Benefits of using modern cementing techniques in the acetabulum : the rim cutter

Purpose. To compare radiological records of 90 consecutive patients who underwent cemented total hip arthroplasty (THA) with or without use of the Rim Cutter to prepare the acetabulum. Methods. The acetabulum of 45 patients was prepared using the Rim Cutter, whereas the device was not used in the other 45 patients. Postoperative radiographs were evaluated using a digital templating system to measure (1) the positions of the operated hips with respect to the normal, contralateral hips (the centre of rotation of the socket, the height of the centre of rotation from the teardrop, and lateralisation of the centre of rotation from the teardrop) and (2) the uniformity and width of the cement mantle in the 3 DeLee Charnley acetabular zones, and the number of radiolucencies in these zones. Results. The study group showed improved radiological parameters and were closer to the anatomic centre of rotation both vertically (1.5 vs. 3.7 mm, p<0.001) and horizontally (1.8 vs. 4.4 mm, p<0.001) and had consistently thicker and more uniform cement mantles (p<0.001). There were 2 radiolucent lines in the control group but none in the study group. Conclusion. The Rim Cutter resulted in more accurate placement of the centre of rotation of a cemented prosthetic socket, and produced a thicker, more congruent cement mantle with fewer radiolucent lines.

The naturally imperfect form : investigations of the application of digital sculpting methods - extracted art : incorporating and translating ‘found art’ into the medium of digital sculpture

This dissertation analyses how physical objects are translated into digital artworks using techniques which can lead to ‘imperfections’ in the resulting digital artwork that are typically removed to arrive at a ‘perfect’ final representation. The dissertation discusses the adaptation of existing techniques into an artistic workflow that acknowledges and incorporates the imperfections of translation into the final pieces. It presents an exploration of the relationship between physical and digital artefacts and the processes used to move between the two. The work explores the 'craft' of digital sculpting and the technology used in producing what the artist terms ‘a naturally imperfect form’, incorporating knowledge of traditional sculpture, an understanding of anatomy and an interest in the study of bones (Osteology). The outcomes of the research are presented as a series of digital sculptural works, exhibited as a collection of curiosities in multiple mediums, including interactive game spaces, augmented reality (AR), rapid prototype prints (RP) and video displays.

Digital social signal processing - theorectical underpinning and research agenda

Organizations make increasingly use of social media in order to compete for customer awareness and improve the quality of their goods and services. Multiple techniques of social media analysis are already in use. Nevertheless, theoretical underpinnings and a sound research agenda are still unavailable in this field at the present time. In order to contribute to setting up such an agenda, we introduce digital social signal processing (DSSP) as a new research stream in IS that requires multi-facetted investigations. Our DSSP concept is founded upon a set of four sequential activities: sensing digital social signals that are emitted by individuals on social media; decoding online data of social media in order to reconstruct digital social signals; matching the signals with consumers’ life events; and configuring individualized goods and service offerings tailored to the individual needs of customers. We further contribute to tying loose ends of different research areas together, in order to frame DSSP as a field for further investigation. We conclude with developing a research agenda.

Indigenous/digital heterogeneities : an actor-network-theory approach

This thesis analysed the theoretical and ontological issues of previous scholarship concerning information technology and indigenous people. As an alternative, the thesis used the framework of actor-network-theory, especially through historiographical and ethnographic techniques. The thesis revealed an assemblage of indigenous/digital enactments striving for relevance and avoiding obsolescence. It also recognised heterogeneities- including user-ambivalences, oscillations, noise, non-coherences and disruptions - as part of the milieu of the daily digital lives of indigenous people. By taking heterogeneities into account, the thesis ensured that the data “speaks for itself” and that social inquiry is not overtaken by ideology and ontology.

Developing cultural responsiveness in environmental design students through digital storytelling and photovoice

As the Latino population in the United States grows, it will become increasingly important for undergraduate students in environmental design and related disciplines to become more culturally responsive and learn how to understand and address challenges faced by population groups, such as Latino youth. To this end, we involved environmental design undergraduate students at the University of Colorado in a service-learning class to mentor Latino youth in the creation of multimedia narratives using photovoice and digital storytelling techniques. The introduction of technology was used as a bridge between the two groups and to provide a platform for the Latino youth to reveal their community experiences. Based on focus group results, we describe the impact on the undergraduate students and provide recommendations for similar programs that can promote cultural responsiveness through the use of digital technology and prepare environmental design students to work successfully in increasingly diverse communities.

Digital tablets as a tool for blended learning in power engineering education

Digital tablets have been identified as a tool for enabling blended learning and supporting online teaching and learning. A small scale trial was undertaken to assess the effectiveness of this technology when applied to power engineering education. Critical findings and experiences gained from this trial, including potential benefits, presentation techniques and the resulting student feedback are presented in this paper.

Digital image databases support GIS operations

Evaluates trends in the imagery built into GIS applications to supplement existing vector data of streets, boundaries, infrastructure and utilities. These include large area digital orthophotos, Landsat and SPOT data. Future developments include 3 to 5 metre pixel resolutions from satellites, 1 to 2 metres from aircraft. GPS and improved image analysis techniques will also assist in improving resolution and accuracy.

Authenticating Multicast Streams in Lossy Channels Using Threshold Techniques

We first classify the state-of-the-art stream authentication problem in the multicast environment and group them into Signing and MAC approaches. A new approach for authenticating digital streams using Threshold Techniques is introduced. The new approach main advantages are in tolerating packet loss, up to a threshold number, and having a minimum space overhead. It is most suitable for multicast applications running over lossy, unreliable communication channels while, in same time, are pertain the security requirements. We use linear equations based on Lagrange polynomial interpolation and Combinatorial Design methods.

