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Systematic Method (systematic + method)
Selected AbstractsExperimental analysis of a mass storage systemCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 15 2006Shahid Bokhari Abstract Mass storage systems (MSSs) play a key role in data-intensive parallel computing. Most contemporary MSSs are implemented as redundant arrays of independent/inexpensive disks (RAID) in which commodity disks are tied together with proprietary controller hardware. The performance of such systems can be difficult to predict because most internal details of the controller behavior are not public. We present a systematic method for empirically evaluating MSS performance by obtaining measurements on a series of RAID configurations of increasing size and complexity. We apply this methodology to a large MSS at Ohio Supercomputer Center that has 16 input/output processors, each connected to four 8 + 1 RAID5 units and provides 128 TB of storage (of which 116.8 TB are usable when formatted). Our methodology permits storage-system designers to evaluate empirically the performance of their systems with considerable confidence. Although we have carried out our experiments in the context of a specific system, our methodology is applicable to all large MSSs. The measurements obtained using our methods permit application programmers to be aware of the limits to the performance of their codes. Copyright © 2006 John Wiley & Sons, Ltd. [source] A systematic method for the development of a three-phase transformer non-linear modelINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 8 2010Andreas D. Theocharis Abstract In this work, a novel three-phase transformer non-linear model is developed. The proposed model takes into account the magnetic core topology and the windings connections. The non-linear characteristic curve of the core material is introduced by its magnetization curve or by its hysteresis loop using the mathematical hysteresis model proposed by Tellinen or the macroscopic hysteresis model proposed by Jiles,Atherton. The eddy currents effects are included through non-linear resistors using Bertotti's work. The proposed model presents several advantages. An incremental linear circuit, having the same topology with the magnetic circuit of the core, is used in order to directly write the differential equations of the magnetic part of the transformer. The matrix Ld that describes the coupling between the windings of the transformer is systematically derived. The electrical equations of the transformer can be easily written for any possible connection of the primary and secondary windings using the unconnected windings equations and transformation matrices. The proposed methods for the calculation of the coupling between the windings, the representation of the eddy currents and the inclusion of the core material characteristic curve can be used to develop a transformer model appropriate for the EMTP/ATP-type programs. Copyright © 2009 John Wiley & Sons, Ltd. [source] A method for fast simulation of multiple catastrophic faults in analogue circuitsINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 3 2010Micha, Tadeusiewicz Abstract The paper offers an efficient method for simulation of multiple catastrophic faults in linear AC circuits. The faulty elements are either open circuits or short circuits. The method exploits the well-known Householder formula in matrix theory to find the node voltages deviations due to the perturbations of some circuit elements. The main achievement of the paper is a systematic method for performing the simulation of all combinations of the multiple catastrophic faults. The method includes two new procedures enabling us to find very efficiently the node impedance matrix of the nominal circuit and inverses of some matrices corresponding to different fault combinations. The procedures are the crucial point of this approach and make it very efficient. Consequently, the amount of the computing power needed to carry out all the simulations is significantly reduced. Numerical examples illustrating the proposed approach are provided. Copyright © 2008 John Wiley & Sons, Ltd. [source] Systematic design method of stabilization fuzzy controllers for pendulum systemsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 8 2001Jianqiang Yi A systematic method to construct stabilization fuzzy controllers for a single pendulum system and a series-type double pendulum system is presented based on the single input rule modules (SIRMs) dynamically connected fuzzy inference model. The angle and angular velocity of each pendulum and the position and velocity of the cart are selected as the input items. Each input item is given with a SIRM and a dynamic importance degree. All the SIRMs have the same rule setting. The dynamic importance degrees use the absolute value(s) of the angle(s) of the pendulum(s) as the antecedent variable(s). The dynamic importance degrees are designed such that the upper pendulum angular control takes the highest priority and the cart position control takes the lowest priority when the upper pendulum is not balanced upright. The control priority orders are automatically adjusted according to control situations. The simulation results show that the proposed fuzzy controllers have high generalization ability to completely stabilize a wide range of single pendulum systems and series-type double pendulum systems in short time. By extending the architecture, a stabilization fuzzy controller for a series-type triple pendulum system is even possible. © 2001 John Wiley & Sons, Inc. [source] Performance of block-coded land mobile satellite systemsINTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 3 2008Chang-Ming Lee Abstract Although various measurements have indicated that mobile satellite channels are not memoryless, most related coded system performance analysis assumes perfect interleaving is in place so that the effect of channel memory can be completely ignored. This paper presents a systematic method to accurately and efficiently predict the performance of errors-and-erasures or errors-only decoders for block-coded systems in general mobile satellite channels. Numerical results are provided to validate our analytic results. Copyright © 2008 John Wiley & Sons, Ltd. [source] The optimum design of 6-DOF isotropic parallel manipulatorsJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 6 2005K. Y. Tsai How to obtain 6-DOF parallel manipulators with optimum global isotropy is investigated in this paper. A systematic method is first presented to get isotropic parallel designs. A measure for spatial isotropy is then proposed to evaluate and compare the global isotropy of obtained manipulators. Efficient methods to find the minimum and maximum singular values of matrices are developed to facilitate the evaluation process. © 2005 Wiley Periodicals, Inc. [source] Nurse staffing levels revisited: a consideration of key issues in nurse staffing levels and skill mix researchJOURNAL OF NURSING MANAGEMENT, Issue 6 2009BSc (Hons), MARIA FLYNN RGN Aim, This paper revisits the published evidence relating to how nurse staffing levels impact on patient, nurse and service outcomes and considers the implications of this body of research for nurse managers in their quest to determine optimum nursing numbers. Background, Within the context of the recognized global nursing shortage and particular local pressures within international health services, questions of appropriate nurse staffing levels and skill mix