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Study on Indirect Tensile Strength of Plastic Waste Bituminous Concrete for Road Construction

Abstract

The rutting and cracking of pavements has become very common problem in India. Also the quantity of plastic waste has significantly increased in the recent year due to industrialization and population growth. Improper disposal of these plastic wastes has caused various environmental problems, hence the alternative use of waste plastic in bituminous concrete for road construction has been encouraged by the community. In the present study the Indirect Tensile Strength Test has been carried out on Marshall Samples confirming to ASTM D6931-12. Three different processes (dry process, wet process and combined process) of mixing of waste plastic were used during experimentation. It was found that the indirect tensile strength (ITS) and tensile strength ratio (TSR) of sample significantly increase up to 8%, 6% and 12% for dry process, wet process and combined process respectively for LDPE and HDPE type of waste plastic.

Open access
Barriers and opportunities in implementation of Lean Manufacturing tools in the ceramic industry

Abstract

The concept of lean management in an organization, improving products and processes using the Lean Manufacturing concept, is discussed in this paper. Striving for excellence is the key factor in maintaining competitiveness on the market. Only organizations able to adapt to changing environmental conditions faster than others achieve an advantage, and the management in line with the Lean Manufacturing philosophy is de facto change management. In this paper, important factors in the ceramic industry, which should be taken into account when implementing Lean Manufacturing are characterized. Important factors affecting the implementation of lean tools include, such as: the size of the enterprise, involvement of employees, knowledge about the Lean concept, technological factor, type and variety of the product line, as well as the specificity of the ceramic industry. The greatest opportunity associated with the implementation of Lean is to increase the competitiveness of the company obtained through: meeting the quality and economic expectations of customers. The greatest opportunity associated with implementation of the Lean is to increase competitiveness of the company obtained through: meeting the quality and economic expectations of their customers. Practice shows, however, that despite the simplicity of rules and tools, few organizations manage to achieve the level of excellence of the pioneer of this concept, the Japanese Toyota Corporation.

Open access
Classification of traffic signal system anomalies for environment tests of autonomous vehicles

Abstract

In the future there will be a lot of changes and development concerning autonomous transport that will affect all participants of transport. There are still difficulties in organizing transport, but with the introduction of autonomous vehicles more challenges can be expected. Recognizing and tracking horizontal and vertical signs can cause a difficulties for drivers and, later, for autonomous systems. Environmental conditions, deformity and quality affect the perception of signals. The correct recognition results in safe travelling for everyone on the roads. Traffic signs are designed for people that is why the recognition process is harder for the machines. However, nowadays some developers try to create a traffic sign that autonomous vehicles can use. Computer identification needs further development, as it is necessary to consider cases where traffic signs are deformed or not properly placed. In the following investigation, the advantages and disadvantages of the different perception methods and their possibilities were gathered. A methodology for the classification of horizontal and vertical traffic signs anomalies that may help in designing better testing and validation environments for traffic sign recognition systems in the future was also proposed.

Open access
The evaluation of wear of tungsten carbide dental bur

Abstract

Due to its durability, tungsten carbide has long been used as a material to produce dental burs. WC– Co burs are designed for smooth, efficient cutting and extended life. Dental burs are available in different sizes and shapes, for example round burs, pear and cylinder-shaped, egg-shaped, as well as there are various tapered ones, which enable an individual selection of the drill for the right treatment. Carbides can be used for standard crowns and bridges, for extensive surgical procedures and they should minimize damage to the existing teeth. The design of WC–Co dental bur reduces a patient’s discomfort because of the operating time and the fact that its liquidity is preserved. The head of the bur (the cutting edge) delivers optimum concentricity and strength. The shank is made from stainless steel allowing a bur to be autoclaved multiple times without the risk of corrosion. The main purpose of this study was to evaluate the wear of a tungsten carbide dental bur. The results of stereoscopy microscope and SEM/EDS analysis are presented.

