IdeaWazaWiki - User contributions [en]

Archive:Data acquisition system

2008-10-02T01:48:25Z

165.228.80.176: /* External links */

{{Confusing|date=December 2006}}

A '''data acquisition system''' is a device designed to measure and log some parameters. The purpose of the data acquisition system is generally the analysis of the logged data and the improvement of the object of measurements. The data acquisition system is normally electronics based, and it is made of hardware and software.
The hardware part is made of sensors, cables and electronics components (among which memory is where information are stored). The software part is made of the data acquisition logic and the analysis software (and some other utilities that can be used to configure the logic or to move data from data acquisition memory to a laptop or to a mainframe computer).
An example: [[Data logging]], carried out by a '''data acquisition system''' (DAS), can be used to measure parameters such as [[temperature]] and [[humidity]] in storage facilities with perishable products; the measurement data are then stored for analysis to improve quality assurance.
Another example: a '''data acquisition system''' can be placed on a race car to measure RPM and vehicle speed to analyze car's behaviour once it's back to pits and improve the car setup.

==Data logging systems==
Data logging systems consist of four elements:

#Measuring output ([[sensor]]s around the vehicle)
#Recording output signals (logger unit)
#Uploading/accessing recorded data ([[telemetry]])
#Analysis of recorded data. (DAQ [[software]])

The 4 elements above have specific requirements which need to physically present and included in the design process. Sensors to measure selected parameters must meet certain specifications, and the routing of the sensor [[cable]]s ensures they will not suffer from [[electromagnetic]] interference from other electronic systems. The DAQ unit (including [[memory]]) and the link from the DAQ unit to the operating platform to upload the acquired data via a [[hardwire]] cable or telemetry also must conform to requirements.

Most [[race car]]s use two types of telemetry. The first is sent to the [[engineer]]s in the pits every time the vehicle acquires more than 50[[megabyte|Mb]] of data, containing an insight into the state of the vehicle. The second is transferred each time the vehicle is in the [[pit stop|pit lane]], providing information on every part of the vehicle. With the most advanced telemetry, the data are sent constantly for analysis through a [[transmitter]] as long as a good connection is present usually through a hovering [[helicopter]] (not always possible in parts of certain [[raceways]] due to an [[overpass]] obstruction).

The [[operating platform]] is required to include specialist analysis software to view the data, usually in the form of various [[graph]]s to improve and develop the performance of the key areas and operation parameters of the vehicles running conditions. The most advanced software in [[Formula 1]] has been developed by McLaren Electronics known as Advanced Telemetry Linked Acquisition System, which displays graphs of each of the vehicle's systems on the exact section of track, in a [[Real-time computing|real time]] format. The benefits of using such a system include the fact that the parameters which can be recorded for analysis cover the whole set-up of the race vehicle (up to 127 [[Channel (communications)|channel]]s).

The parameters which are measured and recorded by a data acquisition system are broken into three generic categories, which are also interlinked due to system requirements and the complexity of major components (for example, a wheel [[speed]] sensor not only monitors the wheel speed but also the speed of the vehicle, location on the track and an input to [[traction]] and [[launch control (automotive)|launch control]] systems):

#'''[[Engine]]:''' [[Rev]]s per minute, fuel and [[oil]] pressure, water and oil temperature, [[turbo charger]] boost pressure, [[exhaust]] gas temperature, [[battery (electricity)|battery]] voltage, inlet air temperature and [[throttle]] position sensor.
#'''[[Chassis]]:''' Wheel speed, steering angle, [[lateral]] and [[longitudinal]] [[G-force]] (applied from braking and cornering), Brake line pressure, damper movement and gear position.
#*'''Advanced Chassis DAS''': Ride height, [[drive shaft]] or [[prop shaft]] [[torque]], [[Suspension (vehicle)|suspension]] loads, tyre pressure and compound temperature, and brake disk temperature. ''Optional'': [[aerodynamic]] parameters, including air speed and local air pressures.
#'''Driver:''' Both engine and chassis-related factors which are controlled by the driver, such as throttle position, gear position, steering angle and brake line pressure or directly controlled parameters such as engine revs per minute, speed and G-force.

The accurate information provided by telemetry sent by DAS in a practice run takes significant fine tuning, such as ensuring the correct [[gear ratio]]s are present according to track layout, or that the engine acceleration speed according to throttle position and sensitivity is set to the required conditions of a race. The engine control system will be programmed with suitable engine maps giving the driver more control of the throttle input. On a track with a large number of corners, the first part of pedal movement would be made very sensitive in order to effectively negotiate the course. On other courses, however, the vehicle might be required to come out of the [[chicanes]] and directly to peak power levels, thus less sensitivity required on the pedal.

