bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved multipulse algorithm for speech coding by means of adaptive boltzmann annealing
Authors: Mumolo Enzo , Rebelli Alessio , Riceardi Giuseppe 
Published: January 2011

AbstractIn this paper we will describe an algorithm, based on the Simulated Annealing technique, for solving the problem of multipulse excitation computation for speech coding applications. Multipulse excitation modeling is described by two set of parameters: pulse locations and amplitudes. The search for optimal pulse locations is the most burdensome task, since there is no closed form solution. Therefore, suboptimal approaches are used in order to maintain a good effectiveness in the parameter estimation while keeping the computational load within reasonable bounds. As compared to the one described in [2], the proposed algorithm achieves an effective improvement in objective performances of more than 1.5 dB. The price that must be paid for this performance improvement is the higher computational cost that this algorithm requires. The objective results of the proposed algorithm will be compared with the results of the algorithm described in [2], and the computational complexity will be analyzed.
Hierarchical dynamic control of multiple traffic classes in ATM networks
Authors: Bolla Raffaele , Davoli Franco , Lombardo Alfio , Palazzo Sergio , Panno Daniela 
Published: January 2011

AbstractA hierarchical control structure is proposed to ensure performance requirements and to maintain load balancing among different traffic classes at an ATM node. A two‐level control hierarchy is defined, where one level performs fixed class‐selective call admission control strategies that are periodically dynamically coordinated by a higher level bandwidth allocation controller. The call admission control rules are designed to maintain a certain grade of service, in terms of cell loss probability, given the buffer space and bandwidth (percentage of cells) assigned to each class. The assignment of buffers is performed off‐line, whereas bandwidth shares are periodically recomputed on‐line by the allocation controller, that attempts to minimize a cost function, accounting for overall cell loss and refused traffic. The bandwidth assignments obtained are passed to the call admission controllers, where they are used as parameters affecting the admission rules until the next intervention. The control structure, the strategies and the optimization algorithm used are described in detail, as well as the assumptions underlying the choices that have been made. Simulation results are reported and discussed.
One‐shot pseudo‐time method for aerodynamic shape optimization using the Navier–Stokes equations
Authors: Hazra S. B. , Jameson A. 
Published: January 2011

AbstractThis paper presents a numerical method for aerodynamic shape optimization problems in compressible viscous flow. It is based on simultaneous pseudo‐time stepping in which stationary states are obtained by solving the pseudo‐stationary system of equations representing the state, costate and design equations. The main advantages of this method are that it blends in nicely with previously existing pseudo‐time‐stepping methods for the state and the costate equations, that it requires no additional globalization in the design space, and that a preconditioner can be used for convergence acceleration which stems from the reduced SQP methods. For design examples of 2D problems, the overall cost of computation can be reduced to less than 2 times the forward simulation runs. Copyright © 2011 John Wiley & Sons, Ltd.
A high‐order finite difference method for numerical simulations of supersonic turbulent flows
Authors: Li Zhaorui , Jaberi Farhad A. 
Published: January 2011

AbstractThis paper describes a new class of three‐dimensional finite difference schemes for high‐speed turbulent flows in complex geometries based on the high‐order monotonicity‐preserving (MP) method. Simulations conducted for various 1D, 2D, and 3D problems indicate that the new high‐order MP schemes can preserve sharp changes in the flow variables without spurious oscillations and are able to capture the turbulence at the smallest computed scales. Our results also indicate that the MP method has less numerical dissipation and faster grid convergence than the weighted essentially non‐oscillatory method. However, both of these methods are computationally more demanding than the COMP method and are only used for the inviscid fluxes. To reduce the computational cost for reacting flows, the scalar equations are solved by the COMP method, which is shown to yield similar results to those obtained by the MP in supersonic turbulent flows with strong shock waves. Copyright © 2011 John Wiley & Sons, Ltd.
A numerical study of the wake behind a blunt‐trailing‐edged body. Part 2: the topology of the flow
Authors: Ortega Marcos A. , Girardi Roberto M. , Silvestrini Jorge H. 
Published: January 2011

