• Title/Summary/Keyword: fog system

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Application of Heat Balance Model Design of Ventilating and Cooling Greenhouse (온실의 환기 및 냉방 설계를 위한 열평형 모델의 작용)

  • 남상운
    • Journal of Bio-Environment Control
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    • v.9 no.4
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    • pp.201-206
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    • 2000
  • A certain system to overcome high temperature should be introduced for the stable year-round cultivation in greenhouses. There are efficient methods to overcome high temperature such as ventilation system with shading screen, fan and pad system with screen, and fog system with screen. This study was carried out to find a means to determine the capacity of such system. Heat balance equations for each system were established and verified by experimental results. The calculated ventilation rates from heat balance equations showed a good agreement with the measured ones. The evapotranspiration coefficient was the most important parameter affecting the ventilation requirement among input parameter affecting the ventilation requirement among input parameters except weather data. When the evaportanspiration coefficient increased 1%, the ventilation requirement decreased 1.3%. Therefore the data of evapotranspiration coefficient should be accumulated by various experiments, and then design standards and selection guidelines should be provided. The simulation results for same design conditions shown that air exchanges requirement and evaporating water of fan and pad system were 5.1∼7.7% and 6.8∼9.3% larger than those of fog system, respectively.

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Development of the Weather Detection Algorithm using CCTV Images and Temperature, Humidity (CCTV 영상과 온·습도 정보를 이용한 기후검출 알고리즘 개발)

  • Park, Beung-Raul;Lim, Jong-Tea
    • Journal of Korea Multimedia Society
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    • v.10 no.2
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    • pp.209-217
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    • 2007
  • This paper proposed to a detection scheme of weather information that is a part of CCTV Images Weather Detection System using CCTV images and Temperature, Humidity. The previous Partial Weather Detection System uses how to acquire weather information using images on the Road. In the system the contrast and RGB Values using clear images are gained. This information is distributed a input images to cloud, rain, snow and fog images. That is, this information is compared the snow and the fog images for acquisition more correctness information us ing difference images and binary images. Currently, We use to environment sense system, but we suggest a new Weather Detection Algorithm to detect weather information using CCTV images. Our algorithm is designed simply and systematically to detect and separate special characteristics of images from CCTV images. and using temperature & humidity in formation. This algorithm, there is more complex to implement than how to use DB with high overhead of time and space in the previous system. But our algorithm can be implement with low cost' and can be use the system in real work right away. Also, our algorithm can detect the exact information of weather with adding in formation including temperature, humidity, date, and time. At last, this paper s how the usefulness of our algorithm.

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Driving Systems of the Fiber Optic Gyrocompass (광파이버 자이로콤파스 구동시스템에 관한 연구)

  • Kwon, Y.S.;Kim, S.J.;Lee, S.S.;Bae, J.C.;Lee, S.J.;Choi, W.J.
    • Proceedings of the KIEE Conference
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    • 1996.07a
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    • pp.124-126
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    • 1996
  • In this paper, the driving systems of the Fiber Optic Gyrocompass absolutely required a constant speed and a precise position control with fine step angle, are presented. One of the proposed systems is a stepping motor system with microstep driver, another one is a DC servo motor. Experimental results indicate that a low cost and simple FOG driving system using a stepping motor is capable of a satisfactory operation.

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The Study of Improve Safety for Signaling System using Communication (통신에 의한 신호시스템의 안전성 확보에 대한 연구)

  • 백종현;한성호;안태기;온정근
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.307-314
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    • 1999
  • The potential use of ranging sensors for reducing the occurrence of accidents in real environment is explored by many companies and laboratories. Most of the sensors under investigation utilize the FMCW(Frequency Modulated Continuous Wave) waveforms. The automotive environment presents to the FMCW radar sensor a multitude of moving and fixed targets and the sensor must detect and track only the targets which may pose a threat of collision or passengers accident. The sensor must function accurately in the presence of background echoes generated by moving and fixed targets, ground reflections, atmospheric noises, including rains, fog, and, snow and noise generated within the receiver. False detection of the desired target in this environment may issue false alarms. That may be dangerous to the passenger and the vehicle. A high false alarm rate is totally unacceptable. The false alarm mechanism consists of noise peaks, crossing the threshold and the undesired response of the system to off lane targets which are not potentially hazardous to the radar equipped vehicle. This paper presents an improve technique safety performance for driver-less operation using FMCW radar sensors.

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Study on the Design and Fabrication of e-Racon Antenna (e-Racon 안테나의 설계 및 제작 관련 연구)

  • Kim, Jae-Kwan;Guk, Sung-Kee;Kim, Min-Cheol;Jo, Tae-Gyun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2018.11a
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    • pp.127-129
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    • 2018
  • RadarBeacons are navigational equipment that helps the navigators avoid dangerous rocks, such as heavy fog, nighttime, etc. when ships operate, or when visibility is bad. The existing antenna was researching the development of the advanced radar eacon (Enhanced Radar Beacon) for improving the development of the next generation racon with the AIS (Automatic Identification System) function.

