Transport
The transportation (tb. transportation) is a set of processes whose purpose is movement and communication. In order to carry out these processes, different means of transport (car, truck, plane, etc.) that circulate by certain means that can be land, air, sea, etc.
Transport System
Conveyor system components
‘’”In order to carry out the transport action, several elements are required, which interacting with each other, allow it to be carried out:
An infrastructure in which the activity is physically carried out, for example roads for road transport, pipelines for the transport of hydrocarbons, cables for the transport of electricity, channels for navigation on the continent (inland navigation), aerodromes for air transportation, etc. vehicle: instrument that allows the rapid transfer of people. Examples of vehicles are the bicycle, the motorcycle, the car, the bus, the boat, the plane, etc.’’.”
In order to carry out the transport action, several elements are required, which interacting with each other, allow it to be carried out:
- One infrastructure in which the activity is carried physically, for example the roads for road transport, ducts for the transport of hydrocarbons, cables for the transport of electricity, channels for the navigation on the continent (inland navigation), airfields for air transportation, etc.
- vehicle: instrument that allows the rapid transfer of people. Examples of vehicles are bicycle, motorcycle, car, bus, boat, airplane, etc.
- A operator transport, reference to the person who drives or guides the vehicle
- A few services that allow the activity to be carried out safely, as lights.
The transportation system requires several elements, which interact with each other, for the practice of transportation and its benefits:
- Infrastructure, which is the physical part of the conditions required to implement transport, i.e. roads and roads are required for urban, provincial, regional and international land transport, airports and air routes are required for air transport, and also channels and navigation routes are required for shipping either by sea or by rivers and lakes. Another part of the infrastructure is the stops and traffic lights in urban transport, in air transport are the control towers and the radar, and in the naval ones are the ports and the radars.
- The vehicle or mobile is the instrument that allows the transfer of people, things or objects from one place to another.
- The transport operator is the person in charge of driving the vehicle or mobile, in which people, things or objects are to be moved.
- Rules or laws, It is the main part of the transport system, is the one that dictates how to move from one place to another, it is also the one that regulates and regulates the operation of all applicants and offerers of the transport service.
Supply and demand
Transportation engineers use these concepts when conceiving, planning, designing, and operating a transportation system. For an efficient system, it is desirable that the demand make maximum use of the existing infrastructure. Demand should only rarely exceed supply.
One of the most illustrative examples is that of the tracks. The offer for this case is the roads and the vehicles demand them. When few vehicles use the road, it is said that the infrastructure is providing a good service, but it is inefficient. When many vehicles use the road in a functional way, they will operate the infrastructure efficiently, but the service it provides to users is no longer so good. When too many vehicles demand the roads, congestion forms and this is considered unacceptable.
Classification
Transportation can be classified in several ways simultaneously. For example, regarding the type of trip, the type of element transported or access. For example, passenger transport is generally classified into public transport and private transport.
Passenger transportation, cargo transportation
Cargo transportation is the discipline that studies the best way to transport goods from one place to another. Associated with cargo transportation is Logistics, which consists of placing important products at the precise moment and at the desired destination. The biggest difference from passenger transport is that travel time and comfort are counted for it.
Urban transport, interurban transport
This classification is very important due to the differences that the two types of trips imply. While urban trips are short, very frequent, and recurring, intercity trips are long, less frequent, and recurring.
Public transport, private transport
Public transport is that in which travelers share the means of transport and that is available to the general public. It includes various means such as buses, trolleybuses, trams, trains, suburban railways or ferries. In interregional transport, air transport and high-speed train also coexist.
Public transport differs from private transport basically in that:
- in private transport the user can select the route
- in private transport the user can select the time of departure, while in public transport the user must be confined to the hours
- in private transport the user can infer on the speed of the trip, while in public transport the travel time is given by stops, schedules and operating speed.
- in public transport the user receives a service in exchange for a payment, technically known as fare, while in private transport, the user operates his vehicle and takes care of its costs.
The most representative of the modes of private transportation is the automobile. However, walking and cycling are also within this classification. The taxi, despite being a service open to the public, is classified as private transport.
School transportation
School transport or student transport carries out trips for children and adolescents from their places of residence to schools and vice versa. Despite the fact that many of these trips are carried out in private means of transport, it is also very frequent that they are carried out collectively in buses and special caravans for this purpose.
