인공신경망을 이용한 태양광열 시스템의 열 및 전기 성능예측 모델 개발

오진환,배상무,남유진 대한설비공학회 2022 설비공학 논문집 Vol.34 No.4

Recently, Zero Energy Building (ZEB) that reduces the energy consumption and energy demand is becoming major issue. To realize ZEB, high energy efficiency renewable energy systems are actively applied in the building. Among the renewable energy systems, the photovoltaic-thermal (PVT) systems can respond heat and electricity demands of the buildings with one facility. Although, it is necessary to accurately predict the performance of the PVT system, most studies are conducted at the mock-up test level, through energy simulation and laboratory-scale experiment. In this study, the real-scale experiment plant that comprises the PVT module, heat storage tank, and actual building was constructed to collect the database of the PVT system under actual conditions. Moreover, based on the real-scale experimental data, the performance prediction model was constructed using artificial neural network (ANN). To verify the accuracy of the performance prediction model based on ANN, the coefficient of variation root mean square error (Cv(RMSE)) proposed by ASHRAE Guideline 14 was used. The Cv(RMSE) for the predicted result by ANN was calculated as 10% of the thermal efficiency, and 16% of the electrical production. Through the Cv(RMSE) result, it was confirmed that the performance prediction model based on ANN is reliable. 본 연구에서는 소규모 사업자 및 실무자 등이 시스템 성능을 설계단계에서 검토할 수 있는 기초자료로써 활용하기 위하여 인공신경망 기반 PVT 예측 모델을 구축하였다. 또한, 실증실험을 통하여 수집된 데이터와 인공신경망의 예측결과를 비교하여 구축된 인공신경망 모델을 검증하였다. 본 연구의 결과에 대한 요약은 다음과 같다. (1) 실증실험을 수행하여 인공신경망의 입․출력 데이터를 수집하였으며, 피어슨 상관계수 분석을 통하여 결정계수가 0.2 미만인 변수는 제거하였다. 선별된 입력변수는 정규화 과정을 거쳐 인공신경망 모델에 적용하였다. (2) 입․출력 데이터에 대한 피어슨 상관계수 결과를 토대로 결정계수(r2)를 산출하여 PVT 열효율은 PVT 유량 및 일사량, PVT 발전량의 경우 외기온도, 일사량이 가장 큰 영향을 미치는 것을 확인하였다. (3) 실증실험을 통하여 측정된 데이터와 인공신경망 모델의 예측결과의 해석 결과 간 Cv(RMSE)는 PVT 열효율 10.44%, PVT 전력생산량 16.34%로 계산되었다. 따라서, 본 연구에서 개발된 인공신경망 기반 PVT 성능예측 모델은 ASHRAE Guideline 14-2014에서 제안하는 30% 범위에 수용하여 신뢰성이 있음을 확인하였다. (4) 본 연구에서 개발된 인공신경망 기반 PVT의 성능 예측 모델은 설계 변수가 다수 필요한 기존의 에너지 시뮬레이션보다 모델 구축 및 해석 시간을 단축할 수 있을 것으로 사료된다. 본 연구에서는 하절기의 PVT 실험 데이터에 기반하여 성능예측 모델을 구축하였으므로 PVT의 연간 성능을 정확히 예측하기에는 한계점이 있다. 향후, 동절기 장기간 실험 데이터를 수집하여 다양한 다수의 데이터를 확보 및 적용하여 오버피팅(Overfitting)을 억제하여 개발된 PVT 시스템 성능예측모델의 정확도를 향상시킬 예정이다.

國家開發과『매스 · 메디아』의 課題

吳鎭煥 관훈클럽 1966 관훈저널 Vol.- No.10

결핵성 중이염 : 3예 보고

오진환 대한영상의학회 1998 대한영상의학회지 Vol.39 No.1

저자들은 결핵성 중이염 3예의 영상소견을 보고하고자 한다. 모든 예가 병리학적으로 진단되었고 CT는 모든 예에서 MRI는 2예에서 시행되었다. 전예에서 외이도에 연부조직 음영이 있었고 2예에서 유양골 골소주 및 Tegmen근처의 내측 굴피질의 파괴가 보였다. 안면신경마비를 호소하였던 2예에서 안면신경관 미란이 있었다. MRI상 풍부한 육아조직이 중이 및 유돌골 기세포에서 관찰되었다. 내이도 내의 청신경 및 안면신경, 그리고 와우관 조영증강이 1예에서 보였고 다른 1예에서 전정 및 외측 반고리관의 조영증강이 있었다. 만성중이염이 환자의 방사선학적 검사에서 골수주 및 Tegmen의 파괴, 안면신경 침범, 풍부한 육아조직, 그리고 내이의 조영증강이 있으면 결핵성 중이염을 감별진단에 포함시켜야 할것으로 사료된다. We report the imaging features of three cases of tuberculous otitis media. All three patients under went temporal bone CT scanning, and in two, additional MRI scanning was performed. The three cases showed soft tissue density in the external auditory canal, and in two, destruction of the trabeculation and internal cortex of the mastoid bone was noted. In two patients with facial palsy, erosion of the facial canal was seen. On MRI, abundant granulomatous tissue was noted in the middle ear cavity and mastoid air cells. In one case, abnormal enhancement of the cochlea, and of the facial and eighth cranial nerve in the internal acoustic canal was seen. Another case showed enhancement of the vestibule and lateral semicircular canal. If radiologic evaluation of chronic otitis media reveals destruction of the tegmen and trabeculation of the mastoid bone, together with abundant granulation tissue and enhancement of the internal ear, tuberculous otitis media may be included in the differential diagnosis.

