1,092 research outputs found

    Variable boundary II heat conduction

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    Computer program for solving both transient and steady-state heat transfer problems is presented. Specific applications of computer program are described. Formulation for individual nodes of solid medium for heat balance is presented. Diffusion equation is solved for all nodes simultaneously at finite increments of time

    The Battle for Higher Standards

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    In the aftermath of the federal mandates imposed through No Child Left Behind, the state-led effort to establish common math and English standards across states—known as the Common Core State Standards—seemed a welcome change in the approach to improving student achievement and success. However, the effort to ensure that students were ready for college or the workforce became the political target of those who distrust federal mandates and fear a nationalized education agenda bent on social engineering. The standards became intertwined with NSA spying, data mining, and federal grants for education with strings attached

    Embedded Sensors for Measuring Surface Regression

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    The development and evaluation of new hybrid and solid rocket motors requires accurate characterization of the propellant surface regression as a function of key operational parameters. These characteristics establish the propellant flow rate and are prime design drivers affecting the propulsion system geometry, size, and overall performance. There is a similar need for the development of advanced ablative materials, and the use of conventional ablatives exposed to new operational environments. The Miniature Surface Regression Sensor (MSRS) was developed to serve these applications. It is designed to be cast or embedded in the material of interest and regresses along with it. During this process, the resistance of the sensor is related to its instantaneous length, allowing the real-time thickness of the host material to be established. The time derivative of this data reveals the instantaneous surface regression rate. The MSRS could also be adapted to perform similar measurements for a variety of other host materials when it is desired to monitor thicknesses and/or regression rate for purposes of safety, operational control, or research. For example, the sensor could be used to monitor the thicknesses of brake linings or racecar tires and indicate when they need to be replaced. At the time of this reporting, over 200 of these sensors have been installed into a variety of host materials. An MSRS can be made in either of two configurations, denoted ladder and continuous (see Figure 1). A ladder MSRS includes two highly electrically conductive legs, across which narrow strips of electrically resistive material are placed at small increments of length. These strips resemble the rungs of a ladder and are electrically equivalent to many tiny resistors connected in parallel. A substrate material provides structural support for the legs and rungs. The instantaneous sensor resistance is read by an external signal conditioner via wires attached to the conductive legs on the non-eroding end of the sensor. The sensor signal can be transmitted from inside a high-pressure chamber to the ambient environment, using commercially available feedthrough connectors. Miniaturized internal recorders or wireless data transmission could also potentially be employed to eliminate the need for producing penetrations in the chamber case. The rungs are designed so that as each successive rung is eroded away, the resistance changes by an amount that yields a readily measurable signal larger than the background noise. (In addition, signal-conditioning techniques are used in processing the resistance readings to mitigate the effect of noise.) Hence, each discrete change of resistance serves to indicate the arrival of the regressing host material front at the known depth of the affected resistor rung. The average rate of regression between two adjacent resistors can be calculated simply as the distance between the resistors divided by the time interval between their resistance jumps. Advanced data reduction techniques have also been developed to establish the instantaneous surface position and regression rate when the regressing front is between rungs

    A Genre Of Collective Intelligence: Blogs As Intertextual, Reciprocal, And Pedagogical

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    This thesis investigates the rhetorical features of blogs that lend them dialogic strength as an online genre through the lens of Mikhail Bakhtin\u27s theories of speech genres, utterances, and dialogism. As a relatively new online genre, blogs stem from previous genres (in print and online as well as verbal), but their emergence as a popular form of expression in our current culture demands attention to how blogs also offer us different rhetorical opportunities to meet our changing social exigencies as online subjects in the 21st century. This thesis was inspired by questions about how blogs redefine the rhetorical situation to alter our textual roles as readers, writers, and respondents in the new generic circumstances we encounter--and reproduce--online. Applying the framework of Henry Jenkins\u27 Convergence Culture and Pierre Levy\u27s Collective Intelligence, this thesis analyzes how blogs enable us as online subjects to add our utterances to our textual collective intelligence, which benefits from our personal experience and the epistemic conversations of blogs as online texts. In addition, it is also an inquiry into how the rhetorical circumstances of blogs as textual sites of collective intelligence can create a reciprocal learning environment in the writing classroom. I ultimately examine blogs through the lenses of alternative pedagogy--informed by David Wallace and Helen Rothschild Ewald\u27s Mutuality in the Rhetoric and Composition Classroom and Xin Liu Gale\u27s Teachers, Discourses, and Authority in the Postmodern Composition Classroom--to suggest the potential consequences of a writing education that includes how we are currently writing--and being written by--our culture\u27s online generic practice of blogs

