• The KIPS Transactions:PartC
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• v.9C no.1
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• pp.97-106
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• 2002

In 3GPP2 standard, MIP is used and a PDSN performs the function of FA to support macro mobility. When a MS is roaming from a PDSN area to another, the mobility supported is called macro mobility, while it is called micro mobility when a MS is roaming from a RN area to another in a PDSN area. Since a PDSN performs the function of FA in 3GPP2 standard, it is possible to support mobility but its mechanism is actually for supporting macro mobility, not for micro mobility, thus it is weak in processing fast and seamless handoff to support micro mobility. In this paper, we suggest the seamless handoff algorithm barred on multicast group mechanism to support micro mobility. Depending on the moving direction and velocity of a MS, the suggested algorithm constructs a multicast group of RNs on the forecasted MS's moving path, and maximally delays RNs'joining to a multicast group to increase the network efficiency. Moreover, to resolve the buffer overhead problem of the existent multicast scheme, the algorithm suggests that each RN buffers data only after the forecasted handoff time. To prove deadlock freeness and liveness of the algorithm. we use state transition diagrams, a Petri-net modeling and its reachability tree. Then, we evaluate the performance by simulation.

• Journal of Mushroom
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• v.20 no.2
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• pp.61-68
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• 2022

We investigated the standard cultivation substrate for Sparassis latifolia "Neowul" bred in Jeollabuk-do Agricultural Research and Extension Services. Cultivation characteristics and yield were assessed by varying the kind of sawdust and additives, and the mixing ratio. The cultivation period in larch sawdust was the shortest at 97 days. The yield was excellent (143.6 g). The findings indicated that larch is a tree species appropriate for the cultivation of S. latifolia. When the additives were varied, the yield and productivity (53.1%) were highest (116.6 g) for the wheat bran treatment. Thus, wheat bran would be an additive appropriate for culturing S. latifolia. Concerning the use of different mixing ratios, larch sawdust:beet-pulp:wheat bran ratios of 80:15:5 and 85:10:5 resulted in yields of 114.4 g and 111.4 g, and productivity of 52.5% and 51.8%, respectively. These yield and productivity values were not statistically different. Thus, the standard cultivation substrate for S. latifolia can comprise larch sawdust, beet pulp, and wheat bran at a ratio of 80:15:5 or 85:10:5. The carbon/nitrogen (C/N) ratio assumed to be appropriate for the cultivation of S. latifolia was 184-223. Pinheading would be difficult below a C/N substrate ratio of 105. Thus, the C/N ratio of the media, as well as the pH, would be vital factors affecting pinheading during S. latifolia cultivation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.1
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• pp.14-30
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• 2006

It is difficult to secure public lots in the downtown area, school lots can be made the best use of important source to increase the area of green land in the city. The tree-planting campaign for schools has been in force since 1999 by the city of Seoul and at present; it is currently established as the plan of school parks. Thereupon, the purpose of this study is to present some ways to revitalize elementary schools to be used as vest pocket parks through the research of elementary schools, which are subject to the plan of school parks in Seoul. The results of this study are as below : The subjects to revitalize school parks as vest pocket parks are as follows. First, the land has to be utilized for security of space. Second, in addition to the front and back gate, another passage to the park has to be set up for easy access. Third, the fence has to be formed as a hedge used outside the park. Fourth, selecting plants, species of trees suitable for the landscape of school and taking into consideration the aspect of ecology. Finally, it is urgent to enact socially and economically proper standard of law by the new standards of area for school landscape considering not only the building law and regulations of general landscape, but also specific characteristics of school landscape.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.6
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• pp.507-516
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• 2019

The investigation of land characteristics is an important task for the calculation of officially land prices and standard comparison table of land price. Therefore, it should be done objectively and consistently. However, the current investigation system is mainly done by researcher's subjective judgment. Therefore, the objectivity and consistency of this investigation is not guaranteed and questionable. In this study, we first defined the problem by analyzing the current land topography investigation method. In addition, in order to investigate the land topography, the geometry of the parcel is quantified by spatial information and applied to the decision tree based method(C4.5) to produce the final result. This study intended to extract the parcel characteristics data of the topographic by the use of spatial information and to apply the information to the C4.5, there by suggesting a method for addressing the problems. The findings showed approximately 93.5% between the results of topography classification estimated with rules learned by C4.5.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.1
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• pp.79-85
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• 2015

