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101-528: A further definition is given in Kuhn (2005): "An SDI is a coordinated series of agreements on technology standards, institutional arrangements, and policies that enable the discovery and use of geospatial information by users and for purposes other than those it was created for." Some of the main principles are that data and metadata should not be managed centrally, but by the data originator and/or owner, and that tools and services connect via computer networks to

202-409: A monolithic design . SOA is a good choice for system integration . By consequence, it is also applied in the field of software design where services are provided to the other components by application components , through a communication protocol over a network. A service is a discrete unit of functionality that can be accessed remotely and acted upon and updated independently, such as retrieving

303-427: A relational database to categorize cultural works and their images. Relational databases and metadata work to document and describe the complex relationships amongst cultural objects and multi-faceted works of art, as well as between objects and places, people, and artistic movements. Relational database structures are also beneficial within collecting institutions and museums because they allow for archivists to make

404-454: A "data element" registry, its purpose is to support describing and registering metadata content independently of any particular application, lending the descriptions to being discovered and reused by humans or computers in developing new applications, databases, or for analysis of data collected in accordance with the registered metadata content. This standard has become the general basis for other kinds of metadata registries, reusing and extending

505-472: A business part, a functional part and a technical part. Service composition patterns have two broad, high-level architectural styles: choreography and orchestration . Lower level enterprise integration patterns that are not bound to a particular architectural style continue to be relevant and eligible in SOA design. Service-oriented architecture can be implemented with web services or Microservices . This

606-772: A class-attribute-value triple. The first 2 elements of the triple (class, attribute) are pieces of some structural metadata having a defined semantic. The third element is a value, preferably from some controlled vocabulary, some reference (master) data. The combination of the metadata and master data elements results in a statement which is a metacontent statement i.e. "metacontent = metadata + master data". All of these elements can be thought of as "vocabulary". Both metadata and master data are vocabularies that can be assembled into metacontent statements. There are many sources of these vocabularies, both meta and master data: UML, EDIFACT, XSD, Dewey/UDC/LoC, SKOS, ISO-25964, Pantone, Linnaean Binomial Nomenclature, etc. Using controlled vocabularies for

707-417: A clear distinction between cultural objects and their images; an unclear distinction could lead to confusing and inaccurate searches. An object's materiality, function, and purpose, as well as the size (e.g., measurements, such as height, width, weight), storage requirements (e.g., climate-controlled environment), and focus of the museum and collection, influence the descriptive depth of the data attributed to

808-480: A computer program intended to simplify the implementation and maintenance of software. An API can be thought of as the service, and the SOA the architecture that allows the service to operate. Note that Service-Oriented Architecture must not be confused with Service Based Architecture as those are two different architectural styles. In SOA, services use protocols that describe how they pass and parse messages using description metadata . This metadata describes both

909-413: A credit card statement online. SOA is also intended to be independent of vendors, products and technologies. Service orientation is a way of thinking in terms of services and service-based development and the outcomes of services. A service has four properties according to one of many definitions of SOA: Different services can be used in conjunction as a service mesh to provide the functionality of

1010-619: A file. SOA has been conflated with Web services ; however, Web services are only one option to implement the patterns that comprise the SOA style. In the absence of native or binary forms of remote procedure call (RPC), applications could run more slowly and require more processing power, increasing costs. Most implementations do incur these overheads, but SOA can be implemented using technologies (for example, Java Business Integration (JBI), Windows Communication Foundation (WCF) and data distribution service (DDS)) that do not depend on remote procedure calls or translation through XML or JSON. At

1111-485: A key topic in efforts toward international standardization . Standards for metadata in digital libraries include Dublin Core , METS , MODS , DDI , DOI , URN , PREMIS schema, EML , and OAI-PMH . Leading libraries in the world give hints on their metadata standards strategies. The use and creation of metadata in library and information science also include scientific publications: Metadata for scientific publications

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1212-486: A large software application , a principle SOA shares with modular programming . Service-oriented architecture integrates distributed, separately maintained and deployed software components. It is enabled by technologies and standards that facilitate components' communication and cooperation over a network, especially over an IP network. SOA is related to the idea of an API ( application programming interface ), an interface or communication protocol between different parts of

1313-408: A library might hold in its collection. Until the 1980s, many library catalogs used 3x5 inch cards in file drawers to display a book's title, author, subject matter, and an abbreviated alpha-numeric string ( call number ) which indicated the physical location of the book within the library's shelves. The Dewey Decimal System employed by libraries for the classification of library materials by subject

