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In order to apply to S-Band (1-4.5 GHz) of wireless communication system, we designed and fabricated a high-insolating RF-MEMS switch by surface micromachining technology in this study. In terms of the micro switch, we performed the structural design, high frequency simulation, components process integration and high-frequency measurement in this study. Especially for making components be high-isolation, low-loss and low-driving voltage, we proposed the following three methods: (i) adjusting the space and width of the transmission lines to improve the RF performance; (ii) applying the stress imbalance, by using dual metal composite top electrode, to form a arched contact electrode and reduce the drive voltage efficiently; (iii) using non-isometric spring structure to stabilize the electrode movement of the components. Besides, we did the optimizing simulation for this study, which were supported by Ansoft-HFSS and ADS, in terms of the micro switch which has different structural design as mentioned above. The size of the optimized RF micro-switch which we developed for this study is only 145 £gm ¡Ñ 205 £gm. Switched from on-state to off-state, the component needs 36.5V drive voltage only. According to the result of the commercial network analyzer in 1-4.5GHz frequency range, the isolation rate of the components reaches -59.721dB while off-state; the insert los reaches -1.625dB while on-state.

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The subject of the master thesis is the design and assessment of the supporting roof steel structure on the building, which will be used for various sports events in Znojmo. The building has a rectangular floor plan with dimensions of 50 x 60 m. The height at the top is 15 m. The trusses are articulated on concrete columns. Structure stability ensures system of bracings. The work contains a static calculation of the main load-bearing elements, including the relevant joints. The roof and cladding consist of sandwich panels.

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Arkinės perdangos dėl savo veiksmingumo yra dažnos šiuolaikiniuose pėsčiųjų tiltuose. Racionali apybrėžos forma (dažniausiai kvadratinė parabolė) lemia šių konstrukcijų racionalų įrąžų pasiskirstymą. Arkų eksploatacinio funkcionavimo pagrindinis bruožas yra tas, kad vertikaliosios apkrovos, be vertikalių reakcijų paduose, sukelia ir horizontalias reakcijas (skėtimo jėgas). Be tradicinių arkinių perdangų iš istorijos šaltinių yra žinoma ir unikalios sandaros arkinių lęšio formos tiltų. Jie reikšmingi ne tik dėl savo unikalios formos, bet ir dėl istorinės vertės, nes buvo statomi du paskutinius XIX a. dešimtmečius, kaip dinozaurai mėgavosi savo istorine epocha prieš daug, daug metų ir tada staiga išnyko. Darbe atliekama tradicinio arkinio tilto, bei arkinių plieninių lęšio formos tiltų elgsenos analizė, keičiant pagrindinius geometrinius arkų – juostų parametrus, arkų tinklelio formą ir tinkleliui taikant išankstinį įtempimą. Pirmame skyriuje aptariama arkinių ir arkinių kombinuotųjų tiltų konstrukcinės schemos, jų skaičiavimo metodai. Formuluojami darbo tikslas ir uždaviniai. Antrame skyriuje atliekama tradicinio arkinio tilto ir arkinių abipusiai iškilos formos tiltų elgsenos analizė, veikiant simetrinėms ir asimetrinėms apkrovoms. Trečiame skyriuje atliekama gautų rezultatų lyginamoji analizė, lyginant tiltų konstrukcijas pagal įrąžų pasiskirstymą jų elementuose ir pagal tiltų masės kriterijų. / Due to their effectiveness, arched entablatures are common in modern footbridges. Well-balanced form of contour (most commonly quadratic parable) determines a well-balanced stress distribution of these constructions. The main feature of the running behaviour of arcs is that vertical loads without vertical reactions in the hearths create horizontal reactions as well (forces of thrust). Not only traditional bridges with arched entablatures but also unique structured arched lenticular bridges. They are significant not only for its unique shape and few examples but also for the historic value that they were only built during the last two dacedes of 19th century, like dinasors had enjoyed a historic age long long ago and then suddenly vanished at all. In this work carries out the analysis of behaviour of traditional arched bridge and arched lenticular bridges made of stell by changing the main geometric parameters of arcs-strips, form of the system of arcs and applying pre-stress of the system. The first chapter discusses the schemes of construction of arched and arched combined bridges, methods of their calculation. The goal and tasks of the work are formulated. The analysis of the behaviour of traditional arched bridge and arched lenticular bridges (when it is affected by symmetric and asymmetric loads) is carried out in the second chapter. Comparative analysis of the results is performed in the third chapter by comparing constructions of the bridges according to stress... [to full text]

The aim of the work is to design steel structure exhibition pavilion. The building is situated in Brno. The construction is processed in two options. The option A is designed in variant of arched space frame. The internal ground plan dimensions of the building are 42 x 72 meters. Space frame is hinged to the structure of columns. Height in the top of the ship is 16,834 metres. The option B is designed in variant arched truss. The internal ground plan dimensions of the building are 42 x 70 meters. Arched truss is hinged to the structure of columns. Height in the top of the ship is 18,334 metres. The spatial rigidity of the structure is ensured by cross braces. Roof cladding and walls will be made using sandwich panels of KINGSPAN. The main material will be used steel S235.