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Abstract

Most of the people living in developing or less developed countries have limited earning to provide somehow their basic needs and usual staff. Carrying goods is a regular task in life and several products have been invented to minimize efforts in this purpose. However, the price and features of most available products are out of the reach for the people of limited earnings. Stair climbing cart is very useful for those houses where a lift is not available. In this research, a modified mechanical design with eight wheels providing pause-rest feature has been represented with the equations of pulling force, constraints of stair dimensions and climbing mechanism. The ‘House of Quality Diagram ‘(QFD)’ has been added to accomplish the vision of further market research and customer satisfaction. The factor of safety and different types of stress have been determined for different types of loads and conditions. In addition, the details of the material with dimension, design and feasibility analysis have led this research to uniqueness.

Abstract

The aim of this study was to investigate the usage of Dynamic Image Analysis for determination of size, shape and distribution of granules of microcrystalline cellulose, created by high shear granulation. A series of experiments was carried out to analyse the effect of process parameters on a created granule morphology. The amount of the granulation liquid and speed of the impeller have a significant effect on the median size granule value, the sphericity, the granule distribution width, but also on the granulation process yield.

Abstract

Parabens are synthetic preservatives that are used on a large scale in the cosmetics, pharmaceutical and food industries. Their task is primarily to prolong the shelf life of selected products – cosmetics, medicines or food – by maintaining their microbiological purity. Parabens protect products against deterioration and microorganisms, extending their durability by up to several months without interfering with their composition and operation. Parabens do not change the aroma, taste, density or other characteristics of cosmetic or food products. However parabens, which occur in most cosmetics with a creamy or liquid formula (face creams, body lotions, foundation, tonics, lipsticks, deodorants, perfumes), are becoming increasingly worse because of the prolonged list of side effects that they may cause. The presence of intact paraben esters in human body tissues has now been confirmed by independent measurements in human urine, and the ability of parabens to penetrate human skin intact without breakdown by esterases and to be absorbed systemically has been demonstrated through not only in vitro studies but also in vivo investigation using healthy human subjects.

Abstract

The melting conditions of the electrode wires and the structure of coatings, obtained by the electric arc spraying method depending on the pressure of the spraying air flow, are analysed in the current paper. The effect of air pressure on the spraying angle of the flow of melted metal droplets is demonstrated. It is established that due to the decrease in this spraying angle, the temperature of the droplets increases. In addition, high-speed airflow is more easily captured by smaller molten metal droplets and during the contact with the substrate surface their deformations were more strongly. Due to such phenomenon, the porosity of the coatings was reduced and the number of lamellae, welded to each other, increased. With the increasing pressure of the air flow, the thicknesses of the lamellae were decreased, however, the amount of the oxide phase in the coatings has increased. As a result, the hardness, wear resistance and cohesive strength of the coatings, obtained at a higher pressure of the air flow, have increased, and the level of residual stresses of the first kind in them decreased.

Abstract

In this paper a new approach to the consistent identification of the deformation pattern vital for the precise determination of the plastic limit load of a cylindrical shell from MNA when using modified Southwell (MS) and Tangent Stiffness (TS) plots is presented. It is proposed that the formalised assessment of the plastic collapse load can be done by the application of the relation between the load factor increment ΔrR and the arc length s – for an identification of achievement of the complete plastic collapse mechanism from MNA, and then the MS or TS plot for the displacement pattern that corresponds to the identified plastic mechanism.

Abstract

This paper shows an analysis of the free vibration of functionally graded simply supported nanoplate. The nonlocal four variables shear deformation plate theory is used to predict the free vibration frequencies of functionally graded nanoplate simply supported using non-local elasticity theory with the introduction of small-scale effects. The effect of the material properties, thickness-length ratio, aspect ratio, the exponent of the power law, the vibration mode is presented, the current solutions are compared to those obtained by other researchers. Equilibrium equations are obtained using the virtual displacements principle. P-FGM Power law is used to have a distribution of material properties that vary across the thickness. The results are in good agreement with those of the literature.