1414-514: A network in order to allow users to combine and reuse them in the production of applications. These services and their corresponding consumers communicate with each other by passing data in a well-defined, shared format, or by coordinating an activity between two or more services. SOA can be seen as part of the continuum which ranges from the older concept of distributed computing and modular programming , through SOA, and on to practices of mashups , SaaS , and cloud computing (which some see as

1515-511: A problem with alternative approaches: Here's a new language we want you to learn, and now you need to output these additional files on your server. It's a hassle. (Microformats) lower the barrier to entry. Most common types of computer files can embed metadata, including documents, (e.g. Microsoft Office files, OpenDocument files, PDF ) images, (e.g. JPEG , PNG ) Video files, (e.g. AVI , MP4 ) and audio files. (e.g. WAV , MP3 ) Metadata may be added to files by users, but some metadata

1616-427: A resource. Statistical data repositories have their own requirements for metadata in order to describe not only the source and quality of the data but also what statistical processes were used to create the data, which is of particular importance to the statistical community in order to both validate and improve the process of statistical data production. An additional type of metadata beginning to be more developed

1717-632: A revolution. It captures many of the best practices of previous software architectures. In communications systems, for example, little development of solutions that use truly static bindings to talk to other equipment in the network has taken place. By embracing a SOA approach, such systems can position themselves to stress the importance of well-defined, highly inter-operable interfaces. Other predecessors of SOA include Component-based software engineering and Object-Oriented Analysis and Design (OOAD) of remote objects, for instance, in CORBA . A service comprises

1818-512: A stand-alone unit of functionality available only via a formally defined interface. Services can be some kind of "nano-enterprises" that are easy to produce and improve. Also services can be "mega-corporations" constructed as the coordinated work of subordinate services. Reasons for treating the implementation of services as separate projects from larger projects include: SOA promises to simplify testing indirectly. Services are autonomous, stateless, with fully documented interfaces, and separate from

1919-421: A wide range of technologies, including: Implementations can use one or more of these protocols and, for example, might use a file-system mechanism to communicate data following a defined interface specification between processes conforming to the SOA concept. The key is independent services with defined interfaces that can be called to perform their tasks in a standard way, without a service having foreknowledge of

2020-461: A year, regardless of whether or not they [ever] were persons of interest to the agency. Geospatial metadata relates to Geographic Information Systems (GIS) files, maps, images, and other data that is location-based. Metadata is used in GIS to document the characteristics and attributes of geographic data, such as database files and data that is developed within a GIS. It includes details like who developed

2121-676: Is accessibility metadata . Accessibility metadata is not a new concept to libraries; however, advances in universal design have raised its profile. Projects like Cloud4All and GPII identified the lack of common terminologies and models to describe the needs and preferences of users and information that fits those needs as a major gap in providing universal access solutions. Those types of information are accessibility metadata. Schema.org has incorporated several accessibility properties based on IMS Global Access for All Information Model Data Element Specification. The Wiki page WebSchemas/Accessibility lists several properties and their values. While

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2222-842: Is " data that provides information about other data", but not the content of the data itself, such as the text of a message or the image itself. There are many distinct types of metadata, including: Metadata is not strictly bound to one of these categories, as it can describe a piece of data in many other ways. Metadata has various purposes. It can help users find relevant information and discover resources . It can also help organize electronic resources, provide digital identification, and archive and preserve resources. Metadata allows users to access resources by "allowing resources to be found by relevant criteria, identifying resources, bringing similar resources together, distinguishing dissimilar resources, and giving location information". Metadata of telecommunication activities including Internet traffic

2323-500: Is a European Commission initiative to build a European SDI beyond national boundaries; the United Nations Spatial Data Infrastructure ( UNSDI ) plans to do the same for over 30 UN Funds, Programs, Specialized Agencies and member countries. An SDI should enable the discovery and delivery of spatial data from a data repository, via a spatial service provider, to a user. As mentioned earlier it

2424-423: Is an SOA framework that identifies the various disciplines that guide SOA practitioners to conceptualize, analyze, design, and architect their service-oriented assets. The Service-oriented modeling framework (SOMF) offers a modeling language and a work structure or "map" depicting the various components that contribute to a successful service-oriented modeling approach. It illustrates the major elements that identify

2525-438: Is an early example of metadata usage. The early paper catalog had information regarding whichever item was described on said card: title, author, subject, and a number as to where to find said item. Beginning in the 1980s and 1990s, many libraries replaced these paper file cards with computer databases. These computer databases make it much easier and faster for users to do keyword searches. Another form of older metadata collection