Three specimens of larvae (5.2~7.8 mm in standard length (SL)), of the family Scombridae, were collected from the southeastern waters off Jeju Island in August, 2014. These specimens were identified to Katsuwonus pelamis have melanophores distributed on the 1st dorsal-fin spines and post ventral margin on caudal peduncle. An analysis of the cytochrome oxidase submit I (COI) sequences (652 base pairs) of mitochondrial DNA showed that our specimens must be K. pelamis, because their sequences were concordant with those of the adult K. pelamis (genetic distance= 0.000~0.002), followed by Auxis rochei (genetic distance= 0.061~0.063) and Euthynnus affinis (genetic distance= 0.077~0.079). During the larval stage, K. pelamis differed from Thunnus spp. species in melanophores distribution period of 1st dorsal-fin spines, lower jaws and ventral margin on caudal peduncle. In conclusion, occurrence of K. pelamis larvae means Korean waters are potential spawning ground of K. pelamis.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.3
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• pp.19-27
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• 2001

Accordingly it is very important to not only develop the stack of protocol, but also try an international standardization regarding the standard protocol of VoIP. Has compared to the advanced countries having already some success in commercialization, Korea is relatively much less involved in relation to this technology and endeavors. In this regards, this paper is focused on developing a protocol stack made with encoder/decoder, the generator or the header file, syntax analyzer etc. based on the protocol grammars of Session Description Protocol supported by IETF RFC2327. For the sake of it, first describe the SDP BNF grammar based on IETF RFC2327 Augmented BNF. And then we produce the Abstract Syntax Tree, header file generator for encoding/decoding as applying the method of syntax directed to SDP protocol grammar.

• Journal of Korean Society for Quality Management
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• v.39 no.3
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• pp.391-399
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• 2011

Our study was carried out to analyze the variation factors of severity-adjusted length of stay(LOS) in coronary artery bypass graft(CABG). The subjects were 932 CABG inpatients of the Korean National Hospital Discharge In-depth Injury Survey from 2004 through 2008. The data were analyzed using $x^2$ test and the severity-adjusted model was developed using data mining technique. The results of the study were as follows: male(71.1%), older than 61 years of age(61.6%), more than 500 beds(92.8%) and admitting via ambulatory care(70.0%) appeared to have higher rate than otherwise. In-hospital mortality of CABG inpatients was 2.8%. In addition, 46.4% of the patients received their care in other residence. The angina pectoris(45.6%) was found to be the highest in principle diagnosis, followed by chronic ischemic heart disease(36.9%) and acute myocardial infarction(12.0%). We developed severity-adjusted LOS model using the variables such as gender, age and comorbidity. Comparison of adjusted values in predicted LOS revealed that there were significant variations in LOS by location of hospital, bed size, and whether patients received the care in their residences. The variations of LOS can be explained as the indirect indicator for quality variation of medical process. It is suggested that the severity-adjusted LOS model developed in this study should be utilized as a useful method for benchmarking in hospital and it is necessary that national standard clinical practice guideline should be developed.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.279-285
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• 2008

