检索结果-南通市图书馆

Impact of Friction Stir Welding (FSW) Process Parameters on Thermal Modeling and Heat Generation of Aluminum Alloy Joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 869-883页

作者： Saad B.Aziz Mohammad W.Dewan Daniel J.Huggett Muhammad A.Wahab Ayman M.Okeil T.warren Liao Department of Mechanical and Industrial Engineering Louisiana State University Department of Civil and Environmental Engineering Louisiana State University

Friction stir welding （FSW） is a solid-state joining process, where joint properties largely depend on the amount of heat generation during the welding process. The objective of this paper was to develop a numerical thermomechanical model for FSW of aluminum--copper alloy AA2219 and analyze heat generation during the welding process. The thermomechanical model has been developed utilizing ANSYS APDL. The model was verified by comparing simulated temperature profile of three different weld schedules （i.e., different combinations of weld parameters in real weld situations） from simulation with experimental results. Furthermore, the verified model was used to analyze the effect of different weld parameters on heat generation. Among all the weld parameters, the effect of rotational speed on heat generation is the highest.

关键词： Friction stir welding Frictional dissipation energy Temperature distribution Friction modeling Aluminum alloy

SOX A Comparison With the South African Status Quo

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

Journal of Modern Accounting and Auditing 2012年第3期8卷 357-364页

作者： warren J. Maroun University of the Witwatersrand Johannesburg South Africa

Auditor independence provisions enshrined in the Sarbanes-Oxley Act （SOX） were promulgated in 2002 in response to the Errron-Anderson scandal leading to a diminution of trust in the audit profession. In seeking to regulate auditor independence in the name of investor protection, SOX has been heralded as ＂ground-breaking＂ public interest reform. Ironically, when one considers the substance of these reforms and contrasts them with the situation prevailing in South Africa, a different impression results. Despite the fact that South Africa is classified as a ＂developing＂ nation and one which has only recently transitioned to democracy, many of the auditor independence principles legislated under SOX have been part of generally accepted practice in South Africa since the 1950s. Accordingly, SOX may not be the progressive example of auditor regulation that it is generally perceived to be.

关键词： auditor independence auditing regulations independent regulators Auditing Profession Act (2005),Sarbanes-Oxley Act (2002) South Africa United States of America

A New Approach to Probability Assessment

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 Business Review 2022年第1期21卷 16-18页

作者： warren Richard Hughes University of Waikato HamiltonNew Zealand

Using spreadsheets and ranges for pairwise judgments,candidate probability distributions are generated for the decision-maker to *** replaces event-by-event determination of *** statistics of the distributions are the... 详细信息

关键词： probability assessment pairwise judgments spreadsheet analysis statistical measures

MiR-130a regulates and dendritic spine MeCP2 neurite outgrowth density by targeting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Protein & Cell 2016年第7期7卷 489-500页

作者： Yunjia Zhang Mengmeng Chen Zilong Qiu Keping Hu warren McGee Xiaoping Chen Jianghong Liu Li Zhu Jane Y. Wu State Key Laboratory for Brain & Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China Laboratory of Molecular Basis of Neural Plasticity Institute of Neuroscience Chinese Academy of Sciences Shanghai 200031 China Institute of Medicinal Plant Development (IMPLAD) Chinese Academy of Medical Sciences Beijing 100193 China Department of Neurology Center for Genetic Medicine Lurie Cancer Center Northwestern University Feinberg School of Medicine Chicago IL 60611 USA

MicroRNAs （miRNAs） are critical for both development and function of the central nervous system. Significant evidence suggests that abnormal expression of miRNAs is associated with neurodevelopmental disorders. MeCP2 protein is an epigenetic regulator repressing or activating gene transcription by binding to methylated DNA. Both loss-of-function and gain-of-function muta- tions in the MECP2 gene lead to neurodevelopmental disorders such as Rett syndrome, autism and MECP2 duplication syndrome. In this study, we demonstrate that miR-130a inhibits neurite outgrowth and reduces dendritic spine density as well as dendritic complexity. Bioinformatics analyses, cell cultures and biochemical experiments indicate that miR-130a targets MECP2 and down-regulates MeCP2 protein expression. Further- more, expression of the wild-type MeCP2, but not a loss- of-function mutant, rescues the miR-130a-induced phe- notype. Our study uncovers the MECP2 gene as a pre- vious unknown target for miR-130a, supporting that miR-130a may play a role in neurodevelopment by reg- ulating MeCP2. Together with data from other groups,our work suggests that a feedback regulatory mecha- nism involving both miR-130a and MeCP2 may serve to ensure their appropriate expression and function in neural development.

关键词： miR-130a MECP2 neurite outgrowth,dendritic spines dendrite morphology

Variations in Probability Assessment With Atypical Scenarios

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

Management Studies 2024年第4期12卷 245-247页

作者： warren Richard Hughes University of Waikato HamiltonNew Zealand

Probability assessment in some scenarios may involve unusual aspects such as requiring certain values for some events and extremely high or low probabilities in other cases.

