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Development and Characterization of Sisal Fiber Reinforced Polypropylene Composite Materials
348-358Views:428In most of the developing countries, plastic polypropylene is not fully recycled and converted in-to use after it is once used. Sisal fiber is also widely available in different developing countries like Ethiopia. Adding this two materials and developing automotive interior part was taken as a primary motive for it reduces cost and is environmentally friendly. Thus, the main purpose of this research is to develop composite material from natural fibre (sisal fiber) reinforced with recycled plastic waste (polypropylene) for interior automobile accessories specifically for internal door trim panel application. This research examines effect of fiber length, fiber loading and chemical treatment of fiber on the physical and chemical properties of the sisal fiber reinforced polypropylene (SFRPP) composite material. The waste polypropylene and the treated and untreated sisal fiber with variable length and weight ratio (fiber/matrix ratio) were mixed. Flammability of sisal fiber reinforced Polypropylene (SFRPP) composites material was examined by a horizontal burning test according to ASTM D635 and chemical resistance of the sisal fibre reinforced PP composites was studied using ASTM D543 testing method. The result on the flammability test shows that treated fiber has lower burning rate than untreated fiber and decreases with increase in fiber length and fiber loading. The resistance of the composites to water has increased as the fiber length increases and decreased as the fiber loading increase. Generally, SFRPP composite is found to have better resistance to water than NaOH and H2SO4 and treating the fiber has brought considerable improvement on chemical resistance of the composite. Fiber loading and fiber length has positive and negative effect on the flammability of the SFRPP composite respectively.
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Parameter Estimation of Drag Coefficient and Rolling Resistance of Vehicles Based on GPS Speed Data
109-115Views:169In this paper, a parameter estimation method of the model-based design approach is applied to estimate the drag coefficient and the rolling resistance coefficient of a vehicle. In fact, a constant-force parameter (c_const) and a velocity-square-force parameter (c_square) are in the vehicle model, and these result in the sum force applied along the translational DOF that models the vehicle. It is only an assumption that the constant force is the rolling resistance and the force proportional to the square of the velocity is the drag force of the air. Only GPS speed data is used for the estimation process. The conclusion is that parameter estimation is a good alternative when expensive measurement devices are not available to measure the force losses separately and directly.
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Properties of Cellulose Sheets Modified with Potassium-Humate and Copper (II)-Sulfate
276-285Views:109Throughout our research we have made potassium-humate from brown coal of Dudar. With potassiumhumate and copper(II)-sulfate we made test sheets of linter cellulose fibers. The surface energy, surface wettability, CIE Lab color-coordinates changing, bending resistance and tensile strength of the produced test sheets has been examined. There was no big difference in the different samples during surface energy and wettability testing. Examination of mechanical properties suggests that potassium-humate content increases bending resistance of the test sheets. The bending resistance of samples increased by 32%, 100% and 336% compared to the control test sheets while adding potassium-humate.
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The Role of Employee Participation and Resistance in the Success of Change Management
22-30Views:262Successful change in the lives of organizations has played a particularly important role in the recent turbulently changing decades, and leadership-follower relationships need to be addressed in order to maintain performance. Participation should be ensured for members of the organization and emerging resistance should be addressed. The subject of my research was to examine whether the assessment of the success of change is influenced by the provision of opportunities for employees to make suggestions and their opposition to change. By performing chi-square tests, I came to the conclusion that if the opinion of the worker is heard, they are more likely to judge the change to be successful, however, the manager is not affected by the involvement of the employees in this. However, there is a correlation between employees' resentment to change and the success of change, both from the employee and managerial side, change is more unsuccessful if resentment develops. Based on the results, both factors are important. It is worth drawing the attention of managers to the need to ensure participation, as failure to do so can lead to dissatisfaction among employees, which can also have a negative impact on the success of the organization.
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Investigation of the Resistance Force Acting on a Sailing Craft in the Case of a Change of Draft Caused by a Change of Powertrain Using Numerical CFD Simulations
30-35Views:229Nowdays In the case of recreational craft, interfering with motor drive solutions is a common workflow due to increasingly strict rules for environmental reasons. When switching from an internal combustion engine to an electric engine, the change in draft varies from boat to boat, but it can be said in all cases that as the mass changes, so does the draft. Because of this, the magnitude of the resistance force acting on the ship also varies. In this paper, we examine, through a specific example, the benefits of a change in dive caused by weight gain at different travel speeds.
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Analysis of Abrasion of Hot Metal Powder Spray Coated Layer
342-346Views:193By the application of the tradicional overhead welding and the different powder coating technologies results a new surface with improved abrasion resistance, we can optimize the dimensions of the part or we can rebuild some surface as a kind of repairing technology. By application of this technology we can avoid the replacement of the total expensive parts of the structure. Opposite to the tradicional overhead welding in this case there will be diffusion connection between the raw material and the surface coating, this connection type shows several positive properites. Our goal is to investigate the abrasion resistance of the coating. In this article we would like to introduce our results of the abrasion test by apllication of different powder coatings.
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Effects of TIG Reheating on Duplex Stainless Steel Weld Microstructure
295-302Views:164Duplex stainless steels (DSS) gaining their excellent mechanical properties and corrosion resistance due to their austenitic-ferritic microstructure, ideally in the same amount. However, to keep this ideal phase ratio during arc welding is very difficult. Generally, the arc welding processes will result in more ferritic microstructure in the weld metal and in the heat affected zone, due to the rapid cooling. The ferritic microstructure can cause chromiumnitride precipitation, because the nitrogen solubility in ferrite phase is very low below 700 °C. These chromiumnitride precipitations can cause loss of corrosion resistance and mechanical properties. However, during subsequent reheating, the chromium-nitrides can dissolve and act as a secondary austenite nucleation site in the ferritic microstructure. In our research we welded DSS specimen autogenously, with tungsten inert gas welding using pure argon and 94 % argon + 6 % nitrogen as shielding gasses. In the first case the sub-sequent solid-state reheating caused 20 % increase in the austenite fraction of the weld metal but with the use of mixed shielding gas only 5 % increase.
