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Abstrakt

In this paper a prototype framework for simulation of wireless sensor network and its protocols are presented. The framework simulates operation of a sensor network with data transmission, which enables simultaneous development of the sensor network software, its hardware and the protocols for wireless data transmission. An advantage of using the framework is converging simulation with the real software. Instead of creating a model of the sensor network node, the same software is used in real sensor network nodes and in the simulation framework. Operation of the framework is illustrated with examples of simulations of selected transactions in the sensor network.
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Autorzy i Afiliacje

Marek Wójcikowski

Abstrakt

The adjustment problem of the so-called combined (hybrid, integrated) network created with GNSS vectors and terrestrial observations has been the subject of many theoretical and applied works. The network adjustment in various mathematical spaces was considered: in the Cartesian geocentric system on a reference ellipsoid and on a mapping plane. For practical reasons, it often takes a geodetic coordinate system associated with the reference ellipsoid. In this case, the Cartesian GNSS vectors are converted, for example, into geodesic parameters (azimuth and length) on the ellipsoid, but the simple form of converted pseudo-observations are the direct differences of the geodetic coordinates. Unfortunately, such an approach may be essentially distorted by a systematic error resulting from the position error of the GNSS vector, before its projection on the ellipsoid surface. In this paper, an analysis of the impact of this error on the determined measures of geometric ellipsoid elements, including the differences of geodetic coordinates or geodesic parameters is presented. Assuming that the adjustment of a combined network on the ellipsoid shows that the optimal functional approach in relation to the satellite observation, is to create the observational equations directly for the original GNSS Cartesian vector components, writing them directly as a function of the geodetic coordinates (in numerical applications, we use the linearized forms of observational equations with explicitly specified coefficients). While retaining the original character of the Cartesian vector, one avoids any systematic errors that may occur in the conversion of the original GNSS vectors to ellipsoid elements, for example the vector of the geodesic parameters. The problem is theoretically developed and numerically tested. An example of the adjustment of a subnet loaded from the database of reference stations of the ASG-EUPOS system was considered for the preferred functional model of the GNSS observations.
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Autorzy i Afiliacje

Roman Kadaj

Abstrakt

The main idea of all Active Queue Management algorithms, is to notify the TCP sender about incoming congestion by dropping packets, to prevent from the buffer overflow, and its negative consequences. However, most AQM algorithms proposed so far, neglect the impact of the high speed and long delay links. As a result, the algorithms’ efficiency, in terms of throughput and/or queue stability, is usually significantly decreased. The contribution of this paper is twofold. First of all, the performance of the well known AQM algorithms in high speed and long delay scenarios is evaluated and compared. Secondly, a new AQM algorithm is proposed, to improve the throughput in the large delay scenarios and to exclude the usage of random number generator.
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Autorzy i Afiliacje

Agnieszka Brachman
Łukasz Chrost

Abstrakt

Disorders of the heart and blood vessels are the leading cause of health problems and death. Early detection of them is extremely valuable as it can prevent serious incidents (e.g. heart attack, stroke) and associated complications. This requires extending the typical mobile monitoring methods (e.g. Holter ECG, tele-ECG) by introduction of integrated, multiparametric solutions for continuous monitoring of the cardiovascular system.

In this paper we propose the wearable system that integrates measurements of cardiac data with actual estimation of the cardiovascular risk level. It consists of two wirelessly connected devices, one designed in the form of a necklace, the another one in the form of a bracelet (wrist watch). These devices enable continuous measurement of electrocardiographic, plethysmographic (impedance-based and optical-based) and accelerometric signals. Collected signals and calculated parameters indicate the electrical and mechanical state of the heart and are processed to estimate a risk level. Depending on the risk level an appropriate alert is triggered and transmitted to predefined users (e.g. emergency departments, the family doctor, etc.).

