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The Predictable Factors of the Postoperative Kyphotic Change of Sagittal Alignment of the Cervical Spine after the Laminoplasty

  • Lee, Jun Seok;Son, Dong Wuk;Lee, Su Hun;Kim, Dong Ha;Lee, Sang Weon;Song, Geun Sung
    • Journal of Korean Neurosurgical Society
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    • v.60 no.5
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    • pp.577-583
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    • 2017
  • Objective : Laminoplasty is an effective surgical method for treating cervical degenerative disease. However, postoperative complications such as kyphosis, restriction of neck motion, and instability are often reported. Despite sufficient preoperative lordosis, this procedure often aggravates the lordotic curve of the cervical spine and straightens cervical alignment. Hence, it is important to examine preoperative risk factors associated with postoperative kyphotic alignment changes. Our study aimed to investigate preoperative radiologic parameters associated with kyphotic deformity post laminoplasty. Methods : We retrospectively reviewed the medical records of 49 patients who underwent open door laminoplasty for cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL) at Pusan National University Yangsan Hospital between January 2011 and December 2015. Inclusion criteria were as follows : 1) preoperative diagnosis of OPLL or CSM, 2) no previous history of cervical spinal surgery, cervical trauma, tumor, or infection, 3) minimum of one-year follow-up post laminoplasty with proper radiologic examinations performed in outpatient clinics, and 4) cases showing C7 and T1 vertebral body in the preoperative cervical sagittal plane. The radiologic parameters examined included C2-C7 Cobb angles, T1 slope, C2-C7 sagittal vertical axis (SVA), range of motion (ROM) from C2-C7, segmental instability, and T2 signal change observed on magnetic resonance imaging (MRI). Clinical factors examined included preoperative modified Japanese Orthopedic Association scores, disease classification, duration of symptoms, and the range of operation levels. Results : Mean preoperative sagittal alignment was $13.01^{\circ}$ lordotic; $6.94^{\circ}$ lordotic postoperatively. Percentage of postoperative kyphosis was 80%. Patients were subdivided into two groups according to postoperative Cobb angle change; a control group (n=22) and kyphotic group (n=27). The kyphotic group consisted of patients with more than $5^{\circ}$ kyphotic angle change postoperatively. There were no differences in age, sex, C2-C7 Cobb angle, T1 slope, C2-C7 SVA, ROM from C2-C7, segmental instability, or T2 signal change. Multiple regression analysis revealed T1 slope had a strong relationship with postoperative cervical kyphosis. Likewise, correlation analysis revealed there was a statistical significance between T1 slope and postoperative Cobb angle change (p=0.035), and that there was a statistically significant relationship between T1 slope and C2-C7 SVA (p=0.001). Patients with higher preoperative T1 slope demonstrated loss of lordotic curvature postoperatively. Conclusion : Laminoplasty has a high probability of aggravating sagittal balance of the cervical spine. T1 slope is a good predictor of postoperative kyphotic changes of the cervical spine. Similarly, T1 slope is strongly correlated with C2-C7 SVA.

Spatial Integration of Multiple Data Sets regarding Geological Lineaments using Fuzzy Set Operation (퍼지집합연산을 통한 다중 지질학적 선구조 관련자료의 공간통합)

  • 이기원;지광훈
    • Korean Journal of Remote Sensing
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    • v.11 no.3
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    • pp.49-60
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    • 1995
  • Features of geological lineaments generally play an important role at the data interpretation concerned geological processes, mineral exploration or natural hazard risk estimation. However, there are intrinsically discordances between lineaments-related features extracted from surficial geological syrvey and those from satellite imagery;nevertheless, any data set contained those information should not be considred as less meaningful within their own task. For the purpose of effective utilization task of extracted lineaments, the mathematical scheme, based on fuzzy set theory, for practical integration of various types of rasterized data sets is studied. As a real application, the geological map named Homyeong sheet(1:50,000) and the Landset TM imageries covering same area were used, and then lineaments-related data sets such as lineaments on the geological map, lineaments extracted from a false-color image composite satellite, and major drainage pattern were utilized. For data fusion process, fuzzy membership functions of pixel values in each data set were experimentally assigned by percentile, and then fuzzy algebraic sum operator was tested. As a result, integrated lineaments by this well-known operator are regarded as newly-generated reasonable ones. Conclusively, it was thought that the implementation within available GISs, or the stand-alone module for general applications of this simple scheme can be utilized as an effective scheme can be utilized as an effective scheme for further studies for spatial integration task for providing decision-supporting information, or as a kind of spatial reasoning scheme.

