ratio of word probabilities predicted from brain for church and chimney

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church

chimney

top 10 words in brain distribution (in article):
city build house store town home design world term bus top 10 words in brain distribution (in article):
build wood structure wall design city form type floor house

top 10 words in brain distribution (not in article):
material street state people wood Unite floor type form love top 10 words in brain distribution (not in article):
material cell paint size surface window tree frame store plastic

times more probable under church 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under chimney
(words not in the model)

Pisgah Baptist Church, a typical Protestant church in rural America. Førde Church, a typical Protestant church in Norway. Interior of church in Malancrav, Romania The First Baptist Church of Austell. Located in Austell, G.A., U.S.A. A church in France being fired at during the First World War A church building'" is a building or structure whose primary purpose is to facilitate the meeting of a church. Originally, Christians met in synagogues and in one another's homes. As Christianity grew and became more accepted by governments, rooms, and eventually entire buildings, were set aside for the explicit purpose of Christian worship. Traditional church buildings are often in the shape of a cross, and frequently have a tower or dome. More modern church buildings have a variety of architectural styles and layouts; many buildings that were designed for other purposes have now been converted for church use, and similarly many original church buildings have been put to other uses. Early development. The church of Saint Simon in Aleppo, Syria is considered to be one of the oldest surviving church buildings in the world. The first Christians were, like Jesus, Jews resident in Israel who worshiped on occasion in the Temple in Jerusalem and weekly in local synagogues. Temple worship was a ritual involving sacrifice, occasionally including the sacrifice of animals in atonement for sin, offered to Yahweh. The New Testament includes many references to Jesus visiting the Temple, the first time as an infant with his parents.The early history of the synagogue is obscure, but it seems to be an institution developed for public Jewish worship during the Babylonian captivity when the Jews did not have access to the Jerusalem Temple for ritual sacrifice. Instead, they developed a daily and weekly service of readings from the Torah or the prophets followed by commentary. This could be carried out in a house if the attendance was small enough, and in many towns of the Diaspora that was the case. In others, more elaborate architectural settings developed, sometimes by converting a house and sometimes by converting a previously public building. The minimum requirements seem to have been a meeting room with adequate seating, a case for the Torah scrolls, and a raised platform for the reader and preacher. Jesus himself participated in this sort of service as a reader and commentator (see Gospel of Luke 4: 16-24) and his followers probably remained worshipers in synagogues in some cities. However, following the destruction of the Temple in Jerusalem in 70, the new Christian movement and Judaism increasingly parted ways. The Church became overwhelmingly Gentile sometime in the 4th century. The Syrian city of Dura-Europos on the West bank of the Euphrates was an outpost town between the Roman and Parthian empires. During a siege by Parthian troops in A.D. 257 the buildings in the outermost blocks of the city grid were partially destroyed and filled with rubble to reinforce the city wall. Thus were preserved and securely dated the earliest decorated church and a synagogue decorated with extensive wall paintings. Both had been converted from earlier private buildings. The church at Dura Europos has a special room dedicated for baptisms with a large baptismal font. Churches in medieval Europe. During the 11th through 14th centuries, a wave of building of cathedrals and smaller parish churches occurred across Western Europe. In addition to being a place of worship, the cathedral or parish church was used by the community in other ways. It could serve as a meeting place for guilds or a hall for banquets. Mystery plays were sometimes performed in cathedrals, and cathedrals might also be used for fairs. The church could be used as a place to thresh and store grain. Architecture. A common architecture for churches is the shape of a cross (a long central rectangle, with side rectangles, and a rectangle in front for the altar space or sanctuary). These churches also often have a dome or other large vaulted space in the interior to represent or draw attention to the heavens. Other common shapes for churches include a circle, to represent eternity, or an octagon or similar star shape, to represent the church's bringing light to the world. Another common feature is the spire, a tall tower on the "west" end of the church or over the crossing. Basilica. The Latin word basilica (derived from Greek, "Basiliké Stoà", Royal "Stoa"), was originally used to describe a Roman public building (as in Greece, mainly a tribunal), usually located in the forum of a Roman town. After the Roman Empire became officially Christian, the term came by extension to refer to a large and important church that has been given special ceremonial rites by the Pope. Thus the word retains two senses today, one architectural and the other ecclesiastical. Cathedral. Cathedral of Christ the Saviour (Moscow, Russia). The Cathedral of Saint Sava in Belgrade, Serbia. The largest Orthodox church and one of the largest Cathedrals in the world. A cathedral is a church, usually Roman Catholic, Anglican, or Eastern Orthodox, housing the seat of a bishop. The word cathedral takes its name from the word "cathedra", or Bishop's Throne (In Latin: "ecclesia cathedralis"). The term is sometimes (improperly) used to refer to any church of great size. The church that has the function of cathedral is not of necessity a large building. It might be as small as Christ Church Cathedral, Oxford or Chur Cathedral, Switzerland. But frequently, the cathedral, along with some of the abbey churches, was the largest building in any region. Alternative buildings. Barnabas Community Church, a former army centre now used by a church in Shrewsbury, England. Wasserkirche in Zürich (Switzerland), used as public library (1634-1917) Old and disused church buildings can be seen as an interesting proposition for developers as the architecture and location often provide for attractive homes or city centre entertainment venues On the other hand, many newer Churches have decided to host meetings in public buildings such as schools, universities, cinemas or theatres. There is another trend to convert old buildings for worship use rather than face the construction costs and planning difficulties of a new build. Unusual venues in the UK include an old Tram power station, a former bus garage, an old cinema and bingo hall, a former Territorial Army Drill Hall, a former synagogue and a windmill. A chimney'" is a structure for venting hot flue gases or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney, effect. The space inside a chimney is called a "flue". Chimneys may be found in buildings, steam locomotives and ships. In the US, the term smokestack'" (colloquially, "'stack'") is also used when referring to locomotive chimneys. The term "'funnel'" is generally used for ships' chimneys and sometimes to refer to locomotive chimneys.. Chimneys are tall to increase their draw of air for combustion and to disperse pollutants in the flue gases over a greater area so as to reduce the pollutant concentrations in compliance with regulatory or other limits. History. Romans used tubes inside the walls to draw smoke out of bakeries but real chimneys appeared only in northern Europe in the 12th century. Industrial chimneys became common in the late 18th century. The earliest extant example of an English chimney is at Conisborough Keep in Yorkshire, which dates from 1185 AD. Chimneys have traditionally been built of brick, both in small and large buildings. Early chimneys were of a simple brick construction. Later chimneys were constructed by placing the bricks around tile liners. To control downdrafts venting caps (often called "chimney pots") with a variety of designs are sometimes placed on the top of chimneys. In the eighteenth and nineteenth centuries, the methods used to extract lead from its ore produced large amounts of toxic fumes. In the north of England, long near-horizontal chimneys were built, often more than 3 km (2 mi) long, which typically terminated in a short vertical chimney in a remote location where the fumes would cause less harm. Lead and silver deposits formed on the inside of these long chimneys, and periodically workers would be sent along the chimneys to scrape off these valuable deposits. Construction. Due to brick's limited ability to handle transverse loads, chimneys in houses were often built in a "stack", with a fireplace on each floor of the house sharing a single chimney, often with such a stack at the front and back of the house. Today's central heating systems have made chimney placement less critical, and the use of non-structural gas vent pipe allows a flue gas conduit to be installed around obstructions and through walls. In fact, many modern high-efficiency heating appliances do not require a chimney. Such appliances are typically installed near an outside wall, and a noncombustible wall thimble allows vent pipe to be run directly through the outside wall. Industrial chimneys are commonly referred to as flue gas stacks and are typically external structures, as opposed to being built into the wall of a building. They are generally located adjacent to a steam-generating boiler or industrial furnace and the gases are carried to it with ductwork. Today the use of reinforced concrete has almost entirely replaced brick as a structural component in the construction of industrial chimneys. Refractory bricks are often used as a lining, particularly if the type of fuel being burned generates flue gases containing acids. Modern industrial chimneys sometimes consist of a concrete windshield with a number of flues on the inside. The 300 metre chimney at Sasol Three consists of a 26 metre diameter windshield with four 4.6 metre diameter concrete flues which are lined with refractory bricks built on rings of corbels spaced at 10 metre intervals. The reinforced concrete can be cast by conventional formwork or sliding formwork. The height is to ensure the pollutants are dispersed over a wider area to meet legislative or safety requirements. Chimney tops. A chimney pot is placed on top of the chimney to inexpensively extend the length of the chimney, and to improve the chimney's draft. A chimney with more than one pot on it indicates that there is more than one fireplace on different floors sharing the chimney. A chimney cowl is placed on top of the chimney to prevent birds and squirrels from nesting in the chimney. They often feature a rain guard to keep