• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.2
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• pp.13-22
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• 2017

The present study proposes a new methodology for predicting the demand for truck rest areas beside national highways. Previous demand forecasting methods were reviewed first in order to complement them with additional items. The results of the study are as follows. In the demand forecasting process, the primary task is to divide parking demands of trucks into short-term parking and long-term parking. Since short-term and long-term parking vary in utilization, congestion, and turnover rate, different influence factors should be considered according to parking time. Furthermore, the demand characteristics of rest and convenience facilities need to be reflected as well, because they in turn affect the demand for truck rest areas. In sum, the demand forecasting process for destination-type truck rest areas on national highways requires more attention than that for truck rest areas on expressways, and possible influences of various factors should be examined in this process.

• International Commerce and Information Review
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• v.14 no.1
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• pp.197-218
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• 2012

Technological competitiveness of SMEs is an important factor of the country's industrial competitiveness. And technological competitiveness of SMEs in South Korea has been a long-term congestion. Through the study, we analyzed the correlation between SMEs technical support policy and technological competitiveness. As a result, the technological competitiveness of SMEs is positively related to R&D policy of funding, taxation and infrastructure. And on the other hand, R&D support policy positively effected the technological competitiveness of subcontractors, 5~49 people of small enterprises and innovation SMEs. We suggest that technology fund should be increased by expanding policy funds, investments and loans. Also, allocation of strategic R&D resources and supportive researching staffs are needed to strengthen high-growth innovative SMEs.

• The Korean Journal of Air & Space Law and Policy
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• v.5
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• pp.303-320
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• 1993

The construction of New Seoul International Airport is under way despite much controversy. Among much discussed, but not well-formulated controversy is the possibility of the airport as a hub in the North Asia Region. This paper specifies the factors which render it possible for an airport to be a regional hub. Then each factor is applied to the new airport to see whether it can function as a hub airport. Also examined is the qualitative cost and benefit calculation related to the hub function. The usual discussion has missed one big point of cost side of hub function in the belief that the hub only produces benefits to the national economy where the airline and airport industry belong; earlier-than-expected congestion and the necessity to expand the airport sufficiently enough to accommodate the increasing air demand. An airport as a hub is determined by several factors; geographical location ; economic status of the country where the airport belongs ; bilateral air service agreements according to which the airlines can exercise the route rights; the airport charges which directly influence the cost structure of the carriers ; international aviation and airport related policies of each country in the region ; airport capacity etc. The tentative implications of this paper are the followings; first, the new airport is able to function as a regional hub in the transpacific routes which connect Asian countries and North America. That is, directional hubbing by the airlines is implicated; second, the main benefits may be accrued to american airlines exercising all the route rights in the Asian region; third, the governmental effort to make the new airport a regional hub must take caution in optimizing the hubbing level (% of transitting passengers and freight) between the benefits and the costs. Further Studies may include optimal level of hubbing for the new airport and, quantification of the impact of the new airport on the national economy depending on the degree of hubbing.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.3
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• pp.39-49
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• 2010

Ad hoc network is infrastructureless network, that the network topology is configured by each node. Each node capacity device function namely, accomplishes a network control and a function of management because not being Network device of the exclusively. Ad hoc networks what kind of node join or leave the network topology to facilitate the expansion of arbitrary topology, to the case which is the distance whose traffic is distant the place must overtake through the route of intermediate nodes, like these facts give an effect to performance fluctuation. Consequently, each node in order to maintain traffic of oneself stably there is a necessity which will consider traffic and congestion control from the node which traffic of a condition and oneself of traffic of the circumference and the route which compose the network will overtake through. This paper assumes the path of the band with a finite resource, and path traffic to occupy the competition and its impact on transmission performance of these competing arguments to configure the model factor to analyse the performance impact on the results presented. Like this result with the fact that from the study, it will contribute in network management policy and the technique.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.669-674
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• 2017

Due to the depletion of fossil fuels and the increase in environmental pollution, electric vehicles are attracting attention as next-generation transportation and are becoming popular all over the world. As the interest in electric vehicles and the penetration rate increase, studies on the charging infrastructure with vehicle-to-grid (V2G) technology and information technology are actively under way. In particular, communication with the grid network is the most important factor for stable charging and load management of electric vehicles. However, with the existing centralized infrastructure, there are problems when control-message requests increase and the charging infrastructure cannot efficiently operate due to slow response speed. In this paper, we propose a new charging infrastructure using mobile edge computing (MEC) that mitigates congestion and provides low latency by applying distributed cloud computing technology to wireless base stations. Through a performance evaluation, we confirm that the proposed charging infrastructure (with low latency) can cope with peak conditions more efficiently than the existing charging infrastructure.

