Improved methodology to evaluate fracture properties of warm-mix asphalt using overlay test

This study developed a reliable and repeatable methodology to evaluate the fracture properties of asphalt mixtures with an overlay test (OT). In the proposed methodology, first, a two-step OT protocol was used to characterize the undamaged and damaged behaviors of asphalt mixtures. Second, a new methodology combining the mechanical analysis of viscoelastic force equilibrium in the OT specimen and finite element simulations was used to determine the undamaged properties and crack growth function of asphalt mixtures. Third, a modified Paris's law replacing the stress intensity factor by the pseudo J-integral was employed to characterize the fracture behavior of asphalt mixtures. Theoretical equations were derived to calculate the parameters A and n (defined as the fracture properties) in the modified Paris's law. The study used a detailed example to calculate A and n from the OT data. The proposed methodology was successfully applied to evaluate the impact of warm-mix asphalt (WMA) technologies on fracture properties. The results of the tested specimens showed that Evotherm WMA technology slightly improved the cracking resistance of asphalt mixtures, while foaming WMA technology provided comparable fracture properties. In addition, the study found that A decreased with the increase in n in general. A linear relationship between 2log(A) and n was established.

Munkavállalói preferenciák az egyetemi hallgatók körében = Employees' preferences according to graduates and undergraduates

Napjaink munkaerőpiaci tendenciái következtében egyre több figyelem irányul az atipikus munkavégzésre. Az atipikus munkavégzésben rejlő lehetőségeket a munkavállalók oldaláról vizsgáltuk. Ennek érdekében egy kétfázisú kutatássorozatot hajtottuk végre a Budapesti Corvinus Egyetem hallgatói körében. A felmérés rámutatott arra, hogy az egyetemi hallgatók már az egyetemi tanulmányaik alatt is potenciális munkaerőt jelentenek. Foglalkoztatásuk során a legfontosabb tényező a rugalmas, tanulmányokkal összeegyeztethető munkavégzés. A második kutatás fő célja a teljes életcikluson keresztüli munkavállalói preferenciák feltárása volt. A hallgatók által a két leginkább előnybe részesített munkavállalási forma a napi nyolcórás munkaviszony rugalmas munkaidőben és a saját vállalkozás indítása. A hallgatók elsősorban magas jövedelmet, ezt követően stabil, biztos jövedelmet, fejlődési lehetőséget, és a munka és magánélet egyensúlyát várják el munkahelyüktől. A tanulmány rámutat az egyes alcsoportok különbségeire, illetve kiindulópontot jelenthet további kutatásokhoz. _____ More and more attention is paid to atypical work due to workplace trends. Increasing opportunities deriving from atypical work have been investigated from employees’ viewpoint in this paper. We conducted a two-step survey amongst graduates and undergraduates of Corvinus University of Budapest. The survey pointed out that undergraduates are potential workers as well, and the most important factor for them was the flexible form of work. The second survey aimed to explore employees’ preferences through a whole lifetime period. The two most popular forms of work were flexible full-time jobs and starting their own enterprise. Students prefer high salaries, a stable and secure income, opportunities for development and work-life balance. The surveys pointed out some differences between subgroups and their conclusions could be a starting point for future research.

Participation in a positive youth development program and multi -problem alternative high school students' transformative goals: An investigation of the theoretical and methodological utility and validity of the Transformative Goal Attainment (TGAS)

There is a growing body of literature that provides evidence for the efficacy of positive youth development programs in general and preliminary empirical support for the efficacy of the Changing Lives Program (CLP) in particular. This dissertation sought to extend previous efforts to develop and preliminarily examine the Transformative Goal Attainment Scale (TGAS) as a measure of participant empowerment in the promotion of positive development. Consistent with recent advances in the use of qualitative research methods, this dissertation sought to further investigate the utility of Relational Data Analysis (RDA) for providing categorizations of qualitative open-ended response data. In particular, a qualitative index of Transformative Goals, TG, was developed to complement the previously developed quantitative index of Transformative Goal Attainment (TGA), and RDA procedures for calculating reliability and content validity were refined. Second, as a Stage I pilot/feasibility study this study preliminarily examined the potentially mediating role of empowerment, as indexed by the TGAS, in the promotion of positive development. ^ Fifty-seven participants took part in this study, forty CLP intervention participants and seventeen control condition participants. All 57 participants were administered the study's measures just prior to and just following the fall 2003 semester. This study thus used a short-term longitudinal quasi-experimental research design with a comparison control group. ^ RDA procedures were refined and applied to the categorization of open-ended response data regarding participants' transformative goals (TG) and future possible selves (PSQ-QE). These analyses revealed relatively strong, indirect evidence for the construct validity of the categories as well as their theoretically meaningful structural organization, thereby providing sufficient support for the utility of RDA procedures in the categorization of qualitative open-ended response data. ^ In addition, transformative goals (TG) and future possible selves (PSQ-QE), and the quantitative index of perceived goal attainment (TGA) were evaluated as potential mediators of positive development by testing their relationships to other indices of positive intervention outcome within a four-step method involving both analysis of variance (ANOVA and RMANOVAs) and regression analysis. Though more limited in scope than the efforts at the development and refinement of the measures of these mediators, the results were also promising. ^

