• The KIPS Transactions:PartC
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• v.15C no.5
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• pp.399-408
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• 2008

Mobile WiMAX provides wireless broadband services for data communication based on IP protocol. The limitation of physical bandwidth in the radio links may cause performance degradation in providing wireless broadband services in WIMAX. To enhance the efficiency of the radio link utilization, Payload Header Suppression (PHS) is defined as an optional header compression mechanism for mobile WiMAX. It has, however, a very limited compression capability since it has very restrictive compression fields. In this paper, hence, we assumed the application of Robust Header Compression (ROHC), a header compression scheme proposed for links characterized by high bit error ratios, long round-trip times (RTT), and scarce resource, to Mobile WiMAX, and studied its performance. Previous studies on ROHC performance merely focused on the impact of high bit error rate. However, bit error is virtually transparent to ROHC in the wireless systems like WiMAX, since the MAC provides the bit error checking function. In order to evaluate the performance of ROHC in the Mobile WiMAX environments, therefore, we evaluated the performance of ROHC with respect to the packet losses instead of bit error. We investigated the impact of the ROHC parameters that are recommended for the implementation in the ROHC and compared the performance of ROHC with PHS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.2 no.4
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• pp.545-551
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• 1998

The Radio communication by existing SSB, VHF, etc. in a coast station and a base station for military affairs is still used to a very important the device of information delivery or transmitting and receiving by the remote controller to using to the exclusive cable for a equipment established at a long distance. When a number of consumer to connected and operated by a number of transceiver is essential for a circuit controller of ICS, in KOREA, is devoted by import to considerable quantity because of to be delayed development of this field. This Paper has been realized to optimal algorithm and designing of a circuit connection controller by multi-processor to pre-stage for the development of ICS. The H/W is composed able to remote control to circuit connector with the several slave processor and a processor for master, and this has taken possible through without any obstacle to communication circuits of a control signal by FSK system. The S/W make possible monitoring for communication condition of other circuits by means of a serial communication system by the multi-processing. This paper has been studied for connecting to a circuits wished to rapidly and precisely by the full application to a interrupt technique. A technique to control by remote to a number of transceiver is a way increasing to application for a frequency resource of the limited MF/SF, VHF and the existing radio communication technique. According to, this paper will achieve to be the reduction of energy & equipment and multiplicity of information delivery in the general communication and disposal to rapid and exact for the important communication as distress, urgency and safety on the sea.

• Journal of Korea Port Economic Association
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• v.24 no.2
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• pp.175-192
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• 2008

Today's individual firms no longer compete as solely autonomous entities, but rather as supply chain. As such the competitive position of a port is not only determined by its internal strengths but also it is also affected by its links in a global supply chin. In other words, port competitiveness is becoming increasingly dependent on external coordination and control of the whole supply chain. The main purpose of this paper is to examine how a port embeds itself into supply chain in order to strengthen its competitive position by focusing on Dubai port case. This paper found that Dubai port used three phases-insertion, integration and dominance-as a strategies for how it can embedded into global supply chain successfully. Dubai's global supply chain strategies give some implications for the further development of the Port of Gwangyang. First, the Port of Gwangyang should fully utilize symbiotic relationship with Gwangyang free Economic Zone. Second, the integration between Korea Container Terminal Authority and GYFEZ can be recommended for fast decision-making and providing a one-stop-service. Finally, Gwangyang should pursue an aggressive supply chain strategy, aims at dominance in the regional port network through port alliance with small and medium ports in neighboring area.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.3 no.3
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• pp.22-30
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• 2010