关键词： probability assessment pairwise values spreadsheets

Towards a Technology Agnostic Approach to Developing Mobile Applications and Services

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Software Engineering and Applications 2017年第6期10卷 500-528页

作者： Ian warren Andrew Meads Department of Computer Science University of Auckland Auckland New Zealand

Today’s mobile devices and networks enable the development of novel mobile service applications. Developing such applications raises many challenges including heterogeneity in terms of mobile operating systems and APIs, service availability and scalability, and providing for the diverse communication needs of different applications. In this paper, we present an overview of the Odin middleware platform whose aim is to address these challenges. Odin utilises a surrogate-based architectural model to promote a mobile service’s scalability and availability. The middleware is reconfigurable, allowing mobile applications to adapt to changing operating conditions and minimise resource consumption. It also includes an optimised communication channel that masks the complexity of interacting with mobile services over mobile telecommunications networks. Using Odin’s interfaces and standards compliance, mobile applications and services with consistent communication behaviour can be easily implemented on heterogeneous platforms. Through quantitative evaluation, Odin’s message-based communication primitives have been demonstrated to perform favourably with leading industry push messaging providers.

关键词： Mobile Computing Middleware Mobile Applications Push Notification

Assessing probabilities of unique events： Calibrating qualitative likelihood judgments into a probability distribution

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 Business Review 2010年第9期9卷 54-60页

作者： warren R. Hughes Department of Economics University of Waikato Hamilton 3240 New Zealand

Multifaceted events in an organizational environment usually need to be assigned probabilities as a prerequisite to analytical decision-making. If the decision situation is unique, a lack of relevant historical frequency data may preclude use of traditional probability models such as the normal, binomial etc. In this case, an individual decision maker （DM） or an informed group of persons can input into a procedure as outlined here to determine a probability distribution that leads to the expected values of alternative actions or fair values of securities. The individual or group member must decide qualitatively on the extent to which one event is ＂more likely＂ than another where both events are ranked adjacent （i.e., closest to each other） in terms of likelihood. Even though the individual or group members may lack experience in orthodox probability assessment, these pairwise ＂more likely＂ judgments on the relative likelihood of events are not overly demanding for persons familiar with the possible outcomes in the situation under analysis.

关键词： decision analysis probability assessment Bayesian revision strategic planning

A Fully Coupled Thermomechanical Model of Friction Stir Welding(FSW) and Numerical Studies on Process Parameters of Lightweight Aluminum Alloy Joints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 1-18页

This paper presents a new thermomechanical model of friction stir welding which is capable of simulating the three major steps of friction stir welding （FSW） process, i.e., plunge, dwell, and travel stages. A rate-dependent Johnson- Cook constitutive model is chosen to capture elasto-plastic work deformations during FSW. Two different weld schedules （i.e., plunge rate, rotational speed, and weld speed） are validated by comparing simulated temperature profiles with experimental results. Based on this model, the influences of various welding parameters on temperatures and energy generation during the welding process are investigated. Numerical results show that maximum temperature in FSW process increases with the decrease in plunge rate, and the frictional energy increases almost linearly with respect to time for different rotational speeds. Furthermore, low rotational speeds cause inadequate temperature distribution due to low frictional and plastic dissipation energy which eventually results in weld defects. When both the weld speed and rotational speed are increased, the contribution of plastic dissipation energy increases significantly and improved weld quality can be expected.

关键词： Aluminum alloy Friction stir welding Temperature distribution Plastic energy Frictional energy Rate-dependent model Friction modeling

The Global Stratotype Section and Point （GSSP） for the base of the Katian Stage of the Upper Ordovician Series at Black Knob Ridge, Southeastern Oklahoma, USA

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

Episodes 2007年第4期30卷 258-270页

作者： Daniel Goldman Stephen A. Leslie Jaak Nōlvak Seth Young Stig M. Bergstroem warren D. Huff Department of Geology University of Dayton 300 College Park Dayton Ohio 45469 USA Deparment of Geology and Environmental Science James Madison University MSC 6903 Harrisonburg VA 22807 USA Institute of Geology at Tallinn University of Technology Ehitajate tee 5 19086 Tallinn Estonia School of Earth Sciences Division of Geological Sciences The Ohio State University 155 S. Oval Mall Columbus Ohio 43210 USA Department of Geology University of Cincinnati Cincinnati Ohio 45221 USA.

The Global Boundary Stratotype Section and Point （GSSP） for the Katian Stage of the Upper Ordovician Series is defined as the 4.0 m-level above the base of the Bigfork Chert in the Black Knob Ridge section, southeastern Oklahoma. This point in this section is coincident with the first appearance of the graptolite Diplacanthograptus caudatus, which has proved to be a reliable datum for precise worldwide correlation. The FAD ofD. caudatus occurs very near the first occurrences of the graptolites D. lanceolatus, *** americanus, Orthograptus pageanus, O. quadrimucronatus, Dicranograptus hians, and Neurograptus margaritatus. This rapid succession of fossil species appearance events provides a secure basis for identification of the base of the Katian Stage of the Upper Ordovician Series and for its global chronostratigraphic correlation.

关键词：层形断面奥陶纪俄克拉荷马州美国地质特点