Welcome to Mathebook.net an online Free Learning website full of fun. This website is fully interactive and will allow kids to practice and learn math with ease.
Our website is designed to help students of different grades, starts from Kindergarten, Elementary, Middle School and High School Math.
The goal of this website is to provide new education tools to teachers, parents and off course students who can benefit from it.
Mathebook.net has Online Tutorials as well as Downloadable pdf tutorials which one can save on computer and use later, even it can be used by teachers for home work purpose, as this pdf is editable and kids can e-mail the homework tutorials by e-mail back to Teachers. By using Downloadable Tutorials one can save the waste of paper and SAVE TREES, so we encourage you to be GREEN, and help mother nature to survive.
Online Tutorials has the score card which allows them to know how may answers were right or wrong. If the kid does not know the answer our intelligent tool will show the correct answer, it’s a learning curve !
Downloadable Tutorials are easy to use, but you will need Acrobat Reader to use this format ( which can be freely downloadable at www.acrobat.com ) One can save the work sheet, even if required take print out or just simply e-mail it to teachers and friends. In our downloadable section you will find several such pdf to download.
I am sure this website will serve and make life easy for kids, but we have not stopped here, we will continuously develop and further enhance the syllabus and will keep adding new features.
If you have a suggestion which can improve the user experience, share with us and we will work to incorporate on this website. That’s our Promise.
Sa fiti iubiti!
Profesorul
08.10.2009
23.06.2009
City information directly on your mobile
City information directly on your mobile
23 June 2009
This month, a start-up company from ESA's Business Incubation Centre launched a new mobile phone service which provides, with the help of satellite and telecommunication technology, location-based information on shopping, entertainment, tourism, and public transportation.
http://www.esa.int/esaCP/SEM74KQORVF_index_0.html
ESA
Sa fiti iubiti!
Constantin NITU
23 June 2009
This month, a start-up company from ESA's Business Incubation Centre launched a new mobile phone service which provides, with the help of satellite and telecommunication technology, location-based information on shopping, entertainment, tourism, and public transportation.
http://www.esa.int/esaCP/SEM74KQORVF_index_0.html
ESA
Sa fiti iubiti!
Constantin NITU
20.06.2009
In 2010 precizia GPS ar putea începe sa scada
In 2010 precizia GPS ar putea începe sa scada
de Adam C. Engst
[Actualizat pentru a clarifica faptul că Mike Craymer pur şi simplu ne-a avertizat de raportul GAO; el nu este responsabil pentru identificarea problemelor cu GPS. -Adam]
Ne-am obişnuit cu toate progresele de folosire a sistemului de pozitionare terestra (Global Positioning System sau GPS), prin intermediul aparatelor iPhone, dispozitivelor de navigare auto, receptoarelor personale GPS sau chiar a ceasurilor cu dispozitive GPS, cum ar fi seria de dispozitive Garmin. GPS-ul a devenit un sistem complet funcţional în decembrie 1993, în 1996 fiind declarat un sistem cu dublă utilizare (militara şi civila) de preşedintele Bill Clinton, iar în anul 2000 fiind abrogata " Disponibilitatea selectiva" pentru a creşte acurateţea in utilizările civile. Sistemul se bazează pe o constelaţie de 24 pana la 32 de sateliţi pe orbite medii in jurul Pământului, dintre care unii sunt in operare de aproape 19 ani. Spre deosebire de alte sisteme de navigaţie prin satelit, GPS serveşte întreaga lume şi este intreţinut de către a Flotila Spatiala 50 a Fortelor Aeriene ale S.U.A. (50 de Air Force Space Wing).
Până în prezent sistemul este destul de bun, dar Mike Craymer de la TidBITS, un geodez care studiaza dimensiunile, forma şi variaţiile temporale ale dimensiunilor Pământului, a avertizat recent printr-un raport despre posibile viitoare probleme privind precizia sistemului GPS. Mike si echipa sa de la Natural Resources Canada utilizeaza foarte mult receptoarele GPS şi tehnici speciale de prelucrare a datelor, pentru a măsura dimensiunile Pamantului, cu o precizie de aproximativ 1 mm pe an, în munca lor de definire şi de menţinere a sistemelor de coordonate folosite în America de Nord şi să contribuie la sistemul global de coordonate utilizat de către GPS (WGS). Trebuie sa atrag atentia ca Mike este foarte interesat de menţinerea GPS la un nivel înalt de precizie.
Problema este că, la sfârşitul lunii aprilie 2009, Accuntability Office din cadrul guvernului SUA a lansat un raport in care îşi exprimă îngrijorarea cu privire la modernizarea şi întreţinerea sistemului GPS de catre Forţele Aeriene. Este necesara înlocuirea şi modernizarea permanenta a sateliţilor, în special cu hardware-ul operational de la bord, care functioneaza de aproape două decenii.
Raportul GAO atrage atenţia asupra problemelor pe care Air Force nu le-a rezolvat inca cu contractorii, de construire şi lansare la termen a sateliţilor GPS conform obiectivelor si costurilor prevazute in program. Unele dintre aceste probleme provin de la metode guvernamentale de achizitie care nu au oferit o suficienta supraveghere, şi la care se adaugă cerinţele de costuri şi de derulare a programului.
GAO stabileşte de asemenea ca o parte din vină o are o serie de fuziuni din industrie (Boeing cumpără Rockwell, Boeing fuziuneaya cu McDonnell Douglas, Boeing cumpără corporaţia de comunicaţii spaţiale şi de afaceri Hughes Electronics), care a dus în mod repetat la mutaţii în lucrul din cadrul GPS şi la pierderea cunoştinţelor lucrătorilor specialişti.
Întârzierile în lansarea de noi sateliţi (următoarea lansare este programată pentru o noiembrie 2009), de aproape 3 ani, ar putea fi problematice în cazul în care se foloseşte hardware mai vechi. GAO a calculat - folosind curbele de fiabilitate pentru fiecare satelit operaţional - faptul că probabilitatea de a menţine o constelaţie de 24 de sateliţi în orbită scade sub 95 de procente în 2010 şi ar putea pica şi mai jos, la 80 la sută în 2011 şi 2012. Şi în cazul în care Air Force nu îşi îndeplineşte obiectivele pentru următoarea generaţie de sateliţi GPS III, probabilitatea scade cu aproximativ 10 la sută în 2017 (sateliţii GPS III au noi facilităţi, inclusiv noi semnale militare şi civile pentru o mai mare precizie, în special în mediile urbane, plus o mai mare putere pentru semnalele de tip civil, în folosul receptoarelor GPS existente).
Chiar şi în cazul în care constelaţia scade sub 24 de sateliţi, aceasta nu înseamnă că serviciile GPS de nu vor fi asigurate. Aceasta înseamnă că nivelul de precizie pentrue utilizatorii militari şi civili este buna, care este de fapt mai mare decât cea promisă,dar se poate degrada semnificativ.
