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Compressed natural gas

Compressed natural gas (CNG) is a fuel gas mainly composed of methane (CH4), compressed to less than 1% of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of 20 - 25 MPa, usually in cylindrical or spherical shapes.

CNG is used in traditional petrol/internal combustion engine vehicles that have been modified, or in vehicles specifically manufactured for CNG use: either alone (dedicated), with a segregated liquid fuel system to extend range (dual fuel), or in conjunction with another fuel (bi-fuel). It can be used in place of petrol, diesel fuel, and liquefied petroleum gas (LPG). CNG combustion produces fewer undesirable gases than the aforementioned fuels. In comparison to other fuels, natural gas poses less of a threat in the event of a spill, because it is lighter than air and disperses quickly when released. Biomethane, biogas from anaerobic digestion or landfill, can be used.

In response to high fuel prices and environmental concerns, CNG has been used in auto rickshaws, pickup trucks, transit and school buses, and trains.

The cost and placement of fuel storage containers is the major barrier to wider/quicker adoption of CNG as a fuel. It is also why municipal government, public transportation vehicles were the most visible early adopters of it, as they can more quickly amortize the money invested in the new (and usually cheaper) fuel. In spite of these circumstances, the number of vehicles in the world using CNG has grown steadily (30 percent per year). Now, as a result of the industry's steady growth, the cost of such fuel storage cylinders has been brought down to a much more acceptable level. Especially, for the CNG Type 1 and Type 2 cylinders, many countries are able to make reliable and cost effective cylinders for conversion need.

Energy density
CNG's energy density is the same as liquefied natural gas at 53.6 MJ/kg. Its volumetric energy density, 9 MJ/L, is 42 % of that of LNG (22 MJ/L) because it is not liquefied, and is 25 percent that of diesel fuel.

History
Gases provided the original fuel for internal combustion engines. The first experiments with compressed gases took place in France in the 1850s. Natural gas first became a transport fuel during World War I. In the 1960s, Columbia Natural Gas of Ohio tested a CNG carrier. The ship was to carry compressed natural gas in vertical pressure bottles; however, this design failed because of the high cost of the pressure vessels. Since then, there have been attempts at developing a commercially viable CNG carrier. Several competing CNG ocean transport designs have evolved. Each design proposes a unique approach to optimizing gas transport, while using as much off-the-shelf technology as possible, to keep costs competitive.

Motor vehicles

Worldwide, there were 14.8 million natural gas vehicles (NGVs) by 2011, with the largest numbers in Iran (4.07 million), Pakistan (2.85 million), Argentina (2.07 million), Brazil (1.7 million) and India (1.1 million), with the Asia-Pacific region leading with 5.7 million NGVs, followed by Latin America with almost four million vehicles.

Several car and vehicle manufacturers, such as Fiat, Opel/General Motors, Peugeot, Volkswagen, Toyota, Honda, Maruti Suzuki, Hyundai, Tata Motors, and others, sell bi-fuel cars. In 2006 Fiat Siena Tetrafuel was introduced in the Brazilian market, equipped with a 1.4-litre FIRE engine that runs on E100, E25 (Standard Brazilian Gasoline), Ethanol, and CNG.

Any existing petrol vehicle can be converted to a dual-fuel petrol/CNG vehicle. Authorized shops can do the retrofitting, which involves installing a CNG cylinder, plumbing, a CNG injection system, and electronics. The cost of installing a CNG conversion kit can often reach $8,000 on passenger cars and light trucks, and is usually reserved for vehicles that travel many miles each year. CNG costs about 50% less than petrol, and emits up to 90% fewer emissions than petrol.

Locomotives
CNG locomotives are operated by several railroads. The Napa Valley Wine Train in the US successfully retrofitted a diesel locomotive to run on compressed natural gas before 2002. This converted locomotive was upgraded to utilize a computer-controlled fuel injection system in May 2008, and is now the Napa Valley Wine Train's primary locomotive. Ferrocarril Central Andino in Peru, has run a CNG locomotive on a freight line since 2005. CNG locomotives are usually diesel–electric locomotives that have been converted to use compressed natural gas generators instead of diesel generators to generate the electricity that drives the traction motors. Some CNG locomotives are able to selectively fire their cylinders only when there is a demand for power, which, theoretically, gives them a higher fuel-efficiency than conventional diesel engines. CNG is also cheaper than petrol or diesel fuel.

Natural gas transport
CNG is used to transport natural gas by sea for intermediate distances, using CNG carrier ships, especially when the infrastructure for pipelines or LNG is not in place. At short distances, undersea pipelines are often more cost-effective, and for longer distances, LNG is often more cost-effective.

