4181   New method of determination of the I-V characteristics of negative differential conductance devices New method of determination of the I-V characteristics of negative differential conductance devices    1992 There has been increased interest in the study of resonant tunneling quantum well devices due to the fact that the characteristics of these devices can be engineered to have properties for very high-speed applications. In particular, their ability to exhibit negative differential conductance (NDC) regions lead to their potential use as gain elements and offers a new opportunity for circuit design. In this paper, the NDC portion of the I-V characteristic of a NDC device is mapped out by measuring... 查看全文

4182   Science and intractable conflict Science and intractable conflict    2007 Using illustrative examples, this article describes how science and other types of information often are used in an attempt to settle Conflict. Expectations for science to arbitrate differences may be misplaced, however, and such misuse of science can aggravate and exacerbate Conflict. Instead, effective resolution may be facilitated by focusing on facts that matter, acknowledging the value of varied sorts and sources of information, and recognizing scientific uncertainty. 查看全文

4183   Mathematical analysis of the evaporative process of a new technological treatment of rising damp in historic buildings Mathematical analysis of the evaporative process of a new technological treatment of rising damp in historic buildings    2010 The treatment of rising damp in historic buildings walls is very complex, due to the thickness and heterogeneity of those walls. The traditionally techniques used to deal with this kind of problem (such as watertight barriers, injection of hydrofuge products, etc.) show, sometimes, to be ineffective, justifying the need to find a new approach.Experimental studies in the area of rising damp validate the effectiveness of a new treatment technique applied to the walls of old buildings. The results ... 查看全文

4184   Inorganic nuclear content as an index of tumour radiosensitivity† Inorganic nuclear content as an index of tumour radiosensitivity†    2005 查看全文

4185   New bounds for the solutions of second order linear differential equations New bounds for the solutions of second order linear differential equations    2010 This paper presents a new method to construct explicit bounds for the solutions of second order linear differential equations of the type [p (x) y′ (x)]′ + q (x) y (x) = 0,p (x), q (x) > 0, x > x0, which complements the method described in recent papers of the authors. The method lies in the use of Beesack's version of Opial's inequality. Some results on asymptotics of the solution for the case p (x) = 1 are also included. © 2009 Elsevier Ltd. All rights reserved. 查看全文

4186   New family of highly linear CMOS transconductors based on the current tail differential pair New family of highly linear CMOS transconductors based on the current tail differential pair    1999 A new family of linear differential transconductors based on the current tail differential pair is presented. The proposed transconductor employs MOS transistors operating in the saturation region. It is shown that the proposed transconductors offer superior linearity and wider range in addition to the simplicity and high frequency response, which characterizes the current tail differential pair transconductor. PSpice simulation results are given. 查看全文

4187   Development of a solution method for the differential equations arising in the biosphere module of the BNFL's suite of codes MONDRIAN Development of a solution method for the differential equations arising in the biosphere module of the BNFL's suite of codes MONDRIAN    2002 British Nuclear Fuels plc owns and operates the near-surface Drigg disposal facility for low level radioactive waste. The long-term performance of the site is modelled by a suite of computer codes called MONDRIAN. One of the modules of MONDRIAN deals with the transport of radionuclides through the environment, and this paper reports on the current status of this module (BIOS). We derive the basic set of working equations from first principles and show clearly how the approximate nature of the fi... 查看全文

4188   Enterophilins, a New Family of Leucine Zipper Proteins Bearing a B30.2 Domain and Associated with Enterocyte Differentiation Enterophilins, a New Family of Leucine Zipper Proteins Bearing a B30.2 Domain and Associated with Enterocyte Differentiation    2001 Enterocyte terminal differentiation occurs at the crypt-villus junction through the transcriptional activation of cell-specific genes, many of which code for proteins of the brush border membrane such as intestinal alkaline phosphatase, sucrase-isomaltase, or the microvillar structural protein villin. Several studies have shown that this sharp increase in specific mRNA levels is intimately associated with arrest of cell proliferation. We isolated several clones from a guinea pig intestine cDNA l... 查看全文