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Autorzy i Afiliacje

Jerzy Wtorek
Adam Bujnowski
Jacek Rumiński
Artur Poliński
Mariusz Kaczmarek
Antoni Nowakowski

Abstrakt

The In this paper stabilisation problem of LC ladder network is established. We studied the following cases: stabilisation by inner

resistance, by velocity feedback and stabilisation by dynamic linear feedback, in particularly stabilisation by first range dynamic feedback. The global asymptotic stability of the respectively system is proved by LaSalle’s theorem. In the proof the observability of the dynamic system plays an essential role. Numerical calculations were made using the Matlab/Simulink program.

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Autorzy i Afiliacje

W. Mitkowski

Abstrakt

Leak detection in transmission pipelines is important for safe operation of pipelines. The probability of leaks may be occurred at any time and location, therefore pipeline leak detection systems play a key role in minimization of the occurrence of leaks probability and their impacts. During the operation of the network there are various accidents or intentional actions that lead to leaks of gas pipelines. For each network failure, a quick reaction is needed before it causes more damage. Methods that are used to detect such network failures are three-staged-: early identification of leakage, an accurate indication of its location and determine the amount of lost fluid. Methods for leak detection can be divided into two main groups: external methods (hardware) and internal methods (software). External leak detection methods require additional, often expensive equipment mounted on the network, or use systems that could display only local damage on the pipeline. The alternative are the internal methods which use available network measurements and signalling gas leakage signal based on the mathematical models of the gas flow. In this paper, a new method of leak detection based on a mathematical model of gas flow in a transient state has been proposed.

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Autorzy i Afiliacje

Małgorzata Amanda Kwestarz
Andrzej Janusz Osiadacz
Łukasz Kotyński
Pobierz PDF Pobierz RIS Pobierz Bibtex

Abstrakt

This paper deals with two control algorithms which utilize learning of their models’ parameters. An adaptive and artificial neural network control techniques are described and compared. Both control algorithms are implemented in MATLAB and Simulink environment, and they are used in the simulation of a postion control of the LWR 4+ manipulator subjected to unknown disturbances. The results, showing the better performance of the artificial neural network controller, are shown. Advantages and disadvantages of both controllers are discussed. The usefulness of the learning algorithms for the control of LWR 4+ robots is discussed. Preliminary experiments dealing with dynamic properties of the two LWR 4+ robots are reported.

