• Title/Summary/Keyword: Fog detection

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A Research on the Improvement of Visibility Using Low Deck Lighting in Bad Weather (악천후 시 낮은 도로조명을 이용한 도로 시인성 향상에 대한 연구)

  • Nam, Ki Ho;Kim, Chung Hyeok;Nam, Ki Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.33 no.3
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    • pp.186-193
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    • 2020
  • We investigate a fog-detection CCT control system using low deck lighting as a solution to the forward visibility of pole-type street lamps employed on existing roads. The lighting standards were met with a light source that has less compared with those of pole-type street lamps. The results show that the transmission rate was increased by changing the color temperature by automatically recognizing fog in bad weather and minimizing the phenomenon of lighting. In addition, it was allowed to create a safer and more comfortable driving environment for drivers owing to flicker or light pollution of existing pole-type street lamps. As a result, if lighting is used at a lower level than pole-type street lamps, the accident rate caused by securing the driver's forward visibility can be reduced sharply and existing problems can be resolved.

Detecting Jaywalking Using the YOLOv5 Model

  • Kim, Hyun-Tae;Lee, Sang-Hyun
    • International Journal of Advanced Culture Technology
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    • v.10 no.2
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    • pp.300-306
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    • 2022
  • Currently, Korea is building traffic infrastructure using Intelligent Transport Systems (ITS), but the pedestrian traffic accident rate is very high. The purpose of this paper is to prevent the risk of traffic accidents by jaywalking pedestrians. The development of this study aims to detect pedestrians who trespass using the public data set provided by the Artificial Intelligence Hub (AIHub). The data set uses training data: 673,150 pieces and validation data: 131,385 pieces, and the types include snow, rain, fog, etc., and there is a total of 7 types including passenger cars, small buses, large buses, trucks, large trailers, motorcycles, and pedestrians. has a class format of Learning is carried out using YOLOv5 as an implementation model, and as an object detection and edge detection method of an input image, a canny edge model is applied to classify and visualize human objects within the detected road boundary range. In this study, it was designed and implemented to detect pedestrians using the deep learning-based YOLOv5 model. As the final result, the mAP 0.5 showed a real-time detection rate of 61% and 114.9 fps at 338 epochs using the YOLOv5 model.

Genetic Algorithm based hyperparameter tuned CNN for identifying IoT intrusions

  • Alexander. R;Pradeep Mohan Kumar. K
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.3
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    • pp.755-778
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    • 2024
  • In recent years, the number of devices being connected to the internet has grown enormously, as has the intrusive behavior in the network. Thus, it is important for intrusion detection systems to report all intrusive behavior. Using deep learning and machine learning algorithms, intrusion detection systems are able to perform well in identifying attacks. However, the concern with these deep learning algorithms is their inability to identify a suitable network based on traffic volume, which requires manual changing of hyperparameters, which consumes a lot of time and effort. So, to address this, this paper offers a solution using the extended compact genetic algorithm for the automatic tuning of the hyperparameters. The novelty in this work comes in the form of modeling the problem of identifying attacks as a multi-objective optimization problem and the usage of linkage learning for solving the optimization problem. The solution is obtained using the feature map-based Convolutional Neural Network that gets encoded into genes, and using the extended compact genetic algorithm the model is optimized for the detection accuracy and latency. The CIC-IDS-2017 and 2018 datasets are used to verify the hypothesis, and the most recent analysis yielded a substantial F1 score of 99.23%. Response time, CPU, and memory consumption evaluations are done to demonstrate the suitability of this model in a fog environment.

Experimental and Analytical Study on the Water Level Detection and Early Warning System with Intelligent CCTV (지능형 CCTV를 이용한 수위감지 경보시스템에 대한 실험 및 해석적 연구)

  • Hong, Sangwan;Park, Youngjin;Lee, Hacheol
    • Journal of the Society of Disaster Information
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    • v.10 no.1
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    • pp.105-115
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    • 2014
  • In this research, we developed video analytic algorithms to detect water-level automatically and a system for proactive alarming using intelligent CCTV cameras. We applied these algorithms and a system to test-beds and verified for practical use. We made camera-selection policies and operation plans to keep the detection accuracy high and to optimize the suitability for the ever-changing weather condition, while the environmental factors such as camera shaking and weather condition can affect to detection accuracy. The estimation result of algorithms showed 90% detection accuracy for all CCTV camera types. For water level detection, NIR camera performed great. NIR camera performed over 95% accuracy in day or night, suitable in natural weather condition such as shaking condition, fog, and low light, needs similar installment skills with common cameras, and spends only 15% high cost. As a result, we practically tested water level detection algorithms and operation system based on intelligent CCTV camera. Furthermore, we expect the positive evidences when it is applied for public use.

