• Tunnel and Underground Space
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• v.27 no.3
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• pp.172-184
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• 2017

The hardness and mechanical properties of the minerals in the Daejeon granite according to depths were investigated by indentation test, load-unload test, and cycle test of dynamic ultra-micro hardness. As a result of the tests, it was possible to classify into three mineral groups (Group-1, -2, -3). The Martens hardness was not significantly different between 41 m and 223 m depths in three mode tests. Nevertheless, they showed in the order of a cycle test < load-unload test < indentation test. Considering the average Martens hardness, elastic modulus, and indentation work for each mineral group, their boundaries were relatively clear. In conclusion, A relatively accurate hardness of minerals can be obtained by three mode tests of dynamic ultra-micro hardness. In addtion, it was possible to characterize the elastic modulus and the elastic-plastic properties of the minerals from the load-unload and cycle tests.

• 동위원소뉴스
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• no.5 s.5
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• pp.1-2
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• 1997

이달 2일 한국원자력안전기술원 시험관리실은 "제47회 RI취급자일반면허시험"의 합격자 125명을 발표하였다.(12쪽 참조) 이번 시험에 총 1,843명 응시에 125명이 합격함으로 합격률은 6.78%로 '96년 306명에 비해 합격률이 저조하며 작년부터 시행된 실무교육에 대하여 설명하고자 한다.

• Korean Journal of Veterinary Service
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• v.44 no.4
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• pp.217-225
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• 2021

We investigated the effect of temperature and stock density on the collection efficiency of oral fluid in the pig farm in Korea. Three pig farms with similar breeding environmental conditions were selected and four pens of each farm (total 12 pens) were tested for the collection efficiency of oral fluid from pigs. Collection rate was considered as significant when oral fluid was collected from 70% of pigs within a pen. In the case of growing pigs, when internal temperature of pig barn increased by one designated degree (5℃), the oral fluid collection rate significantly decreased by 24.7% (P<0.05). The collection rate of oral fluid also decreased by 7.1% (P<0.05) as the density rate increase by one designated degree (12.5%). It was estimated that the collection efficiency of oral fluid decreased when the internal temperature of pig barn was 30℃ or higher, or barn density is higher 25% or high. On the other hand, in the case of stall-housing sows, unlike growing pigs, there was no significant differences according to the temperature, so oral fluid collection was considered to be efficient even in hot season.

• 방재와보험
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• s.32
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• pp.28-28
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• 1987

• 방재와보험
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• s.32
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• pp.29-29
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• 1987

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.6
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• pp.340-344
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• 2005

Salinity problems are caused from the accumulation of soluble salts in the root zone. These excess salts reduce plant growth and vigor by altering water uptake and causing ion-specific toxicities or imbalances. In this investigation, green pepper cultivation technique using mixture bed of soil and rice hull and surface drop fertigation system was examined to prolong the productivity of salt-affected plastic film house soils. Green pepper growth was better in the mixture bed of soil and rice hull comparing to the conventional soil cultivation. Especially root growth was much better and the root had more thin root system in the mixture bed of soil and rice hull. The better growth of root may be due to the better physical conditions and lower EC in the mixture bed of soil and rice hull where nutrient supply was well-managed with fertigation system. In the cultivation with mixture bed of soil and rice hull, fruit yield of green pepper was significantly higher; increased by 43% in comparison to the conventional soil cultivation. Pepper cultivation technique using mixture bed of soil and rice hull and surface drop fertigation system is expected to be a useful method for maintaining and prolonging the productivity of salt-affected plastic film house soils.

• Information and Communications Magazine
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• v.33 no.12
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• pp.22-27
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• 2016

OCF(Open Connectivity Foundation)는 각국의 전문가들이 모여 다양한 사물인터넷 기기들의 상호운용성을 보장하기 위해 표준을 제정하는 민간 표준화 단체로, 인텔, IBM, 마이크로소프트, 삼성전자, TTA 등의 글로벌 기업이 참여하고 있다. 이 표준화 단체에서는 사물인터넷을 위한 플랫폼 표준을 개발하고 있고, 시험기준, 시험방법 등에 대한 시험표준도 제정하고 있다. OCF 시험소에서는 해당 표준에 따라 시험을 수행하고 인증을 통과한 기기에 대해 OCF인증을 부여할 예정으로, 올해 10월 TTA가 시험소로 지정받았다. 본 고에서는 일반적으로 사용되는 통신 기기에 대한 표준 적합성 시험 및 상호운용성 시험 방법을 설명하고, OCF에서 개발된 표준 적합성 시험항목과 시험방법을 소개한다. 마지막으로, 국제적으로 통용되는 OCF 시험 및 인증 체계를 소개하고자 한다.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.4
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• pp.403-408
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• 2014

Lots of electric power has been wasted through the load bank usually in the container boxes during the generator load test of the ship and offshore plant in the new ship building. Therefore in this research, the quantity of wasted electric power through generator load test under construction was investigated on big shipbuilding yard and quantity of electric power that can be recovered is analyzed when produced electric power during the generator load test is connected to KEPCO Grid, according to laboratory's experiment result where recovers electric power produced from small generator connected to KEPCO Grid.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1324-1325
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• 2008

근래 선진 중전기 메이커에서는 차단기, GIS 등의 전통적인 단품 위주에서 탈피하여 전력 IT 기술을 접목한 전력기기/변전소 자동화를 강력하게 추진하고 있다. 특히 전체 변전소를 감시, 제어, 계측, 보호할 수 있도록 전력 IT 기술을 기반으로 한 IEC 61850 적용 변전소 종합 자동화 시스템 개발에 역량을 집중하고 있다. 본 논문에서는 당사에서 개발한 최신 IT 기술을 적용한 IEC 61850 기반 170㎸ GIS용 Bay Controller 관련 구성, 기능, 성능시험 결과에 대해 기술하며, 변전소 내 노이즈로 인해 유발될 수 있는 전자장치 오동작 등을 보증하기 위해 실시한 전자파 장해시험 결과와 GIS와 동일한 환경에 설치되므로 온/습도, 진동/충격시험을 관련 국제규격인 IEC 60255-6, IEC 60255-21-1, 2, 3에 의거하여 실시한 내용을 기술하도록 한다.

• Korean Journal of Veterinary Service
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• v.44 no.1
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• pp.11-14
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• 2021

Seroprevalence of Coxiella burnetii in cattle and goats from southern region of Korea was analyzed. From January to December 2020, 1,409 samples of bulk-tank milk, cattle serum and goat serum were collected and analyzed using ELISA. The prevalence of antibodies in collected was 72.6% (501/682), 4.1% (21/515) and 10.4% (22/212). By age, the seroprevalence of cattle was 2.4%, 4.1%, 5.3% (<2 years, 2~5 years, ≥6 years). In bulk-tank milk of dairy cattle according to region was Gyeongnam 45.5%, Gyeongbuk 77.5%, Daegu 70.0%, Jeonnam 50.0% and Chungbuk 50.0%. And seroprevalence of goats was 10.4% (22/212).