• Title/Summary/Keyword: Communication distance

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Co-saliency Detection Based on Superpixel Matching and Cellular Automata

  • Zhang, Zhaofeng;Wu, Zemin;Jiang, Qingzhu;Du, Lin;Hu, Lei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.5
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    • pp.2576-2589
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    • 2017
  • Co-saliency detection is a task of detecting same or similar objects in multi-scene, and has been an important preprocessing step for multi-scene image processing. However existing methods lack efficiency to match similar areas from different images. In addition, they are confined to single image detection without a unified framework to calculate co-saliency. In this paper, we propose a novel model called Superpixel Matching-Cellular Automata (SMCA). We use Hausdorff distance adjacent superpixel sets instead of single superpixel since the feature matching accuracy of single superpixel is poor. We further introduce Cellular Automata to exploit the intrinsic relevance of similar regions through interactions with neighbors in multi-scene. Extensive evaluations show that the SMCA model achieves leading performance compared to state-of-the-art methods on both efficiency and accuracy.

Robust Image Hashing for Tamper Detection Using Non-Negative Matrix Factorization

  • Tang, Zhenjun;Wang, Shuozhong;Zhang, Xinpeng;Wei, Weimin;Su, Shengjun
    • Journal of Ubiquitous Convergence Technology
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    • v.2 no.1
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    • pp.18-26
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    • 2008
  • The invariance relation existing in the non-negative matrix factorization (NMF) is used for constructing robust image hashes in this work. The image is first re-scaled to a fixed size. Low-pass filtering is performed on the luminance component of the re-sized image to produce a normalized matrix. Entries in the normalized matrix are pseudo-randomly re-arranged under the control of a secret key to generate a secondary image. Non-negative matrix factorization is then performed on the secondary image. As the relation between most pairs of adjacent entries in the NMF's coefficient matrix is basically invariant to ordinary image processing, a coarse quantization scheme is devised to compress the extracted features contained in the coefficient matrix. The obtained binary elements are used to form the image hash after being scrambled based on another key. Similarity between hashes is measured by the Hamming distance. Experimental results show that the proposed scheme is robust against perceptually acceptable modifications to the image such as Gaussian filtering, moderate noise contamination, JPEG compression, re-scaling, and watermark embedding. Hashes of different images have very low collision probability. Tampering to local image areas can be detected by comparing the Hamming distance with a predetermined threshold, indicating the usefulness of the technique in digital forensics.

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Interference Mitigation Scheme by Antenna Selection in Device-to-Device Communication Underlaying Cellular Networks

  • Wang, Yuyang;Jin, Shi;Ni, Yiyang;Wong, Kai-Kit
    • Journal of Communications and Networks
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    • v.18 no.3
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    • pp.429-438
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    • 2016
  • In this paper, we investigate an interference mitigation scheme by antenna selection in device-to-device (D2D) communication underlaying downlink cellular networks. We first present the closed-form expression of the system achievable rate and its asymptotic behaviors at high signal-to-noise ratio (SNR) and the large antenna number scenarios. It is shown that the high SNR approximation increases with more antennas and higher ratio between the transmit SNR at the base station (BS) and the D2D transmitter. In addition, a tight approximation is derived for the rate and we reveal two thresholds for both the distance of the D2D link and the transmit SNR at the BS above which the underlaid D2D communication will degrade the system rate. We then particularize on the small cell setting where all users are closely located. In the small cell scenario, we show that the relationship between the distance of the D2D transmitting link and that of the D2D interfering link to the cellular user determines whether the D2D communication can enhance the system achievable rate. Numerical results are provided to verify these results.

Distance measurement using Zigbee communication solution (Zigbee 통신 solution을 이용한 거리 측정)

  • Kim, Young-Keun;Hur, Chang-Wu
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.10
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    • pp.1830-1834
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    • 2008
  • At the present day, devices for measurement and control of data by wireless based computer have been generalized. The devices with low cost and high performance have been spotlighted. If Zigbee communication solution is used in dangerous places and places that can not in use wire communication, computer can process data without limitation. Zigbee communication solution is effective in power consumption as compared with RF or bluetooth and can use battery. System cost of Zigbee also is very low, so can install lots of nodes. The system made in this paper transmit by wireless many LMCs(Laser Measuring Control) of wireless transmission system for distance measurement and many slave Zigbee to a master Zigbee.