Advantages

 * Natural gas vehicles have lower maintenance costs than other hydrocarbon-fuel-powered vehicles.
 * CNG fuel systems are sealed, preventing fuel losses from spills or evaporation.
 * Increased life of lubricating oils, as CNG does not contaminate and dilute the crankcase oil.
 * Being a gaseous fuel, CNG mixes easily and evenly in air.
 * CNG is less likely to ignite on hot surfaces, since it has a high auto-ignition temperature (540 °C), and a narrow range (5–15 percent) of flammability.
 * CNG-powered vehicles are considered to be safer than petrol-powered vehicles.
 * Less pollution and more efficiency:
 * CNG emits significantly less pollution directly than petrol or oil when combusted (e.g., unburned hydrocarbons (UHC), carbon monoxide (CO), nitrogen oxides (NOX), sulfur oxides (SOx) and PM (particulate matter)). For example, an engine running on petrol for 100 km produces 22 kilograms of, while covering the same distance on CNG emits only 16.3 kilograms of.
 * The lifecycle greenhouse gas emissions for CNG compressed from California's pipeline natural gas is given a value of 67.70 grams of -equivalent per megajoule (gCO2e/MJ) by CARB (the California Air Resources Board), approximately 28 percent lower than the average petrol fuel in that market (95.86 gCO2e/MJ).
 * CNG produced from landfill biogas was found by CARB to have the lowest greenhouse gas emissions of any fuel analyzed, with a value of 11.26 gCO2e/MJ (more than 88 percent lower than conventional petrol) in the low-carbon fuel standard that went into effect on January 12, 2010.
 * Due to lower carbon dioxide emissions, switching to CNG can help mitigate greenhouse gas emissions. However, natural gas leaks (both in the direct use and in the production and delivery of the fuel) represent an increase in greenhouse gas emissions. The ability of CNG to reduce greenhouse gas emissions over the entire fuel lifecycle will depend on the source of the natural gas and the fuel it is replacing.

Drawbacks
Compressed natural gas vehicles require a greater amount of space for fuel storage than conventional petrol-powered vehicles. Since it is a compressed gas, rather than a liquid like petrol, CNG takes up more space for each GGE (petrol gallon equivalent). However, the cylinders used to store the CNG take up space in the trunk of a car or bed of a pickup truck that has been modified to additionally run on CNG. This problem is solved in factory-built CNG vehicles that install the cylinders under the body of the vehicle, leaving the trunk free, e.g., Fiat Multipla, New Fiat Panda, Volkswagen Touran Ecofuel, Volkswagen Caddy Ecofuel, Chevy Taxi, which sold in countries such as Peru. Another option is installation on roof (typical on buses), but this could require structural modifications. In 2014, a test (by the Danish Technological Institute) of Euro6 heavy vehicles on CNG and diesel showed that CNG had higher fuel consumption, the same noise and production of CO2 and particulates, but NOX emission was lower.

Leakage of unburned methane as natural gas is a significant issue because methane, the primary component of natural gas, is a powerful, short-lived greenhouse gas. It is more than 100 times more potent at trapping energy than carbon dioxide, the principal contributor to man-made climate change.

Comparison with other natural gas fuels
Compressed natural gas is often confused with LNG (liquefied natural gas). Both are stored forms of natural gas. The main difference is that CNG is stored at ambient temperature and high pressure, while LNG is stored at low temperature and nearly ambient pressure. In their respective storage conditions, LNG is a liquid and CNG is a supercritical fluid. CNG has a lower cost of production and storage compared to LNG as it does not require an expensive cooling process and cryogenic tanks. However, CNG requires a much larger volume to store the energy equivalent of petrol and the use of very high pressures (3000 to 4000 psi, or 205 to 275 bar). As a consequence of this, LNG is often used for transporting natural gas over large distances, in ships, trains or pipelines, where the gas is converted into CNG before distribution to the end user.

Natural gas is being experimentally stored at lower pressure in a form known as an ANG (adsorbed natural gas) cylinder, where it is adsorbed at 35 bar (500 psi, the pressure of gas in natural gas pipelines) in various sponge-like materials, such as carbon and MOFs (metal-organic frameworks). The fuel is stored at similar or greater energy density than CNG. This means that vehicles can be refueled from the natural gas network without extra gas compression, the fuel cylinders can be slimmed down and made of lighter, weaker materials.

It is possible to mix the ANG and CNG technology to reach an increased capacity of natural gas storage. In this process known as high pressure ANG, a high pressure CNG tank is filled by absorbers such as activated carbon (which is an adsorbent with high surface area) and stores natural gas by both CNG and ANG mechanisms.

Compressed natural gas is sometimes mixed with hydrogen (HCNG), which increases the H/C ratio (hydrogen/carbon ratio) of the fuel and gives it a flame speed up to eight times higher than CNG.

Codes and standards
The lack of harmonized codes and standards across international jurisdictions is an additional barrier to NGV market penetration. The International Organization for Standardization has an active technical committee working on a standard for natural gas fuelling stations for vehicles.

Despite the lack of harmonized international codes, natural gas vehicles have an excellent global safety record. Existing international standards include ISO 14469-2:2007 which applies to CNG vehicle nozzles and receptacle and ISO 15500-9:2012 specifies tests and requirements for the pressure regulator.

The National Fire Protection Association's NFPA 52 code covers natural gas vehicle safety standards in the United States.

Worldwide adoption
Iran, Pakistan, Argentina, Brazil and China have the highest number of CNG run vehicles in the world.

Natural gas vehicles are increasingly used in Iran, Pakistan, the Asia-Pacific region, the Indian capital of Delhi, and other large cities such as Ahmedabad, Mumbai, Pune, and Kolkata, as well as cities such as Lucknow, Kanpur, Varanasi, and others.

Its use is also increasing in South America, Europe, and North America, because of rising petrol prices.

Africa
Egypt is amongst the top 10 countries in CNG adoption, with 128,754 CNG vehicles and 124 CNG fueling stations. Egypt was also the first nation in Africa and the Middle East to open a public CNG fueling station in January 1996.

The vast majority (780,000) have been produced as dual fuel-vehicles by the auto manufacturer in the last two years, and the remainder have been converted utilizing after market conversion kits in workshops. There are 750 active refueling stations country wide with an additional 660 refueling stations under construction and expected to come on stream. Currently the major problem facing the industry as a whole is the building of refueling stations that is lagging behind dual fuel vehicle production, forcing many to use petrol instead.

