• Title/Summary/Keyword: Fog

Search Result 722, Processing Time 0.029 seconds

A Study on the Micro-climate Characteristics of Haheo Village (하회마을의 미기수특성에 관한 연구)

  • 황정하;호야노아키라;도근영;스가와라마사노리;혼마히로부미;정명섭
    • Journal of the Korean housing association
    • /
    • v.11 no.3
    • /
    • pp.137-144
    • /
    • 2000
  • The purpose of this study is to examine the climate characteristics of Haheo in order to find ecological design of a traditional village and residence. In this study, the weather data during sixteen month from May 1998 to August 1999 was measured and analyzed. The results of this study were as follows; 1) In winter, the west wind was dominant at the 60% of rate during the day. The rate of west wind decreased to 30% at night, while the rate of south wind and south-east wind increased to 40%. 2) The relative humidity was higher than 90% at morning because of a fog in summer. 3) In summer, there were many days that the air temperature rose over $30^{\cire}C$ in the daytime, but the air temperature fell about $20^{\cire}C$ at night.

  • PDF

A Feasibility Study on the Economic Aspect of Sea Transportation System between Inchon and Youngjong Island (인천-영종 간 해상수송시스템 구축을 위한 경제적 타당성 분석)

  • Chun, Jae-Woo;Lee, Seung-Hee
    • Journal of Ocean Engineering and Technology
    • /
    • v.13 no.3B
    • /
    • pp.116-126
    • /
    • 1999
  • The purpose of this study is to analyze the economic aspect of sea transportation system between Inchon and Youngjong island in which Inchon international airport is being constructed. Total demand of sea transportation arising from in the airport and Yongyu Muwi leisure complex was estimated. To select optimum transportation route, environmental conditions in and around Inchon harbour and Youngjong island including the change of water depth by tide current, fog, rain, wind adn typhoon, ets., were investigated. The preliminary consideration on ships (size, velocity, transport capacity, price), routes, operational modes, terminals and berthing facilities were carried out. The transportation cost per passenger by sea transportation system was estimated to compare with that of land transportation system. It was found that sea transportation system proposed is competitive to the transportation system.

  • PDF

The Effects of Environmental Factors on Degradation and Hydrophobicity Recovery Characteristics in RTV Silicone Rubber (RTV 실리콘 고무의 열화 및 발수성 회복 특성에 미치는 환경인자의 영향)

  • Heo, Chang-Su;Yeon, Bok-Hui;Jo, Hyeon-Uk;Hwang, Myeong-Geun
    • The Transactions of the Korean Institute of Electrical Engineers C
    • /
    • v.48 no.6
    • /
    • pp.462-468
    • /
    • 1999
  • Room temperature vulcanizing (RTV) silicone rubber has been widely used to coat porcelain insulators to render water repellency to prevent formation of water film on the surface and thus to suppress the leakage current and consequently flashover. However, the electrical property and the hydrophobicity of RTV silicone rubber coating under outdoor condition may be influenced by many environmental factors. In this studyvarious treatments, such as salt-fog, salt water immerging and UV irradiation were applied to the samples to investigate the change of the electrical property and hydrophobicity. As a result the leakage current increased and contact angle decreased asthe degradation time is longer. But the degraded RTV silicone rubber has recovered its hydrophobicity during the drying time in ambient condition because LMW(Low Molecular Weight) silicone fluid diffused from the bulk to the surface.

  • PDF

Foodborne Pathogen Reduction을 위한 항균제의 새로운 Delivery System인 Aerosolization

  • O, Se-Uk;Gang, Dong-Hyeon
    • Bulletin of Food Technology
    • /
    • v.18 no.1
    • /
    • pp.91-98
    • /
    • 2005
  • Aims: As a preliminary experiment on new sanitizer delivery tools, the efficacy of aerosolizedsanitizer on foodborne pathogens was investigated in larger model chamber system.Methods: Peroxyacetic acid and hydrogen peroxide were aerosolized in a model system againstartificially inoculated target microorganisms on laboratory media. Cultures of 4 different foodborne pathogens were inoculated and affixed onto 3 different heights (bottom, wall, and ceiling), and 3different orientations (face-down, vertical, and face-down) inside a commercial semi-trailer cabinet(14.6 x 2.6 x 2.8 m). Sanitizer was aerosolized into 2 m droplet size fog and treated for 1 h atambient temperature.Results: Populations of Bacillus cereus, Listeria innocua, Staphylococcus aureus, and Salmonellatyphimurium were reduced by an average of 3.09, 7.69, 6.93 and 8.18 log units per plate, respectively.Interestingly, L. innocua, Staph. aureus, and Salm. typhimurium showed statistically not different (P$\leq$ 0.05) reduction patterns relative to height and orientation that were never expected in a sprayingsystemConclusion and significance: Aerosolized sanitizers diffuse like gaseous sanitizers, so it has greatpotential for use in commercial applications.

  • PDF

Clinical Application of F-18 FDG PET(PET/CT) in Malignancy of Unknown Origin (원발부위미상암에서 F-18 FDG PET (PET/CT)의 임상 이용)

  • Kim, Byung-Il
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.42 no.sup1
    • /
    • pp.162-165
    • /
    • 2008
  • Diagnosis of primary origin site in the management of malignancy of unknown origin (MUO) is the most important issue. According to the histopathologic subtype of primary lesion, specialized treatment can be given and survival gain is expected. F-18 FOG PET (PET/CT) has been estimated as useful in detection of primary lesion with high sensitivity and moderate specificity. F-18 FDG PET (PET/CT) study before conventional studies is also recommended because it has high diagnostic performance compared to conventional studies. Although there has few data, F-18 FDG PET (PET/CT) is expected to be useful in diagnosis of recurrence, restaging, evaluation of treatment effect, considering that PET (PET/CT) has been reported as useful in other malignancies.

