• Toxicological Research
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• v.21 no.2
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• pp.179-186
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• 2005

Dimethylamine (DMA) is a widely used commodity chemical with few toxicity data. Groups of 10 male and female F-344 rats were exposed by inhalation to 0, 5, 10, 20, 40 and 80 ppm of DMA for 6 hrs/day, 5 days/week for 90 days. The changes of body weight, organ weight, hematology, clinical chemistry, and histopathological changes were evaluated after the exposure. As the results, the body weight was significantly decreased at 80 ppm in male and female rats (p<0.05). The absolute lung weight showed no statistically significant changes in any group. In contrast, the relative lung weight significantly increased at 80 ppm in male and female rats (p<0.05). Erythrocytes, mean cell hemoglobin, leukocytes, neutrophil, and platelet numbers were significantly increased in male and female at 40 or 80 ppm of DMA (p<0.05, p<0.01). In addition, the serum values of total protein, urea nitrogen were increased in male and creatine kinase, total protein were increased in female rats at 40 or 80 ppm (p<0.05, p<0.01). Histopathological examinations of the male and female lung samples showed slight hyperplasia and congestion at 80 ppm. Taken together, our study revealed that maximum tolerated dose of DMA would be over 40 ppm.

• Management & Information Systems Review
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• v.34 no.1
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• pp.179-190
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• 2015

Local governments are commercializing natural environment, one of tourist commodities, to ensure that the proceeds from sale of tourist commodities are returned to local residents(Han Yeong-joo, Lee Moo-yong, 2001). In Songdo beach, Busan, cable car dismantled in 1980s due to the run-down state of the facility is poised for restoration in 26 years and can be said to be of great value as tourist commodity of the region and necessitates the demand forecast. To overcome limitations of demand forecast in existing studies, the analysis was made based on feasibility rate(Gruber index, self-confidence index), the realizable predictive value, for the willingness-to-visit rate when forecasting the demand of visitors. The results of demand forecast suggested that number of visitors would range from approximately 550,684 persons to 1,514,416 persons when the target region for demand forecast was confined to Busan Metropolitan City, and was in the range between 1,013,740 persons and 2,854,340 persons when the target region was expanded to cover Busan, Ulsan, and Gyeongnam. Based on the results of this study, estimation of visitors and demand forecast for Songdo offshore cable car restoration which reflect characteristics of Songdo beach of Busan would provide important basis for proceeding with tourism industry development project.

• Journal of Digital Convergence
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• v.10 no.9
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• pp.27-37
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• 2012

Internet privacy has become a significant issue in recent years in light of the sharp increase in internet-based social and economic activities. The technology which collects, processes and disseminates personal information is improving significantly and the demand for personal information is rising given its inherent value in regard to targeted marketing and customized services. The high value placed on personal information has turned it into a commodity with economic worth which can be transacted in the marketplace. Therefore, it is strongly required to approach the issue of privacy from economic perspective in addition to the prevailing approaches. This article analyzes the behaviors of consumers and firms in gathering personal information, and shielding it from unauthorized access, using a game theory framework in which players strive to do their best under the given conditions. The analysis shows that there exist no market forces which require all firms to respect consumer privacy, and that government intervention in the form of a nudging incentive for information sharing and/or strict regulation is necessary.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.11
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• pp.1515-1527
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• 2016

With the growth of big data, machine learning, and cloud computing, the importance of storage that can store large amounts of unstructured data is growing recently. So the commodity hardware based distributed file systems such as MAHA-FS, GlusterFS, and Ceph file system have received a lot of attention because of their scale-out and low-cost property. For the data fault tolerance, most of these file systems uses replication in the beginning. But as storage size is growing to tens or hundreds of petabytes, the low space efficiency of the replication has been considered as a problem. This paper applied erasure coding data fault tolerance policy to MAHA-FS for high space efficiency and introduces VDelta technique to solve data consistency problem. In this paper, we compares the performance of two file systems, MAHA-FS and GlusterFS. They have different IO processing architecture, the former is server centric and the latter is client centric architecture. We found the erasure coding performance of MAHA-FS is better than GlusterFS.

