检索结果-南通市图书馆

ON THE MONTE carlo SIMULATION Of NORMAL GRAIN GROWTH

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2008年第4期21卷 282-288页

作者： Y.T. Liu X.J. Guan X.M. Shen X.f. Ma L.J. Wang School of Materials Science and Engineering Shandong University Jinan 250061 China

The microstructures and their kinetics of normal grain growth are simulated using different Monte carlo （MC） algorithms. Compared with the relative figures and the theoretical normal grain growth exponents of n =0.5, the effects of some factors of MC algorithm, i.e. the lattice types, the methods of selecting lattice sites, and the neighbors selection for energy calculations, on the simulation results of grain growth are studied. Two methods of regression were compared, and the three-parameter nonlinear regression is much more suitable for fitting the grain growth kinetics. A better model with appropriate factors included triangular lattice, the attempted site randomly selected, and the first and second nearest neighbors for energy calculations is obtained.

关键词： Grain growth Microstructure Monte carlo method Computer simulation Grain growth kinetics Nonlinear regression

Status and accuracy of the Monte carlo generators for luminosity measurements

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 883-888页

作者： G.Montagna G.Balossini C.Bignamini C.M.carloni Calame O.Nicrosini f.Piccinini Dipartimento di fisica Nucleare e Teorica Università di Pavia Istituto Nazionale di fisica Nucleare School of Physics & Astronomy University of Southampton

The status and accuracy of the precision Monte carlo generators used for luminosity measurements at flavour factories is reviewed. It is shown that, thanks to a considerable, long-term effort in tuned comparisons between the predictions of independent programs, as well as in the validation of the generators against the presently available calculations of the next-to-next-to-leading order QED corrections to Bhabha scattering, the theoretical accuracy reached by the most precise tools is of about one per mille. This error estimate is valid for realistic experimental cuts, appears to be quite robust and is already sufficient for very accurate luminosity measurements. However, recent progress and possible advances to further improve it are also discussed.

关键词： Luminosity QED Bhabha scattering radiative corrections Monte carlo NNLO calculations

Entropy Bayesian Analysis for the Generalized Inverse Exponential Distribution Based on URRSS

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第12期69卷 3795-3811页

作者： Amer I.Al-Omari Amal S.Hassan Heba f.Nagy Ayed R.A.Al-Anzi Loai Alzoubi faculty of Science Department of MathematicsAl al-Bayt UniversityMafraq25113Jordan faculty of Graduate Studies for Statistical Research Cairo UniversityGiza12613Egypt Department of Mathematics College of Science and Human Studies at Hotat SudairMajmaah UniversityMajmaah11952Saudia Arabia

This paper deals with the Bayesian estimation of Shannon entropy for the generalized inverse exponential *** that the observed samples are taken from the upper record ranked set sampling(URRSS)and upper record values(URV)*** of Bayesian estimators are derived depending on a gamma prior distribution considering the squared error,linear exponential and precautionary loss functions,in addition,we obtain Bayesian credible *** random-walk Metropolis-Hastings algorithm is handled to generate Markov chain Monte carlo samples from the posterior ***,the behavior of the estimates is examined at various record *** output of the study shows that the entropy Bayesian estimates under URRSS are more convenient than the other estimates under URV in the majority of the ***,the entropy Bayesian estimates perform well as the number of records *** obtained results validate the usefulness and efficiency of the URV *** data is analyzed for more clarifying purposes which validate the theoretical results.

关键词： Shannon entropy generalized inverse exponential distribution Bayesian estimators loss function ranked set sampling markov chain

Laparoscopic surgery for rectal cancer:The state of the art

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Surgery 2010年第9期2卷 275-282页

作者： carlo Staudacher Andrea Vignali Department of Surgery IRCCS San RaffaeleUniversity Vita-SaluteVia Olgettina 6020132 MilanItaly

At present time,there is evidence from randomized controlled studies of the success of laparoscopic resection for the treatment of colon cancer with reported smaller incisions,lower morbidity rate and earlier recovery compared to open *** limitations and a steep learning curve have limited the wide application of miniinvasive surgery for rectal *** present article discusses the current status of laparoscopic resection for rectal cancer.A review of the more recent retrospective,prospective and randomized controlled trial(RCT) data on laparoscopic resection of rectal cancer including the role of trans-anal endoscopic microsurgery and robotics was performed.A particular emphasis was dedicated to mid and low rectal *** prospective and RCT trials specif ically addressing laparoscopic rectal cancer resection are currently available in the *** short-term outcomes in term of lesser intraoperative blood loss,reduced analgesic requirements and a shorter hospital stay have been *** have recently been raised in the largest RCT trial of the oncological adequacy of laparoscopy in terms of increased rate of circumferential *** data however was not conf irmed by other prospective comparative ***,a similar local recurrence rate has been reported in RCT and comparative *** f indings of overall and disease free survival have been reported but the follow-up time period is too short in all these studies and the few RCT trials currently available do not draw any def initive *** the basis of available data in the literature,the mini-invasive approach to rectal cancer surgery has some short-term advantages and does not seem to confer any disadvantage in term of local *** respect to longterm survival,a definitive answer cannot be given at present time as the results of RCT trials focused on long-term survival currently ongoing are still to fully clarify this issue.