In the United States and other countries, it is common for buses to be dedicated to take schoolchildren from their place of residence to school. US regulations require that an adult caretaker, other than the driver, ride the bus and that buses are no older than 16 years of age.
In other countries such as Germany or Finland, students travel alone in the city's public transport vehicles. Normally, students receive a card that allows them unlimited use of these services for the entire semester, at a very low cost (subsidized).
In the case of a South American country, Chile has a deferred rate for students that can be opted for by presenting a School Pass at the time of canceling the ticket. This, in turn, allows you to opt for different fares, with Primary Education being a free ticket and Secondary Education as well as Higher Education a percentage of the adult ticket (50% in regions and 33% in Santiago). In Davis, the United States, more than 40% of boys and girls ride bicycles to school.
Means of transportation
They are the physical means through which the vehicles that are used for the transfer of people and goods transit. Thus, the following means can be distinguished: terrestrial, aerial and aquatic
Modes of transportation
The modes of transport are the modality or type of infrastructure necessary to carry out the journeys. They include pedestrians, bicycles, cars, buses, trucks, railways, fluvial and maritime transport (ships, canals and ports), air transport (airplanes, airports and air traffic control), including the union of several or all three types of transport. We speak of modal split to describe, in a given area, how trips are distributed among the different modes that use the infrastructure (similar or different: railways and highways in the urban sprawl).
According to the modes of transport used, transport is classified or categorized into:
- Road transport: pedestrians, bicycles, cars and other vehicles without railings.
- Rail transport: rolling material on railroad tracks.
- Transport by waterways: shipping and river transport. For water the boat is the best known.
- Air transportation: aircraft and airports.
- Combined transport: several modes of transport are used and the goods are transferred from vehicle to vehicle. This mode of transport has been developed giving rise to intermodal transport or multimodal transport, in which the goods are grouped in "high load units", such as the container, which allow transport through different pathways without "loading break".
- Vertical transport: lifts and lifts.
- Pipe transport: pipelines and pipelines, in which fluids are driven through pipes through pumping or compression stations.
Similarly, a distinction can be made between public transport and private transport depending on the ownership of the means of transport used.
It may also be interesting to distinguish between the transport of goods and the transport of passengers.
Multimodal Integration (of passenger transport)
The integration between more than two modes of transport is multimodal integration, said integration can be physical, operational or tariff. For example, integration between the bus and a metro or tram system.
Intermodal Integration (passenger transport)
The integration between routes of a single mode of transport, said integration can be physical, operational or fare. For example, integration between two routes where they benefit the passenger with a lower rate for using them in a route.
Transportation modelling
Transport modeling or transport modeling allows planning future and current situations of urban transport. The concept of "model" must be understood as a representation, necessarily simplified, of any phenomenon, process, institution and, in general, of any "system". It is a very important tool for the planner, since it allows simulating various action and temporary scenarios that help to evaluate alternatives and carry out a diagnosis of the future.
The classic modeling scheme is that of four stages or four steps.
- Step 1: Travel generation models to evaluate travel produced and attracted by each transport zone in different scenarios.
- Step 2: Distribution modelsto estimate future origin-destination matrices (O/D).
- Step 3: modal selection models, to determine the capture of each mode between the different O/D relationships, for the motives that are calibrated.
- Step 4: Road Selection Models or Allocation which allows to determine the chosen paths or routes for each relationship and the load by sections for road lines or networks in the different time periods analyzed.
Sometimes, depending on the available data and the type of analysis desired, the generation model can be dispensed with, leaving it in three stages and obtaining only the distribution model. In really competitive highway corridors without public transport, it is common to assume that there is no modal transfer and only the distribution model (or a growth model) and the allocation model only are used.
Other types of models can also be mentioned, such as those of land use that allow interrelated and complex analyzes between activity in the territory and transport.
Design of transport networks
Networks are designed considering three aspects: geometry, resistance and capacity. In practice, transportation design focuses on taking geometric designs and defining their width, number of lanes, tracks, or diameter. Your product is taken by the specialist in pavements, rails, bridges or pipelines and converted into thicknesses of roadway, ballast, beams or pipe walls. The transportation engineer is also responsible for defining the operation of the system considering time.
The main methods for network design include the four-stage method, the use of queuing theory, simulation, and what might be called empirical coefficient methods.
