Un Sistema de Administración de Pavimentos (SAP) es un conjunto coordinado de operaciones relacionadas con la planificación, construcción y conservación de todos los elementos que pertenecen a la infraestructural vial, con el fin de establecer una metodología de seguimiento y evaluación, desarrollando criterios de decisión y contribuyendo en el proceso de evaluación de los impactos esperados en las decisiones tomadas. Los SAP tienen su origen a mediado de los años 70’s adoptando el lema “De invertir ahora ó pagar mucho dinero después” han sido desarrollados e implementados en muchas agencias encargadas de administrar los recursos a nivel mundial, teniendo una gran aceptación por ser una herramienta que ayuda al momento de comparar alternativas de solución y contribuir de forma eficiente en la toma de decisiones de intervención. 

The serviceability models available on the literature are generally applicable to interstate highways and rural roads. The present paper aims to develop alternative modelling approaches that can be applied when assessing the pavement serviceability of urban roads in developing countries. More than sixty (60) rigid urban pavement sections with different surface characteristics were evaluated. Performance indexes such as the International Roughness Index (IRI) and the Pavement Condition Index (PCI) were measured on each pavement section. Deterministic and probabilistic models were developed to correlate pavement performance indicators with the users' assessment of each pavement section. Moreover, threshold limits for the acceptance of the IRI and PCI were also proposed using a probabilistic approach. In line with previous studies, Colombian users have higher tolerance than users from developed countries towards accepting pavement in poor conditions. Particularly, results suggest a higher tolerance towards urban roads with high IRI and low PCI values. Finally, the models and thresholds proposed in this research could be used to define prioritisation policies that could help road agencies in their decision-making process at the network level, saving time and money in public investment, and thus achieve an increase in the welfare of the urban population of countries with similar sociocultural characteristics. Furthermore, the methodological framework applied in this research effort may be useful for agencies and governments seeking to develop and/or improve their current PMS

Roughness is the main feature of the pavement surface that defines user comfort. Pavement roughness is generally defined as irregularities in the pavement surface that adversely affect ride quality, specifically user perception of the road condition. This paper highlights the limitations associated with the evaluation and implementation of the international roughness index (IRI) on urban roads. The paper focuses on (a) roughness evaluation with full-scale profilers and (b) conditions particular to urban roads—namely, traffic, intersections, and operating speeds. Given that the speed of urban networks is typically less than the 80 km/h used in the IRI quarter-car model, the implementation of the IRI model on urban roads was evaluated. Even though a given pavement surface reported a unique IRI value, user experience of the profile depended on the travel speed. This result was evidence that user perceptions of road condition are highly influenced by travel speed. The results suggested the need to develop a roughness index that captures the unique characteristics of urban roads and can estimate the road condition as perceived by users. For that reason, this research study focused on establishing thresholds for IRI on the basis of the weighted vertical acceleration parameter as an aid to assessing user perception. The proposed method allows the maximum allowable IRI value for a given road to be established on the basis of the road’s operational speed. The results indicated that IRI thresholds agreed with international and local Colombian standards.

El artículo se refiere a las diferentes bases genéticas de las marihuanas de baja, media y alta potencia, y especialmente a las efectos adversos y respuestas biológicas y comportamentales que elicitan los clones élite de marihuanas autoflorecentes y feminizadas.

Desde inicios del siglo XX términos como:droga, adicción, dependencia, rehabilitación entre otros, han entrado en el lenguaje cotidiano de las sociedades post-industriales, donde las problemáticas ligadas al consumo de sustancias psicoactivantes (SPA) se han convertido en un asunto de salud públicay en un fenómeno social sin precedentes. Los términos popularizados que hacen referencia a este tipo de problemáticas, se han convertido no solo en categorías explicativas sino en caballos de batalla de una sociedad que sedebate entre dos polos contrarios. El primero es la alta valoración a los ideales de autodeterminación y de libertad personal de los individuos que a ella pertenecen. El segundo es la posición central que ocupan los ideales de productividad propios de la lógica capitalista que, aunque no sean necesariamente irreconciliables chocan frecuentemente con los primeros