2626-491: Is being accomplished in the national and international standards communities, especially ANSI (American National Standards Institute) and ISO (International Organization for Standardization) to reach a consensus on standardizing metadata and registries. The core metadata registry standard is ISO / IEC 11179 Metadata Registries (MDR), the framework for the standard is described in ISO/IEC 11179-1:2004. A new edition of Part 1

2727-486: Is clear that he uses the term in the ISO 11179 "traditional" sense, which is "structural metadata" i.e. "data about the containers of data"; rather than the alternative sense "content about individual instances of data content" or metacontent, the type of data usually found in library catalogs. Since then the fields of information management, information science, information technology, librarianship, and GIS have widely adopted

2828-470: Is completely discrete from other elements and classified according to one dimension only. An example of a linear metadata schema is the Dublin Core schema, which is one-dimensional. Metadata schemata are often 2 dimensional, or planar, where each element is completely discrete from other elements but classified according to 2 orthogonal dimensions. The degree to which the data or metadata is structured

2929-420: Is done to make the functional building-blocks accessible over standard Internet protocols that are independent of platforms and programming languages. These services can represent either new applications or just wrappers around existing legacy systems to make them network-enabled. Implementers commonly build SOAs using web services standards. One example is SOAP , which has gained broad industry acceptance after

3030-560: Is in its final stage for publication in 2015 or early 2016. It has been revised to align with the current edition of Part 3, ISO/IEC 11179-3:2013 which extends the MDR to support the registration of Concept Systems. (see ISO/IEC 11179 ). This standard specifies a schema for recording both the meaning and technical structure of the data for unambiguous usage by humans and computers. ISO/IEC 11179 standard refers to metadata as information objects about data, or "data about data". In ISO/IEC 11179 Part-3,

3131-400: Is managing of metadata. Environments based on SOA include many services which communicate among each other to perform tasks. Due to the fact that the design may involve multiple services working in conjunction, an Application may generate millions of messages. Further services may belong to different organizations or even competing firms creating a huge trust issue. Thus SOA governance comes into

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3232-454: Is more work to be done. Metadata (metacontent) or, more correctly, the vocabularies used to assemble metadata (metacontent) statements, is typically structured according to a standardized concept using a well-defined metadata scheme, including metadata standards and metadata models . Tools such as controlled vocabularies , taxonomies , thesauri , data dictionaries , and metadata registries can be used to apply further standardization to

3333-608: Is most commonly used in museum contexts for object identification and resource recovery purposes. Metadata is developed and applied within collecting institutions and museums in order to: Many museums and cultural heritage centers recognize that given the diversity of artworks and cultural objects, no single model or standard suffices to describe and catalog cultural works. For example, a sculpted Indigenous artifact could be classified as an artwork, an archaeological artifact, or an Indigenous heritage item. The early stages of standardization in archiving, description and cataloging within

3434-533: Is no intelligence or "inferencing" occurring, just the illusion thereof. Metadata schemata can be hierarchical in nature where relationships exist between metadata elements and elements are nested so that parent-child relationships exist between the elements. An example of a hierarchical metadata schema is the IEEE LOM schema, in which metadata elements may belong to a parent metadata element. Metadata schemata can also be one-dimensional, or linear, where each element

3535-555: Is no single commonly agreed definition of microservices. The following characteristics and principles can be found in the literature: Interactive applications requiring real-time response times, for example low-latency interactive 3d applications, are using specific service oriented architectures addressing the specific needs of such kind of applications. These include for example low-latency optimized distributed computation and communication as well as resource and instance management. Metadata Metadata (or metainformation )

3636-636: Is not only on creation and capture, but moreover on maintenance costs. As soon as the metadata structures become outdated, so too is the access to the referred data. Hence granularity must take into account the effort to create the metadata as well as the effort to maintain it. In all cases where the metadata schemata exceed the planar depiction, some type of hypermapping is required to enable display and view of metadata according to chosen aspect and to serve special views. Hypermapping frequently applies to layering of geographical and geological information overlays. International standards apply to metadata. Much work

3737-494: Is often automatically added to files by authoring applications or by devices used to produce the files, without user intervention. While metadata in files are useful for finding them, they can be a privacy hazard when the files are shared. Using metadata removal tools to clean files before sharing them can mitigate this risk. Metadata may be written into a digital photo file that will identify who owns it, copyright and contact information, what brand or model of camera created

