305,939 research outputs found
Design of a smart turning tool with application to in-process cutting force measurement in ultraprecision and micro cutting
In modern micromachining, there is a need to measure and monitor certain machining process parameters in process so as to detect tool wear in real time, to optimize the process parameters setup, and to render the machining process some level of smartness and intelligence. This paper presents the innovative design of a smart turning tool using two pieces of piezoelectric films to measure cutting and feed force in real time. The tool was tested on its performance through the calibration and cutting trials against the commercial dynamometer. The results show the smart turning tool has achieved the performance as designed
Simple choreographies of the planar Newtonian -body Problem
In the -body problem, a simple choreography is a periodic solution, where
all masses chase each other on a single loop. In this paper we prove that for
the planar Newtonian -body problem with equal masses, , there are
at least different main simple choreographies. This
confirms a conjecture given by Chenciner and etc. in \cite{CGMS02}.Comment: 31pages, 6 figures. Refinements in notations and proof
Noise spectra of stochastic pulse sequences: application to large scale magnetization flips in the finite size 2D Ising model
We provide a general scheme to predict and derive the contribution to the
noise spectrum of a stochastic sequence of pulses from the distribution of
pulse parameters. An example is the magnetization noise spectra of a 2D Ising
system near its phase transition. At , the low frequency spectra is
dominated by magnetization flips of nearly the entire system. We find that both
the predicted and the analytically derived spectra fit those produced from
simulations. Subtracting this contribution leaves the high frequency spectra
which follow a power law set by the critical exponents.Comment: 4 pages, 5 figures. We improved text and included a predicted noise
curve in Figure 4. 2 examples from Figure 3 are remove
Plasma Lens Backgrounds at a Future Linear Collider
A 'plasma lens' might be used to enhance the luminosity of future linear
colliders. However, its utility for this purpose depends largely on the
potential backgrounds that may be induced by the insertion of such a device in
the interaction region of the detector. In this note we identify different
sources of such backgrounds, calculate their event rates from the elementary
interaction processes, and evaluate their effects on the major parts of a
hypothetical Next Linear Collider (NLC) detector. For plasma lens parameters
which give a factor of seven enhancement of the luminosity, and using the NLC
design for beam parameters as a reference, we find that the background yields
are fairly high, and require further study and improvements in detector
technology to avoid their impact.Comment: 14 pages incl. 3 figures; contributed to the 4th International
Workshop, Electron-Electron Interactions at TeV Energies, Santa Cruz,
California, Dec. 7 - 9, 2001. To be published in Int.Journ. Mod. Phys.
Industrial capability to chem-mill aluminum alloy 2219 in T-37 and T-87
Procedures and chemical baths were developed for chem-milling aluminum alloy 2219. Using a series of sample etchings, it was found that good etching results could be obtained by using 'white plastic for porcelain repair (toluol, xylol, and petroleum distillates)' on top of cellosolve acetate as resist coatings and ferric chloride as on etchant
Surface optical Raman modes in InN nanostructures
Raman spectroscopic investigations are carried out on one-dimensional
nanostructures of InN,such as nanowires and nanobelts synthesized by chemical
vapor deposition. In addition to the optical phonons allowed by symmetry; A1,
E1 and E2(high) modes, two additional Raman peaks are observed around 528 cm-1
and 560 cm-1 for these nanostructures. Calculations for the frequencies of
surface optical (SO) phonon modes in InN nanostructures yield values close to
those of the new Raman modes. A possible reason for large intensities for SO
modes in these nanostructures is also discussed.Comment: 13 pages, 4 figures, Submitted in Journa
The Nature of Subproton Scale Turbulence in the Solar Wind
The nature of subproton scale fluctuations in the solar wind is an open
question, partly because two similar types of electromagnetic turbulence can
occur: kinetic Alfven turbulence and whistler turbulence. These two
possibilities, however, have one key qualitative difference: whistler
turbulence, unlike kinetic Alfven turbulence, has negligible power in density
fluctuations. In this Letter, we present new observational data, as well as
analytical and numerical results, to investigate this difference. The results
show, for the first time, that the fluctuations well below the proton scale are
predominantly kinetic Alfven turbulence, and, if present at all, the whistler
fluctuations make up only a small fraction of the total energy
Superior removal of arsenic from water with zirconium metal-organic framework UiO-66
10.1038/srep16613Scientific Reports51661
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