• Title/Summary/Keyword: Competitive exclusion

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New Mutation Rule for Evolutionary Programming Motivated from the Competitive Exclusion Principle in Ecology

  • Shin, Jung-Hwan;Park, Doo-Hyun;Chien, Sung-I1
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.165.2-165
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    • 2001
  • A number of previous researches in evolutionary algorithm are based on the study of facets we observe in natural evolution. The individuals of species in natural evolution occupy their own niche that is a subdivision of the habitat. This means that two species with the similar requirements cannot live together in the same niche. This is known as the competitive exclusion principle, i.e., complete competitors cannot coexist. In this paper, a new evolutionary programming algorithm adopting this concept is presented. Similarly in the case of natural evolution , the algorithm Includes the concept of niche obtained by partitioning a search space and the competitive exclusion principle performed by migrating individuals. Cell partition and individual migration strategies are used to preserve search diversity as well as to speed up convergence of an ...

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Isolation, In vitro Antibacterial Activity, Bacterial Sensitivity and Plasmid Profile of Lactobacilli

  • Lonkar, P.;Harne, S.D.;Kalorey, D.R.;Kurkure, N.V.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.9
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    • pp.1336-1342
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    • 2005
  • The present research work was conducted to evaluate the beneficial effects as well as the safety aspects of lactobacilli as probiotic. Lactobacilli were isolated from poultry faecal samples, feed samples and from some known preparations procured from poultry feed manufacturers. L. acidophilus and L. sporogenes were tested for the antibacterial activity against four poultry pathogens viz. Escherichia coli, Salmonella spp., Proteus spp. and Pseudomonas aeruginosa. Cell free supernatant (CFS) of L. acidophilus exhibited significantly higher antibacterial activity against Salmonella spp. at original pH (4.50${\pm}$0.02). At the adjusted pH (6.50${\pm}$0.02) significantly higher antibacterial activity was recorded against indicator organism except for P. aeruginosa. Likewise, L. sporogenes exhibited similar antibacterial activity at original as well as adjusted pH except for E. coli. Antibacterial activity against E. coli was significantly higher at adjusted pH than at original pH of CFS. The competitive exclusion of E. coli by lactobacilli over the intestinal epithelial cells (IEC) was checked. L. acidophilus strain I, which was of poultry origin, exhibited maximum attachment over IEC as compared to other three strains of non-poultry origin viz. L. acidophilus strain II, L. sporogenes strain I and II. Overall, L. acidophilus exhibited higher competitive exclusion as compared to L. sporogenes. All the lactobacilli of poultry origin were most sensitive to penicillin G, amoxycillin, ampicillin and chloramphenicol, least sensitive to sulphamethizole, ciprofloxacin, neomycin, norfloxacin and pefloxacin and resistant to metronidazole and nalidixic acid. The isolates from probiotic preparations were most sensitive to ampicillin, amoxycillin and tetracycline, least sensitive to sulphamethizole, norfloxacin, neomycin and ceftriazone and resistant to nalidixic acid and metronidazole. Eight of the multiple drug resistant lactobacilli isolates were studied for the presence of plasmids. Plasmids could be extracted from six isolates of lactobacilli. These plasmids could be responsible for bacteriocin production or for antibiotic resistance of the strains. The lactobacilli need further studies regarding their safety for use in the probiotic preparations.

Location Strategy of Sports Oulets to Maximize the Market Share (시장 점유율을 최대로 할 수 있는 스포츠용품점 위치 결정 전략)

  • Lee, Sang-Un;Lee, Young-Sook;Choi, Seong-Beom;Han, Tae-Yong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.3
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    • pp.93-101
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    • 2013
  • This paper suggests optimal location algorithm of new firm $A(F_A)^{\prime}s$ p(p$B(F_B)$ already operating q outlets of sports in the market. This algorithm selects top q nodes among $V=V{\backslash}F_B$ nodes that covers maximum nodes based on the shortest distance. Then, q nodes choose next node that has a maximum cover with inclusion-exclusion principle. At the time of same number of cardinality in q sets to pre-defined q, we select the maximum cover node set. This algorithm called by competitive algorithm. The competitive algorithm simply decides the optimal location of the outlets p=1,2,3,4 for q=5. Also, we show that the market share of competitive algorithm can be maximize.

Competitive Algorithm of Set Cover Problem Using Inclusion-Exclusion Principle (포함-배제 원리를 적용한 집합피복 문제의 경쟁 알고리즘)

  • Sang-Un Lee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.4
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    • pp.165-170
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    • 2023
  • This paper proposes an algorithm that can obtain a solution with linear time for a set cover problem(SCP) in which there is no polynomial time algorithm as an NP-complete problem so far. Until now, only heuristic greed algorithms are known to select sets that can be covered to the maximum. On the other hand, the proposed algorithm is a competitive algorithm that applies an inclusion-exclusion principle rule to N nodes up to 2nd or 3rd in the maximum number of elements to obtain a set covering all k nodes, and selects the minimum cover set among them. The proposed algorithm compensated for the disadvantage that the greedy algorithm does not obtain the optimal solution. As a result of applying the proposed algorithm to various application cases, an optimal solution was obtained with a polynomial time of O(kn2).

