• Korean Journal of Environment and Ecology
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• v.15 no.2
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• pp.153-158
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• 2001

영산강 수계의 습지생태계 모니터링의 일환으로 4개 지역을 선정하여 황소개구리 205개체를 채집하여 이들의 외부기형 출현율 및 양상을 조사하고 그들의 체내 조직에 축적된 중금속 농도를 분석하였다. 황소개구리의 기형 출현율은 6.8%로 다른 척추동물에서의 자연발생률 3%보다 높았으며, 기형은 모두 앞 또는 뒷발갉에서 나타났다. 유형별로 보면 결손(Ectrodactyly)이 64.3%로 가장 많았고 다음으로 확장(Dilation)이 28.6%, 절단(Truncation) 7.1%의 순이었다. 정상과 기형 개체간에 중금속의 농도를 조직별로 비교해 본 결과 기형개체의 신장에서 Mn은 4배, Zn 은 1.5배, Cu은 7배, Pb는 8배, Cd는 7배 정도 높았다. 또한 기형 개체에서는 이들 원소의 조직분포 패턴도 변화한 것으로 나타났다. 이러한 결과들로부터 황소개구리는 습지생태계의 모니터링 시료로서 유용하게 이용될 수 있음을 알 수 있었다.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.167-170
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• 2002

We have proposed new pixel structures for Active Matrix OELD (AMOELD) to improve the uniformity of luminance and manufactured a full-color 3.6-inch QVGA AMOELD. The proposed pixel structures, composed of four TFTs and one capacitor, can display 64 gray scales by compensating threshold voltage (Vth) variation of driving TFTs. Nonuniformity and peak intensity of measured luminance are under 14% and over $200cd/m^2$, respectively.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.402-406
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• 2006

The physical and chemical characteristics of ALC were analyzed and showed 2.2 of specific gravity and 9.05 of pH. The results of leaching tests with standard method for soil and waste indicated heavy metals(Cu, Cd, Pb, $Cr^{6+}$) were under maximum concentration level. The anaerobic digestion sludge was attached in the surface of ALC within 90 hours. As the results of batch test, pH of the ALC and Bio-ALC were decreased from initial pH of ALC to 8.7 and 7.8 respectively Also, the concentration of heavy metals was rapidly eliminated in the solution with the batch test. The result of column experiment indicates that the removal efficiency of ALC was showed 66% of T-P, 60% of T-N, and 67% of CODcr. Also, removal efficiency of Bio-ALC was slightly higher than that of ALC in T-N (64%) and CODcr (74%).

• The Korean Journal of Zoology
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• v.34 no.1
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• pp.103-109
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• 1991

한국 특산종 Cobitis longicorpus (왕종개)의 주요 분류형질인 골절반의 지리적 변이를 조사하기 위하여 남한의 12개집단 205개체를 이용, 골질반의 type분석과 계수학분석을 실시하였다. Type분석 결과, 동해유입하천집단(영덕의 송천, 축산천, 경주 형산강, 울주 회야강)의 골질반은 등근 삼각형, 삼각형, 인각형으로 남해 유입하천 및 도서집단의 타원형, 반타원형, 부채꼴과 구별되었다. 골질반의 계수화분석 결과에서도 동해유입하천의 골질반 폭은 비교적 좁아 남해유입하천 및 도서지방과의 평균 CD값이 1.64로 새종 수준 이상의 차이를 보였다. 아울러 조사, 비교된 제 1 체측반문도 동해유입하천에서는 C. longicorpus의 특징이 전혀 나타나지 않아, 원기재질단인 섬진강집단을 포함한 남해유입하천 및 도서집단과 구별된 새종수준의 종분화가 이루어진 것으로 사료되었다.

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.62-64
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• 1964

The cation exchange chromatographic studies for the analysis of transition metals have been described. The quantitative separation of a mixture of Fe(Ⅲ), Cu(II), Zn(II), Ni(II), Cd(II), Co(II) and Mn(II) has been obtained by elution, through a 28cm column of the resin, Dowex 50 ${\times}$ 4 (100∼200 mesh), using 0.45 M $NaNO_3$+0.05 M Na-tartrate solution as eluent, starting with the eluent of pH 3.5, followed stepwise by pH 4.0 and 4.5. A comparison between the calculated and the observed peak positions in the elution curve has been shown. The relative stability constants for tartrate complexes of some transition metals have been calculated by using distribution ratios obtained in this separation procedure.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.758-761
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• 2000

This study was performed to investigate the contamination levels of harmful heavy metals that sampled from June. 1 to June. 31, 1999, at 3 areas in Jeonbuk west cost area. The heavy metal contents were determinated by ICPS (Inductively Coupled Plasma Spectrometer) method. The levels of total lead, cadmium, aluminum, zinc and copper were determined and the results were summarized as follows: The minimum and maximum values (ppm) of 3 areas of shellfishes (shortneck clam, hard clam, cockle clam, snail and top sell) were Pb: 1.29~4.35, Cd:0.12~0.37, Al: 9.45~54.06, Zn: 9.65~15.14, Cu: 0.62~1.64 ppm.

