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Computer modelling in programming language COMSOL Multiphysics
MÁCHA, Václav
The thesis deals with a computer modelling by means of the commercial software COMSOL Multiphysics. The thesis is structured into three topical sections. The first part is dedicated to the programme characteristics and its development. In the second part the brief characteristics of working with the programme COMSOL Multiphysics is presented which should make the user´s first steps in working with software easier. The last part of thesis shows the specific demonstration of the created multiple physics task taken from the field of plasma physics. This task is solved by means of continuous simulation of a computer modelling based on the drift-diffusion approximation of low temperature plasma. The proposal of the paper for the proceedings of the conference ,,Technical Computing Prague 2012" is also a part of this thesis.
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Generation of random numbers and statistical distributions
BÜRGER, Tomáš
This project contains total of 62 pages, in which are explained basic terms of probability theory and mathematical statistic. This part is followed by explanation of computer modeling and Monte Carlo modeling, in which are shown basic techniques and solutions of the problem by this method. In conclusion of this project is shown an example on maxwell{\crq}s and nonmaxwell{\crq}s allocation of speeds, which has been programmed in program MATLAB.
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New techniques of modeling in adaptive CAD systems
Leicher, Michal ; Vetiška, Vojtěch (referee) ; Huzlík, Rostislav (advisor)
This thesis is aimed at the modern adaptive CAD system possibilities of drawing in The Invetor Studio. The first part of the thesis involves the evaluation and description of the modern adaptive CAD systems. The next part deals with Autodesk Inventor 2011 news. It summarizes advantages of Autodesk Inventor 2011 contrary to its previous editions. The last chapter contains drawing possibilities and creation of the simple electric machine in the Autodesk Inventor 2011.
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Advanced techniques of computer modelling in low- and high-temperature plasma physics
Pekárek, Zdeněk ; Hrach, Rudolf (advisor) ; Kudrna, Pavel (referee) ; Hron, Jaroslav (referee)
This thesis identifies the obstacles in efficient modelling of interaction of plasma and solid surfaces. It presents an enhanced method of solving the Poisson equation optimized to meet the requirements of the Particle-in-Cell modelling approach. A number of applications are discussed, including models of the plasma-facing wall of the nuclear fusion device, tokamak, and its interaction with particle fluxes driven by the intrinsic magnetic field. Another area of applications covers the modelling of plasma probes deployed to diagnose properties of plasma in various experiments. The thesis also includes the computer library code and instructions enabling a rapid use of the Poisson solver method in a third party computer code which implements the PIC approach in a compatible manner.
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Evaluating and modeling of fouling process in heat exchanger
Čirka, Martin ; Kilkovský, Bohuslav (referee) ; Jegla, Zdeněk (advisor)
This diploma thesis discusses fouling processes and mechanisms of industrial heat exchangers, with focus on shell side fouling of heat transfer area by flue gases, and eventually taking fouling into account, or more precisely its modeling and predicting by calculation. Thermal-hydraulic design of heat exchanger is focused mainly on shell side, as flue gases are dominant process medium in terms of fouling and heat transfer. Based on available operational data of evaluated industrial heat exchanger, specific process has been developed to determine by calculation, or more precisely predict change of fouling factor throughout operational period of heat exchanger. Usage and various options of this specific calculation technique are being discussed in conclusion, whether there is a potential to use this technique regarding more complex operational inputs or prediction of fouling process for different operational regime of heat exchanger.
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Operational Risk: Scenario analysis
Rippel, Milan ; Teplý, Petr (advisor) ; Mejstřík, Michal (referee)
Operational risk management and measurement has been paid an increasing attention in recent years - namely due to the Basel II requirements that were to be complied with by all international active financial institutions by January 2008 and also due to recent severe operational risk loss events. This diploma thesis focuses on operational risk measurement techniques and on regulatory capital estimation methods. A data sample of operational losses provided by a Central European bank is analyzed using several approaches. Multiple statistical concepts for the Loss Distribution Approach are considered. One of the methods used for operational risk management is a scenario analysis. Under this method custom plausible loss events defined in a particular scenario are merged with the original data sample and their impact on capital estimates and on the financial institution as a whole is evaluated. Two main problems are assessed in this diploma thesis - what is the most appropriate statistical method to measure and model operational loss data distribution and what is the impact of hypothetical plausible events on the financial institution. The g&h distribution was evaluated to be the most suitable one for operational risk modeling because its results are consistent even while using scenario analysis method. The...
