Topic
Occupancy
About: Occupancy is a research topic. Over the lifetime, 2757 publications have been published within this topic receiving 68288 citations.
Papers published on a yearly basis
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TL;DR: A broad classification of space occupancy measures into three categories that capture changes in size, density, or position is proposed, finding that no measure describes all of trait space aspects but that some are better at capturing certain aspects.
Abstract: Multidimensional analysis of traits are now common in ecology and evolution and are based on trait spaces in which each dimension summarizes the observed trait combination (a morphospace or an ecospace) Observations of interest will typically occupy a subset of this space, and researchers will calculate one or more measures to quantify how organisms inhabit that space In macroevolution and ecology, these measures called disparity or dissimilarity metrics are generalized as space occupancy measures Researchers use these measures to investigate how space occupancy changes through time, in relation to other groups of organisms, or in response to global environmental changes However, the mathematical and biological meaning of most space occupancy measures is vague with the majority of widely used measures lacking formal description Here, we propose a broad classification of space occupancy measures into three categories that capture changes in size, density, or position We study the behavior of 25 measures to changes in trait space size, density, and position on simulated and empirical datasets We find that no measure describes all of trait space aspects but that some are better at capturing certain aspects Our results confirm the three broad categories (size, density, and position) and allow us to relate changes in any of these categories to biological phenomena Because the choice of space occupancy measures is specific to the data and question, we introduced https://tguillermeshinyappsio/moms/moms, a tool to both visualize and capture changes in space occupancy for any measurement https://tguillermeshinyappsio/moms/moms is designed to help workers choose the right space occupancy measures, given the properties of their trait space and their biological question By providing guidelines and common vocabulary for space occupancy analysis, we hope to help bridging the gap in multidimensional research between ecology and evolution
37 citations
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01 Sep 2010
TL;DR: In this paper, a nonlinear Model Predictive Control (NMPC) is designed and implemented in real-time based on Dynamic Programming for indoor air temperature control in a solar decathlon house.
Abstract: Current research studies show that building heating, cooling and ventilation energy
consumption account for nearly 40% of the total building energy use in the U.S. The
potential for saving energy through building control systems varies from 5% to 20%
based on recent market surveys. In addition, building control affects environmental
performances such as thermal, visual, air quality, etc., and occupancy such as working
productivity and comfort. Building control has been proven to be important both in
design and operation stages.
Building control design and operation need consistent and reliable static and dynamic
information from multiple resources. Static information includes building geometry,
construction and HVAC equipment. Dynamic information includes zone environmental
performance, occupancy and outside weather information during operation.. At the same
time, model-based predicted control can help to optimize energy use while maintaining
indoor set-point temperature when occupied. Unfortunately, several issues in the current
approach of building control design and operation impede achieving this goal. These
issues include: a) dynamic information data such as real-time on-site weather (e.g.,
temperature, wind speed and solar radiation) and occupancy (number of occupants and
occupancy duration in the space) are not readily available; b) a comprehensive building
energy model is not fully integrated into advanced control for accuracy and robustness; c)
real-time implementation of indoor air temperature control are rare. This dissertation
aims to investigate and solve these issues based on an integrated building control
approach.
This dissertation introduces and illustrates a method for integrated building heating,
cooling and ventilation control to reduce energy consumption and maintain indoor
temperature set-point, based on the prediction of occupant behavior patterns and weather
conditions. Advanced machine learning methods including Adaptive Gaussian Process,
Hidden Markov Model, Episode Discovery and Semi-Markov Model are modified and
implemented into this dissertation. A nonlinear Model Predictive Control (NMPC) is
designed and implemented in real-time based on Dynamic Programming. The experiment
test-bed is setup in the Solar Decathlon House (2005), with over 100 sensor points
measuring indoor environmental parameters such as temperature, relative humidity, CO2,
lighting, motion and acoustics, and power consumption for electrical plugs, HVAC and
lighting. The outdoor environmental parameters, such as temperature, relative humidity,
CO2, global horizontal solar radiation and wind speed, are measured by the on-site
weather station. The designed controller is implemented through LabVIEW.
The experiments are carried out for two continuous months in the heating season and for
a week in cooling season. The results show that there is a 26% measured energy
reduction in the heating season compared with the scheduled temperature set-points, and
17.8% energy reduction in the cooling season. Further simulation-based results show that
with tighter building facade, the cooling energy reduction could reach 20%. Overall, the
heating, cooling and ventilation energy reduction could reach nearly 50% based on this
integrated control approach for the entire heating/cooling testing periods compared to the
conventional scheduled temperature set-point.
