• Korean Journal of Environment and Ecology
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• v.23 no.2
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• pp.177-186
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• 2009

In the flora of the whole area of Jakeundang at Byeonsanbando National Park, a total of 105 taxa were identified including 50 families, 88 genera, 98 species, 6 varieties and 1 form. These were again divided into 31 taxa (29.5%) of woody plants and 74 taxa (70.5%) of herbaceous plants. In addition, 4 taxa of the Korea Forest Service, designated rare plants in the flora were identified to grow there including Phacelurus latifolius (Preservation priority order: No. 194), Aristolochia contorta (No. 151), Koelreuteria paniculata (No. 115), and Glehnia littoralis (No. 203). Indigofera koreana, Viola seoulensis that are on the list of Korean endemic plants were also identified and the plants approved for export were identified similarly to rare plants. In addition, among the floral region-based specific plants, the plant group belonging to class V, class IV and II didn't appear and a total of 16 taxa 3 taxa including Elymus mollis, Salsola collina and Koelreuteria paniculata in class III, and 13 taxa including Ischaemum anthephephoroides, Phacelurus latifolius, Asparagus cochinchinensis, Melandryum oldhamianum for. roseum, Calystegia soldanella, Messerschmidia sibirica, Scutellaria strigillosa and Aster spathulifolius, etc. in class I were identified. Among the naturalized plants in the surveyed sites, 6 families, 10 genera, and 10 taxa were identified to grow, such as Bromus unioloides, Phytolacca americana, Lepidium apetalum, Robinia pseudoacacia, Oenothera biennis and Xanthium canadense, etc. and the naturalization rate was analyzed to be 9.5% of all 105 taxa of vascular plants. This research analyzed the coverage ratio and importance value by dividing the community into a sand dunes and back swamp and divided the sand dune area into Vitex rotundifolia community and the back swamp into Phacelurus latifolius community. Jakeundang is designated as a sand dune plants observation area and managed by the office of Byeonsanbando National Park. To preserve this place, it is desirable to take a systematic management measure, such as a visit to this place on a subscription basis or education and publicity on sand dune plants.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.581-584
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• 2008

The catalyst carriers of the mesoporous layer compounds were prepared to carry out the partial oxidation of methane(POM) to hydrogen. The catalytic activities of POM to hydrogen were investigated over Ru(3)/SPK and Ru(3)/SPM catalyst in a fixed bed flow reactor under atmosphere. In addition, the catalysts and carriers were characterized by BET, TEM, TPR. The BET surface areas of the silica-pillared $H^+-kenyaite$(SPK) and the silica-pillared $H^+-magadite$(SPM) were $760m^2/g$ and $810m^2/g$, repectively, and the average pore sizes were 3.0 nm and 2.6 nm, repectively. The nitrogen adsorption isotherms were type IV with developed hysteresis. The TEM showed that the mesoporous layer compounds were formed well. The Ru(3)/SPK and the Ru(3)/SPM catalyst were obtained high hydrogen yields(90%, 87%), and were kept constant high hydrogen yields even about 60 hours at 973 K, $CH_4/O_2=2$, $1.25{\times}10^{-5}g-Cat.hr/ml$. The TPR peaks of Ru(3)/SPK and the Ru(3)/SPM catalyst showed the similar reducibilities around 453 K and 413 K. It could be suggested that SPK and SPM had the physicochemical properties as oxidation catalyst carries from these analysis data.

• Journal of Global Scholars of Marketing Science
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• v.19 no.2
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• pp.17-26
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• 2009