Evaluation of resonant damping techniques for Z-source current-type inverter

For the renewable energy sources whose outputs vary continuously, a Z-source current-type inverter has been proposed as a possible buck-boost alternative for grid-interfacing. With a unique X-shaped LC network connected between its dc power source and inverter topology, Z-source current-type inverter is however expected to suffer from compounded resonant complications in addition to those associated with its second-order output filter. To improve its damping performance, this paper proposes the careful integration of Posicast or three-step compensators before the inverter pulse-width modulator for damping triggered resonant oscillations. In total, two compensators are needed for wave-shaping the inverter boost factor and modulation ratio, and they can conveniently be implemented using first-in first-out stacks and embedded timers of modern digital signal processors widely used in motion control applications. Both techniques are found to damp resonance of ac filter well, but for cases of transiting from current-buck to boost state, three-step technique is less effective due to the sudden intermediate discharging interval introduced by its non-monotonic stepping (unlike the monotonic stepping of Posicast damping). These findings have been confirmed both in simulations and experiments using an implemented laboratory prototype.

Applying academagogy : the transference of an organised heuristic teaching approach to the digital realm

Much has been written about transferring class materials and teaching techniques to digital platforms, but less has been written about applying heuristic organizing constructs in the same manner. With the transformation of learning ecologies over the past decades as well as requirements to adjust to constantly shifting digital tools and environments, the challenges for learning facilitators are to readily adapt and change, as well as to engage a changing learner demographic. However, most importantly is to engage most effectively with learners in these online environments. This article reviews the existing literature in the heuristic construct of academagogy [1] and applies a case study methodology to discussion of the first application of academagogy to the online delivery of an undergraduate design unit. Through a focus on effective teaching and learning techniques, the transfer from face-to-face (f2f) to the digital realm is explored through four main focal points: Tools for teaching, teaching and learning, communicating with students, and effective teaching methods. These four focal points are then used to discuss ways to meet the challenges of teaching online including how they create new dimensions in teaching practice and how the digital experience changes learning experiences. The article concludes with reflection and consolidation of the similarities and differences between the face-to-face and digital deliveries, and by suggesting changes to the academagogic heuristic to enable its use more easily in a digital space.

From ideation to sculpture : digital sculpting as the primary 'ideation' tool for creature design

This research project examined the potential for circumventing drawing in the ideation process by adopting digital sculpture as the primary conceptual development and design tool for the digital sculpting of creature designs. Through a series of experimental research cycles, multiple frameworks were explored with the aim of identifying a methodology for creating '3D sculpted sketches' for the initial phases of the ideation process. This research project acknowledges that drawing still remains the predominant method of visualising design ideas for characters and creatures for many artists. However, alongside other ideation techniques digital sculpting can function as a rapid and responsive tool to visualize and explore forms in a digital sculpting environment for the conceptualisation of multiple creature design variations. The results of this study are significant for emerging digital sculptors who may not necessarily have a well-defined creative brief or initial concept.

Digital innovation in social marketing: A systematic literature of interventions using digital channels for engagement

Social marketing uses commercial marketing techniques to deliver interventions for social benefit in order to improve quality of life for individuals and communities. Behaviour change is the primary objective of social marketing interventions (Andreasen 2002). The aim of this systematic review is to provide insight into social marketing interventions and their evaluations published in peer-reviewed journals so as to identify the key elements of social marketing employed by these interventions. as well as understand the use of digital channels for engagement.

Detecting the attributes of a wheat crop using digital imagery acquired from a low-altitude platform

A low-altitude platform utilising a 1.8-m diameter tethered helium balloon was used to position a multispectral sensor, consisting of two digital cameras, above a fertiliser trial plot where wheat (Triticum spp.) was being grown. Located in Cecil Plains, Queensland, Australia, the plot was a long-term fertiliser trial being conducted by a fertiliser company to monitor the response of crops to various levels of nutrition. The different levels of nutrition were achieved by varying nitrogen application rates between 0 and 120 units of N at 40 unit increments. Each plot had received the same application rate for 10 years. Colour and near-infrared images were acquired that captured the whole 2 ha plot. These images were examined and relationships sought between the captured digital information and the crop parameters imaged at anthesis and the at-harvest quality and quantity parameters. The statistical analysis techniques used were correlation analysis, discriminant analysis and partial least squares regression. A high correlation was found between the image and yield (R2 = 0.91) and a moderate correlation between the image and grain protein content (R2 = 0.66). The utility of the system could be extended by choosing a more mobile platform. This would increase the potential for the system to be used to diagnose the causes of the variability and allow remediation, and/or to segregate the crop at harvest to meet certain quality parameters.

A dual-slope analogue-to-digital converter for generating polynomials

A new digital polynomial generator using the principle of dual-slope analogue-to-digital conversion is proposed. Techniques for realizing a wide range of integer as well as fractional coefficients to obtain the desired polynomial have been discussed. The suitability of realizing the proposed polynomial generator in integrated circuit form is also indicated.

Novel window functions for digital filters

Window technique is one of the simplest methods to design Finite Impulse Response (FIR) filters. It uses special functions to truncate an infinite sequence to a finite one. In this paper, we propose window techniques based on integer sequences. The striking feature of the proposed work is that it overcomes all the problems posed by floating point numbers and inaccuracy, as the sequences are made of only integers. Some of these integer window sequences, yield sharp transition, while some of them result in zero ripple in passband and stopband.