4,406 research outputs found
Mobile heritage practices. Implications for scholarly research, user experience design, and evaluation methods using mobile apps.
Mobile heritage apps have become one of the most popular means for audience
engagement and curation of museum collections and heritage contexts. This
raises practical and ethical questions for both researchers and practitioners, such
as: what kind of audience engagement can be built using mobile apps? what are
the current approaches? how can audience engagement with these experience
be evaluated? how can those experiences be made more resilient, and in turn
sustainable? In this thesis I explore experience design scholarships together with
personal professional insights to analyse digital heritage practices with a view to
accelerating thinking about and critique of mobile apps in particular. As a result,
the chapters that follow here look at the evolution of digital heritage practices,
examining the cultural, societal, and technological contexts in which mobile
heritage apps are developed by the creative media industry, the academic
institutions, and how these forces are shaping the user experience design
methods. Drawing from studies in digital (critical) heritage, Human-Computer
Interaction (HCI), and design thinking, this thesis provides a critical analysis of
the development and use of mobile practices for the heritage. Furthermore,
through an empirical and embedded approach to research, the thesis also
presents auto-ethnographic case studies in order to show evidence that mobile
experiences conceptualised by more organic design approaches, can result in
more resilient and sustainable heritage practices. By doing so, this thesis
encourages a renewed understanding of the pivotal role of these practices in the
broader sociocultural, political and environmental changes.AHRC REAC
TANDEM: taming failures in next-generation datacenters with emerging memory
The explosive growth of online services, leading to unforeseen scales, has made modern datacenters highly prone to failures. Taming these failures hinges on fast and correct recovery, minimizing service interruptions.
Applications, owing to recovery, entail additional measures to maintain a recoverable state of data and computation logic during their failure-free execution. However, these precautionary measures have
severe implications on performance, correctness, and programmability, making recovery incredibly challenging to realize in practice.
Emerging memory, particularly non-volatile memory (NVM) and disaggregated memory (DM), offers a promising opportunity to achieve fast recovery with maximum performance. However, incorporating these technologies into datacenter architecture presents significant challenges; Their distinct architectural attributes, differing significantly from traditional memory devices, introduce new semantic challenges for
implementing recovery, complicating correctness and programmability.
Can emerging memory enable fast, performant, and correct recovery in the datacenter? This thesis aims to answer this question while addressing the associated challenges.
When architecting datacenters with emerging memory, system architects face four key challenges: (1) how to guarantee correct semantics; (2) how to efficiently enforce correctness with optimal performance; (3) how to validate end-to-end correctness including recovery; and (4) how to preserve programmer productivity (Programmability).
This thesis aims to address these challenges through the following approaches: (a)
defining precise consistency models that formally specify correct end-to-end semantics
in the presence of failures (consistency models also play a crucial role in programmability); (b) developing new low-level mechanisms to efficiently enforce the prescribed models given the capabilities of emerging memory; and (c) creating robust testing frameworks to validate end-to-end correctness and recovery.
We start our exploration with non-volatile memory (NVM), which offers fast persistence capabilities directly accessible through the processor’s load-store (memory) interface. Notably, these capabilities can be leveraged to enable fast recovery for Log-Free Data Structures (LFDs) while maximizing performance. However, due to the complexity of modern cache hierarchies, data hardly persist in any specific order, jeop-
ardizing recovery and correctness. Therefore, recovery needs primitives that explicitly control the order of updates to NVM (known as persistency models). We outline the precise specification of a novel persistency model – Release Persistency (RP) – that provides a consistency guarantee for LFDs on what remains in non-volatile memory upon failure. To efficiently enforce RP, we propose a novel microarchitecture mechanism,
lazy release persistence (LRP). Using standard LFDs benchmarks, we show that LRP achieves fast recovery while incurring minimal overhead on performance.
We continue our discussion with memory disaggregation which decouples memory from traditional monolithic servers, offering a promising pathway for achieving very high availability in replicated in-memory data stores. Achieving such availability hinges on transaction protocols that can efficiently handle recovery in this setting, where
compute and memory are independent. However, there is a challenge: disaggregated memory (DM) fails to work with RPC-style protocols, mandating one-sided transaction protocols. Exacerbating the problem, one-sided transactions expose critical low-level
ordering to architects, posing a threat to correctness. We present a highly available transaction protocol, Pandora, that is specifically designed to achieve fast recovery in disaggregated key-value stores (DKVSes).
Pandora is the first one-sided transactional protocol that ensures correct, non-blocking, and fast recovery in DKVS. Our experimental implementation artifacts demonstrate that Pandora achieves fast recovery and high availability while causing minimal disruption to services.
