• 환경생물
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• 제37권3호
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• pp.335-342
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• 2019

The purpose of this study was to investigate the toxic effects of zinc in collembolan Paronychiurus kimi at the individual (survival and juvenile production) and population (population growth and age structure) levels after 28 days of exposure in artificially spiked soil. These toxic effects were interpreted in conjunction with the internal zinc concentrations in P. kimi. The EC₅₀ value for juvenile production based on the total zinc concentration was 457 mg Zn kg^-1 dry soil, while the LC₅₀ value for adult survival and r_i=0 value for population growth were within the same order of magnitude (2,623 and 1,637 mg Zn kg^-1 dry soil, respectively). Significant differences in adult survival, juvenile production, and population growth compared with the control group were found at concentrations of 1,500, 375, and 375 mg Zn kg^-1 dry or higher, respectively, whereas significant differences in the age structure, determined by the proportion of each age group in the population, were observed in all treatment groups. It appeared that the internal zinc level in P. kimi was regulated to some extent at soil zinc concentrations of ≤375 mg Zn kg^-1 dry soil, but not at high soil zinc concentrations. These results indicate that, despite zinc being regulated by P. kimi, excess zinc exceeding the regulatory capacity of P. kimi can trigger changes in the responses at the individual and population levels. Given that population dynamics are affected not only by individual level but also by population level endpoints, it is concluded that the toxic effects of pollutants should be assessed at various levels.

• 한국초등과학교육학회지:초등과학교육
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• 제22권1호
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• pp.81-96
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• 2003

The purpose of this study is to draw up the promoting plan of science preference by survey and analysis of the preference for science of the elementary students. The preference for science is defined theoretically with three categories ; they are emotional response, behavioral response and value establishment. Causal factors of the science preference were composed of individual factor, educational factor and social factor. According to this theoretical model, a questionnaire was developed, and administered to 696 students of 4,5,6 grade of randomly selected eight elementary schools all over the nation. Elementary students liked science, but they didn't want to select their future job in science-technology area. The science preference of boys was higher than that of girls. The science preference of 4th grade students was higher than that of 5th and 6th grade students. Individual factor affected the curiosity. learning interest, subject accomplishment on the science and course selection in life. Educational factor not only directly affected the curiosity. learning interest, value establishment and belief of the science but also indirectly affected the individual factor and social factor. Therefore, educational factor was the most important on the science preference. Social factor only affected the value establishment and belief on the science. Elementary students wanted to team science through experiment and they wanted science to be easier than that of now. On the analysis of result, the promoting plan of the science preference was suggested.

• 한국경제지리학회지
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• 제17권3호
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• pp.482-501
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• 2014

이 연구는 2013년 개별공지시가 자료를 활용하여 대구시 중구를 사례로 대도시 도심의 토지용도별 지가구조를 분석하였다. 분석결과, 지가구조가 토지용도에 따라 상당한 차이가 있는 것으로 밝혀졌다. 도심의 지가는 좁은 공간에도 불구하고 필지에 따라 변동성이 매우 크지만, 이것은 상업용지에 해당하는 것으로 주거용지나 주상복합용지에는 해당하지 않는다. 지가의 거리조락 역시 상업용지는 매우 크게 나타나지만, 주거용지나 주상복합용지는 거리조락 현상이 거의 없다. 주거용지와 주상복합용지는 지가최고점(PLVI)으로부터 가까울수록 지가가 오히려 하락하는 분화구 현상이 발견된다. 선형화한 지가함수의 회귀식에서도 상업용지와 업무용지는 지가의 거리 설명력이 크지만 주거용지나 주상복합용지는 거리 설명력도 미미하고, 특히 기울기가 음이 아닌 양의 값을 갖는다. 따라서 지금까지 일반적으로 상정되어 온 지가구조는 상업용지에는 유효하지만, 주거용지나 주상복합용지에는 유효하지 않다고 할 수 있다. 그러나 지가함수에 의한 토지용도의 분화 예측은 실제 토지이용 상황에 상당히 부합하여 알론소의 입찰지대이론의 현실적 적합성이 확인된다.

