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1 – 10 of 573
Book part
Publication date: 4 August 2008

Stefan Linder

The literature on post-completion reviews (PCRs) either does not deal with the tying of PCRs to extrinsic rewards or provides scant theoretical reasoning or empirical…

Abstract

The literature on post-completion reviews (PCRs) either does not deal with the tying of PCRs to extrinsic rewards or provides scant theoretical reasoning or empirical analysis to back up its recommendations.

Based on research from psychology and empirical studies, the present chapter proposes that several effects of a PCR, which must be deemed rather dysfunctional, will increase when extrinsic rewards are linked to such a review. At the same time some possibly functional effects, however, are likely to remain constant. The propositions, therefore, call the usefulness of tying PCRs to rewards into question and call for further investigation.

Details

Performance Measurement and Management Control: Measuring and Rewarding Performance
Type: Book
ISBN: 978-1-84950-571-0

Article
Publication date: 1 September 2004

TeckLok Wong, Megan Louise Devane, John Andrew Hudson, Paula Scholes, Marion Grace Savill and John D. Klena

This study describes a multiplex polymerase chain reaction (PCR) detection system combined with enrichment growth conditions for simultaneous detection and identification…

1561

Abstract

This study describes a multiplex polymerase chain reaction (PCR) detection system combined with enrichment growth conditions for simultaneous detection and identification of C. jejuni, C. coli and thermotolerant Campylobacter in poultry pack rinses. The PCR primers were tested against a range of Campylobacter and non‐Campylobacter species, and PCR products were only amplified from target organisms. The sensitivity of the method was similar to that obtained by conventional plating procedures, but when used in combination with the MPN method of enumeration could detect levels down to 6 MPN/100 ml of rinse. The validation of 50 samples of chicken pack rinses demonstrated the versatility of this approach in microbiological surveys to yield data for risk assessments.

Details

British Food Journal, vol. 106 no. 9
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 2 March 2010

Salwa Ben Ammou, Zied Kacem and Nabiha Haouas

In this paper, it is set out a hybrid data analysis method based on the combination of wavelet techniques and principal‐components regression (PCR). The purpose of this…

596

Abstract

Purpose

In this paper, it is set out a hybrid data analysis method based on the combination of wavelet techniques and principal‐components regression (PCR). The purpose of this paper is to study the dynamics of the stock returns within the French stock market.

Design/methodology/approach

Wavelet‐based thresholding techniques are applied to the stock price series in order to obtain a set of explanatory variables that are practically noise‐free. The PCR is then carried out on the new set of regressors.

Findings

The empirical results show that the suggested method allows extraction and interpretation of the factors that influence the stock price changes. Moreover, the wavelet‐PCR improves the explanatory power of the regression model as well as its forecasting quality.

Practical implications

The proposed technique offers investors a better understanding of the mechanisms that explain the stock return dynamics as it removes the noise that affects financial time series.

Originality/value

The paper uses a new denoising framework for financial assets. The paper thinks that this framework might be of great value for academics as well as for financial investors.

Details

The Journal of Risk Finance, vol. 11 no. 2
Type: Research Article
ISSN: 1526-5943

Keywords

Article
Publication date: 17 July 2009

E‐Shawn Goh

Cataract surgery is a highly successful, high‐volume surgery, hence reducing surgical complications are imperative for organizations to deliver cost‐effective…

Abstract

Purpose

Cataract surgery is a highly successful, high‐volume surgery, hence reducing surgical complications are imperative for organizations to deliver cost‐effective, high‐quality services that meet the needs of patients. This paper aims to describe 18‐month results of a sustainable program to maximize the safety of cataract surgery training.

Design/methodology/approach

Modifications to the comprehensive cataract‐training program and tested were developed in a controlled, interventional case series to evaluate their effect on trainee complication rates. Data collection and interpretation were performed in a prospective and blind manner.

Findings

Prior to intervention, PCR rates for trainee‐surgeons averaged 3.34 per cent cf international published figures of 4.6‐10 per cent. This compared with 1.89 per cent PCR rate for trained cataract surgeons (p<0.002, Mann Whitney test). Multiple interventions were introduced and enforced to maximize cataract surgery training safety. After 18 months follow‐up data were consistent with a statistically significant reduction in trainee PCR rates (1.53 per cent, p<0.007, Wilcoxon Signed Ranks test) compared with trained cataract surgeons (1.23 per cent, p<0.074, Wilcoxon Signed Ranks test). Parameters of training efficacy were improved or maintained during this period.

Research limitations/implications

Limitations included using trained cataract surgeons as controls as apposed to a similar group of trainee surgeons. In addition, multiple interventions were simultaneously instituted, making identification of a single influential factor impossible to identify.

