• Title/Summary/Keyword: 병행제어

Search Result 216, Processing Time 0.026 seconds

A Concurrency Control Technique Using Optimistic Atomic Broadcast In Replicated Database Systems (중복 데이터베이스 시스템에서 낙관적인 원자적 방송을 이용한 동시성제어 기법)

  • Choe, Hui-Yeong;Hwang, Bu-Hyeon
    • The KIPS Transactions:PartD
    • /
    • v.8D no.5
    • /
    • pp.543-552
    • /
    • 2001
  • To process transactions in fully replicated database, an atomic broadcast is mainly used. In this case of using atomic broadcast, transactions can be delayed because of the coordinating step among servers before processing the transaction. In this paper, we propose an algorithm to resolve the problem of transaction delay. In the proposed algorithm, the transactions are processed by using the optimistic method. The operations of a transaction are performed in the site that it is submitted and its write operations its updates atomically in all replicated sites. Since the serializability of transaction is ensured by checking the sequence number of transactions in the completion-inspection step.

  • PDF

Personalized Media Control Method using Probabilistic Fuzzy Rule-based Learning (확률적 퍼지 룰 기반 학습에 의한 개인화된 미디어 제어 방법)

  • Lee, Hyeong-Uk;Kim, Yong-Hwi;Lee, Tae-Yeop;Park, Gwang-Hyeon;Kim, Yong-Su;Jo, Jun-Myeon;Byeon, Jeung-Nam
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2006.11a
    • /
    • pp.25-28
    • /
    • 2006
  • 사용자 의도 파악 (intention reading) 기술은 스마트 홈과 같은 복잡한 유비쿼터스(ubiquitous) 환경에서 사용자에게 보다 편리하고 개인화된(personalized) 서비스 제공이 가능하도록 해준다. 또한 학습 기능(learning capability)은 지식 발견(knowledge discovery)의 관점에서 의도 파악 기술의 핵심 요소 기술의 하나로 자리 매김 하고 있다. 본 논문에서는 스마트 홈 환경에서 제공 가능한 개인화된 서버스(personalized service) 중의 하나로, 개인화된 미디어 제어 방법에 대한 내용을 다룬다. 특히, 이러한 사람의 행동 패턴과 같은 데이터는 패턴 분류의 관점에서 구분해야 할 클래스(class)에 비해 입력 정보가 불충분할 경우가 많으므로 비일관적인(inconsistent) 데이터가 많으므로, 퍼지 논리(fuzzy logic)와 확률(probability)의 개념을 효과적으로 병행해야 의미 있는 지식을 추출해 낼 수 있다. 이를 위하여 반복 퍼지 지도 클러스터링 (IFCS; Iterative Fuzzy Clustering with Supervision) 알고리즘에 기반하여 주어진 데이터 패턴으로부터 확률적 퍼지 룰(probabilistic fuzzy rule)을 얻어 내는 방법에 대해 설명한다. 또한 이를 포함하는 학습 제어 시스템을 통해 개인화된 미디어 서비스를 추천해 줄 수 있는 방법에 대해서 설명하도록 한다.

  • PDF

Intelligent Controller for Constant Control of Residual Chlorine in Water Treatment Process (정수장 잔류염소 일정제어를 위한 지능형 제어기 개발)

  • Lee, Ho-Hyun;Jang, Sang-Bok;Hong, Sung-Taek;Chun, Myung-Geun
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.24 no.2
    • /
    • pp.147-154
    • /
    • 2014
  • In this study, chlorine modeling technique based on fuzzy system is proposed to reduce the carcinogenic substance and decide the optimal chlorine injection rate, which is affected by chlorine evaporation rate in sedimentation basin according to detention time, weather and water quality. The additional chlorine meter is installed in the inlet part of sedimentation to reduce the feedback time and implement cascade control, which leads to maintaining the residual chlorine concentration decided by fuzzy rule. It helps to take a preemptive action about long time delay, the characteristics of the disinfection process, and reduce the variation of residual chlorine rate by 7.3 times and the chlorine consumption by 40,000 dollars. It made a significant contribution to supply hygienically safe drinking water.