Open access
Fatigue lifetime of 20MnV6 steel with holes manufactured by various methods

Abstract

In this paper, the authors publish their own experimental results of the examination of the different holes (milled, drilled and drilled + shot peened) on the fatigue lifetime of 20MnV6 steel. The experiments were carried out at low-frequency loading (f = 10 Hz, pulsating tension loading) in the region from N = 2×105 up to N = 2×106 cycles. The best fatigue properties were obtained in the parts with drilled + shot peened holes.

Open access
Influence of modifcation on the refinement of primary silicon crystals in hypereutectic silumin AlSi21CuNi

Abstract

On the paper the influence of modifying micro additives on the refinement of primary silicon crystals in the hypereutectic AlSi21CuNi piston silumin have been examined. As the modifiers there were used micro additives of Phosphorus in the form of AlCu19P1.4 and CuP12 pre-alloys, sulfur in the form of CuS and iron in the powdered form. The modifying micro additives were used separately and together. Micro additions of iron were used together with phosphorus. Sulfur micro addition provided the fragmentation of the primary silicon crystals, but not as effective as the phosphorus micro additive. The best effect of fragmentation of the primary silicon crystals was ensured by the combined addition of phosphorus in the form of AlCu19P1,4 pre alloy with a micro additive of powdered iron which reduced the average size of the primary silicon crystals from 114 μm to 20 μm.

Open access
Obtaining of biomorphic composites based on carbon materials

Abstract

Aim of this paper is to present the properties of carbon preforms for the production of biomorphic composites. Carbon samples were obtained through pyrolysis of paulownia wood, replicating the microstructure of the cellulosic precursor. Many characterization methods such as Raman Spectroscopy, light microscopy, hardness tests and pore size analyzer detection were used to investigate the microstructure of the product as well as the pore size of carbon samples. Obtained results showed that the parts of early or late wood template play an important role in the pore size, specific surface area and pore volume of the product. This review aims to be a comprehensive description of the development of carbon chars: from wood templates and their microstructure to potential applications of biomorphic materials.

Open access
An offline path planning method for autonomous vehicles

Abstract

Driving a road vehicle is a very complex task in terms of controlling it, substituting a human driver with a computer is a real challenge also from the technical side. An important step in vehicle controlling is when the vehicle plans its own trajectory. The input of the trajectory planning are the purpose of the passengers and the environment of the vehicle. The trajectory planning process has several parts, for instance, the geometry of the path-curve or the speed during the way. Furthermore, a traffic situation can also determine many other parameters in the planning process.

This paper presents a basic approach for trajectory design. To reach the aim a map will be given as a binary 2204 x 1294 size matrix where the roads will be defined by ones, the obstacles will be defined by zeros. The aim is to make an algorithm which can find the shortest and a suitable way for vehicles between the start and the target point. The vehicle speed will be slow enough to ignore the dynamical properties of the vehicle. The research is one of the first steps to realize automated parking features in a self-drive car.

Open access
Quality control of a metallic dental bur with a diamond coating

Abstract

During operation, sterilization and disinfection, the surface working part of dental burs deteriorates. In this study a commercial metallic dental bur with extra coarse gradation (177-250 μ of ceramic embankment), made of a stainless steel were covered with a nickel-diamond composite was examined. The working part of the tool is round-end taper shaped and is intended for crown and bridge preparation. Analysis of microstructure was carried out using Jeol JSM-6610 LV scanning electron microscope with EDX analyzer. After 3 months of operation, the bur can be used for further work in the dental surgery.

Open access
Six Sigma as a method of improving the quality of service process

Abstract

The objective of the analysis conducted and described in this paper has been to present the practical application of the Six Sigma method based on the DMAIC cycle in improving the quality of the service process. The first part of the article contains the theoretical framework of six sigma and the issue of using its tools in the aspect of services. Afterwards, there has been calculated the initial sigma value which indicated the need for improvement. Measurement phase has been developed by the value stream mapping, process FMEA and customer survey which results have been analyzed in Pareto chart and fishbone diagram. Improve phase includes the Impact&Effort Matrix and target sigma level that can be achieved as a result of failures reducing and service quality improvement.

Open access