• Journal of the Korean Chemical Society
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• v.50 no.6
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• pp.506-514
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• 2006

purpose of this work was to study the applied effects of out-of-class Chemical Experience Learning (CEL) Programs on scientific process skills and science-related attitude for middle school students. The out-of-class CEL Programs which were developed to make the funny out-of-class chemistry and the exciting science class', included the nature-friendly chemical experiments suitable for natural environment and composed of real life-centered experiences. The out-of-class CEL programs were applied to natural environment through all-day improvement activity. The science club students in D middle school in Busan were selected as the objects of the study consisting of one experiment group and one control group. The out-of-class CEL programs were applied to the experiment group and traditional class method was applied to the control group. The change of scientific process skills and science-related attitudes between two groups were compared and analyzed. And students reaction on the out-of-class CEL programs was investigated. As a result, out-of-class nature-friendly chemical experiments were improved scientific process skills and science-related attitudes of middle school students. Also, more than 70% of students in the experimental group gave positive feedbacks to the out-of-class CEL programs and increased attention, interest, and degree of self-participation in science.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.241-244
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• 2003

유류오염 토양내 유류의 분해와 무기오염물질의 함량과의 관계성을 알아보기위해 부산 문헌지구의 유류 오염 토양 profile중 유류가 비교적 많은 두 층과 유기물이 다량 함유된 제주도 토양을 경유로 오염시킨 토양을 선택하여 유류가 분해 정도와 Pb, Zn, Cd, Ni의 함량을 측정 비교하였다. 토양 채취후 즉시 유류를 추출한 것, 15일간 별도의 미생물 영양원을 가하지 않고 습도와 통풍만을 행하여 토양내 존재하는 미생물들에 의하여만 유류가 분해되도록 한 것, $105^{\circ}C$에서 24시간 열처리를 행하여 미생물에 의한 분해보다는 물리적인 방법으로 비교적 강하게 처리한 것 세가지 경우에서 토양에서 추출한 유류를 분석한 결과 normal alkane이 서서히 상당량 분해되는 양상을 보여주었다. 토양내 Pb, Zn, Cd, Ni를 분석한 결과 부산 시료의 경우 두 층(B2, B3)모두 Cd은 검출한계 이하로, Ni의 경우 극소량의 함량을 보여주었다. Zn의 경우 B2는 28～29ug/g, B3는 12～14ug/g으로 세가지 경우 별 차이 없는 양상을 보여 주었다. 하지만, Pb의 경우 B2에서는 그 함량이 유류의 normal alkane의 분해와 함께 서서히 증가하는 경향을 확연히 보여주었으며, B3의 경우도 B2와 유사한 변화 양상을 보여주었다. 제주도 토양의 경우 Pb는 검출되지 않았고, Zn은 소량 검출되었다. Ba, Ni 함량은 normal alkane 분해에 따라 다소 증가하였다. 따라서, 본 예비실험을 통하여 유류오염 토양에서 유류의 분해와 일부 무기이온사이에는 관련성을 갖고 있으며, 이는 유류 분해정도를 파악하는 지시자로써 특정 무기 오염물질을 이용할 수 있을 가능성이 있으므로 좀더 이들 관계성에 대한 연구가 진행될 필요성이 있다고 판단된다.고 과학적으로 분석할 수 있는 방법이 될 수 있을 것으로 기대된다. 의미를 되새기는 것으로 짧은 연구를 시작하겠다. 등은 활성 값이 70% 이상으로 퇴적물 독성이 상대적으로 낮았다. 이중나선 DNA 함량은 28.4 % - 49%로 대조군에 비해서 감소가 크다. 대부분의 정점이 대조군의 30% 내외로 정점 간의 차이는 크지는 않다. 그러나 다른 측정자료와 같이 정점 22에서 18%로 최소치를 나타내고, 정점 2, 12에서 20% 내외의 값을 보인다. 종합적으로 볼 때 오염물질의 유입이 크고, 광양제철 인근 정점 들이 모두 다른 정점에 비해서 낮아서, 퇴적물 독성이 높은 정점으로 조사되었다.hiwo의 광합성 능력은 낮은 농도들에서는 대조구와 유사하였으나, 5 $\mu\textrm{g}$/l의 높은 농도에서는 초기에 매우 낮은 광합성 능력을 보이다가 시간이 경과하면서 대조군보다 더 높은 경향을 나타냈다. 이러한 결과는 식물플랑크톤이 benso[a]pyrene의 낮은 농도에서 노출될 때는 이 물질을 탄소원으로 사용할 가능성이 있음을 시사한다. 본 연구의 결과들은 연안해역에 benso[a]pyrene과 같은 지속성 유기오염물질이 유입되었을 때 내정여부에 따라 식물플랑크톤 군집내 종 천이와 일차생산력에 크게 영향을 미칠 수 있음을 시사한다.TEX>5.2개)였으며, 등급별 회수율은 각각 GI(8.5%), GII(13.4%), GIII(43.9%), GIV(34.2%)로 나타났다.ments of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japan

