Mechanical Engineering,Feat

Hidden Markov models (HMM) with Gaussian mixture observation densities are the dominant approach in speech recognition. These systems typically use a representational model for acoustic modeling which can often be prone to overfitting and does not translate to improved discrimination. We propose a new paradigm centered on principles of structural risk minimization using a discriminative framework for speech recognition based on support vector machines (SVMs). SVMs have the ability to simultaneously optimize the representational and discriminative ability of the acoustic classifiers. We have developed the first SVM-based large vocabulary speech recognition system that improves performance over traditional HMM-based systems. This hybrid system achieves a state-of-the-art word error rate of 10.6% on a continuous alphadigit task -a 10% improvement relative to an HMM system. On SWITCHBOARD, a large vocabulary task, the system improves performance over a traditional HMM system from 41.6% word error rate to 40.6%. This dissertation discusses several practical issues that arise when SVMs are incorporated into the hybrid system.

In this paper the integrated process of biomass gasification and a solid oxide fuel cell (SOFC) was studied in terms of thermodynamics. The study is based on an ongoing project intending to develop an innovative sustainable technology with high efficiency. According to some assumptions, the energy balance revealed that the process can be auto-thermal. Furthermore, and due to the utilization of the hydrogen content of steam utilized in the reforming stage, the overall efficiencies to electrical power could reach very high levels. ᭧

This paper presents the kinematic and dynamic analysis of slider crank mechanism. The slider crank mechanism is simulated in ADAMS software to observe the response of the slider block and the reaction forces at joint R 2 (joint between crank shaft and connecting rod). The dynamic analysis has been performed by applying moment of 4.2 Nm at joint R 1 (the revolute joint between connecting shaft and connecting plate). The applied moment is removed by imposing rotational motion at joint R 1 with angular velocity of 6 rad/sec to perform dynamic analysis. These simulations were performed with different time steps and durations. The friction was assumed to be negligible during these simulations. As a result of this work, the longitudinal response of the slider block is observed with applied moment as well as slider block response along with reaction forces at joint R 2 is investigated in case of imposed rotational motion.

The natural method includes the utilization of ice or snow obtained naturally in cold climate. Ice melts at 0 0 C. So when it is placed in space or system warmer than 0 0 C, heat is absorbed by the ice and the space is cooled. The ice then melts into water by absorbing its latent heat at the rate of 324 kJ/kg. But, now-a-days, refrigeration requirements have become so high that the natural methods are inadequate and therefore obsolete.

This paper presents the results of investigations carried
on CRDI system assisted diesel engine using diesel
blended with Iron (II, III) Oxide nanoparticles. The iron
(II, III) Oxide nanoparticles was mixed with diesel in
mass fraction of 25 and 50 ppm with the help of
mechanical homogenizer and an ultrasonicator. The
experiment was carried out with the aim of obtaining
comparative measures of combustion and emission
parameters to evaluate the behavior of the CRDI diesel
engine running on the diesel and iron (II, III) Oxide
nanoparticles blended modified diesel. It was observed
that iron (II, III) Oxide nanoparticles blended diesel
exhibit a significant reduction in specific fuel
consumption and exhaust emission at all operating loads.
The results also showed a significant enhancement in
brake thermal efficiency and heat release rate due to
influence of iron (II, III) Oxide nanoparticles addition in
diesel.

This paper presents the testing of a catalytic converter coated with aluminium oxide nanoparticles as catalyst to be used in the conventional catalytic converter. The catalytic converter was developed based on catalyst materials consisting of metal oxides such as aluminium oxide nano particles (Al2o3). The catalyst material (Al2o3) is inexpensive in comparison with noble catalysts such as platinum or palladium. In addition, the noble metals such as platinum group metals are now recognized as human health risk due to their exhaust emissions in the environment from the conventional catalytic converter. It is experimentally found that the conversion efficiencies of Al2o3 based catalytic converter are 99.5%, 92% for CO and HC emissions respectively. The objective of this paper is to develop a low cost three way catalytic converter to be used with the DI diesel engine.