GAO a făcut recomandări pentru rezolvarea problemelor de gestionare a sistemului GPS, mai ales că există o singură autoritate de supraveghere a dezvoltării. Se pare că, în timp ce Air Force se ocupă de sateliţi şi de control la sol, diverse alte ramuri militare care dezvoltă propriile echipamente de utilizare, ducând la actualizarea şi îmbunătăţirea tehnologiei.
O altă soluţie poate fi prin cooperare internaţională. Deşi sistemul GPS este disponibil la nivel mondial, Uniunea Europeană a propus un sistem global de navigaţie prin sateliţi numit Galileo, care va fi complet funcţionanil în 2013. Galileo este destinat în mare parte pentru utilizare civilă, care să nu depindă de capriciile guvernului SUA pe timp de conflict militar, deşi un compromis face posibilă din 2004 blocarea de către Statele Unite a frecvenţelor Galileo, precum şi interoperabilitatea celor două sisteme în viitor. Galileo are si scopul de a oferi o precizie mai mare decât sistemul GPS şi, atunci când este combinat cu următoarea generaţie de sateliţi GPS III, ar putea îmbunătăţi precizia mult mai mult.
Rusia şi China au, de asemenea, sisteme de navigaţie prin satelit, şi au existat discuţii cu guvernul rus pentru a face compatibil sistemul rusesc GLONASS cu ambele sisteme, GPS şi Galileo. Nu s-a publicat nimic despre aceste discuţii, dar în 2007, GLONASS a fost deschis pentru utilizare civilă. GLONASS are o istorie controversată, devenind funcţional online în 1995, dar care se încadrează rapid într-o situaţie proastă din cauza unor probleme economice. Rusia a restabilit sistemul în 2001, cu o constelaţie de 24 de sateliţi (necesari pentru acoperire la nivel global) în funcţiune până în anul 2010.
Revenind la sistemul american GPS, serviciile LBS (servicii bazate pe localizare) au devenit importante pentru societate prin eliminarea disponibilităţii selective, astfel vă puteţi imagina cât de importante devin aceste capabilităţi în următorii zece ani.
Personal, nu pot să îmi imaginez că Air Force ar lăsa să scadă precizia GPS, având în vedere mai ales încrederea militarilor în el, de la a-şi determina poziţia la descoperirea obiectivelor pe timp de noapte, pentru direcţionarea precisă a rachetelor şi a altor muniţii ghidate cu mare precizie. În cazul în care sugestiile GAO (cu care Departamentul Apărării este de acord), nu rezolvă problemele cu care se confruntă de sistemul GPS, Air Force va avea nevoie de şi mai multe fonduri financiare.
(traducere, NC)
de Adam C. Engst
[Actualizat pentru a clarifica faptul că Mike Craymer pur şi simplu ne-a avertizat de raportul GAO; el nu este responsabil pentru identificarea problemelor cu GPS. -Adam]
Ne-am obişnuit cu toate progresele de folosire a sistemului de pozitionare terestra (Global Positioning System sau GPS), prin intermediul aparatelor iPhone, dispozitivelor de navigare auto, receptoarelor personale GPS sau chiar a ceasurilor cu dispozitive GPS, cum ar fi seria de dispozitive Garmin. GPS-ul a devenit un sistem complet funcţional în decembrie 1993, în 1996 fiind declarat un sistem cu dublă utilizare (militara şi civila) de preşedintele Bill Clinton, iar în anul 2000 fiind abrogata " Disponibilitatea selectiva" pentru a creşte acurateţea in utilizările civile. Sistemul se bazează pe o constelaţie de 24 pana la 32 de sateliţi pe orbite medii in jurul Pământului, dintre care unii sunt in operare de aproape 19 ani. Spre deosebire de alte sisteme de navigaţie prin satelit, GPS serveşte întreaga lume şi este intreţinut de către a Flotila Spatiala 50 a Fortelor Aeriene ale S.U.A. (50 de Air Force Space Wing).
Până în prezent sistemul este destul de bun, dar Mike Craymer de la TidBITS, un geodez care studiaza dimensiunile, forma şi variaţiile temporale ale dimensiunilor Pământului, a avertizat recent printr-un raport despre posibile viitoare probleme privind precizia sistemului GPS. Mike si echipa sa de la Natural Resources Canada utilizeaza foarte mult receptoarele GPS şi tehnici speciale de prelucrare a datelor, pentru a măsura dimensiunile Pamantului, cu o precizie de aproximativ 1 mm pe an, în munca lor de definire şi de menţinere a sistemelor de coordonate folosite în America de Nord şi să contribuie la sistemul global de coordonate utilizat de către GPS (WGS). Trebuie sa atrag atentia ca Mike este foarte interesat de menţinerea GPS la un nivel înalt de precizie.
Problema este că, la sfârşitul lunii aprilie 2009, Accuntability Office din cadrul guvernului SUA a lansat un raport in care îşi exprimă îngrijorarea cu privire la modernizarea şi întreţinerea sistemului GPS de catre Forţele Aeriene. Este necesara înlocuirea şi modernizarea permanenta a sateliţilor, în special cu hardware-ul operational de la bord, care functioneaza de aproape două decenii.
Raportul GAO atrage atenţia asupra problemelor pe care Air Force nu le-a rezolvat inca cu contractorii, de construire şi lansare la termen a sateliţilor GPS conform obiectivelor si costurilor prevazute in program. Unele dintre aceste probleme provin de la metode guvernamentale de achizitie care nu au oferit o suficienta supraveghere, şi la care se adaugă cerinţele de costuri şi de derulare a programului.
GAO stabileşte de asemenea ca o parte din vină o are o serie de fuziuni din industrie (Boeing cumpără Rockwell, Boeing fuziuneaya cu McDonnell Douglas, Boeing cumpără corporaţia de comunicaţii spaţiale şi de afaceri Hughes Electronics), care a dus în mod repetat la mutaţii în lucrul din cadrul GPS şi la pierderea cunoştinţelor lucrătorilor specialişti.
Întârzierile în lansarea de noi sateliţi (următoarea lansare este programată pentru o noiembrie 2009), de aproape 3 ani, ar putea fi problematice în cazul în care se foloseşte hardware mai vechi. GAO a calculat - folosind curbele de fiabilitate pentru fiecare satelit operaţional - faptul că probabilitatea de a menţine o constelaţie de 24 de sateliţi în orbită scade sub 95 de procente în 2010 şi ar putea pica şi mai jos, la 80 la sută în 2011 şi 2012. Şi în cazul în care Air Force nu îşi îndeplineşte obiectivele pentru următoarea generaţie de sateliţi GPS III, probabilitatea scade cu aproximativ 10 la sută în 2017 (sateliţii GPS III au noi facilităţi, inclusiv noi semnale militare şi civile pentru o mai mare precizie, în special în mediile urbane, plus o mai mare putere pentru semnalele de tip civil, în folosul receptoarelor GPS existente).
