• 산업공학
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• 제12권1호
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• pp.132-142
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• 1999

Two-sided (left- and right-sided) assembly lines in practice can provide several advantages over one-sided lines in terms of the required line length, throughput time, cost of tools and fixtures, and so on. This paper considers two-sided assembly line balancing with the objective of minimizing line length. The balancing problem is more complicated than that of one-sided lines due to sequence-dependency of tasks assigned to a pair of directly facing workstations. This paper shows how genetic algorithm can be used to solve two-sided assembly line balancing. For this, an encoding and a decoding method suitable to the problem are presented. Proper genetic operators and an evalutation function are also employed. Extensive computational experiments are carried out to show the efficacy of the proposed algorithm. The results show that the algorithm is viable and promising in solution quality and computation time.

• 한국인터넷방송통신학회논문지
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• 제22권1호
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• pp.95-101
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• 2022

NP-난제로 알려진 양측 조립라인 균형문제는 주로 메타휴리스틱 방법들을 적용하여 해를 구하고 있다. 본 논문은 총 작업완료시간 W와 순환시간 c가 주어진 양측 조립라인의 선행순서도에서 좌측, 우측과 좌·우측 무관으로 공정들을 분류하고, 좌측과 우측 각각에 대해 M^* = ${\lceil}$W/c${\rceil}$개의 작업대에 T_i = c^* ± α < c, c^* = ${\lceil}$W/m^*${\rceil}$이 되도록 공정들을 할당하는 병렬군집 알고리즘을 제안하였다. 제안된 알고리즘을 4개의 실험데이터, 17개의 c에 적용한 결과, 기존의 메타휴리스틱 방법들에 비해 최소 작업대 수 m^*를 구하였으며, T_max < c로 순환시간을 단축하였다. 또한, 제안된 알고리즘은 휴리스틱 방법임에도 불구하고, 조립라인 효율성의 극대화와 작업자간 작업시간 편차를 최소화시킬 수 있었다.

• Radiation Oncology Journal
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• 제37권3호
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• pp.201-206
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• 2019

Purpose: To observe the effectiveness of the practical instruction sheet and the educational video for left-sided breast treatment in a patient receiving deep inspiration breath hold (DIBH) technique. Two parameters, simulation time and patient satisfaction, were assessed through the questionnaire. Methods: Two different approaches, which were the instruction sheet and educational video, were combinedly used to assist patients during DIBH procedures. The guideline was assigned at least 1 week before the simulation date. On the simulation day, patients would fill the questionnaire regarding their satisfaction with the DIBH instruction. The questionnaire was categorized into five levels: extremely satisfied to dissatisfied, sequentially. The patients were divided into four groups: not DIBH technique, DIBH without instruction materials, the DIBH with instruction sheet or educational video, and DIBH with both of instruction sheet and educational video. Results: Total number of 112 cases of left-sided breast cancer were analyzed. The simulation time during DIBH procedure significantly reduced when patients followed the instruction. There was no significant difference in simulation time on the DIBH procedures between patient compliance via instruction sheet or educational video or even following both of them. The excellent level was found at 4.6 ± 0.1 and 4.5 ± 0.1, for patients coaching via instruction sheet as well as on the educational video, respectively. Conclusion: Patient coaching before simulation could potentially reduce the lengthy time in the simulation process for DIBH technique. Practicing the DIBH technique before treatment is strongly advised.

• Journal of Digestive Cancer Reports
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• 제9권2호
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• pp.43-49
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• 2021

Background/Aims: Colonic stenting as a bridge to elective surgery is an alternative for emergency surgery in patients with acute malignant colonic obstruction. However, since its benefits are uncertain, we aimed to establish whether it has better clinical outcomes. Methods: The patients with acute malignant left-sided colon obstruction enrolled from January 2009 to December 2018 in National Health Insurance Service Ilsan Hospital. The patients were enrolled to undergo colonic stenting as a bridge to elective surgery or emergency surgery. The following oncological outcomes were assessed: incidence of complete remission, disease progression, local recurrence, and systemic recurrence. Results: Out of 40 patients, 33 received self-expanding metallic stent (SEMS) as a bridge-to-surgery, and 7 underwent emergency surgery. More stoma was made in case of emergency surgery with statistical significance (p < 0.001). There were no significant differences in complete remission rate in curable left-sided malignant colonic obstruction between SEMS as a bridge-to-surgery and emergency surgery. Complete remission was achieved for 3 patients (42.9%) in the non-stent group and 27 patients (81.8%) in the stent group. There was no statistically significant difference in oncologic outcomes between the two groups (p = 0.069). According to multi-variate analysis, advanced TNM stage, Adjuvant chemotherapy, and SEMS bridge-to-surgery were significantly associated with disease-free survival. Disease-free survival rate differed significantly between the two groups (p = 0.024). Conclusions: SEMS as a bridge-to-surgery might be an effective strategy and reduce stoma formation in acute malignant left-sided colon obstruction.

