The development of multi-channel inkjet printing methodologies for fine art applications

This thesis contributes to the defence of the practitioner perspective as a means of undertaking problems addressed predominantly in the field of colour science. Whilst artists have been exploring the use of colour for centuries through their personal practice and education, the rise of industrialised printing processes has generated a shift in focus away from these creative pursuits and into the computational field of colour research. It is argued here that the disposition and knowledge generated by creative practice has significant value to offer developing technologies. While creative practice has limited influence in the development of colour printing, practitioners and users of technology actively engage with the process in ways that extend beyond its intended uses in order to overcome recognised shortcomings. Here consideration is given to this creative engagement as motivation to develop bespoke printing parameters that demonstrate the effects of colour mixing through methods alternative to standard workflows. The research is undertaken incorporating both qualitative and quantitative analysis, collecting data from visual assessments and by examining spectral measurements taken from printed output. Action research is employed to directly access and act upon the constant developments in the art and science disciplines related to inkjet printing, observing and engaging with current methods and techniques employed by practitioners and developers. This method of research has strongly informed the empirical testing that has formed this thesis’s contribution to fine art inkjet printing practice. The research follows a practitioner led approach to designing and testing alternative printing methods and is aimed at expanding the number of discernible colours an inkjet printer can reproduce. The application of this methodology is evidenced through demonstrative prints and a reproduction study undertaken at the National Gallery, London. The experimentation undertaken in partnership with the National Gallery has proven the ability to increase accuracy between colour measured from the original target and reproduction, beyond the capabilities of current inkjet printing workflows

Developed in collaboration with and endorsed by the Heart Rhythm Society (HRS), the American College of Cardiology (ACC), the American Heart Association (AHA), and the Association for European Paediatric and Congenital Cardiology (AEPC). Endorsed by the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS).

AbstractIn view of the increasing complexity of both cardiovascular implantable electronic devices (CIEDs) and patients in the current era, practice guidelines, by necessity, have become increasingly specific. This document is an expert consensus statement that has been developed to update and further delineate indications and management of CIEDs in pediatric patients, defined as ≤21 years of age, and is intended to focus primarily on the indications for CIEDs in the setting of specific disease categories. The document also highlights variations between previously published adult and pediatric CIED recommendations and provides rationale for underlying important differences. The document addresses some of the deterrents to CIED access in low- and middle-income countries and strategies to circumvent them. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by class of recommendation and level of evidence. Several questions addressed in this document either do not lend themselves to clinical trials or are rare disease entities, and in these instances recommendations are based on consensus expert opinion. Furthermore, specific recommendations, even when supported by substantial data, do not replace the need for clinical judgment and patient-specific decision-making. The recommendations were opened for public comment to Pediatric and Congenital Electrophysiology Society (PACES) members and underwent external review by the scientific and clinical document committee of the Heart Rhythm Society (HRS), the science advisory and coordinating committee of the American Heart Association (AHA), the American College of Cardiology (ACC), and the Association for European Paediatric and Congenital Cardiology (AEPC). The document received endorsement by all the collaborators and the Asia Pacific Heart Rhythm Society (APHRS), the Indian Heart Rhythm Society (IHRS), and the Latin American Heart Rhythm Society (LAHRS). This document is expected to provide support for clinicians and patients to allow for appropriate CIED use, appropriate CIED management, and appropriate CIED follow-up in pediatric patients

An evaluation of the transferability of Munsell's colour notation methodology to modern inkjet printing technology

© 2015 SPIE. This paper examines the transferability of the Munsell system to modern inkjet colorants and printing technology following a similar approach to his original methods. While extensive research and development has gone into establishing methods for measuring and modelling the modern colour gamut, this study seeks to reintegrate the psychophysical and artistic principles used in Munsell's early colour studies with digital print. Contemporary inkjet printing, with ink sets containing a greater number of primary colorants, are significantly higher in chroma compared to the limited colorants available at the time of Munsell's original work. Following Munsell's design and implementation, our experiments replicate the use of Clerk-Maxwell's spinning disks in order to examine the effects of colour mixing with these expanded colour capacities, and to determine hue distribution and placement. This work revisits Munsell's project in light of known issues, and formulates questions about how we can reintegrate Munsell's approach for colour description and mixing into modern colour science, understanding, and potential application

Estimating neugebauer primaries for multi-channel spectral printing modeling

Multichannel printer modeling has been an active area of research in the field of spectral printing. The most commonly used models for characterization of such systems are the spectral Neugebauer (SN) and its extensions. This work addresses issues that can arise during calibration and testing of the SN model when modelling a 7-colorant printer. Since most substrates are limited in their capacity to take in large amount of ink, it is not always possible to print all colorant combinations necessary to determine the Neugebauer primaries (NP). A common solution is to estimate the nonprintable Neugebauer primaries from the single colorant primaries using the Kubelka-Munk (KM) optical model. In this work we test whether a better estimate can be obtained using general radiative transfer theory, which better represents the angular variation of the reflectance from highly absorbing media, and takes surface scattering into account. For this purpose we use the DORT2002 model. We conclude DORT2002 does not offer significant improvements over KM in the estimation of the NPs, but a significant improvement is obtained when using a simple surface scattering model. When the estimated primaries are used as inputs to the SN model instead of measured ones, it is found the SN model performs the same or better in terms of color difference and spectral error. If the mixed measured and estimated primaries are used as inputs to the SN model, it performs better than using either measured or estimated. © 2014 SPIE-IS & T

Variations in cardiac implantable electronic device surveillance and ancillary testing in the paediatric and congenital heart disease population: An international multi-centre survey from the Paediatric and Congenital Electrophysiology Society

Background: Expert guidance from scientific societies and regulatory agencies recommend a framework of principles for frequency of in-person evaluations and remote monitoring for patients with cardiac implantable electronic devices. However, there are limited data regarding adherence to recommendations among paediatric electrophysiologists, and there are no data regarding cardiac implantable electronic device-related ancillary testing. Methods: To assess current clinical practices for cardiac implantable electronic device in-person evaluation, remote monitoring, and cardiac implantable electronic device-related ancillary testing, the Paediatric and Congenital Electrophysiology Society members were surveyed. The main outcome measures were variations in frequency of in person evaluation, frequency of remote monitoring, and cardiac implantable electronic device-related ancillary testing. Results: All respondents performed in-person evaluation at least once a year, but \u3c50% of respondents performed an in-person evaluation within 2 weeks of cardiac implantable electronic device implantation. Remote monitoring was performed every 3 months for pacemakers and implantable cardioverter defibrillators by 71 and 75% respondents, respectively. Follow-up echocardiography was performed every 2-3 years by 53% respondents for patients with \u3e50% ventricular pacing. Majority of respondents (75%) did not perform either an exercise stress test or ambulatory Holter monitoring or chest X-ray (65%) after cardiac implantable electronic device implantation. Conclusion: This survey identified significant practice variations in cardiac implantable electronic device in- person evaluation, remote monitoring, and ancillary testing practices among paediatric electrophysiologists. Cardiac implantable electronic device management may be optimised by development of a paediatric-specific guidelines for follow-up and ancillary testing