1,205 research outputs found
Analysis of Skylab 2 S193 scatterometer data
SKYLAB II S193 Scatterometer data for the passes of June 5, 1973, over the Gulf of Mexico and June 6, 1973, over Pacific Hurricane AVA were analyzed. The S193 scatterometer measured the radar cross section of the ocean at 13.9 GHz (Ku-band) as a function of incidence angle. The fields-of-view of the scatterometer were known. In the absence of a large body of Ku-band ocean radar data, the results of the NRL experiments at X-band (8.9 GHz) were used for comparison. The S193 data of June 5, 1973, when a practically uniform wind field was present, show reasonable agreement with the NRL empirical and theoretical models
Spontaneous structure formation in a network of chaotic units with variable connection strengths
As a model of temporally evolving networks, we consider a globally coupled
logistic map with variable connection weights. The model exhibits
self-organization of network structure, reflected by the collective behavior of
units. Structural order emerges even without any inter-unit synchronization of
dynamics. Within this structure, units spontaneously separate into two groups
whose distinguishing feature is that the first group possesses many
outwardly-directed connections to the second group, while the second group
possesses only few outwardly-directed connections to the first. The relevance
of the results to structure formation in neural networks is briefly discussed.Comment: 4 pages, 3 figures, REVTe
Computers and Learning
The important questions for instructors to address concern what skills the student is to learn and how the student is to be motivated to acquire those skills. Questions about simulations, graphics tools, and the like are unimportant until the first two questions have been answered adequately. We discuss the role of explanation by students and describe a mechanism for motivating students to learn
'Sing Every Day': An evaluation of a VOCES8 Foundation school-based singing project in Hackney, London 2019
The paper reports on a research evaluation of a six-month specialist singing project âSing Every Dayâ that was undertaken with young disadvantaged inner-city 6yo children in the London Borough of Hackney. A team of professional singers from the London-based VOCES8 Foundation visited two classes in each of two Primary schools to provide focused mentoring to generalist (non-music specialist) class teachers. Children from two identically aged classes in a neighbouring school acted as controls. The mentoring embraced a specially designed programme of singing and vocal activities across two school terms. This was undertaken in each classroom with the staff and their Year 1 children numbering N=121 in total. An independent evaluation of the impact of the project included both musical and other-than-musical measures of childrenâs development. In particular, in addition to an assessment of participant childrenâs singing behaviours at the start and at end of the project, other assessments included measures of possible changes in childrenâs reading development and in aspects of Executive Functions. Overall, the implications from the data are that the mentored classroom-based singing activities resulted in significant improvements in childrenâs singing, as well as positive changes in reading and aspects of Executive Function related to inhibition and phonological working memory â the latter being closely correlated to changes in the same childrenâs reading scores. Although there is previous research literature reporting positive links separately between music, singing, reading and aspects of Executive Functions, this small-scale study is one of the first to explore these three aspects collectively. As such, the current data suggest that more detailed research would be useful, both in seeking possible replication of the findings with a larger group of participants and also to understand the mechanisms of such possible linkage in terms of both basic research and also its implications for music pedagogy
A new neurosurgical tool incorporating differential geometry and cellular automata techniques
Using optical coherence imaging, it is possible to visualize seizure progression intraoperatively. However, it is difficult to pinpoint an exact epileptic focus. This is crucial in attempts to minimize the amount of resection necessary during surgical therapeutic interventions for epilepsy and is typically done approximately from visual inspection of optical coherence imaging stills. In this paper, we create an algorithm with the potential to pinpoint the source of a seizure from an optical coherence imaging still. To accomplish this, a grid is overlaid on optical coherence imaging stills. This then serves as a grid for a two-dimensional cellular automation. Each cell is associated with a Riemannian curvature tensor representing the curvature of the brain's surface in all directions for a cell. Cells which overlay portions of the image which show neurons that are firing are considered "depolarized"
âSing Every Dayâ: The wider benefits of a school-based singing project with disadvantaged children
The paper reports on a research evaluation of a six-month specialist singing project âSing Every Dayâ that was undertaken with young disadvantaged inner-city 6yo children in the London Borough of Hackney. A team of professional singers from the London-based VOCES8 Foundation visited two classes in each of two Primary schools to provide focused mentoring to generalist (non-music specialist) class teachers. Children from two identically aged classes in a neighbouring school acted as controls. The mentoring embraced a specially designed programme of singing and vocal activities across two school terms. This was undertaken in each classroom with the staff and their Year 1 children numbering N=121 in total. An independent evaluation of the impact of the project included both musical and other-than-musical measures of childrenâs development. In particular, in addition to an assessment of participant childrenâs singing behaviours at the start and at end of the project, other assessments included measures of possible changes in childrenâs reading development and in aspects of Executive Functions. Overall, the implications from the data are that the mentored classroom-based singing activities resulted in significant improvements in childrenâs singing, as well as positive changes in reading and aspects of Executive Function related to inhibition and phonological working memory â the latter being closely correlated to changes in the same childrenâs reading scores. Although there is previous research literature reporting positive links separately between music, singing, reading and aspects of Executive Functions, this small-scale study is one of the first to explore these three aspects collectively. As such, the current data suggest that more detailed research would be useful, both in seeking possible replication of the findings with a larger group of participants and also to understand the mechanisms of such possible linkage in terms of both basic research and also its implications for music pedagogy
Nitrogen fixation by caucasian clover and white clover in irrigated ryegrass pastures
The Nâ fixation ability of caucasian clover was
compared with that of white clover in irrigated
ryegrass pastures over years 2 and 3 of a grazing
experiment, using the Âčâ”N enrichment technique.