As the lifestyle of consumers changes and the need for various products increases, new products are being developed in the market. Each household owns various home appliances which are purchased through the choice of a decision maker. These appliances include not only large-sized products such as TV, refrigerator, and washing machine, but also small-sized products such as microwave oven and air cleaner. There exists latent correlation among possession of home appliances, even though they are purchased independently. The purpose of this research is to analyze the effect of demographic factors on the purchase and possession of each home appliances, and to derive some relationships among various appliances. To achieve this purpose, the present status on the possession of each home appliances are investigated through consumer survey data on the electric and energy product. And a multivariate probit(MVP) model is applied for the empirical analysis. From the estimation results, some appliances show a substitutive or complementary pattern as expected, while others which look apparently unrelated have correlation by co-incidence. This research has several advantages compared to previous literatures on home appliances. First, this research focuses on the various products which are purchased by each household, while previous researches such as Matsukawa and Ito(1998) and Yoon(2007) focus just on a particular product. Second, the methodology of this research can consider a choice process of each product and correlation among products simultaneously. Lastly, this research can analyze not only a substitutive or complementary relationship in the same category, but also the correlation among products in the different categories. As the data on the possession of home appliances in each household has a characteristic of multiple choice, not a single choice, a MVP model are used for the empirical analysis. A MVP model is derived from a random utility model, and has an advantage compared to a multinomial logit model in that correlation among error terms can be derive(Manchanda et al., 1999; Edwards and Allenby, 2003). It is assumed that the error term has a normal distribution with zero mean and variance-covariance matrix ${\Omega}$. Hence, the sign and value of correlation coefficients means the relationship between two alternatives(Manchanda et al., 1999). This research uses the data of 'TEMEP Household ICT/Energy Survey (THIES) 2008' which is conducted by Technology Management, Economics and Policy Program in Seoul National University. The empirical analysis of this research is accomplished in two steps. First, a MVP model with demographic variables is estimated to analyze the effect of the characteristics of household on the purchase of each home appliances. In this research, some variables such as education level, region, size of family, average income, type of house are considered. Second, a MVP model excluding demographic variables is estimated to analyze the correlation among each home appliances. According to the estimation results of variance-covariance matrix, each households tend to own some appliances such as washing machine-refrigerator-cleaner-microwave oven, and air conditioner-dish washer-washing machine and so on. On the other hand, several products such as analog braun tube TV-digital braun tube TV and desktop PC-portable PC show a substitutive pattern. Lastly, the correlation map of home appliances are derived using multi-dimensional scaling(MDS) method based on the result of variance-covariance matrix. This research can provide significant implications for the firm's marketing strategies such as bundling, pricing, display and so on. In addition, this research can provide significant information for the development of convergence products and related technologies. A convergence product can decrease its market uncertainty, if two products which consumers tend to purchase together are integrated into it. The results of this research are more meaningful because it is based on the possession status of each household through the survey data.

• The Korean Journal of Air & Space Law and Policy
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• v.35 no.3
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• pp.95-126
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• 2020

In 2017, the world's first WIG ship (WIG: Wing In-Ground) pilot's license written test was conducted in Korea. The WIG ship is a ship that combines the characteristics of ships and airplanes. Therefore, the pilot of the WIG ship was allowed to apply only for those who had the aircraft pilot's license and the 6th class marine nautical license. The WIG ship pilot's license system was first introduced by Korea, so there are no international standards for the license system, and the introduction of a domestic qualification system also requires institutional arrangements due to various restrictions such as pilot training. However, in order to become a valuable industry as a future growth engine for the ocean, several urgent problems need to be solved, and that is the training of manpower for WIG ships. Therefore, I reviewed the institutional issues related to pilot training as this subject. Since 2001, various countries around the world have been discussing this issue, centering on IMO, and Korea has continued to participate and cooperate in IMO meetings. And the national qualification test for surface flying ships was conducted in Korea from 2011. However, there are still problems to be solved, and I pointed out the advancement of the manpower training system, the education and training system, and the designated national educational institution system. As a solution to this, it was suggested through the improvement of the license system and the operation of designated educational institutions. Among these solutions, I believe that the best way is to entrust the operation of designated national educational institutions to private educational institutions. However, I propose a plan that the government entrusts to private educational institutions, but the government is responsible for licensing and supervision. WIG ship will be a new market for the aviation industry and aviation workers.

• Journal of Animal Environmental Science
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• v.9 no.2
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• pp.123-130
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• 2003