• Journal of Aquaculture
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• v.11 no.3
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• pp.353-361
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• 1998

Genetic analysis of body pigmentation pattern has been conducted by the reciprocal monohybrid and back crosses using the wild type zebrafish, Danio rerio, and its aquarium morphs (mutants), leopard danio. Also, the effect fo pigmentation mutation was investigated with regard to the survival rates of eggs and larvae for the first 15 days after fertilization. As a result, the pattern pigment distribution was inherited by a single gene having two alleles, and which was basically followed by the principle of dominace and segregaion in Mendelian inheritance. A locus for pigment pattern turned out to be located on an autosomal chromosome. Average survival rates estimated from the various crosses between, and within, wild type zebrafish and leopard danio were as follows ; they were 80.6${\pm}$4.8% from the crosses within leopard danios ($L{\times}L$), 70.6${\pm}$4.2% between leopard female and wild type male ($L{\times}Z$), 73.2${\pm}$2.0% between wild type female and leopard male ($Z{\times}L$), and 83.8${\pm}$6.7% within wild type zebrafish ($Z{\times}Z$). These results indicated that the leopard danio, which were reported as an "aquarium morph" several decades ago and also known as a mutant in pigmentation pattern of the wild type zebrafish, seemed to be genetically stable like the wild type of zebrafish.zebrafish.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.761-766
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• 2015

This study investigated the effect of protease on quality characteristics of sponge cake. Protease was used at levels of 0.0005 U (PC-1), 0.0010 U (PC-2), 0.0015 U (PC-3), and 0.0020 U (PC-4) for sponge cake preparation. Amylogram showed the setback was significantly decreased in comparison with the control (P<0.05). Height and baking loss rate of control sponge cake were $4.24{\pm}0.18cm$ and $12.01{\pm}0.29%$, respectively. PC-3 and PC-4 showed increased heights of $5.22{\pm}0.16$ and $5.24{\pm}0.11cm$ as well as slightly increased baking loss rates of $12.71{\pm}0.31%$ and $12.89{\pm}0.61%$, respectively. Specific volume and color difference measurements of control showed a specific volume of $3.53{\pm}0.06mL/g$, crust color difference of $53.05{\pm}0.28$, and crumb color difference of $29.84{\pm}0.52$. Measurements of specific volume, crust color, and crumb color of PC-3 and PC-4 were $4.18{\pm}0.02mL/g$, $56.19{\pm}0.84$, $29.05{\pm}0.43$, $4.21{\pm}0.02mL/g$, $56.85{\pm}0.43$, and $29.45{\pm}0.47$, respectively. Firmness measurements showed that the control had the highest firmness. PC-3 and PC-4 were effective at improving the shelf-life of sponge cake as indicated by reduced firmness. Sensory evaluation results demonstrated that all samples scored higher than the control. Throughout the results, the addition of protease increased volume and improved quality characteristics of sponge cake.

• Radiation Oncology Journal
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• v.15 no.2
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• pp.153-158
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• 1997

