4,539 research outputs found
Challenges of Technique and Interpretation: a Performance Guide to Selected Works by Kevin Bobo
Kevin Bobo is an American percussionist and composer whose compositions for marimba consistently expand the technical and musical potential of the instrument. Performance of Bobo’s marimba works requires the performer to utilize specific performance techniques that are departures from standard practices. This study looks in- depth at technical and interpretive challenges present within three works for marimba by Bobo, and provides the performer with detailed explanations and exercises to assist with the performance of the included works. The Odyssey, According to Penelope, and Three Etudes are works for solo marimba, while Prayer for the Broken is a duet for two marimbas. Each work is distinctive in its harmonic makeup, melodic motifs, and rhythmic patterns. Additionally, each piece explores distinct technical challenges, all of which showcase the breadth of Bobo’s compositional style, justifying their inclusion in this study. Through this study, the author aims to provide percussionists with a greater understanding of his music, thus demystifying it and encouraging increased performance of Bobo’s works
Quantifying Operational Constraints of Low-Latency Telerobotics for Planetary Surface Operations
NASA's SLS and Orion crew vehicle will launch humans to cislunar space to
begin the new era of space exploration. NASA plans to use the Orion crew
vehicle to transport humans between Earth and cislunar space where there will
be a stationed habitat known as the Deep Space Gateway (DSG). The proximity to
the lunar surface allows for direct communication between the DSG and surface
assets, which enables low-latency telerobotic exploration. The operational
constraints for telerobotics must be fully explored on Earth before being
utilized on space exploration missions. We identified two constraints on space
exploration using low-latency surface telerobotics and attempts to quantify
these constraints. A constraint associated with low-latency surface
telerobotics is the bandwidth available between the orbiting command station
and the ground assets. The bandwidth available will vary during operation. As a
result, it is critical to quantify the operational video conditions required
for effective exploration. We designed an experiment to quantify the threshold
frame rate required for effective exploration. The experiment simulated
geological exploration via low-latency surface telerobotics using a COTS rover
in a lunar analog environment. The results from this experiment indicate that
humans should operate above a threshold frame rate of 5 frames per second. In a
separate, but similar experiment, we introduced a 2.6 second delay in the video
system. This delay recreated the latency conditions present when operating
rovers on the lunar farside from an Earth-based command station. This time
delay was compared to low-latency conditions for teleoperation at the DSG
(0.4 seconds). The results from this experiment show a 150% increase in
exploration time when the latency is increased to 2.6 seconds. This indicates
that such a delay significantly complicates real-time exploration strategies.Comment: 10 pages, 8 figures, Proceedings of the IEEE Aerospace Conference,
Big Sky, MT. arXiv admin note: text overlap with arXiv:1706.0375
Coastal adaptations and submerged landscapes : Where world prehistory meets underwater archaeology
Studies in world prehistory, which include the transition between the Pleistocene and Holocene and the cultural shift from Forager to Farmer, remain incomplete, particularly along the coastal margins. Submerged landscape archaeology has begun to emerge as a serious sub-discipline of both maritime archaeology and world prehistory, with a largely untapped potential to fill in significant gaps in the archaeological record. This chapter reviews the current state of submerged landscape archaeology and considers important elements, both theoretical and practical, and discusses how future generations of prehistorians must be willing and able to engage with archaeology on the continental shelves, worldwide
Biological and integrated control of musk thistle in Missouri (2001)
"New 8/01/5M.""Integrated pest management.""The authors acknowledge the work of William Dierker (retired), Mahlon L. Fairchild (retired), James H. Jarman (University Outreach and Extension, Callaway County), and Richard McDonald (Symbiont, Sugar Grove, N.C.) in the development of this guide.""This publication replaces MU publication G4867, Integrated Control of Musk Thistle Using an Introduced Weevil.""Weed control.
Effects of breaking up prolonged sitting following low and high glycaemic index breakfast consumption on glucose and insulin concentrations
Purpose: Breaking up prolonged sitting can attenuate the postprandial rise in glucose and insulin. Whether such effects are dependent of the glycaemic index (GI) of the consumed carbohydrate is unknown. This study examined the acute effects of breaking up prolonged sitting following a low GI and a high GI breakfast on postprandial glucose and insulin concentrations. Procedures: Fourteen adult males aged 22.1 ± 1.2 years completed four, 4 h experimental conditions: high GI breakfast followed by uninterrupted sitting (HGI-SIT), low GI breakfast followed by uninterrupted sitting (LGI-SIT), high GI breakfast followed by 2 min activity breaks every 20 min (HGI-ACT), and low GI breakfast followed by 2 min activity breaks every 20 min (LGI-ACT). Positive incremental area under the curve (iAUC) for glucose and insulin (mean [95% CI]) for each 4h experimental condition was calculated. Statistical analyses were completed using linear mixed models. Results: The sitting × breakfast GI interaction was not significant for glucose positive iAUC (P=0.119). Glucose positive iAUC (mmol/L4 h−1) was significantly lower in the activity breaks conditions than the uninterrupted sitting conditions (2.07 [2.24, 2.89] vs. 2.56 [1.74, 2.40], respectively, P=0.004) and significantly lower in the low GI conditions than the high GI conditions (2.13 [1.80, 2.45] vs. 2.51 [2.18, 2.84], respectively, P=0.022). Insulin concentrations did not differ between conditions (P ≥ 0.203). Conclusions: Breaking up prolonged sitting and lowering breakfast GI independently reduced postprandial glucose responses. This indicates that interrupting prolonged sitting and reducing dietary GI are beneficial approaches for reducing cardiometabolic disease risk
MOOCs Meet Measurement Theory: A Topic-Modelling Approach
This paper adapts topic models to the psychometric testing of MOOC students
based on their online forum postings. Measurement theory from education and
psychology provides statistical models for quantifying a person's attainment of
intangible attributes such as attitudes, abilities or intelligence. Such models
infer latent skill levels by relating them to individuals' observed responses
on a series of items such as quiz questions. The set of items can be used to
measure a latent skill if individuals' responses on them conform to a Guttman
scale. Such well-scaled items differentiate between individuals and inferred
levels span the entire range from most basic to the advanced. In practice,
education researchers manually devise items (quiz questions) while optimising
well-scaled conformance. Due to the costly nature and expert requirements of
this process, psychometric testing has found limited use in everyday teaching.
We aim to develop usable measurement models for highly-instrumented MOOC
delivery platforms, by using participation in automatically-extracted online
forum topics as items. The challenge is to formalise the Guttman scale
educational constraint and incorporate it into topic models. To favour topics
that automatically conform to a Guttman scale, we introduce a novel
regularisation into non-negative matrix factorisation-based topic modelling. We
demonstrate the suitability of our approach with both quantitative experiments
on three Coursera MOOCs, and with a qualitative survey of topic
interpretability on two MOOCs by domain expert interviews.Comment: 12 pages, 9 figures; accepted into AAAI'201
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