Chiar şi în cazul în care constelaţia scade sub 24 de sateliţi, aceasta nu înseamnă că serviciile GPS de nu vor fi asigurate. Aceasta înseamnă că nivelul de precizie pentrue utilizatorii militari şi civili este buna, care este de fapt mai mare decât cea promisă,dar se poate degrada semnificativ.
GAO a făcut recomandări pentru rezolvarea problemelor de gestionare a sistemului GPS, mai ales că există o singură autoritate de supraveghere a dezvoltării. Se pare că, în timp ce Air Force se ocupă de sateliţi şi de control la sol, diverse alte ramuri militare care dezvoltă propriile echipamente de utilizare, ducând la actualizarea şi îmbunătăţirea tehnologiei.
O altă soluţie poate fi prin cooperare internaţională. Deşi sistemul GPS este disponibil la nivel mondial, Uniunea Europeană a propus un sistem global de navigaţie prin sateliţi numit Galileo, care va fi complet funcţionanil în 2013. Galileo este destinat în mare parte pentru utilizare civilă, care să nu depindă de capriciile guvernului SUA pe timp de conflict militar, deşi un compromis face posibilă din 2004 blocarea de către Statele Unite a frecvenţelor Galileo, precum şi interoperabilitatea celor două sisteme în viitor. Galileo are si scopul de a oferi o precizie mai mare decât sistemul GPS şi, atunci când este combinat cu următoarea generaţie de sateliţi GPS III, ar putea îmbunătăţi precizia mult mai mult.
Rusia şi China au, de asemenea, sisteme de navigaţie prin satelit, şi au existat discuţii cu guvernul rus pentru a face compatibil sistemul rusesc GLONASS cu ambele sisteme, GPS şi Galileo. Nu s-a publicat nimic despre aceste discuţii, dar în 2007, GLONASS a fost deschis pentru utilizare civilă. GLONASS are o istorie controversată, devenind funcţional online în 1995, dar care se încadrează rapid într-o situaţie proastă din cauza unor probleme economice. Rusia a restabilit sistemul în 2001, cu o constelaţie de 24 de sateliţi (necesari pentru acoperire la nivel global) în funcţiune până în anul 2010.
Revenind la sistemul american GPS, serviciile LBS (servicii bazate pe localizare) au devenit importante pentru societate prin eliminarea disponibilităţii selective, astfel vă puteţi imagina cât de importante devin aceste capabilităţi în următorii zece ani.
Personal, nu pot să îmi imaginez că Air Force ar lăsa să scadă precizia GPS, având în vedere mai ales încrederea militarilor în el, de la a-şi determina poziţia la descoperirea obiectivelor pe timp de noapte, pentru direcţionarea precisă a rachetelor şi a altor muniţii ghidate cu mare precizie. În cazul în care sugestiile GAO (cu care Departamentul Apărării este de acord), nu rezolvă problemele cu care se confruntă de sistemul GPS, Air Force va avea nevoie de şi mai multe fonduri financiare.
(traducere, NC)
Точность GPS cбрасывание может начаться в 2010 году
Точность GPS cбрасывание может начаться в 2010 году
Адам E.
[Изменения с целью уточнить, что Майк KpaйMep просто предупредил нас к ГАО доклада, он не отвечает за выявление проблемы с GPS.]
Мы все привыкли к использованию системы глобального позиционирования, или GPS, независимо от того, через наш iPhones, автомобильных навигационных устройств, портативных GPS подразделения или даже смотреть на основе устройств, как Garmin Ветхозаветный серии. GPS-системы пошли на полную мощность в декабре 1993 года был объявлен двойного назначения (военного и гражданского) система президентом Биллом Клинтоном в 1996 году, а в 2000 году "Селективная наличие" удаляются для увеличения точности для использования в гражданских целях. Она опирается на созвездие между 24 и 32 средних орбитах вокруг Земли спутников, некоторые из которых работают почти 19 лет. В отличие от других национальных спутниковых навигационных систем GPS служит весь мир и поддерживается Соединенными Штатами ВВС 50 космических крыла.
Так далеко, так что хорошо, но TidBITS читатель Майк Craymer, а геодезистом, кто изучает размер, форму и временные колебания Земли, недавно предупредил меня доклад о возможных будущих проблем с точность GPS-системы. Майк и его команда в Министерство природных ресурсов Канады используют очень высокого класса GPS приемники и специальных методов обработки данных для измерения движения Земли с точностью около 1 мм в год в своей работе определения и поддержания систем координат, используемых в Северной Америке и вклад в глобальную систему координат, используемых GPS. Излишне говорить о том, что Майку очень заинтересованы в GPS поддержание высокого уровня точности.
Проблема заключается в том, что в конце апреля 2009 года, правительство США отчетности Управления выпустила доклад, выразил озабоченность по поводу военно-воздушные силы в модернизации и поддержании в системе GPS. Постоянная замена и модернизация спутников является необходимым, особенно в том, что аппаратные средства, которые уже действуют в пространстве на протяжении почти двух десятилетий.
ГАО В докладе обращается внимание на проблемы, с которыми ВВС имеет в работе с подрядчиками для создания и запуска спутников GPS в стоимости и графике целей. Некоторые из этих проблем связаны с приобретением государственных методов, которые не обеспечивают достаточный контроль, и добавил, что требования, в результате стоимость и график перерасход.
В ГАО также лежит часть вины на серии слияний промышленности (Боинг покупке Rockwell, Boeing слиянии с McDonnell Douglas, Boeing покупке Хьюз Electronics Corporation космической связи и предприятий), в результате перехода на работу GPS неоднократно и потерять знающих работников.
Задержки в создании новых спутников - следующий намечен на ноябрь 2009 год запуска, почти 3-х лет поздно - может оказаться проблематичным, если на старых аппаратных средств, не начинает. В ГАО рассчитал - надежность с помощью кривых для каждой оперативной спутниковой - о том, что вероятность сохранения 24 спутников на орбите падает ниже 95 процентов в 2010 году, и падение может как низкий, как 80 процентов в 2011 и 2012 годах. И если ВВС не отвечает его цели для следующего поколения спутников GPS III, вероятность падает до примерно 10 процентов в 2017. (GPS-III спутников принесет с собой новые возможности, в том числе новые военные и гражданские сигналы, для большей точности, особенно в городских условиях, а также увеличению мощности для нынешних гражданских сигналов, которые будут способствовать существующие GPS приемниками.)
