Neighborhood Crime and Travel Behavior: An Investigation of the Influence of Neighborhood Crime Rates on Mode Choice, MTI Report 07-02

While much attention has been given to the influence of urban form on travel behavior in recent years, little work has been done on how neighborhood crimes affect this dynamic. This research project studied seven San Francisco Bay Area cities, and found substantiation for the proposition that neighborhood crime rates have an influence on the propensity to choose non-automotive modes of transportation for home-based trips. Specifically, high vice and vagrancy crime rates were associated with a lowered probability of choosing transit in suburban cities for both work and non-work trips, high property crime rates were associated with a lower probability of walking for work trips in urban cities and inner-ring suburban cities, high violent crime rates with a lower probability of walking for work trips in suburban study cities, while higher property crime rates in San Francisco were associated with an increased probability of walking for non-work trips. While the signs of these significant relationships generally conformed to the author’s expectations—i.e., that high crime rates reduce the probability of choosing non-automotive modes of travel—the authors did not find statistically significant relationships for all city/trip model runs, suggesting that these relationships differ depending on the urban form and trip type contexts

Adaptive-wall wind-tunnel research at NASA-Ames Research Center

Adaptive wall wind tunnel research is summarized. Small scale two and three dimensional wind tunnel experiments and numerical experiments with a three dimensional adaptive wall simulator are included. A NACA 0012 airfoil was tested in a 25 by 13 cm slotted wall test section. Airflow through the test section walls was controlled by adjusting the pressures in segmented plenums. Interference free conditions were successfully attained in subsonic and transonic flows. For the three dimensional experiment, the 25 by 13 cm wind tunnel was modified to permit cross stream wall adjustments. The test model was a semispan wing mounted to one sidewall. Wall interference was substantially reduced at several angles of attack at Mach 0.60. A wing on wall configuration was also modeled in the numerical experiments. These flow simulations showed that free air conditions can be approximated by adjusting boundary conditions at only the floor and ceiling of the test section. No sidewall control was necessary. Typical results from these experiments are discussed

Diatom communities of travertine-precipitating springs on a gradient of anthropogenic disturbance in the Sandia Mountains, New Mexico

Carbonate-rich waters of travertine-precipitating springs facilitate unique physiochemical environments that support distinct diatom species assemblages adapted to the environmental stress of constant carbonate precipitation. Diatom communities in spring systems may be further limited by the impacts of historical and ongoing anthropogenic disturbance, which includes recreational activity and hydrologic modification of springs using spring boxes and wells. This study focused on impacts of water chemistry and anthropogenic disturbance on diatom assemblages found in travertine-precipitating springs. Data were collected in the fall of 2016 and spring of 2017 at eight spring sites, including six known to precipitate travertine, in the Sandia Mountains of central New Mexico. Water chemistry, benthic diatoms, sediment composition, percent organic matter, and categorical disturbance variables were analyzed. Hydrochemical analysis showed five of six springs known to precipitate travertine were actively forming travertine (saturation index of calcite near or greater than 1.00) during the fall sampling period. Diatom taxa observed in springs were indicative of active travertine precipitation (e.g., Diatoma mesodon, Halamphora montana), higher conductivities (e.g., Diploneis oblongella, Pinnularia spp.), and degree of hydrologic modifications to springs (e.g., Eucocconeis flexella, Gomphonema truncatum). Species richness was greater in non-travertine precipitating springs and diatom density varied among the springs, but was greater in springs during the spring sampling season. Diatom assemblage analysis, disturbance characterization, and other biological assessments can be used to prioritize restoration of springs with unique habitats, such as travertine-precipitating springs

LIBERALIZATION, PUBLIC SPENDING AND CONVERGENCE IN LATIN AMERICA: AN SPATIAL ECONOMETRIC MODEL

The study focuses on the analysis of economic growth of the Latin American countries, during the period 1950-2000 The methodology of the paper is based on the use of spatial econometric thechniques applied to a cross section and panel data. The results showed conditional convergence for the region from 1950 to 1975, and both absolute and conditional divergence from 1980 to 2000.Convergence; Latin America

Relaciones asociativas como instrumento de cambio en la gestión pública

The aim of this article is to propose a framework for analysis to introduce the reader to the debate on public, private and social associative relations (RaPPS), proposed by the author as an instrument of change in public management. Based on the tendency of governments to act in a network, the RaPPS allow governments to enhance the relational capacities of their public administrations, in the provision of their services or even in some of the phases of the public policy process. In the article, it is tried to give some clues that characterize an associative relation, of a traditional public-private association. In exploring three municipal cases of associative relations, two in Mexico and one in Chile, the reader is drawn to the attributes that were identified in the three types of associative relations between government, civil society and business, in order to contribute inputs to their own reflection. The application of techniques of observation, interviews and documentary review allowed gathering evidence about the complexity in the functioning of associative relations and the barriers of sustainability that they face. It proposes the existence of three types of RaPPS: a) deliberative, b) corporate and c) participatory.El objetivo del artículo es proponer un marco de análisis para introducir al lector al debate de las relaciones asociativas pública, privada y social (RaPPS), propuestas por el autor como instrumento de cambio en la gestión pública. Con base en la tendencia de los gobiernos para actuar en red, las RaPPS permiten a los gobiernos potenciar las capacidades relacionales de sus administraciones públicas, en la prestación de sus servicios o incluso en alguna de las fases del proceso de política pública. En el artículo, se pretende dar algunas pistas que caractericen una relación asociativa, de una tradicional asociación público- privado. Al explorar tres casos municipales de relaciones asociativas, dos en México y uno en Chile, se dibuja al lector los atributos que se identificaron en los tres tipos de relaciones asociativas entre gobierno, sociedad civil y empresa, para aportar insumos hacia su propia reflexión. La aplicación de técnicas de observación, entrevistas y revisión documental, permitió recabar evidencia acerca de la complejidad en el funcionamiento de relaciones asociativas y las barreras de sustentabilidad que enfrentan. Se propone la existencia de tres tipos de RaPPS: a) deliberativa, b) corporativa y c)participativa