Four-stage method
In this transport modeling method, the "trip generation", or number of people or amount of cargo produced by an area, is calculated separately; the "travel distribution" of trips, which allows estimating the number of trips or amount of cargo between each zone of origin and destination; the "modal split", that is, the calculation of the number of trips or amount of cargo that the different modes of transport will use and its conversion into number of vehicles; and, finally, the "assignment", or the definition of which segments of the network or routes will be used by each of the vehicles.
This process is carried out using the density and location of the population or current load to verify that the volumes predicted by the method are in accordance with reality. Finally, future population estimates are used to recalculate the number of vehicles on each arc of the network that will be used for design. It is mainly used to design transportation and is required by law in many urban areas.
Queuing theory method
Uses statistics and certain assumptions about the service process. It makes it possible to estimate, based on customer arrival rates (whether vehicles or people) and the service speed of each service channel, the length of the queue and the average service time. The customer arrival rate must be analyzed to find out not only its intensity in number of customers per hour, but also its distribution over time. It has been found, experimentally, that the Poisson distribution and the geometric distributions reflect well the random arrival of customers and the arrival of clustered customers, respectively. It is mainly used to estimate the number of toll booths, pumps at fuel stations, service posts at ports and airports, and the number of ATMs or customer service lines required in an establishment. Queuing theory is based on stochastic processes...
Transport simulation methods
There are two main types of computer simulations used in transportation engineering: macrosimulations and microsimulations.
Macrosimulations use equations that reflect general parameters of vehicle flow, such as speed, density, and flow. Many of the ideas behind these equations are taken from analysis of the flow of liquids or gases or from empirically found relationships between these quantities and their derivatives.
The second ones simulate each vehicle or person individually and make use of equations that describe the behavior of these vehicles or people when they follow another (vehicle tracking equations) or when they circulate without impediments.
Coefficient Methods
They use theoretical-type equations but, in general, they start from measurements that indicate the capacity of a network under ideal conditions. This capacity normally decreases as the network or circumstances move away from that ideal.
The methods provide coefficients less than unity, by which the "ideal" of the network to find the capacity under the given conditions. and that more things
Transportation and communications
Transportation and communication are both substitutes and complements. Although the progress of communications is important and allows information to be transmitted by telegraph, telephone, fax or email, personal contact has its own characteristics that cannot be replaced.
The growth of transportation would be impossible without communication, vital for advanced transportation systems (train control, air traffic control, road traffic control, etc.). There is, however, no proven relationship between the growth of these two systems. The best predictor of the growth of a transportation system is the growth of the gross domestic product (GDP) of an area. It is also relatively easy to find GDP predictions. The use of historical series to predict the future growth of the transport system can lead to serious errors (problem of "suboptimization" or of fragmentary analysis of a system).
Theory of Mobility applied to Transport
Transport mobility theory is a social theory pioneered in Lancaster, United Kingdom by sociologist John Urry. His academic position suggests that the globalized world is characterized by high mobility that connects people through transport, merchandise, signs and geographic spaces. Geographic spaces are integrated through signs that are their own and that can be exchanged semiotically. These signs not only confer value to the product consumed but are connected to a cultural matrix that offers the consumer tourists a diversity of landscapes. The theory of mobility suggests that there are different ways of moving that condition the subject and his conception of the environment. Urry argues that modern tourists and travelers move outside their homes with the ultimate goal of possessing what they want to see. The tourist gaze (tourist-gaze) must be understood as a social institution centered on the need to possess but also to accept the gaze of the "Other".
In recent years, some authors such as Maximiliano Korstanje and Rodanthi Tzanelli have established a critical approach to mobility theory arguing that beyond the paradigm, real mobility in the global north differs substantially from that of the south. In this In this sense, the theory of mobility finds certain limitations to explain the reality of underdeveloped countries in the global south, where mobility is not the rule but the exception. In this sense, Raoul Bianchi offers an explanation of the different asymmetries and class inequalities that globalization opens up on the planet.
For his part, Philip Vannini argues that the sociology of mobility should pay particular attention to means of transport as well as their socio-cultural impacts on daily life and culture itself. Global capitalism creates specific discursivities that legitimize the exclusion of certain actors from the productive system. To this end, mobility must be understood as a sign of status for those groups that are empowered to travel, while others remain immobilized without any possibility of doing so.
