• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.10
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• pp.1291-1296
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• 2013

Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (POF) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RBI is to identify important failure modes and causes in the equipment. Once these are defined, the POF and COF can be assessed for each failure. During POF and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the POF is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided.

• Korean Journal of Health Education and Promotion
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• v.26 no.3
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• pp.25-34
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• 2009

Objectives: This study has longitudinally analyzed male smokers in order to find out the trend rate of re-smoking after smoking cessation. Methods: The study was conducted with 800 male smokers who were provided with smoking cessation services for 3 years at public health centers from July 16, 2005 to July 15, 2008. Results: The results can be summarized as follows: First, the success rate of smoking cessation for at least 6 months during 3-year period was 54.4%. The failure rate of smoking cessation at the second year was 47.5% and the third 27.2%, which indicates that the failure rate diminishes as the period of smoking cessation extends. Second, the success rate of smoking cessation at the first trial was 35.0%, the second 24.3%, and the third 16.4%. The success rate diminished as the number of trial increased. Third, the continuation rate of smoking cessation for a year was 18.3%, for 2 years 13.4%. For the success group, the continuation rate of smoking cessation for a year was 52.5%, for 2 years 38.2%. For the failure group, the rate for a year was 21.5%. Fourth, in this longitudinal analysis, the most crucial variables that affect the success rate of smoking cessation are total number of consultation and the past experience of successful smoking cessation. Conclusion: This study shows that success of smoking cessation and the continuance of smoking cessation are both difficult, and that the past experience of smoking cessation plays an important role determining the present success of smoking cessation and continuance of smoking cessation. Thus, it is necessary to divide people into success group and failure group based on the results of the past experience of smoking cessation when they consult at smoking cessation clinics at public health centers. Further, in order to increase the continuation rate of smoking cessation, this study suggests that we need to consider ways to take care of those who successfully abstained from smoking for 6 months.

• Journal of Genetic Medicine
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• v.11 no.2
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• pp.74-78
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• 2014

Sotos syndrome (SS, OMIM 117550) is characterized by prenatal and postnatal overgrowth with multiple congenital anomalies. However, there have been few cases of growth retardation caused by renal failure from infancy. We report a case of dysplasia of the bilateral kidneys with renal failure and poor postnatal growth. A 2-month-old boy visited the emergency room owing to poor oral intake and abdominal distension. He was born at the gestational age of 38 weeks with a birth weight of 4,180 g. After birth, he had feeding difficulty and abdominal distension. Upon physical examination, his height and weight were in less than the 3rd percentile, while his head circumference was in the 50th percentile on the growth curve. He also showed a broad and protruding forehead and high hairline. Blood laboratory tests showed severe azotemia; emergent hemodialysis was needed. Abdominal ultrasonography revealed bilateral renal dysplasia with multiple cysts and diffuse bladder wall thickening. A posterior urethral valve was suggested based on vesicoureterography and abdominal magnetic resonance findings. Results of a colon study to rule out congenital megacolon did not reveal any specific findings. The conventional karyotype of the patient was 46, XY. Array comparative genomic hybridization study revealed a chromosome 5q35 microdeletion including the NSD1 gene, based on which SS was diagnosed. We describe a case of SS presenting with end stage renal disease due to posterior urethral valve. The typical somatic overgrowth of SS in the postnatal period was not observed due to chronic renal failure that started in the neonatal period.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.2
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• pp.71-79
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• 2012

In this paper, an evaluation of a product replacement ratio of irreparable items to the normally working ones is performed with a view to a warranty analysis. It is demonstrated that the replacement ratio during the warranty period can be estimated from the field data collected during the period of operation, and one can provide the management with a useful information regarding the appropriateness for the warranty period, which is vital to the product marketing strategy. Although warranty data usually take the form of multiply right censored interval data, the conventional reliability analysis method seems to be good enough as in this case. More sophisticated method such as warranty cost analysis and 2-dimensional warranty analysis is yet desired.

