• Maxillofacial Plastic and Reconstructive Surgery
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• v.23 no.3
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• pp.270-276
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• 2001

The treatment of mandibular subcondylar fractures is a matter of controversy. The majority of mandibular subcondylar fracture are treated by closed reduction, but the displaced or dislocated mandibular subcondylar fractures may be treated by open reduction. The characteristics of open reduction are the anatomical reduction, the functional restoration, the rapid function, the maintenance of vertical ramus dimension, the better appearance and the less resultant TMJ problem etc. When an open reduction is considered, the wire, miniplate, lag screw and Kirschner wire are available with internal fixation. Of these, Kirschner wire is a simple method relatively and correct positioning of the wire achieves rigid fixation. But many open reduction methods for mandibular subcondylar fractures require extraoral approach. The extraoral approach has some problems, the facial scar and the risk of facial nerve injury. On the other hand, the intraoral approach eliminates the potency of the facial scar and the facial nerve injury, but is difficult to access the operation site. Since the intraoral approach was first described by Silverman (1925), the intraoral approach to the mandibular condyle has been developed with modifications. The purpose of this article is to describe the intraoral technique with the Kirschner wire on mandibular subcondylar fractures. Conclusion : The intraoral reduction with Kirschner wire on mandubular subcondylar fractures avoids the facial scar and facial nerve injury and is simple method to the extraoral approach. And it has minimal morbidity and better esthetics.

• Journal of Technology Innovation
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• v.12 no.1
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• pp.219-240
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• 2004

As Shapiro and Varian argue the open approach generates bandwagon effects and facilitates the diffusion of a standard thanks to network externalities. However, the open approach is not linked automatically to economic benefits as suggested by some famous cases as the IBM PC history. On the contrary, the closed approach enables a tight control over a technology and its development, and insures the appropriation of economic benefits. As Shapiro and Varian suggest, a firm can also decide to mix an open approach with tight control over improvement or extentions. Patent pool is to offer fair, reasonable, nondiscriminatory access under a single license to patents that are essential for the use of standards-based or other platform technologies. patent pool offers only one license to everyone, Since each patent is essential, the royalty rate and thus the value is the same whether a licensee uses one or more patents.

• Journal of the Korean Society for Library and Information Science
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• v.54 no.3
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• pp.187-208
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• 2020

Open education is a worldwide movement to overcome educational barriers based on digital technology. It is necessary to discuss how to carry out the educational function of the library in the increasingly widespread open education environment. This study examines the concept and components of open education, and proposes an approach to how the library performs educational functions in an open education environment. The results of this study will serve as a guide in setting the role and direction for the library to become the subject of the implementation and spread of open education from the perspective of the library's educational function.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.44 no.2
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• pp.73-78
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• 2018

Objectives: The goal of this study was to evaluate the rates of complications, morbidity, and safety with the transparotid approach. Materials and Methods: A retrospective study was conducted and consisted of 53 surgically treated patients in the past five years for low condylar neck and subcondylar fractures. Only patients with malocclusion and who underwent open reduction with internal fixation with the retromandibular transparotid approach were included. The examined parameters were postoperative suboptimal occlusion, deflection, saliva fistula, and facial nerve weakness. Results: Fifty-three patients had an open reduction with internal fixation on 55 sides (41 males, 77.4%; mean age, 42 years [range, 18-72 years]). Four patients (7.5%) experienced transient facial nerve weakness of the marginal mandibular branch, but none was permanent. Four patients had a salivary fistula, and 5 patients showed postoperative malocclusion, where one needed repeat surgery after one year. One patient showed long-term deflection. No other complications were observed. Conclusion: The retromandibular transparotid approach is a safe procedure for open reduction and internal fixation of low condylar neck and subcondylar fractures, and it has minimal complications.

