• Journal of the Korean Data and Information Science Society
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• 제14권4호
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• pp.889-901
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• 2003

In this paper, we consider the optimal replacement policies following the expiration of the combination warranty. The combination warranty can be divided into the renewing combination warranty and the non-renewing combination warranty. The criterion used to determine the optimal replacement period is the overall value function based on the expected cost and the expected downtime. Thus, we obtain the expected cost rate per unit time and the expected downtime per unit time for our model. And then the overall value function suggested by Jiagn and Ji(2002) is applied to obtain the optimal replacement period. The numerical examples are presented for illustrative purpose.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.48-53
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• 2001

A centrifugal fan design code was developed and included in $DasignFan^{TM}$. This program generates forward -curved and backward-curved bladed centrifugal fan data. With the inverse design concept used in the code, the period of designing a fm, which has given aerodynamic performance with minimal acoustic noise, is significantly shortened.. A centrifugal fan design code, developed in this study and included in $DasignFan^{TM}$, predicts the aerodynamic performance by using mean-line analysis and various loss models. In the period of design a lift force distribution between pressure side and suction side of blade is calculated. And then it is used to calculate steady loading noise from the impeller.

• 산업경영시스템학회지
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• 제10권15호
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• pp.23-32
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• 1987

This paper proposes a stepdown warranty policy: the warranty period consists of subintervals where the manufacturer's compensation is constant for warranty failures and decreases with the subinterval's number. Manufacturer's unit warranty cost is analyzed for both irrepairable and repairable products. we assume that only minimal repairs are performed for repairable items. Comparison with the free replacement polity indicates that the proposed policy has a longer warranty period if tile warranty reserves are the same and that manufacturer`s unit warranty cost is smaller if the warranty periods are tile same. Some numerical examples are also given.

• 대한치과보철학회지
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• 제28권1호
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• pp.217-224
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• 1990

Author examined clinical procedure, clinical application and clinical failure of castable glass ceramic (Dicor) crowns which were made at the Dept. of Prosthodontics, Seoul National University Hospital during 19 months from Jan. 1988 to July, 1989(Observation period:19 months). The author obtained the following results. 1. A total of 86 crowns were constructed ; Most of them has been set on maxillary central incisors(53 cases, 62%):maxillary lateral incisors(20 cases, 23%):maxillary canines(6 cases, 7%):others(7 cases, 8%) 2. Dicer could be used as a lamiate veneer for discolored tooth. 3. During the examination period(1-19 months), there was no fracture case. 4. Dicer could be applied on the maxillary anterior tooth with minimal occlusal force.

• 조명전기설비학회논문지
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• 제28권7호
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• pp.34-40
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• 2014

In this paper, we want to know the optimal replacement cycle(time) for this study was performed. The optimal preventive replacement age can be fond by finding the value of time that minimizes the cost function(model of Barlow and Jardine). In addition, The reliability of the relay according to the service environment were studied. The use of the exchange relay period is longer, and maintenance cost rate(per hour) may increase, and also the reliability may cause a decline. In addition, considering the preventive maintenance and purchase order, a representative relay(RAX-L440-A type) life was calculated.

• 복식문화연구
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• 제4권3호
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• pp.427-445
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• 1996

According as the fashion at the latter half part of the 20th century is diversified and made into high-class gradually, it is demanding the individuality of each one. Especially, since the beginning of 1980s, fashion came to represent the restoration mood in a modern style because of the popularization of post-modernism. And with this, it came to result in the reappearance of minimalism which was one of anti-culture in 1960s. In this study, this researcher grasped the appearance background, concept and structural concept of minimalism, and tried to study the influence that he minimalism had on fashion in the flow of fashion over the first half period of the 20th century. Minimalism is the fine art trend of American characteristic which quicked by the meeting of European culture and American culture, according as the new avant-grade art of Europe moved to America after World War II Minimalism which appeared, refusing the mechanisation, industrialization and mass production of America and the falsehood of consciousness and sensitivity under existing system remained obscure by the pop art which is the commercial fine art of same period, but it came to expand the domain of work possibility of modern fine art, and it became the basis of appearance of post-modernism. Minimalism has 4 kinds of structural features which are nonside nature, repetitiousness and environment nature with 3 dimensional feature which is issue nature. Minimalism is appearing in the exfcellent and future-oriented fashon of Andre Kureju t the time of 1960 well. Then science revolution and minimalism aroused the mini-revolution, and they made the compact radio in electric home appliances and the miniskirt in fashion appear. The features of minimal fashion as Retro '60' which appeared in the decedent mood with the 21st century just before on are as follows: First, the are the pursuit of concise plastic line. Second, it is the use of high tech material Third, the miniaturization in size amy be enumerated. Minimal fashion will appear s the positive confrontation from of mankind as the optimistic viewpoint about feature in the situation hat environment was destroyed and the resources were exhausted.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제23권5호
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• pp.423-429
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• 2020

Purpose: Alimentary tract duplication (ATD) is a rare congenital condition that may occur throughout the intestinal tract. Clinical symptoms are generally related to the involved site, size of duplication, or associated ectopic mucosa. This study aimed to identify clinical implications by anatomical locations and age group and then suggest a relevant management according to its distinct features. Methods: We retrospectively reviewed the clinical data of pediatric patients who received a surgical management due to ATD. Furthermore, data including patients' demographics, anatomical distribution of the duplication, clinical features according to anatomical variants, and outcomes were compared. Results: A total of 25 patients were included in this study. ATD developed most commonly in the midgut, especially at the ileocecal region. The most common clinical presentation was abdominal pain, a sign resulting from intestinal obstruction, gastrointestinal bleeding, and intussusception. The non-communicating cystic type was the most common pathological feature in all age groups. Clinically, prenatal detection was relatively low; however, it usually manifested before the infantile period. A laparoscopic procedure was performed in most cases (18/25, 72.0%), significantly in the midgut lesion (p=0.012). Conclusion: ATD occurs most commonly at the ileocecal region, and a symptomatic one may usually be detected before the early childhood period. Surgical management should be considered whether symptom or not regarding its symptomatic progression, and a minimal invasive procedure is the preferred method, especially for the midgut lesion.

