Geometric representations of linear codes

We say that a linear code C over a field F is triangular representable if there exists a two dimensional simplicial complex $\Delta$ such that C is a punctured code of the kernel ker $\Delta$ of the incidence matrix of $\Delta$ over F and there is a linear mapping between C and ker $\Delta$ which is a bijection and maps minimal codewords to minimal codewords. We show that the linear codes over rationals and over GF(p), where p is a prime, are triangular representable. In the case of finite fields, we show that this representation determines the weight enumerator of C. We present one application of this result to the partition function of the Potts model. On the other hand, we show that there exist linear codes over any field different from rationals and GF(p), p prime, that are not triangular representable. We show that every construction of triangular representation fails on a very weak condition that a linear code and its triangular representation have to have the same dimension.Comment: 20 pages, 8 figures, v3 major change

Geometric representation of binary codes and computation of weight enumerators

For every linear binary code $C$, we construct a geometric triangular configuration $\Delta$ so that the weight enumerator of $C$ is obtained by a simple formula from the weight enumerator of the cycle space of $\Delta$. The triangular configuration $\Delta$ thus provides a geometric representation of $C$ which carries its weight enumerator. This is the initial step in the suggestion by M. Loebl, to extend the theory of Pfaffian orientations from graphs to general linear binary codes. Then we carry out also the second step by constructing, for every triangular configuration $\Delta$, a triangular configuration $\Delta'$ and a bijection between the cycle space of $\Delta$ and the set of the perfect matchings of $\Delta'$.Comment: 16 pages, 11 figures, submitted to Advances in Applied Mathematics, v2: major conceptual change

Production and processing of tubes

Práce se zabývá rozborem jednotlivých metod využívaných při výrobě bezešvých a švových ocelových trubek. Jedná se o literární studii, která popisuje podstatu jednotlivých přístupů výroby, jejich srovnání a použití na domácím trhu. Konkrétně popisuje bezešvé trubky produkované odstředivým litím a metodou tváření, jež je dále dělí na válcování, protahování, lisování a tažení, a švové, vyráběné z plechů a pásů, které jsou zformovány do tvaru trubky a svařeny příslušnou metodou spadající pod kategorii tavného nebo tlakového svařování.This thesis presents the analysis of individual methods used in the production of seamless and seam steel pipes. It is a literature review that describes the essence of individual approaches to production, their comparison and use in the domestic market. In particular, it describes seamless tubes produced by centrifugal casting and a forming method which further divides them into rolling, pressing and drawing, and seams, made of sheets and strips, which are formed into a tube shape and welded by an appropriate method falling under the category of fusion or pressure welding.

Design of automatic lawnmower

Diplomová práce komplexně řeší design automatické sekačky na trávu. Inovativní koncept respektuje všechny technické, ergonomické, estetické a ekologické požadavky na něj kladené. Popisu samotného tvůrčího designérského procesu, tedy vývoji designu od variantních studií až k finálnímu řešení, předchází rešeršní část představující vývojovou, technickou a designérskou analýzu tématu. Závěr práce se zabývá rozborem navrženého designérského řešení, jeho charakterem, přínosem společnosti a především konkrétní rolí průmyslového designu v návrhu automatické travní sekačky.The aim of this diploma thesis is the design of an automatic lawn mower. The design solution is based on innovative concept respecting all technical, ergonomical, aesthetical and ecological demands. A research study, including a historical, technical and design analysis of lawn mower, is preceding the description of main creative part of design process starting from the concept development and ending up with the final solution. A conclusion of the thesis presents an analysis of final solution, its character, contribution to the human society and the particular role of industial design in automatic lawn mower concept.

Rational Unified Process as Methodology of Software Development

Cílem této práce je seznámit se s procesem vývoje softwaru dle vybraných metodik s hlavním zaměřením na metodiku Rational Unified Process od firmy IBM. Incepční a elaborační fáze této metody také aplikuji na praktickém  příkladě.Goal of my work is to introduce software development process metods specialized to Rational Unified Process metod from IBM. I aplicate inception and elaboration phases of RUP on practical example.

