5,096 research outputs found
Polarization Beam Splitter Based on Self-Collimation of a Hybrid Photonic Crystal
A photonic crystal polarization beam splitter based on photonic band gap and self-collimation effects is designed for optical communication wavelengths. The photonic crystal structure consists of a polarization-insensitive self-collimation region and a splitting region. TM- and TE-polarized waves propagate without diffraction in the self-collimation region, whereas they split by 90 degrees in the splitting region. Efficiency of more than 75% for TM- and TE-polarized light is obtained for a polarization beam splitter size of only 17 μm x 17 μm in a wavelength interval of 60 nm including 1.55 μm
Easy Monitored Entangled States
We discuss the generation and monitoring of durable atomic entangled state
via Raman-type process, which can be used in the quantum information
processing.Comment: 9 pages, 2 figures, the previous title "Durable Entanglement in
Atomic Systems" is replaced by new title, accepted to Appl. Phys. Let
Nanopore Sequencing Technology and Tools for Genome Assembly: Computational Analysis of the Current State, Bottlenecks and Future Directions
Nanopore sequencing technology has the potential to render other sequencing
technologies obsolete with its ability to generate long reads and provide
portability. However, high error rates of the technology pose a challenge while
generating accurate genome assemblies. The tools used for nanopore sequence
analysis are of critical importance as they should overcome the high error
rates of the technology. Our goal in this work is to comprehensively analyze
current publicly available tools for nanopore sequence analysis to understand
their advantages, disadvantages, and performance bottlenecks. It is important
to understand where the current tools do not perform well to develop better
tools. To this end, we 1) analyze the multiple steps and the associated tools
in the genome assembly pipeline using nanopore sequence data, and 2) provide
guidelines for determining the appropriate tools for each step. We analyze
various combinations of different tools and expose the tradeoffs between
accuracy, performance, memory usage and scalability. We conclude that our
observations can guide researchers and practitioners in making conscious and
effective choices for each step of the genome assembly pipeline using nanopore
sequence data. Also, with the help of bottlenecks we have found, developers can
improve the current tools or build new ones that are both accurate and fast, in
order to overcome the high error rates of the nanopore sequencing technology.Comment: To appear in Briefings in Bioinformatics (BIB), 201
Partial evaluation of queries for bit-sliced signature files
Cataloged from PDF version of article.Our research extends the bit-sliced signature organization by introducing a partial evaluation approach for queries. The partial evaluation approach minimizes the response time by using a subset of the on-bits of the query signature. A new signature file optimization method, Partially evaluated Bit-Sliced Signature File (P-BSSF), for multi-term query environments using the partial evaluation approach is introduced. The analysis shows that, with 14% increase in space overhead, P-BSSF provides a query processing time improvement of more than 85% for multi-term query environments with respect to the best performance of the bit-sliced signature file (BSSF) method. Under the sequentiality assumption of disk blocks, P-BSSF provides a desirable response time of 1 second for a database size of one million records with a 28% space overhead, Due to partial evaluation, the desirable response time is guaranteed for queries with several terms
Volume 69, Number 12, December 9, 1949
WOS: A1992HQ04700016A transport method is described which reduces greatly the number of calibration standards needed for hydrogen analysis by neutron induced prompt gamma-rays. The counts in the photopeaks from neutron capture in hydrogen for various standard concentrations, the distribution of the source neutron rate entering the thermal group and the reaction rates in the samples are investigated theoretically using 100 energy group cross sections and experimental Cf-252 spectra for a test configuration. Comparison of theoretical results with those measured from the test configuration shows good agreement
Estimating the Benefits of Electric Vehicle Smart Charging at Non-Residential Locations: A Data-Driven Approach
In this paper, we use data collected from over 2000 non-residential electric
vehicle supply equipments (EVSEs) located in Northern California for the year
of 2013 to estimate the potential benefits of smart electric vehicle (EV)
charging. We develop a smart charging framework to identify the benefits of
non-residential EV charging to the load aggregators and the distribution grid.
Using this extensive dataset, we aim to improve upon past studies focusing on
the benefits of smart EV charging by relaxing the assumptions made in these
studies regarding: (i) driving patterns, driver behavior and driver types; (ii)
the scalability of a limited number of simulated vehicles to represent
different load aggregation points in the power system with different customer
characteristics; and (iii) the charging profile of EVs. First, we study the
benefits of EV aggregations behind-the-meter, where a time-of-use pricing
schema is used to understand the benefits to the owner when EV aggregations
shift load from high cost periods to lower cost periods. For the year of 2013,
we show a reduction of up to 24.8% in the monthly bill is possible. Then,
following a similar aggregation strategy, we show that EV aggregations decrease
their contribution to the system peak load by approximately 40% when charging
is controlled within arrival and departure times. Our results also show that it
could be expected to shift approximately 0.25kWh (~2.8%) of energy per
non-residential EV charging session from peak periods (12PM-6PM) to off-peak
periods (after 6PM) in Northern California for the year of 2013.Comment: Pre-print, under review at Applied Energ
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