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Enhancement of Light Emission from Metal Nanoparticles Embedded Graphene Oxide

Description: A fully oxidized state of graphene behaves as a pure insulating while a pristine graphene behaves as a pure conducting. The in-between oxide state in graphene which is the controlled state of oxide behaves as a semiconducting. This is the key condition for tuning optical band gap for the better light emitting property. The controlling method of oxide in graphene structure is known as reduction which is the mixed state of sp2 and sp3 hybrid state in graphene structure. sp2 hybridized domains correspond to pure carbon-carbon bond i.e. pristine graphene while sp3 hybridized domains correspond to the oxide bond with carbon i.e. defect in graphene structure. This is the uniqueness of the graphene-base material. Graphene is a gapless material i.e. having no bandgap energy and this property prevents it from switching device applications and also from the optoelectronic devices applications. The main challenge for this material is to tune as a semiconducting which can open the optical characteristics and emit light of desired color. There may be several possibilities for the modification of graphene-base material that can tune a band gap. One way is to find semiconducting property by doping the defects into pristine graphene structure. Other way is oxides functional groups in graphene structure behaves as defects. The physical properties of graphene depend on the amount of oxides present in graphene structure. So if there are more oxides in graphene structure then this material behaves as a insulating. By any means if it can be reduced then oxides amount to achieve specific proportion of sp2 and sp3 that can emit light of desired color. Further, after achieving light emission from graphene base material, there is more possibility for the study of non-linear optical property. In this work, plasmonic effect in graphene oxide has been focused. Mainly there are two ...
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Date: May 2016
Creator: Karna, Sanjay K

The enhancement of machine translation for low-density languages using Web-gathered parallel texts.

Description: The majority of the world's languages are poorly represented in informational media like radio, television, newspapers, and the Internet. Translation into and out of these languages may offer a way for speakers of these languages to interact with the wider world, but current statistical machine translation models are only effective with a large corpus of parallel texts - texts in two languages that are translations of one another - which most languages lack. This thesis describes the Babylon project which attempts to alleviate this shortage by supplementing existing parallel texts with texts gathered automatically from the Web -- specifically targeting pages that contain text in a pair of languages. Results indicate that parallel texts gathered from the Web can be effectively used as a source of training data for machine translation and can significantly improve the translation quality for text in a similar domain. However, the small quantity of high-quality low-density language parallel texts on the Web remains a significant obstacle.
Date: December 2007
Creator: Mohler, Michael Augustine Gaylord

Enhancement of spatial ability in girls in a single-sex environment through spatial experience and the impact on information seeking.

Description: The test scores of spatial ability for women lag behind those of men in many spatial tests. On the Mental Rotations Test (MRT), a significant gender gap has existed for over 20 years and continues to exist. High spatial ability has been linked to efficiencies in typical computing tasks including Web and database searching, text editing, and computer programming. The relationships between the components of visuospatial ability and performance are complex. However, research strongly indicates that a connection exists, and further research is necessary to determine the interactions between the variables of environment, genetics, and spatial training. Spatial experience can enhance spatial skills. However, to what extent spatial skills can be enhanced in female adolescents through a spatial curriculum to reduce the gap in scores has not been fully researched, nor has the impact of spatial skill on information seeking. This research project investigated spatial skill in adolescent females by examining (1) the extent to which the intervention of teaching a spatial curriculum in a single-sex setting could improve mental rotation test scores, and (2) the impact of spatial skills on an information seeking task in a single-sex setting. The extent to which a spatial visualization curriculum can improve MRT scores from a pretest to a posttest for girls was the first factor examined using a spatial visualization curriculum. The information seeking task used 4 tasks from a doctoral study and utilized the scholarly journal database JSTOR® (JSTOR, Ann Arbor, MI, www.jstor.org).
Date: December 2008
Creator: Swarlis, Linda L.

