격자볼츠만 방법을 이용한 도심지역 오염물질 확산에 대한 수치적 연구

정재화(Jae-Hwa Jung),변성준(Sung-Jun Byun),신명섭(Myung-Seob Shin),윤준용(Joon-Yong Yoon) 한국유체기계학회 2007 유체기계 연구개발 발표회 논문집 Vol.- No.-

The pollutant dispersion in a street canyon has been described in this study by using an two-dimensional lattice Boltzmann method coupled to the Smagorinsky sub-grid scale model. The pollutant source is divided ground-level source(Gl.S) and elevated source (ES). The obstacles were made a flat plate. The height of obstacle and distance of them were divided flow patterns as a isolated roughness flow, wake interference flow, skimming flow. The influence of the ratio between the height of the upstream and downstream canyon obstacles, as well as the gap distance between them was analyzed considering the situation of 'open country' and 'urban roughness'. The code for this research used large eddy simulation(LES) model by using lattice Boltzmann method(LBM).

합병증을 동반한 기관지 땅콩 흡인에서 체외막산소화 장치를 통한 치료 1예

정재화 ( Jae Hwa Jung ),설인숙 ( In Suk Sol ),윤서희 ( Seo Hee Yoon ),김민정 ( Min Jung Kim ),김윤희 ( Yoon Hee Kim ),신홍주 ( Hong Ju Shin ),박한기 ( Han Ki Park ),김경원 ( Kyung Won Kim ),손명현 ( Myung Hyun Sohn ),김규언 ( Kyu 대한천식알레르기학회(구 대한알레르기학회) 2016 Allergy Asthma & Respiratory Disease Vol.4 No.2

Foreign body aspiration commonly occurs, especially among children younger than 3 years of age. Most endobronchial foreign bodies may be easily removed by bronchoscopy and have a good prognosis. Despite advances in bronchoscopic procedures, difficulties in management of and complications from foreign body aspiration are still noted. We present a foreign body aspiration case with acute respiratory distress syndrome caused aspiration pneumonia, which was successfully treated by bronchoscopy under extracorporeal membrane oxygenation (ECMO). ECMO can be an effective and potentially life-saving method in complicated foreign body aspiration with uncompensated respiratory failure. (Allergy Asthma Respir Dis 2016;4:140-144)

1980-2019년 기간 동안 소아청소년 알레르기질환에서 항원 감작의 변화

정재화 ( Jae Hwa Jung ),김가은 ( Ga Eun Kim ),박미르 ( Mireu Park ),김수연 ( Soo Yeon Kim ),김민정 ( Min Jung Kim ),이용주 ( Yong Ju Lee ),김윤희 ( Yoon Hee Kim ),김경원 ( Kyung Won Kim ),손명현 ( Myung Hyun Sohn ) 대한천식알레르기학회 2021 Allergy Asthma & Respiratory Disease Vol.9 No.4

Purpose: Allergen sensitization is constantly changing, and understanding these changes can help manage and prevent allergic diseases. This research analyzed and compared the changes in allergen sensitization in children diagnosed with allergic diseases us-ing the skin test and the multiple allergen simultaneous test. Methods: We retrospectively analyzed the data on children who were diagnosed with allergic diseases and received immunother-apy at Yonsei Medical Center from 1980 to 1998 and they were screened for allergen sensitization at Severance Hospital from 2005 to 2019. Results: Between 1980 and 1998, and between 2005 and 2019, data on 3,205 (male, 70.3%; mean age, 7.2±2.9 years) and 15,318 children (male, 62.8%; mean age, 8.8±4.5 years) were analyzed. The sensitized allergens that appeared in the 1980-1998 included Dermatophagoides farinae (91.0%), Dermatophagoides pteronyssinus (76.3%), cockroach (13.5%), and Alternaria (11.5%), in order of frequency; further, the sensitized allergens that appeared in the 2005-2019 included D. farinae (45.0%), D. pteronyssinus (39.6%), cat dander (12.2%), and dog dander (9.1%), in order of frequency. D. farinae and D. pteronyssinus demonstrated the highest sensitization rates, although the rates decreased gradually. The sensitization to cat dander and dog dander showed a growing trend, and sensiti-zation to Humulus japonicus, Candida, and cockroach decreased after 2005. Conclusion: Over the past 40 years, the allergen sensitization in Korean children with allergic diseases has increased. These changes reflect lifestyle and environmental changes and influence allergic disease management approaches. Thus, changes in allergic sensi-tization should be monitored continuously. (Allergy Asthma Respir Dis 2021;9:208-215)

