检索结果-南通市图书馆

KINETIC FUNCTIONS IN MAGNETOHYDRODYNAMICS WITH RESISTIVITY AND HALL EFFECT

Acta Mathematica Scientia 2009年第6期29卷 1684-1702页

作者： philippe G. Le Siddhartha Mishra FlochLaboratoire Jacques-Louis Lions Centre National de la Recherche ScientifiqueUniversit Pierre et Marie Curie (Paris 6) 4 Place Jussieu 75258 Paris France Seminar for Applied Mathematics D-Math ETH HG Raemistrasse Zürich-8092 Switzerland

We consider a nonlinear hyperbolic system of two conservation laws which arises in ideal magnetohydrodynamics and includes second-order terms accounting for magnetic resistivity and Hall effect. We show that the initial value problem for this model may lead to solutions exhibiting complex wave structures, including undercompressive nonclassical shock waves. We investigate numerically the subtle competition that takes place between the hyperbolic, diffusive, and dispersive parts of the system. Following Abeyratne, Knowles, LeFloch, and Truskinovsky, who studied similar questions arising in fluid and solid flows, we determine the associated kinetic function which characterizes the dynamics of undereompressive shocks driven by resistivity and Hall effect. To this end, we design a new class of ＂schemes with eontroled dissipation＂, following recent work by LeFloch and Mohammadian. It is now recognized that the equivalent equation associated with a scheme provides a guideline to design schemes that capture physically relevant, nonclassical shocks. We propose a new class of schemes based on high-order entropy conservative, finite differences for the hyperbolic flux, and high-order central differences for the resistivity and Hall terms. These schemes are tested for several regimes of （co-planar or not） initial data and parameter values, and allow us to analyze the properties of nonclassical shocks and establish the existence of monotone kinetic functions in magnetohydrodynamics.

关键词： hyperbolic conservation law magnetohydrodynamics magnetic resistivity Hall effect undercompressive shock kinetic function

来源：

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

Machine learning applied to road safety modeling:A systematic literature review

引用

Journal of Traffic and Transportation Engineering(English Edition) 2020年第6期7卷 775-790页

作者： philippe Barbosa Silva Michelle Andrade Sara Ferreira Department of Civil Engineering Goiano Federal Institute-Rio Verde CampusRio Verde 75901-970Brazil Department of Civil and Environmental Engineering University of BrasiliaBrasilia 70910-900Brazil Research Centre for Territory Transports and EnvironmentUniversity of PortoPorto 4200-465Portugal

Road safety modeling is a valuable strategy for promoting safe mobility,enabling the development of crash prediction models(CPM)and the investigation of factors contributing to crash *** modeling has traditionally used statistical techniques despite acknowledging the limitations of this kind of approach(specific assumptions and prior definition of the link functions),which provides an opportunity to explore alternatives such as the use of machine learning(ML)*** study reviews papers that used ML techniques for the development of CPM.A systematic literature review protocol was conducted,that resulted in the analysis of papers and their *** types of models were identified:crash frequency,crash classification by severity,and crash frequency and *** first is a regression problem,the second,a classificatory one and the third can be approached either as a combination of the preceding two or as a regression model for the expected number of crashes by severity *** main groups of techniques used for these purposes are nearest neighbor classification,decision trees,evolutionary algorithms,support-vector machine,and artificial neural *** last one is used in many kinds of approaches given the ability to deal with both regression and classification problems,and also multivariate response *** paper also presents the main performance metrics used to evaluate the models and compares the results,showing the clear superiority of the ML-based models over the statistical *** addition,it identifies the main explanatory variables used in the models,which shows the predominance of road-environmental aspects as the most important factors contributing to crash *** review fulfilled its objective,identifying the various approaches and the main research characteristics,limitations,and opportunities,and also highlighting the potential of the usage of ML in crash analyses.

