Data mining reactor fuel grab load trace data to support nuclear core condition monitoring

A critical component of an advanced-gas cooled reactor (AGR) station is the graphite core. As a station ages, the graphite bricks that comprise the core can distort and may eventually crack. As the core cannot be replaced the core integrity ultimately determines the station life. Monitoring these distortions is usually restricted to the routine outages, which occur every few years, as this is the only time that the reactor core can be accessed by external sensing equipment. However, during weekly refueling activities measurements are taken from the core for protection and control purposes. It is shown in this paper that these measurements may be interpreted for condition monitoring purposes, thus potentially providing information relating to core condition on a more frequent basis. This paper describes the data-mining approach adopted to analyze this data and also describes a software system designed and implemented to support this process. The use of this software to develop a model of expected behavior based on historical data, which may highlight events containing unusual features possibly indicative of brick cracking, is also described. Finally, the implementation of this newly acquired understanding in an automated analysis system is described

Knowledge, management and intelligent decision support for protection scheme design and application in electrical power systems

The paper describes a research project carried out inconjunction with two major UK utilities, focusing on the introduction of knowledge management and intelligent decision support to the existing protection design and application processes operated within both companies. A brief overview is provided of the generic design process, and the development of the web-based Design Engineering Knowledge Application System (DEKAS). This system incorporates intelligent case based reasoning (CBR) functionality to address the knowledge management and decision support requirements of each company's design process. The perceived key benefits of DEKAS relating to the management and utilisation of the data, information and knowledge throughout the protection design process is also discussed

Intelligent graphite core condition monitoring

Condition monitoring of graphite cores has increased significantly in recent years, as the safety cases required to continue operation of Advanced Gas Cooled Reactors (AGR) have evolved. This paper describes the development and implementation of intelligent systems designed to automate and formalise the CM analyses and tasks performed within the remit of the Monitoring Assessment Panels, which are currently being rolled out across the AGR fleet. The implementation of such systems is found to depend crucially on the involvement of station staff at each step of design and implementation, which is highlighted by the successful deployment of second iterations of the IMAPS system for managing reactor observations and the BETA system for automatically analysing refuelling data. Though each system was initially based on an individual analysis or tasks, this paper describes more recent work to allow closer integration of the systems as they are developed, in order to maximise the use of the available data while minimising duplication of effort and required operator time

The Influence of an Orienting Task on the Memory Performance of Children with Reading Problems

This study investigated the hypothesis that differences in performance between reading disabled and normal children on a rote memory task could be eliminated if both groups were induced to process the material to be remembered in the same manner. The free recall of fourth-grade good and poor readers was tested following a free study period and the performance of an orienting task that required subjects to sort the material into taxonomic categories. There was a significant group by conditions interaction, with recall differences in the free study condition being eliminated following performance of the orienting task. The results have important implications for theoretical explanations of performance deficits in reading disabled children.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68893/2/10.1177_002221947901200608.pd

Truncated Levy Random Walks and Generalized Cauchy Processes

A continuous Markovian model for truncated Levy random walks is proposed. It generalizes the approach developed previously by Lubashevsky et al. Phys. Rev. E 79, 011110 (2009); 80, 031148 (2009), Eur. Phys. J. B 78, 207 (2010) allowing for nonlinear friction in wondering particle motion and saturation of the noise intensity depending on the particle velocity. Both the effects have own reason to be considered and individually give rise to truncated Levy random walks as shown in the paper. The nonlinear Langevin equation governing the particle motion was solved numerically using an order 1.5 strong stochastic Runge-Kutta method and the obtained numerical data were employed to calculate the geometric mean of the particle displacement during a certain time interval and to construct its distribution function. It is demonstrated that the time dependence of the geometric mean comprises three fragments following one another as the time scale increases that can be categorized as the ballistic regime, the Levy type regime (superballistic, quasiballistic, or superdiffusive one), and the standard motion of Brownian particles. For the intermediate Levy type part the distribution of the particle displacement is found to be of the generalized Cauchy form with cutoff. Besides, the properties of the random walks at hand are shown to be determined mainly by a certain ratio of the friction coefficient and the noise intensity rather then their characteristics individually.Comment: 7 pages, 3 figure

A 14-year experience with kidney transplantation.

Between November, 1962 and August, 1975, 668 kidney transplants were done in 556 consecutive patients at Denver, Colorado. The Denver experience has been divided into 7 periods of time, according to the conditions of care during each period. The results in related transplantation have changed little during the decade beginning in 1966. The results in unrelated transplantation have not materially changed since 1968. The long-term patient survival after related transplantation has been better than after cadaver transplantation. The results of transplantation in 57 children ages 3 to 18 years have been slightly better than the results of adult transplantation. The outcome of kidney transplantation and the feasibility of improving this therapy with present techniques are limited by our inability to accurately match each patient with the immunologically best donor and by our inability to precisely control the immune system of the recipient. Rejection is still the main reason for graft loss, and sepsis remains the main cause of patient mortality. More specific and less toxic means of achieving graft acceptance are needed before a higher level of patient service can be realized. However, even with the tools now available, thousands of recipients throughout the world have been returned to useful lives

Religious Values, Practices and Pregnancy Outcomes: A Comparison of the Impact of Sect and Mainstream Christian Affiliation

In this report 6566 women enrolled in the Mater-University of Queensland Study of Pregnancy (MUSP) were separated into three groups; members of religious sects, Christians who attend church frequently and Christians who are infrequent attenders. These three groups, respectively labelled Christian sects, Christian attenders and lukewarm Christians were compared on a number of social background, lifestyle and pregnancy outcome variables. The sect members appeared to have the most favourable health, lifestyles and healthy babies at delivery, though this latter finding appears attributable to specific characteristics of the mother and her lifestyle. On most measures the children of lukewarm Christians appear to manifest the worst health while Christian attenders form a group whose children's health is between that of sect members and lukewarm Christians

Improved Effective Potential in Curved Spacetime and Quantum Matter - Higher Derivative Gravity Theory

\noindent{\large\bf Abstract.} We develop a general formalism to study the renormalization group (RG) improved effective potential for renormalizable gauge theories ---including matter-$R^2$-gravity--- in curved spacetime. The result is given up to quadratic terms in curvature, and one-loop effective potentials may be easiliy obtained from it. As an example, we consider scalar QED, where dimensional transmutation in curved space and the phase structure of the potential (in particular, curvature-induced phase trnasitions), are discussed. For scalar QED with higher-derivative quantum gravity (QG), we examine the influence of QG on dimensional transmutation and calculate QG corrections to the scalar-to-vector mass ratio. The phase structure of the RG-improved effective potential is also studied in this case, and the values of the induced Newton and cosmological coupling constants at the critical point are estimated. Stability of the running scalar coupling in the Yukawa theory with conformally invariant higher-derivative QG, and in the Standard Model with the same addition, is numerically analyzed. We show that, in these models, QG tends to make the scalar sector less unstable.Comment: 23 pages, Oct 17 199