SUMMARYThis project focuses on the wake behind a two‐dimensional blunt‐trailing‐edged body. The body has an elliptical nose followed by a straight section that ends in a blunt base. For this geometry, the boundary layer separation points are defined and fixed. This permits a better assessment of the vital influence of the boundary layers upon the wake. It is hoped that the study of this special geometry will contribute to a better understanding of the wake flow. The main aim of this article is to study the topology of the wake by means of direct numerical simulation (DNS). The idea is to mimic some experimental work techniques. In an experiment, by means of proper synchronization, one is able to arrive at the mean‐in‐the‐phase fields. In the present work, similar data are obtained through the use of numerical tools. The topology of the wake flow in terms of the movement of the coherent structures, fields of Reynolds stresses, position of saddles and centers, is obtained for certain values of the body's aspect ratio. A comparison with the circular cylinder experimental data is also provided. An important result is the finding of some specific stress distributions around the main structures. The stress level lines are a hint of where the energy transfer of the mean flow to the turbulence is more intense. Copyright © 2011 John Wiley & Sons, Ltd.
Microstructures of phosphatic porcelain from sintering to vitrification: Evidence from sherds excavated in Charleston, South Carolina
Authors: Owen J. Victor , Hunter Robert , Jellicoe Rod , Zierden Martha 
Published: January 2011

AbstractEight phosphatic porcelain sherds recovered from various historical sites in Charleston were analyzed by electron microprobe. Some sherds contain sulfur (2.3–3.1wt.% SO3); others contain only traces of this component. The analytical data suggest that the sulfurous sherds are Bow porcelain (London, Bowcock period, ca. 1755–1769). The origin(s) of the low‐S samples remains unidentified; one compositionally resembles “gold‐anchor period” (phosphatic) Chelsea porcelain (London, ca. 1756–1769) but its decoration is inconsistent with known wares produced by this factory during that era. The degree of vitrification is highly variable, particularly among the SO3‐poor samples. The melt phase is strongly enriched in incompatible elements (Ti, Fe, Na, K). The phosphate phase [calcined bone ash (hydroxyapatite)] in poorly vitrified samples hosts minute melt blebs, but remains porous. With increasing vitrification, these melt blebs increase in size and begin to coalesce, ultimately forming ameboid patches up to ∼10 μm in diameter. In the most vitrified samples, the coalesced melt “leaks” into the matrix, leaving behind a phosphate phase that lacks pores and melt and has a lower CaO/P2O5 ratio (=2.7, molecular proportions) than either hydroxyapatite (3.3) or β‐whitlockite (3.0). The two varieties of phosphate occur in some poorly vitrified samples, suggesting the recycling of high‐fired wasters (as “grog”) in their ceramic pastes. Melt compositions vary with contiguous mineralogy, accounting for their divergence from the ternary eutectic in the Ca3(PO4)2‐CaAl2Si2O8‐SiO2 system. The resorption of phosphate by the matrix melt virtually precludes recognition of anorthite formed by the “non‐phosphate glass equation.” © 2011 Wiley Periodicals, Inc.
Human health care and selection effects. Understanding labor supply in the market for nursing1
Authors: Barigozzi Francesca , Turati Gilberto 
Published: January 2011

SUMMARYThe aim of this paper is to study (adverse) selection in a labor supply model where potential applicants are characterized by different vocational levels and skills. We look at how the composition of the pool of active workers changes as the wage rate increases. Contrary to what would expect, average productivity does not necessarily increase monotonically in the wage rate. We identify conditions in which a wage increase reduces the average productivity and/or average vocation of active workers. Our results help understand the potential impact of wage increases as a policy designed to resolving shortages in the labor market for nurses. Copyright © 2011 John Wiley & Sons, Ltd.
Clinical and pathological determinants in tonsillar cancer
Authors: Chuang Hui‐Ching , Fang Fu‐Min , Huang Chao‐Cheng , Huang Hsuan‐Ying , Chen Han‐Ku , Chen Chang‐Han , Chien Chih‐Yen 
Published: January 2011

