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Acta polytechnica HungaricaVolume 14, Issue No. 8. (2017.)

Tartalom

  • Erika Seres-Huszárik ,
    László Józsa ,
    Zsuzsanna Tóth :

    Abstract: Factors affecting the success of business relationships for a long while have been in the focus of those specialists and professionals who are interested in the topic over the last two decades have caused significant changes in everyday life of participants in the economy. Over the past decades the concept of relationship marketing has become well-known and widely spread in business life. It is a well-known fact that the cost of acquiring a new customer is much higher than the cost of keeping an existing one. Participants of the economy define relationship marketing as a strategy to achieve customer loyalty. During the initial phase of the relationship, the company aims to establish a strong relationship with the customer, to win indifferent customers and make them loyal. Based on the above-mentioned factors, we found it important to asses the factors affecting the agency-client relationship. Based on several empirical studies, in our research we tried to answer the question whether it can be stated on the basis of the unanimous opinion of the participants of the Slovak advertising market that during the development of business relationships interpersonal relationships play the most important role ((hypothesis testing). Results of our research will help us understand the development of the agency-client relationships, and provide practical results for the advertising industry.

    Keywords: advertising agency; client; relationship

  • Lőrinc Márton ,
    Zoltán Szántó ,
    Tamás Haidegger ,
    Péter Galambos ,
    József Kövecses :

    Abstract: This study presents a teleoperation system for remote control of mobile manipulators over the Internet. A bilateral control algorithm is proposed that can assure both stability and proper force reflection in the presence of non-constant delay in the communication channels between the master and the slave. The control approach in this paper is based on the time domain passivity concept and proposes a modified passivity controller to assure enhanced transparency with bounded control actions in the presence of time-varying communication delay. Transatlantic and inter-European bilateral teleoperation experiments are also reported (Montreal, Canada - Tirgu Mures, Romania; Budapest, Hungary - Tirgu Mures, Romania). The experimental measurements show the applicability of the control approach and its benefits on the teleoperation performances.

    Keywords: Telerobotics; Internet; Networked control systems; Delay systems; Passivity

  • Jan Tomlain ,
    Ondrej Teren ,
    Radek Sedlacek ,
    Josef Vedral :

    Abstract: This paper describes a development of a hardware platform suitable for the frequency domain spectroscopy (FDS) and frequency response analysis (FRA) applied for high-voltage machine diagnostics. The principle of the FDS and FRA methods widely used by maintenance technicians are briefly reviewed. Important technical requirements for the instruments utilizing these methods are stated. A design of a hardware platform with parameters fitting both of the method and engagement of the latest electronics components is discussed. In order for verification of the design platform, a basic implementation of a vector voltmeter is described. Long-term stability, phase shift sensitivity, and accuracy of the platform are evaluated.

    Keywords: high-voltage machine diagnostics; dielectric spectroscopy; dielectric response analysis; frequency response analysis; non-invasive diagnostic; machine insulation; lock-in amplifier

  • Erika Seres-Huszárik ,
    László Józsa ,
    Zsuzsanna Tóth :

    Abstract: Factors affecting the success of business relationships for a long while have been in the focus of those specialists and professionals who are interested in the topic over the last two decades have caused significant changes in everyday life of participants in the economy. Over the past decades the concept of relationship marketing has become well-known and widely spread in business life. It is a well-known fact that the cost of acquiring a new customer is much higher than the cost of keeping an existing one. Participants of the economy define relationship marketing as a strategy to achieve customer loyalty. During the initial phase of the relationship, the company aims to establish a strong relationship with the customer, to win indifferent customers and make them loyal. Based on the above-mentioned factors, we found it important to asses the factors affecting the agency-client relationship. Based on several empirical studies, in our research we tried to answer the question whether it can be stated on the basis of the unanimous opinion of the participants of the Slovak advertising market that during the development of business relationships interpersonal relationships play the most important role ((hypothesis testing). Results of our research will help us understand the development of the agency-client relationships, and provide practical results for the advertising industry.

