Occupancy

About: Occupancy is a research topic. Over the lifetime, 2757 publications have been published within this topic receiving 68288 citations.

Occupancy measurement in commercial office buildings for demand-driven control applications

Abstract: Commercial office buildings represent the largest in floor area in most developed countries and utilize substantial amount of energy in the provision of building services to satisfy occupants’ comfort needs. This makes office buildings a target for occupant-driven demand control measures, which have been demonstrated as having huge potential to improve energy efficiency. The application of occupant-driven demand control measures in buildings, most especially in the control of thermal, visual and indoor air quality providing systems, which account for over 30% of the energy consumed in a typical office building is however hampered due to the lack of comprehensive fine-grained occupancy information. Given that comprehensive fine-grained occupancy information improves the performance of demand-driven measures, this paper presents a review of common existing systems utilized in buildings for occupancy detection. Furthermore, experimental results from the performance evaluation of chair sensors in an office building for providing fine-grained occupancy information for demand-driven control applications are presented.

Occupancy data: unravelling the mystery

Abstract: Objective: The main purpose of this study was to clarify the method used to calculate bed occupancy rates. Design: Qualitative, using semi structured face to face interviews, telephone interviews and email correspondence with internal and external stakeholders, as well as analysis of key documents. Setting: A tertiary hospital in Queensland, Australia. Participants: Nursing and administrative staff from 34 clinical areas, nurse managers and finance officers. Main outcome measure: Identification of the method used to calculate bed occupancy. Results: A number of issues potentially impact on the accuracy of occupancy data including timeliness of data entry, knowledge about what should be entered and skill deficits. There was also considerable confusion and misinformation about how occupancy data is calculated, used and reported. Conclusion: Occupancy data integrity may be compromised by timeliness and accuracy of data entry and by methods used for calculation. Until these problems are resolved, occupancy remains a woolly measure on which to estimate nursing resources.

Improving occupancy presence prediction via multi-label classification

Abstract: Heating and cooling of commercial buildings accounts for a large proportion of worldwide energy consumption. There exists an opportunity to reduce energy waste by improving the scheduling of heating, ventilation, and air conditioning (HVAC) based on occupancy. However, to enable this potential, we require more accurate methods for predicting occupancy to deliver the required level of comfort when rooms are occupied. This paper examines the novel use of multi-label classification (MLC) for predicting occupancy of rooms based on data from motion sensors. Stating the occupancy prediction problem as an MLC problem enables the use of existing MLC algorithms and provides a solid foundation for evaluating the performance of the predictive models. Our implemented algorithms are benchmarked against an existing occupancy prediction technique (PreHeat) on a dataset from two commercial buildings. The results show that PreHeat and Support Vector Machine (SVM) outperforms other algorithms for rooms with high occupancy frequency. Other machine learning algorithms outperform PreHeat and SVM for rooms with low occupancy frequency. In total, SVM provides a more robust performance than other algorithms with a significantly higher count of highest prediction accuracy for observed scenarios. Our experimental results also highlight that prediction performance for commercial buildings depends more on occupancy frequency than occupancy rate, and the occupancy state before the prediction horizon. By presenting more accurate algorithms for occupancy prediction, we hope to foster the development of more energy-efficient HVAC scheduling systems to reduce overall energy consumption.

Relating Yellow Rail (Coturnicops noveboracensis) Occupancy to Habitat and Landscape Features in the Context of Fire

Abstract: . The Yellow Rail (Coturnicops noveboracensis) is a focal species of concern associated with shallowly flooded emergent wetlands, most commonly sedge (Carex spp.) meadows. Their populations are believed to be limited by loss or degradation of wetland habitat due to drainage, altered hydrology, and fire suppression, factors that have often resulted in encroachment of shrubs into sedge meadows and change in vegetative cover. Nocturnal call-playback surveys for Yellow Rails were conducted over 3 years at Seney National Wildlife Refuge in the Upper Peninsula of Michigan. Effects of habitat structure and landscape variables on the probability of use by Yellow Rails were assessed at two scales, representing a range of home range sizes, using generalized linear mixed models. At the 163-m (8-ha) scale, year with quadratic models of maximum and mean water depths best explained the data. At the 300-m (28-ha) scale, the best model contained year and time since last fire (≤ 1, 2–5, and > 10 years). The probab...

Couch potatoes do better: Delayed dispersal and territory size affect the duration of territory occupancy in a monogamous mammal.

Abstract: In territorial, socially monogamous species, the establishment and defense of a territory are an important strategy to maximize individual fitness, but the factors responsible for the duration of territory occupancy are rarely studied, especially in long-lived mammals. A long-term monitoring program in southeast Norway spanning over 18 years allowed us to follow the individual life histories of Eurasian beavers (Castor fiber) from adolescence in their natal family group to dispersal and territory establishment until the end of territory occupancy. We investigated whether territory size, resource availability, population density, and dispersal age could explain the duration of territory occupancy, which ranged from 1 to 11 years. The duration of territory occupancy was positively related to dispersal age, suggesting that individuals that delayed dispersal had a competitive advantage due to a larger body mass. This is in support with the maturation hypothesis, which states that an animal should await its physical and behavioral maturation before the acquisition of a territory. Further, we found that individuals that established in medium-sized territories occupied them longer as compared to individuals in small or large territories. This suggests that large territories are more costly to defend due to an increased patrolling effort, and small territories might not have sufficient resources. The lifetime reproductive success ranged from zero to six kits and generally increased with an increasing duration of territory occupancy. Our findings show the importance of holding a territory and demonstrate that dispersal decisions and territory selection have important consequences for the fitness of an individual.