• Journal of the Korean Chemical Society
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• v.48 no.3
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• pp.283-290
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• 2004

The purpose of this study were to develop of courseware using scaffolding strategy and to investigate the effect of courseware instruction upon students' conceptual understanding and affective domain including effort and self-checking. 10th grade students in the experimental and control groups were selected from high school at Cheongwon-gun in Chungbuk, and taught about chemical reaction rate for 3 class hours. The students in the experimental group studied individually through courseware using scaffolding strategy and worksheet and teacher-centered expository lesson was used in the control group. Prior to the instructions, test specification for problem-solving assessment (TSPSA) was administered and the scores of the previous science achievement test were obtained. After the instructions, the posttest on conceptual understanding and TSPSA were administered. Results of this study revealed that the mean score of the experimental group in the conceptual understanding test was similar to that of the control group at statistically significant level. This result implies that the courseware using scaffolding strategy could be a tool of the individualized instruction. The experimental group improved significantly better in three components of the TSPSA such as effort, self-checking, and cognitive strategy. From this result, it is considered that learners' self regulation is improved by being taken over responsibility of learning. So, it is suggested that instruction using scaffolding strategy is needed in science class to improve self-leading learning ability.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.6
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• pp.15-23
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• 2011

Driving directly in front of the driver of a vehicle driving in front of the vehicle and it is commonly known is affected. Responding to the car in front of the driver and the vehicle in front, and these follow the model is known as Three-Car-Following Model. Platoon vehicles to follow behind the driver's visibility is affected by the a tinted vehicle, and Parameters of the model is estimated to be affected also. In this study, in Three-Car-Followng Model parameters were estimated. and the parameter values differ about whether and how analysis was performed by the level of Visible Light Transmission Percentage. RTK GPS receiving data through field experiment analyzed based on sensitivity of three car by Visible Light Transmission Percentage and ${\gamma}$. And With statistical verification of driving directly in front of the driver in front of the vehicle and that the moving vehicle is influenced also confirmed. Also Visible Light Transmission Percentage is lowered, the vehicle in front of the driver's behavior showed sensitive reactions. In the further need to research for influence analysis of traffic flow capacity by the level of VLT.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.212-217
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• 2003

This study was conducted to search for possible cultivation area of Rhodiola sachalinensis as well as to obtain the basic information of growth characteristics. One­year old nursery plants of Rhodiola sachalinensis were collected from Yonbyeon Hongkyungcheon development society in China This expriment was evaluted in three areas according to sea level such as plain region in Cheongwon(50m at sea level), mid­mountainous region in Jecheon(350m at sea level) mountainous region in Banyans(650m at sea level). The growth status Rhodiola sachalinensis showed wide range of variation in there areas. Plant height showed from 8.1cm to 15.8cm, number of branch showed from 3.1 eachs to 4.6 eachs and rate of withering showed from 76％ to 94％, respectively. It was increased rapidly at the early August caused by summer depression. Flowering period of Rhodiola sachalinensis was shown at around middle and late June, total duration of flowering showed from 12 to 13 days and flower colors were various as brown, dark purple, yellow green and brown red color.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1465-1470
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• 1999

Aroma was extracted from Applemint(Mentha rotundifolia(L.) Huds) with SDE(simultaneous distillation and extraction), SFE(supercritical fluid extraction) and headspace method and the compounds of aroma were tentatively identified with GC-MS. The functionality of aroma compounds were determined with GC-olfactometry. Total 67 compounds were identified. Among them, 39 compounds were determined from SDE, 42 from SFE and 16 from headspace extract. Many terpene compounds were extracted with SDE and headspace methods but hydrocarbones with SFE. The major constituents of aroma obtained from SDE and SFE, were piperitenone oxide, germacrene-D and trans sabinene hydrate, but those from headspace method were 3-octanol, 1,8-cineol, camphene and benzeneacetaldehyde. Results of sniffing test, determining characteristics and strength of aroma showed that the major constituents of SDE extract were refreshing sweet and apple-like(ethyl-2-methyl butanoate), sweet and fruity-like$({\alpha}-thujene)$, fresh mushroom-like(1-octen-3-ol, 3-octanol), and bitter herb-like$({\delta}-cadidene)$. Major constituents of aroma extracts obtained from headspace method were alcoholic, refreshing sweet and apple-like(ethyl 2-methyl butanoate), unpleasant chemical, and bitter herb and grassy-like(camphene).