3D TV was been able to see in the market in early in this year. Tablet PC such as ipad by Apple and Galaxytab by Samsung were introduced recently. Those are possible by developing H/W and S/W of computer technology. The needs of interactive contents in many areas including education and entertainment area are increasing rapidly according to the various information devices are or will be in the market. Fore the more, GoogleTV and AppleTV are compete each other to dominate the world market in advance recently. CookTV tries to dominate in the domestic market by upgrading the current system. Diverse information devices are in the market means various size of displayers are able to be shown in our life. As TV is fused to computer, the displayer is substituted to TV's screen and the trend of TV is became bigger. The evolved TV is able to replace the computer by connecting to the network and people want to do interactions with contents by using the bidirectional communication. Therefore, it is expected to changing the human lifestyle. It is natural that contents for all members of family are needed, since TV's screen become bigger. It is required that the contents should guarantees the accessability of information to the all of family members and the easy interaction with contents. Our goal of experiment are to analyse the influence of interaction with contents as the size of images and to analyse a learning effect of contents quantitatively by applying a statistical method. Users interacted with contents without any difficulty when they met a same dimension and shape of objects as ame dimension and shape objects in their experiences or learning, was confirmed. And the learning effect were analysed and explained by applying the correlation.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.175-181
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• 2014

This study was conducted to evaluate stand density-specific and generalized allometric equations, and biomass expansion factors (BEFs) for two stand densities (high density of 47-year-old: $667tree{\cdot}ha^{-1}$; low density of 49-year-old: $267tree{\cdot}ha^{-1}$) of Cryptomeria japonica plantations in Namhae-gun, located in the southern Korea. Biomass in each tree component, i.e. foliage, branch, and stem, was quantified by destructive tree harvesting. Allometric regression equations of each tree component were significant (P<0.05) with diameter at breast height (DBH) accounting for 80-96% of the variation except for branch biomass in high density or foliage and cone biomass in low density. Generalized allometric equations can be used to estimate the biomass of C. japonica plantations because the slopes of allometric equations were not significantly different by the stand density. The biomass expansion factors (BEFs) were significantly lower in the high stand density (1.33) than in the low stand density (1.50). The results indicate that BEFs were affected by different stand density, while allometric equations were little related to the stand density.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.287-298
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• 2014

This paper aims to analyze the satisfaction level of people for the different types of tree burial sites, in order to suggest directions for the policy to revitalize tree burials. For the purpose of this study, the tree burial sites were classified into four types, and we conducted a questionnaire, targeting 414 visitors to the different case sites. Through the comparative analysis among the case sites, this study found that people prefer the public tree burial sites to the private ones, and most people liked the type of tree burials best created in a natural forest among the public sites. Based on these results, this study suggested that the policy should be focused on the revitalization of public tree burial sites created especially in natural forests in order to satisfy the preference of people. Through the analysis of the questions regarding the general citizens' awareness of tree burials, this study found the improvement measures are required for convenience facilities, low satisfaction for usage charge, low credibility for private tree burial sites, and strong demands to create stable growth environment for memorial trees. On the other hand, this study confound the bright prospect for the spread of tree burials because people who have used tree burial sites were highly willingness to recommend tree burial sites to others and they wanted to do a tree burial for their own funerals.

• Journal of Korean Society of Rural Planning
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• v.22 no.3
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• pp.49-61
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• 2016

This study examined the effectiveness of and satisfaction of visitors with the Environmental Improvement Project on national parks' trail entry areas. A survey was conducted to improve the proposal framework based on the data. Data for the study were obtained from 6400 respondents who used 28 national park offices at 32 national park trail entry areas. The field research was collected in 3200 surveys, divided between pre- and post-implementation of the Environmental Improvement Project. The study variables consisted of socio-demographics, visitors' perceptions on the environmental improvement of trail entries, effects of the environmental improvement, and visitor satisfaction. Several important results were found. First, the environment of trail entries has a significant impact on the formation of images and user satisfaction of national parks. Second, the influence of the trail entry improvement showed that 71.8% of visitors rated the trail entry as environmentally friendly after the Environmental Improvement Project, compared to 48.5% of visitors rated the trail entry as environmentally friendly before the Environmental Improvement Project. The findings indicated that a top priority of environmental improvement of the trail entries needs to be the installation of convenience facilities such as rest areas, restrooms, and direction boards (pre: 34.5%, post: 32.6%). Third, functionality and the other nine variables were shown to enhance the effect of the environmental improvement of the trail entries at the 1% statistical significance level. Finally, results indicated that the overall satisfaction of the visitors with the park was significantly higher after the environmental improvement (t-value=25.741, p=.000), showing the satisfaction score was higher after the environmental improvement (pre: 3.51, post: 4.12), with a statistically significant difference at the 1 % level. This study helps to understand trail entries, which have influenced the image of the national park and satisfaction. These findings can be utilized to manage and design a national park as a public space.

