Attribut:Résumé DBP
De Remix Biens Communs
Cette propriété est de type Monolingual text.
V
Une ville — le milieu urbain — est à la fois un milieu physique et humain où se concentre une population qui organise son espace en fonction du site et de son environnement, en fonction de ses besoins et de ses activités propres et aussi de contingences notamment socio-politiques. La ville est un milieu complexe qui ne peut cependant pas se résumer à une approche physique, car l'espace urbain est aussi la traduction spatiale de l'organisation dans l'espace et dans le temps des hommes et de leurs activités dans un contexte donné. Ce contexte est autant physique, économique, politique, social ou culturel. L'approche de la ville ne peut être que diachronique et l'histoire des villes, de chaque ville ou agglomération reste un élément d'analyse essentiel. La ville peut être comparée avec un écosystème qui interagit en permanence comme un milieu avec ses hôtes. Les principes qui régissent la structure et l'organisation de la ville sont étudiés par la sociologie urbaine, l'urbanisme ou encore l'économie urbaine. (fr) +, A city is a large human settlement. It can be defined as a permanent and densely settled place with administratively defined boundaries whose members work primarily on non-agricultural tasks. Cities generally have extensive systems for housing, transportation, sanitation, utilities, land use, production of goods, and communication. Their density facilitates interaction between people, government organisations and businesses, sometimes benefiting different parties in the process, such as improving efficiency of goods and service distribution. Historically, city-dwellers have been a small proportion of humanity overall, but following two centuries of unprecedented and rapid urbanization, more than half of the world population now lives in cities, which has had profound consequences for global sustainability. Present-day cities usually form the core of larger metropolitan areas and urban areas—creating numerous commuters traveling towards city centres for employment, entertainment, and education. However, in a world of intensifying globalization, all cities are to varying degrees also connected globally beyond these regions. This increased influence means that cities also have significant influences on global issues, such as sustainable development, global warming, and global health. Because of these major influences on global issues, the international community has prioritized investment in sustainable cities through Sustainable Development Goal 11. Due to the efficiency of transportation and the smaller land consumption, dense cities hold the potential to have a smaller ecological footprint per inhabitant than more sparsely populated areas. Therefore, compact cities are often referred to as a crucial element of fighting climate change. However, this concentration can also have significant negative consequences, such as forming urban heat islands, concentrating pollution, and stressing water supplies and other resources. Other important traits of cities besides population include the capital status and relative continued occupation of the city. For example, country capitals such as Beijing, London, Mexico City, Moscow, Nairobi, New Delhi, Paris, Rome, Athens, Seoul, Singapore, Tokyo, Manila, and Washington, D.C. reflect the identity and apex of their respective nations. Some historic capitals, such as Kyoto and Xi'an, maintain their reflection of cultural identity even without modern capital status. Religious holy sites offer another example of capital status within a religion, Jerusalem, Mecca, Varanasi, Ayodhya, Haridwar and Prayagraj each hold significance. (en)
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The Semantic Web, sometimes known as Web 3.0 (not to be confused with Web3), is an extension of the World Wide Web through standards set by the World Wide Web Consortium (W3C). The goal of the Semantic Web is to make Internet data machine-readable. To enable the encoding of semantics with the data, technologies such as Resource Description Framework (RDF) and Web Ontology Language (OWL) are used. These technologies are used to formally represent metadata. For example, ontology can describe concepts, relationships between entities, and categories of things. These embedded semantics offer significant advantages such as reasoning over data and operating with heterogeneous data sources. These standards promote common data formats and exchange protocols on the Web, fundamentally the RDF. According to the W3C, "The Semantic Web provides a common framework that allows data to be shared and reused across application, enterprise, and community boundaries." The Semantic Web is therefore regarded as an integrator across different content and information applications and systems. The term was coined by Tim Berners-Lee for a web of data (or data web) that can be processed by machines—that is, one in which much of the meaning is machine-readable. While its critics have questioned its feasibility, proponents argue that applications in library and information science, industry, biology and human sciences research have already proven the validity of the original concept. Berners-Lee originally