Aircraft manoeuvring for sensor aiming

Airborne sensor aiming can be achieved with a fixed sensor using the manoeuvrability of an aircraft. Such a method offers advantages in potential sensor coverage and reduced payload complexity. Without use of a gimbal, an aircraft can be made more robust and sensor aiming is limited only by the aircraft flight capabilities. A novel method is developed and demonstrated for performing sensor aiming with a fixed-wing aircraft. A creative mathematical framework is presented for both a 3D path following controller and a method to seamlessly achieve sensor aiming while minimizing path deviation. A simulation environment is developed based on a fit-forpurpose aircraft model identified from live flight testing and the control algorithms are validated. Flight test data is presented demonstrating efficacy of the 3D path following controller. These demonstrations also serve to validate the aircraft modelling approach taken during controller development. Two application examples involving airborne radar aiming for detect and avoid and gimbal-less ground target tracking are used to illustrate the sensor aiming method. The proposed sensor aiming methodology is both practical and feasible as supported by results. The proposed method is applicable to both unmanned and manned aircraft. Future work involving the concept of manoeuvrable sensors is proposed in the conclusion

The water-energy nexus: quantifying the impact of water availability on future UK thermal power generation

A future lack of available water may compromise the UK’s current energy policy to meet an increasing demand for electricity with more thermal generation. This research asks what impact a lack of available water will have on UK thermal generation by 2050 and aims to quantify this impact in terms of cost, generation technology, and cooling method. The UK’s future national water demand for nine electricity generation pathways was modelled. The regional water demand of one pathway; the Energy Technologies Institute’s ESME.MC pathway was then modelled. This identified how technology and cooling method combinations drive demand and regionally, where the increase in water demand is likely to be greatest. The ESME.MC pathway was modified to allow the cost and technology implications of a lack of water to be modelled. This research found that relying on freshwater alone will constrain the contribution of thermal generation by 2050 and increase the annual cost of the UK energy system by £12.5bn. Using sea and estuarine water is a feasible mitigation option but will result in environmental trade-offs. It is recommended that when considering these trade-offs the societal and economic benefits of a cost competitive electricity generation system is given due weight

Stimulation characteristics that determine arteriolar dilation in skeletal muscle

Murrant, Coral L. Stimulation characteristics that determine arteriolar dilation in skeletal muscle. Am J Physiol Regul Integr Comp Physiol 289: R505-R513, 2005. doi:10.1152/ajpregu.00571.2004.-To determine the skeletal muscle stimulation parameters that are most important in establishing vasodilation in the microvasculature, I tested whether arteriolar diameter during 2 min of repetitive, short-duration, tetanic skeletal muscle contractions increased with changes in stimulus frequency, stimulation train duration, and contraction frequency. To test this, the diameter of transverse arterioles approximately perpendicular to small bundles of cremaster muscle fibers in situ of anesthetized Golden Syrian hamsters was used as a bioassay system. Arteriolar diameter was measured before and during different stimulation patterns that consisted of a contraction frequency [6, 12, or 24 contractions per minute (cpm)], a stimulation train duration (250, 500, or 750 ms) and a stimulus frequency Skeletal muscle metabolism has been hypothesized to be the source of dilators responsible for the vasodilation and resulting changes in blood flow in response to muscle contraction (for a review, see Refs. 11, In the present study, I sought to determine which stimulation characteristics of skeletal muscle were most influential in determining vasodilation in the microvasculature. To investigate this issue, a small bundle of skeletal muscle fibers in hamster cremaster muscle in situ was repetitively contracted with the chosen stimulation pattern for 2 min. The stimulation pattern was changed by systematically changing the parameters that comprise a tetanic contraction (contraction frequency, train duration and stimulus frequency). Stimulation parameters that are physiologically relevant to movement and locomotion were used where possible; this encompassed a range of stimulus frequencies within a train and short-train durations, under 1,000 ms depending on the nature of the activity METHOD

More integrity and less academic misconduct: The prevalence of academic misconduct during test re-grading of short and long answer tests

Many senior level science courses employ short and long answer testing style whereby students can have their test re-graded if they feel they were inaccurately assessed. The integrity of this type of system has been questioned over reports that students may alter their test before handing it back in for re-grading. We designed a study to objectively quantify the prevalence of this type of academic misconduct. Eleven third and fourth year science courses (class sizes: 63-468 students) that used a written testing style and allowed these tests to be re-graded were chosen for the study. All course midterm tests were graded and scanned before they were returned to the students, and then re-scanned if they were submitted for re-grading. The tests were then compared to determine if the answers had been altered. Ethical approval for this study was obtained to allow the study to be performed without informed consent to ensure the validity of the results. Further analysis will determine if there is a correlation between those that cheat and their test grade, their major, and their sex as well as observing how they are cheating. A comprehensive analysis of the all courses will help elucidate the context that incites students to commit academic misconduct. Understanding the prevalence of this cheating strategy, how students supplement their tests and the circumstances that provoke students to cheat will help us determine the integrity of this testing style, and inform us on how to deter this activity in the future

