• Mycobiology
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• 제44권3호
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• pp.162-170
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• 2016

In this paper, we demonstrate the ability of Arabidopsis thaliana to detect different mixtures of volatile organic compounds (VOCs) emitted by the common indoor fungus, Aspergillus versicolor, and demonstrate the potential usage of the plant as a bioindicator to monitor fungal VOCs in indoor air. We evaluated the volatile production of Aspergillus versicolor strains SRRC 108 (NRRL 3449) and SRRC 2559 (ATCC 32662) grown on nutrient rich fungal medium, and grown under conditions to mimic the substrate encountered in the built environment where fungi would typically grow indoors (moist wallboard and ceiling tiles). Using headspace solid phase microextraction/gas chromatography-mass spectrometry, we analyzed VOC profiles of the two strains. The most abundant compound produced by both strains on all three media was 1-octen-3-ol. Strain SRRC 2559 made several terpenes not detected from strain SRRC 108. Using a split-plate bioassay, we grew Arabidopsis thaliana in a shared atmosphere with VOCs from the two strains of Aspergillus versicolor grown on yeast extract sucrose medium. The VOCs emitted by SRRC 2559 had an adverse impact on seed germination and plant growth. Chemical standards of individual VOCs from the Aspergillus versicolor mixture (2-methyl-1-butanol, 3-methyl-1-butanol, 1-octen-3-ol, limonene, and ${\beta}-farnesene$), and ${\beta}-caryophyllene$ were tested one by one in seed germination and vegetative plant growth assays. The most inhibitory compound to both seed germination and plant growth was 1-octen-3-ol. Our data suggest that Arabidopsis is a useful model for monitoring indoor air quality as it is sensitive to naturally emitted fungal volatile mixtures as well as to chemical standards of individual compounds, and it exhibits relatively quick concentration- and duration-dependent responses.

• 융합보안논문지
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• 제15권2호
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• pp.19-24
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• 2015

웹3.0, 미래 인터넷 및 사물인터넷 등으로 인터넷 이용이 급증함에 따라 사용자와 웹서버들 사이의 상호 정보 교환을 통한 빅데이터들이 증가하고 있다. 이런 데이터들의 분석 결과들은 상업용 웹사이트의 경우 마케팅과 캠페인에 활용하고, 비상업용 사이트의 경우에도 사용자의 서비스 만족도 향상을 위한 기초자료로 이용된다. 본 논문에서는 웹사이트 분석을 위한 정량적 지표들을 제시하고 지표들 사이의 상관관계와 유의성 검정 분석을 통하여 최적화된 웹사이트 설계 방안을 제시한다. 138개의 웹사이트에 대한 분석 결과, 방문수와 순방문자 수, 페이지뷰 수와 평균 방문시간의 사이에는 각각 강한 양(+)의 상관관계가 존재하며, 방문당 페이지뷰 수 및 신규 방문 비율과 이탈률 사이에는 음(-)의 상관관계가 존재함을 알 수 있다. 특히, 웹사이트 방문자의 이탈률을 줄이기 위해서는 방문수와 순방문자 수를 높이기보다, 방문당 페이지뷰의 수와 신규 방문비율을 높이기 위한 전략이 요구된다.

• 마케팅과학연구
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• 제16권1호
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• pp.1-11
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• 2006

저작권의 거래 및 통제를 매우 낮은 비용으로 구현한 DRM(Digital Right Management)에 의해 디지털 컨텐츠의 유통에 획기적인 변화가 가능할 것으로 생각된다. 본 논문은 DRM 기술의 도입에 의해 개별 이용자가 유통의 주체가 되는 초유통(Super Distribution)의 적용 가능성과 다양한 가격설정 방식이 적용될 수 있다는 점에 주목하였다. 우선 초유통을 통해 이용자들의 정보획득비용을 감소시키고 이를 통해 수요를 증가시킬 수 있으며 컨텐츠 제작자 측면에서도 유통에 따른 비용을 크게 감소시킬 수 있음을 논하였다. 또한 DRM은 기존의 총량가격 방식 이외에 사용기간 또는 사용 횟수 등 다양한 기준에 따른 가격설정을 가능하게 하며 이를 통해 기업의 이윤과 소비자 총효용 모두 증가할 수 있음을 보였다. 이러한 DRM 기술의 특성은 디지털 컨텐츠 유통의 효율성을 증대시키고 컨텐츠의 질과 다양성 및 가격정책을 통한 사업자들간 차별화를 가능케 하여 산업의 동적인 성장을 가속화 할 수 있을 것으로 생각된다.

