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31.
This paper proposes a new feature extraction technique using wavelet based sub-band parameters (WBSP) for classification of unaspirated Hindi stop consonants. The extracted acoustic parameters show marked deviation from the values reported for English and other languages, Hindi having distinguishing manner based features. Since acoustic parameters are difficult to be extracted automatically for speech recognition. Mel Frequency Cepstral Coefficient (MFCC) based features are usually used. MFCC are based on short time Fourier transform (STFT) which assumes the speech signal to be stationary over a short period. This assumption is specifically violated in case of stop consonants. In WBSP, from acoustic study, the features derived from CV syllables have different weighting factors with the middle segment having the maximum. The wavelet transform has been applied to splitting of signal into 8 sub-bands of different bandwidths and the variation of energy in different sub-bands is also taken into account. WBSP gives improved classification scores. The number of filters used (8) for feature extraction in WBSP is less compared to the number (24) used for MFCC. Its classification performance has been compared with four other techniques using linear classifier. Further, Principal components analysis (PCA) has also been applied to reduce dimensionality. 相似文献
32.
The aim of this project was to investigate the potential of reducing number of mixers in the biological treatment process and thereby achieve energy and economical savings and contribute to cleaner environment. The project was carried out at Avedoere wastewater treatment plant and a full scale investigation was conducted to study the effect of reduced mixing on flow velocity, suspended solid sedimentation, concentration gradients of oxygen and SS with depth and treatment efficiency. The only negative effect observed was on flow velocity; however the velocity was above the critical velocity. The plant has been operating with 50% of its designed number of mixers since September 2007 and long term results also confirm that reduced mixing did not have any negative effect on treatment efficiency. The estimated yearly electricity saving is 0.75 GWh/year. 相似文献
33.
Decentralised water supply systems are becoming increasingly affordable and commonplace in Australia and have the potential to alleviate urban water shortages and reduce pollution into natural receiving marine and freshwater streams. Learning processes are necessary to support the efficient implementation of decentralised systems. These processes reveal the complex socio-technical and institutional factors to be considered when developing an enabling environment supporting decentralised water and wastewater servicing solutions. Critical to the technological transition towards established decentralised systems is the ability to create strategic and adaptive capacity to promote learning and dialogue. Learning processes require institutional mechanisms to ensure the lessons are incorporated into the formulation of policy and regulation, through constructive involvement of key government institutions. Engagement of stakeholders is essential to the enabling environment. Collaborative learning environments using systems analysis with communities (social learning) and adaptive management techniques are useful in refining and applying scientists' and managers' knowledge (knowledge management). 相似文献
34.
This paper settles a question about prudent vacillatory identification of languages. Consider a scenario in which an algorithmic deviceM is presented with all and only the elements of a languageL, andM conjectures a sequence, possibly infinite, of grammars. Three different criteria for success ofM onL have been extensively investigated in formal language learning theory. IfM converges to a single correct grammar forL, then the criterion of success is Gold's seminal notion ofTxtEx-identification. IfM converges to a finite number of correct grammars forL, then the criterion of success is calledTxtFex-identification. Further, ifM, after a finite number of incorrect guesses, outputs only correct grammars forL (possibly infinitely many distinct grammars), then the criterion of success is known asTxtBc-identification. A learning machine is said to beprudent according to a particular criterion of success just in case the only grammars it ever conjectures are for languages that it can learn according to that criterion. This notion was introduced by Osherson, Stob, and Weinstein with a view to investigating certain proposals for characterizing natural languages in linguistic theory. Fulk showed that prudence does not restrictTxtEx-identification, and later Kurtz and Royer showed that prudence does not restrictTxtBc-identification. This paper shows that prudence does not restrictTxtFex-identification. 相似文献
35.
Baranwal Alok Kumar Sharma Shashibhushan Roy Sanjay Dhar Kundu Sumit 《Wireless Personal Communications》2022,124(2):1281-1296
Wireless Personal Communications - This paper proposes and analyses the power allocation coefficient normalization for successive interference cancellation in power-domain non-orthogonal multiple... 相似文献
36.
The present article is concerned with the investigation of disturbances in a homogeneous transversely isotropic thermoelastic rotating medium with two temperatures, in the presence of the combined effects of Hall currents and magnetic field. The formulation is applied to the thermoelasticity theories developed by Green-Naghdi theories of type-II and type-III. Laplace and Fourier transform techniques are applied to solve the problem. The analytical expressions of displacements, stress components, temperature change, and current density components are obtained in the transformed domain. A numerical inversion technique has been applied to obtain the results in the physical domain. Numerical simulated results are depicted graphically to show the effect of Hall current and two temperatures on resulting quantities. Some special cases are also deduced from the present investigation. 相似文献
37.
38.
Chromatic effects of radial gradient-index materials have been analyzed, and several important conclusions have been derived in terms of material dispersion data. The use of Buchdahl dispersion data, both for base glass materials and ion-exchange pairs, provides some simple relationships for chromatic aberration and helps in selecting suitable materials for producing achromatic radial gradient-index lenses. 相似文献
39.
1. Lamotrigine is a new antiepileptic drug, chemically unrelated to currently used antiepileptic medication. Its pharmacokinetics can be influenced by concomitant antiepileptic medication. 2. This study was performed to assess the pharmacokinetic profile of lamotrigine in three groups of children treated with different types of comedication: drugs known to induce, to inhibit or to have no clinically significant influence on drug metabolism, respectively. 3. Thirty-one children aged 6 months to 5 years were included and received a 2 mg kg-1 single oral dose. Lamotrigine plasma profiles were different between the three comedication groups. The half-lives (mean +/- s.d.) were: 7.7 +/- 1.8 h, 21.9 +/- 6.8 h, 44.7 +/- 10.2 h in the "inducer', "other' and "inhibitor' groups respectively. 4. Patients were then dosed to steady state, with the dosage adjusted on the basis of the single dose pharmacokinetics to achieve a minimum plasma concentration between 1.5 and 3 mg l-1. The mean minimum plasma concentration for the three groups was 2.54 +/- 1.28 mg l-1 at steady state. 5. Dosage of lamotrigine can be optimised with knowledge of the metabolic effects of antiepileptic comedication. 相似文献
40.
Navigating growth cones need signal transduction machinery to amplify and transmit the effects of extracellular signals throughout the growth cone. In culture, many drugs that affect second messengers are known to modulate neurite extension (with different effects on different neurons), and gradients of calcium influx and cyclic nucleotide analogs can cause growth cones to turn. However, it is not clear which of these responses are physiologically relevant, as axons grow through much more complex environments in vivo. The "exposed brain" preparation in Xenopus embryos provides an experimentally tractable system in which it is possible to study growth, pathfinding, and target recognition of retinal growth cones in vivo, while pharmacologically manipulating their signal transduction systems. These growth cones can also be easily studied in explant culture. We describe preliminary results of parallel in vivo and in vitro experiments using an array of drugs that perturb transduction molecules. Surprisingly, calcium ionophores and cyclic nucleotide analogs have no significant effect on retinal axon growth or pathfinding. Several agents including herbimycin A, ML-7, mastoparan, and RHC80267 inhibit retinal axon growth, both in vivo and in vitro, suggesting that tyrosine kinases, myosin, heterotrimeric G-proteins, and diacylglycerol lipase are important for retinal growth cones navigating in the optic pathway. 相似文献