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A Framework for 3D Pushbroom Imaging
Pushbroom cameras produce one-dimensional images of a scene with high resolution at a high frame-rate. As a result, they provide superior data compared to conventional two-dimensional cameras in cases where the scene of interest can be temporally scanned. In this paper, we consider the problem of recovering the structure of a scene using a set of pushbroom cameras. Although pushbroom cameras have been used to recover scene structure in the past, the algorithms for recovery were developed separately for different camera motions such as translation and rotation. In this paper, we present a general framework of structure recovery for pushbroom cameras with 6 degree-of-freedom motion. We analyze the translation and rotation cases using our framework and demonstrate that several previous results are really special cases of our result. Using this framework, we also show that three or more pushbroom cameras can be used to compute scene structure as well as motion of translation or rotation. We conclude with a set of experiments that demonstrate the use of pushbroom imaging to recover structure from unknown motion
Correct Effective Potential of Supersymmetric Yang-Mills Theory on M^4\times S^1
We study an supersymmetric Yang-Mills theory defined on
. The vacuum expectation values for adjoint scalar field in
vector multiplet, though important, has been overlooked in evaluating one-loop
effective potential of the theory. We correctly take the vacuum expectation
values into account in addition to the Wilson line phases to give an expression
for the effective potential, and gauge symmetry breaking is discussed. In
evaluating the potential, we employ the Scherk-Schwarz mechanism and introduce
bare mass for gaugino in order to break supersymmetry. We also obtain masses
for the scalars, the adjoint scalar, and the component gauge field for the
direction in case of the SU(2) gauge group. We observe that large
supersymmetry breaking gives larger mass for the scalar. This analysis is
easily applied to the case.Comment: 12 pages, 1 figur
Discovery of H alpha absorption in the unusual broad absorption line quasar SDSS J083942.11+380526.3
We discovered an H alpha absorption in a broad H alpha emission line of an
unusual broad absorption line quasar, SDSS J083942.11+380526.3 at z=2.318, by
near-infrared spectroscopy with the Cooled Infrared Spectrograph and Camera for
OHS (CISCO) on the Subaru telescope. The Presence of non-stellar H alpha
absorption is known only in the Seyfert galaxy NGC 4151 to date, thus our
discovery is the first case for quasars. The H alpha absorption line is
blueshifted by 520 km/s relative to the H alpha emission line, and its redshift
almost coincides with those of UV low-ionization metal absorption lines. The
width of the H alpha absorption (~ 340 km/s) is similar to those of the UV
low-ionization absorption lines. These facts suggest that the H alpha and the
low-ionization metal absorption lines are produced by the same low-ionization
gas which has a substantial amount of neutral gas. The column density of the
neutral hydrogen is estimated to be ~ 10^18 cm^-2 by assuming a gas temperature
of 10,000 K from the analysis of the curve of growth. The continuum spectrum is
reproduced by a reddened (E(B-V) ~ 0.15 mag for the SMC-like reddening law)
composite quasar spectrum. Furthermore, the UV spectrum of SDSS
J083942.11+380526.3 shows a remarkable similarity to that of NGC 4151 in its
low state, suggesting the physical condition of the absorber in SDSS
J083942.11+380526.3 is similar to that of NGC 4151 in the low state. As
proposed for NGC 4151, SDSS J083942.11+380526.3 may be also seen through the
close direction of the surface of the obscuring torus.Comment: Accepted for publication in Ap
Grand Unification of Flavor Mixings
An origin of flavor mixings in quark and lepton sectors is still a mystery,
and a structure of the flavor mixings in lepton sector seems completely
different from that of quark sector. In this letter, we point out that the
flavor mixing angles in quark and lepton sectors could be unified at a high
energy scale, when neutrinos are degenerate. It means that a minimal flavor
violation at a high energy scale can induce a rich variety of flavor mixings in
quark and lepton sectors at a low energy scale through quantum corrections.Comment: 5 pages, 12 figures, references added, version to appear in EP
Effective theoretical approach of Gauge-Higgs unification model and its phenomenological applications
We derive the low energy effective theory of Gauge-Higgs unification (GHU)
models in the usual four dimensional framework. We find that the theories are
described by only the zero-modes with a particular renormalization condition in
which essential informations about GHU models are included. We call this
condition ``Gauge-Higgs condition'' in this letter. In other wards, we can
describe the low energy theory as the SM with this condition if GHU is a model
as the UV completion of the Standard Model. This approach will be a powerful
tool to construct realistic models for GHU and to investigate their low energy
phenomena.Comment: 18 pages, 2 figures; Two paragraphs discussing the applicable scope
of this approach are adde
Anarchy and Hierarchy
We advocate a new approach to study models of fermion masses and mixings,
namely anarchy proposed in hep-ph/9911341. In this approach, we scan the O(1)
coefficients randomly. We argue that this is the correct approach when the
fundamental theory is sufficiently complicated. Assuming there is no physical
distinction among three generations of neutrinos, the probability distributions
in MNS mixing angles can be predicted independent of the choice of the measure.