37 citations
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TL;DR: It is unlikely that species with very low phylogenetic relatedness to natives will become successful invaders with very high distribution in the area studied, and under future climate warming scenarios, present-day urban aliens of high occupancy frequency are likely to become successful invasiveness even outside urban areas.
Abstract: Aim: Understanding the processes that drive invasion success of alien species has received considerable attention in current ecological research. From an evolutionary point of view, many studies have shown that the phylogenetic similarity between the invader species and the members of the native community may be an important aspect of invasiveness. In this study, using a coarse-scale systematic sampling grid of 1 km2, we explore whether the occupancy frequency of two groups of alien species, archaeophytes and neophytes, in the urban angiosperm flora of Brussels is influenced by their phylogenetic relatedness to native species. Location: The city of Brussels (Belgium). Methods: We used ordinary least-squares regressions and quantile regressions for analysing the relationship between the occupancy frequency of alien species in the sampled grid and their phylogenetic distance to the native species pool. Results: Alien species with high occupancy frequency in the sampled grid are, on average, more phylogenetically related to native species than are less frequent aliens, although this relationship is significant only for archaeophytes. In addition, as shown by the quantile regressions, the relationship between phylogenetic relatedness to the native flora and occupancy frequency is much stronger for the most frequent aliens than for rare aliens. Main conclusions: Our data suggest that it is unlikely that species with very low phylogenetic relatedness to natives will become successful invaders with very high distribution in the area studied. To the contrary, under future climate warming scenarios, present-day urban aliens of high occupancy frequency are likely to become successful invaders even outside urban areas. © 2010 Blackwell Publishing Ltd.
37 citations
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TL;DR: In this article, the authors used Landsat data to develop maps of canopy cover for each study area, which were then used to quantify annual territory-specific habitat covariates and found that forests with medium (40-69%) and high (≥70%) canopy cover were the most important predictors of territory occupancy.
Abstract: We assessed the occupancy dynamics of 275 California Spotted Owl (Strix occidentalis occidentalis) territories in 4 study areas in the Sierra Nevada, California, USA, from 1993 to 2011. We used Landsat data to develop maps of canopy cover for each study area, which we then used to quantify annual territory-specific habitat covariates. We modeled the relationships between territory extinction and colonization using predictor variables of habitat, disturbance (logging, fire), climate, and elevation. We found that forests with medium (40–69%) and high (≥70%) canopy cover were the most important predictors of territory occupancy in all study areas, and that both canopy cover categories were positively correlated with occupancy. We used analysis of deviance to estimate the amount of variation explained by the habitat covariates (primarily medium and high canopy cover) and found that these covariates explained from 35% to 67% of the variation in occupancy. Climatic covariates were not correlated with o...
37 citations
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TL;DR: The results show life history variation can be important in determining the relative susceptibility of a species to drought conditions, and that sympatric species experiencing the same environmental conditions can respond differently.
Abstract: Drought is a strong density-independent environmental filter that contributes to population regulation and other ecological processes. Not all species respond similarly to drought, and the overall impacts can vary depending on life histories. Such differences can necessitate management strategies that incorporate information on individual species to maximize conservation success. We report the effects of a short-term drought on occupancy and reproductive success of two pond-breeding salamanders that differ in breeding phenology (fall vs. spring breeder) across an active military base landscape in Missouri, USA: We surveyed ~200 ponds for the presence of eggs, larvae, and metamorphs from 2011 to 2013. This period coincided with before, during, and after a severe drought that occurred in 2012. The two species showed contrasting responses to drought, where high reproductive failure (34% of ponds) was observed for the spring breeder during a single drought year. Alternatively, the fall breeder only showed a cumulative 8% failure over two years. The number of breeding ponds available for use in the fall decreased during the drought due to pond drying and/or a lack of re-filling. Estimates of occupancy probability declined for the fall-breeding salamander between 2012 and 2013, whereas occupancy probability estimates of the spring breeder increased post-drought. The presence of fish, hydroperiod, the amount of forest cover surrounding ponds, and canopy cover were all found to affect estimates of occupancy probabilities of each species. Pond clustering (distance to nearest pond and the number of ponds within close proximity), hydroperiod, forest cover, and canopy cover influenced both estimates of colonization and extinction probabilities. Our results show life history variation can be important in determining the relative susceptibility of a species to drought conditions, and that sympatric species experiencing the same environmental conditions can respond differently. Consideration of the spatial network and configuration of habitat patches that act as refuges under extreme environmental conditions will improve conservation efforts, such as the placement of permanent ponds for aquatic organisms. A better awareness of species-specific tolerances to environmental filters such as drought can lead to improved management recommendations to conserve and promote habitat for a greater diversity of species across landscapes of spatially connected populations.
37 citations