|
Electron beam cutting of non-metals
Dupák, Libor
Various materials are difficult to cut or drill, e.g. due to their mechanical properties (hardness, fragility). Also, sometimes the required hole shape and dimensions may be difficult to obtain by mechanical machining or the efficiency of such process is low. Electron beam machining is one way to overcome these issue. It is based on the melting and evaporation of the material by the intense electron beam. The presented experiments were performed on the desktop electron beam welder MEBW-60/2, developed at the Institute of Scientific Instruments AS CR, v.v.i. at Brno. It is also manufactured and sold by the Focus GmbH company under licence. In the following experiments, several sets of grooves were prepared, both in quartz glass and AI2O3 ceramics, to find out the influence of various beam parameters on groove dimensions. The experimental conditions were as follows: acceleration voltage 50 kV, beam current 0.1-1 mA, machining speed 2.5-50 mnvs'1.
|
|
Systém odměňování v malém IT podniku
Novotný, Lukáš ; Dvořáková, Zuzana (advisor) ; Cetkovský, Pavel (referee)
The topic of this thesis is reward management and its application in a small-sized IT enterprise. Its goals are to properly document and describe current reward system in the company, evaluate the system and recommend improvements for the system. The first two goals are reached via thorough research of the company through semi-structured interviews, employee satisfaction survey, participant observation and document examination and the last one by applying principles from the current literature and education to the results of the two previous goals. The findings are that the reward system, despite growing organically instead of designed, is relatively effective in some areas, but needs improvement in other areas. The main improvement areas are motivation by contingent pay, communication management and performance management. Relatively well working rewards are especially non-financial reward connected to the work environment and work itself.
|
|
Analysis of the decision-making factors in freight forwarder selection process
Šrámková, Eva ; Novák, Radek (advisor) ; Cempírek, Václav (referee) ; Průša, Bohumil (referee)
The thesis analyses the factors of customer decision-making process by choosing a freight forwarder in the Czech Republic market. While applying factors by other relevant research studies dealing with the decision-making process of customers in non-European countries, the research examines factors characteristic for the Czech customers. Questionnaires and in-depth interviews as research methods are applied. Within the research, a new service quality instrument TARRQUAL was developed. The TARRQUAL was proved on a survey including 250 customers of freight forwarder Kühne+Nagel Czech Republic. As service quality measurement, TARRQUAL is supposed to be applied particularly in logistics business field. The project aims at providing input for empirical research in the field of service quality in container shipping, which is lacking in the Central and East European countries.
|
|
STRAIN ENGINEERING OF THE ELECTRONIC STRUCTURE OF 2D MATERIALS
del Corro, Elena ; Peňa-Alvarez, M. ; Morales-García, A. ; Bouša, Milan ; Řáhová, Jaroslava ; Kavan, Ladislav ; Kalbáč, Martin ; Frank, Otakar
The research on graphene has attracted much attention since its first successful preparation in 2004. It possesses many unique properties, such as an extreme stiffness and strength, high electron mobility, ballistic transport even at room temperature, superior thermal conductivity and many others. The affection for graphene was followed swiftly by a keen interest in other two dimensional materials like transition metal dichalcogenides. As has been predicted and in part proven experimentally, the electronic properties of these materials can be modified by various means. The most common ones include covalent or non-covalent chemistry, electrochemical, gate or atomic doping, or quantum confinement. None of these methods has proven universal enough in terms of the devices' characteristics or scalability. However, another approach is known mechanical strain/stress, but experiments in that direction are scarce, in spite of their high promises.\nThe primary challenge consists in the understanding of the mechanical properties of 2D materials and in the ability to quantify the lattice deformation. Several techniques can be then used to apply strain to the specimens and thus to induce changes in their electronic structure. We will review their basic concepts and some of the examples so far documented experimentally and/or theoretically.
|
|
Intuition in creative process of animation movie
Nováčková, Jana Kristýna ; DĚCKÁ, Eliška (advisor) ; ČIHAŘOVÁ, Libuše (referee)
This work deals with the relation of emotions to contemporary experimental animation. It engages in the emotional experience of a viewer to non-narrative film storytelling and its means of expression.
