bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using feedforward neural networks and forward selection of input variables for an ergonomics data classification problem
Authors: Chen Chuen‐Lung , Kaber David B. , Dempsey Patrick G. 
Published: December 2003

AbstractA method was developed to accurately predict the risk of injuries in industrial jobs based on datasets not meeting the assumptions of parametric statistical tools, or being incomplete. Previous research used a backward‐elimination process for feedforward neural network (FNN) input variable selection. Simulated annealing (SA) was used as a local search method in conjunction with a conjugate‐gradient algorithm to develop an FNN. This article presents an incremental step in the use of FNNs for ergonomics analyses, specifically the use of forward selection of input variables. Advantages to this approach include enhancing the effectiveness of the use of neural networks when observations are missing from ergonomics datasets, and preventing overspecification or overfitting of an FNN to training data. Classification performance across two methods involving the use of SA combined with either forward selection or backward elimination of input variables was comparable for complete datasets, and the forward‐selection approach produced results superior to previously used methods of FNN development, including the error back‐propagation algorithm, when dealing with incomplete data. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 31–49, 2004.
Improving performance and quality of working life: A model for organizational health assessment in emerging enterprises
Authors: Shoaf Christin , Genaidy Ash , Karwowski Waldemar , Huang Samuel H. 
Published: December 2003

AbstractThe organization of work has been addressed through numerous perspectives by a diverse set of disciplines. While job stress research has focused on the promotion of worker well‐being, contemporary business‐improvement initiatives (e.g., lean manufacturing, six sigma) have sought to optimize effectiveness through work processes. However, these two aims, although traditionally viewed as contradictory, are actually interdependent variables in the determination of long‐term profitability. The concept of organizational health blends the pursuit of individual wellness with organizational effectiveness to yield a strategy for economic resilience. This article introduces a novel model for organizational health assessment using a systemic approach that addresses work factors at the individual, job, process, and organizational levels. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 81–95, 2004.
Relationship between platinum wire temperature and catalytic heat release rate on platinum in unsteady‐state hydrogen–air mixture
Authors: Nakamura Daisuke , Nagata Harunori , Totani Tsuyoshi , Kudo Isao 
Published: December 2003

AbstractThe authors have proposed a hydrogen concentration probe using a catalytic reaction on the surface of a platinum wire. To use this probe for detecting the concentration change in a supersonic mixing layer, the response of the catalytic heat release rate must depend only on the change of concentration around the probe. The catalytic heat release rate on the surface of the platinum wire in an unsteady state was measured by a constant‐temperature hot‐wire anemometer and a shock tube to investigate the relationship between the response of the catalytic heat release rate and the temperature of the platinum wire. The catalytic heat release rate began increasing upon the introduction of the shock wave. The rate of increase of catalytic heat release depended on the temperature of the platinum wire when the temperature of the hot wire was low. However, the dependence was very weak when the temperature of the hot wire was above 400°C. This shows that it is not the catalytic reaction but rather molecular transfer from the flow to the surface of the platinum wire is the controlling step when the temperature of the platinum wire is high. In conclusion, the temperature of the platinum wire must be above 400°C to use the hydrogen concentration probe in a supersonic mixing layer. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 1–11, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10129
A simple method for predicting the performance of a heat exchanger mounted in an air conditioner (1st report, proposed reduced‐mesh analysis modeling method)
Authors: Kudoh Mitsuo , Sasaki Shigeyuki , Hatada Toshio , Morimoto Motoo 
Published: December 2003

AbstractTo analyze the performance of a heat exchanger (HEX) used in air conditioners within a realistic time frame, a simple method—based on a reduced‐mesh calculation model—was developed. The pressure loss caused by the HEX is given by a momentum source term, and the heat‐transfer performance of the HEX is approximated by using a wall function as the boundary condition. The analytical results from this simple analysis model (under a fin‐pitch range of 1.0 to 1.6 mm) were compared with experimental measurements of pressure loss and heat‐transfer performance. This comparison showed that the pressure loss from the simple analysis model agrees with the experimentally measured loss (within 3% error) and that the heating capacity determined by the simple model agrees with the experimentally measured one (within a 1% error). © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 12–23, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10130
Experimental study on flow characteristics of a sleeved jet into a main crossflow
Authors: Wu H.L. , Chen T.K. , Luo Y.S. , Gong W.Q. 
Published: December 2003

