• Journal of the Korean Geophysical Society
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• v.2 no.1
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• pp.27-38
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• 1999

The errors between track segments or at the cross-over points of shipborne gravity were successfully reduced by applying a cross-over error adjustment technique using satellite gravity. The integration of shipborne and satellite altimeter-implied free-air gravity anomalies after the cross-over error adjustment resulted in a high resolution gravity map which contains both short and long wavelength components. The successful adjustment of the cross-over errors in the shipborne gravity using the satellite gravity suggests that the shipborne gravity can be combined with the satellite anomalies characterized by a stable and long wavelength component. The resulting free-air anomaly map is evenly harmonized with both short and long wavelength anomalies. Thus the corrected anomaly map can be better used for the geological interpretation. Free-air anomalies with more than 140 mGal in total variations generally correspond to the seafloor topographic changes in their regional patterns. A series of gravity highs are aligned from the Korea Plateau to the Oki Island, which are interpreted to be caused by seamounts or volcanic topographies. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably responsible for the thin crust and shallow seated mantle. The gravity minima along the western and southern shelf edge are associated not only with the local basement morphology and thick sediment fill at the continental margin, but also possibly with the crustal edge effect known for passive continental margins. Series of NE-trending linear anomalies are possibly caused by a swarm of volcanic intrusions followed the initial opening of the Ulleung Basin. The linear high anomalies in the Ulleung Plateau are terminated by the straightly NNW-trending anomalies with a sharp gradient in its western boundary which indicates a fault-line scarp. The opposite side adjoined with the fault-line scarp shows no correlation with the fault-line scarp in geometry indicating that the block might be horizontally slided from the north. A gravity high in contrast to the deepening in seafloor toward the northeastern central Ulleung Basin is probably suggestive of a thin crust and shallow seated mantle.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.24-45
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• 2002

For the last several decades, high-resolution shallow marine seismic technique has been used for various resources, engineering and geological surveys. Even though the multichannel method is powerful to image subsurface structures, single channel analog survey has been more frequently employed in shallow water exploration, because it is more expedient and economical. To improve the quality of the high-resolution seismic data economically, we acquired digital seismic data using a small air gun, 6 channel streamer and PC-based system, performed data processing and produced high-resolution seismic sections. For many years, such test acquisitions were performed with other studies which have different purposes in the area of off Pohang, Yellow Sea and Gyeonggi-bay. Basic data processing was applied to the acquired data and the processing sequence included gain recovery, deconvolution, filtering, normal moveout, static corrections, CMP gathering and stacking. Examples of digitally processed sections were shown and compared with analog sections. Digital seismic sections have a much higher resolution after data processing. The results of acquisition and processing show that the high-resolution shallow marine seismic surveys using a small air gun, 6 channel streamer and PC-based system may be an effective way to image shallow subsurface structures precisely.

• 한국지구물리탐사학회:학술대회논문집
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• 1999.08a
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• pp.137-155
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• 1999

Recently, Televiewer(Borehole Acoustic Scanner(Televiewer)) has come to be widely used specially for the general engineering construction design. The Televiewer tool using a focussed acoustic beam is to detect the amplitude and traveltime of each reflected acoustic signal at the wall, resulting in the amplitude- and traveltime image respectively. Fractures can be well detected, because they easily scatter the acoustic energy due to the highly narrow beam. In addition, the drilling work will rough the borehole wall so that the acoustic energy can be scattered simply due to the roughness of the wall. Thus, the amplitude level can be directed associated with the elastic properties(impedance) and the hardness of the rock as well. Meanwhile, the traveltime image provides an information about the borehole shape and can be converted to a high precision 3D caliper log(max. 288 arms). In this paper, based on the high resolution of Televiewer images, general evaluation methods are illustrated to derive very reliable rock parameters.

