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The Product Types Ontology: Class Definition for "Loudspeaker"

This page is part of http://www.productontology.org/, a huge, precise dictionary of product types and brand names for marking up Web sites with schema.org or the GoodRelations e-commerce standard.

Breaking news: schema.org has just implemented our proposal to define an additionalType property with the use of this service in mind!

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http://www.productontology.org/

On this page: Usage(schema.org/Microdata, RDFa, Facebook) Contact Information Caching Policy License Acknowledgments References

pto:Loudspeaker (rdf:type owl:Class)

URI http://www.productontology.org/id/Loudspeaker
rdfs:subClassOf gr:ProductOrService, http://schema.org/Product
rdfs:label Loudspeaker (as a class or brand name of products of services)
Translation(s):  Luidspreker@af;  Altavoz@an;  مكبر صوت@ar;  Altavoz@ast;  Ka ici petakok kitotakan@atj;  Гучнагаварыцель@be;  Високоговорител@bg;  লাউডস্পিকার@bn;  Altaveu@ca; 

rdfs:comment

]] A loudspeaker (or loud-speaker or speaker) is an electroacoustic transducer; a device which converts an electrical audio signal into a corresponding sound. The most widely used type of speaker in the 2010s is the dynamic speaker, invented in 1924 by Edward W. Kellogg and Chester W. Rice. The dynamic speaker operates on the same basic principle as a dynamic microphone, but in reverse, to produce sound from an electrical signal. When an alternating current electrical audio signal is applied to its voice coil, a coil of wire suspended in a circular gap between the poles of a permanent magnet, the coil is forced to move rapidly back and forth due to Faraday's law of induction, which causes a diaphragm (usually conically shaped) attached to the coil to move back and forth, pushing on the air to create sound waves. Besides this most common method, there are several alternative technologies that can be used to convert an electrical signal into sound. The sound source (e.g., a sound recording or a microphone) must be amplified or strengthened with an audio power amplifier before the signal is sent to the speaker. Speakers are typically housed in a speaker enclosure or speaker cabinet which is often a rectangular or square box made of several forms of wood, or sometimes plastic. The enclosure's materials and design play an important role in the quality of the sound. The enclosure generally must be as stiff and non-resonant as practically possible. Where high fidelity reproduction of sound is required, multiple loudspeaker transducers are often mounted in the same enclosure, each reproducing a part of the audible frequency range (picture at right). In this case the individual speakers are referred to as "drivers" and the entire unit is called a loudspeaker. Drivers made for reproducing high audio frequencies are called tweeters, those for middle frequencies are called mid-range drivers, and those for low frequencies are called woofers. Extremely low frequencies (16Hz-~100Hz)may be reproduced by detached subwoofers. Smaller loudspeakers are found in devices such as radios, televisions, portable audio players, computers, and electronic musical instruments. Larger loudspeaker systems are used for music, sound reinforcement in theatres and concert halls, and in public address systems. (Source: Wikipedia, the free encyclopedia, see http://en.wikipedia.org/wiki/Loudspeaker)

Note: The extraction of the abstract from the Wikipedia page may sometimes yield imperfect results. We are improving the algorithm regularly.

is rdfs:domain of gr:category gr:color gr:condition gr:depth gr:hasEAN_UCC-13 gr:hasGTIN-14 gr:hasMPN gr:hasManufacturer gr:hasStockKeepingUnit gr:height gr:isAccessoryOrSparePartFor gr:isConsumableFor gr:isSimilarTo gr:weight gr:width
is rdfs:range of gr:includes gr:isAccessoryOrSparePartFor gr:isConsumableFor gr:isSimilarTo

Note: This is a generic list. Some of the properties may not be applicable to this particular type of object.

Trademark Disclaimer:  Since this service returns class descriptions for potentiall any series of characters, it cannot indicate automatically whether a name is a registered trademark or otherwise protected. We assume no liability for the absence of trademark rights and other damages. See the section "License" below for details.

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Usage

The following shows how to model that you offer to sell [a/an/some] Loudspeaker for $ 19.99.

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Microdata / Use with http://schema.org/Product

One of the most powerful usages of the class definitions from this site is to describe the type of your page and product for the schema.org product markup in Microdata syntax much more precisely.