AbstractExperiments were carried out on the hydraulic mechanism of the thermal shock caused by cold jet injection at a T‐junction with thermal sleeve in the reactor cooling system using digital particle imaging velocimetry (DPIV) technique to measure the flow in the main duct and in the annular space of the sleeve tube. The flow and vorticity characteristics were investigated at jet‐to‐crossflow velocity ratios of 0.5 to 4. There was a stream of discharge from the annular space at the rear part of the sleeve near the jet exit, which resulted in decreasing the influence of the jet on the downstream wall. The intensive vorticity in the near wake mainly originated from the shear layer vorticity of the jet and the annular discharge stream. The intensive vorticity soon broke down and dissipated, and further developed into the counterrotating vortex pair in the far wake. The flow in the annulus was closely dependent on R, and thermal protection of the sleeve would become evident at higher R. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 24–31, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10131
Numerical simulation of high‐temperature phase change heat storage system
Authors: Xing Yu‐Ming , Xu Xin , Yuan Xiu‐gan , Cui Hai‐Ting , Zhang Yun‐hao 
Published: December 2003

AbstractIn this paper, numerical results pertaining to cyclic melting and freezing of an encapsulated phase‐change material (PCM) have been reported. The cyclic nature of the present problem is relevant to latent heat thermal energy storage system used to power solar Brayton engines in space. In particular, a physical and numerical model of the single‐tube phase change heat storage system was developed. A high‐temperature eutectic mixture of LiF‐CaF2 was used as the PCM and dry air was used as the working fluid. Numerical results were compared with available experimental data. The trends were in close agreement. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 32–41, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10132
Design of miniature loop heat pipe
Authors: Chu C.I. , Wu S.C. , Chen P.L. , Chen Y.M. 
Published: December 2003

AbstractIn the present study, the loop heat pipe (LHP) was miniaturized for application to electronic cooling. According to the capillary limitation, the wick structure parameters that would affect the heat transfer capacity were analyzed theoretically. Among the various wick parameters, this study especially investigated the effect of wick thickness, which has rarely been mentioned in the literature. Here, various thicknesses were analyzed theoretically and then tested experimentally. The results showed that the temperature on the evaporator wall dropped with decreasing wick thickness. This effect would lead to the raising of heat transfer capacity and the descending of thermal resistance. According to the analysis and the practical demand for electronic cooling, a miniature LHP was fabricated with the evaporator outer diameter of 13 mm and the evaporator length of 50 mm. The testing results showed that, at the allowable working temperature of 80 °C, the maximum heat transfer capacity was up to 200 W and the thermal resistance was 0.17 °C/W. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 42–52, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10133
Numerical simulation of coupled radiation‐convection heat transfer of high‐temperature developing flow in tube
Authors: Xia Xin‐Lin , Zhang Hao‐Chun , Tan He‐Ping , Ma Guo‐Song 
Published: December 2003

AbstractBy combining the discrete ordinate method with the control volume method, the coupled radiation‐convection heat transfer of high‐temperature developing laminar flow in a tube is investigated numerically. The radiative transfer is solved by the discrete ordinate method and its contribution to thermal balance is dealt with as a source term in the energy equation, which is solved, as well as the momentum equation, by the control volume method. The effects of medium optical thickness and tube wall temperature on the temperature distribution in medium as well as the heat flux and local Nusselt number on wall are analyzed. The results show that the radiation heat transfer of high‐temperature medium influences the temperature distribution and convection heat transfer greatly, and plays an important role in the heat transfer of developing laminar flow in a tube. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 53–63, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10135
Coupled radiation‐convection heat transfer of high‐temperature participating medium in heated/cooled tubes
Authors: Xia Xin‐Lin , Huang Yong , Tan He‐Ping , Ren De‐Peng 
Published: December 2003

AbstractThe coupled radiation‐convection heat transfer of high‐temperature participating medium in heated/cooled tubes is investigated numerically. The medium flows in a laminar and fully developed state with a Poiseuille velocity distribution, but the thermal status is developing. By the discrete ordinate method, the nonlinear integrodifferential radiative transfer equation in a cylindrical coordinate form is solved to give the radiative source term in the energy equation of coupled heat transfer. The energy equation is solved by the control volume method. The local Nusselt number and wall heat flux of convection as well as the total wall heat flux are employed to evaluate the influence of radiation heat transfer on convection. The analysis shows that the radiation heat transfer weakens the convection effect, promotes the temperature development, and significantly shortens the tube length with obvious heated/cooled effect. There is an obvious difference between the coupled heat transfer in a heated tube and that in a cooled tube, even though the medium properties are kept constant. The wall emissivity, the medium thermal conductivity and scattering albedo have significant influences on the coupled heat transfer, but the effect of medium scattering phase function is small. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(1): 64–72, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.10137
Year‐round observations of the energy and water vapour fluxes above a boreal black spruce forest
Authors: Arain M. A. , Black T. A. , Barr A. G. , Griffis T. J. , Morgenstern K. , Nesic Z. 
Published: December 2003