Ecological Evolution by Competitive Exclusion / An Experimental Approach with Cellular Slime Mold , Polysphondylium pallidum (경쟁배타에 의한 생태적 진화: 세포성 점균 Polysphondylium pallidum에 대한 실험적 접근)

  • ;Robert M. Eisenberg
    • The Korean Journal of Ecology
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    • v.17 no.3
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    • pp.299-310
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    • 1994
  • Intraspecific clonal interactions have important influences on a population structure of the cellular slime mold (CSM). This study was to investigate whether or not evolutionary change in a population could be induced by clonal competition, and to elucidate how various clones in a population evolve in a homogeneous environment of laboratory culture. The characteristic clones of Polysphondylium pallidum which had different resource consumption rates (RCR) and mating types I and II were selected for study. Investigation was conducted for 4 experimental time interval $(T_0-T_4)$; one experimental time interval took almost 10-14 days from inoculation to havest of fruiting bodies. Two sets of 50 clones were cultured from 50 clones at To, and RCR variations of the population were compared between $(T_0\;and\;T_4)$ for each set of clones. Each clone of the CSM had a diverse resource consumption rate, or growth rate, in a homogeneous and limited Cerophyl agar plate despite the passage of 48-56 generations from the beginning of the experiment. Diverse clones with different growth rate could coexist in one site of the homogeneous agar plate as well as heterogeneous soil microenvironment. When there was high clonal diversity of RCR, a clone in a population had high chances to encounter other clones with resultant increased clonal competition. In one set, 26 of 37 clones of mating type I were changed to mating type Il for the 4 experimental time intervals, which indicated that the rate of competitive exclusion among clones during total experiment from $(T_0\;to\;T_4)$ was 0.703. In another set, 31 of 37 clones of mating type I were changed to mating type II , having the rate of competitive exclusion 0.838. The frequency of each of mat~ng types changed by 0.93-1.29% in each successive generation. The competitive exclusion among clones occurred by 1.26-1.75% when approximately $2.6{\times}10^8$ bacterial cells were provided as food and thereafter one generation of myxamoebae of CSM elapsed at room temperature. This finding implicated that in the vegetative state of P, pallidurn there was 1.26-1.75% probabil~ty of evolutionary change per generation changing from one clone to another clone.

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The Paradox of the Plankton (플랑크톤 패러독스)

  • Lee, Hak Young;Moon, Sung-Gi;Huh, Man-Kyu
    • Journal of Life Science
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    • v.25 no.5
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    • pp.601-606
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    • 2015
  • Hutchinson (1961) proposed that the large number of species in most plankton communities is remarkable in review of the competitive exclusion principle, which suggests that in homogeneous, well-mixed environments species that compete for the same resources cannot coexist. The principle of competitive exclusion would lead us to conclude that only a few species could coexist in such circumstances. Nevertheless, numerous competing species in most natural habitats are able to coexist, while generally only few resources (niches) limit these communities. It is coined “the paradox of plankton” by Hutchinson. We reviewed some literature of the proposed solutions and give a brief overview of the mechanisms proposed so far. The proposed mechanisms that we discuss mainly include spatial and temporal heterogeneity in physical and biological environment, externally imposed or self-generated spatial segregation, horizontal mesoscale turbulence of ocean characterized by coherent vortices, oscillation and chaos generated by several internal and external causes, stable coexistence and compensatory dynamic under fluctuating temperature in resource competition, and finally the role of toxin-producing phytoplankton in maintaining the coexistence and biodiversity of the overall plankton populations. Especially we sited Roy and Chattopadhyay’s reviews and their toxin-producing hypothesis by phytoplankton. This review may be some information to study plankton communities and effect to put the solutions to the paradox that have been proposed over the years into perspective.

A Strategy to Improve Service Quality Satisfaction in Super-Super-Market

  • Cho, Yong-Jun
    • Journal of the Korean Data and Information Science Society
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    • v.18 no.1
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    • pp.123-139
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    • 2007
  • Recently, Super-Super-Market(SSM) is facing more and more difficult situation due to the expansion of hypermarket and target marketing of specialized shop. In this situation, Customer Satisfaction Management(CSM) is emerging as a core business factor to make continuous growth without competitive exclusion. Especially, the first factor in CSM in distribution industry is a Service Quality Satisfaction. In this paper, with a selection of 3-markets as a sample for the research, I have tried to look for necessary Service Quality(SQ) factors in SSM and deduced Service Quality Index(SQI), loyalty and Index of detail factor in SQ through survey. Based on these results, strategic factors required to improve SQ was found and strategic directions for SQ were proposed through matrix portfolio analysis.

