The basic cube satellite (CubeSat) is a modern small satellite that has a standard size of about one liter (the 1U CubeSat). Three 1U CubeSats could be stacked to form a 3U CubeSat. Their low-cost, short development time, and ease of deployment make CubeSats popular for space research, geographical information gathering, and communication applications. An antenna is a key part of the CubeSat communication subsystem. Traditionally, antennas used on CubeSats are wrapped-up wire dipole antennas, which are deployed after satellite launch. Another antenna type used on CubeSats is the patch antenna. In addition to their low gain and efficiency, deployable dipole antennas may also fail to deploy on satellite launch. On the other hand, a solid patch antenna will compete for space with solar cells when placed on a CubeSat face, interfering with satellite power generation. Slot antennas are promising alternatives to dipole and patch antennas on CubeSats. When excited, a thin slot aperture etched on a conductive sheet (ground plane) is an efficient bidirectional radiator. This open slot antenna can be backed by a reflector or cavity for unidirectional radiation, and solar cells can be placed in spaces on the ground plane not occupied by the slot. The large surface areas of 3U CubeSats can be exploited for a multifunctional antenna by integrating multiple thin slot radiators, which are backed by a thin cavity on the CubeSat surfaces. Solar cells can then be integrated on the antenna surface. Polarization diversity and frequency diversity improve the overall performance of a communication system. Having a single radiating structure that could provide these diversities is desired. It has been demonstrated that when a probe excites a square cavity with two unequal length crossed-slots, the differential radiation from the two slots combines in the far-field to yield circular polarization. In addition, it has been shown that two equal-length proximal slots, when both fed with a stripline, resonate at a frequency due to their original lengths, and also resonate at a lower frequency due to mutual coupling between the slots, leading to a dual-band operation. The multifunctional antenna designs presented are harmonizations and extensions of these two independent works. In the multifunctional antenna designs presented, multiple slots were etched on a 83 mm x 340 mm two-layer shallow cavity. The slots were laid out on the cavity such when the cavity was excited by a probe at a particular point, the differential radiation from the slots would combine in the far-field to yield Left-Handed Circular Polarization (LHCP). Furthermore, when the cavity was excited by another probe at an opposite point, the slots would produce Right-Handed Circular Polarization (RHCP). In addition, as forethought, these slots were laid out on the cavity such that some slots were close together enough to give Linearly Polarized (LP) dual-band operation when fed with a stripline. This antenna was designed and optimized via computer simulations, fabricated using Printed Circuit Board (PCB) technology, and characterized using a Vector Network Analyzer (VNA) and NSI Far Field Systems.

The aim of diploma thesis is to design and create a project documentation of a multifunctional building. The building is situated in Banská Bystrica in a slightly sloping terrain. The building is divided into 3 parts - A, B, C, that are connected by 2 floors of underground garages and the first floor, where are situated commercial premises. There are apartments located on the next 5 floors, 18 of them in each part, with a layout of 2+kk and 3+kk. The load-bearing system of this building consists of a reinforced concrete skeleton, supplemented by reinforced concrete and masonry perimeter walls. The roof is flat and rugged, partly walkable and partly covered with gravel and vegetation. The overall character of the building fits into the surrounding buildings.

This diploma work is dealing with the design of a multifunctional complex. These are two buildings on plot number 8618 on cat. the territory of the city of Trnava. The technical background of the buildings and hygiene background for employees are designed in the buildings. Vertical support structures are from ceramic blocks. Horizontal support structures are designed as reinforced concrete monolithic. The construction is based on the foundation strips. The roofing of the buildings is performed by a single-coated area non-permitable roof

Urban study solves the problem of the river in the city. The river and its waterfront is used for daily recreation of the population while allowing the passage of floods without significant damage. The area is designed as a multi-functional.

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The thesis aims to illustrate and highlight the potential of graphene-based fillers in reinforcing organic coatings deposited by cataphoresis. Thanks to particular surface modification processes of the graphene flakes, these have been properly distributed within the polymer matrix, providing the composite coating with remarkable protective performance. The optimization of the deposition process parameters, as well as the amount of filler, also allowed to improve the mechanical and conductivity properties of the cataphoretic matrix, suggesting the possibility of realizing multifunctional coatings. Finally, these ’smart’ coatings were made by combining two deposition techniques, creating two layers with distinct purposes, containing different types of graphene-based fillers. The cataphoretic primer provided the substrate with high corrosion protection, while the spray top coat possessed high properties of electrical conductivity and resistance to abrasion phenomena. Ultimately, graphene has proven to be an excellent resource as a reinforcing filler in multifunctional organic coatings.

