• Title/Summary/Keyword: Query Command

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Power consumption estimation of active RFID system using simulation (시뮬레이션을 이용한 능동형 RFID 시스템의 소비 전력 예측)

  • Lee, Moon-Hyoung;Lee, Hyun-Kyo;Lim, Kyoung-Hee;Lee, Kang-Won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.8
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    • pp.1569-1580
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    • 2016
  • For the 2.4 GHz active RFID to be successful in the market, one of the requirements is the increased battery life. However, currently we do not have any accurate power consumption estimation method. In this study we develop a simulation model, which can be used to estimate power consumption of tag accurately. Six different simulation models are proposed depending on collision algorithm and query command method. To improve estimation accuracy, we classify tag operating modes as the wake-up receive, UHF receive, sleep timer, tag response, and sleep modes. Power consumption and operating time are identified according to the tag operating mode. Query command for simplifying collection and ack command procedure and newly developed collision control algorithm are used in the simulation. Other performance measures such as throughput, recognition time for multi-tags, tag recognition rate including power consumption are compared with those from the current standard ISO/IEC 18000-7.

A Scheme for Guaranteeing Fair Identification Delay in Gen-2 RFID Systems

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • v.9 no.1
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    • pp.44-49
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    • 2011
  • In RFID System, when multiple tags respond simultaneously, a collision can occur. A method that solves this collision is referred to anti-collision algorithm. In Gen-2 RFID system, if the slot-count size varies during a query round due to the collisions, a new query round begins with a QueryAdjust command. Anti-collision algorithm of Gen-2 RFID system is simple. But, it has the tag starvation problem that a tag may never be successfully identified because its responses always collide with others. Therefore, this paper proposes a scheme to guarantee the fair identification delay. In the proposed scheme, if the slot-count value changes due to the collisions, the reader broadcasts a CollisionRound command to begin a collision round. During the collision round, the reader identifies only tags that occurred collision during the previous query round.

Implementation of query model of CQRS pattern using weather data (기상 데이터를 활용한 CQRS 패턴의 조회 모델 구현)

  • Seo, Bomin;Jeon, Cheolho;Jeon, Hyeonsig;An, Seyun;Park, Hyun-ju
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.6
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    • pp.645-651
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    • 2019
  • At a time when large amounts of data are being poured out, there are many changes in software architecture or data storage patterns because of the nature of the data being written, rather more read-intensive than writing. Accordingly, in this paper, the query model of Command Query Responsibility Segmentation (CQRS) pattern separating the responsibilities of commands and queries is used to implement an efficient high-capacity data lookup system in users' requirements. This paper uses the 2018 temperature, humidity and precipitation data of the Korea Meteorological Administration Open API to store about 2.3 billion data suitable for RDBMS (PostgreSQL) and NoSQL (MongoDB). It also compares and analyzes the performance of systems with CQRS pattern applied from the perspective of the web server (Web Server) implemented and systems without CQRS pattern, the storage structure performance of each database, and the performance corresponding to the data processing characteristics.

Anti-collision Algorithm with Early Cancellation of Query Round in RFID Systems

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • v.7 no.3
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    • pp.292-296
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    • 2009
  • The performance of anti-collision algorithm in RFID systems, which are based on FSA algorithm, may be affected by the frame size a query round. In this paper, an anti-collision algorithm with early cancellation of query round is proposed to enhance the performance of EPCglobal Class-1 Gen-2. The Q-algorithm calculates a Q value to determine the next frame size during a query round. In the proposed algorithm, if the new Q value is different from the previous one, the reader transmits a QueryAdjust command to cancel the current query round. The simulation results show that the proposed algorithm can have a stable performance irrespective of the C value of Q-algorithm and the number of tags.

Study on the Performance Improvement of Active RFID System (능동형 RFID 시스템의 성능 향상을 위한 연구)

  • Kim, Ji-Tae;Kim, Jin-Sung;Lee, Kang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.5
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    • pp.871-885
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    • 2015
  • The improved DFSA for 2.4GHz multi-tags active RFID is suggested in 2 different ways: 1) simplified tag collection and Ack procedure using query command and 2) modified Schoute's method to control the number of slots in the frame. To evaluate the performance of the improved system we develop the simulation model. Varying the number of tags in the system we track the performance measures such as throughput, recognition time for multi-tags and tag recognition rate during a given time. The suggested method shows the best performance over all measures. Simplification of collection and Ack commands using query commands contributes to reducing tag recognition time. And the modified Schoute's method which controls the frame size using $k_1$ and $k_2$ contributes to throughput improvement and reduces target cognition time by reducing the number of collection rounds.