Purpose : The Dual-Energy Quantitative Computed Tomography(DEQCT) was compared with bone equivalent $K_2HPO_4$ standard solution and ash weight of animal cadaveric trabecular bone in the measurement of bone mineral contents(BMC). Method and Materials : The attenuation coefficient of tissues highly depends on the radiation energy density and effective atomic number of composition, The bone mineral content of DEQCT in this experiments was determined from empirical constants and mass attenuation coefficients of bone,fat and soft tissue equivalent solution in two photon spectra. In this experiments, the BMC of DEQCT with 80 and $120kV_p$ X rays was compared to ash weight of animal trabecular bone. Results : We obtained the mass attenuation coefficient of 0.2409 0.5608 and 0.2206 in $80kV_p$, and 0.2046, 0.3273 and $0.1971cm^2/g$ in $120kV_p$ X-ray spectra for water bone and fat equivalent materials, respectively. The BMC with DEQCT was acomplished with empirical constants $K_1=0.3232,\;K_2$=0.2450 and mass attenuation coefficients has very closed to ash weight of animal trabecular bone The BMC of empirical DEQCT and that of manufacturing DEQCT were correlated with ash weight as a correlation r= 0.998 and r= 0.996, respectively. Conclusion : The BMC of empirical DEQCT using the experimental mass attenuation coefficients and that of manufacture have showed very close to ash weight of animal trabecular bone.

• Journal of Mushroom
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• v.13 no.4
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• pp.314-318
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• 2015

This study was carried out to investigated the avaiability of dried Koojongsi persimmon peels (KPP) as a useful mushroom medium using Pleurotus eryngii ASI 2312. Mushroom cultivation medium used in this study was mixed with medium mixture, corn cob and sawdust (220:65:15, v/v). Dried KPP was replaced mushroom cultivation medium (control) with 5, 10, 15, 20, 30, 40, 50% dried KPP. The T-N content of dried KPP treatments decreased to increase replaced ratio of the dried KPP and C/N ratio was increased to increase replaced ratio of the dried KPP. But T-C content of dried KPP treatments was similar to untreated control. The average cultivating periods of mycelium on dried KPP treatments was delayed to increase replaced ratio of the dried KPP and cultivating periods was delayed over 30% dried KPP treatments. The length of stipe of dried KPP treatments was longer than that of the untreated control to increase replaced ratio of the dried KPP and thickness of stipes was tend to be thinner than that of the untreated control to increase replaced ratio of the dried KPP. The moisture, carbohydrate, crude protein and crude ash content of mycelial were similar to untreated control, but crude fatty acid was increased to increase replaced ratio of the dried KPP. The ${\beta}-glucan$ content of 10% and 15% treatments were higher than untreatment control. The results based on cultivation yield and ${\beta}-glucan$ content indicated that optimal mixture ratio dried KPP was 15%.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1992.10a
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• pp.113-116
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• 1992

소음의 발생 원인은 공기역학적 측면과 구조적 측면으로 나누어지는데, 실제 로는 유동장에서 발생되는 음원과 구조물에서 발생되는 진동과의 상호 간섭 에 의해 보다 복잡한 형태로 발생된다. 음장 문제를 두가지 범주로 구분하면 첫째는 음원과 구조물과의 상호교란에 의한 산란문제(Scattering)와 둘째로 구조물의 자체 진동에 의한 음의 전파현상과 구조물내부에 회전체와 같은 음원이 존재하는 경우에 음의 전파를 관측하는 방사문제(Radiation)가 있다. 실제로 산업용 터빈이나 비행기 엔진 흡입구에서 발생되는 소음, 또는 자동 차의 배기구를 통해 발생되는 소음 그리고 엔진의 진동에 의한 구조적 소음, 기타 가전제품의 회전체(Fan & Motor)에 의한 소음은 방사(Radiation)의 문 제로서 중요 관심 과제이다 수치적 기법으로 근래에 많이 사용하는 방법으 로 BEM(경계요소법), FEM(유한요소법), FDM(유한차분법)이 있는데 본 연 구에서는 유한요소법을 이용하기로 한다. 지금까지는 주로 BEM을 통해서 Far-Field의 음향장을 해석하였지만 복잡한 형상을 갖는 구조물내부에서의 음향장 변화나 구조물 내부에 음원이 존재하는 경우 또는 구조물 자체가 갖 는 물리적 특성치 변화 즉 물체표면에서의 부분 진동문제의 음향장 해석에 있어서 가장 잘 대체해 나갈 수 있는 방법이 유한 요소법이라고 여겨진다. 본 연구에서는 2차원 또는 기하학적으로 축대칭인 3차원 Duct내부에 음원이 존재하는 경우 음원전파에 따른 Near-field와 far-field에서 음의 방향성을 예측하기 위해 먼저 기본적인 유한요소법에 의한 Robin 경계조건을 사용하 여 계산된 결과와 Infinite Element를 도입하여 계산할 결과를 비교하여, Infinite Element가 보다 효율적이며 타당한 결과를 얻음을 확인해 보기로 한다.다 복합적인 측면에서 치료에 임하여야 할 것으로 사료된다. with such configuration.trap with 2.88[eV] deep of injected space charge from the chathode in the crystaline regions. The origin of ${\alpha}$$_2$ peak was regarded as the detrapping process of ions trapped with 0.9[eV] deep originated from impurity-ion remained in the specimen during production process of the material, in the crystalline regions. The origin of ${\beta}$ peak was concluded to be due to the depolarization process of "C=0"dipole with the activation energy of 0.75[eV] in the amorphous regions. The origin of ${\gamma}$ peak was responsible to the process combined with the depolarization of "CH$_3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과 0.05 - 0.10 mm/hr 의 범위로서 이로 인한 강우손실량은 큰 의미가 없음을 알았다.재발이 나타난 3례의 환자

