• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.2075-2078
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• 2002

Internet became the most popular network in spite of its weakness in realtime multimedia service. Many experts believe that the Internet has the potential to become the main multimedia distribution network of the near future. Currently, it does not provide any (BoS guarantees and, even when it does, guaranteed quality delivery of video may turn out to be too expensive. Unavoidable packet losses and delay jitter caused by congestion in a best effort delivery environment require use of intelligent transport techniques for effective video delivery. According to market needs of better quality of service (QoS) fur realtime multimedia services over Internet, they have been standardizing RSVP, IntServ, and DiffServ This paper combines the benefits of QoS mechanisms such as RSVP/IntServ with scalable video encoding. We propose that more important bit stream is given more priority such that limited network resources are guaranteed far the stream. Various prioritizing approaches are proposed and compared to normal approach by using Network Simulator. The calculated QoS parameters such as packet loss rate are used to calculate degree of degradation in video quality. In this Paper, proposed methods can be implemented adaptively to Von protocol, such as H.323, SIP.

• KSCI Review
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• v.15 no.1
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• pp.17-23
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• 2007

The change of traffic by the CDV is entered in a condensed form in UPC/NPC, overflowing the buffer of the net and possibly causing its congestion. For this reason this paper proposes the Cell Spacing Scheme. As the Cell Spaing Scheme. two method is proposed; RAT based on the time in which cells enter the spacer and RDT based on the time in which cells come out from the spacer. This Paper Proposes the improved spacing sheme in which the departure time of the present cell determines the departure time of the next one, by combining with Leaky Bucket and using the traffic characteristics of ATM network.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.4
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• pp.782-792
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• 1997

Asynchronous transfer mode (ATM) provides the means to support with variety of multimedia serivices in broadband network. For the support of multimedia services, various data traffic with priortes should be controlled errectively and congestion function is required in the network to carry out the control operation. To accomplish this in a flexible and effective manner, priorty classes for the different services are commonly used. In this paper, we suggested a buffer managment algorithm in ATM network to improve overall network performance with separated buffer which consists of existing buffer with threshold andauxiliary buffer whose input consists of superposition of voice and data traffic. To evaluate the proposed buffer managment algorithms, simulations are excuted with two proiorities and the results are provied that network throughput is improved better than the existing parital buffer method.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2003.05a
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• pp.198-205
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• 2003

The concept “Environmental Stress(ES)” can be used as a useful index when assessing the maritime traffic safety. It is composed of two parts, one due to geographical restriction and another one due to traffic congestion. In this paper, Environmental Stress due to geographical restriction is reviewed. Its characteristics are surveyed from the sample calculation results for some hypothetical cases, such as approaching a breakwater, navigating in a long straight channel, and in a long bended channel. Sample calculations are also carried out for the approach channels in Busan and Kwangyang harbor. By using this ES concept. it is expected that objective and quantitative assessment of safety is possible for various environmental conditions when navigating in a harbor or in a fairway.

• The Korea Journal of Herbology
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• v.22 no.1
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• pp.81-87
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• 2007

Objectives: Angelicae Dahuricae Radix (Baek-Ji in Korean, BJ) is well known to be used as a medicine for cold, headache, supraorbital pain, nasal congestion, and toothache. Little is understood about the roles of BJ in the cytokine and chemokine secretion by immune cells. This study was designed to find out the effects of BJ on the cytokine and chemokine secretion in human mast cells (HMC). Methods : We treated BJ according to consistency on HMC and measured cytokines and chemokines levels using flow cytometry CBA system. Results: In BJ treated group. the expression of interferon-inducible protein 10 (IP-l0), monocyte chemoattractant protein-1 (MCP-1), chemokine (C-X-C motif) ligand 9 (MIG), and interleukin 10 (IL-l0) levels were decreased significantly and chemokine (C-C motif) ligand 5 (RANTES), IL-8, $interferone-{\gamma}$ ($IFN-{\gamma}$), and tumor necrosis factor alpha (TNF-a) were decreased significantly. Conclusion : The results of this experiment supposed that the treatment of BJ will ameliorate the secreting levels of some chemokines or cytokines such as IP-10, MCP-1, MIG, IL-10, RANTES, IL-8, $IFN-{\gamma}$, and TNF-a.

