scholarly journals First description of underwater acoustic diversity in three temperate ponds

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1393 ◽  
Author(s):  
Camille Desjonquères ◽  
Fanny Rybak ◽  
Marion Depraetere ◽  
Amandine Gasc ◽  
Isabelle Le Viol ◽  
...  
Keyword(s):  
Signal To Noise Ratio ◽  
Control Variable ◽  
Large Data ◽  
Diversity Indices ◽  
Song Type ◽  
Data Set ◽  
Partial Correlations ◽  
Acoustic Diversity ◽  
High Level

The past decade has produced an increased ecological interest in sonic environments, or soundscapes. However, despite this rise in interest and technological improvements that allow for long-term acoustic surveys in various environments, some habitats’ soundscapes remain to be explored. Ponds, and more generally freshwater habitats, are one of these acoustically unexplored environments. Here we undertook the first long term acoustic monitoring of three temperate ponds in France. By aural and visual inspection of a selection of recordings, we identified 48 different sound types, and according to the rarefaction curves we calculated, more sound types are likely present in one of the three ponds. The richness of sound types varied significantly across ponds. Surprisingly, there was no pond-to-pond daily consistency of sound type richness variation; each pond had its own daily patterns of activity. We also explored the possibility of using six acoustic diversity indices to conduct rapid biodiversity assessments in temperate ponds. We found that all indices were sensitive to the background noise as estimated through correlations with the signal-to-noise ratio (SNR). However, we determined that theARindex could be a good candidate to measure acoustic diversities using partial correlations with the SNR as a control variable. Yet, research is still required to automatically compute the SNR in order to apply this index on a large data set of recordings. The results showed that these three temperate ponds host a high level of acoustic diversity in which the soundscapes were variable not only between but also within the ponds. The sources producing this diversity of sounds and the drivers of difference in daily song type richness variation both require further investigation. Such research would yield insights into the biodiversity and ecology of temperate ponds.

scholarly journals Introducing the Dynamic Destination Satisfaction Method: An Analytical Tool to Track Tourism Destination Satisfaction Trends with Repeated Cross-sectional Data

2020 ◽  
pp. 004728752095820
Author(s):  
Andrea Guizzardi ◽  
Marcello M. Mariani
Keyword(s):  
Large Data ◽  
System Level ◽  
Set Covering ◽  
Tourism Destination ◽  
Cross Sectional ◽  
Data Set ◽  
Individual Level ◽  
Specific Attribute ◽  
The Matrix

This study introduces a new method, named Dynamic Destination Satisfaction Method (DDSME), to model tourists’ satisfaction with a destination (and its attributes), breaking it down into an individual-level component (linked to the specific individual tourists’ perceptions) and a system-level (time-related) component (common to all the tourists). Moreover, this work develops a matrix “entropy/trend accuracy” that destination managers can use to understand to what extent managing a specific attribute has increased tourists’ satisfaction with the destination over multiyear time spans. We test the innovative method on a large data set, covering the period 1997-2015 and including almost 0.8 million observations. By doing so, we analyze tourists’ satisfaction with tourism-related sectors and attributes of Italy as an inbound tourism destination and we use the matrix to map out destination attributes over time. The findings indicate that courtesy, art, and food are strategic attributes to enhance satisfaction in the long term.

Investigating sponsor decision-making: the role of schema theory, agency conflicts, and signaling theory in the persistence of naming rights agreements

2020 ◽  
Vol 21 (3) ◽  
pp. 467-486 ◽  
Author(s):  
Jonathan A. Jensen ◽  
David Head ◽  
Christopher Mergy
Keyword(s):  
Decision Making ◽  
Schema Theory ◽  
Agency Conflicts ◽  
Data Set ◽  
Content Type ◽  
Naming Rights ◽  
High Level ◽  
Sport Facilities