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A Study of the Development of Apartment's Structural Cost Saving Checklist through the Case Research (사례분석을 통한 공동주택 골조공사의 원가절감 체크리스트 개발에 관한 연구)

  • Lee, Kyeong-Seob;Suh, Sang-Wook
    • Korean Journal of Construction Engineering and Management
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    • v.11 no.6
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    • pp.65-77
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    • 2010
  • Our nation's housing construction is given much weight over 32% in 2007 and especially apartment is taking over 67%. If we put into construction environment consideration, we are having a trouble with price cap policy and the realestate recession due to the global economic crisis. So in order to get competitive power and supply of cheap apartment, the necessity of cost saving is increasing. This research collected the past constructed apartment project's cost saving examples which were influencing on the construction cost, quality and time. We analyzed collected cost saving datum and assorted these in compliance with classification system. By analysis of correlation among datum with exclusion and integration, we make a propose cost saving Checklist that will be a base data to give a chance to use in working level and other research.

Reduction of the Antigenicity of Whey Protein by Enzymatic Hydrolysis (효소가수분해에 의한 유청단백질의 항원성 저하)

  • Ha, Woel-Kyu;Juhn, Suk-Lak;Kim, Jung-Wan;Lee, Soo-Won;Lee, Jae-Young;Shon, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.26 no.1
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    • pp.74-80
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    • 1994
  • As a preliminary study about the reduction of the antigenicity of whey protein isolate(WPI) by treatment of chymotrypsin, trypsin, pancreatin, and protease from Aspergillus oryzae, the properties and antigenicities of whey protein hydrolysates(WPH) were investigated. When degrees of hydrolysis (DH) were measured by use of trinitrobenzensulfonic acid(TNBS), the DH of the WPH treated by pancreatin or protease from Aspergillus oryzae$(5.05{\sim}11.47)$ were much higher than those of the tryptic or chymotryptic WPH$(15.67{\sim}20.20)$. And the pretreatments of heat$(75^{\circ}C)$, 20 min and/or pepsin resulted in higher DH of WPH, generally. When the molecular distributions of the WPH were determined by high performance size exclusion chromatography(HPSEC), the ratios of polypeptides with molecular weight more than 10kDa ranged from 12% to 36%, and the average molecular weights and the average peptide lengths of the WPH were $4,252{\sim}9,132$ dalton and $38{\sim}83$ amino acids, respectively. And there was no bitter taste in all of the WPH. Results of SDS-PAGE showed that most of intact native proteins were eliminated by the enzymatic hydrolysis but there were a few bands of peptides larger than 14.2 kDa in some WPH. When antigenicity was assayed by competitive inhibition enzyme-linked immunosorbent assay(cELISA), monovalent antigenicity of WPH to rabbit anti-WPI antiserum were lowered to $10^{-1.7}-10^{-4.9}$ times and less by the enzymatic hydrolysis. And the pretreatments of heat and pepsin resulted in the lowest antigenicicy within a group of enzymatic hydrolysis, especially in case of the pancreatic hydrolysate(PDP) whose antigenicity was found almost to be removed.

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Comparison of Weed Populations in Conventional Till and No-till Experimental Agroecosystems (경운 및 무경운 실험 농업생태계에서의 잡초개체군의 비교)

  • Park, Tae Yoon;Eugene P. Odum
    • The Korean Journal of Ecology
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    • v.18 no.4
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    • pp.471-481
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    • 1995
  • The weed population dynamics as affected by contrasting conventional tillege (CT) and no-tillage (NT) practices with a minimum herbicide application was studied in Athens, Georgia, U.S.A. Common chickweed (Stellaria media) was the most common spring weed while johnsongrass (Sorghum halepense), sicklepod (Cassia obtusifolia), and pigweed (Amaranthus retroflexus) accounted for 89∼97% of net production during summers of 1983 and 1984. Total weed production in summer of 1984 was 2∼5 times greater than that of 1983. Weed production was greater in NT plots than in CT plots in summer of 1983, but reverse was the case in summer of 1984. In spring, net production in NT plots was greater than that in CT plots, especially, in 1985. Species diversity was consistently higher in NT plots, but in the wet summer of 1984 the pattern was different, with higher diversity in CT plots. Weed species diversity was higher in the spring rye crop than in the summer grain sorghum crop. The larger but less diverse weed populations in summer of 1984 indicated that these populations experienced competitive exclusion. Under the favorable summer moisture conditions the three dominant species grew so vigorously and quickly as to exclude many less common species that were able to survive under the drier conditions in 1983. The three dominant species not only excluded other weeds in 1984 but also greatly reduced crop production. The perennial johnsongrass was equally successful, or even more so, in CT plots as in NT plots. Plowing did not kill johnsongrass rhizomes but tended to break them up, thus increasing the number of individual plants that appear after the plowing. It means that johnsongrass was not controlled by the plowing. In summer of 1983, a moderate amount of weedy growth was maintained with a minimum amount of gerbicide application in NT and CT plots. It is possible that a small mixed weed population would be beneficial by providing cover for predatory and parasitic arthropods, and by reducing soil temperature and moisture losses.

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