The DAS during race time is monitored by engineers in the pit and [[automobile repair shop|garage]] area, who diagnose any faults which may occur. In this case, the DAS is used as an early warning system of potential mechanical failure, allowing the designers and material analysis team to easily distinguish the cause of the fault. This can result in a significant decrease of the danger to a driver.

Race strategists and engineers can use DAS with telemetry in real time for making more informed decisions pertaining to vehicle performance and driver technique. Information about other vehicles on the track can also be captured and added to the data analysis process. Total data from a motor sport event may exceed 80 gigs of storage space. A new technology born from Associate Systems research or artificial intelligence (AI) has increased the safety factor for spectators, drivers, and officials

A good example for critical data acquisition systems in motor sports can be taken from the [[2003 British Grand Prix]], when engineers in the pits observed the loss of pressure from one of Coulthards tyres. The DAS allowed the team to recall him from his practice, resolving the fault before a dangerous situation occurred, likely saving property and life.

“Formula 1 telemetry is the technological lifeblood of the sport, helping the drivers and engineers to better understand how a car functions and how they can optimise its set-up.”{{Fact|date=February 2007}}

== External links ==

[http://www.adinstruments.com/products/data-acquisition/corporate/ Data Acquisition Systems - PowerLab]

Archive:Data acquisition system

2008-09-26T06:32:32Z

165.228.80.176:

{{Confusing|date=December 2006}}

A '''data acquisition system''' is a device designed to measure and log some parameters. The purpose of the data acquisition system is generally the analysis of the logged data and the improvement of the object of measurements. The data acquisition system is normally electronics based, and it is made of hardware and software.
The hardware part is made of sensors, cables and electronics components (among which memory is where information are stored). The software part is made of the data acquisition logic and the analysis software (and some other utilities that can be used to configure the logic or to move data from data acquisition memory to a laptop or to a mainframe computer).
An example: [[Data logging]], carried out by a '''data acquisition system''' (DAS), can be used to measure parameters such as [[temperature]] and [[humidity]] in storage facilities with perishable products; the measurement data are then stored for analysis to improve quality assurance.
Another example: a '''data acquisition system''' can be placed on a race car to measure RPM and vehicle speed to analyze car's behaviour once it's back to pits and improve the car setup.

==Data logging systems==
Data logging systems consist of four elements:

#Measuring output ([[sensor]]s around the vehicle)
#Recording output signals (logger unit)
#Uploading/accessing recorded data ([[telemetry]])
#Analysis of recorded data. (DAQ [[software]])

The 4 elements above have specific requirements which need to physically present and included in the design process. Sensors to measure selected parameters must meet certain specifications, and the routing of the sensor [[cable]]s ensures they will not suffer from [[electromagnetic]] interference from other electronic systems. The DAQ unit (including [[memory]]) and the link from the DAQ unit to the operating platform to upload the acquired data via a [[hardwire]] cable or telemetry also must conform to requirements.

Most [[race car]]s use two types of telemetry. The first is sent to the [[engineer]]s in the pits every time the vehicle acquires more than 50[[megabyte|Mb]] of data, containing an insight into the state of the vehicle. The second is transferred each time the vehicle is in the [[pit stop|pit lane]], providing information on every part of the vehicle. With the most advanced telemetry, the data are sent constantly for analysis through a [[transmitter]] as long as a good connection is present usually through a hovering [[helicopter]] (not always possible in parts of certain [[raceways]] due to an [[overpass]] obstruction).

The [[operating platform]] is required to include specialist analysis software to view the data, usually in the form of various [[graph]]s to improve and develop the performance of the key areas and operation parameters of the vehicles running conditions. The most advanced software in [[Formula 1]] has been developed by McLaren Electronics known as Advanced Telemetry Linked Acquisition System, which displays graphs of each of the vehicle's systems on the exact section of track, in a [[Real-time computing|real time]] format. The benefits of using such a system include the fact that the parameters which can be recorded for analysis cover the whole set-up of the race vehicle (up to 127 [[Channel (communications)|channel]]s).