are once again becoming increasingly important. It would seem that the determination of optimum nurse staffing levels and skill mix is a central issue in relation to health service governance, service user involvement, as well as in the recruitment, retention and well-being of nursing staff across the service sectors. Methods, A review of published evidence was carried out, applying key principles of the systematic method, in order to facilitate the identification of current factors and issues in nurse staffing levels research. The review did not seek to address a specific research question. The search covered 10 years from 1998 to 2008 and identified more than 500 relevant papers, giving a wide international perspective. Key issues, The majority of research in the field relates to the acute service sector and there are considerable similarities in issues that transcend international boundaries. Much of the research focuses on the impact on patients and nurses of ,poor' nurse staffing levels. More recent studies have explored the impact of nurse staffing levels on the service organization itself. However, while there may be an association between models of nurse staffing and outcomes, there is insufficient evidence to establish a causal relationship between these factors. In this context it is perhaps time to reconsider how nursing outcomes are defined and measured. Implications for nursing management and conclusion, Nurse managers, commissioners of services and workforce planners need to be cognisant of key issues and analyses in the consideration of nurse staffing levels. Not least of these is the need for a healthy degree of caution regarding the supposed objectivity, scientific basis, or evidence base, for rational calculation of optimum nurse staffing levels. [source] Effective Contracting of Social ServicesNONPROFIT MANAGEMENT & LEADERSHIP, Issue 1 2001Barbara Peat The continued growth in the use of privatization for the delivery of social services increases the need for a systematic method to analyze the contracting process. Using a modified form of the basic systems model, the authors examine the impact of antecedents and situational factors and explore the use of traditional management steps in the contracting process. The authors focus on one state's experience with contracting to explore the implications of such a model. [source] Bayesian analysis for weighted mean-squared error in dual response surface optimizationQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 5 2010In-Jun Jeong Abstract Dual response surface optimization considers the mean and the variation simultaneously. The minimization of mean-squared error (MSE) is an effective approach in dual response surface optimization. Weighted MSE (WMSE) is formed by imposing the relative weights, (,, 1,,), on the squared bias and variance components of MSE. To date, a few methods have been proposed for determining ,. The resulting , from these methods is either a single value or an interval. This paper aims at developing a systematic method to choose a , value when an interval of , is given. Specifically, this paper proposes a Bayesian approach to construct a probability distribution of ,. Once the distribution of , is constructed, the expected value of , can be used to form WMSE. Copyright © 2009 John Wiley & Sons, Ltd. [source] A systematic approach to biological control agent exploration and prioritisation for prickly acacia (Acacia nilotica ssp. indica)AUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 4 2006K Dhileepan Abstract, Agent selection for prickly acacia has been largely dictated by logistics and host specificity. Given that detailed ecological information is available on this species in Australia, we propose that it is possible to select agents based on agent efficacy and desired impact on prickly acacia demography. We propose to use the ,plant genotype' and ,climatic' similarities as filters to identify areas for future agent exploration; and plant response to herbivory and field host range as ,predictive' filters for agent prioritisation. Adopting such a systematic method that incorporates knowledge from plant population ecology and plant,herbivore interactions makes agent selection decisions explicit and allow more rigorous evaluations of agent performance and better understanding of success and failure of agents in weed biological control. [source] Review and meta-analysis of the phenomenology and clinical characteristics of mania in children and adolescentsBIPOLAR DISORDERS, Issue 6 2005Robert A Kowatch Objective:, Using predetermined criteria for study quality and methods, a literature review and meta-analysis of seven reports about pediatric bipolar disorder (BPD) was conducted to determine if there is a consistent picture of the phenomenology and clinical characteristics of BPD in children and adolescents. Methods:, Searches were conducted in MedLine and PsycINFO using the terms mania, BPD, children and adolescents, and was limited to published articles in peer-reviewed journals. Seven reports were selected that met the following criteria: a systematic method for the elicitation and reporting of symptoms and clinical characteristics of subjects; subjects were interviewed by a trained researcher or clinician; ages 5,18 years; use of a diagnostic system, either DSM or RDC for categorization; a consensus method for the establishment of the diagnosis of BPD. Results:, Most DSM-IV symptoms of mania were common in the children and adolescents with BPD with the most common symptoms being increased energy, distractibility, and pressured speech. On average, four of five bipolar cases also showed threshold levels of irritable mood and grandiosity, and more than 70% of all cases showed elated/euphoric mood, decreased need for sleep, or racing thoughts. Roughly 69% of cases also showed poor judgment, whereas only half of bipolar cases demonstrated flight of ideas, and slightly more than one-third showed hypersexuality or psychotic features. Conclusions:, The clinical picture that emerges is that of children or adolescents with periods of increased energy (mania or hypomania), accompanied by distractibility, pressured speech, irritability, grandiosity, racing thoughts, decreased need for sleep and euphoria/elation. [source] A typology of stakeholder participation for company environmental decision-makingBUSINESS STRATEGY AND THE ENVIRONMENT, Issue 5 2003Abigail Oxley Green Companies now recognise the need to identify and address the concerns of their stakeholders to ensure their decisions and business activities are more socially acceptable. However, despite stakeholder participation being widely accepted in the public sector and used to a limited extent within some business management processes, there is no accepted understanding of what stakeholder participation actually constitutes and certainly no systematic method for its application within companies and company decision-making. In order to support the development of such a method, stakeholder participation must first be defined in the ,company' context. Drawing from previous typologies of participation outlined in the literature, particularly relating to the public sector, this paper proposes a typology of stakeholder participation for companies, with particular relevance to environmental issues. It also outlines the needs and problems associated with developing a method of stakeholder participation for use in company decision-making. Copyright © 2003 John Wiley & Sons, Ltd and ERP Environment. [source] | ||||||||||||||||