Clinical Application of $^{18}F-FDG$ PET in Brain Tumors (뇌종양에서의 $^{18}F-FDG$ PET의 임상 이용)

  • Hong, Il-Ki;Kim, Jae-Seung
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.42 no.sup1
    • /
    • pp.1-5
    • /
    • 2008
  • Primary brain tumor accounts for 1.4% of entire cancer. For males between the ages of 15 and 34 years, central nervous system tumors account for the leading cause of cancer death. $^{18}F-FDG$ PET has been reported that it can provide important diagnostic information relating to tumor grading and differentiation from non- tumorous condition. In addition, the degree of FDG metabolism carries prognostic significance. By mapping the metabolic pattern of heterogeneous tumors, $^{18}F-FDG$ PET can aid in targeting for stereotactic biopsy by selecting the subregions within the tumor that are most hypermetabolic and potentially have the highest grade. According to clinical research data, FOG PET is expected to be a helpful diagnostic tool in the management of brain tumors.

A Study on the Bow Collapse of High-Speed Passenger Craft in Collision with Bridge Pier (고속 여객선의 교각 충돌에 대한 연구)

  • 신영식;박명규
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.5 no.1
    • /
    • pp.1-8
    • /
    • 1999
  • During the last 10 years, the various type of high speed craft have been greatly developed, and since around of 1990 the large size of high speed passenger and/or cargo vessels are also introduced and took into the service in the various routes over the world. In a marine traffic way some bridge need to build across a rivers, cannals or a waterways. This one will be an obstruction and potential risk of collision in the way of high speed craft. Accordingly some of collision accident have been reported, which were caused by a lost control, wind and hydrodynamic forces, fog or human errors. In this paper a high speed craft having 40 m length is assumed to be collided with a circular type of bridge piers at right angle. The mode of deformation, penetration depth of collapse, impact forces, reduction of speed, loss of kinetic energy, and influence of scantlings, etc. have been calculated in each speed with a time variation to find a maximum values within a limit, and are graphically presented.

  • PDF

A Satellite Attitude Compensation Scheme Using Sun Sensor (태양센서를 이용한 인공위성의 자세보정기법)

  • Rhee, Sung-Ho;Lim, You-Chol;Kwak, Hwy-Kuen;Lyou, Joon
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.13 no.7
    • /
    • pp.703-710
    • /
    • 2007
  • This paper presents an attitude determination scheme for the Science and Technology Satellite-2(STSAT-2) using Fine Digital Sun Sensor(FDSS). The FDSS has been developed for STSAT-2, and exhibits the accuracy of 0.032degree in $1{\sigma}$. To be specific, the attitude information from the sensor is exploited to compensate for Fiber Optic Gyro(FOG) mounted on STSAT-2, and Kalman filter model is derived and implemented. To show the effectiveness of the present compensation scheme, computer simulations have been carried out resulting in the attitude errors within a bound.

Study on the Algorithm Characteristic of True North-Finding Utilizing 1-axis Gyro Sensor Equipment (1-축 자이로센서를 이용한 진북 추종 알고리즘 특성에 관한 연구)

  • Choi, Ju-Ho;Kwon, Young;Lee, Dae-Chul;Chung, Han-Shik;Jeong, Hyo-Min
    • Journal of Power System Engineering
    • /
    • v.19 no.3
    • /
    • pp.36-41
    • /
    • 2015
  • The true north-finding equipment utilizing gyro sensor is used for INS(Inertial Navigation System) and has an increasing preference for gyro compass system due to compact size, lightening, low power and price. The purpose of this experiment is to research gyro compass system providing high performance in the field of manned or unmanned gyro compass system which proposes the accuracy of 1% utilizing experimented equipment at true north of the earth. Unlike the conventional system, the proposed gyro sensor system indicates to be applied in the various and specific equipment using multiple technique and method.

HYPERSENSITIZATION FOR ASTRONOMICAL PHOTOGRAPHIC PLATES: IIIa-J, IIIa-F, 103a-O, 103a-D and IIa-O PLATES (천체 사진 건판의 초증감 처리 : IIIa-J, IIIa-F, 103a-O, 103a-D 및 IIa-O 건판)

  • Jeon, Yeong-Beom;Sim, Gyeong-Jin
    • Publications of The Korean Astronomical Society
    • /
    • v.8 no.1
    • /
    • pp.119-136
    • /
    • 1993
  • Optimum hypering conditions are found for IIIa-J, IIIa-F, 103a-O, 103a-D, and IIa-O plates using hypersensitization machine in KAO. For every experimental plate we get speed gain, fog increment, signal to noise ratio and relative DQE according to hypering time and temperature. The hypersensitization method is baking with 8% hydrogen mixed gas. For IIIa-J, 103a-O, and 103a-D plates treated $65^{\circ}C$, 3 hours baking, the speed gains arc increased by about 10 times, 2 times, and 2 times compared to untreated plates, respectively. The fogs are increased by 0.08, 0.10, and 0.08, respectively. For IIIa-F, IIa-O plates treated $65^{\circ}C$, 2 hours baking, the speed gains are increased by about 4.7 times and 1.8 times compared to untreated plates, respectively. The fogs are increased by 0.15 and 0.04, respectively.

  • PDF