• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.196-197
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• 2021

The underground method can be divided into Top-Down, Semi-Top-Down, Up-Up and Down-Up methods according to the construction order of the upper and lower structures. Among them, the Down-Up method proceeds with the construction of the first floor and its lower floors, and when the foundation is completed, the vertical members of the basement are sequentially completed from the foundation and the above-ground floor is constructed. In this paper, the crack reduction method around the open section of the Down-Up method affected by earth pressure was analyzed and divided into design and construction parts.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.1
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• pp.51-54
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• 2013

Purpose: The purpose of this study is to evaluate the difference between open reduction and internal fixation (ORIF) and intermaxillary fixation (IMF) of mandibular fractures. Methods: A total of one hundred twenty-seven patients who were treated for mandibular fractures at Chosun University Dental Hospital, from January 2008 to December 2010, and analyzed their prognoses based on the use of IMF at the time of fracture reduction. The patients were divided into two groups; the manual reduction group without IMF and IMF group. Results: After reduction of the mandibular fracture, good results were obtained with majority patients. Nonetheless, seven patients (13.0%) in manual reduction method without arch bars or IMF, developed complications after surgery. Three patients underwent IMF due to occlusal instability after surgery, while one patient underwent re-operation. Thus, a significant difference was not observed between the IMF and manual reduction groups. Conclusion: Manual reduction and IMF at mandibular simple fracture could produce good results. In case of mandibular simple fracture, it was recommended with only manual reduction without IMF or IMF during a short period.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.1
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• pp.169-174
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• 2005

The conventional harmonic filters to reduce zero harmonic current from neutral reactors and Zig-Zag connection, have several disadvantages of the decreased reduction rate of harmonics under a light load, because they have the load factor-dependent reduction rate of harmonics, and the risk of potential breaking in the neutral line by heated neutral reactor. Based Zig-Zag connection and Open-Delta mode, this new harmonic eliminating device (HANOS) adopts the combination of Zig-Zag connection and Open-Delta mode-the latter is additionally applied to the transformer's core block for connection to the neutral line. The results of this study demonstrated that the new device could eliminate safely zero harmonic current running in the neutral line without heating.

• Journal of Korean Foot and Ankle Society
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• v.24 no.1
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• pp.25-30
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• 2020

Purpose: Generally, the treatment of ankle trimalleolar open fractures is divided into two stages: external fixation and debridement; and secondary internal fixation. On the other hand, this two-stage operation takes considerable treatment time and is challenging in procedures requiring reduction. The purpose of this study was to evaluate the radiologic and clinical results of an immediate one-stage internal fixation operation considering the wound conditions to overcome two stage operation disadvantages. Materials and Methods: From September 2009 to January 2018, 24 cases of ankle trimalleolar open fractures, who underwent immediate internal fixation and were followed up for at least one year, were studied retrospectively. The open wound was divided into the Gustilo-Anderson classification. Open reduction and internal fixation were performed on every medial and lateral malleolar fracture. On the other hand, with posterior malleolar fractures, surgical or conservative treatment was performed depending on the fragment size. The radiologic outcome was evaluated using the Burwell and Charnley criteria and American Orthopaedic Foot and Ankle Society (AOFAS) scores, and complications, such as infection and posttraumatic arthritis, were used for the clinical evaluation. Results: The wound was classified into eight cases (33.3%) of type I, 11 cases (45.8%) of type II, and five cases (20.8%) of type IIIa. The degree of reduction was anatomical, fair, and poor in 16 cases (66.7%), six cases (25.0%), and two cases (8.3%), respectively. The mean AOFAS score was 79 points, and there were complications, such as infection in three cases (12.5%) and post-traumatic arthritis in two cases (8.3%). Conclusion: Satisfactory results were obtained through immediate surgical treatment in ankle trimalleolar open fractures of types I, II, and IIIa.

• Journal of Korean Foot and Ankle Society
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• v.1 no.1
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• pp.51-58
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• 1997

The purpose of this study is to evalute the efficacy af the Ilizarov external fixation for the surgical treatment. of the tibial plafond fractures. We reviewed retrospectively fourteen cases of tibial plafond fractures with moderate to severe soft. tissue damage, which were fixed with Ilizarov external fixator. Using the AO Muler classification, there were four Type C1 fractures, six Type C2 and four Type C3. In most, of the cases, the ankles were operated on with other associated fractures within a few days after injury. We reduced the fracture indirectly by soft issue taxis and fixed externally across the ankle joint. using the circular external fixator with tensioned wires and ankle hinge. In cases of inadequate closed reduction, we applied limited open reduction and internal fixation. Range of motion exercise began immediately. Postoperative follow-up averaged fourteen months (ranges, 8-30 months). Overall clinical results rated good or excellent in 7 cases, fair in 4 and poor in 3. There were three cases of pin tract infection which were resolved with short-term antibiotics and local care; one delayed wound closure in a patient. whose fracture was associated with Type III open wound; one wound slough in a patient associated with Type II open wound, which was closed later by skin graft; and one osteoarthritis. From this review, we concluded that cross-ankle circular external fixation with tensioned wires with or without. limited open reduction is a reasonable alternative for the treatment of the tibial plafond fractures with severe soft tissue damage.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.36 no.1
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• pp.30-36
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• 2014