rain from going down the chimney. A metal wire mesh is often used as a spark arrestor to minimize burning debris from rising out of the chimney and making it onto the roof. Although the masonry inside the chimney can absorb a large amount of moisture which later evaporates, rainwater can collect at the base of the chimney. Sometimes weep holes are placed at the bottom of the chimney to drain out collected water. A chimney cowl or wind directional cap is helmet shaped chimney cap that rotates to align with the wind and prevent a backdraft of smoke and wind back down the chimney. An H-style cap'" (cowl) is a chimney top constructed from chimney pipes shaped like the letter H. It is an age old method to regulate draft in situations where prevailing winds or turbulences cause down draft and backpuffing. Although the "'H cap'" has a distinctive advantage over most other downdraft caps, it fell out of favor because of it bulky looks. It is found mainly in marine use but has been gaining popularity again due to its energy saving functionality. The "'H-cap stabilizes the draft rather than increasing it. Other down draft caps are based on the Venturi effect, solving downdraft problems by increasing the up draft constantly resulting in much higher fuel consumption. A chimney damper is a metal spring door placed at the top of the chimney with a long metal chain that allows you to open and close the chimney from the fireplace. In the late Middle Ages in Western Europe the design of crow-stepped gables arose to allow maintenance access to the chimney top, especially for tall structures such as castles and great manor houses. Chimney draught or draft. When coal, oil, natural gas, wood or any other fuel is combusted in a stove, oven, fireplace, hot water boiler or industrial furnace, the hot combustion product gases that are formed are called flue gases. Those gases are generally exhausted to the ambient outside air through chimneys or industrial flue gas stacks (sometimes referred to as smokestacks). The combustion flue gases inside the chimneys or stacks are much hotter than the ambient outside air and therefore less dense than the ambient air. That causes the bottom of the vertical column of hot flue gas to have a lower pressure than the pressure at the bottom of a corresponding column of outside air. That higher pressure outside the chimney is the driving force that moves the required combustion air into the combustion zone and also moves the flue gas up and out of the chimney. That movement or flow of combustion air and flue gas is called "natural draught draft", "natural ventilation", "chimney effect", or "stack effect". The taller the stack, the more draught or draft is created. Designing chimneys and stacks to provide the correct amount of natural draught or draft involves a number design factors, many of which require trial-and-error reiterative methods. As a "first guess" approximation, the following equation can be used to estimate the natural draught draft flow rate by assuming that the molecular mass (i.e., molecular weight) of the flue gas and the external air are equal and that the frictional pressure and heat losses are negligible: Drawbacks. A characteristic problem of chimneys is they develop deposits of creosote on the walls of the structure when used with wood as a fuel. Some types of wood, such as pine, generate more creosote than others. Deposits of this substance can interfere with the airflow and more importantly, they are flammable and can cause dangerous chimney fires if the deposits ignite in the chimney. Thus, it is recommended — and in some countries even mandatory — that chimneys be inspected annually and cleaned on a regular basis to prevent these problems. The workers who perform this task professionally are called chimney sweeps. In the middle ages in some parts of Europe, a crow-stepped gable design was developed, partially to provide access to chimneys without use of ladders. Masonry (brick) chimneys have also proved particularly susceptible to crumbling during earthquakes. Government housing authorities in quake-prone cities like San Francisco and Los Angeles now recommend building new homes with stud-framed chimneys around a metal flue. Bracing or strapping old masonry chimneys has not proved to be very effective in preventing damage or injury from earthquakes. Perhaps predictably, a new industry provides "faux-brick" facades to cover these modern chimney structures. Other problems include "spalling" brick, in which moisture seeps into the brick and then freezes, cracking and flaking the brick and loosening mortar seals. Dual-use chimneys. Some very high chimneys are used for carrying antennas of mobile phone services and low power FM TV-transmitters. Special attention must be paid to possible corrosion problems if these antennas are near the exhaust of the chimney. In some cases the chimneys of power stations are used also as pylons. However this type of construction is not very common, because of corrosion problems of conductor cables. The Dům Dětí a Mládeže v Modřanech in Prague, Czech Republic is equipped with an observation deck. Cooling tower used as an industrial chimney. At some power stations, which are equipped with plants for the removal of sulfur dioxide and nitrogen oxides, it is possible to use the cooling tower as a chimney. Such cooling towers can be seen in Germany at the Power Station Staudinger Grosskrotzenburg and at the Power Station Rostock. At power stations that are not equipped for removing sulfur dioxide, such usage of cooling towers could result in serious corrosion problems.

