lunes, 31 de enero de 2011
sábado, 29 de enero de 2011
: Acércate y mira
: Acércate y mira: "Si se mira muy de cerca, todo es bello. Macro Kingdom es un trabajo de Clemens Wirth, estudiante de arte multimedia en la ciudad austriaca d..."
viernes, 28 de enero de 2011
Milan and EvoBus present first hydrogen bus in Milan
Milan and EvoBus present first hydrogen bus in Milan
Elio Catania, president of ATM – the company providing for public transportation in Milan – and Roman Biondi, president of EvoBus – the company responsible for distribution of Mercedes-Benz and Setra buses within the DaimlerChrysler Group - presented to the press the first hydrogen-powered bus in Milan. The presentation and demonstration tour in the city was also attended by the director of H2IT Marieke Reijalt and the secretary general of FAST Alberto Pieri.
Within this project ATM and the Lombardy Region have committed to supply the city of Milan with a fleet of 3 hydrogen buses starting from 2011. “ATM between 2008 and 2011 is going to invest 640 million in new trains, buses and trams: a huge effort of renewal to maintain the average life of our vehicles among the lowest in Italy” – said Elio Catania – “In the last two years we have invested 506 million euros in total”.
The bus presented today is a Citaro FuelCell Hybrid produced by Mercedes-Benz. Thanks to the hybrid traction and its sophisticated management system, the consumption of hydrogen in the Citaro FuelCell Hybrid is set to decrease substantially compared to previous fuel cell buses. The fuel cell generates electricity which is stored in the battery system. This, in turn, supplies power to the traction motors and the other vehicle components. During braking or no-load operation, the traction motors recuperate energy which is also fed into the battery system.
The fuel cells used in this bus offer a power generation efficiency of 51-58% compared to 38-43% of the previous generation. Thanks to this, it was possible to reduce from 9 to 7 the number of hydrogen tanks, now capable of storing 35 kg of hydrogen at 350 bar - enough to ensure a range of 250 km. The heat generated by the reaction is used by the heating system of the vehicle. The two fuel cell stacks generate 120 kW of power. The fuel cells are supported by lithium-ion batteries with a weight of 330 kg and an output of 250 kW.
“It has been many years for Mercedes-Benz investing in fuel cell technologies” – said President of EvoBus Roman Biondi – “The first project started in 2002 with 40 vehicles operating in 12 cities worldwide for more than 2 years. This project has allowed the company to accumulate operating experience, to further develop the components and reduce costs”.
¿Cómo aumentar la potencia de los aerogeneradores?
La energía eólica parte con ventaja ante sus competidoras renovables. Por este motivo, la presencia y el tamaño de las turbinas es cada vez mayor. Los nuevos aerogeneradores necesitan funcionar a muy altas potencias y superar los actuales límites electrónicos y estructurales. Ahora, una tesis, defendida en la Universidad del País Vasco (UPV/EHU), aporta una serie de soluciones para que las turbinas puedan cumplir dichos requisitos.
La base para acceder a mayores niveles de potencia y eficiencia de las turbinas de los aerogeneradores está en un mecanismo de accionamiento directo (que no necesita una multiplicadora de velocidad) acompañado de un convertidor de toda la potencia. Así lo indica la tesis de Eider Robles, Grid connection and control of multipole synchronous wind turbines, que muestra como este mecanismo es, a su vez, muy exigente en cuanto a las propiedades de los elementos que deben formar el sistema.
En lo que al tipo de generador se refiere, la tesis determina como el más apropiado el generador síncrono de imanes permanentes (GSIP) con rotor externo. El GSIP es un tipo de generador que no necesita de anillos rozantes para transmitir la electricidad. Así, el movimiento giratorio del rotor no provoca fricción, se reducen las pérdidas en el cobre, y la necesidad de mantenimiento disminuye. Además, el hecho de que el rotor sea externo permite acoplar las palas directamente, lo cual permitiría minimizar el peso de la estructura mecánica.
Por otra parte, la tesis propone una alternativa para trabajar a una mayor potencia. En la actualidad, los dispositivos semiconductores tienen limitaciones de tensión y corriente, por lo que la inclusión de convertidores de toda la potencia (tal y como plantea Robles como base) sería imposible en aerogeneradores de varios megavatios.
La ingeniera propone utilizar convertidores multinivel, ya que estos posibilitan el uso en serie de los semiconductores, y en este caso sí sería factible superar las limitaciones y obtener un mayor voltaje. Para una calidad aún mayor, la investigadora ha propuesto añadir un sistema que contrarresta las perturbaciones externas como las variaciones de viento. Se trata de los controles feedforward o de prealimentación, que tienen la capacidad de reaccionar a los cambios en su entorno.