• International Journal of Reliability and Applications
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• v.18 no.1
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• pp.9-20
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• 2017

In this paper, we consider a renewable repair-replacement warranty strategy with age-dependent minimal repair service and propose an optimal maintenance model during post-warranty period. Such model implements the repair time limit under warranty and follows with a certain form of system maintenance strategy when the warranty expires. The expected cost rate is investigated per unit time during the life period of the system as for the standard for optimality. Based on the cost design defined for each failure of the system, the expected cost rate is derived during the life period of the system, considering that a renewable minimal repair-replacement warranty strategy with the repair time limit is provided to the customer under warranty. When the warranty is finished, the maintenance of the system is the customer's responsibility. The life period of the system is defined and the expected cost rate is developed from the viewpoint of the customer's perspective. We obtain the optimal maintenance strategy during the maintenance period by minimizing such a cost rate after a warranty expires. Numerical examples using field data are shown to exemplify the application of the methodologies proposed in this paper.

• Journal of Astronomy and Space Sciences
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• v.28 no.2
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• pp.133-141
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• 2011

A satellite power system should generate and supply sufficient electric power to perform the satellite mission successfully during the satellite mission period, and it should be developed to be strong to the failure caused by the severe space environment. A satellite power system must have a high reliability with respect to failure. Since it cannot be repaired after launching, different from a ground system, the failures that may happen in space as well as the effect of the failures on the system should be considered in advance. However, it is difficult to use all the hardware to test the performance of the satellite power system to be developed in order to consider the failure mechanism of the electrical power system. Therefore, it is necessary to develop an accurate model for the main components of a power system and, based on that, to develop an accurate model for the entire power system. Through the power system modeling, the overall effect of failure on the main components of the power system can be considered and the protective design can be devised against the failure. In this study, to analyze the failure mode of the power system and the effects of the failure on the power system, we carried out modeling of the main power system components including the solar array regulator, and constituted the entire power system based on the modeling. Additionally, we investigated the effects of representative failures in the solar array regulator on the power system using the power system model.

• Radiation Oncology Journal
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• v.33 no.1
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• pp.29-35
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• 2015

Purpose: To analyze the prognostic factors for survivals and to evaluate the impact of postoperative whole pelvic radiotherapy (WPRT) on pelvic failure in patients with uterine sarcoma treated with radical surgery. Materials and Methods: We retrospectively analyzed 75 patients with uterine sarcoma who underwent radical surgery with (n = 22) or without (n = 53) radiotherapy between 1990 and 2010. There were 23 and 52 patients with carcinosarcoma and non-carcinosarcoma (leiomyosarcoma, 22; endometrial stromal sarcoma, 25; others, 5), respectively. The median follow-up period was 64 months (range, 17 to 269 months). Results: The 5-year overall survival (OS) and pelvic failure-free survival (PFFS) of total patients was 64.2% and 83.4%, respectively. Multivariate analysis revealed that mitotic count (p = 0.006) was a significant predictor of OS. However, factors were not found to be associated with PFFS. On analyzing each of the histologic subtypes separately, postoperative WPRT significantly reduced pelvic failure in patients with carcinosarcoma (10.0% vs. 53.7%; p = 0.046), but not in patients with non-carcinosarcoma (12.5% vs. 9.9%; p = 0.866). Among the patients with carcinosarcoma, 4 patients (17%) had recurrence within the pelvis and 3 patients (13%) had recurrence in other sites as an initial failure, whereas among the patients with non-carcinosarcoma, 3 patients (6%) experienced pelvic failure and 13 patients (25%) experienced distant failure. Conclusion: The most significant predictor of OS was mitotic count. Based on the improved PFFS after postoperative WPRT only in patients with carcinosarcoma and the difference in patterns of failure between histologic subtypes, optimal adjuvant treatment options should be offered to patients based on the risk of recurrence patterns.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.287-296
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• 2005