AbstractBackgroundThe purpose of this study was to present the impact of clinicopathological factors on patient survival in tonsillar squamous cell carcinoma (SCC) that needs to be evaluated.MethodThis study enrolled 86 patients with tonsillar SCC undergoing surgical resection.ResultsThe cumulative 5‐year disease‐specific survival (DSS) rate for stages I, II, III, and IVa/b tumors was 100%, 91.7%, 100%, and 61.8%, respectively. Unfavorable cumulative 5‐year DSS rates were significantly correlated with advanced T classification (p = .029), tumor thickness over 1 cm (p = .007), 3 or more positive neck lymph nodes (p < .001), and extracapsular spread (ECS; p = .002). Cox regression analysis revealed that the presence of 3 or more positive neck lymph nodes (p = .035) and the stage IVa/b (p = .022) were the independent predictors of the 5‐year DSS.ConclusionPatients with tonsillar SCC with stage IVa/b and metastasis to 3 or more lymph nodes have poorer clinical outcomes. Novel therapeutic strategies are necessary for these patients. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Reirradiation with intensity‐modulated radiotherapy in recurrent head and neck cancer
Authors: Zwicker Felix , Roeder Falk , Hauswald Henrik , Thieke Christian , Timke Carmen , Schlegel Wolfgang , Debus Juergen , Münter Marc W. , Huber Peter E. 
Published: January 2011

AbstractBackgroundIn this retrospective investigation we analyzed outcome and toxicity after intensity‐modulated reirradiation of recurrent head and neck cancer.MethodsThirty‐eight patients with local recurrent head and neck cancer were evaluated. The median dose of initial radiotherapy was 61 Gy. Reirradiation was carried out with step‐and‐shoot intensity‐modulated radiotherapy (median dose: 49 Gy).ResultsMedian overall survival was 17 months, and the 1‐ and 2‐year overall survival rates were 63% and 34%. The 1‐ and 2‐year local control rates were 57% and 53%. Distant spread occurred in 34%, and reirradiation induced considerable late toxicity in 21% of the patients. Thirty‐two percent showed increased xerostomia after reirradiation. The risk for xerostomia was significantly higher for cumulative mean doses of ≥45 Gy to parotid glands. Considering median cumulative maximum doses of 53 Gy to the spinal cord and 63 Gy to the brainstem, no late toxicities were observed.ConclusionsReirradiation with intensity‐modulated radiotherapy in recurrent head and neck cancer is feasible with acceptable toxicity and yields encouraging rates of local control and overall survival. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Epidermal growth factor receptor mutations in patients with oral cavity cancer in a betel nut chewing–prevalent area
Authors: Hsieh Chia‐Hsun , Chang John W. C. , Hsieh Jia‐Juan , Hsu Todd , Huang Shiu‐Feng , Liao Chun‐Ta , Wang Hung‐Ming 
Published: January 2011

AbstractBackgroundEpidermal growth factor receptor (EGFR) mutations exist in patients with oral cavity squamous cell carcinoma (OSCC), but few data about mutation patterns with clinical outcomes were reported.MethodsFifty‐six formalin‐fixed paraffin‐embedded tumor samples were obtained surgically from OSCC patients. Direct sequencing of EGFR was carried out using nested polymerase chain reaction. The relationship between EGFR status and clinical courses was analyzed.ResultsTwo (3.56%) missense mutations (G857R; L862Q) in exon 20 were identified. Two types of silent mutation, A859A in exon 21 (1.79%) and Q787Q mutations in exon 20 (30.36%), were also found. No mutation was detected in exons 18 and 19. No significant difference in disease‐free survival and locoregional control rate was shown between patients with and without Q787Q mutation.ConclusionsWe identified a high frequency of Q787Q mutation and a less prevalent active EGFR mutation in OSCC patients in Taiwan where betel nut is commonly chewed. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Transoral laser microsurgery as primary treatment for advanced‐stage oropharyngeal cancer: A united states multicenter study
Authors: Haughey Bruce H. , Hinni Michael L. , Salassa John R. , Hayden Richard E. , Grant David G. , Rich Jason T. , Milov Simon , Lewis James S. , Krishna Murli 
Published: January 2011