Los detectores de secuencia positiva, la principal aportación
Entre las exigencias que debe cumplir un sistema de potencia conectado a red, cabe destacar las tareas de control para contrastar los desequilibrios y las distorsiones que ocurren en la tensión de red. Este control es, además, un requisito indispensable para cumplir las nuevas normativas, que exigen un funcionamiento continuo de las turbinas, independientemente de los desequilibrios, distorsiones y demás perturbaciones.
Para obtener la estabilidad y una mayor eficiencia en la conexión a red, el principal objetivo de esta tesis era, precisamente, el diseño de métodos robustos de detección de secuencia positiva. La tensión de red se compone de secuencia positiva (la parte útil), pero también de otros componentes provocados por los desequilibrios y distorsiones. Los detectores, compuestos por secuencias algorítmicas, aíslan la secuencia positiva.
Robles ha realizado una revisión exhaustiva de los actuales detectores de secuencia positiva y de las técnicas de sincronización. Según se explica en la tesis, el principal inconveniente encontrado en este análisis es que, en general, dichos detectores están especializados en un tipo de perturbación u otro, pero no en todos simultáneamente.
Finalmente, la ingeniera ha resuelto este problema con el uso de cuatro detectores de secuencia positiva, los cuales se basan en unos filtros denominados MAF (filtros de promediado local, del inglés Moving Average Filters). Estos detectores muestran un tiempo de asentamiento rápido y constante en presencia de cualquier tipo de perturbación, incluso si diferentes perturbaciones ocurren simultáneamente.
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Sobre la autora
Eider Robles Sestafe (Bilbao, 1980) es ingeniera automática y electrónica por la Universidad de Deusto. Ha realizado la tesis bajo la dirección de José Luis Martín González (profesor del Departamento de Electrónica y Telecomunicaciones de la Escuela Técnica Superior de Ingeniería de Bilbao, UPV/EHU) y Josep Pou Félix (profesor de Ingeniería Electrónica de la Universidad Politécnica de Cataluña). En la actualidad, Robles es investigadora de Tecnalia, centro en el que ha realizado la tesis, dentro del Grupo de Investigación sobre Conversión de Energía. Tanto la tesis como el trabajo del grupo han sido realizados en colaboración con la Universidad Politécnica de Cataluña y la Escuela Técnica Superior de Ingeniería de la UPV/EHU.
Fuente: http://www.agenciasinc.es/esl/Noticias/Como-aumentar-la-potencia-de-los-aerogeneradores
viernes, 21 de enero de 2011
RetBus a Barcelona
Poder obtener mejores resultados de explotación con los mismos recursos, pero gestionados en su explotación de forma coordinada, medida y calculada, nos genera:
- conocer donde estamos
- saber donde debemos mejorar
- conocer si mejoramos
Green Car Congress: 12 natural gas Ford Transit Taxis to enter service in Chicago
Green Car Congress: 12 natural gas Ford Transit Taxis to enter service in Chicago
Taxi Medallion Management in Chicago has purchased 12 Ford Transit Connect Taxis running on compressed natural gas (CNG) for its fleet. The cabs will be affiliated with Yellow Cab Chicago and bear the company’s logo and color.
The purchase is part of the company’s goal of reducing emissions by 25%, said Michael Levine, CEO of Taxi Medallion Management. According to the US Environmental Protection Agency (EPA), CNG is less expensive and burns cleaner than gasoline, resulting in 30 to 40% less greenhouse gas emissions.
The Ford dealership, Packey Webb Ford, of Downers Grove, Ill., will deliver the taxi units to Taxi Medallion Management with an engine preparation package for conversion to CNG.
Since introduced as a production vehicle last year, Transit Connect Taxi is gaining interest from taxi operators around the country. The first taxi was delivered to Boston Cab Dispatch in December 2010.
The Transit Connect Taxi package adds comfort for the passenger with a
1) repositioned second-row seat for more legroom,
2) grab handles and a
3) rear ventilation system with passenger controls.
For the driver, in addition to the
a) comfortable driving environment, new features include
b) rear view camera and back-up sensor,
c) heavy-duty battery and wiring block connector to power upfitted accessories. The taxis have a 39-foot turning radius.
The standard Ford Transit Connect—2010 North American Truck of the Year—features a 2.0-liter I-4 engine that gets EPA-estimated 21 mpg city and 26 mpg highway, an estimated 30% improvement in fuel economy compared with traditional taxis.
In addition to CNG, Transit Connect Taxi is available with an engine preparation package for conversion to liquefied propane gas (LPG).
