• Journal of the Earthquake Engineering Society of Korea
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• v.18 no.4
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• pp.201-212
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• 2014

The plastic hinge region of RC pier ensures its nonlinear behavior during strong earthquake events. It is assumed that the piers secure sufficient strength and ductility in order to prevent the collapse of the bridge during strong earthquake. However, the presence of a lap-splice of longitudinal bars in the plastic hinge region may lead to the occurrence of early bond failure in the lap-splice zone and result in significant loss of the seismic performance. The current regulations for seismic performance evaluation limit the ultimate strain and displacement ductility considering the eventual presence of lap-splice, but do not consider the lap-splice length. In this study, seismic performance test and analysis are performed according to the cross-sectional size and the lap-splice length in the case of longitudinal bars with lap-splice located in the plastic hinge region of existing RC bridge columns with circular cross-section. The seismic behavioral characteristics of the piers are also analyzed. Based upon the results, this paper presents a more reasonable seismic performance evaluation method considering the lap-splice length and the cross-sectional size of the column.

• Journal of Acupuncture Research
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• v.17 no.3
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• pp.116-124
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• 2000

This clinical study was carried out 15 cases with lumbar spinal stenosis patients, who had been admitted and diagnosed by Computed Tomography from June, 1999 to May, 2000, in the department of acupuncture and moxibustion. Hanseo University Oriental Medical Nospital. The results obtained from this study were as follows; 1. We investigated 10 female and 5 male patients. The age distribution was from early 20's to 70's, among which 30's and 50's were most common. 2. The most common duration of symptom was less than a year(46.7%). 3. Regarding to the number of the involved levels, one was 12 cases(80%), two was 3 cases(20.0%). In the one level cases, L4~5 was the most common involved site. 4. Regarding to the clinical symptoms, low back pain was the most common, followed by lower extremity radiating pain, intermittent claudication, lower extremity paresthesia. 5. In orthopaedic examinations, positive sign in Milgram test was 80.0%, positive sign in straight leg raising test was 40.0%, and positive sign in Braggard test was 33.3%. Inneurologic examinations, sensory loss was seen in 60.0%, motor weakness and decreased deep tendon reflex were 26.7% in each. 6. According to clinical symptom scale proposed by Chae(1989), grade I1I was the most common (53.3%), followed by grade II, grade IV, grade I . 7. According to treatment outcome scale proposed by Chae(1989), Good was the most common (73.3%), followed by Excelleat, Fair and Poor.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.365-368
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• 2008

This research is related to 240MPa ultra-high strength concrete(UHSC) with extremely loss W/B ratio. For this development, High flow cement is mainly used which has a short reaction rate due to the high blaine and high early strength, which can make greater fluidity in case of very low W/C ratio. It made the best mixture using the mineral admixtures silica fume, slag powder and special admixture. For dispersibility and homogeneity of cement binder, cement of premix type is produced using omni-mixer. Moreover, it ensures the fluidity of ultra-high strength concrete(UHSC). For having a good fire performance, we made an experiment special coarse aggregate. As a result, we got 180MPa in case of water curing, 200MPa in case of steam curing and uniform UHSC of 240MPa in case of a special curing method.

• Journal of Periodontal and Implant Science
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• v.44 no.3
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• pp.109-117
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• 2014

Purpose: The aim of this study was to determine the effects of nutritional supplements on periodontal health and tooth mobility after surgery. Methods: Patients were randomly assigned to an intervention group who consumed nutritional supplement drinks for 8 weeks, while the placebo group did not receive any such supplements. The gingival index (GI) and tooth mobility were measured at baseline and at 1, 4, and 8 weeks. In addition, the oral health impact profile-14 and anthropometric measurements along with loss of appetite and dietary intake were assessed at baseline and 8 weeks. Results: At 1 week, GI values were reduced in the intervention group (P<0.05), and tooth mobility had increased, but to a lesser extent in the intervention group (P<0.05). At 8 weeks, the intakes of protein, vitamins A and B1, and niacin were increased in the intervention group. Conclusions: These results demonstrate that nutritional supplementation improves early periodontal healing after surgery.

• Journal of Gastric Cancer
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• v.11 no.4
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• pp.212-218
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• 2011

Purpose: Intracorporeal anastomosis during laparoscopic gastrectomy is becoming increasingly prevalent. However, selection of the anastomosis method after laparoscopic distal gastrectomy is equivocal because of a lack of technical feasibility and safety. We compared intracorporeal gastroduodenostomy with gastrojejunostomy using linear staplers to evaluate the technical feasibility and safety of intracorporeal anastomoses as well as its' minimally invasiveness. Materials and Methods: Retrospective analyses of a prospectively collected database for gastric cancer revealed 47 gastric cancer patients who underwent laparoscopic distal gastrectomy with either intracorporeal gastroduodenostomy or gastrojejunostomy from March 2011 to June 2011. Perioperative outcomes such as operation time, postoperative complication, and hospital stay were compared according to the type of anastomosis. Postoperative inflammatory response was also compared between the two groups using white blood cell count and high sensitivity C-reactive protein. Results: Among the 47 patients, 26 patients received gastroduodenostomy, whereas 21 patients received gastrojejunostomy without open conversion or additional mini-laparotomy incision. There was no difference in mean operation time, blood loss, and length of postoperative hospital stays. There was no statistically significant difference in postoperative complication or mortality between two groups. However, significantly more staplers were used for gastroduodenostomy than for gastrojejunostomy (n=6) than for gastroduodenostomy and (n=5). Conclusions: Intracorporeal anastomosis during laparoscopic gastrectomy using linear stapler, either gastroduodenostomy or gastrojejunostomy, shows comparable and acceptable early postoperative outcomes and are safe and feasible. Therefore, surgeons may choose either anastomosis method as long as oncological safety is guaranteed.

