A multivariate statistical clustering technique—based on the iterative k-means algorithm of Hartigan (Hartigan 1975)—has been used to extract patterns of climatological significance from 200 years of general circulation model (GCM) output. Originally developed and implemented on a Beowulf-style parallel computer constructed by Hoffman and Hargrove from surplus commodity desktop PCs (Hargrove et...

introduction: poor sensitivity and poor signal to noise ratio because of low injected thallium dose and presence of scattered photons are the main problems in using thallium in scintigraphic imaging of the heart. scattered photons are the main cause of degrading the contrast and resolution in spect imaging that result in error in quantification. thallium decay is very complicated and photons ar...

Optical pump-probe setups are commonly used for excitation and investigation of the spin dynamics in various types magnetic materials. Usually spatially homogeneous is considered, but here authors describe optical $n\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}u\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}f\phantom{\rule{0}{0ex}}o\phantom{\rul...

An eigenvalue of a graph G is called main eigenvalue if it has an eigenvector the sum of whose entries is not equal to zero. Hoffman [A.J. Hoffman, On the polynomial of a graph, Amer. Math. Monthly 70 (1963) 30–36] proved that G is a connected k-regular graph if and only if n ∏t i=2(A− λiI ) = ∏t i=2(k − λi) · J , where I is the unit matrix and J the all-one matrix and λ1 = k, λ2, . . . , λt ar...

introduction: in this study, we intend to use diffuse optical tomography (dot) as a noninvasive, safe and low cost technique that can be considered as a functional imaging method and mention the importance of image reconstruction in accuracy and procession of image. one of the most important and fastest methods in image reconstruction is the boundary element method (bem). this method is introdu...

Andrew J. Hoffman, Professor of Sustainable Enterprise at the University Michigan, has written “The Engaged Scholar — Expanding Impact Academic Research in Today's World” (2021 Stanford Press). According to author, most researchers want make a difference, but academic institutions often do not value public engagement, leading disengaged scientists. Hoffman gives and reexamines arguments for why...

Neurons exhibit $e\phantom{\rule{0}{0ex}}x\phantom{\rule{0}{0ex}}c\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}b\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}l\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}y$, the dynamical property that is likewise key to biologically inspired artificial intelligence. The neuromorphic c...

BACKGROUND Several techniques for fixation of the posterior chamber intraocular lens (IOL) have been developed. We evaluate long-term functional outcomes and safety of posterior chamber IOL implantation using Hoffman scleral haptic fixation and sutureless Sharioth technique in patients with posttraumatic and postoperative aphakia. METHODS This retrospective case-series included 42 eyes operat...

It has been a long-standing problem in $N$-electron systems as to how solve the Dyson equation with quasiparticle wave functions defined $\ensuremath{\langle}\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Psi}}}_{0}^{N}\phantom{\rule{0.16em}{0ex}}|\phantom{\rule{0.16em}{0ex}}{\ensuremath{\psi}}_{s}(\mathbit{r})\phantom{\rule{0.16em}{0ex}}|\phantom{\rule{0.16em}{0ex}}{\mathrm{\ensuremath{\Psi...