At the same time, it examines what the creative processes and attitudes of filmmakers towards emotions in experimental animation are. Analysis of the questionnaires also reveals whether the creator counts on the viewer's specific interpretation of the film.
|
| |
|
Therapeutic hypotermia after cardiac arrest
JIRCOVÁ, Danuše
The bachelor thesis deals with the influence of a mild therapeutic hypothermia as a hospital post-resuscitation care of patients after cardiopulmonary resuscitation for non-traumatic cardiac arrest. Therapeutic hypothermia is a relatively new method. It is part of the European Guidelines for resuscitation since 2005. It was reported its positive effects on the neurological status of the patients. Using the method reduces the damage to the brain and cardiac muscle. The theoretical part of the thesis deals with the effect of mild hypothermia on the human body. Specifies the indication and contraindication criteria for initiation of therapeutic hypothermia, describes cooling methods of the patient and ways to terminate the therapeutic hypothermia. Describes the monitoring of physiological functions and nursing care of patients. The practical part of bachelor thesis mapped the procedures used in the administration of therapeutic hypothermia in patients treated in two large hospitals. These were Fakultní nemocnice Kralovske Vinohrady in Prague and Nemocnice Ceske Budejovice, a.s. The applied strategy of the research was qualitative. Content analysis of 10 case reports were carried out, 5 case reports from each hospital. Case reports concerning patients after cardiopulmonary resuscitation, who were treated using the therapeutic hypothermia as a part of hospital care. The aim of this thesis was to map the procedures used in the therapeutic hypothermia administration in patients after cardiopulmonary resuscitation. It was made available by hospitals after approval by ethics committees on the basis of applications submitted. The information was subsequently created into case studies that were analysed in the categorization tables. In the discussion, the results were compared with the published knowledge provided in the theoretical part of the thesis, and were commented. Analysed were: the composition of the group of patients by age and gender, provide the basic life support by witnesses prior to arrival of crew of the emergency medical service on scene, initial ECG rhythm after emergency medical service arrival, the time elapsed since the cardiac arrest appeared to restore of spontaneous circulation, initiation of therapeutic hypothermia in pre-hospital care, time elapsed since the therapeutic hypothermia start up to reaching the target body temperature, duration of the therapeutic hypothermia, the methods used for cooling the patients, the methods used for measuring the body temperature and neurological status at the time of discharge or transfer from the hospital. The results of the research surprisingly showed that general public are well-informed. Witnesses were able to recognize cardiac arrest, early called in professional help and were willing to give heart massage. This shows also the success in implementing the method of medical dispatcher-assisted basic life support in practice, because the witnesses were in many cases instructed by the medical dispatchers to resuscitate the patient. The majority of patient's initial ECG rhythm were diagnosed as ventricular fibrillation. Time to restoration of spontaneous circulation in most cases ranged within 29 minutes. To achieve the target body temperature at the recommended time limit has managed to half of patients. Target body temperature was always kept within the recommended timeframe and core body temperature was monitored. Concerns raised by an absence of the method start up in pre-hospital emergency care. The thesis highlighted the seriousness of sudden cardiac arrest and the high incidence of patients dismissed from the department with severe neurological deficit. Therefore, it is necessary to continue in research of this method, improve it and try to incorporate it already to pre-hospital care.
|
|
Effect of snowpack on runoff generation during rain on snow event.
Juras, Roman ; Máca, Petr (advisor) ; Ladislav , Ladislav (referee)
During a winter season, when snow covers the watershed, the frequency of rain-on-snow (ROS) events is still raising. ROS can cause severe natural hazards like floods or wet avalanches. Prediction of ROS effects is linked to better understanding of snowpack runoff dynamics and its composition. Deploying rainfall simulation together with hydrological tracers was tested as a convenient tool for this purpose. Overall 18 sprinkling experiments were conducted on snow featuring different initial conditions in mountainous regions over middle and western Europe.
