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Acta polytechnica HungaricaVolume 14, Issue No. 2. (2017.)


  • Tamás Péter ,
    Krisztián Szabó :

    Abstract: On the grounds of our traffic network model developments an exact mathematical model can be created based on the union of different types of transport networks. The initial network is the vehicle traffic network that integrates the public transport network as well. During this study the union of road and pedestrian networks is initially created and then we further examine the possibility of generalization of complex networks thereafter.

    Keywords: transport processes; network union model; analysis of movements on mixed trajectories; smart city

  • Alina Ţenescu ,
    Radu-Emil Precup ,
    Nicuşor Minculete :
    Evolving Fuzzy Models for Automated Translation27-46en [428.58 kB - PDF]EPA-02461-00071-0020

    Abstract: This paper targets two goals. First, it analyzes the most common errors in automated translation from French to English and from English to French performed by a statistical and a hybrid translation engine with the help of the evaluation metric SAE J2450. The test of concordance is applied in order to study the agreement between the original text and its retroversion within the same translation memory software. Seven categories of primary errors are considered, which cover the fields of terminology, semantics, structure, orthography, punctuation and completeness. Second, evolving fuzzy models are developed, which give the overall paragraph score using the seven categories of primary errors as inputs. The fuzzy models permit the users to establish the accuracy of translation and to grade the quality of translations resulted from the reintroduction of the result of translation in the same software application. They also allow the comparison of two popular translation memory programs, namely Google Translate (GT) and Systran, in the framework of the issues of concordance in translation and artificial learning.

    Keywords: accuracy; automated translation; concordance; errors; evolving fuzzy systems

  • Gergely Bojtár ,
    Béla M. Csizmadia ,
    János Égert :

    Abstract: The knowledge of orthotropic material properties of composite layers is very important for mechanical design of machine structures from composite material. This information cannot be found in related professional literature therefore it is necessary to determine by measurement, by basic experiments of mechanics of materials. The paper presents a new 3D finite element layer model-cell based on the meso-structure of a textile composite layer, with which one shall be able to determine the material constants of an orthotropic layer. The applicability of the numerical layer model-cell and the accuracy of the numerical results are confirmed by experimental results. The numerically determined material properties of the layers are used at mechanical modeling and computation of complex, layered composite structures.

    Keywords: orthotropic material properties; textile composite; composite layer; finite element method, layer model-cell; validation with experiments

  • Shu Yun Lim ,
    M. L Mat Kiah ,
    Tan Fong Ang :

    Abstract: Authentication, in the cloud context, is the process of validating and guaranteeing the identity of cloud service subscribers or users. It is deemed essential since its strength directly impacts the reliability and security of the cloud computing environment. Many efforts, within in the literature, have surveyed cloud security and privacy, but lack a detailed analysis of authentication for the cloud. In view of the research gap and the importance of a valid authentication infrastructure, this survey critically investigates different authentication strategies and frameworks proposed for cloud services. This paper discusses the pros and cons of different authentication strategies and presents the taxonomy of the state-of-the-art cloud service authentication. The paper concludes with the open issues, main challenges and directions highlighted for future work in this relevant area.

    Keywords: cloud computing; authentication; authentication-as-a-service; identity management; access control

  • Antal Ürmös ,
    Zoltán Farkas ,
    Ákos Nemcsics :
    Modeling of III-V-based Nanohole Filling91-111en [916.78 kB - PDF]EPA-02461-00071-0050

    Abstract: It is well-known, that several areas of science (for example electronics) have been revolutionized by the application of nano structures. For this reason, it is important to simulate the evolution of these nano structures. The III-V- composite semiconductor based nanohole backfilling is modeled in this paper. The backfilling is described with the viscosity of the liquid gallium, instead of modeling of the real atomic displacements. The construction of the model begins with the macroscopic interpretation of the viscosity. In order to model the atomic displacement at microscopic level, the microscopic viscosity was introduced. It is shown, that under certain conditions we get back the original Arrhenius-Andrande equation from the microscopic viscosity model. During the simulation, both the viscosity and the equilibrium height of the backfilled nanohole was determined as a function of temperature.