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An Intelligent Automatic Early Detection System of Forest Fire Smoke Signatures using Gaussian Mixture Model

  • Yoon, Seok-Hwan;Min, Joonyoung
    • Journal of Information Processing Systems
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    • v.9 no.4
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    • pp.621-632
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    • 2013
  • The most important things for a forest fire detection system are the exact extraction of the smoke from image and being able to clearly distinguish the smoke from those with similar qualities, such as clouds and fog. This research presents an intelligent forest fire detection algorithm via image processing by using the Gaussian Mixture model (GMM), which can be applied to detect smoke at the earliest time possible in a forest. GMMs are usually addressed by making the model adaptive so that its parameters can track changing illuminations and by making the model more complex so that it can represent multimodal backgrounds more accurately for smoke plume segmentation in the forest. Also, in this paper, we suggest a way to classify the smoke plumes via a feature extraction using HSL(Hue, Saturation and Lightness or Luminanace) color space analysis.

The Study of Improved Safety of Signalling System using Communication (통신에 의한 신호시스템의 안전성 확보에 관한 연구)

  • Baek, Jong-Hyen;Wang, Jong-Bae;Byun, Yeun-Sub;Park, Hyun-Jun;Han, Young-Jae;Kim, Kil-Dong
    • Proceedings of the KIEE Conference
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    • 2000.07b
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    • pp.1368-1370
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    • 2000
  • The automotive environment presents to the FMCW radar sensor a multitude of moving and fixed targets and the sensor must detect and track only the targets which may pose a threat of collision or passengers accident. The sensor must function accurately in the presence of background echoes generated by moving and fixed targets, ground reflections, atmospheric noises, including rains, fog, and, snow and noise generated within the receiver. False detection of the desired target in this environment may issue false alarms. That may be dangerous to the passenger and the vehicle. A high false alarm rate is totally unacceptable. The false alarm mechanism consists of noise peaks, crossing the threshold and the undesired response of the system to off lane targets which are not potentially hazardous to the radar equipped vehicle. This paper presents an improve technique safety performance for driver-less operation using FMCW radar sensors.

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Single Image Dehazing Using Dark Channel Prior and Minimal Atmospheric Veil

  • Zhou, Xiao;Wang, Chengyou;Wang, Liping;Wang, Nan;Fu, Qiming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.1
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    • pp.341-363
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    • 2016
  • Haze or fog is a common natural phenomenon. In foggy weather, the captured pictures are difficult to be applied to computer vision system, such as road traffic detection, target tracking, etc. Therefore, the image dehazing technique has become a hotspot in the field of image processing. This paper presents an overview of the existing achievements on the image dehazing technique. The intent of this paper is not to review all the relevant works that have appeared in the literature, but rather to focus on two main works, that is, image dehazing scheme based on atmospheric veil and image dehazing scheme based on dark channel prior. After the overview and a comparative study, we propose an improved image dehazing method, which is based on two image dehazing schemes mentioned above. Our image dehazing method can obtain the fog-free images by proposing a more desirable atmospheric veil and estimating atmospheric light more accurately. In addition, we adjust the transmission of the sky regions and conduct tone mapping for the obtained images. Compared with other state of the art algorithms, experiment results show that images recovered by our algorithm are clearer and more natural, especially at distant scene and places where scene depth jumps abruptly.

A Study on Modeling of Unmanned Gantry Crane (1) (UGC 모델링에 관한 연구(I))

  • 박경택;김두형;신영재;박찬훈;김용선
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 1999.10a
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    • pp.333-344
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    • 1999
  • Currently many studies on the unmanned gantry crane for the automated container terminal are accomplished. This is needed for the development of large scale, automation, high speed, unmanned system and information system in port facility. In order to do efficient container handling job in port yard, the automated handling system is well adapted to the job environments and all-season weather, In order to realize the automatic and unmanned system for container handling job, the required functions and main structure system are studied. The major problems of operation of the conventional gantry crane are that the vibration of gantry structure body is occurred by operation and that high-speed and precision position-velocity control and the capability to dope to the external disturbances caused by the wind, rain, fog and job environments. In this paper, the fundamental study for establishment of the concept and the dynamic modelling of the major sub system of the unmanned gantry crane is presented. These studies are useful for design and manufacturing of the new concept model of the unmanned gantry crane for efficient operation of the automated container terminal.

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Empirical Analysis on the Cooling Load and Evaporation Efficiency of Fogging System in Greenhouses (온실의 냉방부하 및 포그시스템의 증발효율 실험분석)

  • Nam, Sang-Woon;Seo, Dong-Uk;Shin, Hyun-Ho
    • Journal of Bio-Environment Control
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    • v.24 no.3
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    • pp.147-152
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    • 2015
  • In order to develop the cooling load estimation method in the greenhouse, the cooling load calculation formula based on the heat balance method was constructed and verified by the actual cooling load measured in the fog cooling greenhouse. To examine the ventilation heat transfer in the cooling load calculation formula, we measured ventilation rates in the experimental greenhouse which a cooling system was not operated. The ventilation heat transfer by a heat balance method showed a relatively good agreement. Evaporation efficiencies of the two-fluid fogging system were a range of 0.3 to 0.94, average 0.67, and it showed that they increased as the ventilation rate increased. We measured thermal environments in a fog cooling greenhouse, and calculated cooling load by heat balance equation. Also we calculated evaporative cooling energy by measuring the sprayed amount in the fogging system. And by comparing those two results, we could verify that the calculated and the measured cooling load showed a relatively similar trend. When the cooling load was low, the measured value was slightly larger than calculated, when the cooling load was high, it has been found to be smaller than calculated. In designing the greenhouse cooling system, the capacity of cooling equipment is determined by the maximum cooling load. We have to consider the safety factor when installed capacity is estimated, so a cooling load calculation method presented in this study could be applied to the greenhouse environmental design.