• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.69-70
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• 2001

음성 통신계를 통해서 전달되는 음성신호 품질의 좋고 나쁨을 수화자의 청각을 거친 반응(주관평가)에 의해 객관적으로 표현한 것을 통화품질이라 한다. 잠수기 어업 등과 같은 수중 활동에 사용할 무선수중전화기 시작품 설계와 최적의 통화품질 평가 방법 선점의 기초 자료로써 레저스포츠등에 인부 사용되고 있는 기존의 무전수중전화기로 수중 음성통신에서의 명료도와 단어 요해도를 측정하였다. (중략)

• The Korean Journal of Zoology
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• v.34 no.3
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• pp.403-409
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• 1991

화학적 암 유발물인 diethylnitrosamine(DENA) 연여로 야기되는 흰쥐 (Sprague Dawley) 간세포의 변화 양상을 전자현미경과 silver염색방법으로 관찰하였다. DENA는 간세포내의 핵, 미토콘드리아, 담즙관에 뚜렷한 형태적 변화를 일으켰으며 인(nucleolus)의 크기와 수도 증가하였다. 또한 정상세포보다 인 (nucleolus) 부위의 염색 정도도 강하였는데 이것은 silver granule이 서로 연결되어 망상구조를 형성하기 때문인 것으로 생각되며 이들 망상구조는 순수한 rDNA부분과 핵내 단백질이 인내에서 서로 엉킨어 나타나는 현상일 것으로 사료된다. 또한 DENA투여 켤과 나타난 인의 크기와 인부위의 수적 증가현상의 결과로 rRNA 합성물의 변화를 유추할 수 있었다.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.358-364
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• 2017

많은 공사 현장에는 개구부, 작업발판, 가설계단의 통로 등에서의 추락사고를 방지하기 위해 설치하는 가시설물 중 안전난간이 있다. 안전난간은 작업장에서 현장인부들의 생명과 직결되므로 반드시 적절한 기준에 맞춰 설계를 하는 것이 필요하다. 이러한 안전난간은 표준안전난간으로서 추락재해방지 표준안전작업지침[1]에 의해 설계 기준이 명확하게 명시되어 있으며 난간대와 기둥각 부분 접합부는 쉽게 변형, 변위를 일으키지 않는 구조를 가져야 한다. 본 연구에서는 지침에 지시된 표준안전난간을 실제 설계기준에 맞게 직접 구조물을 모델링하고 EDISON용 구조해석 프로그램인 CASADsovler를 통해 유한 요소 해석을 수행하여 안전난간에 가해지는 응력 및 변위 결과들을 통해 구조의 안정성을 시험해 보았다. 더하여 다구찌 기법과 최적설계에 기반하여 안전난간 무게의 경량 최적화를 위한 연구를 진행하였다.

• Proceedings of the KAIS Fall Conference
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• 2000.10a
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• pp.140-144
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• 2000

실리콘 웨이퍼 생산의 여러 단계의 공정 중 평탄도를 측정하고 제어하는 polishing 공정은 평탄한 정도에 의하여 제품의 합격 여부가 결정되는 측면에서 매우 중요한 과정이다. 이 연구에서는 polishing 공정의 자동화를 모색해 보기 위해 웨이퍼의 형상을 추정한 데이타를 이용하여 그 형상을 분류하는 알고리즘을 개발하였다 추정된 웨이퍼의 모양에 따라 9개의 카테고리로 분류하고, 각 카테고리를 세 종류의 통계값을 이용하여 세부 분류한다. 개발한 알고리즘을 구현하여 웨이퍼의 형상을 분류하는 모듈을 개발하였다. 개발한 알고리즘을 검증하기 위해 여러 웨이퍼를 대상으로 실험을 수행하였다. 대부분의 웨이퍼를 정확하게 잘 분류하고 있으나 인부의 미세한 변화를 감지하지 못함으로 인하여 정확하게 분류하기가 어려운 경우를 관찰할 수 있었다. 웨이퍼의 형상을 다양하게 분류함으로써 polishing 공정의 자동화를 좀 더 구체적이고 효율적으로 접근할 수 있는 계기가 됨 깃으로 기대한다.

