지역냉방 시스템용 초고효율 판형 열교환기 개발에 관한 연구

박재홍(Jae-Hong Park),임혁(Hyug-Lim),조성열(Sung-Youl Cho),강인성(In-Sung Kang),김정규(Jung-Kyu Kim),허인은(In-Eun Hur),고성규(Seong-Kyu Ko),곽승식(Sung-Sik Kwak),김종재(Jong-Jae Kim) 한국마린엔지니어링학회 2010 한국마린엔지니어링학회 학술대회 논문집 Vol.2010 No.10

Plate heat exchanger consists of thin, rectangular, pressed sheet metal plates that are sandwiched between full peripheral gaskets and clamped together in a frame. The frame has a fixed end-cover plate, fitted with the connecting ports, which is bolted together with a movable cover plate to hold the embossed plates in between; the top and bottom carrying bars allow proper alignment of the plate stacks. When compared with the well-established shell and tube heat exchangers, the plate heat exchanger shows a lot of advantages like high NTU values, compactness, low cost, multi duties and reduced fouling etc. Plate heat exchangers are often used to transfer heating or cooling water which is produced in the energy production( district heating or district cooling) facilities to residential areas and industrial parks. The district cooling systems of Middle East are the biggest market of plate heat exchanger, but the technical specifications for cooling system are different from the domestic one. To achieve its specifications, the new plate heat exchanger was developed, and its thermal performance results are introduced in this paper.

항공영상에서 상대 위치 추정 알고리듬의 실시간 구현

박재홍,김관석,김인철,박래홍,이상욱,Park, Jae-Hong,Kim, Gwan-Seok,Kim, In-Cheol,Park, Rae-Hong,Lee, Sang-Uk 대한전자공학회 2002 電子工學會論文誌-SP (Signal processing) Vol.39 No.3

본 논문에서는 TMS320C80 멀티미디어 MVP(multimedia video processor)를 이용한 항법 변수 추출의 구현 기법에 관하여 연구하였다. 특히, 항법 변수 추출 시스템의 실시간 구현에 중요한 역할을 하는 상대 위치 추정 알고리듬의 실시간 구현 방법에 관하여 고찰한다. 두 지점에서 취득된 영상을 이용하는 상대위치 추정 알고리듬을 근간으로 하여, 방대한 양의 계산량을 감축하면서 고정 소수점 프로세서에 적합한 고속 알고리듬을 개발한다. 그런 다음, MVP 내의 4개의 병렬 프로세서(PP; parallel processor)를 이용하여 병렬 처리할 수 있도록 알고리듬을 재구성한다. 그 결과, MVP를 이용한 항법 변수 추출 시스템은 초당 30프레임을 처리할 수 있음을 확인하여, 실시간 구현 조건을 만족시킴을 알 수 있었다. This paper deals with an implementation of the navigation parameter extraction technique using the TMS320C80 multimedia video processor (MVP). Especially, this Paper focuses on the relative position estimation algorithm which plays an important role in real-time operation of the overall system. Based on the relative position estimation algorithm using the images obtained at two locations, we develop a fast algorithm that can reduce large amount of computation time and fit into fixed-point processors. Then, the algorithm is reconfigured for parallel processing using the 4 parallel processors in the MVP. As a result, we shall demonstrate that the navigation parameter extraction system employing the MVP can operate at full-frame rate, satisfying real-time requirement of the overall system.

생활체육지도자의 직무관련요인이 이직의사에 미치는 영향

박재홍(Park Jae-Hong),신문형(Shin Moon-Hyoung) 한국체육과학회 2000 한국체육과학회지 Vol.9 No.1

The purpose of this study was to examine the factors that influence voluntary tunovers among leaders who are employed in Leisure and sports. The factors were found to he external, job-related, and personal. A survey was administered to 218 leaders of the following organizations that studied at Yong-in University, to success a third class leader in Leisure and sports with man 151 persons and female 67. A questionaire was designed to establish the causal factors of Yang-Jin Hawn(1992), Park-Se Hong(1994), Jun-Chan yol(1994), Lee-Ki Hyo(1995) in leisure and sports. The questionnaire had a high index in the Cronbach' a = .7108 ~ .8911 test. These surveys were cpmpleted using self-administration method. First, to analyze the data for the study, the frepuencies, t-test, one-way ANOVA was sued to analyze the collected data. The results of this study were as follews: First, the external factors associated with voluntary turnovers had not a stronger impact on the sex, education, prestige, salary on the decision. Second, the joh-related factors associated with voluntary turnovers has net friedship satisvaction and productivity.