    Keywords: advertising agency; client; relationship

  • Vidan Marković ,
    Zora Konjović :
    A Contribution to Software Development Quality Management83-105en [540.66 kB - PDF]EPA-02461-00077-0050

    Abstract: Disruptive digital technologies have increased the potential for international businesses to access clients’ data in traditionally closed local markets (e.g. insurance, banking, etc.) without the need for a physical presence. In order to stay competitive in the long run, local companies have to invest more in both technology and sourcing strategies. In this paper, we propose an enhancement to the software development suppliers management process based on a continuous services comparison that can lead to proactive improvements in suppliers’ quality of services. This paper explains this process and demonstrates a company case study experiment.

    Keywords: Software Quality; Software Processes; Outsourcing

  • Anita Kolnhofer-Derecskei ,
    Regina Zs. Reicher ,
    Agnes Szeghegyi :
    The X and Y Generations’ Characteristics Comparison107-125en [576.47 kB - PDF]EPA-02461-00077-0060

    Abstract: The aim of this paper is to identify generational differences, also similarities among university students in order to realise the reason of generational gap. Data for this study were collected through survey analysis (n=783). Findings indicated significant differences among X and Y generations usage of new technological innovation (i.e. also applications and devices). While Generation Y members (Millennials) are technology and social media addicted, the members of elder generation are in a different life period and due to this they are calmer, and more family oriented. Although generational gap is one of the fanciest management topic it is necessary to highlight that some characteristics are not as socially back-grounded rather than typically age relevant. On the other hand, generation gap is not so sharp the two, there is only a slight shift from X to Y or Z generations. That means the so-called cuspers (between generations’ members) should also be taken into consideration.

    Keywords: Generation differences; Millennials; Cuspers; X generation

  • Maksim Dudkin ,
    Aleksandr Nesterov ,
    Aleksandr Shishkov :
    Phase-locked Loop Based on Integrating Scanning Conversion127-142en [674.34 kB - PDF]EPA-02461-00077-0070

    Abstract: A new principle for developing a phase-locked loop (PLL) based on integrating scan conversion is proposed. The PLL is a nonlinear pulse system based on the closed structure of an integrating scanning converter (ISC) operating in the mode of external synchronization with circuit voltage frequency. The block diagrams, the waveform diagram and frequency synchronization conditions for integrating scanning converter switch by outer signals - bipolar rectangle and harmonic, are provided. The recommendations for choosing the frequency ratio of self-oscillations of the scanning converter and circuit voltage frequency were tested. It is shown that the integrating PLL fully adapts to amplitude instability and circuit voltage frequency within the range of ±50% and higher. Unlike the existing PLLs, the proposed system is a first-order adaptive filter, whose bandwidth is automatically tuned to the amplitude and frequency of circuit voltage. This property of the integrating PLL allows suppressing higher harmonics in the supply circuit with frequency instability within the range of ±50% and higher. The system’s high noise immunity to commutation distortions of circuit voltage is also shown. These results show the practicability of using it in semiconductor converter control systems, which receive power from an independent low-power supply system, for example, diesel or wind power generating plants. The limits of the dynamic parameters of this system for gradual change of amplitude and circuit voltage frequency have been determined. A three-phase reverse thyristor rectifier is used as an example of a crossed synchronization flow-chart. The recommendations on choosing the parameters of the integrating PLL and also the results of the practical application of the synchronizing unit as a part of semiconductor converter control systems are provided.

    Keywords: control system; integrator; scanning converter; semiconductor converter; phase-locked loop

  • Vojkan Nikolić ,
    Branko Markoski ,
    Kristijan Kuk ,
    Dragan Ranđelović ,
    Petar Čisar :

    Abstract: Today, e-Governments services operate quick answer systems in many different domains in order to help citizens receive answers to their questions at any time and within a very short time. The automatic mapping of relevant documents stands out as an important application for automatic questions-documents classification strategies. This paper presents a contribution to the identification concepts in text comprehension in unstructured documents as an important step towards clarifying the role of explicit concepts in information retrieval in general. The most common representational scheme in text categorization is the Bag of Words approach when the dictionary, as incorporating background knowledge, is large. The authors introduce a new approach to create concept-based text representations, and apply it to a text categorization collection to create predefined classes in the case of short text document analysis problem. Further in this paper, a classification-based algorithm for questions matching topic modelling is presented. The paper also describes the weighting of concepts that present terms with high frequency of occurrence in questions is based on their similarity relevance in the predefined classes of documents. The results of the experiment within the criminal law domain in the present case study show that the performance of concept-based text representations has proven to be satisfactory in the case when there is no dictionary for this domain.