Finally, we introduce a novel target litmus-testing framework – DART – to validate the end-to-end correctness of transactional protocols with recovery. Using DART’s target testing capabilities, we have found several critical bugs in Pandora, highlighting the need for robust end-to-end testing methods in the design loop to iteratively fix correctness bugs. Crucially, DART is lightweight and black-box, thereby eliminating
any intervention from the programmers
Displacement and the Humanities: Manifestos from the Ancient to the Present
This is the final version. Available on open access from MDPI via the DOI in this recordThis is a reprint of articles from the Special Issue published online in the open access journal Humanities (ISSN 2076-0787) (available at: https://www.mdpi.com/journal/humanities/special_issues/Manifestos Ancient Present)This volume brings together the work of practitioners, communities, artists and other researchers from multiple disciplines. Seeking to provoke a discourse around displacement within and beyond the field of Humanities, it positions historical cases and debates, some reaching into the ancient past, within diverse geo-chronological contexts and current world urgencies. In adopting an innovative dialogic structure, between practitioners on the ground - from architects and urban planners to artists - and academics working across subject areas, the volume is a proposition to: remap priorities for current research agendas; open up disciplines, critically analysing their approaches; address the socio-political responsibilities that we have as scholars and practitioners; and provide an alternative site of discourse for contemporary concerns about displacement. Ultimately, this volume aims to provoke future work and collaborations - hence, manifestos - not only in the historical and literary fields, but wider research concerned with human mobility and the challenges confronting people who are out of place of rights, protection and belonging
Digital agriculture: research, development and innovation in production chains.
Digital transformation in the field towards sustainable and smart agriculture. Digital agriculture: definitions and technologies. Agroenvironmental modeling and the digital transformation of agriculture. Geotechnologies in digital agriculture. Scientific computing in agriculture. Computer vision applied to agriculture. Technologies developed in precision agriculture. Information engineering: contributions to digital agriculture. DIPN: a dictionary of the internal proteins nanoenvironments and their potential for transformation into agricultural assets. Applications of bioinformatics in agriculture. Genomics applied to climate change: biotechnology for digital agriculture. Innovation ecosystem in agriculture: Embrapa?s evolution and contributions. The law related to the digitization of agriculture. Innovating communication in the age of digital agriculture. Driving forces for Brazilian agriculture in the next decade: implications for digital agriculture. Challenges, trends and opportunities in digital agriculture in Brazil
Development of standardised sizing system and size charts for the production of ready-to-wear clothing for Ghanaian children aged 6-11
Children experience rapid growth rate and often indulge in various physical and motion related activities in education and play spaces. Ill-fitting clothing such as very tight or unproportionally balanced clothes can cause movement restrictions, psychological challenges, and other undesirable health related issues. This makes appropriate clothing sizing crucial to address, as it gives children the right fit that allows room for movement and growth.
Effectiveness of fit is based on a sizing system and size charts that have been developed using current and accurate body measurements of a specific population since differences exist among populations. Currently, established size charts and academic publications on sizing systems in Ghana have focused on women. No national database or anthropometric study has been developed exclusively for Ghanaian children. Practitioners either take measurements on ad-hoc basis for made-to-measure outfits; or use adapted versions of the British sizing system for manufacturing ready-to-wear garments such as uniforms. This research has therefore been undertaken to develop a standard clothing sizing system and size charts for Ghanaian children between the (school) ages of 6 and 11. This will sustain the general production of reliably sized garments for Ghanaian children whiles providing appropriate fit. It will further enhance mass production of ready-to-wear garments for the apparel market in Ghana.
The study involved both secondary and primary data collection methods. An extensive review of literature was conducted focusing on relevant topics in anthropometry and anthropometric surveys for sizing creation, sizing systems, growth of children and garment fit. A comprehensive set of body measurements including height and weight of the sample population of school children were collected. A critical measurement procedural guide and two instructional videos in English and Twi (dominant Ghanaian language) were developed by the study taking into account efficacy, ethical and sustainable considerations for good practice. These were made available and guided parents/legal guardians and participants in the data collection process during fieldwork. The population consisted of primary school pupils in Ghana. A sample of 776 usable data was used for the analysis. With the IBM SPSS analytics software, appropriate statistical procedures such as means, t-test and analysis of variance tests (ANOVA) were conducted to ascertain the relationships among the variables and to obtain statistical data for the development of the sizing system. Principal component analysis (PCA) and cluster analysis were also used to aid the development of the sizing system. Centred on the PCA technique, three key dimensions (height, chest, and waist girths) were selected based on the factor loading and practicality. The study found and established significant differences between the body measurements of Ghanaian children aged 6-11 along gender lines. Using the cluster analysis technique, the selected dimensions were used to categorize the study sample into homogenous subgroups according to upper and lower body separately for both males and females. Four or five sizes were created for each cluster group, and size charts were established based on percentile values.