3838-403: Is often created by journal publishers and citation databases such as PubMed and Web of Science . The data contained within manuscripts or accompanying them as supplementary material is less often subject to metadata creation, though they may be submitted to e.g. biomedical databases after publication. The original authors and database curators then become responsible for metadata creation, with

3939-534: Is often wished that the data provider is able to update spatial data stored in a repository. Hence, the basic software components of an SDI are: Besides these software components, a range of (international) technical standards are necessary that allow interaction between the different software components. Among those are geospatial standards defined by the Open Geospatial Consortium (e.g., OGC WMS, WFS, GML, etc.) and ISO (e.g., ISO 19115) for

4040-412: Is referred to as "granularity" . "Granularity" refers to how much detail is provided. Metadata with a high granularity allows for deeper, more detailed, and more structured information and enables a greater level of technical manipulation. A lower level of granularity means that metadata can be created for considerably lower costs but will not provide as detailed information. The major impact of granularity

4141-774: Is saved as persistent repository and describe business objects in various enterprise systems and applications. Structural metadata commonality is also important to support data virtualization. Standardization and harmonization work has brought advantages to industry efforts to build metadata systems in the statistical community. Several metadata guidelines and standards such as the European Statistics Code of Practice and ISO 17369:2013 ( Statistical Data and Metadata Exchange or SDMX) provide key principles for how businesses, government bodies, and other entities should manage statistical data and metadata. Entities such as Eurostat , European System of Central Banks , and

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4242-558: Is set within the business. They can also develop enterprise-wide SOA that encapsulates a business-oriented infrastructure. SOA has also been illustrated as a highway system providing efficiency for car drivers. The point being that if everyone had a car, but there was no highway anywhere, things would be limited and disorganized, in any attempt to get anywhere quickly or efficiently. IBM Vice President of Web Services Michael Liebow says that SOA "builds highways". In some respects, SOA could be regarded as an architectural evolution rather than as

4343-523: Is stored in the integrated library management system, ILMS , using the MARC metadata standard. The purpose is to direct patrons to the physical or electronic location of items or areas they seek as well as to provide a description of the item/s in question. More recent and specialized instances of library metadata include the establishment of digital libraries including e-print repositories and digital image libraries. While often based on library principles,

4444-485: Is the bibliographic classification, the subject, the Dewey Decimal class number . There is always an implied statement in any "classification" of some object. To classify an object as, for example, Dewey class number 514 (Topology) (i.e. books having the number 514 on their spine) the implied statement is: "<book><subject heading><514>". This is a subject-predicate-object triple, or more importantly,

4545-484: Is the use by the US Census Bureau of what is known as the "Long Form". The Long Form asks questions that are used to create demographic data to find patterns of distribution. Libraries employ metadata in library catalogues , most commonly as part of an Integrated Library Management System . Metadata is obtained by cataloging resources such as books, periodicals, DVDs, web pages or digital images. This data

4646-567: Is usually expressed as a set of keywords in a natural language. According to Ralph Kimball , metadata can be divided into three categories: technical metadata (or internal metadata), business metadata (or external metadata), and process metadata . NISO distinguishes three types of metadata: descriptive, structural, and administrative. Descriptive metadata is typically used for discovery and identification, as information to search and locate an object, such as title, authors, subjects, keywords, and publisher. Structural metadata describes how

4747-420: Is very widely collected by various national governmental organizations. This data is used for the purposes of traffic analysis and can be used for mass surveillance . Metadata was traditionally used in the card catalogs of libraries until the 1980s when libraries converted their catalog data to digital databases . In the 2000s, as data and information were increasingly stored digitally, this digital data

4848-420: The U.S. Environmental Protection Agency have implemented these and other such standards and guidelines with the goal of improving "efficiency when managing statistical business processes". Metadata has been used in various ways as a means of cataloging items in libraries in both digital and analog formats. Such data helps classify, aggregate, identify, and locate a particular book, DVD, magazine, or any object

4949-419: The contents and context of data or data files increases its usefulness. For example, a web page may include metadata specifying what software language the page is written in (e.g., HTML), what tools were used to create it, what subjects the page is about, and where to find more information about the subject. This metadata can automatically improve the reader's experience and make it easier for users to find

5050-445: The network in order to fulfill a goal. These services use technology agnostic protocols , which aid in encapsulating choice of language and frameworks, making their choice a concern internal to the service. Microservices are a new realisation and implementation approach to SOA, which have become popular since 2014 (and after the introduction of DevOps ), and which also emphasize continuous deployment and other agile practices. There

