44 research outputs found
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CONVERGING REDUNDANT SENSOR NETWORK INFORMATION FOR IMPROVED BUILDING CONTROL
Knowing how many people occupy a building, and where they are located, is a key component of building energy management and security. Commercial, industrial and residential buildings often incorporate systems used to determine occupancy, however, current sensor technology and control algorithms limit the effectiveness of both energy management and security systems. This topical report describes results from the first phase of a project to design, implement, validate, and prototype new technologies to monitor occupancy, control indoor environment services, and promote security in buildings. Phase I of the project focused on instrumentation and data collection. In this project phase a new occupancy detection system was developed, commissioned and installed in a sample of private offices and open-plan office workstations. Data acquisition systems were developed and deployed to collect data on space occupancy profiles. Analysis tools based on Bayesian probability theory were applied to the occupancy data generated by the sensor network. The inference of primary importance is a probability distribution over the number of occupants and their locations in a building, given past and present sensor measurements. Inferences were computed for occupancy and its temporal persistence in individual offices as well as the persistence of sensor status. The raw sensor data were also used to calibrate the sensor belief network, including the occupancy transition matrix used in the Markov model, sensor sensitivity, and sensor failure models. This study shows that the belief network framework can be applied to the analysis of data streams from sensor networks, offering significant benefits to building operation compared to current practice
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Converging Redundant Sensor Network Information for Improved Building Control
This project investigated the development and application of sensor networks to enhance building energy management and security. Commercial, industrial and residential buildings often incorporate systems used to determine occupancy, but current sensor technology and control algorithms limit the effectiveness of these systems. For example, most of these systems rely on single monitoring points to detect occupancy, when more than one monitoring point could improve system performance. Phase I of the project focused on instrumentation and data collection. During the initial project phase, a new occupancy detection system was developed, commissioned and installed in a sample of private offices and open-plan office workstations. Data acquisition systems were developed and deployed to collect data on space occupancy profiles. Phase II of the project demonstrated that a network of several sensors provides a more accurate measure of occupancy than is possible using systems based on single monitoring points. This phase also established that analysis algorithms could be applied to the sensor network data stream to improve the accuracy of system performance in energy management and security applications. In Phase III of the project, the sensor network from Phase I was complemented by a control strategy developed based on the results from the first two project phases: this controller was implemented in a small sample of work areas, and applied to lighting control. Two additional technologies were developed in the course of completing the project. A prototype web-based display that portrays the current status of each detector in a sensor network monitoring building occupancy was designed and implemented. A new capability that enables occupancy sensors in a sensor network to dynamically set the 'time delay' interval based on ongoing occupant behavior in the space was also designed and implemented
Testing the Effectiveness of the “Smelly” Elephant Repellent in Controlled Experiments in Semi-Captive Asian and African Savanna Elephants
Simple Summary:
Mitigating and reducing the impacts of elephant crop-raiding has become a major focus of conservation intervention. By observing the behaviour amongst two groups of semi-captive African and Asian elephants in Zambia and Thailand, we found that a novel olfactory crop-raiding mitigation method called the “smelly elephant repellent” elicited clear reactions from the elephants. However, unlike trials with wild elephants, the repellent did not prevent the elephants from entering areas or eating food protected by the solution. We found that elephant personality played a role in responses towards the repellent, as the individuals that entered the experimental plots were bolder and more curious individuals. Although captive environments provide controlled settings for experimental testing, the ecological validity of testing human–elephant conflict mitigation methods with captive wildlife should be strongly considered. Understanding animal behaviour is essential for improving human–elephant coexistence and for designing deterrence mechanisms, and the smelly elephant repellent may be a useful mitigation method when used in combination with other methods.