• Journal of the Korean Vacuum Society
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• v.18 no.1
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• pp.66-72
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• 2009

The detection methods are required to monitor and diagnose the abnormality on the insulation condition inside a gas-insulated switchgear (GIS). Due to a good sensitivity to the products decomposed by partial discharges (PDs) in $SF_6$ gas, the development of a SWNT gas sensor is actively in progress. However, a few numerical studies on the diffusion mechanism of the $SF_6$ decomposition products by PD have been reported. In this study, we modeled $SF_6$ decomposition process in a chamber by calculating temperature, pressure and concentration of the decomposition products by using a commercial CFD program in conjunction with experimental data. It was assumed that the mass production rate and the generation temperature of the decomposition products were $5.04{\times}10^{-10}$ [g/s] and over 773 K respectively. To calculate the concentration equation, the Schmidt number was specified to get the diffusion coefficient functioned by viscosity and density of $SF_6$ gas instead rather than setting it directly. The results showed that the drive potential is governed mainly by the gradient of the decomposition concentration. A lower concentration of the decomposition products was observed as the sensors were placed more away from the discharge region. Also, the concentration increased by increasing the discharge time. By installing multiple sensors the location of PD is expected to be identified by monitoring the response time of the sensors, and the information should be very useful for the diagnosis and maintenance of GIS.

• Korean Journal of Plant Resources
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• v.25 no.5
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• pp.624-632
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• 2012

As there have been lately many worldwide resource challenges such as potential exhaustion of fossil fuels, sudden rise of oil price and ever-rising grain pricing due to global food crisis, there have been more interests focused on recycling vegetable oils and fats into clean natural fuel and producing new resources based on waste cooking oil as a part of reusing waste resources. An Experiment was performed by using ratio of 50:50, 75:25 (w/w) mixture of based rapeseed oil, camellia oil, and olive oil. 50:50, 25:75 (w/w) mixture of based palm oil. The result was that the oleic acid ($C_{18:1}$) got the lowest percentage of 42.8%, when we combined the mixture of rapeseed oil and soybean oil. While the highest percentage of 72.1% was when the mixture of camellia oil and rapeseed oil were combined at 50:50 ratio. In 75:25 (w/w) case, mixture of rapeseed oil and soybean oil got the lowest. The highest ratio was the mixture of camellia oil and olive oil. Based on the component of palm oil, the total saturated fatty acid was decreased. It is expected that stabilizing oxidation through controlling of fatty acid after mixture and that liquidity at a low temperature. The acid value indicated that stabilizing oxidation got a range of highest to lowest. Camellia oil ranked as the highest, followed by olive oil, and the oil seeds as the lowest in rank. Controlling iodine value through mixture and improvement of stabilizing oxidation will provide a good quality. The quality of color has no significant change about mixture in ratio and maintenance. The reduction of the cost of refining process is expected by controling of mixture ratio at biodiesel production in the future.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.156-168
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• 2012

Chrysanthemum is a cut flower species that normally lasts for 1 to 2 weeks, in some cases 3-4 weeks. This has been attributed to low ethylene production during senescence. Reduction in cut flower quality has been attributed to the formation of air embolisms that partially or completely blocks the water transport from the vase solution to the rest of the cut flower stem, increasing hydraulic resistance which may cause severe water stress, yellowing, wilting of leaf, and chlorophyll degradation. Standard type chrysanthemum can be harvested when buds were still tightly closed and then fully opened with the simple bud-opening solution. Standard type chrysanthemum can also be harvested when the minimum size of the inflorescence is about 5-6 cm bud which opened into the first flower full-sized flower. While spray varieties can be harvested when 2-4 most mature flowers have opened (40% opening). Cut flowers are sorted by stem length, weight, condition, and so on. Standard chrysanthemum is 80 cm length for standard type and 70cm for spray type. Pre-treatment with a STS, plant regulator such as GA, BA, 1-MCP, chrysal, germicide, and sucrose, significantly improved the vase life and quality of cut flowers. It is well established that vase solutions containing sugar can improve the vase life of cut chrysanthemum. Chrysanthemum is normally packed in standard horizontal fiberboard boxes. Chrysanthemum should normally be stored at $5{\sim}7^{\circ}C$. Precooling resulted in reduction in respiration, decomposition, and transpiration activities as well as decoloration retardation. There was significant difference between "wet" storage in 3 weeks and "dry" storage in 2 weeks. In separate pulsing solution trials, various germicides were tested, as well as PGRs to maintain the green color of leaves and turgidity. Prolonging vase life was attained with the application of optimal solution such as HQS, $AgNO_3$, GA, BA and sucrose. This also retarded senescence in leaves of cut flower stems. Fresh cut chrysanthemum can be transported using a refrigerated van with $5{\sim}7^{\circ}C$. Increasing consumption and usage of cut chrysanthemum of various cultivars would require efficient transport system, and effective information exchange among producer, wholesaler, and consumer.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.10 no.3
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• pp.207-214
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• 2016