• Journal of Educational Research in Mathematics
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• v.8 no.1
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• pp.101-123
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• 1998

The purpose of this study is to construct the "open" instructional model that might be used properly in mathematics classroom. In this study, the core philosophy of "openness" in mathematics instruction is looked upon as the transference itself from pursuing simply strengthening the function of instruction such as effectiveness in the management of educational environment into the understanding of the nature of mathematics learning and the pursuing of true effectiveness in mathematics learning. It means, in other words, this study is going to accept the "openness" as functional readiness to open all the possibility among the conditions of educational environment for the purpose of realizing maximum learning effectiveness. With considering these concepts, this study regards open mathematics education as simply one section among the spectrum of mathematics education, thus could be included in the category of mathematics education. The model for open instruction in mathematics classroom, constructed in this study, has the following virtues: This model (1) suggests integrated view of open mathematics instruction that could adjust the individual and sporadic views recently constructed about open mathematics instruction; (2) could suggest structural approach for the construction of open mathematics instruction program; (3) could be used in other way as a method for evaluation open mathematics instruction program.thematics instruction program.

• The Journal of the Korean dental association
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• v.54 no.12
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• pp.1045-1054
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• 2016

Purpose : Aim of this study is to describe and compare clinical results and complications epending on the surgical approaches for the mandibular subcondyle fracture Materials and methods : The patients who had been diagnosed as the mandibular subcondyle fracture and underwent open reduction and internal fixation from May 2009 to December 2014 were included. They were divided into two groups depending on the surgical approaches; endoscopically assisted transoral approach and retromandibular approach. Association between the preoperative fracture classification and post-operative results was reviewed depending on the surgical approaches. Results : The number of patients selected in this study was 33. Eighteen patients (male 7, female 11) underwent open reduction and internal fixation via retromandibular approach and fifteen patients (male 12, female 3) underwent open reduction and internal fixation via endoscopically assisted transoral approach. The mean age, follow up period, and operation time were $44.29{\pm}15.19years$, $9.97{\pm}7.82months$, and $161{\pm}89.44minutes$. Post-operative results were all "good" state in the retromandibular approach group regardless of the fracture classification but two patients in the endoscopically assisted transoral approach group underwent re-operation due to "poor" results. The fracture types of two were classified as displacement and lateral override at the same time. There was no statistically significant difference between two groups. Three patients in the retromandibular approach group had experienced facial nerve palsy (17%) temporarily. No one showed malocclusion in this study. There was no significant difference on the complications such as temporomandibular disorder, local infection, and condyle resorption depending on the surgical approaches. Conclusion : In this study, there was no significant difference on the complications between the two groups but retromandibular approach has advantage over endoscopically assisted transoral approach in case of the severely displaced subcondyle fracture.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.293-298
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• 2010

Purpose: Since an injured elbow joint can disturb the activity of daily life by limiting motion, especially if the motion is restricted over 40 degree of flexion contracture and under 105 degree of further flexion, it is imperative to select the best method and the timing of treatment of the elbow stiffness. Therefore this review will discuss open surgical techniques for stiff elbows based on the literature. Materials and Methods: It is important to take sufficient clinical examination of the patient, including history taking. And, a surgeon should select appropriate procedure after accurately understanding about the status and cause of the stiff elbow with radiographic methods. Surgical methods include arthroscopic release open release, distraction arthroplasty, total elbow replacement and there are four approachs in the open release - anterior approach, medial "over the top" approach, limited lateral approach: column procedure, posterior extensile approach-. Results and Conclusion: Although at present the arthroscopic technique is emphasized for the treatment of elbow stiffness, a surgeon should know conventional open techniques.

• Journal of Gastric Cancer
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• v.13 no.1
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• pp.51-57
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• 2013

