Electromagnetic wave energy conversion research

Known electromagnetic wave absorbing structures found in nature were first studied for clues of how one might later design large area man-made radiant-electric converters. This led to the study of the electro-optics of insect dielectric antennae. Insights were achieved into how these antennae probably operate in the infrared 7-14um range. EWEC theoretical models and relevant cases were concisely formulated and justified for metal and dielectric absorber materials. Finding the electromagnetic field solutions to these models is a problem not yet solved. A rough estimate of losses in metal, solid dielectric, and hollow dielectric waveguides indicates future radiant-electric EWEC research should aim toward dielectric materials for maximum conversion efficiency. It was also found that the absorber bandwidth is a theoretical limitation on radiant-electric conversion efficiency. Ideally, the absorbers' wavelength would be centered on the irradiating spectrum and have the same bandwith as the irradiating wave. The EWEC concept appears to have a valid scientific basis, but considerable more research is needed before it is thoroughly understood, especially for the complex randomly polarized, wide band, phase incoherent spectrum of the sun. Specific recommended research areas are identified

LIBRA: An inexpensive geodetic network densification system

A description is given of the Libra (Locations Interposed by Ranging Aircraft) system, by which geodesy and earth strain measurements can be performed rapidly and inexpensively to several hundred auxiliary points with respect to a few fundamental control points established by any other technique, such as radio interferometry or satellite ranging. This low-cost means of extending the accuracy of space age geodesy to local surveys provides speed and spatial resolution useful, for example, for earthquake hazards estimation. Libra may be combined with an existing system, Aries (Astronomical Radio Interferometric Earth Surveying) to provide a balanced system adequate to meet the geophysical needs, and applicable to conventional surveying. The basic hardware design was outlined and specifications were defined. Then need for network densification was described. The following activities required to implement the proposed Libra system are also described: hardware development, data reduction, tropospheric calibrations, schedule of development and estimated costs

Exploring what factors influence African American adolescent females to act violently towards each other

The purpose of this study is to explore the influential factors of African American adolescent and college-aged (13-20) females who engage in violent and aggressive behavior. The experience of these participants was elicited through self-developed, semi-structured interviews composed of questions that explored several possible contributing factors. Interviews were conducted with 12 females who self-identified as African American. The study explored themes of family dynamics, community violence exposure, identification with negative stereotypes and challenges with education and victimization. Major findings were that family dynamics and peer relationships were identified as major influential factors of the participant\u27s engagement in violent behavior. While there was a variation in emphasis and specificity in each participant\u27s discourse, majority of the participants shared similar responses. The limitations and implications of this study suggest that there\u27s a need for further study on this specific population and topic. This study represents each participant individually; giving the participants an opportunity to share their story. There still remains a need for further exploration

Community detection and role identification in directed networks: understanding the Twitter network of the care.data debate

With the rise of social media as an important channel for the debate and discussion of public affairs, online social networks such as Twitter have become important platforms for public information and engagement by policy makers. To communicate effectively through Twitter, policy makers need to understand how influence and interest propagate within its network of users. In this chapter we use graph-theoretic methods to analyse the Twitter debate surrounding NHS Englands controversial care.data scheme. Directionality is a crucial feature of the Twitter social graph - information flows from the followed to the followers - but is often ignored in social network analyses; our methods are based on the behaviour of dynamic processes on the network and can be applied naturally to directed networks. We uncover robust communities of users and show that these communities reflect how information flows through the Twitter network. We are also able to classify users by their differing roles in directing the flow of information through the network. Our methods and results will be useful to policy makers who would like to use Twitter effectively as a communication medium

Differential Very Long Baseline Interferometry (delta VLBI) spacecraft tracking system demonstration. Part 2: Data acquisition and processing

A set of experiments in the use of Differential Very Long Baseline Interferometry (delta VLBI) for spacecraft navigation were completed. Data using both Voyager spacecraft and a single quasar were acquired during the Jupiter encounter time period. The data were processed and analyzed to assess the navigation accuracy of delta VLBI. The data reduction and techniques for assessing data quality and consistency are discussed

A Comparison of Two Engineering Outreach Programs for Adolescents

There is continued growth and development of outreach programs designed to increase pre-college students’ awareness and understanding of engineering as a profession and as a career. These outreach programs vary in format and in the groups targeted for participation but maintain the same fundamental goal of increasing participant knowledge of engineering. Many of these outreach programs also maintain the implicit goal of increasing the participants\u27 knowledge and attitudes toward college. The additional resources and funding that are commonly allocated to support outreach programs frequently involve documenting accountability which motivates evaluation of program impact. Therefore, many outreach events include program evaluation to assess impact on the pre-college participants’ knowledge and perceptions of engineering, but they have not included the assessment of program impact on college attitudes. In this outreach program evaluation study, we examined the impact of two residential engineering outreach events on the participants\u27 engineering perceptions and attitudes and their college attitudes. Our results indicate a number of personal variables were predictors of college attitude, but we failed to expose any variables as indicators of engineering perceptions and attitudes. Analysis of the pre-post survey scores revealed a significant change in engineering perceptions and attitudes (p \u3c .01), but no significant change in college attitude (p =.07). We also exposed a differential impact by outreach event. Results, implications, limitations, and directions for future research are discussed

Mammy\u27s lullaby : a dreamy southern waltz / by Lee S. Roberts ; with words by J. Will Callahan.

https://digitalcommons.library.umaine.edu/mmb-vp/2077/thumbnail.jp

Ching Chong

https://digitalcommons.library.umaine.edu/mmb-vp/2852/thumbnail.jp

Diaphragm weakness and mechanical ventilation - what's the critical issue?

While animal studies indicate that controlled mechanical ventilation (MV) induces diaphragm weakness and myofiber atrophy, there are no data in humans that confirm MV per se produces diaphragm weakness. Whether or not diaphragm weakness results from MV, sepsis, corticosteroids, hyperglycemia, or a combination of these factors, however, is not the most important issue raised by the recent study from Hermans and colleagues. This study makes an important contribution by providing additional evidence that many critically ill patients have profound diaphragm weakness. If diaphragm weakness of this magnitude is present in most mechanically ventilated patients, a strong argument can be made that respiratory muscle weakness is a major contributor to respiratory failure