Two Social Worlds: Social Correlates and Stability of Adolescent Status Groups

Examined adolescents\u27 peer group status in high school using self-report, peer nominations, and archival data collected during 2 consecutive school yrs. 408 students participated in the 1st yr, and 404 students participated in the 2nd yr. 60% of the 2nd yr Ss had also participated in the 1st yr. Higher status students (popular and controversial) had more close friends, engaged more frequently in peer activities, and self-disclosed more than lower status students (rejected and neglected). They were also more involved in extracurricular school activities and received more social honors from their schoolmates. Although the higher status students were more alike than different, controversial adolescents did report more self-disclosure and dating behavior than popular students. Lower status students were also highly similar, although rejected students reported lower grades

Achieving success in engineering: a phenomenological exploration of Latina/o student persistence in engineering fields of study

This study explored the factors that precluded or enhanced Latina/o student persistence in engineering fields of study at Iowa State University (ISU). The study employed a phenomenological methodology. Nora\u27s (2003) Model of Student Engagement and Rendon\u27s (1994) model of validation were used as the theoretical framework. Focus group interviews were employed to explore the pre-college, academic, and social experiences of Latina/o engineering majors while enrolled at ISU. A Model of Latina/o Student Success in Engineering (Figure 5.1) was developed and characterized the three main determinants that facilitated student success in engineering fields of study. The three indicators of success were: (a) pre-college experiences, (b) academic experiences, and (c) social experiences. Pre-college determinants that facilitated success included family support and institutional commitment. Academic experiences that facilitated success were academic engagement and validating interactions among students and faculty. Social experiences also influenced student success by engaging students in relationships of peer support and mentoring. Recommendations were offered to aid the higher education community in implementing student success in their engineering programs

Making a Difference and Facilitating Success: A Model of Chicana/o Student Retention in Chicana/o Studies

For every 100 Chicana/o students only 24 will enroll in college and of those students only seven will obtain a bachelor\u27s degree (Yosso, 2006). These data present the need for increased examination of how students are retained in higher education. Therefore, this study sought to further understand and explore the retention factors contributing to the development and anticipated college completion of a case of Chicana/o studies students working toward the completion of their bachelor\u27s degrees. Findings revealed that retention was impacted by academic factors such as faculty affirmation, and positive contributions to academic development. Social factors contributing to retention included community building, developing and discovering a sense of self, and supportive personal relationships. With a theoretical framework grounded in the model of student engagement and validation theory guiding the analysis, the model of Chicana/o student retention in Chicana/o studies was conceptualized. The model provides an understanding of how validation, relational learning, and engaging academic spaces helped to facilitate increased knowledge acquisition, personal development and professional aspirations. This study provides new knowledge and evolution of existing theories, which speak to retention in understudied contexts like Chicana/o studies. Recommendations and implications are provided

Exploring Body Comparison Tendencies: Women Are Self-Critical Whereas Men Are Self-Hopeful

Our study examined similarities and differences in women’s and men’s comparison tendencies and perfection beliefs when evaluating their face, body shape, and physical abilities, as well as how these tendencies and beliefs relate to their body esteem. College students (90 women and 88 men) completed the Body Esteem Scale (Franzoi & Shields, 1984) and answered questions concerning their social comparison and temporal comparison tendencies related to face, body shape, and physical abilities evaluations as well as personal perfection body beliefs. As predicted, women were more likely than men to compare their face and bodies to other same-sex persons whom they perceived as having either similar or better physical qualities than themselves in those body domains, with their most likely comparison tendency being upward social comparison. More men than women held body-perfection beliefs for all three body domains, and men were most likely to rely on future temporal comparison when evaluating their body shape. Comparison tendencies and perfection beliefs also were differentially related to women\u27s and men\u27s body esteem; whereas women rely on self-critical social comparison strategies associated with negative body esteem, men’s comparison strategies and perfection beliefs are more self-hopeful. Implications for practitioners treating body-image issues are discussed

Active Exterior Cloaking

A new method of cloaking is presented. For two-dimensional quasistatics it is proven how a single active exterior cloaking device can be used to shield an object from surrounding fields, yet produce very small scattered fields. The problem is reduced to finding a polynomial which is approximately one within one disk and zero within a second disk, and such a polynomial is constructed. For the two-dimensional Helmholtz equation, it is numerically shown that three active exterior devices placed around the object suffice to produce very good cloaking.Comment: 4 pages, 3 figures, submitted to Physical Review Letter

