물액적에 의한 미연소면의 냉각에 관한 실험적 연구

방창훈,김정수,예용택 한국화재소방학회 2000 한국화재소방학회논문지 Vol.14 No.3

본 연구의 목적은 물액적에 의한 미연소면의 냉각 특성을 연구하는 것이다. 고온고체로는 황동, 탄소강, 동을 사용하였으며 온도범위는 70℃~116℃이다. 액적의 직경은 2.4 mm~3.0 mm로 하였다. CCD카메라를 이용하여 액적의 증발과정을 기록하였으며, 증발시간은 비디오에 기록된 프레임을 분석하여 구하였다. 열전도도가 가장 큰 동의 경우 액적이 떨어진 직후조금 냉각되었다가 일정 온도를 유지하지만 열전도도가 낮은 탄소강의 경우는 증발시간 동안 약 1℃ 정도의 온도 기울기가 나타났다. 고체 표면에서의 액적증발시 무차원 액적체적은 가열체의 재질에 상관없이 무차원 증발시간이 증가할수록 선형적으로 감소한다. The objective of the present work is to examine the cooling characteristics of water droplet on the unburned surface. The hot solid surface material used brass, carbon steel and copper at temperature ranging from 70 to 116℃. the droplet size is from 2.4 mm to 3.0 mm. The CCD camera was used to record the evaporation histories of the droplets. and the evaporation time of the droplet on the hot solid surface could be determined by using frame-by-frame analysis of the video records. It is found that during the droplet evaporation process for copper the temperature remains nearly constant, whereas for carbon steeel the temperature continuously decreases about 1℃. During the droplet evaporation process on the hot solid surface, regardless of solid materials, nondimensional droplet volume decreases nondimensional evaporation time increases.

표면 거칠기에 따른 액적의 증발 냉각

방창훈,권진순,예용택 한국안전학회 2003 한국안전학회지 Vol.18 No.3

The objective of the present work is to examine evaporation cooling of droplet due to surface roughness on a heated surface. The surface temperatures varied from 80~160℃ on aluminum alloy (AL 2024) and surface roughness was 0.18μm, 1.36μm. The results are as follows; Regardless of surface roughness, as droplet diameter is bigger, the in-depth temperature of solid decreases and evaporation time increases. In the case of same initial temperature on the heated surface, as droplet diameter is smaller and small surface roughness is bigger, evaporation time decreases and time averaged heat flux increases.

정신분열증과 주요정동장애의 증상 비교

방승규,김용찬 大韓神經精神醫學會 1982 신경정신의학 Vol.21 No.2

This study is to investigate the difference in the symptom manifestations of schizophrenia and major affective disorder. The subjects consisted of 726 schizophrenics and 108 cases with major affective disorder who had been admitted to the psychiatric ward of Yoido St. Mary's hospital, Catholic Medical College from June. 1, 1975 to Dec. 31, 1978. The results were as follows; 1. The symptoms occurring only in schizophrenic patients were waxy flexibility, echolalia, echopraxia, neologism, visual hallucination and other hallucination. 2. The symptoms which occurred with a statistically significant rate in schizophrenic patients were stereotypic activity, praecox feeling, blunting or flattening of affect, poor insight, loosening of association, magical thinking, autism, idea of reference, bizarre delusion, persecutory delusion, auditory hallucination and characteristic hallucination. The symptoms which occurred with a statistically significant rate in the patients with major affective disorder were increased psychomotor activity, mutism, euphoria or elation flight of idea, retardation of thought and other delusion. 3. Flight of idea and euphoria or elation showed statistically significant relationship to major affective disorder.

유독 중금속 오염물질 처리를 위한 미생물균주의 최근 이용 및 개발

방상원,최영길,한명수 한국환경생물학회 2001 환경생물 : 환경생물학회지 Vol.19 No.2

There are several ways to remove and treat toxic heavy metals in the environment: chemical, physical and biological ways. The biological treatment utilizes the natural reactions of microorganisms living in the environments. These reactions include biosorption and bioaccumulation, oxidation and reduction, methylation and demethylation, metal-organic complexation and insoluble complex formation. The biological reactions provide a crucial key technology in the remediation of heavy metal-contaminated soils and waters. According to recent reports, various kinds of heavy metal species were removed by microorganisms and the new approaches and removal conditions to remediate the metals were also tried and reported elsewhere. This was mostly carried out by microorganisms such as fungi, bacteria and alga. In addition, a recent development of molecular biology shed light on the enhancing the microorganism's natural remediation capability as well as improving the current biological treatment.