expressed his vision of the Semantic Web in 1999 as follows: I have a dream for the Web [in which computers] become capable of analyzing all the data on the Web – the content, links, and transactions between people and computers. A "Semantic Web", which makes this possible, has yet to emerge, but when it does, the day-to-day mechanisms of trade, bureaucracy and our daily lives will be handled by machines talking to machines. The "intelligent agents" people have touted for ages will finally materialize. The 2001 Scientific American article by Berners-Lee, Hendler, and Lassila described an expected evolution of the existing Web to a Semantic Web. In 2006, Berners-Lee and colleagues stated that: "This simple idea…remains largely unrealized".In 2013, more than four million Web domains (out of roughly 250 million total) contained Semantic Web markup. (en)
La Terre est la troisième planète par ordre d'éloignement au Soleil et la cinquième plus grande du Système solaire aussi bien par la masse que le diamètre. Par ailleurs, elle est le seul objet céleste connu pour abriter la vie. Elle orbite autour du Soleil en 365,256 jours solaires — une année sidérale — et réalise une rotation sur elle-même relativement au Soleil en 23 h 56 min 4 s — un jour sidéral — soit un peu moins que son jour solaire de 24 h du fait de ce déplacement autour du Soleil. L'axe de rotation de la Terre possède une inclinaison de 23°, ce qui cause l'apparition des saisons. D'après la datation radiométrique, la Terre s'est formée il y a 4,54 milliards d'années. Elle possède un unique satellite naturel, la Lune, qui s'est formée peu après. L'interaction gravitationnelle avec son satellite crée les marées, stabilise son axe de rotation et réduit graduellement sa vitesse de rotation. La vie serait apparue dans les océans il y a au moins 3,5 milliards d'années, ce qui a affecté l'atmosphère et la surface terrestre par la prolifération d'organismes d'abord anaérobies puis, à la suite de l'explosion cambrienne, aérobies. Une combinaison de facteurs tels que la distance de la Terre au Soleil (environ 150 millions de kilomètres — une unité astronomique —), son atmosphère, sa couche d'ozone, son champ magnétique et son évolution géologique ont permis à la vie d'évoluer et de se développer. Durant l'histoire évolutive du vivant, la biodiversité a connu de longues périodes d'expansion occasionnellement ponctuées par des extinctions massives ; environ 99 % des espèces qui ont un jour vécu sur Terre sont maintenant éteintes. En 2020, plus de 7,7 milliards d'êtres humains vivent sur Terre et dépendent de sa biosphère et de ses ressources naturelles pour leur survie. La Terre est la planète la plus dense du Système solaire ainsi que la plus grande et massive des quatre planètes telluriques. Son enveloppe rigide — appelée la lithosphère — est divisée en différentes plaques tectoniques qui migrent de quelques centimètres par an. Environ 71 % de la surface de la planète est couverte d'eau — notamment des océans, mais aussi des lacs et rivières, constituant l'hydrosphère — et les 29 % restants sont des continents et des îles. La majeure partie des régions polaires est couverte de glace, notamment avec l'inlandsis de l'Antarctique et la banquise de l'océan Arctique. La structure interne de la Terre est géologiquement active, le noyau interne solide et le noyau externe liquide (composés tous deux essentiellement de fer) permettant notamment de générer le champ magnétique terrestre par effet dynamo et la convection du manteau terrestre (composé de roches silicatées) étant la cause de la tectonique des plaques. (fr) , Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surface is made up of the ocean, dwarfing Earth's polar ice, lakes, and rivers. The remaining 29% of Earth's surface is land, consisting of continents and islands. Earth's surface layer is formed of several slowly moving tectonic plates, interacting to produce mountain ranges, volcanoes, and earthquakes. Earth's liquid outer core generates the magnetic field that shapes Earth's magnetosphere, deflecting destructive solar winds. Earth's atmosphere consists mostly of nitrogen and oxygen. More solar energy is received by tropical regions than polar regions and is redistributed by atmospheric and ocean circulation. Water vapor is widely present in the atmosphere and forms clouds that cover most of the planet. Greenhouse gases in the atmosphere like carbon dioxide (CO2) trap a part of the energy from the Sun close to the surface. A region's climate is governed by latitude, but also by elevation and proximity to moderating oceans. Severe weather, such as tropical cyclones, thunderstorms, and heatwaves, occurs in most areas and greatly impacts life. Earth is an ellipsoid with a circumference of about 40,000 km. It is the densest planet in the Solar System. Of the four rocky planets, it is the largest and most massive. Earth is about eight light minutes away from the Sun and orbits it, taking a year (about 365.25 days) to complete one revolution. Earth rotates around its own axis in slightly less than a day (in about 23 hours and 56 minutes). is tilted with respect to the perpendicular to its orbital plane around the Sun, producing seasons. Earth is orbited by one permanent natural satellite, the