7,870 research outputs found
Automated Array Assembly Task In-depth Study of Silicon Wafer Surface Texturizing
Several aspects of silicon wafer surface texturizing were studied. A low cost cleaning method that utilizes recycled Freon in an ultrasonic vapor degreaser to remove organic and inorganic contaminants from the surface of silicon wafers as received from silicon suppliers was investigated. The use of clean dry air and high throughout wafer batch drying techniques was shown to lower the cost of wafer drying. A two stage texturizing process was examined for suitability in large scale production. Also, an in-depth gettering study with the two stage texturizing process was performed for the enhancement of solar cell efficiency, minimization of current versus voltage curve dispersion, and improvement in process reproducibility. The 10% efficiency improvement goal was exceeded for the near term implementation of flat plate photovoltaic cost reduction
A Postscript on the Japanese-American \u27Immigration\u27 Dispute, 1868-1924: A Diplomatic Tinderbox
On asymptotic normality for m
Let (Xn) be a sequence of m-dependent random variables, not necessarily equally distributed. We give a Berry-Esseen estimate of the convergence to normality of a suitable normalization of a U-statistic of the (Xn). This bound holds under moment assumptions quite weaker than the existence of third moments for the kernel. Since we obtain the sharpest bound, the order of the bound can not be improved
Radio Spectra and NVSS Maps of Decametric Sources
We constructed radio spectra for ~1400 UTR-2 sources and find that 46% of
them have concave curvature. Inspection of NVSS maps of 700 UTR sources
suggests that half of all UTR sources are either blends of two or more sources
or have an ultra-steep spectrum (USS). The fraction of compact USS sources in
UTR may be near 10%. Using NVSS and the Digitized Sky Survey(s) we expect to
double the UTR optical identification rate from currently ~19%.Comment: 2 pages, no figures; to appear in Proc. "Observational Cosmology with
the New Radio Surveys", eds. M. Bremer, N. Jackson & I. Perez-Fournon, Kluwer
Acad. Pres
Quasi-dark Mode in a Metamaterial for Analogous Electromagnetically-induced Transparency
We study a planar metamaterial supporting electromagnetically-induced
transparency (EIT)-like effect by exploiting the coupling between bright and
quasi-dark eigenmodes. The specific design of such a metamaterial consists of a
cut-wire (CW) and a single-gap split-ring resonator (SRR). From the numerical
and the analytical results we demonstrate that the response of SRR, which is
weakly excited by external electric field, is mitigated to be a quasi-dark
eigenmode in the presence of strongly radiative CW. This result suggests more
relaxed conditions for the realization of devices utilizing the EIT-like
effects in metamaterial, and thereby widens the possibilities for many
different structural implementations.Comment: 11 pages, 4 figure
A glimpse into the future of genome-enabled plant biology from the shores of Cold Spring Harbor
A report on the 10(th) plant genome meeting entitled ‘Plant genomes and biotechnology: from genes to networks’, held at Cold Spring Harbor Laboratory, 2–5 December, 2015
Rotation of the cluster of galaxies A2107
We present indications of rotation in the galaxy cluster A2107 by a method
that searches for the maximum gradient in the velocity field in a flat
disk-like model of a cluster. Galaxies from cumulative sub-samples containing
more and more distant members from the cluster centre, are projected onto an
axis passing through the centre and we apply a linear regression model on the
projected distances and the line-of-sight velocities . The axis with the
maximum linear correlation coefficient defines the
direction of the maximum velocity gradient, and consequently it presents the
major axis of the apparently elliptical cluster. Because the effects of
rotation are subtle, we put strong emphasis on the estimation of the
uncertainties of the results by implementing different bootstrap techniques. We
have found the rotational effects are more strongly expressed from distances
Mpc from the cluster centre. The total virial mass of the
cluster is (3.2\pm0.6)\times10^{14} {\cal M}_{\sun}, while the virial mass,
corrected for the rotation, is (2.8\pm0.5) \times 10^{14}{\cal M}_{\sun}.Comment: 7 pages, 9 figures gzipped tar file. to be published in MNRA
Array automated assembly task, phase 2. Low cost silicon solar array project
Several modifications instituted in the wafer surface preparation process served to significantly reduce the process cost to 1.55 cents per peak watt in 1975 cents. Performance verification tests of a laser scanning system showed a limited capability to detect hidden cracks or defects, but with potential equipment modifications this cost effective system could be rendered suitable for applications. Installation of electroless nickel plating system was completed along with an optimization of the wafer plating process. The solder coating and flux removal process verification test was completed. An optimum temperature range of 500-550 C was found to produce uniform solder coating with the restriction that a modified dipping procedure is utilized. Finally, the construction of the spray-on dopant equipment was completed
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