• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12A
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• pp.2025-2033
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• 1999

In this paper, we forecast launching time of the commercial IMT-2000 service as feb. 2001, according to expert’s opinion, and most of they forecast rapid evolution. And, we propose two different models according to two cases for competition power of price for IMT-2000 service subscriber demand forecasting. In this paper, we combine the expert’s opinion method with the growth curve model for demand forecasting for new products in order to reduce error of the demand forecasting that haven’t past references. The estimation of needed coefficients for each growth curve model is based on experts’ subjective opinions.

• Progress in Medical Physics
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• v.14 no.2
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• pp.124-130
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• 2003

Currently, as a consequence of PACS (Picture Archiving Communication System) implementation many hospitals are replacing conventional film-type interpretations of diagnostic medical images with new digital-format interpretations that can also be saved, and retrieve However, the big limitation in PACS is considered to be the lack of mobility. The purpose of this study is to determine the optimal communication packet size. This was done by considering the terms occurred in the wireless communication. After encoding medical image using JPGE2000 image compression method, This method embodied auto-error correction technique preventing the loss of packets occurred during wireless communication. A PC class server, with capabilities to load, collect data, save images, and connect with other network, was installed. Image data were compressed using JPEG2000 algorithm which supports the capability of high energy density and compression ratio, to communicate through a wireless network. Image data were also transmitted in block units coeded by JPEG2000 to prevent the loss of the packets in a wireless network. When JPGE2000 image data were decoded in a PUA (Personal Digital Assistant), it was instantaneous for a MR (Magnetic Resonance) head image of 256${\times}$256 pixels, while it took approximately 5 seconds to decode a CR (Computed Radiography) chest image of 800${\times}$790 pixels. In the transmission of the image data using a CDMA 1X module (Code-Division Multiple Access 1st Generation), 256 byte/sec was considered a stable transmission rate, but packets were lost in the intervals at the transmission rate of 1Kbyte/sec. However, even with a transmission rate above 1 Kbyte/sec, packets were not lost in wireless LAN. Current PACS are not compatible with wireless networks. because it does not have an interface between wired and wireless. Thus, the mobile JPEG2000 image viewing system was developed in order to complement mobility-a limitation in PACS. Moreover, the weak-connections of the wireless network was enhanced by re-transmitting image data within a limitations The results of this study are expected to play an interface role between the current wired-networks PACS and the mobile devices.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.1B
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• pp.49-55
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• 2002

IMT-2000 mobile system will provide many application services such as mobile internet, wireless electronics commerce applications using air interface with high data rate. These applications require high data integrity, data confidentiality, user authentication, user identity confidentiality and non-repudiation. In this study, we analyze new security threats and air interface traffic performance for IMT-2000 mobile systems. Signal traffic for network access security services requires 0.2kbps~4.5kbps with the conditions of 246~768bits/massage, 0.2~1.0 basic services/sec and the security services of the rate 0.2~1.0 times compared with basic services.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2005.10a
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• pp.100-105
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• 2005

Recently cosmetic enterprises make rapid progress try to make well-known brands to perceive an image marketing. As the result, the brand's reliability continues to grow, beyond a medium of expression in two-dimensional, but through tridimensional, on brand's image runs strategies. In a strategic point suchlike visual as a shop's image give a stimulus to customers for increase invalue in corporate image and value of commodities. In the strategy of increase in sales, it is on the rise immediate constituent to consumers. Through cosmetic brand shops, cosmetic industries are provide personalized services and cultural facilities, rather than just selling products and to help revitalization of the cosmetic markets, and the pursuit of customer-oriented segmentation strategy to make changes for the better image for the shops. Each cosmetic brand shops' image of segmentation strategy has an effect on individual organizations and designs. As of today in Korea, cosmetic brand shop's designs, start to appear in the late 2000,will try to fine segmentation strategy for strengthen shop's image and research about unique quality of cosmetic brand shops into consumer orientation space, and make the best of significant prepare on the basis of directions for cosmetic brand shop which have ability to function as cultural facilities.

• KDI Journal of Economic Policy
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• v.32 no.3
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• pp.33-69
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• 2010

This paper examines the causes of the terms of trade decline in Korea since the mid-1990s, using the decomposition methodology suggested by Baxter and Kouparitsas (2000) as well as regression analysis. The main empirical results are summarized as follows. The decomposition exercise of changes in terms of trade showed that Korea's terms of trade decline for the past decade or so is attributable to goods price effect which were driven by the rise of oil prices relative to manufactures. The decomposition of terms of trade change for 55 countries showed that terms of trade decline due to goods price effect is a phenomenon that was commonly observed for exporters of manufactures since mid-1990s. These results suggest that external factors such as China's trade expansion, rather than internal factors, are mostly responsible for the decline in terms of trade. In accordance with these results, the regression results suggest that China's trade expansion contributed to Korea's terms of trade decline, especially in 2000s, by raising the import prices of oil and raw materials and lowering the export prices of manufacturing products.

