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"The Fairphone is a modular handset designed with repairability and ethical sourcing of its materials as headline features. It sold 60,000 units. Amazingly, for what sounds like a nerd-phone, almost half of those buyers had never owned a smartphone before. Now the Fairphone 2 is launching, and with a totally-new, in-house design. The new phone is even easier to repair, and because it was wholly designed by the FairPhone team, its supply chain is even more responsible than ever. The Fairphone is thicker than the latest iPhone or Samsung flagship, but that's the point. Instead of packing everything into a tiny case and keeping it there with glue, the Fairphone is designed to be taken apart. The lightweight magnesium frame supports modules that can be easily replaced by the user. "We have designed it with an aim to last three to five years, looking at making it robust and modular-for repairability," says Fairphone's chief communications officer, Tessa Wernink. "Obviously how long it lasts depends quite heavily on the user, so what we as a company are doing is offering an ecosystem around the phone that supports long-lasting use, first-hand or second-hand." Inside the case (itself one of several options) you'll find the core unit, containing all the chips and radios; a replaceable battery pack; a display that can be snapped off and replaced without any tools (not even a screwdriver); a receiver unit, which contains the front camera, sensors; the headset connector and microphones; a speaker/vibrator unit; and a camera module. These modules are designed to balance manufacturing complexity with repairability. For instance, the display comes as a standalone unit, but less-vulnerable components are bundled into one module. The camera, which people are most likely to upgrade as better versions become available, is also housed in its own module. That way you don't need to toss out your whole phone just to get a better camera. "In fact, the motto from the maker mo

"In order to help reduce the gap between industrialized countries and those in the emerging economy, UNESCO has decided to adopt an Open Access Policy for its publications by making use of a new dimension of knowledge sharing - Open Access. Open Access means free access to scientific information and unrestricted use of electronic data for everyone. With Open Access, expensive prices and copyrights will no longer be obstacles to the dissemination of knowledge. Everyone is free to add information, modify contents, translate texts into other languages, and disseminate an entire electronic publication."

"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

"Generating electricity is not only inefficient, it also makes pedal power less sustainable, less robust and more costly. To begin with, batteries have to be manufactured, and they have to be replaced regularly. This requires energy, which can completely negate the ecological advantage of pedal power. According to this research paper (pdf), the embodied energy of a 150Wh lead-acid battery (like the one offered with the Windstream pedal power generator) is at least 37,500 Wh, which equals 250 full charges of the battery (more sources: 1/2). In other words: if you can deliver 75 watts of power to the battery, you have to pedal for 500 hours in order to generate the energy that was needed to manufacture the battery. Because the life expectancy of a lead-acid battery can be as low as 300 discharge/charge cycles (sources: 1/2), you are basically pedalling to produce the energy required to manufacture the battery. If you also factor in the embodied energy of other electronics and parts, the ecological advantage of a pedal powered generator connected to a battery becomes rather doubtful. It might costs more energy than it delivers."

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"A discovery engine of websites, mobile apps, desktop programs, and electronic products for teaching and learning. First time here?"

"Imagine you could use any kind of small head difference in a river or canal. The power those drops contain might surprise you. We created a technology that can make use of all these small waterfalls or rapids in a way that's safe for the environment. Gone are the days that communities had to choose between having power or fish to eat. Our robust and fish friendly vortex turbiness will generate energy 24/7 at an incredibly low cost of energy. That way you can have a project with high return on investment that improves the world just that little bit. Now, if you look at a river or canal, you'll notice that it's full of these small cascades, that's how nature builds rivers. We have created a distributed turbine system that can combines a large amount of turbines into one big virtual hydropower powerplant. These virtual hydropower plants can be as large as 10MW in power output. That's the power production of a small city! We can do this because our civil structures are designed to be easy to install, and the electronics and robust power take-offs are designed to keep working with minimal maintenance. The energy produced can be directly connected to your appliances or machinery, and at the same time connected to the national distribution grid, so you can inject the unused power to it, maximizing the revenue through a net billing connection."

