This article presents an approach to determining the smallest number of coefficients of a Parallel Hammerstein (PH) model to reduce the development complexity of wideband RF power amplifiers' (PA) modeling and predistortion schemes. The visualization of the impulse responses of the different filters of the PH yields a systematic and single-iteration approach for determining the optimal modeling structure, for example, filters' lengths. The approach was used to determine an optimal structure that linearizes the response of a 400-watt LDMOS Doherty PA driven with a four carrier WCDMA signal. In the experiments conducted, the number of coefficients in the PH was reduced by about a factor of 2.5 without compromising its modeling and linearization performance. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:116–118, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25660

This paper expounds a complexity-reduced Volterra series model for radio frequency power amplifier (PA) behavioral modeling and digital predistortion (DPD). An analysis was conducted, which took into account the memory effect mechanisms of the PA. This led to a closed-form expression that relates the memoryless behavior of the PA to the finite impulse response feedback filter, which approximates the memory effects’ behavior. The analysis resulted in a complexity-reduced Volterra series model which allows for a substantial reduction in the requirements for digital signal processors and the time needed to construct and implement the DPD in a real-time environment. The proposed model was validated as a behavioral model and a DPD using two different PA architectures, employing two different transistor technologies, driven by both 20 MHz 1001 wideband code division multiple access and long term evolution signals. The results obtained demonstrate the excellent modeling and linearization c...

Over the past decade the outdoor play spaces designed for children in Canada have been largely shaped by fear and profit, rather than by what we know about children's play and development. Since the early 1980s the Canadian Standards Association (CSA) has played an increasingly important role in this transformation as their technical standards for children's outdoor play spaces have been gradually adapted as policy by local and regional agencies. While the CSA has historically regulated industrial and commercial projects that enable international trade and harmonization with countries such as the United States, their extension of influence to early childhood is problematic; particularly when applied to childcare centres. The following describes some of the issues that arise from the use of safety standards as policy, and the problems these standards cause when applied to childcare centres.

Computer dependent design space is illustrated with the recent international competition project for Kowloon Arts Center. The spatial condition of design resulted from the deployment of Euclidian geometry and use of the nonrational, complex surfaces. Another aspect of computer dependent space was rooted in the contemporary work situation where architects located on the three different continents collaborated in distributed mode over the internet. The resulting project confirms the creative potential of the above aspects of the digital space in contemporary design.

Distributed design over networks is rapidly emerging as the new mode of architectural practice. Recent digital working environment of virtual studio is illustrated with three case studies. Projects highlight the social importance and advocate remote delivery of studio education and design practice in the sheared digital space.

In the final years of the millennium and following the rapid dissemination of computing, we are witnessing the global expansion of the internet. In architecture, the connectivity over this “mother of all networks” is becoming an integral part of design practice and design education. This connectivity can be seen both as an instrument for communication and for the remediation of past conventions. Geographically and temporally distributed design collaboration is illustrated and discussed in this paper as a new condition for making architecture both in terms of limits and opportunities. Furthermore, this paper reports on recent long-distance design collaborations and their impact on the nature of contemporary practice. The authors have attempted to utilize the Virtual Design Studio (VDS) method in a professional context. This method of architectural design is based upon experimental work which began in the early 1990s, primarily in an academic context [A]. It was named the Virtual Desi...

Computer dependent design space is illustrated with the recent international competition project for Kowloon Arts Center. The spatial condition of design resulted from the deployment of Euclidian geometry and use of the non-rational, complex surfaces. Another aspect of computer dependent space was rooted in the contemporary work situation where architects located on the three different continents collaborated in distributed mode over the internet. The resulting project confirms the creative potential of the above aspects of the digital space in contemporary design.

Contemporary architecture can be seen as a dynamic system that changes in response to its environment and even as a system that can modify itself. Interactive or responsive environments are not totally new to architecture; however, the possibilities in architecture have only begun to be examined.To look at the possibilities in this emerging field experimentation is required and the architect must develop an understanding of the language of sensors, actuators and control systems.This article examines an interdisciplinary design research studio with mechatronic engineers which allowed a wide range of experimentation. It shows that the scope of what can be done with responsive architecture is hard to imagine from where we now stand and that it is only through a broad range of experimentation that we can find the most beneficial uses of this powerful technology.The resulting projects-kinetic architecture on control systems-challenge our understanding of what our built environment could be.

