• Title/Summary/Keyword: communication networks

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A Design of Block-wise Inpainting Scheme for Packet Error Concealment (패킷에러로 인한 영상손실을 최소화하기 위한 블록기반의 인페인팅 알고리즘의 설계)

  • Feng, Liu;Han, Ngoc Son;Kim, Seong Whan
    • Annual Conference of KIPS
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    • 2009.11a
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    • pp.349-350
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    • 2009
  • In this paper, we describe an error concealment techniques based on image inpainting for the image impairments due to the packet loss. Image inpainting is to remove or restore the damaged sections from the images, which is usually old images, paintings, or video films. Inpainting has a long history which goes back to the era when the paintings come out. Manual inpainting is no more used, and we can use digital inpainting for the digitally impaired images and video sequences. In this paper, we review the error concealment techniques for the packet loss recovery and propose our inpainting based image impairment recovery scheme for video communication over packet networks.

Reservation-Based TDMA Protocol for Emergency Transmission in Medical Body Area Network Protocol (Medical Body Area Network에서 긴급전송을 위한 예약기반 TDMA 프로토콜)

  • Kim, Kyung-Jun;Kim, Chul-Won
    • Annual Conference of KIPS
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    • 2009.04a
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    • pp.1359-1362
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    • 2009
  • 센서 네트워크의 저전력 단거리 무선통신의 특징을 의료분야에 적용한 의료용 네트워크(Medical Body Area Networks)는 사람의 인체를 진단하기 위한 소형 의료 디바이스들간의 연결성을 제공하기위해 최근 주목받고 있는 기술이다. 본 논문에서 제안하는 프로토콜은 MBAN에서 전력의 효율성 및 신뢰성에 초점을 맞추어 제안 하였다. IEEE 802.15.3의 MCTA를 MBAN에서 적용 가능한 SR-MCTA로 변형하여 전송의 신뢰성 및 전력 사용의 효율성을 고려한 프로토콜을 제안한다. 제안하는 프로토콜에서 SR-MCTA 슬롯은 단말 디바이스의 요청에 의해 MBAN 코디네이터가 할당하며, 할당하는 방법은 현재 슬롯에서 긴급 패킷이 발생할 때 임이의 충돌 패킷을 발생시켜 서 패킷을 획득하는 방법을 사용한다. 이를 위해 WBAN 네트워크내의 특정 노드를 클러스터의 헤드로 설정한다. 제안하는 프로토콜의 효율성 분석을 통하여 제안하는 방법이 전송의 지연 개선 및 에너지 효율적임을 보였다.

A Reliable Code Dissemination Protocol Using Congestion Control in Wireless Sensor Networks (무선 센서 네트워크 상에서 혼잡제어기법을 이용한 신뢰성있는 코드 전파 프로토콜)

  • Cha, Jeong Woo;Kim, Il Hyu;Kim, Chang Hoon;Kim, Hiecheol
    • Annual Conference of KIPS
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    • 2009.04a
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    • pp.716-719
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    • 2009
  • 소프트웨어 업데이트를 위한 업데이트 코드 전파 기법은 매우 중요한 기술 중 하나이다. 본 논문에서는 기존에 제안한 네트워크 코딩기법을 이용한 코드 전파 기법의 문제점을 파악하고 그 문제점을 해결하기 위해 혼잡 제어 기법을 이용한 코드 전파 기법을 제안한다. 제안된 코드 전파 기법은 네트워크 코딩 기법을 적용한 코드 전파 기법의 문제점인 Broadcasting시 발생된 문제점을 해결하여 00%의 성능 향상을 보인다. 뿐만 아니라 본 논문에서 제안한 방식은 혼잡 제어의 Bottle-neck 문제점을 Broadcasting 방식에 Sector를 나누고 우선순위 방식을 이용함으로써 신뢰성있는 데이터 전송을 가능하게 한다.

AN ARTIFICIAL NEURAL NETWORK MODEL FOR THE CONDITION RATING OF BRIDGES

  • Jaeho Lee;Kamal Sanmugarasa;Michael Blumenstein
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.533-538
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    • 2005
  • An outline of an Artificial Neural Network (ANN) model for bridge condition rating and the results of a pilot study are presented in this paper. Most BMS implementation systems involve an extensive range of data collection to operate accurately. It takes many years to effectively implement a BMS using existing methodologies. This is due to unmatched data requirements. Such problems can be overcome by adopting the ANN model presented in this paper. The objective of the proposed model is to predict bridge condition ratings using historical bridge inspection data for effective BMS operation.

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Steganography: A Flexible Embedded Randomization Technique

  • Khaled H., Abuhmaidan;Ahmad K., Kayed;Maryam, Alrisia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.1
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    • pp.120-144
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    • 2023
  • With the expansion of digital communication networks, a considerable number of randomization techniques have been invented and implemented to enhance the different data transmission algorithms' levels of security. Steganography is among the data transmissions techniques used to hide secret data. Nowadays, several randomization techniques have been used in steganography to elevate the security of transmitted data. Unfortunately, the majority of these techniques lack some simplicity, efficiency, and flexibility, in addition to other limitations. This research presents a new randomization technique called Rand-Stego. Rand-Stego could be applied/practiced over any steganography technique. It provides simplicity and efficiency and elevates the security level. Examples of implementing the proposed technique on some steganography algorithms will be explored. The proposed and current techniques will be compared. The obtained results show Rand-Stego's superiority in terms of efficiency and flexibility when compared to the current techniques.

