• Journal of the Korean Operations Research and Management Science Society
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• 제17권1호
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• pp.41-41
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• 1992

In the real world situations that some jobs need be processed only on certain limited machines frequently occur due to the capacity restrictions of machines such as tools fixtures or material handling equipment. In this paper we consider n-job non-preemptive and m parallel machines scheduling problem having two machines group. The objective function is to minimize the sum of earliness and tardiness with different release times and due dates. The problem is formulated as a mixed integer programming problem. The problem is proved to be Np-complete. Thus a heuristic is developed to solve this problem. To illustrate its suitability and efficiency a proposed heuristic is compared with a genetic algorithm and tabu search for a large number of randomly generated test problems in ship engine assembly shop. Through the experimental results it is showed that the proposed algorithm yields good solutions efficiently.

• Journal of Trauma and Injury
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• 제27권2호
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• pp.13-19
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• 2014

Purpose: In general, X-ray examinations are not recommended for radial head subluxation (pulled elbow) patients. The purpose of this study was to determine the frequency of X-ray examinations and to investigate the factors associated with the decision to perform an X-ray examination on a patient with a pulled elbow. Methods: Patients who visited the pediatric emergency department (ED) of one tertiary hospital from January 1, 2011, to December 31, 2012, with a diagnosis of radial head subluxation at discharge were enrolled in this study. Through retrospective chart reviews, factors that could have influenced the decision to perform an X-ray examination and their statistical relevance were analyzed. Results: A total 308 patients were enrolled, and 101 patients (32.8%) underwent X-ray examinations. Among the 252 patients with a typical pulled elbow, 65 underwent X-ray examination. This result showed statistical significance compared to atypical pull-elbow group (25.8% vs. 64.3%, p<0.001). Factors associated with the decision to perform an X-ray examination were analyzed using the Chi-square test and the Fisher's exact test. The mechanism of injury and consultation with an orthopedic surgeon (p=0.001) showed statistical significance. In the multivariable logistic regression, the odds ratio (OR) for the injury mechanism was 4.7 (95% CI: 1.8~8.8, p<0.001) and that for consultation with an orthopedic surgeon was 8.0 (95% CI: 1.6~40.7, p=0.004). Conclusion: One third of patients with a pulled elbow underwent X-ray examination, and patients with an atypical mechanism of injury underwent more frequent X-ray examinations than did patients with a typical mechanism of injury. The factors that could have influenced the decision to perform an X-ray examination were mechanism of injury and consultation with an orthopedic surgeon.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제26권2호
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• pp.79-87
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• 2023

Purpose: Gastrointestinal (GI) endoscopy is an important tool for diagnosing and treating GI diseases in children. This study aimed to analyze the current GI endoscopy practice patterns among South Korean pediatric endoscopists. Methods: Twelve members of the Korean Society of Pediatric Gastroenterology, Hepatology and Nutrition developed a questionnaire. The questionnaire was emailed to pediatric gastroenterologists attending general and tertiary hospitals in South Korea. Results: The response rate was 86.7% (52/60), and 49 of the respondents (94.2%) were currently performing endoscopy. All respondents were performing esophagogastroduodenoscopy, and 43 (87.8%) were performing colonoscopy. Relatively rare procedures for children, such as double-balloon enteroscopy (DBE) (4.1%), endoscopic retrograde cholangiopancreatography (ERCP) (2.0%), and endoscopic ultrasound (EUS) (2.0%), were only performed by pediatric gastroenterologists at very few centers, but were performed by adult endoscopists in most of the centers; of all the respondents, 83.7% (41/49) performed emergency endoscopy. In most centers, the majority of the endoscopies were performed under sedation, with midazolam (100.0%) and ketamine (67.3%) as the most frequently used sedatives. Conclusion: While most pediatric GI endoscopists perform common GI endoscopic procedures, rare procedures, such as DBE, ERCP, and EUS, are only performed by pediatric gastroenterologists at very few centers, and by adult GI endoscopists at most of the centers. For such rare procedures, close communication and cooperation with adult GI endoscopists are required.