Nigeria CNG started with a pilot project in Benin City Edo State in 2010 by NIPCO Gas Limited. NIPCO Gas Limited is a 100% subsidiary of NIPCO PLC. As of June 2020, seven CNG stations have been built in Benin City Edo State, with about 7,500 cars running on CNG in Benin City Edo state. In Benin City Edo state, major companies such as Coca-Cola, 7up, Yongxing Steel are using CNG to power their fork-lifts/trucks while Edo City Transport Ltd (ECTS) is also running some of its buses on CNG. Kwale, Nigeria CNG stations were inaugurated by Mr. Abhishek Sharma, the head of marketing (Natural Gas) from NIPCO Gas Limited in 2019.

China
In China, companies such as Sino-Energy are active in expanding the footprint of CNG filling stations in medium-size cities across the interior of the country, where at least two natural gas pipelines are operational.

Malaysia
In Malaysia, the use of CNG was originally introduced for taxicabs and airport limousines during the late 1990s, when new taxis were launched with CNG engines while taxicab operators were encouraged to send in existing taxis for full engine conversions. The practice of using CNG remained largely confined to taxicabs predominately in the Klang Valley and Penang due to a lack of interest. No incentives were offered for those besides taxicab owners to use CNG engines, while government subsidies on petrol and diesel made conventional road vehicles cheaper to use in the eyes of the consumers. Petronas, Malaysia's state-owned oil company, also monopolises the provision of CNG to road users. As of July 2008, Petronas only operates about 150 CNG refueling stations, most of which are concentrated in the Klang Valley. At the same time, another 50 were expected by the end of 2008.

As fuel subsidies were gradually removed in Malaysia starting June 5, 2008, the subsequent 41 percent price hike on petrol and diesel fuel led to a 500 percent increase in the number of new CNG cylinders installed. National car maker Proton considered fitting its Waja, Saga and Persona models with CNG kits from Prins Autogassystemen by the end of 2008, while a local distributor of locally assembled Hyundai cars offers new models with CNG kits. Conversion centres, which also benefited from the rush for lower running costs, also perform partial conversions to existing road vehicles, allowing them to run on both petrol or diesel and CNG with a cost varying between RM3,500 to RM5,000 for passenger cars.

Myanmar
The Ministry of Transport of Myanmar passed a law in 2005 which required that all public transport vehicles – buses, trucks and taxis, be converted to run on CNG. The Government permitted several private companies to handle the conversion of existing diesel and petrol cars, and also to begin importing CNG variants of buses and taxis. Accidents and rumours of accidents, partly fueled by Myanmar's position in local hydrocarbon politics, has discouraged citizens from using CNG vehicles, although now almost every taxi and public bus in Yangon, Myanmar's largest city, run on CNG. CNG stations have been set up around Yangon and other cities, but electricity shortages mean that vehicles may have to queue up for hours to fill their gas containers. The Burmese opposition movements are against the conversion to CNG, as they accuse the companies of being proxies of the junta, and also their desire that the petrodollars earned by the regime should go towards the defense sector rather than towards improving the infrastructure or welfare of the people.

India
In India, there are over 4500 CNG Stations all over the country now as compared to 2014 when the country only had about 900 CNG Stations. The government is aiming to increase the use of CNG powered vehicles by setting up more CNG stations in the country, the aim is to increase the current number to 8000 CNG Stations in the next two years.

As of December 2022, the state of Gujarat has the highest number of CNG Pumps in the country followed by Uttar Pradesh being the second highest and with Maharashtra falling little behind the above regions.

Pakistan
In Pakistan, the Karachi government under the order of the Supreme Court in 2004 made it mandatory for all city buses and auto rickshaws to run on CNG with the intention of reducing air pollution.

In 2012, the federal government announced plans to gradually phase out CNG over a period of approximately three years given natural gas shortages which have been negatively affecting the manufacturing sector. Aside from limiting electricity generation capacity, gas shortages in Pakistan have also raised the costs of business for key industries including the fertilizer, cement and textile sectors.

Singapore
In Singapore, CNG was once used by public transport vehicles like buses and taxis, as well as goods vehicles until 2018. During its heyday in 2008 onwards, more owners of private cars had sought interest in converting their petrol-driven vehicles to also run on CNG – due to rising petrol prices. The initial cost of converting a regular vehicle to dual fuel at the German conversion workshop of C. Melchers, for example, is around S$3,800; with the promise of real cost-savings that dual-fuel vehicles bring over the long term.

Singapore currently has five operating filling stations for natural gas. Sembcorp Gas Pte Ltd. runs the station on Jurong Island and, jointly with Singapore Petroleum Company, the filling station at Jalan Buroh. Both these stations are in the western part of the country. Another station on the mainland is in Mandai Link to the north and is operated by SMART Energy. SMART also own a second station on Serangoon North Ave 5 which was set up end of March 2009; The fifth and largest station in the world, located in Toh Tuck, was opened by the UNION Group in September 2009. This station is recognized by the Guniness World Records as being the largest in the world with 46 refuelling hoses. The Union Group, which operates 1000 CNG Toyota Wish taxis then planned to introduce another three daughter stations and increase the CNG taxi fleet to 8000 units.

