Overview and Challenges of Bogotá’s Transmilenio

Transmilenio was a revolutionary bus rapid transit (BRT) system in Bogotá, Colombia. Launch in 2000, it aimed to mimic the speed of a Metro in facilitating movement of people, but at a fraction of the capital cost. Despite its international acclaim and other cities trying to emulate the system, Transmilenio is not without its share of controversies and challenges. In the paper Bus Rapid Transit: Is Transmilenio a Miracle Cure? Alan Gilbert of University College London explores the background of the system and what crucial actions are necessary for Transmilenio to sustain its core missions of facilitating transportation, maintaining the general interests of poor people, and bringing public and private sectors together to “share responsibilities for the delivery of the service.”

Management was a huge issue in the old traditional bus system, where the various bus companies tried to obtain licenses to operate in the most profitable routes, leading to too many buses at the city center and too few in the outskirts. The competitive nature of the system meant poor bus maintenance and little regard for the well-being of other road users or the passengers. Transmilenio was born out of a desire to modernize the transportation infrastructure without paying the hefty amounts for a Metro. While the concept of BRT isn’t new, Transmilenio was revolutionary for its expansive network and high accolade during the first few years of operation. With dedicated bus lanes and quick loading time, a 2001 survey gave Transmilenio a rating of 4.64 out of 5, with general consensus of saved time and city’s improved cohesion.

Yet criticisms were inevitable, from decay of roads to overcrowding and eventual fare hike. One issue is that a trip on Transmilenio is more expensive than one on traditional bus. This is most pressing for the poorest, and together with overcrowding, has led to slow growth in passenger count. The central agency of Transmilenio, which receives no operating subsidy, has complained about the “unfair competition” from the traditional bus. Gilbert proposes that one solution is to reduce the number of old buses. Scrapping of old buses, in exchange for the license to run new buses, has been remarkably slow though, and many illegal “pirate” buses are still in operation. This is the core of Gilbert’s message that while Transmilenio is a great concept, “complementary changes have to be made in the rest of the sector” if the system is to be sustainable for the future, for Transmilenio by itself cannot solve the city’s transportation challenges.

Sources:

• Alan Gilbert: “Bus Rapid Transit: Is Transmilenio a Miracle Cure?"

Broadacre City

Broadacre City is a city layout concept developed by Frank Lloyd Wright, who was an influential American architect in the first half of the 20^th century. Wright was largely ambivalent about dense cities. While he worked on some of the most important building in New York City, such as the Guggenheim Museum, he also envisioned that dense cities were obsolete given the advancement in technologies, most notably automobiles and telephones. His concept of Broadacre City would give each family one acre of land in the countryside. In 1935, Wright unveiled his detailed plan on a 12 ft x 12 ft model representing a community. It was ironically presented at New York’s Rockefeller Center, the antithesis of what Broadacre City called for.

Proposed during the Great Depression, Broadacre City reflected the social and economic uncertainty facing the country at the time. In his 1932 book The Disappearing City, Wright wrote of the “comfort” of wide spaces and that people of the future “will have all forms of production, distribution, self improvement, enjoyment, within a radius of a hundred and fifty miles of his home now easily and speedily available by means of his car or plane.”Wright’s Broadacre City called for pockets of community centers or small manufacturing centers, which were all necessities for society, but they would all be spread out. Roads would be the crucial artery linking the decentralized settlement. Inter-dispersed throughout the community would be single-family homes. Some of Wright’s ideas ultimately took shape in the form of the suburban sprawl observed in the United States after World War II, and for that reason Wright is aptly labeled as the prophet of suburbia. But it was the organized and planned nature of the development that separated Broadacre City and actual developments.

Even during the initial release in the 1930s, Wright faced much criticism for his Broadacre City layout proposal. Even before the days of environmentalism that have since followed, people back then called his plan largely wasteful. Today, many urban centers are seeking to reverse the effects of suburban sprawl that took effect in much of the country in the latter half of 20^th century. While Wright’s original model had called for “No traffic problems” thanks to the decentralization of the city, ironically one of the most negative consequence of the suburban sprawl has been traffic congestion and environmental degradation.

Sources:

• http://nextcity.org/daily/entry/frank-lloyd-wrights-utopian-dystopia
• Museum of Modern Art, Frank Lloyd Wright and the City: Density vs. Dispersal

Air Pollution in Mexico City

The papers Quantification of Local and Global Benefits from Air Pollution Control in Mexico City, Improving Air Quality in Megacities: Mexico City Case Study, and Air Quality Management in Mexico all looked into the issue of air pollution in the Mexico City Metropolitan Area, which increased its population 6-fold from 1950 to 2000, and presently is the largest urban agglomeration in the Western Hemisphere with population of more than 20 million While population affects many burgeoning cities in developing cities, it is especially problematic for Mexico City, which consumes more than 40 million liters of fuel daily, due to the surrounding topography, as mountains and frequent thermal inversions help to trap pollutants within the Valley of Mexico, which the capital sits. Since the mid-1980s, the government and citizens have recognized the serious concern of pollution, and regulations implemented in the 90s have helped to reduce the concentrations of various pollutants.