In this study, current status of domestic deer farms and its feeding were surveyed. The information of supply and demand of feed f3r deers including its industry were also examined and then analyzed to make fundamental data for deer farms and government policy. The results are as follows. 1. Over 40 years old farmers were about 63％ of total deer farms while 20­30 years olds were less than 1％ indicating that young people still evade agriculture. Moreover, considering education, over 52％ of the farmers have bachelor degree showing much higher rates compared to the other agricultural fields. The reason can be assumed that the labor burden is not serious in deer farming while it is not dirty job compared to the other livestock management. Those high­educated people can be easily trained as experts of deer farming to improve its international competition. 2. Most of investigated farms raise Korean spotted deers and Elk showing that the percentage of Elk has greatly increased(However, many farmers have complained about purchasing methods and they insisted that the sales organization should be controlled by government). 3. 57％ of total cost of production is for feed while most of feeds are imported from abroad. It indicated that it is urgent to make counterplan for saving feed cost. 4. It is necessary to develop feeds for deers in the near future while most of the examined farmers currently use normal assorted feed. Typical roughage sources feeds are rice straw, alfalfa hay, browses feed, and so on. Most of them are currently imported except the rice straw indicating urgently needed to develop domestic bulky feed. 5. The present questions are development of processed goods of velvet antler, establishment of reasonable management system, difficulty of velvet antler selling, feed supply, and so on. It is necessary for government and academic world to develop reasonable policy and scientific research program.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.3
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• pp.3-9
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• 2017

Recently, in 3rd Generation Partnership Project(3GPP), there is a study of the Long Term Evolution(LTE) based vehicle communication which has been actively conducted to provide a transport efficiency, telematics and infortainment. Because the vehicle communication is closely related to the safety, it requires a reliable communication. Because vehicle speed is very fast, unlike the movement of the user, radio channel is rapidly changed and generate a number of problems such as transmission quality degradation. Therefore, we have to continuously updates the channel estimates. There are five types of conventional channel estimation scheme. Least Square(LS) is obtained by pilot symbol which is known to transmitter and receiver. Decision Directed Channel Estimation(DDCE) scheme uses the data signal for channel estimation. Constructed Data Pilot(CDP) scheme uses the correlation characteristic between adjacent two data symbols. Spectral Temporal Averaging(STA) scheme uses the frequency-time domain average of the channel. Smoothing scheme reduces the peak error value of data decision. In this paper, we propose the novel channel estimation scheme in LTE based Vehicle-to-Vehicle(V2V) environment. In our Hybrid Reliable Channel Estimation(HRCE) scheme, DDCE and Smoothing schemes are combined and finally the Linear Minimum Mean Square Error(LMMSE) scheme is applied to minimize the channel estimation error. Therefore it is possible to detect the reliable data. In simulation results, overall performance can be improved in terms of Normalized Mean Square Error(NMSE) and Bit Error Rate(BER).

• Economic and Environmental Geology
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• v.53 no.1
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• pp.1-9
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• 2020

Magnesium silicate minerals such as serpentine [Mg₃Si₂O₅(OH)₄] have a high potential for the sequestration of CO₂; thus, their reactivity toward dissolution under CO₂-free and CO₂-containing conditions in acidic solvents is a critical process with respect to their carbonation reactions. To examine the carbonation efficiency and dissolution mechanism of serpentine, hydrothermal treatment was performed to the starting material via a modified direct aqueous carbonation process at 100 and 150℃. The serpentine dissolution experiments were conducted in H₂SO₄ solution with concentration range of 0.3-1 M and at a CO₂ partial pressure of 3 MPa. The initial pH of the solution was adjusted to 13 for the carbonation process. Under CO₂-free and CO₂-containing conditions, the carbonation efficiency increased in proportion to the concentration of H₂SO₄ and the reaction temperature. The leaching rate under CO₂-containing conditions was higher than that under CO₂-free conditions. This suggests that shows the presence of CO₂ affects the carbonation reaction. The leaching and carbonation efficiencies at 150℃ in 1 M H₂SO₄ solution under CO₂-containing conditions were 85 and 84%, respectively. The dissolution rate of Mg was higher than that of Si, such that the Mg : Si ratio of the reacted serpentine decreased from the inner part (approximately 1.5) to the outer part (less than 0.1). The resultant silica-rich layer of the reaction product ultimately changed through the Mg-depleted skeletal phase and the pseudo-serpentine phase to the amorphous silica phase. A passivating silica layer was not observed on the outer surface of the reacted serpentine.

