A 10-way power divider based on a transducer and a radial junction operating in the circular TM01 mode

This work presents a 10-way Ku-band power divider using a mode transducer and a radial junction connected by an overmoded circular waveguide operating in the TM 01 mode. The circular symmetry of this mode has been exploited to obtain a power divider with the rectangular output ports radially distributed along the broad wall of the waveguides in H-plane configuration. This topology provides the same amplitude and phase for all the output ports. At the same time, a compact profile has been obtained, introducing a simple manufacturing for the two components of the divider. The first component is a mode transducer converting the TE 10 mode in the rectangular waveguide to the TM 01 mode in the circular waveguide. It is based on a novel topology providing a very high purity in the mode conversion with an attenuation for the other propagating mode, the TE 11c , higher than 60 dB. The second component is a 10-way radial junction that must work under the excitation of the TM 01 , whose special features, since this mode is not the fundamental one of the circular waveguide, will be highlighted. The final design has been validated with an experimental prototype, proposing a manufacturing based on four simple parts. This has been the key to obtain an experimental prototype with specifications in the state-of-the-art. The measured efficiency is better than 96.5% in a 16.7% relative frequency bandwidth from 11 GHz to 13 GHz, with return losses better than 25 dB in the common port. The measured difference between the signals at the output ports of the prototype is ±0.3 dB for the amplitudes and ±0.45° for the phases. A comparison of the obtained results with another divider based on the TE 01 mode shows the potential of the presented design for becoming an alternative to the more extended TE 01 -based power dividersThis work was supported by the Spanish Government through the Agencia Estatal de Investigacion, Fondo Europeo de Desarrollo Regional (AEI/FEDER, UE), under Grant TEC2016-76070-C3-1/2-R (ADDMATE

Development of a high-performance W-band duplexer for plasma diagnosis using a single band with dual circular polarization

Discrepancia entre la información que aparece en el artículo que indica que el copyright es de Elsevier, y la información que aparece en la página de la revista y en el Copyright Clearance Center que indican © 2019 The Authors. Published by Elsevier B.V., así como que el artículo está publicado en Open Access under a Creative Commons licenceThis work presents the design and experimental validation of a high performance, compact, waveguide duplexer operating from 91.5 to 96.5 GHz for its integration in diverse W-band microwave equipment as in plasma diagnosis applications. It uses a single frequency band, with two signals discriminated by different orthogonal circular polarization, which is generated by means of a septum orthomode transducer (OMT) polarizer. Moreover, this component is optimized loaded with the horn antenna for improving the overall system performance. It is explained how these two components are integrated into a very compact duplexer, designed using efficient numerical algorithms. The manufacturing process by mean of high precision milling, and including electrical discharge machining (EDM) has led to excellent performances. The measured return loss level and isolation are higher than 30 dB, and the insertion loss level is below 0.3 dB. Finally, the key parameter in this device, which reflects the symmetry in the manufacturing process, i.e., the axial ratio, is lower than 0.6 dB for both polarizations, an excellent result showing the potential of the presented designThis work was supported by the Spanish government under grants (ADDMATE) TEC2016-76070-C3-1/2-R (Agencia Estatal de Investigación, Spain, Fondo Europeo de Desarrollo Regional: AEI/FEDER/UE) and the program of Comunidad de Madrid, Spain S2013/ICE-3000 (SPADERADARCM

High-performance 16-way Ku-band radial power combiner based on the TE01-circular waveguide mode

This work presents a 16-way Ku-band radial power combiner for high power and high frequency applications, using the very low loss TE01 circular waveguide mode. The accomplished design shows an excellent performance: the experimental prototype has a return loss better than 30 dB, with a balance for the amplitudes of ( 0.15 dB) and ( 2.5 ) for the phases, in a 16.7% fractional bandwidth (2 GHz centered at 12 GHz). For obtaining these outstanding specifications, required, for instance, in highfrequency amplification or on plasma systems, a rigorous step-by-step procedure is presented. First, a high-purity mode transducer has been designed, from the TE10 mode in the rectangular waveguide to the TE01 mode in the circularwaveguide, with very high attenuation (>50 dB) for the other propagating and evanescent modes in the circularwaveguide. This transducer has been manufactured and measured in a back-to-back configuration, validating the design process. Second, an E-plane 16-way radial power divider has been designed, where the power is coupled from the 16 non-reduced-height radial standardwaveguides into the TE01 circularwaveguide mode, improving the insertion loss response and removing the usual tapered transformers of previous designs limiting the power handling. Finally, both the transducer and the divider have been assembled to make the final radial combiner. The prototype has been carefully manufactured, showing very good agreement between the measurements and the full-wave simulationsThe authors would like to thank INMEPRE S.A., the diligence in the manufacturing process. This work was supported by the Spanish government under Grant (ADDMATE) No. TEC2016-76070-C3-1/2-R (AEI/FEDER/UE) and the program of Comunidad de Madrid S2013/ICE-3000 (SPADERADARCM