신체형 장애에서의 Testosterone과 통각 역치의 상관관계

박재홍,김명정,박제민,김용기,한귀원,박성화,윤경일,정영인,김성곤,Park, Jae-Hong,Kim, Myung-Jung,Park, Je-Min,Kim, Yong-Ki,Han, Kwi-Won,Park, Seong-Hwa,Yun, Kyung-Il,Chung, Young-In,Kim, Sung-Gon 한국정신신체의학회 1998 정신신체의학 Vol.6 No.1

DSM-IV 진단 기준에 의하여 신체화 장애, 미분화 신체형 장애, 그리고 달리 분류되지 않은 신체형 장애여성 환자 13명과 정상 여성 20명을 대상으로 압통에 대한 통각 역치와 혈청 testosterone을 측정하여 다음과 같은 결과를 얻었다. 1) 가변 하중 압통 예민도 측정기 (Variable Weight Pressure Algometer)로 측정한 통각 역치는 환자군이 153.8${\pm}$39.5gm/$0.05mm^2$로서 대조군의 197.5${\pm}$66.7gm/$0.05mm^2$보다 유의하게 낮았다(p<0.05). 2) 혈청 testosterone치는 환자군에서는 0.175${\pm}$0.081ng/ml였고, 대조군에서는 0.174${\pm}$0.108ng/ml로서 양군간에 유의한 차이가 없었다. 3) Testosterone과 통각 역치와의 상관관계를 보면, 환자군에서는 혈청 testosterone치와 통각 역치 사이에 유의한 정적 상관관계가 있었으나(r=0.632, p<0.05, two tailed, Pearson's correlation test), 대조군에서는 유의하지 않았다(r=-0.405). 이상의 결과로 보아 신체화 장애 환자와 정상인 사이에 통각 예민도 조절 기전이 서로 다를 수 있다고 사료 된다. Thirteen female patients of somatization disorder, undifferentiated somatoform disorder and somatoform disorder, NOS, diagnosed by DSM-IV were studied for their pain threshold and serum testosterone and the results were compared with the respective data of 20 control females. The results are as follows : 1) The pain threshold as measured by Variable Weight Pressure Algometer was significantly lower in the patient group(153.8${\pm}$39.5 gm/$0.05mm^2$) as compared to the control group(197.5${\pm}$66.7 gm/$0.05mm^2$)(p<0.05). 2) There was no significant difference of serum testosterone between the patient(0.175${\pm}$0.081 ng/ml) and the control(0.174${\pm}$0.108 ng/ml) groups. 3) A significant positive correlation was noted between the pain threshold and serum testosterone in the patient group(r=0.632, p<0.05, two tailed, Pearson's correlation test), but not in the normal control group(r= -0.405). From these results, it was suggested that the role of testosterone in endogenous pain control system might be more important in somatoform disorders than normals.

CARIES-RELATED MICROBIOLOGICAL SCREENING IN CHILDREN UNDER THREE YEARS OF AGE

박재홍,이긍호,Park, Jae-Hong,Lee, Keung-Ho Korean Academy of Pediatric Dentistry 2003 大韓小兒齒科學會誌 Vol.30 No.4

