Advanced search


Knowledge area




208 results, page 1 of 10

Urban form, transit supply, and travel behavior in Latin America: Evidence from Mexico's 100 largest urban areas

Erick Guerra Camilo Caudillo Paavo Monkkonen Jorge Alberto Montejano Escamilla (2018)

This paper examines the relationship between urban form, transportation supply, and individuals' mode choice across Mexico's 100 largest urban areas. After documenting variation in mode choice, urban form, and vehicle ownership, we fit a multinomial logit model to data from 2.5 million commuters who reported a work commute on the 2015 Intercensus. We estimate whether a person commutes by transit, car, or walking/biking as a function of commuters' gender, age, employment status, household income, and seven measures of urban form and transportation supply. Across urban areas, commuters are less likely to drive in dense urban areas where jobs are spatially concentrated jobs and near population centers. Commuters are also less likely to drive in areas with better public transit supply and less roadway. Collectively the measures of urban form are as strongly related to the probability someone commutes to work by car as household income. Population density plays a particularly strongly role with an estimated elasticity four times as strong as recent studies from US urban areas. Taken together, our findings suggest that land use planning and transportation investments can and do influence commute patterns. Recent public policies have almost certainly contributed to increased, rather than decreased driving and associated congestion, pollution, and traffic fatalities.

Article

Transit Urban form Travel behavior Mode choice CIENCIAS SOCIALES GEOGRAFÍA GEOGRAFÍA REGIONAL GEOGRAFÍA URBANA GEOGRAFÍA URBANA

Urban Form and Productivity in Mexico 1995-2015

Jorge Alberto Montejano Escamilla CAMILO ALBERTO CAUDILLO COS Paavo Monkkonen Erick Guerra (2020)

Worldwide, urban policies are encouraging more compact development in cities arguing environmental sustainability and higher economic productivity. However, there is limited evidence for the relationship between urban form and economic productivity outside high-income countries. While we know that workers in larger cities are more productive, existing empirical evidence on the relationship between compactness and productivity is only from high-income countries, with a productive service sector. Given that the economic base of many cities in Mexico consists of land-intensive manufacturing activities, policies promoting urban compactness have potential negative impacts on economic growth by restraining expansion. In this paper we explore the relationship in time between urban form/spatial structure and economic productivity in Mexico, by testing the hypothesis that growing in a compact way is positively associated with labor productivity. That hypothesis is not completely rejected because several measures of urban form are positively correlated with higher levels of productivity, and other measures are negatively correlated. As the principal findings are counterintuitive, they raise questions about what is the accepted knowledge of urban growth.

Article

Urban Form urban structure productivity manufacturing CIENCIAS SOCIALES GEOGRAFÍA GEOGRAFÍA ECONÓMICA DESARROLLO REGIONAL DESARROLLO REGIONAL

Sustainability Assessment of the Residential Land Use in Seven Boroughs of the Island of Montreal, Canada.

RICARDO ENRIQUE VEGA AZAMAR RABINDRANARTH ROMERO LOPEZ NORMA ANGELICA OROPEZA GARCIA (2015)

"High resource utilization in the residential sector, and the associated environmental

impacts, are central issues in the growth of urban regions. Land-use urban planning is a

primary instrument for the proper development of cities; an important point is the

consideration of the urban form’s influence on resource utilization intensity".

Article

Emergy evaluation Residential land use Domestic consumption Resource utilization intensity Urban planning Urban form INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS TECNOLOGÍA DE LA CONSTRUCCIÓN VIVIENDAS

Average conditions of thermal stress in Mexican cities with more than one million inhabitants in the face of climatic change

ADALBERTO TEJEDA MARTINEZ ELDA LUYANDO LOPEZ DOMINGO ERNESTO JAUREGUI OSTOS (2011)

Human bioclimatic scenarios are presented for Mexican cities with more than a million inhabitants. For this, both urban and global warming were considered, the former having been inferred from demographic data, and the latter from the output of general circulation models. Thus, it was possible to estimate increases in temperature and modifications in hygrometric conditions, which were then used to estimate the human bioclimate for the period of 1981-2000 and the decades of 2030 and 2050, as well as the domestic electrical consumption for air-conditioning in housing resulting there from.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA bioclimatic scenarios global warming urban hygrometric conditions temperature

Localización de puntos de transferencia para transporte urbano y suburbano. Una alternativa metodológica para el caso de la Zona Urbana Toluca, México

EUSEBIO CARDENAS GUTIERREZ (2001)

The present work contains a terminals location proposal for urban and suburban transportation of Toluca city urban area, wich was elaborated as follows: 1. Conceptualization of terminals or transfer points, as a transportation infrastructure component. 2. Identification and analysis, under a systems approach, of the main variables that affect terminals location for urban transportation: land use with regard to population density and urban center activities; origins and destinations of transportation service; location and characteristicis of arterial streets; location of existing spontaneous transfer points. 3. Proposition of eight urban and suburban transportation terminals and its evaluation through the multiple criteria technique and final proposal of five transfer points in hierarchical order according to adopted criteria.

Article

Multidisciplinarias (Ciencias Sociales) terminals transportation urban passengers CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA

Average conditions of thermal stress in Mexican cities with more than one million inhabitants in the face of climatic change

ADALBERTO TEJEDA MARTINEZ ELDA LUYANDO LOPEZ DOMINGO ERNESTO JAUREGUI OSTOS (2011)

Human bioclimatic scenarios are presented for Mexican cities with more than a million inhabitants. For this, both urban and global warming were considered, the former having been inferred from demographic data, and the latter from the output of general circulation models. Thus, it was possible to estimate increases in temperature and modifications in hygrometric conditions, which were then used to estimate the human bioclimate for the period of 1981-2000 and the decades of 2030 and 2050, as well as the domestic electrical consumption for air-conditioning in housing resulting there from.

