• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.177-186
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• 1994

Bioadhesive microcapsules of cephalexin, using Eudragit RS/RL coated with polycarbophil or carbopol, were evaluated biopharmaceutically. The GI transit of microcapsules in rats was studied. Bioadhesive microcapsules coated with polycarbophil or carbopol were shown to have substantially longer GI transit time than Eudragit RS/RL microcapsule. The delay in transit time was due to bioadhesion of the polymer to the mucin-epithelial cell surface which was clearly observable on animal autopsy. Plasma drug levels in rabbits showed that bioadhesive microcapsules resulted in a longer duration of action and greater bioavailability than other microcapsule or drug powder. Thus, the principle of bioadhesion can significantly improve therapy, due to a reduced rate of gastric emptying, an increase in contact time, and the intimacy of contact of the drug with the absorbing membrane.

• Archives of Pharmacal Research
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• v.25 no.6
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• pp.978-983
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• 2002

Small intestinal transit (SIT) has often been regarded as an index of pathophysiological state of postoperative ileus (PI) in rats. The reliability of SIT as an index of PI was examined in the present study. PI was induced via abdominal surgery (i.e., laparotomy with evisceration and manipulation) in rats. For one group of PI-induced rats, SIT of a charcoal test meal was measured. When necessary, the physical state (i.e., severity and site of distension) of the gastrointestinal (GI) tract in each rat was visually examined. For another group of PI-induced rats, abdominal X-ray radiographs were obtained after introducing the barium sulfate suspension. The abdomen was then opened and the physical state of the GI tract was visually examined. The SIT was decreased in most of the PI-induced rats, and the GI distension was observed, with substantial intersubject variations, in all of the PI-induced rats. However, no linear relationship was evident between the SIT and the severity of GI distension (e.g., at 20 h after PI induction). Instead, the severity and site of GI distension could be monitored by the X-ray radiology. Therefore, the use of SIT as an index of PI should be substantially limited.

• The Korean Journal of Nuclear Medicine
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• v.35 no.1
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• pp.1-11
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• 2001

Current scintigraphic tests of gastrointestinal motor function provides relevant pathophysiologic information, but their clinical utility is controversial. Many scintigraphic methods are developed to investigate gastrointestinal motility from oral cavity to colon. These are esophageal transit scintigraphy, oropharyngeal transit study, gastric emptying test, small bowel transit time measurement, colon transit study and gastroesopahgeal reflux scintigraphy. Scintigraphy of gastrointestinal tract is the most physiologic and noninvasive method to evaluate gastrointestinal motility disorders. Stomach emptying test is regarded as a gold standard in motility study. Gastrointestinal transit scintigraphy also has a certain role in assessment of drug effect to GI motility and changes alter therapy of motility disorders. Scintigraphy provides noninvasive and quantitative assessment of physiological transit throughout the gastrointestinal tract, and it is extremely useful for diagnosing gastrointestinal motor dysfunction. This article reviews the current procedures, indications, significance and guidelines for gastrointestinal motility measurements by scintigraphy.

• Journal of Korea Planning Association
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• v.54 no.6
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• pp.68-79
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• 2019

The purpose of this study is to propose a transit accessibility analysis method based on temporal variability of travel time. In this study, transit accessibility was defined in three levels (in transit route, spot and region unit) to present findings from different spatial scopes. Recently, Jeju special self-governing province reorganized bus system of the island. To compare transit accessibility before and after transit policy implementation, the reorganized bus system of Jeju special self-governing province was selected as a case study. This study used General Transit Feed Specification (GTFS) data format as storage public transit information, and calculated travel time using ArcGIS GTFS networks analysis tools. In the analysis of individual transit route level, we found the 3 types of accessibility changes which is increments, no significant changes and reductions and these results come from transit route change (number of transfer, distance change) rather than changes of vehicle interval. We found increases of inflow and outflow speed in most target spots and overall transit accessibility has been substantially improved in Jeju island. This study implies that accounting for temporal variability of travel time in accessibility analysis can result in more useful and sophisticated accessibility information in decision-making processes.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1495-1500
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• 2006

A signal system is critical point of transport capacity and train operation in urban rail transit. Today the moving block system by radio is taking place of the fixed block system by track circuit for efficiency and short headway in underground railway and right rail transit. In this study, assuming specification of a train, track and control system, the minimum headway on the moving block system and the fixed block system is researched for the maximum transport capacity.

