• Title/Summary/Keyword: Synchronization protocol

Search Result 259, Processing Time 0.023 seconds

A Study for the Development of Neurofeedback Biosignal Index for Tic Response Supression Test of Tourette's Syndrome (투렛증후군의 틱 반응 억제 시험을 통한 뉴로피드백 생체신호 지표 개발 시론)

  • Woo, Jeong-Gueon;Kim, Wuon-Sik
    • The Journal of the Korea Contents Association
    • /
    • v.22 no.10
    • /
    • pp.861-869
    • /
    • 2022
  • In patients with Tourette's syndrome, a tic occurs when Mu wave synchronization is broken. Conversely, when Mu wave synchronization is achieved, a tick does not occur. When the tic is suppressed, the cognitive control response process is changed, and if the neurofeedback training that adjusts the EEG frequency power is performed with the changed, the patient will be treated autonomously without artificially suppressing the tic. The results of the research test suggest that if the tic patient does not artificially synchronize mu waves in the premotor cortex (Frontal Cortical 3 site), and if EEG control is performed autonomously like neurofeedback training, as a result, tics do not occur. Cognitive control response processes are altered when a subject is inhibited from tics. By training the altered cognitive control with neurofeedback that modulates EEG frequency power, the patient can be treated autonomously without artificially suppressing the tic.Mu-wave synchronizationcan now be added to existing neurofeedback treatment protocols such as SMR reinforcement, theta-beta-wave imbalance correction, and alpha-wave reinforcement. This study will be used in follow-up studies and clinical trials to more scientifically verify the neurofeedback treatment protocol, a treatment for patients with Tourette's syndrome.

An adaptive keystream resynchronization algorithm by using address field of LAPB (LAPB의 주소 영역을 이용한 적응 난수열 재동기 알고리즘)

  • 윤장홍;이주형;황찬식;양상운
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.22 no.10
    • /
    • pp.2181-2190
    • /
    • 1997
  • The synchronous stream cipher has the problem of synchronization loss by cycle slip. Synchronization loss make the state which sender and receiver can't communicate and it may make the receiving system disordered. To lessen the risk, we usually use a continuous resynchronization which achieve resynchronization at fixed timesteps by inserting synchronization pattern and session key. While we can get effectively resynchronizationby continuous resynchronization, there are some problems. In this paper, we proposed an adaptive resynchronization algorithm for cipher system using LAPB protocol. It is able to solve the problem of the continunous resynchronization.The proposed adaptive algorithm make resynchronization only in the case that the resynchronization is occurred by analyzing the address field of LAPB. It measure the receiving rate of the address field in the decesion duration. If the receiving rate is smaller than threshold value, it make resynchronization or not. By using adaptively resynchronization, it solves the problems of continunous resynchronization. When the proposed adaptive algorithm is applied to the synchronous stream cipher system which is used in X.25 packet network, it reduced the time for resynchronization by ten times. It means that 11.3% of total data for transmit is compressed.

  • PDF

Reliable multi-hop communication for structural health monitoring

  • Nagayama, Tomonori;Moinzadeh, Parya;Mechitov, Kirill;Ushita, Mitsushi;Makihata, Noritoshi;Ieiri, Masataka;Agha, Gul;Spencer, Billie F. Jr.;Fujino, Yozo;Seo, Ju-Won
    • Smart Structures and Systems
    • /
    • v.6 no.5_6
    • /
    • pp.481-504
    • /
    • 2010
  • Wireless smart sensor networks (WSSNs) have been proposed by a number of researchers to evaluate the current condition of civil infrastructure, offering improved understanding of dynamic response through dense instrumentation. As focus moves from laboratory testing to full-scale implementation, the need for multi-hop communication to address issues associated with the large size of civil infrastructure and their limited radio power has become apparent. Multi-hop communication protocols allow sensors to cooperate to reliably deliver data between nodes outside of direct communication range. However, application specific requirements, such as high sampling rates, vast amounts of data to be collected, precise internodal synchronization, and reliable communication, are quite challenging to achieve with generic multi-hop communication protocols. This paper proposes two complementary reliable multi-hop communication solutions for monitoring of civil infrastructure. In the first approach, termed herein General Purpose Multi-hop (GPMH), the wide variety of communication patterns involved in structural health monitoring, particularly in decentralized implementations, are acknowledged to develop a flexible and adaptable any-to-any communication protocol. In the second approach, termed herein Single-Sink Multi-hop (SSMH), an efficient many-to-one protocol utilizing all available RF channels is designed to minimize the time required to collect the large amounts of data generated by dense arrays of sensor nodes. Both protocols adopt the Ad-hoc On-demand Distance Vector (AODV) routing protocol, which provides any-to-any routing and multi-cast capability, and supports a broad range of communication patterns. The proposed implementations refine the routing metric by considering the stability of links, exclude functionality unnecessary in mostly-static WSSNs, and integrate a reliable communication layer with the AODV protocol. These customizations have resulted in robust realizations of multi-hop reliable communication that meet the demands of structural health monitoring.

