537,119 research outputs found
Social presence and dishonesty in retail
Self-service checkouts (SCOs) in retail can benefit consumers and retailers, providing control and autonomy to shoppers independent from staff, together with reduced queuing times. Recent research indicates that the absence of staff may provide the opportunity for consumers to behave dishonestly, consistent with a perceived lack of social presence. This study examined whether a social presence in the form of various instantiations of embodied, visual, humanlike SCO interface agents had an effect on opportunistic behaviour. Using a simulated SCO scenario, participants experienced various dilemmas in which they could financially benefit themselves undeservedly. We hypothesised that a humanlike social presence integrated within the checkout screen would receive more attention and result in fewer instances of dishonesty compared to a less humanlike agent. This was partially supported by the results. The findings contribute to the theoretical framework in social presence research. We concluded that companies adopting self-service technology may consider the implementation of social presence in technology applications to support ethical consumer behaviour, but that more research is required to explore the mixed findings in the current study.<br/
A heuristic approach for the allocation of resources in large-scale computing infrastructures
An increasing number of enterprise applications are intensive in their consumption of IT, but are infrequently used. Consequently, organizations either host an oversized IT infrastructure or they are incapable of realizing the benefits of new applications. A solution to the challenge is provided by the large-scale computing infrastructures of Clouds and Grids which allow resources to be shared. A major challenge is the development of mechanisms that allow efficient sharing of IT resources. Market mechanisms are promising, but there is a lack of research in scalable market mechanisms. We extend the Multi-Attribute Combinatorial Exchange mechanism with greedy heuristics to address the scalability challenge. The evaluation shows a trade-off between efficiency and scalability. There is no statistical evidence for an influence on the incentive properties of the market mechanism. This is an encouraging result as theory predicts heuristics to ruin the mechanism’s incentive properties. Copyright © 2015 John Wiley & Sons, Ltd
From Bare Metal to Virtual: Lessons Learned when a Supercomputing Institute Deploys its First Cloud
As primary provider for research computing services at the University of
Minnesota, the Minnesota Supercomputing Institute (MSI) has long been
responsible for serving the needs of a user-base numbering in the thousands.
In recent years, MSI---like many other HPC centers---has observed a growing
need for self-service, on-demand, data-intensive research, as well as the
emergence of many new controlled-access datasets for research purposes. In
light of this, MSI constructed a new on-premise cloud service, named Stratus,
which is architected from the ground up to easily satisfy data-use agreements
and fill four gaps left by traditional HPC. The resulting OpenStack cloud,
constructed from HPC-specific compute nodes and backed by Ceph storage, is
designed to fully comply with controls set forth by the NIH Genomic Data
Sharing Policy.
Herein, we present twelve lessons learned during the ambitious sprint to take
Stratus from inception and into production in less than 18 months. Important,
and often overlooked, components of this timeline included the development of
new leadership roles, staff and user training, and user support documentation.
Along the way, the lessons learned extended well beyond the technical
challenges often associated with acquiring, configuring, and maintaining
large-scale systems.Comment: 8 pages, 5 figures, PEARC '18: Practice and Experience in Advanced
Research Computing, July 22--26, 2018, Pittsburgh, PA, US
A Generic Approach for Escaping Saddle points
A central challenge to using first-order methods for optimizing nonconvex
problems is the presence of saddle points. First-order methods often get stuck
at saddle points, greatly deteriorating their performance. Typically, to escape
from saddles one has to use second-order methods. However, most works on
second-order methods rely extensively on expensive Hessian-based computations,
making them impractical in large-scale settings. To tackle this challenge, we
introduce a generic framework that minimizes Hessian based computations while
at the same time provably converging to second-order critical points. Our
framework carefully alternates between a first-order and a second-order
subroutine, using the latter only close to saddle points, and yields
convergence results competitive to the state-of-the-art. Empirical results
suggest that our strategy also enjoys a good practical performance
Silicate rock weathering and atmospheric/soil CO2 uptake in the Amazon basin estimated from river water geochemistry: seasonal and spatial variations
Using the data of the CAMREX project (1982–1984) on the water geochemistry of the Amazon river and its main
tributaries, it was possible to assess the silicate rock weathering processes and the associated consumption of atmospheric/soil CO2, taking into account seasonal and spatial variations. This study confirms the important role of the Andes in the fluvial transport of dissolved and particulate material by the Amazon, and it shows for the first time that the silicate weathering rate and atmospheric/soil CO2 consumption are higher in the Andes than in the rest of the Amazon basin. The seasonal variations exhibit the significant role of runoff as a major factor controlling silicate weathering processes and
show that the chemical erosion rates vary greatly from low discharge to high discharge. The average weathering rate estimated for the whole Amazon basin (15 m/My) is comparable to other estimations made for other tropical–equatorial environments. A comparison between physical and chemical weathering rates of silicate rocks for the Amazon basin and for each tributary basin show that in the Andes and in the Amazon trough, the soil thicknesses are decreasing whereas in the Shield the soil profiles are
deepening
"Modelling Sustainable International Tourism Demand to the Brazilian Amazon"
The Amazon rainforest is one of the world's greatest natural wonders and holds great importance and significance for the world's environmental balance. Around 60% of the Amazon rainforest is located in the Brazilian territory. The two biggest states of the Amazon region are Amazonas (the upper Amazon) and Para (the lower Amazon), which together account for around 73% of the Brazilian Legal Amazon, and are the only states that are serviced by international airports in Brazil's North region. The purpose of this paper is to model and forecast sustainable international tourism demand for the states of Amazonas, Para, and the aggregate of the two states. By sustainable tourism is meant a distinctive type of tourism that has relatively low environmental and cultural impacts. Economic progress brought about by illegal wood extraction and commercial agriculture has destroyed large areas of the Amazon rainforest. The sustainable tourism industry has the potential to contribute to the economic development of the Amazon region without destroying the rainforest. The paper presents unit root tests for monthly and annual data, estimates alternative time series models and conditional volatility models of the shocks to international tourist arrivals, and provides forecasts for 2006 and 2007.