This paper reports on the use of aluminium oxide nanoparticles (AONP) as additive to the diesel fuel and its effects of performance and emission characteristics of the CRDI diesel engine coupled with an eddy current dynamometer and a data acquisition system. The nanoparticles added to diesel in different proportions (25ppm and 50ppm) using a mechanical homogenizer and an ultrasonicator. The aluminium oxide nanoparticles act as an oxygen donating catalyst and provide oxygen for the oxidation of CO and hydrocarbons (HC). The results also showed considerable improvement in brake thermal efficiency due to the influence of the aluminium oxide nanoparticles addition in diesel fuel. The tests revealed that aluminium oxide nanoparticles can be used as additive in diesel to mitigate the exhaust emissions significantly.

This paper reports on the use of cerium oxide nanoparticles (CEONP) as additive to the diesel fuel and the effects of their operational characteristics like performance and emission of the DI diesel engine. In this study, the tested fuels were prepared by blended cerium oxide nanoparticles into the diesel fuel at the mass fraction of 25ppm and 50ppm with the help of a mechanical homogenizer and an ultrasonicator. Based on the experimental results, HC, CO emissions and smoke noticeably decrease, while NOx emission dramatically increases with increasing the dosing level of cerium oxide nanoparticles. At the full load, the magnitude of HC and CO for the neat diesel was 104 ppm and 51 (% by volume), whereas it was 68 ppm and 20 (% by volume) for the CMNT50 fuel, respectively. The results also showed a significant enhancement in brake thermal efficiency and heat release rate due to the influence of the cerium oxide nanoparticles addition in diesel.

This paper reports on the use of carbon multiwalled nanotubes
as additive to the diesel fuel and the effects of their operational
characteristics and performance, emission and combustion characteristics
of the CRDI system assisted diesel engine. In this study, the tested fuels
were prepared by dispersing carbon multiwalled nanotubes into the
diesel fuel at the mass fraction of 25 and 50 ppm with the help of a
mechanical homogenizer and an ultrasonicator. Experimental results
showed that the flash points and cetane number of the fuels dispersed
with carbon multiwalled nanotubes have increased with higher
concentration of carbon multiwalled nanotubes. Based on the
experimental results, NOx emissions and smoke noticeably decrease,
while CO emissions dramatically increase with increasing the dosing
level of carbon multiwalled nanotubes. At the full load, the magnitude
of NOx and smoke emission for the neat diesel was 1282 ppm and
69HSU, whereas it was 910 ppm and 49HSU for the CMNT50 fuel,
respectively. The results also showed a significant enhancement in
brake thermal efficiency and heat release rate due to the influence of the
carbon multiwalled nanotubes addition in diesel blend.

The influence of injection parameters like injection pressure and injection duration on performance and emission of a common rail direct injection system assisted diesel engine has been evaluated using central composite design (CCD). The tests have been carried out on a four stroke, single cylinder DI diesel engine. The fuel injection system of the diesel engine used was the high pressure common rail direct injection system. From the experiments, it is observed that the brake thermal efficiency (BTE) is improved and fuel consumption reduced due to better atomization. It is also observed that carbon monoxide (CO), unburned hydrocarbons (HC) and smoke emissions are reduced and NOx emissions increased when increasing the injection pressures. This is due to injected fuel droplets find smaller as the injection pressure increases, which leads to improve atomization of the fuel.

— In this study, two factor central composite face centered design was employed to study and optimize the process variables on pilot injection strategy in common rail direct injection diesel engine. The effect of process variables such as pilot injection quantity (5-25%) and pilot injection angle (5-30º before main injection) is studied. The effect of pilot injection on NOx, noise emission and performance of a single cylinder direct injection diesel engine is investigated. By advancing the timing and quantity of pilot injection decreases the NOx and noise emissions. Pilot injection at advanced injection angles serves to decrease the NOx and noise while suppressing the increase of HC and fuel consumption. These effects due to the reduced amount of adhering fuel to the cylinder wall.

Experiments were conducted to determine engine performance, exhaust emissions and combustion characteristics of a single cylinder, common rail direct injection (CRDI) system assisted diesel engine using diesel with 25 percentage of zizipus jujube methyl ester blended fuel (ZJME25). Along with this ZJME25 aluminium oxide nanoparticles were added as additive in mass fractions of 25 ppm (AONP 25) and 50 ppm (AONP 50) with the help of a mechanical Homogenizer and an ultrasonicator. It was observed that aluminium oxide nanoparticles blended fuel exhibits a significant reduction in specific fuel consumption and exhaust emissions at all operating loads. At the full load, the magnitude of HC and smoke emission for the ZJME25 before the addition of aluminium oxide nanoparticles was 13.459 g/kW h and 79 HSU, whereas it was 8.599 g/kW h and 49 HSU for the AONP 50 blended ZJME25 fuel respectively. The results also showed a considerable enhancement in brake thermal efficiency and heat release rate due to the influence of aluminium oxide nanoparticles addition in biodiesel–diesel blend.