• Journal of Korea Port Economic Association
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• v.31 no.4
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• pp.1-15
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• 2015

During global recessions, such as the 2008 financial crisis, Korean shipping companies have been undergoing a liquidity crisis that is comparably worse than other shipping companies worldwide. One of the reasons behind this repetitive vicious cycle can be the lack of ability to foresee the future by analyzing and understanding the volatile shipping market. Traditionally, in order to assimilate the shipping market, larger Korean shipping companies have been purchasing market reports published by Europe-based research companies and shipping brokers, leading to a digital divide by company size. To resolve this issue, the Maritime Exchange Information Center (MEIC) has been publishing shipping market reports that include essential shipping information such as freight rates by different routes; commodity trends for iron ore, grain, and coal; ship-building trends for new-building, second-hand, and demolition markets; as well as bunker price and port congestion. This research was conducted to analyze the effectiveness of four variables-information usefulness, market reflection, information composition, and latest information-on information satisfaction. If the information satisfaction was found to be adequate, the analysis of actual proof was used to determine if the customers would be willing to purchase MEIC's report when it is chargeable. All the four variables were found to have positive effects on information satisfaction. In particular, latest information was found to directly affect the intention to purchase. Furthermore, high information satisfaction was related to the intention to purchase.

• Journal of Korean Home Economics Education Association
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• v.19 no.1 s.43
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• pp.149-162
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• 2007

Fashion industry that is apparel of the latest textile industry become the center and it is universal inclination that addend value of design is high more and our country apparel industry is accelerating change by life culture industry of the high added value center. Differentiation of goods, high added value anger can be required by activation of professional manpower for strengthening competitiveness of domestic apparel field, and it is design to be texture another thing can raise this. Specific education to train able member of society based on these actual conditions grasping society actual conditions in present age that is specialized and diversifies and atomizes should be achieved. Hereupon, we have researched over current education status about domestic textile related courses and come to a conclusion described below. Domestic textile related courses are offering mostly in weaving and staining as major subjects, therefore distinguished character of each university can not be found. However, in comparison of importance between theoretical courses and practical courses, theoretical courses are gradually considered more importantly And the number of courses about commodity and operation is steadily increasing compared to those of design element. Nevertheless, for the concept of creativity as design education ever been pursuing by experiment and practice, we are also required to keep close relationship with industry as well as making efforts to reduce differences between college education and practical business. In addition, textile related colleges also need to be armed with more professional knowledge in odor to provide their students not only with more job opportunities but also with chances for self-development.

• Korean Journal of Environmental Agriculture
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• v.32 no.3
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• pp.207-213
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• 2013

BACKGROUND: This study was conducted to develop analytical method with reproducibility, accuracy and applicability to agricultural products than the existing methods. METHODS AND RESULTS: Mean recoveries of thidiazuron ranged from 89.2 to 91.2 in hulled rices, 87.2 to 92.1 in peppers, from 76.4 to 86.9 in potatoes, from 91.2 to 95.7 in watermelons, from 86.5 to 88.5 in kiwi fruits, and from 89.5 to 94.0 in grapes, with less than 10% of relative standard deviations. In addition, the limit of quantitation was set to be 0.05 mg/kg and there were no interfering peaks in integrating the thidiazuron peak. CONCLUSION(S): These results represent that the enhanced analytical method has reliable accuracy, precision, selectivity, and sensitivity.