AbstractBackgroundNonsurgical modalities are sometimes advocated as the standard of care for advanced oropharyngeal tumors. Oncologic and functional results have been modest. The aim of our study was to evaluate outcomes of a minimally invasive approach, using transoral laser microsurgery (TLM) as the primary treatment for advanced oropharyngeal carcinoma.MethodsA prospectively assembled database of 204 patients with American Joint Committee on Cancer (AJCC) stages III and IV tonsil or tongue base cancer, treated primarily with TLM during 1996–2006 at 3 centers with minimum 2‐year follow‐up was analyzed. Survival, locoregional control, and swallowing status were recorded.ResultsMean follow‐up was 49 months and 79.4% of patients were alive. Three‐year overall survival, disease‐specific survival, and disease‐free survival were 86%, 88%, and 82%, respectively. Local control was 97%, and 87% of patients had normal swallowing or episodic dysphagia.ConclusionsTLM as a primary treatment for advanced oropharyngeal malignancy confers excellent survival and swallowing proficiency. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Primacy of surgery in the management of mucoepidermoid carcinoma in children
Authors: Ryan Jesse T. , El‐Naggar Adel K. , Huh Winston , Hanna Ehab Y. , Weber Randal S. , Kupferman Michael E. 
Published: January 2011

AbstractBackgroundEpithelial salivary gland neoplasms are rare in children. Malignant tumors account for 30% to 50% of cases in the pediatric age group, with mucoepidermoid carcinoma as the most common histology.MethodsA retrospective medical record review was conducted from 1953 to 2007 to identify patients with mucoepidermoid carcinoma at the age of 18 years or younger at the time of diagnosis. Forty‐nine patients were identified. Their medical records were examined for presentation, treatment, pathologic features, and outcomes.ResultsForty‐nine pediatric patients with mucoepidermoid carcinoma were identified. The parotid gland (49%) and oral cavity (35%) were the most common subsites. Nodal metastasis was seen in 24% of patients. All patients underwent surgery, and 11 patients (22%) were treated with radiation therapy. The 5‐year overall survival was 98%, the 10‐year overall survival was 94%, and 10% of patients developed recurrence.ConclusionMucoepidermoid carcinoma in children carries a favorable prognosis and can be successfully treated with surgery alone in most cases. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
Development of a team workload assessment technique for the main control room of advanced nuclear power plants
Authors: Lin Chiuhsiang Joe , Hsieh Tsung‐Ling , Tsai Ping‐Jung , Yang Chih‐Wei , Yenn Tzu‐Chung 
Published: January 2011

AbstractFor almain control room (MCR) in advanced nuclear power plants (ANPPs), a team of three operators has been adopted to enhance the safety of all the operating conditions, including general, abnormal, and emergent. Therefore, to evaluate the workload of team operators in the MCR of NPPs would be one valuable issues in human factor engineering (HFE) research. The NASA Task Load Index (NASA‐TLX) has been selected to measure the workload of operators in past studies. Some studies, however, indicated that the workload measured by the NASA‐TLX did not have significant correlation with team performance. That is, assessing team workload using NASA‐TLX alone may be a problem, and its sensitivity needs to be verified. In this study, a measurement called Team Workload Assessment (TWA) was developed to evaluate the team workload by characteristics of teamwork. The important characteristics of teamwork, including coordination, communication, support and leadership, and time sharing were developed in the questionnaire. Confirmatory factor analysis and Cronbach's α coefficient were used to examine the validity and reliability of the questionnaire. Finally, the team workload scores of the TWA were compared with the team workload scores of the NASA‐TLX and the task performance was obtained from an experiment designed to verify the suitability of the TWA. As a result, it was found that the team workload scores of the TWA are more sensitive to task performance than are those of the NASA‐TLX. Therefore, the TWA is available to measure the team workload in the MCR of NPPs. © 2011 Wiley Periodicals, Inc.
Modelling hydrological processes influenced by soil, rock and vegetation in a small karst basin of southwest China
Authors: Zhang Zhicai , Chen Xi , Ghadouani Anas , Shi Peng 
Published: January 2011

