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Extensions to Probabilistic Linear Discriminant Analysis for Speaker Recognition
Plchot, Oldřich ; Fousek, Petr (referee) ; McCree,, Alan (referee) ; Burget, Lukáš (advisor)
Tato práce se zabývá pravděpodobnostními modely pro automatické rozpoznávání řečníka. Podrobně analyzuje zejména pravděpodobnostní lineární diskriminační analýzu (PLDA), která modeluje nízkodimenzionální reprezentace promluv ve formě \acronym{i--vektorů}. Práce navrhuje dvě rozšíření v současnosti požívaného PLDA modelu. Nově navržený PLDA model s plným posteriorním rozložením modeluje neurčitost při generování i--vektorů. Práce také navrhuje nový diskriminativní přístup k trénování systému pro verifikaci řečníka, který je založený na PLDA. Pokud srovnáváme původní PLDA s modelem rozšířeným o modelování neurčitosti i--vektorů, výsledky dosažené s rozšířeným modelem dosahují až 20% relativního zlepšení při testech s krátkými nahrávkami. Pro delší testovací segmenty (více než jedna minuta) je zisk v přesnosti menší, nicméně přesnost nového modelu není nikdy menší než přesnost výchozího systému. Trénovací data jsou ale obvykle dostupná ve formě dostatečně dlouhých segmentů, proto v těchto případech použití nového modelu neposkytuje žádné výhody při trénování. Při trénování může být použit původní PLDA model a jeho rozšířená verze může být využita pro získání skóre v případě, kdy se bude provádět testování na krátkých segmentech řeči. Diskriminativní model je založen na klasifikaci dvojic i--vektorů do dvou tříd představujících oprávněný a neoprávněný soud (target a non-target trial). Funkcionální forma pro získání skóre pro každý pár je odvozena z PLDA a trénování je založeno na logistické regresi, která minimalizuje vzájemnou entropii mezi správným označením všech soudů a pravděpodobnostním označením soudů, které navrhuje systém. Výsledky dosažené s diskriminativně trénovaným klasifikátorem jsou podobné výsledkům generativního PLDA, ale diskriminativní systém prokazuje schopnost produkovat lépe kalibrované skóre. Tato schopnost vede k lepší skutečné přesnosti na neviděné evaluační sadě, což je důležitá vlastnost pro reálné použití.
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Methodology of highly reliable systems design
Straka, Martin ; Gramatová, Elena (referee) ; Racek, Stanislav (referee) ; Kotásek, Zdeněk (advisor)
In the thesis, a methodology alternative to existing methods of digital systems design with increased dependability implemented into FPGA is presented, new features which can be used in the implementation and testing of these systems are demonstrated. The research is based on the use of FPGA partial dynamic reconfiguration for the design of fault tolerant systems. In these applications, the partial dynamic reconfiguration can be used as a mechanism to correct the fault and recover the system after the fault occurrence. First, the general principles of diagnostics, testing and digital systems dependability are presented including a brief description of FPGA components and their architectures. Next, a survey of currently used methods and techniques used for the design and implementation of fault tolerant systems into FPGA is described, especially the methods used for fault detection and localization, their correction, together with the principles of evaluating fault tolerant systems design quality. The most important part of the thesis is seen in the description of the design methodology, implementation and testing of fault tolerant systems implemented into FPGAs which uses SRAMs as the configuration memory. First, the methodology of developing and automated checker components design for digital systems and communication protocols is presented. Then, a reference architecture of a dependable system implemented into FPGA is demonstrated including several fault tolerant architectures based on the use of partial dynamic reconfiguration as the mechanism of fault correction and the recovery from it. The principles of controlling the reconfiguration process are described together with the description of the test platform which allows to test and verify the design of fault tolerant systems based on the methodology presented in the thesis. The experimental results and the contribution of the thesis are discussed in the conclusions.
