Google Chrome is a web browser developed by Google that uses the WebKit layout engine and application framework. It was first released as a beta version for Microsoft Windows on 2 September 2008, and the public stable release was on 11 December 2008. The name is derived from the graphical user interface frame, or "chrome", of web browsers. As of December 2009[update], Chrome was the third most widely used browser, with 4.63% of worldwide usage share of web browsers.
In September 2008, Google released the entire source code of Chrome, including its V8 JavaScript engine, as an open source project entitled Chromium. This move enabled third-party developers to study the underlying source code and help port the browser to Mac OS X and Linux. A Google spokesperson also expressed hope that other browsers would adopt V8 to help web applications. The Google-authored portion of Chromium is released under the permissive BSD license, which allows portions to be incorporated into both open source and proprietary software programs. Other portions of the source code are subject to a variety of open-source licenses. Chromium implements the same feature set as Chrome, but without Google branding and automatic updates, and it has a slightly different logo.
History:
Announcement
The release announcement was originally scheduled for 3 September 2008, and a comic by Scott McCloud was to be sent to journalists and bloggers explaining the features of and motivations for the new browser. Copies intended for Europe were shipped early and German blogger Philipp Lenssen of Google Blogoscoped made a scanned copy of the 38-page comic available on his website after receiving it on 1 September 2008. Google subsequently made the comic available on Google Books and mentioned it on their official blog along with an explanation for the early release.
Public release
The browser was first publicly released for Microsoft Windows (XP and later only) on 2 September 2008 in 43 languages, officially a beta version. Chrome quickly gained about 1% market share despite Mac OS X and Linux versions still being under development. After the initial surge, usage share dropped until it hit a low of 0.69% in October 2008. It then started rising again until by December 2008, Chrome again passed the 1% threshold.
In late 2008, a message saying that a "test shell" is available to build on Linux was placed in the Chromium project's developer wiki. Some tried this shell, which apparently lacked many features, but appeared to function quite well in rendering web sites (including JavaScript). In early January 2009, CNET reported that Google planned to release versions for Mac OS X and Linux in the first half of the year. By March 2009, it was possible to build a pre-alpha version of the Chromium browser, which looked similar to the Windows release, but was still very far from complete.
The first official Chrome Mac OS X and Linux developer previews were announced on 4 June 2009 with a blog post saying they were missing many features and were intended for early feedback rather than general use. On 9 October 2009, Google CEO Eric Schmidt stated that Chrome for Mac would be released "in a couple of months." On 30 November 2009, it was reported that the Mac OS X beta would be available by the end of 2009, lacking such features as App Mode, a bookmark manager, 64-bit support, Bookmark Sync, and extensions.
Official betas for Mac OS X and Linux were released on 8 December 2009.
Development
Chrome was assembled from 25 different code libraries from Google and third parties such as Netscape. The JavaScript virtual machine was considered a sufficiently important project to be split off (as was Adobe/Mozilla's Tamarin) and handled by a separate team in Denmark coordinated by Lars Bak at Aarhus. According to Google, existing implementations were designed "for small programs, where the performance and interactivity of the system weren't that important," but web applications such as Gmail "are using the web browser to the fullest when it comes to DOM manipulations and Javascript", and therefore would significantly benefit from a JavaScript engine that could work faster.
Chrome uses the WebKit rendering engine to display web pages, on advice from the Android team. Like most browsers, Chrome was extensively tested internally before release with unit testing, "automated user interface testing of scripted user actions" and fuzz testing, as well as WebKit's layout tests (99% of which Chrome is claimed to have passed). New browser builds are automatically tested against tens of thousands of commonly accessed websites inside of the Google index within 20–30 minutes.
Chrome includes Gears, which adds features for web developers typically relating to the building of web applications (including offline support).
The first release of Google Chrome passed the Acid1 and Acid2 tests, but not Acid3. On Acid3 it scored 79 out of the 100 subtests, higher than contemporary versions of Internet Explorer 7 (14/100), Firefox 3 (71/100), and Safari 3 (75/100); but lower than Opera 9 (83/100). When compared with contemporary development builds of Firefox, Internet Explorer, Opera, and Safari, Chrome scored lower than Firefox 3.1 Beta 1 (85/100), Opera (100/100), and Safari 4 (100/100); but still higher than Internet Explorer (21/100). However, version 2.0 of Google Chrome passed all 100 subtests (but still failed the link test).[citation needed] The current stable version (3.0) scores 100/100 but shows a 'X' in the upper right corner because downloadable fonts are disabled until security concerns surrounding them can be resolved. Development builds of Google Chrome starting with version 4.0.249.4 and higher pass all aspects of the Acid 3 test, including the link test and downloadable fonts.
On 7 July 2009, Google announced plans for a Google Chrome OS based on the Chrome browser and Linux.
Google released Chrome 2.0 on 21 May 2009, citing increased speed and stability. New features included form autofill, an improved New Tab Page, and full screen mode.
search
Custom Search
mardi 2 mars 2010
Google Maps
Google Maps (for a time named Google Local) is a basic web mapping service application and technology provided by Google, free (for non-commercial use), that powers many map-based services, including the Google Maps website, Google Ride Finder, Google Transit, and maps embedded on third-party websites via the Google Maps API. It offers street maps, a route planner for traveling by foot, car, or public transport and an urban business locator for numerous countries around the world. According to one of its creators (Lars Rasmussen), Google Maps is "a way of organizing the world's information geographically".
Google Maps uses the Mercator projection, so it cannot show areas around the poles. A related product is Google Earth, a stand-alone program for Microsoft Windows, Mac OS X, Linux, SymbianOS, and iPhone OS which offers more globe-viewing features, including showing polar areas.
Satellite view:
Google Maps provides high-resolution satellite images for most urban areas in the United States (including Hawaii, Alaska, Puerto Rico, and the U.S. Virgin Islands), Canada, and the United Kingdom, as well as parts of Australia and many other countries. The high-resolution imagery has been used by Google Maps to cover all of Egypt's Nile Valley, Sahara desert and Sinai. Google Maps also covers many cities in the English speaking areas. However, Google Maps is not solely an English maps service, since its service is intended to cover the world. The highest-resolution images are in some Japanese cities, such as Tokyo.
Various governments have complained about the potential for terrorists to use the satellite images in planning attacks. Google has blurred some areas for security (mostly in the United States), including the U.S. Naval Observatory area (where the official residence of the Vice President is located), and previously[citation needed] the United States Capitol and the White House (which formerly featured this erased housetop). Other well-known government installations, including Area 51 in the Nevada desert, are visible. Not all areas on satellite images are covered in the same resolution; less populated areas usually get less detail. Some areas may be obscured by patches of clouds.
With the introduction of an easily pannable and searchable mapping and satellite imagery tool, Google's mapping engine prompted a surge of interest in satellite imagery. Sites were established which feature satellite images of interesting natural and man-made landmarks, including such novelties as "large type" writing visible in the imagery, as well as famous stadia and unique geological formations. As of November 2008[update], the U.S. National Weather Service also now uses Google Maps within its local weather forecasts, showing the 5 x 5 km "point forecast" squares used in forecast models. Although Google uses the word satellite, most of the high-resolution imagery is aerial photography taken from airplanes rather than from satellites.
Google Maps uses the Mercator projection, so it cannot show areas around the poles. A related product is Google Earth, a stand-alone program for Microsoft Windows, Mac OS X, Linux, SymbianOS, and iPhone OS which offers more globe-viewing features, including showing polar areas.
Satellite view:
Google Maps provides high-resolution satellite images for most urban areas in the United States (including Hawaii, Alaska, Puerto Rico, and the U.S. Virgin Islands), Canada, and the United Kingdom, as well as parts of Australia and many other countries. The high-resolution imagery has been used by Google Maps to cover all of Egypt's Nile Valley, Sahara desert and Sinai. Google Maps also covers many cities in the English speaking areas. However, Google Maps is not solely an English maps service, since its service is intended to cover the world. The highest-resolution images are in some Japanese cities, such as Tokyo.
Various governments have complained about the potential for terrorists to use the satellite images in planning attacks. Google has blurred some areas for security (mostly in the United States), including the U.S. Naval Observatory area (where the official residence of the Vice President is located), and previously[citation needed] the United States Capitol and the White House (which formerly featured this erased housetop). Other well-known government installations, including Area 51 in the Nevada desert, are visible. Not all areas on satellite images are covered in the same resolution; less populated areas usually get less detail. Some areas may be obscured by patches of clouds.