• The Journal of Engineering Geology
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• v.18 no.4
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• pp.459-470
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• 2008

Types of slope failure related to cut slope stability are interpreted through case analyses, and also factors affecting structurally controlled instability investigated, which are developed by geologic structures along a national road No. 25 across the Cheongwon and Boeun-Guns, Chungbuk. Engineering properties such as orientation, persistence, roughness and uniaxial compressive strength of joints are analyzed by square-inventory method in three areas with well-preserved outcrops. The study area is located in Ogcheon folded bet, and are composed of quartz-schist and quartzite in the Midongsan Formation and phyllite in the Ungyori Formation. Flexural beds by folding, schistosity and cleavage besides joints are developed due to slight metamorphism. Various types of joints developed by folding are formed such as strike-parallel, strike-perpendicular, wedge and wrench joint sets by both initially regional and later superposed folding. Factors of slope instability are created by crossing the orientations of joint, cleavage, bedding and slope one another. In the case that the orientation of a slope is coincident with one of beds, factors causing large-scale failure including plane failure are increased greatly. Also in the region that orientations of the slope and bed are crossed each other at high angle, only local and minor failures are shown in the slope.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.73-81
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• 2009

Population viability analysis of a Gold-spotted pond frog (Rana chosenica) population at Cheongwon-gun, Chungbuk, in South Korea was conducted and we proposed several suggestions for effective conservation and re-introduction of the species. Simulating a developed model over 1,000 times predicted that the population will exist over 30 years with a relatively low growth rate of 0.113, but with a high probability of extinction as 81.1%. Population growth and extinction probability were the most greatly depended on the rate of successful metamorphosis. In the case of outbreak of amphibian diseases such as Chytridiomycosis and Ranavirus, the population will be easily extinct within 4 years with 100% probability. In a habitat of which carrying capacity is 200, to successfully re-introduce an extinct population, it is initially needed to put 100 individuals of which 83% is males and its age structure is normal-distributed. If we additionally conducts artificial supplementation of 10% individuals every 2 years from 4 years to 10 years after initial reintroduction, the population will become a stable with 0.297 growth rate and 0.290 extinction rate. Our results are the first case of amphibian population viability analysis in Korea and could be used to develop effective conservation and re-introduction plans for endangered Gold-spotted pond frog.

• Journal of Applied Biological Chemistry
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• v.55 no.2
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• pp.129-133
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• 2012

To exploit plant growth promoting bacteria in the roots of Miscanthus sacchariflorus, a biomass energy crop, total 64 bacteria were isolated. For the investigation of plant growth promoting effects from the isolated bacteria, production of indole acetic acid (IAA) and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activities were tested and other cultural conditions were examined. As results, 8 isolates showed plant growth promoting effects on the M. sacchariflorus and an isolate designated Agrobacterium sp. BE516 has the highest activity by enhancing the shoot elongation over 2-fold than the control. Agrobacterium sp. BE516 produced 64 ${\mu}g$ IAA per mL and showed ACC deaminase activity which is involved in the resistance to environmental stress such as high salt and drought. It could grow at low temperature in the range from 4 to $15^{\circ}C$, at pH 4.0 and at 4% NaCl. These results indicate that the Agrobacterium sp. BE516 can be useful as a bio-fertilizer for M. sacchariflorus under the stressed conditions.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.60-70
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• 2013

This study aims to develop a truck priority on left-turn algorithm that can reduce greenhouse gas emissions by reducing heavy duty truck's stops at signalized intersection. The signal priority is granted for a left-turn phase, because heavy duty trucks can deteriorate left-turn traffic flow due to the low acceleration or deceleration rate and large turn radius. Truck priority allows to provide the stable speed control for heavy duty truck, and reduces emissions at the signal intersection. Also, two signal recovery strategies are compared for various traffic conditions. This study analyzes the effectiveness of truck priority such as greenhouse gas emissions and fuel consumption reduction, and total travel time saving using the PARAMICS and Comprehensive Modal Emissions Model (CMEM). The results show that signal priority for heavy duty trucks has an effect on reducing greenhouse gas emissions and fuel consumptions at non-peak hour. Also, it shows decreasing total travel time due to reducing truck stops.