Practical implications

Maximally safe and effective cataract surgery training is achieved in Singapore without compromising service and quality markers. Similar training goals can be extrapolated to other surgical disciplines.

Originality/value

This is the first study to demonstrate maximally safe and effective cataract surgery training in a large patient group, over sustained periods.

Details

International Journal of Health Care Quality Assurance, vol. 22 no. 5
Type: Research Article
ISSN: 0952-6862

Keywords

Article
Publication date: 15 March 2011

Wu Xuemou

The purpose of this paper is to state new formulation of the programme‐styled framework of pansystems research and related expansions.

Abstract

Purpose

The purpose of this paper is to state new formulation of the programme‐styled framework of pansystems research and related expansions.

Design/methodology/approach

Pansystems‐generalized extremum principle (0**: (dy/dx=0)**) is presented with recognitions to various logoi of philosophy, mathematics, technology, systems, cybernetics, informatics, relativity, biology, society, resource, communications and related topics: logic, history, humanities, aesthetics, journalism, IT, AI, TGBZ* <truth*goodness*beauty*Zen*>, etc. including recent rediscoveries of 50 or so pansystems logoi.

Findings

A keynote of the paper is to develop the deep logoi of the analytic mathematics, analytic mechanics, variational principles, Hilbert's sixth/23rd problems, pan‐axiomatization to encyclopedic principles and various applications. The 0**‐universal connections embody the transfield internet‐styled academic tendency of pansystems exploration.

Originality/value

The paper includes topics: history megawave, pansystems sublation‐modes, pan‐metaphysics, pansystems dialogs with logoi of 100 thinkers or so, and pansystems‐sublation for a series of logoi concerning the substructure of encyclopedic dialogs such as systems, derivative, extremum, quantification, variational principle, equation, symmetry, OR, optimization, approximation, yinyang, combination, normality‐abnormality, framework, modeling, simulation, relativity, recognition, practice, methodology, mathematics, operations and transformations, quotientization, product, clustering, Banach completeness theorem, Weierstrass approximation theorem, Jackson approximation theorem, Taylor theorem, approximation transformation theorems due to Walsh‐Sewell mathematical school, Hilbert problems, Cauchy theorem, theorems of equation stability, function theory, logic, paradox, axiomatization, cybernetics, dialectics, multistep decision, computer, synergy, vitality and the basic logoi for history, ethics, economics, society OR, aesthetics, journalism, institution, resource and traffics, AI, IT, etc.

Details

Kybernetes, vol. 40 no. 1/2
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 9 August 2011

Martin Skote, Gustaf E. Mårtensson and Arne V. Johansson

A precise and rapid temperature cycling of a small volume of fluid is vital for an effective DNA replication process using the polymerase chain reaction (PCR). The purpose…

Abstract

Purpose

A precise and rapid temperature cycling of a small volume of fluid is vital for an effective DNA replication process using the polymerase chain reaction (PCR). The purpose of this paper is to study the velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid.

Design/methodology/approach

The velocity and temperature fields inside a rotating PCR‐tube during cooling of the enclosed liquid are studied. By using computational fluid dynamics, the time development of the flow can be investigated in detail. Owing to the rotation, the flow exhibits features which could never arise in a non‐rotating system.

Findings

An intricate azimuthal boundary layer flow is presented and explained. The inherent problem of stratification of the temperature is discussed, and different methods towards a remedy are presented. By analyzing the governing equations, some properties of the flow observed in the simulations are explained. It is shown that increasing the rate of rotation does not improve temperature homogenization.

Research limitations/implications

The simulations were performed for a limited number of temperature boundary conditions, as well as a specific simulation geometry.

Practical implications

The analytical and simulation results offer fundamental insight into the physics behind increased DNA duplication. Further simulations offer possible design improvements.

Originality/value

While many studies have probed the effects of buoyancy in rotating cylinders and the development of boundary layers in stratified flows in conical containers rotating around their axis of symmetry, little work has been specifically focused on the case where the axis of rotation is normal to the direction of the stratification, which is the case in the present study.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 21 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 August 2000

C.G.J. Schabmueller, A.G.R. Evans, A. Brunnschweiler, G. Ensell, D.L. Leslie and M.A. Lee

Reports the design, fabrication and packaging of a micromachined silicon/Pyrex based chip for the polymerase chain reaction (PCR). The anodic bonding method is used for…

Abstract

Reports the design, fabrication and packaging of a micromachined silicon/Pyrex based chip for the polymerase chain reaction (PCR). The anodic bonding method is used for sealing the chambers of 1μl volume with a Pyrex glass wafer. Platinum resistors on the back of the wafer are used as heaters and temperature sensors. The chip is externally cooled by forced air to achieve rapid temperature cycling. The transparency of the Pyrex makes it possible for using optical readout methods. The packaging is especially designed for easy handling, filling, power connection, temperature regulation and optical readout. The mass production of such silicon reactors could make single‐shot throwaway devices economically viable.