With the introduction of an easily pannable and searchable mapping and satellite imagery tool, Google's mapping engine prompted a surge of interest in satellite imagery. Sites were established which feature satellite images of interesting natural and man-made landmarks, including such novelties as "large type" writing visible in the imagery, as well as famous stadia and unique geological formations. As of November 2008[update], the U.S. National Weather Service also now uses Google Maps within its local weather forecasts, showing the 5 x 5 km "point forecast" squares used in forecast models. Although Google uses the word satellite, most of the high-resolution imagery is aerial photography taken from airplanes rather than from satellites.
Google Maps
Google Maps (for a time named Google Local) is a basic web mapping service application and technology provided by Google, free (for non-commercial use), that powers many map-based services, including the Google Maps website, Google Ride Finder, Google Transit, and maps embedded on third-party websites via the Google Maps API. It offers street maps, a route planner for traveling by foot, car, or public transport and an urban business locator for numerous countries around the world. According to one of its creators (Lars Rasmussen), Google Maps is "a way of organizing the world's information geographically".
Google Maps uses the Mercator projection, so it cannot show areas around the poles. A related product is Google Earth, a stand-alone program for Microsoft Windows, Mac OS X, Linux, SymbianOS, and iPhone OS which offers more globe-viewing features, including showing polar areas.
Satellite view:
Google Maps provides high-resolution satellite images for most urban areas in the United States (including Hawaii, Alaska, Puerto Rico, and the U.S. Virgin Islands), Canada, and the United Kingdom, as well as parts of Australia and many other countries. The high-resolution imagery has been used by Google Maps to cover all of Egypt's Nile Valley, Sahara desert and Sinai. Google Maps also covers many cities in the English speaking areas. However, Google Maps is not solely an English maps service, since its service is intended to cover the world. The highest-resolution images are in some Japanese cities, such as Tokyo.
Various governments have complained about the potential for terrorists to use the satellite images in planning attacks. Google has blurred some areas for security (mostly in the United States), including the U.S. Naval Observatory area (where the official residence of the Vice President is located), and previously[citation needed] the United States Capitol and the White House (which formerly featured this erased housetop). Other well-known government installations, including Area 51 in the Nevada desert, are visible. Not all areas on satellite images are covered in the same resolution; less populated areas usually get less detail. Some areas may be obscured by patches of clouds.
With the introduction of an easily pannable and searchable mapping and satellite imagery tool, Google's mapping engine prompted a surge of interest in satellite imagery. Sites were established which feature satellite images of interesting natural and man-made landmarks, including such novelties as "large type" writing visible in the imagery, as well as famous stadia and unique geological formations. As of November 2008[update], the U.S. National Weather Service also now uses Google Maps within its local weather forecasts, showing the 5 x 5 km "point forecast" squares used in forecast models. Although Google uses the word satellite, most of the high-resolution imagery is aerial photography taken from airplanes rather than from satellites.
Google Maps uses the Mercator projection, so it cannot show areas around the poles. A related product is Google Earth, a stand-alone program for Microsoft Windows, Mac OS X, Linux, SymbianOS, and iPhone OS which offers more globe-viewing features, including showing polar areas.
Satellite view:
Google Maps provides high-resolution satellite images for most urban areas in the United States (including Hawaii, Alaska, Puerto Rico, and the U.S. Virgin Islands), Canada, and the United Kingdom, as well as parts of Australia and many other countries. The high-resolution imagery has been used by Google Maps to cover all of Egypt's Nile Valley, Sahara desert and Sinai. Google Maps also covers many cities in the English speaking areas. However, Google Maps is not solely an English maps service, since its service is intended to cover the world. The highest-resolution images are in some Japanese cities, such as Tokyo.
Various governments have complained about the potential for terrorists to use the satellite images in planning attacks. Google has blurred some areas for security (mostly in the United States), including the U.S. Naval Observatory area (where the official residence of the Vice President is located), and previously[citation needed] the United States Capitol and the White House (which formerly featured this erased housetop). Other well-known government installations, including Area 51 in the Nevada desert, are visible. Not all areas on satellite images are covered in the same resolution; less populated areas usually get less detail. Some areas may be obscured by patches of clouds.
