• 제목/요약/키워드: level of contribution

검색결과 1,093건 처리시간 0.23초

환경 중 유전독성물질 검색을 위한 자주달개비 생물검정 기법의 적용연구 (Biomonitoring the Genotoxicity of Environmental Pollutants Using the Tradescantia Bioassay)

  • 신해식
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 2004년도 춘계학술대회
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    • pp.47-60
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    • 2004
  • Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public from agents that can cause mutation and/or cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

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자주달개비 생물검정 기법을 이용한 환경오염 평가 (Assessment of Environmental Pollution with Tradescantia Bioassays)

  • 김진규;신해식
    • 한국환경생물학회:학술대회논문집
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    • 한국환경생물학회 2004년도 학술대회
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    • pp.1-15
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    • 2004
  • Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public firom agents that can cause mutation anuor cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

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STELLAR POPULATIONS IN EXTERNAL GALAXIES

  • Whang, Yun-Oh;Lee, Sang-Gak
    • 천문학회지
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    • 제22권1호
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    • pp.1-24
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    • 1989
  • By applying population synthesis method, stellar populations in the nuclei of M31 and M32 are studied. We obtained five and four models for M31 and M32 respectively, for different main sequence turn-offs and keeping the astrophysical constraints as loose as possible. The best models for M31 and M32 are thought to have G0-5 and F5-8 main sequence trun-offs respectively. These models show that the main sequence stars outnumber the giants, which indicates the dwarf-dominance in external galactic nuclei. Even though there are some computational difficulties because of non-uniqueness in solution, two major points can be pointed out when compared to the previous papers. First, the ultraviolet deficiency expected from the conventional metal rich population models is not detected in our models, Instead ultraviolet radiation turns out to be somewhat higher than that of observation. Second one is the minor contribution from the Super Metal Rich (SMR) K giants to the integrated light of the program galaxies. That is, in our models, the SMR contribution is at best the same level as normal giants contrary to the SMR dominance of previous models. Since the loose astrophysical constraints are the major difference of our study from the previous ones, one should re-examine carefully for their validity further.

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수산자원량 추정을 위한 생물경제 모델의 적합성평가 (Determining Appropriate Bioeconomic Models for Stock Assessment of Aquatic Resources)

  • 표희동
    • 수산경영론집
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    • 제33권2호
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    • pp.75-98
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    • 2002
  • As a contribution to developing fishery stock assessment, optimum sustainable yield and its international standards such as MSY, MEY, and dynamic MEY for six recommended fisheries are developed using bio-economic models. For selecting the appropriate model, five models - Schaefer, Schnute, Walters and Hilborn, Fox, and CY&P models are tested in effort and catch data of six species. Surprisingly all the models except the CY&P model failed to satisfy statistical standards such as goodness-of-fitness and reliability. Generally, the CY&P model holds good fitness and statistically significant level for all of six fisheries. However, the CY&P model for squid, where the intrinsic growth rate is high, could not explain MSY, MEY, and dynamic MEY appropriately. This study makes a contribution to develop the modified model for the intrinsic growth rate of 1. The reformulated model represents the results reasonably even though the estimated equation has not good fitness. Although most of the CY&P models appear to have good fits and validated results for some cases, these models also seem to be quite sensitive to parameters which means a more stable model should be developed and data should carefully be handled. In particular biological and technical interactions such as multispecies, predator prey relationship, age structure and mortality should be taken into account. In addition, economic factors and fishing efforts such as price, cost, technical change and a reasonable function of fishing input should simultaneously be considered.

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How have retailers led the HMR industry in Japan and UK?

  • CHO, Young Sang
    • 융합경영연구
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    • 제9권6호
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    • pp.25-38
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    • 2021
  • Purpose: This study is aiming at providing researchers and practitioners with new insights to analyse how retailers have made a contribution to the growth of HMR market in Japan and UK. Research design: The second section will look at the definition of HMR, and then, introduce each county's case, while analysing how retailers have developed the HMR market and illustrating some implications. Finally, the authors will draw a conclusion. Results: Retailers have established the retailer brand development department with the sophisticated retail information system which has made a considerable contribution to the growth of the HMR market. Also, it enables retailers to accumulate retail knowledge associated with ready-to-eat meals and train top-level experts, whilst helping them to build the trustworthy supply chain relationships by sharing the POS data with food manufacturers. Consequently, the cooperation with food manufacturers has enhanced in the HMR market in both Japan and UK, on the basis of sophisticated delivery system as well as the concept of innovation into the HMR sector. Conclusions: Retailers have to benchmark Japanese and British retailers' Knowledge to grow ready meal market in Korea and invest their marketing resources in developing various HMR foods, on the basis of innovative thinking.