The Study of Basic Direction and Successful Fixation Way for Enhancing Educational Capacity of General High School in Gyeongsangbuk-do (경상북도 일반고의 교육역량 제고를 위한 기본방향과 성공적인 정착방안 탐색)

  • Chung, Il-Hwan
    • Korean Journal of Comparative Education
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    • v.24 no.3
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    • pp.1-23
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    • 2014
  • The purpose of this study is to analyze some problems of general high school and provide some promotion ways of general high school in Gyeongsangbuk-do in long and short term perspective, considering necessity for consolidating educational capacity of general high school which is in disadvantage due to high school diversity and special high school promotion policy. For this, first, the study explores educational policy basis of Park Geun-hye's government, educational policy direction of Gyeongsangbuk-do, educational situation of general high school in Gyeongbuk area, and main contents of educational capacity consolidation way of general high school. Main tasks of Gyeongsangbuk-do general high school educational capacity reconsideration based on the educational capacity consolidation way of Ministry of Education are (1) enlargement of autonomy for formation and operation of focused curriculum by guidance, (2) enlargement of guidance and vocational education for general high school student, (3) consolidation of support program for student at risk, and (4) consolidation of support for general high school High-up program. For these main tasks are fixed and operated in school successfully, the fixation of school responsible management system based on geological environment and trait of each general high school, the application of whole quality control in school management, and the formation of cooperative school organizational culture should be constructed. And specific practice tasks and strategies for Gyeongsangbuk-do general high school educational capacity reconsideration (the cultivation of grobal democratic citizen, human being image in 2009 revised curriculum, and 'talented people with new thinking and genuine mind' of Gyeongsangbuk-do) are provided.

A safe, stable, and convenient three-dimensional device for high Le Fort I osteotomy

  • Sugahara, Keisuke;Koyachi, Masahide;Odaka, Kento;Matsunaga, Satoru;Katakura, Akira
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.42
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    • pp.32.1-32.4
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    • 2020
  • Background: Le Fort I osteotomy is a highly effective treatment for skeletal jaw deformities and is commonly performed. High Le Fort I osteotomy is a modified surgical procedure performed for improving the depression of the cheeks by setting the osteotomy higher than the conventional Le Fort I osteotomy. Developments in three-dimensional (3D) technology have popularized the use of 3D printers in various institutions, especially in orthognathic surgeries. In this study, we report a safe and inexpensive method of performing a high Le Fort I osteotomy using a novel 3D device and piezosurgery, which prevent tooth root injury without disturbing the operation field for patients with a short midface and long tooth roots. Results: A 17-year-old woman presented with facial asymmetry, mandibular protrusion, a short midface, and long tooth roots. We planned high Le Fort I osteotomy and bilateral sagittal split ramus osteotomy. Prevention of damage to the roots of the teeth and the infraorbital nerve and accurate determination of the posterior osteotomy line were crucial for clinical success. Le Fort I osteotomy using 3D devices has been reported previously but were particularly large in size for this case. Additionally, setting the fixing screw of the device was difficult, because of the risk of damage to the roots of the teeth. Therefore, a different surgical technique, other than the conventional Le Fort I osteotomy and 3D device, was required. The left and right parts of the 3D device were fabricated separately, to prevent any interference in the surgical field. Further, the 3D device was designed to accurately cover the bone surface from the piriform aperture to the infra-zygomatic crest with two fixation points (the anterior nasal spine and the piriform aperture), which ensured stabilization of the 3D device. The device is thin and does not interfere with the surgical field. Safe and accurate surgical performance is possible using this device and piezosurgery. The roots of the teeth and the infraorbital nerve were unharmed during the surgery. Conclusions: This device is considerably smaller than conventional devices and is a simple, low-cost, and efficient method for performing accurate high Le Fort I osteotomy.

