Wake Vortex Encounter Research

The National Aeronautics and Space Administration (NASA) is conducting research to improve airport capacity by reducing the separation distance between aircraft. The limiting factor in reducing separation distances and improving airport capacity is the wake vortex hazard. The ability to accurately model wake vortices and predict the outcome of a vortex encounter is critical in developing a system to safely improve airport capacity. This is the focus of the wake vortex research being done at NASA Langley Research Center (LaRC). This paper will concentrate on two topics. The first topic is the control system developed for the Boeing 737 freeflight model in support of vortex encounter tests to be conducted in the 30- by 60- foot tunnel at NASA Langley Research Center later this year. The second topic discussed is the limited degree of freedom (DOF) trajectory generation study that is being conducted to determine the relative severity of a multitude of paths through a wake vortex

Flatness optimization of micro-injection moulded parts: The case of a PMMA microfluidic component

Micro-injection moulding (µ-IM) has attracted a lot of interest because of its potential for the production of low-cost, miniaturized parts in high-volume. Applications of this technology are, amongst others, microfluidic components for lab-on-a-chip devices and micro-optical components. In both cases, the control of the part flatness is a key aspect to maintaining the component's functionality. The objective of this work is to determine the factors affecting the flatness of a polymer part manufactured by µ-IM and to control the manufacturing process with the aim of minimizing the in-process part deformation. As a case study, a PMMA microfluidic substrate with overall dimensions of 10 mm diameter and 1 mm thickness was investigated by designing a µ-IM experiment having flatness as the experimental response. The part flatness was measured using a micro-coordinate measuring machine. Finite elements analysis was also carried out to study the optimal ejection pin configuration. The results of this work show that the control of the µ-IM process conditions can improve the flatness of the polymer part up to about 15 µm. Part flatness as low as 4 µm can be achieved by modifying the design of the ejection system according to suggested guideline

Integrating Information Literacy Instruction in an Upper-Division Writing-Intensive Class

Writing-intensive courses are a required component of undergraduate education at the University of South Alabama, but often the courses are designed to test students’ writing skills, rather than to teach the research and writing process. In the fall of 2008, an instruction librarian and an assistant professor in political science collaborated to redesign one writing intensive course, Public Administration (PSC 401), in an attempt to address this dilemma. This project was born out of frustration – frustration on the part of the professor about the generally poor quality of writing and research skills by students in the course the previous year, and frustration on the part of the librarian at a lack of opportunities for integrating information literacy instruction (beyond one-shot bibliographic instruction sessions) into the curriculum. The project was also born out of optimism that a new approach could make a difference in improving students’ abilities in terms of researching and writing papers

Two-Dimensional Simulation of Left-Handed Metamaterial Flat Lens Using Remcon XFDTD

Remcom's XFDTD software was used to model the properties of a two-dimensional left-handed metamaterial (LHM) flat lens. The focusing capability and attenuation of the material were examined. The results showed strong agreement with experimental results and theoretical predictions of focusing effects and focal length. The inherent attenuation in the model corresponds well with the experimental results and implies that the code does a reasonably accurate job of modeling the actual metamaterial

An associated partial skeleton of Jainosaurus cf. septentrionalis (Dinosauria: Sauropoda) from the Late Cretaceous of Chhota Simla, Central India

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86940/1/j.1475-4983.2011.01087.x.pd

A temnospondyl trackway from the early mesozoic of Western gondwana and its implications for Basal tetrapod locomotion

BACKGROUND: Temnospondyls are one of the earliest radiations of limbed vertebrates. Skeletal remains of more than 190 genera have been identified from late Paleozoic and early Mesozoic rocks. Paleozoic temnospondyls comprise mainly small to medium sized forms of diverse habits ranging from fully aquatic to fully terrestrial. Accordingly, their ichnological record includes tracks described from many Laurasian localities. Mesozoic temnospondyls, in contrast, include mostly medium to large aquatic or semi-aquatic forms. Exceedingly few fossil tracks or trackways have been attributed to Mesozoic temnospondyls, and as a consequence very little is known of their locomotor capabilities on land. METHODOLOGY/PRINCIPAL FINDINGS: We report a ca. 200 Ma trackway, Episcopopus ventrosus , from Lesotho, southern Africa that was made by a 3.5 m-long animal. This relatively long trackway records the trackmaker dragging its body along a wet substrate using only the tips of its digits, which in the manus left characteristic drag marks. Based on detailed mapping, casting, and laser scanning of the best-preserved part of the trackway, we identified synapomorphies (e.g., tetradactyl manus, pentadactyl pes) and symplesiomorphies (e.g., absence of claws) in the Episcopopus trackway that indicate a temnospondyl trackmaker. Conclusions/Significance Our analysis shows that the Episcopopus trackmaker progressed with a sprawling posture, using a lateral-sequence walk. Its forelimbs were the major propulsive elements and there was little lateral bending of the trunk. We suggest this locomotor style, which differs dramatically from the hindlimb-driven locomotion of salamanders and other extant terrestrial tetrapods can be explained by the forwardly shifted center of mass resulting from the relatively large heads and heavily pectoral girdles of temnospondyls

