• Title/Summary/Keyword: time-consistency

Search Result 816, Processing Time 0.035 seconds

Design of Main-Memory Database Prototype System using Fuzzy Checkpoint Technique in Real-Time Environment (실시간 시스템에서 퍼지 검사점을 이용한 주기억 데이터베이스 프로토타입 시스템의설계)

  • Park, Yong-Mun;Lee, Chan-Seop;Choe, Ui-In
    • The Transactions of the Korea Information Processing Society
    • /
    • v.7 no.6
    • /
    • pp.1753-1765
    • /
    • 2000
  • As the areas of computer application are expanded, real-time application environments that must process as many transactions as possible within their deadlines, such as a stock transaction systems, ATM switching systems etc, have been increased recently. The reason why the conventional database systems can't process soft real-time applications is the lack of prediction and poor performance on processing transaction's deadline. If transactions want to access data stored at the secondary storage, they can not satisfy requirements of real-time applications because of the disk delay time. This paper designs a main-memory database prototype systems to be suitable to real-time applications and then this system can produce rapid results without disk i/o as all of the information are loaded in main memory database. In thesis proposed the improved techniques with respect to logging, checkpointing, and recovering in our environment. In order to improve the performance of the system, a) the frequency of log analysis and redo processing is reduced by the proposed redo technique at system failure, b) database consistency is maintained by improved fuzzy checkpointing. The performance model is proposed which consists of two parts. The first part evaluates log processing time for recovery and compares with other research activities. The second part examines checkpointing behavior.

  • PDF

Performance Management through Time-Cost Integration in Construction Project (비용-일정 통합관리를 통한 건축공사 실적관리)

  • Kim Dong-Jin;Lim Hyoung Chul;Choi Jung Suk
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • autumn
    • /
    • pp.379-382
    • /
    • 2001
  • In domestic construction industry, time and cost has been managed separately in most cases. Usually projects are managed focused on cost, so time is not yet managed systematically. Project performance in these managemental situation can not be assessed correctly. This would cause project delay, cost overrun, productivity loss. Therefore it is needed to adopt earned value concept, an approach used in the management and control of project costs and schedules. Using this EV concept through time-cost integration, project can be managed properly based on the consistency, predictability, and reliability of the performance data. This paper proposed time and cost integration process, proper PMT method, and practical performance management model through time and cost integration.

  • PDF

Proposal an Alternative Data Pipeline to Secure the Timeliness for Official Statistical Indicators (공식발표 통계지표의 적시성 확보를 위한 대안 데이터 파이프라인 구축제안)

  • Yongbok Cho;Dowan Kim
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.28 no.5
    • /
    • pp.89-108
    • /
    • 2023
  • This study provides a comprehensive analysis of recent studies conducted on the topic of nowcasting in order to enhance the accuracy and promptness of official statistical data. Furthermore, we propose an alternative approach involving the utilization of real-time data and its corresponding collection methods to effectively operate a real-time nowcasting model capable of accurately capturing the current economic condition. We explore high-frequency real-time data that can predict economic indicators in both the public and private sectors and propose a pipeline for data collection processing and modeling that is based on cloud platforms. Furthermore we validate the essential elements required for the implementation of real-time nowcasting, as well as their data management protocols to ensure the reliability and consistency needed for accurate forecasting of official statistical indicators.

A Methodology for Consistent Design of User Interaction (일관성 있는 사용자 인터랙션 설계를 위한 방법론 개발)

  • Kim, Dong-San;Yoon, Wan-Chul
    • 한국HCI학회:학술대회논문집
    • /
    • 2009.02a
    • /
    • pp.961-970
    • /
    • 2009
  • Over the last decade, interactive devices such as mobile phones have become complicated drastically mainly because of feature creep, the tendency for the number of features in a product to rise with each release of the product. One of the ways to reduce the complexity of a multi-functional device is to design it consistently. Although the definition of consistency is elusive and it is sometimes beneficial to be inconsistent, in general, consistently designed systems are easier to learn, easier to remember, and causing less errors. In practice, however, it is often not easy to design the user interaction or interface of a multi-functional device consistently. Since the interaction design of a multi-functional device should deal with a large number of design variables and relations among them, solving this problem might be very time-consuming and error-prone. Therefore, there is a strong need for a well-developed methodology that supports the complex design process. This study has developed an effective and efficient methodology, called CUID (Consistent Design of User Interaction), which focuses on logical consistency rather than physical or visual consistency. CUID deals with three main problems in interaction design: procedure design for each task, decisions of available operations(or functions) for each system state, and the mapping of available operations(functions) and interface controls. It includes a process for interaction design and a software tool for supporting the process. This paper also demonstrates how CUID supports the consistent design of user interaction by presenting a case study. It shows that the logical inconsistencies of a multi-functional device can be resolved by using the CUID methodology.