church	chimney
top 10 words in brain distribution (in article): city build house store town home design world term bus	top 10 words in brain distribution (in article): build wood structure wall design city form type floor house
top 10 words in brain distribution (not in article): material street state people wood Unite floor type form love	top 10 words in brain distribution (not in article): material cell paint size surface window tree frame store plastic
times more probable under church 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under chimney (words not in the model)
Pisgah Baptist Church, a typical Protestant church in rural America. Førde Church, a typical Protestant church in Norway. Interior of church in Malancrav, Romania The First Baptist Church of Austell. Located in Austell, G.A., U.S.A. A church in France being fired at during the First World War A church building'" is a building or structure whose primary purpose is to facilitate the meeting of a church. Originally, Christians met in synagogues and in one another's homes. As Christianity grew and became more accepted by governments, rooms, and eventually entire buildings, were set aside for the explicit purpose of Christian worship. Traditional church buildings are often in the shape of a cross, and frequently have a tower or dome. More modern church buildings have a variety of architectural styles and layouts; many buildings that were designed for other purposes have now been converted for church use, and similarly many original church buildings have been put to other uses. Early development. The church of Saint Simon in Aleppo, Syria is considered to be one of the oldest surviving church buildings in the world. The first Christians were, like Jesus, Jews resident in Israel who worshiped on occasion in the Temple in Jerusalem and weekly in local synagogues. Temple worship was a ritual involving sacrifice, occasionally including the sacrifice of animals in atonement for sin, offered to Yahweh. The New Testament includes many references to Jesus visiting the Temple, the first time as an infant with his parents.The early history of the synagogue is obscure, but it seems to be an institution developed for public Jewish worship during the Babylonian captivity when the Jews did not have access to the Jerusalem Temple for ritual sacrifice. Instead, they developed a daily and weekly service of readings from the Torah or the prophets followed by commentary. This could be carried out in a house if the attendance was small enough, and in many towns of the Diaspora that was the case. In others, more elaborate architectural settings developed, sometimes by converting a house and sometimes by converting a previously public building. The minimum requirements seem to have been a meeting room with adequate seating, a case for the Torah scrolls, and a raised platform for the reader and preacher. Jesus himself participated in this sort of service as a reader and commentator (see Gospel of Luke 4: 16-24) and his followers probably remained worshipers in synagogues in some cities. However, following the destruction of the Temple in Jerusalem in 70, the new Christian movement and Judaism increasingly parted ways. The Church became overwhelmingly Gentile sometime in the 4th century. The Syrian city of Dura-Europos on the West bank of the Euphrates was an outpost town between the Roman and Parthian empires. During a siege by Parthian troops in A.D. 257 the buildings in the outermost blocks of the city grid were partially destroyed and filled with rubble to reinforce the city wall. Thus were preserved and securely dated the earliest decorated church and a synagogue decorated with extensive wall paintings. Both had been converted from earlier private buildings. The church at Dura Europos has a special room dedicated for baptisms with a large baptismal font. Churches in medieval Europe. During the 11th through 14th centuries, a wave of building of cathedrals and smaller parish churches occurred across Western Europe. In addition to being a place of worship, the cathedral or parish church was used by the community in other ways. It could serve as a meeting place for guilds or a hall for banquets. Mystery plays were sometimes performed in cathedrals, and cathedrals might also be used for fairs. The church could be used as a place to thresh and store grain. Architecture. A common architecture for churches is the shape of a cross (a long central rectangle, with side rectangles, and a rectangle in front for the altar space or sanctuary). These churches also often have a dome or other large vaulted space in the interior to represent or draw attention to the heavens. Other common shapes for churches include a circle, to represent eternity, or an octagon or similar star shape, to represent the church's bringing light to the world. Another common feature is the spire, a tall tower on the "west" end of the church or over the crossing. Basilica. The Latin word basilica (derived from Greek, "Basiliké Stoà", Royal "Stoa"), was originally used to describe a Roman public building (as in Greece, mainly a tribunal), usually located in the forum of a Roman town. After the Roman Empire became officially Christian, the term came by extension to refer to a large and important church that has been given special ceremonial rites by the Pope. Thus the word retains two senses today, one architectural and the other ecclesiastical. Cathedral. Cathedral of Christ the Saviour (Moscow, Russia). The Cathedral of Saint Sava in Belgrade, Serbia. The largest Orthodox church