Enhancements of Mechanical, Thermal Stability, and Tribological Properties by Addition of Functionalized Reduced Graphene Oxide in Epoxy

Description: The effects of octadecylamine-functionalized reduced graphene oxide (FRGO) on the frictional and wear properties of diglycidylether of bisphenol-A (DGEBA) epoxy are studied using a pin-on-disk tribometer. It was observed that the addition of FRGO significantly improves the tribological, mechanical, and thermal properties of epoxy matrix. Graphene oxide (GO) was functionalized with octadecylamine (ODA), and then reduction of oxygen-containing functional groups was carried out using hydrazine monohydrate. The Raman and x-ray photoelectron spectroscopy studies confirm significant reduction in oxygen-containing functional groups and formation of ODA functionalized reduced GO. The nanocomposites are prepared by adding 0.1, 0.2, 0.5 and 1.0 wt % of FRGO to the epoxy. The addition of FRGO increases by more than an order of magnitude the sliding distance during which the dynamic friction is ≤ 0.1. After this distance, the friction sharply increases to the range of 0.4 - 0.5. We explain the increase in sliding distance during which the friction is low by formation of a transfer film from the nanocomposite to the counterface. The wear rates in the low and high friction regimes are approximately 1.5 x 10-4 mm3/N·m and 5.5 x 10-4 mm3/N·m, respectively. The nanocomposites exhibit a 74 % increase in Young’s modulus with 0.5 wt. % of FRGO, and an increase in glass transition and thermal degradation temperatures.
Date: August 2014
Creator: Shah, Rakesh K.

Enhancing skill maintenance through relapse prevention strategies: a comparison of two models.

Description: In a quasi-experimental field study, two posttraining interventions composed of relapse prevention (RP) strategies were compared and tested for the effects on participant transfer outcomes. Participant retention of training content, skill maintenance, use of relapse prevention strategies, and self-efficacy served as the dependent variables. Self-efficacy was also tested as a mediator between the experimental treatment levels and both participant skill maintenance and participant use of RP strategies. Participants (n = 39) included managers, directors, and supervisors from various departments within a multi-national telecommunications organization located in a large southern city. After participating in a four-hour leadership development training, two of the three groups participated in a 30-40 minute training where they received one of two RP interventions. One intervention included the steps of (1) identifying potential obstacles to positive training transfer, (2) predicting the first lapse to pretraining behavior, and (3) applying relevant coping strategies to thwart a lapse. The alternative RP intervention included the same steps in addition to a goal setting step. Descriminant descriptive analysis was used to test for group differences across the response variables and to identify on which variables the groups differed. Three separate regression equations were used to test for the mediating relationship of self-efficacy between the RP treatment levels and participant skill maintenance and participant use of RP strategies. Results indicated minimal, but non-statistically significant results between treatment levels and each of the response variables. Self-efficacy was not found to mediate the relationship between RP treatment level and participant skill maintenance or participant use of RP strategies, but did function as a strong predictor of both variables. Suggestions for future research include using additional motivational and efficacy variables to better explore group differences and including efficacy-inducing methods both in training design and as part of a transfer intervention to enhance training transfer. Further, ...
Date: May 2004
Creator: Hutchins, Holly M.

Enhancing User Search Experience in Digital Libraries with Rotated Latent Semantic Indexing

Description: This study investigates a semi-automatic method for creation of topical labels representing the topical concepts in information objects. The method is called rotated latent semantic indexing (rLSI). rLSI has found application in text mining but has not been used for topical labels generation in digital libraries (DLs). The present study proposes a theoretical model and an evaluation framework which are based on the LSA theory of meaning and investigates rLSI in a DL environment. The proposed evaluation framework for rLSI topical labels is focused on human-information search behavior and satisfaction measures. The experimental systems that utilize those topical labels were built for the purposes of evaluating user satisfaction with the search process. A new instrument was developed for this study and the experiment showed high reliability of the measurement scales and confirmed the construct validity. Data was collected through the information search tasks performed by 122 participants using two experimental systems. A quantitative method of analysis, partial least squares structural equation modeling (PLS-SEM), was used to test a set of research hypotheses and to answer research questions. The results showed a not significant, indirect effect of topical label type on both guidance and satisfaction. The conclusion of the study is that topical labels generated using rLSI provide the same levels of alignment, guidance, and satisfaction with the search process as topical labels created by the professional indexers using best practices.
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Date: August 2015
Creator: Polyakov, Serhiy

