34,920 research outputs found
The Architectural Design Rules of Solar Systems based on the New Perspective
On the basis of the Lunar Laser Ranging Data released by NASA on the Silver
Jubilee Celebration of Man Landing on Moon on 21st July 1969-1994, theoretical
formulation of Earth-Moon tidal interaction was carried out and Planetary
Satellite Dynamics was established. It was found that this mathematical
analysis could as well be applied to Star and Planets system and since every
star could potentially contain an extra-solar system, hence we have a large
ensemble of exoplanets to test our new perspective on the birth and evolution
of solar systems. Till date 403 exoplanets have been discovered in 390
extra-solar systems. I have taken 12 single planet systems, 4 Brown Dwarf -
Star systems and 2 Brown Dwarf pairs. Following architectural design rules are
corroborated through this study of exoplanets. All planets are born at inner
Clarke Orbit what we refer to as inner geo-synchronous orbit in case of
Earth-Moon System. By any perturbative force such as cosmic particles or
radiation pressure, the planet gets tipped long of aG1 or short of aG1. Here
aG1 is inner Clarke Orbit. The exoplanet can either be launched on death spiral
as CLOSE HOT JUPITERS or can be launched on an expanding spiral path as the
planets in our Solar System are. It was also found that if the exo-planet are
significant fraction of the host star then those exo-planets rapidly migrate
from aG1 to aG2 and have very short Time Constant of Evolution as Brown Dwarfs
have. This vindicates our basic premise that planets are always born at inner
Clarke Orbit. This study vindicates the design rules which had been postulated
at 35th COSPAR Scientific Assembly in 2004 at Paris, France, under the title
,New Perspective on the Birth & Evolution of Solar Systems.Comment: This paper has been reported to Earth,Moon and Planets Journal as
MOON-S-09-0007
Building the Evryscope: Hardware Design and Performance
The Evryscope is a telescope array designed to open a new parameter space in
optical astronomy, detecting short timescale events across extremely large sky
areas simultaneously. The system consists of a 780 MPix 22-camera array with an
8150 sq. deg. field of view, 13" per pixel sampling, and the ability to detect
objects down to Mg=16 in each 2 minute dark-sky exposure. The Evryscope,
covering 18,400 sq.deg. with hours of high-cadence exposure time each night, is
designed to find the rare events that require all-sky monitoring, including
transiting exoplanets around exotic stars like white dwarfs and hot subdwarfs,
stellar activity of all types within our galaxy, nearby supernovae, and other
transient events such as gamma ray bursts and gravitational-wave
electromagnetic counterparts. The system averages 5000 images per night with
~300,000 sources per image, and to date has taken over 3.0M images, totaling
250TB of raw data. The resulting light curve database has light curves for 9.3M
targets, averaging 32,600 epochs per target through 2018. This paper summarizes
the hardware and performance of the Evryscope, including the lessons learned
during telescope design, electronics design, a procedure for the precision
polar alignment of mounts for Evryscope-like systems, robotic control and
operations, and safety and performance-optimization systems. We measure the
on-sky performance of the Evryscope, discuss its data-analysis pipelines, and
present some example variable star and eclipsing binary discoveries from the
telescope. We also discuss new discoveries of very rare objects including 2 hot
subdwarf eclipsing binaries with late M-dwarf secondaries (HW Vir systems), 2
white dwarf / hot subdwarf short-period binaries, and 4 hot subdwarf reflection
binaries. We conclude with the status of our transit surveys, M-dwarf flare
survey, and transient detection.Comment: 24 pages, 24 figures, accepted PAS
Large-scale photonic Ising machine by spatial light modulation
Quantum and classical physics can be used for mathematical computations that
are hard to tackle by conventional electronics. Very recently, optical Ising
machines have been demonstrated for computing the minima of spin Hamiltonians,
paving the way to new ultra-fast hardware for machine learning. However, the
proposed systems are either tricky to scale or involve a limited number of
spins. We design and experimentally demonstrate a large-scale optical Ising
machine based on a simple setup with a spatial light modulator. By encoding the
spin variables in a binary phase modulation of the field, we show that light
propagation can be tailored to minimize an Ising Hamiltonian with spin
couplings set by input amplitude modulation and a feedback scheme. We realize
configurations with thousands of spins that settle in the ground state in a
low-temperature ferromagnetic-like phase with all-to-all and tunable pairwise
interactions. Our results open the route to classical and quantum photonic
Ising machines that exploit light spatial degrees of freedom for parallel
processing of a vast number of spins with programmable couplings.Comment: https://journals.aps.org/prl/accepted/7007eYb7N091546c41ad4108828a97d5f92006df
Principles of Neuromorphic Photonics
In an age overrun with information, the ability to process reams of data has
become crucial. The demand for data will continue to grow as smart gadgets
multiply and become increasingly integrated into our daily lives.
Next-generation industries in artificial intelligence services and
high-performance computing are so far supported by microelectronic platforms.
