Rope pump

2011-03-27T10:46:38Z

60.243.51.251: /* History */

A '''rope pump''' is a kind of [[pump]] where a loose hanging rope is lowered down into a [[Water well|well]] and drawn up through a long pipe with the bottom immersed in water. On the rope, round disks or knots matching the diameter of the pipe are attached which pull the water to the surface.

==Description==
[[Image:demo rope pump in apeldoorn.jpg|thumb|Rigid valve rope pump]]
A rope pump is a kind of [[pump]] of which the main or most visible component is a continuous piece of rope, in which the rope is integral in raising water from a [[Water well|well]]. Rope pumps are often used in [[Developing country|developing areas]] with the most form consisting of a [[Polyvinyl chloride|PVC]] [[Plastic pressure pipe systems|pipe]] and a rope with flexible or rigid valves. Rope pumps are cheap to build and easy to maintain. One design of rope pump using a solar-powered rope pump can pump 3,000 litres per day using a 80 watt [[solar panel]] .<ref name=SolarAid/> Rope pumps can be powered by low speed petrol/diesel/engines, electricity<ref>{{cite web|url=http://www.daenvis.org/ropepump9.htm|title=Moto Rope pumps|accessdate=2009-04-10}}</ref>, human energy<ref name=thefarm>{{cite web|url=http://www.thefarm.org/charities/i4at/lib2/ropepump.htm|title=Bicycle Rope Pump|accessdate=2009-04-10}}</ref>, wind<ref>{{cite web|url=http://www.gamos.demon.co.uk/just%20gamos%20homepage/henkfnl2.htm|title=THE ROPE WIND PUMP|accessdate=2009-04-10}}</ref> and from solar.<ref name=SolarAid>{{cite web|url=http://www.solar-aid.org/project_water_pump/|title=Solar powered water pump|publisher=Solar Aid|accessdate=2009-04-10}}</ref>

==History==
Chain or washer pumps were used by the [[China|Chinese]] over 1000 years ago. In the 1980's the first steps were made to improve the rope pump using PVC pipes plastic moldings in [[Nicaragua]]<ref name=Ropepumphistory>{{cite web|url=http://www.ropepump.com/his/his.htm|title=history|publisher=Ropepump.com|accessdate=2009-04-10}}</ref>. The technology was rapidly disseminated over the whole country and 25% of the rural population in Nicaragua now use rope pumps. It is also used in other parts of Central America with over 25.000 pumps installed to date<ref>{{cite web|url=http://www.ropepump.com|title=history|publisher=Ropepump.com|accessdate=2009-04-10}}</ref> and is also being used in Africa<ref name=SolarAid/>.
By the end of 2009 more than 4 million people in 20 countries worldwide were using rope pumps for domestic and irrigation water.
But the rope pump

== Construction ==
Rope pumps can use flexible valves, rigid valves or sometimes no valves at all. Flexible valve can be cut piece of bicycle tube. The valves are positioned 20 cm apart on the rope. One disadvantage of flexible valve rope pumps is that different pump builders may use inappropriately sized valves. The thickness of the rubber is also an important factor that differs from place to place.<ref>http://www.scn.org/cmp/modules/wat-ro.htm</ref> Rigid valves using plastic or metal [[Washer (mechanical)|washers]] that fit tightly into the PVC pipe as the rope is dragged through can also be used. If the fit is tight, the washers can be spaced up to half a metre apart. For deeper wells, thinner pipe can be used. These rope pumps often work with a hand crank.<ref>http://web.archive.org/web/20091026235138/http://www.geocities.com/ResearchTriangle/System/7014/rope.html</ref> Valves can also be made from knots in the rope itself.<ref>http://www.appropedia.org/Rope_pump_knots</ref> Valveless pumps rely on friction with water clinging to the rope is moved at high speed, often using a bicycle to produce the required speed. It is a less efficient design but is simpler to construct.<ref name=thefarm>{{cite web|url=http://www.thefarm.org/charities/i4at/lib2/ropepump.htm|title=Bicycle Rope Pump|accessdate=2009-04-10}}</ref>

Rope pump technology is in the public domain and there are no patents pending on it.<ref name=Ropepumphistory/>

==See also==
* [[Chain pump]]

==References==

{{reflist}}

==External links==
* [http://www.ropepumps.org rope pump site]
* [[appropedia:Rope pump|Rope pump]]
* [http://www.amazon.com/dp/1853390224 Robert Lambdon's book]

{{DEFAULTSORT:Rope Pump}}
[[Category:Pumps]]

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[[nl:Touwpomp]]

Software industry

2008-11-08T19:04:00Z

60.243.156.12: /* Overview */

{{globalize}}

The '''software industry''' includes businesses involved in the [[software development|development]], [[software maintenance|maintenance]] and [[software publisher|publication]] of [[computer software]] using any business model. The industry also includes software [[Service (economics)|service]]s, such as [[training]], [[software documentation|documentation]], and [[consultancy|consulting]].