• 한국학교ㆍ지역보건교육학회지
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• 제5권
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• pp.11-23
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• 2004

The purpose of this study was to analyze the internet usage patterns among adolescents and to provide basic data for the development of internet addiction prevention program. The subjects of this study were 1169 students in middle and high school students in Seoul, Korea. Self-administered questionnaires were employed and data were analysed by SPSS 12.0. Major conclusions were as follows: 1. Most of the students were found to be the normal internet users. On the other hand, potential risk group was 8.2% and high risk group was 4.7%. Every students have had an experience of inter use. The 90.6% of the students' households had internet links. The percentage of students who were using internet more than 3 hours a day was 25.7%, and The most popular type of website was entertainment. 2. Male students showed greater percentages of potential risk and high risk group than female students. The students having parents in divorce, remarriage and separation were more likely to be in potential risk group than those having normal parents. The staying alone in home after school and small sleeping time were positively related to high level of internet addiction. 3. The characteristics of the students in potential risk and high risk group were longer duration of the internet use, internet use through the whole week, frequent internet use late at night, frequent use of pornographic site, main purpose of internet use for entertainment and shortage of rest during internet use. This study results had an limitation of generalizing to entire Korean adolescents because the sample of this study was middle and high school students living in Seoul. Future study was needed for the analysis of internet use behavior of the entire Korean adolescents, and for the identification of the accurate predictors for adolescents' internet addiction.

• Asian Pacific Journal of Cancer Prevention
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• 제17권4호
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• pp.2049-2053
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• 2016

Background: The LigaSure vessel sealing system has been proposed to save operation time and reduce intraoperative blood loss for various surgeries. However, its usage for gastric cancer is still controversial. The aim of the present meta-analysis was to compare the effectiveness of LigaSure with conventional surgery in gastrectomy. Materials and Methods: Sources were retrieved from the Cochrane Library, MEDLINE, EMBASE, SCOPUS and Google Scholar until February, 2015. All randomized controlled trials comparing LigaSure with conventional surgery in curative gastric cancer resection were selected. After data extraction, statistics were performed by Review Manager 5.1 software. Results: Three eligible randomized controlled trials were evaluated, with a total of 335 patients. The quality of the included trials was good, yet some methodological and clinical heterogeneity existed. There were no significant differences between the LigaSure and conventional groups in operative time (weighted mean difference [WMD], -22.95 minutes; 95% confidence interval [CI], [-59.75, 13.85]; P = 0.22), blood loss (WMD, -45.8 ml; 95% CI, [-134.5, 42.90]; P = 0.31), nor the incidence of surgical complications (odds ratio, 1.18; 95% CI, [0.68, 2.05]; P = 0.54). But there was a longer duration of hospital stay in LigaSure group (WMD, 1.41 days; 95% CI, [0.14, 2.68]; P = 0.03). Conclusions: All available randomized evidence has been summarized. LigaSure does not confer significant advantage over conventional surgery for curative gastric cancer resection. The usefulness of the device may be limited in gastrectomy. But, more trials are needed for further assessment of the LigaSure system for gastric cancer.

• 한국건설관리학회논문집
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• 제6권2호
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• pp.92-101
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• 2005

초고층 건축물은 층수의 증가에 비해서 공기의 증가가 작기 때문에 공기초과가 발생하기 쉽다. 최근 초고층 프로젝트의 증가에 따라 공정계획의 중요성이 증대되고 있으며 공정관리를 개선하기 위해서 공정계획 소프트웨어의 도입과 교육이 활발히 이루어지고 있다. 하지만 공정계획의 많은 부분은 아직도 계획자의 경험에 크게 의존하고 있다. 따라서 새로운 자재, 장비 및 공법이 도입되는 초고층 프로젝트는 공정 계획자의 경험이 부족할 경우, 경험 미숙으로 인한 공기초과가 발생하기 쉽다. 공정 계획자의 경험 미숙으로 인한 공정계획의 편차를 줄이기 위한 방안으로 본 연구에서는 전문가의 경험적 지식을 초고층 공정계획 작성에 활용하는 방안을 제안하였다. 사례연구에서는 초고층 골조공종을 대상으로 하여 본 연구에서 제안한 초고층 공정계획 지원시스템의 지식획득과 지식활용방안을 고찰하였다. 본 연구에서 제안한 지식획득과 지식활용을 토대로 초고층 공정계획 지원시스템을 구축하여 활용한다면 초고층 공정계획의 정확성을 높일 수 있으며 공기초과를 예방할 수 있을 것이다.

• 대한지역사회영양학회지
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• 제8권4호
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• pp.595-602
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• 2003

This study was carried out to investigate the status of the utilization of internet and dietary information by elementary school dietitians (total = 201) The results were summarized as follows: All subjects used the internet regularly and the major purpose they mentioned for using it was ″data search″ (72.3％). Those having a frequency of using the internet 6 to 7 times per week were 46.7％ of the subjects and the majority indicated the duration of their use of the internet was ″〈 2 hours″ (68.5％). They mainly used the internet at ″school″ (81.8％) , and their favorite search engines were ″Daum″ (41.1％) and ″Yahoo″ (34.7％). They stated that the organization that offered reliable internet information were those ″related to society and organizations″ (36.9％) and ″educational institutions″ (33.8％). Ninety-five percent of the subjects searched for dietary information mainly ″for public affairs″ (80.0％) Their degree of satisfaction when searching for information was high (78.7％). Those dissatisfied with internet sites when searching for dietary information give the following reasons: ″poor information″ (39.1％) and ″slow updates″ (25.4％). They acquired information on nutrition and health management mainly through ″the internet″ (63.6％) The most frequently requested information about public affairs was on ″Materials for nutritional education″ (38.6％) and ″up-to-date nutritional information″ (16.0％) . The desirable update periods for websites was ″1 -3 months″ (51.8％) and ″ < 1 month″ (30.6％), and the favorite site colors were ″blue″ (37.8％) and ″green″ (37.8％). The results of this study showed that, although the internet usage was high, the dietitians were dissatisfied with the information obtained. Therefore, the information donors should find out what kind of dietary information is needed by elementary school dietitians. (Korean J Community Nutrition 8(4) : 595-602, 2003)

