Rebuilding a community: lessons from New Orleans

Whether low-income communities are struggling to rebuild after a hurricane or after long neglect, the challenges often seem insurmountable. The New Orleans 9th Ward’s inclusive approach to decision making shows that the best revitalization plans are those with the broadest buy-in.Community development

Advanced thermal barrier coating systems

Current state-of-the-art thermal barrier coating (TBC) systems consist of partially stabilized zirconia coatings plasma sprayed over a MCrAlY bond coat. Although these systems have excellent thermal shock properties, they have shown themselves to be deficient for a number of diesel and aircraft applications. Two ternary ceramic plasma coatings are discussed with respect to their possible use in TBC systems. Zirconia-ceria-yttria (ZCY) coatings were developed with low thermal conductivities, good thermal shock resistance and improved resistance to vanadium containing environments, when compared to the baseline yttria stabilized zirconia (YSZ) coatings. In addition, dense zirconia-titania-yttria (ZTY) coatings were developed with particle erosion resistance exceeding conventional stabilized zirconia coatings. Both coatings were evaluated in conjunction with a NiCr-Al-Co-Y2O3 bond coat. Also, multilayer or hybrid coatings consisting of the bond coat with subsequent coatings of zirconia-ceria-yttria and zirconia-titania-yttria were evaluated. These coatings combine the enhanced performance characteristics of ZCY with the improved erosion resistance of ZTY coatings. Improvement in the erosion resistance of the TBC system should result in a more consistent delta T gradient during service. Economically, this may also translate into increased component life simply because the coating lasts longer

Voice, identity, and knowledge: Teaching and learning in an urban classroom

This study explored the dynamics that impact opportunity for students to share knowledge, and express beliefs, values, and opinions in the context of an eighth grade classroom. A multi-methods approach was used to examine factors that contributed to the enhancement or diminishment of possibilities for student voice. The role of the teacher\u27s voice in this dynamic became an unexpectedly powerful factor in opportunities for students to share their knowledge and ideas. Findings suggested that the ways in which students were encouraged or discouraged from participating impacted their learning and identities. The intricate and fundamental ways in which voice was tied to knowledge construction, identity, and agency was an unexpected but central finding. Discourses regarding schooling, its role and purposes, adolescents, teaching and learning, and the role of adults in society were particularly relevant to this study as they related to teacher and student construction of their identities, knowledge and voice. The significant role of teachers\u27 ideologies shaped by sociocultural, economic, and historical context in informing the pedagogical choices, content of the formal and informal curriculum, and interactions with students is highlighted. The ways in which students variously accepted, resisted, rejected, and negotiated messages conveyed about their experiences, academic performance, and identities is explored, as are themes of care and responsibility as defined by teacher and students. Finally implications for teachers, administrators, policy makers, teacher educators, and further research are discussed

FARM-LEVEL PERSPECTIVES ON THE IMPACT OF DOMESTIC SUPERMARKETS ON KENYA'S FRESH FRUITS AND VEGETABLES SUPPLY SYSTEM

The rise of supermarkets in Kenya has given rise to a new group of medium-sized farms managed by well-educated farmers. Focusing on kale, the essay shows that nearly all supermarket-channel farmers have the capacity to supply larger volumes year round and have transportation vehicles, an irrigation system, a packing shed, a cellular phone, and so on, pointing to the existence of a threshold capital vector which farmers must have in order to access supermarkets. Especially farm size and irrigation were found to be significant determinants of participation in the supermarket channel. Kale suppliers to supermarkets use more capital intensive production technologies, leading to average labor and land productivities which are 60-70% higher than in the traditional channel. Eighty percent of labor consists of hired workers, indicating that these farmers could be important in alleviating poverty for rural households with little or no land. While most traditional-channel kale farmers sell to brokers and get a price that lets them break-even at best, supermarket-channel farmers have a 40% gross profit margin. These margins and lower market risks in the supermarket channel have resulted in a strong growth dynamic of supermarket-channel farmers which have doubled the size of their operations over the last five years.Marketing,

Using Automated Task Solution Synthesis to Generate Critical Junctures for Management of Planned and Reactive Cooperation between a Human-Controlled Blimp and an Autonomous Ground Robot

This thesis documents the use of an approach for automated task solution synthesis that algorithmically and automatically identifies periods during which a team of less-than-fully capable robots benefit from tightly-coupled, coordinated, cooperative behavior. I test two hypotheses: 1) That a team’s performance can be increased by cooperating during certain specific periods of a mission and 2) That these periods can be identified automatically and algorithmically. I also demonstrate how identification of cooperative periods can be performed both off-line prior to the application and reactively during mission execution. I validate these premises in a real-world experiment using a human-piloted Unmanned Aerial Vehicle (UAV) and an autonomous mobile robot. For this experiment I construct a UAV and use an off-the-shelf robot. To identify the cooperative periods I use the ASyMTRe task solution synthesis system, and I use the Player robot server for control tasks such as navigation and path planning. My results show that teams employing cooperative behaviors during algorithmically identified cooperative periods exhibit better performance than non-cooperative teams in a target localization task. I also present results showing an increased time cost for cooperative behaviors and compare the increased time cost of two cooperative approaches that generate cooperative periods prior to and during mission execution

