• Proceedings of the KIEE Conference
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• 1985.07a
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• pp.26-28
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• 1985

The open delta circuit of the power transformer is still often applied, in spite of its reduced utilization of the power. In this paper, a new approach to the calculation of the power and its distribution in each transformer component is presented. For the power evaluation, the method of the complex power analysis is applied.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.5
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• pp.474-481
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• 2006

The endoscopic assisted approach for the treatment of condylar fracture is a less invasive alternative treatment modality and is considered to be able to overcome the limited access to the operation field to obtain an accurate reduction and fixation. Six patients with condylar neck and subcondylar fracture underwent the endoscopic assisted open reduction and internal fixation through the transoral approach at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. The endoscope was inserted through an intraoral incision and the reduction of fracture fragment was performed via a transbuccal approach with two transcutaneous stab incisions. Five patients showed anatomic reduction without any complications. One patient, whose fracture site was fixed with a single plate, showed displacement of fractured condylar segment during the follow up period. No patient had any facial nerve damage.

• Journal of Environmental Policy
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• v.5 no.4
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• pp.85-105
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• 2006

This article aims to conserve greenbelts by adopting the national trust approach. This article reviews the current issues and problems in managing greenbelts in Korea. And this article redefines the function of greenbelts, and then suggests the new principles of management strategies of greenbelts. Greenbelts is to provide green open space for urban residents and to contain urban sprawl not to reserve lands for the future urban development. This article proposes basic principles for the effective management of green belts. They include (1) preserving environmental value, (2) maximizing public access to open space and environment resources, and (3) enhancing public-participation and collaboration among different groups and organizations for the management of greenbelts. These principles are closely related to those of national trust movement. This article suggests the government to adopt national trust approach (organization, funding, site selection criteria, legislation) to improve the environmental-friendly conservation and management of greenbelts in Korea.

• Journal of the Korea Society of Computer and Information
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• v.26 no.9
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• pp.13-25
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• 2021

In the age of digital innovation based on the Internet, Information and Communication and Artificial Intelligence technologies, huge amounts of datasets are being generated, collected, accumulated, and opened on the web by various public institutions providing useful and public information. In order to analyse, gain useful insights and information from data, Formal Concept Analysis(FCA) has been successfully used for analyzing, classifying, clustering and visualizing data based on the binary relation between objects and attributes in the dataset. In this paper, we present an approach for enhancing the analysis of relational attributes of data within the extended framework of FCA, which is designed to classify, conceptualize and visualize sets of objects described not only by attributes but also by relations between these objects. By using the proposed tool, RCA wizard, several experiments carried out on some public open datasets demonstrate the validity and usability of our approach on generating and visualizing conceptual hierarchies for extracting more useful knowledge from datasets. The proposed approach can be used as an useful tool for effective data analysis, classifying, clustering, visualization and exploration.

• Journal of Gastric Cancer
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• v.24 no.2
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• pp.210-219
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• 2024

Purpose: The study aimed to investigate real-world surgical outcomes of minimally invasive surgery (MIS) for advanced gastric cancer using Korean Gastric Cancer Association (KGCA)-led nationwide data. Materials and Methods: A nationwide survey of patients who underwent surgical treatment for gastric cancer in 2019 was conducted by the KGCA. A total of 14,076 patients from 68 institutions underwent surgery, and 4,953 patients diagnosed with pathological stages IB-III gastric cancer were included. Among them, 1,689 patients who underwent MIS (MIS group) and 1,689 who underwent the open approach (open group) were matched using propensity score in a 1:1 ratio. Surgical outcomes were compared, and multivariate analysis was performed to identify the independent factors for overall morbidity. Results: The MIS group had a lower proportion of D2 lymphadenectomy, total omentectomy, and combined resection. However, the number of harvested lymph nodes was higher in the MIS group. Better surgical outcomes, including less blood loss and shorter hospital stay, were observed in the MIS group, and the overall morbidity rate was significantly lower in the MIS group (17.5% vs. 21.9%, P=0.001). The mortality rates did not differ significantly between the 2 groups. In the multivariate analysis, the minimally invasive approach was a significant protective factor against overall morbidity (odds ratio, 0.799; P=0.006). Conclusions: Based on the Korean nationwide data, MIS for stage IB-III gastric cancer had better short-term outcomes than the open approach, including lower rates of wound complications, intra-abdominal abscesses, and cardiac problems.

• Korean Institute of Interior Design Journal
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• v.13 no.3
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• pp.35-42
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• 2004

This study dealt with approaches in architecture and music in the contemporary situation characterized by accidence and uncertainty through Pierre Boulez and Rem Koolhaas' works. First of all, we examined basic positions with starting from zero degree breaking from fixed ideas and with relative neutrality. Then, from a methodological aspect, we inquired into 1) anti-hierarchical objective approach, 2) accidental approach to form. 3) diagram of structure and event, and 4) the use of selective routes. Lastly, from a receptive aspect, we dealt with the space of pluralistic perspective and works in progress. The two persons used chaosmos approach that enables adjustment and control through structure defining the relationship with accidence or chaos. With the approach, they created works in progress or open works that have a pluralistic viewpoint working in the field of specific relation and the concept of endless regeneration.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.47 no.4
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• pp.327-334
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• 2021

A transparotid approach, with a retromandibular or preauricular incision, is an alternative surgical approach for treating a subcondylar fracture and reducing the potential for complications such as injury to the facial nerves. However, retromandibular and preauricular incisions are both created far away from the parotid gland-dissection area. Thus, it is necessary to undermine the skin and retract it anteriorly to access the surgical field. Here, we introduce a modified approach wherein the incision allows for direct access to the fracture site. This approach may be adopted to shorten the incision length, reduce the retraction trauma at the surgical site, and help prevent injury to the facial nerve.