The Effects of the Capital Adequacy and Liquidity Regulation on Internet Primary Banks (인터넷전문은행의 자본적정성과 유동성 규제에 관한 연구)

  • Bae, Jae Kwon
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.9 no.6
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    • pp.773-782
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    • 2019
  • Basel III (Third Basel Accord or Basel Standards) is a global, voluntary regulatory framework on bank capital adequacy, stress testing, and market liquidity risk. Basel III regulatory ratios include capital adequacy, asset soundness, and liquidity. The capital adequacy variables include BIS capital adequacy ratio, BIS tier 1 capital ratio, and tangible common equity ratio. The asset soundness variables include non-performing loan ratio and non-performing loan coverage ratio. The liquidity regulation variables include KRW liquidity coverage ratio and foreign currency liquidity coverage ratio. This study aims to investigate how capital adequacy standard affects efficiency of internet primary banks. As a result of this study, BIS capital adequacy ratio of domestic internet primary banks is lower than that of commercial banks. In order to maintain sustainable operation considering capital adequacy regulations, it is necessary to expand additional capital. In addition, the delinquency rate and non-performing loan ratio of domestic internet primary banks is gradually increasing due to the maturity of high-yield loans in 2019.

Fistula Formation Between the Disc and Dura after Percutaneous Endoscopic Lumbar Discectomy - A Case Report - (경피적 내시경 요추 추간판 절제술 후 발생한 추간판과 경막 사이의 누공 형성 - 증례 보고 -)

  • Kim, Hak Sun;Kim, Hyoung Bok;Chung, Hoon-Jae;Yang, Jea Ho
    • Journal of Korean Society of Spine Surgery
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    • v.25 no.4
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    • pp.180-184
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    • 2018
  • Study Design: Case report Objectives: To document fistula formation between the disc and dura by an unrecognized dural tear after percutaneous endoscopic lumbar discectomy (PELD). Summary of Literature Review: The risk of durotomy is relatively low with PELD, but cases of unrecognized durotomies have been reported. An effective diagnostic tool for such situations has not yet been identified. Materials and Methods: A patient twice underwent transforaminal PELD under the diagnosis of a herniated lumbar disc at L4-5. She still complained of intractable pain and motor weakness around the left lower extremity at 6 months postoperatively. Magnetic resonance imaging showed no specific findings suggestive of violation of the nerve root. However, L5 and S1 nerve root injury was noted on electromyography. An exploratory operation was planned to characterize damage to the neural structures. Results: In the exploration, a dural tear was found at the previous operative site, along with a fistula between the disc and dura was also found at the dural tear site. The durotomy site was located on the ventrolateral side of the dura and measured approximately 5 mm. The durotomy site was repaired with Nylon 5-0 and adhesive sealants. The patient's preoperative symptoms diminished considerably. Conclusions: Fistula formation between the disc and dura can be caused by an unrecognized dural tear after PELD. Discography is a reliable diagnostic tool for fistulas formed by an unrecognized durotomy.

Empirical Study on Injury Management System of Fire-Fighting Officer (소방공무원의 공상관리제도에 대한 실증연구)

  • Kwon, Seol A;Oh, Myeong Keun;Lee, Ju Ho;Lee, Min-Kyu;Park, Sang Ho;Hyeon, Seung Hyo;Ryu, Sang Il
    • The Journal of the Korea Contents Association
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    • v.19 no.3
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    • pp.114-125
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    • 2019
  • The frequency of official injury of fire-fighting officers exposed to an extreme situation in disaster areas has been continuously increased. In spite of increase of injury, procedures of injury approval are complex, so the working environment of fire-fighting officers is very poor in terms of safety management. This study was, therefore, conducted to provide basic data for improvement of the injury management system for fire-fighting officers, by empirically analyzing the system for those in Busan city. The findings of the empirical analysis are as follows: first, the frequency of injury experienced by them is higher than that of other occupations; second, application for injury is not actively made; third, fire-fighting officers should bear the expense if injury is approved. On the basis of such an analysis on actual conditions, an analysis on policy factors for improving the injury management system shows; first, various high-risk matters should be considered in the review of application for injury, for improvement factors of the application for injury, while it is necessary to extend the benefit and support project for injured officers, for operation improvement factors of the injury management system, and the compensation act should be improved, for the improvement factors of the injury system. Second, it is urgent to develop damage prevention and coping education program for improving the injury management system. In addition, the simplification of administrative procedures of application for injury and the extension of benefit and support project for injured officers should be realized as soon as possible, moreover, the enhancement of directors' interest and support is also required.