As a key incentive for using this eco-friendly fuel Singapore has a green vehicle rebate for users of CNG technology. First introduced in January 2001, the GVR grants a 40 percent discount on the OMV (open market value) cost of newly registered green passenger vehicles. This initiative will end at the end of 2012 as the government believes the 'critical mass' of CNG vehicles would then have been built up.

Due to reliability issues and lower ranges that CNG provided (as cited by users’ feedback), refueling stations mostly concentrated in the western end of Singapore, the rising demand of greener solutions like hybrid technologies, led to its demise where both public buses and the last CNG taxis were on its way to being scrapped in 2018.

Europe
In Italy, there are more than 1173 CNG stations. The use of methane for vehicles, started in the 1930s and has continued off and on until today. Since 2008 there have been a large market expansion for natural gas vehicles (CNG and LPG) caused by the rise of petrol prices and by the need to reduce air pollution emissions. Before 1995 the only way to have a CNG-powered car was by having it retrofitted with an after-market kit. A large producer was Landi Renzo, Tartarini Auto, Prins Autogassystemen, OMVL, BiGAs,... and AeB for electronic parts used by the most part of kit producer. Landi Renzo and Tartarini selling vehicles in Asia and South America. After 1995 bi-fuel cars (petrol/CNG) became available from several major manufacturers. Currently Fiat, Opel, Volkswagen, Citroën, Renault, Volvo and Mercedes sell various car models and small trucks that are petrol/CNG powered. Usually CNG parts used by major car manufacturers are actually produced by automotive aftermarket kit manufacturers, e.g. Fiat use Tartarini Auto components, Volkswagen use Teleflex GFI and Landi Renzo components.

In Belgium, CNG is a very new fuel. At the beginning of 2014 there were only 17 refuelling stations, all of them in Flanders, but the number is now increasing rapidly. At the beginning of 2015 there were 29 refueling stations in Belgium, all of them in Flanders. As of January 2017, there are 76 active refueling stations in Belgium, most of them being in Flanders since only 7 of them are in Wallonia or Brussels. As a fuel and compared to petrol, CNG has an advantageous fiscal treatment with lower excises duties (although VAT is always paid). Since CNG, as a car fuel, is not totally exempted of excise duties, CNG cars do not pay a prime road tax to partially compensate the State for the loss of revenue. Instead LPG cars pay a prime road tax in Belgium, because LPG is totally exempted from excise duties. Since CNG is not totally exempted of excise duties, in Belgium it is allowed to connect a car to the home network of natural gas and to refuel the car from home. The purchase of CNG cars is not subsidised by the government, but by the Belgian producers and distributors of natural gas. Fiat and Volkswagen sell factory-equipped CNG-cars in Belgium. At the end of 2018 there were 11,188 vehicles running with CNG in Belgium. In Germany, CNG-generated vehicles are expected to increase to two million units of motor-transport by 2020. The cost for CNG fuel is between 1/3 and 1/2 compared to other fossil fuels in Europe. In 2016 there are around 900 CNG stations in Germany and major German car manufacturers like Volkswagen, Mercedes, Opel, Audi offer CNG engines on most of their models. Augsburg is one of the few cities that only run CNG operated public buses since 2011.

In Turkey, Ankara municipality is increasingly using CNG buses, where numbers have reached 1090 by 2011. Istanbul has started in 2014 with an order of 110 buses. Konya also added 60 buses to its fleet the same year.

In Portugal, there are 9 CNG refueling stations as of September 25, 2017.

In Hungary, there are four public CNG refueling stations in the cities Budapest, Szeged, Pécs and Győr. The public transportation company of Szeged, Szolnok and some districts in Budapest runs buses mainly on CNG.

In Bulgaria, there are 96 CNG refueling stations as of July 2011. One can be found in most of Bulgaria's big towns. In the capital Sofia there are 22 CNG stations making it possibly the city with the most publicly available CNG stations in Europe. There are also quite a few in Plovdiv, Ruse, Stara Zagora and Veliko Tarnovo as well as in the towns on the Black Sea – Varna, Burgas, Nesebar and Kavarna. CNG vehicles are becoming more and more popular in the country. The fuel is mostly used by taxi drivers because of its much lower price compared to petrol. Currently (as of July, 2015) the city of Sofia is rapidly renewing its public transport fleet with MAN Lion's City buses running on CNG. Also, many companies switch to CNG cargo vans and even heavy trucks for their daily operations within city limits.

In North Macedonia, there is one CNG station located in the capital Skopje, but it is not for public use. Only twenty buses of the local Public Transport Company have been fitted to use a mixture of diesel and CNG. The first commercial CNG station in Skopje is in the advanced stage of development and was expected to start operation in July 2011.

In Serbia, there are about 20 public CNG refuelling stations as of August 2019. Four in the capital Belgrade, and the rest in the towns of Subotica (1), Novi Sad (1), Zrenjanin (1), Pancevo (2), Kruševac (1), Kragujevac (1), Cacak (2), and so on. Detailed list is currently available on CNGEurope Web site.

In Slovenia, there are four public CNG refuelling stations as of December 2018. Two in the capital Ljubljana, and one each in Maribor and Jesenice. Additionally, at least 14 new refuelling stations are planned in all city municipalities by the end of 2020. Ljubljana Passenger Transport operates 66 CNG fuelled city buses, as of May 2016. Its Maribor counterpart, Marprom has 19 CNG city buses in their fleet, as of October 2018.

In Croatia, there are two public CNG refuelling stations situated close to the center of Zagreb and in Rijeka. At least 60 CNG buses are in use as a form of a public transport (Zagreb public transport services).