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Bibliografia

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[6] J.Swevers,W. Verdonck, and J. de Schutter. Dynamic model identification for industrial robots. IEEE Control Systems Magazine, 27(5):58–71, 2007. doi: 10.1109/MCS.2007.904659.
[7] A. Liegeois, E. Dombre, and P. Borrel. Learning and control for a compliant computer controlled manipulator. IEEE Transactions on Automatic Control, 25(6):1097–1102, 1980. doi: 10.1109/TAC.1980.1102513.
[8] A.J. Koivo and T.H. Guo. Control of robotic manipulator with adaptive controller. In 1981 20th IEEE Conference on Decision and Control including the Symposium on Adaptive Processes, pages 271–276, San Diego, USA, 16–18 Dec. 1981. doi: 10.1109/CDC.1981.269527.
[9] C.S.G. Lee and M.J. Chung. An adaptive control strategy for computer-based manipulators. In 1982 21st IEEE Conference on Decision and Control, pages 95–100, Orlando, USA, 8–10 Dec. 1982. doi: 10.1109/CDC.1982.268407.
[10] A. Koivo and T.H. Guo. Adaptive linear controller for robotic manipulators. IEEE Transactions on Automatic Control, 28(2):162–171, 1983. doi: 10.1109/TAC.1983.1103211.
[11] J.-J.E. Slotine and W. Li. On the adaptive control of robot manipulators. The International Journal of Robotics Research, 6(3):49–59, 1987. doi: 10.1177/027836498700600303. [12] F.W. Lewis, S. Jagannathan, and A. Yesildirak. Neural Network Control of Robot Manipulators and Non-Linear Systems. Taylor & Francis, Inc, 1998.
[13] G. Dreyfus, G. Neural Networks. Methodology and Applications. Springer-Verlag, Berlin, Heidelberg, 2005. doi: 10.1007/3-540-28847-3.
[14] M.A. Johnson and M.B. Leahy. Adaptive model-based neural network control. IEEE International Conference on Robotics and Automation Proceedings, volume 3, pages 1704-1709, Cincinnati, USA, 13–18 May 1990. doi: 10.1109/ROBOT.1990.126255.
[15] M.B. Leahy, M A. Johnson, D.E. Bossert, and G.B. Lamont. Robust model-based neural network control. In 1990 IEEE International Conference on Systems Engineering, pages 343– 346, Pittsburgh, USA, 9–11 Aug. 1990. doi: 10.1109/ICSYSE.1990.203167.
[16] R.T. Newton and Y. Xu. Neural network control of a space manipulator. IEEE Control Systems Magazine, 13(6):14–22, 1993. doi: 10.1109/37.247999.
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[19] A. Bottero, G. Gerio, V. Perna, and A. Gagliano. Adaptive control techniques and feed forward compensation of periodic disturbances in industrial manipulators. In 2014 IEEE/ASME 10th International Conference on Mechatronic and Embedded Systems and Applications (MESA), pages 1–7, Senigallia, Italy, 10–12 Sept. Sept. 2014. doi: 10.1109/MESA.2014.6935612.
[20] J. Li, H. Ma, C. Yang, and M. Fu. Discrete-time adaptive control of robot manipulator with payload uncertainties. In 2015 IEEE International Conference on Cyber Technology in Automation, Control, and Intelligent Systems (CYBER), pages 1971–1976, Shenyang, China, 8–12 June 2015. doi: 10.1109/CYBER.2015.7288249.
[21] M. Li, Y. Li, S.S. Ge, and T.H. Lee. Adaptive control of robotic manipulators with unified motion constraints. IEEE Transactions on Systems, Man, and Cybernetics: Systems, 47(1):184– 194, 2017. doi: 10.1109/TSMC.2016.2608969.
[22] Ł.Wolinski. Implementation of the adaptive control algorithm for theKUKALWR4+rRobot. In J. Awrejcewicz, ed., Dynamical Systems in Theoretical Perspective, volume 248 of Springer Proceedings in Mathematics & Statistics, pages 391–401, Springer, Cham, 2018. doi: 10.1007/978-3-319-96598-7_31.