• Journal of IKEEE
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• v.10 no.2 s.19
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• pp.123-127
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• 2006

An Ad-hoc network which is composed of mobile nodes only should be able to distribute the traffic load evenly to the network so that the network could utilize its resources effectively However, most of researches have been concentrated in channel establishment level, not in channel reestablishment level. In this paper, the existing AODV routing protocol has been modified and upgraded to disperse the traffic load more quickly A node which uses the modified AODV routing protocol proposed in this paper broadcasts a control message to adjacent nodes, which announces congestion around the node. In order to verify the performance improvement of the proposed protocol, simulation study has been carried out by using ns2 simulator.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.597-607
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• 2008

ATIS(Advanced Traffic Information System) provide valuable information as the travel time and traffic congestion, detour, traffic accident information to drivers, so it is being in the spotlight. But so far, the study on the consumer satisfaction with providing traffic information is incomplete. So, this study run a Canonical discriminant analysis and a Canonical correlation analysis by a QuantificationIItheory based on a Traffic Information Satisfaction image data through questionnaires, and found out the factors with influence on the consumer satisfaction. And this study definitely found out the correlation between consumer's recognition and traffic information satisfaction through understanding the change on the recognition about traffic information satisfaction by a QuantificationItheory. Finally, this study found out the change on the sensibility recognition of drivers by running the principal component anlysis, developed the traffic information satisfaction evaluation model considering the change on the recognition by using the structural equation model.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.4
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• pp.122-130
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• 1999

The main purpose of this project is to improve the funeral and grave culture which has brought about many social problems, and to fix the crematory culture as the future funeral ceremony in our country. In this study, we first investigated the actual condition of cremation culture. Second, we survey three representative crematorium as an object of study and investigated similar sample buildings in Japan, we analyzed the problem of existing crematorium. Finally, we arranged the basics to approach the space program and design criteria of this project. 1. The entrance of vehicles has been commonly concentrated to the opening time of crematorium. therefore, Peak time has come out as circulation of cremation and waiting time is increasing, also it is difficult to manage the congestion normally. 2. The whole problem of crematorium is poor environment, inferior buildings, noise, unsatisfactory ventilation and privacy, insufficient convenience facilities. 3. The user demand on the crematorium facilities is a private family room for waiting area, a farewell room for family members in a direct line, an outdoor rest area, and the various service facilities, and so on. 4. For improvement of the funeral and grave culture, it is necessary that crematorium is not a hatred facilities, as the conversion of consciousness, and to new shape of charnel as it wore family tomb.

• Korean Journal Plant Pathology
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• v.11 no.1
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• pp.1-8
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• 1995

Alternaria alternata and A. solani were identified from 130 Alternaria isolates obtained from red pepper fruits, and three species including A. alternata, A. sesami and A. sesamicola were detected from 150 isolates from sesame seeds. Among the 4 Alternaria species, A. alternata was the predominant fungus from both plants, having incidence of 95.4% in red pepper and 56.0% in sesame. Of the total 280 isolates, cultures on autoclaved rice of 75 isolates were tested for toxicity to 21-day-old virgin female rats. Out of 50 isolates of A. alternata, 17 were lethal to rats, inducing congestion and hemorrhage of stomach and intestine and kidney enlargement, and 8 caused lack of weight gain or weight loss. The other 25 isolates of A. alternat and all the isolates of A. sesami, A. sesamicola and A. solani, showed no significant indication of toxicity. Production of mycotoxins in the rice cultures of the above 75 isolates belonging to 4 species was analyzed. Alternaria cultures were extracted with methanol and purified by using solvent partition, thin-layer chromatography, and high performance liquid chromatography. Of the four species tested, all produced alternariol (AOH) and alternariol monomethyl ether (AME), three (A. alternata, A. sesami and A. sesamicola) produced alternuene (ALT) and altertoxin-I (ATX-I), and only A. alternata produced tenuazonic acid (TA). TA was produced by all of the highly toxic (lethal to rats) isolates of A. alternata, but not by any nontoxic isolates.

• Korean Journal of Environment and Ecology
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• v.22 no.2
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• pp.113-118
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• 2008

This study was carried out with the aim to provide basic data for efficient park management by analyzing satisfaction factors and estimated regression model through questionnaire survey method for the visitors to Bukhansan National Park in Korea. As a result of analysis, it was found that visitors are satisfied with such variables as 'illegal camping', 'cooking act' and 'padded bills' but extremely unsatisfied with 'waste problem', 'congestion', 'damage of visiting trails' and 'lack of cultural facilities'. In the result of satisfaction factors, it was revealed that 'facility management factor' was found to have the greatest effect on satisfaction degree. In the estimated model by Multiple Regression Analysis, 'damage of natural resources' and 'damage of cultural and historic resources', and 'lack of traffic facilities' were found to affect visitors' satisfaction.