关键词： Postoperative complications Recurrence rate Transanal endoscopic microsurgery Robotics Long-term outcome Prognosis Rectal cancer Laparoscopy

Performance of liver stiffness measurements by transient elastography in chronic hepatitis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第1期19卷 49-56页

作者： Giovanna ferraioli Carmine Tinelli Barbara Dal Bello Mabel Zicchetti Raffaella Lissandrin Gaetano filice carlo filice Elisabetta Above Giorgio Barbarini Enrico Brunetti Willy Calderon Marta Di Gregorio Roberto Gulminetti Paolo Lanzarini Serena Ludovisi Laura Maiocchi Antonello Malfitano Giuseppe Michelone Lorenzo Minoli Mario Mondelli Stefano Novati Savino fA Patruno Alessandro Perretti Gianluigi Poma Paolo Sacchi Domenico Zanaboni Marco Zaramella Ultrasound Unit Department of Infectious DiseasesFondazione IRCCS Policlinico San MatteoMedical School University of Pavia27100 PaviaItaly Clinical Epidemiology and Biometric Unit Fondazione IRCCS Policlinico San Matteo27100 PaviaItaly Department of Pathology Fondazione IRCCS Policlinico San Matteo27100 PaviaItaly Department of Infectious Diseases Fondazione IRCCS Policlinico San MatteoMedical School University of Pavia27100 PaviaItaly Department of Infectious Diseases Fondazione IRCCS Policlinico San Matteo27100 PaviaItaly

AIM:To compare results of liver stiffness measurements by transient elastography(TE) obtained in our patients population with that used in a recently published ***:This was a single center cross-sectional *** patients with chronic viral hepatitis scheduled for liver biopsy at the outpatient ward of our Infectious Diseases Department were *** was carried out by using fibroScan(Echosens,Paris,france).Liver biopsy was performed on the same day as TE,as day case *** was staged according to the Metavir scoring *** diagnostic performance of TE was assessed by using receiver operating characteristic(ROC) curves and the area under the ROC curve ***:Two hundred and fifty-two patients met the inclusion ***(2%) patients were excluded due to unreliable TE ***,246(171 men and 75 women) patients were *** hundred and ninety-five(79.3%) patients had chronic hepatitis C,41(16.7%) had chronic hepatitis B,and 10(4.0%) were coinfected with human immunodeficiency *** curve analysis identified optimal cut-off value of TE as high as 6.9 kPa forf ≥ 2;7.9 kPa forf ≥ 3;9.6 kPa for f = 4 in all patients(n = 246),and as high as 6.9 kPa for f ≥ 2;7.3 kPa for f ≥ 3;9.3 kPa for f = 4 in patients with hepatitis C(n = 195).Cut-off values of TE obtained by maximizing only the specificity were as high as 6.9 kPa for f ≥ 2;9.6 kPa for f ≥ 3;12.2 kPa for f = 4 in all patients(n = 246),and as high as 7.0 kPa forf ≥ 2;9.3 kPa forf ≥ 3;12.3 kPa forf = 4 in patients with hepatitis C(n = 195).CONCLUSION:The cut-off values of TE obtained in this single center study are comparable to that obtained in a recently published meta-analysis that included up to 40 studies.

关键词： Chronic viral hepatitis Hepatitis C Liver Liver biopsy Liver fibrosis Elastography Transient elastography fibroScan Ultrasound

Estimation and Prediction for flexible Weibull Distribution Based on Progressive Type II Censored Data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Mathematics and Statistics 2020年第3期8卷 255-277页

作者： O.M.Bdair R.R.Abu Awwad G.K.Abufoudeh M.f.M.Naser faculty of Engineering Technology Al-Balqa Applied UniversityAmmanJordan Department of Mathematics Faculty of Arts and SciencesUniversity of PetraAmmanJordan

In this work,we consider the problem of estimating the parameters and predicting the unobserved or removed ordered data for the progressive type II censored flexible Weibull *** and Bayesian analyses are adopted for conducting the estimation and prediction *** likelihood method as well as the Bayesian sampling techniques is applied for the inference *** point predictors and credible intervals of unobserved data based on an informative set of data are *** ChainMonte carlo samples are performed to compare the so-obtained methods,and one real data set is analyzed for illustrative purposes.

关键词： flexible Weibull distribution Progressive censoring data Bayes estimation Bayes prediction Gibbs sampling Simulation

User‘s friendly Interface to the CDf Data Handling System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Conference on Computing in High Energy and Nuclear Physics 2001年第1期 294-295页

作者： f.Ratnikov Rutgers TheStateUniversityofNJUSA

The CDf collaboration at the fermilab Tevatron analyses proton-antiproton interactions at a center-of=mass energy of 2 *** the the collider run starting this year the experiment expects to record 1 Petabyte of data and associated data samples,The Data Handling(DH) system has online and offline *** DH offline component provides access to the stored data,to stored reconstruction output,to stored Monte-carlo data samples,and user owned data *** serves more than 450 physicists of the *** extra requirements to the offline component of the Data Handling system are simplicity and convenience for *** than 50 million events of the CDf Run II data have been already processed using this system.

