristics of the structure of linkage disequilibrium is that the human genome can be divided into non-overlapping block partitions in which only a small number of haplotypes are observed. The location and distribution of haplotype blocks can be seen as a population property influenced by population genetic events such as selection, mutation, recombination and population structure. In this study, we investigate the effects of the density of markers relative to the full set of all polymorphisms in the region on the results of haplotype partitioning for five popular haplotype block partition methods: three methods in Haploview (confidence interval, four gamete test, and solid spine), MIG++ implemented in PLINK 1.9 and S-MIG++. We used several experimental datasets obtained by sampling subsets of single nucleotide polymorphism (SNP) markers of chromosome 22 region in the 1000 Genomes Project data and also the HapMap phase 3 data to compare the results of haplotype block partitions by five methods. With decreasing sampling ratio down to 20% of the original SNP markers, the total number of haplotype blocks decreases and the length of haplotype blocks increases for all algorithms. When we examined the marker-independence of the haplotype block locations constructed from the datasets of different density, the results using below 50% of the entire SNP markers were very different from the results using the entire SNP markers. We conclude that the haplotype block construction results should be used and interpreted carefully depending on the selection of markers and the purpose of the study.