271 research outputs found
Energy-Delay Tradeoffs of Virtual Base Stations With a Computational-Resource-Aware Energy Consumption Model
The next generation (5G) cellular network faces the challenges of efficiency,
flexibility, and sustainability to support data traffic in the mobile Internet
era. To tackle these challenges, cloud-based cellular architectures have been
proposed where virtual base stations (VBSs) play a key role. VBSs bring further
energy savings but also demands a new energy consumption model as well as the
optimization of computational resources. This paper studies the energy-delay
tradeoffs of VBSs with delay tolerant traffic. We propose a
computational-resource-aware energy consumption model to capture the total
energy consumption of a VBS and reflect the dynamic allocation of computational
resources including the number of CPU cores and the CPU speed. Based on the
model, we analyze the energy-delay tradeoffs of a VBS considering BS sleeping
and state switching cost to minimize the weighted sum of power consumption and
average delay. We derive the explicit form of the optimal data transmission
rate and find the condition under which the energy optimal rate exists and is
unique. Opportunities to reduce the average delay and achieve energy savings
simultaneously are observed. We further propose an efficient algorithm to
jointly optimize the data rate and the number of CPU cores. Numerical results
validate our theoretical analyses and under a typical simulation setting we
find more than 60% energy savings can be achieved by VBSs compared with
conventional base stations under the EARTH model, which demonstrates the great
potential of VBSs in 5G cellular systems.Comment: 5 pages, 3 figures, accepted by ICCS'1
Integrated photonics modular arithmetic processor
Integrated photonics computing has emerged as a promising approach to
overcome the limitations of electronic processors in the post-Moore era,
capitalizing on the superiority of photonic systems. However, present
integrated photonics computing systems face challenges in achieving
high-precision calculations, consequently limiting their potential
applications, and their heavy reliance on analog-to-digital (AD) and
digital-to-analog (DA) conversion interfaces undermines their performance. Here
we propose an innovative photonic computing architecture featuring scalable
calculation precision and a novel photonic conversion interface. By leveraging
Residue Number System (RNS) theory, the high-precision calculation is
decomposed into multiple low-precision modular arithmetic operations executed
through optical phase manipulation. Those operations directly interact with the
digital system via our proposed optical digital-to-phase converter (ODPC) and
phase-to-digital converter (OPDC). Through experimental demonstrations, we
showcase a calculation precision of 9 bits and verify the feasibility of the
ODPC/OPDC photonic interface. This approach paves the path towards liberating
photonic computing from the constraints imposed by limited precision and AD/DA
converters.Comment: 23 pages, 9 figure
Online near-infrared analysis coupled with MWPLS and SiPLS models for the multi-ingredient and multi-phase extraction of licorice (Gancao)
Additional file 1. Table S1. The sampling intervals in different extraction phases. Table S2. The HPLC results of different indicators. Table S3. The evaluation parameters of PLS and SiPLS models
Chromogenic and fluorogenic detection of a nerve agent simulant with a rhodamine-deoxylactam based sensor
A chromogenic and fluorogenic detection of a nerve agent simulant was developed based on diethyl chlorophosphate triggered tandem phosphorylation and intramolecular cyclization of N-(rhodamine B)-deoxylactam-2-aminoethanol.NSF China[20802060, 21072162]; Natural Science Foundation of Fujian Province of China[2011J06004]; Fundamental Research Funds for the Central Universities[2011121020
Determination of erlotinib in rabbit plasma by liquid chromatography mass spectrometry
A sensitive and selective liquid chromatography mass spectrometry (LC–MS) method for determination of erlotinib in rabbit plasma was developed. After addition of midazolam as internal standard (IS), protein precipitation by acetonitrile was used as sample preparation. Chromatographic separation was achieved on a Zorbax SB-C18 (2.1 × 150 mm, 5 μm) column with acetonitrile-0.1 % formic acid as mobile phase with gradient elution. Electrospray ionization (ESI) source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used to quantification using target fragment ions m/z 394→336 for erlotinib and m/z 326→291 for the IS. Calibration plots were linear over the range of 5-2000 ng/mL for erlotinib in plasma. Lower limit of quantification (LLOQ) for erlotinib was 5 ng/mL. Mean recovery of erlotinib from plasma was in the range 84.5-95.7 %. CV of intra-day and interday precision were both less than 12 %. This method is simple and sensitive enough to be used in pharmacokinetic research for determination of erlotinib in rabbit plasma.Colegio de Farmacéuticos de la Provincia de Buenos Aire
Determination of erlotinib in rabbit plasma by liquid chromatography mass spectrometry
A sensitive and selective liquid chromatography mass spectrometry (LC–MS) method for determination of erlotinib in rabbit plasma was developed. After addition of midazolam as internal standard (IS), protein precipitation by acetonitrile was used as sample preparation. Chromatographic separation was achieved on a Zorbax SB-C18 (2.1 × 150 mm, 5 μm) column with acetonitrile-0.1 % formic acid as mobile phase with gradient elution. Electrospray ionization (ESI) source was applied and operated in positive ion mode; multiple reaction monitoring (MRM) mode was used to quantification using target fragment ions m/z 394→336 for erlotinib and m/z 326→291 for the IS. Calibration plots were linear over the range of 5-2000 ng/mL for erlotinib in plasma. Lower limit of quantification (LLOQ) for erlotinib was 5 ng/mL. Mean recovery of erlotinib from plasma was in the range 84.5-95.7 %. CV of intra-day and interday precision were both less than 12 %. This method is simple and sensitive enough to be used in pharmacokinetic research for determination of erlotinib in rabbit plasma.Colegio de Farmacéuticos de la Provincia de Buenos Aire
A 550,000-year record of East Asian monsoon rainfall from Be-10 in loess
Cosmogenic Be-10 flux from the atmosphere is a proxy for rainfall. Using this proxy, we derived a 550,000-year-long record of East Asian summer monsoon (EASM) rainfall from Chinese loess. This record is forced at orbital precession frequencies, with higher rainfall observed during Northern Hemisphere summer insolation maxima, although this response is damped during cold interstadials. The Be-10 monsoon rainfall proxy is also highly correlated with global ice-volume variations, which differs from Chinese cave delta O-18, which is only weakly correlated. We argue that both EASM intensity and Chinese cave delta O-18 are not governed by high-northern-latitude insolation, as suggested by others, but rather by low-latitude interhemispheric insolation gradients, which may also strongly influence global ice volume via monsoon dynamics
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