• Proceedings of the KIEE Conference
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• 2007.10c
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• pp.226-228
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• 2007

The standardization system in Urban Transit is the system that verifies and develop the standard, a safety standard, a performance test standard and a Quality certification standard to improve the capability, the safety and operational efficiency and that develops technologies of the main installations. We have already developed a signal, electric power in Urban Transit. Also, we have already noticed the standardization of railroad tracks and developed the main installations through the first stage in the standardization in 1995${\sim}$2006. Still, there remains many fields to standardize, like information and communication facilities, facilities in the station, governmental organizations and maintenance facilities because, Urban Transit is so widespread. In case that we do not keep promoting the standardization in Urban Transit, rather it could hamper development of the Urban Transit. So, it is important to maintain and advance the standardization in Urban Transit. In this paper, we suggest the research course that we would promote, to maintain and develop the standardization in Urban Transit.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.729-733
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• 2007

Urban transit is a large scale complex system which combines rolling stocks, power supply, signal communications, tracks & stations. Therefore standardization is very important because it is difficult to find causes when failures or accidents occur. The standardization of urban transit increases safety and economical efficiency, and also gives passengers convenient and comfortable feeling. We, Korea Railroad Research Institute(KRRI), had finished the 1st phase study of urban transit standardization from '95 to '06. And 2nd phase study on rolling stock, information & communication, subway station has been performed from July '07. In this paper, we introduce what we study on urban transits standardization during coming 5 years. We expect our study will contribute to increase the efficiency of urban transit.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.4
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• pp.14-25
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• 2008

The Purpose of this study is to find out the renewal methods of Dae-jun railway station areas, focusing on the domestic/foreign case studies of the railway station areas and the possibility of the Industry-University-Institute collaboration in this area. As a result, this study shows that the revitalization for the impact area around rail transit station in the aspect of urban spatial structure, mixed land use, type of facilities and exchanging transit system of mass traffic etc, as well as such non-physical aspects as Industry-University-Institute collaboration and administrative planning. It does so by strengthening ties between hardware and software studies of urban planning and University Facilities planning. Finally this study suggested the strategy for the renewal of impact area around the rail transit stations.

• Journal of Neurogastroenterology and Motility
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• v.24 no.4
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• pp.669-675
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• 2018

Background/Aims Functional dyspepsia (FD) and irritable bowel syndrome (IBS) are common gastrointestinal (GI) disorders and these patients frequently overlap. Trimebutine has been known to be effective in controlling FD co-existing diarrhea-dominant IBS, however its effect on overlap syndrome (OS) patients has not been reported. Therefore, we investigated the effect of trimebutine on the model of OS in guinea pigs. Methods Male guinea pigs were used to evaluate the effects of trimebutine in corticotropin-releasing factor (CRF) induced OS model. Different doses (3, 10, and 30 mg/kg) of trimebutine were administered orally and incubated for 1 hour. The next treatment of $10{\mu}g/kg$ of CRF was intraperitoneally injected and stabilized for 30 minutes. Subsequently, intragastric 3 mL charcoal mix was administered, incubated for 10 minutes and the upper GI transit analyzed. Colonic transits were assessed after the same order and concentrations of trimebutine and CRF treatment by fecal pellet output assay. Results Different concentrations (1, 3, and $10{\mu}g/kg$) of rat/human CRF peptides was tested to establish the OS model in guinea pigs. CRF $10{\mu}g/kg$ was the most effective dose in the experimental OS model of guinea pigs. Trimebutine (3, 10, and 30 mg/kg) treatment significantly reversed the upper and lower GI transit of CRF induced OS model. Trimebutine significantly increased upper GI transit while it reduced fecal pellet output in the CRF induced OS model. Conclusions Trimebutine has been demonstrated to be effective on both upper and lower GI motor function in peripheral CRF induced OS model. Therefore, trimebutine might be an effective drug for the treatment of OS between FD and IBS patients.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.226-238
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• 2011

RAMS (Reliability, Availability, Maintainability, Safety) study has received far less rigorous analysis in the system performance and integration level, and RCM (Reliability Centered Maintenance) research has been studying to improve the maintenance efficiency in the operational steps based on collected data of real operational cases. This paper analyzes the basic concepts based on KS X ISO/IEC 15288 system life-cycle process in the whole system for the light rail transit construction, and the research suggests an approach to the management process of the applicable main tasks. The paper "Management Process Study to RAMS Application of Light Rail Transit System" introduces Airport Rail cases and guidelines by using RAMS which is the major role in the system engineering technical process of ISO/IEC 15288 (International Organization for Standardization/International Electrotechnical Commission 15288) to apply RAMS in domestic light rail transit efficiently, the aim of this study is to broaden of understanding RAMS.