PurposeNaming rights sponsorships of sport facilities are among the most highly visible marketing agreements in the world. However, factors that may lead one sponsorship to persist for decades, while others end after just a few years, have yet to be investigated. Thus, this study examines the decision-making of brand marketers by investigating the predictors of a sponsoring brand's decision to either continue or dissolve such agreements.Design/methodology/approachUtilizing a global data set of 219 naming rights agreements, an empirical approach is utilized to isolate whether a variety of factors increase or decrease the probability of sponsorship dissolution.FindingsResults indicate that agreements entered into with new, as of yet-unnamed facilities lead to a reduction in the probability of dissolution, with a high level of brand equity also reducing the probability of dissolution. Agency conflicts may also play a role, as the sponsoring firm being headquartered in the same metropolitan area as the facility also contributes to the persistence of such agreements.Originality/valueThese results are intended to assist both sides of what is ideally a long-term relationship in better understanding the factors that may either contribute to or inhibit longer-term partnerships.

scholarly journals An improved NO<sub>2</sub> retrieval for the GOME-2 satellite instrument

2011 ◽  
Vol 4 (6) ◽  
pp. 1147-1159 ◽  
Author(s):  
A. Richter ◽  
M. Begoin ◽  
A. Hilboll ◽  
J. P. Burrows
Keyword(s):  
Signal To Noise Ratio ◽  
Bare Soil ◽  
Satellite Observations ◽  
Spectral Signature ◽  
Data Set ◽  
Good Consistency ◽  
The Individual ◽  
High Pass

Abstract. Satellite observations of nitrogen dioxide (NO2) provide valuable information on both stratospheric and tropospheric composition. Nadir measurements from GOME, SCIAMACHY, OMI, and GOME-2 have been used in many studies on tropospheric NO2 burdens, the importance of different NOx emissions sources and their change over time. The observations made by the three GOME-2 instruments will extend the existing data set by more than a decade, and a high quality of the data as well as their good consistency with existing time series is of particular importance. In this paper, an improved GOME-2 NO2 retrieval is described which reduces the scatter of the individual NO2 columns globally but in particular in the region of the Southern Atlantic Anomaly. This is achieved by using a larger fitting window including more spectral points, and by applying a two step spike removal algorithm in the fit. The new GOME-2 data set is shown to have good consistency with SCIAMACHY NO2 columns. Remaining small differences are shown to be linked to changes in the daily solar irradiance measurements used in both GOME-2 and SCIAMACHY retrievals. In the large retrieval window, a not previously identified spectral signature was found which is linked to deserts and other regions with bare soil. Inclusion of this empirically derived pseudo cross-section significantly improves the retrievals and potentially provides information on surface properties and desert aerosols. Using the new GOME-2 NO2 data set, a long-term average of tropospheric columns was computed and high-pass filtered. The resulting map shows evidence for pollution from several additional shipping lanes, not previously identified in satellite observations. This illustrates the excellent signal to noise ratio achievable with the improved GOME-2 retrievals.

scholarly journals Exploring the role of hydrological pathways in modulating multi-annual climate teleconnection periodicities from UK rainfall to streamflow

2021 ◽  
Vol 25 (4) ◽  
pp. 2223-2237
Author(s):  
William Rust ◽  
Mark Cuthbert ◽  
John Bloomfield ◽  
Ron Corstanje ◽  
Nicholas Howden ◽  
...  
Keyword(s):  
North Atlantic ◽  
Response Times ◽  
Large Data ◽  
Data Set ◽  
The North ◽  
South Wales ◽  
The North Atlantic ◽  
The North Atlantic Oscillation ◽  
The Uk