• Journal of International Academy of Physical Therapy Research
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• v.5 no.2
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• pp.723-729
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• 2014

The purpose of this study is to understand the relationship between female college students' stress level and premenstrual syndrome so that it can provide baseline data on how to cope with the syndrome. The study subjects are 250 female college students in Gyungbook area. This study chose 199 appropriate subjects and collected data. As per general menstrual phases, this study investigated the age when one had her first period, regularity and duration of period, and amount of bleeding. It used a measurement tool to measure stress level and premenstrual syndrome. Most of the subjects experienced their first period before the age of 13. The menstrual period was irregular with the duration of less than 7 days. 123 subjects had normal amount of bleeding. 121 subjects were experiencing high level of stress over 2.4. The correlation between the level of stress and premenstrual syndrome factors showed significant static correlation for each factor. Especially, the correlation between digestive system and response of autonomic nervous system was .996 and negative emotion and behavioral change was .635, and negative emotion and pain was .614 which were relatively high. The regression analysis of factors of premenstrual syndrome depending on the subjects' stress level indicated that response of autonomic nervous system had the biggest effect in the low stress group while behavioral change, negative emotion, pain, decreased concentration, water congestion, response of autonomic nervous system, and skin change had the biggest effect in the high stress group with statistical significance. Based on the result, it can be said that higher premenstrual stress is closely related to the premenstrual syndrome one experiences for some female college students.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.3
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• pp.463-469
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• 2010

This research is performed to obtain positive evidences of Mori cortex, a kind of oriental medicinal herbs, in the cellular levels. The extracts of M. cortex have shown anti-inflammatory effects against cutaneous inflammation and clinical effects on pulmonary asthma and congestion in oriental medicine. Thus BV2 cells were chosen because microglia are considered as the main immunocompetent cells in the central nervous system. Lipopolysaccharide (LPS)-induced microglial activation of cultured BV2 cells and subsequent release of nitric oxide (NO) and Prostaglandin E2 (PGE2) were effectively suppressed by methylene chloride extract of Morus alba L. (MEMA). From the inflammation-mediated mRNA and protein analyses, we showed that inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin-$1{\beta}$ (IL-$1{\beta}$) and tumor necrosis alpha (TNF-${\alpha}$) induced by LPS were markedly decreased by MEMA treatment. From the observation of nuclear factor-kB (NF-${\kappa}B$) which is controlling and mediating inflammation through COX-2 and iNOS, there showed that p65, a subunit of NF-${\kappa}B$, was increased in nuclear and $I{\kappa}B$, a competitor of NF-${\kappa}B$, was recovered in cytosol after MEMA treatment. These are corresponding with results of iNOS, COX-2, IL-$1{\kappa}$ and TNF-${\alpha}$, and confirm some suppressive effect against transcriptional activation of NF-${\kappa}B$. In conclusion, the anti-inflammatory action of M. cortex against BV2 microglia cells is expected to protect nerve tissues through suppression of neuronal inflammation in various neurodegenerative diseases.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.4
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• pp.92-106
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• 2017

The adverse weather is known as a factor that interrupts traffic flow and causes traffic accidents and traffic congestion by lowering visibility of drivers. Especially, in case of fog unlike any other weather conditions, traffic accidents lead to serious accidents and the fatality of the accidents is known to be high. This paper aims to analyze uninterrupted traffic flow characteristics under foggy conditions among adverse weathers. The traffic volumes and speeds under foggy and normal conditions were analyzed. Results indicated that fog with low visibility causes the most insignificant reduction in traffic volumes. On the other hand, the reduction in the speeds due to low visibility was evident. In addition, the relationship between flow, speed, and density in fog were analyzed. Analysis results showed that the fog with less than 200m visibility had clear impact on traffic flow.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.36S no.9
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• pp.36-48
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• 1999

Controlled transfer (CT) service has been recently proposed as a new ATM transfer capability for high-speed data applications, which used a credit-based flow control. This paper investigates buffer allocation schemes for CT service and proposes an improved dynamic bugger allocation scheme. In order to improve the responsiveness to a congestion, the proposed method is considered the load factor of a link when determining the amounts of virtual connection (VC)s buffer allocation. Also, in this paper we compare the performance of the proposed method with those of the existing buffer allocation methods such as flow controlled virtual channels (FCVC) and zero queueing flow control (ZQFC) through simulation. Simulation results show tat the proposed scheme exhibits a better performance than the existing schemes in terms of throughput, fairness, queue length and link utilization.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.69-78
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• 1998

In this study, I examined the morphological influence of radiation on rats stomach tissue, the difference between NPO and CON(contrast) in the rats stomach was measured after a single irradiation to 15 Gy dose, the results follow; In histological observation; focal congestion and epithelial denudation were observed from NPO rats of a day after irradiation. Fibrosis was showed from both of NPO and CON rats of 28day after irradiation, but in it's area, NPO rats have been more wider than CON rats. In PAS reaction; secreted mucin was reacted very weakly from both of NPO and CON rats of 7 days and 14 days after irradiation, whereas CON rats of 28 days after irradiation were reacted like to control rats. On the basis of this results, we know obviously that NPO will be a factor of stomach abnomalities while hospital patients are treated with high-energy irradiation.