• Journal of Environmental Impact Assessment
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• v.26 no.6
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• pp.479-494
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• 2017

After Fukushima incident, negative sentiment towards nuclear power has led to transition in policies that reduce the dependency on nuclear power in some countries. President Moon of Republic of Korea also announced a national plan of decommissioning retired nuclear power plants stage by stage. Therefore, nuclear power that once was considered the critical solution to energy security and climate change is now a limited option. This study aims to find an optimal energy mix in Korea's electricity system from 2016 through 2030 to combat climate change through energy transition with minimum cost. The study is divided into two different scenarios; energy transition and nuclear sustenance, to compare the total costs of the systems. Both scenarios show that electricity generated by wind technology increases from 2018 whereas that of photovoltaic(PV) increases from 2021. However, the total cost of the energy transition scenario was USD 4.7 billion more expensive than the nuclear sustenance scenario.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.1
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• pp.1-9
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• 1999

To find pertinent soil type and maintenance method for artificial planting ground, the effects of soil compositions{sandy loam(S), vermiculite(V), sandy loam+vermiculite+sand(SVS), sandy loam+ carbonized rice husk+sand(SCS), sandy loam+humus sawdust+sand(SHS)}, and fertilizers (organic, chemical) on plant(kentuckyblue grass) growth were measured and compared from the field experiment. The results are summarized as follows 1. the highest germination rate is found from "vermiculite(V)" and the lowest from "sandy loam(S)" among tested 5 soil compositions. 2. "sandy loam+vermiculite+sand(SVS)" composition shows the highest plant height growth effect (5cm growth during tested 3 months) comparing to other 4 compositions. 3. "sandy loam+vermiculite+sand(SYS)" composition shows the highest ground covering rate after first two months, but it concede its order to "sandy loam+humus sawdust+sand(SHS)" composition after next one month growing. 4. the effects of fertilizers are follows 1) Among the blocks where no fertilizer was tried, the predominant height growth was obvious in "sandy loam+carbonized rice husk+sand(SCS)" and "sandy loam+humus sawdust+sand(SHS)" composition. 2) Among the blocks where chemical fertilizer was tried, relatively positive results were found from "vermiculite(V)" and "sandy loam+vermiculite+sand(SYS)" blocks on germination and growth rate. But on the ground coverage ratio, the effect of "sandy loam+carbonized rice husk+sand(SCS)" composite precede that of those 2 composites. 3) Among the blocks where organic fertilizer was tried, "sandy loam+humus sawdust+sand(SHS)" and "vermiculite(V)" blocks show relatively high ground coverage rate, growth rate than others. 4) When compositional differences were not considered, the block where organic fertilizer was tried shows most positive effects on all 3 measurements-germination ratio, height growth and ground covering.

• Applied Biological Chemistry
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• v.46 no.1
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• pp.7-11
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• 2003

Cloning and expression of copper-binding peptide gene in E. coli was carried out to enhance the copper-chelation capacity. E. coli was transformed with pET vector containing the copper-binding region of potato polyphenol oxidase gene and polyhistidine-coding DNA, and the copper content of E. coli harboring each vector was measured. No increase in intracellular copper was observed in E. coli harboring PPOCBpET32 vector, which contains DNA for polyphenol oxidase copper-binding region. Intracellular copper content of E. coli harboring pE728a vector, which contains one hexahistidine unit DNA, was 2,500 ppm after culturing without kanamycin, whereas E. coli harboring pET-his vector, which contains nine hexahistidine unit DNAs was 3,200 ppm.