• Journal of Environmental Science International
• /
• v.17 no.11
• /
• pp.1281-1293
• /
• 2008

This study aims at the estimation of dam failure time and dam failure scenario analysis of and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-HMS, DAMBRK-FLDWAV simulation model. As the result of the rainfall-runoff simulation, the lancet flood amount of the Yeoncheon Dam site was $10,324\;m^3/sec$ and the total outflow was $1,263.90\;million\;m^3$. For the dam failure time estimation, 13 scenarios were assumed including dam failure duration time and starting time, which reviewed to the runoff results. The simulation time was established with 30 minutes intervals between one o'clock to 4 o'clock in the morning on August 1, 1999 for the setup standard for each case of the dam failure time estimation, considering the arrival time of the flood, when the actually measured water level was sharply raising at Jeongok station area of the Yeoncheon Dam downstream, As results, dam failure arrival time could be estimated at 02:45 a.m., August 1st 1999 and duration time could be also 30 minutes. Those results and procedure could suggest how and when dam failure occurs and analyzes.

• Journal of Environmental Science International
• /
• v.17 no.11
• /
• pp.1295-1305
• /
• 2008

This study aims at the analyze of unsteady downstream flow due to dam failure along dam failure scenario and applied to Yeoncheon Dam which was collapsed August 1st 1999, using HEC-RAS simulation model. The boundary conditions of this unsteady flow simulation are that dam failure arrival time could be at 02:45 a.m. August 1st 1999 and failure duration time could be also 30 minutes. Downstream 19.5 km from dam site was simulated for unsteady flow analysis in terms of dam failure and non-failure cases. For the parameter calibration, observed data of Jeonkok station were used and roughness coefficient was applied to simulation model. The result of the peak discharge difference was 2,696 to $1,745\;m^3/sec$ along the downstream between dam failure and non-failure and also peak elevation of water level showed meanly 0.6m difference. Those results of these studies show that dam failure scenarios for the unknown failure time and duration were rational because most results were coincident with observed records. And also those results and procedure could suggest how and when dam failure occurs and downstream unsteady flow analyzes.

• Journal of Periodontal and Implant Science
• /
• v.34 no.4
• /
• pp.723-731
• /
• 2004

Helicobacter pylori(H. pylori) has been associated with the cause of chronic gastritis, peptic ulcers and gastric cancer. Although it may be transmitted through the oral cavity, it is unknown whether the oral cavity acts as a reservoir of H. pylori. The purpose of this study was to investigate the mode of detection of H. pylori in oral cavity of adult periodontitis patients with plaque and periodontal pocket which atmosphere is grown well H. pylori. We analysed detection rate of H. pylori in saliva and subgingival plaques of 17 adult periodontitis patients without symptoms of gastroduodenal disease by nested PCR. Samples tested comprised saliva and subgingival plaques from central incisor, 1st premolar and 1st molar. H. pylori DNA was not identified in saliva from all patients. The detection rate in subgingival plaque from incisors, premolars and molars was 5.9%, 5.9% and 17.7%, respectively. In conclusion, the dental plaque and periodontal pocket (especially, of molars) in adult periodontitis can be favorable reservoir of H. pylori and may be the source of infection and transmission of H. pylori.

• Journal of Korean Association for Spatial Structures
• /
• v.17 no.4
• /
• pp.115-122
• /
• 2017

In this study, performance based seismic design was performed on the shear wall structural system and the beam-column system as a variable general rebar and seismic rebar, and comparing the capacity of the two models of each system. From nonlinear analyses, the capacity of the shear wall structural system applying seismic rebar has shown a stable behavior after the maximum strength, but there is little difference. Furthermore, both models showed similar capacity between story drift and story shear force and capacity of members. These results are attributed to the fact that the seismic rebar, which is highly ductile under the seismic load applied to the target structure, does not render sufficient capacity.

• Pediatric Gastroenterology, Hepatology & Nutrition
• /
• v.17 no.3
• /
• pp.186-190
• /
• 2014

Lymphocytic gastritis (LG) is a rare subtype of chronic gastritis. It is defined as dense proliferation of intraepithelial lymphocytes (IELs) more than 25 lymphocytes per 100 epithelial cells. The known major causes of LG are celiac disease and Helicobacter pylori infection. H. pylori associated LG (HpLG) has more enhanced cytotoxic and apoptotic tendencies than chronic H. pylori gastritis. A 12-year-old girl with postprandial epigastric pain was diagnosed HpLG on endoscopic biopsy. After the 1st eradication therapy, H. pylori bacilli were still found, and urea breathing test was positive. Although the endoscopic finding was partially improved, clinical symptoms and histologic finding were persisted. We could achieve the improvement of clinical symptoms and disappearance of IELs after the 2nd eradication. The discordant of histopathologic and endoscopic improvement occurred after the 1st eradication therapy of HpLG. Therefore the clinical and histopathologic evaluation should be considered as well as endoscopic findings.