关键词： Transportation engineering Road safety modeling Crash prediction Crash injury severity Machine learning Systematic literature review

来源：

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

Genetic Enhancement of Indigenous Cowpea with Gamma-Ray Induced Trait Variation

引用

American Journal of Plant Sciences 2024年第8期15卷 651-676页

作者： Mathurin Tiergnin Dabiré Minimassom philippe Nikiéma Djibril Yonli Safiatou Sanna Wossoguim Josué Gouba Siébou Palé Hamidou Traoré Joseph T. B. Batieno Varra Prasad Zacharia Stewart Jan B. Middendorf Abhishek Rathore Anupama J. Hingane Unit de Formation et de Recherches en Sciences et Technologies Dpartement des Sciences de la Vie et de la Terre Universit Norbert ZONGO Koudougou Burkina Faso Institut de lEnvironnement et de Recherches Agricoles (INERA) Ouagadougou Burkina Faso Department of Agronomy Kansas State University Manhattan USA Center for Agriculture-Led Growth Bureau for Resilience and Food Security United States Agency for International Development United States Agency for International Development Washington DC USA International Maize and Wheat Improvement Center (CIMMYT) ICRISAT Campus Patancheru India Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture Department of Nuclear Sciences and Applications Plant Breeding and Genetics Laboratory International Atomic Energy Agency (IAEA) Seibersdorf Vienna Austria

Production of cowpea (Vigna unguiculata (L.) Walp.), a staple legume crop in Sub-Saharan Africa, faces challenges due to biotic and abiotic constraints. Induced mutagenesis was deployed to create genetic variation in two cowpea varieties (KVX396-4-5-2D and Moussa local). The radio-sensitivity tests led to determe the lethal dose 50 (LD50) corresponding to 230 Gy and 220 Gy for KVX396-4-5-2D and Moussa local varieties, respectively. Dried seeds (M0) of each variety were gamma-ray irradiated with LD50 − 50, LD50 and LD50 + 50. M1 seeds were advanced to generate M2, M3 and M4 mutants using the single-seed-descent method. M4 mutant lines were evaluated in rain-fed conditions using a randomized complete block design to assess phenotypic differences. Data on seven qualitative and eleven quantitative traits were collected. The results indicated that the mutation induced variability in three qualitative traits: in KVX 396-4-5-2D mutant lines, with flower and seed color frequencies at 2.61% and 0.56% respectively, and pod dehiscence at a frequency of 0.24%. While in Moussa local mutants, a pod color changed at a frequency of 17%. ANOVA results revealed significant differences between mutants of both varieties for all quantitative traits, including photosynthetic parameters. Positive correlations were observed between leaf diameter and 100-seed weight, and between branch number and 100-seed weight. Hierarchical clustering revealed three clusters among KVX 396-4-5-2D mutants and six clusters among Moussa local mutants. Early maturity and high foliage were induced traits in Cluster 3 of KVX 396-4-5-2D mutants while high hundred-seed weight was induced in Cluster 6 of Moussa local mutants.

关键词： Cowpea Mutagenesis Gamma Rays Radio-Sensitivity Phenotyping

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Radical-mediated hydroalkylation of 2-vinylpyrrolidine derivatives: a versatile entry into indolizidine alkaloids

引用

Science China Chemistry 2019年第11期62卷 1504-1506页

作者： Sankar Rao Suravarapu Bettina Peter philippe Renaud Department of Chemistry and Biochemistry University of Bern

A concise route for the preparation of two simple optically pure indolizidin-5-ones has been *** key chain elongation process was achieved using a triethylborane/catechol mediated hydroalkylation of Boc-protected *** using complementary strategies,these two bicyclic lactams can be alkylated with complete control of the stereochemistry at C(5)and their conversion to a variety of indolizidine alkaloids such as coniceine,indolizidine 209D and 167B,5-epi-indolizidine 249A and monomorine has been reported in the literature.

