bluuebunny/crossref_metadata_2025_split huggingface dataset:
OpenACC acceleration of an unstructured CFD solver based on a reconstructed discontinuous Galerkin method for compressible flows
Authors: Xia Yidong , Lou Jialin , Luo Hong , Edwards Jack , Mueller Frank 
Published: February 2015

SummaryAn OpenACC directive‐based graphics processing unit (GPU) parallel scheme is presented for solving the compressible Navier–Stokes equations on 3D hybrid unstructured grids with a third‐order reconstructed discontinuous Galerkin method. The developed scheme requires the minimum code intrusion and algorithm alteration for upgrading a legacy solver with the GPU computing capability at very little extra effort in programming, which leads to a unified and portable code development strategy. A face coloring algorithm is adopted to eliminate the memory contention because of the threading of internal and boundary face integrals. A number of flow problems are presented to verify the implementation of the developed scheme. Timing measurements were obtained by running the resulting GPU code on one Nvidia Tesla K20c GPU card (Nvidia Corporation, Santa Clara, CA, USA) and compared with those obtained by running the equivalent Message Passing Interface (MPI) parallel CPU code on a compute node (consisting of two AMD Opteron 6128 eight‐core CPUs (Advanced Micro Devices, Inc., Sunnyvale, CA, USA)). Speedup factors of up to 24× and 1.6× for the GPU code were achieved with respect to one and 16 CPU cores, respectively. The numerical results indicate that this OpenACC‐based parallel scheme is an effective and extensible approach to port unstructured high‐order CFD solvers to GPU computing. Copyright © 2015 John Wiley & Sons, Ltd.
Contrast enhancement using real coded genetic algorithm based modified histogram equalization for gray scale images
Authors: Babu P. , Rajamani V. 
Published: February 2015

ABSTRACTHistogram equalization is a well‐known technique used for contrast enhancement. The global HE usually results in excessive contrast enhancement because of lack of control on the level of contrast enhancement. A new technique named modified histogram equalization using real coded genetic algorithm (MHERCGA) is aimed to sweep over this drawback. The primary aim of this paper is to obtain an enhanced method which keeps the original brightness. This method incorporates a provision to have a control over the level of contrast enhancement and applicable for all types of image including low contrast MRI brain images. The basic idea of this technique is to partition the input image histogram into two subhistograms based on a threshold which is obtained using Otsu's optimality principle. Then, bicriteria optimization problem is formulated to satisfy the aforementioned requirements. The subhistograms are modified by selecting optimal contrast enhancement parameters. Finally, the union of the modified subhistograms produce a contrast enhanced and details preserved output image. While developing an optimization problem, real coded genetic algorithm is applied to determine the optimal value of contrast enhancement parameters. This mechanism enhances the contrast of the input image better than the existing contemporary HE methods. The quality of the enhanced brain image indicates that the image obtained after this method can be useful for efficient detection of brain cancer in further process like segmentation, classification, etc. The performance of the proposed method is well supported by the contrast enhancement quantitative metrics such as discrete entropy and natural image quality evaluator. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 24–32, 2015
The nonlinear variation regularization algorithm for the magnetic resonance electrical impedance tomography
Authors: Liu Jin‐Zhen , Xiong Hui , Li Gang , Lin Ling 
Published: February 2015

ABSTRACTThe nonlinear variation regularization algorithm (NVRA) is an effective method to enhance the contrast and robustness of the reconstruction in medical imaging. In order to improve the reconstruction quality the variation regularization is introduced to the nonlinear algorithm based on one component of the magnetic flux density by injecting one current. Firstly, we propose a novel algorithm for magnetic resonance electrical impedance tomography (MREIT) using NVRA, and clarify the implementation of this algorithm. Secondly, we analyze the performance of the proposed nonlinear algorithm and the linear sensitivity method with noisy data in the phantom models. Finally, in the case of 0.36 T low field intensity magnetic resonance scanner, we present the method for reducing the electrode model error, and evaluate the performance of two reconstruction algorithms in the agar gel model. The results indicate that the NVRA is able to improve the reconstruction quality with sharp contrast and more robust to noise in comparison to the sensitivity method. In addition, this study shows that with just one current injection and one component of the magnetic flux density we can obtain a high quality imaging, which promotes the MREIT in clinical application. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 68–76, 2015
A rapid automatic brain tumor detection method for MRI images using modified minimum error thresholding technique
Authors: T Kalaiselvi , P Nagaraja 
Published: February 2015