Simply add the full URI of a class from this site, e.g. http://www.productontology.org/id/Loudspeaker as an additional type as follows:

<div itemscope itemtype="http://schema.org/Product">
    <link itemprop="additionalType" href="http://www.productontology.org/id/Loudspeaker" />
    <!-- other schema.org properties go in here -->
</div>		

Note: In HTML5, it is valid to use the <link> element in the body of a HTML document.

Here is a complete example:

<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
    <title>An offer to sell a / some Loudspeaker</title>
</head>
<body>
<div itemscope itemtype="http://schema.org/Product" itemid="#product">
    <link itemprop="additionalType" href="http://www.productontology.org/id/Loudspeaker" />
    <span itemprop="name">.. a short name for the object ...</span>
    Product description: 
    <span itemprop="description">... a longer description ...</span>
    <div itemprop="offers" itemscope itemtype="http://schema.org/Offer" itemid="#offer">
        <span itemprop="price">$19.99</span> 
        <link itemprop="availability" href="http://schema.org/InStock" />In stock
    </div>
</div>
</body>
</html>

Turtle Syntax

@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .
@prefix pto: <http://www.productontology.org/id/> .
@prefix gr: <http://purl.org/goodrelations/v1#> .
@prefix foo: <http://example.com/> .

# The object
foo:myObject a <http://www.productontology.org/id/Loudspeaker> ;
	a gr:SomeItems ;
	gr:name "... a short name for the object ..."@en ;
	gr:description "... a longer description ..."@en .

# The agent (person or company) who is offering it
foo:ACMECorp a gr:BusinessEntity ;
	gr:legalName "ACME Corp" ;
	gr:offers foo:Offer .
		
# The offer to sell it
foo:Offer a gr:Offering ;
	gr:includes foo:myObject;
	foaf:page <http://URI_of_the_page_containing_the_offer.com>;
	gr:hasBusinessFunction gr:Sell ;
	gr:validFrom "2011-01-24T00:00:00+01:00"^^xsd:dateTime ;
	gr:validThrough "2011-12-24T00:00:00+01:00"^^xsd:dateTime ;
	gr:hasPriceSpecification
         [ a gr:UnitPriceSpecification ;
           gr:hasCurrency "USD"^^xsd:string ;
           gr:hasCurrencyValue "19.99"^^xsd:float ;
           gr:validThrough "2011-12-24T00:00:00+01:00"^^xsd:dateTime ] .

Note: Replace gr:SomeItems (http://purl.org/goodrelations/v1#SomeItems) by gr:Individual if you are describing a unique object of that kind (e.g. antique furniture).

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RDFa

<!DOCTYPE html>
<html version="HTML+RDFa 1.1" xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
    <title>An offer to sell a / some Loudspeaker</title>
</head>
<body>
<div xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
     xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
     xmlns:foaf="http://xmlns.com/foaf/0.1/"
     xmlns:gr="http://purl.org/goodrelations/v1#"
     xmlns:pto="http://www.productontology.org/id/"
     xmlns:foo="http://example.com/"
     xmlns:xsd="http://www.w3.org/2001/XMLSchema#">

<!-- The agent (person or company) who is offering it -->
   <div about="#ACMECorp" typeof="gr:BusinessEntity">
      <div property="gr:legalName">ACME Corp</div>
      <div rel="gr:offers">
<!-- The offer to sell it -->	
         <div about="#offer" typeof="gr:Offering">
            <div rel="gr:hasBusinessFunction" resource="http://purl.org/goodrelations/v1#Sell"></div>
            <div rel="gr:includes">
<!-- The object -->	
               <div about="#myObject" typeof="http://www.productontology.org/id/Loudspeaker">
                  <div rel="rdf:type" resource="http://purl.org/goodrelations/v1#SomeItems"></div>
                  <div property="gr:description" xml:lang="en">... a longer description ...</div>
                  <div property="gr:name" xml:lang="en">.. a short name for the object ...</div>
               </div>
            </div>
            <div rel="foaf:page" resource="http://URI_of_the_page_containing_the_offer"></div>
            <div rel="gr:hasPriceSpecification">
               <div typeof="gr:UnitPriceSpecification">
                  <div property="gr:hasCurrency" content="USD" datatype="xsd:string">$ </div>
                  <div property="gr:hasCurrencyValue" datatype="xsd:float">19.99</div>
                  <div property="gr:validThrough" content="2011-12-24T00:00:00+01:00" 
					   datatype="xsd:dateTime"></div>
               </div>
            </div>
            <div property="gr:validFrom" content="2011-01-24T00:00:00+01:00"
                 datatype="xsd:dateTime"></div>
            <div property="gr:validThrough" content="2011-12-24T00:00:00+01:00"
                 datatype="xsd:dateTime"></div>
         </div>
      </div>
   </div>
</div>
</body>
</html>

