• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.139-146
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• 1995

This study is concerned with cost analysis in periodic maintenance policy. Generally periodic maintenance policy in which item is repaired periodic interval times. And in the article minimal repair is considered. Minimal repair means that if a unit fails, unit is instantaneously restored to same hazard rate curve as before failure. In the paper periodic maintenance policy with minimal repair is as follows; Operating unit is periodically replaced in periodic maintenance time, if a failure occurs between minimal repair and periodic maintenance time, unit is replaced by a spate until the periodic time comes. Also unit undergoes minimal repair at failures in minimal-repair-for-failure interval. Then total expected cost per unit time is calculated according to maintenance period and scale parameter of failure distribution. Total cost factors ate included operating, fixed, minimal repair, periodic maintenance and replacement cost Numerical example is shown in which failure time of system has erlang distribution.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.4
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• pp.35-41
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• 2007

The most agricultural concrete structures for the irrigation and drainage are exposed to the underwater condition at the irrigation period and they take the influence on very severe cold in the winter. Therefore, it is impossible to use repair materials used to the general concrete structures. The research need the development of the repair material for a performance enhance of the agricultural underwater concrete structures. This research evaluated the mechanical and durability performance of the latex modified repair mortar for underwater concrete structures which peformed the repair in the underwater according to the characteristic of the agricultural concrete structure. The latex modified repair mortar is a material that minimize the effect of the ecosystem, environment and the segregation. In this research, the construction condition of the latex modified repair mortar for agricultural concrete structures was considered and the test specimens made in the underwater condition. Test results was then compared with target performance and commercial repair mortar. Experimental test results indicated that the mechanical and durability performance of latex modified repair mortar for agricultural underwater concrete structure satisfied all target performance. Also, the latex modified repair mortar resulted in better repair performance than the commercial repair mortar.

• Clinics in Shoulder and Elbow
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• v.9 no.2
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• pp.176-180
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• 2006

Purpose: Although surgical arthroscopic repair of rotator cuff has become much more common as surgeons have developed proficient techniques, it is still technically difficult. The purpose of this study was to evaluate the clinical results and the usefulness of mini-open repair in large and massive size tears. Materials & Methods: From January 2000 to December 2004, sixteen patients were treated with mini-open repair. There were 10 male and 6 female patients with the average age of 62.5 years. The size of tear was massive in 4 cases and large in 12 cases. All tears were repaired with metal anchor sutures. The mean duration of follow-up period was 23 months. Postoperative results were evaluated based on American Shoulder and Elbow Society scoring system. Results: Five patients showed excellent results, five good, and two fair in large tears while one patient showed excellent result, one good, and two fair in massive tears. Poor outcome was not seen during the follow-up period. There was no significant relationship between the patient's age and the size of tear, and postoperative results. However, the relationship between the duration of symptomatic period in preoperation and postoperative results showed significant correlation. Conclusion: Mini-open repair combined with the preservation of deltoid and early rehabilitation is clinically useful in large and massive size rotator cuff tear patients treatment.

• Clinics in Shoulder and Elbow
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• v.9 no.1
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• pp.105-110
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• 2006

Purpose: This study reports the clinical results of the arthroscopic Bankart repair in traumatic anterior instability of the shoulder with bio-knotless anchor. Materials and Methods: 21 cases of 21 patients (20 male and 1 female) were included in this study. The average age was 24.8 years old and the period from the first injury to operation was average 37.2 months. All cases had Bankart lesion and 12 cases had Hill-Sachs' lesion. The SLAP lesion was associated in 6 cases. Preoperative Rowe score was average 29.1. Arthroscopic Bankart repair with bio-knotless anchor were performed in all cases; 3 anchors at 3, 4, 5 O'clock position of the glenoid were used in 11 cases and 2 anchors at 4, 5 O'clock position were used in 10 cases. All the associated SLAP lesions were repaired arthroscopically with bio-knotless anchor. Thermal capsular shrinkage at the anterior and inferior shoulder capsule after the Bankart repair was performed in 3 cases. The average follow up period was 20.2 months. Results: The Rowe score improved to 92.8, excellent in 17 cases and good in 4 cases, at last follow up period and 20 cases had full range of motion of the shoulder. 1 case had mild limited range of motion of the shoulder (150 degrees in flexion, 60 degrees in external rotation and T12 level in internal rotation) without any problem in normal activity. The arthroscopic revision surgery of the shoulder was performed in 1 case because of multiple traumatic injuries of the shoulder with pain postoperatively. Conclusion: Arthroscopic Bankart repair with bio-knotless anchor in traumatic anterior shoulder instability is one of the good methods because of the good clinical results.

