• The KIPS Transactions:PartC
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• v.13C no.1 s.104
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• pp.83-94
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• 2006

This paper describes ATM cell encipherment method using Rijndael Algorithm adopted as an AES(Advanced Encryption Standard) by NIST in 2001. ISO 9160 describes the requirement of physical layer data processing in encryption/decryption. For the description of ATM cell encipherment method, we implemented ATM data encipherment equipment which satisfies the requirements of ISO 9160, and verified the encipherment/decipherment processing at ATM STM-1 rate(155.52Mbps). The DES algorithm can process data in the block size of 64 bits and its key length is 64 bits, but the Rijndael algorithm can process data in the block size of 128 bits and the key length of 128, 192, or 256 bits selectively. So it is more flexible in high bit rate data processing and stronger in encription strength than DES. For tile real time encryption of high bit rate data stream. Rijndael algorithm was implemented in FPGA in this experiment. The boundary of serial UNI cell was detected by the CRC method, and in the case of user data cell the payload of 48 octets (384 bits) is converted in parallel and transferred to 3 Rijndael encipherment module in the block size of 128 bits individually. After completion of encryption, the header stored in buffer is attached to the enciphered payload and retransmitted in the format of cell. At the receiving end, the boundary of ceil is detected by the CRC method and the payload type is decided. n the payload type is the user data cell, the payload of the cell is transferred to the 3-Rijndael decryption module in the block sire of 128 bits for decryption of data. And in the case of maintenance cell, the payload is extracted without decryption processing.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.751-761
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• 2014

This study was carried out to analyze the vegetation properties, soil characteristics and ordination of Rhododendron brachycarpum population in South Korea. Rhododendron brachycarpum were mainly distributed along the Ulleungdo and Baekdudaegan of the Korean penninsula and it's population was located at an elevation of 872m to 1466m. The Rhododendron brachycarpum population was classified into Taxus cuspidata var. latifolia dominant population, Magnolia sieboldii dominant population, Thuja koraiensis dominant population and Rhododendron brachycarpum typical population. The composition of soil properties in the same areas are as follows: organic matter, total nitrogen, available phosphorous, exchangeable $K^+$, exchangeable $Ca^{2+}$, exchangeable $Mg^{2+}$ contained, and soil pH. The capacities of these chemical properties of the soil ranged from 10.45~15.28%, 0.37~0.61%, $0.21{\sim}0.35cmol^+/kg$, $0.39{\sim}2.54cmol^+/kg$, $0.17{\sim}0.50cmol^+/kg$, $18.28{\sim}22.81cmol^+/kg$ and 4.66~5.23 respectively. The results of the correlation between communities and soil conditions of vegetation of Rhododendron brachycarpum by DCCA ordination method are as follows: Taxus cuspidata var. latifolia dominant population was found in the very steep sloped area that has low percentage of total organic matter and nitrogen than other populations. Magnolia sieboldii dominant population and Thuja koraiensis dominant population was found in the steep sloped area that has high percentage of total organic matter and nitrogen than other populations. Thuja koraiensis dominant population was found in the gentle sloped area that has high percentage of altitudinal and rock exposure. Current status of Rhododendron brachycarpum is very vulnerable with a collection of herbs constantly threatening the species' survival. Thus, concrete conservation plans to protect natural habitats should be set up as soon as possible.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.253-259
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• 2018

