11,048 research outputs found
Tables of two-sided tolerance factors for normal distributions
Tables of two-sided tolerance factors for normal distribution
An Automated Technique for Estimating Daily Precipitation over the State of Virginia
Digital IR and visible imagery obtained from a geostationary satellite located over the equator at 75 deg west latitude were provided by NASA and used to obtain a linear relationship between cloud top temperature and hourly precipitation. Two computer programs written in FORTRAN were used. The first program computes the satellite estimate field from the hourly digital IR imagery. The second program computes the final estimate for the entire state area by comparing five preliminary estimates of 24 hour precipitation with control raingage readings and determining which of the five methods gives the best estimate for the day. The final estimate is then produced by incorporating control gage readings into the winning method. In presenting reliable precipitation estimates for every cell in Virginia in near real time on a daily on going basis, the techniques require on the order of 125 to 150 daily gage readings by dependable, highly motivated observers distributed as uniformly as feasible across the state
Photogrammetry-Based Analysis of the On-Orbit Structural Dynamics of the Roll-Out Solar Array
The Roll-Out Solar Array (ROSA) flight experiment was launched to the International Space Station (ISS) on June 3rd, 2017. ROSA is an innovative, lightweight solar array with a flexible substrate that makes use of the stored strain energy in its composite structural members to provide deployment without the use of motors. This paper will discuss the results of various structural dynamics experiments conducted on the ISS during the weeks following launch. Data gathered from instrumentation on the solar array wing during the experiments was previously compared with pre-flight predictions from two different Finite Element Modeling (FEM) efforts. In this paper, data generated from photogrammetry is compared with accelerometer data and used to extend previous conclusions. Whereas previous analyses were only able to track the accelerations of six discrete points on the structure and photovoltaic (PV) blanket of ROSA, the photogrammetry analysis makes available displacements for dozens of points distributed throughout the array. This larger data set makes it possible to compare higher-order PV blanket modes with FEM predictions, in addition to verifying conclusions reached using accelerometer data. The goal in this effort was to better understand the performance of ROSA and to improve modeling efforts for future designs of similar solar arrays
Herman Melville and the mid-nineteenth-century : the narrator and the literary politics of class dissent in the first six novels.
SIGLEAvailable from British Library Document Supply Centre- DSC:D171689 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Observations on Social and Psychological Deterrents to the Production of Low-Cost Housing in the United States
Alien Registration- Chamberlain, Mary A. (Lewiston, Androscoggin County)
https://digitalmaine.com/alien_docs/29382/thumbnail.jp
A Semester Long Classroom Course Mimicking a Software Company and a New Hire Experience for Computer Science Students Preparing to Enter the Software Industry
Students in a Computer Science degree programs must learn to code before they can be taught Software Engineering skills. This core skill set is how to program and consists of the constructs of various languages, how to create short programs or applications, independent assignments, and arrive at solutions that utilize the skills being covered in the language for that course (Chatley & Field, 2017). As an upperclassman, students will often be allowed to apply these skills in newer ways and have the opportunity to work on longer, more involved assignments although frequently still independent or in small groups of two to three students. Once these students graduate and enter the software industry they will find that most companies follow specific development methodologies from one of the many forms of Agile through Waterfall. All while working in large groups or teams where each developer is responsible for specific pieces of the functionality, participating in design meetings and code reviews, as well as using code versioning systems, such as git, a program management system, such as Jira, all in a very collaborative environment. This study will develop a course that will allow students to apply these skills in a more realistic setting while remaining on-campus and monitoring the students’ beliefs on their preparedness for the world outside of the computer science building
Structural Analysis Methods for the Roll-Out Solar Array Flight Experiment
The Roll-Out Solar Array (ROSA) flight experiment was launched to the International Space Station (ISS) on June 3rd, 2017. ROSA is an innovative, lightweight solar array with a flexible substrate that makes use of the stored strain energy in its composite structural members to provide deployment without the use of motors. This paper discusses the effort to model the structural dynamics of ROSA using finite element modeling. Two distinct and agnostic approaches were used by separate teams to assess the structural dynamics of the solar array prior to ground vibrational testing and flight testing. Results from each approach are compared to measured dynamics from accelerometers and photogrammetry data gathered on orbit. Advantages and disadvantages of each approach are discussed as are preliminary efforts to calibrate the models to the empirical data for the benefit of future modeling efforts on similar space structures
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