Enigmatic Realms

Description: The use of copper in my work has opened up an entirely new conceptual and esthetic world. I have expanded my vocabulary of visual imagery based on the nature of how copper reacts with fire. The organic beauty harmonizes so gracefully with the manufactured material. This new material has certainly opened up a refreshing platform on which to further develop my ideas.
Date: December 2003
Creator: Malik, Irum

Enkephalin Metabolism in Exercise Stress

Description: Investigators have suggested that opiate peptide hormones released during exercise stress may play an important role in athletic performance or perceived effort. Their enzymatic inactivation in the periphery is of considerable interest since the opiate peptides may be regulated by enkephalin hydrolyzing enzyme (EHA). In this study, the relationship between maximal aerobic capacity (VO_2max) and EHA activity was examined in two distinct fitness groups. When the metabolic capacity was evaluated in whole blood, the unfit subjects metabolized the peptides significantly faster than their fit counterparts. Since the total enzyme activity of the two groups is similar, the difference in metabolism must result from circulating factors in the trained athletes, which slow the rate of peptide inactivation.
Date: December 1984
Creator: Jaskowski, Margaret Anne

The Enlightenment and the Englishwoman

Description: The present study investigates the failure of the Enlightenment to liberate Englishwomen from the prejudices society and law imposed upon them. Classifying social classes by lifestyle, the roles of noble, middleclass, and criminal women, as well as the attitudes of contemporary writers of both sexes, are analyzed. This investigation concludes that social mores limited noblewomen to ornamental roles and condemned them to exist in luxurious boredom; forced middle-class women to emulate shining domestic images which contrasted sharply with the reality of their lives; subjected women of desperate circumstances to a criminal code rendered erratic and inconsistent by contemporary attitudes, and impelled the Enlightenment to invent new defenses for old attitudes toward women.
Date: December 1983
Creator: Morris, Jan Jenkins

The Enlightenment Legacy of David Hume

Description: Although many historians assert the unity of the Enlightenment, their histories essentially belie this notion. Consequently, Enlightenment history is confused and meaningless, urging the reader to believe that diversity is similarity and faction is unity. Fundamental among the common denominators of these various interpretations, however, are the scientific method and empirical observation, as introduced by Newton. These, historians acclaim as the turning point when mankind escaped the ignorance of superstition and the oppression of the church, and embarked upon the modern secular age. The Enlightenment, however, founders immediately upon its own standards of empiricism and demonstrable philosophical tenets, with the exception of David Hume. As the most consistent and fearless empiricist of the era, Hume's is by far the most "legitimate" philosophy of the Enlightenment, but it starkly contrasts the rhetoric and ideology of the philosophe community, and, therefore, defies attempts by historians to incorporate it into the traditional Enlightenment picture. Hume, then, exposes the Enlightenment dilemma: either the Enlightenment is not empirical, but rather the new Age of Faith Carl Becker proclaimed it, or Enlightenment philosophy is that of Hume. This study presents the historical characterization of major Enlightenment themes, such as method, reason, religion, morality, and politics, then juxtaposes this picture with the particulars (data) that contradict or seriously qualify it. As a result, much superficial analysis, wishful thinking, even proselytizing is demonstrated in the traditional Enlightenment characterization, especially with regard to the widely heralded liberal and progressive legacy of the era. In contrast, Hume's conclusions, based on the method of Newton-the essence of "enlightened" philosophy, are presented, revealing the authoritarian character (and legacy) of the Enlightenment as well as the utility and relevance of its method when honestly and rigorously applied. Through David Hume, the twentieth century can truly acquire what the Enlightenment promised—an understanding of human ...
Date: December 1989
Creator: Jenkins, Joan (Joan Elizabeth)

Enrique Pérez Eschrich

Description: No extensive study exists that covers the foundation of the dramatic works of Enrique Pérez Escrich, therefore we believe it will be a positive use of our efforts in this thesis to examine this aspect of his literary personality. We will divide his works between dramas and comedies, dedicating a chapter to each.
Date: January 1967
Creator: Tomassini, Juan B.