Purpose: Additional gastrectomy is needed after endoscopic resection for early gastric cancer when pathology confirms any possibility of lymph node metastasis or margin involvement. No studies depicted the optimal type of surgery to apply in these patients. We compared the short-term and long-term outcomes of laparoscopic gastrectomy with those of open gastrectomy after endoscopic resection to identify the optimal type of surgery. Materials and Methods: From 2003 to 2010, 110 consecutive patients who underwent gastrectomy with lymphadenectomy either by laparoscopic (n=74) or by open (n=36) for gastric cancer after endoscopic resection were retrospectively analyzed. Postoperative and oncological outcomes were compared according to types of surgical approach. Results: Clinicopathological characteristics were comparable between the two groups. Laparoscopic group showed significantly shorter time to gas passing and soft diet and hospital day than open group while operation time and rate of postoperative complications were comparable between the two groups. All specimens had negative margins regardless of types of approach. Mean number of retrieved lymph nodes did not differ significantly between the two groups. During the median follow-up of 47 months, there were no statistical differences in recurrence rate (1.4% for laparoscopic and 5.6% for open, P=0.25) and in overall (P=0.22) and disease-free survival (P=0.19) between the two groups. Type of approach was not an independent risk factor for recurrence and survival. Conclusions: Laparoscopic gastrectomy after endoscopic resection showed comparable oncologic outcomes to open approach while maintaining benefits of minimally invasive surgery. Thus, laparoscopic gastrectomy can be a treatment of choice for patients previously treated by endoscopic resection.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.87-104
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• 2005

Rock masses represent natural systems that are inherently complex and in which multiple mechanisms occur. Rock engineering systems such as tunnel and slope interact with surrounding systems through an exchange of both mass and energy. Accordingly the complex nature of rock masses calls for a system approach, and the open nature of rock engineering even requires the engineering to be controlled by a system approach for surrounding environments. However, traditional methods cannot take all variables and their interactions into account and are limited to the system with single mechanisms. Therefore, they are not proper for a complex and open system, and also cannot portray the whole system. Thus, a system approach is indispensable to rock engineering for dealing with the whole of a complex and open system. In this paper Mechanism Path Analysis Methodology (MPAM) Is Introduced for a system approach to rock engineering. The analysis by the methodology gives us all the information of systems behavior in the context of the whole system in order to accomplish the optimum design in accordance with the project objectives and analysis purposes. As an application a conventional model for the evaluation of TBM tunneling performance system is analyzed by MPAM and the result is compared with that by a traditional method.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.1
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• pp.79-86
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• 1989

The is a retrospective study on the transoral approach to open reduction of the Mandibular fractures. Our study was based on a series of 64 patients with mandibular fractures among 99 patients of facial bone fractures who had been treated by transoral approach with or without extraoral approach at Department of Oral and Maxillofacial Surgery, Yonsei Medical Center, Yonsei University from January 1981 to October 1988. We studied favorite sites of open reduction, fixation methods, results and prognosis related to transoral approaches of Mandibular fractures, and which compared with extraoral approaches. The results obtained are as follows : 1. The transoral open reduction was used more frequently in Mandibular fractures(64.6%) than Midfacial bone fractures(35.4%). Among 64 patients of mandibular fractures, 47 patients(73.4%) were treated only by transoral approach and others(26.6%) were treated by both trans- and extra-oral approach. Among 92 sites of mandibular fractures, 75 sites(81.5%) were treated by transoral approach and 17(18.5%) were treated by extraoral approach. 2. The most favorite site for transoral approach compared with extraoral approach was Symphysis(100%), and Angle(62.5%) was next in order of frequency on Mandibular fractures. 3. Direct Interosseous Wiring(DIW) was most commonly used for fixation(64.6%) and Miniplate osteosynthesis was used next in 28.1%. 4. Simple(39.1%) and Compound(52.2%) fractures were frequently indicated for transoral approach, however comminuted fractures were rarely indicated. 5. The direction of fracture lines on Angle of the mandible did not influence to determine whether transoral approach should be selected or not. However this area seemed to be more difficult to reduce exactly by transoral procedure than other areas because simultaneous superior and inferior fixation was applied predominantly on this area. 6. The success rate of reduction and fixation analyzed from us was more excellent in Direct Interosseous Wiring(29/53=54.7%) than in Rigid Internal Fixation(9/29=31.0%). But it might be depended upon various factors as like as sugeon's skill. 7. The postoperative complication due to transoral open reduction of mandible was not high(12.0%) and this rate was similar with other published reports.