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Methodology of highly reliable systems design
Straka, Martin ; Kotásek, Zdeněk (advisor)
In the thesis, a methodology alternative to existing methods of digital systems design with increased dependability implemented into FPGA is presented, new features which can be used in the implementation and testing of these systems are demonstrated. The research is based on the use of FPGA partial dynamic reconfiguration for the design of fault tolerant systems. In these applications, the partial dynamic reconfiguration can be used as a mechanism to correct the fault and recover the system after the fault occurrence. First, the general principles of diagnostics, testing and digital systems dependability are presented including a brief description of FPGA components and their architectures. Next, a survey of currently used methods and techniques used for the design and implementation of fault tolerant systems into FPGA is described, especially the methods used for fault detection and localization, their correction, together with the principles of evaluating fault tolerant systems design quality. The most important part of the thesis is seen in the description of the design methodology, implementation and testing of fault tolerant systems implemented into FPGAs which uses SRAMs as the configuration memory. First, the methodology of developing and automated checker components design for digital systems and communication protocols is presented. Then, a reference architecture of a dependable system implemented into FPGA is demonstrated including several fault tolerant architectures based on the use of partial dynamic reconfiguration as the mechanism of fault correction and the recovery from it. The principles of controlling the reconfiguration process are described together with the description of the test platform which allows to test and verify the design of fault tolerant systems based on the methodology presented in the thesis. The experimental results and the contribution of the thesis are discussed in the conclusions.
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Optimization of network flow monitoring
Žádník, Martin ; Lhotka,, Ladislav (referee) ; Matoušek, Radomil (referee) ; Sekanina, Lukáš (advisor)
The thesis deals with optimization of network flow monitoring. Flow-based network traffic processing, that is, processing packets based on some state information associated to the flows which the packets belong to, is a key enabler for a variety of network services and applications. The number of simultaneous flows increases with the growing number of new services and applications. It has become a challenge to keep a state per each flow in a network device processing high speed traffic. A flow table, a structure with flow states, must be stored in a memory hierarchy. The memory closest to the processing is known as a flow cache. Flow cache management plays an important role in terms of its effective utilization, which affects the performance of the whole system. This thesis focuses on an automated design of cache replacement policy optimized to a deployment on particular networks. A genetic algorithm is proposed to automate this process. The genetic algorithm generates and evaluates evolved replacement policies by a simulation on obtained traffic traces. The proposed algorithm is evaluated by designing replacement policies for two variations of the cache management problem. The first variation is an evolution of the replacement policy with an overall low number of state evictions from the flow cache. The second variation represents an evolution of the replacement policy with a low number of evictions belonging to large flows only. Optimized replacement policies for both variations are found while experimenting with various encoding of the replacement policy and genetic operators. The newly evolved replacement policies achieve better results than other tested policies. The evolved replacement policy lowers the overall amount of evictions by ten percent in comparison with the best compared policy. The evolved replacement policy focusing on large flows lowers the amount of their evictions two times. Moreover, no eviction occurs for most of the large flows (over 90%). The evolved replacement policy offers better resilience against flooding the flow cache with large amount of short flows which are typical side effects of scanning or distributed denial of service activities. An extension of the replacement policy is also proposed. The extension complements the replacement policy with an additional information extracted from packet headers. The results show further decrease in the number of evictions when the extension is used.
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The Pump with a Diffuser with Stochastic Blades (Runner and Diffuser)
Dobšáková, Lenka ; Melichar, Jan (referee) ; Veselý, Jindřich (referee) ; Haluza, Miloslav (advisor)
This doctoral thesis studies the non-uniform blade cascade for centrifugal pumps. Influence of non-uniform blade cascade is investigated on the impeller and diffuser. A non-uniform blading impeller of pumps in this doctoral thesis was examined in terms of influence on efficiency characteristic. The idea of using non-uniform blading is to obtain a flat efficiency characteristic. Then the centrifugal pump could be used on larger scale of power with achieving a sufficiently high efficiency. The work is based on experimental measurements and numerical simulations of non-uniform hydraulic pump components. Non-uniform impeller and the diffuser were newly designed for this research. A new measuring track of small submersible pumps was needed to design and build for measurements. Different pump combinations with conventional hydraulics on one working point and hydraulics with non-uniform were measured. All measurements were evaluated and characteristics of efficiency, head and power were obtained for each measured combination. Some of pump combinations (which were measured in experiment) were numerically simulated by program Ansys Fluent. Data needed to evaluate the characteristic of efficiency and specific energy were collected from each numerical simulation. A theoretical consideration concerns the influence of non-uniform blade cascade applied on diffuser. The suggestion how to decrease hydraulic losses in canals was done. The theoretical consideration how to make a flat efficiency characteristic was made.
