• Title/Summary/Keyword: Asynchronous data

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An Efficient Real Time Processing Method for Frequently Updated Data (빈번한 변경이 요구되는 데이터의 효율적인 실시간 처리 기법)

  • Kim Jin-Deog;Jin Kyo-Hong;Lee Sung-Jin;Jung Hae-Won
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.461-465
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    • 2006
  • Recently, the operator modules to control external devices are concerned about automatic management system to process continuously changed signals. They need a efficient data management with high reliability and real time processing. The characteristics of these data are a large volume, a short report interval and asynchronous report time. The typical queries of these systems consist of the current query to search the latest signal value, the snapshot query to search the signal value of a past time, the historical query to search the signal value of a past tine to current. In this paper, we propose the efficient method to manage the above signals by using a file structured database in QNX operating systems. The data communications among the devices are done by Profibus-FMS protocol and the file databases are used for adjusting monitoring frequency and storing signals. The file database adopts a delta version and a periodical back up in due consideration of the resource limit of a small storage and a low computing power in QNX COM(Cabinet Operator Module).

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A Multi-hop Reservation Method for End-to-End Latency Performance Improvement in Asynchronous MAC-based Wireless Sensor Networks (비동기식 MAC프로토콜 기반의 무선 센서 네트워크에서 단대단 시간 지연 성능 향상을 위한 멀티 홉 예약 기법의 제안)

  • Hong, Sung-Hwa;Jung, Suk-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.7
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    • pp.2638-2647
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    • 2010
  • X-MAC reduces transmission delay and energy consumption by using a short preamble instead of the existing long preamble. To solve the problem of X-MAC, this paper proposes a new MAC protocol called Express-MAC. The wireless sensor network is mainly used for the purpose of gathering event data or situation information. Especially, the transmission pattern of the sensor network with the purpose of event detection such as intrusion detection is very intermittent as well as successively occurring when a single event takes place in most cases. By reflecting sensor network's key transmission patterns as above, EX-MAC has used multi-hub path's path reservation system and awake section's transmission time reservation method in data transmission when the first event takes place. The awake time reservation in transmission path has improved successive data transmission's end-to-end delay, and it has also increased efficiency in terms of energy consumption by reducing the preamble length of data transmission and reception node.

Synchronized Multimedia Technology on Next Generation Web (차세대 웹에서의 멀티미디어 동기화 기술)

  • 신봉희;김성종
    • Journal of Korea Society of Industrial Information Systems
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    • v.4 no.4
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    • pp.60-70
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    • 1999
  • Internet based on web service is growing rapidly and the effort to standardize the next generation web is wold-widely being made. When the web was developed for the first time, HTTP, HTML, and URL were designed based on the structure of text background. Through those asynchronous search and simple unified expression patterns have been used But recently many data on internet me becoming complicated Consequently new structure and expression patterns including synchronous multimedia information are requested The currently used standard language among user interface domain of W3C is SMIL which is XML-based one SMIL describes where and how long the multimedia factors are integrated on the web. In this paper the standardization trend and important issues related to SMIL are reviewed and analysed Also the development of technology is discussed.

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MicroPost: The Design of an Efficient Event Notification Architecture for Distributed Social Applications (MicroPost: 분산형 소셜 애플리케이션을 위한 효율적인 이벤트 통지 아키텍처의 설계)

  • Bae, Joon-Hyun;Kim, Sang-Wook
    • 한국HCI학회:학술대회논문집
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    • 2009.02a
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    • pp.232-239
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    • 2009
  • Emerging social networking services provide a new paradigm for human-to-human communication. However, these services are centralized and managed by single service provider. In this paper, we propose MicroPost, a decentralized event notification service architecture for social applications based on publish/subscribe model. In our design space, event brokers are structured as an overlay network which provides the substrate of distributed peer-to-peer lookup service for storing and retrieving subscriptions with hashed keys. Event clients interact with event brokers to publish or subscribe social messages over the wide-area network. Using XML standards, we present an efficient algorithm to forward events for rendezvous-based matching in this paper. In our design space, the cost of routing is O(${\omega}log_kN$), where N is the number of event brokers, ${\omega}$ is the number of meta-data obtained from event messages, and k is a constant, which is selected by our design, to divide the identifier space and to conquer the lookup of given key. Consequently, what we achieved is an asynchronous social messaging service architecture which is decentralized, efficient, scalable, and flexible.

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A Study on the Knowledge Measurement md Sharing Methodology at the Knowledge-Oriented Organization (지식지향적 조직에 있어서의 지식평가 및 공유방법에 관한 연구)

  • 이상근;유상진;장영택
    • Journal of Korea Society of Industrial Information Systems
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    • v.6 no.3
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    • pp.1-19
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    • 2001
  • Internet based on web service is growing rapidly and the effort to standardize the next generation web is world-widely being made. When the web was developed for the first time, HTTP, HTML, and URL were designed based on the structure of text background. Through those, asynchronous search and simple, unified expression patterns have been used. But recently many data on internet are becoming complicated. Consequently new structure and expression patterns including synchronous multimedia information are requested. The currently used standard language among user interface domain of W3C is SMIL which is XML-based one. SMIL describes where and how long the multimedia factors are integrated on the web. In this paper the standardization trend and important issues related to SMIL are reviewed and analyzed. Also the development of technology is discussed.