Даже если спутников падает ниже 24 спутников, это не означает, что служба GPS не удастся вообще. Это означает, что уровень точности, что и военные и гражданские пользователи уже привыкли к, - которые на самом деле выше, чем обещали - могут значительно ухудшить.
В ГАО сделала рекомендации по решению проблем, по его мнению, в работе с GPS-системы, прежде всего единый орган для контроля за развитием. Видимо, в то время как ВВС занимается спутников и наземного контроля, различных других отраслях военной разрабатывать собственные пользователь оборудования, который обеспечивает координацию проблем технологии обновляется и совершенствуется.
Другим решением может быть в форме международного сотрудничества. Несмотря на то, что система GPS доступна во всем мире, Европейский союз имеет предлагаемой глобальной навигационной спутниковой системы "Галилео" в работах, должен вступить в сети в 2013 году. "Галилео" на то, чтобы быть в основном гражданские системы, которая будет действовать не по прихоти правительства США во время военного конфликта, хотя в 2004 компромисса дает возможность как для США, чтобы заблокировать "Галилео" и частоты для двух систем, взаимодействовать в будущем. "Галилео" также направлен на обеспечение большей точности, чем GPS, а в сочетании со следующего поколения спутников GPS III, могут улучшить точность даже дальше.
Россия и Китай также спутниковых навигационных систем, и там были переговоры с российским правительством о внесении Российской GLONOSS системы, совместимой с GPS и Галилео. Никаких официальных объявлений в результате этих переговоров, но в 2007 году, GLONASS была открыта для гражданского использования. GLONASS имеет изменчивая история, предстоящий в сети в 1995 году, но входящих в упадок вскоре после этого, в связи с проблемами российской экономики. Россия привержена восстановления системы в 2001 году, с полным 24-спутников (необходимые для глобального охвата) в эксплуатацию к 2010 году.
С точки зрения нормальных людей в Соединенных Штатах, то ничего, кроме подождать и посмотреть, и если возможность представляет себе, убедиться, что нашим избранным представителям известно об этой ситуации. Если вы думаете о том, каким важным GPS-услуг на базе стали для общества в целом в период после Селективный Наличие был отменен, вы можете себе представить, насколько важно эти возможности станут в ближайшие десятилетия.
Лично я не могу себе представить, что военно-воздушные силы позволит GPS точность падения, особенно учитывая военную зависимость от его за все, начиная от солдат, помогая найти свои цели в темное время суток к точной ориентации ракет и другие высокоточные боеприпасы. Если ГАО предложения (с которой министерство обороны согласна) не решают проблем, с которыми сталкивается система GPS, военно-воздушных сил может закончиться расходы намного больше денег на исправление этой системы на временной основе.
(traducere NC)
Адам E.
[Изменения с целью уточнить, что Майк KpaйMep просто предупредил нас к ГАО доклада, он не отвечает за выявление проблемы с GPS.]
Мы все привыкли к использованию системы глобального позиционирования, или GPS, независимо от того, через наш iPhones, автомобильных навигационных устройств, портативных GPS подразделения или даже смотреть на основе устройств, как Garmin Ветхозаветный серии. GPS-системы пошли на полную мощность в декабре 1993 года был объявлен двойного назначения (военного и гражданского) система президентом Биллом Клинтоном в 1996 году, а в 2000 году "Селективная наличие" удаляются для увеличения точности для использования в гражданских целях. Она опирается на созвездие между 24 и 32 средних орбитах вокруг Земли спутников, некоторые из которых работают почти 19 лет. В отличие от других национальных спутниковых навигационных систем GPS служит весь мир и поддерживается Соединенными Штатами ВВС 50 космических крыла.
Так далеко, так что хорошо, но TidBITS читатель Майк Craymer, а геодезистом, кто изучает размер, форму и временные колебания Земли, недавно предупредил меня доклад о возможных будущих проблем с точность GPS-системы. Майк и его команда в Министерство природных ресурсов Канады используют очень высокого класса GPS приемники и специальных методов обработки данных для измерения движения Земли с точностью около 1 мм в год в своей работе определения и поддержания систем координат, используемых в Северной Америке и вклад в глобальную систему координат, используемых GPS. Излишне говорить о том, что Майку очень заинтересованы в GPS поддержание высокого уровня точности.
Проблема заключается в том, что в конце апреля 2009 года, правительство США отчетности Управления выпустила доклад, выразил озабоченность по поводу военно-воздушные силы в модернизации и поддержании в системе GPS. Постоянная замена и модернизация спутников является необходимым, особенно в том, что аппаратные средства, которые уже действуют в пространстве на протяжении почти двух десятилетий.
ГАО В докладе обращается внимание на проблемы, с которыми ВВС имеет в работе с подрядчиками для создания и запуска спутников GPS в стоимости и графике целей. Некоторые из этих проблем связаны с приобретением государственных методов, которые не обеспечивают достаточный контроль, и добавил, что требования, в результате стоимость и график перерасход.
В ГАО также лежит часть вины на серии слияний промышленности (Боинг покупке Rockwell, Boeing слиянии с McDonnell Douglas, Boeing покупке Хьюз Electronics Corporation космической связи и предприятий), в результате перехода на работу GPS неоднократно и потерять знающих работников.
Задержки в создании новых спутников - следующий намечен на ноябрь 2009 год запуска, почти 3-х лет поздно - может оказаться проблематичным, если на старых аппаратных средств, не начинает. В ГАО рассчитал - надежность с помощью кривых для каждой оперативной спутниковой - о том, что вероятность сохранения 24 спутников на орбите падает ниже 95 процентов в 2010 году, и падение может как низкий, как 80 процентов в 2011 и 2012 годах. И если ВВС не отвечает его цели для следующего поколения спутников GPS III, вероятность падает до примерно 10 процентов в 2017. (GPS-III спутников принесет с собой новые возможности, в том числе новые военные и гражданские сигналы, для большей точности, особенно в городских условиях, а также увеличению мощности для нынешних гражданских сигналов, которые будут способствовать существующие GPS приемниками.)
Даже если спутников падает ниже 24 спутников, это не означает, что служба GPS не удастся вообще. Это означает, что уровень точности, что и военные и гражданские пользователи уже привыкли к, - которые на самом деле выше, чем обещали - могут значительно ухудшить.
В ГАО сделала рекомендации по решению проблем, по его мнению, в работе с GPS-системы, прежде всего единый орган для контроля за развитием. Видимо, в то время как ВВС занимается спутников и наземного контроля, различных других отраслях военной разрабатывать собственные пользователь оборудования, который обеспечивает координацию проблем технологии обновляется и совершенствуется.
