Effect of Our Galaxy's Motion on Weak Lensing Measurements of Shear and Convergence

In this work we investigate the effect on weak-lensing shear and convergence measurements due to distortions from the Lorentz boost induced by our Galaxy's motion. While no ellipticity is induced in an image from the Lorentz boost to first order in beta = v/c, the image is magnified. This affects the inferred convergence at a 10 per cent level, and is most notable for low multipoles in the convergence power spectrum C {\kappa}{\kappa} and for surveys with large sky coverage like LSST and DES. Experiments which image only small fractions of the sky and convergence power spectrum determinations at l > 5 can safely neglect the boost effect to first order in beta.Comment: 4 pages, replaced to reflect changes made for publication to MNRA

Setting safety stocks for stable rotation cycle schedules

The article of record as published may be found at http://dx.doi.org/10.1016/j.ijpe.2014.05.020In the process industries, specialized equipment and production processes often necessitate the manufacture of products in a pre-determined sequence to minimize change over time and to simplify scheduling complexity; these types of schedules are referred to as pure rotation schedules, or product wheels, where the circumference of the wheel is the production cycle length. In these industries change over times between the production of individual products can consume considerable time as well as raw materials and it is therefore often desirable to stabilize the production cycles in order to minimize unplanned change overs as well as quote accurate lead times to customers. Materials requirements planning (MRP) systems are often used to plan and coordinate production and supply resources with demand in these environments. Central to the effectiveness of the MRP system is the dependability of the lead time parameters. In this paper, we introduce an optimization model to determine safety stock levels that minimize long run expected costs where as table, cyclic schedule is used. Our model may be used strategically to assess inventory investment requirements as a function of capacity investment, product mix, production technology, demand volatility, and customer service levels. It may be used tactically to optimize item-level planning parameters such as lot size, safety stock and lead time in an MRP system and to support sales and operations planning(S&OP) processes where knowing the future costs associated with current decisions is highly desirable

Combining degradations: The effect of background noise on intelligibility of disordered speech

The effect of background noise on intelligibility of disordered speech was assessed. Speech-shaped noise was mixed with neurologically healthy (control) and disordered (dysarthric) speech at a series of signal-to-noise ratios. In addition, bandpass filtered control and dysarthric speech conditions were assessed to determine the effect of noise on both naturally and artificially degraded speech. While significant effects of both the amount of noise and the type of speech were revealed, no interaction between the two factors was observed, in either the broadband or filtered testing conditions. Thus, it appears that there is no multiplicative effect of the presence of background noise on intelligibility of disordered speech relative to control speech. That is, the decrease in intelligibility due to increasing levels of noise is similar for both types of speech, and both types of testing conditions, and the function for dysarthric speech is simply shifted downward due to the inherent source degradations of the speech itself. Last, large-scale online crowdsourcing via Amazon Mechanical Turk was utilized to collect data for the current study. Findings and implications for this data and data collection approach are discussed

Helping Students Make Informed Decisions About Transition Via Web-Based Resources

Although there are many transitions that occur in a young person’s life, transition from high school to adulthood can be one of the most challenging. This transition requires autonomy and decision-making skills. To support youth in having positive outcomes after high school, it is imperative for teachers to have strategies to guide students in making informed decisions as they begin the transition process. This article provides teachers with strategies and resources to help youth build autonomy, make informed decisions, and gain information via web-based resources to support the transition from high school into postschool life. Steps for building autonomy, evaluating web-based resources, and investigating web-based resources to support transition are included

Metabolic Flexibility and Weight Status May Contribute to Inter-Individual Changes in Breastmilk Lipid Content in Response to an Acute Bout of Exercise: Preliminary Findings from a Pilot Study

International Journal of Exercise Science 13(2): 1756-1769, 2020. The purposes of this pilot study were to describe changes in breastmilk lipid content in response to an acute bout of moderate intensity exercise and to explore maternal metabolic health factors, including metabolic flexibility, which may impact this change. A cross-sectional, observational, pilot study design was performed in 14 women between 4 and 6 months postpartum. Whole body fasting lipid oxidation was assessed, a standardized high-fat breakfast was consumed, and lipid oxidation was again measured 120-minutes post-meal. Metabolic flexibility was determined by comparing the change in lipid oxidation before and after the meal. Women completed 30-minutes of moderate intensity treadmill walking 150-minutes post-meal. Breastmilk was expressed and analyzed for lipid content before and after exercise. Overall, there was no significant difference between pre- and post-exercise breastmilk lipid content (pre-exercise 59.4±36.1 g/L vs. post-exercise 52.5±20.7 g/L, p=0.26). However, five (36%) women had an increase in breastmilk lipid content in response to the exercise bout, compared to nine (64%) that had a decrease in breastmilk lipid content suggesting inter-individual variability. The change in breastmilk lipid content from pre- to post-exercise was positively correlated to metabolic flexibility (r=0.595, p=0.03). Additionally, post-exercise lipid content was positively correlated with body mass index (BMI), body composition, and postpartum weight retention. Preliminary findings from this pilot study suggest that metabolic flexibility and maternal weight status may help explain the inter-individual changes in breastmilk lipid content in response to an acute bout of moderate intensity exercise

