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Evolution of heat transport pathways in the Indonesian Archipelago during last deglaciation

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Chinese Science Bulletin 2002年第22期47卷 1912-1917页

作者： f.Guichard f.Bassinot l.labeyrie China University of Geosciences (Beijing) Beijing China laboratoire des Sciences du Climat et de l’Environnement Domaine du CNRS Gif-sur-Yvette France

The Indonesian Archipelago provides important heat transport pathways of the Western Pacific Warm Pool between the northern Indian Ocean and western equatorial Pacific Ocean, that exert important impacts on global climate change. This study investigated AMS 14C, δ18O, planktonic foraminifer assemblages and sedimentation rates in three piston cores collected in the Indonesian Archipelago. The results indicate that changes in the Indonesian Archipelago heat transport pathways were phase characteristic and in steps during the last deglaciation. In the deglaciation Termination IA, at about 12.5 kaBP, sea level rose rapidly in a short time period, and Makassar and lombok straits widened suddenly for warm and fresh water from the Pacific to pour into the Java Sea and eastern Indian Ocean. During the Termination IB, about 9.5 kaBP, sea level rose rapidly again, and the South China Sea (SCS) started to connect with the Java Sea. With monsoon actions, a large amount of fresh water from the SCS shelf area flew

关键词： Indonesian Archipelago last deglaciation heat transport pathways β18O planktonic foraminifer assemblages.

Model reference adaptive impedance control for physical human-robot interaction

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Control Theory and Technology 2016年第1期14卷 68-82页

作者： Bakur AlQAUDI Hamidreza MODARES Isura RANATUNGA Shaikh M. TOUSIf frank l. lewis Dan O. POPA The University of Texas at Arlington Research Institute (UTARI) Fort Worth TX 76118 U.S.A. Department of Electrical Engineering College of Engineering The University of Texas at Arlington Arlington TX 76019 U.S.A. Electronics and Instrumentation Engineering Technology Department Yanbu Industrial College P.O. Box 30436 41912 Yanbu al-Sinaiyah K.S.A. State Key laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang Liaoning 110819 China

This paper presents a novel enhanced human-robot interaction system based on model reference adaptive control. The presented method delivers guaranteed stability and task performance and has two control loops. A robot-specific inner loop, which is a neuroadaptive controller, learns the robot dynamics online and makes the robot respond like a prescribed impedance model. This loop uses no task information, including no prescribed trajectory. A task-specific outer loop takes into account the human operator dynamics and adapts the prescribed robot impedance model so that the combined human-robot system has desirable characteristics for task performance. This design is based on model reference adaptive control, but of a nonstandard form. The net result is a controller with both adaptive impedance characteristics and assistive inputs that augment the human operator to provide improved task performance of the human-robot team. Simulations verify the performance of the proposed controller in a repetitive point-to-point motion task. Actual experimental implementations on a PR2 robot further corroborate the effectiveness of the approach.

关键词： Human-robot interaction model reference adaptive control model reference neuroadaptive impedance control

Spalling characteristics of high-temperature treated granitic rock at different strain rates

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1280-1288页

作者： l.f.fan Q.H.Yang X.l.Du The Key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spalling characteristics of rock are important for stability analysis in rock *** paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different *** dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain *** results show that the spalling strength of granite decreases with increasing ***,the spalling strength of granite with a higher strain rate is larger than that with a lower strain *** proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate.

关键词： Dynamic spalling characteristics High temperature Strain rate Dynamic loading Granite

IUGS Commission on Geoscience Edoucation, Training and Technology Transfer （COGE） http ：//***/IUGSeducation/***

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Episodes 2006年第4期29卷 310-311页

作者： Gary lewis Wesley Hill The Geological Society of America 3300 Penrose Place Boulder Colorado 80301 USA 303-357-1043 The Geological Society of America 3300 Penrose Place Boulder Colorado 80301 USA

In previous years, IUGS conducted a programme in the area of Geoscience Education and Training. The programme was organised under the status of a Working Group or a Commission. The IUGS level of activities in past years in Geoscience Education （COGEOED） was generally low and so the IUGS Executive Committee considered this body dormant. The IUGS Strategic Planning Committee recommended in its report that, ＇Technology-transfer and geological education focusing on developing countries should continue to be key-activities of the IUGS＇.

关键词：地质科学地质工作地质科学教育行业交流

Galerkin-laguerre Spectral Solution of Self-Similar Boundary layer Problems

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Communications in Computational Physics 2012年第10期12卷 1329-1358页

作者： f.Auteri l.Quartapelle Politecnico di Milano Dipartimento di Ingegneria AerospazialeVia La Masa 3420156MilanoItaly

In this work the laguerre basis for the biharmonic equation introduced by Jie Shen is employed in the spectral solution of self-similar problems of the boundary layer *** original Petrov-Galerkin formulation of the falkner-Skan equation is presented which is based on a judiciously chosen special basis function to capture the asymptotic behaviour of the unknown.A spectral method of remarkable simplicity is obtained for computing falkner-Skan-Cooke boundary layer *** accuracy and efficiency of the laguerre spectral approximation is illustrated by determining the linear stability of nonseparated and separated flows according to the Orr-Sommerfeld *** pentadiagonal matrices representing the derivative operators are explicitly provided in an Appendix to aid an immediate implementation of the spectral solution algorithms.

