1,354 research outputs found
Increasing transmission efficiency with advanced signal processing
Optical CDMA is an advanced and flexible communication technology with a potential to offer very energy efficient and highly scalable networking. In addition it can also deliver increased physical layer privacy and on-demand bandwidth sharing management. We have developed, extensively investigated, and experimentally demonstrated highly scalable approach to incoherent OCDMA which can very efficiently increase the number of simultaneous users. In addition, the introduction of an advanced photonic signal processing results in an overall system power budget improvement by nearly 3dB. Error-free operation with the BER less than 10-12 was achieved. We have also shown that with demonstrated approach we can dramatically improve number of simultaneous network users (up to ten times) while keeping the related hardware count unchanged. By comparing this results to DWDM concept, this substantial increase in number of simultaneous users did not require to add any additional wavelength laser sources and was achieved by employing just three communication wavelengths
Wireless sensor network for cattle monitoring system
This paper describes a cost effective Wireless Sensor Network (WSN) technology for monitoring the health of dairy cows. By monitoring and understanding the cow individual and herd behaviour, farmers can potentially identify the onset of illness, lameness or other undesirable health conditions. However, the WSN implementation needs to cope with various technical challenges before it can be suitably and routinely applied in cow management. This paper discusses results concerning data transportation (i.e. mobility) from the cow mounted sensory devices
Methods of Health Behavior Change
Peopleâs behavior influences health, for example, in the prevention, early detection, and treatment of disease, the management of illness, and the optimization of healthcare professionalsâ behaviors. Behaviors are part of a system of behaviors within and between people in that any one behavior is influenced by others. Methods for changing behavior may be aimed at individuals, organizations, communities, and/or populations and at changing different influences on behavior, e.g., motivation, capability, and the environment. A framework that encapsulates these influences is the Behavior Change Wheel, which links an understanding of behavior in its context with methods to change behavior. Within this framework, methods are conceptualized at three levels: policies that represent high-level societal and organizational decisions, interventions that are more direct methods to change behavior, and behavior change techniques that are the smallest components that on their own have the potential to change behavior. In order to provide intervention designers with a systematic method to select the policies, interventions, and/or techniques relevant for their context, a set of criteria can be used to help select intervention methods that are likely to be implemented and effective. One such set is the âAPEASEâ criteria: affordability, practicability, effectiveness, acceptability, safety, and equity
Statistical interaction modeling of bovine herd behaviors
While there has been interest in modeling the group behavior of herds or flocks, much of this work has focused on simulating their collective spatial motion patterns which have not accounted for individuality in the herd and instead assume a homogenized role for all members or sub-groups of the herd. Animal behavior experts have noted that domestic animals exhibit behaviors that are indicative of social hierarchy: leader/follower type behaviors are present as well as dominance and subordination, aggression and rank order, and specific social affiliations may also exist. Both wild and domestic cattle are social species, and group behaviors are likely to be influenced by the expression of specific social interactions. In this paper, Global Positioning System coordinate fixes gathered from a herd of beef cows tracked in open fields over several days at a time are utilized to learn a model that focuses on the interactions within the herd as well as its overall movement. Using these data in this way explores the validity of existing group behavior models against actual herding behaviors. Domain knowledge, location geography and human observations, are utilized to explain the causes of these deviations from this idealized behavior
The formation of ultra-compact dwarf galaxies and nucleated dwarf galaxies
Ultra compact dwarf galaxies (UCDs) have similar properties as massive
globular clusters or the nuclei of nucleated galaxies. Recent observations
suggesting a high dark matter content and a steep spatial distribution within
groups and clusters provide new clues as to their origins. We perform
high-resolution N-body / smoothed particle hydrodynamics simulations designed
to elucidate two possible formation mechanisms for these systems: the merging
of globular clusters in the centre of a dark matter halo, or the massively
stripped remnant of a nucleated galaxy. Both models produce density profiles as
well as the half light radii that can fit the observational constraints.
However, we show that the first scenario results to UCDs that are underluminous
and contain no dark matter. This is because the sinking process ejects most of
the dark matter particles from the halo centre. Stripped nuclei give a more
promising explanation, especially if the nuclei form via the sinking of gas,
funneled down inner galactic bars, since this process enhances the central dark
matter content. Even when the entire disk is tidally stripped away, the nucleus
stays intact and can remain dark matter dominated even after severe stripping.
Total galaxy disruption beyond the nuclei only occurs on certain orbits and
depends on the amount of dissipation during nuclei formation. By comparing the
total disruption of CDM subhaloes in a cluster potential we demonstrate that
this model also leads to the observed spatial distribution of UCDs which can be
tested in more detail with larger data sets.Comment: 8 pages, 8 figures, final version accepted for publication in MNRA
Measures of fidelity of delivery of, and engagement with, complex, face-to-face health behaviour change interventions: A systematic review of measure quality
PURPOSE: Understanding the effectiveness of complex, face-to-face health behaviour change interventions requires high-quality measures to assess fidelity of delivery and engagement. This systematic review aimed to (1) identify the types of measures used to monitor fidelity of delivery of, and engagement with, complex, face-to-face health behaviour change interventions and (2) describe the reporting of psychometric and implementation qualities. METHODS: Electronic databases were searched, systematic reviews and reference lists were hand-searched, and 21 experts were contacted to identify articles. Studies that quantitatively measured fidelity of delivery of, and/or engagement with, a complex, face-to-face health behaviour change intervention for adults were included. Data on interventions, measures, and psychometric and implementation qualities were extracted and synthesized using narrative analysis. RESULTS: Sixty-six studies were included: 24 measured both fidelity of delivery and engagement, 20 measured fidelity of delivery, and 22 measured engagement. Measures of fidelity of delivery included observation (n = 17; 38.6%), self-report (n = 15; 34%), quantitatively rated qualitative interviews (n = 1; 2.3%), or multiple measures (n = 11; 25%). Measures of engagement included self-report (n = 18; 39.1%), intervention records (n = 11; 24%), or multiple measures (n = 17; 37%). Fifty-one studies (77%) reported at least one psychometric or implementation quality; 49 studies (74.2%) reported at least one psychometric quality, and 17 studies (25.8%) reported at least one implementation quality. CONCLUSION: Fewer than half of the reviewed studies measured both fidelity of delivery of, and engagement with complex, face-to-face health behaviour change interventions. More studies reported psychometric qualities than implementation qualities. Interpretation of intervention outcomes from fidelity of delivery and engagement measurements may be limited due to a lack of reporting of psychometric and implementation qualities. Statement of contribution What is already known on this subject? Evidence of fidelity and engagement is needed to understand effectiveness of complex interventions Evidence of fidelity and engagement are rarely reported High-quality measures are needed to measure fidelity and engagement What does this study add? Evidence that indicators of quality of measures are reported in some studies Evidence that psychometric qualities are reported more frequently than implementation qualities A recommendation for intervention evaluations to report indicators of quality of fidelity and engagement measures
Positioning system for wireless sensor networks with location fingerprinting
Wireless sensor networks (WSN) are networks that deploy hundreds or thousands of wireless sensors in a pre-defined area that can communicate with each other to detect, for example the ambient environment. Each sensor is composed of the four basic elements: transmitting unit, processing unit, power unit and sensing unit. The main task of each sensor is to detect events, perform a restricted set of local data processing tasks and then transmit the data. This technology still in its early stage new researches are being conducted intensively in MAC protocols, network and routing layer, and adaptation into various domains applications. In this proposal, the focus is placed to investigate algorithms in mapping the location of sensor nodes. Knowing the location of the sensor node is critically important; the knowledge of the location of the sensor node that reported a detected event can reduce the time for assistants reaching to the outbreak point. This can potentially save life or can bring the outbreak event under control in shortest time. As the sensor node's physical hardware is mainly comprises of low specification and low cost componentry to facilitate mass production hence affordable to be applied intensively in monitoring zone. This has created a tough challenge in mapping the locations of sensor nodes as the hard-ware can not provide precise timing in calculating time of flight of a packet which is an important parameter in estimating distance between transmitting node and receiving node. In general the sensor node is only equipped with a single antenna which has also rule out the possibility of using techniques rely on angle of arrival packet. Therefore, the research is limited to use the received signal strength as the main source in estimating the travelling distance for the received packet. This paper investigates positioning algorithms that based on received signal strength i.e., location fingerprinting. In positioning systems, location fingerprinting is also referred as pattern matching of radio signature. The advantages of using RF fingerprinting are it does not require any hardware modifications to the sensor node and in comparison to other algorithms it is immune environmental influences that caused signal attenuation such as multipath, fading, reflection, non line of sight, and etc. This paper focuses on challenges that relate specifically to the location mapping of wireless sensor node including radio propagation of low specification WSN hardware, accuracy, operational range and impact of environmental factors. The optimized positioning system for WSN is documented, and results gained from experiment based on IEEE 802.15.4 WSN platform is provided
Developing quality fidelity and engagement measures for complex health interventions
Objectives: To understand whether interventions are effective, we need to know whether the interventions are delivered as planned (with fidelity) and engaged with. To measure fidelity and engagement effectively, highâquality measures are needed. We outline a fiveâstep method which can be used to develop quality measures of fidelity and engagement for complex health interventions. We provide examples from a fidelity study conducted within an evaluation of an intervention aimed to increase independence in dementia. //
Methods: We propose five steps that can be systematically used to develop fidelity checklists for researchers, providers, and participants to measure fidelity and engagement. These steps include the following: (1) reviewing previous measures, (2) analysing intervention components and developing a framework outlining the content of the intervention, (3) developing fidelity checklists and coding guidelines, (4) obtaining feedback about the content and wording of checklists and guidelines, and (5) piloting and refining checklists and coding guidelines to assess and improve reliability. //
Results: Three fidelity checklists that can be used reliably were developed to measure fidelity of and engagement with, the Promoting Independence in Dementia (PRIDE) intervention. As these measures were designed to be used by researchers, providers, and participants, we developed two versions of the checklists: one for participants and one for researchers and providers. //
Conclusions: The five steps that we propose can be used to develop psychometrically robust and implementable measures of fidelity and engagement for complex health interventions that can be used by different target audiences. By considering quality when developing measures, we can be more confident in the interpretation of intervention outcomes drawn from fidelity and engagement studies
A study of the perceived risks, benefits and barriers to the use of SDD in adult critical care units (the SuDDICU study)
Peer reviewedPublisher PD
Implementation of a herd management system with wireless sensor networks
This paper investigates an adaptation of Wireless Sensor Networks (WSNs) to cattle monitoring applications. The proposed solution facilitates the requirement for continuously assessing the condition of individual animals, aggregating and reporting this data to the farm manager. There are several existing approaches to achieving animal monitoring, ranging from using a store and forward mechanism to employing GSM-based techniques; these approaches only provide sporadic information and introduce a considerable cost in staffing and physical hardware. The core of this study is to overcome the aforementioned drawbacks by using alternative cheap, low power consumption sensor nodes capable of providing real-time communication at a reasonable hardware cost. In this paper, both the hardware and software has been designed to provide a solution which can obtain real-time data from dairy cattle whilst conforming to the limitations associated with WSNs implementations
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