The parameters which are measured and recorded by a data acquisition system are broken into three generic categories, which are also interlinked due to system requirements and the complexity of major components (for example, a wheel [[speed]] sensor not only monitors the wheel speed but also the speed of the vehicle, location on the track and an input to [[traction]] and [[launch control (automotive)|launch control]] systems):

#'''[[Engine]]:''' [[Rev]]s per minute, fuel and [[oil]] pressure, water and oil temperature, [[turbo charger]] boost pressure, [[exhaust]] gas temperature, [[battery (electricity)|battery]] voltage, inlet air temperature and [[throttle]] position sensor.
#'''[[Chassis]]:''' Wheel speed, steering angle, [[lateral]] and [[longitudinal]] [[G-force]] (applied from braking and cornering), Brake line pressure, damper movement and gear position.
#*'''Advanced Chassis DAS''': Ride height, [[drive shaft]] or [[prop shaft]] [[torque]], [[Suspension (vehicle)|suspension]] loads, tyre pressure and compound temperature, and brake disk temperature. ''Optional'': [[aerodynamic]] parameters, including air speed and local air pressures.
#'''Driver:''' Both engine and chassis-related factors which are controlled by the driver, such as throttle position, gear position, steering angle and brake line pressure or directly controlled parameters such as engine revs per minute, speed and G-force.

The accurate information provided by telemetry sent by DAS in a practice run takes significant fine tuning, such as ensuring the correct [[gear ratio]]s are present according to track layout, or that the engine acceleration speed according to throttle position and sensitivity is set to the required conditions of a race. The engine control system will be programmed with suitable engine maps giving the driver more control of the throttle input. On a track with a large number of corners, the first part of pedal movement would be made very sensitive in order to effectively negotiate the course. On other courses, however, the vehicle might be required to come out of the [[chicanes]] and directly to peak power levels, thus less sensitivity required on the pedal.

The DAS during race time is monitored by engineers in the pit and [[automobile repair shop|garage]] area, who diagnose any faults which may occur. In this case, the DAS is used as an early warning system of potential mechanical failure, allowing the designers and material analysis team to easily distinguish the cause of the fault. This can result in a significant decrease of the danger to a driver.

Race strategists and engineers can use DAS with telemetry in real time for making more informed decisions pertaining to vehicle performance and driver technique. Information about other vehicles on the track can also be captured and added to the data analysis process. Total data from a motor sport event may exceed 80 gigs of storage space. A new technology born from Associate Systems research or artificial intelligence (AI) has increased the safety factor for spectators, drivers, and officials

A good example for critical data acquisition systems in motor sports can be taken from the [[2003 British Grand Prix]], when engineers in the pits observed the loss of pressure from one of Coulthards tyres. The DAS allowed the team to recall him from his practice, resolving the fault before a dangerous situation occurred, likely saving property and life.

“Formula 1 telemetry is the technological lifeblood of the sport, helping the drivers and engineers to better understand how a car functions and how they can optimise its set-up.”{{Fact|date=February 2007}}

== External links ==

[http://www.adinstruments.com/products/hardware/research/Data*Acquisition*Systems/ Data Acquisition System - PowerLab]

Precipitation (chemistry)

2008-05-26T00:23:35Z

165.228.98.213: /* Representation using chemical equations */

[[Image:Chemical precipitation diagram.png|thumb|right|Chemical Precipitation]]
{{about|a chemical [[separation process]]|other uses|Precipitation (disambiguation)}}
'''Precipitation''' is the formation of a [[solid]] in a [[solution]] during a [[chemical reaction]]. When the reaction occurs, the solid formed is called the '''precipitate''', and the liquid remaining above the solid is called the '''supernate'''.

== Uses of precipitation reactions ==
Precipitation reactions can be used for making [[pigments]], removing [[salts]] from water in [[water treatment]], and for qualitative [[chemical analysis]].

This effect is useful in many [[industrial]] and [[scientific]] applications whereby a chemical reaction may produce a solid that can be collected from the solution by various methods (e.g. [[filtration]], [[decanting]], [[centrifugation]]). Precipitation from a [[solid solution]] is also a useful way to [[precipitation strengthening|strengthen]] [[alloy]]s; this process is known as [[solid solution strengthening]].

== Mechanism ==
Precipitation can occur when an [[solubility|insoluble]] substance is formed in the [[solution (chemistry)|solution]] due to a [[chemical reaction]] or when the solution has been [[supersaturated]] by a [[compound (chemistry)|compound]]. The formation of a precipitate is a sign of a [[chemical change]]. In most situations, the solid forms ("falls") out of the solute phase, and sinks to the bottom of the solution (though it will float if it is less dense than the solvent, or form a [[suspension (chemistry)|suspension]]).