Currently transportation is the major source of pollution in the city, and one of the problems is that high-occupancy modes of transit have been declining as minibuses have gained popularity for their superior service and convenience, while existing formal high-occupancy systems, including the Metro, have not adequately adapted to the growing population trends. Antiquated fleet also contributes significantly to pollution, as the concentration of economic activities bring in much freight traffic. Regulation efforts have been put in to mitigate pollution. Vehicle inspection and maintenance programs, including no-driving days, began to be enforced, limiting the use of cars by one weekday starting in 1989. The policy has been remodeled to assign the ban depending on the vehicle’s emission levels. The country has also issued air quality standards comparable to those in United States. Natural gas began to replace fuel oil, and fuel quality has also been improved to reduce sulfur content and introduce unleaded gasoline. Furthermore, a low-interest loans to substitute old taxis have been implemented to improve fuel efficiency.

Despite the progresses, there are still potential pollution-mitigating projects with promising cost-benefit analysis from the standpoint of capital investment costs versus the decreased cost of health deteriorations. The project includes taxi fleet renovation, Metro expansion, hybrid bus introduction, liquid petroleum gas (LPG) leak prevention, and electricity cogeneration. The study finds that if all were implemented, the measures could save 100 lives, over 500,000 cases of minor restricted activity days (MRAD), and amount to $150 million (US) of local benefits per year. In particular, fuel savings would offset the cost of investment costs of taxi renovation, making this a particularly attractive economic investment. On the other hand, preventing LPG leaks would produce the greatest health benefit, compared to its size of investment costs, making this a high priority.

Sources:

• Instituto Nacional de Ecología: “Quantification of Local and Global Benefits from Air Pollution Control in Mexico City”
• L. Molina and M. Molina: “Improving Air Quality in Megacities: Mexico City Case Study”
• Adrián Fernández-Bremauntz: “Air Quality Management in Mexico”

Internal Combustion Engine

The engine of an automobile burns gasoline. The combustion produces expanding gases, which create the mechanical power used to move the vehicle. Generally speaking, the combustion can take place inside the engine, in the case of an internal combustion engine, or outside for an external combustion engine. Steam engine is an example of the latter. But internal combustion engine is more efficient, and is the type found in most automobiles.

The challenge of the engine is to sustain the transfer the energy from gasoline to kinetic energy of the vehicle. This repetitive mechanism is accomplished through the four-stroke combustion cycle, also known as the Otto cycle. Inside the cylinder of the engine is the piston, and its movement will direct the flow of the cycle. During the first step, known as the intake stroke, air and gasoline enters the engine, as the down movement of the piston opens up the intake valve, in order for the components to enter. Secondly, the upward movement of the piston then compresses this mixture of gasoline and gas. However, a mere compression does not start the reaction. During the third step, as the piston reaches the peak of its stroke, the spark plug gives off a spark that provides the activation energy necessary to finally ignite the gasoline. Finally, as the piston moves downward again, exhaust from the combustion leaves though a different value. While the movement of the piston is linear, it is helps to move the crankshaft, which is connected to the piston via the connecting rod. The rotational movement of the crankshaft is important, since it is then connected by gearing to the wheels of the automobile, which ultimately move in a rotational manner.

Various factors can go wrong in the engine, and tracing the steps of the Otto cycle reveals some of the reasons. To start off, the ingredients can be bad. The gasoline needs to have little impurity, such that it can burn. At the same time, the necessary amount of air is needed to supply enough oxygen for the combustion reaction. Once inside, lack of compression of spark also can be a source of problems. Compression can fail with leaky cylinders or valves not sealing properly, both of which prevents the pressure buildup from occurring. As for the spark, the wiring may be worn out or damaged.

Sources:

• http://auto.howstuffworks.com/engine.htm
• http://www.encyclopedia.com/topic/internal-combustion_engine.aspx

Risk Taking

Encountering uncertainty and managing risk is as fundamental as life itself. After all, aside from birth and death, little about life is certain. Understanding uncertainty and risk is relevant in various fields from study, from psychological counseling to investment undertaking. In an engineering context, it is important to understand the psychology behind decision making that affects the processes of capital projects, and their outcome as the projects come to fruition and enter usage.

It turns out that risk-seeking is somewhat hardwired in the brain. The neurological structure controls the actions of humans. Within the brain, the region of particular interest is the amygdala. Located within the temporal lobe of the brain, it is the center of emotion processing. It helps to configure emotional responses by storing memories, and recollections in turn help to determine the type of response elicited in new situations. Personality is largely determined by one’s reactions to various events, and not surprisingly, the amygdala plays a crucial role in shaping personalities. Scientific research has shown that people with damaged amygdala tend to exhibit a lack of fear and conscious. It also turns out that aside from neurology, evolution also plays an important role in risk. Historically men have been more risk-taking than women. Partial explanation comes from the historical fact that during human evolution, competition for social status and resources was predominantly focused among the males.

To the ordinary, risk takers are more inclined to engage in “dangerous” activities and gain more excitement from completing them. But research shows that they may suffer from boredom and lower job satisfaction. Constrained by the limits of society they reside in, they may also "have a hard time deriving meaning and purpose from everyday life." It is also consequential to recognize that more developed regions tend to foster more of these behaviors. For one, many of these risky activities, from skydiving to mountaineering, are not inexpensive hobbies. Secondly, for more developing societies, more efforts are needed to simply sustain some of the basic necessities, leaving out many opportunities to seek out additional challenges. As a result, a cultural irony develops in that as societies develop more and establish better and sustainably certain living conditions for the people, the more likely it is to indirectly foster uncertainty and risk-seeking.

Sources:

• http://biology.about.com/od/anatomy/p/Amygdala.htm
• http://www.breitbart.com/Big-Journalism/2012/05/17/Don-t-Fear-the-Amygdala-Progressives
• http://www.medicalnewstoday.com/releases/80914.php
• http://www.psychologytoday.com/articles/200910/risk