In Estonia, there are 11 public CNG refuelling stations – four in the country's capital Tallinn, and one each in Tartu, Pärnu, Viljandi, Rakvere, Jõhvi, and Narva. From 2011 on, Tartu has five Scania-manufactured CNG buses operating its inner-city routes.

In Sweden, there are currently 90 CNG filling stations available to the public (as compared to about 10 LPG filling stations), primarily located in the southern and western parts of the country as well the Mälardalen region Another 70–80 CNG filling stations are under construction or in a late stage of planning (completions 2009–2010). Several of the planned filling stations are located in the northern parts of the country, which will greatly improve the infrastructure for CNG car users. There are approx. 14,500 CNG vehicles in Sweden (2007), of which approx. 13,500 are passenger cars and the remainder includes buses and trucks. In Stockholm, the public transportation company SL currently operates 50 CNG buses but have a capacity to operate 500. The Swedish government recently prolonged its subsidies for the development of CNG filling stations, from 2009 to 2012–31 to 2010-12-31.

In Spain, CNG is a very new fuel and the refueling network is being developed. In Madrid, the EMT, uses 1915 buses running with CNG. At the beginning of 2015 there were 35 CNG refueling stations in Spain. Several car brands sell brand-new cars running with CNG, including Fiat, Volkswagen, Seat and Skoda among others.

As of 2013, there are 47 public CNG filling stations in the Czech Republic, mainly in the big cities. Local bus manufacturers SOR Libchavy and Tedom produce CNG versions of their vehicles, with roof-mounted cylinders.

Iran
Iran has one of the largest fleets of CNG vehicles and CNG distribution networks in the world. There are 2335 CNG fueling stations, with a total of 13,534 CNG nozzles. The number of CNG burning vehicles in Iran exceeds 3.5 million. CNG consumption by Iran's transportation sector is around 20 million cubic meters per day.

Canada
Natural gas has been used as a motor fuel in Canada for over 20 years. With assistance from federal and provincial research programs, demonstration projects and NGV market deployment programs during the 1980s and 1990s, the population of light-duty NGVs grew to over 35,000 by the early 1990s. This assistance resulted in a significant adoption of natural gas transit buses as well.

The NGV market started to decline after 1995, eventually reaching today's vehicle population of about 12,000.

This figure includes 150 urban transit buses, 45 school buses, 9,450 light-duty cars and trucks, and 2,400 forklifts and ice-resurfacers. The total fuel use in all NGV markets in Canada was 1.9 PJs (petajoules) in 2007 (or 54.6 million liters of petrol liters equivalent), down from 2.6 PJs in 1997. Public CNG refueling stations have declined in quantity from 134 in 1997 to 72 today. There are 22 in British Columbia, 12 in Alberta, 10 in Saskatchewan, 27 in Ontario and two in Québec. There are only 12 private fleet stations.

Canadian industry has developed CNG-fueled truck and bus engines, CNG-fueled transit buses, and light trucks and taxis.

Fuelmaker Corporation of Toronto, the Honda-owned manufacturer of CNG auto refueling units, was forced into bankruptcy by parent Honda USA for an unspecified reason in 2009. The various assets of Fuelmaker were subsequently acquired by Fuel Systems Corporation of Santa Ana, California.

United States
Similar to Canada, the United States has implemented various NGV initiatives and programs since 1980, but has had limited success in sustaining the market. There were 105,000 NGVs in operation in 2000; this figure peaked at 121,000 in 2004, and decreased to 110,000 in 2009.

In the United States, federal tax credits are available for buying a new CNG vehicle. Use of CNG varies from state to state; only 34 states have at least one CNG fueling site.

In Texas, Railroad Commissioner David Porter launched his Texas Natural Gas Initiative in October 2013 to encourage the adoption of natural gas fuel in the transportation and exploration and production sectors. As of 2015 Texas is rapidly becoming a leader in natural gas infrastructure in the US with 137 natural gas fueling stations (private and public). Nine months into FY2015 Commissioner Porter reports Texas CNG, LNG Sales Show 78 Percent Increase Over FY 2014 year to date. Per Commissioner Porter in June 2015: "Natural gas vehicles are becoming mainstream faster than expected. These collections are nearly double the amount collected last year at this time. At 15 cents per gallon equivalent, $3,033,600 of motor fuel tax equates to the sale of 20,224,000 gallon equivalents of natural gas." The $3 million in Texas natural gas tax receipts is for both CNG and LNG for FY2015 through the May 2015. The Texas fiscal year starts Sept 1 so 9 months tax collections are represented.

In Athens, Ala., the city and its Gas Department installed a public CNG station on the Interstate 65 Corridor, making it the only public CNG station between Birmingham and Nashville as of February 2014. The city's larger fleet vehicles such as garbage trucks also use this public station for fueling. The city also has two slow-fill non-public CNG stations for its fleet. Athens has added CNG/petrol Tahoes for police and fire, a CNG Honda Civic, CNG Heil garbage trucks, and CNG/petrol Dodge pickup trucks to its fleet.

In California, CNG is used extensively in local city and county fleets, as well as public transportation (city/school buses). There are 90 public fueling stations in southern California alone, and travel from San Diego so the Bay Area to Las Vegas and Utah is routine with the advent of online station maps such as www.cngprices.com. Compressed natural gas is typically available for 30-60 percent less than the cost of petrol in much of California. The 28 buses running the Gwinnett County Transit local routes run on 100 percent CNG. Additionally, about half of the Georgia Regional Transportation Authority express fleet, which runs and refuels out of the Gwinnett County Transit facility, uses CNG.

