• Journal of the Korea Convergence Society
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• 제12권8호
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• pp.31-37
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• 2021

As the size of buildings increases due to urbanization due to the development of industry, the need to purify the air and maintain a comfortable indoor environment is also increasing. With the development of monitoring technology for refrigeration systems, it has become possible to manage the amount of electricity consumed in buildings. In particular, refrigeration systems account for about 40% of power consumption in commercial buildings. Therefore, in order to develop the refrigeration system failure diagnosis algorithm in this study, the purpose of this study was to understand the structure of the refrigeration system, collect and analyze data generated during the operation of the refrigeration system, and quickly detect and classify failure situations with various types and severity . In particular, in order to improve the classification accuracy of failure types that are difficult to classify, a three-step diagnosis and classification algorithm was developed and proposed. A model based on SVM and LGBM was presented as a classification model suitable for each stage after a number of experiments and hyper-parameter optimization process. In this study, the characteristics affecting failure were preserved as much as possible, and all failure types, including refrigerant-related failures, which had been difficult in previous studies, were derived with excellent results.

• The Journal of the Korean dental association
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• 제49권8호
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• pp.451-460
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• 2011

Dental caries has been widely prevalent with presence of cavitation on teeth. For the last several decades, the prevalence of dental caries in developed countries has rapidly decreased so there has been needed a new and detailed diagnostic guideline to differentiate the severity of dental caries, especially for early status of caries. The cariology specifically requires the development of an integrated definition of dental caries and uniform systems for measuring the caries process in the fields of clinical diagnosis and treatment, epidemiological researches, and dental education and so forth. The international Caries Detection and Assessment System (ICDAS) optically measures the enamel surface changes and potential histological depth of carious lesions by relying on surface characteristics of teeth. ICDAS is a visual classification system that was developed to diagnose the subtle changes of enamel surface, predict the progress direction of early caries, allow standardized data collection in relation to caries in different settings, and to enable better comparison of oral health between countries worldwide and research studies.

• Journal of the Korean Society for Aviation and Aeronautics
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• 제24권2호
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• pp.59-67
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• 2016

The checklist currently used for Aviation safety inspection performed by ASIs consists of inspection groups and multiple items, it does not have structured hierarchy system which required to efficiently process aviation safety analysis. On this study, through mapping taxonomy of HFACS onto current checklist to secure structured hierarchy system and present a specification on systematic frequency and severity to perform safety risk assessment of detected hazard.

• Journal of Chest Surgery
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• 제23권1호
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• pp.152-157
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• 1990

A clinical study for thymectomy for 23 patients in Myasthenia Gravis was done between May, 1982 and July, 1989. at the department of Thoracic and Cardiovascular Surgery, College of Medicine, Han Yang University. Among Z3 patients, male to female ratio was 11: 12 and Age of onset was ranged from 15 years-old to 52 years-old. Previous symptom duration from diagnosis until operation was ranged from 2 months to 96 months, and Mean duration was 28.74 months. The severity of disease was classified by Osserman`s classification preoperatively. In histopathology of thymus, Thymic hyperplasia 7 cases, Thymoma 7 cases, Invasive thymoma 3 cases, Within Normal Limit 5 cases, and Thymic Atrophy 1 case. Correlation between preoperative symptom duration and postoperative clinical course was statistically significant. The shorter of preoperative symptom duration, The better of postoperative clinical course. Grading of postoperative course was classified by Papatestas in 1975. Follow-up for postoperative course was ranged from 3 months to 7 year and 4 months, Cases of complete remission 1 year postoperative period were 9 cases and cases of Improvement were 8 cases, So totally 17 cases among 23 cases[73.91%] found good results.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.873-878
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• 2005

본 연구에서는 과거 우리나라의 농업가뭄 피해와 기상상황 등을 조사하고, 기왕의 가뭄지수들을 검토하여 우리나라 실정에 맞는 농업가뭄지표를 개발하고, 농업가뭄의 평가를 위한 가뭄심도 분류 기준을 설정하였다. 기존의 농업가뭄의 평가를 위해서 주요 가뭄년에 대한 한해극복지를 수집하였고, 주요 일간지를 대상으로 가뭄기록을 조사하였다. 이를 바탕으로 시기별 농업가뭄의 발생에 대한 정량적 분석을 위한 분석기준을 선정하여 각 연도별 발생상황을 정량화하였다. 국내외에서 가뭄을 평가하기 위해 많이 쓰이는 PDSI, SPI, Percent of Normal, Decile, Percent of Median을 이용하여 가뭄지수를 산정하였고, 가뭄지수 산정결과와 기록된 가뭄 발생결과와 비교하여 각 지수별 정확도를 평가한 결과, 우리나라의 농업가뭄 발생에 대해서는 가뭄의 발생시기와 가뭄지속에 대해서는 3개월 지체된 SPI가 잘 맞는 것으로 나타났다. 또한 농업가뭄지표의 실용화를 통한 가뭄대책업무를 위해 평시대비, 가뭄우려, 가뭄확산으로 구분된 가뭄단계를 세분하여 평년강우지수(MRI), 표준강우지수(SPI), 무강우지수(DDI), 저수율 및 토양수분상태를 고려하도록 가뭄단계를 6단계로 세분하여 설정하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 대한산업공학회/한국경영과학회 2000년도 춘계공동학술대회 논문집
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• pp.597-600
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• 2000