[23] M. de Paula Assis Fonseca, B.V. Adorno, and P. Fraisse. An adaptive controller with guarantee of better conditioning of the robot manipulator joint-space inertia matrix. In 2019 19th International Conference on Advanced Robotics (ICAR), pages 111–116, Belo Horizonte, Brazil, 2–6 Dec. 2019. doi: 10.1109/ICAR46387.2019.8981558.
[24] L. Zhang and L. Cheng. An adaptive neural network control method for robotic manipulators trajectory tracking. In 2019 Chinese Control And Decision Conference (CCDC), pages 4839– 4844, Nanchang, China, 3–5 June 2019. doi: 10.1109/CCDC.2019.8832715.
[25] He Jun-Pei, Huo Qi, Li Yan-Hui, Wang Kai, Zhu Ming-Chao, and Xu Zhen-Bang. Neural network control of space manipulator based on dynamic model and disturbance observer. IEEE Access, 7:130101–130112, 2019. doi: 10.1109/ACCESS.2019.2937908.
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[27] Ł. Wolinski and P. Malczyk. Dynamic modeling and analysis of a lightweight robotic manipulator in joint space. Archive of Mechanical Engineering, 62(2):279–302, 2015. doi: 10.1515/meceng-2015-0016.
[28] G. Rodriguez, A. Jain, and K. Kreutz-Delgado. A spatial operator algebra for manipulator modelling and control. I nternational Journal of Robotics Research, 10(4):371–381, 1991. doi: 10.1177/027836499101000406.
[29] Lightweight Robot 4+ Specification, Version: Spez LBR 4+ V2en, 06.07.2010.
[30] A. Jubien, M. Gautier, and A. Janot. Dynamic identification of the Kuka lightweight robot: comparison between actual and confidential Kuka’s parameters. In Proceedings of the IEEE/ASME International Conference on Advanced Intelligent Mechatronics 2014, pages 483–488, Besancon, France, 8-11 July 2014. doi: 10.1109/AIM.2014.6878124.
[31] H. Kawasaki, T. Bito, and K. Kanzaki. An efficient algorithm for the model-based adaptive control of robotic manipulators. IEEE Transactions on Robotics and Automation, 12(3):496– 501, 1996. doi: 10.1109/70.499832.
[32] B. Siciliano, L. Sciavicco, L.Villani, and G. Oriolo. Robotics. Modelling, Planning and Control. Springer-Verlag, London, 2009. doi: 10.1007/978-1-84628-642-1.
[33] M. Gautier and W. Khalil. Direct calculation of minimum set of inertial parameters of serial robots. IEEE Transactions on Robotics and Automation, 6(3):368–373, 1990. doi: 10.1109/70.56655.
[34] Ł. Wolinski and M. Wojtyra. Comparison of dynamic properties of two KUKA lightweight robots. In ROMANSY 21 – Robot Design, Dynamics and Control. Proceedings of the 21st CISM-IFToMM Symposium, volume 569, pages 413–420, 2016. doi: 10.1007/978-3-319-33714-2_46.
[35] V. Záda and K. Belda. Mathematical modeling of industrial robots based on Hamiltonian mechanics. In 2016 17th International Carpathian Control Conference (ICCC), pages 813– 818, 2016. doi: 10.1109/CarpathianCC.2016.7501208.
[36] V. Záda and K. Belda. Application of Hamiltonian mechanics to control design for industrial robotic manipulators. In 2 017 22nd International Conference on Methods and Models in Automation and Robotics (MMAR), pages 390–395, Miedzyzdroje, Poland, 28–31 Aug. 2017. doi: 10.1109/MMAR.2017.8046859.
[37] K. Chadaj, P. Malczyk, and J. Frączek. A parallel recursive hamiltonian algorithm for forward dynamics of serial kinematic chains. IEEE Transactions on Robotics, 33(3):647–660, 2017. doi: 10.1109/TRO.2017.2654507.
[38] G. Schreiber, A. Stemmer, and R. Bischoff. The fast research interface for the KUKAl ightweight robot. In Proceedings of the IEEE ICRA 2010Workshop on ICRA 2010Workshop on Innovative Robot Control Architectures for Demanding (Research) Applications – How to Modify and Enhance Commercial Controllers, pages 15–21, May 2010.
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Autorzy i Afiliacje

