• Journal of the Korea Concrete Institute
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• v.14 no.5
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• pp.698-707
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• 2002

A review is presented of experimental studies on the strength performance of concrete exposed at short-term and rapid heating as in a fire and after cooling. Emphasis is placed on concretes with high original compressive strengths, that is, high-strength concrete(HSC). The compressive strength-temperature relationships from the reviewed test programs are distinguished by the test methods used in obtaining the data(unstressed, unstressed residual strength, and stressed tests) and by the aggregate types(normal or lightweight), The compressive strength properties of HSC vary differently with temperature than those of NSC. HSC have higher rates of strength loss than lower strength concrete in the temperature range of between 20$^{\circ}C$ to about 400$^{\circ}C$. These difference become less significant at temperatures above 400$^{\circ}C$ compressive strengths of HSC at 800$^{\circ}C$ decrease to about 30 ％ of the original room temperature strength. A comparison of lest results with current code provisions on the effects of elevated temperatures on concrete compressive strength and elastic modulus shows that the CEN Eurocodes and the CEB provisions are unconservative.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.4 s.304
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• pp.95-102
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• 2005

In this paper, we propose a user friendly object-based image retrieval system using the interaction between cortex and hippocampus. Most existing ways of queries in content-based image retrieval rely on query by example or query by sketch. But these methods of queries are not adequate to needs of people's various queries because they are not easy for people to use and restrict. We propose a method of automatic color object extraction using CSB tree map(Color and Spatial based Binary をn map). Extracted objects were transformed to bit stream representing information such as color, size and location by region labelling algorithm and they are learned by the hippocampal neural network using the interplay between cortex and hippocampus. The cells of exciting at peculiar features in brain generate the special sign when people recognize some patterns. The existing neural networks treat each attribute of features evenly. Proposed hippocampal neural network makes an adaptive fast content-based image retrieval system using excitatory learning method that forwards important features to long-term memories and inhibitory teaming method that forwards unimportant features to short-term memories controlled by impression.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.434-440
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• 2009

Background: Surgical closure of a patent ductus arteriosus (PDA) can be considered when conservative medical treatment is ineffective or contraindicated. Low weight and earlier gestational age neonates who are treated with conservative medical therapy generally showed a higher failure rate. The morbidity of surgical PDA closure in such extremely low birth weight (ELBW) neonates is also high. Here we present the early results of a new technique for approaching the PDA through a dorsal minithoracotomy. Material and Method: From March 2006 to November 2008, 24 premature neonates underwent surgical PDA closure. The procedures were performed in the newborn intensive care unit via a 2 cm long dorsal minithoracotomy with the baby in the prone position with the left hemithorax elevated 30$^{\circ}$. Bimanual cotton swab blunt dissection completed the extrapleural accesstothe PDA and then two clips were applied. Tube thoracostomy was avoided if there was no meaningful pleural laceration. Result: The infants mean gestational age was 26.5$\pm$2.1 weeks (range: 23 to 30 weeks) and the average age at operation was 11$\pm$11 days. The mean body weight at operation was 933$\pm$271 grams (range: 570 to 1,700 grams). Eight patients expired, but there was no procedure-related death. Postoperative echocardiography revealed two cases of residual shunt but none of these shunts were detected on the follow up echocardiogram that was performed on the post operative 5 and 59 days. Conclusion: We concluded that the technique described here is an effective procedure in view of the satisfactory operative exposure and the low rate of complications.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.621-627
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• 1999

