• 제목/요약/키워드: time-consistency

검색결과 819건 처리시간 0.036초

복제 웹 서버의 콘텐츠 동기화 알고리즘 (Consistency Maintenance Algorithm of Replica Web Servers)

  • 김선호;고훈;신용태
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2004년도 봄 학술발표논문집 Vol.31 No.1 (A)
    • /
    • pp.391-393
    • /
    • 2004
  • 인터넷상의 사용자와 대용량 콘텐츠의 급증에 따른 서비스 저하의 문제를 해결하기 위하여 웹 서버를 분산 설치하여 지역 서버로 하여금 클라이언트의 요청에 응답하도록 하는 콘텐츠 분산 네트워크(CDN)가 사용되고 있다. 그러나 원본 서버로부터 분산된 지역 서버에 콘텐츠를 복제하여 서비스하는 CDN 환경에서는 원본 서버와 복제 서버와의 콘텐츠 일관성을 유지하는 일이 중요한 문제이다. 그러므로 본 연구에서는 콘텐츠 특상에 따라 Adaptive TTL(Time to Live)을 적용하고 원본 서버와 복제 서버가 서로 협력하는 콘텐츠 동기화 알고리즘을 제안한다.

  • PDF

올바른 의학 논문 작성법 (입문) (How to write a medical paper: an introduction)

  • 황진복
    • Clinical and Experimental Pediatrics
    • /
    • 제52권7호
    • /
    • pp.756-765
    • /
    • 2009
  • This paper aims to provide an introduction to junior authors on how to write a medical paper in a clearer and more scientific manner. One important thing to be always remembered is that the reviewer and the reader will be reading your paper for the first time, and thus, you should make it as lucid as possible. You should pay attention to consistency in every regard in your paper. Use of the active voice usually makes the sentences shorter and clearer in meaning. Organize your content carefully and present it logically, avoiding unnecessary repetition in different sections. Give a diligent thought to every aspect; research is a work of the mind, not of the hands. Write technically, using powerful language. Most importantly, fulfill the exact submission requirements of the journal.

A Comparison of Size and Power of Tests of Hypotheses on Parameters Based on Two Generalized Lindley Distributions

  • Okwuokenye, Macaulay;Peace, Karl E.
    • Communications for Statistical Applications and Methods
    • /
    • 제22권3호
    • /
    • pp.233-239
    • /
    • 2015
  • This study compares two generalized Lindley distributions and assesses consistency between theoretical and analytical results. Data (complete and censored) assumed to follow the Lindley distribution are generated and analyzed using two generalized Lindley distributions, and maximum likelihood estimates of parameters from the generalized distributions are obtained. Size and power of tests of hypotheses on the parameters are assessed drawing on asymptotic properties of the maximum likelihood estimates. Results suggest that whereas size of some of the tests of hypotheses based on the considered generalized distributions are essentially ${\alpha}$-level, some are possibly not; power of tests of hypotheses on the Lindley distribution parameter from the two distributions differs.

Numerical Simulation of Natural Convection in Annuli with Internal Fins

  • Ha, Man-Yeong;Kim, Joo-Goo
    • Journal of Mechanical Science and Technology
    • /
    • 제18권4호
    • /
    • pp.718-730
    • /
    • 2004
  • The solution for the natural convection in internally finned horizontal annuli is obtained by using a numerical simulation of time-dependent and two-dimensional governing equations. The fins existing in annuli influence the flow pattern, temperature distribution and heat transfer rate. The variations of the On configuration suppress or accelerate the free convective effects compared to those of the smooth tubes. The effects of fin configuration, number of fins and ratio of annulus gap width to the inner cylinder radius on the fluid flow and heat transfer in annuli are demonstrated by the distribution of the velocity vector, isotherms and streamlines. The governing equations are solved efficiently by using a parallel implementation. The technique is adopted for reduction of the computation cost. The parallelization is performed with the domain decomposition technique and message passing between sub-domains on the basis of the MPI library. The results from parallel computation reveal in consistency with those of the sequential program. Moreover, the speed-up ratio shows linearity with the number of processor.

Successful ERP Operations: Process Integration Perspectives and an Agent-Based Support System

  • Park, Kwang-Ho
    • 지능정보연구
    • /
    • 제9권2호
    • /
    • pp.65-85
    • /
    • 2003
  • Any ERP system pushes a company toward full process integration and solves the fragmentation of information. However, the tight process integration can propagate and magnify mistakes made in one department into the other departments in real time. Thus, it can be posited that a central support system for the coordination can help ERP users and administrators dig out problems, take care of tedious validation and verification, and maintain process integration of ERP with great consistency. This paper proposes an agent-based ERP operations support system (EOSS) that aims at achieving and maintaining process integration of ERP at the highest level possible. With EOSS, the process integrity is monitored, with anomalies prevented as early as possible and repaired as precisely as possible.

