1,248 research outputs found
Development of a creep data base management system for engineering materials
A fully menu driven creep data base management system has been developed for various high temperature materials using the client /server (C/S) architecture with Sybase system. 10 as backend and power builder 4.0 as an inter-face. The relational data base constitutes of various classes of materials, their heat treatment, prior history and the related creep properties at different test condit-ions, in addition to the source process route and chemical composition details.Top-down approach has been adopted in designing the entity-relationship (E-R) model. The creep data is organized into the third normal form, and the
entire system is divided into manageable modules. Coding for the system is done using Transact-SQL for data defin- ition, manipulation and control operations, and power script language for application development. This article briefly outlines the formulation of data base design, and the implemented E-R model, in addition , to the prese-ntation of various screen formats used for data entry and retrieval modules
Study of Variation in Upper Air Density Over India
The paper presents the seasonal variations and distribution of atmospheric density in the upper air over Indian region. The study reveals the density gradient has a down slope from North to South during winter and South to North, upto 200 mb level in summer. At 850 mb level the isopyenic lines forms a shallow through over East coast and at 700 mb level Bombay-Poona region while over the rest of the country the isopyenics show no special features. At 500 mb level three is a well marked trough of density over North Western India. Above 200 mb level an altogether different picture throughout the year is noticed
A NEW SPEECH ENHANCEMENT TECHNIQUE USING PERCEPTUAL CONSTRAINED SPECTRAL WEIGHTING FACTORS
This paper deals with musical noise result from perceptual speech enhancement type algorithms and especially wiener filtering. Although perceptual speech enhancement methods perform better than the non perceptual methods, most of them still return annoying residual musical noise. This is due to the fact that if only noise above the noise masking threshold is filtered then noise below the noise masking threshold can become audible if its maskers are filtered. It can affect the performance of perceptual speech enhancement method that process audible noise only. In order to overcome this drawback here proposed a new speech enhancement technique. It aims to improve the quality of the enhanced speech signal provided by perceptual wiener filtering by controlling the latter via a second filter regarded as a psychoacoustically motivated weighting factor. The simulation results shows that the performance is improved compared to other perceptual speech enhancement method
Dispersive Wave Analysis – Method and Applications
A technique for estimating the dispersion characteristics of propagating waves as measured by an array is detailed. The technique consists of bandpass filtering the data through a filterbank and then processing the filtered waveforms non-dispersively. The results can show the dispersion of the entire time series or be parsed in time to analyze the dispersion characteristics of any section of the time series. Processing LWD field data shows that this method can extract dispersion characteristics over a broadband of frequencies and with low amplitude signals. Both the field data and laboratory scale data show that multiple modes present over the same frequency band can be identified.Halliburton CompanyMassachusetts Institute of Technology. Earth Resources LaboratoryMassachusetts Institute of Technology. Borehole Acoustics and Logging Consortiu
Development of efficient techniques for ASR System for Speech Detection and Recognization system using Gaussian Mixture Model- Universal Background Model
Some practical uses of ASR have been implemented, including the transcription of meetings and the usage of smart speakers. It is the process by which speech waves are transformed into text that allows computers to interpret and act upon human speech. Scalable strategies for developing ASR systems in languages where no voice transcriptions or pronunciation dictionaries exist are the primary focus of this work. We first show that the necessity for voice transcription into the target language can be greatly reduced through cross-lingual acoustic model transfer when phonemic pronunciation lexicons exist in the new language. Afterwards, we investigate three approaches to dealing with languages that lack a pronunciation lexicon. Secondly, we have a look at the efficiency of graphemic acoustic model transfer, which makes it easy to build pronunciation dictionaries. Thesis problems can be solved, in part, by investigating optimization strategies for training on huge corpora (such as GA+HMM and DE+HMM). In the training phase of acoustic modelling, the suggested method is applied to traditional methods. Read speech and HMI voice experiments indicated that while each data augmentation strategy alone did not always increase recognition performance, using all three techniques together did. Power normalised cepstral coefficient (PNCC) features are tweaked somewhat in this work to enhance verification accuracy. To increase speaker verification accuracy, we suggest employing multiple “Gaussian Mixture Model-Universal Background Model (GMM-UBM) and SVM classifiers”. Importantly, pitch shift data augmentation and multi-task training reduced bias by more than 18% absolute compared to the baseline system for read speech, and applying all three data augmentation techniques during fine tuning reduced bias by more than 7% for HMI speech, while increasing recognition accuracy of both native and non-native Dutch speech