AbstractHydrological processes in karst basins are controlled by permeable multimedia, consisting of soil pores, epikarst fractures, and underground conduits. Distributed modelling of hydrological dynamics in such heterogeneous hydrogeological conditions is a challenging task. Basing on the multilayer structure of the distributed hydrology‐soil‐vegetation model (DHSVM), a distributed hydrological model for a karst basin was developed by integrating mathematical routings of porous Darcy flow, fissure flow and underground channel flow. Specifically, infiltration and saturated flow movement within epikarst fractures are expressed by the ‘cubic law’ equation which is associated with fractural width, direction, and spacing. A small karst basin located in Guizhou province of southwest China was selected for this hydrological simulation. The model parameters were determined on the basis of field measurement and calibrated against the observed soil moisture contents, vegetation interception, surface runoff, and underground flow discharges from the basin outlet. The results show that due to high permeability of the epikarst zone, a significant amount of surface runoff is only generated after heavy rainfall events during the wet season. Rock exposure and the epikarst zone significantly increase flood discharge and decrease evapotranspiration (ET) loss; the peak flood discharge is directly proportional to the size of the aperture. Distribution of soil moisture content (SMC) primarily depends on topographic variations just after a heavy rainfall, while SMC and actual ET are dominated by land cover after a period of consecutive non‐rainfall days. The new model was able to capture the sharp increase and decrease of the underground streamflow hydrograph, and as such can be used to investigate hydrological effects in such rock features and land covers. Copyright © 2011 John Wiley & Sons, Ltd.
Assessment on the function of reservoirs for flood control during typhoon seasons based on a distributed hydrological model
Authors: Wang Guoqiang , Xu Zongxue 
Published: January 2011

AbstractA grid‐based distributed hydrological model, PDTank model, is used to simulate hydrological processes in the upper Tone River catchment. The Tone River catchment often suffers from heavy rainfall events during the typhoon seasons. The reservoirs located in the catchment play an important role in flood regulation. Through the coupling of the PDTank model and a reservoir module that combines the storage function and operation function, the PDTank model is used for flood forecasting in this study. By comparing the hydrographs simulated using gauging and radar rainfall data, it is found that the spatial variability of rainfall is an important factor for flood simulation and the accuracy of the hydrographs simulated using radar rainfall data is slightly improved. The simulation of the typhoon flood event numbered No. 9 shows that the reservoirs in the catchment attenuate the peak flood discharge by 423·3 m3/s and validates the potential applicability of the distributed hydrological model on the assessment of function of reservoirs for flood control during typhoon seasons. Copyright © 2011 John Wiley & Sons, Ltd.
Some relationships between lithology, basin form and hydrology: a case study from the Thames basin, UK
Authors: Bloomfield J. P. , Bricker S. H. , Newell A. J. 
Published: January 2011

AbstractThe role of lithology in influencing basin form and function is explored empirically by investigating correlations between a range of catchment variables, where the spatial unit of analysis is not surface catchments but lithologically coherent groundwater units. Using the Thames basin, UK, as a case study, nine groundwater units have been identified. Values for 11 hydrological and geomorphological variables, including rainfall, drainage density, Baseflow Index, aquifer porosity, storage coefficient and log‐hydraulic conductivity, aquifer and drainage elevation, river incision, and hypsometric integral have been estimated for each of the groundwater units in the basin, and Pearson correlation coefficients calculated for all pairs of variables. Seven of the correlation coefficients are found to be significant at a confidence level of > 99%. Negative correlations between drainage density and log aquifer hydraulic conductivity, and between drainage density and river incision, and positive correlations between log‐hydraulic conductivity and river incision, log‐hydraulic conductivity and Baseflow Index, and between Baseflow Index and river incision are inferred to have consistent causal explanations. For example, incision of rivers into aquifers leads to relative increases in hydraulic gradients in the vicinity of rivers which, in turn, promotes the development of secondary porosity increasing both aquifer hydraulic conductivity and, hence, Baseflow Index. The implication of this interpretation is that the geomorphological evolution of basins is intimately linked to the evolution of hydraulic conductivity of the underlying aquifers. This is consistent with, and supports the notion of a coupled complexly evolving surface water‐groundwater system. Copyright © 2011 John Wiley & Sons, Ltd.