Advanced sun-sensor processing and design for super-resolution performance

The performance of conventional and parametric super-resolution algorithms for estimating sun position in a spacecraft sun-sensor was analyzed. Widely employed in other applications, parametric algorithms were examined to evaluate increase in system performance without affecting the cost of the sensor system. Using a simplified model of detector illumination simulations provided quantitative comparisons of algorithm performance. Simple sensor re-design was examined by using genetic algorithms as a heuristic to optimize the illumination pattern for a single axis digital sun-sensor. Findings show that, multiple narrow peak patterns provide subpixel accuracy in resolving the sun-angle. The optimal illumination pattern can be implemented by fabricating a replacement aperture mask for the sensor and this change can be made at a minimal cost. The super-resolution algorithms were tested with a component noise model and image degradation due to Earth albedo effects were examined. Parametric algorithms display very good performance throughout the test regime. The improvements are substantial enough to validate this approach worthy of future study.

Advanced sun-sensor processing and design for super-resolution performance

The performance of conventional and parametric super-resolution algorithms for estimating sun position in a spacecraft sun-sensor was analyzed. Widely employed in other applications, parametric algorithms were examined to evaluate increase in system performance without affecting the cost of the sensor system. Using a simplified model of detector illumination simulations provided quantitative comparisons of algorithm performance. Simple sensor re-design was examined by using genetic algorithms as a heuristic to optimize the illumination pattern for a single axis digital sun-sensor. Findings show that, multiple narrow peak patterns provide subpixel accuracy in resolving the sun-angle. The optimal illumination pattern can be implemented by fabricating a replacement aperture mask for the sensor and this change can be made at a minimal cost. The super-resolution algorithms were tested with a component noise model and image degradation due to Earth albedo effects were examined. Parametric algorithms display very good performance throughout the test regime. The improvements are substantial enough to validate this approach worthy of future study.

“Advocacy cheating”: teacher noncompliance in standardised literacy testing

Purpose The purpose of this paper is to explore teachers’ noncompliance with secondary-level standardised literacy testing in Tasmania, Australia, particularly their motivations, behaviours and justifications. This paper challenges pervasive views regarding test noncompliance, suggesting a reframing as “advocacy cheating”: noncompliance for purposes of advocating for and supporting students. Design/methodology/approach The research used a single case study design, with a simple thematic analysis of the qualitative data. The design enabled data to be collected during one iteration of the examined test regime, with depth of exploration into participants’ experiences and perspectives. Findings Findings indicate that small number of participants were engaged in test rule noncompliance at all stages of the testing regime: before, during and following the tests. This paper presents the concept of “advocacy cheating”, illustrated in these data through the motivations presented by participants for their noncompliant actions and the forms of noncompliance used. Research limitations/implications The small sample size and single site problematise drawing much broader comparisons. The age of the data means that current test processes and requirements have developed. Larger-scale studies might enable identification of ways in which this current regime has and might be improved. Practical implications This study’s findings and its focus on the classroom and teacher experience of testing provide insights into a widely debated and publicly important phenomenon. Originality/value The concept of “advocacy cheating” provides a newer way of considering and interpreting the range of ways in which teachers implement standardised tests.

Algeria's new generation could test regime transition

Subject Changing undercurrents in Algeria society and their potential impact. Significance The decline in oil prices and reduced government revenues have brought uncertainty about the country's future back to the surface. Algerian media has been reporting daily on the economic effects of decreased oil and gas revenues, which account for 60% of total budget revenue in the past three years. Coupled with instability in neighbouring Libya and Mali, and rare domestic unrest in Ghardaia, Algiers is keen to give the impression that it is addressing the nation's problems. However, it is has struggled to respond to these pressures as the country's underlying fundamentals are changing. Impacts The ruling elite will avoid cutting subsidies despite the financial pressures. Entrepreneurs may gain increasing their influence in politics. A change in the balance of power away from the army and towards the president and business elite could undercut state security.

Adsorption Modeling of Fatty and Oleic Estolide Esters via Boundary Lubrication Coefficient of Friction Measurements

The frictional behaviors of a variety of fatty esters (methyl palmitate (MP), methyl laurate (ML), and 2-ethylhexyl oleate (EHO)) and oleic estolide esters (methyl oleic estolide ester (ME) and 2-ethylhexyl oleic estolide ester (EHE)) as additives in hexadecane have been examined in a boundary lubrication test regime using steel contacts. Critical additive concentrations were defined and used to perform novel and simple Langmuir analyses that provide an order of adsorption energies: EHE ≥ ME > EHO > MP > ML. Application of a general adsorption model indicates slight cooperative adsorption of EHE, ME, and EHO. MP and ML data require larger attractive interaction terms (α ≤ −2.3) to be adequately fit. Irrespective of ester functionality increasingly negative adsorption energies appear to correlate with molecular weight. This suggests that multiple site coverage and multiple adsorptive interactions are likely for each of the esters studied.

Gain efficiency in short-term testing: experimental results

Height growth of loblolly pine (Pinustaeda L.) was measured in trees subjected to one of five irrigation and fertilization regimes in a closely spaced genetic test for 3 years. Shoot components of 3rd-year annual height increment were measured over two contrasting treatments. Juvenile height and number of stem units in summer growth length in the fully irrigated and fertilized short-term test regime exhibited (i) the highest juvenile-mature correlations (family mean correlation = 0.41–0.68), (ii) high individual-tree heritabilities (0.38–0.44), which were two- to three-fold higher than older tree values in a conventional genetic test of the same families, (iii) high genetic stability across two extreme short-term test treatments (genetic correlation = 0.61–0.80), and (iv) an efficiency in genetic gain per generation of 81–87% relative to selection on height at age 8 years.

Substrate metabolism in seasonally acclimatized American goldfinches

Concentration of ([Glc]) and turnover (Ro) of plasma glucose, concentration of free fatty acids in plasma ([FFA]), and concentration of glycogen in muscle and liver were measured in freshly captured summer- and winter-acclimatized American goldfinches (Carduelis tristis). These birds were acutely exposed to one of three thermal regimes: 1) “thermoneutral,” 30 degrees C in air, 2) “cold,” -15 degrees C in air, and 3) “severe cold,” 0 degrees C in 79% He and 21% O2. Additionally, the activities of citrate synthase (CS), phosphofructokinase (PFK), and beta-hydroxyacyl-CoA dehydrogenase (HOAD) were measured in pectoralis and leg muscles of winter and summer birds. Ro for goldfinches at 30 degrees C is unchanged between winter and summer, whereas it is 25% lower at -15 degrees C in winter than in summer birds, even though rates of heat production are similar. Additionally, winter animals depleted muscle glycogen at slower rates than summer individuals when exposed to “cold” or “severe cold.” [Glc] and [FFA] for each test regime did not vary between seasons. The activity of the beta-oxidative enzyme HOAD is the pectoralis muscle (the main thermogenic tissue) increases by 50% from summer to winter, but the activities of PFK and CS remain essentially constant. We conclude that the ability to restrict carbohydrate use under cold stress is a component of the winter acclimatization process in the American goldfinch. One mechanism which might foster this ability in the increase in beta-oxidative capacity of the flight muscles, permitting a greater reliance on fatty acids by winter animals during cold-induced thermogenesis.