A Computational Teddqae for Heat W a r h e to a Fast Movhg Hl(lf 80urce
The heat transfer in the two phase region in the study of melting and solidification of a surface layer by a moving heat source is studied.The transient problem is formulated using the enthalpy and temperature model and solved in an oblate spheroidal co-ordinate system using animplicit modified upwinding scheme in terms of non-dimensional nodal enthalpy and temperature. It is observed that the temperature gradient which controls the solidification rate, increases to a maximum initiallyand then decreases to zero. It is found that the solid-liquid interface velocity which is zero initially very quickly reaches to the velocity ofthe heat source, though the gradient ahead of the interface relaxes much more slowly
PHARMACOKINETIC DRUG INTERACTIONS OF GLICLAZIDE AND ITOPRIDE IN NORMAL AND DIABETIC RATS
Objective: The present study was aimed to investigate the safety, reliability of Gliclazide and possible drug interaction with Itopride when they were administered as combination treatment.Methods: Studies were conducted in normal and streptozotocin induced diabetic rats with oral administration of selected doses of gliclazide, itopride and their combination. Blood samples were collected from rats by retro orbital/marginal ear vein puncture at regular intervals of time. All the blood samples were analyzed for pharmacokinetic parameters by HPLC method.Results: There was no significant difference in pharmacokinetic parameters of both Gliclazide alone and combination with itopride in healthy and diabetic rats on day 1 and day 8.Conclusion: Based on the results it can be concluded that the concurrent administration of these two drugs have potential benefit without any drug interactions in the effective management of diabetes and gastroparesis.Ă‚
Scanning Electron Probe Microanalysis
Scanning electron probe microanalysis has grown over the pastthree decades into a powerful technique for the microchemicalcharacterisation of materials. This paper describes the principles andvarious features of a typical microanalyser, and illustrates its uniquecapabilities in the study of materials by means of selected case histories
Geomechanical Modeling of In-Situ Stresses Around a Borehole
In this paper, we present a modelling of the in-situ stress state associated with the severe hole
enlargement of a wellbore.
Geomechanical information is relevant to assure wellbore stability, i.e., to prevent damages in the
formation and later on, the casing. Many of the drilling parameters, as mud weight or the optimal
orientation of the borehole, require some knowledge of the mechanical behaviour of the rock. The lack of
these kind of data in exploratory areas, where there are usually insufficient constraints for the geological
model, increases even more the risk, hence the costs.
The present model uses the concepts of poroelasticity theory to compute the stationary 2D, brittle
response of the formation around a borehole that is submitted to effective compressive horizontal stresses.
The numerical solution is obtained using a finite element approximation.
The initial stress state at the far field was estimated combining a frictional-failure theory with the
observations of dipmeter caliper in a particular borehole that presents elongations in a preferential direction.
The direction and relative extension of the observed breakouts at a particular depth are modelled
successfully using formation realistic parameters and dimensions, although the exact shape of the borehole
(at all angles) was unknown. For the particular case study, the orientation of the breakout is NE-SW, at
about 82 degrees azimuth. Therefore, the maximum horizontal stress lies at approximately 350 degrees
azimuth. The ratios of horizontal principal stresses to vertical stress that best honor the observations
are SHmax = 2.3Sv and Shmin = 1.7Sv. The compressive strength necessary for the rock to fail, as
indicated by the caliper data under this stress field, is about 140 MPa.Massachusetts Institute of Technology. Borehole Acoustics and Logging ConsortiumMassachusetts Institute of Technology. Earth Resources Laborator
Effects of source mismatch on multipole Logging
The effects of mismatched multipole sources were investigated. Multipole sources considered here are those that they are
constructed of monopoles with appropriate sign combination. To simulate mismatched dipole and quadrupole sources, we made the
amplitude of one of monopoles smaller than those of the other monopoles. The dipole and quadrupole component were obtained with
four monopole receiver array system by subtracting or adding appropriate responses. Mismatched dipole source excites nondipole
modes in addition to the flexural mode. The strongest of these is the Stoneley mode, whose amplitude increases with increasing
mismatch. Similarly, mismatched quadrupole sources produce nonquadrupole modes such as the Stoneley mode in addition to the
screw mode. The amplitude of the Stoneley mode increases with mismatch. However, we can obtain the flexural mode by A-C and the
screw mode by A-B+C-D processing, respectively. The Stoneley mode, which has the same amplitude at the same radial position from
the borehole axis, is cancelled out by A-C and A-B+C-D processing as long as the tool is placed at the center of the borehole.Massachusetts Institute of Technology. Earth Resources LaboratoryMassachusetts Institute of Technology. Borehole Acoustics and Logging Consortiu
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