5151-479: The "what to do" aspects of a service development scheme. The model enables practitioners to craft a project plan and to identify the milestones of a service-oriented initiative. SOMF also provides a common modeling notation to address alignment between business and IT organizations. Some enterprise architects believe that SOA can help businesses respond more quickly and more cost-effectively to changing market conditions. This style of architecture promotes reuse at

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5252-499: The CCO, are integrated within a Museum's Collections Management System (CMS), a database through which museums are able to manage their collections, acquisitions, loans and conservation. Scholars and professionals in the field note that the "quickly evolving landscape of standards and technologies" creates challenges for cultural documentarians, specifically non-technically trained professionals. Most collecting institutions and museums use

5353-563: The Library of Congress Controlled Vocabularies are reputable within the museum community and are recommended by CCO standards. Museums are encouraged to use controlled vocabularies that are contextual and relevant to their collections and enhance the functionality of their digital information systems. Controlled Vocabularies are beneficial within databases because they provide a high level of consistency, improving resource retrieval. Metadata structures, including controlled vocabularies, reflect

5454-812: The assistance of automated processes. Comprehensive metadata for all experimental data is the foundation of the FAIR Guiding Principles , or the standards for ensuring research data are findable , accessible , interoperable , and reusable . Such metadata can then be utilized, complemented, and made accessible in useful ways. OpenAlex is a free online index of over 200 million scientific documents that integrates and provides metadata such as sources, citations , author information , scientific fields , and research topics. Its API and open source website can be used for metascience, scientometrics , and novel tools that query this semantic web of papers . Another project under development, Scholia , uses

5555-563: The author is, when the document was written, and a short summary of the document. Metadata within web pages can also contain descriptions of page content, as well as key words linked to the content. These links are often called "Metatags", which were used as the primary factor in determining order for a web search until the late 1990s. The reliance on metatags in web searches was decreased in the late 1990s because of "keyword stuffing", whereby metatags were being largely misused to trick search engines into thinking some websites had more relevance in

5656-437: The calling application, and without the application having or needing knowledge of how the service actually performs its tasks. SOA enables the development of applications that are built by combining loosely coupled and interoperable services. These services inter-operate based on a formal definition (or contract, e.g., WSDL) that is independent of the underlying platform and programming language. The interface definition hides

5757-574: The components of an object are organized. An example of structural metadata would be how pages are ordered to form chapters of a book. Finally, administrative metadata gives information to help manage the source. Administrative metadata refers to the technical information, such as file type, or when and how the file was created. Two sub-types of administrative metadata are rights management metadata and preservation metadata. Rights management metadata explains intellectual property rights , while preservation metadata contains information to preserve and save

5858-428: The components of metacontent statements, whether for indexing or finding, is endorsed by ISO 25964 : "If both the indexer and the searcher are guided to choose the same term for the same concept, then relevant documents will be retrieved." This is particularly relevant when considering search engines of the internet, such as Google. The process indexes pages and then matches text strings using its complex algorithm; there

5959-501: The concept of loosely coupling services has inspired researchers to elaborate on similarities between the two philosophies, SOA and Web 2.0, and their respective applications. Some argue Web 2.0 and SOA have significantly different elements and thus can not be regarded "parallel philosophies", whereas others consider the two concepts as complementary and regard Web 2.0 as the global SOA. The philosophies of Web 2.0 and SOA serve different user needs and thus expose differences with respect to

6060-741: The content is desirable. This is particularly useful in video applications such as Automatic Number Plate Recognition and Vehicle Recognition Identification software, wherein license plate data is saved and used to create reports and alerts. There are 2 sources in which video metadata is derived: (1) operational gathered metadata, that is information about the content produced, such as the type of equipment, software, date, and location; (2) human-authored metadata, to improve search engine visibility, discoverability, audience engagement, and providing advertising opportunities to video publishers. Avid's MetaSync and Adobe's Bridge are examples of professional video editing software with access to metadata. Information on

6161-448: The cross-cutting concerns of the implementation. If an organization possesses appropriately defined test data, then a corresponding stub is built that reacts to the test data when a service is being built. A full set of regression tests, scripts, data, and responses is also captured for the service. The service can be tested as a 'black box' using existing stubs corresponding to the services it calls. Test environments can be constructed where

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6262-464: The data, when it was collected, how it was processed, and what formats it's available in, and then delivers the context for the data to be used effectively. Metadata can be created either by automated information processing or by manual work. Elementary metadata captured by computers can include information about when an object was created, who created it, when it was last updated, file size, and file extension. In this context an object refers to any of