Neurons-on-a-Chip: In Vitro NeuroTools

  • Hong, Nari;Nam, Yoonkey
    • Molecules and Cells
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    • v.45 no.2
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    • pp.76-83
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    • 2022
  • Neurons-on-a-Chip technology has been developed to provide diverse in vitro neuro-tools to study neuritogenesis, synaptogensis, axon guidance, and network dynamics. The two core enabling technologies are soft-lithography and microelectrode array technology. Soft lithography technology made it possible to fabricate microstamps and microfluidic channel devices with a simple replica molding method in a biological laboratory and innovatively reduced the turn-around time from assay design to chip fabrication, facilitating various experimental designs. To control nerve cell behaviors at the single cell level via chemical cues, surface biofunctionalization methods and micropatterning techniques were developed. Microelectrode chip technology, which provides a functional readout by measuring the electrophysiological signals from individual neurons, has become a popular platform to investigate neural information processing in networks. Due to these key advances, it is possible to study the relationship between the network structure and functions, and they have opened a new era of neurobiology and will become standard tools in the near future.

The Role of Political Agreement and Disagreement of News and Political Discussion on Social Media for Political Participation

  • Hyun, Kideuk
    • Analyses & Alternatives
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    • v.2 no.2
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    • pp.31-66
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    • 2018
  • This study investigates the mobilizing function of political agreement and disagreement in communition mediated by social media. Analyses of a survey found that reception of news consistent with individual political predispositions through social networking sites (SNS) positively related to political participation, whereas reception of counterattitudinal news was unrelated. Similarly, SNS- based discussion with politically agreeing others predicted political participation, whereas discussion with disagreeing people did not contribute to participation. Moreover, attitude-consistent news reception and agreement in political discussion had interactive influences, as the effects of attitude-consistent news on participation become stronger with increases in discussion with agreement. The results suggest that the mobilizing effects of social media mainly work through political agreement rather than disagreement in communication.

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Efficient Call Control Scheme considering Handover Duration Time in Next Generation Mobile Communication Networks (차세대 이동통신망에서 핸드오버 지속시간을 고려한 호 제어 방법)

  • Jang, Heeseon
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2020.07a
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    • pp.555-556
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    • 2020
  • 본 논문에서는 지속적으로 증가하는 이동통신 가입자를 수용하고 초고속 모바일 데이터 서비스를 제공하기 위해서 무선 자원을 효율적으로 사용하기 위한 호 제어 방법을 제안한다. 제안된 방법에서는 핸드오버 호 요구를 효율적으로 처리하고 서비스 품질을 개선하기 위하여 핸드오버 지속시간(핸드오버 요구부터 기존 채널 절단까지의 핸드오버 영역에 머무르는 시간)을 고려하여 핸드오버 영역을 먼저 벗어나는 순서를 예측하고 이를 기준으로 우선순위가 높은 핸드오버 호를 먼저 처리한다. 제안된 방법의 성능을 분석하기 위하여 시뮬레이션을 수행하였으며, 가입자의 새로운 호의 발생 시간 간격과 호의 통화시간을 지수분포로 가정하고 지수분포의 memoryless property 특성을 이용하였다. 수행 결과, 제안된 방법이 기존의 FIFO(First-In-First-Out) 방법에 비하여 호의 블록킹 확률과 강제 종료 확률이 감소(평균 25.2%)됨을 알 수 있다.

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Energy-Based Routing Algorithms in Underwater Multimedia Communication Networks (수중 다중매체 통신 네트워크에서의 에너지 기반 라우팅 알고리즘)

  • Lim, DongHyun;Park, Jaehyeun;Shin, Insik;Kang, Dongmin;Kang, Kyeingmin;Kim, ChangHwa
    • Annual Conference of KIPS
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    • 2021.11a
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    • pp.87-90
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    • 2021
  • 수중 다중매체 통신 또한 수중 통신과 마찬가지로 에너지 확보 문제로 노드의 마비, 높은 에너지 교체 비용등의 문제를 가지고 있다. 이에 본 논문에서는 이전 연구에서 제시된 에너지 소모 산출 모델을 이용하여 수중 다중매체 통신 네트워크를 대상으로 하는 에너지 기반 라우팅 알고리즘을 제시한다.

Variational autoencoder for prosody-based speaker recognition

  • Starlet Ben Alex;Leena Mary
    • ETRI Journal
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    • v.45 no.4
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    • pp.678-689
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    • 2023
  • This paper describes a novel end-to-end deep generative model-based speaker recognition system using prosodic features. The usefulness of variational autoencoders (VAE) in learning the speaker-specific prosody representations for the speaker recognition task is examined herein for the first time. The speech signal is first automatically segmented into syllable-like units using vowel onset points (VOP) and energy valleys. Prosodic features, such as the dynamics of duration, energy, and fundamental frequency (F0), are then extracted at the syllable level and used to train/adapt a speaker-dependent VAE from a universal VAE. The initial comparative studies on VAEs and traditional autoencoders (AE) suggest that the former can efficiently learn speaker representations. Investigations on the impact of gender information in speaker recognition also point out that gender-dependent impostor banks lead to higher accuracies. Finally, the evaluation on the NIST SRE 2010 dataset demonstrates the usefulness of the proposed approach for speaker recognition.