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Distributed Multicast Routing Algorithm for Non-Interactive Video/Audio Distribution (비상호적 비디오/오디오 분배를 위한 분산형 멀티캐스트 라우팅 알고리즘)

  • Yi, Yung;Lee, Young-Seok;Choi, Yang-Hee
    • Journal of KIISE:Information Networking
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    • v.28 no.4
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    • pp.508-516
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    • 2001
  • This paper proposes multicast routing algorithm that operates for non-interactive multimedia applications such as VOD(Video On Demand) and real-time data broadcasting. It is possible that there exist multiple senders in non-interactive multimedia applications. This paper designs multicast routing algorithm in this environment. The simulation of algorithm proposed in this paper shows much better performancetcost, delay) than that of only one source. To guarantee the performance of algorithm, Broadband ATM network is modelled in simulation.

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Sexual Maturity and Spawning of Ocean Sunfish Mola mola in Korean Waters (한국 근해 개복치(Mola mola)의 성숙과 산란)

  • Kang, Min Joo;Baek, Hea Ja;Lee, Dong Woo;Choi, Jung Hwa
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.5
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    • pp.739-744
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    • 2015
  • The sexual maturation and spawning time of female ocean sunfish Mola mola in Korean waters were studied by observing the gonads histologically. Specimens were purchased in a fish market in October 2013 and May, June, and October 2014. Nine females (total length 100-250 cm, gonad weight 31-3,470 g) and one male (total length 131 cm, gonad weight 60 g) were studied. Histologically, the ovaries became active in May and spawning began in July and continued until October. In July, mature oocytes and yolk globule stage oocytes were observed; parts of the gonad showed traces of spawning, while others had degenerated and absorbed any oocytes. By October, many oocytes had degenerated and been absorbed. Therefore, the approximate spawning period of ocean sunfish is from July to October based on histological changes in the gonads. The asynchronous oocyte development suggests that the ocean sunfish is a multiple spawner, as reported previously. The catch distribution data suggest that the waters around Jeju Island are a sunfish spawning area.

A Fully Synthesizable Bluetooth Baseband Module for a System-on-a-Chip

  • Chun, Ik-Jae;Kim, Bo-Gwan;Park, In-Cheol
    • ETRI Journal
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    • v.25 no.5
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    • pp.328-336
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    • 2003
  • Bluetooth is a specification for short-range wireless communication using the 2.4 GHz ISM band. It emphasizes low complexity, low power, and low cost. This paper describes an area-efficient digital baseband module for wireless technology. For area-efficiency, we carefully consider hardware and software partitioning. We implement complex control tasks of the Bluetooth baseband layer protocols in software running on an embedded microcontroller. Hardware-efficient functions, such as low-level bitstream link control; host controller interfaces (HCIs), such as universal asynchronous receiver transmitter (UART) and universal serial bus (USB)interfaces; and audio Codec are performed by dedicated hardware blocks. Furthermore, we eliminate FIFOs for data buffering between hardware functional units. The design is done using fully synthesizable Verilog HDL to enhance the portability between process technologies so that our module can be easily integrated as an intellectual property core no system-on-a-chip (SoC) ASICs. A field programmable gate array (FPGA) prototype of this module was tested for functional verification and realtime operation of file and bitstream transfers between PCs. The module was fabricated in a $0.25-{\mu}m$ CMOS technology, the core size of which was only 2.79 $mm{\times}2.80mm$.

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Asynchronous Cache Consistency Technique (비동기적 캐쉬 일관성 유지 기법)

  • 이찬섭
    • Journal of the Korea Society of Computer and Information
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    • v.9 no.2
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    • pp.33-40
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    • 2004
  • According as client/server is generalized by development of computer performance and information communication technology, Servers uses local cache for extensibility and early response time, and reduction of limited bandwidth. Consistency of cached data need between server and client this time and much technique are proposed according to this. This Paper improved update frequency cache consistency in old. Existent consistency techniques is disadvantage that response time is late because synchronous declaration or abort step increases because delaying write intention declaration. Techniques that is proposed in this paper did to perform referring update time about object that page request or when complete update operation happens to solve these problem. Therefore, have advantage that response is fast because could run write intention declaration or update by sel_mode electively asynchronously when update operation consists and abort step decreases and clearer selection.

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Some Aspects of Laying, Incubation and Hatching in the Great Reed-Warbler

  • Yoo, Jeong-Chil;Park, Yu-Seong
    • 한국생태학회:학술대회논문집
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    • 2002.08a
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    • pp.107-111
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    • 2002
  • During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations In overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggest- ing the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The average number of days of hatching asynchrony was 2.5, raging 0.5∼2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

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