• Title/Summary/Keyword: Communication shadow area

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T-DMB System Based on Limited Reception Function (제한수신 기능 기반 T-DMB 시스템)

  • Lee, Jong-Won;Kang, In-Shik;Yu, Dae-Sang;Kim, Jong-Moon;Jung, Hoe-Kyung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.5
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    • pp.957-962
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    • 2016
  • Current terrestrial Digital Multimedia Broadcasting (T-DMB) is conducting the emergency alert broadcast, or can view a variety of broadcasting. However, propagation shadow area is a situation where the service is limited due to limitations of facilities investment. In addition, there is the problem of T-DMB broadcasting is for viewing only a restricted area and a mobile device because the mobile is also T-DMB viewing device impossible. In this paper, it receives a T-DMB broadcasting as a way to solve the problems of the T-DMB system, which was studied the re transmission to the mobile device. Accordingly, by receiving the broadcast may be watched in the mobile device the T-DMB reception impossible. Also provides a one-way/two-way authentication mechanism using a conditional access function, and the system was configured so that the user can watch only the registered broadcasting.

Addressing and Routing Method for Zigbee Network Expansion (Zigbee 기반 네트워크의 확장을 위한 어드레스 방식과 라우팅 방법)

  • Choi, Sung-Chul;Jeong, Woo-Jeong;Kim, Tae-Ho;Jeong, Kyu-Seuck;Kim, Jong-Heon;Lee, In-Sung
    • The Journal of the Korea Contents Association
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    • v.9 no.7
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    • pp.57-66
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    • 2009
  • Zigbee is a universal communication standard used in USN and is utilized in various applications. Zigbee protocol provides an address within a single PAN network, and at this time, it uses DAA. This is a method that divides a 16-bit address area into blocks with a fixed size according to the depth to assign one to each node. However, this method is limited because it has to assign addresses in 16 bits. As the depth increases, the number of nodes also increases exponentially to the maximal number of routers provided to each depth. Therefore, it is difficult to construct a huge network with numerous routers and large depth as in the places which are wide or have many shadow areas. Besides, since all the operations are performed in a single PAN network, it is hard to make several PANs into a single network. This article suggests new addressing and routing methods that can construct several PAN networks into a single network and combine broad area with less limitation in the number of routers and depth by extending the Zigbee-based network. Moreover, this paper has tested its performance and has verified its usability through substantive tests.

A Design and Implementation of Control and Management System for Water Culture Device using Solar Tracking Method (광원 트래킹 기법을 이용한 수경재배기 제어 관리 시스템 설계 및 구현)

  • Park, Sung-Kyun;Jung, Se-Hoon;Oh, Min-Joo;Sim, Chun-Bo;Park, Dong-Gook;You, Kang-Soo
    • The Journal of the Korea institute of electronic communication sciences
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    • v.9 no.2
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    • pp.231-242
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    • 2014
  • It is throwing the spotlight on the cultivation crops about high quality crops and productivity improvement per unit area because of rapid climate change caused by global warming. Therefore, we propose a water culture management of circulation nutrient method control system applies to solar tracking method not using traditional method of deep flow technique and artificial light source. We design it in the form of the circulation nutrient method in waterway of a certain amount of nutrient solution and water flowed into the way of circular. In addition, we design a multistage structure in pyramid shape which be possible continuous photosynthesis action to crops of water culture bottom part. Also, solar tracking method is designed five sensor method of center hole sensor method for tracking shadow of solar light not using traditional two hole, four hole sensor method. Finally, through the water culture device applies to solar light tracking method was not introduced in existing study yet, we can reduce growth speed of crops which be possible continuous photosynthesis action to crops. Moreover, We can expect high productivity of per unit area which be possible all crops can be offered growth environment of same type by using form of pyramid shape of multistage structure without top or bottom part.

Ultrasonographic Diagnosis of Subcutaneous Wooden Foreign Body (피하 조직에 발생한 나무 이물의 초음파 진단)

  • Choi, Ji-Hye;Keh, Seo-Yeon;Kim, Sung-Soo;Kim, Hye-Jin;Jang, Jae-Young;Choi, Hee-Yeon;Yoon, Jung-Hee
    • Journal of Veterinary Clinics
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    • v.28 no.1
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    • pp.163-172
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    • 2011
  • Subcutaneous foreign body causes recurrent problems such as chronic soft tissue swelling and discharge. Wooden foreign body is one of the most common foreign bodies found in subcutaneous region including face, interdigit, and thoracic or abdominal area. This report demonstrated three dogs with wooden foreign body located in subcutaneous region of thoracic wall, abdominal wall and upper eyelid, respectively. Three dogs showed prominent soft tissue swelling adjacent the foreign body. A sinus or drainage tract was developed in two of these dogs. Ultrasonography revealed that hyperechoic linear structure accompanied acoustic shadow in all dogs, and which was diagnosed as a subcutaneous foreign body. Anechoic or hyperechoic fluid and hypoechoic tissue circumscribed the foreign body. A subcutaneous foreign body in case 3 was removed by clamp under ultrasound-guide with sedation. Sinography was performed in case 1 and clarified that the wooden foreign body did not perforate the thoracic wall and there was no direct communication into thoracic cavity. Ultrasonography and sinography can be used to identify the subcutaneous foreign body and evaluate the inflammatory reaction and relationship between foreign body and adjacent structures.