Другим решением может быть в форме международного сотрудничества. Несмотря на то, что система GPS доступна во всем мире, Европейский союз имеет предлагаемой глобальной навигационной спутниковой системы "Галилео" в работах, должен вступить в сети в 2013 году. "Галилео" на то, чтобы быть в основном гражданские системы, которая будет действовать не по прихоти правительства США во время военного конфликта, хотя в 2004 компромисса дает возможность как для США, чтобы заблокировать "Галилео" и частоты для двух систем, взаимодействовать в будущем. "Галилео" также направлен на обеспечение большей точности, чем GPS, а в сочетании со следующего поколения спутников GPS III, могут улучшить точность даже дальше.
Россия и Китай также спутниковых навигационных систем, и там были переговоры с российским правительством о внесении Российской GLONOSS системы, совместимой с GPS и Галилео. Никаких официальных объявлений в результате этих переговоров, но в 2007 году, GLONASS была открыта для гражданского использования. GLONASS имеет изменчивая история, предстоящий в сети в 1995 году, но входящих в упадок вскоре после этого, в связи с проблемами российской экономики. Россия привержена восстановления системы в 2001 году, с полным 24-спутников (необходимые для глобального охвата) в эксплуатацию к 2010 году.
С точки зрения нормальных людей в Соединенных Штатах, то ничего, кроме подождать и посмотреть, и если возможность представляет себе, убедиться, что нашим избранным представителям известно об этой ситуации. Если вы думаете о том, каким важным GPS-услуг на базе стали для общества в целом в период после Селективный Наличие был отменен, вы можете себе представить, насколько важно эти возможности станут в ближайшие десятилетия.
Лично я не могу себе представить, что военно-воздушные силы позволит GPS точность падения, особенно учитывая военную зависимость от его за все, начиная от солдат, помогая найти свои цели в темное время суток к точной ориентации ракет и другие высокоточные боеприпасы. Если ГАО предложения (с которой министерство обороны согласна) не решают проблем, с которыми сталкивается система GPS, военно-воздушных сил может закончиться расходы намного больше денег на исправление этой системы на временной основе.
(traducere NC)
GPS Accuracy Could Start Dropping in 2010
GPS Accuracy Could Start Dropping in 2010
by Adam C. Engst
[Updated to clarify that Mike Craymer merely alerted us to the GAO report; he's not responsible for identifying the problems with GPS. -Adam]
We've all become accustomed to using the Global Positioning System, or GPS, whether via our iPhones, car navigation devices, handheld GPS units, or even watch-based devices like the Garmin Forerunner series. The GPS system went into full operation in December of 1993, was declared a dual-use (military and civilian) system by President Bill Clinton in 1996, and in 2000 had "Selective Availability" removed to increase accuracy for civilian uses. It relies on a constellation of between 24 and 32 medium Earth orbit satellites, some of which have been operating for nearly 19 years. Unlike other national satellite navigation systems, GPS serves the entire world and is maintained by the United States Air Force 50th Space Wing.
So far, so good, but TidBITS reader Mike Craymer, a geodesist who studies the size, shape and temporal variations of the Earth, recently alerted me to a report about a possible future problem with the accuracy of the GPS system. Mike and his team at Natural Resources Canada use very high-end GPS receivers and special data processing techniques to measure the motions of the Earth with an accuracy of about 1 mm per year in their work defining and maintaining the coordinate systems used in North America and in contributing to the global coordinate system used by GPS. Needless to say, Mike is very interested in GPS maintaining its high level of accuracy.
The problem is that, at the end of April 2009, the U.S. Government Accountability Office released a report expressing concern about the Air Force's modernization and maintenance of the GPS system. Constant replacement and upgrading of satellites is necessary, especially with hardware that's been operating in space for almost two decades.
The GAO's report draws attention to problems that the Air Force has had in working with contractors to build and launch GPS satellites within cost and schedule goals. Some of the problems stem from government acquisition methods that didn't provide for enough oversight, and added requirements that resulted in cost and schedule overruns.
The GAO also lays some of the blame on a series of industry mergers (Boeing buying Rockwell, Boeing merging with McDonnell Douglas, Boeing buying Hughes Electronics Corporation's space and communications businesses) that resulted in moving the GPS work repeatedly and losing knowledgeable workers.
Delays in launching new satellites - the next one is scheduled for a November 2009 launch, almost 3 years late - could be problematic if the older hardware starts failing. The GAO has calculated - using reliability curves for each operational satellite - that the probability of keeping a 24-satellite constellation in orbit drops below 95 percent in 2010, and could drop as low as 80 percent in 2011 and 2012. And if the Air Force doesn't meet its goals for the next-generation GPS III satellites, the probability drops to around 10 percent in 2017. (The GPS III satellites bring with them new features, including new military and civilian signals for greater accuracy, particularly in urban environments, plus higher power for current civilian signals, which will help existing GPS receivers.)
Even if the satellite constellation drops below 24 satellites, that doesn't mean that GPS service will fail altogether. It does mean that the level of accuracy that both military and civilian users have become accustomed to - which is actually higher than promised - may degrade significantly.
The GAO has made recommendations for addressing the problems it found in the handling of the GPS system, most notably a single authority to oversee development. Apparently, while the Air Force is in charge of the satellites and ground control, various other branches of the military develop their own user equipment, which makes for coordination problems as the technology is updated and improved.
Another solution may come in the form of international cooperation. Although the GPS system is available worldwide, the European Union has a proposed global navigation satellite system called Galileo in the works, due to come online in 2013. Galileo is intended to be a largely civilian system that wouldn't operate at the whim of the U.S. government in time of military conflict, although a 2004 compromise makes it possible both for the United States to block the Galileo frequencies and for the two systems to interoperate in the future. Galileo also aims to provide greater accuracy than GPS, and when combined with the next-generation GPS III satellites, could improve accuracy even further.
Russia and China also have satellite navigation systems, and there have been discussions with the Russian government about making the Russian GLONASS system compatible with both GPS and Galileo. No formal announcement has emerged from those talks, but in 2007, GLONASS was opened up for civilian use. GLONOSS has a checkered history, coming online in 1995 but falling into disrepair soon after, due to Russian economic troubles. Russia committed to restoring the system in 2001, with a full 24-satellite constellation (necessary for global coverage) in operation by 2010.
From the standpoint of normal people in the United States, there's nothing to do except wait and watch, and, if the opportunity presents itself, make sure our elected representatives are aware of the situation. If you think about how essential GPS-based services have become to society at large in the years since Selective Availability was abolished, you can imagine how much more important those capabilities will become in the next decade.