During its first full year of production, 27,405 Transit Connect vehicles were sold in the United States.
miércoles, 12 de enero de 2011
martes, 11 de enero de 2011
lunes, 10 de enero de 2011
High-Power Supercapacitor Electrodes from Single-Walled Carbon Nanohorn/Nanotube Composite - ACS Nano (ACS Publications)
High-Power Supercapacitor Electrodes from Single-Walled Carbon Nanohorn/Nanotube Composite - ACS Nano (ACS Publications): "High-Power Supercapacitor Electrodes from Single-Walled Carbon Nanohorn/Nanotube Composite"
domingo, 9 de enero de 2011
sábado, 8 de enero de 2011
TMC, Hino to offer fuel-cell bus for Tokyo Airport routes - Automotive Business Review
TMC, Hino to offer fuel-cell bus for Tokyo Airport routes - Automotive Business Review: "TMC, Hino to offer fuel-cell bus for Tokyo Airport routes"
Hydrogen Bus Lets Lab Visitors Glimpse Future
Hydrogen Facts
- Hydrogen can be made from a wide variety of domestic, renewable resources such as solar, wind, biomass, and geothermal energy.
- Enough hydrogen is produced in the U.S. every year to fuel 34 million fuel cell vehicles. Right now the hydrogen is used primarily for commercial purposes such as cleaning up gasoline and processing certain foods.
- Hydrogen is neither more nor less hazardous than more common fuels like natural gas, propane, or gasoline.
- Compared to conventional gasoline engines, hydrogen powered engines have very low criteria emissions and near-zero greenhouse gas emissions when the hydrogen is produced from low carbon or renewable resources.
- Hydrogen is up to 25 percent more efficient than gasoline in conventional spark ignition engines and around 100 percent more efficient in fuel cell power trains.
- Only modest design modifications to standard combustion engine technology are needed, so the engine technology is familiar to mechanics and fleet personnel.
- With very few cost and technical issues limiting commercialization and deployment, H2ICE vehicles can help create the demand needed to support the build out of a hydrogen infrastructure.
Hydrogen Buses
Hydrogen Buses
The history of hydrogen buses is murky at best. What is known is that an engineer from Germany, Rudolf Erren started converting internal combustion engines (ICE) in buses and other large vehicles to run on hydrogen and hydrogen mixes in the 1920's.
In 1975, Dr. Roger Billings put into service a hydrogen fueled ICE Winnebago 21-passenger bus which ran between the cities of Provo and Orem, Utah. This hydrogen bus had a Dodge engine and metal hydride tanks.
Of course hydrogen buses come in two varieties including ICE vehicles and fuel cell vehicles. Converting a transit bus with an internal combustion engine that was already running gasoline or diesel was far easier than developing a fuel cell.
Fuel cells for other applications such as tractor demonstrators and Apollo missions were developed beginning in the 1950's and 60's. But hydrogen fuel cells for buses are a more recent phenomenon.
For instance, the Chicago Transit Authority unveiled the first of their three hydrogen fuel cell buses in 1995. After this there have been many projects in the U. S. and Europe for rolling out prototype hydrogen fuel cell buses for pilot tests.
In Northern California in the U. S. in the Sacramento, Oakland, San Jose, San Francisco areas companies such as Sunline and AC Transit have rolled out a number of hydrogen fuel cell buses (most of them hybrids as well) and the latest of these versions is operating today.
In Europe and Australia, the Fuel Cell Bus Club was comprised of three different projects including CUTE, ECTOS and STEP. These projects make up the largest fuel cell bus fleet in the world.
Clean Urban Transport for Europe (CUTE) aimed at testing 27 Citaro hydrogen fuel cell buses in several cities in the European Union. Ecological City Transport System (ECTOS) was centered in Iceland and involved running hydrogen fuel cell buses around the city of Reykjavík, which also has the honor of unveiling the world's first hydrogen fueling station.
Sustainable Transport Energy for Perth (STEP) involved running three EcoBuses in Western Australia around the city of Perth. The buses went into operation in September 2004.
CUTE, ECTOS and STEP have now been rolled into one project called HyFLEET:CUTE which continues testing hydrogen fuel cell buses among many different cities, gathering and sharing data about fuel cells and hybrid systems.
In July 2006, Ford hydrogen shuttle buses went into production. Ford had intended to produce 20 H2 ICE shuttle buses, which held 12 passengers each. About 15 hydrogen shuttle buses were actually produced (some of the buyers backed out because of finances of lack of fueling stations) between 2006 and 2008, most of which are still in operation today and have logged around 350,000 miles.
Hydrogen fuel and buses are a natural fit. Since most city transit buses run the same routes, this means only a small number (as low as one) hydrogen fueling station is needed to supply the fuel. As the hydrogen fueling infrastructure continues to expand so will bus routes including those that travel to cities farther away and must refuel at a second station.
