<p>In this thesis, design aspects of fully integrated multibandmultistandard front-end receivers are investigated based onthree fundamental aspects: noise, linearity and operatingfrequency. System level studies were carried out to investigatethe effects of different modulation techniques, duplexing andmultiple access methods on the noise, linearity and selectivityperformance of the circuit. Based on these studies and thelow-cost consideration, zero-IF, low-IF and wideband-IFreceiver architectures are promising architectures. These havea common circuit topology in a direct connection between theLNA and the mixer, which has been explored in this work toimprove the overall RF-to-IF linearity. One front-end circuitapproach is used to achieve a low-cost solution, leading to anew multiband multistandard front-end receiver architecture.This architecture needs a circuit whose performance isadaptable due to different requirements specified in differentstandards, works across several RF-bands and uses a minimumamount ofexternal components.</p><p>Five new circuit topologies suitable for a front-endreceiver consisting of an LNA and mixer (low-noise converter orLNC) were developed. A dual-loop wide-band feedback techniquewas applied in all circuits investigated in this thesis. Threeof the circuits were implemented in 0.18 mm RF-CMOS and 25 GHzbipolar technologies. Measurement results of the circuitsconfirmed the correctness of the design approach.</p><p>The circuits were measured in several RF-bands, i.e. in the900 MHz, 1.8 GHz and 2.4 GHz bands, with S11 ranging from–9.2 dB to–17 dB. The circuits have a typicalperformance of 18-20 dB RF-to-IF gain, 3.5-4 dB DSB NF and upto +4.5 dBm IIP3. In addition, the circuit performance can beadjusted by varying the circuit’s first-stage biascurrent. The circuits may work at frequencies higher than 3GHz, as only 1.5 dB of attenuation is found at 3 GHz and nopeaking is noticed. In the CMOS circuit, the extrapolated gainat 5 GHz is about 15 dB which is consistent with the simulationresult. The die-area of each of the circuits is less than 1mm2.</p>

<p>Radar warning systems are life saving equipment in modern fighter aircraft. It is therefore vital that the system can tell the difference between a threat genuine frequency) and a false signal (spurious frequency). </p><p>This thesis presents a model aimed at predicting the frequencies and other parameters in the RF converter of the radar warning system. The components of the RF converter have been studied, measured, and modelled. The modelling tool has been the Simulink toolbox for Matlab. </p><p>Extreme accuracy has been sacrificed in order to make the model easy to use for the working engineer. Instead, this model presents a rough estimate of some of the most important properties of the radar warning system with just a few data sheet figures as input.</p><p>The simulation results are satisfactory as a whole. Simulink is the limiting factor in the implementation of the model. Significantly improved results can probably be obtained by working in another software environment.</p>

<p>This final year project describes the linearisation method Cartesian feedback and the design of such a feedback with a 2.4GHz power amplifier. </p><p>To investigate the functionality of the Cartesian feedback ideal blocks with no current consumption were made and then gradually analog circuits were introduced into the feedback. The Cartesian feedback design consists of a subtracter, a modulator and a preamplifier in the top path and a demodulator and a filter in the feedback path. The blocks that are discussed in this report are the subtracter and the modulator unit. The circuits are designed in a 0.35µm SiGe BiCMOS technology. </p><p>The result of the Cartesian feedback showed an increase in 1dB compression point by 6.2dBm and the IMD was improved by 17dB.</p>

Nonadhesive hydrate slurries have been shown to exhibit low viscosities in a field-scale flow loop when formed under appropriate conditions. The factors that favor formation of low-viscosity hydrate slurries include high Reynolds Number and Capillary Number, and high mass transfer and heat transfer rates. High liquid loading and high superficial fluid velocities are found to be conducive to the formation of low viscosity hydrate slurries. Dispersed bubble flow has been observed to facilitate flowable hydrate slurry production. Alternatively, the formation of nonadhesive hydrates at moderate superficial velocity is possible when a static mixer is used upstream of the hydrate formation location. For certain fields, low-viscosity hydrate slurry technology could eliminate the need for insulation and hydrate inhibitor chemicals (revised version of ICGH 2008 paper 5818) .