Possibilities of the graphical analysis of categorical data

The goal of my work was described the possibilities of the graphical analysis of categorical data. The first part is about clarifying the concept of categorical data and the rules of charting; the second part about the column and the pie chart, which are used most frequently. The last part presents graphical displays which often have variety properties and they are not used in normal commercial statistical programs. For example they allow a visual test of the hypothesis of independence. These are fourfold displays, sieve diagram, trilinear plot and mosaic display

Why Do the Poker Players Deal More Often on High Stakes Than on Low Stakes Tournaments? Poker Deals Case.

This thesis aplied tools of economic analysis on situation in poker, where players choose to finish tournament or make a deal and take certain amount of money immediately. Theoretical frame consists of economic theories for decesion under risk and poker literature. Hypotheses are tested with regresion analysis on dataset which I obtain by my own observing. Estimations support hypothesis that players are risk-averze and loss-averze. In bigger tournaments are bigger prizepools and that is the reason, why players in bigger tournament make deals more often. Moreover deal is more likely, when players are approximetly equal skilled in poker

Vliv teploty na schopnost oplození a líhnivosti při krátkodobém skladování neoplozených jiker síha peledě (Coregonus peled)

The northern whitefish Coregonus peled (Gmelin, 1788), originally from Russia, was introduced to the Czech Republic in 1970 for its tasty meat and good growth ability. Breeding of this species has been very popular in the past. Currently, thanks to the fish-eating predators, traditional breeding of this species is on decline. The aim of this M. Sc. Thesis was to sumarize the avaible information in the field of peled biology, artificial propagation and also information about effect of temperature on the ability of fertilization and hatching for short-term of unfertilized eggs in other salmonid species. In the practical part, the influence of temperature and length of storage of stripped, unfertilized eggs of peled on fertilization, survival to eyed eggs and hatching were observed. Unfertilized eggs were divided into five bowls and deposited in thermo boxes, which were tempered to 2.5, 5, 7.5, 10 and 12.5 °C. After time intervals of 1, 4, 12, 24, 36, 48, 60 and 72 hours, approximately 100 - 200 eggs were taken from each thermobox, which were fertilized with fresh sperm (collected from several males) and water from the hatchery. The fertilized and purified eggs were moved to the incubators with continuously inflow of fresh water. Dead eggs were removed and recorded. Subsequently, fertilization, eyed eggs and hatching eggs were determined. The resulting values of these parameters were expressed as a percentage of the total number of used eggs. High levels of fertilization and survival to eyed eggs were achieved when stored within 1 day from eggs stripping at all temperatures except the highest temperature of 12.5 ° C. As the interval gradually lengthened, the fertilization and survival parameters also decreased, most notably at 7.5 and 10 ° C. To obtain the largest possible amount of fry in fishing practice, it is recommended to store eggs at 2.5 and 5 ° C, up to 48 hours after ova stripping. At higher temperatures, the effective storage time is reduced to 12 hours. Storing eggs for longer than 48 hours, in practical terms has no meaning. At the same time, it was found that at the above-mentioned optimal temperatures for storing eggs (2.5 and 5 ° C), the best hatching results were obtained when storing stripped eggs for 12 hours. Not only for longer, but also for shorter storage lengths, the values of this parameter were lower

Removal of selected metals from waste water using a hybrid membrane proces

Tato diplomová práce se zabývá odstraňováním těžkých kovů z vody pomocí hybridního membránového procesu. Tento proces kombinoval sorpci na zeolitu s cross-flow mikrofiltrací na keramické membráně. Teoretická část práce popisuje druhy odpadních vod a metody čištění vod. Největší prostor je zde věnován membránovým procesům. Experimentální část následně popisuje ověření účinnost procesů při odstraňování vybraných těžkých kovů (Cd2+, Ni2+, Cu2+) z vody s použitím zeolitu A a kombinace sorpčního procesu a mikrofiltrace. Naměřená a vyhodnocená data pak popisují jak kinetiku procesů, tak i stanovenou sorpční kapacitu.This thesis is concerned with removing heavy metals from water using hybrid membrane process. This process combined sorption on zeolite and a cross-flow microfiltration on a ceramic membrane. The theoretical part describes types of wastewater and water treatment methods. the most important attention is devoted to the membrane process. Results of experiments verify the efficiency of processes of selected heavy metal removing (Cd2 +, Ni2 +, Cu2 +) from water using zeolite A, and the zeololite sorption and microfiltration combination. Measured and processed data describe both the kinetics of the processes as well as sorption capacity evaluation.Fakulta chemicko-technologick