With the introduction of an easily pannable and searchable mapping and satellite imagery tool, Google's mapping engine prompted a surge of interest in satellite imagery. Sites were established which feature satellite images of interesting natural and man-made landmarks, including such novelties as "large type" writing visible in the imagery, as well as famous stadia and unique geological formations. As of November 2008[update], the U.S. National Weather Service also now uses Google Maps within its local weather forecasts, showing the 5 x 5 km "point forecast" squares used in forecast models. Although Google uses the word satellite, most of the high-resolution imagery is aerial photography taken from airplanes rather than from satellites.
Google Earth
Google Earth is a virtual globe, map and geographic information program that was originally called EarthViewer 3D, and was created by Keyhole, Inc, a company acquired by Google in 2004. It maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and GIS 3D globe. It is available under three different licenses: Google Earth, a free version with limited functionality; Google Earth Plus (discontinued), which included additional features; and Google Earth Pro ($400 per year), which is intended for commercial use.
The product, re-released as Google Earth in 2005, is currently available for use on personal computers running Windows 2000 and above, Mac OS X 10.3.9 and above, Linux Kernel: 2.4 or later (released on June 12, 2006), and FreeBSD. Google Earth is also available as a browser plugin which was released on May 28, 2008. It was also made available on the iPhone OS on October 27, 2008, as a free download from the App Store. In addition to releasing an updated Keyhole based client, Google also added the imagery from the Earth database to their web based mapping software. The release of Google Earth in June 2005 to the public caused a more than tenfold increase in media coverage on virtual globes between 2005 and 2006, driving public interest in geospatial technologies and applications.
Overview:
Google Earth displays satellite images of varying resolution of the Earth's surface, allowing users to see things like cities and houses looking perpendicularly down or at an oblique angle, with perspective (see also bird's eye view). The degree of resolution available is based somewhat on the points of interest and popularity, but most land (except for some islands) is covered in at least 15 meters of resolution. Melbourne, Victoria, Australia; Las Vegas, Nevada; and Cambridge, Cambridgeshire include examples of the highest resolution, at 15 cm (6 inches). Google Earth allows users to search for addresses for some countries, enter coordinates, or simply use the mouse to browse to a location.
For large parts of the surface of the Earth only 2D images are available, from almost vertical photography. Viewing this from an oblique angle, there is perspective in the sense that objects which are horizontally far away are seen smaller, but of course it is like viewing a large photograph, not quite like a 3D view.
For other parts of the surface of the Earth 3D images of terrain and buildings are available. Google Earth uses digital elevation model (DEM) data collected by NASA's Shuttle Radar Topography Mission (SRTM). This means one can view the Grand Canyon or Mount Everest in three dimensions, instead of 2D like other areas. Since November 2006, the 3D views of many mountains, including Mount Everest, have been improved by the use of supplementary DEM data to fill the gaps in SRTM coverage.
Many people use the applications to add their own data, making them available through various sources, such as the Bulletin Board Systems (BBS) or blogs mentioned in the link section below. Google Earth is able to show all kinds of images overlaid on the surface of the earth and is also a Web Map Service client. Google Earth supports managing three-dimensional Geospatial data through Keyhole Markup Language (KML).
Google Earth has the capability to show a 3D buildings and structures (such as bridges), which consist of users' submissions using SketchUp, a 3D modeling program. In prior versions of Google Earth (before Version 4), 3D buildings were limited to a few cities, and had poorer rendering with no textures. Many buildings and structures from around the world now have detailed 3D structures; including (but not limited to) those in the United States, Canada, Ireland, India, Japan, United Kingdom ,Germany, Pakistan and the cities, Amsterdam and Alexandria. In August 2007, Hamburg became the first city entirely shown in 3D, including textures such as façades. The Irish town of Westport was added to Google Earth in 3D on January 16, 2008. The 'Westport3D' model was created by 3D imaging firm AM3TD using long-distance laser scanning technology and digital photography and is the first such model of an Irish town to be created. As it was developed initially to aid Local Government in carrying out their town planning functions it includes the highest resolution photo-realistic textures to be found anywhere in Google Earth. Three-dimensional renderings are available for certain buildings and structures around the world via Google's 3D Warehouse and other websites.
Recently, Google added a feature that allows users to monitor traffic speeds at loops located every 200 yards in real-time. In version 4.3 released on April 15, 2008, Google Street View was fully integrated into the program allowing the program to provide an on the street level view in many locations.