Lane Detection for Adaptive Control of Autonomous Vehicle (지능형 자동차의 적응형 제어를 위한 차선인식)

  • Kim, Hyeon-Koo;Ju, Yeonghwan;Lee, Jonghun;Park, Yongwan;Jeong, Ho-Yeol
    • IEMEK Journal of Embedded Systems and Applications
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    • v.4 no.4
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    • pp.180-189
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    • 2009
  • Currently, most automobile companies are interested in research on intelligent autonomous vehicle. They are mainly focused on driver's intelligent assistant and driver replacement. In order to develop an autonomous vehicle, lateral and longitudinal control is necessary. This paper presents a lateral and longitudinal control system for autonomous vehicle that has only mono-vision camera. For lane detection, we present a new lane detection algorithm using clothoid parabolic road model. The proposed algorithm in compared with three other methods such as virtual line method, gradient method and hough transform method, in terms of lane detection ratio. For adaptive control, we apply a vanishing point estimation to fuzzy control. In order to improve handling and stability of the vehicle, the modeling errors between steering angle and predicted vanishing point are controlled to be minimized. So, we established a fuzzy rule of membership functions of inputs (vanishing point and differential vanishing point) and output (steering angle). For simulation, we developed 1/8 size robot (equipped with mono-vision system) of the actual vehicle and tested it in the athletics track of 400 meter. Through the test, we prove that our proposed method outperforms 98 % in terms of detection rate in normal condition. Compared with virtual line method, gradient method and hough transform method, our method also has good performance in the case of clear, fog and rain weather.

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A Framework for Object Detection by Haze Removal (안개 제거에 의한 객체 검출 성능 향상 방법)

  • Kim, Sang-Kyoon;Choi, Kyoung-Ho;Park, Soon-Young
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.5
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    • pp.168-176
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    • 2014
  • Detecting moving objects from a video sequence is a fundamental and critical task in video surveillance, traffic monitoring and analysis, and human detection and tracking. It is very difficult to detect moving objects in a video sequence degraded by the environmental factor such as fog. In particular, the color of an object become similar to the neighbor and it reduces the saturation, thus making it very difficult to distinguish the object from the background. For such a reason, it is shown that the performance and reliability of object detection and tracking are poor in the foggy weather. In this paper, we propose a novel method to improve the performance of object detection, combining a haze removal algorithm and a local histogram-based object tracking method. For the quantitative evaluation of the proposed system, information retrieval measurements, recall and precision, are used to quantify how well the performance is improved before and after the haze removal. As a result, the visibility of the image is enhanced and the performance of objects detection is improved.

Lane detection method using the Retinex algorithm in foggy roads (Retinex 알고리즘을 사용한 안개 구간에서의 차선 검출 방법)

  • Kang, ji-hun;Choi, seo-hyuk;Kim, chang-dae;Ryu, sung-pil;Kim, dong-woo;Ahn, jae-hyeong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.05a
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    • pp.376-380
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    • 2015
  • This paper proposes new recognition method of road lanes misty day. The method enables autonomous-driving of cars and the safety of the drivers while driving with bad visibility in foggy roads. The proposed method, firstly, determines whether the foggy or not according to pixel number distributions and starting point of the fog period from input images. If it is foggy then the median filter's size of the Retinex algorithm is set to 1000 or more and it performs histogram equalization and normalization. The computer simulation results show that the proposed method can recognize better long distances and fine detection than earlier methods.

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Image-based fire area segmentation method by removing the smoke area from the fire scene videos (화재 현장 영상에서 연기 영역을 제외한 이미지 기반 불의 영역 검출 기법)

  • KIM, SEUNGNAM;CHOI, MYUNGJIN;KIM, SUN-JEONG;KIM, CHANG-HUN
    • Journal of the Korea Computer Graphics Society
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    • v.28 no.4
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    • pp.23-30
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    • 2022
  • In this paper, we propose an algorithm that can accurately segment a fire even when it is surrounded by smoke of a similar color. Existing fire area segmentation algorithms have a problem in that they cannot separate fire and smoke from fire images. In this paper, the fire was successfully separated from the smoke by applying the color compensation method and the fog removal method as a preprocessing process before applying the fire area segmentation algorithm. In fact, it was confirmed that it segments fire more effectively than the existing methods in the image of the fire scene covered with smoke. In addition, we propose a method that can use the proposed fire segmentation algorithm for efficient fire detection in factories and homes.

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.

Clinical Application of $^{18}F-FDG$ PET in Gastric Cancer (위암에서 $^{18}F-FDG$ PET의 임상 이용)

  • Yun, Mi-Jin;Kim, Tae-Sung;Hwang, Hee-Sung
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.sup1
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    • pp.39-45
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    • 2008
  • PET or PET/CT detects only less than 50% of early gastric cancer and 62-98% of advanced gastric cancer. Therefore, mass screening programs are recommended for all adults over the age of 40 for early detection and early treatment of gastric cancer through endoscopy or various radiological tests. The most important step after diagnosis of gastric cancer is accurate staging, which mainly evaluates tumor resectability to avoid unnecessary surgery. Important factors that affect tumor resectability are whether the tumor can be separated from adjacent organs or important blood vessels, the extent of lymph node metastasis, presence of peritoneal metastasis, or distant organ metastasis. To evaluate the extent of local tumor invasion, anatomical imaging that has superior spatial resolution is essential. There are a few studies on prognostic significance of FDG uptake with inconsistent results between them. In spite of lower sensitivity for lymph node staging, the specificity of CT and PET are very high, and the specificity for PET tends to be higher than that for CT. Limited data published so far show that PET seems less useful in the detection of lung and bone metastasis. In the evaluation of pleural or peritoneal metastasis, PET seems very specific but insensitive as well. When FOG uptake of primary tumor is low, distant metastasis also tends to show low FDG uptake reducing its detection on PET. There are only a few data available in the evaluation of recurrence detection and treatment response using FDG PET or PET/CT.