Personally, I can't imagine that the Air Force would let GPS accuracy drop, especially given the military's reliance on it for everything ranging from helping soldiers find their objectives in the dark to accurate targeting of missiles and other precision-guided munitions. If the GAO's suggestions (with which the Department of Defense agrees) don't resolve the problems faced by the GPS system, the Air Force may end up spending far more money to patch the system on an interim basis.
by Adam C. Engst
[Updated to clarify that Mike Craymer merely alerted us to the GAO report; he's not responsible for identifying the problems with GPS. -Adam]
We've all become accustomed to using the Global Positioning System, or GPS, whether via our iPhones, car navigation devices, handheld GPS units, or even watch-based devices like the Garmin Forerunner series. The GPS system went into full operation in December of 1993, was declared a dual-use (military and civilian) system by President Bill Clinton in 1996, and in 2000 had "Selective Availability" removed to increase accuracy for civilian uses. It relies on a constellation of between 24 and 32 medium Earth orbit satellites, some of which have been operating for nearly 19 years. Unlike other national satellite navigation systems, GPS serves the entire world and is maintained by the United States Air Force 50th Space Wing.
So far, so good, but TidBITS reader Mike Craymer, a geodesist who studies the size, shape and temporal variations of the Earth, recently alerted me to a report about a possible future problem with the accuracy of the GPS system. Mike and his team at Natural Resources Canada use very high-end GPS receivers and special data processing techniques to measure the motions of the Earth with an accuracy of about 1 mm per year in their work defining and maintaining the coordinate systems used in North America and in contributing to the global coordinate system used by GPS. Needless to say, Mike is very interested in GPS maintaining its high level of accuracy.
The problem is that, at the end of April 2009, the U.S. Government Accountability Office released a report expressing concern about the Air Force's modernization and maintenance of the GPS system. Constant replacement and upgrading of satellites is necessary, especially with hardware that's been operating in space for almost two decades.
The GAO's report draws attention to problems that the Air Force has had in working with contractors to build and launch GPS satellites within cost and schedule goals. Some of the problems stem from government acquisition methods that didn't provide for enough oversight, and added requirements that resulted in cost and schedule overruns.
The GAO also lays some of the blame on a series of industry mergers (Boeing buying Rockwell, Boeing merging with McDonnell Douglas, Boeing buying Hughes Electronics Corporation's space and communications businesses) that resulted in moving the GPS work repeatedly and losing knowledgeable workers.
Delays in launching new satellites - the next one is scheduled for a November 2009 launch, almost 3 years late - could be problematic if the older hardware starts failing. The GAO has calculated - using reliability curves for each operational satellite - that the probability of keeping a 24-satellite constellation in orbit drops below 95 percent in 2010, and could drop as low as 80 percent in 2011 and 2012. And if the Air Force doesn't meet its goals for the next-generation GPS III satellites, the probability drops to around 10 percent in 2017. (The GPS III satellites bring with them new features, including new military and civilian signals for greater accuracy, particularly in urban environments, plus higher power for current civilian signals, which will help existing GPS receivers.)
Even if the satellite constellation drops below 24 satellites, that doesn't mean that GPS service will fail altogether. It does mean that the level of accuracy that both military and civilian users have become accustomed to - which is actually higher than promised - may degrade significantly.
The GAO has made recommendations for addressing the problems it found in the handling of the GPS system, most notably a single authority to oversee development. Apparently, while the Air Force is in charge of the satellites and ground control, various other branches of the military develop their own user equipment, which makes for coordination problems as the technology is updated and improved.
Another solution may come in the form of international cooperation. Although the GPS system is available worldwide, the European Union has a proposed global navigation satellite system called Galileo in the works, due to come online in 2013. Galileo is intended to be a largely civilian system that wouldn't operate at the whim of the U.S. government in time of military conflict, although a 2004 compromise makes it possible both for the United States to block the Galileo frequencies and for the two systems to interoperate in the future. Galileo also aims to provide greater accuracy than GPS, and when combined with the next-generation GPS III satellites, could improve accuracy even further.
Russia and China also have satellite navigation systems, and there have been discussions with the Russian government about making the Russian GLONASS system compatible with both GPS and Galileo. No formal announcement has emerged from those talks, but in 2007, GLONASS was opened up for civilian use. GLONOSS has a checkered history, coming online in 1995 but falling into disrepair soon after, due to Russian economic troubles. Russia committed to restoring the system in 2001, with a full 24-satellite constellation (necessary for global coverage) in operation by 2010.
From the standpoint of normal people in the United States, there's nothing to do except wait and watch, and, if the opportunity presents itself, make sure our elected representatives are aware of the situation. If you think about how essential GPS-based services have become to society at large in the years since Selective Availability was abolished, you can imagine how much more important those capabilities will become in the next decade.
Personally, I can't imagine that the Air Force would let GPS accuracy drop, especially given the military's reliance on it for everything ranging from helping soldiers find their objectives in the dark to accurate targeting of missiles and other precision-guided munitions. If the GAO's suggestions (with which the Department of Defense agrees) don't resolve the problems faced by the GPS system, the Air Force may end up spending far more money to patch the system on an interim basis.
29.05.2009
IRIDIUM Networks
GlobalTrack G200R IRIDIUM GPS Tracking System
Integrate both gsm/gprs and IRIDIUM dual radio system in one device
Very low latency time,send data from anywhere in the world in few seconds by IRIDIUM
IRIDIUM system support 66 satellites, G200R can work in high density city ,jungles and marines
Compare to other signle satellite system, IRIDIUM system can receive signal in all directions
Very low GPS message air time price, the cost will be lower than gsm SMS
Operate at 1.6G radio band frequency,G200R can be installed and tracking aircrafts
Support live video and fuel level real time monitoring
Worldwide vehice tracking web service with GlobalTrack WebMap with GOOGLE EARTH
Accessories include Camera ,Fuel level Sensor,Temperature Sensor,Vibrations sensor,G-sensor,Small Printer
Introduction to IRIDIUM Networks
The Iridium System is a satellite-based, wireless communications network providing a robust suite of Voice and Data services to virtually any destination anywhere on earth.
With 66 satellites forming a cross-linked grid above the Earth, the Iridium system is the first low-earth orbiting system for telephone service. Only 780km (450 miles) high, these satellites work different from those at a much higher orbit (26,000km) in two major ways. First they're closes enough to receive the signals of a handheld device; and second, they act like cellular towers in the sky - where wireless signals can move overhead instead of through ground based cells.
Frequency Bands
Telephone & Messaging 1616-1625.5 MHz,L-band
Intersatellite Links 23.18-23.38 GHz, Ka-band
Ground Segment Links
Downlinks 19.4-19.6 GHz, Ka-band
Uplinks 29.1-29.3 GHz, Ka-band
Integrate both gsm/gprs and IRIDIUM dual radio system in one device
Very low latency time,send data from anywhere in the world in few seconds by IRIDIUM
IRIDIUM system support 66 satellites, G200R can work in high density city ,jungles and marines
Compare to other signle satellite system, IRIDIUM system can receive signal in all directions
Very low GPS message air time price, the cost will be lower than gsm SMS
Operate at 1.6G radio band frequency,G200R can be installed and tracking aircrafts
Support live video and fuel level real time monitoring
Worldwide vehice tracking web service with GlobalTrack WebMap with GOOGLE EARTH
Accessories include Camera ,Fuel level Sensor,Temperature Sensor,Vibrations sensor,G-sensor,Small Printer
Introduction to IRIDIUM Networks
The Iridium System is a satellite-based, wireless communications network providing a robust suite of Voice and Data services to virtually any destination anywhere on earth.