• Journal of Periodontal and Implant Science
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• 제31권1호
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• pp.57-74
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• 2001

The purpose of this study was to evaluate the adjunctive combined effect of demineralized freeze-dried bone allograft(DFDB) in guided bone regeneration on supra-alveo-lar peri-implant defect. Supra-alveolar perio-implant defects, 3mm in height, each including 4 IMZ titanium plasma-sprayed implants were surgically created in two mongrel dogs. Subsequently, the defects were treated with 1 of the following 3 modalities: Control) no membrane or graft application, Group1) DFDB application, Group2) guided bone regeneration using an expanded polytetra-fluoroethylene membrane, Group3) guided bone regeneration using membrane and DFDB. After a healing period of 12-week, the animals were sacrificed, tissue blocks were harvested and prepared for histological analysis. Histologic examination were as follows; 1. New bon formation was minimal in control and Group 1, but considerable new bone formation was observed in Group 2 and Group 3. 2. There was no osteointegration at the implant-bone interface in the high-polished area of group2 and Group 3. 3. In fluorescent microscopic examination, remodeling of new bone was most active during week 4 and week 8. There was no significant difference in remodeling rate between group 2 and group 3. 4. DFDB particles were observed, invested in a connective tissue matrix. Osteoblast activity in the area was minimal. The results suggest that guided bone regeneration shows promising results in supra-alveolar peri-implant defects during the 12 week healing period although it has a limited potential in promoting alveolar bone regeneration in the high-polished area. There seems to be no significant adjunctive effect when DFDB is combined with GBR.

• 대한족부족관절학회지
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• 제9권2호
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• pp.173-178
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• 2005

Propose: There have been many debates about the ideal surgical technique for acute Achilles tendon rupture. The purpose of this study is to review and analyze the clinical outcome of the acute Achilles tendon ruptures that had been repaired by indirect suture technique with minimal incision that utilized an instrument called Achillon (Newdeal, France). Materials and Methods: This study is based on the 14 cases (14 patients) of acute Achilles tendon total ruptures that have been repaired by minimal incision technique utilizing Achillon instrument from June 2003 to December 2004. Two cases were reruptured before 8 weeks and repaired again using Krackow suture which left 12 feet for postoperative functional evaluation with at least 6 months of follow-up. Ten cases were men and average age at time of injury was 34.4 (26-49) years. The time from injury to surgery was an average of 4.5 (1-9) days and the postoperative evaluations were done by an Arner-Lindholm scale and AOFAS score. The ability to return to original work and sports activities as well as patient satisfaction were also evaluated. Results: The follow-up period was averaged for 13.2 (6-24) months. Seventy-one percent of cases were ruptured during sports activities. The ruptured level was the average of 5.1 cm (3.2-8 cm) above calcaneal attachment and the skin incision was averaged for 2.7 cm (2.5-3.0 cm) long. At final follow-up, standing on tip-toe was possible in all cases while the heel-floor height on ruptured side was shorter by 0.7 cm (0-2 cm). By Arner-Lindholm evaluation scale, 9 cases were excellent, and 3 cases were good. Overall AOFAS score was an average of 96.1 (94-100), and all patients were satisfied with the result. Patients returned to work at an average of 1.3 months after the surgery and pre-injury sports activities were all possible from at 6 months after operation. Conclusion: Since we have treated acute Achilles tendon ruptures with minimal incision technique utilizing the Achillon and gained encouraging functional results with all patients returning to previous work with high patient satisfaction, this technique could be recommended as one of the ideal surgical options for the Achilles tendon ruptures.

• Archives of Plastic Surgery
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• 제44권3호
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• pp.210-216
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• 2017

Background In treating minor-form or microform cleft lip, obtaining an optimal result is a challenge because of the visible scarring caused by traditional surgery. We present a refined method using muscle overlapping with a minimal skin incision in patients younger than 3 years, a group characterized by thin muscle. Methods The surgical technique involves restoration of the notched vermillion using Z-plasty, formation of the philtral column using overlapping of an orbicularis oris muscle flap through an intraoral incision, and correction of the cleft lip nasal deformity using a reverse-U incision and V-Y plasty. A single radiologist evaluated ultrasonographic images of the upper lip. Results Sixty patients were treated between September 2008 and June 2014. The age at the time of operation ranged from 6 to 36 months (mean, 26 months). The follow-up period ranged from 8 to 38 months (mean, 20 months) in minor-form cases and from 14 to 64 months (mean, 37 months) in microform cases. A notched cupid's bow was corrected in 10 minor-form cases and 50 microform cases. Ultrasonographic images were obtained from 3 patients with minor-form cleft lip and 9 patients with microform cleft lip 12 months after surgery. The average muscle thickness was 4.5 mm on the affected side and 4.1 mm on the unaffected side. Conclusions The advantages of the proposed procedure include the creation of an anatomically natural philtrum with minimal scarring. This method also preserves the continuity and function of the muscle and provides sufficient augmentation of the philtral column and nostril sill.