A Study on the Improvement of Skin Loss Area in Skin Color Extraction for Face Detection (얼굴 검출을 위한 피부색 추출 과정에서 피부색 손실 영역 개선에 관한 연구)

  • Kim, Dong In;Lee, Gang Seong;Han, Kun Hee;Lee, Sang Hun
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.1-8
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    • 2019
  • In this paper, we propose an improved facial skin color extraction method to solve the problem that facial surface is lost due to shadow or illumination in skin color extraction process and skin color extraction is not possible. In the conventional HSV method, when facial surface is brightly illuminated by light, the skin color component is lost in the skin color extraction process, so that a loss area appears on the face surface. In order to solve these problems, we extract the skin color, determine the elements in the H channel value range of the skin color in the HSV color space among the lost skin elements, and combine the coordinates of the lost part with the coordinates of the original image, To minimize the number of In the face detection process, the face was detected using the LBP Cascade Classifier, which represents texture feature information in the extracted skin color image. Experimental results show that the proposed method improves the detection rate and accuracy by 5.8% and 9.6%, respectively, compared with conventional RGB and HSV skin color extraction and face detection using the LBP cascade classifier method.

Damage Detection and Classification System for Sewer Inspection using Convolutional Neural Networks based on Deep Learning (CNN을 이용한 딥러닝 기반 하수관 손상 탐지 분류 시스템)

  • Hassan, Syed Ibrahim;Dang, Lien-Minh;Im, Su-hyeon;Min, Kyung-bok;Nam, Jun-young;Moon, Hyeon-joon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.3
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    • pp.451-457
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    • 2018
  • We propose an automatic detection and classification system of sewer damage database based on artificial intelligence and deep learning. In order to optimize the performance, we implemented a robust system against various environmental variations such as illumination and shadow changes. In our proposed system, a crack detection and damage classification method using a deep learning based Convolutional Neural Network (CNN) is implemented. For optimal results, 9,941 CCTV images with $256{\times}256$ pixel resolution were used for machine learning on the damaged area based on the CNN model. As a result, the recognition rate of 98.76% was obtained. Total of 646 images of $720{\times}480$ pixel resolution were extracted from various sewage DB for performance evaluation. Proposed system presents the optimal recognition rate for the automatic detection and classification of damage in the sewer DB constructed in various environments.

Retrieving Volcanic Ash Information Using COMS Satellite (MI) and Landsat-8 (OLI, TIRS) Satellite Imagery: A Case Study of Sakurajima Volcano (천리안 위성영상(MI)과 Landsat-8 위성영상(OLI, TIRS)을 이용한 화산재 정보 산출: 사쿠라지마 화산의 사례연구)

  • Choi, Yoon-Ho;Lee, Won-Jin;Park, Sun-Cheon;Sun, Jongsun;Lee, Duk Kee
    • Korean Journal of Remote Sensing
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    • v.33 no.5_1
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    • pp.587-598
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    • 2017
  • Volcanic ash is a fine particle smaller than 2 mm in diameters. It falls after the volcanic eruption and causes various damages to transportation, manufacturing industry and respiration of living things. Therefore diffusion information of volcanic ash is highly significant for preventing the damages from it. It is advantageous to utilize satellites for observing the widely diffusing volcanic ash. In this study volcanic ash diffusion information about two eruptions of Mt. Sakurajima were calculated using the geostationary satellite, Communication, Ocean and Meteorological Satellite (COMS) Meteorological Imager (MI) and polar-orbiting satellite, Landsat-8 Operational Land Imager (OLI) and the Thermal InfraRed Sensor (TIRS). The direction and velocity of volcanic ash diffusion were analyzed by extracting the volcanic ash pixels from COMS-MI images and the height was retrieved by adjusting the shadow method to Landsat-8 images. In comparison between the results of this study and those of Volcanic Ash Advisories center (VAAC), the volcanic ash tend to diffuse the same direction in both case. However, the diffusion velocity was about four times slower than VAAC information. Moreover, VAAC only provide an ash height while our study produced a variety of height information with respect to ash diffusion. The reason for different results is measured location. In case of VAAC, they produced approximate ash information around volcano crater to rapid response, while we conducted an analysis of the ash diffusion whole area using ash observed images. It is important to measure ash diffusion when large-scale eruption occurs around the Korean peninsula. In this study, it can be used to produce various ash information about the ash diffusion area using different characteristics satellite images.