1,591 research outputs found
ARCHERY TRAINING IMPROVE POSTURAL CONTROL IN YOUNG CHILDREN
Exercise training might be beneficial for postural control (PC) during exercise and daily activities. The purpose of the study was to examine the effects of an eight-week archery training program on PC in young children during the standard, aiming, and archery shooting standing posture
3D Computer Modeling Analysis of the Surface Area and Thread Volume of the Common Sliding Hip Screw
Introduction: The Sliding Hip Screw (SHS) is a tried and tested method used to treat intertrochanteric hip fractures. Lag screw cut-out is a major complication of SHS fixation and accepted risk factors are often re-evaluated. We aim to demonstrate a new hypothesis of cut-out using 3D reconstructive modelling. We propose that the risk of cut-out is much greater in lag screws with a smaller thread surface area and larger thread volume.
Method: The four commonly used SHS lag screw systems (Biomet, Synthes, Stryker and Smith & Nephew) were CT scanned and the images processed and turned into 3D computer models for further analysis.
Results: There were significan differences between the surface area and thread volumes of the lag screws between manufacturers ranging from 67.0mm2 - 347.4 mm2 and 166.376mm3 - 225.687mm3 respectively.
Discussion: Assuming the consistency of bone is equal, we propose that the risk of cut-out is much greater in lag screws with a smaller surface area to thread volume ratio (SA:TV). The reamer design of lag screws is also discussed.
Conclusion: Although there are many non-modifiable risk factors that contribute to screw cut-out, selecting the right raw materials for SHS fixation will have a favorable impact on the overall risk
Web-enabled, Real-time, Quality Assurance for Machining Production Systems
AbstractIn order to maintain the close control of production quality, frequent measurement and process parameter adjustments are desirable. In the discrete parts industry, part inspection is intended to be a metric for the process quality but quality control is typically done long after the part has been machined. The long latency between machining and quality assessment makes it difficult to incorporate quality feedback into production. Quality assurance relies on continuous real–time quality feedback, which is not a complex concept. However, the collection and representation of the necessary process data and quality measurement data is challenging. This paper discusses Web-enabled, real-time quality data and statistics based on the integration of two manufacturing open specifications: MTConnect and Quality Measurement Results (QMResults). A pilot implementation that integrates the two technologies and produces Web-enabled, real-time quality results in a standard XML representation from Computer Numerical Control (CNC) machine tool inspections will be discussed
Field evaluation of the bioefficacy of diflubenzuron (Dimilin (R)) against container-breeding Aedes sp mosquitoes
The inhibitory activity of diflubenzuron, a chitin synthesis inhibitor, on the ecdysis of Aedes sp. larvae was evaluated in earthen jars and automobile tires. Two formulations of diflubenzuron were used in this study: Dimilin (R) WP (wettable powder), 25 and Dimilin (R) GR (granular), 2. The equivalent rate of 25 g/ha, 50 g/ha and 100 g/ha active ingredients for both WP and GR formulations were used in this study. Generally, at the higher dosage of 100 g/ha, both formulations were more effective against Aedes mosquitoes. On the whole, the WP formulation appeared to perform better than the GR formulation in terms of residual activity
Magnetotransport Mechanisms in Strongly Underdoped YBa_2Cu_3O_x Single Crystals
We report magnetoresistivity measurements on strongly underdoped YBa_2Cu_3O_x
(x=6.25, 6.36) single crystals in applied magnetic fields H || c-axis. We
identify two different contributions to both in-plane and out-of-plane
magnetoresistivities. The first contribution has the same sign as the
temperature coefficient of the resistivity \partial ln(\rho_i)/\partial T
(i={c,ab}). This contribution reflects the incoherent nature of the
out-of-plane transport. The second contribution is positive, quadratic in
field, with an onset temperature that correlates to the antiferromagnetic
ordering.Comment: 4 pages, 3 figure
Cardy-Verlinde formula of Kehagias-Sfetsos black hole
In this paper, we have shown that the entropy of the Kehagias-Sfetsos black
hole in Hoava-Lifshitz (HL) gravity can be expressed by the
Cardy-Verlinde formula. The later is supposed to be an entropy formula of
conformal field theory in any dimension.Comment: 10 pages, accepted by IJT
Charmonium Decay Physics
Recent experimental results on the decays of charmonium, together with
related physics issues, are reviewed. Some future prospects are described.Comment: 8 pages, latex, no figures. Invited talk at the 8th International
Conference on Hadron Spectroscopy (Hadron99), Beijing, 24-28 august, 1999; to
appear in Proceeding
Measurement of the Intrinsic Radiopurity of Cs-137/U-235/U-238/Th-232 in CsI(Tl) Crystal Scintillators
The inorganic crystal scintillator CsI(Tl) has been used for low energy
neutrino and Dark Matter experiments, where the intrinsic radiopurity is an
issue of major importance. Low-background data were taken with a CsI(Tl)
crystal array at the Kuo-Sheng Reactor Neutrino Laboratory. The pulse shape
discrimination capabilities of the crystal, as well as the temporal and spatial
correlations of the events, provide powerful means of measuring the intrinsic
radiopurity of Cs-137 as well as the U-235, U-238 and Th-232 series. The event
selection algorithms are described, with which the decay half-lives of Po-218,
Po-214, Rn-220, Po-216 and Po-212 were derived. The measurements of the
contamination levels, their concentration gradients with the crystal growth
axis, and the uniformity among different crystal samples, are reported. The
radiopurity in the U-238 and Th-232 series are comparable to those of the best
reported in other crystal scintillators. Significant improvements in
measurement sensitivities were achieved, similar to those from dedicated
massive liquid scintillator detector. This analysis also provides in situ
measurements of the detector performance parameters, such as spatial
resolution, quenching factors, and data acquisition dead time.Comment: 28 pages, 12 figure
Formation of two-dimensional weak localization in conducting Langmuir-Blodgett films
We report the magnetotransport properties up to 7 T in the organic highly
conducting Langmuir-Blodgett(LB) films formed by a molecular association of the
electroactive donor molecule bis(ethylendioxy)tetrathiafulvalene (BEDO-TTF) and
stearic acid CH(CH)COOH. We show the logarithmic decrease of dc
conductivity and the negative transverse magnetoresistance at low temperature.
They are interpreted in the weak localization of two-dimensional (2D)
electronic system based on the homogeneous conducting layer with the molecular
size thickness of BEDO-TTF. The electronic length with phase memory is given at
the mesoscopic scale, which provides for the first time evidence of the 2D
coherent charge transport in the conducting LB films.Comment: 5 pages, 1 Table and 5 figure
Random field sampling for a simplified model of melt-blowing considering turbulent velocity fluctuations
In melt-blowing very thin liquid fiber jets are spun due to high-velocity air
streams. In literature there is a clear, unsolved discrepancy between the
measured and computed jet attenuation. In this paper we will verify numerically
that the turbulent velocity fluctuations causing a random aerodynamic drag on
the fiber jets -- that has been neglected so far -- are the crucial effect to
close this gap. For this purpose, we model the velocity fluctuations as vector
Gaussian random fields on top of a k-epsilon turbulence description and develop
an efficient sampling procedure. Taking advantage of the special covariance
structure the effort of the sampling is linear in the discretization and makes
the realization possible
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