검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 17

        1.
        2023.10 구독 인증기관·개인회원 무료
        최근 국내에서는 꿀벌 대량소실 현상이 2022년부터 전국적으로 발생하고 있다. 우리나라 뿐 만 아니라, 전세계 적으로 양봉산업에 큰 위협이 되고 있는 봉군붕괴현상은 2016년 미국에서 세계 최초로 보고되었다. 국내에서는 2022년 민관 합동조사 결과, 이상기온, 응애, 말벌 등이 주요 원인으로 지목되었다. 대량소실 현상을 보인 양봉농 가와 정상 농가의 병원체 검출 비교 결과, 유의성있게 검출이 증가되는 병원체는 발견되지 않았다. 그러나, Tyrophagus mite, Trypanosome, Lake Sinai virus, Apis mellifera filamentous virus 등의 신종 응애, 원충 및 바이러 스 감염이 추가로 확인되었다. 국내에서 새롭게 감염이 확인된 기생충과 병원체가 대량소실, 나아가 봉군붕괴현 상에 직간접적으로 영향을 주었을 것으로 사료되며, 지속적인 조사와 연구개발을 통해 기후등 환경변화에 따른 신종 질병 검색과 대책을 마련해야 할 것이다.
        3.
        2019.03 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        To develop flexible adsorbents for compact volatile organic compound (VOC) air purifiers, flexible as-spun zeolite fibers are prepared by an electrospinning method, and then zeolite particles are exposed as active sites for VOC (toluene) adsorption on the surface of the fibers by a thermal surface partial etching process. The breakthrough curves for the adsorption and temperature programmed desorption (TPD) curves of toluene over the flexible zeolite fibers is investigated as a function of the thermal etching temperature by gas chromatography (GC), and the adsorption/desorption characteristics improves with an increase in the thermal surface etching temperature. The effect of acidity on the flexible zeolite fibers for the removal of toluene is investigated as a function of the SiO2/Al2O3 ratios of zeolites. The acidity of the flexible zeolite fibers with different SiO2/Al2O3 ratios is measured by ammonia-temperature-programmed desorption (NH3-TPD), and the adsorption/desorption characteristics are investigated by GC. The results of the toluene adsorption/desorption experiments confirm that a higher SiO2/ Al2O3 ratio of the flexible zeolite fibers creates a better toluene adsorption/desorption performance.
        4,000원
        4.
        2018.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Clithon retropictus has been protected by the Ministry of Environment as an endangered species since 1998 and has been listed on the state red list of endangered species category II. It is viewed as a representative for all endangered species in the northeastern coastal waters of Korea. Most of the habitats of C. retropictus have been found to be in an unstable state because of development projects such as road construction, small stream development, irrigation for securing agricultural water, and flood prevention. These habitats are damaged by small stream maintenance projects and development, and the risk of damage is increasing and active efforts are needed in order to protect them. Although the Ministry of Environment is striving to preserve this endangered species, the habitat of C. retropictus is still facing external threats because it spreads to only a small area at high densities. Therefore, in order to protect the habitat of C. retropictus, a level II endangered species, it is urgent to make an effort to minimize habitat damage and to take measures for its protection.
        4,000원
        6.
        2013.10 구독 인증기관·개인회원 무료
        Tyrophagus putrescentiae (Tp) as a storage mite inhabitats in stored grains, hay, and straw at agricultural areas. T. putrescentiae stimulates an immune response and triggers inflammatory cytokines release, and thus it is a source of allergen that sensitize and induce allergic reactions. Also, T. putrescentiae has been reported to cause asthma and atopic disease by cross-reactivity with Dermatophagoides pteronyssinus (Dp). The study on T. putrescentiae in human monocytic THP-1 cells is not enough to understand cytokine expression and pathological mechanisms. The aim of this study is to investigate the effect of T. putrescentiae extract (TpE) on production of inflammatory cytokines and expression of mRNA level in THP-1 cells. THP-1 cells are treated with TpE and supernatants were analyzed for the production of cytokines using enzyme-linked immunosorbent assay (ELISA). mRNA level in the culture cells was measured by a reverse transcriptase-polymerase chain reaction (RT-PCR). As a result of this study, TpE significantly induced secretion of interleukin-6, interleukin-8, and monocyte chemotactic protein-1 (MCP-1) in THP-1 cells in time- and dose-dependent manner. These results suggest that TpE may play a role in contributing to inflammatory disease through stimulation of immune cell. Further research of T. putrescentiae is needed to understand the elucidation of the pathogenic mechanism.
        7.
        2012.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A fabrication method to improve the processability of thermoplastic carbon nanotube (CNT) mat composites was investigated by using in-situ polymerizable and low viscous cyclic butylene terephthalate oligomers. The electrical conductivity of the CNT mat composites strongly depended on the compression pressure, and the trend can be explained in terms of two cases, low and high compression pressure, respectively. High CNT mat content in the CNT mat composites and the surface of the CNT mat composites with fully contacted CNTs was achieved under high compression pressure, and direct contact between four probes and the surface of the CNT mat composites with fully contacted CNTs gave resistance of 2.1Ω. In this study the maximum electrical conductivity of the CNT mat composites, obtained under a maximum applied compression pressure of 27 MPa, was 11 904 S m-1, where the weight fraction of the CNT mat was 36.5%.