로봇 테크놀로지 기반의 노인간호 활용전망

오진환 한국노인간호학회 2018 노인간호학회지 Vol.S No.-

Purpose: The purpose of this study was to investigate the possibility of using intelligent robot based nursing practice as discussed in previous research and also, to propose directions for robot care for elders. Methods: For this study 28 previous researches using robots in health care field were reviewed and related research trends introduced. Results: Robot applications in the healthcare field were mainly for rehabilitation, surgery, interaction, and nursing assistance through robotics. Especially types of robot include pet type robots, humanoid robots, surgical robots, rehabilitation robots, robot suit and entertainment robots with monitors. The research participants were patients with dementia and institutionalized elderly people. It was found that a human-robot interaction was effective from physical, mental, emotional and social aspects. Conclusion: Robots can be used for various purposes such as nursing assistance, patient health promotion and education. It is necessary to reduce the human burden of care work using robots and to introduce robot care programs which can meet the needs of elders. Therefore, korean nurses should make efforts to change their practice to new geriatric nursing through repeated research based on the scientific data.

만성 관절염 환자의 가족지지, 자기효능감 및 치료지시 이행과의 관계

오진환 한국간호과학회 2004 한국간호과학회 학술대회 Vol.2004 No.5

과학기술발전과 언론의 과학보도

오진환,O, Jin-Hwan 한국과학기술단체총연합회 1978 과학과 기술 Vol.11 No.7

Where is Uzbekistan’s trade and where should it be directed? Gravity analyses for being doubly landlocked

오진환,Bekzod Yuldashev,Soo Hyun Moon 한국외국어대학교 국제지역연구센터 2018 International Area Studies Review Vol.21 No.1

This study applies the gravity model to describe Uzbekistan’s trade pattern, based on which several policy implications are made. We find that Uzbekistan’s estimated trade flows with Ukraine, Russia, China, and South Korea are much more than the actual flows, while the country’s economic contacts with its neighboring countries (Tajikistan, Kazakhstan, Kyrgyzstan, and Azerbaijan) are far less than expected. This suggests that Uzbekistan should strive to increase trade with neighboring countries, through taking part in a free trade agreement between countries of Central Asia, or strategically using neighboring countries bordering the Caspian Sea and Arabian Sea.

South Korea’s regional disparities and the 2018 Winter Olympics for regional development: Big Push revisited

오진환 한국외국어대학교 국제지역연구센터 2017 International Area Studies Review Vol.20 No.2

Using the Theil decomposition method, this study analyzes regional inequality in South Korea and finds the country’s regional income disparities have been growing over the past two decades. Further group-specific analyses using the between and within group decompositions provide the following findings: (1) the inequality between Honam and non-Honam has been declining, repudiating the claim that Honam has been discriminated against by other regions; and (2) discrepancies between Gangwon and other regions have been growing, which is more serious than the Honam case and which is a priority of this research. In line with this, Gangwon Province the 2018 Winter Olympics is expected to contribute to narrowing this gap. Lessons from the Japanese experiences with the 1998 Winter Olympics will be discussed.

복부수상후 소장파열의 전산화 단층촬영 소견

오진환 대한영상의학회 1995 대한영상의학회지 Vol.32 No.5

Purpose: The accuracy of CT in the detection of injuries of the solid visceral organs is well established, butthe value of CT in diagnosing small bowel rupture after abdominal trauma is controversal. This study was conductedto ascertain CT finding of small bowel rupture result from abdominal trauma. Materials and Methods: Aretrospective analysis of preoperative abdominal CT findings in 40 patients was performed. Small bowel rupture wasconfirmed by surgery. Precontrast and postcontrast enhanced CT images were obtained in all patients. Results:Diagnostic findings of small bowel rupture including pneumoperitoneum or retroperitoneal air, discontinuity of thebowel wall and extravasation of oral contrast materials were observed in 33 cases(83%). Intraperitoneal orretroperitoneal free air was seen in 31 cases(78%) and intraperitoneal or retroperitoneal free fluid collectionwas seen in 38 patients(95%). Small bowel wall was thickened in 31 cases(78%), bowel wall was enhanced in 12cases(30%) and bowel wall discontinuity and extravasation of oral contrast material was seen in 5 cases,respectively. Conclusion: The CT scan is sensitive and effective modality for evaluation of small bowel ruptureafter abdominal trauma, because of high detectability of diagnostic and suggestive CT findings.

適法한 勞動爭議로 인하여 運轉實務에 從事하지 못한 경우 個人택시 免許 基本上의 運轉經歷 認定與否

吳振煥 법조협회 1994 法曹 Vol.43 No.12