The aim of my Ph.D. thesis is to summarize my research on the development of multimateiral multifunctional fibers for bio-related application, mainly in the fields of neural interfacing and bioimpedance sensing. Understanding the cytoarchitecture and wiring of the brain requires improved methods to record and stimulate large groups of neurons with cellular specificity. This requires the development of improved miniaturized neural interfaces that integrate into brain tissue without altering its properties. Despite the advancement of the existing neural interface technologies such as microwires, silicon-based multielectrode arrays, and electrode arrays with flexible substrates, the physical properties of these devices limit their access to one, small brain region with single implantation. Beyond neural interfacing, extracting molecular information is crucial for understanding many neurological diseases and disorders. The most adapted methods are fast scan cyclic voltammetry and microdialysis. However, both have some limitations such as offline sensing or lack of selectivity. Furthermore, by concentrating optical fields at the nanoscale, plasmonic nanostructures can serve as optical nanoantennas to achieve ultrasensitive bio-/chemical sensing. But due to the limitation of the sensing mechanism, it is hard to perform the plasmonic sensing in live animals. Moreover, the relatively poor electrical performance of the electrode materials that can be utilized in the thermal drawing process limits the function of the fiber in other types of biomedical application, such as deep brain stimulation and electrochemical sensing. For example, the large inherent electrical resistance of the electrode material will significantly interference the electrical impedance result while the main purpose of this kind of study is to explore the frequency-dependent electrical properties of the tested subjects. To overcome above difficulties This thesis introduces broad application of multimaterial multiplexed fibers in biomedical areas. I first describe the development and application of spatially expandable multifunctional fiber-based probes for mapping and modulating brain activities across distant regions in the deep brain (Chapter 2). Secondly, I present the flexible nano-optoelectrodes integrated multifunctional fiber probes that can have hybrid optical-electrical sensing multimodalities, including optical refractive-index sensing, surface-enhanced Raman spectroscopy, and electrophysiological recording (Chapter 3). Thirdly, I demonstrate that hollow multifunctional fibers enable in-line impedimetric sensing of bioink composition and exhibit selectivity for real-time classification of cell type, viability, and state of differentiation during bioprinting (Chapter 4). The same device allows for local delivery of immune checkpoint blockade antibodies and for monitoring of clinical outcomes by tumor impedance measurement over the course of weeks with the photodynamic therapy option to enhance anti-tumor immunity and prolong intratumoral drug retention (Chapter 5). An overview future work has been summarized (Chapter 6). / Doctor of Philosophy / Electrode technology has played an indispensable role in neuroscience community since the first employment of insulated tungsten wire in cat brain in 1950s. The electrophysiological signal acquired from or the electrical current delivered to the brain tissue using the implanted electrode, has permitted us to understand the functional networks in the brain and treat neurological diseases. Over the past decades, significant progress has been made in developing miniaturized electrical neural interfaces. The development of optogenetics involving genetically-modified neurons that express light-sensitive proteins (opsins) has provided a powerful tool for modulating the neuronal activity to be switched on or off using light at a particular wavelength. Leveraging the thermal drawing process (TDP) from optical fiber industry for producing conventional silica fibers, multifunctional fiber-based neural probes have recently been developed, allowing for simultaneous optical stimulation, electrical recording, and drug delivery in vivo. However, the interfacing sites in these fiber-based neural probes have been restricted to a single location (at the fiber tip) so far, making the broad application of these probes unfeasible. Beyond neural interfacing, extracting molecular information is crucial for understanding many neurological diseases and disorders. The most adapted methods are fast scan cyclic voltammetry and microdialysis. However, both have some limitations such as offline sensing or lack of selectivity. Furthermore, by concentrating optical fields at the nanoscale, plasmonic nanostructures can serve as optical nanoantennas to achieve ultrasensitive bio-/chemical sensing. But due to the limitation of the sensing mechanism, it is hard to perform the plasmonic sensing in live animals. To overcome these limitations, we first developed a platform that provides three-dimensional coverage of brain tissue through multifunctional polymer fiber-based neural probes capable of interfacing simultaneously with neurons in multiple sites (Chapter 2). In a later study, we demonstrate that conductive nanoantenna arrays can be integrated with microelectrodes on the tip of multifunctional fiber probes as nano-optoelectrodes to enable optical bio-/chemical spectroscopy as well as to improve electrophysiology recording (Chapter 3). Besides, inspired by a convergence fiber drawing method, we have also managed to incorporate copper wires inside multifunctional fibers with a hollow channel in the center, in favor of high electrical conductivity. This technology developed here holds great promise for electrochemical impedance sensing of the tested media without the interference from the utilized electrodes' high resistance. Hence, by exploiting the functional fibers and the superior electrical performance, the copper-electrode-based fiber has been used for in vitro bioink bioimpedance sensing during 3D printing process (Chapter 4) and in vivo tumor impedance monitoring and drug delivery (Chapter 5). In summary, my research produces unique platforms for fundamental research studies as well as the readily translational application for human subjects. Given the scalable, straightforward, and versatile fabrication method, the multifunctional fibers delivered by our team would pave the way for new engineered tools for broad biomedical community.

