20,447 research outputs found
Simplified Algorithm for Dynamic Demand Response in Smart Homes Under Smart Grid Environment
Under Smart Grid environment, the consumers may respond to incentive--based
smart energy tariffs for a particular consumption pattern. Demand Response (DR)
is a portfolio of signaling schemes from the utility to the consumers for load
shifting/shedding with a given deadline. The signaling schemes include
Time--of--Use (ToU) pricing, Maximum Demand Limit (MDL) signals etc. This paper
proposes a DR algorithm which schedules the operation of home appliances/loads
through a minimization problem. The category of loads and their operational
timings in a day have been considered as the operational parameters of the
system. These operational parameters determine the dynamic priority of a load,
which is an intermediate step of this algorithm. The ToU pricing, MDL signals,
and the dynamic priority of loads are the constraints in this formulated
minimization problem, which yields an optimal schedule of operation for each
participating load within the consumer provided duration. The objective is to
flatten the daily load curve of a smart home by distributing the operation of
its appliances in possible low--price intervals without violating the MDL
constraint. This proposed algorithm is simulated in MATLAB environment against
various test cases. The obtained results are plotted to depict significant
monetary savings and flattened load curves.Comment: This paper was accepted and presented in 2019 IEEE PES GTD Grand
International Conference and Exposition Asia (GTD Asia). Furthermore, the
conference proceedings has been published in IEEE Xplor
Magnon diffusion lengths in bulk and thin film Fe3O4 for spin Seebeck applications
The magnon diffusion length (MDL) is understood to play a major role in the thickness dependence of spin Seebeck effect (SSE) voltages in Fe3O4/Pt thin films. Here we extract the MDL in an Fe3O4 single crystal using inelastic neutron scattering (INS) and in Fe3O4/Pt thin films using accurate heat flux SSE and static magnetization measurements. The INS MDLs were 34 ± 8 nm at 300 K and 27 ± 6 nm at 50 K. The SSE MDLs decreased with temperature (19 ± 2 nm at 300 K and 13 ± 4 nm at 50 K), but were markedly smaller. Whilst the bulk MDL is expected to be an upper limit of the MDL in thin films, we show that the film magnetization must be considered to obtain MDLs from SSE measurements. This study highlights the importance of disentangling the role of various effects in SSE measurements which is crucial in increasing the efficiencies of thermomagnetic energy harvesting devices
Validasi Modifikasi Metode Volumetrik Penentuan Konsentrasi Sn (Timah) Pada Konsentrat Timah
The analysis techniques for determining the concentration of Stanum (Sn) in Tin Concentrate has been developing since the 19th century. Various methods and analysis techniques are to find the most effective and efficient method enabling to achieve optimal results. In this study, a modification of the classic volumetric method that has been used includes modifications to the use of materials and tools in the analysis. In this study, validation and verification of the modified method was also carried out by determining the value of the parameters of Precision, Accuracy, Method of Detection Limit (MDL) and the Ruggedness and Robustness of the method and comparing the acceptability value based on the existing provisions. on the EURACHEM guide. After performing 25 tests using the NCS DC 35002 Certified Reference Material, it was revealed the value of the parameters for the Precision/Relative Standard Deviation (RSD) to be 0.21% (<0.5 CV Horwitz), the accuracy value is 99.9% with bias 0.06%, the MDL values for Minimum Detection Limit (MDL) and Limit of Quantification (LOQ) are 0.4% and 1.32%, respectively. The value of the ruggedness and robustness of the method was carried out by testing at different times and by different analysts and obtained RSD 0.22% (<2/3 CV Horwitz). From the values of the parameters obtained, it can be concluded that the modification of this method fulfills the acceptance value required by EURACHEM
Application of Gas Chromatography to Determination of Total Organic Fluorine after Defluorination of Perfluorooctanoic Acid as a Model Compound
Because of the global presence of anthropogenic perfluorinated organic compounds in the environment,
foods and living organisms, and their large structural variety, it can be helpful to develop a method
for determination of their total content at trace level in different matrices. In the developed method,
the defluorination was carried with sodium biphenyl, derivatization of released fluoride to triphenylfluorosilane
and determination by gas chromatography. Three detection methods were compared: flameionization
detection, electron capture detection and mass spectrometry. Among them the MS detection
was found to be the most favorable one in terms of the instrumental limit of detection (LOD) , whereas the
flame-ionization detection was considered to be the most favorable in terms of the method limit of detection
(MDL). For the initial sample volume of 1 L and performing the whole procedure of determination,
including preconcentration, the MDL value for perfluorooctanoic acid was evaluated as 0.043 ppb. (doi: 10.5562/cca1798
Mode-Dependent Loss and Gain: Statistics and Effect on Mode-Division Multiplexing
In multimode fiber transmission systems, mode-dependent loss and gain
(collectively referred to as MDL) pose fundamental performance limitations. In
the regime of strong mode coupling, the statistics of MDL (expressed in
decibels or log power gain units) can be described by the eigenvalue
distribution of zero-trace Gaussian unitary ensemble in the small-MDL region
that is expected to be of interest for practical long-haul transmission.
