Response time variations in an online search system

نویسنده

  • Michael D. Cooper
چکیده

The response time characteristics of the National Library of Medicine's (NLM) ELHILL bibliographic search system are examined in this article. Transactions for a five-week period are analyzed and average response times are calculated for typical search commands, by time of day, and by file being searched. Overall, the response time of the system was found to be 2.1 seconds, a very low value. Based on statistical tests of significance applied to the data, it was concluded that response time differences can be explained in terms of the number of users on the system and not the command issued by the user nor the file the user searched.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

An Improved MPPT Method of Wind Turbine Based on HCS Method by Using Fuzzy Logic System

In this paper presents a Maximum Power Point Tracking (MPPT) technique based on the Hill Climbing Search (HCS) method and fuzzy logic system for Wind Turbines (WTs) including of Permanent Magnet Synchronous Generator (PMSG) as generator. In the conventional HCS method the step size is constant, therefor both steady-state response and dynamic response of method cannot provide at the same time an...

متن کامل

Online Aggregation of Coherent Generators Based on Electrical Parameters of Synchronous Generators

This paper proposes a novel approach for coherent generators online clustering in a large power system following a wide area disturbance. An interconnected power system may become unstable due to severe contingency when it is operated close to the stability boundaries. Hence, the bulk power system controlled islanding is the last resort to prevent catastrophic cascading outages and wide area bl...

متن کامل

The Effects of the Moving Load and the Attached Mass-Spring-Damper System Interactions on the Dynamic Responses of the Composite Plates: An Analytical Approach

In the current study, the effects of interactions of the moving loads and the attached mass-spring-damper systems of the composite plates on the resulting dynamic responses are investigated comprehensively, for the first time, using the classical plate theory. The solution of the coupled governing system of equations is accomplished through tracing the spatial variations using a Navier-type sol...

متن کامل

An Optimized Online Secondary Path Modeling Method for Single-Channel Feedback ANC Systems

This paper proposes a new method for online secondary path modeling in feedback active noise control (ANC) systems. In practical cases, the secondary path is usually time-varying. For these cases, online modeling of secondary path is required to ensure convergence of the system. In literature the secondary path estimation is usually performed offline, prior to online modeling, where in the prop...

متن کامل

Fractional order Adaptive Terminal Sliding Mode Controller Design for MPPT in a Solar Cell under Normal and Partial Shading Condition

In this paper, by combining fractional calculus and sliding mode control theory, a new fractional order adaptive terminal sliding mode controller is proposed for the maximum power point tracking in a solar cell. To find the maximum power point, the incremental conductance method has been used. First, a fractional order terminal sliding mode controller is designed in which the control law depend...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of the American Society for Information Science. American Society for Information Science

دوره 34 6  شماره 

صفحات  -

تاریخ انتشار 1983