• Economic and Environmental Geology
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• v.43 no.5
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• pp.455-466
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• 2010

Seabed mineral resources explored by Korea are categorized into major three types of deposit; manganese nodule, manganese crust and polymetallic sulfides. Pt displays high enrichment factors (400, ore/crust ratios) in manganese nodule. Rare earth oxide content in manganese nodule ranges from 0.037 to 0.302 REO % with mean value of 0.12 REO %. Both of Te and Pt are enriched elements in manganese crust, displaying enrichment factors of 10800 and 150, respectively. Rare earth oxide's contents of manganese crust are slightly higher than manganese nodule's (0.013~0.387 REO %, average = 0.18 REO %). Se and In are outstanding rare metals from seabed polymetallic sulfides, showing enrichment factors of 1300 and 110, respectively. Au (0.8~26.3 g/t) and Ag (0.9~348.0 g/t) are another enriched elements in polymetallic sulfides. The main concern at exploiting seabed mineral resource will be a securing rare metals for high-technology industries and rare metals from subsea mineral deposits will add economic values to commodity candidates such like Co, Ni and Cu.

• Archives of design research
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• v.11 no.2
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• pp.203-213
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• 1998

The forthcoming twenty-first century is at the mercy of information and culture. A quality of humanlife is under the control of a cultural level. A nation's creative culture and a cultural level represent all things about the nation; and a national image, as a whole result of culture, is enormously influential. This new era of culturalism gives us a significant responsibility for getting ready for the late industrial society by practically harmonizing rationality of modem culture with conception of traditional culture. Industrializing culture and culturalizing industry will be the most important strategy for existence in these days of borderless international competitiveness. Cultural products which is containing a nation's own culture can not only enhance the national image, but also become high value-added industry. While general products are developed for the purpose of convenient and practical use, cultural products are created with the intention of informing international society about a nation or a region. In order to confront with a global market system and a change of cultural environment, it is necessary to create a proper design with cultural inheritance for modem likes and senses, to produce the design on a commercial scale, and to strengthen its competitiveness on international markets. In order that a commodity is born, distributed throughout markets, and delivered to a final consumer, it is essential to understand complicated process such as development, distribution and marketing of products and to systematize each part. Although we should not neglect any part, a political and systemical plan or a distributional and marketing idea will be beside the point in this article. This article presents importance of traditional patterns as a Korean cultural image, and it shows the process of designing and developing products in order for traditional patterns to be utilized for products effectively. I expect that concrete activation and systematization for those works can be carried out successively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.149-155
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• 2020

Cattle feeding in South Korea has been heavily dependent on domestically produced rice straw and imported grain. Around 42% of domestically produced rice straw is utilized for forage, and the remainder is recycled to restore soil fertility. Approximately 35% of round baleages were made with rice straw. However, higher quality hay is desired over rice straw. Due to increasing stockpiles of rice, there has been an economic burden on the government to store the surplus; therefore production of annual forage crops in rice fields has been further promoted in recent years. Hay import from the USA currently constitutes more than 80% of total imported hays. The main imported hays are alfalfa (Medicago sativa), timothy (Phleum pretense), and tall fescue (Festica arundinacea). The estimated forage required for cattle feeding was approximately 5.4 million MT in 2016. Domestically produced forage sates only 43% of that value, while low quality rice straw and imported hay covered the rest of demand by 33% and 20%, respectively. As utilization of domestically produced forage is more desirable for forage-based cattle production, long-term strategies have been necessary to promote domestic production of high quality baleage. One such strategy has been utilizing the fertile soil and abundance of fallow rice fields of western region of S. Korea to produce forage crops. Italian ryegrass (Lolium multiflorum) is the most successfully produced winter annual in the region and is approximately 56% of the total winter annual forage production. Forage sorghums (Sorghum bicolor), sorghum × sudangrass hybrids, and hybrid corn (Zea mays) produce a substantial amount of warm-season forage during summer. Produced forage has been largely stored through baleage due to heavy dew and frequent rains and has been evaluated according to S. Korea's newly implemented baleage commodity evaluation system. The system weighs 50% of its total grading points on moisture content because of its importance in deliverable DM content and desirable baleage fermentation; this has proved to be an effective method. Although further improvement is required for the future of forage production in South Korea, the current government-led forage production in rice fields has been able to alleviate some of the country's shortage for quality hay.