4189   A new class of scale free solutions to linear ordinary differential equations and the universality of the golden mean (√5 - 1)/2 = 0.618033... A new class of scale free solutions to linear ordinary differential equations and the universality of the golden mean (√5 - 1)/2 = 0.618033...    2003 A new class of finitely differentiable scale free solutions to the simplest class of ordinary differential equations is presented. Consequently, the real number set gets replaced by an extended physical set, each element of which is endowed with an equivalence class of infinitesimally separated neighbours in the form. of random fluctuations. We show how a sense of time and evolution is intrinsically defined by the infinite continued fraction of the golden mean irrational number (√5 - 1)/2,... 查看全文

4190   The Brent Spar Controversy: An Example of Risk Communication Gone Wrong The Brent Spar Controversy: An Example of Risk Communication Gone Wrong Karl Dake    2006 This perspective piece uses the theories and ideas of risk communication to shed light on the reasons why the proposed dumping of Brent Spar in the U.K. offshore waters caused such an international uproar. We postulate that the Brent Spar crisis is a classic example of risk communication gone wrong. Had the sinking of the storage buoy not been amplified by the media and the environmental group Greenpeace, and had not the U.K. Government nor Shell come across as distrustful it would probably have... 查看全文

4191   A time delay model for the diffusion of a new technology A time delay model for the diffusion of a new technology    2012 In this paper, we propose a mathematical model with time delay to describe the process of diffusion of a new technology. This model is suitable for modeling diffusion processes of all those technologies that require great initial investments and public subsidies, such as technologies used for producing renewable energy. We consider external factors, such as the government policy and the production costs, that influence the decision of adoption of the new technology. We also consider the internal... 查看全文

4192   Discrete first- and second-order adjoints and automatic differentiation for the sensitivity analysis of dynamic models Discrete first- and second-order adjoints and automatic differentiation for the sensitivity analysis of dynamic models    2010 We describe the use of first- and second-order tangent-linear and adjoint models of the residual of linear-implicit autonomous differential algebraic systems in the context of an extrapolated Euler scheme. The derivative code compiler dcc is applied to a C-implementation of the residual to get first derivative code. Second-(and higher-)order derivative models are obtained by reapplication of dcc to its own output. The resulting solver serves as a first proof of concept of a new platform. for sou... 查看全文

4193   A note on the controllability and the observability of fractional dynamical systems A note on the controllability and the observability of fractional dynamical systems    2006 In this paper, we give some new results on the controllability and the observability of linear dynamical systems with a fractional derivative of order α, where α is a non integer number.We show that the observability and the controllability Gramians, recently introduced for a fractional order system, are solutions of fractional differential Lyapunov equations, thus generalizing the classical result for the integer case (α = 1). Our results can be considered as a generalization ... 查看全文

4194   Improvement in the morphology of micro-arc oxidised titanium surfaces: A new process to increase osteoblast response Improvement in the morphology of micro-arc oxidised titanium surfaces: A new process to increase osteoblast response    2010 This study describes a method for combining sandblast-acid etching and micro-arc oxidation to optimise titanium implant surfaces, and examines the effects of these surfaces on osteoblast response. Titanium discs were grouped as: micro-arc oxidised (MAO), sandblast-acid etched and micro-arc oxidised (MAO-SA), micro-arc oxidised and heated (MAO-HT), and untreated smooth surface. The combination of sandblast-acid etching and micro-arc oxidation in the MAO-SA group created an average surface roughne... 查看全文

4195   A new generalized algebra method and its application in the (2 + 1) dimensional Boiti-Leon-Pempinelli equation A new generalized algebra method and its application in the (2 + 1) dimensional Boiti-Leon-Pempinelli equation    2007 In the present paper, some types of general solutions of a first-order nonlinear ordinary differential equation with six degree are given and a new generalized algebra method is presented to find more exact solutions of nonlinear differential equations. As an application of the method and the solutions of this equation, we choose the (2 + 1) dimensional Boiti Leon Pempinelli equation to illustrate the validity and advantages of the method. As a consequence, more new types and general solutions a... 查看全文

