Search results

Mathematical models for channel are considered for various communication functions like, predicting radio coverage, estimation of interferences from various sources, estimating the characteristics of an alternate transmitter and receiver, achievable data rates and for determining the location for wireless infrastructure.
Fading is due combination of multipath propagation and Doppler shift frequency.The paper proposes a modification in the ubiquitous OFDM often used for high data rate application using wavelets and compares the performance with conventional OFDM.
OFDM System The demand for channels that provides allowable (BER) Bit Error Rate, High data rates and minimum delay has increased manifold; OFDM (Fig.1)is one such technique which offers high data rate and is used in (DAB) Digital Audio Broadcasting, (DVB) Digital Video Broadcasting and (ADSL) Asymmetric Digital Subscriber Line[7,8].
OFDM splits a high data rate stream into a number of lower rate schemes that are simultaneously transmitted over a number of subcarriers.
The output of each filter contains half the frequency content but equal amount of samples as the input signal but double the amount of data.

The data-weighted averaging (DWA) algorithm can reduce static current source mismatch effects, but it increases the effects of glitch energy.
This is because the TC switching scheme produces a data-dependent output signal.
By implementing the OES switching scheme, the output signal is indirectly changed from data-dependent to clock-dependent.
Temes, Understanding Delta-Sigma Data Converters, Wiley (2005)
Temes, “A Segmented Data-Weighted-Averaging Technique”, IEEE International Symposium on Circuits and Systems, New Orleans, LA, pp. 481-484, May 2007

Experimental data indicate that the proposed method does not negatively affect to the surface integrity and the process validity has been verified.
Moreover,conventional methods of delivering grinding fluid, i.e. flood delivery via a shoe or jet delivery tangential to the wheel via a nozzle, are not believed to fully penetrate this boundary layer and, thus, the majority of the grinding fluid is deflected away from the grinding zone[2].Therefore, the flood delivery of a grinding fluid not only increases hydrodynamic lift force, results in reduction in the depth of cutting, and increases grinding wheel spindle distortion, but also entails high costs in production and creatse several techno-environmental problems, biological problems, and soil contamination during disposal.
The drastic reduction or even the complete elimination of this fluid can undoubtedly lead to higher temperatures in the process, causing reduced cutting tool output, loss of dimensional and geometrical precision of the workpieces and variations in the machine thermal behavior.
When abrasive tools are used, a reduction in grinding fluid may make it difficult to keep the grinding wheel pores clean, favoring the tendency for clogging and thus strongly contributing to the aforementioned negative factors[3].

The model itself must decide what features it will use to group the input data.
These series of nodes represents operations to be performed on the data, while links between the nodes indicate the direction of data flow.
The first node in the stream is source node which is importing data.
Field properties, specified in a source node or in a separate type node are defining data type and dividing the imported data into inputs and outputs.
Wilkinson, Tree Structure Data Analysis.

To solve the problem of so-called dimensionality disaster, reasonable dimensionality reduction or attribute extraction must be implemented to data set.
Because the treatment for incremental data are batching in these algorithms,which break the original data structures and re start the process of the algorithm, so the algorithm’s efficiency is greatly reduced.
The projection transformation can not only keep local geometrical characteristics of the data, but also quickly gain low dimensional expression of new incremental data.
Given, is the data dimension, the euclid distance between any two points and is .
Data extraction and processing based on PCA projection.

Whereas scaling of neural predictor input data uses signal obtained for 100% relative depth defect.
Those additional data were calculated using polynomial and Gaussian approximation of U(x).
Data and adapted neural model are recorded.
Application of adaptive step enables three times reduction of inspection time in comparison to short fixed step.
Concluding: an application of proposed adaptive step enable significant reduction of inspection time, simultaneously keeping the signal reconstruction error RMSE very low (Fig. 5a).

Thus there is a considerable reduction in crystallite size to the nanometre range is obtained, which is the desired one.These nanosized Titanium is used for hot consolidation in the forthcoming steps.
(b) shows the XRD pattern of Yttria and the corresponding three maximum peaks are obtained at 29.40, 48.80 and 34.030 , which is evident from the JCPDS diffraction data.
Similarly the XRD pattern of Fe showing the peak broadening and reduction in crystallite size is shown in Fig.2.
The discussion made above and in the forthcoming sections is based on the JCPDS diffraction data. 3(a) 3(b) 3(c) 3(d) Fig. 3.
The pattern shows the presence of all these elements and the indexing has been done using the JCPDS for diffraction data. 4(a) 4(b) 4(c) Fig. 4.

.: dissolved oxygen, ORP: Oxidation Reduction Potential; # contaminated site with operational mine, + Non contaminated site, * Mines under construction mine sites but more importantly allow us to decipher the microbe mediated biogeochemical processes and design suitable remediation strategies using native microbial systems.
Dissolved oxygen content, conductivity, salinity and oxidation reduction potential of the samples were determined.
Relative abundance of different bacterial phyla The total number of cultivable microorganisms (CFU = colony forming units) as determined by plating on various media that supports growth of chemoheterotrophic and chemolithotrophic bacteria reveals considerable numbers (in the order of 10 6 to 10 9 CFU per mL sample, data not shown) of bacteria in all samples.
The 16S rRNA gene sequences are used for similarity search and sequence match in NCBI GeneBank and Ribosomal Data base project (II).
The ARDRA data showed that a considerable diversity exist in U mine pit and T-Tail samples with 44 OTUs out of 73 clones for the U Pit and 15 OTUs from 25 clones, respectively.

In the present article the data, received at carrying out of trial tests of biohydrometallurgical method of heap leaching of CCF flotation tailings on a heap in weight of 5400 tons which has been generated on experimental ground near to tailing dump № 1 at the territory of AMMC are submitted.
The material reduction makes 85% of class - 0.15 mm.
As data of mineralogical and substantial composition of the heap tailings dumps show, in quantitative ratio as main sulphide minerals there were pyrite, chalcopyrite, chalkozin, kovelin, bornite, galena and sphalerite.
According to data of phase analysis of BL cakes the chalcopyrite oxidation makes more than 62%, and pyrite - 87-92%.
The maintenance of high number of acidophilic bacterial association in winter period testifies about high viability of bacteria and and activity of the oxidation-reduction reactions occurring in a heap and raising temperature in a material of a heap.

In addition to the stress and strain data, acoustic emission was used to investigate the degree of damage and record its growth.
From the data in Fig. 1, it can be seen that Specimen NN had the highest number of hits in its high peak amplitude (> 70 dB), and as the damage in the concrete grew, the magnitude of the highest peak amplitude also increased.
In addition, Specimen RN exhibited a very low AE energy capacity (< 20 eu) for duration times > 4 ms, because the effect of duration time on the AE energy is decreased owing to a reduction in the dissipation of stress and a reduction in the damage tolerance capacity.
(3) Based on the Kaiser effect and the felicity ratio data, it is confirmed that microcracking in recycled aggregate concrete specimens occurs at lower stress levels than in normal concrete, and therefore, recycled aggregate concrete specimens have lower damage tolerance under cyclic loading conditions than normal concrete does.