Although a right-sided aortic arch is not a rare anomaly, an aortic dissection involving an isolated right-sided aortic arch is extremely rare and remains a complicated entity for surgical therapy because of its anatomical characteristics. Previous reports that we have identi®ed in English literature include only six surgical cases of aortic dissection involving a right-sided aortic arch. We report on a 75-year-old female who had a chronic thoracoabdominal aortic aneurysm following type B aortic dissection in a right-sided aortic arch. Graft replacement including reconstruction of Adamkiewicz artery and a celiac trunk was performed. The postoperative course was uneventful except for a prolonged ventilatory support. This case seems to be the ®rst successful case of extended graft replacement for this pathology.

The need for architects to develop their own computational tools is becoming increasingly evident. In this paper, we introduced our design tool named ‘UVN generator’ which is based on the algorithmic process combining scripting potentiality and flexibility of traditional 3D surface modeling. Our attempt on combining the two served us well to explore the new ground for design. New conditions were explored and observed in the three case studies which are named ‘on a surface’, ‘between surfaces’ and ‘on a new ordered surface’, referring to place where the scripts were run. In design projects presented in our case studies, we focus on the system behind the generation of complex, expressive, biomimetic, yet humanistic shape. This challenge to find a new ground for computational design enables us to pose our critical question ‘What could be algorithmic design potential may lay beyond basic surfaces?’.

Technological development generates social changes while providing new tools that can be implemented in the fields of architecture and urban design. It creates the need to enrich architects’ competencies with knowledge and experience, enabling the conscious use of technology in designing future functional solutions for responsive space and the optimization of accessibility for various groups of users. This paper presents a teaching method developed to study the integration of architecture, urban planning and mechatronics to create a dynamic common space, responding to changing user needs and environmental conditions. Four experimental projects for a chosen public space were designed by students in order to investigate research by design and as an agenda for further design research. In the final part of the article, we present predictions for the future development of kinetic and responsive architecture in public spaces, including potential opportunities and challenges.

The idea of the Bauhaus education was born out of the conviction that designs for mass production and modern architecture needed a new fundamental design strategy. Today, seventy-five years later, the modern, basic design pedagogy needs to be revisited, as the impact of the Information Technology Revolution on design practice and education is now extensive. The illustrations and reflections on a modern curriculum for fundamental design and communication presented in this paper are derived from the authors' introduction of the new media to design studios at UBC and from design practice. In the case of the nascent student of architecture, a different, rudimentary approach is required: one calling for the combining of the modern, basic design agenda with the introduction of the new media. The fundamental digital design pedagogy is young and not fully established. This is a considerable problem, since the practice and learning of architecture today is increasingly aided by and dependent upon digital media. Parallel to the traditional methods, the contemporary student of design is now obliged to engage new and dynamic conditions at the formative stage of his or her education. In the recent past, the computer was considered as just another device, requiring the development of mechanical techniques or skills. While those skills still have to be mastered, more recently in design education and practice, IT has become accepted as MEDIA-not just as a drafting or modeling tool. This process is perhaps due to the rapid dissemination of computing literacy and to the progressive accessibility and ease of use of IT. At UBC, Techniques and the Foundation Studio are introductory courses intended to make students engage the new media in parallel with, and complimentary to, established conventions in design.

The future of urban infrastructure is no doubt a future of control systems. An architecture that engages infrastructure can engage control systems to not only improve efficiency and mediate contested urban space but also to modifying spaces for different uses, buffer environmental factors and respond to occupation or use. The use of mechatronics in architecture requires interdisciplinary collaboration and an understanding of control systems, sensors and actuators. Through a theoretical project, research and a design studio, this paper discusses the future of mechatronics in architecture and shows the huge potential for reimagining our infrastructure. The application to the infrastructural realm pushes the design out of the scope of conventional architecture both in the use of mechatronics and its application to the larger realm of the city.