âEnduraâ caucasian clover was inoculated with
the specific Rhizobium strain ICC148. The N
concentration in clover herbage and the proportion
of clover N derived from Nâ fixation (PN) were
similar for both clovers at averages of 4.6%N and
50â60% respectively over the 2 years. The amount
of Nâ fixed per hectare was directly related to the
amount of clover dry matter (DM) produced by
the two clover species. Caucasian clover produced
four times the DM yield of white clover in year 2
(5400 cf. 1450 kg DM/ha) and four times the
amount of Nâ fixed in herbage (136 cf. 36 kg N/
ha). In year 3, caucasian clover produced 50%
more clover DM (3450 cf. 2370 kg DM/ha) and
Nâ fixed (98 cf. 66 kg N/ha) than white clover.
The increased N input from caucasian clover
increased grass %N and N uptake from soil in
caucasian clover pastures resulting in higher total
pasture production compared with white clover
pastures (15.7 cf. 14.2 t DM/ha) by year 3. In this
study, caucasian clover demonstrated greater
potential than white clover to meet the N demands
of high-yielding perennial ryegrass in an intensive
pastoral system.The authors acknowledge funding from the Struthers
Trust for the development of the grazing experiment at
Lincoln University and FRST funding for provision of
Âčâ¶N and N analyses. We thank the C. Alma Baker and Struthers
Trusts for providing A.D. Black with financial support
from post-graduate scholarships
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Modeling Checkpoint-Based Movement with the Earth Mover's Distance
Movement data comes in various forms, including trajectory data and checkpoint data. While trajectories give detailed information about the movement of individual entities, checkpoint data in its simplest form does not give identities, just counts at checkpoints. However, checkpoint data is of increasing interest since it is readily available due to privacy reasons and as a by-product of other data collection. In this paper we propose to use the Earth Moverâs Distance as a versatile tool to reconstruct individual movements or flow based on checkpoint counts at different times. We analyze the modeling possibilities and provide experiments that validate model predictions, based on coarse-grained aggregations of data about actual movements of couriers in London, UK. While we cannot expect to reconstruct precise individual movements from highly granular checkpoint data, the evaluation does show that the approach can generate meaningful estimates of object movements.
B. Speckmann and K. Verbeek are supported by the Netherlands Organisation for Scientific Research (NWO) under project nos. 639.023.208 and 639.021.541, respectively. This paper arose from work initiated at Dagstuhl seminar 12512 âRepresentation, analysis and visualization of moving objectsâ, December 2012. The authors gratefully acknowledge Schloss Dagstuhl for their support
Egg development, hatching rhythm and moult patterns in Paralomos spinosissima (Decapoda: Anomura: Paguroidea: Lithodidae) from South Georgia waters (Southern Ocean)
Larval release, hatching rhythms and moult patterns were examined in a captive population of the subantarctic lithodid, Paralomis spinosissima from the South Georgia and Shag Rocks region. Larvae hatched throughout the year with the majority of females starting to release larvae at the end of the austral summer and beginning of autumn. Larval release continued over a period of up to 9 weeks with high variability in the numbers that hatched each day. A similar seasonal pattern to hatching was evident in the moulting of females. Intermoult period for two adult females (CL = 63 and 85 mm) ranged from 894 to 1,120 days while an intermoult period for males was estimated to be in excess of 832 days. The results are consistent with other species of Paralomis and are discussed in relation to physiological and environmental adaptations to the cold-water conditions south of the Antarctic Convergence
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A conceptual framework for studying collective reactions to events in location-based social media
Events are a core concept of spatial information, but location-based social media (LBSM) provide information on reactions to events. Individuals have varied degrees of agency in initiating, reacting to or modifying the course of events, and reactions include observations of occurrence, expressions containing sentiment or emotions, or a call to action. Key characteristics of reactions include referent events and information about who reacted, when, where and how. Collective reactions are composed of multiple individual reactions sharing common referents. They can be characterized according to the following dimensions: spatial, temporal, social, thematic and interlinkage. We present a conceptual framework, which allows characterization and comparison of collective reactions. For a thematically well-defined class of event such as storms, we can explore differences and similarities in collective attribution of meaning across space and time. Other events may have very complex spatio-temporal signatures (e.g. political processes such as Brexit or elections), which can be decomposed into series of individual events (e.g. a temporal window around the result of a vote). The purpose of our framework is to explore ways in which collective reactions to events in LBSM can be described and underpin the development of methods for analysing and understanding collective reactions to events
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