There are many treatment options in management of mandibular condylar neck fractures. Closed reduction is the most conservative treatment; however, achievement of anatomic reduction is difficult, and there are some risks of mandibular functional impairment. Open anatomic reduction and internal fixation have some advantages; therefore, many oral and maxillofacial surgeons have attempted to achieve anatomic reduction through the open approach and extracorporeal reduction and fixation. However, when using this method, there is some risk of resorption of the fractured mandibular condylar head. Therefore, we designed a modified extracorporeal reduction technique, without detaching the lateral pterygoid muscle in order to maintain the blood supply to the fractured mandibular condylar head. We believe that this minor modification may minimize the risk of resorption of the fractured mandibular condylar head. In this article, we introduce this technique in detail, and report on two cases.

• Korean Security Journal
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• no.51
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• pp.199-219
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• 2017

This research examined the degree to which open-street closed-circuit television (CCTV) systems reduced crime in the vicinity of elementary schools. Information including crime dates, locations, and types around nine elementary schools in the city of Chuncheon in South Korea where the cameras had been installed was gathered and assessed. By employing the Poisson regression with "month" as the unit of analysis and controlling for the days in each month, the average monthly temperatures, and crime trends, the research results show that the CCTV installations had an impact on the reduction of total crime and serious crime. However, the same reduction effect was not observed for disorder crime. Therefore, the results of this study suggest that the employing CCTV is an effective way to control overall crime rates, especially serious crime.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.34 no.3
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• pp.388-397
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• 2008

The present study was performed to evaluate the function of the mandible according to the pattern of fracture and treatment methods of condylar fractures of the mandible and help operators in making a treatment plan. Sixty patients (average follow-up period was $7.8{\pm}9.4$ months) who were treated for condylar fracture from June, 2002 to May, 2006 at the Department of Oral and Maxillofacial surgery, Chonnam National University Hospital were reviewed. The common causes of the condylar fracture were traffic accident and fall-down (35.0%). In concomitant injuries, laceration was 46.7% and the fracture of the mandibular symphysis was highest incidence (60.0%). The common site of the fracture was the condylar head (47.8%), followed by subcondyle (36.2%) and condylar neck (15.9%). Under 15 years old patients, the closed reduction was performed in 87.5% out of the patients. All of the condylar fragments were fixed to the mandible with titanium miniplates in cases of open reduction. The mean period of intermaxillary fixation (IMF) was $14.2{\pm}6.5$ days in closed reduction and $10.0{\pm}4.2$ days in open reduction. The old patient with bilateral condylar head fractures, who were treated by closed reduction with IMF for 3 weeks, showed the limitation of mandibular movements. But, there was no significant different results between open reduction and closed reduction with the respect of the Helkimo's mandibular mobility index and clinical dysfunction index (DI). Complications, such as fibrous ankylosis and resorption of the mandibular condyle, were not observed in all patients. These results suggest that the good results can be obtained by closed reduction with proper IMF periods and functional exercise in most condylar fractures of the mandible except severely displaced extracapsular fractures.

• Journal of Korean Foot and Ankle Society
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• v.6 no.2
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• pp.208-210
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• 2002

We report a case of calcaneal tuberosity fracture, of which skin was at risk, treated urgently with limited open reduction and internal fixation, using 2 cannulated screws under local anesthesia.

• Journal of the Korean Arthroscopy Society
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• v.2 no.1
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• pp.93-96
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• 1998

We treated 10 cases of the medial malleolar fracture of the ankle by open reduction and internal fixation from June 1997 to December 1997. After the rigid internal fixation, we measured the gap of the fracture site and the step off of the articular surface by special instrument under the ankle arthroscopy whether it was reduced anatomically or not. And we tried to know the necessity of the arthroscopically assisted reduction and fixation in the medial malleolar fracture of the ankle. Under the arthroscopic view, all 10 cases were anatomically reduced as less than 1 mm of gap of the fracture site and less than 1mm of step off of the articular surface after open reduction and internal fixation in the medial malleolar fractures. In conclusion, through the arthroscopic management, it has advantage in finding and treating the accompanying intraarticular lesion, but also has disadvantage in setting the arthroscope and prolonging the operation time.