A Robust Biometric-based User Authentication Protocol in Wireless Sensor Network Environment (무선센서네트워크 환경에서 생체기반의 개선된 사용자 인증 프로토콜)

  • Shin, Kwang-Cheul
    • The Journal of Society for e-Business Studies
    • /
    • v.18 no.3
    • /
    • pp.107-123
    • /
    • 2013
  • In a wireless sensor network environment, it is required to ensure anonymity by keeping sensor nodes' identifiers not being revealed and to support real-time authentication, lightweight authentication and synchronization. In particular, there exist possibilities of location information leakage by others, privacy interference and security vulnerability when it comes to wireless telecommunications. Anonymity has been an importance issue in wired and wireless network environment, so that it has been studied in wide range. The sensor nodes are interconnected among them based on wireless network. In terms of the sensor node, the researchers have been emphasizing on its calculating performance limit, storage device limit, and smaller power source. To improve of biometric-based D. He scheme, this study proposes a real-time authentication protocol using Unique Random Sequence Code(URSC) and variable identifier for enhancing network performance and retaining anonymity provision.

Encryption Communication Protocol Design Using Unidirectional Synchronization of the Chaos System (혼돈계의 단방향 동기화를 이용한 보안 프로토콜 설계)

  • Cho, Chang-Ho;Yim, Geo-Su
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.9 no.10
    • /
    • pp.1125-1130
    • /
    • 2014
  • The quantity and quality of contents containing information are sharply increasing with the rising network speed. In line with this rapid growth of information volume, a new communication protocol using the chaotic signal that can protect contents in communication is proposed as follows. The chaos system has the characteristic of unpredictability due to the sensitive initial values and the similarity of the signals with noise. We configured two chaos systems $F(X_n,Y_n)$ and $G(A_n,B_n)$ that have such characteristics and designed a data communication method using as encryption channel the same chaos signals generated by synchronizing the chaos system G with the F signals. The proposed method was verified with the encryption and decryption of images. The proposed method is different from the existing encrypted communication methods and is expected to lay the foundation for future studies in related areas.is an example of ABSTRACT format.

Efficient Hardware Support: The Lock Mechanism without Retry (하드웨어 지원의 재시도 없는 잠금기법)

  • Kim Mee-Kyung;Hong Chul-Eui
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.10 no.9
    • /
    • pp.1582-1589
    • /
    • 2006
  • A lock mechanism is essential for synchronization on the multiprocessor systems. The conventional queuing lock has two bus traffics that are the initial and retry of the lock-read. %is paper proposes the new locking protocol, called WPV (Waiting Processor Variable) lock mechanism, which has only one lock-read bus traffic command. The WPV mechanism accesses the shared data in the initial lock-read phase that is held in the pipelined protocol until the shared data is transferred. The nv mechanism also uses the cache state lock mechanism to reduce the locking overhead and guarantees the FIFO lock operations in the multiple lock contentions. In this paper, we also derive the analytical model of WPV lock mechanism as well as conventional memory and cache queuing lock mechanisms. The simulation results on the WPV lock mechanism show that about 50% of access time is reduced comparing with the conventional queuing lock mechanism.

Speech Quality Measure for VoIP Using Wavelet Based Bark Coherence Function (웨이블렛 기반 바크 코히어런스 함수를 이용한 VoIP 음질평가)

  • 박상욱;박영철;윤대희
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.27 no.4A
    • /
    • pp.310-315
    • /
    • 2002
  • The Bark Coherence Function (BCF) defies a coherence function within perceptual domain as a new cognition module, robust to linear distortions due to the analog interface of digital mobile system. Our previous experiments have shown the superiority of BCF over current measures. In this paper, a new BCF suitable for VoIP is developed. The unproved BCF is based on the wavelet series expansion that provides good frequency resolution while keeping good time locality. The proposed Wavelet based Bark Coherence function (WBCF) is robust to variable delay often observed in packet-based telephony such as Voice over Internet Protocol (VoIP). We also show that the refinement of time synchronization after signal decomposition can improve the performance of the WBCF. The regression analysis was performed with VoIP speech data. The correlation coefficients and the standard error of estimates computed using the WBCF showed noticeable improvement over the Perceptual Speech Quality Measure (PSQM) that is recommended by ITU-T.