• KIEAE Journal
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• v.16 no.3
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• pp.137-143
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• 2016

Purpose: Apartment housing should conduct a cyclic repair to keep and maintain the building performance since they are constructed. Therefore, the repair plan would be provided for long term period which explains the repair time, items and repair cost. Residents of apartment housing are responsible to pay for the repair activities. For repair cost, residents would reserve the money for repair little by little continuously until the required repair time because the repair cost takes a big burden for residents and lots of money a time. But, there is no systematic approach to provide the long term repair cost because it is no proper forecast of the repair cost to the upcoming repair time. In this study, it aimed at providing the monthly accumulation of the long term repair cost with the survey data in Seoul. Method: For these, the surveyed data are classified into 6 categories and number of data are 1,918. In addition, it developed the repair cost model for the 24 repair works and the cumulation function which is reflected with the each cost model. Result: This study are shown as follows : First, among the various estimation for the repair cost, the power function has a goodness of fit in statistics. Second, the monthly accumulation would be 12,840 won/household in size of $100,000m^2$ management area and $81.7won/m^2$ in size of the 1,000 household number during 40 years.

• Journal of Chest Surgery
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• v.32 no.10
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• pp.966-969
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• 1999

Congenital defects of the sternum are rare development anomalies. They result form the failure of the lateral sternal bars to fuse. This malformation may be associated with other ventral midline fusion defects and ectopia cordis. A complete sternal cleft is the rarest form and less than 10 cases have been reported in the medical literature. Here were report a 3-day-old boy with complete sternal cleft without other malformations, who underwent primary surgical repair. Surgical correction of complete sternal cleft should be performed in neonatal period whether the infant if symptomatic or not because it is usually simple, able to achieve good result and primary repair is usually feasible at this period.

• Journal of Korea Port Economic Association
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• v.38 no.3
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• pp.69-86
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• 2022

This study analyses the necessity of the large-size shipyard and explores competitiveness factors of it. Furthermore, the competitiveness is evaluated and the economic feasibility of building and operation of shipyard is examined. As a result of AHP analysis of the determining factors of the competitiveness of the repairing shipyard, the importance of the factors was found in the order of arrival and departure safety, repair technology, dock and wharf facilities, repair cost, repair period (on time delivery), and repair parts supply. Moving distance, repair service quality, repair parts supply, arrival and departure safety, repair technology, dock and quay wall facilities, and repair period (on time delivery) were identified as key factors in the AHP analysis for competitiveness of the Busan Port repair shipyard to be built in the future. As a result of the analysing economic feasibility, the net present value of the Busan Port repair shipyard construction and operation investment project was KRW 435.6 billion, and the internal rate of return was 9.8%, higher than the social discount rate (4.5%), and the cost-benefit ratio (B/C) was high at 1.167. As a result of the study, the necessity and economic feasibility of the Busan Port repair shipyard are sufficiently ensured, and the competitiveness assessment was highly positive.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.16 no.27
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• pp.21-25
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• 1993

This article is concerned with cost analysis in stepdown warranty policy. The repair of item is divided into two policies. First, perfect repair can be considered that the failurerate is the same as new item. Second, minimal repair is shown that the failurerate is the same as just before the item failure In this paper, the minimal repair model is introduced. And it is assumed that manufacturers repair the item failure within the warranty periodn. But warranty period is not renewed at all. At this point the warranty cost is analyzed in manufacturer's and customer's point of view.

• Journal of Korean Society for Quality Management
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• v.28 no.3
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• pp.53-58
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• 2000

In many cases, it is more practical and economical to repair a system than to replace the whole system or to perform a complete overhaul when it fails. The age replacement policy with minimal repair at failure is considered. The system is replaced every time its age reaches at $T_0$. For each intervening failure only minimal repair is done. The minimal repair times in a renewal period are increasing in the sense that the minimal repair times constitute a strictly increasing geometric process. The long-run expected cost rate Is obtained and the properties of the existence and the uniqueness of the optimal policy minimizing the long-run expected cost rate are derived.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.473-481
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• 2017

With the barracks modernization project, the Ministry of National Defense has been operating 60 projects of the 75 that have been announced. It was difficult to investigate and analyze the data in the past because data could not be obtained while it was much easier to do that since data can be obtained from private companies. With the aim of increasing the usability of the facilities, the objective of this study is to present a reasonable alternative for repair and maintenance costs by investigating and analyzing the budget and the actual expenses of repair and maintenance of military facilities for the past 3 to 5 years, and then identifying the problems with these. To accomplish this, a theoretical review of previous studies and legal grounds related to repair and maintenance costs was performed, and data on the estimates and the actual expenses data used in BTL projects carried out by private companies were analyzed. First, one of the problems was that there are some items omitted, including consumables, and these items should be included in order to secure their budget. Second, in terms of the items for divided payments, two improvements had been presented: a short-term payment plan for the operation period of 3 to 5 years and a long-term payment plan for an additional and complemented period other than the operation period. The repair and maintenance costs should be further studied at the point of time in a future when the actual data on the costs and operation period of military facilities can be secured. This study is expected to serve as empirical data that will form the basis for a reasonable calculation of the construction cost for military facilities.