This study presents theoretical and empirical contributions to the body of knowledge in anthropometrics. It has modelled a guide that demonstrates the capability of remote and safe body measuring practices on children, which is particularly useful, economical, and reliable for clothing related practices that seek to employ consistent traditional manual measuring techniques. The study has created an original up-to-date anthropometric database for Ghanaian children between 6-11 years; and developed a comprehensive sizing system for wider clothing practices. In addition to providing a framework for procedures in creating children’s sizing system and size chart, it establishes new size charts for both males and females aged 6-11, based on the Ghanaian population. These developments stand to increase productivity, consistency, and economic efficiency for the Ghanaian apparel industry. The study makes recommendations for extending this work to other segments of the population
Resilient cooling of buildings: state of the art review
Name of the research project : IEA Annex 80 – Resilient Cooling of Buildings
Publisher: Institute of Building Research & Innovation ZT GmbH, AustriaThis report summarizes an assessment of current State-of-the Art resilient cooling strategies and technologies. It is a result of a collaborative work conducted by participants members of IEA EBC Annex 80. This report consists of four chapters.
In the first chapter are included relevant technologies and strategies that contribute to reducing heat loads to people and indoor environments. These technologies/strategies include Advanced window/glazing and shading technologies, Cool envelope materials, Evaporative Envelope Surfaces, Ventilated Envelope Surfaces and Heat Storage and Release.
In the second chapter are assessed cooling strategies and technologies that are responsible for removing sensible heat in indoor environments: Ventilative cooling, Evaporative Cooling, Compression refrigeration, Desiccant cooling system, Ground source cooling, Night sky radiative cooling and High-temperature cooling systems.
In the third chapter various typologies of cooling strategies and technologies are assessed inside the framework of enhancing personal comfort apart from space cooling. This group of strategies/technologies comprise of: Vertical-axis ceiling fans and horizontal-axis wall fans (such fixed fans differ from pure PCS in that they may be operated under imposed central control or under group or individual control), Small desktop-scale fans or stand fans, Furnitureintegrated fan jets, Devices combining fans with misting/evaporative cooling, Cooled chairs, with convective/conductive cooled heat absorbing surfaces, Cooled desktop surfaces,
Workstation micro-air-conditioning units, some including phase change material storage, Radiantly cooled panels (these are currently less for PCS than for room heat load extraction), Conductive wearables, Fan-ventilated clothing ensembles, Variable clothing insulation: flexible dress codes and variable porosity fabrics.
In the fourth chapter technologies and strategies pertinent to removing latent heat from indoor environments are assessed. This group includes Desiccant dehumidification, Refrigeration dehumidification, Ventilation dehumidification, and Thermos-electric dehumidification.Preprin
Nonlinear Spectroscopy for Characterizing Cells, Proteins, and the Origins of the Photobiomodulation Effect
The introduction of the laser in the 1960s brough forth the discovery of many nonlinear phenomena and marked the beginning of the field of nonlinear optics. Nonlinear spectroscopy offers many additional features over conventional linear spectroscopy which can be useful towards biomedical applications. In this work, we employ nonlinear spectroscopy and phenomena towards solving problems in biomedical fields.
In the first study, the visible light generation following filamentation is studied to address knowledge gaps within the American National Standard for the Safe Use of Lasers (ANSI Z136.1-2014). The ANSI standards provide maximum permissible exposure (MPE) values for skin and retinal tissue; however, nonlinear optical effects that cause visible light generation are currently not addressed. In this study, we measure the visible light following filamentation of ultrafast near- to mid- infrared (IR) light. Near-IR light, which normally attenuates before reaching the retina in the eye, was found to generate sufficient visible light following filamentation to exceed the MPE values set by ANSI.
In the next two studies, ultrafast transient absorption spectroscopy is used to study the mechanisms underlying the photobiomodulation (PBM) effect. PBM is the use of low irradiance light in the red to near-IR range to stimulate beneficial effects in tissues and cells. However, the electronic or molecular mechanisms which initiate that effect are not well understood. In our first study, we introduce a novel methodology which couples a continuous wave (CW) laser with ultrafast transient absorption spectroscopy (TAS), coined as CW-TAS, and test the proof-of-principle with the mitochondrial protein, cytochrome c (Cyt c). The TAS data for Cyt c remained intact and unperturbed with the addition of the CW light compared to standard TAS. This indicated that CW-TAS can be used on the more complex mitochondrial proteins suspected to be involved in PBM, and it provided further evidence that Cyt c was not an initiator of the PBM effect. In our second study, we apply the CW-TAS technique to the more complex mitochondrial protein, Complex III (C-III), from a mammalian source. This study provided the first TAS characterization for C-III from specifically a mammalian source. In addition, the photodissociation and recombination of the axial ligand that was tested with TAS was found to not exhibit changes when measured with CW-TAS. Therefore, we conclude that this electronic process of C-III is eliminated from being a potential initiator of the PBM effect.