• 월간 기계설비
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• no.2 s.199
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• pp.52-55
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• 2007

2007년 상반기 적용 건설업 임금실태조사(시중노임단가) 결과가 1월 1일자로 공포되어 적용에 들어갔다. 2006년 하반기 건설업 임금의 일일 평균임금은 9만6,343원에 비해 각각 1.7%, 3.6/% 상승한 것으로 나타났다. 건설 관련 145개 직종 중 104개 일반공사 직종의 평균임금은 전체 직종의 전반기 대비 상승률보다 0.1%포인트 낮은 1.6%였고, 특히 형틀목공, 철근공, 보통 인부 등 주요 15개 직종은 전체 직종 평균치를 웃도는 2.6% 상승함으로써 전체 임금상승을 이끌었다. 대한건설협회는 매년 상·하반기 2차례에 걸쳐 건설업 시중임금을 조사해 발표하고 있으며 이번에 발표한 임금은 전국의 1,700개 건설현장의 건설 관련 145개 직종을 대상으로 2006년 9월 한달간 실제 지급된 임금을 8시간 기준으로 조사한 것이다. 이번 임금 조사결과는 1월 1일부터 8월 30일까지의 건설공사 원가계산에 적용된다. 다음은 설비건설부문과 관련 직종 노임단가 분석 및 개별직종 노임단가 현황이다.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.411-422
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• 2004

A limnological survey was conducted in a reservoir, Lake Hoengsung located in Kangwondo, Korea, from July 2000 to September 2001 on the monthly basis. Phosphorus loading from the watershed was estimated by measuring total phosphorus concentration in the main tributary. Secchi disc transparency, epilimnetic (0-5 m) turbidity, chlorophyll a (Chl-a), total phosphorus (TP), total nitrogen(TN) and silica concentration were in the range of 0.9-3.5 m, 0.1-8.5 NTU, 0.3-32.4 mgChl $m^{-3}$, 5-46 mgP $m^{-3}$, 0.83-3.55 mgN $L^{-1}$ and 0.5-9.6 mgSi $L^{-1}$, respectively. Green algae and cyanobacteria dominated phytoplankton community in warm seasons, from July through October, 2000. In July a green alga (Scenedesmus sp.) was dominant with a maximum cell density of 10,480 cells mL. Cyanobacteria (Microcystics sp.) dominated in August and September with cell density of 3,492 and 295 cells mL ,respectively. Species diversity of phytoplankton was highest (2.22) in July. The trophic state of the reservoir can be classified as eutrophic on the basis of TP, Chl-a, and Secchi disc transparency. Because TP concentration was high in flood period, most of phosphorus loading was concentrated in rainy season. TP loading was calculated by multiplying TP and flow rate. The dam managing company measured inflow rate of the reservoir daily, while TP was measured by weekly surveys. TP of unmeasured days was estimated from the empirical relationship of TP and the flow rate of the main tributary; $TP=5.59Q^{0.45}\;(R^2=0.47)$. Annual TP loading was calculated to be 4.45 tP $yr^{-1}$, and the areal P loading was 0.77 gP $m^{-2}\;yr^{-1}$ which is similar to the critical P loading for eutrophication by Vollenweider's phosphorus model, 0.72 gP $m^{-2}\;yr^{-1}$.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.11-17
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• 1999

