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The agricultural drought monitoring and its users and correspondents
Bartošová, Lenka ; Trnka, Miroslav ; Semerádová, Daniela ; Hlavinka, Petr ; Štěpánek, Petr ; Zahradníček, Pavel ; Žalud, Z.
Drought monitoring in the Czech Republic is a key element in climate monitoring. The aim of this article is to describe the possible participation of agronomists, foresters and fruiterers in drought monitoring within the Integrated Drought Monitoring System. This system monitor drought occurence weekly on the base of various information (data from model SoiClim or outputs from satellite Aqua and Terra). One of the main pillar of the monitor is also information about drought impact on yields in the cooperation with especially farmers. Their expert assessment brings insight into actual situation in agricultural landscape in weekly time step. All results are free to download in www.intersucho.cz.
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Proposal of Development of Marketing Communication of Graphic Studio
Štěpánek, Petr ; Hašek, Petr (referee) ; Zich, Robert (advisor)
This bachelors thesis tells about marketing communication development of a graphic design studio. The first section describes the species of communication and tools of the marketing mix. In the following section of analysis, I try to analyze the current state of marketing communication in this graphic design studio and in the last section I create a proposal of a solution, which would lead to its development.
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Design of Load Bearing Concrete Structure
Tuchyňová, Andrea ; Šimůnek, Petr (referee) ; Štěpánek, Petr (advisor)
This diploma thesis is dealing with frame multi-storey garage structure, mainly with its slab. According to the assignment there was made a parametrical study. It contains the comparision of three construction versions: solid slab, slab with void formers Cobiax and prestressed concrete slab. At the chosen variant the 3D mathematical model, which was created in software Scia Engineer, was specified and the construction was designed according to ultimate limit state and serviceability limit state. The outlet of this thesis is structural design and drawings with all designed items
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Design of concrete structures with FRP reinforcement
Januš, Ondřej ; Girgle, František (referee) ; Štěpánek, Petr (advisor)
The diploma thesis presents design of construction with FRP reinforcement. Including design process of cross-section with FRP reinforcement exposed to bending moment and shear force at ultimate limite state according to given standards and guidelines. Long term physical and mechanical properties of FRPs are taking into account. There are also compared load capacities of cross-section exposed to combination of bending moment and axial force, which were designed according to mentioned standards. In another part of diploma thesis there is a design of construction (precast gatehouse) with FRP reinforcement and steel reinforcement with ordinary and lightweight concerete.
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Kotvení předpjaté frp výztuže pro betonové konstrukce
Girgle, František ; Horák, David ; Štěpánek, Petr ; Laníková, Ivana ; Šimůnek, Petr
Non-metallic reinforcement has many advantages, but there are some areas of application that need to be resolved to improve the usage of FRP reinforcement in real conditions. One of the disadvantages of FRP reinforcement is its lower modulus of elasticity, which leads to greater deflections of structures and can also cause early propagation of cracks. The paper deals with the possibility of eliminating this problem by prestressing the reinforcement. It covers several problems related to anchoring and current anchoring methods used world-wide. The paper also mentions some drawbacks of these methods. In an effort to bypass these drawbacks a new anchoring method has been developed. It differs in the way longitudinal forces are transferred from the bar to the surrounding concrete. Basically, it is based on the addition of an additional anchoring member (cylinder) on the surface. This member is made of polymers so the whole system remains completely steel-free and very simple to produce. Before using the system in real structures a series of tests were performed and the results are presented. Also, some prestressed test panels were prepared and compared with standard panels.
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Influence of standards changing on reliability of lightweight roof structures
Štěpánek, Petr ; Girgle, František ; Daněk, Petr ; Růžičková, Jana
This paper is intended to experts who work on the expert opinion for faults and breakdowns of lightweight roof load bearing structures. Changes of loading standards during the time play a fundamental role by redesigning of existing roof structures, especially of the lightweight structures. Significant differences are shown among the ČSN 730035 – 86, revise ČSN 730035 and ČSN EN 1991 in climatic loading (snow, wind). If any interventions into lightweight roof structures are planned it is necessary to pay attention to reliability of a load bearing structure. This paper describes some possibilities how to solve this problem.