Enrollment Management in Higher Education: From Theory to Practice

Description: This study investigated enrollment management practices found in higher education. The research identified enrollment management and retention practices described in the higher education literature. These suggested practices were incorporated into a sixty-six question survey that was distributed to a random sample of colleges and universities taken from the 1999 US News and World Report of college rankings. The survey data were used to identify which of the suggested enrollment management practices were of greatest utility. First, the sixty-six items were grouped into 14 categories of enrollment management strategies. Second, the institutional responses for each category were averaged and then correlated with each institution's graduation rate. Finally, each institution's "yes" responses for the entire survey were totaled and correlated with each institution's graduation rate. This study developed a list of the 26 most frequently used enrollment management practices in higher education, and as well, identified the 10 least used enrollment management practices. Given the results of this study graduation rate is not a sufficient criterion to assess enrollment management practices at a college or university. Enrollment management strategies contribute to many institutional and student outcomes; thus, multiple indicators are required to accurately evaluate enrollment management practices.
Date: August 2000
Creator: Clark, V. Allen

Ensuring Authenticity and Integrity of Critical Information Using XML Digital Signatures

Description: It has been noticed in the past five years that the Internet use has been troubled by the lack of sufficient security and a legal framework to enable electronic commerce to flourish. Despite these shortcomings, governments, businesses and individuals are using the Internet more often as an inexpensive and ubiquitous means to disseminate and obtain information, goods and services. The Internet is insecure -- potentially millions of people have access, and "hackers" can intercept anything traveling over the wire. There is no way to make it a secure environment; it is, after all, a public network, hence the availability and affordability. In order for it to serve our purposes as a vehicle for legally binding transactions, efforts must be directed at securing the message itself, as opposed to the transport mechanism. Digital signatures have been evolved in the recent years as the best tool for ensuring the authenticity and integrity of critical information in the so called "paperless office". A model using XML digital signatures is developed and the level of security provided by this model in the real world scenario is outlined.
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Date: December 2002
Creator: Korivi, Arjun

Entering the Circle: The Only Viable Hermeneutic for a Biblical Response to Ecocrisis

Description: A paradox exists in attempting to resolve ecocrisis: awareness of ecological concerns is growing, but the crisis continues to escalate. John Firor, a well-known scientist, suggests that to resolve the paradox and hence ecocrisis, we need an alternative definition of "human beingness"--that is, a human ontology.
Date: August 1997
Creator: Veak, Tyler J. (Tyler James)

Enterprise Social Software: an Empirical Assessment of Knowledge Sharing in the Workplace

Description: Social software has become pervasive including technologies such as blogs, wikis, and social networking sites. Interactive Web 2.0 technology is distinguished from earlier Internet channels, with content provided not only from the website host, but also and most importantly, user-generated content. These social technologies are increasingly entering the enterprise, involving complex social and psychological aspects as well as an understanding of traditional technology acceptance factors. Organizations trying to reap potential benefits of enterprise social software (ESS) must successfully implement and maintain ESS tools. This research develops a framework for assessing knowledge sharing based on reciprocal determinism theory and augmented with technology acceptance, sociological, and psychological factors. Semi-structured interviews with IT professionals, followed by a written survey of employees using ESS are used to collect data. The hermeneutic circle methodology is used to analyze the interview transcripts and structural equation modeling is used to analyze the survey data. Results show technological advantage has no significant effect on the intention to share knowledge, but community cohesiveness and individual willingness significantly affect knowledge sharing intention and behavior. The study offers a synthesized model of variables affecting knowledge sharing as well as a better understanding of best practices for organizations to consider when implementing and maintaining ESS tools for employee knowledge sharing and collaboration.
Date: August 2013
Creator: Harden, Gina

An entropic approach to the analysis of time series.