Note: Replace gr:SomeItems (http://purl.org/goodrelations/v1#SomeItems) by gr:Individual if you are describing a unique object of that kind (e.g. antique furniture).

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RDF/XML

<?xml version="1.0" encoding="UTF-8" ?>
<rdf:RDF xmlns:gr="http://purl.org/goodrelations/v1#" 
  xmlns:pto="http://www.productontology.org/id/" 
  xmlns:xsd="http://www.w3.org/2001/XMLSchema#" 
  xmlns:foaf="http://xmlns.com/foaf/0.1/" 
  xmlns:foo="http://example.com/" 
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<!-- The object -->
  <rdf:Description rdf:about="http://example.com/myObject">
    <rdf:type rdf:resource="http://www.productontology.org/id/Loudspeaker"/>    
    <rdf:type rdf:resource="http://purl.org/goodrelations/v1#SomeItems"/>
    <gr:name xml:lang="en">... a short name for the object ...</gr:name>
    <gr:description xml:lang="en">... a longer description ...</gr:description>
  </rdf:Description>
<!-- The agent (person or company) who is offering it -->
  <gr:BusinessEntity rdf:about="http://example.com/ACMECorp">
    <gr:legalName>ACME Corp</gr:legalName>
    <gr:offers rdf:resource="http://example.com/Offer" />
  </gr:BusinessEntity>
<!-- The offer to sell it -->   
  <gr:Offering rdf:about="http://example.com/Offer">
    <gr:includes rdf:resource="http://example.com/myObject" />
    <foaf:page rdf:resource="http://URI_of_the_page_containing_the_offer"/>
    <gr:hasBusinessFunction rdf:resource="http://purl.org/goodrelations/v1#Sell"/>
    <gr:validFrom rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">
      2011-01-24T00:00:00+01:00</gr:validFrom>
    <gr:validThrough rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">
      2011-12-24T00:00:00+01:00</gr:validThrough>
    <gr:hasPriceSpecification>
      <gr:UnitPriceSpecification>
        <gr:hasCurrency rdf:datatype="http://www.w3.org/2001/XMLSchema#string">USD</gr:hasCurrency>
        <gr:hasCurrencyValue rdf:datatype="http://www.w3.org/2001/XMLSchema#float">19.99</gr:hasCurrencyValue>
        <gr:validThrough rdf:datatype="http://www.w3.org/2001/XMLSchema#dateTime">
          2011-12-24T00:00:00+01:00</gr:validThrough>
      </gr:UnitPriceSpecification>
    </gr:hasPriceSpecification>
  </gr:Offering>

</rdf:RDF>

Note: Replace gr:SomeItems (http://purl.org/goodrelations/v1#SomeItems) by gr:Individual if you are describing a unique object of that kind (e.g. antique furniture).