This paper covers the analysis of the main asphalt concrete production technological processes. It includes calculation of dosed materials for the two asphalt concrete mixes, as well as precision and stability of maintenance of temperature, necessary for the technological process. The above calculation is made following the production data printed by the mixer's printer. These data were divided into four groups: shift, week, month, season. This paper includes statistical indexes that reflects technological process of the asphalt concrete mixer: the arithmetical averages of real doses, temperatures and mixing time , the average square deviations Sq, variation's coefficients V etc. The methods, described in this paper, can be used for improvement of the normative documents and the quality control of produced asphalt concrete mixture. The paper consists of 143 pages and 129 drawings (some of them are in the addition) . The list of literature includes 29 bibliographic editions.

This research paper covers the analysis of the main asphalt concrete production technological processes. It includes calculation of dosed materials for the asphalt concrete mix, as well as precision and stability of maintenance of temperature necessary for the technological process.

Sraigtiniais transporteriais horizontalia, vertikalia ir nuožulnia kryptimi transportuojami įvairių tipų kroviniai ir medžiagos. Sraigtiniai transporteriai gali būti pritaikyti tiek pramonėje ar komercijos įmonėse, tiek buityje: popieriaus fabrikuose, skerdyklose, maisto perdirbimo įmonėse, fabrikuose, atliekų surinkimo centruose ar atskirtų kietųjų medžiagų pernešimui ir kt. / Screw conveyors in a horizontal, vertical and inclined towards the different types of transported goods and materials. Screw conveyors can be adapted for both industrial and commercial enterprises, both at home: paper mills, abattoirs, food processing plants, factories, waste collection centers or separated solids transfer and others.

Nanoparticles have received special attention over past few years as potential drug carriers for proteins/peptides and genes. Biodegradable polymeric poly (lactic-co-glycolic acid) (PLGA) nanoparticles are being employed as non-viral gene delivery systems for DNA. This work demonstrates a scalable technology for synthesis of nanoparticles capable of gene delivery. Cationic PLGA nanoparticles are produced by emulsiondiffusion- evaporation technique employing polyvinyl alcohol (PVA) as stabilizer and chitosan chloride for surface modification. A sonicator is used for the emulsion step and a static mixer is used for dilution in the diffusion step of the synthesis. A static mixer is considered ideal for the synthesis of PLGA nanoparticles as it is easily scalable to industrial production. The resulting nanoparticles are spherical in shape with size in the range of 100–250 nm and posses a zeta potential above +30 mV, indicating good stability of the colloid with a positive charge to bind to anionic DNA. The mechanism of nanoparticle formation was analyzed using multimodal size distributions (MSD), zeta potential data, and transmission electron microscopy (TEM) images. Several emulsion techniques and dilution effect were analyzed in this work. PVA acts as a compatibilizer for chitosan chloride and dilution of primary emulsion has little effect over the particle size of the PLGA nanoparticles.