The solid may reach the bottom of a container by means of [[settling]], [[sediment]]ation, or [[centrifugation]].

An important stage of the precipitation process is the onset of [[nucleation]]. The creation of a hypothetical solid [[particle]] includes the formation of an [[interface (chemistry)|interface]], which requires some [[energy (chemistry)|energy]] based on the relative [[surface energy]] of the solid and the solution. If this energy is not available, and no suitable nucleation surface is available, [[supersaturation]] occurs.

== Representation using chemical equations ==
An example of a precipitation reaction: Aqueous [[silver nitrate]] (AgNO3) is added to a solution containing [[potassium chloride]] (KCl) and the precipitation of a white solid, [[silver chloride]] is observed. (Zumdahl, 2005)

:AgNO3 (aq) + KCl (aq) → AgCl (s) + KNO3 (aq)

The silver chloride(AgCl) has formed a solid, which is observed as a precipitate.

This reaction can be written emphasizing the [[dissociation|dissociated]] [[ions]] in a combined solution. This is known as the [[ionic equation]].
:Ag+ (aq) + NO3- (aq) + K+ (aq) + Cl- (aq) → AgCl (s) + K+ (aq) + NO3- (aq)

A final way to represent a precipitate reaction is known as a ''net ionic reaction''. In this case, any [[spectator ions]] (those which do not contribute to the reaction) are left out of the formula completely. This simplifies the above equations to the following:
:Ag+ (aq) + Cl- (aq) → AgCl (s)

If centrifuge takes place in the process of a net ionic reaction thana "ryan atom" disperses causing him to be amazing

==Cation sensitivity==
Precipitate formation is useful in the detection of the type of [[cation]] in [[salt]]. To do this, an [[alkali]] first reacts with the unknown salt to produce a precipitate which is the [[hydroxide]] of the unknown salt. To identify the cation, the color of the precipitate and its solubility in excess are noted. Similar processes are often used to separate chemically similar elements, such as the [[Alkali earth metals]].

==Digestion==
Digestion, or ''precipitate ageing'', happens when a freshly-formed precipitate is left, usually at a higher [[temperature]], in the solution from which it is precipitated. It results in cleaner and bigger particles.<ref>{{cite web |url=http://www.ktf-split.hr/glossary/en_o.php?def=digestion |title=Chemical dictionary definition |accessdate=2008-02-26}}</ref> The physico-chemical process underlying digestion is called [[Ostwald ripening]].

==Coprecipitation==
{{main|coprecipitation}}
Coprecipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. It is an important issue in chemical analysis, where it is often undesirable, but in some cases it can be exploited. In [[gravimetric analysis]], it is a problem because undesired impurities often coprecipitate with the analyte, resulting in excess mass. On the other hand, in the analysis of trace elements, as is often the case in [[radiochemistry]], coprecipitation is often the only way of separating an element.

==References==
*Zumdahl, Steven S. ''Chemical Principles.'' 4th ed. New York: Houghton Mifflin Company, 2005.
*Mark Smith ''Principles of Science'' 1993
{{reflist}}
{{refimprove|date=February 2008}}

==Further reading==
*Banert, T., Brenner, G., Peuker, U. A. (2006), Operating parameters of a continuous sono-chemical precipitation reactor, Proc. 5. WCPT, Orlando Fl., 23.-27. April 2006.

==External links==
{{Commonscat|Solid precipitation}}
* [http://www.hielscher.com/ultrasonics/precipitation_01.htm Continuous Precipitation Using Ultrasonication (e.g. for nano-size magnetite particles)]
* http://www.answers.com/supernatant

[[Category:Separation processes]]
[[Category:Chemical processes]]

[[ca:Precipitació (química)]]
[[da:Fældningsreaktion]]
[[de:Fällung]]
[[es:Precipitado]]
[[fr:Précipité]]
[[gl:Precipitación (reacción)]]
[[it:Precipitazione (chimica)]]
[[he:תגובת שיקוע]]
[[nl:Neerslag (scheikunde)]]
[[ja:沈殿]]
[[no:Fellingsreaksjon]]
[[nn:Fellingsreaksjon]]
[[pt:Precipitação (química)]]
[[ru:Преципитат (химия)]]
[[su:Présipitasi]]
[[sv:Utfällning]]
[[ur:عمل ترسیب]]
[[zh:沉淀]]

Precipitation (chemistry)

2008-05-26T00:21:08Z

165.228.98.213: /* Representation using chemical equations */

[[Image:Chemical precipitation diagram.png|thumb|right|Chemical Precipitation]]
{{about|a chemical [[separation process]]|other uses|Precipitation (disambiguation)}}
'''Precipitation''' is the formation of a [[solid]] in a [[solution]] during a [[chemical reaction]]. When the reaction occurs, the solid formed is called the '''precipitate''', and the liquid remaining above the solid is called the '''supernate'''.