关键词： alkenes carbohydrogenation radical reaction catechol triethylborane α-iodoesters allylamine

来源：

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

SECOND-ORDER CONVERGENCE PROPERTIES OF TRUST-REGION METHODS USING INCOMPLETE CURVATURE INFORMATION, WITH AN APPLICATION TO MULTIGRID OPTIMIZATION

引用

Journal of Computational Mathematics 2006年第6期24卷 676-692页

作者： Serge Gratton Annick Sartenaer philippe L. Toint CERFACS av. G. Coriolis Toulouse France Department of Mathematics University of Namur 61 rue de Bruxelles B-5000 Namur Belgium

Convergence properties of trust-region methods for unconstrained nonconvex optimization is considered in the case where information on the objective function＇s local curvature is incomplete, in the sense that it may be restricted to a fixed set of ＂test directions＂ and may not be available at every iteration. It is shown that convergence to local ＂weak＂ minimizers can still be obtained under some additional but algorithmically realistic conditions. These theoretical results are then applied to recursive multigrid trust-region methods, which suggests a new class of algorithms with guaranteed second-order convergence properties.

关键词： Nonlinear optimization Convergence to local minimizers Multilevel problems.

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Using experimental data to reduce the single-building sigma of fragility curves:case study of the BRD tower in Bucharest,Romania

引用

Earthquake Engineering and Engineering Vibration 2013年第4期12卷 643-658页

作者： Matthieu Perrault philippe Gueguen Alexandru Aldea Sorin Demetriu Institut des Sciences de la Terre Université Joseph Fourier Grenoble ICNRS/IFSTTAR Technical University of Civil Engineering

The lack of knowledge concerning modelling existing buildings leads to significant variability in fragility curves for single or grouped existing buildings. This study aims to investigate the uncertainties of fragility curves, with special consideration of the single-building sigma. Experimental data and simplified models are applied to the BRD tower in Bucharest, Romania, a RC building with permanent instrumentation. A three-step methodology is applied：（1） adjustment of a linear MDOF model for experimental modal analysis using a Timoshenko beam model and based on Anderson＇s criteria, （2） computation of the structure＇s response to a large set of accelerograms simulated by SIMQKE software, considering twelve ground motion parameters as intensity measurements （IM）, and （3） construction of the fragility curves by comparing numerical interstory drift with the threshold criteria provided by the Hazus methodology for the slight damage state. By introducing experimental data into the model, uncertainty is reduced to 0.02 considering Sd ） as seismic intensity IM and uncertainty related to the model is assessed at 0.03. These values must be compared with the total uncertainty value of around 0.7 provided by the Hazus methodology.

关键词： vulnerability fragility curves uncertainty slight damage Timoshenko model Bucharest

来源：

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

Epidemiology and risk factors for mortality in critically ill patients with pancreatic infection

引用

Journal of Intensive Medicine 2024年第1期4卷 81-93页

作者： Marie Dejonckheere Massimo Antonelli Kostoula Arvaniti Koen Blot Ben CreaghBrown Dylan Wde Lange Jan De Waele Mieke Deschepper Yalim Dikmen George Dimopoulos Christian Eckmann Guy Francois Massimo Girardis Despoina Koulenti Sonia Labeau Jeffrey Lipman Fernando Lipovestky Emilio Maseda philippe Montravers Adam Mikstacki JoseArtur Paiva Cecilia Pereyra Jordi Rello JeanFrancois Timsit Dirk Vogelaers Stijn Blot the Abdominal Sepsis Study(AbSeS)group on behalf of the Trials Group of the European Society of Intensive Care Medicine Department of Internal Medicine and Pediatrics Faculty of Medicine and Health SciencesGhent UniversityGhentBelgium Department of Anesthesiology Intensive Care and Emergency MedicineFondazione Policlinico Universitario A.Gemelli IRCCSRomeItaly UniversitàCattolica del Sacro Cuore RomeItaly Intensive Care Unit Papageorgiou University Affiliated HospitalThessaloníkiGreece Department of Epidemiology and Public Health SciensanoIxellesBelgium Surrey Perioperative Anaesthetic Critical Care Collaborative Research Group(SPACeR) Royal Surrey County HospitalGuildfordUK Department of Clinical and Experimental Medicine University of SurreyGuildfordUK Department of Intensive Care Medicine University Medical Center UtrechtUniversity UtrechtUtrechtthe Netherlands Department of Intensive Care Medicine Ghent University HospitalGhentBelgium Data Science Institute Ghent University HospitalGhentBelgium Department of Anesthesiology and Reanimation Cerrahpasa School of MedicineIstanbul University-CerrahpasaIstanbulTurkey rd Department of Critical Care “EVGENIDIO”HospitalNational and Kapodistrian University of AthensAthensGreece Department of General Visceral and Thoracic SurgeryKlinikum Hannoversch-MuendenGoettingen UniversityGöttingenGermany Division of Scientific Affairs-Research European Society of Intensive Care MedicineBrusselsBelgium Anesthesia and Intensive Care Department University Hospital of ModenaModenaItaly UQ Centre for Clinical Research Faculty of MedicineThe University of QueenslandBrisbaneQLDAustralia nd Critical Care Department Attikon University HospitalAthensGreece Department of Nursing Faculty of EducationHealth and Social WorkUniversity College GhentGhentBelgium Jamieson Trauma Institute The University of QueenslandBrisbaneQLDAustralia Nimes University Hospital University of MontpellierNimesFrance Critical Care Department Hospital of the Interamerican Open University(UAI)Buenos AiresArgentina Surgical Critical Care Department of AnesthesiaHospital Universitario