3세 이하의 어린이에서 구강 내 미생물과 타액완충능이 치아우식증과의 관련성을 알아보았다. 87명의 어린이를 실험대상으로 하여 치태와 자극성타액을 각각 면봉과 면구를 이용하여 채취하였다. 0.94%의 lactic acid를 타액 표본에 첨가하기 전과 후의 pH를 각각 측정하였고 타액표본을 순차적으로 희석하여 선택배지와 비선택배지에 접종하였다. Mutans streptococci (MS), lactobacilli (LB), total viable count (TVC)의 집락수와 타액의 pH와 완충능을 어린이의 치아우식과 비교하여 다음과 같은 결과를 얻었다. 1. 자극성타액과 치태 모두에서 MS와 LB가 치아우식증과 높은 통계학적 유의성을 보였다. 2. 치아우식의 발생을 예측할 수 있는 미생물의 집락수는 다음과 같았다. 1) 자극성 타액 1 ml당 MS 집락수가 $10^5$ 이상 2) 치태 1 ml당 MS 집락수가 $2{\times}10^5$ 이상 3) 자극성타액 1 ml당 LB 집락수가 $10^3$ 이상 4) 치태 1 ml당 LB 집락수가 $10^3$ 이상 3. 타액의 pH와 완충능은 유아기우식증과 관련이 없었다. 4. MS 검사는 LB 검사 보다 높은 예측치 (predictive value)와 교차비 (odds ratio)를 보였다. 5. MS 집락수는 어린이에 있어서 치아우식 발생을 예측할 수 있는 가장 믿을만한 미생물학적 검사로 일반적인 세균배양법을 이용하거나 상품화된 검사기구를 이용하여 쉽게 임상에 적용할 수 있다. To evaluate microbial data and salivary measurements from clinically compatible, culture-based screening procedures employed with children younger than 36 months old. Plaque and stimulated saliva specimens were collected from 87 children. The pH of each saliva sample was measured before and after 0.94% lactic acid was added. Specimens were diluted and plated on selective media and non-selective media. Data collected were counts of mutans streptococci (MS) and lactobacilli (LB). In addition, total viable counts (TVC) of specimens, salivary pH and buffering capacity were also assessed. Each variable was compared to caries status of subjects. According to this study, the results were as followed: 1. Highly significant correlation with caries rates were found for counts of MS and LB. 2. The specific counts/ml saliva or plaque above which caries is predicted, or below which caries is not predicted were as follows: 1) Saliva MS; $10^5$ 2) Plaque MS; $2{\times}10^5$ 3) Saliva LB; $10^3$ 4) Plaque LB; $10^3$. 3. Salivary pH and buffering capacity versus caries status were not significant. 4. Microbial screening methods based on mutans streptococci had higher predictive values and odds ratios than methods for lactobacilli. 5. MS counts were clearly the best indicators of caries status in young children. This measurement can easily be obtained in a dental clinical setting both by conventional culture techniques, or commercial kits for MS recovery.

연재 : 축산과학원 - 양계 연구 동향 -닭의 스트레스 반응과 호르몬

박재홍,Park, Jae-Hong 대한양계협회 2010 월간 양계 Vol.42 No.8

도로표지 결로방지 예방기술에 관한 제언

박재홍,윤덕근,성정곤,강원의,Park, Jae-Hong,Yun, Duk-Geun,Sung, Jung-Gon,Kang, Weon-Eui 대한교통학회 2011 교통 기술과 정책 Vol.8 No.5

