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Concrete median barriers are designed to mitigate serious cross-median crashes by preventing penetration of errant vehicles into oncoming traffic. When implemented in flood-prone areas, however, solid concrete median barriers can act as a dam to floodwaters, as recently seen in Texas during Hurricane Harvey or in Louisiana and Pennsylvania following severe storms. These severe weather events raise the height of floodwaters and increase the severity of flooding on highways and surrounding roads and communities. In this study, new median barrier options with openings were investigated as a way to reduce flooding. Finite element simulations were used to aid investigation and evaluation of the designs, and laboratory testing was performed to evaluate the hydraulic efficiency of barrier designs in a variety of simulated flood conditions. A concrete single-slope profile median barrier with a large scupper was selected for crash testing following Manual for Assessing Safety Hardware (MASH) Test Level 4 impact conditions and evaluation criteria. The median barrier design was deemed MASH compliant and is ready for implementation in areas susceptible to flooding, with the goals of reducing flooding severity, decreasing associated risk to motorists, and reducing the level of flood damage to both highways and surrounding areas.

Tropical-biodiversity conservation has changed radically over the past generation. Until the early 1980s, conventional wisdom held that central governments should manage all conservation efforts in developing countries. Over the past 15 years or so, scholars, conservation practitioners, and policymakers have advocated an alternative approach based on bottom-up direction by local communities in response to real or perceived government malfeasance, misfeasance, or nonfeasance under the previous top-down model. Now that some of the pitfalls of community authority over conservation decisions have become apparent, the question is what, if any, best-bet strategies exist if the institutions of both government agencies and communities are ill equipped to handle the challenges of biodiversity conservation? (We follow Douglass North's [1990] definition of institutions as “the rules of the game in a society or, more formally, ... the humanly derived constraints that shape human interaction[p. 3].” Thus, we distinguish between organizations and institutions. For example, a bank is an organization, but within it are many formal and informal rules - institutions - that guide individuals' behavior.).

In this paper, we address the broad question of where to locate authority for tropical biodiversity conservation. In so doing, we advance four claims. First, the current fashion for CBNRM overreaches the indisputable place of local communities in tropical conservation efforts. An unfortunate irony of the current celebration of local authority is that it facilitates the abdication of global responsibility. Second, given variability in scale and institutional capability, hybrid designs involving multiple layers of nested institutions offer the most promise. Third, the greatest challenge to implementing such designs is the (often growing) weakness of existing tropical institutions at all levels. Fourth, rehabilitating such institutions, facilitating ongoing coordination among them, and introducing new institutional forms appropriate to particular conservation challenges will require, at both international and national levels, significant policy reorientations and greater commitments of financial and technical assistance.

Permeable Friction Course (PFC) is a layer of porous asphalt pavement with a thickness of up to 50 millimeters overlain on a conventional impervious hot mix asphalt or Portland cement concrete roadway surface. PFC is used for its driver safety and improved stormwater quality benefits associated with its ability to drain rainfall runoff from the roadway surface. PFC has recently been approved as a stormwater best management practice in the State of Texas. The drainage properties of PFC are typically considered to be governed primarily by two hydraulic properties: porosity and hydraulic conductivity. Both of these hydraulic properties are expected to change over the life of the PFC layer due to clogging of the pore space by trapped sediment. Therefore, proper measurement of the hydraulic properties can be problematic. Laboratory and field tests are necessary for accurately determining the hydraulic conductivity of the PFC layer in order to ensure whether the driver safety and water quality benefits will persist in the future. During testing, PFC experiences a nonlinear flow relationship which can be modeled using the Forchheimer equation. Due to the two-dimensional flow patterns created during testing, the hydraulic conductivity cannot be directly measured. Therefore, numerical modeling of the two-dimensional nonlinear flow relationship is required to convert the measureable flow characteristics into the theoretical flow characteristics in order to properly determine the isotropic hydraulic conductivity. This numerical model utilizes a new scalar quantity, defined as the hydraulic conductivity ratio, to allow for proper modeling of nonlinear flow in two-dimensional cylindrical coordinates. PFC core specimens have been extracted from three different roadway locations around Austin, Texas for the past four years (2007 to 2010). Porosity values of the core specimens range from 12% to 23%, and the porosity data suggest a statistical decrease over time due to trapped sediment in the pore space. A series of constant head tests used in the laboratory and a falling head test used in the field are recommended for measurement of PFC hydraulic characteristics using a modified Forchheimer equation. Through numerical modeling, regressions equations are presented to estimate the hydraulic conductivity and nonlinear Forchheimer coefficient from the measureable hydraulic characteristics determined during experimental testing. Hydraulic conductivity values determined for laboratory core specimens range from 0.02 centimeters per second (cm/s) to nearly 3 cm/s. Field measurements of in-situ hydraulic conductivity vary over a range from 0.6 cm/s to 3.6 cm/s. The results of this research provide well-defined laboratory and field methods for measurement of the isotropic hydraulic conductivity of PFC experiencing two-dimensional nonlinear flow and characterized by the Forchheimer equation. This methodology utilizes a numerical model which presents a proper solution for nonlinear flow in two-dimensions.

Macromedia's Contribute allows Web Professionals to save the time spent performing content updates, by devolving the responsibility and know-how back to the content owners. You identify which areas of which pages users are allowed to update, and they can do this with no technical know-how and with no risk of breaking the site. The net result? They get content updated when they need it - and you get time to spend on Web Design. After all, isn't that why you got into the Web in the first place? This book teaches you all you need to know on setting up the system ... and, uniquely, you're entitled to unlimited free downloads of the glasshaus Contribute End-User Training Guide. By distributing it to the content owners, you empower them and liberate yourself. What this book covers: Site Definitions and Connections Links, Images, and Non-HTML Documents Customizing Contribute Best Practices Selling Contribute to your users and management Training users Supporting Contribute Using Templates in Contribute Editing dynamic web sites with server-side includes From the Publisher This book is for web professionals and site owners who will administer Contribute, and those responsible for training end-users in an organization.