Background:The AbSeS-classification defines specific phenotypes of patients with intra-abdominal infection based on the(1)setting of infection onset(community-acquired,early onset,or late-onset hospital-acquired),(2)presence or absence of either localized or diffuse peritonitis,and(3)severity of disease expression(infection,sepsis,or septic shock).This classification system demonstrated reliable risk stratification in intensive care unit(ICU)patients with intra-abdominal *** study aimed to describe the epidemiology of ICU patients with pancreatic infection and assess the relationship between the components of the AbSeS-classification and ***:This was a secondary analysis of an international observational study(“AbSeS”)investigating ICU patients with intra-abdominal *** patients with pancreatic infection were included in this analysis(n=165).Mortality was defined as ICU mortality within 28 days of observation for patients discharged earlier from the *** with mortality were assessed using logistic regression analysis and reported as odds ratio(OR)and 95%confidence interval(CI).Results:The overall mortality was 35.2%(n=58).The independent risk factors for mortality included older age(OR=1.03,95%CI:1.0 to 1.1 P=0.023),localized peritonitis(OR=4.4,95%CI:1.4 to 13.9 P=0.011),and persistent signs of inflammation at day 7(OR=9.5,95%CI:3.8 to 23.9,P<0.001)or after the implementation of additional source control interventions within the first week(OR=4.0,95%CI:1.3 to 12.2,P=0.013).Gramnegative bacteria were most frequently isolated(n=58,49.2%)without clinically relevant differences in microbial etiology between survivors and ***:In pancreatic infection,a challenging source/damage control and ongoing pancreatic inflammation appear to be the strongest contributors to an unfavorable short-term *** this limited series,essentials of the AbSeS-classification,such as the setting of infection onset,diffuse

关键词： Pancreatic infection Intensive care unit Mortality Intra-abdominal infection Sepsis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Identification of biomarkers of human pancreatic adenocarcinomas by expression profiling and validation with gene expression analysis in endoscopic ultrasound-guided fine needle aspiration samples

引用

World Journal of Gastroenterology 2006年第21期12卷 3344-3351页

作者： Henrik Laurell Michèle Bouisson philippe Berthelémy philippe Rochaix Sébastien Déjean philippe Besse Christiana Susini Lucien Pradayrol Nicole Vaysse Louis Buscail INSERM U531 IFR31 Institut Louis BugnardBP 8422531432 Toulouse Cedex 4France Service de Gastroentérologie Centre Hospitaller de Pau PauFrance Laboratoire d'Anatomo-Pathologie Institut Claudius Regaud ToulouseFrance Laboratoire de Statistique et Probabilités Université Paul Sabatier ToulouseFrance INSERM U531 IFR31 Institut Louis BugnardBP 8422531432 Toulouse Cedex 4France Service de Gastroenterologie et de la NutritionCHU RangueilToulouseFrance