ABSTRACTThis proposed work is aimed to develop a rapid automatic method to detect the brain tumor from T2‐weighted MRI brain images using the principle of modified minimum error thresholding (MET) method. Initially, modified MET method is applied to produce well segmented and sub‐structural clarity for MRI brain images. Further, using FCM clustering the appearance of tumor area is refined. The obtained results are compared with corresponding ground truth images. The quantitative measures of results were compared with the results of those conventional methods using the metrics predictive accuracy (PA), dice coefficient (DC), and processing time. The PA and DC values of the proposed method attained maximum value and processing time is minimum while compared to conventional FCM and k‐means clustering techniques. This proposed method is more efficient and faster than the existing segmentation methods in detecting the tumor region from T2‐weighted MRI brain images. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 77–85, 2015
Universal Enterprise Adaptive Object Model: A Semantic Web‐Based Implementation of Organizational Self‐Awareness
Authors: Aveiro David , Pinto Duarte 
Published: February 2015

SummaryIn this paper we present a novel conceptual model that systematizes the integrated management and adaptation of: (1) enterprise models, (2) their representations, (3) their underlying meta‐models (i.e. their abstract syntax) and (4) the representation rules (i.e. concrete syntax for the respective models). All this for different modelling languages and also different versions of these languages. Thanks to our original use of the adaptive object model and type square patterns—normally applied in the context of software engineering, but here applied for enterprise engineering—we manage to provide a strong conceptual foundation for the development of software tools that allow a precise and coherent specification of models and their evolution and also of meta‐models and their evolution. We also present a prototype of such a tool currently being developed to enable collaborative enterprise ontology model management using the Semantic MediaWiki as a base framework. This solution is solidly grounded on the theoretical foundations of organizational self‐awareness and Ψ‐theory of enterprise ontology and is a valuable contribution to facilitate general and distributed enterprise model management and also concrete and abstract syntax specification (i.e. the specification of a language's meta‐model). This allows flexibility and ease of use in creation and adaptation of organizational models and also the use of semantic queries to detect and inform users on any violation of meta‐model rules. Copyright © 2015 John Wiley & Sons, Ltd.
e‐Textbooks
Authors: Dobler Elizabeth 
Published: February 2015

AbstractThis article explores the digital reading preferences and strategies used by preservice teachers when reading an e‐textbook in a literacy methods course. The use of e‐textbooks is becoming more prevalent due to an increase in access to mobile devices, acceptance of e‐books in general, and the high cost of print textbooks. To ensure comprehension, teachers need an awareness of e‐textbook features and the processes for effectively reading text with embedded web links, video clips, and audio files. In this study, some participants described an increase in cognitive engagement due to the ability to both utilize e‐textbook features and engage with media, in addition to text. Others found the process of reading an e‐textbook challenging because of distractions on their device, eye strain, and a feeling of being overwhelmed with choices. Overall the preservice teachers expressed a preference for choice between using print, electronic format, or both.
Comparison of MALDI‐TOF mass spectra with microsatellite length polymorphisms in Candida albicans
Authors: Dhieb C. , Normand A. C. , L'Ollivier C. , Gautier M. , Vranckx K. , El Euch D. , Chaker E. , Hendrickx M. , Dalle F. , Sadfi N. , Piarroux R. , Ranque S. 
Published: February 2015

