October 2020
Guest Editor-in-Chief:
Cor. member Prof. Petko Petkov, D.Sc.
Preface for Issue 2
DOI: 10.47978/TUS.2020.70.02
Table of Contents
AUTOMATIC SOLUTION OF TRANSPORT PROBLEMS USING A NEW ADD-IN TO EXCEL
Simona Filipova-Petrakieva, Ivan Stankov
Abstract
Transport problem is a basic problem arising in transportation the products from several distributors to several clients. The solution of this problem consists of determining optimal transportation according to needed allocations the products. In fact, this problem describes with linear programming model which in general solves with simplex method. The algorithm of this method is a build-in tool for Excel – SOLVER. Unfortunately when it has a large amount of input data the filling of the Excel’s tables is a very difficult process. Thus, in this paper is suggested an add-in which visualize and make easier inputting the initial data. It is based on the Visual Studio tools for development the add-ins for MS Office. The main advantage of this solution consists of a user-friendly interface of the mathematical model of the problem which significantly makes easily and good visualization the input data and final solution in tables. As an illustrative example, the proposed add-in is applied for solving the real problem connected with transportation the products of pharmacy company.
Keywords
transport problems (closed and open – with insufficiency or overstock); Simplex method; Add-in to Excel for good data visualization, created by Visual Studio Tools for MS Office.
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DOI: 10.47978/TUS.2020.70.02.007
References:
[1] Taha, H. Operations research: an introduction, 10-th edition, Pearson, Print ISBN: 9780134444017, 0134444019, eText ISBN: 9780134480190, 0134480198, 2017.
[2] Transportation Problem. (n.d.) McGraw-Hill Dictionary of Scientific & Technical Terms, 6E. (2003). Retrieved April 6 2020 from
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[3] Transportation Problem. (n.d.) The Great Soviet Encyclopedia, 3rd Edition. (1970-1979). Retrieved April 6 2020 from
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[4] Petrakieva, S., G. Georgieva-Taskova. Automatic solution of transport problems with Excel, 13-th International Conference "Challenges in Higher Education Research in 21-st century", Sozo-pol, Bulgaria, ISBN: 978-954-580-356-7, pp. 91-95, June 2015.
[5] Georgiev I., St. Karakoleva. Solving transport problems with Matlab, Proceeding of Scientific Student Session, Rousse, ISSN: 1311-3321, pp. 30-35, 1999.
[6] Kolman, B., R. Beck. Special Types of Linear Programming Problems, in Elementary Linear Programming with Applications (Second Edition), 1995.
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https://www.sciencedirect.com/topics/computer-science/transportation-problem
[7] Tavana, M., K. Puranam, Handbook of Research on Organizational Transformations through Big Data Analytics, ISBN-13: 9781466672727, ISBN-10: 1466672722, EISBN-13: 9781466672734, November 2014.
https://doi.org/10.4018/978-1-4666-7272-7
https://www.igi-global.com/dictionary/solving-solid-transportation-problems-with-multi-choice-cost-and-stochastic-supply-and-demand/43346
[8] Petrakieva S. Automatic solution of transport problems with Excel, 14-th International Confer-ence "Challenges in Higher Education Research in 21-st century", Sozopol, Bulgaria, pp. 46-49, 31 May - 3 June 2016.
FOUR-DIMENSIONAL ENCODING OF CHARACTER SEQUENCES AND EVALUATION OF THEIR SIMILARITIES AND DIFFERENCES
Martin Marinov
Abstract
This paper describes a string encoding algorithm, which produces sparse distributed representations (SDR) of text data. In essence, this is a modified version of a prior algorithm and the modifications have the following benefits:
- the ability to decode data, without loss of information;
- greatly increased capacity of the encoding space;
- the possibility of performing more detailed comparisons of encoded strings.
The main disadvantage compared to the prior algorithm is the increased complexity of the procedure for encoded string comparison. This is due to the use of a four-dimensional encoding space, instead of a two-dimensional space.
Keywords
NLP, languages, text mining, unstructured text, data cleaning, data preparation, sparse data representation, SDR.
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DOI: 10.47978/TUS.2020.70.02.008
References:
[1] Годишник на Технически Университет-София, том 68, книга 2, 2018, http://proceedings.tu-sofia.bg/
[2] M. Marinov, A. Efremov, Representing Character Sequences as Sets: A simple and intuitive string encoding algorithm for NLP data cleaning, 2019 IEEE International Conference on Advanced Scientific Computing (ICASC), Romania, 2019, pp. 1-6.
https://doi.org/10.1109/ICASC48083.2019.8946281
OVERVIEW OF THE METHODS FOR SELF-ORGANIZATION IN SWARM ROBOTICS
Aleksandar Marinchev
Abstract
Self-organization is a common phenomenon observed in many natural and artificial systems. The overall coordinated behavior of the system is due to simple rules for interaction between its components. Thanks to these properties, self-organization plays a key role in swarm robotics, as it allows swarm coordination with minimal com-plexity of individual robots.
This paper reviews the methods and tools for self-organization that are used in swarm robotics or are found in natural systems.
Keywords
self-organization, swarm robotics, distributed systems.
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DOI: 10.47978/TUS.2020.70.02.009
References:
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[7] Song, Y., et al., A novel foraging algorithm for swarm robotics based on virtual pheromones and neural network, Elsevier B.V. Applied Soft Computing Journal, Volume 90, art. 106156, 2020.