On January 17, 2009, the entirety of Google Earth's ocean floor imagery was updated to new images by SIO, NOAA, US Navy, NGA, and GEBCO. The new images have caused smaller islands, such as some atolls in the Maldives, to be rendered invisible despite their shores being completely outlined. On October 21, 2009, whole Poland territory imagery was updated (many places were impossible to overview, in low resolution, now they're updated), and - in places - downgraded (in very good resolution, now with medium).
The product, re-released as Google Earth in 2005, is currently available for use on personal computers running Windows 2000 and above, Mac OS X 10.3.9 and above, Linux Kernel: 2.4 or later (released on June 12, 2006), and FreeBSD. Google Earth is also available as a browser plugin which was released on May 28, 2008. It was also made available on the iPhone OS on October 27, 2008, as a free download from the App Store. In addition to releasing an updated Keyhole based client, Google also added the imagery from the Earth database to their web based mapping software. The release of Google Earth in June 2005 to the public caused a more than tenfold increase in media coverage on virtual globes between 2005 and 2006, driving public interest in geospatial technologies and applications.
Overview:
Google Earth displays satellite images of varying resolution of the Earth's surface, allowing users to see things like cities and houses looking perpendicularly down or at an oblique angle, with perspective (see also bird's eye view). The degree of resolution available is based somewhat on the points of interest and popularity, but most land (except for some islands) is covered in at least 15 meters of resolution. Melbourne, Victoria, Australia; Las Vegas, Nevada; and Cambridge, Cambridgeshire include examples of the highest resolution, at 15 cm (6 inches). Google Earth allows users to search for addresses for some countries, enter coordinates, or simply use the mouse to browse to a location.
For large parts of the surface of the Earth only 2D images are available, from almost vertical photography. Viewing this from an oblique angle, there is perspective in the sense that objects which are horizontally far away are seen smaller, but of course it is like viewing a large photograph, not quite like a 3D view.
For other parts of the surface of the Earth 3D images of terrain and buildings are available. Google Earth uses digital elevation model (DEM) data collected by NASA's Shuttle Radar Topography Mission (SRTM). This means one can view the Grand Canyon or Mount Everest in three dimensions, instead of 2D like other areas. Since November 2006, the 3D views of many mountains, including Mount Everest, have been improved by the use of supplementary DEM data to fill the gaps in SRTM coverage.
Many people use the applications to add their own data, making them available through various sources, such as the Bulletin Board Systems (BBS) or blogs mentioned in the link section below. Google Earth is able to show all kinds of images overlaid on the surface of the earth and is also a Web Map Service client. Google Earth supports managing three-dimensional Geospatial data through Keyhole Markup Language (KML).
Google Earth has the capability to show a 3D buildings and structures (such as bridges), which consist of users' submissions using SketchUp, a 3D modeling program. In prior versions of Google Earth (before Version 4), 3D buildings were limited to a few cities, and had poorer rendering with no textures. Many buildings and structures from around the world now have detailed 3D structures; including (but not limited to) those in the United States, Canada, Ireland, India, Japan, United Kingdom ,Germany, Pakistan and the cities, Amsterdam and Alexandria. In August 2007, Hamburg became the first city entirely shown in 3D, including textures such as façades. The Irish town of Westport was added to Google Earth in 3D on January 16, 2008. The 'Westport3D' model was created by 3D imaging firm AM3TD using long-distance laser scanning technology and digital photography and is the first such model of an Irish town to be created. As it was developed initially to aid Local Government in carrying out their town planning functions it includes the highest resolution photo-realistic textures to be found anywhere in Google Earth. Three-dimensional renderings are available for certain buildings and structures around the world via Google's 3D Warehouse and other websites.
Recently, Google added a feature that allows users to monitor traffic speeds at loops located every 200 yards in real-time. In version 4.3 released on April 15, 2008, Google Street View was fully integrated into the program allowing the program to provide an on the street level view in many locations.
On January 17, 2009, the entirety of Google Earth's ocean floor imagery was updated to new images by SIO, NOAA, US Navy, NGA, and GEBCO. The new images have caused smaller islands, such as some atolls in the Maldives, to be rendered invisible despite their shores being completely outlined. On October 21, 2009, whole Poland territory imagery was updated (many places were impossible to overview, in low resolution, now they're updated), and - in places - downgraded (in very good resolution, now with medium).