On this page of hydrogen bus pictures (PDF) there are several photos of both H2ICE and fuel cell buses over the years.viernes, 7 de enero de 2011
Fuel Cell Buses in US Transit Fleets
46490.pdf (application/pdf Objeto)
Lessons learned following almost four years of operation of the five Van Hool/UTC Power fuel cell buses at AC Transit, CTTRANSIT, and SunLine include:
• The demonstrations focused on proving that fuel cell transit buses can function in standard revenue transit service. The Van Hool/UTC Power fuel cell buses continue to be in standard revenue service since early 2006.
• The fuel cell power system manufacturer iterated its design, components, and implementation to explore reliability improvements, and is implementing these improvements in its new products.
• The energy storage and amount of on-board hydrogen fuel storage selected for these demonstrations were not optimal. Energy storage was problematic because implementation was not optimized with the hybrid propulsion system, and manufacturing quality control and shipping requirements were lacking. Also, the amount of hydrogen onboard was more than needed. The next-generation bus will use lithium ion batteries and carry less hydrogen onboard. These changes will reduce the weight of the bus by 6,000 lbs. The next-generation bus will be only 2,000 lbs heavier than a standard diesel bus.
• Demonstration participants expended great effort to educate the public about hydrogen and fuel cell propulsion in the locations where fuel cell transit buses were deployed. Two of the three locations surveyed their passengers to enhance public awareness of the buses and to obtain public impressions. Occasionally, the buses were provided to other locations for public events.
• Hydrogen fuel production and dispensing infrastructure has worked well for the three locations. However, scaling up for larger demonstrations and “greening” hydrogen production and delivery will require additional research and testing.
Progress and Needs
In the next few years, the United States will progress through stage-one introduction of fuel cell transit buses. Planned demonstrations will continue to address the following areas:
• Bus performance—The purpose of step-one demonstrations of fuel cell transit buses is to prove reliability and begin assessing fuel cell power systems and related components for durability. Hybrid/fuel cell systems must also be optimized for reliability and durability. Newer/next-generation fuel cell buses are optimizing on-board hydrogen storage and packaging. Step one is nearing completion in North America with larger orders of fuel cell buses for the ZEBA and BC Transit demonstrations.
• Fueling stations and hydrogen source—Providing wider and better fuel availability and optimizing fueling station sizes for multiple vehicles requires more hydrogen fueling stations. Scaling of hydrogen fueling stations will also be needed as larger fleets of fuel cell buses are demonstrated. In addition, it is important to prove that fuel can be clean and “green” at the same time for hydrogen produced and delivered at dispensing stations.
• Preparation for market introduction—Demonstration of larger numbers of hydrogen fuel cell transit buses requires market preparation, including assessing the availability of technologies and products; training fleet personnel and the public; developing codes and standards; and continuing data collection, analysis, and reporting.
• Cost reduction—Considering their current high capital cost, a priority regarding fuel cell transit buses is cost reduction. Cost reduction sufficient to make fuel cell buses competitive in the marketplace must be validated. However, purchase price has little relevance if the buses cannot meet performance standards. After fuel cell bus designs have proven performance and durability, the industry can investigate ways to reduce the cost of the buses and replacement components. As with all developmental technologies, larger-quantity orders can help manufacturers develop low-cost manufacturing techniques. The industry also needs to investigate ways to lower operational costs.
Lessons learned following almost four years of operation of the five Van Hool/UTC Power fuel cell buses at AC Transit, CTTRANSIT, and SunLine include:
• The demonstrations focused on proving that fuel cell transit buses can function in standard revenue transit service. The Van Hool/UTC Power fuel cell buses continue to be in standard revenue service since early 2006.
• The fuel cell power system manufacturer iterated its design, components, and implementation to explore reliability improvements, and is implementing these improvements in its new products.
• The energy storage and amount of on-board hydrogen fuel storage selected for these demonstrations were not optimal. Energy storage was problematic because implementation was not optimized with the hybrid propulsion system, and manufacturing quality control and shipping requirements were lacking. Also, the amount of hydrogen onboard was more than needed. The next-generation bus will use lithium ion batteries and carry less hydrogen onboard. These changes will reduce the weight of the bus by 6,000 lbs. The next-generation bus will be only 2,000 lbs heavier than a standard diesel bus.
• Demonstration participants expended great effort to educate the public about hydrogen and fuel cell propulsion in the locations where fuel cell transit buses were deployed. Two of the three locations surveyed their passengers to enhance public awareness of the buses and to obtain public impressions. Occasionally, the buses were provided to other locations for public events.