• Journal of the Korean Society of Radiology
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• v.11 no.2
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• pp.145-155
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• 2017

The purpose of this study was to compare and analyze changes in body composition and bone mineral density (BMD) during combined exercise in premenopausal women who did not take regular diet or regular physical activity within 6 months, In addition to being able to recognize the importance of pre-menopausal women's health and exercise, it also provides basic data for the development of educational programs for early prevention of osteoporosis prevention education I want to. The average age of the subjects in their 30s was 35.44 years and their height was 158.89 cm in their 30s. The average age of the subjects in their 40s was 41.89 and their average height was 160.78 cm in their 40s. Body composition, BMI, and body fat percentage were higher in the 30s, and bone mineral content, lean body mass, skeletal muscle mass, body weight, body fat mass and waist circumference were higher in their forties. Lumbar spine BMD and femur density were higher in their 30s than their 40s. Body composition, skeletal muscle mass, and fat mass increased in the 30s body composition by age - related complex exercise in premenopausal women, body fat mass, body fat percentage, waist circumference decreased. Body mass, body fat, body fat percentage, and BMI decreased in the 40s. The lumbar spine, the lumbar spine, the lumbar spine, and the femur were increased in the lumbar spine, the lumbar spine, the femur, and the femur. In the post-analysis results, changes in body composition were statistically significant due to decrease in muscle mass, body weight, body fat mass and BMI after combined exercise. In the change of bone density, lumbar spine BMD was measured as lumbar spine 1, lumbar spine 2, lumbar spine 3, And the femur density was increase.

• Food Science of Animal Resources
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• v.26 no.4
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• pp.532-539
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• 2006

This study was conducted to evaluate the inhibitory effects of exopolysaccharide(EPS) produced by Streptococcus thermophilus BODY1 on rotavirus(RV). EPS was isolated from a commercial lactic acid bacteria, Str. thermophilus BODY1. The results obtained were as follows : At 0.1% of EPS, inhibitory effects of EPS on the MA-104 cell using MTT assay were, $Wa\;51.58{\pm}8.08%,\;KU \;63.09{\pm}7.58%,\;S2\;51.23{\pm}5.43%,\;YO\; 51.45{\pm}5.67%,\;K-21\;52.84{\pm}5.49%,\;NCDV\;57.50{\pm}10.85%,\;UK\;51.64{\pm}4.74%,\;KK3\;54.53{\pm}8.44%,\;JBR\;58.67{\pm}7.51%,\;S97\;50.63{\pm}5.17%,\;OSU\;55.48{\pm}5.75%,\;and\;RRV\;54.36{\pm}8.72%$, respectively. At 0.1/128%, the effects were $Wa\;5.5{\pm}6.45%,\;KU\;10.33{\pm}8.39%,\;S2\;0.98{\pm}8.39%,\;YO\;4.25{\pm}2.86%,\;K-21\;4.25{\pm}6.60%,\;NCDV\;4.01{\pm}4.12%,\;UK\;6.55{\pm}7.09%,\;KK3\;5.19{\pm}4.86%,\;JBR\;11.11{\pm}8.11%,\;S97\;6.75{\pm}6.95%,\;OSU\;10.14{\pm}8.54%,\;and\;RRV\;3.66{\pm}8.57%$, respectively. These results indicate that EPS have inhibitory effects on various serotype and sources of RV from different animals.

• Korean Journal of Social Welfare
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• v.57 no.3
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• pp.73-103
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• 2005

This study takes of youth panel data(2002-2003), there is the purpose to know to youth employed's labor mobility conditions of employment status conversion and examine on factors affecting conversion of employment status. Main analysis result and policy imply, is as following. First, although youth employed's non-standard employment shows some decrease, employment youth hierarchy was construed that youth of our country is consisting very changefully because appear great turnover that is converted by unemployment or Not economically activity population same period. Specially, non-standard employment phenomenon of woman or low in scholarship person appeared notedly, and because phenomenon that is converted by unemployment or Not economically activity population is expose that is deepened, discriminating policy of government dimension is required for employment stabilization of these class. Second, show result that danger to escape to non-standard job risk trap which seeking employment activity of youth class is arranged case or company which is formed by official path is suitable becomes low, must formulate path of employment about youth class and improve qualitative level of employment through suitable job placement education of youth class or function (technology) level. Third, when was construed, but take into account that the although large enterprise have low risk in non-standard job, recently employment of youth class consists very limited, rather small scale business or smaller enterprise's competitive power preferably need to be plan. Finally, danger to non-standard job youth employed's company form is government connection wonder was expose that high, Such result can do that it is difficult by limited research period, but reflect actuality that youth unemployment policy of our country is enforced laying stress on public labor or unregular job employment such as internship system. Therefore, current youth unemployment policy may have to change by employment policy that can secure stable work record by youth class or act as bridge-building that promote conversion by full-time job.