• 한국전자파학회논문지
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• 제16권8호
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• pp.848-854
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• 2005

본 논문에서는 국내 환경에 적용할 수 있는 EHF(44 GHz) 대역의 강우 감쇠 특성을 예측하기 위한 연구를 수행하였다. 일반적으로 10 GHz 이상에서 동작하는 무선 통신 시스템이 강우에 의한 영향을 많이 받는 것으로 알려져 있다. 이러한 강우 감쇠는 빗방울의 크기 분포를 통해서 예측이 가능하다. 따라서 무선 통신 시스템을 설계하거나 강우에 의한 감쇠 영향을 분석하기 위해서는 국내 환경에 적용 가능한 정확한 빗방울 크기 분포 예측 모델 개발이 중요하다. 본 논문에서는 충남대학교에서 측정을 통해 얻어진 데이터를 바탕으로 일반적인 확장 감마 분포를 이용하여 빗방울 크기 분포 예측 모델을 제시하였으며, 실제 강우 감쇠 측정 데이터와 잘 일치하는 결과를 얻었다.

• 셀메드
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• 제5권1호
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• pp.3.1-3.3
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• 2015

Pharmacovigilance is the study of the safety of drugs under the practical conditions of clinical usage in large communities. Aim of this study was to assess the pharmacovigilance awareness among a focus group of Ayurveda physicians in Sri Lanka who participated for their postgraduate studies. A questionnaire which was suitable for assessing the basic knowledge, attitude and the practice of pharmacovigilance was designed and submitted among group of Ayurveda physicians (n = 30) who participated for postgraduate studies in Institute of Indigenous Medicine, University of Colombo, Sri Lanka. Among participants30% of the subjects knew the term pharmacovigilance, 20% were aware of the unavailability of the National Pharmacovigilance Program for Ayurveda and Traditional Medicine in Sri Lanka, 70% believe about Adverse Drug Reactions (ADRs) may be occurred from Ayurveda medicine, 60% indicated that Most labeled counterfeit drugs, inappropriate use and standardization problems as the most important causes of ADRs associated with Ayurvedicdrugs, 70% physicians accepted their ignorance about pharmacovigilance and admitted that there was a need for better training of this subject and 90% admitted that there should be a national pharmacovigilance programme for Ayurveda medicines in Sri Lanka. We strongly suggest that there is an urgent need for a regular training and the introduce ADRs reporting system among the Ayurveda physicians. Also systematic pharmacovigilance programme is essential to build up for reliable information on the safety and effective practice of Ayurveda medicine in Sri Lanka.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2901-2904
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• 2014

The incidence of colorectal cancer has been increasing in many Asian countries including Malaysia during the past few decades. A physician recommendation has been shown to be a major factor that motivates patients to undergo screening. The present study objectives were to describe the practice of colorectal cancer screening by primary care providers in Malaysia and to determine the barriers for not following recommendations. In this cross sectional study involving 132 primary care providers from 44 Primary Care clinics in West Malaysia, self-administered questionnaires which consisted of demographic data, qualification, background on the primary care clinic, practices on colorectal cancer screening and barriers to colorectal cancer screening were distributed. A total of 116 primary care providers responded making a response rate of 87.9%. About 21% recommended faecal occult blood test (FOBT) in more than 50% of their patients who were eligible. The most common barrier was "unavailability of the test". The two most common patient factors are "patient in a hurry" and "poor patient awareness". This study indicates that colorectal cancer preventive activities among primary care providers are still poor in Malaysia. This may be related to the low availability of the test in the primary care setting and poor awareness and understanding of the importance of colorectal cancer screening among patients. More awareness programmes are required for the public. In addition, primary care providers should be kept abreast with the latest recommendations and policy makers need to improve colorectal cancer screening services in health clinics.