== Uses of precipitation reactions ==
Precipitation reactions can be used for making [[pigments]], removing [[salts]] from water in [[water treatment]], and for qualitative [[chemical analysis]].

This effect is useful in many [[industrial]] and [[scientific]] applications whereby a chemical reaction may produce a solid that can be collected from the solution by various methods (e.g. [[filtration]], [[decanting]], [[centrifugation]]). Precipitation from a [[solid solution]] is also a useful way to [[precipitation strengthening|strengthen]] [[alloy]]s; this process is known as [[solid solution strengthening]].

== Mechanism ==
Precipitation can occur when an [[solubility|insoluble]] substance is formed in the [[solution (chemistry)|solution]] due to a [[chemical reaction]] or when the solution has been [[supersaturated]] by a [[compound (chemistry)|compound]]. The formation of a precipitate is a sign of a [[chemical change]]. In most situations, the solid forms ("falls") out of the solute phase, and sinks to the bottom of the solution (though it will float if it is less dense than the solvent, or form a [[suspension (chemistry)|suspension]]).

The solid may reach the bottom of a container by means of [[settling]], [[sediment]]ation, or [[centrifugation]].

An important stage of the precipitation process is the onset of [[nucleation]]. The creation of a hypothetical solid [[particle]] includes the formation of an [[interface (chemistry)|interface]], which requires some [[energy (chemistry)|energy]] based on the relative [[surface energy]] of the solid and the solution. If this energy is not available, and no suitable nucleation surface is available, [[supersaturation]] occurs.

== Representation using chemical equations ==
An example of a precipitation reaction: Aqueous [[silver nitrate]] (AgNO3) is added to a solution containing [[potassium chloride]] (KCl) and the precipitation of a white solid, [[silver chloride]] is observed. (Zumdahl, 2005)

:AgNO3 (aq) + KCl (aq) → AgCl (s) + KNO3 (aq)

The silver chloride(AgCl) has formed a solid, which is observed as a precipitate.

This reaction can be written emphasizing the [[dissociation|dissociated]] [[ions]] in a combined solution. This is known as the [[ionic equation]].
:Ag+ (aq) + NO3- (aq) + K+ (aq) + Cl- (aq) → AgCl (s) + K+ (aq) + NO3- (aq)

A final way to represent a precipitate reaction is known as a ''net ionic reaction''. In this case, any [[spectator ions]] (those which do not contribute to the reaction) are left out of the formula completely. This simplifies the above equations to the following:
:Ag+ (aq) + Cl- (aq) → AgCl (s)

Jarred is also super cooooool!!!

==Cation sensitivity==
Precipitate formation is useful in the detection of the type of [[cation]] in [[salt]]. To do this, an [[alkali]] first reacts with the unknown salt to produce a precipitate which is the [[hydroxide]] of the unknown salt. To identify the cation, the color of the precipitate and its solubility in excess are noted. Similar processes are often used to separate chemically similar elements, such as the [[Alkali earth metals]].

==Digestion==
Digestion, or ''precipitate ageing'', happens when a freshly-formed precipitate is left, usually at a higher [[temperature]], in the solution from which it is precipitated. It results in cleaner and bigger particles.<ref>{{cite web |url=http://www.ktf-split.hr/glossary/en_o.php?def=digestion |title=Chemical dictionary definition |accessdate=2008-02-26}}</ref> The physico-chemical process underlying digestion is called [[Ostwald ripening]].

==Coprecipitation==
{{main|coprecipitation}}
Coprecipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. It is an important issue in chemical analysis, where it is often undesirable, but in some cases it can be exploited. In [[gravimetric analysis]], it is a problem because undesired impurities often coprecipitate with the analyte, resulting in excess mass. On the other hand, in the analysis of trace elements, as is often the case in [[radiochemistry]], coprecipitation is often the only way of separating an element.

