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91.
Poornachandran R. Mohan Kumar N. Saravana Kumar R. Baskaran S. 《Microsystem Technologies》2021,27(11):4101-4109
Microsystem Technologies - The quantitative analysis of microwave noise available in the double gate (DG) high electron transistors of mobility (HEMT) is reported in this paper. For this analysis,... 相似文献
92.
Microsystem Technologies - 相似文献
93.
Microsystem Technologies - In this article, a rectangular solid-core photonic crystal fiber (PCF) is proposed as temperature sensor. The air-holes of the PCF have been filled with Ethyl alcohol... 相似文献
94.
Efficient compression and network adaptive video coding for distributed video surveillance 总被引:1,自引:1,他引:0
The availability of cheap network based video cameras and the prevalence of wireless networks has lead to a major thrust towards
deployment of large scale Distributed Video Surveillance (DVS) systems. This has opened up an important area of research to
deal with the issues involved in DVS system for efficient collection and transmission of large scale video streams from the
cameras at the guarded sites, to the end users in possibly constrained network conditions. In this paper, we propose a framework
based on content-based video classification and scalable compression scheme to provide a robust bandwidth efficient video
transmission for DVS. The scheme builds on a Discrete Wavelet Transform (DWT) based Color-Set Partitioning for Hierarchical
Trees (CSPIHT) coding to obtain a scalable bitstream. Wavelet domain segmentation and compression assists in development of
a DVS architecture. The architecture includes a novel module for dynamic allocation of Network bandwidth based on the current
available resources and constraints. Different frame constituents are optimally coded based on their relative significance,
perceptual quality, and available estimate of network bandwidth. Experimental result over different video sequences and simulations
for Network conditions demonstrate the efficient performance of the approach. 相似文献
95.
In this paper we have proposed a dynamic pricing scheme for the contributing peers in the Video on Demand (VoD) system. The
scheme provides an effective mechanism to maximize the profit through the residual resources of the contributing peers. A
utilization function is executed for each contributing peer to estimate the utility factor based on the parameters such as
initial setup cost, holding cost, chaining cost and salvage cost. In this paper, we urge an effective dynamic pricing algorithm
that efficiently utilizes a range of parameters with a varying degree of complexity. The key findings of the algorithm are
(i) each contributing peers are benefitted by the monetary based on its resource contributions to the VoD system and (ii)
a high degree of social optimum is established by proficiently aggregating the contributing peer’s resources with the overall
resources of the VoD system. We validate our claim by simulating the proposed dynamic pricing scheme with other standard pricing
schemes such as altruism, cost model and game theory perspective. The result of our dynamic pricing scheme shows the best
utility factor than other standard pricing schemes. 相似文献
96.
This paper presents OS-Guard(On-Site Guard), a novel on-site signature based framework for multimedia surveillance data management. One of the major concerns in widespread
deployment of multimedia surveillance systems is the enormous amount of data collected from multiple media streams that need
to be communicated, observed and stored for crime alerts and forensic analysis. This necessitates investigating efficient
data management techniques to solve this problem. This work aims to tackle this problem, motivated by the following observation,
more data does not mean more information. OS-Guard is a novel framework that attempts to collect informative data and filter out non-informative data on-site, thus
taking a step towards solving the data management problem. In the framework, both audio and video cues are utilized by extracting
features from the incoming data stream and the resultant real valued feature data is binarized for efficient storage and processing.
A feature selection process based on association rule mining selects discriminant features. A short representative sample
of the whole database is generated using a novel reservoir sampling algorithm that is stored onsite and used with an support
vector machine to classify an important event. Initial experiments for a Bank ATM monitoring scenario demonstrates promising
results. 相似文献
97.