• Advances in pediatric surgery
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• v.13 no.2
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• pp.144-154
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• 2007

Liver tumors in children are rare, relatively complex, and encompass a broad spectrum of disease processes. This study reviews our experience of liver tumors during the last 10 years. Medical records of 36 cases of liver tumors in children, treated at Samsung Medical Centers, from October 1994 to December 2005, were reviewed in this study. We analyzed disease characters and survival rates as a whole and by specific disease. The median age was 3.6 years. Male and female ratio was 1:1. The most common symptom was the palpable mass in 15 cases. Others were abdominal distension in 9 cases, jaundice in 2, vomiting in 2, weight loss in 2, and pubic hair growth in 1. CT or US and liver biopsy were performed for diagnosis. There were 28 malignant tumors: malignant rhabdoid tumor (1 case), hepatocellular carcinoma (3 cases), hemangioendothelioma type II (3 cases), angiosarcoma (1 case), and hepatoblastoma (20 cases). Eight tumors were benign; hepatic adenoma (1 case), focal nodular hyperplasia (2 cases), hemangioendothelioma type I (2 cases), mesenchymal hamartoma (3 cases). In this study the clinical characteristics were not different from the other reports. Liver transplantation was performed in 3 cases-1 with hepatoblastoma and 2 with hepatocelleular carcinoma. Accurate and early diagnosis, and individualized multimodality therapeutic approaches might be important for better outcome.

• Korean Journal of Social Welfare
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• v.69 no.3
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• pp.9-33
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• 2017

This study estimated the socioeconomic costs of child poverty. Based on previous studies, the present study organized component categories for direct and indirect costs of child poverty, and estimated the cost of each category in 2015 through the collection of existing data and Delphi survey techniques among experts. The total socioeconomic costs of child poverty were compared to Korea's GDP. The results of this study were as follows. First, the socioeconomic costs of child poverty in Korea in 2015 ranged from 55 trillion KW(3.5% of GDP) to 99 trillion KW(6.5% of GDP). Second, the indirect socioeconomic costs of child poverty are much higher than the direct costs. Third, among the total cost categories, costs related to productivity loss and unemployment accounted for the largest portion of both the socioeconomic costs based upon absolute poverty and relative poverty. Crime costs are the second largest. Based on these results, we discussed the importance of early intervention for children in poverty; implementation of two-generation program that intervenes simultaneously with parents and children; and long-term, continuous and integrated intervention for high-risk groups such as poor children.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.6
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• pp.737-745
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• 2008

Recent developments of process and measurement technology bring much interest to the online monitoring of process operations such as milling, grinding, broaching, etc. The objective of online monitoring systems is to detect process changes as early as possible. This is helpful in protecting facilities against unexpected failures and then preventing unnecessary loss. This paper investigates, when the process monitoring data are obtained as a profile, the monitoring performances of a statistical $T^2$-statistic and a feedforward neural network by using a wavelet transform. Numerical experiments using cutting force data presented by Axinte show that the proposed wavelet based $T^2$-test has an acceptable power in detecting profile changes. However, its operating characteristic is very sensitive to autocorrelation. On the contrary, compared with $T^2$-test, the neural network has more stable performance in the presence of autocorrelation. This indicates that an adaptive feature to analyze noises should be incorporated into the wavelet based $T^2$-test.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.174-181
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• 1992

Early, mid, and late maturing soybean varieties were artificially infested with larvae of Delia platura at seeding, and then later development and productivity of soybeans were studied. In addition, in hope to utilize as possible tactics in the management of D. platura in soybeans, cultural factors such as contents of organic matter in soil, soil types, and the use of plastic mulching on the degree of damage to soybean plants by D. platura were examined. Primary leaf damage by the larva delayed the forthcoming vegetative growth but not the blooming which is initiated by the change in day length. Degree of delay in growth was more severe where leaf damage was induced by insect infestation than where artificially excised, apparently owing to simultaneous damage in stems and roots besides primary leaves. Productivity of soybeans also dropped significantly in plants with 25 % or more loss in the primary leaf area by the larva. Both transparent and black plastic mulchings shortened the period from seeding to emergence of soybean thus reducing the chance of possible attack by the larva. Soybean seedlings grown in clay loam or clay were attacked less by the larva than those in other types of soil. High organic matter content in the soil enhanced speed of emergence resulting in less larval damage to the seedling.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.293-306
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• 1991

During the last few years recommendations or regulations concerning permissible noise levels on shirts have been issued by the authorities in most countries. For these reasons the need for useful and accurate noise prediction computer programs has been emphasized. A noise prediction program can make it possible to find the most economical solution to achieve a certain noise requirement. This paper attempts to develop a noise prediction computer program using statistical energy analysis(SEA). In this paper, the SEA is used to predict the sound transmission loss for airborne noise and the vibration amplitude of the panel consisting of ship spaces such as floor, wall, and ceiling for structureborne noise. And in order to verify the prediction, a small passenger vessel, G/T120 tons, is selected. It has been shown that the prediction is capable of giving results in good practical agreement with measurements and therefore it is useful for predicting the nolle levels in ships and establishing the countermeasures at early design stage.