• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.12
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• pp.2811-2817
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• 2010

In this paper we propose the QAC-MAC that supports Quality of Service(QoS) and saves energy resources of the sensor node, and hence prolonging the lifetime of the sensor network with multiple sink nodes. Generally, the nodes nearest to the sink node often experience heavy congestion since all data is forwarded toward the sink through those nodes. So this critically effects on the delay-constraint data traffics. QAC-MAC uses a hybrid mechanism that adapts scheduled scheme for medium access and scheduling and unscheduled scheme based on TDMA for no data collision transmission. Generally speaking, characteristics of the real-time traffic with higher priority tends to be bursty and has same destination. QAC-MAC adapts cross-layer concept to rearrange the data transmission order in each sensor node's queue, saves energy consumption by allowing few nodes in data transmission, and prolongs the network lifetime.

• Korean Journal of Plant Resources
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• v.28 no.1
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• pp.1-8
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• 2015

In order to verify the effects of Dioscorea Rhizoma on gastrointestinal damages, we investigated the protective role of the crude extracts on induced gastric ulceration in rats. Rats administered of Dioscorea Rhizoma extracts showed gradually decreased congestion and hemorrhage, but control group did not show any symptom in gastric tissue. Moreover, Dioscorea Rhizoma extract had a role in lowering gastrin and histamine levels in gastric ulcer rats, thereby inhibiting the gastric tissue damages. Excessive production of malondialdehyde shown in gastric ulcer rats was declined in all rats administered with Dioscorea Rhizoma extract as well as the levels of SOD and GPX surged by acute gastric ulcer. Also, the increased activity of CAT showed an effect in activation of antioxidant enzyme to normal state. All data suggest that Dioscorea Rhizoma extract was verified to be highly effective resource in improving the gastrointestinal function of rats by preventing from gastric tissue damage in acute gastric ulcer and restoring the activities of plasma substances and antioxidant enzymes.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.2
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• pp.36-47
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• 2020

The objective of this study is to analyze the effect of the shoulder-use lane, which is a representative traffic management technique that increases the road capacity. The operation of the shoulder-use lane has been actively used as a countermeasure to improve traffic congestion, because it has the effect of improving traffic flow during rush hour. In Korea, the shoulder-use lanes are available at Gyeongbu, Yeongdong, and on the Seoul Outer Ring expressway, and their use is gradually increasing. Therefore, a comprehensive analysis was conducted to analyze the effects of the shoulder-use lane; including 1) analysis of individual shoulder lanes based on a time space diagram, and 2) analysis of shoulder lanes by road axis. These findings can contribute to the efficient installation and operation of shoulder-use lanes on expressways.

• The Journal of Korean Academy of Prosthodontics
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• v.16 no.1
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• pp.7-11
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• 1978

The author attempted to observe the histological changes of the periodontal structures induced by trauma from occlusion. Eighteen healthy rabbits were devided into two groups; control and experimental group. Three rabbits were kept as control group, while metal crowns were seated on unilateral lower molar teeth of fifteen rabbits were kept as experimental group. And the interocc1usal distance of the incisal edge was kept 1.5mm from begining to the end of the experimental period. Rabbits of each group consisting with three rabbits were killed at the intervals of three days, one week, two weeks, four weeks, eight weeks. The antagonistic teeth of maxilla including periodontal teeth were excised and decalcified for histologic preparation. The results obtained were as follows. 1. Destructions and ulcer formation of the sulcular epithelium and gingival epithelium occurred and persisted from the beginning of the experiment to the four weeks after experiment. The epithelal attachment were proliferated apically. 2. The pressure site were observed at the apical protion, where they showed compression of the periodontal ligament, thrombosis and congestion of blood vessels and hemorrhages. 3. At the pressure site, there appeared osteoclasts and bone resorption from the first week of experiment and it became more prominent at the second week with the extend into the marrow spaces adjacent to the periodontal membrane. 4. The phenomenon of bone apposition and resorption occurred at the fourth week of experiment. The reverse line of bone trabecular were more prominent. And the reactions were ceased at the eighth week of experiment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12B
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• pp.1083-1096
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• 2008

This paper proposes an energy-aware path management scheme, so-called the TBP(Threshold based Back-Pressure) algorithm, which is designed for lifetime extension of the energy-constrained wireless sensor networks. With the goal of fair energy consumptions, we extensively utilize the available paths between the source and the sink nodes. The traffic distribution feature of the TBP algorithm operates in two scales; the local and the whole routing area. The threshold and the back-pressure signal are introduced for implementing those operations. It is noticeable that the TBP algorithm maintains the scalability by defining both the threshold and the back-pressure signal to have their meanings locally confined to one hop only. Throughout several experiments, we observe that the TBP algorithm enhances the network-wide energy distribution. which implies the extension of the network lifetime. Additionally, both the delay and the throughput outcomes show remarkable improvements. This shows that the energy-aware path control scheme holds the effects of the congestion control.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.84-92
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• 2006