4196   On new developments in the physics of positron swarms On new developments in the physics of positron swarms    2010 Recently a new wave of swarm studies of positrons was initiated based on more complete scattering cross section sets. Initially some interesting and new physics was discovered, most importantly negative differential conductivity (NDC) that occurs only for the bulk drift velocity while it does not exist for the flux property. However the ultimate goal was to develop tools to model positron transport in realistic applications and the work that is progressing along these lines is reviewed here. It ... 查看全文

4197   A new iterative solver for the time-harmonic wave equation A new iterative solver for the time-harmonic wave equation    2006 The time-harmonic wave equation, also known as the Helmholtz equation, is obtained if the constant-density acoustic wave equation is transformed from the time domain to the frequency domain. Its discretization results in a large, sparse, linear system of equations. In two dimensions, this system can be solved efficiently by a direct method. In three dimensions, direct methods cannot be used for problems of practical sizes because the computational time and the amount of memory required become to... 查看全文

4198   New exact Jacobi elliptic functions solutions for the generalized coupled Hirota-Satsuma KdV system New exact Jacobi elliptic functions solutions for the generalized coupled Hirota-Satsuma KdV system    2010 In this paper, an generalized Jacobi elliptic functions expansion method with computerized symbolic computation is used for constructing more new exact Jacobi elliptic functions solutions of the generalized coupled Hirota-Satsuma KdV system. As a result, eight families of new doubly periodic solutions are obtained by using this method, some of these solutions are degenerated to solitary wave solutions and triangular functions solutions in the limit cases when the modulus of the Jacobi elliptic f... 查看全文

4199   A revival of the landscape paradigm: Large scale data harvesting provides access to fitness landscapes A revival of the landscape paradigm: Large scale data harvesting provides access to fitness landscapes Peter Schuster    2012 查看全文

4200   NEW METHOD FOR THE ESTIMATION OF PARAMETERS IN DIFFERENTIAL EQUATIONS. NEW METHOD FOR THE ESTIMATION OF PARAMETERS IN DIFFERENTIAL EQUATIONS.    1974 A new objective function for estimating parameters in differential equations, based upon a weighted least squares criterion for the residuals of these equations, is presented. The use of Lobatto quadrature in combination with the collocation technique reduces the original problem to one of minimizing a simple algebraic expression with respect to a series of unknowns. The method can be applied to different types of differential equations as shown by a series of examples and leads to very good est... 查看全文

4201   Continental slope reconstruction after a giant mass failure, the example of the Matakaoa Margin, New Zealand Continental slope reconstruction after a giant mass failure, the example of the Matakaoa Margin, New Zealand    2010 During the Pleistocene, the Matakaoa Debris Avalanche (MDA) removed ~ 430 km3 of material and formed a 50 km-long re-entrant in the Matakaoa margin, offshore East Cape, New Zealand. In this study, we examine the post-avalanche processes of continental slope reconstruction via the analysis of bathymetry, seismic-reflection data and one sediment core. The study reconstructs the post-MDA history of the Matakaoa margin and reveals how the giant mass-transport event laid the foundation for present va... 查看全文

4202   Windscale fallout—A primer for the age of nuclear controversy, Ian Breach, Penguin Books Ltd., Hardmondsworth, England, 1978. No. of pages: 192. Price: £0.90 Windscale fallout—A primer for the age of nuclear controversy, Ian Breach, Penguin Books Ltd., Hardmondsworth, England, 1978. No. of pages: 192. Price: £0.90 Jonathan Goldstein    2007 查看全文