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Modelling the human approach to world
Sigmund, Tomáš ; Toman, Prokop (advisor) ; Řepa, Václav (referee) ; Havel, Ivan M (referee)
The work "Modelling the human approach to world" is part of the mutlidisciplinary field of informatics which deals with production and use of information systems in enterprises and other communities. It contributes to its development in the area of human-machine relationship and communicating information. At present information systems (IS) are used for collecting, distributing, storing, processing and conveying information. Their components are hardware (machines) and software. Without information systems today's work with information wouldn't be possible. People remain in spite of intensive implementation of information technologies the main element for companies' operation. Information technologies help man, cannot replace him however. To understand the role of information technologies it is important to be aware of the difference between man and machine (computer) information processing from which we can deduce the implications for business operation. The computer is only able to work with a reality model prepared by a human being. Reality is in information systems represented by means of signs. Even though we can understand the information system as a tool similar to classical tools (typing machine, filing cabinet etc.), there is a difference, because these tools don't exist as physical objects, but only as signs. The symbolic nature of information systems didn't interest researchers in the past very much, but now it increases. The first reason can be found in the massive implementation of information and communication technologies (ICT), which calls for intelligibility of their representation; the second reason can be found in the fact that computers are used as media with functions similar to textbooks, letters, newspapers, telephones, films, where the importance of semiotics has already been recognized. The advancement of hardware requires from software developers abilities similar to professional artists. The third reason lies in the fact that production processes are more and more controlled by computers. Cooperating people must rely on symbols mediated by computers (Andersen, 1997). IS are more complex and important is their influence on people on many levels and through many means. Structuralism may be of some help as it studied similar phenomena in the first half of the 20th century. In the first part of my work I described the differences between human and computer information processing, in the second part I analysed the modelling theories which take into account the human approach and at the end I deduced general conclusions for the relationship between man and computer in information system and suggested some recommendations on how to improve their relationship and make human understanding and use of information in information system easier. One of the researchers who studied the difference between man and machine was Hubert Dreyfus. He came to the conclusion that there is a principle difference between man and machine. He identified some typical situations where man and machine differ: Rule following, bodily existence, situations, pattern recognition etc. Dreyfus' analysis will be supplemented with the analysis of public space, intentionality and language. I don't want to present a complete description of human approach to world, I rather sketch some key points to clarify the difference between man and machine. From the analysis of man and machine two conclusions emerge: on the one hand proposal how to analyse and propose information system which would better connect subjective and objective aspects; on the other hand importance of IS integration into the business culture and the whole context of human work. As a suitable approach appears in compliance with P. Ricoeur structuralism and its analysis of narrativity. In the area of IS development there are four so called socio-technical theories which try to incorporate some principles of human approach to world into their modelling procedures and balance the superiority of technical view on the human computer interaction. The main common feature of these theories lies in the emphasis on the importance of human factor for organisations (they consider organisations social systems). The role of technical equipment is seen in the support of human activities. They are called Language Action Perspective, specifically methodology DEMO, Organisational Semiotics, Theory of Organised Activity and Human Interaction Management. DEMO methodology focuses on communication which is analysed by means of four axioms based on the language act theory. The theory differentiates between locution, illocution and perlocution. Locution deals with the proposition's content, illocution is related to the intention which we communicate the proposition with and perlocution contains effects in the addressee. From these three perspectives production and communication acts are analysed. Organizational semiotics deals with the semiotic aspect of human communication. It uses a six-stage semiotic ladder with physical, empirical, syntactic, semantic, pragmatic and social level. On all these levels communication and its signs are analysed. On the first three levels machines can be used, on the next three levels the human work with information is carried out and machines don't help there much. Organisational semiotics emphasizes the social level where organisational, social and cultural norms play an important role. Theory of organized activity is based on the theory of units which the group has in common. The theory divides the world on actors and things. For the activity to start both these elements must be present. Typical features of actors are interest and responsibility. The human interaction management tries to modify the proposal and functioning of information systems in order to respect the principles of human work. The basic argument of human interaction