关键词： laguerre polynomials semi-infinite interval boundary layer theory falkner-Skan equation Cooke equation Orr-Sommerfeld equation linear stability of parallel flows

Spectral Matrix Conditioning in Cylindrical and Spherical Elliptic Equations

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Numerical Mathematics(Theory,Methods and Applications) 2011年第2期4卷 113-141页

作者： f.Auteri l.Quartapelle Politecnico di Milano Dipartimento di Ingegneria AerospazialeVia La Masa 3420156 MilanoItaly

In the spectral solution of 3-D Poisson equations in cylindrical and spherical coordinates including the axis or the center,it is convenient to employ radial basis functions that depend on the fourier wavenumber or on the latitudinal *** idea has been adopted by Matsushima and Marcus and by Verkley for planar problems and pursued by the present authors for spherical *** the Dirichlet boundary value problem in both geometries,original bases have been introduced built upon Jacobi polynomials which lead to a purely diagonal representation of the radial second-order differential operator of all spectral *** note details the origin of such a diagonalization which extends to cylindrical and spherical regions the properties of the legendre basis introduced by Jie Shen for Cartesian *** form expressions are derived for the diagonal elements of the stiffness matrices as well as for the elements of the tridiagonal mass matrices occurring in evolutionary ***,the bound on the condition number of the spectral matrices associated with the Helmholtz equation are determined,proving in a rigorous way one of the main advantages of the proposed radial bases.

关键词： Poisson equation cylindrical and spherical coordinates fourier expansion spherical harmonics Jacobi polynomials spectral methods condition number

Reliability of quasi integrable and non-resonant Hamiltonian systems under fractional Gaussian noise excitation

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Acta Mechanica Sinica 2020年第4期36卷 902-909页

作者： Q.f.lu W.Q.Zhu M.l.Deng Department of Mechanics State-Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China

The reliability of quasi integrable and non-resonant Hamiltonian system under fractional Gaussian noise(fGn)excitation is *** rather flat fGn power spectral density(PSD)in most part of frequency band,the fGn is innovatively regarded as a wide-band ***,the stochastic averaging method for quasi integrable Hamiltonian systems under wide-band noise excitation is applied to reduce 2n-dimensional original system into n-dimensional averaged ltd stochastic differential equations(SDEs).Reliability function and mean first passage time are obtained by solving the associated backward Kolmogorov equation and Pontryagin *** validity of the proposed procedure is tested by applying it to an example and comparing the numerical results with those from Monte Carlo simulation.

关键词： Reliability fkst passage time Quasi integrable and non-resonant Hamiltonian systems fractional Gauss noise

Composite Vernacular Constructions

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Built Heritage 2019年第4期3卷 26-40页

作者： Miles lewis University of Melbourne MelbourneAustralia

Vernacular building is the building for ordinary people,constrained by the practicalities of environmental conditions and physical materials,and influenced by traditional culture,but not mediated by professional architects and *** of earth and timber,such as wattle and daub,are found in the vernacular in almost every part of the world,but are a source of great confusion to archaeologists and *** are misled by the remains,in which the earth may have survived but the timber usually does *** such as lehmwickel are never recognised in archaeological *** is no common system of naming or classification,and English speakers regularly describe any combination of earth and timber in walling as‘wattle and daub’.Many of these techniques have been changed by the impact of modern technology,notably pole and pug construction(which is often confused with wattle and daub,though it is quite different in principle);this is essentially a 19^(th) century development because it relies upon plentiful and cheap *** purpose of this paper is to establish a common terminology in English,and where possible in other relevant languages,so that misinterpretations are avoided and scholarship can proceed on an orderly basis.

关键词： mixed construction wattle and daub lath and pug lehmwickel pole and pug nails

Role of surfactant in the paradigm of AlI/ARDS

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Acta Pharmacologica Sinica 2003年第12期 164-165页

作者： Jim lewis Canada lawson Health Research Institute/St. Joseph’s Health Center london/Ontario N6A4V2 University of Western Ontario

AlI/ARDS is a devastating complication occurring in critically ill patients, and despite extensive research ettects over the last 30 years, current mortality remains unacceptably high at approxjmately 30% to 40%. Although several different insults can ultimately lead to AlI/ARDS, the clinical definition of this syndrome is relatively simple, and involves commmon physiologic criteria. Indeed, it was these criteria(hypoxemia and decreased lung compliance without heart failure) together with the pathologic similarities to infants with

关键词： Role of surfactant in the paradigm of AlI/ARDS In as on AlI of in