A Concurrency Control Method for Data Broadcasting in Mobile Computing Environment (이동 컴퓨팅 환경에서 데이타 방송을 위한 동시성 제어 기법)

  • 윤혜숙;김영국
    • Journal of KIISE:Databases
    • /
    • v.31 no.2
    • /
    • pp.140-149
    • /
    • 2004
  • Data broadcast has received much attention as a very efficient method for disseminating data items in mobile environment with large number of mobile clients. In this approach, a database server periodically and continuously broadcasts data items through wireless channels and clients perform read-only transactions by accessing necessary data items from the air. While broadcasting, the server must also process update transactions on the database, which raises an obstacle for client's accessing consistent data. In this research, we propose a new algorithm SCDSC(Serialization Checking with DirtySet on Commit) which is an alternative for solving the concurrency control problem efficiently. The SCDSC is a kind of optimistic concurrency control in that a client checks the consistency of data using a DirtySet as a part of data broadcast when it commits its transaction. In each broadcast cycle, the server updates and disseminates the DirtySet with newly changed data items for last few cycles in the sliding window approach. We perform an analysis and a simulation study to evaluate the performance of our SCDSC algorithm in terms of data consistency and data currency.

A Study on the Optimal Control Algorithms for the Advanced Wastewater Treatment Process with Variable Hydrodynamic Flow Patterns (유로 변경식 고도하수처리 공정의 최적 제어 알고리즘에 관한 연구)

  • Kang, Seong-Wook;Cho, Wook-Sang;Huh, Hyung-Woo
    • Applied Chemistry for Engineering
    • /
    • v.16 no.2
    • /
    • pp.217-225
    • /
    • 2005
  • Because of the limitation of controllable operation variables for the wastewater treatment process with variable hydrodynamic flow patterns, it may preclude the use of this type of nutrient removal activated sludge process. As the operation variables, only temperature and dissolved oxygen (DO) have been used to operate the process. This study made an effort to improve treatment efficiency and operability of the process by the following methodologies: 1) process and operation data analysis using process simulation, 2) determination of optimal control logic or algorithm using a pilot-scaled experimental apparatus and its operations, and 3) application of experimental and simulation results to find the optimal process operation modes. In this study, it was found that the optimal operation mode named 'save mode' in the basis of process variables, such as the ammonia-nitrogen concentration of inlet flow, temperature and flow rate, can reduce the operation cost comparing with the present normal operation mode. And the stable conditions in nitrification were also shown by the proportional control of DO with the inlet air flow rate of blower and the mixing rate of mechanical aeration.

Radiation Therapy in Carcinoma of the Vulva A Review of Fifteen Patients (외음부 암의 방사선 치료)

  • Lee H. S.;Oh W. Y.;Suh C. O.;Kim G. E.;Park C. K.
    • Radiation Oncology Journal
    • /
    • v.3 no.1
    • /
    • pp.51-58
    • /
    • 1985
  • This study analyzes fifteen patients who underwent a course of radiation therpy for their vulva cancer in the Department of Radiation Oncology, College of Medicine, Yonsei University from January, 1971 to April, 1985. Four patients had initial surgery for their vulva cancer and were subsequently treated by a course of adjuvant radiation therapy. Eleven patients were given radiation therapy as the initial course of therapy, and one of these was in adjuvant setting before radical surgery. Treatment in each instance was individuilzed and usually consisted of some components of external beam, brachytherapy, and/or electron beam therapy. Primary local control rate in all cases was $53\%(8/15),\;40\%(4/10)$ in the radiation therapy alone group and $80\%(4/5)$ in the radiation therapy combined with surgery group. Treatment failures were noted in 7/10 in the radiation therapy alone group and 2/5 in the radiation therapy combined with surgery group. The most common failure site was primary site failure(vulva).

  • PDF

Approaches to Internal Corrosion Control Technologies by Controlling Water Quality in Water Treatment Systems (수질제어를 통한 관 내부 부식방지 기술의 정수처리공정 적용방안)

  • Seo, Dae-Keun;Wang, Chang-Keun
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.20 no.4
    • /
    • pp.509-518
    • /
    • 2006
  • Although final water of domestic water treatment plants almost contains highly corrosive characteristics, the countermeasures for eliminating internal corrosion of pipeline system have not been conducted yet by controlling water quality in plants. The technologies of internal corrosion control are to control water quality parameters(pH, Alkalinity, and Calcium Hardness etc.) and to use corrosion inhibitor. Under the conditions of domestic water treatment, first of all, the technologies of adjusting water quality parameters has to be considered. Otherwise, The technology of using corrosion inhibitor is favorably thought to be applied with the technology of adjusting water quality parameters in accordance with the result of availability for water treatment process. Since the technology of adjusting water quality parameter influences on other water treatment processes, the guideline of water quality management to be apt for water quality characteristic is required to be estabilished. While the selection of proper chemicals and technologies is dependent upon the raw water characteristics and water treatment process, typically, the technology of $Ca(OH)_2$ & $CO_2$ additions is considered more effective than other technologies in order to adjust pH and Alkalinity, increase $Ca^{2+}$ and form $CaCO_3$ film