This study set out to select a system to realize an optimal environment for strawberry cultivation greenhouses based on data about the growth and development of strawberry and its environment and to provide basic data for the research of its improved productivity. For these purposes, the investigator conducted a field survey with greenhouses for strawberry cultivation in western Gyeongnam. The findings show that farmers in their fifties and sixties accounted for the biggest part in the age groups of strawberry farmers. While those who were under 50 were accounted for approximately 67.5%, those who were 60 or older accounted for 32.5%. As for cultivation experiences, the majority of the farmers had ten years of cultivation experiences or less with some having 30 years of cultivation experiences or more. All the farmers built an arch type single span greenhouse. Those who used nutrient solutions were about 75.0%, being more than those who used soil. All of the farmers that used a nutrient solution adopted an elevated hydroponic system. The single span greenhouses were in the range of 7.5~8.5m, 1.3~1.8m and 2.5~3.5m for width, eaves, and ridge height, respectively, regardless of survey areas. The rafters interval was about 0.7~0.8m. In elevated hydroponic cultivation, the width, height, and interval of the beds were about 0.25m, 1.2m and 1.0m, respectively. As for the strawberry varieties, the domestic ones accounted for approximately 97.5% with Seolhyang being the most favorite one at about 65.0%. As for the internal environment factors of greenhouses, 38 farmers measured only temperature and relatively humidity. As for hydroponics, the farmers used a hydroponics control system. Except for the farmers that introduced a smart farm system for temperature and humidity control, approximately 85.0% controlled temperature and humidity only with a control panel for side windows and ventilation fans. As for heating and heat insulation, all of the farmers were using water curtains with many farmers using an oil or electric boiler, radiating lamp or non-woven fabric, as well, when necessary.

• Geophysics and Geophysical Exploration
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• v.10 no.4
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• pp.383-392
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• 2007

Karstic features and mining-related cavities not only lead to severe restrictions in land utilizations, but also constitute serious concern about geohazard and groundwater contamination. A microgravity survey was applied for detecting, mapping and monitoring karstic cavities in the test site at Muan prepared by KIGAM. The gravity data were collected using an AutoGrav CG-3 gravimeter at about 800 stations by 5 m interval along paddy paths. The density distribution beneath the profiles was drawn by two dimensional inversion based on the minimum support stabilizing functional, which generated better focused images of density discontinuities. We also imaged three dimensional density distribution by growing body inversion with solution from Euler deconvolution as a priori information. The density image showed that the cavities were dissolved, enlarged and connected into a cavity network system, which was supported by drill hole logs. A time-lapse microgravity was executed on the road in the test site for monitoring the change of the subsurface density distribution before and after grouting. The data were adjusted for reducing the effects due to the different condition of each survey, and inverted to density distributions. They show the change of density structure during the lapsed time, which implies the effects of grouting. This case history at the Muan test site showed that the microgravity with accuracy and precision of ${\mu}Gal$ is an effective and practical tool for detecting, mapping and monitoring the subsurface cavities.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.33-39
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• 2010

Objective: Birth sex ratio (BSR) with human IVF-ET program is an interesting subject of social and scientific issue but very little information is available in Korea. This study was performed to assess the BSR with IVF-ET and to suggest the effective factors on the BSR. Methods: The national data from 1991~2008 were obtained from governmental Statistics Korea and the delivery data of human IVF-ET program on 2007 and 2008 were provided from the Ministry for Health, Welfare and Family Affairs. The BSR were statistically analyzed according to methods of IVF and to transferred embryos from fresh or frozen-thawed cycles. Results: The BSRs of Korean populations were over 1.10 up to 2002, and then it declined and maintained to 1.06 as balance BSR on 2007 and 2008. In human IVF-ET program, the BSRs were 1.07 on 2007 and 1.06 on 2008, respectively. Conventional IVF on 2008 showed the highest BSR as 1.10, and ICSI the lowest on 2008 as 1.01. There was no significant difference of BSRs related to the methods of in vitro fertilization and the feature of transferred embryos. Conclusion: The BSR of Korea showed 1.06~1.07 as normal and balanced state on 2007 and 2008 both general populations and human IVF-ET program. To the best of our knowledge, this is the first study to evaluate the BSR of human IVF-ET in Korea. There is a need to expand the further studies for national statistics and influencing factors on the BSR with IVF-ET.

• Korean journal of applied entomology
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• v.24 no.2 s.63
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• pp.107-114
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• 1985