• 한국의류학회지
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• 제34권9호
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• pp.1491-1503
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• 2010

This study examines the characteristics of consumers on the ambivalent clothing consuming behavior and the relationship of relevant variables. The data were obtained from 400 females over 20 years old who lived in the cities of Daejeon or Seoul in October in 2009. The values consist of four dimensions: success-oriented value, social value, family-oriented value, and individual value. Value-conscious consumption consists of two dimensions: emotional value-conscious consumption and functional value-conscious consumption. The aforementioned four dimensions of value have positive effects on ambivalent clothing consuming behavior. In addition, emotional value-conscious consumption has a significant relationship on all 5 types in ambivalent clothing consuming behavior. The findings of this study are expected to be used to find niche markets and establish advanced advertising strategies.

• 한국임상수의학회지
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• 제22권3호
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• pp.198-201
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• 2005

이 연구의 목적은 BUN 및 혈청 creatining, total protein, albumin과 glucose의 장기간에 걸친 개체 내 변이를 산정하여, 각각의 critical difference를 구성하는 것이다. 임상적으로 건강한 20마리의 개에서 일주일에 한번씩 총 8주간 채혈하여, 장기간에 걸친 개체 내 변이를 구하고, critical difference를 산출하였다. BUN은 9.01 mg/dl, 혈청 creatining은 0.52 mg/dl, total protein은 0.99 g/dl, albumin은 0.39 g/dl, glucose는 20.64 mg/dl로 critical difference가 산출되었다. 동일한 개에서 연속적으로 측정된 검사항목 치가 critical value보다 차이가 적으면, 이 차이는 생리적인 변화에 기인한다고 할 수 있으며, critical value보다 차이가 크면, 다른 요인, 즉 질병의 진행이나 다른 동반된 질병의 존재를 의미한다고 할 수 있다.

• 한국ITS학회 논문지
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• 제22권1호
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• pp.52-64
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• 2023

차내 혼잡은 대중교통 이용자들의 통행의 질과 관련된 주제라고 할 수 있다. 차량의 제한된 용량과 배차간격 등의 이유로 주로 이용수요가 많은 교통수단 및 운영노선에서 차내 혼잡이 발생되며 이는 실제로 이용자들이 경험하는 통행시간의 가치에 차이를 유발시킨다. 본 연구에서는 오후 첨두시 분석노선 광역버스를 이용하는 개별 통행자의 스마트카드 자료 정보를 기반으로 차내 혼잡에 따른 개별 통행자의 시간가치를 추정하였다. 특히, 차내 혼잡이 개별 통행자가 느끼는 시간가치에 미치는 영향의 크기와 그 형태에 대해서 정교하게 분석하기 위해 Box-Cox transformation로 변환한 변수를 포함하여 모형을 구축하였다. 추정 결과에서 도출된 혼잡승수를 이용하여 2층 버스 도입 시 차내 혼잡 감소에 따른 편익을 산정하였으며 이를 통해 본 연구에서 제시하고 있는 추정 결과의 유의미성과 적용방안에 대해 논의하였다.

• 지식경영연구
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• 제16권1호
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• pp.117-142
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• 2015

Recently, the personal cloud computing service has been being spotlighted as an individual tool of productivity enhancement. However, compared to the rosy forecast, its diffusion rate in the domestic (Korean) market is much slower than expected. In order to find the reason for the slow growth of personal cloud computing service, we attempt to identify influencing factors on user's adoption resistance, while most prior research has focused on the factors affecting its adoption. Based on both the person-technology fit model and the privacy calculus model, we propose technostress and perceived value as key antecedents of adoption resistance. In addition, we identify (1) technical (pace of change and complexity) and personal (self-efficacy) influencing factors on technostress, and (2) beneficial (perceived mobility and perceived availability) and harmful (perceived vulnerability) influencing factors on perceived value. To validate our research model, 133 individual samples were gathered from undergraduate and graduate students who had actual experience of using at least one of personal cloud computing services. The results of the structural equation modeling confirm that both technostress and perceived value have significant effects on adoption resistance, but they have different influencing mechanisms to different types of adoption resistance (indifference, postponement, and rejection). Theoretical and practical contributions are discussed in the conclusion.