AbstractFluxes of energy and water vapour were measured continuously over an ∼120‐year‐old black spruce (Picea mariana (Mill.) B.S.P.) forest in northern Saskatchewan, Canada, from 6 May 1999 to 5 May 2001 using the eddy covariance technique as part of the Boreal Ecosystem Research and Monitoring Sites (BERMS) program. These results demonstrate that long‐term eddy covariance fluxes can reliably be measured during the harsh boreal winter. Typical daytime bulk surface conductance values were about 5–8 mm s−1 during the growing season. Surface conductance sharply declined after midday in response to increasing vapour pressure deficit. The monthly mean values of energy balance components showed that, in spring (March–June), partitioning of available energy flux was mainly in the form of sensible heat, which changed to almost equal proportions of sensible and latent heat in the summer (July–October). In winter (November–February), most of the net radiation was balanced by sensible heat flux. The monthly mean values of net radiation, sensible heat and latent heat flux were about −20 to 20 W m−2, −10 to 25 W m−2 and 5 to 10 W m−2 respectively in winter. The average mid‐day Bowen ratios were approximately 3·5, 1·7 and 5·2 in the spring, summer and winter seasons respectively. The maximum daily evaporation was about 3·5 mm day−1 in summer and 0·1–0·25 mm day−1 in winter. Over the 2 year period, the accumulated precipitation was 835 mm; this compared with 711 ± 70 mm of evapotranspiration, which showed that more than 85% of water was returned to the atmosphere through evapotranspiration. This study reports the first complete annual cycles of energy and water vapour fluxes at this black spruce site. Since black spruce is the dominant tree species in the North American boreal forest, these results have significance for regional and global energy and water cycles. Copyright © 2003 Crown in the right of Canada. Published by John Wiley & Sons, Ltd.
Spring flood analysis using the flood‐duration–frequency approach: application to the provinces of Quebec and Ontario, Canada
Authors: Javelle Pierre , Ouarda Taha B. M. J. , Bobée Bernard 
Published: December 2003

AbstractMost often, flood frequency analysis describes a flood event only by its peak. However, the true flood severity is also defined by its volume and duration. This paper presents an approach allowing flood events to be considered in a more complete way: the flood‐duration–frequency (QdF) approach. In a similar manner to the rainfall intensity–duration–frequency analysis, averaged discharges are computed over differentfixeddurationsd. For each duration a frequency distribution of maximum averaged discharges is studied. Finally, a continuous formulation is fitted, as a function of the return periodTand the durationdover which discharges have been averaged. The proposed model has been tested for 169 catchments in the provinces of Quebec and Ontario, Canada. The shapes of the QdF curves enabled us to define different types of flood behaviour and to identify the corresponding geographic regions. This mapping of flood behaviour was the basis for the delineation of seven homogeneous geographical regions, containing catchments having the same hydrological behaviour as is required for regional flood frequency analysis. Copyright © 2003 John Wiley & Sons, Ltd.
Assessment of the impact of meteorological network density on the estimation of basin precipitation and runoff: a case study
Authors: St‐Hilaire André , Ouarda Taha B. M. J. , Lachance Marius , Bobée Bernard , Gaudet Jocelyn , Gignac Claude 
Published: December 2003

AbstractIn recent years in North America, a number of government agencies and industries have begun to reinvest in meteorological networks. This investment must be based on sound scientific advice. Increased meteorological station network density can be beneficial for a number of purposes, including flood forecasting. This study aimed at investigating the impact of network density at two temporal scales, i.e. for the estimation of total annual precipitation and for the estimation of daily precipitation during specific rain events. This was done using kriging as a means to estimate the spatial distribution and variance of rainfall. Kriged precipitation from two network scenarios (sparse and dense) were used as input into the HSAMI hydrological model and simulations were compared on five drainage basins in the Mauricie area (Québec, Canada).A comparison of the distribution of total annual precipitation interpolated from the two network scenarios showed that adding stations changed the distribution and magnitude of rainfall in the study area. High precipitation cells were better defined with the denser network, and decreases in the relative spatial variance were observed. Similarly, kriged daily precipitation provided a more defined spatial distribution of rainfall during important rain events of 1999, and variance was also reduced when the denser network was used.Finally, simulations performed with the HSAMI model were generally improved when the precipitation inputs were estimated using a denser station network for most drainage basins studied, as expressed by increased Nash coefficients and a decreased root‐mean‐square error. Peak flows during important summer flood events were generally better simulated when a denser network was used to calculate the mean daily precipitation used as input. Total cumulated volume estimations during the rain events were also generally improved with a denser network.This study showed that the estimation of variance remains an important tool for rain gauge network design. Moreover, network density was shown to have an important impact on the quality of flow simulations, even when a lumped model is used. Copyright © 2003 John Wiley & Sons, Ltd.
An analysis of the ground‐penetrating radar direct ground wave method for soil water content measurement
Authors: Galagedara L. W. , Parkin G. W. , Redman J. D. 
Published: December 2003