  • PDF

Development of Drought Index based on Streamflow for Monitoring Hydrological Drought (수문학적 가뭄감시를 위한 하천유량 기반 가뭄지수 개발)

  • Yoo, Jiyoung;Kim, Tae-Woong;Kim, Jeong-Yup;Moon, Jang-Won
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.37 no.4
    • /
    • pp.669-680
    • /
    • 2017
  • This study evaluated the consistency of the standard flow to forecast low-flow based on various drought indices. The data used in this study were streamflow data at the Gurye2 station located in the Seomjin River and the Angang station located in the Hyeongsan River, as well as rainfall data of nearby weather stations (Namwon and Pohang). Using streamflow data, the streamflow accumulation drought index (SADI) was developed in this study to represent the hydrological drought condition. For SADI calculations, the threshold of drought was determined by a Change-Point analysis of the flow pattern and a reduction factor was estimated based on the kernel density function. Standardized runoff index (SRI) and standardized precipitation index (SPI) were also calculated to compared with the SADI. SRI and SPI were calculated for the 30-, 90-, 180-, and 270-day period and then an ROC curve analysis was performed to determine the appropriate time-period which has the highest consistency with the standard flow. The result of ROC curve analysis indicated that for the Seomjin River-Gurye2 station SADI_C3, SRI30, SADI_C1, SADI_C2, and SPI90 were confirmed in oder of having high consistency with standard flow under the attention stage and for the Hyeongsan River-Angang station, SADI_C3, SADI_C1, SPI270, SRI30, and SADI_C2 have order of high consistency with standard flow under the attention stage.

Concurrency Control and Consistency Maintenance of Cached Spatial Data in Client-Server Environment (클라이언트-서버 환경에서 캐쉬된 공간 데이터의 동시성 제어 및 일관성 유지 기법)

  • Shin, Young-Sang;Hong, Bong-Hee
    • Journal of KIISE:Databases
    • /
    • v.28 no.3
    • /
    • pp.512-527
    • /
    • 2001
  • In a client-server spatial database, it is desirable to maintain the cached data in a client side to minimize the communication overhead across a network. This paper deals with the issues of concurrency and consistency of map updates in this environment. A client transaction to update map data is an interactive work and takes a long time to complete it. The map update in a client site may affect the other sites'updates because of dependencies between spatial data stored at different sites. The concurrent updates should be propagated to the other clients as well as the server to keep the consistency of map replicated in a client cache, and also the communication overhead of the update propagation should be minimized not to lose the benefit of caching. The newly proposed cache region locking with CR lock and CX lock controls the update dependency due to spatial relationships. CS lock and COD lock are suggested to use optimistic detection-based approaches for guaranteeing the consistency of cached client data. The cooperative update protocol uses these extended locking primitives and Spatial Relationship-based 2PC (SR-based 2PC). This paper argues that the concurrent updates of cached client spatial data can be achieved by deciding on collaborative updates or independent updates based on spatial relationships.

  • PDF

Optimizing and Modeling Brightness Development in Peroxide Bleaching of Thermomechanical Pulp

  • Yoon, Byung-Ho;Wang, Li-Jun;Park, Soo-Kyoung;Kim, Dong-Yoon
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
    • /
    • 1999.11a
    • /
    • pp.180-186
    • /
    • 1999
  • Alkaline peroxide bleaching of (chemi) mechanical pulp is a very complicated system where various process factors affect the bleaching performance and pulp properties. Traditional on-factor-at a time method is ineffective and costly in finding the optimal bleaching conditions. In this study statistical experimental methods which include three steps. I. e. screening, response surface modeling and optimization, were used to find the conditions for maximal brightness development during one stage alkaline peroxide bleaching of TMP which had an initial brightness of 54.5% Elerpho. The TMP was pretreated with EDTA(0.5% on O. D. pulp. consistency, $30^{\circ}C$ for 60 minutes) and bleached in a 2L Mark V Quantum Reactor at 750rpm, 7.5% of bleaching consistency and with 0.05% magnesium sulfate addition. The ranges of other factors studied were 1~5% hydrogen peroxide on O. D plup, 1~4% sodium hydroxide on O. D pulp and 1~4% sodium silicate on O. D pulp, reaction temperature 50~$90^{\circ}C$ and reaction time 40~180minutes. A models with good predictability was established and the maximal brightness after one stage bleaching was found to be 70% Elerpho at $50^{\circ}C$, 50 minutes 5% hydrogen peroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D. pulp 3.2~3.4% sodium hydroxide on O. D pulp and 4% silicate on O. D pulp. However further studies on other pulp properties such as strength and brightness stability shall be carried out in order to find out the optimal bleaching conditions.