management is that most processes where people are involved is in instant change which cannot be governed by rules independent of the process participants. Flexibility is necessary for success. K.H. Broninski, the author of Management of Human Interaction, calls for support for mental work a transformation of information into knowledge. He proposes a procedure structuring work. It consist of five parts: research, evaluation, analysis, constrain, task. Another piece of knowledge of the Human interaction management is that a big proportion of human work has small concrete results, and cannot be quantified. However time spent on researching, comparing, evaluating, generally information processing and their transformation into knowledge, is a substantial part of a worker cooperating with colleagues and other people. It is better for employees to have supportive rather than directive leadership, as people are individuals. People do things in different times, in different ways, on the basis of communication with others, according to the state of resources and their mood. They do what they consider most appropriate in given situation. Continual process change must be possible and it is necessary to support it. Human activities are creative, exploratory and loosely structured. The socio-technical theories neither explicitly address the difference between man and machine nor try to unify their perspectives organically. However they show some content elements which are important for human beings. When considering the human approach to world we cannot be limited to a set of perceptions where man and machine differ. We should consider their arrangement which allows for new ways of understanding reality. The synthesis of the elements can be carried out only when the elements are linked together into a structure, e.g. a plot. Another problem lies in the necessity to consider time. Progressive development and its modalities constitute integral part of a homogenous stylistic form. Two rationalities are at work here; the one understands the world in its unity mediated by a form, best of all and most generally by a narrative; the other systemizes the first understanding and transforms it onto a syntactic level. The modelling techniques use the second syntactic rationality; we can reach it only in time, however. Stories have many advantages in comparison to other ways of conveying information: aims, causes, chances, agents are unified in time and space into a plot. Originally different elements are unified in the plot. They seem accidental; however they gain necessity in the plot. Other important aspects are source of information, narrator, rhythm, repetition and focalization. These elements can be separated on three levels: text, plot, fabula. They concentrate on different elements and their relations. We will use the results of work of the structuralist J. Greimas and his theory of actants suggesting which role can be considered in narrative information conveying. His semiotic square is a method of understanding context elements. Analysis of the elements of narrative which are the results of structuralist research cannot substitute the narrative understanding; we can only approximate it and explain it in further details. We encounter a creative act which cannot be reduced on rules and formalized. That is why a creative approach of the author is necessary in the development of IS. The conclusion achieved in the analysis of differences between human and machine that human understanding and behaviour is not completely formalizable was found in our attempt to use the structuralist approach on design and functioning of information systems. The interconnection of objective world of machines with the subjective human understanding is possible in a story created by a creative human being able to ensure organic and natural unity.
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Joint Learning of Syntax and Semantics
Ercegovcevic, Milos ; Bojar, Ondřej (advisor) ; Mareček, David (referee)
This master thesis addresses the problem of learning varying levels of abstraction of linguistic knowledge. The main focus is on learning latent semantic information as represented by frame classes, verb classes and role fillers by exploring recent successes in Bayesian modeling with hidden variables. Furthermore, close coupling of syntax and semantics is captured in the joint model which also incorporates valuable lexical information. The result is a language-independent, feature-less model of semantic information with a performance comparable to the current state of the art.
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Structure-modelling studies of the haloalkane dehalogenase LinB
ŘEŽÁBEK, Josef
The main aim of this bachelor thesis was structure-dynamics study of LinB86 mutant variant protein isolated from the soil bacterium Sphingobium japonicum UT26. Standard and advanced protein crystallization techniques, basis of solving protein structures from diffraction data and study of enzyme structure and dynamics with the use of standard SW for molecular modelling were applied.
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Petrobras Planning Domain: PDDL Modeling and Solving
Hanes, Martin ; Toropila, Daniel (advisor) ; Gemrot, Jakub (referee)
The thesis explores Petrobras domain from the challenge track of the ICKEPS 2012 competition, which is an example of a difficult problem stand- ing on the borderline between planning and scheduling. It describes state-of-art techniques of the modern artificial intelligence that were chosen for this purpose. It guides the reader in the process of modeling the Petrobras domain in PDDL language and explains the results provided by the existing tools used within plan- ning community. In the end it compares the results of the chosen approach to the other approaches used in ICKEPS 2012 competition, showing that the existing sequential planning systems are usable only for solving smaller problem instances of this domain.
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