• The Journal of Pediatrics of Korean Medicine
• /
• v.13 no.1
• /
• pp.239-252
• /
• 1999

Selection of therapeutic modality for 114 patients with night crying was clinical1y recorded from October 1st, 1996. to Spring 1st, 1998. 1. The number of male cases was 67 (58.77%) and female cases was 47 (41.23%) and so male cases were 1.43 more than female. The patients between 7 and 12 months were 28.07% (most frequent), between 3 and 6 months were 23.68%, 1 and 3 years were 21.05%. 2. Duration of disease was for 7 days to 6 months and over, and the group within 7 days highest portion as 57.25%, between 1 and 4 weeks was 21.05%, 6 months and over was 12.28%. 3. Distribution of contributing factors was in the order of 50% of nonspecific factors, 17.54% of fall-down. 4. Distribution of complicated signs, in order of 39.47% of poor sleeping, 33.33% of easy surprizing, 16.67% of green stool, 10.53% of loose form stool. 5. Distribution of theraphic method was as follows: ⅰ) group treated with acupunture and woohwangporyonghwan(WPH) (35.09%), ⅱ) acupunture, WPH, and Gamiyangshintang(33.33%), ⅲ) acupuncture, WPH, and Hyangshapungyuisan (15.79%), 6. From the above results a remakable effct was 92.1%, of which 74.56% was excellent and 17.54% was good.

• Journal of Korea Foundry Society
• /
• v.37 no.4
• /
• pp.101-107
• /
• 2017

This study investigated the effect of Pd on the microstructure, tensile and creep properties of Mg-4Al-2Sn (AT42) alloy at a high temperature for transportation-related industrial applications. AT42-xPd (x = 0, 1 and 2 wt. %) alloys were prepared using a permanent mould casting method. The microstructures of the as-cast alloys were characterized by the presence of the intermetallic phases $Mg_{17}Al_{12}$, $Mg_2Sn$ and $Al_4Pd$. The addition of Pd was found to improve the tensile properties of AT42 at room and at elevated temperatures, and to increase the creep resistance at elevated temperatures. A small amount of Pd could markedly improve the tensile properties of AT42 by means of grain-refinement and the dispersion of secondary phase strengthening. Moreover, the thermally stable phase $Al_4Pd$ effectively improves the creep resistance of AT42 due to the strengthened grain boundaries and the suppressed formation of $Mg_{17}Al_{12}$.

• Journal of Korean Association for Spatial Structures
• /
• v.17 no.1
• /
• pp.31-40
• /
• 2017

The objective of this study is to analysis the mechanical characteristics and nonlinear behaviors on the geometric nonlinear behavior of a cable spoke wheel roof system for long span lightweight roof structures. The weight of a cable spoke wheel roof dramatically can reduce and the cable roof system can easily make the required rigidity and shape by the sag ratio and pretension forces. Determining the pretension and initial sag of cable roof system is essential in a design process and the shape of roof is changed by pretension. The nonlinear behavior of flexible cable system has greatly an affect on the sag and pretension. This paper will be carried out analyzing and comparing the tensile forces and deflection of a cable spoke wheel system for the large span retractable roof, and analyzed to deflections and tensile forces by the post height of center hub. The double arrangement of a spoke wheel system with reverse curvature works more effectively as a load bearing system, the pretension can easily increase the structural stiffness. The cable truss system can carry vertical load in up and downward direction, and act effectively as load bearing elements.

• Journal of Fashion Business
• /
• v.17 no.4
• /
• pp.177-190
• /
• 2013

The purpose of this study is 1) to investigate the types of upscale fashion department stores' Facebook page contents, 2) to compare the types of Facebook page contents with the department stores, and 3) to explore the dimensions of the Facebook page components and their relations. For the study, three preeminent department stores in social media marketing were chosen: Bergdorf Goodman, Barneys New York, and Saks Fifth Avenue. Three hundred sixty five contents of these department stores' pages were investigated, which were uploaded from February 1st to March 31st of 2013. Content analysis, correspondence analysis, and categorical principal component analysis were used for the research. The result showed that there are four important types of contents in pages: product-related contents, fashion-related contents, department stores-related contents, and the contents of communicating with users. And these components of contents were related with department stores distinctively. The two dimensions of the page components were revealed: the basic components (contents, 'like', 'share', and 'comments') and the additional components (links and photos). Among contents, the introduction of products was appealed but news and events were not liked by users; the contents without a photo were not linked to additional information either.

• Journal of Korean Clinical Nursing Research
• /
• v.17 no.1
• /
• pp.35-45
• /
• 2011

Purpose: The purpose of this study was to identify the effect of exercise therapy on low back pain, self-urination disorder, bleeding, and hematoma in Percutaneous Coronary Intervention (PCI) patients. Methods: A total of 64 PCI patients were recruited from C hospital located in C city, from June until August of 2010. The patients were divided into two groups as the exercise and control group. Thirty-two participants in the exercise group took bedrest for two hours after PCI, and then received excise therapy. The other 32 participants in the control group took the usual 8-hour bedrest with intermittent back care by the unit nurses. Results: In the relieving effect of low back pain, exercise group reported pain reduced faster than the control group. On the other hand, there were no significant differences between the two groups in alleviant of self-urination disorder, bleeding, and hematoma. Conclusion: Exercise therapy for reducing patients' low back pain showed to be an effective nursing intervention. Since there was no bleeding or hematoma after PCI in the exercise group, this study provided the ground suggesting that it might be possible to reduce the bedrest time after PCI without increased risk of bleeding or hematoma.