In this study, pine oil is used an alternative fuel for petrol in gasoline engine. Results compared the performance and emission characteristics of gasoline engine with the blend of sole fuel with pine oil. The investigation was carried out in the Tata nano engine with multipoint fuel injection (MPFI) system, twin cylinder water cooled gasoline engine. The investigations were carried out by the pine oil gasoline blends varying percentage of P10%, P20%, P30% and P40%. From the results it was observed that the brake thermal efficiency increased for P20% blend by 1.64% when compared to that of sole gasoline fuel. The CO, HC, are found decrease and increase in NOx emission with the P20% of pine oil blend compared to that of gasoline sole fuel. The CO, HC are decreased by 31%, 8% respectively for the P10 blend and 17% increases of NOx emission.

— This present study on biodiesel blends shows the performance, emission and combustion characteristics of the DI diesel engine, which is been run independently on direct diesel fuel, 20% blending of zizipus jujbe methyl ester (ZJME20), and 20% blending of mahua methyl ester (MME20) with diesel. In this study, the tested fuels were obtained by catalytic transesterification process. Based on the experimental results, MME20 is favorable for less HC, CO, and smoke density than diesel and ZJME20. Based on the brake thermal efficiency and specific fuel consumption, MME20 is better when compared with ZJME20. The result also showed momentous improvement in the heat releasing rate due to the better performance characteristic of MME20.

In this work, two oxygenated additives like methyl tert butyl ether (MTBE) and di-isopropyl ether (DIE) are identified for the experimental investigation by blending them to 5 ml with gasoline sole fuel. The performance and emission analysis were examined in twin cylinder SI engine with both additives blend with gasoline. The physical and chemical properties of the gasoline fuel and additives are tested through ASTM standards and reported. From the experimental results, it was found that brake thermal efficiency increased to 1-2% and emissions like HC and CO reduced to7-9% and 13-25%, respectively for addition of MTBE and DIE. NOx emission found increased in the both additive cases.

In this work, two oxygenated additives like Cyclohexylamine and n-butyl alcohol are identified for the experimental investigation by blending them to 5 ml with gasoline sole fuel. The performance and emission analysis were investigated in twin cylinder SI engine. The physical and chemical properties of the gasoline fuel with additives are tested through ASTM standards and reported. From the experimental results, it was found that brake thermal efficiency increased to 1-1.5% and NOx emission found increased in the both cases. Emissions like HC and CO reduced to 6-7% and 11-22%, respectively for addition of Cyclohexylamine and n-butyl alcohol.

In this paper, aluminium oxide nanoparticles (ANPs) were added to Mahua biodiesel blend (MME20) in different proportions to investigate the effects on a four stroke, single cylinder, common rail direct injection (CRDI) diesel engine. The ANPs were doped in different proportions with the Mahua biodiesel blend (MME20) using an ultrasonicator and a homogenizer with cetyl trimethyl ammonium bromide (CTAB) as the cationic surfactant. The experiments were conducted in a CRDI diesel engine at a constant speed of 1500 rpm using different ANP-blended biodiesel fuel (MME20 + ANP50 and MME20 + ANP100) and the results were compared with those of neat diesel and Mahua biodiesel blend (MME20). The experimental results exposed a substantial enhancement in the brake thermal efficiency and a marginal reduction in the harmful pollutants (such as CO, HC and smoke) for the nanoparticles blended biodiesel.

Over the last thirty years composite materials, plastics and ceramics have been the dominant emerging materials. The volume and number of applications of composite materials have grown steadily, penetrating and conquering new markets relentlessly. Modern composite materials constitute a significant proportion of the engineered materials market ranging from everyday products to sophisticated niche applications. While composites have already proven their worth as weight-saving materials, the current challenge is to make them cost effective. This review paper discuss about world wide review report on natural fibers and its applications. Also, this paper concentrates on biomaterials progress in the field of orthopaedics. An effort to utilize the advantages offered by renewable resources for the development of biocomposite materials based on bio epoxy resin and natural fibers such as Agave sisalana; Musa sepientum; Hibiscus sabdariffa and its application in bone grafting substitutes.