The aim of this study was to evaluate Influence on intra-limb coordination in individuals wearing knee brace during walking. Seven healthy male adults ($32.3{\pm}2.7$ years old, $175.2{\pm}3.8cm$, $76.2{\pm}8.7kg$) participated. They wore knee brace or didn't wear any knee brace and were asked to walk along a 10 m long walkway. Spatiotemporal parameters, angles of the lower limbs, and intra-limb continuous relative phase (CRP) were measured and calculated. No differences of spatiotemporal parameters were shown (all p > 0.05). There were no changes in the angle and its range of motion (ROM) in the hip for the subjects as wearing knee brace, while ROM ($65.5{\pm}3.7^{\circ}$ vs. $60.5{\pm}3.5^{\circ}$, p < 0.05) of the angle and maximum flexion angles (stance: $31.9{\pm}4.6$ vs. $25.6{\pm}5.5$, swing: $76.7{\pm}3.1$ vs. $68.9{\pm}3.4$, all p < 0.05) in the knee significantly decreased. No changes in ROM of angle in the ankle were shown, whereas maximum dorsiflexion decreased ($22.4{\pm}2.6$ vs. $19.2{\pm}2.1$, p < 0.05) and maximum plantarflexion increased ($9.5{\pm}3.0$ vs. $15.7{\pm}2.2$, p<0.05). There were no changes in most of CRP between joints. CRP between the hip and knee joints decreased ($93.0{\pm}7.8$ vs, $84.7{\pm}4.9$, p < 0.05). Most of CRP standard deviation increased (between the hip and ankle joint during swing: $25.1{\pm}6.7$ vs. $32.4{\pm}1.9$, between the knee and ankle joint during stance: $46.0{\pm}12.9$ vs. $80.1{\pm}31.1$, between the knee and ankle joint during swing: $34.5{\pm}4.1$ vs. $37.6{\pm}3.1$, all p < 0.05). These results indicated that wearing knee brace affected joint angle and intra-limb coordination, but less affected gait features.

• Journal of Gifted/Talented Education
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• v.16 no.1
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• pp.21-42
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• 2006

The object of this research is to analyze the contents and amount of articles on gifted education in major daily newspapers dated January 1990 to December 2003, and to review the trend of social perception of gifted education with the passage of time. Following are the research question : 1. How many articles belonging to the same category appeared in the newspapers within the period of time covered by the study? 2. What kinds of articles appeared in the newspapers within the period of time covered by the study? To arrive at the answers to the problems mentioned above, 714 articles on gifted education. The period from 1990 to 2003 were divided into time frames of 5 years to facilitate the analysis of social consciousness regarding gifted education before and after the enforcement of the Early School Entering Law in 1995 and the Law for Promotion of Gifted Education in 2000. The researcher defined Period I as the years from 1990 to 1994, Period II from 1995 to 1999, and Period III from 2000 to 2003. The articles were classified by content which were significance and trend of gilled education, current policies on gifted education, information on gifted education, and social environment of gifted education. The results of the analysis are as follows: (1) The articles from 1990 to 2003 totalled 714. 130 articles were found within Period I, 213 within Period II, and 371 within Period III. Since the year 2000, when the Law for Promotion of gifted education was enforced, the amount of articles considerably increased. The articles on the trend of gifted education numbered 42 within Period I, 49 within Period II, and 81 within Period III, showing a huge increase in the last period. The articles on current policies numbered 56 within Period I, 77 within Period II, and 143 within Period III, numbering the most in the last period. This means that, even before the Law for Promotion of gifted education was enforced, there has been much interest in and discussion of the appropriate educational system for gifted children in preparation for the legal and institutional foundation of such system. Since the enforcement of the law, many institutions were established and the problem became an important social issue. The articles that most frequently appeared were about current policies on and status of gifted education. This category showed the largest numbers through all the three periods and on all the subjects. This subject represented 43.1% of the articles on gifted children within Period I, 36.2% within Period II, and 38.6% within Period III. As to the significance and trend of gifted education, this subject showed a decrease from 32.3% within Period I, 23% within Period II, and 21.8% within Period III. However, the articles in the category of information on gifted education gradually increased from they represented 5.4% of the articles on brilliant children within Period I, 7.5% within Period II, and 8.4% within Period III. The social environment articles showed an increase from Period I to Period II-- from 19.2% to 33.3%, but it went down to 31.3% within Period III. (2) As to articles on the trend of gifted education, there were many such articles found, mainly on researches and trends in other countries. As greater importance is accorded to gifted children and as the recognition of the necessity of providing specific education for them grows, more related studies are conducted and people try to adopt new trends from other countries. For the articles on the current policies of gifted education, most of them were about institutions. This means that many educational institutions have been established since the Law for Promotion of Gifted Education was enforced. Informative articles on gilled education were mostly about distinctive features of gifted children and how to tell who the brilliant children are. This fact shows the importance of identifying gifted children in order to educate them systemically and effectively.