폐광지역 토양과 농작물 중의 중금속 오염도 조사

방은옥,정용준,조영채 忠南大學校 環境問題硏究所 2002 環境硏究 Vol.20 No.-

This study was conducted to investigate the concentration of the heavy metals among the soils and crops, and the difference compared with the unpolluted area from the radius distance from the ruined mine. Gubong Mind in Cheongyang-Gun, Chungnam-Do was selected as the ruined mine, which the Taechi-Myon district was selected ad the unpolluted control area. Pepper, welch onion, cabbage, radish and their soils were collected at the mine and unpolluted area, respectively. The concentration of heavy metals(Pb, Cd, Cu, Zn and As) were measured by ICP. In the soil sample, the average concentrations of all the heavy metals were significantly increased in the min area compared with those of the unpolluted area and significantly differed from the radius distance from ruined mine. In the crop sample, the average concentration of Pb, Zn and As metals were significantly increased in the mine area compared with those of the unpolluted area and all the heavy metals were significantly differed from the radius distance from ruined mine. There was a significant negative correlation among the soils from the radius distance from ruined mine and among the crops in the concentrations of all the heavy metals. There was a significant positive correlation between soils and crops in concentration of Pb, Cd, Zn and As metals. The results indicate the concentrations of heavy metals among the soils and crops at the ruined mine were saturated more than the unpolluted and the soil metals had spread to the crops. Consequently, we cannot leave the matter unsettled and its utilization must be studied to lower the contamination degree.

복사열에 노출된 작업복의 열적특성에 관한 실험적 연구

방창훈,이진호,예용택 한국산업안전학회 2002 한국안전학회지 Vol.17 No.3

The purpose of this study was to present the thermal characteristics of the working uniform exposed to the radiation heat. The effect of exposure time and exposure distance on the changes and the relationship between physical properties were investigated experimentally. Regardless of the kind of working uniform, the surface temperature of the working uniform with exposed time sharply increases as exposed distance is more close and the reaching tie of steady state is shorter. The surface temperature of working uniform exponentially decreases as exposed distance become more distant. For the safety of the working man, it is necessary that he work far away at a fixed standard distance from the radiant heat source.

화성(華城) 방문객 프로파일에 의한 마케팅 리서치

방용원,노영희 경기대학교 화성학연구소 2004 화성학연구 Vol.- No.1

This study is to propose some promotional strategies based on marketing research of the visitors' profiles in Hwaseong. Although Hwaseoung is designated as one of the UNESCO's cultural heritages, more than 70 percent of the visitors visit there for sightseeing, promenade, and family outing. Therefore, for a promotional strategy for Hwaseoung, marketers should recognize the destination not only as a cultural heritage but also as a neighboring park district for Suwon City.

視覺制禦時 時間豫測의 最終 피드백效果

方美玉,林容圭 漢陽大學校 體育科學硏究所 1986 體育科學 Vol.6 No.6

The purpose of this present study was to investigate the effects of terminal feedback learning on timing anticipation in visual control, subjects(each 60 boy and girl's middle school students randomly selected) were learned with cramming of three level KR (Know ledge of Results) and tested their ability of timing anticipation without vision by a total 720 trials. The results are as follows: 1. After learning, MK100, MK50 groups showed a improved ability of timing anticipation as p<0.05, but MKO; FK100, FK50, FK50 groups showed insignificant improvement. 2. After learning, MK100 group is superior to MK50 as DMO. 538 (p<0.001) , MK50 group to MKO as DM0.657 (p<0.001), FK100 group to. FK50 as DM0.283) p<0.001), FK50 to FK0 as DM0.060 (p<0.001) but, in the case of MK 100 VS MK0 group, there is no significant difference. 3. In comprison between Boy and Girl' group, Boy'group seperior to Girl'as DM 0.172(p<0.05).

실시간 시스템에서 균등 분배된 여유시간을 활용한 동적 전압 조절

방철원,김용석 강원대학교 정보통신연구소 2004 정보통신논문지 Vol.8 No.-

Recently, mobile systems are used widely in various applications. Due to limited power supply, reducing power consumption becomes a matter of primary concern. As an approach to reduce power consumption, voltage can be scaled down, according to the execution tine and deadline of tasks. By lowering the supplying voltage to 1/N, power consumption can be reduced to I/N². DPM-S is a well known method for dynamic voltage scaling which is based on average execution time. However, the actual execution time of a task can vary from the average execution time. Due to the misprediction of the actual execution time, DPM-S can be worse than DPM-P In this paper, we presented EDSS where static slack is evenly divided among tasks. Our simulation result shows that EDSS can achieve up to 13% energy saving than DPM-S and DPM-P.

복사가열조건에서 표면 거칠기에 따른 액적의 증발 냉각

방창훈,권진순,예용택 한국안전학회 2004 한국안전학회지 Vol.19 No.3

The objective of the present work is to examine evaporation cooling of droplet due to surface roughness under radiative heat input condition. The surface temperatures varied from 80~160℃ on aluminum alloy (AL 2024) and surface roughness was 0.18μm, 1.36μm. The results are as follows; Regardless of surface roughness under radiative heat input condition, as droplet diameter is larger, the in-depth temperature of solid decreases and evaporation time increases. In the case of 0.18μm and 1.36μm of surface roughness, the larger the surface roughness is, the less the evaporation time is and the larger the temperature within the solid is. In the case of Ra = 0.18μm, evaporation time and time averaged heat flux for radiative heat input case is shorter than for the conductive case.