    Keywords: e-Government services; criminal law domain; natural language processing (NLP); Bag of Concept (BOC) approach

  • Ján Perháč ,
    Daniel Mihályi ,
    Valerie Novitzká :

    Abstract: Component-based programming has become a popular and frequently used method for software development, prepared from independent components by a composition. Our paper presents an illustration of how a composition of components can cause the emergence of new problems that should be solved, in order to obtain the desired results. We introduce a transformation of Petri nets to corresponding provable sequents of linear logic and then we show how a composition of simple Petri nets causes arising of synchronization problems. Transformation to provable linear sequents that ensures a verified behavior for such composed systems.

    Keywords: linear logic; petri nets; component composition

  • Małgorzata Kowalska ,
    Magdalena Wozniak ,
    Magdalena Pazdzior :

    Abstract: The aims of this work were a sensory analysis, an evaluation of moistening properties and establishment of emulsions stability. Emulsions were prepared with two variable parameters (hemp oil content and time of homogenization). 15 respondents assessed emulsions sensory and skin moisturizing properties. Kleeman’s optimizing method was used to designate the most stable emulsion system with the variable parameters. Taking into consideration all properties of the presented emulsions, emulsion V (50g of hemp oil and homogenized for 6 minutes) was found to be the optimum composition with the best moistening and sensory properties. After the application of this emulsion, the skin was highly moistened. Consistency of the emulsions was homogeneous and free from clotting. According to Kleeman’s method, emulsion V was also confirmed as the most optimum variant of the emulsion. The work confirmed that hemp oil can be successfully used as a component for cosmetic emulsions.

    Keywords: hemp oil; emulsions; sensory evaluation; moisturizing parameters; emulsions stability

  • Lazar Tesic ,
    Boban Bondzulic ,
    Milenko Andric ,
    Boban Pavlovic :

    Abstract: This paper presents the results of a late large-scale subjective study of phase importance of speech quality. Present study includes a collection of speech sentences distorted by limited transmission bandwidth and phase degradations. A detailed statistical analysis of the collected subjective judgments is presented. Among the used signal distortions, subjects preferred modification with signal phase preservation. Mean opinion scores of such modification are the closest to the original, undistorted sentences. This subjective study contributes to improving the algorithms of the speech processing, and in addition provide valuable data to develop objective or automatic methods of speech quality assessment, as well as to estimate their performance.

    Keywords: phase spectrum; phase importance; speech signal; subjective evaluation

  • David Tuček ,
    Barbora Dombeková :
    Local Muscular Load Measurement with the Help of a Datalogger215-234en [371.15 kB - PDF]EPA-02461-00077-0120

    Abstract: The aim of this research was the development and verification of the local muscular load measuring methodology as a valid and recognized measurement in order to subsequently strengthen injury prevention of occupational diseases among workers of both manufacturing and non-manufacturing companies. A milestone in the project was construction of a measuring device to obtain data for evaluating local muscular load with the use of force measurement, frequency of movements and positions and a device called datalogger. This measuring device was then tested and its functionality has been successfully proved in 40 measurements in both manufacturing and non-manufacturing enterprises. The reason for the development of this equipment was especially a requirement to learn the load (force generation) of the individual fingers when operators work, implemented by different grips, e. g. tridigital, pentadigital and so on. Such quantification is not possible with the current EMG method. The developed equipment had to be validated with existing certified methodology called electromyography, which allows only summative evaluation. The results of correlations of both measurements while evaluating the local muscular load are analyzed in this article. The aim of this paper is also to describe how the new device was developed and tested: the Datalogger for measuring local muscular load and its advantages and limitations. Based on the defense carried out, the Industrial Property Office subsequently issued a letters patent for the invention with a number PV 2015-820 earlier this year. The invention relates to an ergonomic device developed for monitoring of local muscular load, and is especially useful in workplaces where there is increased stress, particularly stress on your hands when multiple / repetitive movements, often involving spending increased muscle strength. Measurements can also be made for operators wearing different preservative gloves commonly used in practice. In this article the authors will introduce not only new patented apparatus itself, but a new methodology for local muscular load measuring with the datalogger as well.

    Keywords: ergonomics; local muscular load, carpal tunnel syndrome; datalogger; longterm, integrated electromyography (EMG)