A Mobile P2P Semantic Information Retrieval System with Effective Updates

  • Liu, Chuan-Ming;Chen, Cheng-Hsien;Chen, Yen-Lin;Wang, Jeng-Haur
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.9 no.5
    • /
    • pp.1807-1824
    • /
    • 2015
  • As the technologies advance, mobile peer-to-peer (MP2P) networks or systems become one of the major ways to share resources and information. On such a system, the information retrieval (IR), including the development of scalable infrastructures for indexing, becomes more complicated due to a huge increase on the amount of information and rapid information change. To keep the systems on MP2P networks more reliable and consistent, the index structures need to be updated frequently. For a semantic IR system, the index structure is even more complicated than a classic IR system and generally has higher update cost. The most well-known indexing technique used in semantic IR systems is Latent Semantic Indexing (LSI), of which the index structure is generated by singular value decomposition (SVD). Although LSI performs well, updating the index structure is not easy and time consuming. In an MP2P environment, which is fully distributed and dynamic, the update becomes more challenging. In this work, we consider how to update the sematic index generated by LSI and keep the index consistent in the whole MP2P network. The proposed Concept Space Update (CSU) protocol, based on distributed 2-Phase locking strategy, can effectively achieve the objectives in terms of two measurements: coverage speed and update cost. Using the proposed effective synchronization mechanism with the efficient updates on the SVD, re-computing the whole index on the P2P overlay can be avoided and the consistency can be achieved. Simulated experiments are also performed to validate our analysis on the proposed CSU protocol. The experimental results indicate that CSU is effective on updating the concept space with LSI/SVD index structure in MP2P semantic IR systems.

Spatio-temporal Query Processing Systems for Ubiquitous Environments (유비쿼터스 환경을 위한 시공간 질의 처리 시스템)

  • Lee, Ki-Young;Lim, Myung-Jae;Kim, Kyu-Ho;Kim, Joung-Joon
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.10 no.3
    • /
    • pp.145-152
    • /
    • 2010
  • With the recent development of the ubiquitous computing technology, there are increasing interest and research in technologies such as sensors and RFID related to information recognition and location positioning in various ubiquitous fields. Especially, RTLS(Real-Time Locating Services) dealing with spatio-temporal data is emerging as a promising technology. For these reasons, the ISO/IEC published the RTLS standard specification for compatibility and interoperability in RTLS. Therefore, in this paper, we designed and implemented Spatio-temporal Query Processing Systems for efficiently managing and searching the incoming Spatio-temporal data stream of moving objects. Spatio-temporal Query Processing Systems's spatio-temporal middleware maintains interoperability among heterogeneous devices and guarantees data integrity in query processing through real time processing of unceasing spatio-temporal data streams and two way synchronization of spatio-temporal DBMSs. Web Server uses the SOAP(Simple Object Access Protocol) message between client and server for interoperability and translates client's SOAP message into CQL(Continuous Query Language) of the spatio-temporal middleware. Finally, this thesis proved the utility of the system by applying the spatio-temporal Query Processing Systems to a real-time Locating Services.

Implementation of a FLEX Protocol Signal Processor for High Speed Paging System (고속 페이징 시스템을 위한 FLEX 프로토콜 신호처리기의 구현)

  • Gang, Min-Seop;Lee, Tae-Eung
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.38 no.1
    • /
    • pp.69-78
    • /
    • 2001
  • This paper presents the design and FPGA implementation of a FLEX PSP(Protocol Signal Processor) for the portable high speed paging system. In this approach, two algorithms are newly proposed for implementing the PSP which provides capabilities of the maximum 6,400bps at speed, high-channel throughput, real time error correction and an effective frame search function. One is an accurate symbol synchronization algorithm which is applied for synchronizing the interleaved 4-level bit symbols which are received at input stage of A/D converter, and the other is a modified fast decoding algorithm which is provided for realizing double error correction of (31,21)BCH signal. The PSP is composed of six functional modules, and each module is modelled in VHDL(VHSIC Hardware Description Language). Both functional simulation and logic synthesis have performed for the proposed PSP through the use of Synopsys$^{TM}$ tools on a Axil-320 Workstation, and where Altera 10K libraries are used for logic synthesis. From logic synthesis, we can see that the number of gates is about 2,631. For FPGA implementation, timing simulation is performed by using Altera MAX+ PLUS II, and its results will be also given. The PSP which is implemented in 6 FPGA devices on a PCB has been verified by means of Logic Analyzer.r.

  • PDF