Laser angle measurement system

The design and fabrication of a laser angle measurement system is described. The instrument is a fringe counting interferometer that monitors the pitch attitude of a model in a wind tunnel. A laser source and detector are mounted above the mode. Interference fringes are generated by a small passive element on the model. The fringe count is accumulated and displayed by a processor in the wind tunnel control room. Optical and electrical schematics, system maintenance and operation procedures are included, and the results of a demonstration test are given

A theoretical investigation of the propagation of TEno-waves in dielectrically loaded waveguides

The propagation of Teno nodes in rectangular wave-guids that contain two dielectric slabs parallel to the slide walls and extending over the full height of the guide is theorhetically investigated

The Use of Journaling to Assess Student Learning and Acceptance of Evolutionary Science

Journal writing was introduced as a means to assess student learning and acceptance of evolutionary science in a nonmajors’ biology course taught at a community college. Fourteen weeks of instruction were performed, each initiated by student-centered, in-class activities and culminated by a discussion, to elucidate tentative conclusions based on evidence from in-class activities. Students (N = 31) engaged in explicit and reflective writing (i.e., journaling) at four points during the semester, providing responses to the following questions: (a) what influence did the recent inclass activities and discussion have on your understanding of evolution (b) has your view (of evolution) changed (explain your response and provide support or examples of what influenced the change); and (c) what aspects of the nature of science have your observed in recent lessons/activities. Journal entries were coded on a continuum as informed (I), somewhat informed (SWI), or not informed (NI) regarding the accuracy of evidence cited with respect to evolutionary science. Initial journal entries were judged as strongly NI and highly negative toward evolution. Data analyses at the conclusion of the course, however, indicated a statistically significant shift in student responses toward an informed view more consistent with evolutionary principles and less personally resistant to biological evolution

B704: Costs and Returns on Maine Apple Farms

The purpose of this study was to collect data relative to the costs of growing, harvesting, storing, and packing apples in Maine, to analyze the factors affecting costs and returns, and to provide Maine apple producers with current information for adjusting farm resources to achieve optimum efficiency in production under rapidly changing economic conditions. This study was undertaken to determine the profitability of Maine apple farms, and to determine the current size and scope of the Maine apple industry. The results and implications of this study should be useful to all concerned with the apple industry in Maine and New England.https://digitalcommons.library.umaine.edu/aes_bulletin/1133/thumbnail.jp

The Congregation\u27s Right to Choose Its Pastor

The image of the pastor or religious leader, his authority, function and role, is currently a lively topic for discussion, as church groups merge and emerge, as clergy are robed and disrobed, as town and gown and church and state issues erupt and disrupt the peace of the church and the parish. Therefore this translation of Carl Ferdinand Wilhelm Walther\u27s essay, Das Gemeindewahlrecht, delineating the voting rights of the congregation, appears at an appropriate time. The Lutheran Church-Missouri Synod has not beenhttps://scholar.csl.edu/ebooks/1036/thumbnail.jp

X-ray and Laser Investigation of High Pressure Sprays

The diagnostics of multiphase flows is important to understand the correlation of parameters such as nozzle geometry, flow velocity, liquid breakup characteristics, atomization, and mass distribution. Investigation of each of these parameters can lead to various improvements on design and optimization, for example, of combustion in gas turbines and rocket engines. For this project, the X-ray and optical diagnostics of multiphase flows in propulsion is investigated for high pressures. Two x-ray tube sources are used to illuminate the spray, and the images are captured on phosphor plates coupled to high-speed cameras. Reconstruction of the mass distribution is accomplished using computer analysis by applying Beer’s-Lambert law. High temporal resolution and spatial resolution images were collected of various sprays composed of water and KI solutions for development and characterization of the technique with different window materials typically used in high-pressure vessels. Laser-based fluorescence was tested in vaporized jet-A fuel in a high-pressure vessels. The implications for X-ray and laser analysis of multiphase flows in sprays with high spatial and temporal resolution and high signal to noise ratio are investigated

Jobs 4.0: Are Botswana Workers Ready?

This paper attempts to unravel the potential social effects of the fourth industrial revolution (4IR) on Botswana employees. The authors investigated employees’ level of awareness and preparedness for an era of full blown 4IR adoption. Utilizing purposive sampling, a self-administered questionnaire was distributed to a sample of 52 employees in Gaborone. This work employed the Unified Theory of Acceptance and Use of Technology model (UTAUT). The major findings of the study are: 50% of respondents confirmed their preparedness for the adoption of 4IR technologies; 48% believed that the rest of employees in their organization were prepared for 4IR; 65% said they were prepared to embrace and take advantage of the efficiencies brought about by 4IR; job roles are likely to change significantly with some roles disappearing and new roles emerging; and critical thinking, complex problem solving, innovation and digital related skills are bound to be more in demand. The outcomes of this research will serve as a wakeup call to Botswana employees, to equip themselves and future generations with requisite skills, for the changing roles. Furthermore, organizations will also use the outcomes to consider reskilling their employees accordingly. For educators, the study will encourage consideration and alignment of the curricular while in terms of and for policy formulation, it will engender reflecting on the regulatory frameworks to align them to the demands of the new era.Keywords: Fourth Industrial Revolution, industry 4.0, jobs4.0, future of jobs DOI: 10.7176/DCS/11-2-05 Publication date: February 28th 202

The 50 Ah NiH2 CPV qualification tests

In 1992, the Naval Research Laboratory (NRL) started a program to qualify a large diameter common pressure vessel (CPV) nickel-hydrogen (NiH2) batteries for use on future Navy/NRL spacecraft electrical power subsystems. NRL's involvement with the qualification of CPV NiH2 batteries dates back to 1988 when COMSAT and Johnson Controls, Inc. initiated a joint effort to fly the first ever NiH2 CPV in space. A later NRL-JCI cooperative research and development agreement led to the launch of a space experiment in 1993 and to the use of a single NiH2 CPV battery on the BMDO Clementine spacecraft in 1994. NRL initiated procurement of two, 50 Ah CPV NiH2 batteries in the Fall of 1992. The two batteries were delivered to NRL in June 1994. NiH2 CPV batteries have almost 2x the specific energy (Wh/kg) of nickel cadium batteries and 2x the energy density (Wh/l) of individual pressure vessel NiH2 CPV's. This presentation discusses the results of electrical and mechanical qualification tests conducted at NRL. The tests included electrical characterization, standard capacity, random vibration, peak load, and thermal vacuum. The last slides of the presentation show initial results from the life cycle tests of the second NiH2 CPV battery at 40% depth of discharge and a temperature of 10 C

Optimization of a High-Speed X-Ray Imaging System for Studying Sprays

Spray-based liquid atomization and liquid mixing is critical for development of efficient combustors and drug delivery systems as well as multiple coating-related applications. While optical methods allow characterization of low density regions of sprays, the scattering of optical photons hinders the characterization of a dense core. Unlike optical photons, higher-energy X-ray photons have the capability to penetrate and image the core structure of sprays. Here we characterized temporal and spatial resolution of an X-Ray imaging system based on a commercially available tube source with an anode size of 0.6 mm. For high-speed imaging, a phosphor screen in combination with a high-speed CMOS camera equipped with a two-stage intensifier was used. Water was used as a model liquid with the addition of potassium iodide to increase the X-Ray absorption coefficient. Two-dimensional images of 0.5mm and 2 mm impinging jet sprays were taken with differing spatial resolutions and potassium iodide mass concentrations. Depending on the spray conditions, optimal imaging settings were found. The technique can be extended to three-dimensional analysis of sprays with multiple viewing angles from two or more X-ray sources along with tomographic reconstruction