When Disclosure is Involuntary: Empowering Users with Control to Reduce Concerns

Modern organizations must carefully balance the practice of gathering large amounts of valuable data from individuals with the associated ethical considerations and potential negative public image inherent in breaches of privacy. As it becomes increasingly commonplace for many types of information to be collected without individuals\u27 knowledge or consent, managers and researchers alike can benefit from understanding how individuals react to such involuntary disclosures, and how these reactions can impact evaluations of the data-collecting organizations. This research develops and empirically tests a theoretical model that shows how empowering individuals with a sense of control over their personal information can help mitigate privacy concerns following an invasion of privacy. Using a controlled experiment with 94 participants, we show that increasing control can reduce privacy concerns and significantly influence individuals\u27 attitudes toward the organization that has committed a privacy invasion. We discuss theoretical and practical implications of our work

Obesity: transition from adolescence to adulthood and feedback partial gmm logistic model with time-dependent covariates

Background: The aim of this study is to investigate the impact of certain covariates on obesity. More importantly, we seek to determine the feedback of obesity on depression, and physical activity as they transition from adolescence to young adulthood. Methods: Using 15 years of nationally representative data from 6560 adolescents (Add health data), we estimate feedback and associations between depression, and activity scale on obesity while we adjusted for gender, age, race/ethnicity, socioeconomic status through a GMM logistic regression model with time-dependent covariates. Results: Activity (p<0.001) and depression (p<0.001) have significant impact on Obesity. In early years, alcohol had no impact (p=0.895 and p=0.476) on obesity but in later years it did (p<0.001). In the early years, television hours had an impact but as they got older, it did not. Conclusion: Our findings suggest that public health researchers can target obesity simultaneously with depression, and activity scale. These findings contribute new insights into the feedback of obesity on depression, and activity. This unique model allows segments of associations to be addressed rather than assuming all associations remain the same over 15 years.&nbsp

Predicting functional outcomes after stroke: An observational study of acute single-channel EEG

Background: Early and objective prediction of functional outcome after stroke is an important issue in rehabilitation. Electroencephalography (EEG) has long been utilized to describe and monitor brain function following neuro-trauma, and technological advances have improved usability in the acute setting. However, skepticism persists whether EEG can provide the same prognostic value as neurological examination. Objective: The current cohort study examined the relationship between acute single-channel EEG and functional outcomes after stroke. Methods: Resting-state EEG recorded at a single left pre-frontal EEG channel (FP1) was obtained from 16 adults within 72 h of first stroke. At 30 and 90 days, measures of disability (modified Rankin Scale; mRS) and involvement in daily activities (modified Barthel Index; mBI) were obtained. Acute EEG measures were correlated with functional outcomes and compared to an early neurological examination of stroke severity using the National Institute of Health Stroke Scale (NIHSS). Classification of good outcomes (mRS ≤1 or mBI ≥95) was also examined using Receiver Operator Curve analyses. Results: One-third to one-half of participants experienced incomplete post-stroke recovery, depending on the time point and measure. Functional outcomes correlated with acute theta values (rs 0.45–0.60), with the strength of associations equivalent to previously reported values obtained from conventional multi-channel systems. Acute theta values ≥0.25 were associated with good outcomes, with positive (67-83%) and negative predictive values (70-90%) comparable to those obtained using the NIHSS. Conclusions: Acute, single-channel EEG can provide unique, non-overlapping clinical information, which may facilitate objective prediction of functional outcome after stroke