These data-intensive enterprises rely on continual improvements in hardware.
Their prospects are running up against a stark reality: conventional
one-size-fits-all solutions offered by digital electronics can no longer
satisfy this need, as Moore's law (exponential hardware scaling),
interconnection density, and the von Neumann architecture reach their limits.
With its superior speed and reconfigurability, analog photonics can provide
some relief to these problems; however, complex applications of analog
photonics have remained largely unexplored due to the absence of a robust
photonic integration industry. Recently, the landscape for
commercially-manufacturable photonic chips has been changing rapidly and now
promises to achieve economies of scale previously enjoyed solely by
microelectronics.
The scientific community has set out to build bridges between the domains of
photonic device physics and neural networks, giving rise to the field of
\emph{neuromorphic photonics}. This article reviews the recent progress in
integrated neuromorphic photonics. We provide an overview of neuromorphic
computing, discuss the associated technology (microelectronic and photonic)
platforms and compare their metric performance. We discuss photonic neural
network approaches and challenges for integrated neuromorphic photonic
processors while providing an in-depth description of photonic neurons and a
candidate interconnection architecture. We conclude with a future outlook of
neuro-inspired photonic processing.Comment: 28 pages, 19 figure
eROSITA Science Book: Mapping the Structure of the Energetic Universe
eROSITA is the primary instrument on the Russian SRG mission. In the first
four years of scientific operation after its launch, foreseen for 2014, it will
perform a deep survey of the entire X-ray sky. In the soft X-ray band (0.5-2
keV), this will be about 20 times more sensitive than the ROSAT all sky survey,
while in the hard band (2-10 keV) it will provide the first ever true imaging
survey of the sky at those energies. Such a sensitive all-sky survey will
revolutionize our view of the high-energy sky, and calls for major efforts in
synergic, multi-wavelength wide area surveys in order to fully exploit the
scientific potential of the X-ray data. The design-driving science of eROSITA
is the detection of very large samples (~10^5 objects) of galaxy clusters out
to redshifts z>1, in order to study the large scale structure in the Universe,
test and characterize cosmological models including Dark Energy. eROSITA is
also expected to yield a sample of around 3 millions Active Galactic Nuclei,
including both obscured and un-obscured objects, providing a unique view of the
evolution of supermassive black holes within the emerging cosmic structure. The
survey will also provide new insights into a wide range of astrophysical
phenomena, including accreting binaries, active stars and diffuse emission
within the Galaxy, as well as solar system bodies that emit X-rays via the
charge exchange process. Finally, such a deep imaging survey at high spectral
resolution, with its scanning strategy sensitive to a range of variability
timescales from tens of seconds to years, will undoubtedly open up a vast
discovery space for the study of rare, unpredicted, or unpredictable
high-energy astrophysical phenomena. In this living document we present a
comprehensive description of the main scientific goals of the mission, with
strong emphasis on the early survey phases.Comment: 84 Pages, 52 Figures. Published online as MPE document. Edited by S.
Allen. G. Hasinger and K. Nandra. Few minor corrections (typos) and updated
reference
FTAs and Philippine Business: Evidence from Transport, Food, and Electronics Firms
Within East Asia, the outward-oriented Philippine economy is a latecomer to using free trade agreements (FTAs) as a trade policy instrument and has relied heavily on the Association of Southeast Asian Nations (ASEAN) for regional liberalization. While negotiating FTAs has consumed scarce time and other resources, limited attention has been hitherto given to evaluating the impact of FTAs-particularly the 15-year-old ASEAN Free Trade Area (AFTA) agreement-on business activity in the Philippines. Using a survey of 155 manufactured goods exporters from three sectors (transport equipment, processed foods, and electronics), this study deals with three questions: (i) Do firms use AFTA and why?; (ii) What impedes firms from using AFTA and other FTAs?; and (iii) What can be done to improve FTA use at firm level in the future? The study finds that utilization of AFTA is higher than expected from existing studies and is set to double in the future. Econometric analysis suggests that firm age, domestic ownership, awareness of FTAs, and membership in the transport sector increase the probability of using AFTA. Surprisingly, among nonusers, a lack of information is the biggest barrier to FTA use. Other impediments to use include the availability of export processing zone incentive schemes, low most-favored-nation rates (particularly in electronics), delays in origin administration, rent-seeking behavior, and nontariff measures in partner country markets. Interestingly, the majority of firms do not think that multiple rules of origin in overlapping Asian FTAs add significantly to business costs. However, there is room for improvement in the system of AFTA rules of origin (e.g., lower value content and introduction of self-certification mechanisms). The examination of institutional support reveals an excess demand for a range of support services (e.g., information, technology-based, and small or medium enterprise extension services) that will enable firms to use FTAs more effectively in the future. The paper concludes by making the case for better mainstreaming of FTAs into Philippine national trade policy and for improving support services to firms.philippines fta impact; philippines fta business; philippines economy ftas
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