Caracterização mecânica de toros de madeira lamelada colada

Neste trabalho descreve-se a caracterização mecânica de toros de madeira lamelada colada pertencentes a um sistema construtivo de casas pré-fabricadas de madeira. Os módulos de elasticidade global e local à flexão, à compressão paralela e perpendicular às fibras, bem como os valores das respectivas tensões resistentes, foram obtidos de acordo com a norma Europeia EN 408:2003. Na análise destas propriedades foi tida em conta a influência do número de lamelas, ao considerar-se para cada uma das propriedades mecânicas analisadas três valores para a espessura dos toros

Lajes mistas de madeira-betão

Em trabalhos de reabilitação de edifícios antigos é prática comum a substituição dos pavimentos de madeira por lajes de betão. Esta solução produz um aumento de massa que pode conduzir a uma significativa diminuição da segurança estrutural. Estudos recentes mostram que a utilização de pisos mistos de madeira-betão, reutilizando ou não as traves existentes, conduz a soluções mais leves e melhor enquadradas na arquitectura. O comportamento deste tipo de lajes é fortemente condicionado pela ligação madeira-betão. Neste trabalho, analisam-se as tipologias mais correntes, os sistemas de ligação disponíveis e a metodologia de cálculo preconizada pelo Eurocódigo 5 para o dimensionamento de lajes mistas de madeira-betão, apresentando-se a resolução de um exemplo numérico. São ainda descritas novas tipologias estruturais, em particular, aquelas orientadas para a pré-fabricação

Analysis of the quality of life after an endoscopic thoracic sympathectomy : a business intelligence approach

Primary hyperhidrosis, a disorder characterized by an excessive sweating, has been treated by endoscopic thoracic sympathectomy. As a consequence of the surgery, patients improved their overall quality of life. Their day-by-day activities are not affected, or are less affected, by this disorder, and their emotional state verifies a significant improvement, from a situation of shame and self-punishing to what we could say a normal life. This paper presents the analysis of the quality of life of 227 patients that were treated by an endoscopic thoracic sympathectomy. The study was based on the use of business intelligence technologies, which allowed the storage, the analysis and the reporting of all the relevant findings. In technological terms, this paper illustrates the database and data analysis developments needed in a specific healthcare application domain. For data storage, a data mart was designed addressing the relevant attributes. For data analysis, on-line analytical processing and data mining technologies were used to show the evolution of the patients’ health condition and the incidence of complications or side effects as consequence of the surgery.(undefined

Implementação de um sistema de Business Intelligence para a análise da qualidade de vida pré e pós-operatória

A hiperhidrose primária é provocada por uma disfunção do sistema nervoso simpático e é caracterizada por uma sudorese excessiva, a qual condiciona a qualidade de vida dos pacientes que possuem esta doença. A simpaticectomia é uma técnica cirúrgica que pode ser utilizada no tratamento da hiperhidrose primária. Este capítulo apresenta a análise da qualidade de vida de 227 pacientes que foram submetidos a uma simpaticectomia torácica endoscópica. As análises efectuadas recorreram a um sistema de Business Intelligence (BI), o qual permitiu o armazenamento, a manipulação e a análise dos dados recolhidos. Para o armazenamento dos dados foi concebido um Data Mart e para a sua análise foram utilizadas as tecnologias On-line Analytical Processing (OLAP) e Data Mining. A análise dos dados recolhidos permitiu verificar a evolução da qualidade de vida dos pacientes e, ainda, a incidência de complicações ou efeitos secundários como consequência da cirurgia

Diagnosis and analysis of two king-post trusses

An accurate geometric and mechanical evaluation of two king-post trusses, based in grading results with data gathered from NDT as well as from mechanical evaluation, followed by full-scale tests were performed. The trusses were reassembled in laboratory and submitted to a series of cyclic tests under symmetric and asymmetric loading. Strengthening techniques evaluated in precedents research steps were used in a second phase of the carrying tests.The first author gratefully acknowledges the Portuguese Foundation for Science and Technology, for his PhD grant SFRH/BD/18515/2004. The research described in this paper was conducted with financial support of the Portuguese Foundation for Science and Technology (POCI/ECM/56552/2004). This work has been carried out with a partial financial contribution of the Italian Earthquake Engineering Laboratory Network (RELUIS), within the research program carried out for the Italian Agency for Emergency Management

Structural analysis of two King-post timber trusses: non-destructive evaluation and load-carrying tests

The misunderstanding of the overall behaviour of traditional timber trusses can result in incorrect strengthening interventions or, frequently, on their replacement. Timber roof structures need a more concise knowledge of the real behaviour to determine internal loads and control the load transfer. For that, laboratory tests on scaled or full-scale specimens of members, connections and trusses are needed. In this paper, an accurate geometric and mechanical evaluation of the timber elements of two Kingpost timber trusses, based on grading results with data gathered from non-destructive tests (NDT), including mechanical evaluation of the modulus of elasticity in bending (MoE), followed by full-scale carrying tests were performed. The trusses were reassembled in laboratory and submitted to a series of symmetric and non-symmetric cyclic tests, according to the Limit States. Strengthening techniques evaluated in precedent research steps were used in a second phase of the load-carrying tests