• Hydrogen fuel production and dispensing infrastructure has worked well for the three locations. However, scaling up for larger demonstrations and “greening” hydrogen production and delivery will require additional research and testing.
Progress and Needs
In the next few years, the United States will progress through stage-one introduction of fuel cell transit buses. Planned demonstrations will continue to address the following areas:
• Bus performance—The purpose of step-one demonstrations of fuel cell transit buses is to prove reliability and begin assessing fuel cell power systems and related components for durability. Hybrid/fuel cell systems must also be optimized for reliability and durability. Newer/next-generation fuel cell buses are optimizing on-board hydrogen storage and packaging. Step one is nearing completion in North America with larger orders of fuel cell buses for the ZEBA and BC Transit demonstrations.
• Fueling stations and hydrogen source—Providing wider and better fuel availability and optimizing fueling station sizes for multiple vehicles requires more hydrogen fueling stations. Scaling of hydrogen fueling stations will also be needed as larger fleets of fuel cell buses are demonstrated. In addition, it is important to prove that fuel can be clean and “green” at the same time for hydrogen produced and delivered at dispensing stations.
• Preparation for market introduction—Demonstration of larger numbers of hydrogen fuel cell transit buses requires market preparation, including assessing the availability of technologies and products; training fleet personnel and the public; developing codes and standards; and continuing data collection, analysis, and reporting.
• Cost reduction—Considering their current high capital cost, a priority regarding fuel cell transit buses is cost reduction. Cost reduction sufficient to make fuel cell buses competitive in the marketplace must be validated. However, purchase price has little relevance if the buses cannot meet performance standards. After fuel cell bus designs have proven performance and durability, the industry can investigate ways to reduce the cost of the buses and replacement components. As with all developmental technologies, larger-quantity orders can help manufacturers develop low-cost manufacturing techniques. The industry also needs to investigate ways to lower operational costs.
ISE Limited’s Fuel Cell Hybrid Drive System Provides Riders With Safe, Reliable, Zero-Emission Mass Transit at the 2010 Winter Games | FuelCellsWorks
martes, 4 de enero de 2011
battery-electric shuttle buses for China, India and US markets
Start-up AEV developing battery-electric shuttle buses for China, India and US markets
3 January 2011
| |
| Prototype of the AEV e-shuttle. Click to enlarge. |
Colorado-based American Electric Vehicles (AEV)—a company co-founded by Dr. Dan Rivers, who also co-founded Li-ion battery company Compact Power Inc. with LG Chem in 2000—is developing a 6.3m electric shuttle bus, with its primary markets intended to be China, India and the US.
The 18-passenger pilot eShuttle, which recently concluded efficiency testing in China, currently utilizes an 88.5 kWh lithium iron phosphate battery pack from its China-based partner NVT Battery and features a range of about 133 km (84 miles) without use of air conditioning and with a top speed of 80 km/h (50 mph) and consumption of 665 Wh/km.
| |
| AEV eShuttle powertrain block diagram. Click to enlarge. |
AEV is now making the detailed specification for the production shuttles, the first of which is scheduled to roll off the line on 30 June. The current eShuttle utilizes a first-generation motor and second-generation motor controller designed by AEV; the company is planning to switch to a second-generation motor later this year as it moves closer to delivery of production prototypes to customers. AEV also intends to move to a larger battery pack in the future.
The pack, Rivers notes, can be fairly easily slid out from the bus, and AEV will likely offer such a pack swap configuration as an option.
In an interview with GCC, Rivers noted that he and his experienced team have migrated from one area of the electric vehicle to another, starting out in the drive area with controllers, drivetrain and chargers, moving to the battery, and now ending up with the whole vehicle.
We looked at all the opportunities, and which part of the market is ready for EVs today. We zeroed in on electric shuttles for the fleet market for two main reasons. First, predictable routes. Second, lots of driving, intensive use. Predictability and intensity.
—Dan Rivers
In September 2010, AEV signed a manufacturing agreement with Bonluck Bus Manufacturing in China to assemble its vehicles for markets around the globe. In addition to manufacturing, the agreement also allows AEV to sell buses in China, India, and N. America.
Rivers said that the trends toward less expensive batteries and more expensive oil were combining to make an attractive value proposition. The startup looked to Hong Kong, China and India to see what those markets might need.
In India, we met with Delhi Metro Rail Corporation. They use small shuttles—a little smaller than 5.5m—to bring people into Delhi. On rail, the last mile transportation is to put people on shuttles and to move them around. A lot of these are professional people. The Government of India will do a matching grant with us on the shuttle.