Google Scholar
Google Scholar is a freely-accessible Web search engine that indexes the full text of scholarly literature across an array of publishing formats and disciplines. Released in beta in November 2004, the Google Scholar index includes most peer-reviewed online journals of Europe and America's largest scholarly publishers. It is similar in function to the freely-available Scirus from Elsevier, CiteSeerX, and getCITED. It is also similar to the subscription-based tools, Elsevier's Scopus and Thomson ISI's Web of Science. Its advertising slogan — "Stand on the shoulders of giants" — is a nod to the scholars who have contributed to their fields over the centuries, providing the foundation for new intellectual achievements.
Features and specifications:
Google Scholar allows users to search for digital or physical copies of articles, whether online or in libraries. Google Scholar is relatively quick and easy to use. “Scholarly” searches will appear using the references from “’full-text journal articles, technical reports, preprints, theses, books, and other documents, including selected Web pages that are deemed to be “scholarly. Because most of Google Scholar's search results link directly to commercial journal articles, a majority of the time users will only be able to access a brief summary of the articles topics, and small amounts of important information regarding the article, and possibly will have to pay a fee to access the entire article. Google Scholar is as easy to use as the normal Google web search can be, especially with the helpfulness of the "advanced search" option, which can automatically narrow search results to a specific journal or article. The most relevant results for the searched keywords will be listed first, in order of the authors ranking, the amount of references that are linked to it and their relevance to other scholarly literature, and the ranking of the publication that the journal appears in.
Using its "group of" feature, it shows the available links to journal articles. In the 2005 version, this feature provided a link to both subscription-access versions of an article and to free full-text versions of articles; for most of 2006, it provided links to only the publishers' versions. Since December 2006, it has provided links to both published versions and major open access repositories, but still does not cover those posted on individual faculty web pages; access to such self-archived non-subscription versions is now provided by a link to Google, where one can find such open access articles.
Through its "cited by" feature, Google Scholar provides access to abstracts of articles that have cited the article being viewed. It is this feature in particular that provides the citation indexing previously only found in Scopus and Web of Knowledge. Through its "Related articles" feature, Google Scholar presents a list of closely related articles, ranked primarily by how similar these articles are to the original result, but also taking into account the relevance of each paper.
Criticism:
Some searchers consider Google Scholar of comparable quality and utility to commercial databases, even though its user-interface (UI) is still in beta. The reviews recognize that its "cited by" feature in particular poses serious competition to Scopus and ISI Web of Knowledge, although it generally returns fewer results than subscription services.
A significant problem with Google Scholar is the secrecy about its coverage. Some publishers do not allow it to crawl their journals. Elsevier journals were not included before mid-2007, when Elsevier began to make most of its ScienceDirect content available to Google Scholar and Google's web search. As of February 2008 the absentees still included the most recent years of the American Chemical Society journals. Google Scholar does not publish a list of scientific journals crawled, and the frequency of its updates is unknown. It is therefore impossible to know how current or exhaustive searches are in Google Scholar. Nonetheless, it allows easy access to published articles without the difficulties encountered in some of the most expensive commercial databases.Google Scholar has problems identifying publications on the arXiv preprint server correctly. Interpunctuation characters in titles produce wrong search results, and authors are assigned to wrong papers, which leads to erroneous additional search results. Some search results are even given without any comprehensible reason. Google Scholar was not developed to aid someone who is seeking out intense medical clinical questions, but was developed to share the basics of what the importance of the topic is.
Features and specifications:
Google Scholar allows users to search for digital or physical copies of articles, whether online or in libraries. Google Scholar is relatively quick and easy to use. “Scholarly” searches will appear using the references from “’full-text journal articles, technical reports, preprints, theses, books, and other documents, including selected Web pages that are deemed to be “scholarly. Because most of Google Scholar's search results link directly to commercial journal articles, a majority of the time users will only be able to access a brief summary of the articles topics, and small amounts of important information regarding the article, and possibly will have to pay a fee to access the entire article. Google Scholar is as easy to use as the normal Google web search can be, especially with the helpfulness of the "advanced search" option, which can automatically narrow search results to a specific journal or article. The most relevant results for the searched keywords will be listed first, in order of the authors ranking, the amount of references that are linked to it and their relevance to other scholarly literature, and the ranking of the publication that the journal appears in.
Using its "group of" feature, it shows the available links to journal articles. In the 2005 version, this feature provided a link to both subscription-access versions of an article and to free full-text versions of articles; for most of 2006, it provided links to only the publishers' versions. Since December 2006, it has provided links to both published versions and major open access repositories, but still does not cover those posted on individual faculty web pages; access to such self-archived non-subscription versions is now provided by a link to Google, where one can find such open access articles.