VRF 시스템의 가변패스 열교환기 기술

정재화(Jae Hwa Jung),김동휘(Dong Hwi Kim),장지영(Ji Young Jang),사용철(Yong Cheol Sa) 대한설비공학회 2018 대한설비공학회 학술발표대회논문집 Vol.2018 No.6

융합인재교육(STEAM)의 정책과 실행 방향에 대한 국내외 전문가들의 인식

정재화 ( Jaehwa Jung ),전재돈 ( Jaedon Jeon ),이효녕 ( Hyonyong Lee ) 경북대학교 과학교육연구소 2015 科學敎育硏究誌 Vol.39 No.3

이 연구의 목적은 융합인재교육(STEAM)이 가지는 가치, 필요성, 정당성을 탐색하고, 국내외 사례와 전문가들의 인식을 조사하여 우리나라 실정에 맞는 융합인재교육의 정책 및 실행 방향을 제시하고자 한다. 이 연구의 대상자는 2011학년도 전국의 초·중·고등학교에서 융합인재교육 연구학교의 실무를 담당한 교사 11명과 STEM/STEAM 교육과 관련된 국내 전문가 19명, 국외 전문가 12명이며, 이들이 소속된 기관의 프로그램 운영 사례를 논의의 대상으로 하였다. 우리나라의 융합인재교육 정책에서 고려되어야 할 점을 경험과 이해, 정책적 지원, 추진 방향의 측면에서 분석된 결과는 첫째, 경험과 이해의 측면에서 학교 현장에서 편리하게 적용하고 활동할 수 있는 프로그램 개발과 적용 방안이 제시되어야 하고, 이 교육 활동의 목표가 무엇이며 평가 체제와 환류에 대한 표준이 작성되어야 한다. 전문가들은 주제중심 학습이 가장 선호되는 학습이며, 창의적 사고력 개발과 실생활 적용능력을 위한 교육이 이루어져야 된다고 인식하고 있다. 둘째, 정책적 지원의 측면에서는 우수한 STEAM 교사 양성을 위한 다양한 프로그램과 정책적 유인책이 부족하다. 다양한 시각과 첨단 기술을 가미한 과학기술, 공학 및 예술과 인문사회를 아우를 수 있는 교재를 개발하여 보급하여야 한다. 이를 위해 교사들이 활동한 내용을 서로 나누고 자료를 쉽게 얻을 수 있는 STEAM 네트워크가 필요하다. 이 네트워크에는 기업체, 대학, 연구소 등의 관련 기관이 함께 참여할 수 있도록 정책적인 유도가 필요하다. 셋째, 추진방향의 측면에서는 현행 교육과정에서 STEAM교육이 자연스럽게 이루어 질 수 있는 정책 방안제시가 필요하다. 국내외 전문가들은 창의적 사고력을 기르는 교육과 함께 융합적 문제해결력을 기르는 교육 방향으로 나가는 것을 추천하고 있다. STEAM 교육과 관련된 정부의 부처 간의 협조에 의해서 이를 실천해 나갈 것을 요구하고 있다. The purposes of this study were to investigate the value, necessity and legitimacy of STEAM Education and to propose practical approaching methods for STEAM Education to be applicable in Korea through a variety of literature review, case studies and collecting suggestions from domestic and international educational experts. The research questions are as follows: (1) To investigate the perception, understanding and recognitions of domestic and foreign professionals in STEAM education. (2) To analyze policy implications for an improvement in STEAM. The following aspects of STEAM were found to be challenges in our current STEAM policy after analyzing multiple questionnaires with the professionals and case studies including their experiences, understanding, supports and directions of the policy from the governments. The results indicate that (1) there was a lack of precise and conceptual understanding of STEAM in respect to experience. Training sessions for teachers in this field to help transform their perception is necessary. Development of practical programs with an easy access is also required. It is important to get the aims of related educational activities recognized by the professionals and established standards for an evaluation. The experts perceived that a theme-based learning is the most preferred and effective approaching method and the programs that develop creative thinking and learning applicable to practice are required to promote. (2) The results indicate that there was a lack of programs and inducements for supporting outstanding STEAM educators. It is shown that making an appropriate environment for STEAM education takes the first priority before training numbers of teachers unilaterally, thus securing enough budget seems critical. The professionals also emphasize on developing specialized teaching materials that include diverse inter-related subjects such as science technology, engineering, arts and humanities and social science with diverse viewpoints and advanced technology. This work requires a STEAM network for teachers to link up and share their materials, documents and experiences. It is necessary to get corporations, universities, and research centers participated in the network. (3) With respect to direction, it is necessary to propose policy that makes STEAM education ordinary and more practical in the present education system. The professionals have recommended training sessions that help develop creative thinking and amalgamative problem-solving techniques. They require reducing the workload of teachers and changing teachers’ perspectives towards STEAM. They further urge a tight cooperation between departments of the government related with STEAM.