• Proceedings of the Mineralogical Society of Korea Conference
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• 2003.05a
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• pp.53-53
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• 2003

남한에 분포하는 현생 화강암류는 트라이아스기-쥬라기의 소위 대보화강암과 백악기-제3기의 불국사화강암으로 분류되어 왔다. 대보조산운동은 대동누층군의 퇴적이후에 일어난 조구조운동을 지칭하므로 트라이아스기의 화강암을 포함하는 대보화강암이라는 명칭은 그와 사실상 직접적인 관계는 없다. 트라이아스기-쥬라기의 화강암은 영덕, 청송 암체 외에는 경상분지 밖에 위치하고 백악기-제3기의 화강암은 속리산, 월악산 암체 외에는 경상분지 안쪽에 주로 분포한다. 트라이아스기-쥬라기의 화강암 중 영광-대전-청주-충주-원주-강릉 방면에 걸쳐 북동-남서 방향으로 분포하는 화강암질 저반은 남한에서 가장 넓은 면적을 차지하는 화강암체지만 신뢰할만한 연대측정 자료가 매우 부족한 실정이다. 이 화강암질 저반에 대해서는 Rb-Sr, K-Ar법이 해답을 주기 어렵다. 예를 들어 청주-음성-증평 지역의 화강암류에 대한 Rb-Sr 전암 자료는 분산이 심하며 약 380 Ma에 해당되는 초시선을 보여 기원물질의 불균질성 내지 불완전한 혼합 효과를 반영하고 있다. 옥천대와 영남육괴에 분포하는 일부 화강암체에 대해 잘못 보고된 Rb-Sr 전암연대 역시 모두 중광물의 U-Pb 연대보다 오래된 값을 보이는 것으로 보아 이들은 생성 당시부터 일정한 $^{87}$ Sr/$^{86}$Sr 초기치를 가지지 않고 Rb/Sr 비에 따른 양(+)의 기울기를 가졌음이 확실하다. 과잉의 방사기원 Ar을 가지거나 폐쇄온도가 낮은 광물들을 대상으로 한 K-Ar 자료 역시 화강암체의 관입편대를 정확하게 지시할 수는 없다. 우리는 이에 대한 연구의 일환으로 충청남도 청원군의 물류센터에서 채취한 중립질의 흑운모화강암 한 시료에 대한 U-Pb 스핀연대측정 결과를 다음과 같이 보고한다. $^{206}$ Pb$^{*}$ /$^{238}$ U age = 174.6$\pm$2.7 Ma $^{207}$ Pb$^{*}$ /$^{235}$ U age = 170.3$\pm$14.6 Ma $^{207}$ Pb$^{*}$ /$^{206}$ Pb sup */ age = 111$\pm$187 Ma 위에서 볼 수 있듯이 청주화강암의 스핀에 대해 콘코던트(concordant)한 연대가 얻어졌으며 자료의 오차, 스핀의 U-Pb계에 대한 폐쇄온도 및 화강암의 솔리더스(solidus)를 고려할 때 $^{206}$ Pb$^{*}$ /$^{238}$ U 연대인 174.6$\pm$2.7 Ma를 관입정치시기로 해석한다. 동일 시료의 흑운모에 대해서는 145 Ma의 Rb-Sr 연대가 얻어졌으며 따라서 관입이후 약 35$0^{\circ}C$까지 대략 1$0^{\circ}C$/Ma의 냉각속도를 구할 수 있었다. 청주화강암의 쥬라기 중기 연대는 영광-대전-청주-충주-원주-강릉 지역의 화강암질 저반이 대동누층군 퇴적 이후에 일어난 지구조 사건과 연관되었을 가능성을 지시하지만 이를 확인하기 위해서는 더 많은 자료가 요구된다. 우리는 현재 충주, 괴산 지역의 화강암체에 대해서도 스핀 연대측정을 수행중에 있으며 이들 자료를 암상을 구분하여 해석한다면 우리나라 중생대 지구조운동에 대한 새로운 사실이 밝혀질 수 있을 것으로 믿는다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.6
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• pp.49-59
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• 2012

Recently, various alternatives for safety and efficiency of commercial vehicles have been considered, and one of the new alternatives is the application of a digital tachograph. In Korea, the installation of a digital tachograph to commercial vehicles was regulated from 2011 and Korea Transportation Safety Authority developed e-TAS to analyze the monitoring data from digital tachographs installed in the order of 100 commercial vehicles. This study performs the potential impact analysis of the DTG installation, which includes a trend of dangerous driving, a trend of traffic accidents and cost-effective analysis, a trend of fuel consumption and cost-effective analysis, a cost-effective analysis of social benefits using e-TAS data. Depending on the frequency of dangerous driving, the participants are divided into three groups; high-dangerous group, average-dangerous group and low-dangerous group. The high-dangerous driving group shows lower km/liter than the low-dangerous driving group by 15% for buses and taxis and by 30% for trucks. About $CO_2$ emission, the difference becomes bigger; 25%, 25% and 42% for buses, taxis and trucks, respectively. Although this study is a short-term period analysis, the methodology will be applicable for the long-term period analysis with larger data.