Through its "cited by" feature, Google Scholar provides access to abstracts of articles that have cited the article being viewed. It is this feature in particular that provides the citation indexing previously only found in Scopus and Web of Knowledge. Through its "Related articles" feature, Google Scholar presents a list of closely related articles, ranked primarily by how similar these articles are to the original result, but also taking into account the relevance of each paper.
Criticism:
Some searchers consider Google Scholar of comparable quality and utility to commercial databases, even though its user-interface (UI) is still in beta. The reviews recognize that its "cited by" feature in particular poses serious competition to Scopus and ISI Web of Knowledge, although it generally returns fewer results than subscription services.
A significant problem with Google Scholar is the secrecy about its coverage. Some publishers do not allow it to crawl their journals. Elsevier journals were not included before mid-2007, when Elsevier began to make most of its ScienceDirect content available to Google Scholar and Google's web search. As of February 2008 the absentees still included the most recent years of the American Chemical Society journals. Google Scholar does not publish a list of scientific journals crawled, and the frequency of its updates is unknown. It is therefore impossible to know how current or exhaustive searches are in Google Scholar. Nonetheless, it allows easy access to published articles without the difficulties encountered in some of the most expensive commercial databases.Google Scholar has problems identifying publications on the arXiv preprint server correctly. Interpunctuation characters in titles produce wrong search results, and authors are assigned to wrong papers, which leads to erroneous additional search results. Some search results are even given without any comprehensible reason. Google Scholar was not developed to aid someone who is seeking out intense medical clinical questions, but was developed to share the basics of what the importance of the topic is.
Guide de GOOGLE SCHOLAR
http://scholar.google.com/ vous aide à trouver de la littérature académique, universitaire et scientifique sur le Web.
Couverture : multidisciplinaire mais le domaine sciences et techniques est beaucoup plus représenté que les sciences sociales et humaines
Sources: ACM, Annual Review, arXiv, HAL, Blackwell, IEEE, Ingenta, Institute of Physic, PubMed, Nature Publishing, Springer, Wiley Interscience, le catalogue de l’INIST, le SUDOC, OCLC Worldcat…
Documents : articles de revues scientifiques, prépublications, résumés, références bibliographiques (Livres, thèses, citations), rapports techniques…
Une Base bibliométrique : Cet outil extrait le nombre de citations pour chaque résultat retourné. Google s’étant largement inspiré du Science Citation Index de l’ISI. Attention ! Ce calcul s’effectue sur sa propre base, il n’est donc pas exhaustif !
Avantages :
Ø Gratuité.
Ø Recherche fédérée sur un corpus « dit » scientifique.
Ø Simplicité d’utilisation.
Ø Augmente la visibilité de la littérature académique.
Ø La recherche par mots-clés en texte intégral.
Ø Identifie les sources des résultats.
Ø Identifie l’impact d’une ressource par son taux de citation.
Ø Se constituer une bibliographie et citer ses sources.
Ø Rechercher, localiser et accéder à une ressource depuis sa bibliothèque.
Limites:
Ø Opacité de l’algorithme et des technologies utilisées.
Ø N’est pas exhaustif ! Couverture réelle inconnue, aucune information sur la période couverte, aucune indication sur le volume disponible.
Ø Ambiguïté de l’interrogation en langage naturel, indexation automatique, ne repose sur aucun langage contrôlé ni thésaurus.
Ø Erreurs dans les résultats (doublons, auteurs…).
Ø Index de citation incomplet.
A utiliser:
Ø Pour une première approche et une recherche non exhaustive sur un sujet.
Ø Pour une recherche croisée, multidisciplinaire.
Ø Pour trouver des ressources en texte intégral, en libre accès.
Ø Pour suivre l’impact scientifique d’une publication sur le web.
Ø Pour trouver un article spécifique dans un journal spécifique.
Ø En complément des bases de données spécialisées.
« Advanced Scholar Search » propose:
Ø Des champs qui remplissent les fonctions des opérateurs booléens AND, NOT, OR.
Ø Un champ pour la recherche d’une expression exacte.
Ø Une recherche par auteur, nom de publication et intervalle de dates.
Ø De sélectionner la recherche du terme dans tout le document ou de la limiter au titre.
