6,677 research outputs found
STEP HEIGHT EFFECTS ON LOWER LIMB BIOMECHANICS AND BODY CENTRE OF MASS MOTION DURING ELLIPTICAL EXERCISE
Elliptical exercise (EE) has been shown to be beneficial for the development and maintenance of cardiorespiratory fitness. Despite these benefits, the feet are constrained by pedals to follow an elliptical trajectory, with the possibility of producing disadvantageous joint loads, body instability and potential musculoskeletal overuse injuries (Lu et al., 2007). Proper selection of step height during EE may help reduce these disadvantageous joint loads and instability. The purpose of the study was to study the effects of step height on the lower limb biomechanics and associated body center of mass (COM) motion during EE
A Microcantilever-based Gas Flow Sensor for Flow Rate and Direction Detection
The purpose of this paper is to apply characteristics of residual stress that
causes cantilever beams to bend for manufacturing a micro-structured gas flow
sensor. This study uses a silicon wafer deposited silicon nitride layers,
reassembled the gas flow sensor with four cantilever beams that perpendicular
to each other and manufactured piezoresistive structure on each
micro-cantilever by MEMS technologies, respectively. When the cantilever beams
are formed after etching the silicon wafer, it bends up a little due to the
released residual stress induced in the previous fabrication process. As air
flows through the sensor upstream and downstream beam deformation was made,
thus the airflow direction can be determined through comparing the resistance
variation between different cantilever beams. The flow rate can also be
measured by calculating the total resistance variations on the four
cantilevers.Comment: Submitted on behalf of EDA Publishing Association
(http://irevues.inist.fr/handle/2042/16838
EFFECTS OF STEP LENGTH ON THE BIOMECHANICS OF LOWER LIMBS DURING ELLIPTICAL EXERCISE
Elliptical exercise (EE) has been developed as a low-impact aerobic exercise modality with increased popularity in fitness training and clinical applications over the last decade. During EE, the feet are constrained by pedals to follow an elliptical trajectory, with the possibility of producing disadvantageous joint loads and potential musculoskeletal overuse injuries (Lu et al., 2007). Therefore, proper selection of step length during EE may be helpful for the reduction of these disadvantageous joint loads. The purpose of the study was to study the effects of three different step lengths on biomechanics of the lower limbs during EE
Magnetic oxide semiconductors
Magnetic oxide semiconductors, oxide semiconductors doped with transition
metal elements, are one of the candidates for a high Curie temperature
ferromagnetic semiconductor that is important to realize semiconductor
spintronics at room temperature. We review in this paper recent progress of
researches on various magnetic oxide semiconductors. The magnetization,
magneto-optical effect, and magneto-transport such as anomalous Hall effect are
examined from viewpoint of feasibility to evaluate the ferromagnetism. The
ferromagnetism of Co-doped TiO2 and transition metal-doped ZnO is discussed.Comment: 26 pages, 5 tables, 6 figure
The BCS-like gap in superconductor SmFeAsO_0.85F_0.15
Since the discovery of superconductivity in the cuprates two decades ago, it
has been firmly established that the CuO_2 plane is consequential for high T_C
superconductivity and a host of other very unusual properties. A new family of
superconductors with the general composition of LaFeAsO_(1-x)F_x has recently
been discovered but with the conspicuous lacking of the CuO_2 planes, thus
raising the tantalizing questions of the different pairing mechanisms in these
oxypnictide superconductors. Intimately related to pairing in a superconductor
are the superconducting gap, its value, structure, and temperature dependence.
Here we report the observation of a single gap in the superconductor
SmFeAsO_0.85F_0.15 with T_C = 42 K as measured by Andreev spectroscopy. The gap
value of 2Delta = 13.34+/-0.3 meV gives 2Delta/k_BT_C = 3.68, close to the BCS
prediction of 3.53. The gap decreases with temperature and vanishes at T_C in a
manner consistent with the Bardeen-Cooper-Schrieffer (BCS) prediction but
dramatically different from that of the pseudogap behavior in the cuprate
superconductors. Our results clearly indicate a nodeless gap order parameter,
which is nearly isotropic in size across different sections of the Fermi
surface, and are not compatible with models involving antiferromagnetic
fluctuations, strong correlations, t-J model, and the like, originally designed
for cuprates.Comment: 8 pages, 3 figure
Zn-doping effect on the magnetotransport properties of Bi_{2}Sr_{2-x}La_{x}CuO_{6+\delta} single crystals
We report the magnetotransport properties of
Bi_{2}Sr_{2-x}La_{x}Cu_{1-z}Zn_{z}O_{6+\delta} (Zn-doped BSLCO) single crystals
with z of up to 2.2%. Besides the typical Zn-doping effects on the in-plane
resistivity and the Hall angle, we demonstrate that the nature of the
low-temperature normal state in the Zn-doped samples is significantly altered
from that in the pristine samples under high magnetic fields. In particular, we
observe nearly-isotropic negative magnetoresistance as well as an increase in
the Hall coefficient at very low temperatures in non-superconducting Zn-doped
samples, which we propose to be caused by the Kondo scattering from the local
moments induced by Zn impurities.Comment: 4 pages, 4 figures, final version (one reference added), published in
Phys. Rev.
Generating scalable graph states in an atom-nanophotonic interface
Scalable graph states are essential for measurement-based quantum computation
and many entanglement-assisted applications in quantum technologies. Generation
of these multipartite entangled states requires a controllable and efficient
quantum device with delicate design of generation protocol. Here we propose to
prepare high-fidelity and scalable graph states in one and two dimensions,
which can be tailored in an atom-nanophotonic cavity via state carving
technique. We propose a systematic protocol to carve out unwanted state
components, which facilitates scalable graph states generations via adiabatic
transport of a definite number of atoms in optical tweezers. An analysis of
state fidelity is also presented, and the state preparation probability can be
optimized via multiqubit state carvings and sequential single-photon probes.
Our results showcase the capability of an atom-nanophotonic interface for
creating graph states and pave the way toward novel problem-specific
applications using scalable high-dimensional graph states with stationary
qubits.Comment: 5 figures with supplemental materia
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