The Massachusetts Bay Transportation Authority was running 360 CNG buses as early as in 2007, and is the largest user in the state.

The Metropolitan Transportation Authority (MTA) of New York City currently has over 900 buses powered by compressed natural gas, with CNG bus depots located in Brooklyn, The Bronx, and Queens.

The Nassau Inter-County Express (or NICE Bus, formerly New York MTA Long Island Bus) runs a 100% Orion CNG-fueled bus fleet for fixed-route service, consisting of 360 buses for service in Nassau County, parts of Queens, New York, and the western sections of Suffolk County.

The City of Harrisburg, Arkansas has switched some of the city's vehicles to compressed natural gas in an effort to save money on fuel costs. Trucks used by the city's street and water, sewer, and gas departments have been converted from petrol to CNG.

Personal use of CNG is currently a small niche market, though with current tax incentives and a growing number of public fueling stations available, it is experiencing unprecedented growth. The state of Utah offers a subsidised statewide network of CNG filling stations at a rate of $1.57/gge, while petrol is above $4.00/gal.

Elsewhere in the nation, retail prices average around $2.50/gge, with home refueling units compressing gas from residential gas lines for under $1/gge. Other than aftermarket conversions, and government used vehicle auctions, the only currently produced CNG vehicle in the United States is the Honda Civic GX sedan, which is made in limited numbers and available only in states with retail fueling outlets.

An initiative, known as Pickens Plan, calls for the expansion of the use of CNG as a standard fuel for heavy vehicles has been recently started by oilman and entrepreneur T. Boone Pickens. California voters defeated Proposition 10 in the 2008 General Election by a significant (59.8 percent to 40.2 percent) margin. Proposition 10 was a $5 billion bond measure that, among other things, would have given rebates to state residents that purchase CNG vehicles.

On February 21, 2013, T. Boone Pickens and New York Mayor, Michael Bloomberg unveiled a CNG powered mobile pizzeria. The company, Neapolitan Express uses alternative energy to run the truck as well as 100 percent recycled and compostable materials for their carryout boxes.

Congress has encouraged conversion of cars to CNG with a tax credits of up to 50 percent of the auto conversion cost and the CNG home filling station cost. However, while CNG is much cleaner fuel, the conversion requires a type certificate from the EPA. Meeting the requirements of a type certificate can cost up to $50,000. Other non-EPA approved kits are available. A complete and safe aftermarket conversion using a non-EPA approved kit can be achieved for as little as $400 without the cylinder.

Deployments
AT&T ordered 1,200 CNG-powered cargo vans from General Motors in 2012. It is the largest-ever order of CNG vehicles from General Motors to date. AT&T has announced its intention to invest up to $565 million to deploy approximately 15,000 alternative fuel vehicles over a 10-year period through 2018, will use the vans to provide and maintain communications, high-speed Internet and television services for AT&T customers.

South America
CNG vehicles are commonly used in South America, where these vehicles are mainly used as taxicabs in main cities of Argentina and Brazil. Normally, standard petrol vehicles are retrofitted in specialized shops, which involve installing the gas cylinder in the trunk and the CNG injection system and electronics. Argentina and Brazil are the two countries with the largest fleets of CNG vehicles, with a combined total fleet of more than 3.4 million vehicles by 2009. Conversion has been facilitated by a substantial price differential with liquid fuels, locally produced conversion equipment and a growing CNG-delivery infrastructure.

As of 2009 Argentina had 1,807,186 NGV's with 1,851 refueling stations across the nation, or 15 percent of all vehicles; and Brazil had 1,632,101 vehicles and 1,704 refueling stations, with a higher concentration in the cities of Rio de Janeiro and São Paulo.

Colombia had an NGV fleet of 300,000 vehicles, and 460 refueling stations, as of 2009. Bolivia has increased its fleet from 10,000 in 2003 to 121,908 units in 2009, with 128 refueling stations. Peru had 81,024 NGVs and 94 fueling stations as 2009, but that number is expected to skyrocket as Peru sits on South America's largest gas reserves. In Peru several factory-built NGVs have the cylinders installed under the body of the vehicle, leaving the trunk free. Among the models built with this feature are the Fiat Multipla, the new Fiat Panda, the Volkswagen Touran Ecofuel, the Volkswagen Caddy Ecofuel and the Chevy Taxi. Other countries with significant NGV fleets are Venezuela (15,000) and Chile (8,064) as of 2009.

Oceania
During the 1970s and 1980s, CNG was commonly used in New Zealand in the wake of the oil crises, but fell into decline after petrol prices receded. At the peak of natural gas use, 10 percent of New Zealand's cars were converted, around 110,000 vehicles.

For a period of time, Brisbane Transport in Queensland, Australia adopted a policy of purchasing only CNG buses. Brisbane Transport has 215 Scania L94UB and 324 MAN 18.310 models as well as 30 MAN NG 313 articulated CNG buses. The State Transit Authority purchased 100 Scania L113CRB, 283 Mercedes-Benz O405NH and 254 Euro 5-compliant Mercedes-Benz OC500LE buses.

In the 1990s, Benders Busways of Geelong, Victoria trialled CNG buses for the Energy Research and Development Corporation.