    Keywords: GaAs; nanohole backfilling; viscosity; modeling

  • Anna Grinčová ,
    Miriam Andrejiová ,
    Daniela Marasová :

    Abstract: Transportation is an important logistics activity within production systems, affecting continuity of the production process. High-capacity, cost-efficient, and energetically undemanding, continuous transportation systems include the conveyor belt system. A crucial and the most sensitive component thereof is a conveyor belt which is exposed, within the production processes, to the impacts that give rise to the damage and degradation process. Therefore, the issues related to increasing the service life and the operational reliability of conveyor belts are highly topical. The aim of the article is to discuss the issues regarding the measurement analysis within the testing of conveyor belts in terms of software optimization. The role of the created AnCoBE (Analysis of Conveyor Belt) software application is to apply selected mathematical and statistical methods and Java technology in order to support processing and evaluation of data obtained by experimental research of evaluation of utility properties of conveyor belts in terms of their dynamic stress. The experimental tests herein were focused on the determination of conveyor belt impact resistance and the description of damage caused to conveyor belts by the related stresses.

    Keywords: conveyor belts; regression model; software application

  • Judith Pálfi ,
    Miklós Tompa ,
    Péter Holcsik :

    Abstract: The improvement of the quality of services is the main target of the electricity suppliers. This can be achieved by minimizing the number and duration in time of the power outages. The reliability indicators show the quality of the system. The quality of the services can be increased by proper maintenance, proper renovation activities and the implementation of advanced tools and functions into the system. Smart switchboard (SSB) devices are provided with modern and innovative functions which support the activity of the low voltage (LV) distribution network operators. Remote control and monitoring, fault location identification support, supply of on-line load-flow input data, and automatic recloser are only some examples of the newly available technologies. In this paper the improvement of the LV reliability indicators by using the recloser function of the SBB’s is presented.

    Keywords: LV network; quality of service; smart switchboard; recloser; fault location

  • Figen Özen ,
    Dilek Bilgin Tükel ,
    Georgi Dimirovski :

    Abstract: An extended Labanotation for an industrial robot was developed and applied. A user-friendly program was designed to help design dance choreography. The program, LabanRobot, has a simple interface that can be used without any prior knowledge of the robot. The choreographer should keep geometry in mind and plan the dance sequence accordingly. The conversion of dance sequences to robot motion is done automatically by the program. Details of the algorithm are given. Examples of simulation and on-stage-performance are shown.

    Keywords: industrial robot; Labanotation; dance

  • Dóra Károly ,
    Lilla Asztalos ,
    Tamás Micsík ,
    Péter János Szabó :
    Non-Destructive Analysis of Explanted Coronary Artery Stents171-181en [674.68 kB - PDF]EPA-02461-00071-0090

    Abstract: Endovascular stents are used to effectively treat atherosclerosis during angioplasty. Nowadays, this surgery is performed on younger and younger patients, so the stent can be in the body for over 30 years. The stent cannot be removed from the patient, so the in vivo stability of the stent and the effects of the human organism on the stent can only be investigated on postmortem explanted stents. Therefore, this study deals with the non-destructive investigation of explanted coronary stents. Our goal was to determine the causes of visible damages and to measure the changes in the technical state.

    Keywords: explanted coronary stent; non-destructive test; fracture; coating damage

  • Marko Jocic ,
    Endre Pap ,
    Anikó Szakál ,
    Djordje Obradovic ,
    Zora Konjovic :
    Managing Big Data Using Fuzzy Sets by Directed Graph Node Similarity183-200en [587.81 kB - PDF]EPA-02461-00071-0100

    Abstract: This paper proposes a novel algorithm for discovering similar nodes in very large directed graphs, with millions of nodes with billions of connections, which is based on the fuzzy set theory. The required input is a sample of representative nodes that are highly affiliated with some feature. This approach is practically verified on Twitter social network case study to discover influential Twitter users in the field of science.

    Keywords: big data; directed graph; node similarity; Twitter

  • Anna Bánáti ,
    Péter Kacsuk ,
    Miklós Kozlovszky :
    Reproducibility Analysis of Scientific Workflows201-217en [578.58 kB - PDF]EPA-02461-00071-0110

    Abstract: Scientific workflows are efficient tools for specifying and automating compute and data intensive in-silico experiments. An important challenge related to their usage is their reproducibility. In order to make it reproducible, many factors have to be investigated which can influence and even prevent this process: the missing descriptions and samples; the missing provenance data about the environmental parameters and the data dependencies; the dependencies of executions which are based on special hardware, changing or volatile third party services or random generated values. Some of these factors (called dependencies) can be eliminated by careful design or by huge resource usage but most of them cannot be bypassed. Our investigation deals with the critical dependencies of execution. In this paper we set up a mathematical model to evaluate the results of the workflow in addition we provide a mechanism to make the workflow reproducible based on provenance data and statistical tools.

    Keywords: scientific workflows; reproducibility; analytical model; provenance; evaluation; gUSE