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The Effects of Quenching and Tempering Treatment on the Hardness and Microstructures of a Cold Work Steel
286-294Views:276The X153CrMoV12 ledeburitic chromium steel characteristically has high abrasive wear resistance, due to their high carbon and high chromium contents with a large volume of carbides in the microstructure. This steel quality has high compression strength, excellent deep hardenability and toughness properties, dimensional stability during heat treatment, high resistance to softening at elevated temperatures. The higher hardness of cryogenic treated samples in comparison with conventional quenched samples mean lower quantity of retained austenite as at samples quenched to room temperature and tempered in similar condition. In the microstructure of samples were observed that the primary carbide did not dissolve at 1070°C and their net structure have not been changed during to heat treatment. During to tempering at high temperature the primary carbides have become more and more rounded. After low tempering temperature in martensite were observed some small rounded carbides also, increasing the tempering temperature the quantity of finely dispersed carbides increased, which result higher hardness. The important issues in heat treatment of this steels are the reduction or elimination of retained austenite due to cryogenic treatment.
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The Effect of annealing temperature on corrosion resistance and microstructure of Zr-Sn-Nb-Fe alloy
420-424Views:126The Ti-2Al-2.5Zr titanium alloy plate in beta phase water quench at different times of the reentry after annealing is implemented while primary phase number and size distribution of samples are obtained. This research is carried out on corrosion behavior in 3.5% [mass fraction] NaCl solution. Experimental study showed that after the beta phase water quenching Ti-2Al-2.5Zr titanium alloyed after 500 oC annealing when partial recrystallization happened. There seems to be lots of tiny dispersion in the alloy that was annealed with its samples of six-party [HCP] structure of Ti, Zr, Al phase 2 with the dimension below 100 nm. Reaching 500 oC when the rate of annealing at a primary phase of the sample at 550 oC is low 90% of the primary phase is less than 100 nm. The changing of the rule of present decreasing also triggers little difference overall. Precipitation in the process of annealing Zr [Nb,Fe,Cr] 2is less that proves to be good for corrosion resistance.
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Development of a Low-cost Pressure Sensor
33-38Views:236In this paper development of a pressure sensor has been discussed. The main benefit of this sensor is relatively cheap compared to commercially available ones. The unit contains a beam type load cell and a pneumatic cylinder. The load cell has 4 strain gauges in Wheatstone bridge configuration in order to convert the change of resistance into measurable voltage. The system is well applicable in numerous circumstances, where digital pressure signal is necessary for control or data acquisition.
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Building’s Constructions and Structures. Part II. Changes of Structures in Supporting Structures of Buildings
79-99Views:132In the Part II. we deal with the changes of structures in supporting structures of buildings. The changes of the structure we will connected with new materials or new approach. We deal with two problems. First is the formations and change of the vault. The second is the change of the supporting structure of buildings in case of using new materials with bending or only stretching resistance.
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Calculations of Performance Losses for Automobile Vehicles
210-218Views:221Vehicle-energetic-models are used to analyze the performances and when a comprehensive structure is established even optimization could be done. For these kinds of models, the losses of the vehicles have to be known. These losses could significantly effect of the vehicle fuel consumption. From these losses the rolling resistance, drive elements and aerodynamic drag are discussed. This paper reviews some of the literatures that describes the calculation methods and gives us some idea about the degree of their value. Our further goals are to have an UpToDate loss coefficient dataset and calculation methods for further vehicle-energetic modelling.
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A study of pressure-sinkage relationship used in a tyre-terrain interaction
186-199Views:170The vehicle applies a normal load to the terrain, which causes sinkage and motion resistance. To forecast the normal pressure distribution on the interface of a vehicle–terrain and the tractive performance of a vehicle, the response of the terrain to normal load (which is characterized by pressure–sinkage relationship equations) must be measured. This paper presents the common conventional pressure sinkage models used in terramechanic and the modification that happened to this models. In addition the features of the new models.
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A Slurry-Pot Abrasive Wear Test Device for Several Composite Materials
437-444Views:107To choose the proper material for agricultural machinery we tested several materials with abrasive cloth on the pin-on-plate test device. After having the pre-results, we launched more complex abrasive testing (slurry-pot) simulating more realistic mode with soils to investigate the abrasive wear mechanism and resistance of the selected up-to-date polymeric structural materials. for this, we developed a modified slurry-pot test machine that ensures the comparability of the materials over a wide range of conditions. Through this device, several parameters could be controlled like speed, the soil particle’s hit angle on the tested surface.
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Measuring the Dynamic Characteristics of Electric Motors
359-364Views:133In our previous publications [1, 2], we described our vehicle dynamics simulation program which was developed in MATLAB environment. We also discussed its use for optimizing the technical parameters of electric driven vehicles. We detailed the model and simulation of the series wound DC motor which is part of the program. Besides, we described the experimental procedure by which we can determine the electromagnetic characteristics of the motor from the input parameters of the simulation program. In the present publication we deal with the determination of the dynamic characteristics of the motor (the moment of inertia of the rotor, bearing and brush resistance torques) experimentally. Knowing the above mentioned electromagnetic and dynamic characteristics, we can carry out the simulation of the motor and the results of the simulation can be compared to the results of the test measurements.