Thesis (PhD(Agric) (Agriculture))--University of Stellenbosch, 2009. / Traditionally, agricultural land was regarded mainly as a production factor. Accordingly, in their application of the market sales comparison approach to agricultural land, valuers relied on a set of attributes related to agricultural production as the primary determinants of an agricultural property’s highest and best use (HBU) and market value. These characteristics were measurable and related to the property’s income-generating capacity. The emergence of a multi-functional rural land market with alternative uses of agricultural land, such as for lifestyle purposes, has transformed this concept. Lifestyle inspired buyers often focus on a wider range of attributes not necessarily related to income, but associated more with satisfaction derived from the property. This creates a measurement problem for agricultural land valuers, as the characteristics valued by lifestyle buyers are more intangible and subjective, which leave valuers without a base from which to value such properties. The presence of lifestyle inspired buyers makes agricultural land valuations more demanding as it implies different interpretations of the same farm and complicates the choice of a single HBU. The continued use of familiar conventional farming attributes by valuers when valuing farms where lifestyle motivations are present, and the omission of less measurable characteristics, implies that the market sales comparison method cannot be executed accurately. The objectives of the study were twofold: to reveal the dominance of value attributes applicable to farming as HBU when valuing farms bought primarily for lifestyle purposes and to identify the characteristics of land important to lifestyle inspired farm buyers.

The present work is divided into two sections. The first section deals with the synthesis of regenerable adsorbents for the removal of arsenic from contaminated waters. An adsorbent based on carboxymethylated polyethylenimine grafted agarose gels was synthesized and characterized as a regenerable synthetic ferric oxide adsorbent with high capacity for arsenate ions at pH 3.0. Similarly, four metal ion chelating adsorbents based on dipicolylamine were synthesized and characterized with respect to their Cu(II), Fe(III) and As(V) adsorption capacities. The most efficient adsorbents were Nov-PEI-DPA and Nov-TREN-DPA. Additionally, a commercial ion exchange resin was modified with permanganate to oxidize arsenite into arsenate. A complete oxidation-adsorption system was proposed in which a column packed with the oxidation resin was connected in series with an adsorbent column composed of the polyethylenimine grafted agarose gels.The second section involved work with magnetic nanoparticles. First, composite adsorbents consisting of magnetic particles encapsulated within agarose beads with and without grafted iminodiacetic acid (IDA) chelating groups were synthesized. The adsorption capacity of the adsorbents for Cu(II), Fe(III) and As(V) at different concentrations was investigated. Batch experiments were carried out to determine the Fe(III) and As(V) adsorption isotherms for the magnetic Novarose-IDA. Regenerability of the adsorbent was achieved with a pH change of the inlet solution, without affecting its magnetic or adsorption properties.Magnetic composite particles were synthesized for biomedical applications. First, magnetic nanoparticles were coated with silica and then used for gold nanoshell production. These nanoshells were functionalized with a Brij S10 derivative, containing carboxylic groups, using dodecanethiol as a bridging agent to incorporate a fluorescent biomolecule.Finally, magnetic and gold particles were encapsulated in PLGA nanoparticles. Docetaxel was loaded on these multifunctional nanoparticles and released studies were performed at 37°C. The presence of magnetite, colloidal gold and gold nanoshells in the PLGA nanoparticles was revealed by the coloration acquired by the polymeric nanoparticles. The release of drug from the polymeric nanoparticles showed a biphasic behavior with an initial burst followed by a prolonged slow release. There was no effect of the presence of magnetic or metallic particles on docetaxel release.