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Overview of the main methods of service quality analysis

Abstract

Everyone, every day or almost every day, uses various type of services, without being even aware of it. They could have been both intangible and material services. Customers want to receive services of the highest quality, and service providers are looking for solutions to meet their requirements. They can analyze the quality of their services to indicate the strengths and weaknesses of these services to know what needs to be improved and what can be omitted. In the literature on the quality engineering, many methods that can be used in such a situation are described. In most cases, these methods are based on the differences between customers’ expectations for the service and the perception of the service which they received. In case of most of these method, there is a need of information from customers about research service, which means that they are involved in this process. In the paper five methods of quality service analysis, which are the most often used by service enterprises, were briefly characterizes to help readers to choose the most accurate one for them.

Open access
Plastic production machinery – the evaluation of effectiveness

Abstract

In this paper TPM and PAMCO coefficients were shortly characterised. On the basis of TPM coefficients its effectiveness was estimated. Thanks to using time and PAMCO coefficients, the utilization of working time machines was researched. Moreover, there a correlation between TPM coefficient and the quality level was examined. A histogram was drawn up in order to illustrate the distribution. The obtained results allowed to evaluate the effectiveness of the machine. The period of research embraced fifty-two weeks (1 year) and the object of the analysis is the injection moulding machine.

Open access
Prediction of fatal accidents in Indian factories based on ARIMA

Abstract

The inherent benefits of an accident prevention program are generally known only after an accident has occurred. The purpose of implementation of the program is to minimize the number of accidents and cost of damages. Allocation of resources to implement accident prevention program is vital because it is difficult to estimate the extent of damage caused by an accident. Accurate fatal accident predictions can provide a meaningful data that can be used to implement accident prevention program in order to minimize the cost of accidents. This paper forecast the fatal accidents of factories in India by using Auto-Regressive Integrating Moving Average Method (ARIMA) model. Accident data for the available period 1980 to 2013 was collected from the Labour bureau, Government of India to analyze the long term forecasts. Different diagnostic tests are applied in order to check the adequacy of the fitted models. The results show that ARIMA (0, 0, 1) is suitable model for prediction of fatal injuries. The number of fatal accidents is forecasted for the period 2014 to 2019. These results suggest that the policy makers and the Indian labour ministry must focus attention toward increasing fatal accidents and try to find out the reasons. It is also an opportunity for the policy makers to develop policies which may help in minimizing the number fatal accidents.

Open access
The process approach to service quality management

Abstract

In this paper a model of service quality management based on the process approach has been presented. The first part of the article contains the theoretical framework of service quality and the process approach in management. Next, quality of service process has been presented in reference to a process-based definition in quoted literature. Finally, the outcomes of a customer questionnaire concerning the validity of particular quality attributes has been presented. The collected data in relation to service process quality stages have enabled the development of a of service quality model for process management.

Open access
The use of QFD method advantages and limitation

Abstract

The following paper concentrates on some problems resulting from the use of Quality Function Deployment method in industrial enterprises. It is not an easy task although the method itself has many advantages. The aim of the paper is to analyse basic international literature as well as the main advantages and limitations of the Quality Function Deployment

Open access
Corrosion and Wear Analysis in Marine Transport Constructions

Abstract

Corrosion is one of the most common naturally occurring processes studied by thermodynamics, which includes oxidation process, metal disruption, and its chemical and electrochemical effects under environmental influence. Corrosion of metal and equipment accounts for a considerable proportion of total corrosion losses, thus providing the impetus for further investigation and developments related to corrosion protection in order to provide transport systems and industry with corrosion preventive materials and tools.

Open access
ADS-B Satellite Communication Channel Based on IEEE 802.16 Standard

Abstract

Original models of “Aircraft-Satellite-Ground Station” communication channel based on IEEE 802.16 standard were built by using MATLAB Simulink. The influence of aircraft transmitter nonlinearity for different types of fading in the channel (Rayleigh and Rician) was studied and the possibility of correcting nonlinearity by using pre-distortion was revealed. The impact of space-time diversity (MISO 2 × 1) for different types of fading in channels was investigated. The effect of the Doppler frequency shift on the operation of communication channels was analyzed.

Open access
Aerodynamic Research of the Experimental Prototype of the Variable Geometry Wind Turbine

Abstract

The aim of this research is to develop a vertical rotation axis variable geometry wind turbine (WT). The experimental prototype is being manufactured with the help of CAM (Computer-aided manufacturing) technologies – computer-based preparation of the product manufacturing process. The Institute of Aeronautics of Riga Technical University is using CNC (Computer Numerical Control) machines for manufacturing the innovative WT and its components. The aerodynamic research has been done in T-4 wind tunnel at an air flow rate from 5 m/s to 30 m/s. The power increase of the variable geometry WT is a topical issue. Installation of such WTs in wind farms is possible and is subject to further research.

Open access
Applying “Spark Plasma Sintering” Technology to Enhance the Resistance to Contact Fatigue of Sintered Steel Based on Astaloy CRL

Abstract

The article deals with the effect of porosity on the contact fatigue of sintered material type Astaloy CrL with 0.3 and 0.4% C. Sets of samples were used with densities beginning from the value of 7000 kg.m−3 to the value of almost 7859 kg.m−3 which represents almost zero porosity (compact material). It has been found out that the increase of compacting pressure applied simultaneously with temperature results in the reduction of porosity from the value of 9.10% to 0.0005% and increase in hardness from 145 to 193 HV10, depending on the carbon content. Logically there is also an increase in the fatigue life by the contact fatigue tests for the value of 50×106 cycles from the value of 900 MPa to 1150 MPa for samples with 0.3% of C and from 900 MPa to 1300 MPa for samples with 0.4% C. These investigations were also carried out in the past, but to achieve the reduction of porosity, different technonologies were used at each level such as double pressing, hot pressing, saturation, hot forging, etc. In this case, the single technology of “spark plasma sintering” making use of compacting at high temperatures is capable to continuously reduce porosity to zero.

Open access
Comparison of Different Stall Conditions in Axial Flow Compressor Using Analytic Wavelet Transform

Abstract

The rotating stall inception data analysis using Analytic Wavelet Transform (AWT) in a low-speed axial compressor was presented in the authors’ previous studies [1], [2]. These studies focused on the detection of instability inception in an axial flow compressor when it enters into the instability regime due to the modal type of stall perturbation. In this paper, the effectiveness of AWT is further studied by applying it under different testing conditions. In order to examine the results of AWT on highly sampled data, at first, the stall data were acquired at a high sampling frequency and the results were compared with the conventional filtered signals. Secondly, the AWT analysis of stall data was carried out for the condition when compressor experienced a spike type rotating stall disturbance. The stall inception information obtained from the AWT analysis was then compared with the commonly used stall detection techniques. The results show that AWT is equally beneficial for the diagnostic of compressor instability regardless of the data sampling rate and represents an outstanding ability to detect stall disturbance irrespective of the type of stall precursor, i.e. the modal wave or spike.

Open access