CO-CLUSTER HOMOTOPY QUEUING MODEL IN NONLINEAR ALGEBRAIC TOPOLOGICAL STRUCTURE FOR IMPROVING POISON DISTRIBUTION NETWORK COMMUNICATION

  • V. RAJESWARI;T. NITHIYA
    • Journal of applied mathematics & informatics
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    • v.41 no.4
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    • pp.861-868
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    • 2023
  • Nonlinear network creates complex homotopy structural communication in wireless network medium because of complex distribution approach. Due to this multicast topological connection structure, the queuing probability was non regular principles to create routing structures. To resolve this problem, we propose a Co-cluster homotopy queuing model (Co-CHQT) for Nonlinear Algebraic Topological Structure (NLTS-) for improving poison distribution network communication. Initially this collects the routing propagation based on Nonlinear Distance Theory (NLDT) to estimate the nearest neighbor network nodes undernon linear at x(a,b)→ax2+bx2 = c. Then Quillen Network Decomposition Theorem (QNDT) was applied to sustain the non-regular routing propagation to create cluster path. Each cluster be form with co variance structure based on Two unicast 2(n+1)-Z2(n+1)-Z network. Based on the poison distribution theory X(a,b) ≠ µ(C), at number of distribution routing strategies weights are estimated based on node response rate. Deriving shorte;'l/st path from behavioral of the node response, Hilbert -Krylov subspace clustering estimates the Cluster Head (CH) to the routing head. This solves the approximation routing strategy from the nonlinear communication depending on Max- equivalence theory (Max-T). This proposed system improves communication to construction topological cluster based on optimized level to produce better performance in distance theory, throughput latency in non-variation delay tolerant.

Development of Ground Antenna Tracker for Drones Based on Satellite System (위성시스템 기반 드론용 지상 안테나 트래커 개발)

  • Se-jun Kim;Jong-pil Choi;Dong-huyn Oh;Da-jin-sol Kim
    • Journal of Advanced Navigation Technology
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    • v.27 no.6
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    • pp.740-745
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    • 2023
  • This study proposes the development of an antenna tracker system using a satellite system to stabilize the communication status of drones and extend the communication distance. The location information of the drone and the ground station was used to maximize communication gain in the general fixed antenna method between the ground station and the drone. We developed a tracker system that can automatically and continuously aim the ground station's antenna at the drone. It is expected that the use of antenna trackers will improve the stabilization of communication conditions and expand the communication distance, thereby leading to the advancement of the drone industry.

A Study on Data Acquisition in the Invisible Zone of UAV through LTE Remote Control (LTE 원격관제를 통한 UAV의 비가시권 데이터 취득방안)

  • Jeong, HoHyun;Lee, Jaehee;Park, Seongjin
    • Korean Journal of Remote Sensing
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    • v.35 no.6_1
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    • pp.987-997
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    • 2019
  • Recently the demand for drones is rapidly increasing, as developing Unmanned Aerial Vehicle (UAV) and growing interest in them. Compared to traditional satellite and aerial imagery, it can be used for various researches (environment, geographic information, ocean observation, and remote sensing) because it can be managed with low operating costs and effective data acquisition. However, there is a disadvantage in that only a small area is acquired compared to the satellite and an aircraft, which is a traditional remote sensing method, depending on the battery capacity of the UAV, and the distance limit between Ground Control System (GCS) and UAV. If remote control at long range is possible, the possibility of using UAV in the field of remote sensing can be increased. Therefore, there is a need for a communication network system capable of controlling regardless of the distance between the UAV and the GCS. The distance between UAV and GCS can be transmitted and received using simple radio devices (RF 2.4 GHz, 915 MHz, 433 MHz), which is limited to around 2 km. If the UAV can be managed simultaneously by improving the operating environment of the UAV using a Long-Term Evolution (LTE) communication network, it can make greater effects by converging with the existing industries. In this study, we performed the maximum straight-line distance 6.1 km, the test area 2.2 ㎢, and the total flight distance 41.75 km based on GCS through LTE communication. In addition, we analyzed the possibility of disconnected communication through the base station of LTE communication.