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SPARQL Query

prefix foaf: <http://xmlns.com/foaf/0.1/> 
prefix xsd: <http://www.w3.org/2001/XMLSchema#> 
prefix pto: <http://www.productontology.org/id/> 
prefix gr: <http://purl.org/goodrelations/v1#> 
prefix foo: <http://example.com/> 

# Find the cheapest offer for a Loudspeaker

SELECT * WHERE{
?company gr:offers ?offer .
?offer a gr:Offering .
?offer gr:hasBusinessFunction gr:Sell .
OPTIONAL {?offer rdfs:label ?label } .
OPTIONAL {?offer gr:name ?label } .
OPTIONAL {?offer rdfs:comment ?label } .
OPTIONAL {?offer gr:description ?label } .
?offer gr:hasPriceSpecification ?p .
?p a gr:UnitPriceSpecification .
?p gr:hasCurrency ?currency .
?p gr:hasCurrencyValue ?price .
?offer gr:includes ?product .
?product a <http://www.productontology.org/id/Loudspeaker> .
}
ORDER BY (?price)
LIMIT 10

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Facebook Open Graph Protocol

You can also use the class definitions from this site for better describing the type of your page or product for the Facebook Open Graph Protocol.

Simply define the namespace prefix pto: in the <html> element of your page

<html version="HTML+RDFa 1.1" 
	xmlns="http://www.w3.org/1999/xhtml" 
	xmlns:pto="http://www.productontology.org/id/" 
	>

and use the compact URI (CURIE) pto:Loudspeaker in combination with og:type as follows:

	<meta property="og:type" content="pto:Loudspeaker"/>

A complete example is here.

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Contact Information

Univ.-Prof. Dr. Martin Hepp

E-Business and Web Science Research Group
Chair of General Management and E-Business
Universität der Bundeswehr München
Werner-Heisenberg-Weg 39
D-85579 Neubiberg, Germany

Phone: +49 89 6004-4217
eMail: mhepp(at)computer.org (preferred mode of communication)
Web: http://www.heppnetz.de/
Web: http://www.unibw.de/ebusiness/

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Caching Policy

In order to minimize the load on the Wikipedia API, all requests are cached internally for 72 hours. This means that changes to the English Wikipedia will be available in this service within 72 hours or less if the same entry has been requested before. Classes not requested within the last six hours are always guaranteed to be in sync with the latest version in Wikipedia.

The RDF/XML dump file is updated every 12 hours only.

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License

The class definition text is taken from Wikipedia, the free encyclopedia under a Creative Commons Attribution-ShareAlike 3.0 Unported (CC BY-SA 3.0) license. Accordingly, the ontology class definitions are available under the very same license.

Trademark Disclaimer:  Since this service returns class descriptions for potentially any series of characters, it cannot indicate automatically whether a name is a registered trademark or otherwise protected. If you want us to block a certain name, please send your request including proof of your rights on the name to our contact address listed below.. Any of the trademarks, service marks, collective marks, design rights or similar rights that are mentioned, used, or cited in this service are the property of their respective owners. Their use here does not imply that you may use them for any purpose other than for the same or a similar informational use as contemplated by the original authors of the underlying Wikipedia articles under the CC-BY-SA and GFDL licensing schemes. Productontology.org is neither endorsed by nor affiliated with any of the holders of any such rights and as such cannot grant any rights to use any otherwise protected materials. Your use of any such or similar incorporeal property is at your own risk.

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Acknowledgements

Thanks to Stefano Bertolo, Julien Chaumond, Bob Ferris, Kingsley Idehen, Axel Polleres, Andreas Radinger, Alex Stolz, and Giovanni Tummarello for very valuable feedback, and to Katharina Siorpaes and Daniel Bachlechner, who contributed to the initial analysis of the stability of Wikipedia URIs back in 2007.

The work on The Product Types Ontology has been supported by the German Federal Ministry of Research (BMBF) by a grant under the KMU Innovativ program as part of the Intelligent Match project (FKZ 01IS10022B).

BMBF logo

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References

Wikipedia: Loudspeaker, available at http://en.wikipedia.org/wiki/Loudspeaker.

Hepp, Martin: GoodRelations: An Ontology for Describing Products and Services Offers on the Web, Proceedings of the 16th International Conference on Knowledge Engineering and Knowledge Management (EKAW2008), Acitrezza, Italy, September 29 - October 3, 2008, Springer LNCS, Vol 5268, pp. 332-347.

Hepp, Martin; Siorpaes, Katharina; Bachlechner, Daniel: Harvesting Wiki Consensus: Using Wikipedia Entries as Vocabulary for Knowledge Management, IEEE Internet Computing, Vol. 11, No. 5, pp. 54-65, Sept-Oct 2007.

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