With 66 satellites forming a cross-linked grid above the Earth, the Iridium system is the first low-earth orbiting system for telephone service. Only 780km (450 miles) high, these satellites work different from those at a much higher orbit (26,000km) in two major ways. First they're closes enough to receive the signals of a handheld device; and second, they act like cellular towers in the sky - where wireless signals can move overhead instead of through ground based cells.
Frequency Bands
Telephone & Messaging 1616-1625.5 MHz,L-band
Intersatellite Links 23.18-23.38 GHz, Ka-band
Ground Segment Links
Downlinks 19.4-19.6 GHz, Ka-band
Uplinks 29.1-29.3 GHz, Ka-band
28.05.2009
How to create websites that use Google Maps/Earth to map information in a back end database
Professor Nitu,
I am happy to be named a friend! I hope you and your students find this work useful. Sometime later this year I will release code on how to create websites that use Google Maps/Earth to map information in a back end database. You can see an example at http://ctasgis02.psur.utk.edu/tokml.
Hopefully, I will complete an e-book on how to program for KML mapping engines, both desktop and web based.
Cheers,
Bruce Ralston
I am happy to be named a friend! I hope you and your students find this work useful. Sometime later this year I will release code on how to create websites that use Google Maps/Earth to map information in a back end database. You can see an example at http://ctasgis02.psur.utk.edu/tokml.
Hopefully, I will complete an e-book on how to program for KML mapping engines, both desktop and web based.
Cheers,
Bruce Ralston
27.05.2009
AFF Mapper - programe freeware
My colleague geogprof writes "I have released a program called AFF Mapper. This is
a Windows based package that was specifically designed for creating KML based mapping files from TIGER shapes and tables available from the Census Bureau's American FactFinder web page. While it was designed for these files, it can be used to create KML files for other shapes (that are in decimal degrees with NAD83 or WGS 84) and external attribute files. The resulting KML files can be viewed in several free mapping packages such as Google Earth and ArcGIS Explorer. To download a copy of
the program and the user manual, go to
[1]http://tnatlas.geog.utk.edu/downloadfree.htm. This is freeware, copy till you drop. Source code will be released at a later date." See also related stories below.
Link:
1. http://tnatlas.geog.utk.edu/downloadfree.htm
Sa fiti iubiti!
a Windows based package that was specifically designed for creating KML based mapping files from TIGER shapes and tables available from the Census Bureau's American FactFinder web page. While it was designed for these files, it can be used to create KML files for other shapes (that are in decimal degrees with NAD83 or WGS 84) and external attribute files. The resulting KML files can be viewed in several free mapping packages such as Google Earth and ArcGIS Explorer. To download a copy of
the program and the user manual, go to
[1]http://tnatlas.geog.utk.edu/downloadfree.htm. This is freeware, copy till you drop. Source code will be released at a later date." See also related stories below.
Link:
1. http://tnatlas.geog.utk.edu/downloadfree.htm
Sa fiti iubiti!
26.05.2009
10 Thoughts for Someone Contemplating a Geospatial Career
by Jeff Thurston
All things change over time. This includes geographic information systems (GIS), computer aided design (CAD), global positioning systems (GPS), remote sensing, surveying and a wide array of geospatial technologies and applications. What I would have said to someone embarking on a spatially related career ten years ago would be different than what I would say today. Some things have changed dramatically, others in new ways and some minimally. Here is what I’d say today to someone contemplating a geo-career, in no particular order.
1) GNSS is an integration of GPS satellite systems. You can actually use a GNSS receiver today and get excellent results. If you thought one GPS was good, then 2 or 3 are going to really open your eyes. GNSS is going to revolutionise all we know about location based services. It will create a whole new class of professionals interested in position and navigation.
2) GIS is the de facto integrator of spatial information. Focus on it. Learn how all other technologies are spokes leading toward its integration. If you understand it as existing on a level equivalent to business systems then you will have the power to strategically drive new business applications and directions.
3) 3D is the future. It is not just about data though, it is also about visualisation. Start using the phrase ‘elegant solution.’ Pay attention to the concept of ‘Digital Cities.’
4) Sensing will increasing play a role that is supported through legislation. Data matters and numbers matter. Carbon credits become a currency, for example, and geotechnologies the stock exchange. I can’t say enough about understanding monitoring and it’s linkage to geospatial technologies. The current economic crisis will eventually lead to transparency and more of it.
5) Our concept of time is not well defined in spatial technologies. We can do scheduling well, but being able to understand ‘change over time’ is becoming more meaningful. It also relates closely to real-time versus static operating environments.
6) Remotely sensed imagery will become more widely used. More satellites equal more data. But other new satellites are now going to be providing information about CO2, NOx, global soil information and so on. Linking those satellite data to imagery will mean projects become larger, involve more people and take on the character of spatial data infrastructure (SDI).
7) I can’t help but think that we heading toward a major shift in energy use, production and utilisation. The way I see it, oil and gas together with wind, solar and biofuels etc. will require a balanced approach with feedback loops to operational building systems, social factors and other impacts. We’re about to enter a more holistically oriented and managed energy scenario. This goes back to integration - GIS.
8 ) Think communities. Better and more efficient housing located near better and more efficienct tranportation systems.
9) Learn to write. Develop communication skills. Many of our colleagues tell me, “I wish I could write.” It will help you to share and collaborate on all the integration going on.
10) Find a mentor. A person who would agree to work with you as your career develops and who you would invest a time commitment toward. It can be daunting when starting out and many people can help you to get up to speed quickly. If you want a mentor, then simply ask them. But know what you are asking and be prepared to listen.
All things change over time. This includes geographic information systems (GIS), computer aided design (CAD), global positioning systems (GPS), remote sensing, surveying and a wide array of geospatial technologies and applications. What I would have said to someone embarking on a spatially related career ten years ago would be different than what I would say today. Some things have changed dramatically, others in new ways and some minimally. Here is what I’d say today to someone contemplating a geo-career, in no particular order.
1) GNSS is an integration of GPS satellite systems. You can actually use a GNSS receiver today and get excellent results. If you thought one GPS was good, then 2 or 3 are going to really open your eyes. GNSS is going to revolutionise all we know about location based services. It will create a whole new class of professionals interested in position and navigation.