Abstract. An understanding of multi-annual behaviour in streamflow allows for better estimation of the risks associated with hydrological extremes. This can enable improved preparedness for streamflow-dependant services, such as freshwater ecology, drinking water supply and agriculture. Recently, efforts have focused on detecting relationships between long-term hydrological behaviour and oscillatory climate systems (such as the North Atlantic Oscillation – NAO). For instance, the approximate 7 year periodicity of the NAO has been detected in groundwater-level records in the North Atlantic region, providing potential improvements to the preparedness for future water resource extremes due to their repetitive, periodic nature. However, the extent to which these 7-year, NAO-like signals are propagated to streamflow, and the catchment processes that modulate this propagation, are currently unknown. Here, we show statistically significant evidence that these 7-year periodicities are present in streamflow (and associated catchment rainfall), by applying multi-resolution analysis to a large data set of streamflow and associated catchment rainfall across the UK. Our results provide new evidence for spatial patterns of NAO periodicities in UK rainfall, with areas of greatest NAO signal found in southwest England, south Wales, Northern Ireland and central Scotland, and show that NAO-like periodicities account for a greater proportion of streamflow variability in these areas. Furthermore, we find that catchments with greater subsurface pathway contribution, as characterised by the baseflow index (BFI), generally show increased NAO-like signal strength and that subsurface response times (as characterised by groundwater response time – GRT), of between 4 and 8 years, show a greater signal presence. Our results provide a foundation of understanding for the screening and use of streamflow teleconnections for improving the practice and policy of long-term streamflow resource management.

Computing Gamma Calculus on Computer Cluster

2012 ◽  
pp. 2016-2026
Author(s):  
Hong Lin ◽  
Jeremy Kemp ◽  
Padraic Gilbert
Keyword(s):  
Gpu Computing ◽  
Programming Model ◽  
Large Data ◽  
General Purpose ◽  
Tuple Space ◽  
Data Set ◽  
Cuda Architecture ◽  
High Level ◽  
General Purpose Gpu ◽  
Grid Cluster

Gamma Calculus is an inherently parallel, high-level programming model, which allows simple programming molecules to interact, creating a complex system with minimum of coding. Gamma calculus modeled programs were written on top of IBM’s TSpaces middleware, which is Java-based and uses a “Tuple Space” based model for communication, similar to that in Gamma. A parser was written in C++ to translate the Gamma syntax. This was implemented on UHD’s grid cluster (grid.uhd.edu), and in an effort to increase performance and scalability, existing Gamma programs are being transferred to Nvidia’s CUDA architecture. General Purpose GPU computing is well suited to run Gamma programs, as GPU’s excel at running the same operation on a large data set, potentially offering a large speedup.

Parametric Uncertainty and Fat Tails

2012 ◽  
Author(s):  
Christian Gollier
Keyword(s):  
Economic Growth ◽  
Extreme Events ◽  
Growth Process ◽  
Parametric Uncertainty ◽  
Large Data ◽  
Limited Data ◽  
Data Set ◽  
Low Probability ◽  
The One

This chapter shows how the probability distribution for economic growth is subject to some parametric uncertainty. There is a limited data set for the dynamics of economic growth, and the absence of a sufficiently large data set to estimate the long-term growth process of the economy implies that its parameters are uncertain and subject to learning in the future. This problem is particularly crucial when its parameters are unstable, or when the dynamic process entails low-probability extreme events. Thus, the rarer the event, the less precise the estimate of its likelihood. This builds a bridge between the problem of parametric uncertainty, and the one of extreme events.

scholarly journals User perceptions of long-term costs and benefits of MDMA use: Findings from a large online sample

2021 ◽  
Author(s):  
James Elsey ◽  
Vivi Anna Felicia Wuestman ◽  
Anouk Fieten
Keyword(s):  
Online Survey ◽  
Drug Effects ◽  
Large Data ◽  
Future Research ◽  
Long Term Effects ◽  
Negative Effects ◽  
Data Set ◽  
User Perceptions ◽  
Wide Range

