• Title/Summary/Keyword: Niche

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Simultaneous Enrichment of Novel Filamentous-Like Bacterial Population in Lab-Scale Granular Anaerobic Ammonia Oxidation (Anammox) Sequencing Batch Reactor (실험실 규모 입상 혐기성 암모늄 산화 연속회분식 반응조 내의 신종 사상균 동시 농화 배양에 관한 연구)

  • Park, Hongkeun
    • Journal of Korean Society on Water Environment
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    • v.29 no.3
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    • pp.377-382
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    • 2013
  • Enriching anammox bacteria (AMX) in a lab-scale granular sequencing batch reactor using local digester centrate, we observed the significant enrichment of the filamentous-like bacterial population. These bacteria were revealed as novel bacterial species (termed CHL) belonging to Chlorobi/Bacteroidetes phyla via Denaturing Gradient Gel Electrophoresis (DGGE). Further, niche differentiation of AMX and CHL quantification was observed in granule and filament biomass, suggesting AMX was dominant in the granule and CHL was dominant in the filament. Therefore, it was confirmed the structural role of CHL was indeed to aid the granule formation of the AMX. In parallel, the physiological role of CHL was suspected to degrade biopolymers in the digester centrate using nitrate as an electron acceptor.

Analysis of the Structure of Technology Spillover on Industries by Analyzing Patents (특허분석을 이용한 기술-산업간 기술지식의 파급구조 분석 -무인기 기술을 중심으로-)

  • Jung, Ha-Gyo;Whang, Kyu-Seung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.10 no.1
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    • pp.86-93
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    • 2007
  • The objective of this paper is to examine the structure of technology spillover from UAV(unmanned air vehicle) technology to other industries by applying patents analysis. The network analysis on patent data of USPTO(United Stated Patents and Trademark Office) from 1981 to 2000 was adopted to investigate the characteristic change of the technology spillover The results show that the influence of the UAV technology to other industries has grown over the twenty years period. For the weapon system development, this study provides a research basis to estimate the technology spillover effects on industries. Searching a structural niche from the inter-industrial knowledge flow structure might be a useful technique to find core technologies which generate large technology spillover on the other industries.

Process Optimization Formulated in GDP/MINLP Using Hybrid Genetic Algorithm (혼합 유전 알고리즘을 이용한 GDP/MINLP로 표현된 공정 최적화)

  • 송상옥;장영중;김구회;윤인섭
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.2
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    • pp.168-175
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    • 2003
  • A new algorithm based on Genetic Algorithms is proposed f3r solving process optimization problems formulated in MINLP, GDP and hybrid MINLP/GDP. This work is focused especially on the design of the Genetic Algorithm suitable to handle disjunctive programming with the same level of MINLP handling capability. Hybridization with the Simulated Annealing is experimented and many heuristics are adopted. Real and binary coded Genetic Algorithm initiates the global search in the entire search space and at every stage Simulated Annealing makes the candidates to climb up the local hills. Multi-Niche Crowding method is adopted as the multimodal function optimization technique. and the adaptation of probabilistic parameters and dynamic penalty systems are also implemented. New strategies to take the logical variables and constraints into consideration are proposed, as well. Various test problems selected from many fields of process systems engineering are tried and satisfactory results are obtained.

On the Dominance - Diversity in the Forest Vegetation of Mt. Halla National Park (漢拏山 國立公園 森林植生의 優占度-多樣性에 關하여)

  • Yim, Yang-Jai;Lee, Jin-Hwa
    • The Korean Journal of Ecology
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    • v.14 no.3
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    • pp.257-271
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    • 1991
  • Two types in the species-importance, one type of carpinus laxiflora, carpinus tschonoskii, quercus serrata, quercus grosseserrata and pnus densiflora community and another type of abeies koreana community classified by zurich-montpellier method, were recognized based on the data from 81 sample plots. The forme species sequence-importance curves were coincidred with the ideal curve calculated by preston's lognormal-distribution theory(1948), with small variations among five communities, and the latter with that of motomura's niche pre-emption hypothesis(1932). It seems that plant community classified by phytosociological method based on the unit concept coincide with the vegetation type recognized by species population analyse based on the continuum concept and the dominance-diversity reflrcts on the difference in the coenocline among their plant communities.

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The Static and Dynamic Growth Patterns of High-Tech Ventures in Korea

  • Park, Sangmoon;Bae, Zong-Tae
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2001.10a
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    • pp.233-236
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    • 2001
  • This study explores on the static and dynamic growth patterns of high-tech ventures in Korea. We developed an integrative framework with target market (local vs. global), product/market maturity (existing vs. emerging), and technological capability (follower vs. pioneer). We also identified seven new ventures strategies as follows: i) reactive imitation, ii) proactive localization, iii) import substitution, iv) creative imitation, v) early market-entry, vi) global niche, and vii) global innovation. With five successful Korean new ventures, we found different competitive behaviors and performance among new venture strategic types. This study also observed two different growth patterns: growth through strategic replication and growth through strategic change. It depends on whether they are pursuing similar strategy over time or different strategy within for growth. In addition, we found that creative imitation plays a stepping-stone role in two-step internationalization processes. Although this study is exploratory and needs more empirical studies, it can provide new ventures with meaningful guidelines for growth and internationalization with a dynamic perspective.