This experiment was performed to see the possibility if soil-borne disease in green house can be controlled by soil solarization in Korea. Thermal death profiles of propagules of some soil-borne fungi, Fusarium oxysporum f. lycopersici, Fusarium oxysporum f. niveum, Rhizoctonia salani, Sclerotinia sclerotiorum, Sclerotium rolfsii and Pythium debaryanum, were obtained under the conditions in water-suspension and in soil. Except Pythium debaryanum, all the fungal units in water-suspension that were colonized on barley grains lost a viability within 7 days in water bath at $45^{\circ}C$. When the soil in test tubes in which barley grains infected with the fungi were also buried all the fungi tested including Pythium debaryanum were completely killed within 7 days in water bath at $45^{\circ}C$. From July to August in Korea, soil temperature at depth of 5cm and 15cm within tunnel in plastic house reached $38^{\circ}C\;to\;57^{\circ}C$ and $40^{\circ}C\;to\;47^{\circ}\C$, in 1982 and 1983 respectively. Even at 15cm depth, soil temperature were kept over $43^{\circ}C$ for 12 hours a day. Adiabatic material set under ground or under mulching with the transparent polyethylene-film on the soil surface had a boostering effect for higher soil-temperature and longer duration. Fungi buried in adiabatic block of the soil in plastic house were completely killed at 15cm depth 14 days after, and at 20cm depth 21 days after soil solarization. The exposure of the pathogens to fluctuating temperature was much more effective than to constant. From the above results, soil-borne diseases may be effectively controlled by soil solarization in the closed plastic house in hot summer season in Korea.

• International Commerce and Information Review
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• v.13 no.4
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• pp.51-79
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• 2011

Korea has accomplished the establishment of the National Single Window for Paperless Trade. Since 1991, it has developed Trade Automation Service System based on EDI technology. In 2003, Korean government and private sectors jointly began to set up National Paperless Trade Service( e-Trade Service) as one of the e-government projects. In 2008, they commenced the uTradeHub Service which was equipped with Internet based e-B/L and e-Nego service systems for the first time in the world To facilitate the service Korea amended its e-Trade facilitation Act and Law by 2007. At the end of 2011, Korea historically recorded its trade volume of 1 trillion US dollars and joined '$1 trillion trade club' as the 9the member country since the country had started international trade less than five decades ago. A rolling out of the e-B/L and e-Nego service will 'ally reduce the transaction costs of trading businesses and accelerate the activation e-trade services. The purposes of the study are to examine 'e-B/L Korea' service and its facilitation strategies as well as identify obstacles to utilize the 'e-B/L Korea' service. The paper reviewed and analyzed Korea's Paperless trade system and distinctive characteristics of the 'e-B/L Korea Service. Parts of the fOWld distinctive characteristics of the Korea's e-B/L service are as follows; It is well equiped with IT and legal system. It also has more that 30,000 potential users who are already uTradeHub service users. The paper indicated several weaknesses of the current system such as global KPI issues, circulation of the electronic documents not only in the domestic market but also among economies, development of the electronic Bill of Exchange. As resolution measures, the paper recommended the introduction of mutual recognition system of PKI among trade partner counties, setting up e-trade solution for small and medium companies, and special attention to raise users' awareness of the e-B/L service.

• Journal of dental hygiene science
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• v.2 no.2
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• pp.89-94
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• 2002

The present study attempts to find the ways to efficiently manage dental caries, one of the major causes of tooth loss, and to cope with oral diseases that deteriorate oral health. For this purpose, this study seeks to obtain fundamental data needed in planning the oral health projects. The study was conducted to the first-grade elementary school students in Hwa-Seong city, Gyeonggi-do, from April 1 - 30, 2002. The result was as follows: 1) Among a total of 2,710 subjects, 598 (274 boys and 324 girls) have more than 1 permanent tooth with a caries legion whether it was treated or not. 2) The number of permanent teeth examined is 6,029, in which girls' teeth are more (3,165) than boys' (2,864). 3) Out of a total of 6,029 teeth examined, 1,106 permanent teeth (508 boys' and 598 girls') have caries legions. 4) Out of 1,106 permanent teeth with caries legions, 170 (15.4%) were treated - 67 teeth for boys (13.2%) and 103 teeth for girls (17.2%). 5) 22.1% of the children have experienced dental caries in their permanent teeth. Among them, 20.1% are boys and 24.1% are girls. 6) The rate of the permanent teeth that once had, or now have caries legions are 21.2%, among which the rate for boy's teeth is 20.1% and that for girl's teeth is 22.1%. 7) The number of the permanent teeth that had caries legions is 0.5 for all the subjects. A boy has 0.4 and a girl has 0.5 teeth with caries legions regardless of whether it was treated or not. 8) The rate of the permanent teeth with caries legions is 86.7% for overall subjects - 88.3% for boys and 85.3% for girls. 9) The rate of treated permanent teeth is 13.3% for all the subjects - 11.7% for boys and 14.7% for girls. Based on the above result, the study draws a conclusion that in order to prevent dental caries in young students and to perform an early treatment for the dental caries that already occurred an oral health office should be installed at all the elementary schools so that elementary school students don't experience a loss of time and effort for learning and suffer nutritional imbalance or disorder. Besides, the oral health education concerning the importance of dental care should be conducted to the citizens, especially to the young people, in the community as an essential project of oral health centers in the community health offices, the public medical institutions.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.498-511
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• 2012