Article

CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA bioclimatic scenarios global warming urban hygrometric conditions temperature

Una prueba sobre la especificación de un modelo de regresión

AMANDA LOLITA PINEDA NORMAN (2013)

Tesis (Maestría en Ciencias, especialista en Estadística).- Colegio de Postgraduados, 2013.

Un modelo de regresión lineal múltiple tiene problemas de especificación incorrecta de la forma funcional cuando no explica en forma adecuada la relación entre la variable dependiente y las explicativas observadas. Una prueba sobre la especificación del modelo es la prueba RESET; sin embargo, la prueba ha demostrado tener baja potencia, quedando además poco clara la forma de definir las variables que serán incluidas en la regresión auxiliar que utiliza, presentando por construcción problemas de multicolinealidad. En el presente trabajo se propone una prueba de especificación basada en Multiplicadores de Lagrange y la regresión Lasso Adaptativo (Zou2006) a la cual le llamamos ML-ALasso. Al igual que la prueba RESET, la prueba ML-ALasso se basa en una regresión ampliada del modelo original. Además se propone un método para muestras pequeñas que utiliza la prueba de permutaciones al cual llamamos ML-ALasso-p. Mediante un estudio de simulación se analiza el comportamiento de las pruebas y se comparan con dos pruebas alternativas para verificar una correcta especificación del modelo. Se concluye que el método ML-ALasso tiene un buen desempeño para muestras grandes y el método ML-ALasso-p funciona bien para muestras pequeñas. _______________ A TEST ON THE SPECIFICATION OF A REGRESSION MODEL. ABSTRACT: A multiple linear regression model has problems of incorrect specification of the functional form when not adequately explain the relationship between the dependent variable and the explanatory observed. A test of the model specification is the RESET test, but the test has been shown to have low power while leaving unclear how to define the variables to be included in the auxiliary regression using, disclosing construction multicollinearity problems. In this paper a specification test based on Lagrange Multipliers and Adaptive Lasso (Zou2006) regression which we call ML-ALasso is proposed. Like the RESET test, the ML- ALasso test is based on an extended regression of the original model. In addition a method for small samples using the permutation test which we call ML-ALasso-p is proposed. By a simulation study test behavior is analyzed and compared with two alternative tests to verify proper specification of the model. We conclude that the ML-ALasso method has a good performance for large samples and ML-ALasso-p method works well for small samples.

Master thesis

RESET Lasso adaptativo Multiplicador de Lagrange Prueba de permutaciones Error de especificación Forma funcional RESET test Adaptive Lasso Lagrange Multiplier Permutation Test Misspecification Functional form Estadística Maestría CIENCIAS SOCIALES

Analysis of a micro vertical-axis wind turbine by computational fluids simulation

HECTOR RENE VEGA CARRILLO (2015)

The installed capacity of wind energy around the

world using big horizontal-axis wind turbines (HAWT) has grown

substantially in the last two decades. Likewise, research and

development of vertical-axis wind turbines (VAWT) for small

power applications has been increased during the last seven years.

This paper presents the performance analysis related to the power

output of a micro VAWT with three blades in helicoidal form,

based on computacional fluids dynamics simulation (CFD), using

Ansys Fluentr. In the analysis, several parameters related to

the aerodynamic performance were varied, keeping constant the

sweeping area. To compare results, a mathematical model was

created in Matlabr, using the double-multiple streamtube method

(DMST), which considers variations in relative wind speed

through the wind turbine. Results from both, CFD simulation

and DMST model, applied to the micro turbine are presented.

Producción Científica de la Universidad Autónoma de Zacatecas UAZ

Conference object

INGENIERÍA Y TECNOLOGÍA Vertical-axis wind turbine Helical form Darrieus Double-multiple streamtube

Qubits structure as an enhancement factor of coherence in a one-way quantum computer

NANCY DIANA ANASTACIO MARTINEZ ESTEBAN VALTIERRA PACHECO EUFEMIO GABINO NAVA BERNAL SERGIO FRANCO MAASS (2015)

Present day´s efforts for building up an operative quantum computer soon will take shape. One of the main challenges to this task is to implement qubit coherence in a practical way. We make emphasis on the structure of the nuclear qubits in a one-way quantum computer as a source of coherence enhancement. The form factor, accounting for the nuclear qubit structure of the model, is the magnetogyric ratio γ (more commonly called the gyromagnetic ratio). We collect experimental values for γ and calculate the respective times of coherence T h , for a number of materials. A parametrization is also given for γ , in terms of the atomic number, whose agreement with the experiment is very good. We also calculate, accurately enough, bounds to the corrections to T h due to spurious dipolar coupling between nuclei because this has not been done in the past. Such corrections are negligible for nearby planes whereas for remote planes they might be of considerable size. It is concluded that the nuclei states last longer than their electronic counterpart. However, this stability of nuclei qubits limits the speed at which the computer can carry out instructions and process the information.

Article

computación qubit structure form factors dipolar coupling spurious decoherence time CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Integrable Abel equations and Vein's Abel equation

Stefan C. Mancas HARET CODRATIAN ROSU (2016)

"We first reformulate and expand with several novel findings some of the basic results in the integrability of Abel equations. Next, these results are applied to Vein's Abel equation whose solutions are expressed in terms of the third-order hyperbolic functions, and a phase space analysis of the corresponding nonlinear oscillator is also provided. Copyright © 2015 John Wiley & Sons, Ltd."

Article

Abel equation Appel invariant Normal form Canonical form Third-order hyperbolic function CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA