检索结果-南通市图书馆

On the experimental characterization of the fluid volume influence on the friction between rough surfaces

在线全文

学校读者我要写书评

暂无评论

Friction 2023年第7期11卷 1334-1348页

作者： Lukas STAHL michael mÜLLER Georg-peter OSTERmEYER Institute of Dynamics and Vibrations Technische Universität BraunschweigBraunschweig 37106Germany

The load-bearing behaviour of lubricated contacts depends primarily on the normal force,the relative velocity,and the ***,with the aid of the Stribeck curve,it is usually well possible to characterize whether hydrodynamics,mixed friction,or boundary friction is more likely to be *** fact that the load regime can also depend on the fluid quantity is obvious,but has hardly been systematically investigated so *** for contacts with microscopic roughness,the defined application of a very small amount of fluid is a very challenging *** this paper,a very fundamental study shows how a pin-on-disc tribometer can be used to achieve the transition from dry friction via mixed friction to predominant hydrodynamics by the amount of supplied *** experiments are carried out on samples filed with different *** addition,the simultaneous influence of partial filling and normal force as well as relative velocity is also *** good reproducibility has been practically reached over the entire range of the *** the quantities for the coefficient of friction(COF),it was concluded that close to full filling,a reduction of the fluid quantity has a similar effect on the COF as the reduction of the *** property goes along with the common theory of starved lubricated *** behaviour was not observed to the same extent for the normal *** the vicinity of smaller fluid quantities,the COF increases very rapidly with further reduction in fluid quantity,far more disproportionately than that with reduction in *** a deeper understanding of this problem,various practical issues such as idling or the run-up process in bearings can also be studied in a more focused manner.

关键词： starved lubrication Stribeck curve pin-on-disc tribometer fluid supply experimental studies

Gamma-ray bursts and their links with supernovae and cosmology

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2012年第8期12卷 1139-1161页

作者： peter mszros Neil Gehrels Center for Particle and Gravitational Astrophysics Dept.of Astronomy&Astrophysics and Dept.of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA Astrophysics Science Division NASA Goddard Space Flight CenterGreenbeltMD 20771USA

Gamma-ray bursts are the most luminous explosions in the Universe, whose origin and mechanism are the focus of intense interest. They appear connected to su- pernova remnants from massive stars or the merger of their remnants, and their bright- ness makes them temporarily detectable out to the largest distances yet explored in the universe. After pioneering breakthroughs from space and ground experiments, their study is entering a new phase with observations from the recently launched Fermi satellite, as well as the prospect of detections or limits from large neutrino and gravitational wave detectors. The interplay between such observations and theoretical models of gamma-ray bursts is reviewed, and cosmology. as well as their connections to supernovae

关键词： gamma-ray sources -- gamma-ray bursts -- cosmic rays -- neutrinos-- supernovae -- cosmology -- intergalactic medium

Drug treatment of functional dyspepsia

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2006年第17期12卷 2694-2700页

作者： Klaus mnkemüller peter malfertheiner Division of Gastroenterology Hepatology and Infectious Diseases Otto-von-Guericke Medical SchoolUniversity of MagdeburgMagdeburgGermany

Symptomatic improvement of patients with functional dyspepsia after drug therapy is often incomplete and obtained in not more than 60% of patients. This is likely because functional dyspepsia is a heterogeneous disease. Although great advance has been achieved with the consensus definitions of the Rome I and II criteria, there are still some aspects about the definition of functional dyspepsia that require clarification. The Rome criteria explicitly recognise that epigastric pain or discomfort must be the predominant complaint in patients labelled as suffering from functional dyspepsia. However, this strict definition can create problems in the daily primary care clinical practice, where the patient with functional dyspepsia presents with multiple symptoms. Before starting drug therapy it is recommended to provide the patient with an explanation of the disease process and reassurance. A thorough physical examination and judicious use of laboratory data and endoscopy are also indicated. In general, the approach to treat patients with functional dyspepsia based on their main symptom is practical and effective. Generally, patients should be treated with acid suppressive therapy using proton-pump inhibitors if the predominant symptoms are epigastric pain or gastroesophageal reflux symptoms. Although the role of Helicobacter pylori （H pylon） in functional dyspepsia continues to be a matter of debate, recent data indicate that there is modest but clear benefit of eradication of H pylori in patients with functional dyspepsia. In addition, H pylori is a gastric carcinogen and if found it should be eliminated. Although there are no specific diets for patients with FD, it may be helpful to guide the patients on healthy exercise and eating habits.

关键词： Functional dyspepsia Drug treatment Helicobacterpylori Predominant symptoms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

嘌呤信号:中医药研究新靶点

成都中医药大学学报 2024年第3期47卷 1-7页

作者：尹海燕 Patrizia Rubini peter Illes 唐勇成都中医药大学针灸推拿学院四川成都611137 嘌呤信号国际联合研究中心四川成都611137 莱比锡大学医学院德国莱比锡04107 成都中医药大学养生康复学院四川成都611137

嘌呤信号主要包括三磷酸腺苷(Adenosine Triphosphate,ATP)、二磷酸腺苷(Adenosine Diphosphate,ADP)、一磷酸腺苷(Adenosine monophosphate,AmP)和腺苷(Adenosine,ADO)4类物质、CD39和CD73两种酶以及19种嘌呤受体(P1、P2X、P2Y),与机... 详细信息

关键词：嘌呤信号中医药靶点

Projection on Segre varieties and determination of holomorphic mappings between real submanifolds Dedicated to Professor Sheng GONG on the occasion of his 75th birthday

在线全文

学校读者我要写书评

暂无评论

Science China mathematics 2006年第11期49卷 1611-1624页

作者： BAOUENDI m S EBENFELT peter ROTHSCHILD Linda P Department of mathematics University of California at San Diego La JollaCA 92093-0112USA

It is shown that a germ of a holomorphic mapping sending a real-analytic generic submanifold of finite type into another is determined by its projection on the Segre variety of the target manifold. A necessary and sufficient condition is given for a germ of a mapping into the Segre variety of the target manifold to be the projection of a holomorphic mapping sending the source manifold into the target. An application to the biholomorphic equivalence problem is also given.