and one of the largest Cathedrals in the world. A cathedral is a church, usually Roman Catholic, Anglican, or Eastern Orthodox, housing the seat of a bishop. The word cathedral takes its name from the word "cathedra", or Bishop's Throne (In Latin: "ecclesia cathedralis"). The term is sometimes (improperly) used to refer to any church of great size. The church that has the function of cathedral is not of necessity a large building. It might be as small as Christ Church Cathedral, Oxford or Chur Cathedral, Switzerland. But frequently, the cathedral, along with some of the abbey churches, was the largest building in any region. Alternative buildings. Barnabas Community Church, a former army centre now used by a church in Shrewsbury, England. Wasserkirche in Zürich (Switzerland), used as public library (1634-1917) Old and disused church buildings can be seen as an interesting proposition for developers as the architecture and location often provide for attractive homes or city centre entertainment venues On the other hand, many newer Churches have decided to host meetings in public buildings such as schools, universities, cinemas or theatres. There is another trend to convert old buildings for worship use rather than face the construction costs and planning difficulties of a new build. Unusual venues in the UK include an old Tram power station, a former bus garage, an old cinema and bingo hall, a former Territorial Army Drill Hall, a former synagogue and a windmill.	A chimney'" is a structure for venting hot flue gases or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the stack, or chimney, effect. The space inside a chimney is called a "flue". Chimneys may be found in buildings, steam locomotives and ships. In the US, the term smokestack'" (colloquially, "'stack'") is also used when referring to locomotive chimneys. The term "'funnel'" is generally used for ships' chimneys and sometimes to refer to locomotive chimneys.. Chimneys are tall to increase their draw of air for combustion and to disperse pollutants in the flue gases over a greater area so as to reduce the pollutant concentrations in compliance with regulatory or other limits. History. Romans used tubes inside the walls to draw smoke out of bakeries but real chimneys appeared only in northern Europe in the 12th century. Industrial chimneys became common in the late 18th century. The earliest extant example of an English chimney is at Conisborough Keep in Yorkshire, which dates from 1185 AD. Chimneys have traditionally been built of brick, both in small and large buildings. Early chimneys were of a simple brick construction. Later chimneys were constructed by placing the bricks around tile liners. To control downdrafts venting caps (often called "chimney pots") with a variety of designs are sometimes placed on the top of chimneys. In the eighteenth and nineteenth centuries, the methods used to extract lead from its ore produced large amounts of toxic fumes. In the north of England, long near-horizontal chimneys were built, often more than 3 km (2 mi) long, which typically terminated in a short vertical chimney in a remote location where the fumes would cause less harm. Lead and silver deposits formed on the inside of these long chimneys, and periodically workers would be sent along the chimneys to scrape off these valuable deposits. Construction. Due to brick's limited ability to handle transverse loads, chimneys in houses were often built in a "stack", with a fireplace on each floor of the house sharing a single chimney, often with such a stack at the front and back of the house. Today's central heating systems have made chimney placement less critical, and the use of non-structural gas vent pipe allows a flue gas conduit to be installed around obstructions and through walls. In fact, many modern high-efficiency heating appliances do not require a chimney. Such appliances are typically installed near an outside wall, and a noncombustible wall thimble allows vent pipe to be run directly through the outside wall. Industrial chimneys are commonly referred to as flue gas stacks and are typically external structures, as opposed to being built into the wall of a building. They are generally located adjacent to a steam-generating boiler or industrial furnace and the gases are carried to it with ductwork. Today the use of reinforced concrete has almost entirely replaced brick as a structural component in the construction of industrial chimneys. Refractory bricks are often used as a lining, particularly if the type of fuel being burned generates flue gases containing acids. Modern industrial chimneys sometimes consist of a concrete windshield with a number of flues on the inside. The 300 metre chimney at Sasol Three consists of a 26 metre diameter windshield with four 4.6 metre diameter concrete flues which are lined with refractory bricks built on rings of corbels spaced at 10 metre intervals. The reinforced concrete can be cast by conventional formwork or sliding formwork. The height is to ensure the pollutants are dispersed over a wider area to meet legislative or safety requirements. Chimney tops. A chimney pot is placed on top of the chimney to inexpensively extend the length of the chimney, and to improve the chimney's draft. A chimney with more than one pot on it indicates that there is more than one fireplace on different floors sharing the chimney. A chimney cowl is placed on top of the chimney to prevent birds and squirrels from nesting in the chimney. They often feature a rain guard to keep rain from going down the chimney. A metal wire mesh is often used as a spark arrestor to minimize burning debris from rising out of the chimney and making it onto the roof. Although the masonry inside the chimney can absorb a large amount of moisture which later evaporates, rainwater can collect at the base of the chimney. Sometimes weep holes are placed at the bottom of the chimney to drain out collected water. A chimney cowl or wind directional cap is helmet shaped chimney cap that rotates to align with the wind and prevent a backdraft of smoke and wind back down the chimney. An H-style cap'" (cowl) is a chimney top constructed from chimney pipes shaped like the letter H. It is an age old method to regulate draft in situations where prevailing winds or turbulences cause down draft and backpuffing. Although the "'H cap'" has a distinctive advantage over most other downdraft caps, it fell out of favor because of it bulky looks. It is found mainly in marine use but has been gaining popularity again due to its energy saving functionality. The "'H-cap stabilizes the draft rather than increasing it. Other down draft caps are based on the Venturi effect, solving downdraft problems by increasing the up draft constantly resulting in much higher fuel consumption. A chimney damper is a metal spring door placed at the top of the chimney with a long metal chain that allows you to open and close the chimney from the fireplace. In the late Middle Ages in Western Europe the design of crow-stepped gables arose to allow maintenance access to the chimney top, especially for tall structures such as castles and great manor houses. Chimney draught or draft. When coal, oil, natural gas, wood or any other fuel is combusted in a stove, oven, fireplace, hot water boiler or industrial furnace, the hot combustion product gases that are formed are called flue gases. Those gases are generally exhausted to the ambient outside air through chimneys or industrial flue gas stacks (sometimes referred to as smokestacks). The combustion flue gases inside the chimneys or stacks are much hotter than the ambient outside air and therefore less dense than the ambient air. That causes the bottom of the vertical column of hot flue gas to have a lower pressure than the pressure at the bottom of a corresponding column of outside air. That higher pressure outside the chimney is the driving force that moves the required combustion air into the combustion zone and also moves the flue gas up and out of the chimney. That movement or flow of combustion air and flue gas is called "natural draught draft", "natural ventilation", "chimney effect", or "stack effect". The taller the stack, the more draught or draft is created. Designing chimneys and stacks to provide the correct amount of natural draught or draft involves a number design factors, many of which require trial-and-error reiterative methods. As a "first guess" approximation, the following equation can be used to estimate the natural draught draft flow rate by assuming that the molecular mass (i.e., molecular weight) of the flue gas and the external air are equal and that the frictional pressure and heat losses are negligible: Drawbacks. A characteristic problem of chimneys is they develop deposits of creosote on the walls of the structure when used with wood as a fuel. Some types of wood, such as pine, generate more creosote than others. Deposits of this substance can interfere with the airflow and more importantly, they are flammable and can cause dangerous chimney fires if the deposits ignite in the chimney. Thus, it is recommended — and in some countries even mandatory — that chimneys be inspected annually and cleaned on a regular basis to prevent these problems. The workers who perform this task professionally are called chimney sweeps. In the middle ages in some parts of Europe, a crow-stepped gable design was developed, partially to provide access to chimneys without use of ladders. Masonry (brick) chimneys have also proved particularly susceptible to crumbling during earthquakes. Government housing authorities in quake-prone cities like San Francisco and Los Angeles now recommend building new homes with stud-framed chimneys around a metal flue. Bracing or strapping old masonry chimneys has not proved to be very effective in preventing damage or injury from earthquakes. Perhaps predictably, a new industry provides "faux-brick" facades to cover these modern chimney structures. Other problems include "spalling" brick, in which moisture seeps into the brick and then freezes, cracking and flaking the brick and loosening mortar seals. Dual-use chimneys. Some very high chimneys are used for carrying antennas of mobile phone services and low power FM TV-transmitters. Special attention must be paid to possible corrosion problems if these antennas are near the exhaust of the chimney. In some cases the chimneys of power stations are used also as pylons. However this type of construction is not very common, because of corrosion problems of conductor cables. The Dům Dětí a Mládeže v Modřanech in Prague, Czech Republic is equipped with an observation deck. Cooling tower used as an industrial chimney. At some power stations, which are equipped with plants for the removal of sulfur dioxide and nitrogen oxides, it is possible to use the cooling tower as a chimney. Such cooling towers can be seen in Germany at the Power Station Staudinger Grosskrotzenburg and at the Power Station Rostock. At power stations that are not equipped for removing sulfur dioxide, such usage of cooling towers could result in serious corrosion problems.