6363-413: The data; it is used to summarize basic information about data that can make tracking and working with specific data easier. Some examples include: For example, a digital image may include metadata that describes the size of the image, its color depth, resolution, when it was created, the shutter speed, and other data. A text document's metadata may contain information about how long the document is, who

6464-442: The delivery of maps, vector and raster data , but also data format and internet transfer standards by W3C consortium. List by country or administrative zone. It is not complete, is a sample of National Spatial Data Infrastructure (NSDI) official websites. Service oriented architecture In software engineering , service-oriented architecture ( SOA ) is an architectural style that focuses on discrete services instead of

6565-414: The design and also the technologies used in real-world applications. However, as of 2008 , use-cases demonstrated the potential of combining technologies and principles of both Web 2.0 and SOA. Microservices are a modern interpretation of service-oriented architectures used to build distributed software systems . Services in a microservice architecture are processes that communicate with each other over

6666-457: The drawback that it could reduce the overall scalability of the service provider if the service-provider needs to retain the shared context for each consumer. It also increases the coupling between a service provider and a consumer and makes switching service providers more difficult. Ultimately, some critics feel that SOA services are still too constrained by applications they represent. A primary challenge faced by service-oriented architecture

6767-467: The efforts to describe and standardize the varied accessibility needs of information seekers are beginning to become more robust, their adoption into established metadata schemas has not been as developed. For example, while Dublin Core (DC)'s "audience" and MARC 21's "reading level" could be used to identify resources suitable for users with dyslexia and DC's "format" could be used to identify resources available in braille, audio, or large print formats, there

6868-532: The environment. Managing the data state of idempotent services is the only complexity. Examples may prove useful to aid in documenting a service to the level where it becomes useful. The documentation of some APIs within the Java Community Process provide good examples. As these are exhaustive, staff would typically use only important subsets. The 'ossjsa.pdf' file within JSR-89 exemplifies such

6969-506: The file, along with exposure information (shutter speed, f-stop, etc.) and descriptive information, such as keywords about the photo, making the file or image searchable on a computer and/or the Internet. Some metadata is created by the camera such as, color space, color channels, exposure time, and aperture (EXIF), while some is input by the photographer and/or software after downloading to a computer. Most digital cameras write metadata about

7070-446: The focus on non-librarian use, especially in providing metadata, means they do not follow traditional or common cataloging approaches. Given the custom nature of included materials, metadata fields are often specially created e.g. taxonomic classification fields, location fields, keywords, or copyright statement. Standard file information such as file size and format are usually automatically included. Library operation has for decades been

7171-425: The following: A metadata engine collects, stores and analyzes information about data and metadata in use within a domain. Data virtualization emerged in the 2000s as the new software technology to complete the virtualization "stack" in the enterprise. Metadata is used in data virtualization servers which are enterprise infrastructure components, alongside database and application servers. Metadata in these servers

7272-709: The functional characteristics of the service and quality-of-service characteristics. Service-oriented architecture aims to allow users to combine large chunks of functionality to form applications which are built purely from existing services and combining them in an ad hoc manner. A service presents a simple interface to the requester that abstracts away the underlying complexity acting as a black box. Further users can also access these independent services without any knowledge of their internal implementation. The related buzzword service-orientation promotes loose coupling between services. SOA separates functions into distinct units, or services, which developers make accessible over

7373-544: The implementation of the language-specific service. SOA-based systems can therefore function independently of development technologies and platforms (such as Java, .NET, etc.). Services written in C# running on .NET platforms and services written in Java running on Java EE platforms, for example, can both be consumed by a common composite application (or client). Applications running on either platform can also consume services running on

7474-638: The information objects are data about Data Elements, Value Domains, and other reusable semantic and representational information objects that describe the meaning and technical details of a data item. This standard also prescribes the details for a metadata registry, and for registering and administering the information objects within a Metadata Registry. ISO/IEC 11179 Part 3 also has provisions for describing compound structures that are derivations of other data elements, for example through calculations, collections of one or more data elements, or other forms of derived data. While this standard describes itself originally as

7575-417: The level of contribution and the responsibilities. Moreover, various metadata about scientific outputs can be created or complemented – for instance, scite.ai attempts to track and link citations of papers as 'Supporting', 'Mentioning' or 'Contrasting' the study. Other examples include developments of alternative metrics – which, beyond providing help for assessment and findability, also aggregate many of

7676-434: The location the photo was taken from may also be included. Photographic Metadata Standards are governed by organizations that develop the following standards. They include, but are not limited to: Metadata is particularly useful in video, where information about its contents (such as transcripts of conversations and text descriptions of its scenes) is not directly understandable by a computer, but where an efficient search of