• 한국정보통신학회논문지
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• 제19권3호
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• pp.514-522
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• 2015

Microwave 무선 링크에서 거리에 따라 고 품질의 무선 링크를 지속적으로 보장하기 위해서는 무선 페이딩에 대한 고려가 필요하다. 링크 거리에 따라 동일한 고정 변조 방식을 적용할 경우 거리에 따른 페이딩 발생 확률의 증가로 장거리의 경우 요구 가용도를 지속적으로 보장하기 어렵다. 이를 위해 AM(Adaptive Modulation)이 유용하지만 AM만으로는 가변되는 전송량으로 인해 가용도 보장에 제한사항이 있다. 이전 연구에서 링크 거리를 고려한 전송 성능 향상 기법을 제안 했었다. 그러나, 이전 방법은 변수를 고려한 수식을 제시하지 않아 공통 적용을 위해서는 보완이 필요하였다. 본 논문에서는 장거리 무선 링크에서 가용도 보장을 위한 페이드 마진을 고려한 AM에 기반한 우선순위 트래픽 전송량 산출식을 제시하고 채널 대역폭 비교를 통한 최적화된 적응 전송 기법을 제안한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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• pp.74-77
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• 2006

This research is focused on the development of GIS Diagnostic SYSTEM to prevent accidents beforehand by inspecting the internal defects of GIS (Gas Insulated Switchgear) which is a main power-facility for substations. GIS Diagnostic SYSTEM is categorized as 'Real time on-line test type' and 'Portable test type' depending on the types of testing, it uses PD(partial discharge) which mostly incurs in GIS internal defects, to inspect. As of now, mostly foreign equipments are imported for use due to the lack of the technology localization, and these are installed and operated on only some parts of highly-graded GIS power-facilities such as in 76skv or 345kv for its being expensive. Furthermore, other than foreign equipments being costly, it also has a weak point of very long unavailability in case of Diagnostic system break-down while using, because it takes a comparatively long period of corrective maintenance precesses. We have localized to develop personal real-time multi -functional GIS Diagnostic system which can test on all GIS power-facility comprehensively and economically therefore overcome all these problems mentioned above, a market expansion is expected from the decrease of price and replacing the import equipments in the future. As the equipment was developed to be Personal for the simple ways of installing and utilizing, it can be operated without any complex cable installation like other existing GIS Diagnostic system requires, therefore also decrease the cost of cable installation.

• ALGAE
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• 제30권1호
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• pp.35-47
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• 2015

The marine sand-dwelling dinoflagellate Polykrikos lebourae possesses obvious gold-brown pigmented plastids as well as taeniocyst-nematocyst complex structures. Despite of the presence of the visible plastids, previous attempts to establish this species in culture all failed and thus the unavailability of cultures of this species has posed a major obstacle to further detailed exploration of ecophysiology of the dinoflagellate. Here, we isolated P. lebourae from sandy sediment of an intertidal flat on Korean western coast, successfully established it in culture, and have been maintaining the stock culture over the past 3 years. Using this stock culture, we explored phagotrophy and potential prey resources of P. lebourae, growth and grazing responses of P. lebourae to different prey organisms, the effect of prey concentration on growth and grazing rates and gross growth efficiency (GGE) of P. lebourae when fed three different prey organisms, and the growth kinetics of P. lebourae under different light regimes. P. lebourae captured prey cells using a tow filament and then phagocytized them through the posterior end. The dinoflagellate was capable of ingesting a broad range of prey species varying in size, but not all prey species tested in this study supported its sustained growth. GGE of P. lebourae was extremely high at low prey concentration and moderate or low at high prey concentrations, indicating that P. lebourae grows heterotrophically at high prey concentrations but its growth seems to be more dependent on a certain growth factor or photosynthesis of plastids derived from the prey. In the presence of prey in excess, P. lebourae grew well at moderate light intensity of $40{\mu}mol$ photons $m^{-2}s^{-1}$, but did not grow at dim and high (10 or $120{\mu}mol$ photons $m^{-2}s^{-1}$) light intensities. Our results suggest that the benthic dinoflagellate P. lebourae is an obligate mixotroph, requiring both prey and light for sustained growth and survival.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.236-236
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• 2017

Low soil pH causes from $H^+$ rhizotoxicity results in nutrients unavailability in the growing media, inhibits plant growth, development and reduces crop yields. The present study was carried out to reveal morpholophysiological and biochemical responses of wheat (Triticum aestivum L.) to acidity stress. Four wheat varieties viz. BARI Wheat-21, BARI Wheat-25, BARI Wheat-26 and BARI Wheat-30 were used in the study. Eight-day-old seedlings were exposed to different pH levels (3.5, 4.5, 5.5 and 6.5) of growing media. Acidity stress at any level reduced biomass, water, and chlorophyll contents in all the varieties; whereas BARI Wheat-26 showed the least damage. $H^+$ rhizotoxicity also caused oxidative stress through excess production of reactive oxygen species and methylglyoxal which increase lipid peroxidation in all the varieties but the lowest oxidative damage was observed in BARI Wheat-26 due to better performance of the antioxidant defense and glyoxalase systems. Considering the growth, physiological and biochemical attributes BARI Wheat-26 may be considered as acidity stress tolerant, among the variety examined.