Optimum Evacuation Route Calculation Using AI Q-Learning (AI기법의 Q-Learning을 이용한 최적 퇴선 경로 산출 연구)

  • Kim, Won-Ouk;Kim, Dae-Hee;Youn, Dae-Gwun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.7
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    • pp.870-874
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    • 2018
  • In the worst maritime accidents, people should abandon ship, but ship structures are narrow and complex and operation takes place on rough seas, so escape is not easy. In particular, passengers on cruise ships are untrained and varied, making evacuation prospects worse. In such a case, the evacuation management of the crew plays a very important role. If a rescuer enters a ship at distress and conducts rescue activities, which zones represent the most effective entry should be examined. Generally, crew and rescuers take the shortest route, but if an accident occurs along the shortest route, it is necessary to select the second-best alternative. To solve this situation, this study aims to calculate evacuation routes using Q-Learning of Reinforcement Learning, which is a machine learning technique. Reinforcement learning is one of the most important functions of artificial intelligence and is currently used in many fields. Most evacuation analysis programs developed so far use the shortest path search method. For this reason, this study explored optimal paths using reinforcement learning. In the future, machine learning techniques will be applicable to various marine-related industries for such purposes as the selection of optimal routes for autonomous vessels and risk avoidance.

Investigation on Enhancing Efficiency in International Cooperation for Climate Change Adaptation of Republic of Korea (우리나라의 기후변화적응 국제협력에 대한 고찰)

  • Park, Yong-Ha;Chung, Suh-Yong;Son, Yowhan;Lee, Woo-Kyun
    • Journal of Climate Change Research
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    • v.1 no.2
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    • pp.179-188
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    • 2010
  • To cope with various issues in the aspect of climate change adaptation of UNFCCC, Korea began preparing a Five-year National Climate Change Adaptation Plan in 2010 to be implemented from 2011~2015, for the purposes of securing a concrete system to adapt to climate change. Compared with the policies and measurement tools of developed countries, Korea's climate change adaptation capabilities suffers from a number of limitations including insufficiencies of basic information, human resources for research on climate change, and technology in risk and vulnerability assessment. At the same time, Korea maintains superior information technology systems, and comparatively strong climate change adaptation technologies. Recently, with the establishment of the Korea Adaptation Center for Climate Change as a specialized research organization in climate change adaptation, Korea has upgraded its ability to adapt to climate change and to provide support to other Asian countries which are vulnerable to climate change. In consideration of the close relation between climate change adaptation policy and technology development with the environmental industry, Korea's pursuit of cooperation and technical support for developing countries in the Asia region can be seen as the commencement of a long term investment for the nation's future. International cooperation on climate change adaptation between countries in the region can build a mutually complementary and integrated partnership in business, research, education, and other areas. Furthermore, Korea can also participate in the exploration of common issues as landmark projects that can attract global interest with developing countries.

Investigations of Vulnerable Members and Collapse Risk for System Support Based on Damage Scenarios (손상시나리오 기반 시스템 동바리 취약부재 도출 및 붕괴 위험성 분석)

  • Park, Sae In;Park, Ju-Hyun;An, Hyojoon;Lee, Jong-Han
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.1
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    • pp.33-40
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    • 2021
  • In recent years, many construction projects become large and complicated, and construction accidents also steadily increase, which grows interest in the safety and maintenance during construction. Many of the construction accidents are related to temporary construction and structures, but the safety evaluation and management during construction are unclear and indefinite due to the short operating period and continuous change in the formation of the temporary structure. The system support, which is one of the temporary structures to support the pouring load of concrete, was proposed to easily install and dismantle members with connection parts pre-manufactured. The use of the system support is increasing to improve the safety of the temporary structure during construction. However, the system support, which consists of multiple members, still has uncertainties in connectivity between members and supports of vertical members. Therefore, this study analyzed the structure, load, and accident cases of the system support to define the damage scenarios for member connection, support condition, and lateral displacement. The decrease rate of the critical load was analyzed according to the damage scenarios based on the defined unit structure of the system support. In addition, this study provided vulnerable members for each damage scenario, which could induce instability of the temporary structures during design, construction, and operation of the structure.