7777-409: The macro (service) level rather than micro (classes) level. It can also simplify interconnection to—and usage of—existing IT (legacy) assets. With SOA, the idea is that an organization can look at a problem holistically. A business has more overall control. Theoretically there would not be a mass of developers using whatever tool sets might please them. But rather they would be coding to a standard that

7878-438: The metadata application is manifold, covering a large variety of fields, there are specialized and well-accepted models to specify types of metadata. Bretherton & Singley (1994) distinguish between two distinct classes: structural/control metadata and guide metadata. Structural metadata describes the structure of database objects such as tables, columns, keys and indexes. Guide metadata helps humans find specific items and

7979-463: The metadata of scientific publications for various visualizations and aggregation features such as providing a simple user interface summarizing literature about a specific feature of the SARS-CoV-2 virus using Wikidata 's "main subject" property. In research labor, transparent metadata about authors' contributions to works have been proposed – e.g. the role played in the production of the paper,

8080-524: The metadata. Structural metadata commonality is also of paramount importance in data model development and in database design . Metadata (metacontent) syntax refers to the rules created to structure the fields or elements of metadata (metacontent). A single metadata scheme may be expressed in a number of different markup or programming languages, each of which requires a different syntax. For example, Dublin Core may be expressed in plain text, HTML , XML , and RDF . A common example of (guide) metacontent

8181-720: The model number, shutter speed, etc., and some enable you to edit it; this functionality has been available on most Nikon DSLRs since the Nikon D3 , on most new Canon cameras since the Canon EOS 7D , and on most Pentax DSLRs since the Pentax K-3. Metadata can be used to make organizing in post-production easier with the use of key-wording. Filters can be used to analyze a specific set of photographs and create selections on criteria like rating or capture time. On devices with geolocation capabilities like GPS (smartphones in particular),

8282-683: The museum community began in the late 1990s with the development of standards such as Categories for the Description of Works of Art (CDWA), Spectrum, CIDOC Conceptual Reference Model (CRM), Cataloging Cultural Objects (CCO) and the CDWA Lite XML schema. These standards use HTML and XML markup languages for machine processing, publication and implementation. The Anglo-American Cataloguing Rules (AACR), originally developed for characterizing books, have also been applied to cultural objects, works of art and architecture. Standards, such as

8383-427: The numbers themselves can be perceived as the data. But if given the context that this database is a log of a book collection, those 13-digit numbers may now be identified as ISBNs   –  information that refers to the book, but is not itself the information within the book. The term "metadata" was coined in 1968 by Philip Bagley, in his book "Extension of Programming Language Concepts" where it

8484-635: The object by cultural documentarians. The established institutional cataloging practices, goals, and expertise of cultural documentarians and database structure also influence the information ascribed to cultural objects and the ways in which cultural objects are categorized. Additionally, museums often employ standardized commercial collection management software that prescribes and limits the ways in which archivists can describe artworks and cultural objects. As well, collecting institutions and museums use Controlled Vocabularies to describe cultural objects and artworks in their collections. Getty Vocabularies and

8585-401: The offspring of SOA). There are no industry standards relating to the exact composition of a service-oriented architecture, although many industry sources have published their own principles. Some of these include the following: Each SOA building block can play any of the three roles: The service consumer–provider relationship is governed by a standardized service contract , which has

8686-576: The other as web services that facilitate reuse. Managed environments can also wrap COBOL legacy systems and present them as software services. High-level programming languages such as BPEL and specifications such as WS-CDL and WS-Coordination extend the service concept by providing a method of defining and supporting orchestration of fine-grained services into more coarse-grained business services, which architects can in turn incorporate into workflows and business processes implemented in composite applications or portals . Service-oriented modeling

8787-439: The primitive and out-of-scope services are stubs, while the remainder of the mesh is test deployments of full services. As each interface is fully documented with its own full set of regression test documentation, it becomes simple to identify problems in test services. Testing evolves to merely validate that the test service operates according to its documentation, and finds gaps in documentation and test cases of all services within

8888-588: The public discussions about a scientific paper on social media such as Reddit , citations on Misplaced Pages , and reports about the study in the news media – and a call for showing whether or not the original findings are confirmed or could get reproduced . Metadata in a museum context is the information that trained cultural documentation specialists, such as archivists , librarians , museum registrars and curators , create to index, structure, describe, identify, or otherwise specify works of art, architecture, cultural objects and their images. Descriptive metadata