• Journal of the Korean Association of Geographic Information Studies
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• v.19 no.2
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• pp.14-26
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• 2016

This study analyzed the correlation between the standardized precipitation index(SPI) and forest fire occurrences using monthly accumulative rainfall data since 1970 and regional fire occurrence data since 1991. To understand the relationship between the SPI and forest fire occurrences, the correlations among the SPI of nine main observatory weather stations including Seoul, number of fire occurrences, and log of fire occurrences were analyzed. We analyzed the correlation of SPI with fire occurrences in the 1990s and 2000s and found that in the 1990s, the SPI of 3 months showed high correlation in Gyeonggi, Gangwon, and Chungnam, while the SPI of 6 months showed high correlation in Chungbuk, and the SPI of 12 months showed high correlation in Gyeongnam, Gyenongbuk, Jeonnam, and Jeonbuk. In the 2000s, the SPI of 6 months showed high correlation with the fire frequency in Gyeonggi, Chungnam, Chungbuk, Jeonnam, and Jeonbuk, whereas the fire frequency in western Gangwon was highly correlated with the SPI of 3 months and, in eastern Gangwon, Gyeongnam, and Gyenongbuk, with the SPI of 1 month. In the 1990s, distinct differences in the drought condition between the SPI of 3 months and 12 months in the northern and southern regions of Korean Peninsula were found, whereas the differences in both the SPI of 1 month and 6 months were found in the Baekdudaegan region except western Gangwon since the 2000s. Therefore, this study suggests that we can develop a model to predict forest fire occurrences by applying the SPI of 1-month and 6-month data in the future.

• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.319-324
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• 2014

An 8 weeks feeding trial was carried out to evaluate the effects of dietary microbial phytase (P) supplementation on nutrient digestibility, and body composition in juvenile olive flounder Paralichthys olivaceus fed soybean meal-based diets. Seven experimental diets were formulated to be isonitrogenous and isocaloric to contain 50.0% crude protein (CP) and 16.7 kJ of available energy/g with or without dietary phytase supplementation. White fish meal (FM) provided 92.4% of the total protein in the basal diet ($S_0$), in the other 6 diets, 30% or 40% FM protein was replaced by soybean meal: 70% FM + 30% soybean meal ($S_{30}$); 70% FM + 30% SM + 1000 U phytase/kg diet ($S_{30}P_{1000}$); 70% FM + 30% SM + 2000 U phytase/kg diet ($S_{30}P_{2000}$); 60% FM + 40% SM ($S_{40}$); 60% FM + 40% SM + 1000 U phytase/kg diet ($S_{40}P_{1000}$); and 60% FM + 40% SM + 2000 U phytase/kg diet ($S_{40}P_{2000}$). After two weeks of the conditioning period, triplicate groups of 25 fish initially averaging $6.15{\pm}0.04g$ ($mean{\pm}S.D.$) were randomly distributed into the aquarium and were fed one of the experimental diets for 8 weeks. After feeding trial, supplementation of phytase significantly improved the apparent digestibility coefficients of phosphorus in flounder diets (P<0.05) containing 30% and 40% soybean meal regardless the levels. However, phytase had no significant influence on growth performance and whole body composition of fish. Based on the experimental results, we conclude that dietary supplementation of phytase could improve the apparent digestibility coefficient of phosphorus in olive flounder.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.6
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• pp.1060-1067
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• 2004

In a CDMA system, the rapacity is variable and mainly depends on multiple access interference. The multiple access interference has a deep relationship with transmitted or received power. The capacity of CDMA2000 1x system is considered to be limited by the forward link capacity. In this paper, we show that the transmitted power can represent the total cell load and we propose a load control scheme for CDMA2000 1x system. CDMA2000 1x system has fast power control scheme and we can measure forward link cell load by using total transmitted power. In the proposed algorithm, by monitoring the total transmit power, we can simply adjust data rate to channel conditions and efficiently use radio resources. The proposed algorithm is practical algorithm to implement in the power controlled CDMA systems and enhances the system throughput and quality of service(QoS)

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.9B
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• pp.771-777
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• 2004

In a COMA system, the capacity is variable and mainly depends on multiple access interference. The multiple access interference has a deep relationship with transmitted or received power. The capacity of COMA2000 system is considered to be limited by the forward link capacity. In this paper, we show that the forward link cell load can be represented by the total transmitted power of base station and we propose a forward link call admission control (CAC) strategy for COMA2000 system. The proposed call admission scheme adopts the rate control algorithm for data call. This call admission scheme enables the system to utilize radio resource dynamically by controlling data rate according to the cell load status, and enhance the system throughput and grade of service (GoS). quality of service(QoS) such as blocking and outage probability.

• Journal of Korea Multimedia Society
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• v.4 no.6
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• pp.562-569
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• 2001

IMT-2000 mobile system will provide many application services such as mobile internet, wireless electronics commerce applications using air interface with high data rate. These applications require high data integrity, data confidentiality, user authentication, user identity confidentiality and non-repudiation. In this study, we analyze air interface performance for network access security services in IMT-2000 mobile systems. Signal traffic for network access security services requires 0.2kbps ∼ 4.5kbps with the conditions of 246∼768bits/message, 0.2 ∼ 1.0 basic service/sec and the security services of the rate of 0.2∼ 1.0 times compared with basic services.