• Journal of Mushroom
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• v.14 no.4
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• pp.211-214
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• 2016

Geoni, a new variety of Auricularia polytricha, was bred in JARES(Jeollanamdo Agricultural Research and Extension Services) in 2012. Geoni was selected through the monospore hybridization with JNM21008 and JNM21014 in 2010. Based on a performance test conducted from 2011 to 2012, the Geoni was selected from a line showing an excellent light brown pileus and strong pest resistance. Geoni has a favorable chewiness, light brown and smooth pileus. In addition, Geoni was rich in dietary fiber. MCM(mushroom complete medium), Malt and PDA(Potato Dextrose Agar) mediums were suitable for cultivating the Geoni. The number of effective stipes was 39 ea/0.9 kg and minor axis and major axis of pileus were 6.9 cm and 8.7 cm respectively. The yield of Geoni was 291 g/0.9 kg in plastic bag. Geoni was required 40~54 days for culture at $20^{\circ}C$ and 24days for the primordia and growth period, which is longer than that of the control(Pung-un). Somatic incompatibility was formed between parental strains and Geoni. Analysis of the genetic diversity of the new variety "Geoni"revealed a different profile from the parental strains when RAPD(random Amplified Polymorphic DNA) primers were used.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.142-150
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• 2020

This experiment was conducted to set ideal harvest time for itallian ryegrass (IRG) seed in reclaimed land. For IRG 'Kowinearly' variety sown in both autumn and spring, the peak growth in reclaimed land occurred in 20-30 days after heading. Plant height of IRG seedings in the spring was 90.4% of the fall-sown's plants. The yield of IRG seeds in reclaimed land was generally lower than that of farm land due to poor growth conditions. After heading, the lodging and shattering increased gradually with time. The highest yield of seed in the fall-sown trial treatment was 238 kg/10a. However, in the spring-sown treatment, the highest yield reached 169 kg/10a, which was 71% that of the fall-sown treatment. To set optimum harvesting time for IRG seed, morphological changes in the plant, moisture content of seed, and germination rate were analyzed according to time series after heading. After heading, IRG stem color had turned pink in 18 days and seed color also changed after 20 days. Following 20-25 days after heading, the seed moisture content decreased to below 55% and germination rate increased to over 90%. Therefore optimum harvesting time for IRG 'Kowinearly' variety in reclaimed land was 20-30 days after heading because germination rate and yields were high and shattering percentage was low.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.1
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• pp.13-21
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• 2011

To characterize the site specific properties of a study area for high-level radioactive waste disposal research in KAERI, the several geological investigations such as surface geological surveys and borehole drillings were carried out since 1997. Especially, KURT (KAERI Underground Research Tunnel) was constructed to understand the further study of geological environments in 2006. As a result, the first geological model of a study area was constructed by using the results of geological investigation. The objective of this research is to construct a hydrogeological model around KURT area on the basis of the geological model. Hydrogeological data which were obtained from in-situ hydraulic tests in the 9 boreholes were estimated to accomplish the objective. And, the hydrogeological properties of the 4 geological elements in the geological model, which were the subsurface weathering zone, the log angle fracture zone, the fracture zones and the bedrock were suggested. The hydrogeological model suggested in this study will be used as input parameters to carry out the groundwater flow modeling as a next step of the site characterization around KURT area.