Łukasz Woliński
1

  1. Institute of Aeronautics and Applied Mechanics, Warsaw University of Technology, Poland.

Abstrakt

The paper attempts to determine an optimum structure of a directional measurement and control network intended for investigating horizontal displacements. For this purpose it uses the notion of entropy as a logarithmical measure of probability of the state of a particular observation system. An optimum number of observations results from the difference of the entropy of the vector of parameters X X ˆ H ' corresponding to one extra observation. An increment of entropy interpreted as an increment of the amount of information about the state of the system determines the adoption or rejection of another extra observation to be carried out.
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Autorzy i Afiliacje

Maria Mrówczyńska

Abstrakt

The paper presents the operation of two neuro-fuzzy systems of an adaptive type, intended for solving problems of the approximation of multi-variable functions in the domain of real numbers. Neuro-fuzzy systems being a combination of the methodology of artificial neural networks and fuzzy sets operate on the basis of a set of fuzzy rules “if-then”, generated by means of the self-organization of data grouping and the estimation of relations between fuzzy experiment results. The article includes a description of neuro-fuzzy systems by Takaga-Sugeno-Kang (TSK) and Wang-Mendel (WM), and in order to complement the problem in question, a hierarchical structural self-organizing method of teaching a fuzzy network. A multi-layer structure of the systems is a structure analogous to the structure of “classic” neural networks. In its final part the article presents selected areas of application of neuro-fuzzy systems in the field of geodesy and surveying engineering. Numerical examples showing how the systems work concerned: the approximation of functions of several variables to be used as algorithms in the Geographic Information Systems (the approximation of a terrain model), the transformation of coordinates, and the prediction of a time series. The accuracy characteristics of the results obtained have been taken into consideration.
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Autorzy i Afiliacje

Maria Mrówczyńska

Abstrakt

Recent research has shown that the increase in a number of participants of construction project elevated the cost and duration of construction. The use of integrated project delivery and the formation of a network organization structure can significantly reduce the costs, as the activities of the participants become more coherent and coordinated. The optimization of decisions is essential for the efficiency of a negotiation process, which in turn depends on the organizational structure. The article specifies three basic types of network organizational structure that can be applied in a construction project: focal (F1), dynamic (F2), multifocal (F3). In this study, a direct assessment of possible effectiveness of each of the three types of network organizational structures was carried out using a vector decision model. For each of the above-mentioned types of organizational structures, the potential effectiveness of negotiating act f0 and the total potential effectiveness F0 was calculated. The results of the study show that the most effective type of network organizational structure is the multifocal collective decisions in which a project manager has several “assistants”.
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Autorzy i Afiliacje

Roman Trach
1
ORCID: ORCID
Mieczysław Połoński
2
ORCID: ORCID
Petro Hrytsiuk
3
ORCID: ORCID

  1. PhD., Warsaw University of Life Sciences-SGGW, Institute of Civil Engineering, ul. Nowoursynowska 159, 02-776 Warsaw, Poland
  2. Prof. PhD. Eng., Warsaw University of Life Sciences-SGGW, Institute of Civil Engineering, Nowoursynowska 159,02-776 Warsaw, Poland
  3. Prof. PhD., National University of Water and Environmental Engineering, Soborna 11, 33028 Rivne, Ukraine

Abstrakt

The three-dimensional (3D) coordinate measurement of radio frequency identification (RFID) multi-tag

networks is one of the important issues in the field of RFID, which affects the reading performance of

RFID multi-tag networks. In this paper, a novel method for 3D coordinate measurement of RFID multitag

networks is proposed. A dual-CCD system (vertical and horizontal cameras) is used to obtain images of

RFID multi-tag networks from different angles. The iterative threshold segmentation and the morphological

filtering method are used to process the images. The template matching method is respectively used to

determine the two-dimensional (2D) coordinate and the vertical coordinate of each tag. After that, the

3D coordinate of each tag is obtained. Finally, a back-propagation (BP) neural network is used to model

the nonlinear relationship between the RFID multi-tag network and the corresponding reading distance.

The BP neural network can predict the reading distances of unknown tag groups and find out the optimal

distribution structure of the tag groups corresponding to the maximum reading distance. In the future work,

the corresponding in-depth research on the neural network to adjust the distribution of tags will be done.

