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101.
One considers Hilbert space valued measures on the Borel sets of a compact metric space. A natural numerical valued integral of vector valued continuous functions with respect to vector valued measures is defined. Using this integral, different norms (we called them Monge–Kantorovich norm, modified Monge–Kantorovich norm and Hanin norm) on the space of measures are introduced, generalizing the theory of (weak) convergence for probability measures on metric spaces. These norms introduce new (equivalent) metrics on the initial compact metric space. 相似文献
102.
Illegal deforestation is a worldwide problem which may be alleviated through technological means of deforestation monitoring, e.g. wireless sensor networks capable of identifying chain-saw noise, performing sound source localization (SSL), and alerting the authorities to the location of the illegal deforestation activity. In this paper we evaluate the feasibility of performing SSL on low-power, energy-constrained, microphone-array-equipped sensor nodes (SNs) with the Delay-and-Sum (DS) beam-forming algorithm. Our work is the first application of this technique for chain-saw noise. We evaluate array configurations of 4, 8, and 16 microphones, and a multitude of DS algorithm configurations, utilizing chain-saw recordings from the ESC dataset, which is available online. We implement the DS algorithm as a digital circuit in a Xilinx Spartan-6 FPGA and analyze its energy consumption. Our analysis indicates that accurate chain-saw localization can be achieved with much simpler microphone arrays and DS configurations compared to previous work. Furthermore, adding FPGA-based SSL capability to the SN increases the energy consumption by less than 10%, compared to a baseline SN capable only of chain-saw identification through spectral analysis executed in software on the SN microcontroller. 相似文献
103.
Violeta?I.?UricanuEmail author Dan?Donescu Andrei?G.?Banu Sever?Serban Marilena?Vasilescu Mihaela?Olteanu Manuela?Dudau 《Journal of Sol-Gel Science and Technology》2005,34(1):23-39
The interplay between the chemical structure of the precursors, internal organization in the end materials and dye retention was investigated for composites (ormosils) doped with rhodamine B. Besides formulations with triethoxysilanes (RTES) only, we synthesized as well organic–inorganic hybrids with addition of titanium isopropoxide (TIP) and maleic anhydride (MA). The organic (R) functionality of RTES was changed from methyl (MeTES), to phenyl (PTES) and octyl (OTES). Atomic force microscopy and electron microscopy, coupled with thermogravimetric analysis prove that hydrophobicity increase stimulates the transition of film structure: from well-defined, compact particles (for MeTES), to a mixture of porous particles and non-granular material (for MeTES/PTES), with extreme results observed for octyl-based composites. For this latter, the apparent homogeneity comes from cluster-like organization, where the primary entities are pseudo—granules produced by hydrophobic interactions of oligomeric siloxanes. Controlling the composition and gelation procedure resulted in doped composites with good optical transparency and rhodamine B fluorescence emission bands at around 580 nm. Dye transport inside the inorganic structure is not facilitated when: (a) the particles have a compact (nonporous) inner structure and (b) the recipe does not contain the TIP/MA combination. For silica-based films, the dye is located in the macropores (between the granules) of the material and could be easy removed by washing with acetone. On the contrary, using TIP/MA changes not only the internal composition of the granular-like material (by creating a microporous titania-rich outer-shell of the particles) but also the affinity of the Rh-B to permeate and reside inside these new structures. 相似文献
104.
If Exc is the set of all excessive measures associated with a submarkovian resolvent on a Lusin measurable space and B is a balayage on Exc then we show that for any mExc there exists a basic set A (determined up to a m-polar set) such that B=(BA)* for any Exc, m. The m-quasi-Lindelöf property (for the fine topology) holds iff for any B there exists the smallest basic set A as above. We characterize the case when any B is representable i.e. there exists a basic set such that B=(BA)* on Exc. 相似文献
105.
106.
107.
We first summarize some results recently published by the authors on the application of classical robust servomechanism problem (RSP) to electrohydraulic servos. We present a solution consisting of three compensators: an integrator of the tracking error, a LQR stabilizing compensator and an antiwindup compensator. In this work we extend the analysis of the proposed solution by investigating the stability of the closed loop system with saturated control. We present here an approach to this problem based on the Lyapunov function method. The domain of attraction of the origin is obtained and it is shown that the system stability is ensured by simply choosing a particular compensator design which solves RSP. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
108.
[2,2-dimethyl-4-(t-butyldimethylsiloxy)-3,4-dihydro-2H-pyran-6-yl] methanal (1) was synthesized from commercially available butopyronoxyl (2). The selectivity of reducing agents such as DIBAL-H and LiAlH4 towards butopyronoxyl was studied. Solvent effects were found to influence 1,2 versus 1,4 reduction. 相似文献
109.
Marcela Stoia Oana ?tef?nescu Gabriela Vlase Lucian Barbu-Tudoran Mirela Barbu Mircea ?tef?nescu 《Journal of Sol-Gel Science and Technology》2012,62(1):31-40
This paper presents a study regarding the formation of hybrid gels starting from tetraethyl orthosilicate (TEOS), polyvinyl
alcohol (PVA) and 1,3-propanediol (PD) and their thermal evolution to mesoporous silica matrices. The possibility of obtaining
homogenously dispersed cobalt ferrite inside the silica matrix starting from (TEOS–PVA–PD–Metal Nitrates) gels was also studied.
The formation of the hybrid gels TEOS/PVA/PD with different compositions was studied by FT-IR spectrometry and thermal analysis,
in order to evidence the interaction between the diol with the organic and the inorganic polymers. Both thermal analysis and
FT-IR spectrometry have evidenced the formation of physical and chemical interaction between polyols and the siloxane network.
Elemental mapping performed by SEM-EDX technique evidenced the formation of homogenous hybrids both in the presence of the
absence of 1,3-propanediol. SEM images of the powders obtained by annealing the hybrid xerogels at 600 °C have evidenced the
formation of mesoporous silica. By thermal treatment of the (TEOS–PVA–PD–Metal Nitrates) gels, 30%CoFe2O4/70%SiO2 (mass percent) nanocomposites uniformly dispersed in silica matrix with characteristic magnetic properties, have been successfully
synthesized. 相似文献
110.
Ana‐Maria Gurban Lucian Rotariu Virgil Emanuel Marinescu Camelia Bala 《Electroanalysis》2012,24(12):2371-2379
A ternary composite material based on Prussian blue, single‐walled carbon nanotubes and 1‐butyl‐3‐methylimidazolium hexafluorophosphate was prepared and tested for electrochemical detection of H2O2. The sensor allows amperometric detection of H2O2 at ?0.05 V, with a sensitivity of 137 mA M?1?cm?2. The nanocomposite provides a favorable microenvironment for immobilization of horseradish peroxidase (HRP). Determination of xenoestrogenic compounds was performed by enzymatic oxidation at the surface of modified screen printed biosensor in the presence of H2O2. The developed electrochemical biosensors exhibited high sensitivity, low detection limits, good operational and storage stability, for detection of 4‐t‐butylphenol, 4‐t‐octylphenol, 4‐n‐nonylphenol and 4‐n‐nonylphenol ethoxylate. 相似文献