882 research outputs found
ActivityAware: Wearable System for Real-Time Physical Activity Monitoring among the Elderly
Physical activity helps reduce the risk of cardiovascular disease, hypertension and obesity. The ability to monitor a person’s daily activity level can inform self-management of physical activity and related interventions. For older adults with obesity, the importance of regular, physical activity is critical to reduce the risk of long-term disability. In this work, we present ActivityAware, an application on the Amulet wrist-worn device that monitors the daily activity levels (low, moderate and vigorous) of older adults in real-time. The app continuously collects acceleration data on the Amulet, classifies the current activity level, updates the day’s accumulated time spent at that activity level, displays the results on the screen and logs summary data for later analysis. The app implements an activity-level detection model we developed using a Linear Support Vector Machine (SVM). We trained our model using data from a user study, where subjects performed common physical activities (sit, stand, lay down, walk and run). We obtained accuracies up to 99.2% and 98.5% with 10-fold cross validation and leave-one-subject-out (LOSO) cross-validation respectively. We ran a week-long field study to evaluate the utility, usability and battery life of the ActivityAware system where 5 older adults wore the Amulet as it monitored their activity level. The utility evaluation showed that the app was somewhat useful in achieving the daily physical activity goal. The usability feedback showed that the ActivityAware system has the potential to be used by people for monitoring their activity levels. Our energy-efficiency evaluation revealed a battery life of at least 1 week before needing to recharge. The results are promising, indicating that the app may be used for activity-level monitoring by individuals or researchers for epidemiological studies, and eventually for the development of interventions that could improve the health of older adults
StressAware: App for Continuously Measuring and Monitoring Stress Levels in Real Time on the Amulet Wearable Device
Stress is the root cause of many diseases. Being able to monitor when and why a person is stressed could inform personal stress management as well as interventions when necessary. In this thesis, I present StressAware, an application on the Amulet wearable platform to measure the stress levels of individuals continuously and in real time. The app implements a stress detection model, continuously streams heart rate data from a commercial heart-rate monitor such as a Zephyr and Polar H7, classifies the stress level of an individual, logs the stress level and then displays it as a graph on the screen. I developed a stress detection model using a Linear Support Vector Machine. I trained my classifiers using data from 3 sources: PhysioNet, a public database with various physiological data, a field study, where subjects went about their normal daily activities and a lab study in a controlled environment, where subjects were exposed to various stressors. I used 73 data segments of stress data obtained from PhysioNet, 120 data segments from the field study, and 14 data segments from the lab study. I extracted 14 heart rate and heart rate variability features. With 10-fold cross validation for Radial Basis Function (RBF) SVM, I obtained an accuracy of 94.5% for the PhysioNet dataset and 100% for the field study dataset. And for the lab study, I obtained an accuracy of 64.29% with leave-one-out cross-validation. Testing the StressAware app revealed a projected battery life of up to 12 days before needing to recharge. Also, the usability feedback from subjects showed that the Amulet and Zephyr have a potential to be used by people for monitoring their stress levels. The results are promising, indicating that the app may be used for stress detection, and eventually for the development of stress-related intervention that could improve the health of individuals
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Domestic Rainwater Harvesting in a Water-Stressed Community and Variation in Rainwater Quality from Source to Storage
The quality of rainwater, which is the main source of domestic water in Dzodze, a community in the Volta Region of Ghana, was unknown. Therefore, the possible utilization of contaminated domestic water and occurrence of health hazards could not be underestimated due to prevailing poor hygiene and a great lack of standard maintenance and treatment systems in the community. In this study, we assessed the quality of rainwater in the Dzodze Community community and how it varies along the DRWH chain from free-fall to storage. Rain samples were collected at three points along the domestic rainwater harvesting (DRWH) chain. Specifically, the three points from were free-fall, roof-catchmentroof catchment, and storage tank, and the two systems were "described as poorly-maintained" and "well-maintained" systems. The physico-chemical and bacteriological patterns of rainwater samples were analyzed for physico-chemical and bacteriological parameters and results were compared with World Health Organization (and Ghana Standards Board guideline values. The harvested rainwater was found to be of good physico-chemical quality, but not bacteriological, quality but not bacteriological, calling for treatment before utilization. Also, irrespective of the type of DRWH system (poorly-maintained or well-maintained), there were substantial changes in rainwater quality upon interaction with roof catchment, with an increase noticed in all parameters
Technological Innovations and Emergency Medical Services (EMS) in the Ashanti Region: An Evaluation of the National Ambulance Service’s Support to Referral Centres
The practice of Emergency Medical Services (EMS) encompasses the pre-hospital and in-hospital triage, resuscitation, initial assessment and management of undifferentiated urgent and emergency cases until discharge or transfer to the care of another physician or health care professional. This involves the development and deployment of pre-hospital and in-hospital emergency medical systems for rescue processes. Thus, the goal of effective EMS is to provide emergency medical care to all who need it. However, many factors determine the quality of EMS, and that the response time is an important EMS industry benchmark. The study assesses the level of technological innovations as a means of providing quality pre-hospital care to patients in times of emergencies and the acceptance of such practices by Komfo Anokye Teaching Hospital (KATH) – a referral centre. All the 16 National Ambulance Service (NAS) centres in the Ashanti Region in Ghana were considered for the study, with only 93 personnel manning these stations and hence the difficulty for them to attend to concurrent cases of emergencies. Questionnaires were administered on the perceptions and opinions of patients/relatives, doctors and nurses as well as staff of the 16 ambulance service centres about EMS delivery. Systematic random sampling was used to select patients/relatives and ambulance service staff whilst convenience sampling was used to select individuals from the rest of the categories. The use of fixed telephone lines and mobile phones were the primary tools for communication. For quality evidence-based EMS practices, NAS lacked the integration of GIS, GPS and GSM technologies including mobile tablet PCs and software solution to properly discharge their duties. Keywords: Emergency Medical Services (EMS), referral center, pre-hospital and in-hospital, National Ambulance Service (NAS), innovative technologies, time, ‘golden hour’, Mobile Data Terminal (MDT
Rock Characteristics and Ball Mill Energy Requirements at Goldfields Ghana Limited, Tarkwa Gold Mine (TGM)
Mineral processing plants often experience changes in throughput; blending patterns, and rock properties. These changes can have great impact on milling operations. As mining progresses, new deposits are discovered, which may have different characteristics from the designed plant parameters, a situation requiring re-assessment of the plant operating parameters. Goldfields Ghana Limited, Tarkwa Gold Mine (TGM), processes ores which occur in conglomerate reefs. The competence of the ore was observed to increase with increasing mining depth. Other rock properties such as porosity, micro-cracks and gold dissolution were also observed to change with depth. It therefore became necessary to conduct a study to ascertain the effect of changes in rock characteristics on the performance of the existing ball mill. The study characterized the mineralogy and rock characteristics of the ores being mined from three pits and the results were compared with design parameters. The parameters examined had deviated from the design; Work Index (WI) for example was lower than design and required simulation and adjustment. Samples taken at the same depth from each of the pits showed that Akontasi Pit has the most competent ores, followed by Kottraverchi Pit and then Teberebie Pit. Furthermore, throughput was the most sensitive variable and easiest to manipulate to achieve the energy draw required. Simulations showed that a plant throughput of about 1665 t/hr, instead of the current value of 1500 t/hr would be most suitable as an energy draw solution.Keywords: Work index, Power draw, Computer simulatio
Growth and yield response of carrot (Daucus carota l.) to different rates of soil amendments and spacing
A 5 x 2 factorial field experiment in a randomised complete block design with four replications was conducted at the College of Agriculture Education, University of Education, Winneba, Mampong Campus to investigate the growth and yield responses of carrot to different rates of soil amendments and spacing. The five rates of soil amendments were: (i) 10 t/ha chicken manure (ii) 15 t/ha chicken manure (iii) 20 t/ha chicken manure (iv) 300 kg/ha NPK (15-15-15) and (v) Control (no soil amendment). The two spacings were: (i) 30 cm x 5 cm and (ii) 20 cm x 5 cm. The application of 15 t/ha and 20 t/ha decomposed chicken manure improved vegetative growth, increased root yield and gave more income. More plants were however, infected by Sclerotium rolfsii by the application of the 20t/ha chicken manure. Soil amendment rates did not suppress nematode populations but the highest root galling index was recorded on the control plants. The wider spacing of 30cm x 5cm promoted vegetative growth and increased root length of carrot but planting at closer spacing of 20cm x 5cm resulted in higher total and marketable yields and also increased income and profit
Superior Communication of Positive Emotions Through Nonverbal Vocalisations Compared to Speech Prosody
Granular Flows in a Rotating Drum: the Scaling Law between Velocity and Thickness of the Flow
The flow of dry granular material in a half-filled rotating drum is studied.
The thickness of the flowing zone is measured for several rotation speeds, drum
sizes and beads sizes (size ratio between drum and beads ranging from 47 to
7400). Varying the rotation speed, a scaling law linking mean velocity vs
thickness of the flow, , is deduced for each couple (beads, drum).
The obtained exponent is not always equal to 1, value previously reported
in a drum, but varies with the geometry of the system. For small size ratios,
exponents higher than 1 are obtained due to a saturation of the flowing zone
thickness. The exponent of the power law decreases with the size ratio, leading
to exponents lower than 1 for high size ratios. These exponents imply that the
velocity gradient of a dry granular flow in a rotating drum is not constant.
More fundamentally, these results show that the flow of a granular material in
a rotating drum is very sensible to the geometry, and that the deduction of the
``rheology'' of a granular medium flowing in such a geometry is not obvious
Spatial distribution of nematodes at organic and conventional crop fields in Cape Coast, Ghana
Globally, plant-parasitic nematodes cause large reductions in crop yields and quality. The conditions prevalent in organic crop production fields can favour or inhibit nematode build-up. An overview of the spatial distribution of nematodes can help the design of targeted, site-specific management strategies. This paper assessed and compared the spatial distribution of nematode population in an organic crop field and a conventional crop field using Inverse Distance Weighted (IDW) and ordinary Kriging spatial interpolation techniques. The results show that nematode population is higher on the organic field compared to the conventional crop field. Spatial distribution of nematode population showed a north-south gradient in the organic field but small patches of large population in the conventional field. The two interpolation methods did not show substantial differences in mapping the spatial distribution of the nematode population. It is concluded that nematode control strategies employed on the organic field might be less effective than expected. Both inverse distance weighted and ordinary kriging can be used to map the spatial distribution of nematodes under similar conditions and in a non-complex terrain
Detection of viable Mycobacterium ulcerans in clinical samples by a novel combined 16S rRNA reverse transcriptase/IS2404 real-time qPCR assay.
Detection of Viable <em>Mycobacterium ulcerans</em> in Clinical Samples by a Novel Combined 16S rRNA Reverse Transcriptase/IS<em>2404</em> Real-Time qPCR Assa
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