This experiments was designed to observe the effect of period and dose of ingestion of grapes on renal failure in dog. After the dogs had been mixed of general feed, raisins from U.S.A and fresh grapes from Chile selling in Korea. We observed the clinical sign, and analyzed the blood and urine using by biochemical test. The experiment was executed by the two following groups. The experiment group 1. derived renal failure by supplying the mixed general feed with fresh grapes and dry grapes 15 g per weight kg, 2 times a day (AM 09, PM 21), the experiment group 2. executed to derive renal failure by supplying the mixed general feed with fresh grapes and dry grapes 40 g per weight kg, 2 times a day. Extraction of blood for analysis was conducted one time a day and clinical test for renal failure was executed by means of a blood analysis, biochemical analysis, urine analysis, excretory urography (E.U) and E.R.D-$screen^{TM}$ urine test (Heska, USA). The results of group 1 were normal ranges (BUN 9.0~22.6 mg/dl, creatinine 0.8~1.2 mg/dl, Ca 9.7~12.3 mg/dl, Pi 2.9~4.6 mg/dl), renal failure was not observed. On the 3rd day in group 2, azotemia was arisen from the increasing BUN 83 mg/dl (7~25 mg/dl), creatinine 2.3 mg/dl (0.5~1.4 mg/dl), when executed urine was tested by E.R.D-$screen^{TM}$ test using in the early kidney disease diagnosis, microalbumine state was high positive, and it showed stale delay by using excretory urography (EU). This study demonstrated that acute renal failure by grapes and raisins dependent on food dose, and specific characters of individual.

• Journal of the Korean Chemical Society
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• v.66 no.2
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• pp.92-95
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• 2022

Failure Renal is the function of the kidneys to remove waste products and keep them on the periphery. and minerals for the body. Chronic renal failure is a syndrome characterized by a slow, irreversible deterioration of renal function due to the slow destruction of renal parenchyma. Calcium is one of the important minerals that the body contains in the blood and important tissues, and it has an important role in vital processes such as muscle contraction, nerve impulse conduction, the efficiency of heart muscle work, and blood clotting processes. The aim of the study is to study and compare calcium levels in men and women. It includes studying abnormal levels of calcium that cause many diseases, including chronic renal failure, and studying changes associated with renal failure. The method of this study was conducted on patients with chronic renal failure at Murjan Teaching Hospital in Babylon city during the period. The study included a sample of 70 patients (40 males, 30 females) with chronic renal failure, their ages ranged from 30-65, and 60 (30 males, 30 females) healthy without the disease of the same age. The result was a significant decrease in the number of red and white blood cells, hemoglobin concentration, hematocrit and platelets in patients with chronic renal failure, The result has been showed significant level in enzymes activity for transfer of amine group (alanine amino transferase, aspartate amino transferas) and phosphatase alkaline and also concentration of total bilirubin in patient with compare with healthy, Significantly increases, were found in the concentration of urea, uric acid and creatinine, as well as the concentration of calcium and phosphorous ions in the blood serum of patients compared to healthy controls.

• Hip & pelvis
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• v.35 no.3
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• pp.193-199
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• 2023

Purpose: Cephalomedullary (CM) nailing is widely performed in treatment of elderly patients with femoral intertrochanteric fractures. However, in cases of fixation failure, re-operation is usually necessary, thus determining factors that may contribute to fixation failure is important. In this study, we examined factors affecting the occurrence of fixation failure, such as age or fracture stability, after CM nailing in elderly patients. Materials and Methods: This study was conducted retrospectively using registered data. From April 2011 to December 2018, CM nailing was performed in 378 cases diagnosed with femoral intertrochanteric fractures, and 201 cases were finally registered. Cases involving patients who were bed-ridden before injury, who died from causes unrelated to surgery, and those with a follow-up period less than six months were excluded. Results: Fixation failure occurred in eight cases. Comparison of the surgical success and fixation failure group showed that the mean age was significantly higher in the fixation failure group compared with the control group (81.3±6.4 vs. 86.4±6.8; P=0.034). A significantly high proportion of unstable fractures was also observed (139/54 vs. 3/5; P=0.040), with a significantly high ratio of intramedullary reduction (176/17 vs. 5/3; P=0.034). A significantly higher ratio of unstable fractures compared with that of stable fractures was observed in the intramedullary reduction group (132/49 vs. 10/10; P=0.033). Conclusion: Fixation failure of CM nailing is likely to occur in patients who are elderly or have unstable fracture patterns. Thus, care should be taken in order to avoid intramedullary reduction.