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Coupling Particles Swarm Optimization for Multimodal Electromagnetic Problems

  • Pham, Minh-Trien;Baatar, Nyambayar;Koh, Chang-Seop
    • Proceedings of the KIEE Conference
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    • 2009.07a
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    • pp.786_787
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    • 2009
  • This paper proposes a novel multimodal optimization method, Coupling particles swarm optimization (PSO), to find all optima in design space. This method based on the conventional Particle Swarm Optimization with modifications. The Coupling method is applied to make a couple from main particle and then each couple of particles searches its own optimum by using non-stop-moving PSO. We tested out our method and other one, such as ClusteringParticle Swarm Optimization and Niche Particle Swarm Optimization, on three analytic functions. The Coupling Particle Swarm Optimization is also applied to solve a significant benchmark problem, the TEAM workshop benchmark problem 22

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Shotgun Phage Display of Lactobacillus casei BL23 Against Collagen and Fibronectin

  • Munoz-Provencio, Diego;Monedero, Vicente
    • Journal of Microbiology and Biotechnology
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    • v.21 no.2
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    • pp.197-203
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    • 2011
  • Lactobacilli are normal constituents of the intestinal microbiota, and some strains show the capacity to bind to extracellular matrix proteins and components of the mucosal layer, which represents an adaptation to persist in this niche. A shotgun phage-display library of Lactobacillus casei BL23 was constructed and screened for peptides able to bind to fibronectin and collagen. Clones showing binding to these proteins were isolated, which encoded overlapping fragments of a putative transcriptional regulator (LCABL_29260), a hypothetical protein exclusively found in the L. casei/rhamnosus group (LCABL_01820), and a putative phage-related endolysin (LCABL_13470). The construction of different glutathione S-transferase (GST) fusions confirmed the binding activity and demonstrated that the three identified proteins could interact with fibronectin, fibrinogen, and collagen. The results illustrate the utility of phage display for the isolation of putative adhesins in lactobacilli. However, it remains to be determined whether the primary function of these proteins actually is adhesion to mucosal surfaces.

Genetic algorithms with a permutation approach to the parallel machines scheduling problem

  • Han, Yong-Ho
    • Korean Management Science Review
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    • v.14 no.2
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    • pp.47-61
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    • 1997
  • This paper considers the parallel machines scheduling problem characterized as a multi-objective combinatorial problem. As this problem belongs to the NP-complete problem, genetic algorithms are applied instead of the traditional analytical approach. The purpose of this study is to show how the problem can be effectively solved by using genetic algorithms with a permutation approach. First, a permutation representation which can effectively represent the chromosome is introduced for this problem . Next, a schedule builder which employs the combination of scheduling theories and a simple heuristic approach is suggested. Finally, through the computer experiments of genetic algorithm to test problems, we show that the niche formation method does not contribute to getting better solutions and that the PMX crossover operator is the best among the selected four recombination operators at least for our problem in terms of both the performance of the solution and the operational convenience.

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Policies to Promote Green Economy Innovation in East Asia and North America

  • Barbier, Edward B.
    • STI Policy Review
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    • v.6 no.1
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    • pp.54-69
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    • 2015
  • Although there is progress in developing green sectors in North America and East Asia, the key challenge facing the expansion of economy-wide green innovation and structural change in these regions is the absence of relevant policy follow-up to the green stimulus enacted during the Great Recession. The boost to green sectors provided by such measures is waning quickly, given that much of the green stimulus focused on energy efficiency. The biggest obstacles to sustaining green growth in North America and East Asiaare major market disincentives, especially the under-pricing of fossil fuels and market failures that inhibit green innovation. A three-part strategy to overcome these obstacles would involve: first, removing fossil fuel subsidies; second, employing market-based instruments to further reduce the social costs of fossil fuel use; and third, allocating any resulting revenue to public support for green innovation and investments. Such a strategy would ensure that green growth is not about promoting niche green sectors but instigating economy-wide innovation and structural transformation in North America and East Asia.

In vitro methods to study the vascularization of natural and synthetic biomedical polymers

  • Kirkpatrick C. James;Fuchs Sabine;Motta Antonella;Santos Marina;Hermanns M. Iris;Unger Ronald E.;Reis Rui;Migliaresi Claudio
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.46-47
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    • 2006
  • Vascularization is essential for success in regenerative medicine. We have developed in vitro models to study how human microvascular endothelial cells (EC) and endothelial progenitor cells (EPC) colonize polymer scaffolds and express the endothelial phenotype, including angiogenesis. Examples are given of supportive growth and differeniation of EC on microfibre meshes of the silk protein fibroin and blends of starch with poly(epsilon-caprolactone), phenotypic markers being studied at both protein and mRNA level. Experimental models are also shown and concepts discussed to investigate how the stem cell niche, including that responsible for vascularization could be targeted, for example, by using engineered biodegradable polymer nanoparticles.

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