==References==
*Zumdahl, Steven S. ''Chemical Principles.'' 4th ed. New York: Houghton Mifflin Company, 2005.
*Mark Smith ''Principles of Science'' 1993
{{reflist}}
{{refimprove|date=February 2008}}

==Further reading==
*Banert, T., Brenner, G., Peuker, U. A. (2006), Operating parameters of a continuous sono-chemical precipitation reactor, Proc. 5. WCPT, Orlando Fl., 23.-27. April 2006.

==External links==
{{Commonscat|Solid precipitation}}
* [http://www.hielscher.com/ultrasonics/precipitation_01.htm Continuous Precipitation Using Ultrasonication (e.g. for nano-size magnetite particles)]
* http://www.answers.com/supernatant

[[Category:Separation processes]]
[[Category:Chemical processes]]

[[ca:Precipitació (química)]]
[[da:Fældningsreaktion]]
[[de:Fällung]]
[[es:Precipitado]]
[[fr:Précipité]]
[[gl:Precipitación (reacción)]]
[[it:Precipitazione (chimica)]]
[[he:תגובת שיקוע]]
[[nl:Neerslag (scheikunde)]]
[[ja:沈殿]]
[[no:Fellingsreaksjon]]
[[nn:Fellingsreaksjon]]
[[pt:Precipitação (química)]]
[[ru:Преципитат (химия)]]
[[su:Présipitasi]]
[[sv:Utfällning]]
[[ur:عمل ترسیب]]
[[zh:沉淀]]

Precipitation (chemistry)

2008-05-26T00:20:26Z

165.228.98.213: /* Mechanism */

[[Image:Chemical precipitation diagram.png|thumb|right|Chemical Precipitation]]
{{about|a chemical [[separation process]]|other uses|Precipitation (disambiguation)}}
'''Precipitation''' is the formation of a [[solid]] in a [[solution]] during a [[chemical reaction]]. When the reaction occurs, the solid formed is called the '''precipitate''', and the liquid remaining above the solid is called the '''supernate'''.

== Uses of precipitation reactions ==
Precipitation reactions can be used for making [[pigments]], removing [[salts]] from water in [[water treatment]], and for qualitative [[chemical analysis]].

This effect is useful in many [[industrial]] and [[scientific]] applications whereby a chemical reaction may produce a solid that can be collected from the solution by various methods (e.g. [[filtration]], [[decanting]], [[centrifugation]]). Precipitation from a [[solid solution]] is also a useful way to [[precipitation strengthening|strengthen]] [[alloy]]s; this process is known as [[solid solution strengthening]].

== Mechanism ==
Precipitation can occur when an [[solubility|insoluble]] substance is formed in the [[solution (chemistry)|solution]] due to a [[chemical reaction]] or when the solution has been [[supersaturated]] by a [[compound (chemistry)|compound]]. The formation of a precipitate is a sign of a [[chemical change]]. In most situations, the solid forms ("falls") out of the solute phase, and sinks to the bottom of the solution (though it will float if it is less dense than the solvent, or form a [[suspension (chemistry)|suspension]]).

The solid may reach the bottom of a container by means of [[settling]], [[sediment]]ation, or [[centrifugation]].

An important stage of the precipitation process is the onset of [[nucleation]]. The creation of a hypothetical solid [[particle]] includes the formation of an [[interface (chemistry)|interface]], which requires some [[energy (chemistry)|energy]] based on the relative [[surface energy]] of the solid and the solution. If this energy is not available, and no suitable nucleation surface is available, [[supersaturation]] occurs.

Ryan is super coool!!

== Representation using chemical equations ==
An example of a precipitation reaction: Aqueous [[silver nitrate]] (AgNO3) is added to a solution containing [[potassium chloride]] (KCl) and the precipitation of a white solid, [[silver chloride]] is observed. (Zumdahl, 2005)

:AgNO3 (aq) + KCl (aq) → AgCl (s) + KNO3 (aq)

The silver chloride(AgCl) has formed a solid, which is observed as a precipitate.

This reaction can be written emphasizing the [[dissociation|dissociated]] [[ions]] in a combined solution. This is known as the [[ionic equation]].
:Ag+ (aq) + NO3- (aq) + K+ (aq) + Cl- (aq) → AgCl (s) + K+ (aq) + NO3- (aq)

A final way to represent a precipitate reaction is known as a ''net ionic reaction''. In this case, any [[spectator ions]] (those which do not contribute to the reaction) are left out of the formula completely. This simplifies the above equations to the following:
:Ag+ (aq) + Cl- (aq) → AgCl (s)

==Cation sensitivity==
Precipitate formation is useful in the detection of the type of [[cation]] in [[salt]]. To do this, an [[alkali]] first reacts with the unknown salt to produce a precipitate which is the [[hydroxide]] of the unknown salt. To identify the cation, the color of the precipitate and its solubility in excess are noted. Similar processes are often used to separate chemically similar elements, such as the [[Alkali earth metals]].