—Dan Rivers
Rivers said that AEV’s goal for 2011 is to produce 50 shuttles, which will initially be targeted for southern China for testing and demonstration driving. However, Rivers notes, although the US is currently a secondary market, “We really want to be in the US. We think there is a great opportunity in the US.”
Partners. AEV is partnering with a company in China on the charger, and works with NVT Battery on the Li-ion pack. The motor is being developed with a US design company, and being produced by US-based Orchid International. AEV worked with Parker Hannifin on the instrument panel, which integrated two CANbus systems (the electrical drive system and “everything that is bus”—i.e., door opener, etc.). AEV is upgrading to include 3G cellular network connectivity in China.
Bonluck, AEV’s manufacturing partner, is a medium-sized bus company for China, Rivers said.
We found this medium-size company to have good technology, good quality. They were producing for export only. They are used to doing business overseas, and they had some interesting concepts, such as making a lightweight bus.
—Dan Rivers
AEV did work with LG Chem up to about 2008, Rivers said. However, he explained, LG has targeted the light electric vehicle and hybrid market, with its main production now being a cell that started its development with the Colorado team 10 years ago (and has now ended up in the Chevy Volt, among others).
Every cell is a compromise tailored for an application if you do it right. You want to make the pack as small as possible, but make it as powerful as possible. The [plug-in] hybrid pack design problem is about the hardest you can imagine—much more so than pure electric.
—Dan Rivers
Outlook. AEV intends to produce about 300 buses in 2012, Rivers said. Chris Groesbeck, AEV Global Director of Business Development (who was also with Rivers during CPI’s Colorado phase) noted that with respect to the US, “Our intention is not to become a bus company, our intention is to work with existing players here and fit into existing business models.”
Right now, AEV is looking at private fleets, and sees numbers there that will make it an attractive business.
With respect to the China market, Groesbeck notes that although there is a lot of competition there, AEV can leverage its technology advantage and partner with the right people and companies to get a piece of that market.
It is true that there is a lot of activity in China, but sometimes the reality is less than the hype. There are some 600 electric buses actually in operation today there, while annual sales of buses in China is about 200 to 300 thousand units. We are not latecomers.
—Dan Rivers
Comments
consultar fuentes RSS desde Excel
http://chandoo.org/wp/2008/07/30/rss-feeds-excel/
y por si desaparece del enlace:
RSS feeds are everywhere. So much that you cannot avoid them in your data processing, analytics or day to day spreadsheet needs.
y por si desaparece del enlace:
RSS feeds are everywhere. So much that you cannot avoid them in your data processing, analytics or day to day spreadsheet needs.
If you can get the RSS feeds to excel sheet you can do pretty interesting things with it, like:
- Prepare a sheet to watch deals on Amazon, Craigslist, Deals2buy and other favorite sites
- Watch news, alerts on your company / brand / blog using technorati, google news etc.
- So much more, just use your imagination
Of course, Excel 2003 (and above) has XML import option using which you can get any XML files (and thus RSS files too) and show them in spreadsheet. But the problem is, the layout is messy, and too confusing. So here is a simpler way to read RSS/ATOM/XML feeds from excel sheets.
For this example, let us build an excel sheet that will fetch Amazon Gold box Today’s deals RSS feed show all deal titles and product URLs.
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First Create a new Google Docs – Spreadsheet
We will use a round about way to get RSS feed to our excel sheet. Create a new google docs – spreadsheet. We will now use google’s importfeed() external data function. This function fetches external feed data and loads it in to the spreadsheet. We will write this function in 2 columns, one for the feed title telling us what the goldbox deal is about and another with the product’s URL.
The syntax will look like:
=ImportFeed("http://rssfeeds.s3.amazonaws.com/goldbox", "items title",true,20)for deal title and=ImportFeed("http://rssfeeds.s3.amazonaws.com/goldbox", "items url",true,20)for the URL.When done, the sheet should display gold box deals like below:
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Now share the google doc as text file to access from excel sheet
Once the feed is fetched to the google doc, we will share this sheet as a txt file so that we can read the gold box deals from excel. You can share the google doc by clicking “Publish” option available to the right.
We will select the “more publishing options” to share this sheet as a txt file. Click here to see a sample shared txt file containing latest 20 gold box deals.
Make sure you have clicked on the “Automatically republish this document when changes are made” option.
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Finally read the text file from excel using web queries
In the excel sheet we will create a new web query to connect to our shared text file using menu > data > import external data > new web query as shown below:
We will mention the URL of the shared google doc in the web query dialog and select everything. See below:
That is all, we have now fed our excel sheet with tasty gold box deals. When you need new deals just “refresh data”
download the excel sheet with rss feeds to spreadsheet example and play around
Do you like this? Tell me what would you do if you get RSS feeds to excel sheets?
domingo, 2 de enero de 2011
consulta de datos externos
Esta nueva función permite obtener información de tipos de archivo como .xml, .html, .csv o .tsv, así como de feeds RSS y Atom que podrías leer hoy en Google Reader.