에폭시 분체도료의 경화제 종류에 따른 물성에 관한 연구

박재홍,신영조 ( Jae Hong Park,Young Jo Shin ) 한국공업화학회 1998 공업화학 Vol.9 No.1

에폭시계 분체도료에 사용되고 있는 경화제로는 치환 dicyandiamide(Sub-DICY), 촉진 dicyandiamide(Acc-DICY), trimellitic anhydride(TMA), pyromellitic dianhydride(PMDA), phenolic curing agent(Ph.C.A.)등이 사용되고 있다. 본 연구는 상기 5가지 의 에폭시 경화제를 사용해서 제조한 에폭시 분체도료를 적합한 경화조건에서 완전히 경화시킨뒤 여러 가지 실험기기 및 분석기기를 이용해서 경화된 도막의 Tg, 인장강도, 파단신율, 경도, 내마모성등의 기계적 물성을 측정하였다. 그리고 흡수율, 내산성, 내 알카리성등의 화학적물성, 전기적특성, 방식성등을 측정함으로써 경화제의 종류에 따른 에폭시 도막의 화학구조가 도막의 물성에 미치는 영향을 비교하였다 그결과 Phenolic curing agent는 toughness가 우수하지만 온도에 따른 색상 변화가 크고 산무수물 경화제는 전기절연성과 온도에 따른 색상안정성이 우수하지만 toughness와 부착성이 부족하고 DICY계는 흡수율과 온도에 따른 색상변화가 큰 특성을 나타내었다. Substituted dicyandiamide(Sub-DICY), Accelerated dicyandiamide(Acc-DICY), Trimellitic anhydride(TMA), Pyromellitic dianhydride (PMDA) and Phenolic curing agent(Ph.C.A) are mainly used for epoxy powder coating curing agent. Various characteristics of epoxy films fully cured by optimum condition such as mechanical properties like T_g, tensile strength, elongation at break, hardness, abrasion resistance and chemical properties like water absorption, acid resistance, alkali resistance and electrical properties, corrosion resistance are determined by various measuring devices and analysys devices. In conclusion, phenolic curing agent was shown excellent thoughness but severe color change as temperature increased. Acid anhydride has excellent insulation properties and color stability at elevated temperature but lower thoughness and adhesion to substrate. DICY curing agent was shown high water absorption and severe color change as temperature increased.

만성 누소관염의 임상양상과 치료

박재홍,노주헌.Jae Hong Park. MD. Joo Heon Roh. MD 대한안과학회 2013 대한안과학회지 Vol.54 No.10

Purpose: To report on the clinical manifestations, species and treatments of patients with chronic canaliculitis. Methods: From August 2003 to February 2012, 77 eyes of 77 patients who were diagnosed with chronic canaliculitis at our hospital were retrospectively analyzed. Results: The mean period from the onset of symptoms to diagnosis was 4.7 months. The most common systemic disease associated with chronic canaliculitis was diabetes (18 eyes, 23%), and 13 eyes (17%) were related to punctual plug insertion. Main symptoms consisted of epiphora with discharge and pouting punctum. In the culture results of 55 eyes, streptococci, staphylococci, and actinomyces among other bacteria were identified. Seventy-two eyes (94%) were cured with one-snip punctoplasty with curettage. Conclusions: Chronic canaliculitis is rare, and the clinical aspect can be obscured by chronic conjunctivitis, thus the diagnosis is often delayed. In patients who have systemic diseases such as diabetes or past history of punctual plug insertion, chronic canaliculitis should be differentiated by observing the punctum more closely. If the diagnosis is accurate at the time, chronic canaliculitis could be easily cured by a relatively simple procedure such as one-snip punctoplasty with curettage.

만성 복통을 보이는 환자 어떤 순서로 접근을 해야 하나요?

박재홍,Park, Jae-Hong 대한소아소화기영양학회 2011 Pediatric gastroenterology, hepatology & nutrition Vol.14 No.1

Chronic abdominal pain (CAP) is a common complaint encountered in pediatric clinics and a great concern for patients and their caretakers as well as health care professionals. A constant challenge is detecting individuals with organic diseases or psychosomatic disorders from the majority of patients who have a functional disorder including functional dyspepsia, irritable bowel syndrome, functional abdominal pain, and abdominal migraine. Beginning with a detailed history and physical examination, physicians must determine a differential diagnosis of CAP by applying the symptom-based Rome III criteria to positively identify a functional disorder. These findings should then be further analyzed based on diagnostic clues and red flags that indicate the presence of specific organic diseases and/or the need for further testing. Once a functional diagnosis has been made or an organic disease is suspected, physicians can initiate an empiric therapeutic trial. Since psychological distress accompanies both organic and non-organic abdominal pain in children, a cooperative diagnostic approach involving pediatricians and psychiatrists is recommended.