    Effects of Fluctuating Temperatures on Isowean Pigs

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    This study quantifies responses of isowean pigs (10 to 12 days of age, PIC breed) to potential in-transit temperature fluctuations for 54 h, followed by a 14-day growth period under thermoneutrality. The 54-h temperature regimens included a constant air temperature of 26.7°C (as control) and three cyclic air temperatures of 26.7 ± 2.8°C, 26.7 ± 5.6°C and 26.7 ± 8.3°C, all using woodshavings bedding atop rigid board insulation. The pigs received an average dosage of 0.91 kg/pig water replacement supply during the 54-h treatment period, and ad-libitum feeding and watering during the growth period. Pigs in all three treatments and the control had similar growth performance, physiological, and energetic responses during both treatment and growth periods. At the end of the treatment period, the pigs had elevated concentrations of hematocrit, plasma protein, blood urea nitrogen, sodium and chloride, but declined concentration of glucose (P \u3c 0.05). Potassium and bicarbonate levels remained relatively constant (P \u3e 0.05). Concentrations of the blood constituents returned to normal during the growth period. The results suggest that the isowean pigs respond well to air temperature fluctuations of up to ±8.3°C around the thermoneutral condition of 26.7°C air temperature coupled with woodshavings bedding

    TESSX: A Mission for Space Exploration with Tethers

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    Tethers offer significant potential for substantially increasing payload mass fraction, increasing spacecraft lifetime, enhancing long-term space travel, and enabling the understanding and development of gravity-dependent technologies required for Moon and Mars exploration. The development of the Tether Electrodynamic Spin-up and Survivability Experiment (TESSX) will support applications relevant to NASA's new exploration initiative, including: artificial gravity generation, formation flying, electrodynamic propulsion, momentum exchange, and multi-amp current collection and emission. Under the broad term TESSX, we are currently evaluating several different tether system configurations and operational modes. The initial results of this work are presented, including hardware development, orbital dynamics simulations, and electrodynamics design and analysis

    Stories at work : restorying narratives of new teachers\u27 identity learning in writing studies.

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    Rhetoric and composition has a long, robust history of studying how we train new writing teachers in our graduate/writing programs; yet we lack in-depth inquiries that foreground how new writing teachers learn. This dissertation traces five graduate students learning how to be and become writing teachers, using narrative as an object and means of analysis to study the tacitly internalized process of newcomer professional identity learning. In this project, I enact narrative as a feminist, interdisciplinary methodology to restory new writing teacher research narratives away from implicit deficit or explicit resistance and toward a more generative focus on newcomers’ motivated learning and complex experiences mediated by understandings of teaching, learning, and education that precede, exceed, and infuse the program training and academic literacy histories that our research has historically privileged. Drawing on research in writing studies, education, sociology, and psychology, this dissertation conducts a narrative inquiry into new writing teachers’ identity learning by analyzing stories of teaching and learning elicited from five new writing teachers during a year-long semi-structured, text-based interview study. Using the interplay of thematic and structural analysis of participants’ 248 stories and artifact analysis of participants’ teaching texts, I practice narrative inquiry as an explicitly feminist methodology to destabilize and interrogate what we think we know about new writing teachers’ identities and understandings of learning (as in Chapter Three), experiences and teaching troubles (as in Chapter Four), and motivated desires for the future (as in Chapter Five). I also rely on interdisciplinary theories of learning and identity to understand new teachers as complex people mediated and motivated over time in ways that academic writing/composition theories alone have not adequately illuminated. Ultimately, I argue that new teacher research in writing studies should employ more complex methodologies for studying new writing teachers’ identities as learned and storied over time; and that listening rhetorically to newcomers’ stories and for learning and meaning-making is one way to interrupt unproductive assumptions about newcomer deficit or resistance and to restory our research, administrative, and teaching practices to authorize and encourage more agentive positions from which newcomers (and we all) can learn to act

    Effects of Post-weaning Nutritional Conditions on Isowean Pigs

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    This study quantifies the responses of isowean pigs to post-weaning nutritional conditions as may be encountered during extended shipment. PIC breeding stock pigs at 8 to 12 days of age (3.5 to 4.0 kg body weight) were subjected to four nutritional regimens for 72 h. The pigs were then raised with ad libitum feeding for 14 days. Thermoneutral environments were used throughout the experiment. Pigs deprived of feed and water (i.e., Fast) had higher body weight loss (of 0.61 kg/pig or 17% of their initial body weight) as compared with pigs provided with feed and water supplement (0.39 kg/pig or 11% of their initial body weight) or water supplement only (0.43 kg/pig or 11.5% IBW) (P \u3c 0.05). All the treatments led to significant rise in blood urea nitrogen but fall in blood glucose (P \u3c 0.05). However, the glucose levels were much higher than the generally considered hypoglycemic level (75 mg/dL). All pigs showed a similar degree of dehydration, as evidenced by elevated hematocrit and blood electrolyte concentrations (P \u3c 0.05). The physiological responses returned to normal during the 14-day growth period and were similar for all the pigs. The results suggest that isowean pigs (PIC genetic line) responded well to post-weaning nutritional conditions typically encountered during extended shipments. Supply of bacteria-resistant water supplement such as Aqua-Jel seemed beneficial in reducing stress and may be considered for extended commercial shipment. However, in-transit supply of feed added little benefit to the pigs and thus may be omitted. This omission has special implications for international shipments because certain countries prohibit inclusion of feed in shipment. The energetics data of this study may be used to design and operate ventilation systems in transportation and production facilities for the isowean pigs
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