• 인터넷정보학회논문지
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• 제15권1호
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• pp.13-27
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• 2014

Agile 방법론은 시간적 제약하에서도 효율적인 개발 프로세스로 빠르게 제품을 완성할 수 있는 방법으로 알려져 있다. 하지만 scrum, XP, DSDM 등과 같은 여타 Agile 방법들처럼 기능주도개발 (FDD) Agile 방법도 보안요소의 불가용성으로 인해 비판을 받고 있다. 이러한 이슈를 보다 자세히 살펴보기 위해 본 연구는 2001년부터 2012년사이에 나타난 연구들에 대한 체계적인 문헌연구를 수행하였다. 본 연구 결과, 현재 FDD 방법은 안전한 소프트웨어 개발을 부분적으로 지원하고 있는 것으로 나타났다. 하지만 안전한 소프트웨어 사용에 관한 상세한 정보가 문헌에 거의 나타나고 있지 않은 것으로 보아 이 분야에 대한 연구 노력은 거의 없어 보인다. 따라서 현재의 5단계 FDD 방법은 안전한 소프트웨어 개발에 충분하지 않음을 알 수 있고 결국, 본 연구는 FDD 방법에서 보안에 기반을 둔 새로운 수행 단계와 프랙티스가 제안될 필요가 있음을 보여준다.

• 한국수소및신에너지학회논문집
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• 제22권4호
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• pp.451-457
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• 2011

Purple non-sulfur (PNS) bacterium $Rhodobacter$ $sphaeroides$ KD131 was studied with the aim of achieving maximum hydrogen production using various carbon and nitrogen sources at different pH conditions. Cells grew well and produced hydrogen using $(NH_4){_2}SO_4$ or glutamate as a nitrogen source in combination with a carbon substrate, succinate or malate. During 48h of photo-heterotrophic fermentation under 110$W/m^2$ illumination using a halogen lamp at $30^{\circ}C$, 67% of 30mM succinate added was degraded and the hydrogen yield was estimated as 3.29mol $H^2$/mol-succinate. However, less than 30% of formate was consumed and hydrogen was not produced due to a lack of genes coding for the formate-hydrogen lyase complex of strain KD131. Initial cell concentrations of more than 0.6g dry cell weight/L-culture broth were not favorable for hydrogen evolution by cell aggregation, thus leading to substrate and light unavailability. In a modified Sistrom's medium containing 30mM succinate with a carbon to nitrogen ratio of 12.85 (w/w), glutamate produced 1.40-fold more hydrogen compared to ammonium sulfate during the first 48h. However, ammonium sulfate was 1.78-fold more effective for extended cultivation of 96h. An initial pH range from 6.0 to 9.0 influenced cell growth and hydrogen production, and maintenance of pH 7.5 during photofermentation led to the increased hydrogen yield.

• 정보처리학회논문지C
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• 제10C권1호
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• pp.61-70
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• 2003

I-Business의 고객과 서비스 제공자들은 사업을 성공으로 이끄는 최선의 방법으로 SLA(Service Level Agreement)를 제공해야 하며, SLA에 포함되어야할 기술적 파라미터로 서비스 가용성을 최우선으로 선정하였다. 이러한 결과들은 웹을 기반으로 한 서비스 제공자들에게 웹 서비스 가용성의 관리가 매우 중요함을 말해준다. 응용서비스 가용성은 사용자의 기대 성능을 유지하면서 제공되는 서비스의 비율로 정의된다. 하지만, 현재까지 웹 서비스 가용성을 측정하는 도구는 단순하게 웹 서비스의 중단 여부만을 판단하기 때문에 사용자의 기대 성능에 대한 요구를 반영하지 못하고 있다. 본 논문에서는 응답시간에 기반한 웹 서비스의 성능저하의 경우를 고려하여 가용성을 측정하고, 불가용을 초래하는 요소가 무엇이며, 그 원인이 무엇인지 밝혀내는 방안을 제시한다. 연구의 결과로 측정도구 WebSerAvail를 개발하였다.