• Korean Journal of Optics and Photonics
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• v.14 no.1
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• pp.58-64
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• 2003

In order to read correct data from a disk-type holographic storage medium, it is very important to implement a servo-control in the pick-up module, as in a conventional CD-ROM. We propose a novel servo-control method using a glass plate on the optical axis, which is able to compensate the mechanical errors coming from wobbling of holographic disk and spindle motor. By rotating the glass plate within $\pm$10 degrees, we can reduce the reading errors of $\pm$200 ${\mu}{\textrm}{m}$ to $\pm$15 ${\mu}{\textrm}{m}$.

• Explosives and Blasting
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• v.23 no.1
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• pp.55-64
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• 2005

Safe and cheap emulsion explosives have recently replaced the existing CD explosives in order for people to reduce the prime cost and to prevent the safety accidents from happening in construction and civil engineering sites. However, the emulsion explosives have been in reality fared with difficulties in terms of the blasting force when using them in the tunnel constructed in the rock mass composed of hard rock. In this regards, this study is to verify their blasting efficiency and possibility of construction by applying MegaMEX, one of the high performance Emulsion explosives, to the rock mass of hard rock. In terms of their blasting efficiency such as advance ratio and fragmentation, it has turned out that they have overcome the limit of the existing Emulsion explosives and they have had the equivalent level of MegaMITE, one of the GD(Gelatin dynamite) types of explosives while they have been also advantageous to the environmental aspects.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.19-35
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• 2003

In order 새 investigate the spatial and seasonal variations of heavy metal pollution in heavily industrialized urban area, urban roadside sediments were collected for five years from gully pots in Seoul City. A series of studies have been carried out concerning the physicochemical characteristics of the sediments in order to evaluate the contamination of heavy metals such as Cd, Co, Cr, Cu, Ni, Pb and Zn. Roadside sediments and uncontaminated stream sediments were analyzed for total metal concentrations using acid extraction. The roadside sediments are characterized by very high concentrations of Zn (2,665.0$\pm$1,815.0 $\mu\textrm{g}$/g), Cu (445.6$\pm$708.0 $\mu\textrm{g}$/g), Pb (214.3$\pm$147.9 $\mu\textrm{g}$/g) and Cr (182.1$\pm$268.8 $\mu\textrm{g}$/g), indicating an artificial accumulation of these metals to the sediment chemistry. Comparing with average contents of uncontaminated stream sediments, roadside sediments were shown zinc 14 times (up to 64.4), copper 9 times (up to 181.7), lead 6 times (up to 63.7), cobalt 6 times (up to 168.7), nickel 4 times (up to 98.4), cadmium 2 times (up to 12.8) and chrome 2 times (up to 40.2) high content. The relative degree of heavy metal pollution for roadside sediments collected from each district in Seoul City is evaluated using the “geoaccumulation index”. As a result, heavy-metal contamination is highest centering the oldest residential district and industry area, and contamination level decreases as go to outer block of the city. The factor analysis results indicate that the levels of Cu, Ni, Fe and Cr are strongly related to numbers of factories, whereas the concentrations of Cr, Zn and Cd dependant on pollution index, indicating artificial contamination due to site-specific traffic density.

• Journal of the Korean Dietetic Association
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• v.12 no.3
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• pp.243-253
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• 2006

The purpose of this study was to investigate dietitians' needs of teaching materials about nutrition education for school children in Kyonggi and Chungnam(including Daejeon) areas. This study was carried out using questionnaires via e-mail or in class to the subjects of 166 elementary school dietitians as 68 in Kyonggi and 98 in Chungnam. The number of small(less than 700 meals), medium(700-1400 meals) and large(over 1400 meals) schools based on served meals daily were 48, 62 and 56, respectively. The results are as follows: Frequency of nutrition education for students as well as for teachers was samely very low as 'once per two months' and the education used to perform during lunch time mostly. For preparing nutrition education they obtained informations from the internet(64.0%). The main topics of nutrition education they used to covered were 'et's eat breakfast', 'table manners', 'the relations of body and nutrients', 'food waste', 'foods and calorie', etc.. The largest limit of nutrition education practices faced by school dietitians were pointed out as 'lacks of teaching materials' and 'counseling techniques'. Most dietitians wanted CD or substantial teaching materials for the practices, and required their contents covering 'cooking', 'food and calories', 'let’s eat various foods', 'relations of body and nutrients', 'regular meal is important’ and etc.. Since we expect nutrition teachers to be realized soon, nutrition education/counseling is emphasized more as their duty. Even though school dietitians revealed poor self-confidence, they were positive to get improved by reeducation of nutrition counseling methods and skills. If easy and suitable education materials(CD type) are developed as good as the school dietitians desired, the materials could contribute much to better nutrition education/counseling practices at schools.