Recuerda que: Estas funciones sólo pueden leer archivos públicos disponibles. Si un archivo está protegido por un cortafuegos, o si se debe iniciar sesión para verlo, no podremos extraer contenido de él. Sólo podrás hacer referencia a datos de otras hojas de cálculo cuando éstas se publiquen.
Además, el límite de funciones por cada hoja de cálculo es de 50.
Funciones:
=importXML("URL";"consulta")
- URL: la URL del archivo XML o HTML.
- consulta: la consulta XPath que se va a aplicar en los datos proporcionados en la URL. Por ejemplo, "//a/@href" devuelve una lista con los atributos href de todas las etiquetas del documento (es decir, todas las URL con las que está enlazado el documento). Para obtener más información sobre XPath, consulta http://www.w3schools.com/xpath/
- Ejemplo: =importXml("www.google.com"; "//a/@href"). Esto devuelve todos los atributos href (las URL enlazadas) de todas las etiquetas de la página principal de www.google.com.
=importData("URL")
- URL: la URL del archivo CSV o TSV. Esta acción importa un archivo separado por comas o tabuladores.
=ImportHtml(URL; "lista" | "tabla"; índice). Importa los datos de una lista o tabla específica de una página HTML. Los argumentos de la función son los siguientes:
- URL: la URL de la página HTML
- "lista" o "tabla" para indicar el tipo de estructura que se extraerá de la página web. Si es "lista", la función buscará el contenido de las etiquetas
- ,
- índice: el índice basado en 1 de la tabla o de la lista de la página web de origen. Los índices se mantienen por separado, por lo que podría haber una lista #1 y una tabla #1.
- Ejemplo: =ImportHtml("http://en.wikipedia.org/wiki/Demographics_of_India"; "tabla";4). Esta función devuelve información demográfica sobre la población de India.
- URL: la URL del feed RSS o ATOM.
- feedQuery/itemQuery: una de las siguientes cadenas de consulta: "feed", "título de feed", "autor de feed", "descripción de feed", "URL de feed", "elementos", "autor de elementos", "título de elementos", "resumen de elementos", "URL de elementos" o "elementos creados". Las consultas de feed devuelven propiedades del feed de modo general: el título del feed, autor del feed, etc. Nota: para obtener los datos del feed, debes introducir una solicitud "elementos".
- La consulta "feed" devuelve la información del feed en una sola fila.
- La consulta "feed
" devuelve la información solicitada del feed en una sola celda. - La consulta "elementos" devuelve una tabla completa con la información de todos los elementos del feed.
- La consulta "elementos
" devuelve la información solicitada de cada elemento en una sola columna. - Si una consulta determinada empieza por "feed", el parámetro "numItems" no es necesario y se sustituye por los parámetros de encabezado opcionales.
- Si una consulta determinada empieza por "items", el parámetro "numItems" debe aparecer como tercer parámetro, y los encabezados en cuarto lugar.
- encabezados: "true" para los encabezados de columna. Esta acción añadirá una fila más a la parte superior y etiquetará las columnas del resultado.
- Ejemplo: =ImportFeed("http://news.google.com/?output=atom")
- o
- ; si es "tabla", el de las etiquetas
.
=ImportFeed(URL; [feedQuery | itemQuery]; [headers]; [numItems]). Esta función importa un feed RSS o ATOM, al igual que se puede hacer en Google Reader. Los argumentos de la función son los siguientes:
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This is a good looking bus. I favor more smaller buses that would run more often in the U.S. Cities could run more buses with a greater percentage of rider capacity and no one would have to wait long for a ride.
Posted by: SJC | January 03, 2011 at 11:34 AM
The trouble with more smaller buses is unionized drivers high salaries and fringe benefits (over $80 per hour effectively worked in many countries). Many geographically large cites have taken an opposite direct with 100+ passenger articulated buses to reduce drivers cost. Smaller e-buses would make sense in China, India, Brazil, and similar countries with large population and lower drivers salary, but not is USA, Europe, Australia, Canada etc where drivers salaries are very high.
Small electric buses could make sense if passengers take turn driving it or part time student or with unemployed part time drivers at $10/hour.
The opposite would be driver less buses on rails.