Transportation, activities and land use
Transportation and land use are directly related. Depending on the use of the land, specific activities are generated that do not necessarily coincide with the place of residence of those who develop them, in which case they must be transferred. A day can be divided between the time spent on activities and the time spent traveling to and from the place where those activities take place. It is said that transportation is "an indirect demand", since it lacks an end in itself, but it is necessary to carry out the activities at the destination site.
Grouping a variety of activities within the same land area minimizes the need for transportation. On the contrary, the organization by zones of exclusive activities increases it. However, there are economies of scale when grouping activities, which prevents an organization of activities by completely heterogeneous zones.
Transportation and land use also interact in another way, since transport services consume land, just like cities. An efficient transportation system can minimize land use. However, this saving must be weighed against the cost; an efficient transport system in a large city can be extremely expensive.
Transport, energy and the environment
Transportation is an important consumer of energy, it can be obtained by burning fuels, until not long ago mostly fossil fuels in combustion engines. In the combustion process polluting gaseous emissions are generated (CO2, CO, NOx, SOx and others, such as particles) whose harmfulness depends on the source of energy used.
EVs are often held to be "clean," as are those that use hydrogen fuel cells. But really, it depends on the source from which the electricity comes. If they use electricity produced in plants powered by fossil fuels, the pollution is more localized than with combustion cars, since carbon capture and storage techniques can be applied. If renewable sources (renewable electricity) are used, this emission problem does not exist.
As fossil fuels are expected to run out by 2050, global transportation faces the challenge of completely changing its systems in just under five decades. It is expected that hydrogen vehicles will be the most economical, if current technologies are extrapolated, with which we will have to learn to produce it by other methods than the highly polluting one used today (treatment of natural gas with steam), which generates huge amounts of carbon dioxide, if we want its use to not further contribute to global warming.
During the last few years, vehicles have been getting cleaner, as a consequence of stricter environmental regulations and the incorporation of better technologies (catalytic converters, etc.), and, above all, better use of fuel. However, this situation has been more than offset by the rise in both the number of vehicles and the increasing annual use of each vehicle, which determines that cities with more than 1,000,000 inhabitants present problems with excessive air pollution rates, affecting the health of the population.
In 2009, NASA promoted the so-called Green Flight Challenge, a contest that awards half a million dollars to the most original and efficient project. More than half a dozen projects have been submitted so far. The initiative is developed in cooperation with the following North American institutions: Department of Agriculture and Energy, the Environmental Protection Agency, the National Science Foundation and the National Institute of Commerce of Standards and Technology, together with the Office of Patents and Trademarks. Some of these projects are:
Cri-Cri An all-electric, French-made aerobatic airplane. It is powered by four engines and has a flight range of 30 minutes at a cruising speed of 100 km/h.
SugarVolt Hybrid model designed by Boeing. It works with a combination of kerosene (propeller) turbines, which are what make it take off. But, once in the air, requiring less energy, it flies with an electric motor.
Skyhawk 172 The aeronautical firm Cessna plans to have it ready by the end of 2011. The small plane will have only two seats, but even so it is estimated to be one of the most used due to its resemblance to a previous model, which has been included improvements.
The Superboeing Not all green planes will be electric. This is a Boeing supersonic prototype that runs on high-performance fuel, and is being designed in collaboration with NASA. In addition, in terms of the aerial means, another handicap to take into account arises. At present, the innovations that have been made in airplanes limit commercial flights too much. In other words, the market is close. The vast majority are private jets with few seats that do not allow mass passenger transport, therefore, the initial problem of making a low-pollution option feasible for the general public; in this case it is impossible at the moment.
The transport and distribution of energy by means of transport have caused multiple accidents that have seriously affected people, facilities and the environment. The transport of energy varies depending on the type of energy to be transported.
- The transport of coal: it is carried out mainly by road and rail, and lately river transport is increasing.
- The transport of oil: it is carried out mainly by pipelines and oil tankers, and the consumer through tankers.
- The transport of electrical energy: it is carried out through the electrical networks, which distribute the current from the primary transformative stations to the consumer and sometimes in reverse form (V2G).
The environment also causes significant impacts on the energy system; It is worth noting the effect of earthquakes, hurricanes, storms, sudden variations in temperature, etc.