남북한 주민의 건강수준 비교연구 (Comparative Study of the Health Status of Two Koreas)

  • 김영치
    • 보건행정학회지
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    • 제7권1호
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    • pp.155-182
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    • 1997
  • Objectives : This study was designed to compare North Korea and South Korea in measures of the quality of life (physical quality of life index and human development index) and to investigate the impact of selected medical and socioeconomic factors on PQL variables. Data and Methods : The World Bank, the United Nations Development Programme, and Population Reference Bureau were the principal sources of statistical data of 121 countries. Variables included infant mortality, life expectancy at birth, literacy rate, secondary school enrollment (male and female), GNP per capita, population per doctor, daily calorie supply per capita, and a composite PQL index. The Ordinary Least Square model was employed for cross-countries analysis. Findings : Both countries under quite different political and economic systems saw big improvememts in the quality of life, reducing mortality and prolonging life expectancy during the past three decades. In recent decad, however, North Korea has experienced abrupt exacerbation in the quality of life. Significant improvements in infant mortality of the population wer attributable mainly to GNP per capita and the secondary school enrollemt of female. The principal predictors of life expectancy at birth were population per doctor, infant mortality, and literacy rate. The secondary school enrollment of female and population per doctor were significantly associated with improvements in the physical quality of life index (PQLI). Conclusion : The results of this study confirmed a point illustrated by other studies : The association between quality of life as a measure of health status and socioeconomic factors was strong and positive. The important contribution of educational attainment in general, female education level in particular to improvements in the quality of life deserves good news for building an integrated health care system in the reunified Korea, taking into account the high level of education two koreas are enjoying. Meanwhile, when a sharp drop in the quality of life has been observed in North Korea under serious economic difficulties and food shortage in recent decade, the significant contribution of economic development to improvements in the quality of life poses bad nows for reunifying Korean health care in economic terms.

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중.고등학생 및 대학생의 과학 관련 태도에 대한 비교 연구 (Comparative Study on the Attitudes toward Science of Middle School, High School, and University Students)

  • 심규철;김현섭;박영철
    • 한국과학교육학회지
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    • 제21권3호
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    • pp.558-565
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    • 2001
  • 본 연구에서는 중학교, 고등학교, 과학 관련 전공 대학생들의 과학 관련 태도 수준에 대해 비교 분석하였으며, 그 결과를 바탕으로 미래 과학 교육을 위한 시사점을 제공하고자 하였다. 연구 대상은 중학생 70명,고등학생 72명, 대학생 95명 등 총 237명이었다. 과학관련 태도의 조사는 리커르트 방식(1에서 5점 척도)으로 응답하는 도구를 개발하여 사용하였는데, 과학적 탐구, 과학 투자의 중요성, 과학자의 평범성, 과학의 사회적 가치 등 4개 영역에서 총 20 문항을 구성하였다. 과학 관련 태도 4개 영역 중 가장 높은 태도수준을 나타낸 영역은 과학 투자의 중요성이었으며,가장 낮은 태도 수준을 나타낸 영역은 과학자의 평범성으로 조사되었다. 과학 관련 태도 점수는 중학교,고등학교, 대학교 등 학교 급간에 따라서는 유의미한 차이를 나타내지 않았으나, 성별에 따라서는 유의미한 차이를 나타내었다. 과학 관련 분야의 인재 양성을 위해서는 중등교육 및 대학 교육의 교육 과정 개발 시 과학 관련 태도를 배양시키기 위한 방안이 요구된다.

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Small Ruminants: Imperatives for Productivity Enhancement Improved Livelihoods and Rural Growth - A Review