Details

Microelectronics International, vol. 17 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 13 June 2009

G.F. Asensi, E.M.F. dos Reis, E.M. Del Aguila, D. dos P. Rodrigues, J.T. Silva and V.M.F. Paschoalin

This paper seeks to optimize a multiplex PCR in order to detect the incidence of Salmonella and Escherichia coli (E. coli) in chicken carcasses, eliminating a pre‐culture…

1127

Abstract

Purpose

This paper seeks to optimize a multiplex PCR in order to detect the incidence of Salmonella and Escherichia coli (E. coli) in chicken carcasses, eliminating a pre‐culture enrichment step and the pathogen isolation.

Design/methodology/approach

A total of 30 chicken rinse carcasses were analysed by standard microbiological methods, and the isolates were identified by biochemical and serological tests. The results were compared with those obtained by a multiplex PCR using validated primers targeting for invA and lamB genes of Salmonella and E. coli, respectively.

Findings

Microbiological analysis showed the prevalence of Salmonella in 14 out of 30 chicken carcasses. The same rinse samples were also analysed by multiplex PCR, which allowed the simultaneous detection of both bacteria directly from the chicken rinse water microbial community.

Originality/value

The optimized mPCR detected enterobacteria directly from the rinse samples, a complex matrix food, in one workday. There was 100 per cent agreement of the conventional microbiological analysis with those results obtained by multiplex PCR.

Details

British Food Journal, vol. 111 no. 6
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 6 April 2010

Wen‐Tsao Pan

The purpose of this paper is to propose an analysis method based on a hybrid model, which combines principal component regression (PCR) model and general regression neural…

1538

Abstract

Purpose

The purpose of this paper is to propose an analysis method based on a hybrid model, which combines principal component regression (PCR) model and general regression neural network (GRNN) to solve both multicollinearity problems and non‐linear problems at the same time.

Design/methodology/approach

First, the financial ratio data of companies with stocks listed in regular stock market and over‐the‐counter stock market in Taiwan and Mainland China are collected and used as sample data. Grey relational analysis is used to rank the enterprises' operation performance, and the enterprises in Taiwan and Mainland China with business operation performance in the first place are selected and their stock information collected to perform the prediction of stock closing price.

Findings

Five indices such as the root mean square error, revision Theil inequality coefficient, mean absolute error, mean absolute percentage error and coefficient of efficiency of the test result are calculated; the empirical results show that the prediction power of the hybrid model of PCR+genetic algorithm general regression neural network is obviously better than the model of PCR, GRNN and PCR+GRNN.

Originality/value

The paper adopts a hybrid model and parameter adjustment to increase prediction capability.

Details

Chinese Management Studies, vol. 4 no. 1
Type: Research Article
ISSN: 1750-614X

Keywords

Article
Publication date: 19 August 2019

Bo Xiong, Sidney Newton, Vera Li, Martin Skitmore and Bo Xia

The purpose of this paper is to present an approach to address the overfitting and collinearity problems that frequently occur in predictive cost estimating models for…

Abstract

Purpose

The purpose of this paper is to present an approach to address the overfitting and collinearity problems that frequently occur in predictive cost estimating models for construction practice. A case study, modeling the cost of preliminaries is proposed to test the robustness of this approach.

Design/methodology/approach

A hybrid approach is developed based on the Akaike information criterion (AIC) and principal component regression (PCR). Cost information for a sample of 204 UK school building projects is collected involving elemental items, contingencies (risk) and the contractors’ preliminaries. An application to estimate the cost of preliminaries for construction projects demonstrates the method and tests its effectiveness in comparison with such competing models as: alternative regression models, three artificial neural network data mining techniques, case-based reasoning and support vector machines.

Findings

The experimental results show that the AIC–PCR approach provides a good predictive accuracy compared with the alternatives used, and is a promising alternative to avoid overfitting and collinearity.

Originality/value

This is the first time an approach integrating the AIC and PCR has been developed to offer an improvement on existing methods for estimating construction project Preliminaries. The hybrid approach not only reduces the risk of overfitting and collinearity, but also results in better predictability compared with the commonly used stepwise regression.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 10
Type: Research Article
ISSN: 0969-9988

Keywords

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