  • PDF

Ground-Motion Prediction Equations based on refined data for dynamic time-history analysis

  • Moghaddam, Salar Arian;Ghafory-Ashtiany, Mohsen;Soghrat, Mohammadreza
    • Earthquakes and Structures
    • /
    • v.11 no.5
    • /
    • pp.779-807
    • /
    • 2016
  • Ground Motion Prediction Equations (GMPEs) are essential tools in seismic hazard analysis. With the introduction of probabilistic approaches for the estimation of seismic response of structures, also known as, performance based earthquake engineering framework; new tasks are defined for response spectrum such as the reference criterion for effective structure-specific selection of ground motions for nonlinear time history analysis. One of the recent efforts to introduce a high quality databank of ground motions besides the corresponding selection scheme based on the broadband spectral consistency is the development of SIMBAD (Selected Input Motions for displacement-Based Assessment and Design), which is designed to improve the reliability of spectral values at all natural periods by removing noise with modern proposed approaches. In this paper, a new global GMPE is proposed by using selected ground motions from SIMBAD to improve the reliability of computed spectral shape indicators. To determine regression coefficients, 204 pairs of horizontal components from 35 earthquakes with magnitude ranging from Mw 5 to Mw 7.1 and epicentral distances lower than 40 km selected from SIMBAD are used. The proposed equation is compared with similar models both qualitatively and quantitatively. After the verification of model by several goodness-of-fit measures, the epsilon values as the spectral shape indicator are computed and the validity of available prediction equations for correlation of the pairs of epsilon values is examined. General consistency between predictions by new model and others, especially, in short periods is confirmed, while, at longer periods, there are meaningful differences between normalized residuals and correlation coefficients between pairs of them estimated by new model and those are computed by other empirical equations. A simple collapse assessment example indicate possible improvement in the correlation between collapse capacity and spectral shape indicators (${\varepsilon}$) up to 20% by selection of a more applicable GMPE for calculation of ${\varepsilon}$.

Studies on the Pulping Conditions of Separating Useful Components from Disposable Diaper Waste (폐 일회용 기저귀의 유용 성분 회수를 위한 해리조건 연구)

  • Lee, Tai-Ju;Choi, Do-Chim;Nam, Yun-Seok;Jo, Jun-Hyung;Lee, Ho-Seon;Ryu, Jeong-Yong
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.47 no.2
    • /
    • pp.1-8
    • /
    • 2015
  • Disposable diaper has been used in order to handle urine and feces conveniently. At present the amount of disposable diaper waste increases gradually. Incineration and landfill have been the only ways to dispose of disposable diapers. However, if they are disposed by landfill, decomposition will take more than one hundred years. In addition, another way of dispose incineration has caused air pollution. Therefore, it is necessary to study recycling process for disposable diaper since plastic and wood fibers of diaper are useful materials to recycle. In this study, pulping condition of disposable diaper waste was studied in order to effectively separate the components. Recovery rates of plastic and fibers were analyzed under different pulping conditions. It was found that optimum pulping consistency was 5%, time was 60 minutes, temperature was $50^{\circ}C$, and cut size is $21cm{\times}21cm$. The recovery rate of plastic and fibers can be achieved above 70% under the optimum pulping condition.

Design and Implementation of a Distributed Object Programming Language supporting Peer Replicated Object Model (대등관계 복제객체 모델을 지원하는 분산 객체 프로그래밍 언어의 설계 및 구현)

  • Sin, Beom-Ju;Lee, Dong-Hyeon
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.5 no.4
    • /
    • pp.449-456
    • /
    • 1999
  • 본 논문은 C++에 분산 객체 프로그래밍 기능을 추가한 D++ 언어를 제안한다. 대등관계 복제객체 모델을 지원하는 D++는 분산 클래스의 정의, 멤버 함수의 일치성 제어 정의 기능, 그리고 영구 객체 이름에 기반한 분산 객체를 정의할 수 있는 언어 구조를 제공한다. D++ 프로그램에서 새로이 생성되는 분산 객체는 생성 시에 제공되는 객체의 영구 이름과 동일한 영구 이름을 갖는 분산 객체가 존재할 경우 해당 객체들과 복제 관계를 유지함으로써 정보를 공유한다. 각 복제 객체들은 서로 간에 대등한 관계를 가지며, 멤버 함수 정의 시에 기술되는 특성에 따라 일치성이 유지된다. 이 같은 D++의 분산 객체 모델은 실시간 그룹웨어의 기본 요구 사항인 분산 환경에서의 정보 공유 및 사건 공지 기능을 자연스럽게 해결해 주기 때문에 실시간 그룹웨어의 개발을 효율적으로 지원할 수 있을 것으로 기대한다. Abstract This paper proposes D++ programming language that is an extension of C++ for distributed object oriented programming. The D++, which supports peer-to-peer object model, provides new language constructs for the definition of distributed classes, the definition of the consistency control of the member function and the definition of distributed object variables with the persistent name. In D++, when the persistent name of a newly created distributed object is same as that of an existing distributed object, the new distributed object replicates object state of the existing distributed object and thus they share the object state. The replicas have peer relation and the consistency among them is maintained according to the characteristic described on the definition of designated member functions. It is expected that D++ language increases efficiency in development of real-time groupware because the distributed object model of D++ naturally supports the information sharing and event notification that are the basic functions required when building real-time groupware.