"La que sigue, es una historia que me acercó Juan Pablo Paz -uno de los científicos más prestigiosos que tiene la Argentina- y que está dando vuelta hace un tiempo en los medios académicos (y no académicos también). En todo caso, después de leerla verá que ni siquiera importa si es cierta, aunque los físicos aseguran que sí. Lo que seguro vale la pena es discutir su contenido. Y pensar. Muchas veces, en un colegio o en alguna facultad, un alumno tiene una idea distinta, una idea que el profesor no contempló, no pensó. Una idea: ni más ni menos que eso. Y la reacción del docente no siempre es la esperable: pensar con el alumno, dejarse desafiar por alguien que piensa diferente, que propone un ángulo diferente. Este capítulo entonces, está dedicado a la reflexión a la que invita la siguiente historia: Sir Ernest Rutherford, presidente de la Sociedad Real Británica y Premio Nobel de Química en 1908, contaba la siguiente anécdota: "Hace algún tiempo, recibí la llamada de un colega. Estaba a punto de ponerle un cero a un estudiante por la respuesta que había dado en un problema de física, pese a que éste afirmaba convencidísimo que su respuesta era absolutamente acertada. "Profesores y estudiantes acordaron pedir arbitraje de alguien imparcial y fui elegido yo. "Leí la pregunta del examen y decía: ¿Qué haría usted para determinar la altura de un edificio con la ayuda de un barómetro? "El estudiante había respondido: 'Lleve el barómetro a la azotea del edificio y átale una cuerda muy larga. Descuélguelo hasta la base del edificio, marque y mida. La longitud de la cuerda es igual a la longitud del edificio'. "Realmente, el estudiante había planteado un serio problema con la resolución del ejercicio, porque había respondido a la pregunta, correcta y completamente. "Por otro lado, si se le concedía la máxima puntuación, podría alterar el promedio de su año de estudios, obtener una nota más alta y as�

"Todo el mundo habla de Arduino. De su sencillez de programación, de los numerosos tutoriales que hay en la red sobre él. De lo fácil que es meterse en el mundo DIY si lo utilizas. ¡Hasta un niño podría programarlo!, dicen. Pero, ¿Qué Arduino elegir? El problema es que al entrar a la página oficial de Arduino, nos encontramos con 21 placas, 8 shields, 2 kits y 4 accesorios. Demasiada información para alguien que está empezando. Lo primero es pensar para qué tipo de proyectos se va a utilizar: 1) Necesidad de conexión Wifi 2) Tensión de alimentación 3) Tamaño 4) Número de entradas y salidas 5) Tensiones de LOW y HIGH" Más detalles en el enlace...

"Todo el mundo habla de Arduino. De su sencillez de programación, de los numerosos tutoriales que hay en la red sobre él. De lo fácil que es meterse en el mundo DIY si lo utilizas. ¡Hasta un niño podría programarlo!, dicen. Pero, ¿Qué Arduino elegir? El problema es que al entrar a la página oficial de Arduino, nos encontramos con 21 placas, 8 shields, 2 kits y 4 accesorios. Demasiada información para alguien que está empezando. Lo primero es pensar para qué tipo de proyectos se va a utilizar: 1) Necesidad de conexión Wifi 2) Tensión de alimentación 3) Tamaño 4) Número de entradas y salidas 5) Tensiones de LOW y HIGH" Más detalles en el enlace...

Playlist https://www.youtube.com/watch?v=RRpUMjMHU6U&list=PLpOqH6AE0tNgrhG4Lca75PMoE-yHrwcDq VIDEO 1 TRAILER https://www.youtube.com/watch?v=RRpUMjMHU6U VIDEO 2 INTRODUCCIÓN A LA PROGRAMACIÓN VIDEO 3 HOLA MUNDO VIDEO 4 CONOCIMIENTOS BÁSICOS DE ELECTRÓNICA VIDEO 5 BOTONES VIDEO 6 VOLTAJES ANALÓGICOS Y PWM VIDEO 7 COMUNICACIÓN SERIAL VIDEO 8 TEMPERATURA VIDEO 9 DEBOUNCE VIDEO 10 MANEJO DE DISPLAYS DE 7 SEGMENTOS VIDEO 11 PING A SENSOR ULTRASONICO VIDEO 12 MANEJO DE SERVOMOTORES VIDEO 13 BOOT O STANDALONE VIDEO 14 TECLADO MATRICIAL VIDEO 15 MANEJO DE RELÉS VIDEO 16 ENCENDER UNA BOMBILLA CON UN SENSOR PIR https://www.youtube.com/channel/UCLXRGxAzeaLDGaOphqapzmg channel codigofacilito

"En Agbogbloshie, un barrio suburbano de la capital de Ghana se ubica el mayor vertedero de desechos electrónicos de África Occidental. Se trata de una de las áreas más contaminadas por metales tóxicos del continente africano. Para muchos ghaneses es fuente de subsistencia; pero lo que les da de comer, los acaba matando."

"Hace tiempo atrás hicimos un top de Los 10 mejores Software de diseño PCB en el que hablamos muy a detalle de diversas aplicaciones que nos permitían dar vida a nuestros proyectos electrónicos, en esa oportunidad no conocíamos a LibrePCB y sinceramente creo que es un crimen que no haya estado incorporado en dicho listado, pues para tratar de redimirnos traemos una review de este grandioso software de diseño PCB gratuito y libre."