AIM： To compare gene expression profiles of pancreatic adenocarcinoma tissue specimens, human pancreatic and colon adenocarcinoma and leukemia cell lines and normal pancreas samples in order to distinguish differentially expressed genes and to validate the differential expression of a subset of genes by quantitative real-time RT-PCR （RT-QPCR） in endoscopic ultrasound-guided fine needle aspiration （EUS-guided FNA） ***： Commercially dedicated cancer cDNA macroarrays （Atlas Human Cancer 1.2） containing 1176 genes were used. Different statistical approaches （hierarchical clustering, principal component analysis （PCA） and SAM） were used to analyze the expression data. RT-QPCR and immunohistochemical studies were used for validation of ***： RT-QPCR validated the increased expression of LCN2 （lipocalin 2） and for the first time PLAT （tissue-type plasminogen activator or tPA） in malignant pancreas as compared with normal pancreas. Immunohistochemical analysis confirmed the increased expression of LCN2 protein localized in epithelial cells of ducts invaded by carcinoma. The analysis of PLAT and LCN2 transcripts in 12 samples obtained through EUS-guided FNA from patients with pancreatic adenocarcinoma showed significantly increased expression levels in comparison with those found in normal tissues, indicating that a sufficient amount of high quality RNA can be obtained with this ***： Expression profiling is a useful method to identify biomarkers and potential target genes. Molecular analysis of EUS-guided FNA samples in pancreatic cancer appears as a valuable strategy for the diagnosis of pancreatic adenocarcinomas.

关键词： Pancreas Colon Adenocarcinoma Gene expression profiling Endoscopic ultrasonography Ultrasound Fine needle aspiration

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Redox and acetylation coordinate ABA-independent osmotic stress response

引用

Molecular Plant 2022年第4期15卷 583-585页

作者： Christophe Belin Jean-philippe Reichheld Laboratoire Génome et Développement des Plantes UniversitéPerpignan Via Domitia66860 PerpignanFrance Laboratoire Génome et Développement des Plantes CNRS66860 PerpignanFrance

Osmotic stress caused by drought or high salt concentrations is a major threat that limits plant development and affect crop *** the context of climate change,understanding the mechanisms by which plants perceive their environment to adapt to their development is a major question.A common feature of plants being exposed to osmotic stress is the accumulation of excessive reactive oxygen species(ROS)(Martinière et al.,2019).ROS can oxidatively damage biological molecules,such as nucleic acids,proteins,and lipids,but also play important signaling *** protect from ROS-induced oxidation,living organisms have developed a large panel of enzymatic and non-enzymatic systems to remove ROS and oxidized molecules.

关键词： functions. enzymatic coordinate

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Economic and Human Loss Empirical Models for Earthquakes in the Mediterranean Region, with Particular Focus on Algeria

引用

International Journal of Disaster Risk Science 2017年第4期8卷 415-434页

作者： Abdelheq Guettiche philippe Guguen Mostefa Mimoune Centre Universitaire Abdelhafid Boussouf Civil Engineering Department Universitdes Frères Mentouri Institut des Sciences de la Terre (ISTerre) Universitde Grenoble Alpes/CNRSIFSTTAR

In this study, loss estimation models were developed for reasonably accurate assessment of economic and human losses from seismic events in the Mediterranean region, based on damage assessment at an urban *** were compiled from existing worldwide databases,and completed with earthquake information from regional studies. Economic data were converted to a single common currency unit(2015 USD value) and the wealth of the areas affected by 65 earthquakes of the region from 1900 to 2015 was assessed. Reduced-form models were used to determine economic and human losses, with earthquake magnitude and intensity as hazard-related variables, and gross domestic product of the affected area and the affected population as exposure-related variables. Damage to buildings was also used as a hazard-related variable to predict economic and human losses. Finally, site-specific regression models were proposed for economic and human losses due to earthquakes in the Mediterranean region, and more specifically, in Algeria. We show that by introducing the damage variable into the models, prediction error can be reduced, and that accuracy of loss model estimation is site dependent and requires regional data on earthquake losses to improve. A case study for Constantine, Algeria shows the improvements needed for increased accuracy.

关键词： Algeria Earthquake loss estimation Mediterranean region Reduced-form models Seismic intensity Seismic magnitude

来源：

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

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：