A Study On Female high-School Students' Reactive Characteristics to PSCD and Their Parent-Child Communication (여고생의 동그라미중심 부모-자녀 그림(PSCD) 반응특성과 부모-자녀 의사소통에 관한 연구)

  • Kim, Gab-Sook;Jeon, Young-Sook
    • Korean Journal of Human Ecology
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    • v.16 no.5
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    • pp.921-932
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    • 2007
  • This study is to examine the relationship between their parent-child communication and their reactive characteristics to the PSCD(Parent-Self-Centered-Drawing) test of the Female high-School Students. The study subjects are 209 Female high-School Students, and research tools are PSCD test and a measure of parent-child communication. The data were analyzed with a paired t-test, one-way ANOVA and Scheffe's post-hoc test. Results are as follows. First, they perceived positively communication toward mother more than communication toward father. Second, as for communication toward father according to the subjects' reaction to the father figure, female students show difference in ommission of facial parts, ommission of body parts, balance of body parts, facial expression and positive and negative symbols. Third, as for communication toward mother according to the subjects' reaction to the mother figure, female students show difference in ommission of facial parts, ommission of body parts, balance of body parts, facial expression and negative symbols. Forth, according to the female students' reaction to the self figure, they show different levels of communication toward father and self in regard of facial expression and distance between the figures. On the other hand, they show different levels of communication toward mother with respect to ommission of facial parts, ommission of body parts, balance of body parts, facial expression and distance between the figures. The authors conclude that the PSCD is a useful tool for measuring the level of parent-child communication.

Study of Modulation Effect in Integrated Interface Under Controlling Switching Light-Emitting Diode Lighting Module

  • Hong, Geun-Bin;Jang, Tae-Su;Kim, Yong-Kab
    • Transactions on Electrical and Electronic Materials
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    • v.12 no.6
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    • pp.253-257
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    • 2011
  • This study was carried out to solve problems such as radio frequency band depletion, confusion risk, and security loss in existing visible wireless communication systems, and to determine the applicability of next-generation networks. A light-emitting diode (LED) light communication system was implemented with a controlling switching light module using the ATmega16 micro-controller. To solve the existing modulation effect and disturbance in visible light communication, an integrated interface was evaluated with a driving light module and analyzes its reception property. A transmitter/receiver using the ATmel's micro-controller, high-intensity white LED-6 modules, and infrared sensor KSM60WLM and visible sensor TSL250RD were designed. An experiment from the initial value of distance to 2.5 m showed 0.46 V of the voltage loss, and if in long distance, external light interference occurred and light intensity was lost by external impact and thus data had to be modified or reset repeatedly. Additionally, when we used 6 modules through the remote controller's lighting dimming, data could be transmitted up to 1.76 m without any errors during the day and up to 2.29 m at night with around 2~3% communication error. If a special optical filter can reduce as much external light as possible in the integrated interface, the LED for lighting communication systems may be applied in next generation networks.

RFID Tag Antenna for Metallic Objects

  • Lee, Sang-On;Chung, You-Chung;Kim, Sin-Hwan;Lee, Chang-Sic
    • Proceedings of the Korea Society of Information Technology Applications Conference
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    • 2005.11a
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    • pp.267-270
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    • 2005
  • An RFID patch antenna for metallic object has been designed. The effects of variation of distance between the tag antenna and ground of the antenna have been studied. Various dielectric constants, thickness, permittivity, width of transmission line and length of transmission line have been used to design the better tag antenna for metallic object.

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