نتایج جستجو برای: conical and normal conical forms

تعداد نتایج: 16882824  

2003
Steffen Metzger

When M-theory is compactified on G2-holonomy manifolds with conical singularities, charged chiral fermions are present and the low-energy fourdimensional theory is potentially anomalous. We reconsider the issue of anomaly cancellation, first studied by Witten. We propose a mechanism that provides local cancellation of all gauge and mixed gauge-gravitational anomalies, i.e. separately for each c...

1999
PAO K. WANG

Mathematical expressions based on earlier ideas of the author are given to describe the three-dimensional surfaces of hexagonal ice crystals and conical graupel and hail particles. In the former class, the expressions closely parallel the expression for prolate spheroid but the cross section is transformed into a hexagon by an expression designed previously. A special transformation containing ...

The output of a piezoelectric nanogenerator based on ZnO nanowire is largely affected by the shape of nanowire. In order to obtain mechanically stable nanogenerator with high performance, the investigation of mechanical and electrical characteristics related to the nanowires and materials used in nanogenerators are of great interest and significance. This paper presents the various behavior of ...

2010
T. Matsuoka

The generation of energetic electron and proton beams was studied from the interaction of high intensity laser pulses with pre-drilled conical targets. These conical targets are laser machined onto flat targets using 7–180μJ pulses whose axis of propagation is identical to that of the main high intensity pulse. This method significantly relaxes requirements for alignment of conical targets in s...

1992
Richard M. Wood Steven X. S. Bauer

A wing-design study has been conducted on a 65 swept leading-edge delta wing in which the wing geometry was modi ed to take advantage of the naturally occurring ow that forms over a slender wing in a supersonic ow eld. Three-dimensional nonlinear analysis methods were used in the study which was divided into three parts|preliminary design, initial design, and nal design. In the preliminary desi...

2008
Paolo d’Alessandro

In this paper we develop extensions of the conical techniques exposed in the book [3], and we develop new algorithms as well. We make an effort to keep this paper enough self-contained, however, the book [3] (hereafter often referred to as ”the book” for the sake of brevity) can be useful for further details. Such book is an outgrow of two papers published on the journal Optimization, namely [1...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2009
Tanja Bosak Biqing Liang Min Sub Sim Alexander P Petroff

Conical stromatolites are thought to be robust indicators of the presence of photosynthetic and phototactic microbes in aquatic environments as early as 3.5 billion years ago. However, phototaxis alone cannot explain the ubiquity of disrupted, curled, and contorted laminae in the crests of many Mesoproterozoic, Paleoproterozoic, and some Archean conical stromatolites. Here, we demonstrate that ...

2016
S. R. Greig A. Y. Elezzabi

We present a method for the generation of high kinetic energy attosecond electron packets via magnetostatic and aperture filtering of conical surface plasmon (SP) accelerated electrons. The conical SP waves are excited by coupling an ultrafast radially polarized laser beam to a conical silica lens coated with an Ag film. Electromagnetic and particle tracking models are employed to characterize ...

2012
George S. Kliros

The need of ultrawideband (UWB) antennas with omni-directional coverage is increasing for both military and commercial applications (Wiesbeck et. al., 2009; Minin, 2010). The UWB radio technology promises high resolution radar applications, sensor networks with a large number of sensors for industrial or home surveillance as well as high data-rate communication over short range for personal are...

The geometry of a collector is one of the important factors that can increase the incident radiation on the collector surface. In the present study, the incident radiation for a stationary collector with cone geometry, i.e. a conical collector, is theoretically and experimentally investigated. This type of collector is always stable and does not need a fixture to install. Moreover, it has a...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید