6,129 research outputs found
Progress on Intelligent Guidance and Control for Wind Shear Encounter
Low altitude wind shear poses a serious threat to air safety. Avoiding severe wind shear challenges the ability of flight crews, as it involves assessing risk from uncertain evidence. A computerized intelligent cockpit aid can increase flight crew awareness of wind shear, improving avoidance decisions. The primary functions of a cockpit advisory expert system for wind shear avoidance are discussed. Also introduced are computational techniques being implemented to enable these primary functions
The effect of feedback and information on children's pedometer step counts at school
This study examined whether feedback or feedback plus physical activity information could increase the number of pedometer steps taken during 1 school week. One hundred seventy-seven students (mean age 9.124 ± 1.11 years) in three elementary schools participated. Schools were randomly assigned to control (CON), feedback (FB), or feedback plus information (FB+I) groups. Children wore pedometers during school time for 5 consecutive weekdays. The total steps of the groups were recorded at the end of each school day, with students in the FB and FB+I groups free to view their step counts. In addition, the FB+I group received information and ideas about how they could increase their daily steps. The CON group received no step-count feedback or information. Students in the FB+I group achieved significantly more steps per minute (17.17 ± 4.87) than those in the FB (13.77 ± 4.06, p = 0.003) and CON (12.41 ± 3.12, p = 0.0001) groups. Information, as well as step-count feedback, increased elementary students’ school-based physical activity (number of steps) in the short term. A longer intervention period is necessary to assess the sustained impact of this type of approach
Learning from the experts: exploring playground experience and activities using a write and draw technique.
BACKGROUND: Qualitative research into the effect of school recess on children's physical activity is currently limited. This study used a write and draw technique to explore children's perceptions of physical activity opportunities during recess. METHODS: 299 children age 7-11 years from 3 primary schools were enlisted. Children were grouped into Years 3 & 4 and Years 5 & 6 and completed a write and draw task focusing on likes and dislikes. Pen profiles were used to analyze the data. RESULTS: Results indicated 'likes' focused on play, positive social interaction, and games across both age groups but showed an increasing dominance of games with an appreciation for being outdoors with age. 'Dislikes' focused on dysfunctional interactions linked with bullying, membership, equipment, and conflict for playground space. Football was a dominant feature across both age groups and 'likes/dislikes' that caused conflict and dominated the physically active games undertaken. CONCLUSION: Recess was important for the development of conflict management and social skills and contributed to physical activity engagement. The findings contradict suggestions that time spent in recess should be reduced because of behavioral issues
New concept in brazing metallic honeycomb panels
Aluminum oxide coating provides surface which will not be wetted by brazing alloy and which stops metallic diffusion welding of tooling materials to part being produced. This method eliminates loss of tooling materials and parts from braze wetting and allows fall-apart disassembly of tooling after brazing
Systematic innovation and the underlying principles behind TRIZ and TOC
Innovative developments in the design of product and manufacturing systems are often marked by simplicity, at least in retrospect, that has previously been shrouded by restrictive mental models or limited knowledge transfer. These innovative developments are often associated with the breaking of long established trade-off compromises, as in the paradigm shift associated with JIT & TQM, or the resolution of design contradictions, as in the case of the dual cyclone vacuum cleaner. The rate of change in technology and the commercial environment suggests the opportunity for innovative developments is accelerating, but what systematic support is there to guide this innovation process. This paper brings together two parallel, but independent theories on inventive problem solving; one in mechanical engineering, namely the Russian Theory of Inventive Problem Solving (TRIZ) and the other originating in manufacturing management as the Theory of Constraints (TOC). The term systematic innovation is used to describe the use of common underlying principles within these two approaches. The paper focuses on the significance of trade-off contradictions to innovation in these two fields and explores their relationship with manufacturing strategy development
Bessel beam propagation: Energy localization and velocity
The propagation of a Bessel beam (or Bessel-X wave) is analyzed on the basis
of a vectorial treatment. The electric and magnetic fields are obtained by
considering a realistic situation able to generate that kind of scalar field.
Specifically, we analyze the field due to a ring-shaped aperture over a
metallic screen on which a linearly polarized plane wave impinges. On this
basis, and in the far field approximation, we can obtain information about the
propagation of energy flux and the velocity of the energy.Comment: 6 pages, 4 figure
An expert system for wind shear avoidance
A study of intelligent guidance and control concepts for protecting against the adverse effects of wind shear during aircraft takeoffs and landings is being conducted, with current emphasis on developing an expert system for wind shear avoidance. Principal objectives are to develop methods for assessing the likelihood of wind shear encounter (based on real-time information in the cockpit), for deciding what flight path to pursue (e.g., takeoff abort, landing go-around, or normal climbout or glide slope), and for using the aircraft's full potential for combating wind shear. This study requires the definition of both deterministic and statistical techniques for fusing internal and external information , for making go/no-go decisions, and for generating commands to the manually controlled flight. The program has begun with the development of the WindShear Safety Advisor, an expert system for pilot aiding that is based on the FAA Windshear Training Aid; a two-volume manual that presents an overview , pilot guide, training program, and substantiating data provides guidelines for this initial development. The WindShear Safety Advisor expert system currently contains over 200 rules and is coded in the LISP programming language
Associations between selected demographic, biological, school environmental and physical education based correlates, and adolescent physical activity
The study investigated associations between selected physical activity correlates among 299 adolescents (90 boys, age 12-14 years) from 3 English schools. Physical activity was assessed by self-report and accelerometry. Correlates represented biological, predisposing, and demographic factors as described in the Youth Physical Activity Promotion Model. Boys engaged in more self-reported (p < .01) and accelerometer assessed physical activity than girls (p = .02). Positive associations between sex (male), BMI, Perceived PE Ability, Perceived PE Worth, number of enrolled students, and physical activity outcomes were evident (p < .05). Schoolbased physical activity promotion should emphasize sex-specific enhancement of students' perceived PE competence and enjoyment
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North Campus Open Space Restoration Project As-Built Grading and Hydrology Report
This report describes the as-built geomorphology and hydrology of the North Campus Open Space (NCOS) restoration project at the completion of the grading phase of the project. Topics covered include: a comparison of the predicted and as-built grading elevations, as-built cross-sections and thalwegs of the two main channels, and a comparison of the hydrology of the project site before and after the completion of the grading phase. A selection of photos of the project site taken before and after the completion of grading are provided at the end of the report. Ongoing project work not covered in this report includes: trail and bridge construction, planting and site maintenance, and the planned construction of a visitor interpretative plaza and maintenance equipment shed
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North Campus Open Space Restoration Project Annual Monitoring Report: Year 2 (2019)
Born out of a vision shared by the local community, students, faculty, researchers and state and federal agencies, the North Campus Open Space (NCOS) restoration project is recreating more than 40 acres of estuarine and palustrine wetlands that historically comprised the upper portion of Devereux Slough that was filled in the mid-1960s to create the Ocean Meadows golf course. Led by the UC Santa Barbara Cheadle Center for Biodiversity and Ecological Restoration (CCBER) in collaboration with other UCSB departments, faculty, student and local community groups, contractors and government agencies, the project is also restoring more than 60 acres of upland habitats that include native grassland, coastal sage scrub, riparian, oak chaparral woodland, vernal pools and patches of annual wildflowers in clay and sandy soils. In addition to wetland and upland habitat restoration, the goals of the NCOS project include flood reduction, support for threatened and endangered species, public access and the provision of educational opportunities. Ancillary benefits of the project include carbon sequestration, preservation of local genotypes, and protection of adjacent ecological values and infrastructure through a design that integrates sea level rise considerations.Currently in its third year of implementation, the main planting phase of the project is approximately 90% complete, and the focus is now turning towards maintenance, continued monitoring, new research projects, and supplemental planting to add diversity, including special status species such as the Ventura marsh milk-vetch (Astragalus pycnostachys var. lanosissimus). This report describes the methods and results of monitoring for the first two years of the project, from vegetation and wildlife to wetland geomorphology, hydrology and water quality, carbon sequestration studies, community use and a detailed record of restoration efforts by type of worker, task and site location. This work documents the progress of the project and supports longer-term research and monitoring programs. Results from the second year of monitoring show substantial progress towards the project’s restoration goals, with many being met or exceeded
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