AbstractThe spatial variability of soil water content can be measured with the ground wave velocity of ground‐penetrating radar (GPR) using short antenna offsets, but picking the correct ground wave arrival time is rather difficult. In applying the GPR ground wave method to soil water content estimation it is also important to know the effective sampling depth of the method. Uniform drainage experiments were conducted with 100 and 450 MHz GPR antennas using 1·0 and 2·0 m fixed antenna separations on a sandy loam soil to investigate time zero picking methodologies and to estimate the sampling depth of the GPR method. The GPR water content data were compared with time‐domain reflectometry (TDR)‐measured data using six vertical TDR probes of different lengths. Time zero was calculated from an air calibration at a 2·0 m antenna separation and from wide‐angle reflection and refraction data, and a difference was found between the two time‐zero calibration methods. A method was analysed to determine the arrival time of the leading edge of the direct ground wavelet using the arrival time of the peak amplitude, since the arrival time of the leading edge of the ground wave can be difficult to pick. Regression analysis showed that the GPR (100 MHz) measured water content was not different from the water content measured with TDR at 0–0·1 m depth, implying that this may be a reasonable estimate of the GPR ground wave method's sampling depth. A similar analysis based on the differences between the 0–0·2 m TDR and the GPR shows that the effective sampling depth of the direct ground wave of the 450 MHz data is less than the sampling depth of the 100 MHz data. Copyright © 2003 John Wiley & Sons, Ltd.
Topographic parameterization in continental hydrology: a study in scale
Authors: Armstrong Robert N. , Martz Lawrence W. 
Published: December 2003

AbstractDigital elevation models (DEMs) are useful and popular tools from which topographic parameters can be quickly and efficiently extracted for various hydrologic applications. DEMs coupled with automated methods for extracting topographic information provide a powerful means of parameterizing hydrologic models over a wide range of scales. However, choosing appropriate DEM scales for particular hydrologic modelling applications is limited by a lack of understanding of the effects of scale and grid resolution on land‐surface representation. The scale effects of aggregation on square‐grid DEMs of two continental‐scale basins are examined. Base DEMs of the Mackenzie and Missouri River basins are extracted from the HYDRO1k DEM of North America. Successively coarser grids of 2, 4, 8, … 64 km were generated from the ‘base’ DEMs using simple linear averaging. TOPAZ (Topographic Parameterization) was applied to the base and aggregated DEMs using constant critical source area and minimum source channel length values to extract topographic variables at varying scales or resolutions. The effects of changing DEM resolution are examined by considering changes in the spatial distribution and statistical properties of selected topographic variables of hydrological importance. The effects of increasing grid size on basin and drainage network delineation, and derived topographic variables, tends to be non‐linear. In particular, changes in overall basin extent and drainage network configuration make it impractical to apply a simple scaling function to estimate variable values for fine‐resolution DEMs from those derived from coarse‐resolution DEMs. Results also suggest the resolution to which a DEM can be reduced by aggregation and still provide useful topographic information for continental‐scale hydrologic modelling is that at which the mean hydraulic slope falls to approximately 1%. In this study, that generally occurred at a resolution of about 10 km. Copyright © 2003 John Wiley & Sons, Ltd.
Detection of trends in annual extreme rainfall
Authors: Adamowski Kaz , Bougadis John 
Published: December 2003

AbstractInformation on intensity–duration–frequency of rainfall is commonly required for a variety of hydrologic applications. In this study, trends are estimated for different durations of annual extreme rainfall using the regional average Mann–Kendall S trend test. The method of L‐moments was employed to delineate homogeneous regions. The trend test was modified to account for observed autocorrelation, and a bootstrap methodology was used to account for the observed spatial correlation.Numerical analysis was performed on 44 rainfall stations from the province of Ontario, Canada, for a 20 year time frame. This was done using data from homogeneous regions established using the L‐moments procedure for the annual maximum observations for the following durations: 5, 10, 15 and 30 min, and 1, 2, 6 and 12 h. Depending on different rainfall durations, four or five homogeneous regions were delineated.Based on a 5% significance level, approximately 23% of the regions tested had a significant trend, predominantly for short‐duration storms. Serial dependency was observed in 2·3% of data sets and spatial correlation was found in 18% of the regions. The presence of serial and spatial correlation had a significant impact on trend determination. Copyright © 2003 John Wiley & Sons, Ltd.