10,678 research outputs found
Learning algorithms for multi-class pattern classification and problems associated with on-line handwritten character recognition
On-line handwritten alphanumeric character recognition system and learning algorithm for multiclass pattern classificatio
A two-dimensional ultrasonic model study of compressional and shear-wave diffraction patterns produced by a circular cavity
Diffraction patterns of compressional (P) and shear (SV) waves produced by a circular hole were experimentally obtained on a two-dimensional ultrasonic model. The shapes of the Fresnel patterns were found to depend on, 1) α/λ, the ratio of the radius of the cylinder to the wavelength; and, 2) the wave type. The transitional zone between the illuminated and the shadow regions broadens, and the half-amplitude point shifts away from the geometrical shadow as α/λ decreases. For comparable α/λ, the shadow boundary of the SV wave appears to start much earlier than that of the P wave
Buckling without bending: a new paradigm in morphogenesis
A curious feature of organ and organoid morphogenesis is that in certain
cases, spatial oscillations in the thickness of the growing "film" are
out-of-phase with the deformation of the slower-growing "substrate," while in
other cases, the oscillations are in-phase. The former cannot be explained by
elastic bilayer instability, and contradict the notion that there is a
universal mechanism by which brains, intestines, teeth, and other organs
develop surface wrinkles and folds. Inspired by the microstructure of the
embryonic cerebellum, we develop a new model of 2d morphogenesis in which
system-spanning elastic fibers endow the organ with a preferred radius, while a
separate fiber network resides in the otherwise fluid-like film at the outer
edge of the organ and resists thickness gradients thereof. The tendency of the
film to uniformly thicken or thin is described via a "growth potential".
Several features of cerebellum, +blebbistatin organoid, and retinal fovea
morphogenesis, including out-of-phase behavior and a film thickness amplitude
that is comparable to the radius amplitude, are readily explained by our simple
analytical model, as may be an observed scale-invariance in the number of folds
in the cerebellum. We also study a nonlinear variant of the model, propose
further biological and bio-inspired applications, and address how our model is
and is not unique to the developing nervous system.Comment: version accepted by Physical Review
Do bank bailouts have a silver lining?
__Abstract__
Much criticism was levelled at the USA’s Troubled Asset Relief
Program (TARP) at the time it was announced in the autumn of
2008. Many of its opponents argued that not a penny of taxpayer
money should have been spent on shoring up US banks. But
were they right
Corporate social responsibility reporting in China: political, social and corporate influences
This paper explores the main drivers of CSR and its reporting for large Chinese listed companies, and identifies the key institutional pressures and stakeholder influences that shape CSR and its reporting. The data were collected through interviews with managers from large listed Chinese companies. Our findings reveal how the Chinese government uses social organisations and social intermediaries to facilitate and mediate CSR and its reporting to meet changing societal expectations across regions, while ensuring that companies remain responsive to the expectations of international stakeholders. We find that CSR and its reporting help companies gain political legitimacy domestically, while retaining their legitimacy in global markets. Companies co-operate with social organisations and social intermediaries actively and continuously. This helped companies secure political legitimacy with the government, while helping officials maintain their social legitimacy. Our findings on regional differences support the idea that relations between Chinese business and society have a fundamental effect on CSR and its reporting
At the limits of ‘Capability’: The sexual and reproductive health of women migrant workers in Malaysia
Despite the centrality of sexual and reproductive health (SRH) to UN Sustainable Development Goals (SDGs), women migrant workers in Malaysia face an environment inimical to their SRH needs. Drawing on qualitative case study material, we present the first empirical application of the Capability Approach (CA) to explore the reproductive health needs of women migrant workers in a developing country, offering an original analysis of the capability for SRH of these women. Specifically, we explore the resources available to them; their opportunities and freedoms (‘capabilities’); and factors which mediate transformation of resources into capability sets (‘conversion factors’). While SRH information and healthcare is notionally available, women migrant workers face multiple challenges in converting resources into functionings, constraining the achievement of capability for SRH. Challenges include language barriers, personal beliefs, power relations between workers and employers and the consequences of current migration policy. We consider the scale of the challenges facing these women in securing SRH rights, the difficulties of operationalising the CA within such a setting, and the implications of our findings for the adequacy of the CA in supporting marginalised populations
Density dependence of spin relaxation in GaAs quantum well at room temperature
Carrier density dependence of electron spin relaxation in an intrinsic GaAs
quantum well is investigated at room temperature using time-resolved circularly
polarized pump-probe spectroscopy. It is revealed that the spin relaxation time
first increases with density in the relatively low density regime where the
linear D'yakonov-Perel' spin-orbit coupling terms are dominant, and then tends
to decrease when the density is large and the cubic D'yakonov-Perel' spin-orbit
coupling terms become important. These features are in good agreement with
theoritical predictions by L\"u {\em et al.} [Phys. Rev. B {\bf 73}, 125314
(2006)]. A fully microscopic calculation based on numerically solving the
kinetic spin Bloch equations with both the D'yakonov-Perel' and the
Bir-Aronov-Pikus mechanisms included, reproduces the density dependence of spin
relaxation very well.Comment: 4 pages, 2 figures, Europhys. Lett., in pres
Flexural behaviour of hybrid FRP-concrete-steel double skin tubular members
This paper presents the results of an experimental study on the flexural behavior of a new type of hybrid FRP-concrete-steel member as well as results from a corresponding theoretical model based on the plane section assumption and the fiber element approach. This new type of hybrid member is in the form of a double-skin tube, composed of a steel inner tube and an FRP outer tube with a concrete infill between the two tubes, and may be employed as columns or beams. The parameters examined in this study include the section configuration, the concrete strength, and the thicknesses of the steel tube and the FRP tube, respectively. The results presented in this paper show that these hybrid beams have a very ductile response because the compressive concrete is confined by the FRP tube and the steel tube provides ductile longitudinal reinforcement. The beams\u27 flexural response, including the flexural stiffness, ultimate load, and cracking, can be substantially improved by shifting the inner steel tube toward the tension zone or by providing FRP bars as additional longitudinal reinforcement. The predictions from the theoretical model are in reasonably close agreement with the test results. Differences between the test and predicted results arise from factors not considered in the theoretical model, including the existence of a strain gradient in the confined concrete, concentrations of cracks and the slips between the concrete and the two tubes; these are issues to be accounted for in the development of a more accurate model in the future
An Exploratory Study of Lecturers' Views of Out-of-class Academic Collaboration Among Students
This article reports an exploratory study of lecturers' perceptions of out-of-class academic collaboration (OCAC) among students at a large Singapore university. Two types of OCAC were investigated: collaboration initiated by students, e.g., groups decide on their own to meet to prepare for exams, and collaboration required by teachers, e.g., teachers assign students to do projects in groups. Data were collected via one-on-one interviews with 18 faculty members from four faculties at the university. Findings suggest that OCAC, especially of a teacher-required kind, is fairly common at the university. Faculty members' views on factors affecting the success of OCAC are discussed for the light they might shed on practices to enhance the effectiveness of OCAC
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