This is because the mixing angles are distributed according to the Haar measure
of the Lie groups whose elements diagonalize the mass matrices. The
near-maximal mixings, as observed in the atmospheric neutrino data and as
required in the LMA solution to the solar neutrino problem, are highly
probable. A small hierarchy between the Delta m^2 for the atmospheric and the
solar neutrinos is obtained very easily; the complex seesaw case gives a
hierarchy of a factor of 20 as the most probable one, even though this
conclusion is more measure-dependent. U_{e3} has to be just below the current
limit from the CHOOZ experiment. The CP-violating parameter sin delta is
preferred to be maximal. We present a simple SU(5)-like extension of anarchy to
the charged-lepton and quark sectors which works well phenomenologically.Comment: 26 page
Field-induced metal-insulator transition and switching phenomenon in correlated insulators
We study the nonequilibrium switching phenomenon associated with the
metal-insulator transition under electric field E in correlated insulator by a
gauge-covariant Keldysh formalism. Due to the feedback effect of the resistive
current I, this occurs as a first-order transition with a hysteresis of I-V
characteristics having a lower threshold electric field (\sim 10^4 Vcm^{-1})
much weaker than that for the Zener breakdown. It is also found that the
localized mid-gap states introduced by impurities and defects act as hot spots
across which the resonant tunneling occurs selectively, which leads to the
conductive filamentary paths and reduces the energy cost of the switching
function.Comment: 5 pages, 3 figures. A study on the metal-insulator transition in
correlated insulators was adde
Lack of the Sodium-Driven Chloride Bicarbonate Exchanger NCBE Impairs Visual Function in the Mouse Retina
Regulation of ion and pH homeostasis is essential for normal neuronal function. The sodium-driven chloride bicarbonate exchanger NCBE (Slc4a10), a member of the SLC4 family of bicarbonate transporters, uses the transmembrane gradient of sodium to drive cellular net uptake of bicarbonate and to extrude chloride, thereby modulating both intracellular pH (pHi) and chloride concentration ([Cl-]i) in neurons. Here we show that NCBE is strongly expressed in the retina. As GABAA receptors conduct both chloride and bicarbonate, we hypothesized that NCBE may be relevant for GABAergic transmission in the retina. Importantly, we found a differential expression of NCBE in bipolar cells: whereas NCBE was expressed on ON and OFF bipolar cell axon terminals, it only localized to dendrites of OFF bipolar cells. On these compartments, NCBE colocalized with the main neuronal chloride extruder KCC2, which renders GABA hyperpolarizing. NCBE was also expressed in starburst amacrine cells, but was absent from neurons known to depolarize in response to GABA, like horizontal cells. Mice lacking NCBE showed decreased visual acuity and contrast sensitivity in behavioral experiments and smaller b-wave amplitudes and longer latencies in electroretinograms. Ganglion cells from NCBE-deficient mice also showed altered temporal response properties. In summary, our data suggest that NCBE may serve to maintain intracellular chloride and bicarbonate concentration in retinal neurons. Consequently, lack of NCBE in the retina may result in changes in pHi regulation and chloride-dependent inhibition, leading to altered signal transmission and impaired visual function
Damage mechanisms of pathogenic bacteria in drinking water during chlorine and solar disinfection
This study aimed at elucidating the inactivation mechanisms of pathogenic bacteria in drinking water during chlorine and solar disinfection using a simple plating method. The well-known bacterial model Escherichia coli was used as pathogenic bacteria for the experiments. The damage mechanisms of E. coli were evaluated by simple plating method on selective, less selective and non-selective media. Results showed that, injured E. coli were detected at different levels during chlorine and solar disinfection. The use of selective media during water quality control showed effectively the destruction of E. coli during solar disinfection while the removal of E. coli during chlorine disinfection was not ensured. The damage of cell components and/or metabolic functions showed that there is a primary and mainly damage of E. coli during chorine and solar disinfection. Chlorination firstly and mainly damaged membrane cell followed by that of enzymatic functions and nucleic acid; while solar disinfection damaged mainly nucleic acid. The use of simple plating method in water quality control is limited by the choice of plating media depending on the disinfectant used. The understanding of the damage mechanisms of pathogenic bacteria cells during disinfection helps improve drinking water quality control and develops more effective disinfection strategies.© 2016 International Formulae Group. All rights reserved.Keywords: Drinking water, pathogenic bacteria, E. coli, damage mechanisms, chlorine disinfection, solar disinfectio
New contribution to dimension five operators on proton decay in anomaly mediation scenario
In supergravity, effective superpotential relevant to dimension five
operators on proton decay processes also leads to supersymmetry breaking terms
among sfermions, dimension four operators. These dimension four operators
induce the dimension five operators through 1-loop diagrams dressed by
gauginos. We find that, in a class of models with the anomaly mediation, the
1-loop contributions can be comparable to those at the tree level. Therefore,
such operators have a great impact on proton decay rate. Depending on a
universal phase of gaugino masses and soft mass spectrum, the proton decay rate
can be enhanced or suppressed.Comment: 8 pages, no figure. A few minor changes have been mad
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