• Journal of Korea Multimedia Society
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• v.6 no.3
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• pp.429-435
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• 2003

In this paper, we propose improved binary tree vector quantization with consideration of spatial sensitivity which is one of the human visual properties. We combine weights in consideration with the responsibility of human visual system according to changes of three primary color in blocks of images with the process of splitting nodes using eigenvector in binary tree vector quantization. Also we propose the novel quality measure of the quantization images that applies MTF(modulation transfer function) to luminance value of quantization error of color image. The test results show that the proposed method generates the quantized images with fine color and performs better than the conventional method in terms of clustering the similar regions. Also the proposed method can get less quantized level images and can reduce the resource occupied by the quantized image.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.10B
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• pp.876-890
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• 2003

This paper proposes a protocol for the reliableand QoS-aware multicast transport, which is called the Enhanced Communications Transport Protocol (ECTP). The ECTP has so far been developed and standardized in ITU-T SG17 and ISO/IEC JTC 1/SC 6. Differently from the conventional reliable multicast, as shownin the IETF RMT WG, the ECTP additionally provides several distinct features such as tight control of multicast session, tree-based error control, and QoS management. For the tight control of multicast connections, the sender is at the heart of one-to-many group communications, and it is responsible for overall connection management such as connection creation/termination, pause/resumption, and the join and leave operations. for tree-based reliability control, ECTP configures a hierarchical tree during connection creation. Error control is performed within each local group defined by a control tree, which was partly designed like the IETF TRACK approach. Each parent retransmits lost data in response to retransmission requests from its children. For QoS management, ECTP supports QoS negotiation for resource reservation, and it also provides QoS monitoring and maintenance operations. ECTP has been implemented and tested on Linux machine, along with Application Programming Interfaces based on Berkeley sockets. For basic testing of the ECTP functionality, we give some preliminary experimental results for performance comparison of ECTP and TCP unicast transports. In conclusion, we describe the status of ECTP experimentations over APAN/KOREN testbed networks

• Journal of the Korea Society of Computer and Information
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• v.14 no.3
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• pp.161-171
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• 2009

In this paper, we propose an automatic method for setting data constraints of a data cleansing service, which is for managing the quality of data exchanged between composite services based on SOA(Service-Oriented Architecture) and enables to minimize human intervention during the process. Because it is impossible to deal with all kinds of real-world data, we focus on business data (i.e. costumer order, order processing) which are frequently used in services such as CRM(Customer Relationship Management) and ERP(Enterprise Resource Planning). We first generate an extended-element vector by extending semantics of data exchanged between composite services and then build a rule-based system for setting data constraints automatically using the decision tree learning algorithm. We applied this rule-based system into the data cleansing service and showed the automation rate over 41% by learning data from multiple registered services in the field of business.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.744-749
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• 2010

Enzymatic hydrolysate from non pre-treated biomass of yellow poplar (Liriodendron tulipifera) was prepared and used as resource for bioethanol production. Fresh branch (1 year old) of yellow poplar biomass was found to be a good resource for achieving high saccharification yields and bioethanol production. Chemical composition of yellow poplar varied significantly depending upon age of tree. Cellulose content in fresh branch and log (12 years old) of yellow poplar was 44.7 and 46.7% respectively. Enzymatic hydrolysis of raw biomass was carried out with commercial enzymes. Fresh branch of yellow poplar hydrolyzed more easily than log of yellow poplar tree. After 72 h of enzyme treatment the glucose concentration from Fresh branch of yellow poplar was 1.46 g/L and for the same treatment period log of yellow poplar produced 1.23 g/L of glucose. Saccharomyces cerevisiae KCTC 7296 fermented the enzyme hydrolysate to ethanol, however ethanol production was similar (~1.4 g/L) from both fresh branch and log yellow poplar hydrolysates after 96 h.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12B
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• pp.1049-1057
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• 2006

Overlay Multicast is an effective method for efficient utilization of system resources and network bandwidth without using hardware customization. Unlike in IP multicast, multicast tree reconstruction is required when non-leaf node leaves or fails. In this paper, we propose a proactive approach to solve this defect by using a resource reservation of the out degrees. This allows children of non-leaf node to connect to its new parent node immediately when its parent node leaves or fails. In our proposal, a proactive route maintenance gives a fast recovery time and reduces a delay effect in the new route. The simulation results show that our proposal takes shorter period of time than the other algorithms to reconstruct a similar tree and that it is a more effective way to deal with a lot of nodes that have lost their parent nodes.

• Korean Journal of Plant Resources
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• v.28 no.4
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• pp.400-410
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• 2015

Juniperus chinensis (Cupressaceae) is a valuable woody plant resource, but this rare plant is only distributed in restricted regions in Korea. In this study, we surveyed the geographic distribution regions, variation of sex ratio and the dynamics of natural populations of J. chinensis. in order to establish conservation strategies for the sustainable conservation of this important resource tree. The 17 natural populations of J. chinensis are restrictively distributed in the shore cliffs of (1) Ulleungdo island, (2) Gyeongju-si to Gangneung-si of the eastern coast, the riverside cliff along (3) Donggang-river of Jungsun-gun and Pyeongchang-gun and (4) branch of Nakdonggang-river in Uiseong-gun. The populations in Ulleungdo island showed continuous population distribution of over 200 individuals, but populations in other regions had discontinuous population distribution of under 200. The population of J. chinensis surveyed in Korea was estimated in ca. 3,200 individuals. The sex ratio (male/female) among populations of J. chinensis was diverse with variation from 0.46~1.67 range, but showed no significance. The sex ratio of the total individuals by species level was 0.74, and the percentage of female tree was significantly higher than the male. The results of dynamics analysis within population among regions showed that seedlings and saplings of J. chinensis in three regions surveyed were continuously regenerating. The distribution of DBH class showed a stable population structure of inverse J shape graph, but fragmentation and decrease in populations because of invading broad-leaved shrubs and trees from the surroundings were concerned. Further studies, and in situ and ex situ conservation strategies for the sustainable conservation on natural populations of this rare resources woody plant, J. chinensis in Korea are recommended.