Posted by: HarveyD | January 03, 2011 at 11:56 AM
And lets go manufacture them in China. Yet another company trying to help China's poor economy because we have so many extra jobs here??? LOL
Posted by: DaveD | January 03, 2011 at 12:15 PM
@HarveyD:
Can you provide some reference to support your assertions about high driver salaries? At:
http://www.careerbliss.com/salary/bus-driver-at-ac-transit-salaries-342953/
...I find AC Transit bus drivers average something like $61K/year which works out to less than $30/hour. This is in the high cost San Francisco Bay Area. Benefits may add another $10 to $15 to that, but it is far less than the $80 you are quoting.
Posted by: Nick Lyons | January 03, 2011 at 12:54 PM
...in addition, I would bet the shuttle bus drivers who get me from the Oakland airport to the car rental place are making far less than the AC Transit guys.
Posted by: Nick Lyons | January 03, 2011 at 12:56 PM
Bus drivers are not overpaid. The problem is the cost of healthcare.
More people would be inclined to take the bus if it were quieter, as these should be.
Posted by: danm | January 03, 2011 at 01:50 PM
I agree bus drivers are not overpaid. The issue, though is the cost for drivers. If, with benefits, it is $50 per hour, that is 50 passengers you need every hour, including non-rush hours, at $1 each just for the driver. So, at what point does it cost too much to look valuable to the passenger -- particularly when they only see their gas bill once a month on the credit card.
If people had to pay cash every day for the gas they use, the depreciation and insurance on their car, and parking, they might be able to compare costs.
Oh yes, and that still does not address that question of frequency. If we could automate the buses and do away with the drivers, then smaller, more frequent buses would make sense in the community.
Posted by: JMartin | January 03, 2011 at 03:39 PM
2010 Toyota Corolla
Base 4-Spd AT
MSRP $16,250
Total Cost to Own
$34,515
5 YEAR AVERAGE FOR CALIFORNIA
http://autos.yahoo.com/2010_toyota_corolla_base_4_spd_at/
All this information is available, most people just choose to ignore it. It is easier just to assume that most people buy and drive cars, so why not them?
Posted by: SJC | January 03, 2011 at 04:02 PM
NL: In our city, bus drivers have a basic $69K pay. Since there are no broken shifts, the majority only work 4 hours/day during peak hours and get paid for 8 hours. Many will work two 4-hour peak periods and get paid for a two 8-hour shift. The first shift gets them 8 hours pay while the other gets 8x2=16 hours. So for driving two 4-hour periods, in the same day, they get paid for 24 hours. The average driver with 6+ years experience get $76k + another $30K++ for so-called overtime = $110K + xx$K in fringe benefits. The latest evaluation is a minimum of $80/hour for every hour scheduled to work. However, they get well over $120 for every hour really worked. Senior drivers get even more.
At $2.25 per passenger, they collect barely enough to pay the drivers. All other expenses are deficits paid with various taxes. The real total cost per ride is over $4. With smaller buses, that could go as high as $7 to $8 per ride unless you find a way to do away with drivers. People with e-cars will probably go to work down town at lower cost than those larges buses. Subways and suburban e-trains are very different. One driver can move 900 people at much higher speed using clean electricity. That should be the way to go.
Beijing has constructed 3 more subways line (136+ km) in the last 4 years. The current 440 km will be doubled in the next 10 to 15 years. That is the best solution for all large cities.
Smaller buses may be ok as shuttle buses on special steady load routes with lower paid drivers.
Posted by: HarveyD | January 03, 2011 at 04:37 PM
@HarveyD:
What city do you live in? I'm actually quite a good driver...
Posted by: Nick Lyons | January 03, 2011 at 08:53 PM
@Nick
...I find AC Transit bus drivers average something like $61K/year which works out to less than $30/hour. This is in the high cost San Francisco Bay Area. Benefits may add another $10 to $15 to that, but it is far less than the $80 you are quoting.
When I first read this I realized you were basing your numbers on an equivalent to a 9-to-5/50weeks a year job. That's just not how it is, as Harvey explains later.
Posted by: ai_vin | January 03, 2011 at 09:37 PM
We had such a small bus system here for a bit but ya the cost went freaky and to be blunt the people serviced .. well we didnt give a crap about them anyway.. not enough to pay that fricken much.
Posted by: wintermane2000 | January 03, 2011 at 09:58 PM
The idea of a 6am 8pm shifts, "peaking" diver without an automatic transmission is definitely a frightening thought.
While the drivers of our youth were not dressed or spoken as elouquently as the passengers, in the modern city, traffic pace, allowed lane width and the pressures of life generally makes this idea a truly large commitment.
I think that perceiving the driver as stressed and over pressured is the worst advertisment to passengers.
specialist occupation.?
Posted by: Arnold | January 03, 2011 at 10:17 PM