Background. Previous research has focused largely on risks associated with non-clinical (‘recreational’) MDMA use. Potential benefits produced through MDMA-assisted psychotherapy raise the question whether recreational users might report some positive long-term effects of MDMA use.Aim. 1) To assess the perceptions of recreational MDMA users regarding a wide range of both positive and negative long-term effects of MDMA use. 2) To generate a large data set including other correlates of interest to highlight targets for future research. Methods. Eight-hundred and eighty-six MDMA users gave valid responses to an online survey, covering perceived long-term effects, acute and subacute effects, use motivations, contexts of use, and polydrug use. We present descriptive results for motivations, acute, subacute, and long-term effects, and exploratory relationships between long-term effects and these variables.Results. User perceptions of MDMA’s long-term effects were far more positive than negative, with a positive overarching perspective on having used MDMA and endorsement of several more specific effects. Negative/unpleasant acute and subacute effects of MDMA use were positively related to negative long-term effects. Positive/pleasant acute and subacute effects were positively related to positive long-term effects. User motivations were also significantly associated with perceived long-term effects. A minority of users reported negative effects (e.g., on concentration/memory and mood), which should not be ignored.Conclusions. Factors beyond the anticipation of a short-term high likely play into many users’ decisions to use MDMA. A nuanced understanding of user perceptions can inform drug safety communication, our understanding of drug effects, and drug policy.

Detecting and Characterizing Archetypes of Unintended Consequences in Engineered Systems

2020 ◽  
Author(s):  
Hannah S. Walsh ◽  
Andy Dong ◽  
Irem Y. Tumer ◽  
Guillaume Brat
Keyword(s):  
Risk Factors ◽  
Large Data ◽  
Unintended Consequences ◽  
Adverse Outcomes ◽  
Lessons Learned ◽  
Human Machine Interaction ◽  
Data Set ◽  
Engineered Systems ◽  
High Level ◽  
Machine Interaction

Abstract When designing engineered systems, the potential for unintended consequences of design policies exists despite best intentions. The effect of risk factors for unintended consequences are often known only in hindsight. However, since historical knowledge is generally associated with a single event, it is difficult to uncover general trends in the formation and types of unintended consequences. In this research, archetypes of unintended consequences are learned from historical data. This research contributes toward the understanding of archetypes of unintended consequences by using machine learning over a large data set of lessons learned from adverse events at NASA. Sixty-six archetypes are identified because they share similar sets of risk factors such as complexity and human-machine interaction. To validate the learned archetypes, system dynamics representations of the archetypes are compared to known high-level archetypes of unintended consequences. The main contribution of the paper is a set of archetypes that apply to many engineered systems and a pattern of leading indicators that open a new path to manage unintended consequences and mitigate the magnitude of potentially adverse outcomes.

scholarly journals Heavy negative ion growth in Titan’s polar winter

2019 ◽  
Vol 490 (2) ◽  
pp. 2254-2261
Author(s):  
A Wellbrock ◽  
A J Coates ◽  
G H Jones ◽  
V Vuitton ◽  
P Lavvas ◽  
...  
Keyword(s):  
Negative Ions ◽  
Large Data ◽  
Solar Flux ◽  
Negative Ion ◽  
Seasonal Effects ◽  
Unexpected Result ◽  
Data Set ◽  
Cassini Mission ◽  
First Time

ABSTRACT A significant but unexpected result of the Cassini mission was the discovery of heavy organic negative ions in Titan’s ionosphere at altitudes between about 950 and 1400 km by the CAPS Electron Spectrometer (ELS). The heaviest ions were observed during the T16 fly-by with masses over 13 000 u/q. This is significantly higher than the maximum masses observed during other fly-bys. We study T16 CAPS-ELS observations and examine the evolution of mass spectra at different altitudes. We also study maximum mass trends using a large data set from all available CAPS-ELS observations of the Cassini mission in order to investigate the conditions necessary to allow negative ions to grow to the highest masses. For the first time, we are able to investigate the relationship between the highest mass particles and seasonal effects. We find that the combination of high latitude and winter conditions, resulting in long-term restricted solar flux, create an environment in which ion growth can reach the highest masses, as observed during T16. Restricting solar flux long term, and hence photodestruction reactions such as photodetachment, appears to be essential for negative ions to grow beyond 10 000 u/q.

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