Modelling Sustainable International Tourism Demand to the Brazilian Amazon
The Amazon rainforest is one of the world’s greatest natural wonders and holds great importance and significance for the world’s environmental balance. Around 60% of the Amazon rainforest is located in the Brazilian territory. The two biggest states of the Amazon region are Amazonas (the upper Amazon) and Pará (the lower Amazon), which together account for around 73% of the Brazilian Legal Amazon, and are the only states that are serviced by international airports in Brazil’s North region. The purpose of this paper is to model and forecast sustainable international tourism demand for the states of Amazonas, Pará, and the aggregate of the two states. By sustainable tourism is meant a distinctive type of tourism that has relatively low environmental and cultural impacts. Economic progress brought about by illegal wood extraction and commercial agriculture has destroyed large areas of the Amazon rainforest. The sustainable tourism industry has the potential to contribute to the economic development of the Amazon region without destroying the rainforest. The paper presents unit root tests for monthly and annual data, estimates alternative time series models and conditional volatility models of the shocks to international tourist arrivals, and provides forecasts for 2006 and 2007.Brazilian Amazon; International Tourism Demand; Time Series Modelling; Conditional Volatility Models; Forecasting.
Modelling sustainable international tourism demand to the Brazilian Amazon
The Amazon rainforest is one of the world’s greatest natural wonders and holds great importance and significance for the world’s environmental balance. Around 60% of the Amazon rainforest is located in the Brazilian territory. The two biggest states of the Amazon region are Amazonas (the upper Amazon) and Pará (the lower Amazon), which together account for around 73% of the Brazilian Legal Amazon, and are the only states that are serviced by international airports in Brazil’s North region. The purpose of this paper is to model and forecast sustainable international tourism demand for the states of Amazonas, Pará, and the aggregate of the two states. Economic progress of the region has been achieved at a cost of destroying large areas of the Amazon rain forest. In this scenario, the tourism industry would seem to have the potential to contribute to sustainable economic development in the North region of Brazil. The paper presents unit root tests for monthly and annual data, estimates alternative time series models and conditional volatility models of the shocks to international tourist arrivals, and provides forecasts for 2006 and 2007.forecasting;conditional volatility models;Brazilian Amazon;international tourism demand;time series modelling
Migration and forests in the Peruvian Amazon: a review
This paper reviews the literature on the links between migration and forests in the Peruvian Amazon. It highlights
not only the complexity of the migrant–forest interface in Peru but also the relative lack of research on these
dynamics. Historically, official narratives point to migrants as both the culprits of, and solutions to, the Amazon’s problems. At times, the government has promoted colonization of the Amazon as a means to integrate the region into the country as well as to encourage agricultural expansion and alleviate pressure on limited land in the Andes. In other periods, migrants are blamed for deforestation and environmental degradation in the region. These discourses oversimplify the complexity of the reality facing migrants to the Amazon and the factors that ‘push’ them away from their birthplaces and/or ‘pull’ them to the Amazon. They also treat migrants as a homogenous
group, underestimating: the role of migration within the Amazon, the cyclical nature of migration, processes of
urbanization and multi-site households, and the diversity of livelihoods migrants pursue upon arrival. A more
detailed understanding of migrants, migration and the related conditions and processes driving human mobility
in the Amazon should provide a more effective foundation for defining public policy in the region, for example,
for the identification of strategies to mitigate the impacts of road construction or to support sustainable models of production in areas occupied by smallholder farm families. This review is intended as a step toward a fuller
understanding of these processes by compiling existing information as a point of departure
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