• Korean Journal of Food Science and Technology
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• v.46 no.5
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• pp.609-615
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• 2014

The cytoprotective effect of Moringa oleifera Lam. (drumstick tree) on neuronal cells was investigated to confirm the physiological benefits associated with this natural food resource. First, the drumstick tree extract was chemically analyzed to determine inherent nutritional constituents. Calcium and potassium were identified as the major mineral constituents, and palmitic acid (C16:0, 16.33%) and gadoleic acid (C20:01, 66.34%) were detected as the major fatty acids. Moreover, drumstick tree extract contained 94.78 mg/100 g vitamin E and 112.61 mg/100 g niacin. PC12 cells were used to study the cytoprotective effects of drumstick tree extract. Intracellular accumulation of reactive oxygen species was significantly reduced when $H_2O_2$ treated-neuronal cells were cultured in a medium containing the methanolic extract of drumstick tree, compared to cells treated with only $H_2O_2$. Cell viability assay using MTT showed that the extract protected cells against $H_2O_2$-induced neurotoxicity and inhibited LDH leakage from the cell membrane. Caspase assay showed that the extract exerted cytoprotective effect against apoptosis. Consequently, these data suggest that drumstick tree is a useful natural resource with positive effects on human health.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.4
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• pp.51-56
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• 2016

Old-growth and giant tree is a nonrenewable resource with great value. The purpose of this study is to provide scientific and reasonable evaluations for the preservation and management of the old-growth and giant tree. Until now the research of old-growth and giant tree's value evaluation and authoritative index is so insufficient and imperfection. Combining with the particularity of the old-growth and giant tree, this study analyzed the main value factors of the old-growth and giant tree and objectively selected the evaluation indicators. According to the actual situation value appraisal model of the old-growth and giant tree was builded. The main value factors can be divided into economic value, cultural history, growing place, tree state, tree form, tree vigor, protection level, growth environment, tree species, tree canopy, and so on. The evaluate indicators can be selected and the indicators' weight can be calculate using analytic hierarchy process methods(AHP). Based on economic value and indicators' weight, tree's total value can be revealed. After calculation and analysis, Gyeongju Gyerim Zelkova serrata's value evaluation results is 491,503,300 won. The research results of this study can provide scientific basis and reference to the old-growth and giant trees' value appraisal and loss compensation, and arouse people's environmental awareness.

• Journal of Forest and Environmental Science
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• v.28 no.4
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• pp.199-204
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• 2012

This study was conducted to estimate climax index by eco-morphology for major 36 tree and sub-tree species in natural deciduous forests so as to interpret seral position of each species in the forest community. Fourteen eco-morphological characters which were considered to be associated with successional gradient in the forest were selected for the study. Four levels per character for each species were given on a standardized scale of increasing climax, and the index was computed by the proportion of the sum of total scores, expressed by percent values. With calculated mean value of 54.8 for all indices, Carpinus cordata had the highest index value of 90.5, and Populus davidiana recorded the lowest of 13.2. The most climax group, greater than 70 of the index, contained only 8 species, intermediate group, between 41 to 70 of the index, had 23 species, and the most pioneer group, less than 40 of the index comprised 5 species. The result has noticed that the large number of species would take advantage of most diverse resource and niche in the intermediate stage of the sere in the forest. By cluster analysis all 36 species were subjected to be classified into several species groups which had common similar eco-morphological characteristics. The indices were additionally plotted on the two dimensional graph to recognize the positions related to the light absorption factor and reproduction factor. The climax index of tree and sub-tree species developed by this study could be applied to understand the present status of successional stage on the basis of species composition by the method of summing up the indices. And comparison of forest successional stage among various forest communities could be done by summing up the climax indices of composed species in each community. However, this kind of applied methodology should be limited to the forest of similar species composition and site condition.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.2
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• pp.234-243
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• 2000

We design a modified network architecture with condsidering current Internet network model and traffic characteristics, and propose EDCBT(Enhanced Dispersed Core-based Tree) multicast routing protocol, which enhances scalabity, reliability, end-to-end delay and resource utilization EDBCT adopts bidirectional dispersed shared trees and manages both of intradomain and interdomain multicast trees for a multicast group. Each regional multicast tree is estabilshed from its core router and they are interconnected by the operation between border routers on edges of each regional network. As a result, interdomain multicast tree can be easily established. We introduce a new concept named RBTS(Region-based Tree Switching), which dramatically enhances QoS and network utilization. Finally, protocol performance and the effect of core router location are evaluated with MIL3 OPNet network simulator, in terms of end-to-end delay, packet loss and throughput.