100 research outputs found
Childern´s Sanatorium Ostrov u Macochy
Architektonická studie se zabývá návrhem Dětské léčebny se speleoterapií v Ostrově u Macochy. Návrh pracuje s myšlenkou propojení s okolní přírodou, reaguje na svažitý terén a snaží se naplnit obsáhlý stavební program. Charakteristickým prvek je využití přírodního materiálu – dřeva v rámci obvodového pláště, který definuje architektonický výraz objektu. Je kladen důraz na obnovitelné zdroje energie.The architectural study deals with the design of Childern´s sanatorium with speleotherapy in Ostrov u Macochy. Design works with the idea of connecting with the surrounding nature, responds to the slopping terrain and tries to fulfill a comprehensive construction program. A characteristic element is the use of natural material – wood within the curtaing walling, which defines the architectural expression of the building. Emphasis is placed on renewable energy sources.
Multifunctional building Brno - Líšeň
Předmětem bakalářské práce je vypracování projektové dokumentace polyfunkčního domu v Brně – Líšni. Objekt má 2 nadzemní podlaží a 2 podzemní podlaží. V prvním nadzemním podlaží se nachází pronajímatelné prostory (obchody). Ve druhém nadzemním a prvním podzemním podlaží se nachází pronajímatelné prostory (doktoři, administrativa). Ve druhém podzemním podlaží se nachází podzemní garáže. Vjezd do garáže je zajištěn venkovní rampou. Nosným systémem je železobetonový skelet. Objekt je založen na železobetonových patkách a pasech. Vnitřní schodiště je monolitické železobetonové. Střechy jsou navrženy jako ploché jednoplášťové.Subject of this bachelor´s thesis is to develop project documents of multifunctional building in Brno – Líšeň. The building has 2 floors and 2 underground floors. On the first floor there are leasable spaces (shops). On the second floor there are leasable spaces (office, doctors). On the first underground floor there are also leasable spaces (office, doctors). On the second underground floor there is car parking. The netrance do the parking floor is secured by outdoor ramp. Structural systém of building is cast-in-place rainforced concrete. The building is based on simple fundation pads and strip foundations. An internal staircase is cast-in-place reinforced concrete. The roofs of the building are designed as warm flat roofs.
Optical sorting and detection of sub-micron objects in a motional standing wave
An extended interference pattern close to surface may result in both a
transmissive or evanescent surface fields for large area manipulation of
trapped particles. The affinity of differing particle sizes to a moving
standing wave light pattern allows us to hold and deliver them in a
bi-directional manner and importantly demonstrate experimentally particle
sorting in the sub-micron region. This is performed without the need of fluid
flow (static sorting). Theoretical calculations experimentally confirm that
certain sizes of colloidal particles thermally hop more easily between
neighboring traps. A new generic method is also presented for particle position
detection in an extended periodic light pattern and applied to characterization
of optical traps and particle behaviorComment: 5 pages, 6 figures, Optical Trapping pape
INFLUENCE OF SUBSTRATE THICKNESS ON DIFFUSE COPLANAR SURFACE BARRIER DISCHARGE PROPERTIES
In presented work the influence of dielectric barrier thickness on the parameters of Diffuse Coplanar Surface Barrier Discharge was investigated. The discharge was operated at atmospheric pressure laboratory air. The electrical parameters of the system were studied both experimentally and using numerical simulations. The discharge pattern was studied as well using intensified CCD camera
Synchronization of spin-driven limit cycle oscillators optically levitated in vacuum
We explore, experimentally and theoretically, the emergence of coherent
coupled oscillations and synchronization between a pair of non-Hermitian,
stochastic, opto-mechanical oscillators, levitated in vacuum. Each oscillator
consists of a polystyrene microsphere trapped in a circularly polarized,
counter-propagating Gaussian laser beam. Non-conservative, azimuthal forces,
deriving from inhomogeneous optical spin, push the micro-particles out of
thermodynamic equilibrium. For modest optical powers each particle shows a
tendency towards orbital circulation. Initially, their stochastic motion is
weakly correlated. As the power is increased, the tendency towards orbital
circulation strengthens and the motion of the particles becomes highly
correlated. Eventually, centripetal forces overcome optical gradient forces and
the oscillators undergo a collective Hopf bifurcation. For laser powers