Candida albicans is the most frequent yeast involved in human infections. Its population structure can be divided into several genetic clades, some of which have been associated with antifungal susceptibility. Therefore, detecting and monitoring fungal clones in a routine laboratory setting would be a major epidemiological advance. Matrix‐assisted laser desorption/ionization time‐of‐flight (MALDI‐TOF) mass spectra results are now widely used as bar codes to identify microorganisms in clinical microbiology laboratories. This study aimed at testing MALDI‐TOF mass spectra bar codes to identify clades among a set of C. albicans isolates.Accordingly, 102 clinical strains were genotyped using 10 microsatellite markers and analyzed via MALDI‐TOF mass spectrometry. The mass spectra were compared with a reference spectral library including 33 well‐characterized collection strains, using a MicroflexTM system and BiotyperTM software, to test the capacity of the spectrum of a given isolate to match with the reference mass spectrum of an isolate from the same genetic clade.Despite high confidence species identification, the spectra failed to significantly match with the corresponding clade (p = 0.74). This was confirmed with the MALDI‐TOF spectra similarity dendrogram, in which the strains were dispersed irrespective of their genetic clade. Various attempts to improve intra‐clade spectra recognition were unsuccessful.In conclusion, MALDI‐TOF mass spectra bar code analysis failed to reliably recognize genetically related C. albicans isolates. Further studies are warranted to develop alternative MALDI‐TOF mass spectra analytical approaches to identify and monitor C. albicans clades in the routine clinical laboratory. Copyright © 2015 John Wiley & Sons, Ltd.
Characterisation of general proteolytic, milk clotting and antifungal activity of Ficus carica latex during fruit ripening
Authors: Raskovic Brankica , Lazic Jelena , Polovic Natalija 
Published: February 2015

AbstractBACKGROUNDThe physiological role of fig latex is to protect the plant from pathogens. Latex is a rich source of proteases, predominantly ficin. Fig latex also contains collagenolytic protease and chitinolytic enzymes. Our aim was to investigate changes in protein composition, enzyme and antifungal activities of fig latex during fruit ripening.RESULTSComparison of latex samples in different time periods showed a uniform increase of protein concentration in chronological order. The content of collagenolytic protease did not differ significantly in the latex samples, while the content of ficin decreased. Ficin‐specific activity towards casein was the highest at the beginning of fruit development (about 80 U mg−1). Specific milk clotting activity increased as well as the abundance of casein band in the clots. Specific chitinolytic activity at the beginning of flowering was 6.5 times higher than the activity in the period when fruits are ripe. Antifungal activity is the most extensive in spring.CONCLUSIONFicin forms with different casein specificities are present in different proportions during fruit ripening, which is of importance for applications in the dairy industry. The protection mechanism against insects and fungi, which relies on chitinolytic activity, is the most important in the early phases of flowering and is replaced with other strategies over time. © 2015 Society of Chemical Industry
Quadratic and linear controls developing an optimal treatment for the use of BCG immunotherapy in superficial bladder cancer
Authors: Elmouki Ilias , Saadi Smahane 
Published: February 2015

SummaryOur prime objective of the study is to exhibit the advantage to introduce a quadratic control in place of linear control in a cost function to be minimized, and that is associated to an optimal control problem that we formulate for a pre‐validated model of bacillus Calmette‐Guérin (BCG) immunotherapy in superficial bladder cancer. The compartmental model of interest is in the form of a nonlinear system of four ordinary differential equations that describe interactions between the used BCG strain, tumor cells, and immune responses. Previous studies reported that the optimal dose of BCG for treating bladder cancer is yet unknown. Hence, we aim to establish the optimization approach that can be applied for determining the values of the optimal BCG concentration along the therapy period to stimulate immune‐system cells and reduce cancer cells growth during BCG intravesical therapy. Pontryagin's maximum principle and the generalized Legendre–Clebsch condition are employed to provide the explicit formulations of the sought optimal controls. The optimality system is resolved numerically based on a fourth‐order iterative Runge–Kutta progressive‐regressive scheme, which is used to solve a two‐point boundary value problem. Copyright © 2015 John Wiley & Sons, Ltd.
Micro‐Raman spectroscopy as a complementary technique to high resolution X‐ray diffraction for the characterization of Si1‐xGex thin layers
Authors: Durand Aurèle , Rouchon Denis , Le‐Cunff Delphine , Gergaud Patrice 
Published: February 2015