Mixed Student Ideas about Mechanisms of Human Weight Loss

Recent calls for college biology education reform have identified “pathways and transformations of matter and energy” as a big idea in biology crucial for students to learn. Previous work has been conducted on how college students think about such matter-transforming processes; however, little research has investigated how students connect these ideas. Here, we probe student thinking about matter transformations in the familiar context of human weight loss. Our analysis of 1192 student constructed responses revealed three scientific (which we label “Normative”) and five less scientific (which we label “Developing”) ideas that students use to explain weight loss. Additionally, students combine these ideas in their responses, with an average number of 2.19 ± 1.07 ideas per response, and 74.4% of responses containing two or more ideas. These results highlight the extent to which students hold multiple (both correct and incorrect) ideas about complex biological processes. We described student responses as conforming to either Scientific, Mixed, or Developing descriptive models, which had an average of 1.9 ± 0.6, 3.1 ± 0.9, and 1.7 ± 0.8 ideas per response, respectively. Such heterogeneous student thinking is characteristic of difficulties in both conceptual change and early expertise development and will require careful instructional intervention for lasting learning gains

Synchrotron light source X-ray detection with Low-Gain Avalanche Diodes

The response of Low Gain Avalanche Diodes (LGADs), which are a type of thin silicon detector with internal gain, to X-rays of energies between 6-70 keV was characterized at the SLAC light source (SSRL). The utilized beamline at SSRL was 11-2, with a nominal beam size of 3 cm x 0.5 cm, a repetition rate of 500 MHz, and very monochromatic. LGADs of different thicknesses and gain layer configurations were read out using fast amplification boards and digitized with a fast oscilloscope. Standard PiN devices were characterized as well. The devices' energy resolution and time resolution as a function of X-ray energy were measured. The charge collection and multiplication mechanism were simulated using TCAD Sentaurus, and the results were compared with the collected data.Comment: 18 pages, 18 figure

A Stochastic Inventory Model for the Stock Versus Non-Stock Decision

The most fundamental decision in inventory management is whether or not to stock a particular item. Despite its importance, the preponderance of the literature on inventory systems is concerned with how much to order and when to order which assume the stocking decision has been made. In this research we examine an inventory stocking decision model that is based upon an item’s demand history. In this model every item must earn its way into the catalogue of stocked items by receiving a given number of demands over a specified time period and will likewise be de-stocked and taken out of the catalogue (or burned) if it receives fewer than a given number of demands over a specified time period. We show the stability of such a policy and discuss implications for its use by firms that compete on product assortment. This research should be of interest to the Department of Defense as well as commercial firms that have large numbers of items in their product catalogues

Estimates of Unit Cost Reductions of the F-16 Fighter as a Result of U.S. Arms Export Production

The article of record as published may be found at http://dx.doi.org/10.1080/1941658X.2013.766547Arms exports have increasingly become an attractive option for reducing escalating unit costs of new weapon systems to the United States Department of Defense. However, while there is no lack of conjecture, there is little data that show weapon system costs to the United States actually decrease when the same weapon is sold to a foreign buyer. The authors use the sale of the F-16 multi-role fighter aircraft to foreign nations as a case study to quantify the financial gains realized through learning and economies of scale attributed to export production. Using a rate-adjustment cost improvement analysis, the authors’ case study shows the unit costs the United States Department of Defense would have incurred without the concurrent export production of F-16s. Estimates suggest that the production savings resulting from export production were in excess of the research, development, test, and evaluation costs of the F-16 for the period 1975 to 1991. The potential benefits associated with keeping the F-16 production line “warm” through export production and the limits of applying the findings to other weapon systems are discussed.Office of the Undersecretary of DefenseAerospace Industries Associatio