Description: Statistical analysis of time series. With compelling arguments we show that the Diffusion Entropy Analysis (DEA) is the only method of the literature of the Science of Complexity that correctly determines the scaling hidden within a time series reflecting a Complex Process. The time series is thought of as a source of fluctuations, and the DEA is based on the Shannon entropy of the diffusion process generated by these fluctuations. All traditional methods of scaling analysis, instead, are based on the variance of this diffusion process. The variance methods detect the real scaling only if the Gaussian assumption holds true. We call H the scaling exponent detected by the variance methods and d the real scaling exponent. If the time series is characterized by Fractional Brownian Motion, we have H¹d and the scaling can be safely determined, in this case, by using the variance methods. If, on the contrary, the time series is characterized, for example, by Lévy statistics, H ¹ d and the variance methods cannot be used to detect the true scaling. Lévy walk yields the relation d=1/(3-2H). In the case of Lévy flights, the variance diverges and the exponent H cannot be determined, whereas the scaling d exists and can be established by using the DEA. Therefore, only the joint use of two different scaling analysis methods, the variance scaling analysis and the DEA, can assess the real nature, Gauss or Lévy or something else, of a time series. Moreover, the DEA determines the information content, under the form of Shannon entropy, or of any other convenient entopic indicator, at each time step of the process that, given a sufficiently large number of data, is expected to become diffusion with scaling. This makes it possible to study the regime of transition from dynamics to thermodynamics, non-stationary regimes, ...
Date: December 2001
Creator: Scafetta, Nicola

Environmental Determinants and Choice of Project Evaluation Techniques in US and UK Firms

Description: The purpose of this dissertation is to develop a theory that helps explain the conditions under which firms select certain project evaluation techniques. This study uses contingency theory to analyze the impact of environmental uncertainty on the choice of project evaluation techniques. In addition to a direct measure of uncertainty, several dimensions of uncertainty are included in this study. These dimensions of uncertainty include control structure, method of financing, foreign assets, method of growth, and product domination. This study also analyzes the use of project evaluation, management science and risk management techniques in US firms over time and in UK firms over time in order to compare to prior research. A comparison of firms in the two countries are also provided. The primary method of data collection was a survey instrument. Data were also collected from annual reports and various other public sources. The variables that appear significant in the choice of project evaluation technique in US firms are environmental uncertainty, control structure, method of financing, foreign assets, and product domination. The variable that appear significant in the choice of project evaluation technique in UK firms is method of financing. US firms favor discounted cash flow techniques although this study detected a slight decrease over time. UK firms continue to use non-discounted cash flow techniques, although the use of discounted cash flow techniques is widespread. There are significant differences between US and UK firms. US firms tend to use discounted cash flow techniques to a greater extent than UK firms. This research makes a significant contribution in attempting to develop a theory explaining the use of project evaluation techniques in firms in the US and UK. In addition, several other developments relating to project evaluation, management science and risk management are discussed. The results of this study can be used ...
Date: May 1996
Creator: Smolarski, Jan M. (Jan Mietek)

Environmental Ethics from the Periphery: José Lutzenberger and the Philosophical Analysis of an Unecological Economics

Description: This dissertation provides a philosophical analysis about the influence colonialism had over capitalism's current configuration and how their intricate interplay impacts both the social and the ecological spheres, in both central and peripheral countries. Such analysis draws from the work of José Lutzenberger, a Brazilian environmentalist. The current capitalist economic system tends to disregard the environment, since it would be greatly affected by negative externalities. A negative externality is an economic activity that imposes a negative effect on an unrelated third party. Many negative externalities are related to the environmental consequences of production and consumption. In addition, this dissertation explores the fact that an ecological crisis is also a social crisis. A genealogical and existential thread going from Brazil's early days as one of Portugal's colonies to the present is drawn, showing how colonialism helped to create the foundations and the conditions for the current exploitative capitalist system, in Brazil and elsewhere. To change this situation, the environment should not be entrusted to private interests but to an institution responsible for the good of society as a whole. Genuinely green economies are more prone to appear on the periphery, but only if global economic justice is achieved first.
Date: August 2016
Creator: Valenti Possamai, Fabio