Mountainous wetland have many species such as II grade endangered species of wild flora and fauna(Drosera rotundifolia) and environmental indicator species(Utricularia racemosa, Habenaria linearifolia, Parnassia palustris, Molinia japonica, etc.). Accordingly, the mountainous wetlands is very important. However, most mountainous wetlands will disappear by natural or artificial aridness processes. Thus, it needs to manage mountainous wetland for protecting from aridness. This study has found out the wetland status of the environmental ecology and aridness processes moreover, it has suggested ways of improving wetland conservation plan and wetland aridness management plan. According to the results of topography structure survey, Hwaeom wetland's altitude is ranged within 750~810m(87.4%), and slope is less than $10^{\circ}$. There was ideally suited mountainous wetland. However, the water supply(1.6 meters depth and 0.8 meters wide) was built on under the wetland. For that reason, there was concerned about the aridness processes by sweeping away peat layer and dropping the water level. The distribution area of hygrophyte was narrowed to 6.7% whereas, woody plants and xerophytic plants was achieved a dominant position. If it leaves the situation as it is, the mountainous wetland will be developed next succession as forest ecosystem. Therefore, in order to sustain the mountainous wetland from aridness, it is set to the base direction of conservation and management as main schemes. Moreover, we have suggested that setting the vegetation conservation and management area which considering a ecological vegetation characteristics, managing the ecotone vegetation, setting the buffer zone for protection of ecological core areas, protecting the mountainous wetland indicator species and designating the management vegetation. In conclusion, in order to sustain and maintain a soundly wetland ecosystem, it needs to several management of wetlands damage factors. 1) suppression of the excessive groundwater to basin, 2) stabilization of wetland via hydrologic storage, 3) suppression of changing and transforming wetland into forest by succession via management of xerophytic plants.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.649-657
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• 2011

This study had targeted the Manjong Junction~Hongchun interchange section of Jungang highway in order to analyze the efficiency and improvement of the highway wild-life fences. Being analyzed wild-life fence as an effective facility for the prevention of road-kill, it had founded that the wild animals did not jump over even the two layer guardrail, concrete barrier and noise barrier, fence for rock fall. For the section with high road-kill decrease effect after installing the wild-life fence, the effect was higher at wild-life fence with the height of 1.0m where the door had not been installed and the well connected points of road facility than the area with fence height of 1.5m. The road-kill decrease effect was also high at the well managed areas even if the door has not been installed. Also, road-kill had occurred by concentrating around the end of wild-life fence after installing the fence, Moreover road-kill had also occurred around the cutting section. The door of wild-life fence had higher amount of road-kill occurrence as the installation interval was closer. it was analyzed that the door management has a lot of effect on road-kill decrease. The fence for rock fall, two layer guardrail and concrete barrier having the effect of wild-life fence installed on the road would have to be installed by connecting with wild-life fences through proper facility improvement. Although the door should not be installed if possible, it should be installed as automatic door or gravity door to prevent the door from leaving the door open. An escape route has to be formed for the prompt escape away from the road for the animals entered through the ending section of the fence. The eco-corridor has to be made by restoring the soil layer of dual purpose eco-corridor forming a planting area. Also, the dead body after the accident has to be disposed to the outer section of the road immediately in order to prevent the secondary road-kill by the predator from the road-kill. The fence has to be installed as 500m or longer in both ways, in other words 1,000m or longer, from the targeted spot of minimum accident prevention while connecting up to the bridge or box culvert, etc that are next road facilities if possible to guide wild animals safely to the eco-corridor.