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Autorzy i Afiliacje

Zhuang Xiao
Xiaolei Yu
Zhimin Zhao
Wenjie Zhang
Zhenlu Liu
Dongsheng Lu
Dingbang Dong

Abstrakt

The active distribution network (ADN) represents the future development of distribution networks, whether the islanding phenomenon occurs or not determines the control strategy adopted by the ADN. The best wavelet packet has a better time-frequency characteristic than traditional wavelet analysis in the different signal processing, because it can extract better and more information from the signal effectively. Based on wavelet packet energy and the neural network, the islanding phenomenon of the ADN can be detected. Firstly, the wavelet packet is used to decompose current and voltage signals of the public coupling point between the distributed photovoltaic (PV) system and power grid, and calculate the energy value of each decomposed frequency band. Secondly, the network is trained using the constructed energy characteristic matrix as a neural network learning sample. At last, in order to achieve the function of identification for islanding detection, lots of samples are trained in the neural network. Based on the actual circumstance of PV operation in the ADN, the MATLAB/SIMULINK simulation model of the ADN is established. After the simulation, there are good output results, which show that the method has the characteristics of high identification accuracy and strong generalization ability.

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Autorzy i Afiliacje

Zhongmei Xi
Faqi Zhao
Xiangyang Zhao
Hong Peng
Chuanxin Xi

Abstrakt

Land surveyors, photogrammetrists, remote sensing engineers and professionals in the Earth sciences are often faced with the task of transferring coordinates from one geodetic datum into another to serve their desired purpose. The essence is to create compatibility between data related to different geodetic reference frames for geospatial applications. Strictly speaking, conventional techniques of conformal, affine and projective transformation models are mostly used to accomplish such task. With developing countries like Ghana where there is no immediate plans to establish geocentric datum and still rely on the astro-geodetic datums as it national mapping reference surface, there is the urgent need to explore the suitability of other transformation methods. In this study, an effort has been made to explore the proficiency of the Extreme Learning Machine (ELM) as a novel alternative coordinate transformation method. The proposed ELM approach was applied to data found in the Ghana geodetic reference network. The ELM transformation result has been analysed and compared with benchmark methods of backpropagation neural network (BPNN), radial basis function neural network (RBFNN), two-dimensional (2D) affine and 2D conformal. The overall study results indicate that the ELM can produce comparable transformation results to the widely used BPNN and RBFNN, but better than the 2D affine and 2D conformal. The results produced by ELM has demonstrated it as a promising tool for coordinate transformation in Ghana.

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Autorzy i Afiliacje

Yao Yevenyo Ziggah
Yakubu Issaka
Prosper Basommi Laari
Zhenyang Hui
Słowa kluczowe helicopter rotor neural network

Abstrakt

The paper presents the possibilities of neural network application in recognition of rotor blade faults. Computer calculated data of rotor response due to faults were used for neural network training. The rotor was modeled by elastic axes with distribution of Jumped masses. The rotor defects were simulated by changing aerodynamic, inertial or stiffness properties of one of the blades. Time results were subjected to spectral analysis for the purpose of neural networks training.
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Autorzy i Afiliacje

Jarosław Stanisławski

Abstrakt

Tematem pracy jest dyskusja nad wynikami analizy struktury geometrycznej pomiarowych sieci modularnych w aspekcie określenia kryteriów technicznej poprawności tego typu konstrukcji. Podstawą przeprowadzonej analizy są algebraiczne zależności zachodzące pomiędzy elementami sieci (m.in. liczba stanowisk, punktów wiążących, liczba obserwacji). Przedstawiono także warunki wyznaczalności dla pojedynczych modułów oraz dla sieci powierzchniowych z założeniem istnienia modułów elementarnych niewyznaczalnych wewnętrznie. W części empirycznej przeprowadzono przy użyciu programu komputerowego, test porównawczy dla modeli sieci klasycznej i modularnej. Uzyskane wyniki stanowią ilustrację dokładności wyznaczenia położenia punktów za pomocą sieci modularnej. Przedstawione wnioski mogą być pomocne przy projektowaniu geodezyjnych osnów pomiarowych.
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Autorzy i Afiliacje