Arup Kumar Nandi Shubhabrata Datta Kalyanmoy Deb 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(6):989-1008
Polyurethane is used for making mould in soft tooling (ST) process for producing wax/plastic components. These wax components are later used as pattern in investment casting process. Due to low thermal conductivity of polyurethane, cooling time in ST process is long. To reduce the cooling time, thermal conductive fillers are incorporated into polyurethane to make composite mould material. However, addition of fillers affects various properties of the ST process, such as stiffness of the mould box, rendering flow-ability of melt mould material, etc. In the present work, multi-objective optimization of various conflicting objectives (namely maximization of equivalent thermal conductivity, minimization of effective modulus of elasticity, and minimization of equivalent viscosity) of composite material are conducted using evolutionary algorithms (EAs) in order to design particle-reinforced polyurethane composites by finding the optimal values of design parameters. The design parameters include volume fraction of filler content, size and shape factor of filler particle, etc. The Pareto-optimal front is targeted by solving the corresponding multi-objective problem using the NSGA-II procedure. Then, suitable multi-criterion decision-making techniques are employed to select one or a small set of the optimal solution(s) of design parameter(s) based on the higher level information of the ST process for industrial applications. Finally, the experimental study with a typical real industrial application demonstrates that the obtained optimal design parameters significantly reduce the cooling time in soft tooling process keeping other processing advantages. 相似文献
98.
In this paper a new estimation approach combining both Recursive Least Square (RLS) and Bacterial Foraging Optimization (BFO) is developed for accurate estimation of harmonics in distorted power system signals. The proposed RLS–BFO hybrid technique has been employed for estimating the fundamental as well as harmonic components present in power system voltage/current waveforms. The basic foraging strategy is made adaptive by using RLS that sequentially updates the unknown parameters of the signal. Simulation and experimental studies are included justifying the improvement in performance of this new estimation algorithm. 相似文献
99.
Anil Kumar William R. Leo Lawrence Green Gene L. Woodruff 《Journal of Fusion Energy》1989,8(1-2):107-126
The neutron spectra transmitted across a fission-suppressed hybrid blanket and its components, driven by a low intensity 14 MeV Haefely neutron generator, were measured with a 2×2 NE213 detector at LOTUS facility. These experiments have been analyzed with 2D and 3D codes DOT3.5 and MCNP, respectively. The spectral integrals between 15 to 1 MeV show good agreement among the 2D, the 3D, and the NE213 for 15 cm lead, 18 cm beryllium, and 25 cm graphite slabs. However, there are large discrepancies for 6.2 cm stainless steel and 15 cm lithium carbonate slabs. The assemblies involving two or more of these slabs reflect these tendencies. We observe also considerable disagreement over pointwise spectra for a number of assemblies.Work done while on visiting assignment to Institut de Génie Atomique, E.P.F.L. 相似文献
100.
A mathematical model for the transient heat flow analysis in arc-welding processes is proposed, based on a unique set of boundary conditions. The model attempts to make use of the relative advantages of analytical as well as numerical techniques in order to reduce the problem size for providing a quicker solution without sacrificing the accuracy of prediction. The variation of thermo-physical properties with temperature has been incorporated into the model to improve the thermal analysis in the weld and heat-affected zones. The model has been evaluated using a five-point explicit finite difference method for analysing the welding heat flow in thin plates of two different geometric configurations. The temperature distribution closer to the heat source, primarily in the weld zone and the heat-affected zones, are predicted by the numerical technique. The thermal characteristics beyond the heat-affected zone are amenable to standard analytical techniques. The behaviour of the boundary condition in the model has been investigated in detail.Nomenclature
q
Rate of heat per unit thickness (Wm–1)
-
d
Plate thickness (m)
-
v
Velocity of source (m s–1)
-
t
Time (s)
-
T
Temperature value at the desired point (K)
-
T
0
Initial temperature (K)
-
K
Thermal conductivity (W m–1 K–1)
-
Density (kg m–3)
-
c
p
Specific heat (J kg–1 K–1)
-
Thermal diffusivity (m2 s–1)
-
n
-
Distance of point considered from the source (=x–vt) (m)
-
K
0
Modified Bessel function of second kind and zero order
-
r
Radial distance from the source (r=(x
2+y
2)1/2) (m)
-
Model width (m)
-
a
Plate width (m)
-
Distance from the source =(2+4 ×10–4)1/2 (m)
- n
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