Diospyros peregrina Gurke. (Ebenaceae) is a small middle sized tree grows luxuriantly in the plains of costal West Bengal, India. The objective of the study was to explore the antidiabetic activity of methanol extract of matured fruits of Diospyros peregrina to substantiate the folklore claim of traditional practitioners. It was also aimed to establish correlation with reduction of oxidative state associated with diabetes. Methanol extract of matured fruits of Diospyros peregrina was administered orally at doses of 150 and 300 mg/kg body weight for 12 consecutive days to normal and streptozotocin induced diabetic rats. Fasting blood glucose level was estimated in both normal and diabetic rats while serum lipid profiles, liver glycogen level and pancreatic thiobarbituric acid reactive substances (TBARS) were evaluated for diabetic rats. Initial and final changes in body weight were also recorded. Oral glucose tolerance test was performed during the course of study. Experimental findings showed significant antidiabetic potential of extract in term of reduction of fasting blood glucose level of both normal and diabetic rats. It was found that extract at the dose of 300 mg/kg body weight is more effective and percentage reduction (55.64) of elevated blood glucose level is comparable to that of standard drug glibenclamide (60.60) at a dose of 10 mg/kg body weight. Observed data found statistically significant in reduction of serum lipid and pancreatic TBARS levels whilst improvement was observed in liver glycogen level and body weight profiles in extract treated diabetic rats.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.266-278
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• 2008

Erythrina stricta, a deciduous tree widely used traditionally in indigenous system of medicine for various ailments such as rheumatism, fever, leprosy, epilepsy etc. The leaves of Erythrina stricta was extracted with ethanol (70%) and used for the evaluation of various in vitro antioxidant assays which includes H - donor activity, nitric oxide scavenging, superoxide anion scavenging, reducing ability, hydroxyl radical, hydrogen peroxide scavenging, total phenolic content, total flavonoid content, total antioxidant activity by thiocyanate and phosphomolybdenum method, metal chelating, $\beta$-carotene bleaching, total peroxy radical assays. The pro-oxidant activity was measured using bleomycin-dependent DNA damage. Ex vivo models like lipid peroxidation and erythrocyte haemolysis were also used to study the antioxidant property of the extract. The various antioxidant activities were compared with suitable standard antioxidants such as ascorbic acid, butylated hydroxyl toluene, $\alpha$-tocopherol, curcumin, quercetin and Trolox. The generation of free radicals viz. $O_2^{{\cdot}-}$, $OH^{\cdot}$, $H_2O_2$, $NO^{\cdot}$ and peroxyl radicals were effectively scavenged by the ethanolic extract of Erythrina stricta. In all the methods, the extract offered strong antioxidant activity in a concentration dependent manner. The total phenolic content, flavonoid content and total antioxidant activity in Erythrina stricta were determined as microgram (g) pyrocatechol, quercetin and $\alpha$-tocopherol equivalent/mg respectively. The extract did not exhibit any prooxidant activity when compared with ascorbic acid. The results obtained in the present study clearly indicates that Erythrina stricta scavenges free radicals and reduces lipid peroxidation, ameliorating the damage imposed by oxidative stress in different disease conditions and serve as a potential source of natural antioxidant.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.115-125
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• 2020

Background: The phenomenon of tree dieback in forest ecosystems around the world, which is known to be associated with high temperatures that occur simultaneously with drought, has received much attention. Korea is experiencing a rapid rise in temperature relative to other regions. Particularly in the growth of evergreen conifers, temperature increases in winter and spring can have great influence. In recent years, there have been reports of group dieback of Pinus densiflora trees in Korea, and many studies are being conducted to identify the causes. However, research on techniques to diagnose and monitor drought stress in forest ecosystems on local and regional scales has been lacking. Results: In this study, we developed and evaluated an index to identify drought and high-temperature vulnerability in Pinus densiflora forests. We found the Drought Stress Index (DSI) that we developed to be effective in generally assessing the drought-reactive physiology of trees. During 2001-2016, in Korea, we refined the index and produced DSI data from a 1 × 1-km unit grid spanning the entire country. We found that the DSI data correlated with the event data of Pinus densiflora mass dieback compiled in this study. The average DSI value at times of occurrence of Pinus densiflora group dieback was 0.6, which was notably higher than during times of nonoccurrence. Conclusions: Our combination of the Standard Precipitation Index and growing degree days evolved and short- and long-term effects into a new index by which we found meaningful results using dieback event data. Topographical and biological factors and climate data should be considered to improve the DSI. This study serves as the first step in developing an even more robust index to monitor the vulnerability of forest ecosystems in Korea.