Background: Sixty five cases with congenitally corrected transposition of the great arteries (CCTGA) indicated for biventricular repair were operated on between 1984 and september 1998. Comparison between the results of the conventional(classic) connection(LV-PA) and the anatomic repair was done. Material and Method: Retrospective review was carried out based on the medical records of the patients. Operative procedures, complications and the long-term results accoding to the combining anomalies were analysed. Result: Mean age was 5.5$\pm$4.8 years(range, 2 months to 18years). Thirty nine were male and 26 were female. Situs solitus {S,L,L} was in 53 and situs inversus{I,D,D} in 12. There was no left ventricular outflow tract obstruction(LVOTO) in 13(20%) cases. The LVOTO was resulted from pulmonary stenosis(PS) in 26(40%)patients and from pulmonary atresia(PA) in 26(40%) patients. Twenty-five(38.5%) patients had tricuspid valve regurgitation(TR) greater than the mild degree that was present preoperatively. Twenty two patients previously underwent 24 systemic- pulmonary shunts previously. In the 13 patients without LVOTO, 7 simple closure of VSD or ASD, 3 tricuspid valve replacements(TVR), and 3 anatomic corrections(3 double switch operations: 1 Senning+ Rastelli, 1 Senning+REV-type, and 1 Senning+Arterial switch opera tion) were performed. As to the 26 patients with CCTGA+VSD or ASD+LVOTO(PS), 24 classic repairs and 2 double switch operations(1 Senning+Rastelli, 1 Mustard+REV-type) were done. In the 26 cases with CCTGA+VSD+LVOTO(PA), 19 classic repairs(18 Rastelli, 1 REV-type), and 7 double switch operations(7 Senning+Rastelli) were done. The degree of tricuspid regurgitation increased during the follow-up periods from 1.3$\pm$1.4 to 2.2$\pm$1.0 in the classic repair group(p<0.05), but not in the double switch group. Two patients had complete AV block preoperatively, and additional 7(10.8%) had newly developed complete AV block after the operation. Other complications were recurrent LVOTO(10), thromboembolism(4), persistent chest tube drainage over 2 weeks(4), chylothorax(3), bleeding(3), acute renal failure(2), and mediastinitis(2). Mean follow-up was 54$\pm$49 months(0-177 months). Thirteen patients died after the operation(operative mortality rate: 20.0%(13/65)), and there were 3 additional deaths during the follow up period(overall mortality: 24.6%(16/65)). The operative mortality in patients underwent anatomic repair was 33.3%(4/12). The actuarial survival rates at 1, 5, and 10 years were 75.0$\pm$5.6%, 75.0$\pm$5.6%, and 69.2$\pm$7.6%. Common causes of death were low cardiac output syndrome(8) and heart failure from TR(5). Conclusion: Although our study could not demonstrate the superiority of each classic or anatomic repair, we found that the anatomic repair has a merit of preventing the deterioration of tricuspid valve regurgitations. Meticulous selection of the patients and longer follow-up terms are mandatory to establish the selective advantages of both strategies.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.146-153
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• 2004

As the experience of coronary artery bypass grafting (CABG) has been accumulated, the number of reoperation after CABG is increasing. We analyzed our clinical experience of redo-CABG. Material and Method: Fourteen patients who underwent redo-CABG between Jan. 1994 and Dec. 2002 were included in this study. The mean period from the first operation to reoperation was 66$\pm$56 (3∼157) months, and the average ages were 62.8$\pm$8.7 (51∼78) years. The survivors were followed up 39$\pm$29 (4∼101) months postoperatively. Indications of reoperation were stenosis or occlusion of previous grafts in 11 patients, progression of native coronary artery disease in one patient, and both etiologies in two patients. Result: There were two in-hospital mortalities (14.3%) resulting from low cardiac output syndrome, Postoperative morbidities were perioperative myocardiac infarction in 2 patients (14.3%), mediastinitis in one patient (7.2%), duodenal perforation in one patient, ischemic necrosis of the lower extremity in one patient, gastric perforation after mesenteric infarct in one patient, delayed brain infarct in one patient, and intraoperative splenic rupture in one patient. There was one late mortality at six months postoperatively during the follow up. There was no angina recurrence during the follow up. Conclusion: Although redo CABG demonstrated relatively high operative mortalities and morbidities, postoperative status and clinical outcome of the survivors were favorable.

• Journal of Practical Engineering Education
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• v.12 no.1
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• pp.109-116
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• 2020

The effects of mentoring education bring positive effects such as mentees' capacity building, knowledge improvement and positive attitude. The major difficulties that nursing college students experience in clinical practice are low adaptability, lack of confidence, etc. Therefore, this study developed mentoring education program to improve the problem-solving ability, learning attitude, and confidence in nursing skill before clinical practice for nursing college students and evaluated their effectiveness. In order to develop the program, a group of experts consisting of professors and clinical nurses selected 11 topics after discussing nursing skills and knowledge, which were most required in clinical practice. The program involved 14 mentors who operated practice, counseling, video clips, and contextual discussions for two days to a group of 9 to 10 people. Nursing college students who received the mentoring education program showed a significant increase in learning attitude and confidence in performance of nursing skills, but there was no statistically significant difference in problem-solving ability. This study is meaningful in that it has improved the educational effect by using mentoring methods, away from formal in-school practice education. In the future, it will be necessary to evaluate whether the mentoring education program affect the problem-solving ability of nursing students by applying it before, during, and after clinical practice rather than in a short period.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.727-738
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• 2002