• Journal of Trauma and Injury
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• 제23권2호
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• pp.68-74
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• 2010

Purpose: The purpose of this study is, first, to analyze the risk factors that influence the severity of injury in pediatric multiple trauma patients and, second, to present solutions for the problems related to the treatment of such patients. Our living situations are so complicated that the danger of accidents is truly open to children who are not prepared. We need to draw attention to the increased numbers of various accidents involving children. Methods: We studied patients who visited the Emergency Medical Center at Chosun University Hospital from January 1, 2006, to December 31, 2008. Using medical records, we evaluated the general characteristics: the mechanism of injury, the vital signs, the revised trauma score (RTS), the injury severity score (ISS), and the hemoglibin value, which was checked at the time of visit, and the presence or the absence of emergent on regular surgery. We divided the level of injury as follows: light level (1-8 points), mid level (9-15 points), and serious level (above 16 points). We analyzed the medical data by using SPSS 17.0 for windows. Results: The average age of the patients examined was 8.6 years. The number of 6- to 11-year-old patients was 96, which was the largest, but the degree of injury severity was the highest among infant (0-2 years), according to ISS 7.95(${\pm}6.85$). The frequency of accidents was highest on sunny days, and most accidents occurred from 16:00 to 20:00. The cause of multiple trauma for children was the greatest in the traffic accident, (95 patients, 49.0%). In addition, the trauma caused by traffic accidents showed the highest ISS value ($9.02{\pm}6.42$) and the most serious degree (P=0.004). The ISS level of injury ($8.40{\pm}6.64$) for patients moved from a secondary hospital was higher than that ($6.49{\pm}5.57$) for patients who visited the medical center directly. The severity of injury was highest for patients who used a 119 ambulance ($8.84{\pm}5.80$). According to the injured parts of body, Injuries to the arms and the feet most frequent (79 patients, 40.7%), but the level of injury was the highest for internal organs and chest, $16.42{\pm}8.56$ and $11.23{\pm}6.97$, respectively. Conclusion: We used Abbreviated Injury Scale (AIS) in order to examine the characteristics by injured body part for pediatric multiple trauma patients. Because the degree of injury was the highest for internal organs or the chest, we need to more seriously examine and provide for patients who are suspected of having injuries to the internal organs or the chest. We need to quickly determine the need for surgery in patients with serious injuries to the arms and the feet, which is the greatest in frequency. In particular, we need to consider the surgical care of patients who are not very high in the severity of injury to their brains.

• Childhood Kidney Diseases
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• 제23권2호
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• pp.116-120
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• 2019

Bilateral renal obstruction is a rare critical condition, requiring a prompt diagnostic approach and treatment to restore the renal function. The most commonly observed obstructive uropathy in children is congenital malformation, such as posterior urethral valves and bilateral ureteropelvic junction obstruction. Malignant pelvic masses obstructing the ureter are widely reported in adults but are rarely observed in children. The treatment of ureteral obstruction related to pelvic malignancy is a therapeutic challenge with a median survival duration of 3-7 months in adults; however, pediatric patients with pelvic malignancy leading to ureteral obstruction had better outcomes, with a reported 5-year mortality rate of 20%, than the adult patients. Here, we report a rare case of bilateral ureteral obstruction associated with pelvic rhabdomyosarcoma presenting with acute kidney injury treated by ureteral diversion with double J stent, and concommittent emergency hemodialysis, leading to restoration of good renal function. We suggest that bilateral ureteral obstruction should be released as soon as possible using surgical or interventional approach to minimize the obstruction period, and subsequential chemotherapy may contribute to improvement of survival and recovery of renal function.

• Advances in pediatric surgery
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• 제13권1호
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• pp.45-51
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• 2007

Appendicitis is the most common surgical emergency in childhood and the technologic advances of modern medicine have affected the diagnosis and treatment of appendicitis. This study is to evaluate the differences in diagnosis and treatment of appendicitis between present and 10 year ago. The authors retrospectively reviewed the medical records of patients who underwent appendectomy under the diagnosis of the acute appendicitis from July 1993 to June 1995 (Group A, n = 78) and from July 2003 to June 2005 (Group B, n = 105). There are no differences between group A and B in mean age ($8.5{\pm}3.6$ vs. $9.3{\pm}3.1$ year), duration of symptoms ($3.0{\pm}3.2$ vs. $2.6{\pm}3.8$ days), and postoperative hospital stay ($6.6{\pm}4.8$ vs. $5.8{\pm}3.6$ days). Preoperative abdominal ultrasonogram and/or computed tomogram was performed in 7 patients (9.0 %) of group A and in 51 patients (58.5 %) of group B. Thirty-six patients (34.3 %) of group B underwent laparoscopic appendectomy, but none in group A. Incidence of a histologically normal appendix decreased from 15.8 % in group A to 4.8 % in group B (p =0.018). This study suggests that utilization of abdominal ultrasonogram or computed tomogram in preoperative evaluation become more popular and surgical treatment of acute appendicitis become more minimally invasive. The rate of negative appendectomy was also reduced compared with 10 year ago.