Martin Ferguson, Ollie Clark and Noel Childs featured on The 7:30 Report raised the issue of CNG as an overlooked transport fuel option in Australia, highlighting the large volumes of LNG currently being exported from the North West Shelf in light of the cost of importing crude oil to Australia.

title: Compressed natural gas


text:
Dream Pod 9

Dream Pod 9 (DP9), formerly Ianus Games, is a Montreal-based Canadian game publisher. Its most notable products are Heavy Gear, Jovian Chronicles, Tribe 8, and Gear Krieg, as well as the Silhouette role-playing game system.

Ianus
In 1987, Montreal-based Ianus Publications was licensed by Harmony Gold to publish Protoculture Addicts, a quarterly magazine dedicated to the Robotech TV series. In 1989, Ianus relinquished the Robotech license so that they could turn Protoculture Addicts, into a bi-monthly magazine with an industry-wide focus; it became the first large mainstream anime and manga magazine in North America. In 1991, Ianus began publishing the mecha-inspired Mecha Press.

The following year, Ianus and R. Talsorian Games (RTG) struck a deal to develop a series of products set in an alternate reality based on RTG's successful game Cyberpunk 2020. The Ianus design team working on this project became known in-house as Dream Pod 9, and within three years had produced 15 various rulebooks and adventure modules.

In 1993 the Dream Pod 9 design team then created Jovian Chronicles, a new setting for RTG's Mekton II roleplaying game. In 1993, the same design team was hired by Palladium Books to work on supplementary deck plans of the Macross II roleplaying game. The design team, under license from RTG, also created the comedy sf game Star Riders using the rules system from RTG's Teenagers from Outer Space roleplaying game. This also resulted in a three-part comic book anthology in Dark Horse Presents.

In 1994, the Dream Pod 9 team developed a card game called Heavy Gear Fighter, their first in-house project, and started to develop a game called Project A-ko: The Roleplaying Game based on the anime movie Project A-ko, as well as a roleplaying game system.

Dream Pod 9
In 1995, the Dream Pod 9 team released the first edition of Heavy Gear, their first roleplaying and combat game that used the design team's roleplaying game system called "Silhouette", and started using a "Dream Pod 9" logo to identify their work. In December 1995, after experiencing strong growth in both the magazine business and the games division, Ianus decided to split into two ventures: Protoculture, which continued to publish Protoculture Addicts; and a completely independent game publisher, Dream Pod 9, which would design and market miniatures and gaming books. Mecha (giant robots) would be the focus of Dream Pod 9.

Silhouette game system
The Silhouette game system was developed by Dream Pod 9 specifically to work with both its mecha-based miniatures combat games and roleplaying adventures. As Moby Games summarized it: "This new addition in the world of giant robots (mecha) gaming not only introduced realistic warfare game mechanics to the hobby, but gave North Americans what they have been waiting for since they were introduced to the world of mecha warfare in the early eighties: a story that is both vivid and entertaining, and designs which are made by North Americans for North Americans."

Rick Swan wrote, in Dragon #244 (1998), "I do, however, like the system, one of the smartest set of universal rules this side of the GURPS* game. Called Silhouette, the system uses 6-sided dice to generate quick and sensible results. All skills are rated from a low of 0 (little or no aptitude) to 5 (superhuman aptitude). Actions are assigned thresholds of difficulty, ranging from 1 (effortless) to 12 (near-impossible). When a PC attempts an action, the gamemaster assigns a threshold and determines the relevant skill. The player rolls a number of dice equal to the skill level. The results are not added together. Instead, the highest number rolled on an individual die is considered the outcome (if a player rolls two dice and gets a 2 and a 5, the outcome is 5). Every additional 6 adds 1 to the total (if he gets two 6s, the outcome is 7). If all of the dice show 1s, the PC suffers a critical mishap. Actions with higher thresholds, then, become increasingly difficult to achieve. PCs with low skill levels are more likely to fumble then their high-level counterparts. It’s a clever, elegant system, a snap to learn and adjudicate. Character creation is equally smooth, involving the purchase of attributes (Agility, Build, Perception) and skills (Acrobatics, Law, Stealth) from a pool of character points. Simple formulas are used to compute secondary traits (Strength, Stamina, Health). Creating a PC from scratch takes half an hour, tops".

RPGGeek wrote that "the system is based upon rolling multiple d6s and the results exaggerate the effect either way. A big success roll results in highly positive effects, a bad roll means you suffer more damage for example. There were three editions of the system, with Dream Pod 9 bringing out a Silhouette Core rules book to enable all their games to be run from one system". In 2003, Dream Pod 9 released a conversion guide from the Silhouette game system to the d20 Open Gaming License.

Heavy Gear
In 1996, Dream Pod 9 partnered with Activision to create a Heavy Gear computer game, and the following year, Heavy Gear: The New Breed became Activision's first property to sell over a million copies. At the height of Dream Pod 9's popularity in the late 1990s, despite having a staff of only nine writers, Heavy Gear was reportedly the fourth-most popular roleplaying game in the U.S.

In 1997, Dream Pod 9 released the second edition rules for Heavy Gear, again using the Silhouette game system.

In 1998, Dream Pod 9 released their next major property, Jovian Chronicles, a rewrite of the setting they had created for the Mekton II RPG in 1993, now adapted to their own Silhouette game system. The company then published the post-apocalyptic fantasy role-playing game Tribe 8 (1998), and then its fourth role-playing game Gear Krieg (2001), set in an alternate-history World War II.