• 인터넷정보학회논문지
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• 제6권2호
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• pp.25-35
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• 2005

실시간 스케줄링 알고리즘에서는 비율단조(RM) 스케줄링 알고리즘과 마감시한(EDF) 스케줄링 알고리즘이 가장 일반적으로 사용되고 있다. 이러한 알고리즘에서는 태스크 집합의 전체 이용율 값을 가지고 수행 가능성을 판별하였다. 그러나 임의의 태스크에서 이용율 값이 초과되면 개별 태스크의 한계성을 전혀 예측할 수 없는 문제점이 있었다. 본 논문에서 제안한 알고리즘은 이용율 값이 초과한 태스크를 예측하고, 개별 태스크의 이용율 값을 기반으로 스케줄링 가능성 여부를 판단하는 방법을 제시하였다. 또한, 실시간 시스템에서 스케줄링 가능성 검사의 한계성을 시뮬레이션을 통해 예측하고 결과를 분석하였다.

• 대한가정학회지
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• 제40권10호
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• pp.161-176
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• 2002

This study is a basic research for the estimation of the value of unpaid household labor within the national economy system to be reflected in the related policy-making. By measuring economic value of unpaid household labor and estimating the ration to GDP, this study attempted to confirm the productivity of the unpaid household labor and thus contribute to the improvement of socio-economic status of women. Especially, it focused on the development of a standard of estimating unpaid household labor as a method applicable to the present economic and legal system. To organize the method of economic valuation of unpaid household labor and calculate the ration to GDP, this study used three approaches: replacement cost method individual function, replacement cost method generalist and opportunity cost method. Although the estimated result revealed that the economic value of unpaid household labor showed a great extent of deviation according to the estimating methods and the wage rate, total value of household labor ranged from one hundred and thirty eight to two hundred and thirty trillion wens, about 28-48% of GDP in Korea.

• 한국발생생물학회지:발생과생식
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• 제22권4호
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• pp.393-402
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• 2018

Genomic DNA was isolated from the Gracilaria vermiculophylla (GRV) and G. chorda (GRC) from Jangheung located in the southern sea of the Korean Peninsula, respectively and we performed clustering analyses, DNA polymorphisms and the genetic differences. The seven selected primers OPC-01, OPA-04, OPA-05, OPD-07, OPD-08, OPB-10, and OPD-16 generated average bandsharing (BS) value, the genetic distance and dendrogram. The size of DNA bands varies from 90 bp to 2,400 bp. The average BS value was $0.859{\pm}0.004$ within GRV and $0.916{\pm}0.006$ within GRC. The average BS value between two Gracilaria species was $0.340{\pm}0.003$, ranged from 0.250 to 0.415. The dendrogram obtained by the seven primers, indicates two genetic clusters. The genetic distance between two Gracilaria species ranged from 0.059 to 0.513. The individual VERMICULOPHYLLA no. 07 of GRV was genetically closely related to VERMICULOPHYLLA no. 06 of GRV (genetic distance=0.059). Especially, two entities between the individual VERMICULOPHYLLA no. 10 of GRV and CHORDA no. 22 of GRC showed the longest genetic distance (0.513) in comparison with other individuals used. Accordingly, as mentioned above, PCR analysis showed that the GRV was a little more genetically diverse than the GRC species. We convinced that this DNA analysis revealed a significant genetic distance between two Gracilaria species pairs (p<0.01).