Resumo: O conhecimento das propriedades reológicas é de grande importância no processamento, manuseio, controle de qualidade e desenvolvimento de diversos produtos. Determinar as propriedades de fluxo de produtos alimentícios é necessário para avaliar os efeitos dos diferentes métodos de processos ou de fatores como a potência requerida durante uma mistura, fornecendo subsídios à projetos de engenharia para o dimensionamento adequado de motores e bombas, que efetuem operação de mistura ou agitação com o mínimo de consumo de energia elétrica e a perda de carga em tubos de escoamentos. A concepção de um misturador ou sistema de agitação para fluidos passa necessariamente por uma análise reológica. Sendo os parâmetros empíricos como o índice de escoamento, o índice de consistência e a curva reológica dos alimentos, informações importantes no processamento e armazenamento de produtos alimentícios, este trabalho teve por objetivos: avaliar o uso de um misturador ou sistema de agitação Ika LR-2.ST com um agitador modelo Eurostar Power control-visc P7 acoplado a um impelidor do tipo âncora plana modificada e pela unidade de medida Ika Viscovlick VK 600 - na determinação das propriedades reológicas do mel de abelhas, suco concentrado de pessego, suco concentrado de laranja (sem adicao de acucar) e suco concentrado de goiaba; verificar o modelo matematico mais adequado ao comportamento de fluxo dos produtos analisados; calcular a potencia requerida numa operacao de agitacao ou mistura. O equipamento utilizado para a obtencao dos resultados foi o Sistema de Agitacao, devido a sua versatilidade em relacao ao Viscosimetro Convencional, pois este permite a analise com amostras com um volume de ate 2 litros, com fluidos em processos de reacoes quimicas, a baixa pressao, entre outras caracteristicas. Os parametros reologicos obtidos atraves do viscosimetro de cilindros concentricos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The knowledge of the rheological properties is of great importance in the processing, handling, quality control and development of several products. The determination of the properties of flow of nutritious products is necessary to evaluate the effects of the different methods of processes or of factors as the potency requested during a mixture, supplying subsidies to engineering projects for the appropriate dimensioning of motors and bombs, that make mixture operation or agitation with the electric minimum of energy consumption and the load loss in tubes of drainages. A mixer's conception or agitation system for fluids necessarily goes by an rheological analysis. Being the empiric parameters as the drainage index, the consistence index and the rheological curve of the foods, important information in the processing and storage of nutritive products, this work has had for objectives: the validation of a mixer's use or agitation system - Ika LR-2.ST with an agitator Eurostar Power control-visc coupled P7 to an impelidor of plain anchor modified type and for the unit of measure Ika Viscovlick VK 600 - in the determination of the rheological properties of the honey of bees, concentrated juice of peach, concentrated juice of orange (without addition of sugar) and concentrated juice of guava; the verification of the more appropriate mathematical model to the behavior of flow of the analyzed products; the calculation of the requested potency in an agitation operation or mixes. The System of Agitation was used because he is much more versatile than a conventional viscometer because it allows the work with a sample volume of up to two liters, with fluids in processes of chemical reactions, the low pressure, among other characteristics The rheological parameters obtained through the viscometer of concentric cylinders Brookfield with sensor LV - SC4-31, were used as pattern in the comparison with the data... (Complete abstract click electronic access) / Orientador: José Angelo Cagnon / Coorientador: Neusa Maria Pavão Battaglini / Banca: João Eduardo Guarnetti dos Santos / Banca: Jair Rosas da Silva / Mestre

abstract: ABSTRACT Ongoing research into wireless transceivers in the 60 GHz band is required to address the demand for high data rate communications systems at a frequency where signal propagation is challenging even over short ranges. This thesis proposes a mixer architecture in Complementary Metal Oxide Semiconductor (CMOS) technology that uses a voltage controlled oscillator (VCO) operating at a fractional multiple of the desired output signal. The proposed topology is different from conventional subharmonic mixing in that the oscillator phase generation circuitry usually required for such a circuit is unnecessary. Analysis and simulations are performed on the proposed mixer circuit in an IBM 90 nm RF process on a 1.2 V supply. A typical RF transmitter system is considered in determining the block requirements needed for the mixer to meet the IEEE 802.11ad 60 GHz Draft Physical Layer Specification. The proposed circuit has a conversion loss of 21 dB at 60 GHz with a 5 dBm LO power at 20 GHz. Input-referred third-order intercept point (IIP3) is 2.93 dBm. The gain and linearity of the proposed mixer are sufficient for Orthogonal Frequency Division Multiplexing (OFDM) modulation at 60 GHz with a transmitted data rate of over 4 Gbps. / Dissertation/Thesis / M.S. Electrical Engineering 2010