exceeding this threshold, a pair of limit cycles appear, which synchronize due
to weak optical and hydrodynamic interactions. In principle, arrays of such
Non-Hermitian elements can be arranged, paving the way for opto-mechanical
topological materials or, possibly, classical time crystals. In addition, the
preparation of synchronized states in levitated optomechanics could lead to new
and robust sensors or alternative routes to the entanglement of macroscopic
objects
Thermal tuning of spectral emission from optically trapped liquid-crystal droplet resonators
Surfactant-stabilized emulsion droplets of liquid crystals (LCs) suspended in water and labeled with a fluorescent dye form active, anisotropic optofluidic microresonators. These microresonators can host whispering gallery modes (WGMs), high-quality morphology-dependent optical resonances that are supported due to the contrast of refractive index between the LC droplets and the surrounding aqueous medium. In addition, owing to the refractive index contrast, such LC emulsion droplets can be stably trapped in three dimensions using optical tweezers, enabling long-term investigation of their spectral characteristics. We explore various combinations of fluorescently dyed LC droplets and host liquid-surfactant systems and show that the WGM emission spectra of optical resonators based on optically trapped LC emulsion droplets can be largely and (almost) reversibly tuned by controlled changes of the ambient temperature. Depending on the actual range of temperature modulation and LC phase of the studied droplet, thermally induced effects can either lead to phase transitions in the LC droplets or cause modifications of their refractive index profile without changing their LC phase. Our results indicate feasibility of this approach for creating miniature thermally tunable sources of coherent light that can be manipulated and stabilized by optical forces
Observations of a PT-like phase transition and limit cycle oscillations in non-reciprocally coupled optomechanical oscillators levitated in vacuum
We explore the collective non-Hermitian dynamics of a pair of
non-conservatively coupled optomechanical oscillators. The oscillators consist
of silica nanoparticles optically levitated in vacuum in two parallel pairs of
interfering counter-propagating laser beams. By adjusting the relative phase,
polarization, and separation of the trapping laser beams, we set the optical
interaction between the particles to be purely non-reciprocal. Continuously
varying the relative power of the trapping beams over a predefined range takes
the system through transition, analogous to a parity-time (PT) phase
transition. Decreasing the dissipation rate within the non-equilibrium phase
induces a Hopf bifurcation resulting in the formation of collective limit cycle
oscillations similar to those observed in phonon lasers. Such systems provide a
novel platform for exceptional point optomechanical sensing and due to their
wide flexibility and tunability of the interactions can be extended to
multi-particle systems, paving the way for the development of topological
optomechanical media
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Microfluidic Cultivation and Laser Tweezers Raman Spectroscopy of E. coli under Antibiotic Stress
Analyzing the cells in various body fluids can greatly deepen the understanding of the mechanisms governing the cellular physiology. Due to the variability of physiological and metabolic states, it is important to be able to perform such studies on individual cells. Therefore, we developed an optofluidic system in which we precisely manipulated and monitored individual cells of Escherichia coli. We tested optical micromanipulation in a microfluidic chamber chip by transferring individual bacteria into the chambers. We then subjected the cells in the chambers to antibiotic cefotaxime and we observed the changes by using time-lapse microscopy. Separately, we used laser tweezers Raman spectroscopy (LTRS) in a different micro-chamber chip to manipulate and analyze individual cefotaxime-treated E. coli cells. Additionally, we performed conventional Raman micro-spectroscopic measurements of E. coli cells in a micro-chamber. We found observable changes in the cellular morphology (cell elongation) and in Raman spectra, which were consistent with other recently published observations. The principal component analysis (PCA) of Raman data distinguished between the cefotaxime treated cells and control. We tested the capabilities of the optofluidic system and found it to be a reliable and versatile solution for this class of microbiological experiments
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