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Abstract

Integrating electric vehicles in a supply chain and distribution is a viable option when special conditions such as short distance road distribution and environmental considerations as well as small amounts of goods enabling delivery with delivery vans are met. In this paper, possibility of investment in electric vehicles for distribution of local food will be examined and analysed. Safety concerns in electric vehicles will also be addressed and accident consequences and vehicle safety will be analysed and compared with conventional vehicles that use internal combustion engines.

Abstract

Customers and their perception towards service are considered as a determinant of service failure, and so, service failure and its prevention must be looked into from the perspective of the customers. This paper presents a customer-centric service failure prevention framework, which aims to provide a holistic way of service failure prevention by integrating service delivery assessment and failure analysis from a customer perspective, encompassing failure identification, assessment and prioritization of failures as a basis for corrective actions. Customer journey, service clues, and customer oriented-FMEA are employed to develop the proposed framework. The approach was applied to an enrolment process showing that using customer journey assists in determining customer processes, needs, wants and touch points in the service, and when used together with service clues further facilitates systematic and effective unveiling of potential failures that are important to customers. Assessment of failures and its prioritization with customer perspective leads to better prioritization that is reflective of the voice of customers. The case study shows that higher risk is imposed by actions emanating from the employees, reinforcing further that service failures not only concern functionality of the service but equally important also are the encounter of customers with service employees and the environment.

Abstract

Automatic detection of objects is a part of visual systems supporting a quality control system of a manufacturing process. The paper concerns the influence of the resolution of images and the size of detected objects in pixels on measurements results. Test images of the objects of a known size were generated. The values of the perimeter of the objects were compared to the obtained values of measurements on the images with degraded resolution. The process of the degradation of the references images by successive downsizing the resolution, detection and measurements were performed applying automatic algorithm. The analysis of obtained results showed that the size of the analysed objects on the digital images plays an important role in reliability and accuracy of the measurement. The author concludes that, in order to avoid a bias in measurement caused by insufficient object resolution, the minimal acceptable size of objects on digital images in pixels should be recommended.

Abstract

Temperature is considered a complicated external factor of the susceptibility of stainless steels to the pitting. This paper deals with the corrosion behaviour of AISI 316Ti stainless steel in temperature range 22 - 80°C in aggressive chloride environments (3 and 5% FeCl3 solutions). The corrosion resistance of tested steel is evaluated on the base of results of exposure immersion tests and cyclic potentiodynamic tests. According to the obtained results the resistance of AISI 316Ti to the pitting is markedly affected by temperature changes in the range 22 – 80°C. Intensity of corrosion attack increases with the rise of Cl concentration. Gentle changes of temperature and Cl concentration cause significant differences in character of local damage. The appearance of pitted surfaces changes with the rise of the temperature (a density of pitting increases, a size of pits decreases). The strongest change in appearance is observed between 40 and 50ºC.

Abstract

The article deals with a reduction of friction coefficient of bearing steel 100Cr6. Reduction of friction was achieved by means of a CarbonX DLC coating. The coating exhibited excellent friction and mechanical properties. This coating was applied to samples made of 100Cr6 bearing steel. The friction results of the CarbonX coating were compared to the friction results of the 100Cr6 bearing steel. Reducing the friction of 100Cr6 bearing steel resulted in reduced wear and increase lifetime. The friction process of the samples will take place in an environment without lubrication. The aim of the article is to verify the behaviour of the DLC coating without the presence of lubricant in the friction node. The achieved results are to be interpreted in the conclusion of article.

Abstract

The lack of a common methodology on compaction theory stimulates developers of road construction equipment to create various approximate methods for their calculation, the number of which, at the present time, is comparable with the nomenclature of the proposed designs of rollers. The article presents the analysis of the deformable shell behavior of a road roller, and the compacted material under its compacting roller, in a situation when a rigid circular shell of the roller is replaced by a forcefully deformable elliptical shape, which, unlike the circular design, allows variation, adjustment and optimization of the road roller impact on the material to be compacted.

Abstract

The paper contains an overview of the history of engineering education in the United States. It also explains the differences between engineering and engineering technology from an historical perspective. The similarities and differences between those two programs are also being addressed. The article also explains the concept of the project-driven approach in teaching engineering technology courses. The procedure to secure and administer funding for the projects is also addressed. The paper also includes some practical guidelines for implementing a project-based approach.

Abstract

Additive manufacturing has recently expanded its potential with the development of selective laser melting (SLM) of metallic powders. This study investigates the relation between the mechanical properties and the microstructure of Ti6Al4V alloy produced by SLM followed by a hot isostatic pressing (HIP) treatment. HIP treatment minimizes the detrimental influence of material defects. Tensile specimens produced with reference to specific building axes were prepared using a Renishaw A250 system. It has been found that the tensile strength and elongation depend on specimen building direction. Microstructural and textural characterizations were carried out to identify the source of differences.

Abstract

The windshield defrost system, in general, is a vehicle safety feature. Thus, its restricted by variety of directives. However, the OMEs’ benchmark targets could be even more demanding as the deicing process is in addition also part of passengers comfort. From vehicle design point of view the wind-shield defrost system is typically connected to HVAC unit (Heating, Ventilation and Air Conditioning). In the technical solution the windshield is heated via hot air convection. Nevertheless, other methods are becoming more and more popular, like directly heated glass by hot wire ohmic heating (heated glasses). The defrost CFD model should predict the ice layer thickness in time and space and in environmental conditions defined according to appropriate directives and technical solution. The accurate and fast modelling technique is essential part of a vehicle development, especially nowadays, where the optimization techniques area widely used and requires hundreds of simulations runs. Modelling requests are even increasing with modern pure electric vehicles (EVs), were the thermal and energy management is more demanding compared to the classical internal combustion engine (ICE) vehicles. The aim of the work is to verify possibility to model the ice layer thickness with simplified approach, which could be beneficial from computational time burden.

Abstract

The sieves’ manufacturers that want to be competitive at the market must have the implemented quality control system. Different methods, based on taking the sample, which is a representative of the total quantity of the forming sieves production, are applied for evaluation of the sieve’s conformity. The basic characteristics of this type of the quality function are control, measuring and testing of the forming sieves’ properties at the end of the manufacturing process. The objective is to detect and separate the products that deviate from the set criteria, to remain in the factory, then to be repaired if possible or discarded in the opposite case and thus to prevent delivery of the defective sieves to the paper manufacturers.