关键词： CDf 数据处理系统质子反质子相互作用

Use of routine HIV testing data for early detection of emerging HIV epidemics in high-risk subpopulations:A concept demonstration study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Infectious Disease Modelling 2018年第1期3卷 373-384页

作者： Houssein H.Ayoub Susanne f.Awad Laith J.Abu-Raddad Department of Mathematics Statisticsand PhysicsQatar UniversityDohaQatar Infectious Disease Epidemiology Group Weill Cornell Medicine-QatarCornell UniversityQatar Foundation-Education CityDohaQatar Department of Healthcare Policy and Research Weill Cornell MedicineCornell UniversityNew YorkUSA College of Health and Life Sciences Hamad Bin Khalifa UniversityDohaQatar

Introduction:HIV epidemics in hard-to-reach high-risk subpopulations are often discovered years after epidemic emergence in settings with poor surveillance *** hypothesis-generation modeling,we aimed to investigate and demonstrate the concept of using routine HIV testing data to identify and characterize hidden epidemics in high-risk *** also compared this approach to surveillance based on AIDS case ***:A deterministic mathematical model was developed to simulate an emerging HIV epidemic in a high-risk subpopulation.A stochastic Monte carlo simulation was implemented on the total population to simulate the sampling process of generating routine HIV testing *** measures were estimated on the simulated epidemic and on the generated testing *** analyses were conducted on the ***:In the simulated epidemic,HIV prevalence saturated at 32%in the high-risk subpopulation and at 0.33%in the total *** epidemic started its emergingepidemic phase 28 years after infection introduction,and saturated 67 years after infection *** the simulated HIV testing sample,a significant time trend in prevalence was identified,and the generated metrics of epidemic emergence and saturation were similar to those of the simulated *** epidemic was identified 4.0(95%CI 3.4e4.6)years after epidemic emergence using routine HIV testing,but 29.7(95%CI 15.8 e52.1)years after emergence using AIDS case *** the sensitivity analyses,none of the sampling biases affected the conclusion of an emerging epidemic,but some affected the estimated epidemic growth ***:Routine HIV testing data provides a tool to identify and characterize hidden and emerging epidemics in high-risk *** approach can be specially useful in resource-limited settings,and can be applied alone,or along with other complementary data,to provide a meaningful characterization of emer

关键词： HIV High-risk subpopulation Surveillance Mathematical modeling Monte carlo simulations Epidemiology Sexually transmitted infection

Silk-ELR co-recombinamer covered stents obtained by electrospinning

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2019年第1期6卷 21-28页

作者： M.Putzu f.Causa Manuel Parente Israel Gonza´lez de Torre J.C.Rodriguez-Cabello P.A.Netti Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale(DICMAPI)University“Federico II”Piazzale Tecchio 8080125 NaplesItaly Interdisciplinary Research Centre on Biomaterials(CRIB) University of Naples Federico IIPiazzale Tecchio 8080125 NapoliItaly Center for Advanced Biomaterials for Health Care@CRIB Istituto Italiano di TecnologiaLargo Barsanti e Matteucci 5380125 NapoliItaly Conic Vascular via Carlo Maderno 236901 LuganoSwitzerland Technical Proteins NanoBioTechnology S.L. Edificio CTTAPaseo de Belen9A47011 ValladolidSpain Networking Research Center on Bioengineering Biomaterials and Nanomedicine(CIBER-BBN)ValladolidSpain Bioforge Lab University of ValladolidEdificio LUCIAPaseo de Belen1947011 ValladolidSpain

In the field of tissue engineering the choice of materials is of great importance given the possibility to use biocompatible polymers produced by means of biotechnology.A large number of synthetic and natural materials have been used to this purpose and processed into scaffolds using Electrospinning *** materials that could be used for the fabrication of scaffold and degradable membranes,natural polymers such as collagen,elastin or fibroin offer the possibility to design structures strictly similar to the extracellular matrix(ECM).Biotechnology and genetic engineering made possible the advent of a new class of biopolymers called protein-based *** example is represented by the silk-elastin-proteins that combine the elasticity and resilience of elastin with the high tensile strength of silk-fibroin and display engineered bioactive *** this work,we use electrospinning technique to produce a fibrous scaffold made of the corecombinamer *** fibres have been characterized from the morphological point of *** and morphology have been explored using Scanning Electron Microscopy.A thorough study regarding the influence of Voltage,flow rate and distance have been carried out to determine the appropriate parameters to obtain the fibrous mats without defects and with a good distribution of *** has also been in vitro *** the first time we use the co-recombinamer Silk-ELR for the fabrication of a 2.5 angioplasty balloon *** structure could be useful as a coated scaffold for the regeneration of intima layer of vessels.

关键词： electrospinning silk elastin-like-recombinamers tissue engineering