4203   Physical volcanology of the mafic segment of the subaqueous New Senator caldera, Abitibi greenstone belt, Quebec, Canada Physical volcanology of the mafic segment of the subaqueous New Senator caldera, Abitibi greenstone belt, Quebec, Canada    2008 Archean calderas provide valuable insight into internal geometries of subaqueous calderas. The New Senator caldera, Abitibi greenstone belt, Canada, is an Archean example of a subaqueous nested caldera with a basal stratigraphy dominated by gabbro-diorite dykes and sills, ponded magmas and basalt and andesite lava flows. The aim of our study is to focus on the use of physical volcanology to differentiate between the various mafic units found at the base of the New Senator caldera. Differentiatio... 查看全文

4204   National Climate Change Conference in South Africa National Climate Change Conference in South Africa Kiaran Kirk    2006 查看全文

4205   Nematodes from the Strait of Magellan and the Beagle Channel (Chile): Description of four new species of the Comesomatidae Nematodes from the Strait of Magellan and the Beagle Channel (Chile): Description of four new species of the Comesomatidae    1998 Four nematode species of the Comesomatidae from the Strait of Magellan and the Beagle Channel, Chile, are described as new to science. Comesoma hermani n. sp. can be separated from similar species, Comesoma bermudense Jensen & Gerlach, 1977, Comesoma minimum Chitwood, 1937 and Comesoma chilense Jensen & Gerlach, 1977 by the difference of body length, cephalic setae length, the ratio of the subcephalic setae to cephalic setae length and the ratio of spicule to anal body diameter. Dorylaimopsis ma... 查看全文

4206   New vision of the Shuaiba at a regional scale New vision of the Shuaiba at a regional scale    2005 The regional integration of well data, seismic observations and published information from the southern part of the Arabian Peninsula has led to a breakthrough in understanding the stratigraphy and depositional history of the Shuaiba and in extracting implications regarding hydrocarbon prospectivity. The Shuaiba Formation is composed of system tracts from two supersequences, and the following subdivision is proposed: The Lower Shuaiba contains a TST and HST of a supersequence (Early Aptian, earl... 查看全文

4207   Some new types of multisoliton solutions for the (2+1)-dimensional higher-order Broer-Kaup system Some new types of multisoliton solutions for the (2+1)-dimensional higher-order Broer-Kaup system    2004 In this paper, by improving some procedure of the homogeneous balance method, some new types of multisoliton solutions for the (2+1)-dimensional higher-order Broer-Kaup system are obtained. © 2003 Elsevier Inc. All rights reserved. 查看全文

4208   A new approach to the modeling and analysis of fracture through extension of continuum mechanics to the nanoscale A new approach to the modeling and analysis of fracture through extension of continuum mechanics to the nanoscale    2010 In this paper we focus on the analysis of the partial differential equations arising from a new approach to modeling brittle fracture based on an extension of continuum mechanics to the nanoscale. It is shown that ascribing constant surface tension to the fracture surfaces and using the appropriate crack surface boundary condition given by the jump momentum balance leads to a sharp crack opening profile at the crack tip but predicts logarithmically singular crack tip stress. However, a modified ... 查看全文

4209   The handling surface: A new perspective in vehicle dynamics The handling surface: A new perspective in vehicle dynamics    2007 The problem of describing the understeer-oversteer behaviour of a general vehicle, such as one with locked differential or tandem rear axle, is addressed taking a new perspective. The well-known handling diagram and the associated classical understeer gradient may be inadequate, mainly because they are no longer unique. The new concept of handling surface and a new definition of understeer gradient, which is indeed the gradient of the handling surface and hence a vector, are presented. It is als... 查看全文

4210   Identifying the characteristic impedance of the drill bit based on differential evolution algorithm Identifying the characteristic impedance of the drill bit based on differential evolution algorithm    2012 By establishing the state equations parameterized with transmission coefficient for the drill bit's incident waves and reflection waves, the parameter identification of the characteristics impedance of the drill bit was formulated as a nonlinear global optimization problem. A new method based on differential evolution was proposed in order to solve the global optimization problem. The effectiveness of the proposed method was investigated by using experimental data of three drill bits with variab... 查看全文

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