Real-Time Navigation for Autonomous Surface Vehicles In Ice-Covered Waters

Vessel transit in ice-covered waters poses unique challenges in safe and efficient motion planning. When the concentration of ice is high, it may not be possible to find collision-free trajectories. Instead, ice can be pushed out of the way if it is small or if contact occurs near the edge of the ice. In this work, we propose a real-time navigation framework that minimizes collisions with ice and distance travelled by the vessel. We exploit a lattice-based planner with a cost that captures the ship interaction with ice. To address the dynamic nature of the environment, we plan motion in a receding horizon manner based on updated vessel and ice state information. Further, we present a novel planning heuristic for evaluating the cost-to-go, which is applicable to navigation in a channel without a fixed goal location. The performance of our planner is evaluated across several levels of ice concentration both in simulated and in real-world experiments.Comment: 7 pages, 8 figure

Manipulation of environmental oxygen modifies reactive oxygen and nitrogen species generation during myogenesis

Regulated changes in reactive oxygen and nitrogen species (RONS) activities are important in maintaining the normal sequence and development of myogenesis. Both excessive formation and reduction in RONS have been shown to affect muscle differentiation in a negative way. Cultured cells are typically grown in 20% O2 but this is not an appropriate physiological concentration for a number of cell types, including skeletal muscle. The aim was to examine the generation of RONS in cultured skeletal muscle cells under a physiological oxygen concentration condition (6% O2) and determine the effect on muscle myogenesis. Primary mouse satellite cells were grown in 20% or 6% O2 environments and RONS activity was measured at different stages of myogenesis by real-time fluorescent microscopy using fluorescent probes with different specificities i.e. dihydroethidium (DHE), 4-amino-5-methylamino-2′,7′-difluorofluorescein diacetate (DAF-FM DA) and 5-(and-6)-chloromethyl-2′,7′ -dichlorodihydrofluorescein diacetate (CM-DCFH-DA). Data demonstrate that satellite cell proliferation increased when cells were grown in 6% O2 compared with 20% O2. Myoblasts grown in 20% O2 showed an increase in DCF fluorescence and DHE oxidation compared with myoblasts grown at 6% O2. Myotubes grown in 20% O2 also showed an increase in DCF and DAF-FM fluorescence and DHE oxidation compared with myotubes grown in 6% O2. The catalase and MnSOD contents were also increased in myoblasts and myotubes that were maintained in 20% O2 compared with myoblasts and myotubes grown in 6% O2. These data indicate that intracellular RONS activities in myoblasts and myotubes at rest are influenced by changes in environmental oxygen concentration and that the increased ROS may influence myogenesis in a negative manner

Promoting higher order thinking skills in biology: evaluation of a newly developed course using Bloom’s taxonomy.

We have recently designed and implemented a unique, large (1800 students/year) first year biological concepts of health course (BIOL*1080) aimed at promoting higher order thinking skills and attributes. Our course served as one of three courses that replaced two more traditional biology courses (BIOL*1030 and BIOL*1040) and incorporates seminar, lab and interdisciplinary assignments in an attempt to foster skills in areas such as oral and written communication, critical thinking, and independent learning. To determine if we were successful in designing a course centered on the teaching and assessment of higher order thinking skills, we ranked the course evaluative materials based on Bloom’s taxonomy (Zheng, A.Y., Science 319:414,2008). Bloom’s taxonomy is a hierarchical categorization of knowledge and thinking skills comprised of 6 levels (from lowest to highest): knowledge - 1, comprehension – 2, application – 3, analysis – 4, synthesis – 5, and evaluation – 6. Briefly, each exam question and assignment was scored by a team of 6 individuals with varying degrees of familiarity with the course. Scores per test/assignment were averaged and a weighted average was calculated for the entire course, with a higher weighted average representing assessment of a higher order of thinking. The average bloom level for our course was 3.28±0.15 which was significantly higher than one of the more traditional biology courses (BIOL*1030 – 1.93±0.08 ) but not the second course (BIOL*1040 – 2.95±0.17). The blooming exercise provided a useful metric to assess the level of higher order thinking required for newly developed courses and allowed for comparisons between courses to be objective