AbstractIn advanced transistor technology, Silicon‐Germanium alloy (SiGe) is being used as a replacement for Si channels to achieve higher mobility. Among the various characterization techniques μ‐Raman spectroscopy is a promising candidate due to a good spatial resolution and low detection threshold. This study presents the evaluation of the technique for the measurement of Ge concentration and comparison to other metrology techniques. As a first step to evaluate the μ‐Raman capability, we considered a simple case of thin SiGe films from 12nm down to 4 nm thickness. Assuming an epitaxial pseudomorphic structure, the Ge content has been extracted for all samples with an average 0.3% stability and at least 1% accuracy as confirmed by high resolution X‐ray diffraction (HRXRD) and secondary ion mass spectrometry analysis (SIMS). We then studied a more complex structure of SiGe on fully depleted‐silicon on insulator (FD‐SOI) as being critical for the development of condensation process of advanced transistor technology. Since μ‐Raman requires prior knowledge of the structural state of the layer, we discuss the interest to combine μ‐Raman measurements with X‐rays diffraction in order to extract the Ge composition on such stacks. μ‐Raman shows a real potential for thin SiGe film characterization and it does not suffers of the lack of precision for very thin films as HRXRD does, however there are still some developments to be made before using it as a metrology technique. Moreover, it could be interesting to couple the technique with HRXRD measurement. The approach to control SiGe condensation process on FD‐SOI might suggest interesting experiment. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Control current stress technique for the investigation of gate dielectrics of MIS devices
Authors: Andreev Vladimir V. , Bondarenko Gennady G. , Maslovsky Vladimir M. , Stolyarov Alexander A. , Andreev Dmitry V. 
Published: February 2015

AbstractIn this study, a modified technique of control current stress to investigation thin gate dielectric of MIS structures is proposed. This technique allows to monitor charge trapping in gate dielectric of MIS structures under high‐field and another stress situations (irradiation, plasma, hot carriers, etc.). The technique also may be used for testing thin gate dielectric defects. Unlike simple techniques, for example constant current stress and J‐ramp current stress, the proposed method uses a sequence of stress current and measuring current pulses. At the same time, the processes of charging and discharging of the MIS structure capacitance as well as the charge trapping in the gate dielectric are taken into account. Charging of MIS structure from inversion to accumulation modes or back way allows one to retrieve a low frequency capacitive‐voltage characteristic. Account charging capacitance of MIS structure and charge trapping in gate dielectric at injective mode lets considerably increase metrological characteristics of this technique and reduce inaccuracies. The models describing the change in the charge state of MIS structures, both in the charge capacity, and in the mode of injection of charge carriers were developed. Using these models let to choose optimal algorithm of current stress and increase measurement accuracy. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Conductance Calculation Of Slot Channels with Variable Cross Section
Authors: Burmistrov A. , Salikeev S. , Bronshtein M. , Fomina M. , Rayko A. 
Published: February 2015

AbstractThe range of operation pressures of non‐contact vacuum pumps may reach six decades, and flow regime in slot channels of the rotor mechanism may vary from molecular flow to viscous flow. This article is a continuation of a series of authors‘ publications dedicated to the development of a method which makes it possible to calculate promptly the conductance of slot channels with complex contoured geometry with the minimal clearance at a certain point along gas flow direction for all three gas flow regimes: molecular, transient and viscous.The numerical solution of the differential equations system (equations of motion, energy, continuity and state) is used for calculation of mass flow rate in transient gas flow regime. On the basis of the numerical calculation results the relationship is obtained which represents a smooth joining of the data for molecular and viscous flow regimes.Verification of the model and the obtained relationship is carried out by comparison of numerical calculation results of gas mass flow rate and conductance with experimental data obtained by blowing‐through of slot channels. The maximal deviation of calculation according to the obtained relationship from the experiment does not exceed 14%, the average uncertainty being less than 8%, which makes it possible to recommend it for practical application in transient flow regime.
Anti‐Eis‐Oberflächenbeschichtungen
Authors: Haupt Michael , Barz Jakob 
Published: February 2015