Efficient Verification Method with Random Vectors for Embedded Control RISC Cores (내장형 제어 RISC코어를 위한 효율적인 랜덤 벡터 기능 검증 방법)

  • Yang, Hun-Mo;Gwak, Seung-Ho;Lee, Mun-Gi
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.38 no.10
    • /
    • pp.735-745
    • /
    • 2001
  • Processors require both intensive and extensive functional verification in their design phase due to their general purpose. The proposed random vector verification method for embedded control RISC cores meets this goal by contributing assistance for conventional methods. The proposed method proved its effectiveness during the design of CalmRISCTM-32 developed by Yonsei Univ. and Samsung. It adopts a cycle-accurate instruction level simulator as a reference model, runs simulation in both the reference and the target HDL and reports errors if any difference is found between them. Consequently, it successfully covers errors designers easily pass over and establishes other new error check points.

  • PDF

스마트카 개발동향 및 당면과제

  • Lee, Jae-Gwan
    • Information and Communications Magazine
    • /
    • v.30 no.11
    • /
    • pp.32-38
    • /
    • 2013
  • 2020년 자동차산업의 핵심 키워드는 새로운 교통수단과 이동 서비스를 제공함으로써 새로운 비즈니스의 기회를 창출해야 하는 '이동성의 재발견', 글로벌시장의 다양한 소비자에게 신속하고 효과적으로 대응할 수 있는 시스템을 모색해야 하는 '전방위적 유연성', 미래사회 산업의 패러다임 변화에 대응하기 위해 자동차업체 이외의 new players의 참여를 유도하고 공존할 수 있는 열린 산업문화를 구축해야 하는 '소통과 협력', 미래경쟁력 확보를 위해 핵심기술의 선점과 상품화 노력을 강화해야 하는 '첨단기술의 융합'으로 요약할 수 있다. 그리고 미래 자동차산업의 경쟁력은 자동차 자체를 만드는 기술력 보다는 융합기술을 접목한 신서비스의 소비자 니즈 충족이 관건인 점을 감안할 때, 최근에 관심이 집중되고 있는 스마트카에 대한 적극적인 대처가 미래 자동차산업의 경쟁력을 확보하고 우리나라 자동차산업의 지속 성장을 보장할 수 있다고 판단된다. 이러한 스마트카는 운전자 지원이 중요하고 운전자 수용성, 사회적 수용성, 산업적 수용성의 기본원칙을 만족해야 하며 여기서 운전자 지원의 형태로는 인식의 지원, 판단의 지원, 조작의 지원을 그리고 지원의 기능으로는 크게 지각기능의 확대, 정보제공, 경보, 사고회피 지원제어, 운전부하 경감제어를 들 수 있다. 운전자 수용성이란 스마트카의 다양한 기능들이 가능한한 운전자에게 쉽게 전달되어야 하고 운전자가 이들 기능들을 과신하여 의존하는 일이 발생해서는 안된다는 것을 의미한다. 아울러 스마트카의 기능은 어떤 조건에서 효과가 어느 정도로 기대될까를 분명히 정해둘 필요가 있다. 즉 사회적 측면에서의 표준화, 법규화가 병행되어야 함을 의미하고 이것이 사회적 수용성이라고 할 수 있다. 마지막으로 산업적 수용성이란 자동차 산업은 기존 사업을 지속 성장시키고 new players에게는 새로운 사업에 참여할 수 있는 기회가 정당하게 주어져야 함을 의미한다.

Infrastructure for Network Applications based on Multi-Platform (멀티 플랫폼 기반 네트워크 응용을 위한 기반 구조)

  • 김진덕;진교홍
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2002.11a
    • /
    • pp.677-681
    • /
    • 2002
  • Several multi-user online applications which are operated by the existing fixed terminals(PC) are being changed into online application based on multi-platform operated by the several PC, PDA and mobile phones to perform concurrent works due to the popularization of mobile devices recently. This paper proposed the infrastructure for network applications based on multi-platform. We also proposed the methods of consistency control based on multi-platform, update propagation protocols among diverse clients which take the asymmetry of computing power and network bandwidth among each client into account. Moreover, we implemented a chatting application based on multi-platform and it showed the proposed infrastructure and methods perform well.

  • PDF