청소년의 구강보건행태가 치주조직 상태에 미치는 영향

정재화 ( Jae Hwa Jung ),김건엽 ( Keon Yeop Kim ),정성화 ( Seong Hwa Jeong ),김기수 ( Ki Su Kim ),이유미 ( Yu Mi Lee ) 한국치위생학회(구 한국치위생교육학회) 2014 한국치위생학회지 Vol.14 No.2

Objectives : This study aims to improve health and the quality of life of teenagers by identifyingan association between the periodontal status and oral health behaviors of Korean teenagers using2010 Korean National Oral Health Survey data. Methods : Subjects were teenagers aged from 12 to 15 in Korean National Oral Health Survey(KNOHS). The questionnaire consisted of periodontal status, general characteristics, periodontalrelated factors, and oral health related behaviors. Results : Gingival bleeding was found in 56.9% of teenagers because unhealthy periodontalstatus and tartars were found. Those who were 15 years old had unhealthier periodontal statusthan those who aged 12 years old. Those who lived in rural areas tended to have worse periodontalstatus than those who lived in the big cities. Access to dental floss, mouth rinsing solutionand regular dental checkup tended to make the healthier periodontal status. Smokers had theworse periodontal status than the nonsmokers. Conclusions : The oral health care in the teenagers aged from 12 to 15 is very importantbecause the permanent dentition is completed in this stage. It is necessary to lay emphasis onthe oral health improvement and dental caries prevention program to the teenagers.

Helicobacter pylori 제균 후 호전된 Menetrier 병

정재화 ( Jae Hwa Jung ),홍수진 ( Su Jin Hong ),이문성 ( Moon Sung Lee ) 대한소화기학회 2006 대한소화기학회지 Vol.48 No.1

구강암세포주에서의 Tamoxifen의 항암효과

정재화(Jae-Hwa Jung),윤필영(Pil-Young Yun),명훈(Hoon Myoung),신재일(Jae-Il Shin),이종호(Jong-Ho Lee),김명진(Myung-Jin Kim) 대한구강악안면외과학회 2003 대한구강악안면외과학회지 Vol.29 No.6

Tamoxifen is an selective estrogen receptor antagonist widely used in the management of patients with breast cancer for more than 30 years. It was thought to act primarily through occupying the estrogen receptor sites in ER positive breast cancer cells and directly on cancer cell proper. These inhibitory effects, which have been shown to be independent of the ER, highlight new mechanism of therapeutic action of tamoxifen. The purposes of this study were to identify ER in oral carcinoma cell lines and to evaluate ER independent cytotoxic effect of tamoxifen. KB(SCC), HSC-3(SCC) and A253(ACC) cell line were used and capacity of cell proliferation, apoptosis, in vitro invasion and gelatin zymography were tested. ER expression of each cell line were detected by RT-PCR and immunocytochemistry. Dose dependent inhibition of cell proliferation and inhibition of gelatinolytic activity were observed in all oral carcinoma cell lines and significant difference of apoptotic index were observed in A253 and KB. Tamoxifen inhibited in vitro invasion in all experimental groups. ER expression was detected in KB and A253. These data suggest that tamoxifen may play a role in management of oral carcinoma by independent cytotoxic effect and more advanced research must processed confirming ER-dependent cytotoxicity.