The largest and most profitable of software companies are located in the [[United States]]. As of 2008, the client software industry is dominated by [[Microsoft]]{{Fact|date=March 2008}}. [[Software Magazine]]'s 500 list in 2005 shows the total amount of revenue brought in by software companies per locale, with the highest being [[California]] due to [[Silicon Valley]] and the number of [[Fortune 500]] software companies residing in that area. <ref>[http://www.softwaremag.com/SW500/index.cfm?StartRow=1&RowsPer=50&BusCat_Search=&PrimBus_Search=&PrimBusCat_Search=&RankSort=ASC&CompSort=&trk=n&id=5 Software Magazine 500] (2005)</ref>

== Overview ==
There are several types of businesses in the software industry. The largest and most profitable publish horizontal [[proprietary software]] such as [[Microsoft]], [[SAP]], [[Oracle]], and [[Adobe]]. Others develop vertical-market software intended for a particular sector or niche in the economy such as finance, health care, insurance, retail, automotive manufacturing, and so on. A great deal of specialized software is produced for various niches. Other companies do contract programming to develop unique software for one particular client company, or focus on configuring and customizing suites from large vendors such as SAP or Oracle. And a few companies publish or support [[open source software]].

Developing proprietary software involves [[software licensing]] and the need to protect the software from [[Software cracking|cracking]] and [[Software piracy|piracy]].

== History ==
The software industry started in the early 1960s when universities and businesses first began to use computers and to seek out programs to do certain computing tasks. Many of these programs were written in-house by full-time staff programmers. Some were distributed freely between users of a particular machine for no charge. But others were done on a commercial basis, and the very first standalone software firms started in the United States in 1959-1960.

The industry expanded greatly with the rise of the personal computer in the mid-1970s, which created a growing market for games, applications, and utilities. And gradually the concept that software should be bought and paid for took hold. One of the earliest proponents of this view was [[Bill Gates]], founder of [[Microsoft]].

In the early years of the 21st century, another successful business model has arisen for hosted software, called software as a service, or [[SaaS]]; this was at least the third time this model had been attempted. SaaS reduces the concerns about software piracy, since it can only be accessed through the Web, and by definition no client software is loaded onto the end user's PC.

== Size of the industry ==
[[Software Magazine]]s' ''Software 500 survey'' can be used to gauge the value of the commercial software industry. The ''Software 500 survey'' consists of data from the largest 500 public and private software companies, as ranked by [[Software Magazine]]. Total worldwide revenues in 2007 for companies in the ''Software 500'' list were $451.8 billion, up 14.7% from 2006, when total Software 500 revenue was $394 billion.<ref>[http://www.softwaremag.com/L.cfm?Doc=1175-10/2008 Software Magazine - 2008 Software 500: Innovation Alive and Well</ref>

== Open source software ==
Ironically, the financial return on open source software comes from selling services, such as training and support, rather than the software itself.

Much of the Internet runs on open source software tools and utilities such as [[Linux]], [[Apache HTTP Server|Apache]], [[MySQL]], and [[PHP]], known as the LAMP stack for web servers. Using open source appeals to software developers for three main reasons: low or no cost, access to [[source code]] they can tailor themselves, and a shared community that ensures a generally robust code base, with quick fixes for any new issues that surface.

Despite doing much business in proprietary software, some companies like [[Sun Microsystems]] and [[IBM]] participate in developing free and open source software to deter from [[monopoly|monopolies]] and take a portion of [[market share]] for themselves. [[Netscape]]'s actions are an example of this, and thus [[Firefox]] has become more popular, stealing market share from Internet Explorer.<ref>[[Netscape_Navigator#Fall_of_Netscape]]</ref> But in general, it remains difficult to base a successful business on the open source model.

== See also ==
* [[Professional open-source| Professional Open Source Business Model]]
* [[Computer software]]
* [[Software development]]
* [[Software publisher]]
* [[Software engineering]]
* [[World's largest software companies]]
* [[China Software Industry Association]] (CSIA)

== References ==
<div class="references-small"><references/></div>

== External links ==
{{Wiktionary}}
* [http://www.siia.net/ Software and Information Industry Association website]
* [http://www.softwareceo.com/ SoftwareCEO] the largest online community of software executives in the world
* [http://www.softwaremag.com/ Software Magazine website]
* [http://www.siprofessionals.org/ Software Industry Professionals website]
* [http://www.sao.org/ Software Association of Oregon website]
* [http://software.computerdictionaries.org/ Software Terms] A collection of software dictionaries

[[Category:Industries]]
[[Category:Software industry|*]]

[[ar:صناعة البرمجيات]]
[[es:Industria del software]]
[[th:ซอฟต์แวร์เชิงพาณิชย์]]

IdeaWazaWiki - User contributions [en]

Rope pump

Software industry