Abstract

The PMS-EDDG is an effective hybrid process to beat the problems identified in machining of Inconel 600 through the conventional machining process. This hybrid-machining-process is a combination of SDG and Powder Mixed-EDM process. Modeling, comparative investigation, determination of optimal setting of process factors, and various surface developments in S-EDDG of Inconel 600 with chromium and absence of chromium-powder blended dielectric fluid (DF) have been narrated in this research work. One set of 31 experiments with chromium-powder and another set of 31 experiments without chromium-powder mixed DF was conducted on this set-up in accordance with the C-C-R-D plan of experimentation. The developed models through RSM support to investigate the behavior of input process-factors over the responses. The input factors in this research work are ampere-current (I), pulse-on-time (Ton), wheel speed (WS), and duty cycle (DC). The MRR and Ra are the output-responses in this machining process. The optimum setting of process-parameters is computed through the integrated Grey-Taguchi based WPCA-approach. The confirmation experiment is conducted on this set-up at the optimum-condition and its results display the agreeable matching among the actual and predicted values. The WMPI is improved by 0.414. The SEM investigation has been conducted at the optimum-condition on the produced machined-surfaces and on the produced white recast-layer thickness.

Abstract

The paper deals with the influence of selected component of synthesis gas on internal parameters of combustion engine that is planned to be used in micro-cogeneration unit. The aim is to better understand the mechanism of combustion of carbon monoxide mixed with methane and as a follow-up to optimize the operation of the Lombardini LGW 702 engine on change of fuel composition. Generally, an increasing proportion of carbon monoxide in methane mixture leads to a decrease in engine performance (mean indicated pressure) and the hourly fuel consumption in each of the operating modes of the engine increases. With growing proportion of CO in mixture with CH4, the maximum pressure in the cylinder increases together with pressure rise rate up to approximately 10 % vol. of CH4. With further increasing proportion of CH4, there is a significant decrease of the before-mentioned engine parameters. The optimum ignition angle for pure methane, or carbon monoxide, does not change significantly and it is about 27° CA BTDC.

Abstract

Fiction Stir welding (FSW) a unique type of metal joining process in solid state, where the heat generation takes place due to the friction action between the rotating tool and the work piece. It is generally used to join all series of Aluminum alloys with good strength and other metallic alloys finds difficult to weld through regular fusion welding techniques. The metal joining takes place in the solid state as the metal to be welded reaches about 80% to 90% of its melting temperature. The joining of metals in friction stir welding does not require any filler metals all classes of Aluminium alloys can be joined and in some desirable cases dissimilar metal compositions and Aluminiun metals composites can be joined satisfactorily. Joining of dissimilar metals has become a trend in the industries like aerospace, automotive chemical etc. as the helps in reducing the cost incurred by eliminating the costly materials. In the present study an experimental investigations are made to study the heat transfer behavior by determining the temperature distribution in AA5052-AA6061 plates during the Friction Stir welding. A three dimensional transient analysis is made by using ANSYS finite element analysis software. Thermocouples are placed at the suitable locations and the same point the temperature readings were taken from the simulation results. The experimental data is compared with the numerically simulated results. The numerical simulations results obtained are in better agreement with the experimental data obtained.

Abstract

Disability can cover various areas of people’s activities, but it is primarily associated with difficulties that relate to independent movement. The possibility of free movement is one of the basic human rights. People with disabilities who cannot get to work and take employment, despite a desire to do so, assimilate with the rest of society to a worse extent, do not have the means to support themselves and do not earn national income. From this point of view, programs and activities aimed at maximising mobility and access to various types of places for people with disabilities, including those in public space, are very important. These types of places include paid parking zones in cities. Their location in city centres provides access to most offices. Due to the fact that they are located in public space, municipalities and city authorities have an impact on their management and on establishing the principles of their functioning. A very important element of this management is determining the rules for providing parking spaces in paid parking zones, particularly with regard to the amount of parking fees for disabled people. The article provides an analysis of the management of the provision of disabled parking spaces in relation to paid parking zones in all voivodeship cities in Poland.