关键词： Segre variety, generic submanifold, Segre mappings, finite type, biholomorphic equivalence.

Semantic linking of complex properties,monitoring processes and facilities in web-based representations of the environment

在线全文

学校读者我要写书评

暂无评论

International Journal of Digital Earth 2016年第3期9卷 300-324页

作者： Adam m.Leadbetter peter N.Vodden marine Institute Co.GalwayIreland Centre for Ecology and Hydrology Lancaster Environment CentreLancasterUK

Where a virtual representation of the Earth must contain data values observed within the physical Earth system,data models are required that allow the integration of data across the silos of various Earth and environmental sciences *** a mapping between the well-defined terminologies of these silos is a stubborn *** paper presents a generalised ontology for use within Web 3.0 services,which builds on European Commission spatial data infrastructure *** presented ontology acknowledges that there are many complexities to the description of environmental properties which can be observed within the physical Earth *** ontology is shown to be flexible and robust enough to describe concepts drawn from a range of Earth science disciplines,including ecology,geochemistry,hydrology and *** paper also demonstrates the alignment and compatibility of the ontology with existing systems and shows applications in which the ontology may be deployed.

关键词： observable properties monitoring properties environmental monitoring facilities semantic web geospatial data integration

The genetics and biology of KRAS in lung cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Cancer 2013年第2期32卷 63-70页

作者： peter m.K.Westcott minh D.To Pharmaceutical Sciences and Pharmacogenomics Program University of California SanFrancisco Helen Diller Comprehensive Cancer Center University of California SanFrancisco Thoracic Oncology Program Department of SurgeryUniversity of California SanFrancisco

mutational activation of KRAS is a common oncogenic event in lung cancer and other epithelial cancer *** to develop therapies that counteract the oncogenic effects of mutant KRAS have been largely unsuccessful,and cancers driven by mutant KRAS remain among the most refractory to available *** undertaken over the past decades have produced a wealth of information regarding the clinical relevance of KRAS mutations in lung *** Kras-driven mouse models of cancer,together with cellular and molecular studies,have provided a deeper appreciation for the complex functions of KRAS in ***,a much more thorough understanding of these complexities is needed before clinically effective therapies targeting mutant KRAS-driven cancers can be achieved.

关键词： RAS基因肺癌生物学遗传学基因突变致癌作用临床意义小鼠模型

A Novel ABA Insensitive mutant of Lotus japonicus with a Wilty Phenotype Displays Unaltered Nodulation Regulation

在线全文

学校读者我要写书评

暂无评论

molecular Plant 2009年第3期2卷 487-499页

作者： Bandana Biswas Pick Kuen Chan peter m Gresshoff ARC Centre of Excellence for Integrative Legume Research The University of Queensland St Lucia Brisbane QId 4072 Australia

An ABA insensitive mutant, Beyma, was isolated in Lotus japonicus mG-20 from an EmS mutagenesis population using root growth inhibition to applied ABA as the screening criterion. （The name ＂Beyma＂ was taken from the Australian Aboriginal language, Wagiman, beyma, meaning ‘drying up＇.） The stable mutant that segregates as a dominant mendelian mutation is insensitive to ABA induced inhibition of germination, vegetative growth, stomatal opening, as well as nodulation. Tissue ABA levels were normal, suggesting a sensitivity rather than biosynthesis mutation. It is slow-growing （50-70% of wild-type mG-20） and has a near-constitutive wilty phenotype associated with its inability to regulate stomatal opening. Whilst showing a wide range of ABA insensitive phenotypes, Beyma did not show alteration of nodule number control, as, in the absence of added ABA, the number and patterning （but not size） of nodules formed in the mutant were similar to that of mG-20. Split root experiments on mG-20 showed that application of ABA on one side of the root inhibited nodulation locally but not systemically. We propose that ABA is not involved directly in systemic autoregulation of nodulation （AON）.

关键词： hormone biology water relations genetics development symbiosis legume.

On some aspects of minimum redundancy maximum relevance feature selection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2020年第1期63卷 89-103页

作者： peter BUGATA peter DROTAR Intelligent Information Systems Lab Technical University of Kosice

The feature selection is an important challenge in many areas of machine learning because it plays a crucial role in the interpretations of machine-driven decisions. There are various approaches to the feature selection problem and methods based on the information theory comprise an important ***, the minimum redundancy maximum relevance(m RmR) feature selection is undoubtedly the most popular one with widespread application. In this paper, we prove in contrast to an existing finding that the m RmR is not equivalent to max-Dependency criterion for first-order incremental feature selection. We present another form of equivalence leading to a generalization of m RmR feature selection. Additionally,we compare several feature selection methods based on m RmR, max-Dependency, and feature ranking,employing different measures of dependency. The results on high-dimensional real-world datasets show that the distance correlation is the suitable measure for dependency-based feature selection methods. The results also indicate that the max-Dependency incremental algorithm combined with distance correlation appears to be a promising feature selection approach.

关键词： big data information theory feature selection dimensionality reduction minimum redundancy maximum relevance m RmR