• 산업공학
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• 제10권2호
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• pp.29-40
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• 1997

This paper considers two-sided (left and right side) assembly lines which are often used, especially in assembling large-sized products such as trucks and buses. A large number of exact algorithms and heuristics have been proposed to balance one-sided lines. However, little attention has been paid to balancing two-sided assembly lines. This paper presents an efficient assignment rule for balancing two-sided assembly lines. The rule involves maximizing relatedness and slackness between works. We first investigate the characteristics of two-sided line balancing and devise new measures for the balancing. We in this rule assign workstations a set of tasks rather than an unit task at a time. a priority rule of assigning the sets is proposed. Extensive computational experiments are carried out to make the performance comparison between the proposed rule and existing ones. The computational results show that our rule is promising in solution quality.

• Journal of Chest Surgery
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• 제45권5호
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• pp.348-350
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• 2012

We herein report a very rare case of adult right-sided Bochdalek hernia accompanied with hepatic hypoplasia and inguinal hernia. A 29-year-old man was admitted with right-sided pneumothorax. A computed tomography was performed and revealed large right sided Bochdalek hernia with hepatic hypoplasia. Under thoracolaparotomy, the defect was closed with Gore-Tex soft tissue patch. After the operation, left-sided inguinal hernia was found. However, it turned out that it had been present during infancy and spontaneously resolved during adolescence. This is the first report of right-sided Bochdalek hernia with hepatic hypoplasia and inguinal hernia in an adult.

• Journal of Korean Neurosurgical Society
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• 제58권6호
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• pp.563-565
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• 2015

Juxtafacet cysts are implicated in neural compression. Thus far, it is known that surgical removal is the definitive treatment for symptomatic juxtafacet cyst because spontaneous regression is rare, and the failure rate of conservative treatment is high. We have reported a rare case of right-sided juxtafacet cyst development after the spontaneous resolution of contralateral left-sided facet cyst. The left-sided facet cyst resolved spontaneously without surgical treatment, but a juxtacyst developed on the contralateral facet on the right side, as illustrated on 4-year follow-up magnetic resonance images. To the best of our knowledge, this is the first report of newly developed contralateral juxtafacet cyst after spontaneous regression. Herein, we have discussed the natural history and the management of this rare case.

• 한국임상수의학회지
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• 제22권1호
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• pp.76-78
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• 2005

A 1 year 2 months old, male Chihuahua dog weighing 0.92 kg was presented with a history of intermittent vomiting after eating since two weeks ago. Based on the history, clinical signs, physical examination, and contrast radiographs, the diagnosis of sliding hiatal hernia was made. Diaphragmatic plication, esophagopexy and left-sided gastropexy concurrently required for surgical correction but in this case, diaphragmatic plication and esophagopexy could not be applied because of the patient's special condition. Instead, left-sided gastropexy was performed with additional pyloropexy. To treat reflux esophagitis, cimetidine and sucralfate were administrated and patient was fed in an upright position. Two days after the surgery, the patient showed normal activity and after then there was not found recurrence or complication.

• 호남수학학술지
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• 제41권3호
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• pp.449-461
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• 2019

The aim of this paper is to extend the concept of quasi and bi-ideals from left almost semigroups to left almost rings which are the generalization of one sided ideals. Further, we discuss quasi and bi-ideals in regular left almost rings and intra regular left almost rings. We then explore many interesting and elegant properties of quasi and bi-ideals.

• 대한안전경영과학회지
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• 제14권4호
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• pp.281-289
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• 2012

Recently, creative innovation has become a major topic in management innovation and due to this, various researches on its need and methodologies are being performed. According to previous studies on ambidexterity, explorative innovation is closer to divergent and right-sided brain, while exploitative innovation is closer to convergent and left-sided brain. Five attributes of the questionnaires were developed based on right-sided and left-sided brain theory. Also, 25 problem solving tools were selected according to previous studies. QC 7 Tools and new QC 7 Tools were frequently used in Six Sigma projects. Other 11 problem solving tools were selected with consideration on its usage frequency. Survey questionnaires were distributed to 25 Six Sigma consultants and 22 were retrieved for this study's use. As a result, 14 tools were identified to hold exploitative attribute while 11 tools were identified to hold explorative attributes.