2) GIS is the de facto integrator of spatial information. Focus on it. Learn how all other technologies are spokes leading toward its integration. If you understand it as existing on a level equivalent to business systems then you will have the power to strategically drive new business applications and directions.
3) 3D is the future. It is not just about data though, it is also about visualisation. Start using the phrase ‘elegant solution.’ Pay attention to the concept of ‘Digital Cities.’
4) Sensing will increasing play a role that is supported through legislation. Data matters and numbers matter. Carbon credits become a currency, for example, and geotechnologies the stock exchange. I can’t say enough about understanding monitoring and it’s linkage to geospatial technologies. The current economic crisis will eventually lead to transparency and more of it.
5) Our concept of time is not well defined in spatial technologies. We can do scheduling well, but being able to understand ‘change over time’ is becoming more meaningful. It also relates closely to real-time versus static operating environments.
6) Remotely sensed imagery will become more widely used. More satellites equal more data. But other new satellites are now going to be providing information about CO2, NOx, global soil information and so on. Linking those satellite data to imagery will mean projects become larger, involve more people and take on the character of spatial data infrastructure (SDI).
7) I can’t help but think that we heading toward a major shift in energy use, production and utilisation. The way I see it, oil and gas together with wind, solar and biofuels etc. will require a balanced approach with feedback loops to operational building systems, social factors and other impacts. We’re about to enter a more holistically oriented and managed energy scenario. This goes back to integration - GIS.
8 ) Think communities. Better and more efficient housing located near better and more efficienct tranportation systems.
9) Learn to write. Develop communication skills. Many of our colleagues tell me, “I wish I could write.” It will help you to share and collaborate on all the integration going on.
10) Find a mentor. A person who would agree to work with you as your career develops and who you would invest a time commitment toward. It can be daunting when starting out and many people can help you to get up to speed quickly. If you want a mentor, then simply ask them. But know what you are asking and be prepared to listen.
25.05.2009
Animatie in chimie
Un site interesant cu diverse animatii pentru chimie. Se inscrie in tematica blogului. Comunicat de "ucenicul".
http://chimie.scola.ac-paris.fr/flash/electrolys.htm
http://chimie.scola.ac-paris.fr/sitedechimie/nouveautes.htm
http://chimie.scola.ac-paris.fr/flash/electrolys.htm
http://chimie.scola.ac-paris.fr/sitedechimie/nouveautes.htm
17.05.2009
Moda de-a lungul timpului
FASHION ERA
Fashion-era contains over 715 content rich, illustrated pages of Fashion History, Costume History, Clothing, Textile and Social History
16.05.2009
888 Flash Back Movies of Historical Events
Sunt filmulete de animatie pe teme istorice ; pot fi folosite ca ,, pretexte'' in inchegarea unor dialoguri incitante cu elevii .
http://www.flashones.com/events/070423_en.php
http://www.enotes.com/william-shakespeare/shakespeare-an-introduction
http://www.flashones.com/events/070423_en.php
http://www.enotes.com/william-shakespeare/shakespeare-an-introduction
Web Sites in the Virtual Grammar Lab
Pentru studiul limbii engleze
http://www.spunkyenglish.com/Century/listSites.php?Details=false&ListActivities=false
http://www.spunkyenglish.com/Century/listSites.php?Details=false&ListActivities=false
Istoria altfel
,,Cucerirea normanda a Angliei este reprezentata prin imagini pe „tapiseria de la Bayeux“, realizata in secolul al XI-lea, la curtea normanda a lui Wilhelm Cuceritorul si atribuită reginei Mathilde (1031 - 1083). Aceasta este o bucata de panza lunga de aproximativ 70 m si lata de circa 0,50 m pe care sunt brodate cu fire de lana in opt culori 58 de scene, incluzand peste cinci mii de personaje care au participat la evenimentele din 1066. Din Tapiserie rezulta ca au fost doborate paduri intregi pentru construirea si armarea a sapte sute cinzeci de corabii care trebuiau sa transporte, dupa calculele strategilor vremii, intre 12.000 si 15.000 de oameni peste Canal. Flota a fost gata la inceputul lunii septembrie 1066, dar inca cinsprezece zile, vanturi contrare l-au retinut pe Wilhelm in Normandia''(ALTERMEDIA.INFO)Cu HISTORIC TALE CONSTRUCTION KIT te distrezi imaginand povesti medievale !
15.05.2009
14.05.2009
13.05.2009
Bedford Gis Session
Check out this SlideShare Presentation:
Bedford Gis Session
View more presentations from GeoBlogs.
Resurse online pentru Limbi straine
1) Limba germana
http://www.learnalberta.ca/content/ilglt/Flash/index.html?launch=true
http://atschool.eduweb.co.uk/haberg/reallyusefulge/default.htm
http://www.bbc.co.uk/languages/german/dplus/index.shtml
http://web.wm.edu/modlang/gasmit/german/?svr=www
http://dspace.dial.pipex.com/town/square/fk26/xword.htm
http://gut.languageskills.co.uk/general/links.html
2) Limba franceza
http://www.prescot-school.knowsley.sch.uk/prescot-language/mfl-site/primarySchool/FrenchPrimary.htm
http://www.laits.utexas.edu/fi/
http://www.fusee.co.uk/
http://www.learnalberta.ca/content/flbla/index.html
http://www.learnalberta.ca/content/ilglt/Flash/index.html?launch=true
http://atschool.eduweb.co.uk/haberg/reallyusefulge/default.htm
http://www.bbc.co.uk/languages/german/dplus/index.shtml
http://web.wm.edu/modlang/gasmit/german/?svr=www
http://dspace.dial.pipex.com/town/square/fk26/xword.htm
http://gut.languageskills.co.uk/general/links.html
2) Limba franceza
http://www.prescot-school.knowsley.sch.uk/prescot-language/mfl-site/primarySchool/FrenchPrimary.htm
http://www.laits.utexas.edu/fi/
http://www.fusee.co.uk/
http://www.learnalberta.ca/content/flbla/index.html
Story Tools
A very nice collection of sites for slideshows, etc.
http://cogdogroo.wikispaces.com/StoryTools
http://cogdogroo.wikispaces.com/StoryTools
VCASMO
VCASMO is a multimedia presentation solution for personal photo-video slide show, business presentation, training, academic teaching, sales pitching, seminar, conference, press release meeting, live event.
http://www.vcasmo.com/
http://www.vcasmo.com/
12.05.2009
Meanders and Floodplains
Excellent animations to show how meanders and floodplains are formed. Suitable for use on an interactive whiteboard.
Discover how Rocks are Formed
The site explains in a simple way how igneous, sedimentary and metamorphic rocks are formed. There are also illustrated examples of each type of rock.
Virtual Rock Kit
Virtual Rock Kit
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