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https://doi.org/10.1016/j.jocs.2019.101049
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https://doi.org/10.1016/j.biosystems.2020.104187
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[12] Innocente, M., Grasso, P., Self-organising swarms of firefighting drones: Harnessing the powerof collective intelligence in decentralised multi-robot systems, Elsevier B.V. Journal of Computational Science, Volume 34, pp. 80-101, 2019.
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[14] Nedjah, N., Silva, L., Review of methodologies and tasks in swarm robotics towards standard-ization, Elsevier B.V. Swarm and Evolutionary Computation, Volume 50, art. 100565, 2019.
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SURVEY AND ADJUSTMENT OF CONTROLLER OF A GRAPH-ANALYTICAL METHOD TO A SECOND ORDER OBJECT
Boris Grasiani
Abstract
This paper proposes to adjust the controller using a graph-analytical method in the complex plane. The various configurations regarding the location of zeros and poles to those of the object are also considered. Adjusted controllers are surveyed, such as they are integrated into control systems, and some of the quality indicators of an automatic control system are analyzed.
Keywords
complex plane, control systems, quick response.
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DOI: 10.47978/TUS.2020.70.02.010
References:
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REPETITIVE DRC-SYSTEM OF ROBOT-MANIPULATOR FANUC M-430IA/4FH
Emil Nikolov, Nina G. Nikolova
Abstract
A repetitive ML-DRC-system for an industrial robot manipulator has been proposed and analyzed. The performance and filtering properties of the system to effectively compensate for production mechanical vibrations have been studied. Results of robust analysis in conditions of a priori uncertainty are presented.
Keywords
Repetitive ML-DRC-system, mechanical vibration filtration, robust analysis.
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DOI: 10.47978/TUS.2020.70.02.011
References:
1. Cong Wang, Wenjie Chen, Masayoshi Tomizuka (2012), Robot End-effector Sensing with Position Sensitive Detector and Inertial Sensors, In Proc. of 2012 IEEE International Conference on Robotics and Automation River Centre, Saint Paul, Minnesota, USA, May 14-18, 2012, 978-1-4673-1405-3/12/$31.00 ©2012 IEEE, 5252-5257
https://doi.org/10.1109/ICRA.2012.6225180
2. Masayoshi Tomizuka (2013), Control Methodologies for Manufacturing Applications, Manufacturing Letters, 2013 Elsevier, 1 (2013), 46-48
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3. Shouren Huang, Niklas Bergström, Yuji Yamakawa, Taku Senoo, Masatoshi Ishikawa (2016), High-Performance Robotic Contour Tracking Based on the Dynamic Compensation Concept, In Proc. of 2016 IEEE International Conference on Robotics and Automation (ICRA), 2016 IEEE, Electronic ISBN: 978-1-4673-8026-3, DOI: 10.1109/ICRA.2016.7487577, 3886-3893
https://doi.org/10.1109/ICRA.2016.7487577
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7. E. Nikolov (2019), DRC-Systems - Invers Solutions with Fractional Clegg-Operators - part 1, part 2, Journal Proceedings of Technical University of Sofia, Volume 69, Issue 3, 2019, 2019 Publishing House of Technical University of Sofia, ISSN 1311-0829, pp. 47-66
https://doi.org/10.47978/TUS.2020.70.02.012
8. E. Nikolov, N.G. Nikolova, M. Georgiev (2020), Description and modelling of robot-manipu-lator FANUC M-430iA/4FH, In the 9-th International Scientific Conference "Engineering, Technologies and Systems", Technical University-Sofia Plovdiv Branch, 14-16 May, Plovdiv, Bulgaria
https://doi.org/10.1088/1757-899X/878/1/012006
9. E. Nikolov, V. Karlova-Sergieva, B. Grasiani (2020), Design control system of robot-manipu-lator FANUC M-430iA/4FH, In the 9-th International Scientific Conference "Engineering, Technologies and Systems", Technical University-Sofia Plovdiv Branch, 14-16 May, Plovdiv, Bulgaria
https://doi.org/10.1088/1757-899X/878/1/012007
10. E. Nikolov, N.G. Nikolova (2020), Performance Analysis and Robust Analysis of the DRC-System of Robot-Manipulator FANUC M-430IA/4FH, In Proc. of IEEE International Conference Automatics and Informatics'2020 (ICAI'20), 1-3 October 2020, Varna, Bulgaria
https://doi.org/10.47978/TUS.2020.70.02.011
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12. Nikolova N.G., E. Nikolov (2013), Absorptive Repetitive Filters with Operators of General-ized Fractional Calculus, Journal Cybernetics and Information Technologies, 2013, Volume 12, No X, ISSN 1311-9702, 2013 Bulgarian Academy of Sciences, pp. 21-32
DRC-SYSTEMS - INVERS SOLUTIONS WITH FRACTIONAL CLEGG-OPERATORS - PART 3
Emil Nikolov
Abstract
In this work, are proposed, researched and analyzed structure, methods and algorithms for designing of fractional DRC-systems with ML-Clegg-differentiators. For their development, inverse solutions of the synthesis problem were used with the help of rational fractional ML-Clegg-operators from the theory of generalized fractional calculus. Their potentials advantages are proven. Results of perturbation and robust analysis for numerical example are presented.
Keywords
fractional DRC-systems, ML-Clegg-differentiation filters, perturbation and robust quality analysis.
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DOI: 10.47978/TUS.2020.70.02.012
References:
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[24] Nikolov E. (2019), DRC-Systems - Invers Solutions with Fractional Clegg-Operators - part 1, Journal Proceedings of Technical University of Sofia, Volume 69, Issue 3, 2019, 2019 Pub-lishing House of Technical University of Sofia, ISSN 1311-0829, pp. 57-66