Dye tracer brilliant blue (FCF) was used for flow regime determination, because it enables to visualise preferential paths and layers interface. Snowpack runoff composition was assessed by hydrograph separation method, which provided appropriate results with acceptable uncertainty. It was not possible to use concurrently these two techniques because of technical reasons, however it would extend our gained knowledge. Snowmelt water amount in the snowpack runoff was estimated by energy balance (EB) equation, which is very efficient but quality inputs demanding. This was also the reason, why EB was deployed within only single experiment.
Timing of snowpack runoff onset decrease mainly with the rain intensity. Initial snowpack properties like bulk density or wetness are less important for time of runoff generation compared to the rain intensity. On the other het when same rain intensity was applied, non-ripe snowpack featuring less bulk density created runoff faster than the ripe snowpack featuring higher bulk density. Snowpack runoff magnitude mainly depends on the snowpack initial saturation. Ripe snowpack with higher saturation enabled to generate higher cumulative runoff where contributed by max 50 %. In contrary, rainwater travelled through the non-ripe snowpack relatively fast and contributed runoff by approx. 80 %.
Runoff prediction was tested by deploying Richards equation included in SNOWPACK model. The model was modified using a dual-domain approach to better simulate snowpack runoff under preferential flow conditions. Presented approach demonstrated an improvement in all simulated aspects compared to the more traditional method when only matrix flow is considered.
|
|
Design of Experiment for Non-Stationary Processes of Production
Jadrná, Monika ; Macák, Tomáš (advisor)
The doctoral thesis is concerned with the services sector and the area of mass production. Particularly, the optimization of the product portfolio of the travel agency and the optimization of production rounds of ammunition.
The theoretical part deals with the current overview of discussed topic. Further, the terminology and methods of the decision-making process are defined to support decision making. The theoretical basis of research focused on the choice of appropriate input variables in the area of services, and on the choice of a particular material option in the production area and appropriate equipment for the production. The theoretical part forms the basis for the practical part of the thesis.
For the doctoral thesis was chosen an enterprise operating in the defined sector. Product portfolio for the services sector is optimised using Fuzzy logic and Fuzzy sets so that the enterprise can maintain its competitiveness in todays highly ambitious market. Product portfolio for manufacture is optimised for achieving desired properties of the product.
The main aim of the thesis is to propose a new methodological approach for the management of selected business processes in their nonstationary time course. The aim of the practical implementation is to verify the functionality of the proposed methodological approach, both in the area of services and in the field of mass production.
|
|
Population genetic analysis of Old Kladruber horse
Vostrá Vydrová, Hana ; Majzlík, Ivan (advisor) ; Karel, Karel (referee)
The Old Kladruber horse, along with the Lipizzaner horse, Andalusian horse and Lusitano horse, is of the original Italo-Spanish type. The Old Kladruber horse is kept in two colour varieties (grey and black). Because the population is closed, there is a concern about the loss of genetic variation. The genetic diversity and population structure were analysed in the Old Kladruber horse breed based on the pedigree information of animals that were registered in the Studbook to identify factors that may have affected the genetic variability of the breed. Pedigree records collected from 1729 to 2013 contained information on 7971 animals that were used in the analyses. The pedigree depth was up to 33 generations, with an average of 15.1 complete generations. The effective number of founders and ancestors contributing to the current genetic pool was 92.69 and 17.16, respectively. The average values of the inbreeding coefficient were as follows: 13% (with a maximum value of 29%) for the reference population (individuals that can currently take part in reproduction, n=612), 11% for the grey variety (with a maximum value of 25%) and 15% for the black variety (with a maximum value of 29%). The proportion of inbred animals was high (99%). The average rate of inbreeding in the reference population was 1%: 0.8% for the grey variety and 1.1% for the black variety, and the respective estimates of the effective population sizes were 52 for the reference population, 62 for the grey variety and 45 for the black variety. The estimated percentage of genetic diversity lost due to non-random mating within subpopulations and the reference population was 1.0, 1.0 and 1.2%, respectively. The total loss of genetic diversity in the reference population, in the grey variety and in the black variety was 11%, 13% and 17%, respectively.
|
guest ::