다중선 최근접 객체 질의

정재화(JaeHwa Chung),장홍준(HongJun Jang),정경호(KyungHo Jung),김성석(SungSuk Kim),길준민(JoonMin Gil),정순영(SoonYoung Jung) 한국정보과학회 2008 한국정보과학회 학술발표논문집 Vol.35 No.1

최근접 객체 질의(Nearest Neighbor Query)는 질의가 요청된 지점으로부터 가장 가까운 객체를 찾는 질의로 위치기반 서비스 분야에서 가장 널리 사용되고 있는 질의의 형태이다. 이를 기반으로 한 지역 최근접 객체 질의(Range Nearest Neighbor), 연속 최근접 객체 질의(Continuos Nearest Neighbor)등의 확장된 개념으로 다양한 최근접 객체 질의가 제안되어 왔다. 그러나 지금까지의 최근접 객체 질의를 기반으로 한 연구들은 점으로 표현된 질의를 기준으로 하여 최근접 객체를 찾는 기준점 최근접 객체(Point Nearest Neighbor) 질의를 기반으로 하고 있어, 점으로 표현이 불가능한 1차원 형태의 질의에 대하여 효과적인 최근접 객체를 검색하는 연구는 연구된 바 없다. 본 논문에서는 한 개 이상의 1차원 형태의 선분으로 이루어진 질의에 대하여 질의 주변의 객체 중 최근접 객체를 찾는 다중선 최근접 객체 질의(Polyline Nearest Neighbor)를 정의하고 효과적인 질의 처리 알고리즘을 제안하였다. 제안된 기법의 성능 분석을 위한 실험은 객체와 질의가 다양한 형태로 분포되어 있는 환경아래 진행되었으며, 실험 결과는 기대 값과 근접한 결과 값을 얻었다.

비공간 데이터 일치 조건을 포함한 최근접 객체 질의 처리

정재화(Jae-Hwa Chung),강상원(Sang-Won Kang),길준민(Joon-Min Gil),정순영(Soon-Young Jung) 한국정보기술학회 2009 Proceedings of KIIT Conference Vol.2009 No.-

위치기반 서비스 분야에서 대표적으로 사용되는 최근접 객체(NN) 질의가 거리조건 이외에 비공간 데이터 일치 조건을 부가적으로 포함하고 있는 경우 R-tree 색인을 기본으로 하는 NN 처리 알고리즘은 효율적으로 질의 결과를 생성할 수 없다. 본 논문은 이러한 비공간 데이터 일치 조건을 포함하는 최근접 객체(NN) 질의 처리 기법을 제안하였다. 각각 유일한 비공간 데이터에 개별키 역할의 ‘타입’을 할당하고 색인 탐색의 효율성을 높이기 위하여 타입를 고려한 거리인 STDIST와 이를 보조하는 변형된 색인 구조인 MTR-tree 색인을 제안하였다. 또한 정확한 성능 평가 결과 STDIST와 MTR-tree 사용한 NN 알고리즘이 보다 R-tree를 사용하는 INN기법보다 약 20%~25% 우수한 것을 입증하였다. In location-based service, if nearest neighbor query contains non-spatial predicates as well as spatial condition, then the conventional processing techniques may not produce results efficiently. This paper defines nearest neighbor query that contains non-spatial predicates. For the efficient query processing, this paper defines each unique non-spatial data value as unique key "type" and suggests a novel STDIST that elevates efficiency of index tree traversal. Also suggests variant of R-tree, MTR-tree that contains auxiliary data for STDIST. In performance evaluation, NSPNN algorithm which adopts STDIST and MTR-tree outperforms 20%~25% over INN algorithm with R-tree.