3,051 research outputs found
Animal breeding in organic farming
After a general introduction into the available breeding techniques for animal breeding and an overview of the organic principles, points for discussion are identified and scenario's for organically accepted breeding methods are discussed
Optimizing the Post Sandvik Nanoflex material model using inverse optimization and the finite element method
This article describes an inverse optimization method for the Sandvik Nanoflex steel in cold forming\ud
processes. The optimization revolves around measured samples and calculations using the Finite Element\ud
Method. Sandvik Nanoflex is part of the group of meta-stable stainless steels. These materials are characterized\ud
by a good corrosion resistance, high strength, good formability and crack resistance. In addition, Sandvik\ud
Nanoflex has a strain-induced transformation and, depending on austenising conditions and chemical composition,\ud
a stress-assisted transformation can occur. The martensite phase of this material shows a substantial aging\ud
response. The inverse optimization is a sub-category of the optimization techniques. The inverse optimization\ud
method uses a top down approach, as the name implies. The starting point is a prototype state where the current\ud
state is to converge on. In our experiment the test specimen is used as prototype and a calculation result as\ud
current state. The calculation is then adapted so that the result converges towards the test example. An iterative\ud
numerical optimization algorithm controls the adaptation. For the inverse optimization method two parameters\ud
are defined: shape of the product and martensite profile. These parameters are extracted from both calculation\ud
and test specimen, using Fourier analysis and integrals. An optimization parameter is then formulated from\ud
the extracted parameters. The method uses this optimization parameter to increase the accuracy of ”The Post”\ud
material model for Sandvik Nanoflex. [1] The article will describe a method to optimize material models, using\ud
a combination practical experiments, Finite Element Method and parameter extraction
Use of the NESS Handmaster to restore handfunction in tetraplegia: clinical experiences in ten patients
Objective: To explore possible functional effects of the Handmaster in tetraplegia and to determine suitable patients for the system. \ud
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Patients: Patients with a cervical spinal cord injury between C4 and C6, motor group 0-3. Important selection criteria were a stable clinical situation and the absence of other medical problems and complications. \ud
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Design: Ten patients were consecutively selected from the in- and outpatient department of a large rehabilitation hospital in The Netherlands. Each patient was fitted with a Handmaster by a qualified therapist and underwent muscle strength and functional training for at least 2 months. \ud
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Methods: Functional evaluation comprised the performance of a defined set of tasks and at least one additional task as selected by patients themselves. Tasks were performed both with and without the Handmaster. Finally, patients were asked for their opinion on Handmaster use as well as their willingness to future use. \ud
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Results: In six patients a stimulated grasp and release with either one or both grasp modes (key- and palmar pinch) of the Handmaster was possible. Four patients could perform the set of tasks using the Handmaster, while they were not able to do so without the Handmaster. Eventually, one patient continued using the Handmaster during ADL at home. \ud
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Conclusion: The Handmaster has a functional benefit in a limited group of patients with a C5 SCI motor group 0 and 1. Suitable patients should have sufficient shoulder and biceps function combined with absent or weak wrist extensors. Though functional use was the main reason for using the Handmaster, this case series showed that therapeutic use can also be considered. \ud
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Appreciations of teaching methods across cultures:Lessons learned from international students
Partial-measurement back-action and non-classical weak values in a superconducting circuit
We realize indirect partial measurement of a transmon qubit in circuit
quantum electrodynamics by interaction with an ancilla qubit and projective
ancilla measurement with a dedicated readout resonator. Accurate control of the
interaction and ancilla measurement basis allows tailoring the measurement
strength and operator. The tradeoff between measurement strength and qubit
back-action is characterized through the distortion of a qubit Rabi oscillation
imposed by ancilla measurement in different bases. Combining partial and
projective qubit measurements, we provide the solid-state demonstration of the
correspondence between a non-classical weak value and the violation of a
Leggett-Garg inequality.Comment: 5 pages, 4 figures, and Supplementary Information (8 figures
Probing dynamics of an electron-spin ensemble via a superconducting resonator
We study spin relaxation and diffusion in an electron-spin ensemble of
nitrogen impurities in diamond at low temperature (0.25-1.2 K) and polarizing
magnetic field (80-300 mT). Measurements exploit mode- and
temperature-dependent coupling of hyperfine-split sub-ensembles to the
resonator. Temperature-independent spin linewidth and relaxation time suggest
that spin diffusion limits spin relaxation. Depolarization of one sub-ensemble
by resonant pumping of another indicates fast cross-relaxation compared to spin
diffusion, with implications on use of sub-ensembles as independent quantum
memories.Comment: 5 pages, 5 figures, and Supplementary Information (2 figures
Visuospatial coding as ubiquitous scaffolding for human cognition
For more than 100 years we have known that the visual field is mapped onto the surface of visual cortex, imposing an inherently spatial reference frame on visual information processing. Recent studies highlight visuospatial coding not only throughout visual cortex, but also brain areas not typically considered visual. Such widespread access to visuospatial coding raises important questions about its role in wider cognitive functioning. Here, we synthesise these recent developments and propose that visuospatial coding scaffolds human cognition by providing a reference frame through which neural computations interface with environmental statistics and task demands via perception–action loops
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