  • Devendra, C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제14권10호
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    • pp.1483-1496
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    • 2001
  • Small ruminants form an important economic and ecological niche in small farm systems and agriculture. Their current low level of contribution is dismal, and is not commensurate with the potential capacity for higher levels of production. The context for productivity enhancement and increased socio-economic contribution relates to large sizes of small ruminant populations; wide distribution across various agro-ecological zones and production systems; and diversity of breeds, where 66% of all goat and 57% of sheep breeds in Asia are found in China, India and Pakistan. The advantages and disadvantages of small ruminants over larger ruminants are enumerated with reference to adaptation and environment, small size, production systems and products and interactions with the environment. Discussion focuses especially on efficiency of meat production and niche markets for higher-priced goat meat, and inefficient marketing systems given an estimated 40-45% loss of income to farmers presently. Increasing the quantity of meat produced is related to live weight and the total number of animals at Slaughter, which in turn, depend on the total number of offsprings weaned and lifetime productivity. At the national level, priority attention is essential to build up numbers in concerted breeding programmes, selection for efficiency of reproduction and meat production, and improvements to make traditional markets and marketing systems to respond to the changing environmental and consumer preferences. Post-production systems are neglected and improvements are associated with collection, handling, marketing, slaughter facilities and consumer requirements. Potential opportunities to expand and benefit from integrating small ruminants into annual and perennial cropping systems remain largely unexplored. Important development imperatives include choice of species and better use of available breeds, appropriate production systems that match available feed resources, and linkages between production, products and by-products to markets. Affirmative action is necessary, backed by official policy support, institutional commitment and increased resource use, that can target poverty and directly benefit the poor, and shift subsistence production to a more market-oriented opportunity. These efforts together constitute the challenges for both the owners and producers of small ruminants in the immediate future, as also the will to accelerate increased productivity, improve their livelihoods and promote rural growth.

The Impact of the Regional Comprehensive Economic Partnership (RCEP) on Intra-Industry Trade: An Empirical Analysis Using a Panel Vector Autoregressive Model

  • Guofeng Zhao;Cheol-Ju Mun
    • Journal of Korea Trade
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    • 제27권3호
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    • pp.103-118
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    • 2023
  • Purpose - This study aims to examine the dynamic relationship between the variables impacted by the Regional Comprehensive Economic Partnership (RCEP) and the level of intra-industry trade among member states, with the ultimate objective of deducing the short- and long-term effects of RCEP on trade. Design/methodology - This study focuses on tariffs, GDP growth rates, and the proportion of regional FDI to total FDI as research variables, and employs a panel vector autoregression model and GMM-style estimator to investigate the dynamic relationship between RCEP and intra-industry trade among member countries. Findings - The study finds that the level of intra-industry trade between member states is positively impacted by both tariffs and intra-regional FDI. The impulse response graph shows that tariffs and FDI within the region can promote intra-industry trade among member countries, with a quick response. However, the contribution rates of tariffs and intra-regional FDI are not particularly high at approximately 1.5% and 1.4%, respectively. In contrast, the contribution rate of GDP growth can reach around 8.5%. This implies that the influence of economic growth rate on intra-regional trade in industries is not only long-term but also more powerful than that of tariffs and intra-regional FDI. Originality/value - The originality of this study lies in providing a new approach to investigating the potential impact of RCEP while avoiding the limitations associated with the GTAP model. Additionally, this study addresses existing gaps within the research, further contributing to the research merit of the study.

PSA를 이용한 연구용 원자로 안전성 향상 방안 도출 (Design Improvement to a Research Reactor for Safety Enhancement using PSA)

  • 이윤환
    • 한국안전학회지
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    • 제33권5호
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    • pp.157-163
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    • 2018
  • This paper describes design improvement to a research rector for safety enhancement using Probabilistic Safety Assessment (PSA). This PSA under reactor design was undertaken to assess the level of safety for the design of a research reactor and to evaluate whether it is probabilistically safe to operate and reliable to use. The scope of the PSA reported here is a Level 1 PSA, which addresses the risks associated with the core damage. The technical objectives of this study were to identify accident sequences leading to core damage and to derive design improvement from the dominant accident sequences through the sensitivity analysis. The AIMS-PSA and FTREX were used for the this PSA of the research reactor. The criterion for inclusion was all sequences with a point estimate frequency greater than a truncation value of 1.0E-14/yr. The final result indicates a point estimate of 6.79E-05/yr for the overall Core Damage Frequency (CDF) attributable to internal initiating events for the research reactor under design. Based on the dominant accident sequences from the PSA, the seven kinds of sensitivity analysis were performed and some design improvement items were derived. When the five methods to improve the safety were all applied to the reactor design and emergency operating procedure, its risk was reduced to about 1.21E-06/yr from 6.79E-05/yr. The contribution of LOCA and LOEP with high CDF were significantly reduced by the sensitivity analysis. The safety of the research reactor was well improved and the risk was reduced than before adapting the design improvement gotten from the sensitivity analysis. The present study indicated that the research reactor has the well-balanced safety in regard to each initiating event contribution to CDF. The PSA methodology is very effective to improve reactor safety in a conceptual design phase and especially, Risk-informed design(RID) is very nice way to find the deficiencies of research reactor under design and to improve the reactor safety by solving them.