#Carlos echeverri calidad del aire full
#Carlos echeverri calidad del aire software

Moreover, their usage creates dependency on proprietary solutions, which can hinder the possibility of evolving the data processing and analysis protocols.

#Carlos echeverri calidad del aire software

However, the costly state-of-the-art software applications developed by major vendors are inaccessible to many cities and townships in the developing world. Automated software tools can facilitate drawing conclusions based on the information contained in the data, limiting subjective judgment and providing repeatability. Air quality data acquisition, cleaning and authentication are necessary and crucial preliminary phases to support descriptive, predictive and prescriptive models and to ensure that aggregated and high-quality information is delivered to the central and local governments, decision makers and citizens. However, processing large sets of data to extract statistically valid evidence poses many challenges from both the conceptual and technical viewpoints. Recent technological advances in collecting data on emission sources, meteorological conditions and concentration of air pollutants in urban areas, offer invaluable opportunities for the better understanding of air quality problems.

#Carlos echeverri calidad del aire full

In order to minimize the negative spillovers during the full implementation of TM, expected to last until 2015, integration of the traditional and new systems should be carried on, and strict regulation of the traditional public transport system should be crafted. Consequently, although the CBA for the first phase of the corridors covered by TM is positive, once these additional measures are taken into consideration, the net effect is negative due primarily to increases in travel time for passengers using the traditional transport system.

However, the type of transition adopted for the remaining transport corridors not covered by TM caused unforeseen negative spillovers, as a consequence of slow scrapping rates and bus and routes relocation. In addition, congestion, pollution and traffic accidents plummeted in TM corridors. The new organization had a sizeable impact on TM users’ by improving traveling conditions significantly. The adoption of this new model needed to resolve delicate political economy issues that characterized private transport systems in many developing countries. The new transit system is a hybrid model that combines public planning of the network structure, route tendering conditions, regulation and supervision, as well as private operation of the separated functions of revenue collection and transport service.

The purpose of this paper is to analyze Bogotá’s mass transit system before and after TM, study the political economy of its adoption process and conduct a cost-benefit analysis (CBA) of the first phase of the system. To address all of these issues, the municipal and national governments designed and put in place a new mass transit system named TransMilenio (TM), which came into operation in January 2001. The average travel time to work was one hour and ten minutes, obsolete buses provided public transport, traffic generated 70 percent of air pollution and there were frequent traffic accidents. By the end of the 1990s, inefficiency, excess supply and low service quality characterized the mass transit system of Bogotá.