==Digestion==
Digestion, or ''precipitate ageing'', happens when a freshly-formed precipitate is left, usually at a higher [[temperature]], in the solution from which it is precipitated. It results in cleaner and bigger particles.<ref>{{cite web |url=http://www.ktf-split.hr/glossary/en_o.php?def=digestion |title=Chemical dictionary definition |accessdate=2008-02-26}}</ref> The physico-chemical process underlying digestion is called [[Ostwald ripening]].

==Coprecipitation==
{{main|coprecipitation}}
Coprecipitation is the carrying down by a precipitate of substances normally soluble under the conditions employed. It is an important issue in chemical analysis, where it is often undesirable, but in some cases it can be exploited. In [[gravimetric analysis]], it is a problem because undesired impurities often coprecipitate with the analyte, resulting in excess mass. On the other hand, in the analysis of trace elements, as is often the case in [[radiochemistry]], coprecipitation is often the only way of separating an element.

==References==
*Zumdahl, Steven S. ''Chemical Principles.'' 4th ed. New York: Houghton Mifflin Company, 2005.
*Mark Smith ''Principles of Science'' 1993
{{reflist}}
{{refimprove|date=February 2008}}

==Further reading==
*Banert, T., Brenner, G., Peuker, U. A. (2006), Operating parameters of a continuous sono-chemical precipitation reactor, Proc. 5. WCPT, Orlando Fl., 23.-27. April 2006.

==External links==
{{Commonscat|Solid precipitation}}
* [http://www.hielscher.com/ultrasonics/precipitation_01.htm Continuous Precipitation Using Ultrasonication (e.g. for nano-size magnetite particles)]
* http://www.answers.com/supernatant

[[Category:Separation processes]]
[[Category:Chemical processes]]

[[ca:Precipitació (química)]]
[[da:Fældningsreaktion]]
[[de:Fällung]]
[[es:Precipitado]]
[[fr:Précipité]]
[[gl:Precipitación (reacción)]]
[[it:Precipitazione (chimica)]]
[[he:תגובת שיקוע]]
[[nl:Neerslag (scheikunde)]]
[[ja:沈殿]]
[[no:Fellingsreaksjon]]
[[nn:Fellingsreaksjon]]
[[pt:Precipitação (química)]]
[[ru:Преципитат (химия)]]
[[su:Présipitasi]]
[[sv:Utfällning]]
[[ur:عمل ترسیب]]
[[zh:沉淀]]

Archive:Data acquisition system

2008-02-08T00:30:09Z

165.228.90.99: /* Hardware */

{{Confusing|date=December 2006}}

A '''data acquisition system''' is a device designed to measure and log some parameters. The purpose of the data acquisition system is generally the analysis of the logged data and the improvement of the object of measurements. The data acquisition system is normally electronics based, and it is made of hardware and software.
The hardware part is made of sensors, cables and electronics components (among which memory is where information are stored). The software part is made of the data acquisition logic and the analysis software (and some other utilities that can be used to configure the logic or to move data from data acquisition memory to a laptop or to a mainframe computer).
An example: [[Data logging]], carried out by a '''data acquisition system''' (DAS), can be used to measure parameters such as [[temperature]] and [[humidity]] in storage facilities with perishable products; the measurement data is then stored for analysis to improve quality assurance.
Another example: a '''data acquisition system''' can be placed on a race car to measure RPM and vehicle speed to analyze car's behaviour once it's back to pits and improve the car setup.

==Data logging systems==
Data logging systems consist of four elements:

#Measuring output ([[sensor]]s around the vehicle)
#Recording output signals (logger unit)
#Uploading/accessing recorded data ([[telemetry]])
#Analysis of recorded data. (DAS [[software]])

The 4 elements above have specific requirements which need to physically present and included in the design process. Sensors to measure selected parameters must meet certain specifications, and the routing of the sensor [[cable]]s ensures they will not suffer from [[electromagnetic]] interference from other electronic systems. The DAS unit (including [[memory]]) and the link from the DAS unit to the operating platform to upload the acquired data via a [[hardwire]] cable or telemetry also must conform to requirements.