• Journal of Gifted/Talented Education
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• v.25 no.6
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• pp.837-856
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• 2015

The purpose of this study was to examine the effects of ill-structured problem solving program on the social self-efficacy, democratic citizenship, and meta-cognition of the scientifically gifted high school students and provide an opportunity to consider how to improve students' social self-efficacy, democratic citizenship, and meta-cognition when comprehensive character education has been emphasized in science programs for gifted students. The subjects consisted of 17 students(10th graders) and 19 students(11th graders) who were participated in a science gifted program in a Korean high school located in Seoul and pre-examination on their social self-efficacy, democratic citizenship, and meta-cognition was conducted. After applying 12-class-time of ill-structured problem solving program, post-examination on their social self-efficacy, democratic citizenship, and meta-cognition was conducted and student's self-essay about program was also conducted. Paired t-test was used to analyze the data collected and students's self-essays were also analyzed. The results of this study were as follows: First, the findings showed that ill-structured problem solving program developed students' social self-efficacy and especially showed a significant improvement in asking for help. Second, they also showed that ill-structured problem solving program raised students' democratic participation especially in a democratic function. Third, in terms of meta-cognition, ill-structured problem solving program also played a positive role. The result of analyzing students' essays also showed students' positive perception on the program. The findings of the present study suggested that ill-structured problem solving program should be taken into consideration when developing a science program for scientifically gifted high school students.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.361-370
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• 2011

This study was conducted to obtain basic a information on growth characteristics, productivity, and feed values of whole crop barleys with different awn types. The field experiments were conducted on land at Iksan, Jeollabuk-do province in Korea for one year. Six barleys with three different awn types, such as Youngyang (rough), Yuyeon (hood), Youho (hood), Iksan449 (hood), Iksan456 (hood), and Iksan448 (awnless), were used in this study. Barleys were harvested on five growth stages after (DAH); 20 days after heading (20 DAH), 25 DAH, 30 DAH, 35 DAH, and 40 DAH. Heading was earlier in Yuyeon (April 22), while was later in Iksan448 (April 29). The maximum dry matter and total digestible nutrients (TDN) yields, 11.8 and 8.1 ton per ha, respectively, was recorded in Ikan456 harvested at 35~40 DAH, followed by Youngyang, Yuyeon, Iksan448, Youho and the lowest in Iksan449. They were increased significantly with advancing crop maturity. Crude protein content was the highest in Iksan448 (10.9%) and the lowest in Youho (9.7%) and that was decreased significantly with late harvest. Total digestible nutrients (TDN) and relative feed value (RFV) were the highest in Iksan448 (73.0%, 183.8, respectively) and the lowest in Iksan456 (68.0%, 135.4, respectively) and they were increased significantly with late harvest. The mean RFV evaluated by awn types was the highest in Iksan448 (183.8) of awnless, the lowest in Youho (149.5) and Iksan456 (135.4), indicated the insufficiency of hooded type barleys as good fodder use. Therefore, in this study suggest that hooded barley should improve forage productivity as well as quality.