Information-theoretic channel capacities of mode-division-multiplexed systems
in the presence of MDL are studied, including average and outage capacities,
with and without channel state information.Comment: 22 pages, 8 figure
On-line, Single Point Standardization Analysis for Measuring Hydrogen Production by Transition Metal Catalyst in Light Driven Synthesis
An automated SPS-GC-TCD has been optimized to determine hydrogen production in light driven synthesis reactions while operating in real time and being capable of multiple analysis per hour. The SPS-GC-TCD method incorporates two sample loops on a valve, one for a check standard and the other for the sample, eliminating many sources of error associated with gas sampling and allowing for automated calibration during each analytical run. Gas samples containing hydrogen in a percent volume concentration were analyzed and method detection limit (MDL), accuracy and precision measurments have been conducted. Using single point standardization, proof of concept results for the analyzer gave an MDL of 0.73% (v/v%), accuracy of 100%, and precision of 3.7% for hydrogen. These values were comparable to results obtained by a much more intensive 5-point external calibration. The automated system gave extreme improvements in reproducibility, and a detection limit of 0.25% and precision of 1.7%
Water Quality Reporting Limits, Method Detection Limits, and Censored Values: What Does It All Mean?
The Arkansas Water Resources Center (AWRC) maintains a fee-based water-quality lab that is certified by the Arkansas Department of Environmental Quality (ADEQ). The AWRC Water Quality Lab analyzes water samples for a variety of constituents, using standard methods for the analysis of water samples (APHA 2012). The lab generates a report on the analysis, which is provided to clientele, and reports the concentrations or values as measured. Often times the concentrations or values might be very small, even zero as reported by the lab – what does this mean? How should we use this information? This document is intended to help our clientele understand the analytical report, the values, and how one might interpret information near the lower analytical limits. Every client wants the analysis of their water sample(s) to be accurate and precise, but what do we really mean when we say those two words? These words are often used synonymously or thought of as being the same, but the two words mean two different things. Both are equally important when analyzing water samples for constituent concentrations
Exact Model for Mode-Dependent Gains and Losses in Multimode Fiber
In the strong mode coupling regime, the model for mode-dependent gains and
losses (collectively referred as MDL) of a multimode fiber is extended to the
region with large MDL. The MDL is found to have the same statistical properties
as the eigenvalues of the summation of two matrices. The first matrix is a
random Gaussian matrix with standard deviation proportional to the accumulated
MDL. The other matrix is a deterministic matrix with uniform eigenvalues
proportional to the square of the accumulated MDL. The results are analytically
correct for fibers with two or large number of modes, and also numerically
verified for other cases.Comment: 7 pages, 2 figures, 2 table
Discrete MDL Predicts in Total Variation
The Minimum Description Length (MDL) principle selects the model that has the
shortest code for data plus model. We show that for a countable class of
models, MDL predictions are close to the true distribution in a strong sense.
The result is completely general. No independence, ergodicity, stationarity,
identifiability, or other assumption on the model class need to be made. More
formally, we show that for any countable class of models, the distributions
selected by MDL (or MAP) asymptotically predict (merge with) the true measure
in the class in total variation distance. Implications for non-i.i.d. domains
like time-series forecasting, discriminative learning, and reinforcement
learning are discussed.Comment: 15 LaTeX page
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