• 수면정신생리
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• 제5권2호
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• pp.170-176
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• 1998

Nowadays light therapy is accepted practice in the treatment for Seasonal Affective Disorder. The author reviewed the practical aspects of light therapy, latest treatment research on optimal parameters of light therapy and the mechanisms of action of light therapy. Therapeutic efficacy of light therapy using light visors & dawn simulators has been suggested but further studies are needed to clarify the efficacy. The treatment most strongly supported by research studies is light therapy using a light box to administer bright white light (2500 lux for 2 hours or 10000 lux for 30 minutes). Although some patients may be selective responders to morning light exposure, the optimal timing of light exposure still remains controversial. In practice, generally the duration of exposure can be increased or decreased as necessary and also the timing of exposure can be splitted (e.g. AM/PM usage) if optimal response is obtained. For most, a positive response of light therapy is usually noted within $4{\sim}5\;days$ and optimal response is obtained within 2 weeks. Generally the relapse of symptom occurs within days of discontinuation of light therapy, so to prevent relapse, light therapy should be continued throughout the winter season for typical seasonal affective disorder. Side effects of light therapy appear to be mild and well tolerated. Several theories for the mechanisms of action of light therapy at the basis of seasonal affective disorder had been suggested but remain still controversial. Further studies on the optimal parameters and the mechanisms of light therapy help us to better understand and treat not only seasonal affective disorders but also chronobiological disorders and nonseasonal affective disorders.

• 한국임상수의학회지
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• 제20권3호
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• pp.351-356
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• 2003

The aim of this experiment was to study the calcium sulfate on early bone consolidation in distraction osteogenesis in the canine mandible. Twelve dogs were used and divided into control group (group A, 4 heads), sodium hyaluronate injection group (group B, 4 heads), mixture of calcium sulfate and sodium hyaluronate injection group (group C, 4 heads). Each group were subdivided into 3 weeks testing group (totally 6 heads) and 5 weeks testing group (totally 6 heads). Mandibular distraction was started at the 5th day after the mandibular osteotomy and continued for 10 days by 1 mm a day. After the distraction on the 10th day of mandibular distraction, 0.5 m1 saline in group A, 0.5 m1 sodium hyaluronate in group B, and 0.5 ml mixture of calcium sulfate and sodium hyaluronate in group C were each injected in mandibular distraction lesion. And X-ray examination, bone mineral density, and histopathological findings were examined. The radiological findings were the most radiopaque in group C, and the most radiolucent in group A in both 3 and 5 week testing group. The level of bone mineral density was also the highest in group C, and the lowest in group C in both 3 and 5 week testing group. The histopathological findings of new bone formation were the most remarkable in group C in both 3 and 5 week testing group. New bone formation of group A was not present in both 3 and 5 week testing group. In conclusion, calcium sulfate is a kind of material that can stimulate early bone formation and can shorten the duration of bone consolidation. And it can be effective in clinical usage.

• 디지털융복합연구
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• 제14권1호
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• pp.437-443
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• 2016

본 연구의 목적은 천식환자의 자가간호 프로그램이 자기효능감, 이행, 삶의 질에 미치는 효과를 알아보기 위한 예비연구이다. 본 연구는 단일군 전후설계이며 C대학병원에 입원 치료한 천식환자에게 직접 면담하여 연구목적을 설명하고 동의한 16명을 대상으로 2011년 2월 1일부터 3월 30일까지 천식관련지식, 흡입기, PEFR 사용 등에 관한 책자와 연구자의 시범으로 자가간호 프로그램을 제공하였다. 입원당일 사전조사를 실시하고, 퇴원 당일 일반적 특성과 질병관련 특성을 제외한 항목에 대해 동일한 질문지로 사후 조사를 실시하였고 수집된 자료는 SPSS 18.0 프로그램을 이용하여 Wilcoxon signed ranks test(Z) 비모수 통계량으로 분석하였다. 대상자는 자가간호 프로그램을 제공받은 후에 자기효능감(Z=-3.26, p=.001), 이행(Z=-3.52, p<.001), 삶의 질(Z=-3.41, p=.001)에서 통계적으로 유의한 차이를 보였다. 자가간호 프로그램은 천식환자에게 자기효능감, 이행, 삶의 질을 증진시킬 수 있는 프로그램으로 활용이 가능하다고 사료되며 추후 연구에서 중재기간, 연구디자인, 대상자 크기를 고려하기를 제언한다.