  • PDF

예측필터를 이용한 확장칼만필터 고장검출 및 SDINS에의 적용 (Fault Detection for Extended Kalman Filter Using a Predictor and Its Application to SDINS)

  • 유재종
    • 한국군사과학기술학회지
    • /
    • 제9권3호
    • /
    • pp.132-140
    • /
    • 2006
  • In this paper, a new fault detection method for the extended Kalman filter, which uses a N-step predictor, is proposed. The N-step predictor performs the only time propagations for N-step intervals without measurement updates and its output is used as a monitoring signal for the fault detection. A consistency between the extended Kalman filter and the N-step predictor is tested to detect a fault. A test statistic is defined by the difference between the extended Kalman filter and the N-step predictor. The proposed method is applied to strapdown inertial navigation system (SDINS). By computer simulation, it is shown that the proposed method detects a fault effectively.

Variance components estimation in the presence of drift

  • Kim, Jaehee;Ogden, Todd
    • Communications for Statistical Applications and Methods
    • /
    • 제23권1호
    • /
    • pp.33-45
    • /
    • 2016
  • Variance components should be estimated based on mean change when the mean of the observations drift gradually over time. Consistent estimators for the variance components are studied for a particular modeling situation with some underlying functions or drift. We propose a new variance estimator with Fourier estimation of variations. The consistency of the proposed estimator is proved asymptotically. The proposed procedures are studied and compared empirically with the variance estimators removing trends. The result shows that our variance estimator has a smaller mean square error and depends on drift patterns. We estimate and apply the variance to Nile River flow data and resting state fMRI data.

아동의 항상성개념 발달에 관한 연구 - 자신 및 타인의 개인특성을 중심으로 - (Development of the Character Constancy Concept: Self and Others)

  • 김창하
    • 아동학회지
    • /
    • 제8권1호
    • /
    • pp.15-29
    • /
    • 1987
  • The purpose of the present research was to investigate (I) the acquisition of character constancy of self and others as a function of age; (2) the pattern of acquisition of character constancy, and (3) the relationships between character constancy and conservation of number and mass. The subjects of this study were 160 children, 20 boys and 20 girls at each grade level, kindergarter through grade 3. The Character Constancy Tasks devised bi Rotenberg (1982) and conservation task of number and mass were administered to each child. Chi square, Guttman Scale analysis and Pearson's Correlation were used for the statistical analysis of data. The findings showed that there was increase with age in character constancy of others and of sell in that there was increase with age in children's belief that the characteristics of another person are stable across time and consistent despite changes in a person's appearance. Character constancy of others and of self were acquired in the developmental stages of identity, stability, and consistency. Character constancy of others and self correlated with the conservation of number and mass.

  • PDF

Efficiency Comparison between Chlorine and Chlorine Dioxide to Control Bacterial Regrowth in Water Distribution System

  • Lee, Yoon-Jin
    • 한국환경보건학회지
    • /
    • 제32권4호
    • /
    • pp.282-291
    • /
    • 2006
  • This study investigated the inactivation of the total coliform, an indicator organism in chlorine and chlorine in order to control microbial regrowth for water distribution systems and select an appropriate disinfection strategy for drinking water systems. The disinfection effects of chlorine and chlorine dioxide with regard to the dosage of disinfectant, contact time and DOC was investigated experimentally. In spite of the consistency of chlorine residuals at approximately 0.2 mg/l, bacteria regrowth was detected in the distribution system and it was confirmed by the scanning electron microscope results. The influence of organic carbon change on the killing effect of chlorine dioxide was strong.

Effects of Chaff as Bulking Materials on Aerobic Composting of Food Wastes

  • Park, Seok-Hwan
    • 한국환경보건학회:학술대회논문집
    • /
    • 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
    • /
    • pp.208-212
    • /
    • 2003
  • This study was performed to examine the effects of chaff as bulking materials on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor Control, Ch-1, Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4, respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wastes to chaff resulted in the ascending of the highest reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more fast time of pH ascending. The lowering of the volume ratio of food wastes to chaff resulted in the more fast consistency in the weight and volume reduction rates. Salinities were condensed by reaction days. The final salinity of Control was 2.79%, and the final range of salinities of chaff mixtures was 2.18 - 2.37%.

  • PDF