246 research outputs found
Study of a zirconium getter for purification of xenon gas
Oxygen, nitrogen and methane purification efficiencies for a common zirconium
getter are measured in 1050 Torr of xenon gas. Starting with impurity
concentrations near 10^{-6} g/g, the outlet impurity level is found to be less
than 120*10^{-12} g/g for O2 and less than 950*10^{-12} g/g for N2. For methane
we find residual contamination of the purified gas at concentrations varying
over three orders of magnitude, depending on the purifier temperature and the
gas flow rate. A slight reduction in the purifier's methane efficiency is
observed after 13 mg of this impurity has been absorbed, which we attribute to
partial exhaustion of the purifier's capacity for this species. We also find
that the purifier's ability to absorb N2 and methane can be extinguished long
before any decrease in O2 performance is observed, and slower flow rates should
be employed for xenon purification due to the cooling effect that the heavy gas
has on the getter.Comment: 14 pages, 5 figure
Dual-Processor Design of Energy Efficient Fault-Tolerant System
A popular approach to guarantee fault tolerance in
safety-critical applications is to run the application on
two processors. A checkpoint is inserted at the comple-
tion of the primary copy. If there is no fault, the sec-
ondary processor terminates its execution. Otherwise,
should the fault occur, the second processor continues
and completes the application before its deadline. In
this paper, we study the energy efficiency of such dual-
processor system. Specifically, we first derive an opti-
mal static voltage scaling policy for single periodic task.
We then extend it to multiple periodic tasks based on
worst case execution time (WCET) analysis. Finally,
we discuss how to further reduce system’s energy con-
sumption at run time by taking advantage of the actual
execution time which is less than the WCET. Simula-
tion on real-life benchmark applications shows that our
technique can save up to 80% energy while still provid-
ing fault tolerance
How Many Solutions Does a SAT Instance Have?
Our goal is to investigate the solution space of a given Boolean
Satisfiability (SAT) instance. In particular, we are interested in determining
the size of the solution space – the number of truth assignments
that make the SAT instance true – and finding all such
truth assignments, if possible. This apparently hard problem has
both theoretical and practical values. We propose an exact algorithm
based on exhaustive search that Solves the instance Once
and Finds All Solutions (SOFAS) and several sampling techniques
that estimate the size of the solution space. SOFAS works better
for SAT instances of small size with a 5X-100X speed-up over the
brute force search algorithm. The sampling techniques estimate
the solution space reasonably well for standard SAT benchmarks
How Many Solutions Does a SAT Instance Have?
Our goal is to investigate the solution space of a given Boolean
Satisfiability (SAT) instance. In particular, we are interested in determining
the size of the solution space – the number of truth assignments
that make the SAT instance true – and finding all such
truth assignments, if possible. This apparently hard problem has
both theoretical and practical values. We propose an exact algorithm
based on exhaustive search that Solves the instance Once
and Finds All Solutions (SOFAS) and several sampling techniques
that estimate the size of the solution space. SOFAS works better
for SAT instances of small size with a 5X-100X speed-up over the
brute force search algorithm. The sampling techniques estimate
the solution space reasonably well for standard SAT benchmarks
The JEREMI-project on thermocapillary convection in liquid bridges. Part A : Overview of particle accumulation structures
The rapid accumulation of particles suspended in a thermocapillary liquid bridge is planned to be investigated during the JEREMI experiment on the International Space Station scheduled for 2016. An overview is given of the current status of experimental and numerical investigations of this phenomenon
ОЖИРІННЯ ЯК СОЦІАЛЬНА ПРОБЛЕМА СУЧАСНОСТІ
The article analyzes the combined incidence course alimentary obesity.It was established that alimentary obesity in the population of Ternopil region often combined with endocrine disorders, including diabetes mellitus type 2 (in 62.7% of patients) and cardiac pathology, namely hypertension (34.3% patients), while in gender aspect woman more often had comorbidity pathology. The results indicate that alimentary obesity contributes to an unfavorable background for the main course of the disease.У статті проаналізовано захворюваність на поєднаний перебіг аліментарного ожиріння. Встановлено, що аліментарне ожиріння в населення Тернопільської області найчастіше поєднується з ендокринною патологією, зокрема, з цукровим діабетом 2 типу (у 62,7 % хворих) та кардіологічною патологією, а саме з гіпертонічною хворобою (34,3 % пацієнтів), при цьому в гендерному аспекті частіше на поєднані патології хворіють жінки. Отримані результати свідчать про те, що аліментарне ожиріння призводить до формування несприятливого тла для перебігу основної хвороби
A Randomized Study Evaluating Oral Fusidic Acid (CEM-102) in Combination With Oral Rifampin Compared With Standard-of-Care Antibiotics for Treatment of Prosthetic Joint Infections: A Newly Identified Drug–Drug Interaction
BACKGROUND: Fusidic acid (FA) has been used for decades for bone infection, including prosthetic joint infection (PJI), often in combination with rifampin (RIF). An FA/RIF pharmacokinetic interaction has not previously been described.
METHODS: In a phase 2 open-label randomized study, we evaluated oral FA/RIF vs standard-of-care (SOC) intravenous antibiotics for treatment of hip or knee PJI. Outcome assessment occurred at reimplantation (week 12) for subjects with 2-stage exchange, and after 3 or 6 months of treatment for subjects with hip or knee debride and retain strategies, respectively.
RESULTS: Fourteen subjects were randomized 1:1 to FA/RIF or SOC. Pharmacokinetic profiles were obtained for 6 subjects randomized to FA/RIF. FA concentrations were lower than anticipated in all subjects during the first week of therapy, and at weeks 4 and 6, blood levels continued to decline. By week 6, FA exposures were 40%-45% lower than expected.
CONCLUSIONS: The sponsor elected to terminate this study due to a clearly illustrated drug-drug interaction between FA and RIF, which lowered FA levels to a degree that could influence subject outcomes. Optimization of FA exposure if used in combination with RIF should be a topic of future research.
CLINICAL TRIALS REGISTRATION: NCT01756924
The DRIFT Dark Matter Experiments
The current status of the DRIFT (Directional Recoil Identification From
Tracks) experiment at Boulby Mine is presented, including the latest limits on
the WIMP spin-dependent cross-section from 1.5 kg days of running with a
mixture of CS2 and CF4. Planned upgrades to DRIFT IId are detailed, along with
ongoing work towards DRIFT III, which aims to be the world's first 10 m3-scale
directional Dark Matter detector.Comment: Proceedings of the 3rd International conference on Directional
Detection of Dark Matter (CYGNUS 2011), Aussois, France, 8-10 June 201
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