Ceramic and coating applications in the hostile environment of a high temperature hypersonic wind tunnel

A Mach 7, blowdown wind tunnel was used to investigate aerothermal structural phenomena on large to full scale high speed vehicle components. The high energy test medium, which provided a true temperature simulation of hypersonic flow at 24 to 40 km altitude, was generated by the combustion of methane with air at high pressures. Since the wind tunnel, as well as the models, must be protected from thermally induced damage, ceramics and coatings were used extensively. Coatings were used both to protect various wind tunnel components and to improve the quality of the test stream. Planned modifications for the wind tunnel included more extensive use of ceramics in order to minimize the number of active cooling systems and thus minimize the inherent operational unreliability and cost that accompanies such systems. Use of nonintrusive data acquisition techniques, such as infrared radiometry, allowed more widespread use of ceramics for models to be tested in high energy wind tunnels

Source amplitudes for active exterior cloaking

The active cloak comprises a discrete set of multipole sources that destructively interfere with an incident time harmonic scalar wave to produce zero total field over a finite spatial region. For a given number of sources and their positions in two dimensions it is shown that the multipole amplitudes can be expressed as infinite sums of the coefficients of the incident wave decomposed into regular Bessel functions. The field generated by the active sources vanishes in the infinite region exterior to a set of circles defined by the relative positions of the sources. The results provide a direct solution to the inverse problem of determining the source amplitudes. They also define a broad class of non-radiating discrete sources.Comment: 21 pages, 17 figure

Mixed-integer-linear-programming-based energy management system for hybrid PV-wind-battery microgrids: Modeling, design, and experimental verification

© 2017 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksMicrogrids are energy systems that aggregate distributed energy resources, loads, and power electronics devices in a stable and balanced way. They rely on energy management systems to schedule optimally the distributed energy resources. Conventionally, many scheduling problems have been solved by using complex algorithms that, even so, do not consider the operation of the distributed energy resources. This paper presents the modeling and design of a modular energy management system and its integration to a grid-connected battery-based microgrid. The scheduling model is a power generation-side strategy, defined as a general mixed-integer linear programming by taking into account two stages for proper charging of the storage units. This model is considered as a deterministic problem that aims to minimize operating costs and promote self-consumption based on 24-hour ahead forecast data. The operation of the microgrid is complemented with a supervisory control stage that compensates any mismatch between the offline scheduling process and the real time microgrid operation. The proposal has been tested experimentally in a hybrid microgrid at the Microgrid Research Laboratory, Aalborg University.Peer ReviewedPostprint (author's final draft

870 micron continuum observations of the bubble-shaped nebula Gum 31

We are presenting here a study of the cold dust in the infrared ring nebula Gum 31. We aim at deriving the physical properties of the molecular gas and dust associated with the nebula, and investigating its correlation with the star formation in the region, that was probably triggered by the expansion of the ionization front. We use 870 micron data obtained with LABOCA to map the dust emission. The obtained LABOCA image was compared to archival IR,radio continuum, and optical images. The 870 micron emission follows the 8 micron (Spitzer), 250 micron, and 500 micron (Herschel) emission distributions showing the classical morphology of a spherical shell. We use the 870 micron and 250 micron images to identify 60 dust clumps in the collected layers of molecular gas using the Gaussclumps algorithm. The clumps have effective deconvolved radii between 0.16 pc and 1.35 pc, masses between 70 Mo and 2800 Mo, and volume densities between 1.1x10^3 cm^-3 and 2.04x10^5 cm^-3. The total mass of the clumps is 37600 Mo. The dust temperature of the clumps is in the range from 21 K to 32 K, while inside the HII region reaches ~ 40 K. The clump mass distribution is well-fitted by a power law dN/dlog(M/Mo) proportional to M^(-alpha), with alpha=0.93+/-0.28. The slope differs from those obtained for the stellar IMF in the solar neighborhood, suggesting that the clumps are not direct progenitors of single stars/protostars. The mass-radius relationship for the 41 clumps detected in the 870 microns emission shows that only 37% of them lie in or above the high-mass star formation threshold, most of them having candidate YSOs projected inside. A comparison of the dynamical age of the HII region with the fragmentation time, allowed us to conclude that the collect and collapse mechanism may be important for the star formation at the edge of Gum 31, although other processes may also be acting.Comment: 15 pages, 10 figures. Accepted for publication in A&