Moon, which orbits Earth at 380,000 km (1.3 light seconds) and is roughly a quarter as wide as Earth. The Moon always faces the Earth with the same side through tidal locking and causes tides, stabilizes Earth's axis, and gradually slows its rotation. Earth formed over 4.5 billion years ago. During the first billion years of Earth's history, the ocean formed and then life developed within it. Life spread globally and began to affect Earth's atmosphere and surface, leading to Earth's Great Oxidation Event two billion years ago. Humans emerged 300,000 years ago, and have reached a population of almost 8 billion today. Humans depend on Earth's biosphere and natural resources for their survival, but have increasingly impacted Earth's environment. Today, humanity's impact on Earth's climate, soils, waters, and ecosystems is unsustainable, threatening people's lives and causing widespread extinction of other life. (en) , La Tierra (del latín Terra, deidad romana equivalente a Gea, diosa griega de la feminidad y la fecundidad) es un planeta del sistema solar que gira alrededor de su estrella —el Sol— en la tercera órbita más interna. Es el más denso y el quinto mayor de los ocho planetas del sistema solar. También es el mayor de los cuatro terrestres o rocosos. La Tierra se formó hace aproximadamente 4550 millones de años y la vida surgió unos mil millones de años después. Es el hogar de millones de especies, incluidos los seres humanos y actualmente el único cuerpo astronómico donde se conoce la existencia de vida. La atmósfera y otras condiciones abióticas han sido alteradas significativamente por la biosfera del planeta, favoreciendo la proliferación de organismos aerobios, así como la formación de una capa de ozono que junto con el campo magnético terrestre bloquean la radiación solar dañina, permitiendo así la vida en la Tierra. Las propiedades físicas de la Tierra, la historia geológica y su órbita han permitido que la vida siga existiendo. Se estima que el planeta seguirá siendo capaz de sustentar vida durante otros 500 millones de años, ya que según las previsiones actuales, pasado ese tiempo la creciente luminosidad del Sol terminará causando la extinción de la biosfera. La superficie terrestre o corteza está dividida en varias placas tectónicas que se deslizan sobre el magma durante periodos de varios millones de años. La superficie está cubierta por continentes e islas; estos poseen varios lagos, ríos y otras fuentes de agua, que junto con los océanos de agua salada que representan cerca del 71 % de la superficie constituyen la hidrósfera. No se conoce ningún otro planeta con este equilibrio de agua líquida, que es indispensable para cualquier tipo de vida conocida. Los polos de la Tierra están cubiertos en su mayoría de hielo sólido (indlandsis de la Antártida) o de banquisas (casquete polar ártico). El interior del planeta es geológicamente activo, con una gruesa capa de manto relativamente sólido, un núcleo externo líquido que genera un campo magnético, y un sólido núcleo interior compuesto por aproximadamente un 88 % de hierro. La Tierra interactúa gravitatoriamente con otros objetos en el espacio, especialmente el Sol y la Luna. En la actualidad, la Tierra completa una órbita alrededor del Sol cada vez que realiza 366,26 giros sobre su eje, lo cual es equivalente a 365,26 días solares o un año sideral. El eje de rotación de la Tierra se encuentra inclinado 23,4° con respecto a la perpendicular a su plano orbital, lo que produce las variaciones estacionales en la superficie del planeta con un período de un año tropical (365,24 días solares). La Tierra posee un único satélite natural, la Luna, que comenzó a orbitar la Tierra hace 4530 millones de años; esta produce las mareas, estabiliza la inclinación del eje terrestre y reduce gradualmente la velocidad de rotación del planeta. Hace aproximadamente 3800 a 4100 millones de años, durante el llamado bombardeo intenso tardío, numerosos asteroides impactaron en la Tierra, causando significativos cambios en la mayor parte de su superficie. Tanto los minerales del planeta como los productos de la biosfera aportan recursos que se utilizan para sostener a la población humana mundial. Sus habitantes están agrupados en unos 200 estados soberanos independientes, que interactúan a través de la diplomacia, los viajes, el comercio y la acción militar. Las culturas humanas han desarrollado muchas ideas sobre el planeta, incluida la personificación de una deidad, la creencia en una Tierra plana o en la Tierra como centro del universo, y una perspectiva moderna del mundo como un entorno integrado que requiere administración. (es) , …
Z
Zapatismo is the armed movement identified with the ideas of Emiliano Zapata, leader of the Mexican Revolution, reflected mainly in the Plan of Ayala term 1911. The members of the Liberation Army of the South led by Zapata were known as "Zapatistas". One of the most symbolic phrases of Zapatismo was that the land belongs to the tiller, reflecting a kind of agrarian socialism, originally coined by Zapata himself while trying to remove the chieftaincy in Mexico and restore possession of the land to the peasant classes in the south. The phrase and what it represents became the symbols of Mexican agrarianism. (en) +