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Steel-Concrete Columns Composed of High-Strength Materials
Röder, Václav ; Štěpánek, Petr (referee) ; Studnička,, Jiří (referee) ; Vičan,, Josef (referee) ; Karmazínová, Marcela (advisor)
The main objective of this thesis is the verification of the buckling strength of the composite compression members which were made from high-strength materials. This thesis is divided into four main chapters which are interconnected. The first chapter summarizes the current state of the problem of the compression members. The basis of this part is the elementary theories and researches, the task of this text is attempted to understand and obtain normative procedures which are important for practical use. The second part deals with the theoretical analysis of composite column, mainly with the examination of the individual effects on the buckling strength. The result of the first and the second parts is analytical algebraic equations which determine the buckling strength of the member. The third part contains the numerical analysis, which leads to create a numerical model of the compression column. The numerical model is used for the verification of the theoretical analysis and for the investigation of the behaviour of the column loaded by axial force. The last part deals with the experimental verification of the previous analyses. There are tested various types of the composite columns, which were made of steel with a yield strength up to 455 MPa and of the concrete with a cube compression strength up to 102 MPa. Experimental results confirmed the high reliability of centrally loaded column and every tested columns failed by flexural buckling. The final step is evaluation and comparison of the results obtained from previous four parts. It was founded that design criteria for centrally loaded steel-concrete column are too conservative and design relationships doesn´t use the positive properties of high-strength materials for economic design.
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Approximations in Stochastic Optimization and Their Applications
Mrázková, Eva ; Horová, Ivana (referee) ; Štěpánek, Petr (referee) ; Karpíšek, Zdeněk (advisor)
Mnoho inženýrských úloh vede na optimalizační modely s~omezeními ve tvaru obyčejných (ODR) nebo parciálních (PDR) diferenciálních rovnic, přičemž jsou v praxi často některé parametry neurčité. V práci jsou uvažovány tři inženýrské problémy týkající se optimalizace vibrací a optimálního návrhu rozměrů nosníku. Neurčitost je v nich zahrnuta ve formě náhodného zatížení nebo náhodného Youngova modulu. Je zde ukázáno, že dvoustupňové stochastické programování nabízí slibný přístup k řešení úloh daného typu. Odpovídající matematické modely, zahrnující ODR nebo PDR omezení, neurčité parametry a více kritérií, vedou na (vícekriteriální) stochastické nelineární optimalizační modely. Dále je dokázáno, pro jaký typ úloh je nutné použít stochastické programování (EO reformulace), a kdy naopak stačí řešit jednodušší deterministickou úlohu (EV reformulace), což má v praxi význam z hlediska výpočetní náročnosti. Jsou navržena výpočetní schémata zahrnující diskretizační metody pro náhodné proměnné a ODR nebo PDR omezení. Matematické modely odvozené pomocí těchto aproximací jsou implementovány a řešeny v softwaru GAMS. Kvalita řešení je určena na základě intervalových odhadů "optimality gapu" spočtených pomocí metody Monte Carlo. Parametrická analýza vícekriteriálního modelu vede na výpočet "efficient frontier". Jsou studovány možnosti aproximace modelu zahrnujícího pravděpodobnostní členy související se spolehlivostí pomocí smíšeného celočíselného nelineárního programování a reformulace pomocí penalizační funkce. Dále je vzhledem k budoucím možnostem paralelních výpočtů rozsáhlých inženýrských úloh implementován a testován PHA algoritmus. Výsledky ukazují, že lze tento algoritmus použít, i když nejsou splněny matematické podmínky zaručující konvergenci. Na závěr je pro deterministickou verzi jedné z úloh porovnána metoda konečných diferencí s metodou konečných prvků za použití softwarů GAMS a ANSYS se zcela srovnatelnými výsledky.
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Advanced Layered Composites for Dental Applications
Šedivý, Zbyněk ; Kučera, Jaroslav (referee) ; Štěpánek, Petr (referee) ; Jančář, Josef (advisor)
Disertační práce se zabývá mechanickou odezvou vrstevnatých kompozitů pro stomatologické aplikace. Různé skladby vrstev a různé částicové a vláknové kompozity jsou studovány v tříbodovém ohybu za pokojové teploty. Tyto výsledky jsou korelovány s výstupy dynamické termomechanické analýzy (DMTA) a optické analýzy (vysokorychlostní video záznam, SEM). Exeprimentální data byla použita pro srovnání s výsledky analytických a numerických modelů s cílem určit nejvhodnější model pro predikci základních mechanických vlastností vrstevnatých kompozitů. Na základě těchto analýz jsou navržena základní pravidla pro klinické použití vrstevnatých kompozitů ve stomatologických aplikacích jako jsou minimálně invazivní můstky nebo stabilizační dlahy.
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Separation of solid particles from biomass burning
Štěpánek, Petr ; Baláš, Marek (referee) ; Pospíšil, Jiří (advisor)
This thesis deals with aspects of the dust particles which occur in gaseous products from biomass combustion. The thesis introduces technologies by which solid particles capture from a combustion flow can be implemented. Principles and technical means of dust particles separation in mechanical separators are put in focus primarily. The thesis is concluded with a technical design of a cyclone separator.
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