• Journal of Korean Neurosurgical Society
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• v.39 no.6
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• pp.413-418
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• 2006

Objective : The objective of this study is to evaluate and compare the clinical results between classical open surgery and percutaneous endoscopic lumbar discectomy[PELD] in cases of extraforaminal lumbar disc herniation. Methods : We obtained the clinical data from 47 patients with extraforaminal lumbar disc herniations who underwent the open paramedian muscle-splitting approach or percutaneous endoscopic lumbar discectomy[PELD] between January 2001 and February 2004. This study consisted of patients with soft disc extraforaminal herniations. The patients were assessed with the visual analogue scale[VAS] and MacNab's criteria before surgery, just before discharge, and postoperative 1 year. Results : There were 25 cases in the open surgery group and 22 cases in the PELD group. The average operating time was $78{\pm}36.71\;min$ in the PELD group and $110{\pm}29.68\;min$ in the open surgery group. The mean hospital stay was $2.73{\pm}2.62$ days in the PELD group and $7.68{\pm}2.59$ days in the open surgery group. VAS decreased from $8.34{\pm}0.66$ to $1.29{\pm}2.27$ in the PELD group and from $8.40{\pm}1.40$ to $1.70{\pm}1.72$ in the open surgery group at the one-year follow-up. The success rate of PELD was 86.4%, compared with 80.0% for open surgery. However, there were no statistically significant difference between two groups for success rate and VAS. Conclusion : Although the success rates were similar in both groups, PELD is less invasive, faster, and safe procedure than open surgery for extraforaminal disc herniation in selected patients.

• Clinics in Shoulder and Elbow
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• v.27 no.2
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• pp.212-218
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• 2024

Background: Rotator cuff tears commonly cause shoulder pain and functional impairment, prompting surgical intervention such as mini-open and arthroscopic methods, each with distinct benefits. This study aimed to compare the clinical outcomes and complications of these two approaches. Methods: A retrospective analysis was conducted on 165 patients who underwent rotator cuff repair using either arthroscopic-assisted mini-open or full arthroscopic approaches. Patient demographics, tear characteristics, clinical outcomes, and complications were assessed, with statistical analyses conducted to discern differences between the groups. Results: Among the patients, 74 (53.2%) received the mini-open approach, while 65 (46.8%) underwent arthroscopic repair, with a mean follow-up of 19.91 months. The mini-open group exhibited significantly higher postoperative American Shoulder and Elbow Surgeons (ASES) scores compared to the arthroscopic group (P=0.002). Additionally, the mini-open group demonstrated a more significant improvement in ASES scores from preoperative to postoperative assessments (P=0.001). However, the arthroscopic method had a significantly longer operative time (P<0.001). Complications, including anchor placement issues, frozen shoulder, infection, and re-rupture, occurred in 17.3% of patients overall. Re-rupture rates were 13.5% for mini-open and 6.2% for full arthroscopic repair, with no significant difference between the two methods (P=0.317). Conclusions: Both the mini-open and arthroscopic methods yielded favorable clinical outcomes for rotator cuff tear treatment, but the mini-open group exhibited superior results. Surgeons should consider patient characteristics, tear attributes, and surgical expertise when selecting the appropriate technique.

• Journal of Korean Foot and Ankle Society
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• v.11 no.1
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• pp.79-85
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• 2007

Purpose: To evaluate the clinical efficacy of the limited posterior approach for the surgical treatment of intraarticular fracture of calcaneus. Materials and Methods: From March 2000 to February 2006, we studied retrospectively 186 patients, 203 cases who were treated with open reduction and internal fixation through limited posterior approach and were followed up for more than 1 year. The clinical results were evaluated with Creighton-Nebraska score and circle draw test after 1 year. We checked simple AP, lateral, axial and Broden's view preoperatively and 1 year after surgery, and compared $B{\ddot{o}}hler$ angle and Gissane angle. Results: By Creighton-Nebraska score, Sanders type 2 was 86.4, type 3 was 74.3, type 4 was 62.4. And by circle draw test, type 2 was 8.9 cm, type 3 was 7.2 cm, type 4 was 5.9 cm. $B{\ddot{o}}hler$ angle and Gissane angle were $7.6^{\circ}$, $102.4^{\circ}$, and it increased to $23.5^{\circ}$, $128.6^{\circ}$ after postoperative 1 year. Conclusion: Limited posterior approach for the surgical treatment of intraarticular fracture of calcaneus was considered to an effective treatment modality.