Tadeusz Gargula
ORCID: ORCID

Abstrakt

The aim of presented work was to evaluate the current tourist-leisure management and on this basis to designate the concept of management the Natura 2000 „Puszcza Notecka” area at Drawsko commune area. The natural-landscape valorisation revealed a very high level of environmental values. However, this potential is currently not fully utilized. For enrichment of current tourist infrastructure and full using potential of analyzed area the followed activities were here proposed: designation of new tourist routes, location a resort and small architecture objects.
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Autorzy i Afiliacje

Marta Lisiak
Klaudia Borowiak
Weronika Boruszak
Jolanta Kanclerz

Abstrakt

We propose the time slot routing, a novel routing scheme that allows for a simple design of interconnection networks. The simulative results show that the proposed scheme demonstrates optimal performance at the maximal uniform network load, and for uniform loads the network throughput is greater than for deflection routing.
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Autorzy i Afiliacje

Ireneusz Szcześniak
Roman Wyrzykowski
Pobierz PDF Pobierz RIS Pobierz Bibtex

Abstrakt

Trust and willingness to cooperate depend on the structure of one’s social network and the resources one can access through it. In this study, based on a survey dataset of a representative sample of the Polish population (n = 1000) we create an empirical ‘map’ of four distinct dimensions of social capital: degree (number of social ties), centrality in the social network, bridging social capital (ties with dissimilar others), and bonding social capital (ties with similar others, primarily with kin). We investigate the links between social capital and its key correlates: generalized and particularized trust and willingness to cooperate. We find that centrality (or occupying the position of a network bridge) is positively related to trust, whereas for bonding social capital this relation is negative. We find also a puzzling effect of cooperation without trust in the case of individuals with high bridging social capital resources (ties with dissimilar others).
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Bibliografia

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Autorzy i Afiliacje

Katarzyna Growiec
1
ORCID: ORCID
Jakub Growiec
2
ORCID: ORCID
Bogumił Kamiński
2
ORCID: ORCID

  1. SWPS Uniwersytet Humanistycznospołeczny
  2. Szkoła Główna Handlowa w Warszawie

Abstrakt

The number of publications inspired by Bruno Latour’s social thought has significantly grown in Poland over the last decade. Among them there are theoretical analyses, research programms as well as projects of social engineering. This situation makes it urgent to examine the credibility of Latour’s vision of science and society. The present article claims that the premises as well as arguments of the French thinker are not only fallacious but also dangerous. A number of absurdities following from the actor-network theory become evident in the works of the Polish followers of Latour. Thus the article focuses on selected examples of them. In the conclusion the author indicates certain advantages for Latour’s readers and formulates several hypotheses about the possible reasons for Latour’s growing popularity.

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Autorzy i Afiliacje

Michał Kaczmarczyk

Abstrakt

W pracy przeprowadzono analizę danych pomiarowych stężeń ołowiu i kadmu w powietrzu w celu określenia stopnia zróżnicowania stężeń tych metali w sezonie grzewczym i letnim. Analiza wykazała brak istotnych różnic między średniodobowymi stężeniami kadmu w sezonie grzewczym i w sezonie letnim. Jednocześnie wykazano, że różnice między średniodobowymi stężeniami ołowiu w sezonie grzewczym i w sezonie letnim są istotne. W dalszej części pracy zastosowano uniwersalną metodę przedstawienia stężeń średniodobowych ołowiu w okresie grzewczym jako sumy zmiennej losowej reprezentującej roczne tło średniodobowych stężeń ołowiu i zmiennej losowej reprezentującej stężenia ołowiu powodowane przez źródła działające jedynie w okresie grzewczym. W przypadku punktu pomiarowego, w którym wykonano pomiary stężeń Pb i Cd, źródłami takimi były zwłaszcza paleniska domowe. Do wyznaczenia dystrybuanty średniodobowych stężeń ołowiu powodowanych przez źródła działające jedynie w okresie grzewczym wykorzystano dwuwarstwową sieć neuronową. Wykazano, że średniodobowe stężenia ołowiu powodowane przez emisje z palenisk domowych przez prawie 145 dni, tj. 80% czasu w sezonie grzewczym, były co najmniej dwukrotnie niższe niż stężenia ołowiu powodowane przez źródła działające w ciągu całego roku. Jedynie przez 14 dni w okresie grzewczym stężenia ołowiu powodowane przez źródła działające wyłącznie w tym okresie były wyższe od stężeń tła w tym czasie.
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Autorzy i Afiliacje