8989-516: The purposes of discovery. The original set of 15 classic metadata terms, known as the Dublin Core Metadata Element Set are endorsed in the following standards documents: The W3C Data Catalog Vocabulary (DCAT) is an RDF vocabulary that supplements Dublin Core with classes for Dataset, Data Service, Catalog, and Catalog Record. DCAT also uses elements from FOAF, PROV-O, and OWL-Time. DCAT provides an RDF model to support

9090-566: The recommendation of Version 1.2 from the W3C (World Wide Web Consortium) in 2003. These standards (also referred to as web service specifications ) also provide greater interoperability and some protection from lock-in to proprietary vendor software. One can, however, also implement SOA using any other service-based technology, such as Jini , CORBA , Internet Communications Engine , REST , or gRPC . Architectures can operate independently of specific technologies and can therefore be implemented using

9191-452: The registration and administration portion of the standard. The Geospatial community has a tradition of specialized geospatial metadata standards, particularly building on traditions of map- and image-libraries and catalogs. Formal metadata is usually essential for geospatial data, as common text-processing approaches are not applicable. The Dublin Core metadata terms are a set of vocabulary terms that can be used to describe resources for

9292-406: The same time, emerging open-source XML parsing technologies (such as VTD-XML ) and various XML-compatible binary formats promise to significantly improve SOA performance. Stateful services require both the consumer and the provider to share the same consumer-specific context, which is either included in or referenced by messages exchanged between the provider and the consumer. This constraint has

9393-406: The scheme of things. Another major problem faced by SOA is the lack of a uniform testing framework. There are no tools that provide the required features for testing these services in a service-oriented architecture. The major causes of difficulty are: Application programming interfaces (APIs) are the frameworks through which developers can interact with a web application. Tim O'Reilly coined

9494-493: The search than they really did. Metadata can be stored and managed in a database , often called a metadata registry or metadata repository . However, without context and a point of reference, it might be impossible to identify metadata just by looking at it. For example: by itself, a database containing several numbers, all 13 digits long could be the results of calculations or a list of numbers to plug into an equation  –  without any other context,

9595-440: The term " Web 2.0 " to describe a perceived, quickly growing set of web-based applications. A topic that has experienced extensive coverage involves the relationship between Web 2.0 and service-oriented architectures. SOA is the philosophy of encapsulating application logic in services with a uniformly defined interface and making these publicly available via discovery mechanisms. The notion of complexity-hiding and reuse, but also

9696-474: The term. In these fields, the word metadata is defined as "data about data". While this is the generally accepted definition, various disciplines have adopted their own more specific explanations and uses of the term. Slate reported in 2013 that the United States government's interpretation of "metadata" could be broad, and might include message content such as the subject lines of emails. While

9797-601: The times, origins and destinations of phone calls, electronic messages, instant messages, and other modes of telecommunication, as opposed to message content, is another form of metadata. Bulk collection of this call detail record metadata by intelligence agencies has proven controversial after disclosures by Edward Snowden of the fact that certain Intelligence agencies such as the NSA had been (and perhaps still are) keeping online metadata on millions of internet users for up to

9898-450: The typical structure of a catalog that contains records, each describing a dataset or service. Although not a standard, Microformat (also mentioned in the section metadata on the internet below) is a web-based approach to semantic markup which seeks to re-use existing HTML/XHTML tags to convey metadata. Microformat follows XHTML and HTML standards but is not a standard in itself. One advocate of microformats, Tantek Çelik , characterized

9999-595: The various sources. A GIS is often the platform for deploying an individual node within an SDI. To achieve these objectives, good coordination between all the actors is necessary and the definition of standards is very important. The original example of an SDI is the United States National Spatial Data Infrastructure ( NSDI ) , first mandated in the OMB Circular A-16 in 1996. In Europe since 2007, INSPIRE

10100-439: The web page online. A CD may include metadata providing information about the musicians, singers, and songwriters whose work appears on the disc. In many countries, government organizations routinely store metadata about emails, telephone calls, web pages, video traffic, IP connections, and cell phone locations. Metadata means "data about data". Metadata is defined as the data providing information about one or more aspects of

10201-628: Was described using metadata standards . The first description of "meta data" for computer systems is purportedly noted by MIT's Center for International Studies experts David Griffel and Stuart McIntosh in 1967: "In summary then, we have statements in an object language about subject descriptions of data and token codes for the data. We also have statements in a meta language describing the data relationships and transformations, and ought/is relations between norm and data." Unique metadata standards exist for different disciplines (e.g., museum collections, digital audio files , websites , etc.). Describing

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