A technique for dynamically calibrating pressure transducers at cryogenic temperatures

A technique was developed for the calibration of dynamic pressure transducers at cryogenic temperatures. The calibration system utilizes an 8.9 Newton peak thrust shaker which oscillates a helium-filled bellows to generate a sinusoidal dynamic pressure to calibrate transducers immersed in a cryogenic environment. The system has a dynamic pressure measurement uncertainty of approximately 11% and is capable of producing peak-to-peak dynamic pressure amplitudes of 1.4 kPa over a frequency range of 40 to 100 hertz and a temperature range of 100 to 300 K. It provides an unprecedented capability of both static and dynamic calibration of pressure transducers from ambient to cryogenic temperature

Optimal control of storage for arbitrage, with applications to energy systems

We study the optimal control of storage which is used for arbitrage, i.e. for buying a commodity when it is cheap and selling it when it is expensive. Our particular concern is with the management of energy systems, although the results are generally applicable. We consider a model which may account for nonlinear cost functions, market impact, input and output rate constraints and inefficiencies or losses in the storage process. We develop an algorithm which is maximally efficient in then sense that it incorporates the result that, at each point in time, the optimal management decision depends only a finite, and typically short, time horizon. We give examples related to the management of a real-world system.Comment: 7 pages, 6 figure

Center for Rural Health

This departmental history was written on the occasion of the UND Quasquicentennial in 2008.https://commons.und.edu/departmental-histories/1068/thumbnail.jp

Students\u27 Perceptions of Online Equine Courses and Their Impacts on Learning Outcomes

Post-secondary education is always changing and evolving. Over the last few years, significant changes in education have resulted in an increased number of online courses. Approximately 28% of students seeking higher education participate in at least one online course and 14% are enrolled exclusively in distance or online programs (Allen & Seaman, 2016). However, courses that are typically hands-on, like equine science, may be more challenging online. The hands-on experiences in equine science classes help prepare students for future careers. Due to an increase in students choosing to take courses online, a review of online teaching methods was conducted to determine students\u27 preferred teaching tools in an online equine course. The survey was sent out to approximately 10 universities that offer equine science courses online through members of the National Association of Equine Affiliated Academics (NAEAA) and equine program directors to solicit student participation. Participation was limited to college students that had previously or were currently enrolled in an online equine-focused course and was completely voluntary. Of the 77 respondents, 71 (92%) were female, 6 (8%) males, and the majority (96%) white. The primary reasons students chose an online equine science course was because it fit their schedule better (n = 8; 24.5%) and the course was only offered online (n = 36; 23.2%). Students found videos (n = 62; 92.5%) and readings (n = 57; 85.1%) were extremely or somewhat beneficial teaching methods in online equine courses. Half (n = 34; 50.8%) of the students felt they learned as much in their online courses as in a traditionally taught equine course. Additionally, students indicated they received a quality education in equine science courses whether taught online (n = 55; 82.1%) or in a traditional in-person (n = 49; 73.1%) format. Advisor: Lisa Karr and Lena Luc

An Investigation of The Raman Effect and The Percentage of Light Transmitted With Certain Wavelength Limits For Ten New Chemical Compounds

Since the discovery of the Raman effect many substances (5), (7) have been studied to determine their effect on the scattering of light. Although the Raman effect is essentially physical in nature , it comprises another means by which the behavior of atoms within molecules and the behavior of the molecules themselves may be determined independently of their state of aggregation. The discovery of the Raman effect gave new impetus to the work of the theoretical physicist and was an important factor in the rapid development ma.de in the quantum theory since the time of its discovery

Root and Top Development of Five Native Kansas Legumes From Seed To End of The First Season

This study was undertaken to obtain more basic information about top and root development during the first season. The plants selected for study were: Petalostemon purpureus (purple prairie clover), Petalostemon candidus (white prairie clover), Psoralea tenuiflora (wild alfalfa), Psoralea cuspidata (prostrate wild alfalfa), and Vicia americana linearis (vetch). Vetch is given as Vicia sparsifolia in Rydberg (1932) but the seeds received were labeled as above and this name was retained. In the following pages it is referred to as Vicia americana for briefness