Efficient Irregular Wavefront Propagation Algorithms on Hybrid CPU-GPU Machines

In this paper, we address the problem of efficient execution of a computation pattern, referred to here as the irregular wavefront propagation pattern (IWPP), on hybrid systems with multiple CPUs and GPUs. The IWPP is common in several image processing operations. In the IWPP, data elements in the wavefront propagate waves to their neighboring elements on a grid if a propagation condition is satisfied. Elements receiving the propagated waves become part of the wavefront. This pattern results in irregular data accesses and computations. We develop and evaluate strategies for efficient computation and propagation of wavefronts using a multi-level queue structure. This queue structure improves the utilization of fast memories in a GPU and reduces synchronization overheads. We also develop a tile-based parallelization strategy to support execution on multiple CPUs and GPUs. We evaluate our approaches on a state-of-the-art GPU accelerated machine (equipped with 3 GPUs and 2 multicore CPUs) using the IWPP implementations of two widely used image processing operations: morphological reconstruction and euclidean distance transform. Our results show significant performance improvements on GPUs. The use of multiple CPUs and GPUs cooperatively attains speedups of 50x and 85x with respect to single core CPU executions for morphological reconstruction and euclidean distance transform, respectively.Comment: 37 pages, 16 figure

Describing Connections between Science Content and Future Careers: Implementing Texas Curriculum for Rural At-Risk High School Students Using Purposefully-Designed Field Trips

The state of Texas has an ‘essential knowledge’ component in some high school science courses indicating that students be able to describe connections between academic science content and future jobs or training through effective exposure to course content. The participants in this study were from a small rural high school in central Texas. Each was labeled as ‘at-risk’ and self-identified an inability to describe those types of connections after earning credit in more than one science course with that ‘essential knowledge’ component. A career-focused field trip to a local vocational/technology training center was designed to address that particular deficit. This study followed a narrative multiple-case case study design. Data included school records, surveys, individual and focus group interviews, and field notes from observations during the field trip. The effectiveness of the field trip was evident as each participant was able to describe connections immediately following the excursion

A disciplinary commons for database teaching

This paper discusses the experience of taking part in a disciplinary commons devoted to the teaching of database systems. It will discuss the structure of a disciplinary commons and our experience of the database version

Kinetic Model of CCA Fixation on Wood. Part III. Model Validation

In previous studies, models were developed for the initial and main fixation reactions of chromated copper arsenate (CCA-C) on red pine wood as a function of time and isothermal wood temperature conditions following treatment with 1% CCA-C. In this study, these models are used to predict the amount of fixation over sequential short non-isothermal intervals as a way of predicting time to total fixation under variable temperature conditions. The rate of fixation of CCA-C treated red pine pole sections could generally be accurately predicted, using these models, from thermocouple temperature readings in the pole surface, even under a highly variable temperature fixation regime. However, variations in fixation rate were observed even within a single pole, associated with density differences at the butts and tops of the poles. This confirms that fixation time estimates are very sensitive to the model parameters and suggests that the model may not accurately predict fixation rates over a wide range of material sources

Managing the Paradox of Growth in Brand Communities Through Social Media

The commercial benefits of online brand communities are an important focus for marketers seeking deeper engagement with increasingly elusive consumers. Managing participation in these socially bound brand conversations challenges practitioners to balance authenticity towards the community against corporate goals. This is important as social media proliferation affords communities the capacity to reach a scale well beyond their offline equivalents and to operate independently of brands. While research has identified the important elements of engagement in brand communities, less is known about how strategies required to maximise relationships in these circumstances must change with growth. Using a case study approach, we examine how a rapidly growing firm and its community have managed the challenges of a maturing relationship. We find that, in time, the community becomes self-sustaining, and a new set of marketing management strategies is required to move engagement to the next level

Brand Response to Consumer Backlash in Social Media: A Typology

The use of social media by consumers to admonish firms for their conduct has become increasingly common. Such backlash can take many forms and often occurs rapidly, spreads widely and is highly visible. The potential damage to brands can be severe if these situations are not dealt with effectively. To date, the issue has been examined relatively superficially in a range of disciplines without specific regard to the management of consumer-brand relationships in online environments. Our research examines the nature of company reactions to social media backlash and conceptualises a typology that categorises reputational damage and effective response. We present four typical reactionary scenarios and conclude that insufficient research exists in this domain proportionate to the level of consumer-brand social media discourse to the peril of practitioners operating via these channel

Managing the Paradox of Growth in Brand Communities Through Social Media

The commercial benefits of online brand communities are an important focus for marketers seeking deeper engagement with increasingly elusive consumers. Managing participation in these socially bound brand conversations challenges practitioners to balance authenticity towards the community against corporate goals. This is important as social media proliferation affords communities the capacity to reach a scale well beyond their offline equivalents and to operate independently of brands. While research has identified the important elements of engagement in brand communities, less is known about how strategies required to maximise relationships in these circumstances must change with growth. Using a case study approach, we examine how a rapidly growing firm and its community have managed the challenges of a maturing relationship. We find that, in time, the community becomes self-sustaining, and a new set of marketing management strategies is required to move engagement to the next level

Domains of Influence: Exploring Negative Sentiment in Social Media

Purpose The purpose of this study is to empirically examine the manner in which companies mitigate negative sentiment in social media and to map the forces that may lead to pre-emptive strategies. Design/methodology/approach Case studies were drawn from the retail fashion industry using data collected from semi-structured, in-depth interviews with practitioners and a netnographic examination of company artefacts and social media conversations. Findings The findings identify five principal domains of influence upon which the firms based their approach to social media negativity. The authors suggest that these domains can be fundamentally categorised as either relational domains built on human exchanges or transformational domains rooted in less tangible elements of corporate culture and operational practices that can have a significant impact upon a brand’s socially mediated exchanges. Practical implications The research provides guidance based on empirical observation of effective strategies utilised by firms, emphasising robust systems integration, a holistic management ethos, and leveraging of third-party alliances. Originality/value Bringing together disparate cross-disciplinary elements, the research contributes to knowledge by highlighting opportunities for the development of a proactive rather than reactive approach to online brand negativity and deepens the understanding of applied brand management techniques adopted to address negative social media encounters. The authors provide a series of contemporary and empirically grounded recommendations for practitioners that offer substantive insights