계속적인 증가 추세를 보이고 있는 교통량으로 인해 환경 문제뿐 아니라 교통사고로 인한 사상자 및 물적피해가 상당량으로 집계되고 있다. 본 논문에서는 데이터융합 및 앙상블 클러스터링방법을 이용한 교통사고 심각도 분류분석방법을 제안함으로서 교통사고예방에 기여하고자 한다. 이를 위하여 신경망과 Decision-Tree기법을 이용하여 얻은 물적피해와 신체상해가 발생할 확률을 융합하는 전형적인 데이터 융합기법(템스터-쉐퍼, 베이지안 방법, 로지스틱융합방법)을 사용하였다. 또한, 분류정확도를 향상시키고자 Bootstrap 재추출 방법을 이용해 얻어진 여러 개의 분류예측 결과 중 다수의 분류결과를 선택하는 앙상블 (arcing, bagging)기법을 적용하였다. 더불어, 본 연구에서는 클러스터링 방법을 제시하고, 이 방법이 기존의 융합기법, 앙상블기법과 비교한 결과, 분류예측면에서 정확도가 향상됨을 보였다.

• The Korean Journal of Emergency Medical Services
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• 제9권2호
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• pp.21-28
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• 2005

This study examines and analyzes EMTs works in hospital with 48 subjects working for hospitals at partial areas. It aims to provide basic materials for practice-centered learning to students at Dept. of Emergency Care and information of roles of EMTs. As a result of study, it was found that EMTs works included classification of severity of patients when they came to hosptial, supervision and move of serious case, move of patients and a member of cardiopulmonary resuscitation team as well as filling empty of medical staff and playing medical assistant under direct control of doctors and they played important roles in medical examination. These results showed that EMTs could extend their areas of service within hospital and they could have a positive influence on their seniors' employment.

• ETRI Journal
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• 제40권5호
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• pp.643-652
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• 2018

Dysarthria is a degenerative disorder of the central nervous system that affects the control of articulation and pitch; therefore, it affects the uniqueness of sound produced by the speaker. Hence, dysarthric speaker recognition is a challenging task. In this paper, a feature-extraction method based on deep belief networks is presented for the task of identifying a speaker suffering from dysarthria. The effectiveness of the proposed method is demonstrated and compared with well-known Mel-frequency cepstral coefficient features. For classification purposes, the use of a multi-layer perceptron neural network is proposed with two structures. Our evaluations using the universal access speech database produced promising results and outperformed other baseline methods. In addition, speaker identification under both text-dependent and text-independent conditions are explored. The highest accuracy achieved using the proposed system is 97.3%.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.629-632
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• 2008

Risk-based security impact evaluation may be affected by various factors according to numerous combinations of explosive devices, cutting devices, impact vehicles, and specific attack location to consider. Presently, in planning and design phases, designers are still often uncertain of their responsibility, lack of information and training of security. Therefore, designers are still failing to exploit the potential to reduce threats on site. In this study, the concept of security impact assessment is introduced in order to derive the performing design for safety in design phase. For this purpose, a framework for security impact assessment model using risk-based approach for bridge structures is suggested. The suggested model includes of information survey, classification of terror threats, and quantitative estimation of severity and occurrence.

• Osteoporosis and Sarcopenia
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• 제3권3호
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• pp.117-122
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• 2017

Sarcopenia is the degenerative loss of muscle mass and function with aging. Recently sarcopenia was recognized as a clinical disease by the International Classification of Disease, 10th revision, Clinical Modification. An imbalance between protein synthesis and degradation causes a gradual loss of muscle mass, resulting in a decline of muscle function as a progress of sarcopenia. Many mechanisms involved in the onset of sarcopenia include age-related factors as well as activity-, disease-, and nutrition-related factors. The stage of sarcopenia reflecting the severity of conditions assists clinical management of sarcopenia. It is important that systemic descriptions of the disease conditions include age, sex, and other environmental risk factors as well as levels of physical function. To develop a new therapeutic intervention needed is the detailed understanding of molecular and cellular mechanisms by which apoptosis, autophagy, atrophy, and hypertrophy occur in the muscle stem cells, myotubes, and/or neuromuscular junction. The new strategy to managing sarcopenia will be signal-modulating small molecules, natural compounds, repurposing of old drugs, and muscle-specific microRNAs.