This study was conducted to investigate the effect of essential amino acid(EAA) deficient diets on short-term feeding response and the Fos expression in brain area when methionine deficiency diet fed, and thereby to know the mechanism of feed intake regulation. In all trials, experimental diets were formulated with pure amino acid mixture to level of 15% nitrogen. Rats were adapted to a 6-hr single-meal feeding per day(17:00${\sim}$21:00). Feed intake and body weight were monitored every hour after 7-day of feeding of individual EAA deficient diets in Exp. Ⅰ. In Exp. Ⅱ, Fos immuno- histochemistry was determined in various regions of brain to identify the regions that is related to suppressed feed intake following feeding methionine-deficient diet. Fos expression was examined to know the initial sensitive region in the brains of rats at 3h after feeding of the control and methionine deficient diet(-Met). Initial response to EAA deficiency diets was severely depressed in methionine deficiency diet, but the depression was low in threonine deficiency diet. However, the feed intake at 3rd day in rats was depressed in the order of His(71%), Leu(68%), Ile(66%), Thr(63%), Trp(61%), Val(55%), Phe(52%), Met(51%), Lys(44%) and Arg(24%). Fos immunoreaction in neural regions(PPC, amygdala and EPC) of pyrifrom cortex was increased in the -Met group more than in the control diet group, but those in LH, VMH and PVM were similar. Thus, based on these data, the PPC was identified as the initial response area in the -EAA diet.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.2
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• pp.179-190
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• 2012

The installation of an implant in the distal extension area to assist a partial dentrue (IARPD) was used carefully in clinical situations. The purpose of this review on the IARPD is describing the concept, clinical results and guidelines of IARPD. For the review, a literature search was performed using the PubMed. The data from the literature suggest that the placement of the implants could improve function and patient satisfaction. In addition, IARPD reduced the residual ridge resorption. Longer and wider implant should be placed. Less than $15^{\circ}$ angulation may be not harmful. To prevent the loosening of the abutment, modified abutment or resilient attachment should be used. However, the connection method between the clasp retention and IARPD should be considered for long time success. Moreover, longitudinal clinical studies are required for evaluation of IARPD.

• Journal of Chest Surgery
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• v.39 no.7 s.264
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• pp.544-548
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• 2006

Background: The purpose of this study is to evaluate the validity of a combined high saphenous vein division and sclerotherapy without sacrificing saphenous vein for varicose vein. Material and Method: Between August 2004 and October 2005, 70 limbs in 50 patients were treated by a combined high saphenous vein division and sclero-therapy. The operative indication is valvular incompetence of femoral-saphenous or popliteal-saphenous junction. Patients received local anesthesia and were treated by a combined high saphenous vein division, ligation of incompetent perforating vein and $1{\sim}3%$ sclerosant. Patients received 1 day hospitalization and applied in com-pression stocking for 6 weeks. Patients followed after 1 week, 1 and 3 months. Result: Mean age of patients was $50{\pm}11$. The female was more common. 8 patients was no symptom, another 42 patients complained of pain, heaviness and fatigue of limbs. The symptoms of varicose vein disappeared 1 month after the procedure in all symptomatic patients. 8 patients needed a adjuvant sclerotherapy for residual varicose vein on 1 week after the procedure. There were only minor complications such as hematoma (1), wound infection (1), thrombophlebitis (20), skin blister (10), hyper-pigmentation (1), and skin ulcer (1). Conclusion: We concluded that a combined high saphenous vein division and sclerotherapy without sacrificing saphenous vein for varicose vein is simple, less invasive, economical, and effective treatment for primary varicose vein, and it has a special advantage that saphenous vein can be used as a bypass conduit later. The method was selective in old aged patients.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.371-384
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• 1982

Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.