Tag Anti-Collision Algorithms in Passive and Semi-passive RFID Systems -Part I : Adjustable Framed Q Algorithm and Grouping Method by using QueryAdjust Command- (수동형/반능동형 RFID 시스템의 태그 충돌 방지 알고리즘 -Part I : QueryAdjust 명령어를 이용한 AFQ 알고리즘과 Grouping에 의한 성능개선-)

  • Song, In-Chan;Fan, Xiao;Chang, Kyung-Hi;Shin, Dong-Beom;Lee, Heyung-Sub
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.8A
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    • pp.794-804
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    • 2008
  • In this paper, we analyze the performance of probabilistic slotted anti-collision algorithm used in EPCglobal Class-1 Generation-2 (Gen2). To increase throughput and system efficiency, and to decrease tag identification time and collision ratio, we propose new tag anti-collision algorithms, which are FAFQ (fired adjustable flamed Q) algorithm and AAFQ (adaptive adjustable framed Q) algorithm, by using QueryAdjust command. We also propose grouping method based on Gen2 to improve the efficiency of tag identification. The simulation results show that all the proposed algorithms outperform Q algorithm, and AAFQ algorithm performs the best. That is, AAFQ has an increment of 5% of system efficiency and a decrement of 4.5% of collision ratio. For FAFQ and AAFQ algorithm, the performance of grouping method is similar to that of ungrouping method. However, for Q algorithm in Gen2, grouping method can increase throughput and system efficiency, and decrease tag identification time and collision ratio compared with ungrouping method.

Efficient Fine-grained Log Auditing using Correlation Method based on Secure OS (Secure OS 기반에서 상호연관 기법을 통한 효과적 상세 로그 감사)

  • Koo, Ha-Sung;Park, Tae-Kyou
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.11
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    • pp.2381-2390
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    • 2011
  • This paper presents the effective and detailed secure monitoring method being used based on Secure OS. For this, the detailed secure log of process, object, user's command and database query in task server are collected by 3 kinds of log collecting module. The log collecting modules are developed by ourselves and contained as constituents of security system. Secure OS module collects process and system secure log of objective unit, Backtracker module collects user's command session log, SQLtracker module collects database query in details. When a system auditor monitors and traces the behaviour of specified user or individual user, the mutual connection method between the secure logs can support detailed auditing and monitering effectively.

A Study of Command & Control Server through Analysis - DNS query log (명령제어서버 탐색 방법 - DNS 분석 중심으로)

  • Cheon, Yang-Ha
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.12
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    • pp.1849-1856
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    • 2013
  • DOS attack, the short of Denial of Service attack is an internet intrusion technique which harasses service availability of legitimate users. To respond the DDoS attack, a lot of methods focusing attack source, target and intermediate network, have been proposed, but there have not been a clear solution. In this paper, we purpose the prevention of malicious activity and early detection of DDoS attack by detecting and removing the activity of botnets, or other malicious codes. For the purpose, the proposed method monitors the network traffic, especially DSN traffic, which is originated from botnets or malicious codes.

Design of A IoT Platform Based on CQRS Pattern to Accommodate Various Requirements and Improve Data Query Performance (다양한 요구사항 수용 및 데이터 조회 성능 향상을 위한 CQRS 패턴 기반의 사물인터넷 플랫폼 설계)

  • Jeon, Cheol-Ho;Jeon, Hyeon-Sig;Park, Hyun-Ju
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.11
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    • pp.1539-1545
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    • 2020
  • With the advent of the ubiquitous era due to the development of science and technology in the modern society, interest in data generated in the IoT environment has increased socially. However, the existing IoT platform has difficulties in processing inquiry requests that require large amounts of throughput, such as statistical processing of large amounts of data. Accordingly, in this paper, we propose an IoT platform that can flexibly accommodate requirements for inquiry requests and improve inquiry performance. The platform proposed in this paper showed a performance improvement of about 1200 times in terms of average response time by introducing a separate read database. By separating the object model into a command side and a query side, the complexity of the object is reduced to meet the various demands on the platform. It was made to allow quick acceptance of the matter.

A Novel Approach for Accessing Semantic Data by Translating RESTful/JSON Commands into SPARQL Messages

  • Nguyen, Khiem Minh;Nguyen, Hai Thanh;Huynh, Hiep Xuan
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.3
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    • pp.222-229
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    • 2016
  • Linked Data is a powerful technology for storing and publishing the structures of data. It is helpful for web applications because of its usefulness through semantic query data. However, using Linked Data is not easy for ordinary users who lack knowledge about the structure of data or the query syntax of Linked Data. For that problem, we propose a translator component that is used for translating RESTful/JSON request messages into SPARQL commands based on ontology - a metadata that describes the structure of data. Clients do not need to worry about the structure of stored data or SPARQL, a kind of query language used for querying linked data that not many people know, when they insert a new instance or query for all instances of any specific class with those complex structure data. In addition, the translator component has the search function that can find a set of data from multiple classes based on finding the shortest paths between the target classes - the original set that user provide, and target classes- the users want to get. This translator component will be applied for any dynamic ontological structure as well as automatically generate a SPARQL command based on users' request message.