Freeway Corridors consist of urban freeways and parallel arterials that drivers can use alternatively. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve traffic conditions of freeway corridors. However, most of the existing studies have focused on either optimal ramp metering in freeways, or progression signal strategies between arterial intersections. There have been no traffic control systems in Korea that integrates the freeway ramp metering and arterial signal control. The effective control strategies for freeway operations may cause negative effects on arterial traffic. On the other hand, traffic congestion and bottleneck phenomenon of arterials due to the increasing peak-hour travel demand and ineffective signal operation may generate an accessibility problem to freeway ramps. Thus, the main function of the freeway which is the through-traffic process has not been successful. The purpose of this study is to develop an integrated control model that connects freeway ramp metering systems and signal control systems in arterial intersections. And Optimization of integrated control model which consists of ramp metering and signal control is another purpose. Optimization results are verified by comparison with the results from MATDYMO.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.1
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• pp.8-15
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• 2007

Freeway corridors consist of urban freeways and parallel arterials that drivers can use alternatively. Ramp metering in freeways and signal control in arterials are contemporary traffic control methods that have been developed and applied in order to improve traffic conditions of freeway corridors. However, most of the existing studies have focused on either optimal ramp metering in freeways, or progression signal strategies between arterial intersections. There have been no traffic control systems in Korea that integrates the freeway ramp metering and arterial signal control. The effective control strategies for freeway operations may cause negative effects on arterial traffic. On the other hand, traffic congestion and bottleneck phenomenon of arterials due to the increasing peak-hour travel demand and ineffective signal operation may generate an accessibility problem to freeway ramps. Thus, the main function of the freeway which is the through-traffic process has not been successful. The purpose of this study is to develop an integrated control model that connects freeway ramp metering systems and signal control systems in arterial intersections. And Optimization of integrated control model which consists of ramp metering and signal control is another purpose. The design of experiment, neural network, and simulated annealing are used for optimization.

• Korean Journal of Pharmacognosy
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• v.43 no.1
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• pp.66-71
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• 2012

Cirsium japonicum var. ussuriense is often used in treatment of human disease such as hemorrhage, blood congestion and inflammation. This study was accomplished to evaluate the antioxidant properties of the leaf (CLE) and flower (CFE) extracts of C. japonicum var. ussuriense to protect normal human red blood cells (RBC) and plasma samples against oxidative damage in vitro. CLE and CFE were prepared by extracting with hot water. In red blood cells and plasma, oxidative hemolysis and lipid peroxidation induced by the aqueous peroxyl radical generator [2,2'-azobis (2-amidinopropane) dihydrochloride, AAPH] were significantly suppressed by CLE or CFE in a dose-dependent manner at the same time. CLE and CFE also prevented the depletion of cytosolic antioxidant glutathione (GSH) in RBC. These results suggest that the leaves and flowers of C. japonicum var. ussuriense may have the antioxidant properties.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.1
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• pp.65-68
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• 2006

It was examined the effect of fermented rice wine using mycelium of Phellinus linteus (FWPL) on the gastric mucosa of rat. The gastric mucosal lesions were not seen macroscopically in normal, but ethanol-administrated rats produced congestion and edema with a few local lesions. The administration of FWPL showed a similar pattern as like normal except trace histopathological changes. The results of Western blot analyses showed that the higher expression of inducible nitric oxygenase (iNOS), cyclooxygenase (COX)-1, COX-2, tumor necrosis factor-$\alpha$ and c-fos, especially COX-2, in the ethanol-administrated rat compared with normal rat. But FWPL-administrated rat showed a trace increase of these expression compared to normal rat. About immunohistochemical observations, weaker iNOS reactions were detected in mucous cells of epithelim of ethanol administrated rat compared with normal and FWPL-administrated rat. These results suggested that FWPL-administrated rat showed a trace changes on the mucus barrier-related protein expression compared with ethanol-administrated rat and thus FWPL may be use to develop a functional alcoholic beverage.

• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.302-310
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• 2018

To realize the self-driving technology, there have been various system designs based on the related V2X standards, especially the IEEE 802.11p and WAVE standard supporting the WLAN V2X communication. On the other hand, the new standard IEEE 802.11ba defining supplementary wake-up radio operation is now under standardization targeting the low power operation, and it includes the V2P operation in use cases. However, if IEEE 802.11ba is used with the IEEE 802.11ba for V2X operation, the additional transmission procedure of wake-up frame in IEEE 802.11ba may cause the congestion problem and fails to meet the delay requirement. In this paper, the system structure of the combination of IEEE 802.11ba with the 802.11p is studied. In addition, based on the analysis and simulation, the considerations and improvements for effective low-power V2P communication in future self-driving technology using IEEE 802.11ba are proposed.