Ø De limiter sa recherche de 1 à 7 domaines (Biology, Chemistry…). Attention, fonctionnalitédisponible que depuis l’interface en anglais !
Couverture : multidisciplinaire mais le domaine sciences et techniques est beaucoup plus représenté que les sciences sociales et humaines
Sources: ACM, Annual Review, arXiv, HAL, Blackwell, IEEE, Ingenta, Institute of Physic, PubMed, Nature Publishing, Springer, Wiley Interscience, le catalogue de l’INIST, le SUDOC, OCLC Worldcat…
Documents : articles de revues scientifiques, prépublications, résumés, références bibliographiques (Livres, thèses, citations), rapports techniques…
Une Base bibliométrique : Cet outil extrait le nombre de citations pour chaque résultat retourné. Google s’étant largement inspiré du Science Citation Index de l’ISI. Attention ! Ce calcul s’effectue sur sa propre base, il n’est donc pas exhaustif !
Avantages :
Ø Gratuité.
Ø Recherche fédérée sur un corpus « dit » scientifique.
Ø Simplicité d’utilisation.
Ø Augmente la visibilité de la littérature académique.
Ø La recherche par mots-clés en texte intégral.
Ø Identifie les sources des résultats.
Ø Identifie l’impact d’une ressource par son taux de citation.
Ø Se constituer une bibliographie et citer ses sources.
Ø Rechercher, localiser et accéder à une ressource depuis sa bibliothèque.
Limites:
Ø Opacité de l’algorithme et des technologies utilisées.
Ø N’est pas exhaustif ! Couverture réelle inconnue, aucune information sur la période couverte, aucune indication sur le volume disponible.
Ø Ambiguïté de l’interrogation en langage naturel, indexation automatique, ne repose sur aucun langage contrôlé ni thésaurus.
Ø Erreurs dans les résultats (doublons, auteurs…).
Ø Index de citation incomplet.
A utiliser:
Ø Pour une première approche et une recherche non exhaustive sur un sujet.
Ø Pour une recherche croisée, multidisciplinaire.
Ø Pour trouver des ressources en texte intégral, en libre accès.
Ø Pour suivre l’impact scientifique d’une publication sur le web.
Ø Pour trouver un article spécifique dans un journal spécifique.
Ø En complément des bases de données spécialisées.
« Advanced Scholar Search » propose:
Ø Des champs qui remplissent les fonctions des opérateurs booléens AND, NOT, OR.
Ø Un champ pour la recherche d’une expression exacte.
Ø Une recherche par auteur, nom de publication et intervalle de dates.
Ø De sélectionner la recherche du terme dans tout le document ou de la limiter au titre.
Ø De limiter sa recherche de 1 à 7 domaines (Biology, Chemistry…). Attention, fonctionnalitédisponible que depuis l’interface en anglais !
lundi 1 mars 2010
Network neutrality
Google is a noted supporter of network neutrality. According to Google's Guide to Net Neutrality:
Network neutrality is the principle that Internet users should be in control of what content they view and what applications they use on the Internet. The Internet has operated according to this neutrality principle since its earliest days… Fundamentally, net neutrality is about equal access to the Internet. In our view, the broadband carriers should not be permitted to use their market power to discriminate against competing applications or content. Just as telephone companies are not permitted to tell consumers who they can call or what they can say, broadband carriers should not be allowed to use their market power to control activity online. On February 7, 2006, Vinton Cerf, a co-inventor of the Internet Protocol (IP), and current Vice President and "Chief Internet Evangelist" at Google, in testimony before Congress, said, "allowing broadband carriers to control what people see and do online would fundamentally undermine the principles that have made the Internet such a success.
Network neutrality is the principle that Internet users should be in control of what content they view and what applications they use on the Internet. The Internet has operated according to this neutrality principle since its earliest days… Fundamentally, net neutrality is about equal access to the Internet. In our view, the broadband carriers should not be permitted to use their market power to discriminate against competing applications or content. Just as telephone companies are not permitted to tell consumers who they can call or what they can say, broadband carriers should not be allowed to use their market power to control activity online. On February 7, 2006, Vinton Cerf, a co-inventor of the Internet Protocol (IP), and current Vice President and "Chief Internet Evangelist" at Google, in testimony before Congress, said, "allowing broadband carriers to control what people see and do online would fundamentally undermine the principles that have made the Internet such a success.
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