Trucks with semi-trailers are widely used for transportation of goods due their low operation cost, but inherent to these vehicles are some problems such as a poor maneuverability. To minimize the effects of this disadvantage, among other solutions, the incorporation of steerable axles in the semitrailers has been proposed. This paper presents a steering equation, and a fuzzy-logic controller for a semi-trailer automatic forced-steering system to minimize the off-tracking and the total swept path width, resulting in an improvement of vehicle´s maneuverability at low speeds. To accomplish this, the suggested control algorithm considers the articulation angle and parameters such as vehicle speed and direction. The system was tested on an instrumented experimental semi-trailer during various predetermined test maneuvers.

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Now a day, Mexico is looking the way to generate electricity by using renewable, clean and ecofriendly sources according the actual legal framework. This project is a meteorological portable station which will record either direction and speed of wind, light irradiation and environment air temperature in a data logger unit conformed by a microprocessor and a memory. The data recorded in the device will be mathematically analyzed and processed in a delimited period of time and plotted on different type of graphs or documents for to support feasibilities studies which could identify the power potential of photovoltaic energy and wind energy in the city of Altamira Tamaulipas. The main goal of this project is contribute with actual studies which will determine the feasibility of energy generation by using clean energy sources in the south part of our state promoting the development of energy power industry, mainly in the city of Altamira. Objectives: To build a portable meteorological station and to carry out a study of the measurement of the photovoltaic and wind energy exploitation potential in Tamaulipas, Altamira region, based on the data of the environmental variables measured and collected during a certain time, to determine the viability of generation electricity through wind and solar resource in this region. Methodology: In order to carry out the evaluation of the photovoltaic and wind energy potential measurement in Tamaulipas, Altamira region, a customized portable weather station module will be manufactured, to perform measurements of wind speed, wind direction measurements, temperature measurements, and irradiation measurements, at the site of interest. In addition, a system will be installed to register all the variables described in a micro SD memory and a communication system through a bluetooth module. This portable weather station will be installed, at the top of the library building of the Polytechnic University of Altamira. The exact geographical location is shown by means of Google Maps with a Latitude 22.462239 and longitude: -97.970186 (Google, 2018). Contribution: Provide information on the meteorological variables of our environment, adding a solar panel that demonstrates its viability. Implement an interface that allows constant monitoring and the different measurements made at the meteorological station, using sensors and microntrollers.

The concept of terrafomationis applied in general to establish a course of action in which hypothetically, it is possible to modify the natural conditions of a planet or moon to make it habitable for the human race, create an atmosphere with breathable air, potable water , fertile soils, climatic stability at a comfortable temperature; this process could take hundreds or thousands of years, as well as an important investment of resources and technology, however in the course of the time that we have inhabited this planet has deteriorated in many of its characteristics, to the point that it could be close the day in which the Earth is no longer apt to sustain the life of the human race. This article shows some of the challenges we should face so that the planet can recover its originalbenefits, as well as adapt our technology to be able to inhabit regions that we consider hostile today. Surely it would require a minor effort to completely transform a distant planet.

Man has dreamed of stars since their origins, they have inspired hundreds of great thinkers, artists and religious to understand why they are there, to understand how the celestial map changed night after night, imagining that we could reach them and find new and fantastic worlds, as well as unthinkable flora and fauna. Progressively, as science and technology advance, we can feel that those dreams are closer and closer to being realized. Today we are mainly focused on conquering Mars and although still distant, this idea starts to sound feasible. Using probes and terrestrial drones, we have been able to see the planet, decisive and transcendental steps, but they are the beginnings of a great sequence of necessary objectives before a human being can call the red planet "home". This article addresses the main challenges and obstacles that we would have to overcome in order to start an exodus to Mars, such as development of space vehicles, habitats, and environmental suits, generation of oxygen, water, food and energy, as well as essential genetic modifications.