Polo-Lopez, Lucas, Masa-Campos, Jose L., and Ruiz-Cruz, Jorge A.
International Journal of RF and Microwave Computer-Aided Engineering. Dec 2019, Vol. 29 Issue 12, n/a
Satellite communications, Antennas (Electronics) -- Design and construction, Waveguides -- Design and construction, Sintering, 3D printing, and Computer-aided design
Keywords: additive manufacturing; fused filament fabrication; phase shifter; reconfigurable; selective laser sintering; waveguide Abstract This work presents the design and manufacturing of a K-band reconfigurable phase shifter completely implemented in waveguide technology for reduced insertion loss, good matching, and large phase shifting range. The device is based on the combination of a short slot coupler and two tunable reactive loads implemented as a section of short-circuited waveguide where an adjustable metallic post is inserted. Three prototypes of this design have been manufactured using different techniques (conventional computer numerical control machining, a low-cost fused filament fabrication technique and direct metal laser sintering) in order to assess its performance for different applications. The prototypes have been characterized experimentally and the achieved results are evaluated and compared. The proposed phase shifter, since it is fully developed in waveguide technology, eliminates the need of adding transitions to planar structures in order to integrate lumped components like pin diodes or varactors. Therefore, this device has a great potential in high-power beam steering phased arrays. Biographical information: Lucas Polo-Lopez received the BSc and MSc degrees in Telecommunication Engineering from the Universidad Autonoma de Madrid, Madrid, Spain in 2014 and 2016, respectively. Since 2015 he has been with the Radiofrequency Circuits, Antennas and Systems (RFCAS) group of this same university, where he works toward the PhD degree. His current research interests include the computer-aided design of horn antennas and passive waveguide devices, as well as the application of additive manufacturing techniques to the construction of waveguide devices. Jose L. Masa-Campos received the Master degree in 1999 and the PhD Degree in 2006, from the Universidad Politecnica de Madrid, Spain. From 1999 to 2003 he developed his professional activity in the R&D department of the company RYMSA with the design of base station antennas for mobile communications and satellite antennas. From 2002 to 2003 he directed the R&D department of RYMSA. From 2003 to 2007, he worked as Researcher for Universidad Politecnica de Madrid, and in 2005 he joined to Universidad Autonoma de Madrid as Associate Professor in the Radiofrequency Circuits, Antennas and Systems (RFCAS) group. His main current research interests are in active and passive planar array antennas. Jorge A. Ruiz-Cruz received the Ingeniero de Telecomunicacion degree and the PhD degree from the Universidad Politecnica de Madrid, Madrid, Spain, in 1999 and 2005, respectively. Since 2006, he has been with the Universidad Autonoma de Madrid, Madrid, where he became an Associate Professor in 2009. His current research interests include the computer-aided design of microwave passive devices and circuits (filters, multiplexers, and orthomodes). Byline: Lucas Polo-Lopez,Jose L. Masa-Campos,Jorge A. Ruiz-Cruz
Byline: Mohamed Farid Shehab, Nabila Mohammed Abdel Hamid, Nevien Abdullatif Askar, Ahmed Mokhtar Elmardenly Keywords: CAD-CAM, electron beam melting; immediate mandibular reconstruction; patient-specific titanium mesh; rapid prototyping Abstract Background Immediate mandibular reconstruction was performed using a patient-specific titanium mesh tray fabricated by electron beam melting (EBM) /rapid prototyping techniques. Methods Patient-specific titanium trays were virtually designed and fabricated using EBM technology/rapid prototyping for patients requiring mandibular resection and immediate reconstruction using an iliac crest bone graft. Dental implants were placed in the grafted sites and the patients received prosthetic rehabilitation with a follow-up of one year. Clinical data, postoperative bone formation and complications were evaluated. Results A symmetric appearance of facial contours was achieved. The titanium tray incorporated the particulate iliac crest bone graft that provided significant bone formation (mean 18.97 [+ or -] 1.45 mm) and predictable results. Stability of the dental implants was achieved. Conclusion The patient-specific titanium meshes and immediate particulate autogenous bone graft showed satisfactory clinical and surgical results in improving patients' quality of life and decreasing the overall treatment time with adequate functional rehabilitation.
Dorozynski, Przemyslaw, Jamroz, Witold, Wegiarz, Wladyslaw P., Kulinowski, Wojciech, Zaborowski, Mateusz, and Kulinowski, Piotr
Dissolution Technologies. Nov 2018, Vol. 25 Issue 4, p48, 6 p.
3D printing and Testing equipment
INTRODUCTION The number of studies concerning application of three dimensional (3D) printing techniques in pharmaceutical technology has grown continuously since 2005, but the main interest in application of these techniques [...] Purpose of the research was to assess feasibility of fused deposition techniques (3D printing) for development of analytical equipment dedicated for specific dosage forms and for nonstandard applications. Dissolution profiles as well as 3D magnetic resonance imaging (MRI) of the buccal tablets during hydration in dissolution medium were analyzed. The principal result of the study was the first working example of rapid 3D prototyping of dedicated, MRI-compatible dissolution equipment for mucoadhesive buccal tablets. Rapid prototyping techniques were found to be a fast, inexpensive way to develop a dedicated dissolution testing setup. KEYWORDS: additive manufacturing, 3D printing, solid free-form fabrication, buccal bioadhesive tablets, 3D ultrashort echo time magnetic resonance imaging (3D UTE MRI), pharmaceutical dissolution testing equipment
Computer Applications in Engineering Education. Nov 2015, Vol. 23 Issue 6, p947, 12 p.
Rapid prototyping and College teachers
Byline: Michele Basso, Giacomo Innocenti Keywords: LEGO Mindstorms; Simulink; Robotic laboratory; rapid prototyping; bicycle ABSTRACT LEGO.sub.[c] Mindstorms is a widely spread affordable education robotic platform, that has recently gained native support from the Mathworks.sub.[c] simulation environment Simulink. The pros and cons of the integrated Mindstorms/Simulink framework are actually illustrated through a complex model based control design project featuring a self-stabilized bicycle, that represents a proper example of the rapid prototyping capability of the platform. The importance of such an integration is discussed taking into account the history and the results of the LEGO-based learning activities held at the Control Systems Laboratory of the University of Florence for graduate and undergraduate courses. [c] 2015 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:947-958, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21666 Biographical information: Michele Basso received the Master's degree in electronic engineering from the University of Florence, Italy, in 1992, and the PhD degree in systems engineering from the University of Bologna, Italy, in 1997. From 1998 through 2010, he was an assistant professor at the Dipartimento di Sistemi e Informatica, University of Florence. Currently he is an associate professor at Dipartimento di Ingegneria dell'Informazione, University of Florence. He is also affiliated to the Center for Research on Complex Dynamics (CSDC) and a member of the Advisory Board of the Italian Ph.D. School of Information Engineering. He was an Associate Editor for the journal Communications in Nonlinear Science and Numerical Simulations from 2010 through 2014. His current research interests include nonlinear dynamical systems, scanning probe microscopy, and control education. Giacomo Innocenti graduated in 2004 in Computer Science at the Engineering School of University of Florence, Italy and in 2008 received the PhD in 'Nonlinear Dynamics and Complex Systems' from the same institution. He has been Postdoctoral Research Fellow and Adjunct Lecturer at University of Florence and at University of Siena. Since 2012 he has been Assistant Professor in Automatic Controls at University of Florence, where he teaches Industrial Automation to graduate students of the Engineering School. His scientific interests regard Nonlinear Control Systems and their practical applications.