An Intelligent Robot and Augmented Reality Instruction System

Human-Centered Robotics (HCR) is a research area that focuses on how robots can empower people to live safer, simpler, and more independent lives. In this dissertation, I present a combination of two technologies to deliver human-centric solutions to an important population. The first nascent area that I investigate is the creation of an Intelligent Robot Instructor (IRI) as a learning and instruction tool for human pupils. The second technology is the use of augmented reality (AR) to create an Augmented Reality Instruction (ARI) system to provide instruction via a wearable interface. To function in an intelligent and context-aware manner, both systems require the ability to reason about their perception of the environment and make appropriate decisions. In this work, I construct a novel formulation of several education methodologies, particularly those known as response prompting, as part of a cognitive framework to create a system for intelligent instruction, and compare these methodologies in the context of intelligent decision making using both technologies. The IRI system is demonstrated through experiments with a humanoid robot that uses object recognition and localization for perception and interacts with students through speech, gestures, and object interaction. The ARI system uses augmented reality, computer vision, and machine learning methods to create an intelligent, contextually aware instructional system. By using AR to teach prerequisite skills that lend themselves well to visual, augmented reality instruction prior to a robot instructor teaching skills that lend themselves to embodied interaction, I am able to demonstrate the potential of each system independently as well as in combination to facilitate students\u27 learning. I identify people with intellectual and developmental disabilities (I/DD) as a particularly significant use case and show that IRI and ARI systems can help fulfill the compelling need to develop tools and strategies for people with I/DD. I present results that demonstrate both systems can be used independently by students with I/DD to quickly and easily acquire the skills required for performance of relevant vocational tasks. This is the first successful real-world application of response-prompting for decision making in a robotic and augmented reality intelligent instruction system

Bilateral attentional advantage on elementary visual tasks

We examined interactions between and within the left and right visual hemifields using elementary visual tasks. Each trial required identifying a letter at fixation and then either discriminating the orientation of (experiment I) or detecting (experiment 2) peripheral Gabor targets. On half the trials Gabor distracters were presented between the Gabor targets, and were either restricted to one lateral hemifield (unilateral condition) or presented across the left and right hemifields (bilateral condition). Orientation discrimination and detection each exhibited bilateral superiority only when distracters were present. The results confirm bilateral superiority in attentional selection, even on these most elementary visual tasks. (C) 2009 Elsevier Ltd. All rights reserved

Ammonia uptake and release in the MnX₂–NH₃ (X = Cl, Br) systems and structure of the Mn(NH₃)nX₂ (n = 6, 2) ammines

Hexa-ammine complexes, Mn(NH<sub>3</sub>)<sub>6</sub>X<sub>2</sub> (X = Cl, Br), have been synthesized by ammoniation of the corresponding transition metal halide and characterized by Powder X-ray diffraction (PXRD) and Raman spectroscopy. The hexa-ammine complexes are isostructural (Cubic,Fm-3m, Z = 4; a = 10.2742(6) Å and 10.527(1) Å for X = Cl, Br respectively). Temperature programmed desorption (TPD) demonstrated that ammonia release from Mn(NH<sub>3</sub>)<sub>6</sub>X<sub>2</sub> complexes occurred in three stages corresponding to the release of 4, 1 and 1 NH<sub>3</sub> equivalents respectively. The chloride and bromide both exhibit a deammoniation onset temperature below 323 K. The di-ammoniates from the first desorption step were isolated during TPD measurements and their crystal structures determined by Rietveld refinement against PXRD data (X = Cl: orthorhombicCmmm, a = 8.1991(9) Å, b = 8.2498(7) Å, c = 3.8212(4) Å, Z = 2; X = Br: orthorhombic Pbam, a = 6.0109(5) Å, b = 12.022(1) Å, c = 4.0230(2) Å, Z= 2)

Arresting woodland bird decline in Australian agricultural landscapes: potential application of the European agri-environment model

This paper considered the applicability of the European model of land stewardship payments, in particular its support for biodiversity conservation in agricultural landscapes, to an Australian context. More broadly, the research approach described in the paper may also be applied to assessing the suitability of overseas stewardship schemes to the provision of any ecoservice in Australia, such as carbon sequestration and floodwater regulation

Improving the Impact of Market Reform on Agricultural Productivity in Africa: How Institutional Design Makes a Difference

Improving the Impact of Market Reform on Agricultural Productivity in Africa: How Institutional Design Makes a Difference Abstract: This paper reviews the emerging empirical record of agricultural marketing policy reform and agricultural productivity, drawing from research on food access and agricultural productivity supported by USAID’s Africa Bureau on seven countries in West, Eastern, and Southern Africa. We also examine key factors constraining past and future performance of the food systems in these countries. The paper concludes by identifying a set of policy issues for further consideration that would help provide the investment incentives to promote productivity growth for the millions of low-input semi-subsistence rural households in the region.food security, food policy, market reform, Agricultural and Food Policy, Marketing, Productivity Analysis, Downloads June 2008 - July 2009: 40, Q13,