        4,000원
        9.
        2020.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study suggests an alternative to the conventional collaborative filtering method for predicting consumer choice, using case-based reasoning. The algorithm of case-based reasoning determines the similarity between the alternative sets that each subject chooses. Case-based reasoning uses the inverse of the normalized Euclidian distance as a similarity measurement. This normalized distance is calculated by the ratio of difference between each attribute level relative to the maximum range between the lowest and highest level. The alternative case-based reasoning based on similarity predicts a target subject’s choice by applying the utility values of the subjects most similar to the target subject to calculate the utility of the profiles that the target subject chooses. This approach assumes that subjects who deliberate in a similar alternative set may have similar preferences for each attribute level in decision making. The result shows the similarity between comparable alternatives the consumers consider buying is a significant factor to predict the consumer choice. Also the interaction effect has a positive influence on the predictive accuracy. This implies the consumers who looked into the same alternatives can probably pick up the same product at the end. The suggested alternative requires fewer predictors than conjoint analysis for predicting customer choices.
        10.
        2018.11 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study examined the effects of startup firm's knowledge assets on the effectiveness of their sales strategies, efficiency of sales activities, and management performance, after categorizing these assets into customer knowledge assets and technology knowledge assets. Furthermore, the moderating effects of promotion focus by CEOs and sales managers of startup firms were analyzed. For the analysis, dyadic questionnaire surveys were conducted targeting the CEOs and sales managers of startup firms established at the Gyeongnam Technopark and the KAIST Technology Business Incubation Center in Korea. Hypotheses were verified through structural equation modeling, and moderating effects were identified through ANOVA. CEO's customer knowledge asset strengthened their effectiveness of sales strategies, and sales manager's technology knowledge asset strengthened the efficiency of their sales activities. Also, CEO's effectiveness of sales strategies and sales manager's efficiency of sales activities have been found to enhance startup firm's management performance. Meanwhile, the moderating effect of promotion focus strengthened CEO's effectiveness of sales strategies through CEO's customer knowledge asset and interaction as CEO's promotion focus level increased, but promotion focus of sales managers did not have any significant interaction effect. This study provides implications by offering empirical evidence on startup firms with regard to knowledge assets.
        15.
        2012.07 서비스 종료(열람 제한)
        Geneally, rice seeds regardless indica or japonica are showing low germination ratio or completely lost germination ability together with lost of good eating quality under high temperature and humidity conditions. Thus, this study was designed to evaluate a longevity for conservation of good eating quality during long term storage in rice. For the longevity evaluation, germination ability was studied after 5 days of high temperature and humidity stress (50℃/RH 95%). Dharial, originated from Bangladesh and showing weedy type with red pericarp, was selected as a good donor for longevity genes. A mutant was developed from Dharial through EMS mutagenesis and two populations of Dharial/4*Ilmibyeo and Dharial/4*Gopumbyeo were also developed for genetic study. In the 2-DE analysis followed by MALDI-TOF MS with wild and mutant lines, several candidate genes were identified. In the longevity test of two populations, a few lines showing good germination ability after high temperature and humidity stress were selected and subjected to confirm the relationships between longevity and conservation of good eating quality under long term storage.
        16.
        2010.04 KCI 등재 서비스 종료(열람 제한)
        An unbalance of rice productions and consumptions caused serious problems in both of agricultural area and grain market of korea. In recently, various efforts for rice processing products such as rice noodles and rice wines are in progress to overcome the unstable rice market. Among them, waxy rice is predominant items in processing rice. However, varietal features of starch viscosity are not considered in the processing industries and rice breeding field. In this study, 12 waxy rices and 2 cultivars Ilmibyeo(japonica) and IR72(Indica) were studied for physicochemical and amylogram to characterize the use of waxy rices. The amylose contents of waxy rices were from 7.1 to 8.1% with soft gel consistency and relatively low alkali digestion value(1.4% KOH) compare to Ilmibyeo. In the amylogram analysis(RVU) of waxy rices, unlikely normal rices, very fast peak time(about 3.5 min.) was obtained compare to that of 6.2 min. of Ilmibyeo. And 2 to 3 groups were classified based on peak viscosity and consitency of RVU. Wangchal, Odorokimochi and Hangangchal showed relatively high peak viscosity seemed not suitable for rice cake due to the hardness speed. And most of waxy rices developed in korea were believed to be suitable for oil fried cakes(Hankwa) because of a certain grade of starch degradation speed. And Mochiminori and Midoromochi originated from japan could be a good sources in waxy rice breeding program to improve the cooking properties especially in slow down of hardness speed with very low peak viscosity, hot viscosity and cool viscosity.