This experiment was conducted to select and utilize the tolerant rice varieties for ozone stress through comparing the physiological responses. In SOD activity, Backunchalbyeo which treated once by 0.15 ppm $0_3$, Ilpumbyeo and Inbujinado treated twice showed significantly different SOD activity compared with $non-O_3$ treatment. No significant difference of SOD activity in three-times $0_3$ treated Sangnambatbyeo and Hangangchalbyeo was found as compared to ($non-O_3$ treated)control, POD activity, when Sangnammbatbyeo, Hangsngchalbyeo, Ilpumbyeo and Inbujinado were sequently treated by third ozone, showed no significant difference between $O_3$ treatment and $non-O_3$. In the comparison of amino acid content in rice leaf blade between three times $O_3$ treatment and $non-0_3$ treatment in 3 varieties, phenylalanine content represent as increased quantities. Especially, in three times $0_3$ treatment of Sangnambatbyeo, phenylalanine content(O.66 mg/g) was significantly increased as compared with $non-O_3$. Visual-growing characters of Sangnembatbyeo were significantly different between $0_3$ treatment and non-treatment. However, grain-filling rate showed no difference. SOD and POD related to resistant mechanism were high activity. In addition, phenylalanine known as precursor which is synthesized resistant materials was increased by $0_3$ treatment. These results suggested that Sangnambatbyeo which increased SOD and POD activity, and phenylalanine content under ozone stress could be selected as a tolerant variety.

• Journal of the Korea Institute of Building Construction
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• v.10 no.3
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• pp.121-128
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• 2010

This study aims to make improvements to the standard estimation process used to estimate reasonable costs for construction work, and to suggest a work crew based estimation using a new cost estimation model. In addition, work crew shift combination and construction process were systematically organized in order to improve the estimation technique and the construction capability of the cement liquid waterproofing work for apartment buildings. In addition, in terms of manpower and productivity, analyses were performed on the cement liquid waterproofing work for apartment buildings with net areas between $84-85m^2$ and $125-184m^2$, and the results were then compared with those calculated using the conventional work-crew based estimation method. Through this study, when the results of this study and those calculated by the conventional method were compared, for apartments with the net area of $84-85m^2$, the differences between specialists were shown to be 1.91 times to 2.13 times on average, while they were 8.82 times to 9.52 times between normal workers on average. For apartments with the net area of $125-184m^2$, the differences betweenspecialists were shownto be 1.89 times to 2.07 times on average, and 8.57 times to 9.38 times on average between normal workers.

• Journal of Korean Society of Forest Science
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• v.112 no.2
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• pp.217-229
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• 2023

Forest projects often apply construction industry labor rates, without considering the demanding work conditions and labor intensity unique to forest operations, resulting in workplace issues. This study aims to analyze forest operations' characteristics and wage survey methods in other fields to establish a framework for surveying the wages of forest workers. The developed framework was tested through direct surveys conducted with all forest operation companies. Survey items included actual wages by occupation, identification and removal of outliers using quartile deviation, and occupation-based wage calculation. Results revealed that the appropriate wages for 2022 were as follows: KRW 163,376 for general workers, KRW 221,407 for special workers, KRW 250,045 for work leaders, and KRW 239,863 for wood cutters. These figures were 16.27% higher than those derived from the standard construction wage survey. The developed framework was validated by comparing the appropriate wages with both the standard construction wage survey and the forestry workers' wage. The results indicated that the wages calculated using the developed framework were 4.5% more similar to the forestry workers' wage compared with those from the standard construction wage survey. Consequently, the standard construction wage survey was deemed unsuitable for forest projects. To ensure efficient forest operations, it is imperative to conduct wage surveys using the developed framework over multiple years to accumulate sufficient data.

• Journal of Environmental Impact Assessment
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• v.9 no.4
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• pp.291-300
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• 2000

Juam lake is a major water reservoir for the industrial and agricultural activities as well as the residental life of Kwangju and Chonnam regions. However, the water quality of the lake is getting worse due to a large quantity inflowing to the lake. The excessive growth of algae by the overfertilization may result in water treatment problems and also the interference with desirable water uses of navigation, aesthetics, recreation, and aquatic ecosystem. Thus the purpose of this study is to investigate the species and their amount of planktons in the lake and the relationship between the P loading amount and the chlorophyll-a used as a primary productivity index. The results of the investigation show that (1) the predominant species of algae are Microcystis aeruginosa, Anabaena affinis, Melosira granulata, Synedra acus, and Coelastrum cambricum, (2) the trophic state of the lake can be classified as eutrophic, and (3) there is close relation between the P loading amount and the chlorophyll-a.