In the final study, beam shaping techniques were applied to improve the spectral resolution of impulsive stimulated Brillouin scattering (ISBS) spectroscopy towards cellular studies. Brillouin spectroscopy, which studies the elastic properties of materials, has been demonstrated to be useful for biomedical imaging and sensing. In particular, ISBS microscopy has recently been introduced towards biomedical applications; however, improvements to the spectral resolution have not been currently addressed. In this study, we expand the initial pump beam diameter with a 4f configuration and employ the use of a cylindrical lens to focus it into the system. The ISBS linewidth in the Fourier domain was found to be dependent on the pump beam’s spatial geometry. By increasing the spectral resolution, close elastic signals can be resolved which is important in biological and cellular studies where samples contain a high water content
Investigation of Ground Deformations and Vibrations Due to Impact Pile Driving: Measurements and Prediction Model
Pile driving, a commonly used method for installing deep foundations, has gained prominence as a foundation solution to transfer structural loads to deep competent strata. However, this method of installation can generate noise, ground vibrations, and deformations. These effects pose risks to adjacent structures and buried utilities, jeopardizing the safety and serviceability of urban infrastructure. Researchers and public and private agencies have proposed many vibration limit criteria to avoid damage to infrastructure. However, these criteria for construction vibrations are not linked to the ground densification associated with repetitive and cumulative loadings in sandy soils. This dissertation focuses on developing a prediction semi-empirical model to determine ground deformations and vibrations induced by impact pile driving in granular soil deposits. Field data of ground deformations and vibrations were collected by monitoring 13 project sites in Central Florida during the installation of precast prestressed concrete piles using impact hammers. A continuous pile driving modeling approach, in which the pile is driven without any interruption to a final target depth, was coupled with an Updated Lagrangian approach in the numerical framework. An advanced constitutive soil model (i.e., hypoplasticity for sands enhanced with the intergranular strain concept) capable of reproducing changes in the soil void ratio during pile driving was adopted by computationally matching the nonlinear behavior of the granular layer with published shear modulus degradation curves. A critical highly disturbed zone was defined due to the computed soil liquefaction. The developed prediction model is validated with field data, previously published vibration attenuation curves, and vibration-induced ground surface settlement prediction methods in terms of its ability to estimate ground vibrations and deformations induced by impact pile driving in this study. Semi-empirical equations and charts are proposed using a combination of field measurements and numerical analyses to consider the following variables for the ground response due to impact pile driving operations: (1) rated energy of the hammer, (2) scaled distance from the pile, (3) pre-drilling depth, and (4) soil relative void ratio, which is related to relative density. The findings indicated that large ground deformations can occur even in cases where vibration levels (i.e., peak particle velocities) do not exceed the vibration limits
Towards a Peaceful Development of Cyberspace - Challenges and Technical Measures for the De-escalation of State-led Cyberconflicts and Arms Control of Cyberweapons
Cyberspace, already a few decades old, has become a matter of course for most of us, part of our everyday life. At the same time, this space and the global infrastructure behind it are essential for our civilizations, the economy and administration, and thus an essential expression and lifeline of a globalized world. However, these developments also create vulnerabilities and thus, cyberspace is increasingly developing into an intelligence and military operational area – for the defense and security of states but also as a component of offensive military planning, visible in the creation of military cyber-departments and the integration of cyberspace into states' security and defense strategies. In order to contain and regulate the conflict and escalation potential of technology used by military forces, over the last decades, a complex tool set of transparency, de-escalation and arms control measures has been developed and proof-tested. Unfortunately, many of these established measures do not work for cyberspace due to its specific technical characteristics. Even more, the concept of what constitutes a weapon – an essential requirement for regulation – starts to blur for this domain. Against this background, this thesis aims to answer how measures for the de-escalation of state-led conflicts in cyberspace and arms control of cyberweapons can be developed. In order to answer this question, the dissertation takes a specifically technical perspective on these problems and the underlying political challenges of state behavior and international humanitarian law in cyberspace to identify starting points for technical measures of transparency, arms control and verification. Based on this approach of adopting already existing technical measures from other fields of computer science, the thesis will provide proof of concepts approaches for some mentioned challenges like a classification system for cyberweapons that is based on technical measurable features, an approach for the mutual reduction of vulnerability stockpiles and an approach to plausibly assure the non-involvement in a cyberconflict as a measure for de-escalation. All these initial approaches and the questions of how and by which measures arms control and conflict reduction can work for cyberspace are still quite new and subject to not too many debates. Indeed, the approach of deliberately self-restricting the capabilities of technology in order to serve a bigger goal, like the reduction of its destructive usage, is yet not very common for the engineering thinking of computer science. Therefore, this dissertation also aims to provide some impulses regarding the responsibility and creative options of computer science with a view to the peaceful development and use of cyberspace
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