AbstractEis auf Oberflächen kann die Funktion von Bauteilen erheblich einschränken. Bildes sich Eis auf Flugzeugflügeln kann es im Winter sogar gefährlich werden. Ebenso ist die Eisbildung auf den Rotorblättern von Windenergieanlagen nicht erwünscht. Die Rotorblatter müssen dann beheizt werden um das Eis zu verhindern oder abzuschmelzen. Eis von Oberflächen zu entfernen kostet somit Energie. Das Fraunhofer IGB in Stuttgart hat zusammen mit Partnern eine neuartige Anti‐Eis‐Folie entwickelt, die auf große Flächen einfach aufzukleben ist. Die stoß‐, schlag‐ und kratzfesten Folien werden in einem Niederdruck‐Plasmaprozess funktionalisiert. Diese Folie beeinflusst die Eisbildung und vermindert die Eishaftung auf den Oberflächen erheblich. Mit dieser Folie können verschiedenste Oberflächen beklebt werden und es eröffnet sich ein breites Anwendungsfeld dieser Art von Beschichtung.
Development, Organisation and Implementation of a Surgical Skills ‘Boot Camp’: SIMweek
Authors: Singh Pritam , Aggarwal Rajesh , Pucher Philip H. , Darzi Ara 
Published: February 2015

AbstractBackgroundThere is evidence of increased mortality and reduced efficiency in hospitals due to the annual changeover of junior doctors. This paper describes a framework to develop an intensive simulated week that will recreate experiences and situations that junixor surgical interns will likely face in their first weeks after graduation.MethodsTo provide evidence‐based recommendations, a systematic review of published literature using the keywords ‘surg*’, ‘boot’, ‘camp’ was performed. Reports of the development, implementation or evaluation of a simulated skills course or ‘boot camp’ to prepare incoming surgical interns were analysed.ResultsEighteen relevant articles were identified. Subjects on internship preparation courses have identified ‘hands‐on’ training sessions to be very useful. In particular, mock pages have been identified as being valuable and didactic lectures have been identified as the weakest parts of the course. We first consider the end‐users of the course and their associated learning needs. We subsequently discuss resources required and propose a strategy for the organisation of a course and selection of teaching faculty. Finally, we consider the costs involved in running a course.ConclusionsThis paper proposes a framework for the development, organisation and implementation of an intensive simulation course to prepare graduating medical students for their role as junior surgical intern. Facilitating the step change in responsibility from student to surgical intern may improve patient safety in addition to reducing the associated anxiety for the clinician.
Survival Outcome Between Hepatic Resection and Transarterial Embolization for Hepatocellular Carcinoma More Than 10 cm: A Propensity Score Model
Authors: Chan Yi‐Chia , Kabiling Catherine S. , Pillai Vinod G. , Aguilar Gustavo , Wang Chih‐Chi , Chen Chao‐Long 
Published: February 2015

AbstractBackgroundHepatocellular carcinoma (HCC) larger than ten cm belonging to Barcelona Clinic Liver Cancer (BCLC) stage B and C may benefit from hepatic resection (HR), compared to presently recommended management by transarterial chemoembolization and sorafenib, respectively. This study reviews survival outcomes in such patients treated at a tertiary level hospital in Taiwan, and compares survival advantage of surgical resection over embolization therapy using a statistically valid propensity scores matching model.Methods192 patients newly diagnosed with HCC ≥ 10 cm between 2005 and 2010, who had HR (n = 104) and transarterial embolization (TAE) (n = 88), were retrospectively studied. Thirty‐two patients in each group were selected by propensity scores matching model for comparison.ResultsSurvival rates at 1, 3, and 5 years of patients in BCLC stage B who had HR and TAE were 78.5, 61.4, 54.2 % and 30, 12.9, 12.9 %, (p < 0.001), respectively. For stage C, survival rates were 77.8, 56.4, and 47 % at 1, 3, 5 years in HR group, while it was 12.7 % at 1 year in TAE group, (p < 0.001). Propensity score‐based analysis showed estimated 1‐, 3‐, and 5‐year survival rates of patients receiving HR and TAE were 90.2 versus 26.4 %, 64.3 versus 3.3 %, and 51.5 versus 3.3 %, respectively (p < 0.001).ConclusionsHR had significantly better 5 year survival than TAE for patients with HCC ≥ 10 cm in the propensity score model. Overall survival of BCLC stage B may be improved by considering HR as first treatment option for resectable large HCCs, provided patient is fit for surgery with good liver remnant.