An investigation into the lived experiences of racism among African -American nurses

The purpose of this study was to investigate the lived experience of racism among African-American nurses. Utilizing a qualitative phenomenological approach, data were collected by interviewing 10 African-American nurses currently practicing in Dade county. The interviews were tape recorded and transcribed verbatim. Data were analyzed using the seven step method of Colaizzi (1978). The findings of this study indicate that racism encompasses attitudes and beliefs which generate behaviors reflecting ethnocentric ideations. The process of racism creates glass ceilings that hinder the career advancement of African-American nurses. Internalizing these experiences of racism engenders feelings of betrayal and erodes unity and cohesion within the group. This study points out the need to openly confront racism in the nursing profession, from the classroom to the workplace.

Database of the GLAMAP project

A uniform chronology for foraminifera-based sea surface temperature records has been established in more than 120 sediment cores obtained from the equatorial and eastern Atlantic up to the Arctic Ocean. The chronostratigraphy of the last 30,000 years is mainly based on published d18O records and 14C ages from accelerator mass spectrometry, converted into calendar-year ages. The high-precision age control provides the database necessary for the uniform reconstruction of the climate interval of the Last Glacial Maximum within the GLAMAP-2000 project.

Shifts of the psychometric function: distinguishing bias from perceptual effects.

Morgan, Dillenburger, Raphael, and Solomon have shown that observers can use different response strategies when unsure of their answer, and, thus, they can voluntarily shift the location of the psychometric function estimated with the method of single stimuli (MSS; sometimes also referred to as the single-interval, two-alternative method). They wondered whether MSS could distinguish response bias from a true perceptual effect that would also shift the location of the psychometric function. We demonstrate theoretically that the inability to distinguish response bias from perceptual effects is an inherent shortcoming of MSS, although a three-response format including also an "undecided" response option may solve the problem under restrictive assumptions whose validity cannot be tested with MSS data. We also show that a proper two-alternative forced-choice (2AFC) task with the three-response format is free of all these problems so that bias and perceptual effects can easily be separated out. The use of a three-response 2AFC format is essential to eliminate a confound (response bias) in studies of perceptual effects and, hence, to eliminate a threat to the internal validity of research in this area.

Nitric-acid Hydrolysis of Miscanthus giganteus to Sugars Fermented to Bioethanol

Peer reviewed

Epitaxial growth of visible to infra-red transparent conducting In2O3 nanodot dispersions and reversible charge storage as a Li-ion battery anode

Unique bimodal distributions of single crystal epitaxially grown In2O3 nanodots on silicon are shown to have excellent IR transparency greater than 87% at IR wavelengths up to 4 μm without sacrificing transparency in the visible region. These broadband antireflective nanodot dispersions are grown using a two-step metal deposition and oxidation by molecular beam epitaxy, and backscattered diffraction confirms a dominant (111) surface orientation. We detail the growth of a bimodal size distribution that facilitates good surface coverage (80%) while allowing a significant reduction in In2O3 refractive index. This unique dispersion offers excellent surface coverage and three-dimensional volumetric expansion compared to a thin film, and a step reduction in refractive index compared to bulk active materials or randomly porous composites, to more closely match the refractive index of an electrolyte, improving transparency. The (111) surface orientation of the nanodots, when fully ripened, allows minimum lattice mismatch strain between the In2O3 and the Si surface. This helps to circumvent potential interfacial weakening caused by volume contraction due to electrochemical reduction to lithium, or expansion during lithiation. Cycling under potentiodynamic conditions shows that the transparent anode of nanodots reversibly alloys lithium with good Coulombic efficiency, buffered by co-insertion into the silicon substrate. These properties could potentially lead to further development of similarly controlled dispersions of a range of other active materials to give transparent battery electrodes or materials capable of non-destructive in situ spectroscopic characterization during charging and discharging.