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The mentor position within in the nursing team, and her the cooperation with the shift nurses.
MAŘÍKOVÁ, Václava
Abstract This diploma thesis deals with the position of nursing mentor and her cooperation with shift nurses. The theoretical part of the thesis is divided into seven chapters, and focuses on the current nursing profession that is also interconnected with education and legislature. The work is further dealing with the role of the nursing mentor and her cooperation with the nursing team. Last but not least, the theoretical part is devoted to the important role of ethics and morality in the nursing profession that is undoubtedly of central importance. We are also addressing the Certified Course for Mentors that we regard as rather positive as one of the forms of lifelong education. The nurses completing the course will acquire new skills and knowledge, but also knowledge in the field of psychology, law, didactics and other fields. The role of a nurse-mentor is rather important as she can pass the acquired knowledge further and positively influence the students in this way over the course of professional training facilitating their adaptation when they start their professional career. It was the main objective of this work to map the current position of a nurse? mentor, what her experience is with cooperation with other shift nurses as part of practical education in the workplace, and whether the nurses direct and sufficiently motivate the students to become interested in the profession of general nurses or midwifes. The section on research employed two methods. The first method consisted in quantitative research in the form of questionnaires. We employed two questionnaires, one targeted the nurses-non-mentors, while the second was intended for nurses-mentors. As a second method, qualitative research was carried out using semi-structured interview conducted with selected head and ward (charge) nurses. Using the qualitative survey approach, we tested the following working hypotheses. H1: the general nurses know what the role of a nurse-mentor is in the health-care team, H2: the nurses-mentors motivate their students to raise their interest in the profession of general nurse, H3: the nurses-mentors are not always occupying leading positions, H4: the nurses-mentors are perceived positively by the shift nurses,
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Právní a zdravotně sociální aspekty činnosti OSPOD jako ustanovených opatrovníků v zámu nezletilých dětí
BORSKÁ, Jana
The Czech Republic as a signatory of the Convention on the Rights of the Child has vested the practice of state administration in the field of care for minor children to municipalities with extended powers, where the protection of the rights and legitimate interests of minor children is safeguarded by state authorities of social and legal protection of children (ASLPC hereinafter). These authorities are incorporated to the extent laid down by the Act on Social and Legal Protection of Children (Act No 359/1999 Coll., as amended). The position and roles of ASLPC and their competence and jurisdiction are also regulated by the same act. The position of workers of these authorities and its legal embodiment is equally important. Regarding professionality, there are high demands on these workers. In the Czech Republic, significant changes in legislature have been made over the past three years. These amendments have led to the strengthening of the rights of minor children and to the establishing of new tools for their protection. In connection with the adoption of new substantive regulation of family law, which is now exhaustively dealt with by the Act No 89/2012 Coll., the Civil Code, new procedural rules have been established regarding protection of rights of minor children. Such procedural legislation includes (apart from the long-existent Act No. 99/1963, the Code of Civil Procedure) the Act No 292/2013 Coll., on Special Civil Proceedings. The decision-making regarding minor children has been vested mainly by the state into the competence of courts. The courts appoint the locally relevant ASLPC as a guardian who then represents the interests of minor children. The purpose, interwoven with and derived from the first one, was to explore the opinions of selected social workers of ASLPC and of district court judges regarding the defined problems occurring during the work of ASLPCs and courts while protecting the interests of minor children. These particularly include: the use of the tool of precautionary measure; problems of different territorial jurisdiction of courts and ASLPCs; processing of complaints regarding bias in various phases of the proceedings; professional training of workers of ASLPC It is evident from the proposals of both judges and ASLPC workers that it is necessary to unify territorial jurisdiction. The courts are suggesting the priority criterion of the address where the child mainly resides. ASLPC workers suggest the official permanent residence as the prime criterion. Bias causes problems in all phases of proceedings. It is obvious that courts take differing approaches towards the solution of this problem (some courts solve the problem of bias complaints filed by the parties while other courts do not) and for ASLPC workers it is difficult to assess how to act when such complaint is raised against them. The training of ASLPC workers - workers are obliged to educate themselves and their employer is obliged to finance such training. Not all ASLPCs are able to provide training in the required extent - due to financial reasons (the average costs of education of one employee pose from 9,169 to 13,400 CZK annually and they cover approximately 6 days of training). The heavy work-load caused by insufficient numbers of ASLPC employees prevents them from completing such compulsory training. As part of the examination of the "participation of a collision guardian in court proceedings" it has been found out that irregular participation of the worker in the proceedings (absence from participation in appeals proceedings); incomplete reports (directed to courts) from surveys in families. Based on comprehensive examination of the problems of territorial jurisdiction, it was recommended that requests are independently recorded and financial compensation is provided for ASLPCs who are requested to represent minors in front of courts, to draft proposals for precautionary measures.
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Are There Any Digital Curators in Czech Libraries?
Římanová, Radka ; Melichar, Marek
The development of digital repositories reveals the need for new Czech terminologies for library positions. One such job title or specialization is “digital curator”, a term which refers to a specialist responsible for digital collections. Competencies for digital curators include technical, organizational, communication, and marketing skills as well as some level of expertise in computer science as well as in information and library science. A survey of several administrators of Czech digital libraries asks how to best professionally label this group of library staff with respect to the actual activities they perform in their jobs - digital curators, administrators of digital libraries, or digital librarians? Job titles have a strong impact on higher education curricula, on the management of libraries, and also on the coordinated system of remuneration of employees at libraries, academic, and research institutions.
Fulltext: idr-1041_3 - PDF; idr-1041_4 - PDF Slides: idr-1041_1 - PDF; idr-1041_2 - PDF Video: idr-1041_5 - MP4
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General Data Protection Regulation and its Impact on Grey Literature
Koščík, Michal
In April 2016, the European commission adopted a new General Data Protection Regulation. This regulation is based on fundamental principles of the existing legislation and elaborates it further into the set of rather detailed legal instructions. The suggested paper aims to summarize the parts of the new regulation that are most relevant for operators of gray literature repositories, who will have to adapt within the next two years. The paper will focus on the issues of consent to the processing of personal data, the legal regime of processing personal data without the consent of the data subjects, the data subject’s right to information as well as the legal regime of acquisition of personal data by third parties and exercise of the newly formulated right to be forgotten.
Fulltext: idr-1039_1 - PDF Slides: idr-1039_2 - PDF; idr-1039_3 - PDF Video: idr-1039_4 - MP4
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Organization and management of production in selected enterprise
DRNOVÁ, Markéta
The topic of my dissertation is "Organization and management of production in selected enterprise". The main goal of this dissertation is mapping of selected enterprise in one year period and obtain sufficient amount of information for future analysis and suggest possible improvements. The identification data, characteristic, products and services and production planning of selected enterprise are provided in introduction of practical part of this dissertation. Analysis of present state with mapping of present state for individually semi-finished products is introduced in the next part of dissertation. For analysis of present state was calculated VA index and for each semi-finished product was created diagram of material movement in next chapter. The goal of analyses and diagram is the finding of narrow spaces in the material flow. The target map of future state was created in the next part. This map is based on present map. The future map presents critical factors that need to be improved. Finally it defines a new VA index, which should be approach to the current state. The penultimate section includes recommendations methods and elements of lean production to the new production hall which the company wants to build. Among the recommended methods are mainly the 5S method, visualization, standardization, SMED and Bottleneck. The last chapter contains a number of measures. For example employee motivation, continuous improvement, personal responsibility, introduction of EDI and ergonomics which would lead to the improvement of the business this enterprise.
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