Abstract:
Crop-raiding by elephants is one of the most prevalent forms of human–elephant conflict and is increasing with the spread of agriculture into wildlife range areas. As the magnitude of conflicts between people and elephants increases across Africa and Asia, mitigating and reducing the impacts of elephant crop-raiding has become a major focus of conservation intervention. In this study, we tested the responses of semi-captive elephants to the “smelly” elephant repellent, a novel olfactory crop-raiding mitigation method. At two trial sites, in Zambia and Thailand, African elephants (Loxodonta africana) and Asian elephants (Elephas maximus) were exposed to the repellent, in order to test whether or not they entered an area protected by the repellent and whether they ate the food provided. The repellent elicited clear reactions from both study groups of elephants compared to control conditions. Generalised linear models revealed that the elephants were more alert, sniffed more, and vocalised more when they encountered the repellent. Although the repellent triggered a response, it did not prevent elephants from entering plots protected by the repellent or from eating crops, unlike in trials conducted with wild elephants. Personality played a role in responses towards the repellent, as the elephants that entered the experimental plots were bolder and more curious individuals. We conclude that, although captive environments provide controlled settings for experimental testing, the ecological validity of testing human–elephant conflict mitigation methods with captive wildlife should be strongly considered. This study also shows that understanding animal behaviour is essential for improving human–elephant coexistence and for designing deterrence mechanisms. Appreciating personality traits in elephants, especially amongst “problem” elephants who have a greater propensity to crop raid, could lead to the design of new mitigation methods designed to target these individuals
AB-10-017: Combined effects of noise and temperature on human comfort and performance (1128-RP)
This paper summarizes results from an experiment designed to investigate the combined effects of noise and temperature on human thermal comfort and task performance. Thirty subjects (16 females, 14 males) were exposed to all combinations of five thermal conditions (PMV +1 [79.6°F:26.4°C], PMV +0.5 [75.8°F:24.3°C], PMV 0 [72.1°F:22.3°C], PMV -0.5 [68.3°F:20.2°C], and PMV -1 [64.6°F:18.1°C]), three RC noise levels (RC-30, RC-40, and RC-50), and two sound qualities (neutral and rumbly): all sounds mimicked noise from building ventilation systems. After a one-hour adaptation period at each condition, subjects rated their thermal comfort using the ASHRAE Thermal Comfort Scale and the Tenant Survey Questionnaire, and then completed typing and number-checking tasks. There were no statistically significant effects of thermal condition, RC level, or sound quality on performance of the typing or number-checking tasks. Statistical analyses showed that thermal comfort was affected by RC noise level, while ratings of building or office noise were not affected by the ambient temperature. There were also differences in the way males and females experienced the thermal and acoustical environments. Females rated lower temperatures colder than males, and higher temperatures more pleasant than males: thermal comfort composite ratings from males and females converged at about 72°F (22°C)
Assessment of Photoluminescent Material during Office Occupant Evacuation
this report in order to adequately specify the experiment procedure. In no case does such identification imply recommendations or endorsement by the National Research Council, nor does it imply that the product or material identified is the best available for the purpose. 13 Figure 4: Data Acquisition in Stairwells The picture on the left shows the configuration used in the stairwells (the stairwell depicted was not one measured in this study). The illuminance meters are mounted on a pillar such that the plane of the detectors is 1 m above the stair tread. The operator manually directs the software and data acquisition hardware mounted on the laptop computer to poll the illuminance meter, and store the measured values on the computer hard disk. Once the polling operation has been completed, the operator moves the apparatus to the next measurement location, and repeats the operation. The picture on the right shows the configuration used to collect measurements on the floors. The operator pushes the device along the centreline of the measurement path. As the calibrated wheel (circumference 1 m) turns, the data acquisition system is directed to poll the illuminance meters and store the resulting value in the computer once every 25 cm of travel. For the stairwells, a total of 12 readings were collected between each floor as follows: three readings were collected at the door landing and the mid-landing, and one each at the top, middle and last stair of each staircase. The data acquisition system software was configured so each reading was polled by the operator manually once the apparatus was correctly placed. All stairwells were windowless, so no daylight supplemented the electric lighting. On Floors 9, 10 and 11, the operator pushed the measuring system along the centreli..
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Elephants have a nose for quantity.
Animals often face situations that require making decisions based on quantity. Many species, including humans, rely on an ability to differentiate between more and less to make judgments about social relationships, territories, and food. Habitat-related choices require animals to decide between areas with greater and lesser quantities of food while also weighing relative risk of danger based on group size and predation risk. Such decisions can have a significant impact on survival for an animal and its social group. Many species have demonstrated a capacity for differentiating between two quantities of food and choosing the greater of the two, but they have done so based on information provided primarily in the visual domain. Using an object-choice task, we demonstrate that elephants are able to discriminate between two distinct quantities using their olfactory sense alone. We presented the elephants with choices between two containers of sunflower seeds. The relationship between the amount of seeds within the two containers was represented by 11 different ratios. Overall, the elephants chose the larger quantity of food by smelling for it. The elephants' performance was better when the relative difference between the quantities increased and worse when the ratio between the quantities of food increased, but was not affected by the overall quantity of food presented. These results are consistent with the performance of animals tested in the visual domain. This work has implications for the design of future, cross-phylogenetic cognitive comparisons that ought to account for differences in how animals sense their world
Context
Illuminating engineers, lighting designers and others have long debated the importance of providing an artificial light source that mimics the characteristics of natural light. Several products are available that purport to provide more natural light, of which retrofit plastic filters are one. Product testimonials praising these products abound, but there is little empirical data concerning their effects on the visual environment. This paper reports two experiments concerning this issue, the first being a test of the hypothesis that selected retrofit magenta filters improve skin appearance in comparison to other common lighting sources or a placebo condition. The second experiment tested the hypothesis that selected retrofit magenta filters improve short-term visual performance, compared to other common lighting sources or a placebo condition. The results show that the selected filters improved skin appearance relative to unfiltered fluorescent lamps. There were no differences between preferences for skin appearance under comparable magenta filters from two different manufacturers. In general, light sources relatively richer in red than green were preferred. There were no effects of light source spectral composition on short-term visual performance