A Sensory Input System for Autonomous Mobile Robots

In order to accomplish navigation in an similar world a robot must be able to build and update its own world map continuously and in real time. This paper proposes a sensory input system based on the fusion of simple low-resolution vision with directed high-resolution sonar. The basic idea is to use a simple vision system to locate the position in which an obstacle lies, and then use an ultrasonic rangefinder to determine the depth of the object and to gain clues about its shape. By fusing two simple systems we attempt to exploit the strengths of each while maintaining an acceptable computational cost. An idealized example is given and we discuss the possibilities and some of the problems

Continuous Homotopies for the Linear Complementarity Problem

There are various formulations of the linear complementarity problem as a Kakutani fixed point problem, a constrained optimization, or a nonlinear system of equations. These formulations have remained a curiosity since not many people seriously thought that a linear combinatorial problem should be converted to a nonlinear problem. Recent advances in homotopy theory and new mathematical software capabilities such as HOMPACK indicate that continuous nonlinear formulations of linear and combinatorial problems may not be far-fetched. Several different types of continuous homotopies for the linear complementarity problem are presented and analyzed here, with some numerical results. The homotopies with the best theoretical properties (global convergence and no singularities along the zero curve) turn out to also be the best in practice

Networks and landscapes: a framework for setting goals and evaluating performance at the large landscape scale

The objective of large landscape conservation is to mitigate complex ecological problems through interventions at multiple and overlapping scales. Implementation requires coordination among a diverse network of individuals and organizations to integrate local‐scale conservation activities with broad‐scale goals. This requires an understanding of the governance options and how governance regimes achieve objectives or provide performance evaluation across both space and time. However, empirical assessments measuring network‐governance performance in large landscape conservation are limited. We describe a well‐established large landscape conservation network in North America, the Roundtable on the Crown of the Continent, to explore the application of a social–ecological performance evaluation framework. Systematic approaches to setting goals, tracking progress, and collecting data for feedback can help guide adaptation. Applying the established framework to our case study provides a means of evaluating the effectiveness of network governance in large landscape conservation

Birds in the playground: Evaluating the effectiveness of an urban environmental education project in enhancing school children's awareness, knowledge and attitudes towards local wildlife.

Children nowadays, particularly in urban areas, are more disconnected from nature than ever before, leading to a large-scale "extinction of experience" with the natural world. Yet there are many potential benefits from children interacting with nature first-hand, including via outdoor learning opportunities. Urban environmental education programmes typically aim to increase awareness and knowledge of local biodiversity and to promote positive attitudes and behaviour towards the environment. However, limited research has been conducted evaluating to what extent these interventions achieve their goals. Here, we explore and assess the influence of a six-week bird-feeding and monitoring project conducted within school grounds ("Bird Buddies") on individual awareness, knowledge and attitudes towards birds by primary school children. This initiative was conducted across eight (sub-)urban primary schools within Brighton and Hove (UK), with 220 participating children (aged 7 to 10). Via pre- and post-project questionnaires, we found evidence for enhanced awareness of local biodiversity, alongside significant gains in both bird identification knowledge and attitudes, which were greatest for children with little prior exposure to nature. Many children expressed a keenness to continue improving the environmental value of their school grounds and to apply elements of the project at home. Student project evaluation scores were consistently positive. Mirroring this, participating teachers endorsed the project as a positive learning experience for their students. One year after the project, several schools were continuing to feed and watch birds. Collectively, the findings from this study highlight the multiple benefits that can be derived from engagement with a relatively short outdoor environmental activity. We therefore believe that such interventions, if repeated locally/longer term, could enhance children's experience with nature in urban settings with combined positive environmental impact

Finding Straight Lines and Curves in Engineering Line Drawings

This paper addresses the problem of distinguishing straight lines from curves in noisy gray tone images, and mathematically representing those lines and curves. A method for locating comers is discussed as well as criteria, based on spline representations, for classifying line segments as straight or curved. Results are given for several typical noisy engineering line drawings

Resiliency in the Age of COVID-19: A Policy Toolkit

Twenty-nine LBJ School authors have come together to craft interdisciplinary and resilience-based policy solutions in one toolkit called Resiliency in the Age of COVID-19. In 18 articles that span public management, climate change, economic development, national security and more, LBJ School policy authors provide a forward-thinking lens on what went wrong and what leadership, public policies and initiatives it will take to fix the system flaws exposed by the pandemic. Published during the LBJ School’s 50th anniversary year, the toolkit also provides a snapshot of the school’s depth and breadth of policy and research engagement at this moment in time.Public Affair

Modeling of thermally driven hydrological processes in partially saturated fractured rock

This paper is a review of the research that led to an in-depth understanding of flow and transport processes under strong heat stimulation in fractured, porous rock. It first describes the anticipated multiple processes that come into play in a partially saturated, fractured porous volcanic tuff geological formation, when it is subject to a heat source such as that originating from the decay of radionuclides. The rationale is then given for numerical modeling being a key element in the study of multiple processes that are coupled. The paper outlines how the conceptualization and the numerical modeling of the problem evolved, progressing from the simplified to the more realistic. Examples of numerical models are presented so as to illustrate the advancement and maturation of the research over the last two decades. The most recent model applied to in situ field thermal tests is characterized by (1) incorporation of a full set of thermal-hydrological processes into a numerical simulator, (2) realistic representation of the field test geometry, in three dimensions, and (3) use of site-specific characterization data for model inputs. Model predictions were carried out prior to initiation of data collection, and the model results were compared to diverse sets of measurements. The approach of close integration between modeling and field measurements has yielded a better understanding of how coupled thermal hydrological processes produce redistribution of moisture within the rock, which affects local permeability values and subsequently the flow of liquid and gases. The fluid flow in turn will change the temperature field. We end with a note on future research opportunities, specifically those incorporating chemical, mechanical, and microbiological factors into the study of thermal and hydrological processes