Czesław Kliś
Stanisław Hławiczka

Abstrakt

Noise control has gained a lot of attention recently. However, presence of nonlinearities in signal paths for some applications can cause significant difficulties in the operation of control algorithms. In particular, this problem is common in structural noise control, which uses a piezoelectric shunt circuit. Not only vibrating structures may exhibit nonlinear characteristics, but also piezoelectric actuators. In this paper, active device casing is addressed. The objective is to minimize the noise coming out of the casing, by controlling vibration of its walls. The shunt technology is applied. The proposed control algorithm is based on algorithms from a group of soft computing. It is verified by means of simulations using data acquired from a real object.

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Autorzy i Afiliacje

Sebastian Kurczyk
Marek Pawełczyk

Abstrakt

This study investigates the estimated adsorption efficiency of artificial Nickel (II) ions with perlite in an aqueous solution using artificial neural networks, based on 140 experimental data sets. Prediction using artificial neural networks is performed by enhancing the adsorption efficiency with the use of Nickel (II) ions, with the initial concentrations ranging from 0.1 mg/L to 10 mg/L, the adsorbent dosage ranging from 0.1 mg to 2 mg, and the varying time of effect ranging from 5 to 30 mins. This study presents an artificial neural network that predicts the adsorption efficiency of Nickel (II) ions with perlite. The best algorithm is determined as a quasi-Newton back-propagation algorithm. The performance of the artificial neural network is determined by coefficient determination (R2), and its architecture is 3-12-1. The prediction shows that there is an outstanding relationship between the experimental data and the predicted values.

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Autorzy i Afiliacje

Sinan Mehmet Turp

Abstrakt

An available bandwidth at a link is an unused capacity. Its measuring and/or estimation is not simple in practice. On the other hand, we know that its continuous knowledge is crucial for the operation of almost all networks. Therefore, there is a continuous effort in improving the existing and developing new methods of available bandwidth measurement and/or estimation. This paper deals with these problems. Network calculus terminology allows to express an available bandwidth in terms of a service curve. The service curve is a function representing a service available for a traffic flow which can be measured/estimated in a node as well as at an endto- end connection of a network. An Internet traffic is highly unpredictable what hinders to a large extent an execution of the tasks mentioned above. This paper draws attention to pitfalls and difficulties with application of the existing network calculus methods of an available bandwidth estimation in a real Internet Service Provider (ISP) network. The results achieved in measurements have been also confirmed in simulations performed as well as by mathematical considerations presented here. They give a new perspective on the outcomes obtained by other authors and on their interpretations.

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Autorzy i Afiliacje

Katarzyna Wasielewska
Andrzej Borys

Abstrakt

The paper puts forward a method of designing and creating a complete computer system for monitoring and diagnosis of business and industrial facilities, as well as for control purposes. The proposed solution represents a computer-network system being a practical tool for communication, control and management of modern plants and enterprises. The applied concept of communication, based on the Service Oriented Architecture (SOA), makes a new attempt to solve certain performance problems met when using a (previously developed) Networked Object Monitor (NOM). The principal idea of increasing the performance of NOM lies in employing a common data bus, refereed to as a Diagnostic Service Bus (DSB), in the NOM monitor. The paper also describes a preliminary concept of a network description language (SMOL), which is designed to describe the functions, mechanisms, and network devices and to be a basis for simulation and verification of the NOMmonitor function.

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Autorzy i Afiliacje

Zdzisław Kowalczuk
Jakub Wszołek

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