• Clinical and Experimental Pediatrics
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• 제62권3호
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• pp.90-94
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• 2019

Purpose: Several published policy statements have warned against the risks associated with trampoline use and recommended safety guidelines. However, few studies have focused on trampoline-related injuries in Korea. This study aimed to assess the incidence and characteristics of pediatric trampoline-related injuries presented to Ulsan University Hospital. Methods: We retrospectively reviewed the medical records of children aged <16 years with trampoline-related injuries who visited our Emergency Department between 2008 and 2017. Results: Over the 10-year period, 178 trampoline-related injuries were reported, which represented a significant increase (P=0.016). Most (87.6%) of the injuries occurred during the last 5 study years, and a rapid increase in injuries was observed in children aged <6 years. Lower extremity injuries (62.4%) were the most common, followed by injuries of the upper extremities, head and face, and trunk, including injuries to the neck and spine. Sixty-seven children (37.6%) had fractures, and proximal tibia fractures were the most common. Fractures were significantly more common in younger children (<6 years old) than in older children (P=0.026). Conclusion: In Korea, the mechanism of trampoline injury is similar to that of injuries incurred in indoor trampoline parks but is characterized by smaller spaces and multiple users. Trampoline use and the incidence of trampoline-related injuries in children aged <6 years are increasing rapidly. Prohibiting the use of trampolines for children aged <6 years, restricting simultaneous use by multiple children, and ensuring adult supervision should be strictly emphasized. Public awareness and policy guidelines are needed to reduce the incidence of trampoline-related injuries.

• Advances in pediatric surgery
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• 제10권1호
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• pp.60-62
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• 2004

Leveling colostomy with a frozen-section biopsy in a Hirschsprung's disease is an important factor for a successful procedure. Two neonatal cases of Hirschsprung's disease in the descending colon are reported. In both cases, loop ileostomy was established because of the unavailability of frozen-section biopsy on an emergency basis. At the time of definitive procedure of the first case, transition zone at the splenic flexure was noted and was compatible with the frozen section biopsy. In the second case, an unexpected longer resection at a higher level than transition zone was required because of the poor vascularity after dissection. In conclusion, a leveling colostomy should be selected as a choice in long-segment Hirschsprung's disease. Confirming preservation of the marginal artery of Drummond is particularly important in case of Hirschsprung's disease in the descending colon.

• Clinical and Experimental Pediatrics
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• 제63권9호
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• pp.345-354
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• 2020

The widespread and contagious coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 has become a burden in the global health domain. The subsequent discovery of the virus features and pathogenesis, and prompt and adequate management are still lacking and remain inconclusive. Children usually present milder symptoms than adults, and management focuses on providing symptomatic and respiratory supports. Several treatment modalities, including the utilization of mechanical ventilation (MV), antivirals, immune-modulating drugs, or other agents, may present promising results in reducing the symptoms of COVID-19, particularly in severe cases. Although no randomized clinical trials have been published to date, it is interesting to explore potential modalities for treating COVID-19 in children, based on review articles, case reports, and recent guidelines.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제18권4호
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• pp.280-285
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• 2015

Heterotopic pancreas (HP) is defined as pancreatic tissue lacking anatomic and vascular continuity with the main body of the pancreas. Most are asymptomatic, but can cause ulcer, bleeding, intussusception, and mechanical obstruction. Herein, we presented one case of HP presented as duodenal tumor causing duodenal obstruction. A 7-year-old girl visited the emergency room for abdominal pain with vomiting for 24 hours. Computed tomography and upper gastrointestinal series revealed a polypoid mass with short stalk in the 2nd portion of duodenum. We attempted an endoscopic removal. However, the lumen was nearly obstructed by the mass and the stalk was too broad and hard to excise. The mass was surgically removed via duodenotomy. It was confirmed as a HP with ductal and acini components (type 2 by Heinrich classification). Postoperatively, the patient has been well without any complication and recurrence.