Most [[race car]]s use two types of telemetry. The first is sent to the [[engineer]]s in the pits every time the vehicle acquires more than 50[[megabyte|Mb]] of data, containing an insight into the state of the vehicle. The second is transferred each time the vehicle is in the [[pit stop|pit lane]], providing information on every part of the vehicle. With the most advanced telemetry, the data is sent constantly for analysis through a [[transmitter]] as long as a good connection is present usually thru a hovering [[helicopter]] (not always possible in parts of certain [[raceways]] due to an [[overpass]] obstruction).

The [[operating platform]] is required to include specialist analysis software to view the data, usually in the form of various [[graph]]s to improve and develop the performance of the key areas and operation parameters of the vehicles running conditions. The most advanced software in [[Formula 1]] has been developed by McLaren Electronics known as Advanced Telemetry Linked Acquisition System, which displays graphs of each of the vehicle's systems on the exact section of track, in a [[real time]] format. The benefits of using such a system include the fact that the parameters which can be recorded for analysis cover the whole set-up of the race vehicle (up to 127 [[Channel (communications)|channel]]s).

The parameters which are measured and recorded by a data acquisition system are broken into three generic categories, which are also interlinked due to system requirements and the complexity of major components (for example, a wheel [[speed]] sensor not only monitors the wheel speed but also the speed of the vehicle, location on the track and an input to [[traction]] and [[launch control (automotive)|launch control]] systems):

#'''[[Engine]]:''' [[Rev]]s per minute, fuel and [[oil]] pressure, water and oil temperature, [[turbo charger]] boost pressure, [[exhaust]] gas temperature, [[battery (electricity)|battery]] voltage, inlet air temperature and [[throttle]] position sensor.
#'''[[Chassis]]:''' Wheel speed, steering angle, [[lateral]] and [[longitudinal]] [[G-force]] (applied from braking and cornering), Brake line pressure, damper movement and gear position.
#*'''Advanced Chassis DAS''': Ride height, [[drive shaft]] or [[prop shaft]] [[torque]], [[Suspension (vehicle)|suspension]] loads, tyre pressure and compound temperature, and brake disk temperature. ''Optional'': [[aerodynamic]] parameters, including air speed and local air pressures.
#'''Driver:''' Both engine and chassis-related factors which are controlled by the driver, such as throttle position, gear position, steering angle and brake line pressure or directly controlled parameters such as engine revs per minute, speed and G-force.

The accurate information provided by telemetry sent by DAS in a practice run takes significant fine tuning, such as ensuring the correct [[gear ratio]]s are present according to track layout, or that the engine acceleration speed according to throttle position and sensitivity is set to the required conditions of a race. The engine control system will be programmed with suitable engine maps giving the driver more control of the throttle input. On a track with a large number of corners, the first part of pedal movement would be made very sensitive in order to effectively negotiate the course. On other courses, however, the vehicle might be required to come out of the [[chicanes]] and directly to peak power levels, thus less sensitivity required on the pedal.

The DAS during race time is monitored by engineers in the pit and [[automobile repair shop|garage]] area, who diagnose any faults which may occur. In this case, the DAS is used as an early warning system of potential mechanical failure, allowing the designers and material analysis team to easily distinguish the cause of the fault. This can result in a significant decrease of the danger to a driver.

Race strategists and engineers can use DAS with telemetry in real time for making more informed decisions pertaining to vehicle performance and driver technique. Information about other vehicles on the track can also be captured and added to the data analysis process. Total data from a motor sport event may exceed 80 gigs of storage space. A new technology born from Associate Systems research or artificial intelligence (AI) has increased the safety factor for spectators, drivers, and officials.

A good example for critical data aqcuisition systems in motor sports can be taken from the [[2003 British Grand Prix]], when engineers in the pits observed the loss of pressure from one of Coulthards tyres. The DAS allowed the team to recall him from his practice, resolving the fault before a dangerous situation occurred, likely saving property and life.

“Formula 1 telemetry is the technological lifeblood of the sport, helping the drivers and engineers to better understand how a car functions and how they can optimise its set-up.”{{Fact|date=February 2007}}

== Hardware ==
;Commercial
:[http://www.mstarlabs.com/ MicroStar ]
:[http://www.iotech.com/ IOTECH ]
:[http://www.ni.com/dataacquisition/ NI ]
:[http://www.measurenet-tech.com/ MeasureNet]
;[http://www.datataker.com/ dataTaker]