In 1999, Dream Pod 9 licensed Heavy Gear to Sony Pictures, which resulted in a 40-episode 3D-animated series that had world-wide syndication. In 2002, Heavy Gear: The Animated Series was nominated for a Golden Reel Award for Best Sound Editing in Television Animation.

Decline
In 1999, Activision's Heavy Gear II: Black Talon was commercially unsuccessful, selling less than 30,000 copies by the end of the year; Activision chose not to develop a third title.

By 2001, sales of Dream Pod 9's Silhouette-based games also declined as the d20 system became popular throughout the role-playing game industry. Dream Pod 9 responded by releasing a third edition of the Heavy Gear roleplaying game in 1993 that had been converted to the d20 system under the Open Game License (OGL). Since this edition could not include game system rules under the terms of the OGL, players had to purchase the Players Handbook for the 3rd edition of Dungeons & Dragons in order to play the game. For players who still wanted to use the Silhouette rules system, Dream Pod 9 also published the Silhouette CORE Rulebook (SilCORE), which contained the Silhouette rules system; conversely, it also explained how to convert previous editions of their games that used the Silhouette system to d20 rules. Regardless of which system players wanted to use, they still had to purchase two books in order to play the third edition of Heavy Gear. Sales of both products were low, and in 2004 the company ended its role-playing game production to concentrate on their miniatures combat games.

The company then created Dream Pod Entertainment to bring the company into movies and television, including work on the 2004 film Eternal with Caroline Néron and the 2007 film 300, and used this movie industry money to help fund production of Heavy Gear Blitz!, a mecha miniatures game, which was nominated for a 2007 Origins Award in the category of "Miniatures Game or Expansion of the Year". Dream Pod 9 was nominated for two ENnie Awards, "Best Miniature Product" and "Best Electronic Book", in 2008.

In 2008, Dream Pod 9 licensed the rights to Heavy Gear to Steve Jackson Games, which wanted to create a fourth edition Heavy Gear roleplaying game based on the GURPS rule system; ultimately Steve Jackson Games decided to shelve the project, and in 2010 relinquished their rights to the game.

After that decision, when an interviewer asked Dream Pod 9 company president Robert Dubois which of the three versions of Heavy Gear players should use, he replied, "The second edition of the Heavy Gear Roleplaying Game is the best version of the RPG and has the most support in material." In the same interview, Dubois also revealed that the design team was working on a fourth edition that would be a revision of the second edition, not as a roleplaying game but as a combat game compatible with the miniatures game Heavy Gear Blitz!; to date, it has not been published.

In 2012, Dream Pod 9 announced a five-year partnership with Stompy Bot Productions (now BlocPlay Entertainment) to commercialize Heavy Gear; in 2017, the two companies renewed the partnership for a further five years, with plans to include sponsorship of eSports tournamaents.

In 2013, Dream Pod 9 was nominated for an Origins Award in the category of "Best Miniatures Rules" for ''Heavy Gear Blitz! Perfect Storm: The NuCoal Field Guide''.

In 2015, ''Heavy Gear Blitz! Tabletop Wargaming - Living Rulebook'' was released for free on DrivethruRPG as a PDF. In the following year, ''Heavy Gear Blitz! Tabletop Wargaming - Quick Start Rulebook'' was also released on DrivethruRPG. Both of these rulebooks were last updated on February 23, 2018.

In 2016, Beta Playtest Rules for a new edition of Jovian Chronicles, called Jovian Wars, were released for free on DrivethruRPG as a PDF. These rules were last updated on February 14, 2018.

Kickstarter
Between 2014 and 2018, Dream Pod 9 launched six Kickstarter campaigns - five campaigns were successfully funded. All of the campaigns focused on raising funds to create new miniatures for either Heavy Gear or Jovian Wars.

Properties
The company is best known for a set of universes on which role-playing games, wargames, scale models and miniatures have been based:
 * Heavy Gear is a military science-fiction universe where human worlds wage war against one another with mecha.
 * Jovian Chronicles follows the exploration of the Solar System in the 23rd century and the conflicts that arise between the Earth and the space colonies.
 * Tribe 8 is a tribal, post-apocalyptic fantasy game of horror and epic adventures.
 * Gear Krieg takes place in an alternate reality World War II firmly set in the pulp genre.

A few other less well-known settings for use in various publications include CORE Command, a space opera universe set millennia in the future.

Reviews
In the February 1998 edition of Dragon (Issue 244), Rick Swan reviewed two of Dream Pod 9's game settings, Heavy Gear and Jovian Chronicles. Swan praised the high production values of both settings, saying, "Both are beautiful games, into which a lot of effort has been invested". He also thought the Silhouette game system rules used in both was "a clever, elegant system, a snap to learn and adjudicate" and "the smartest set of universal rules this side of the GURPS game." But overall he found Dream Pod 9's work "lifeless" and focussed more on giant robots than roleplaying, saying their work "aims more at players interested in hardware than human beings."

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Dream Pod 9


text:
William Trousdale

William Trousdale (September 23, 1790 – March 27, 1872) was an American soldier and politician. He served as the 13th governor of Tennessee from 1849 to 1851, and was United States Minister to Brazil from 1853 to 1857. He fought under Andrew Jackson in the Creek War, the War of 1812 and the Second Seminole War, and commanded the U.S. Fourteenth Infantry in the Mexican–American War. His military exploits earned him the nickname, "War Horse of Sumner County."

Early life
Trousdale was born in Orange County, North Carolina, the son of James and Elizabeth (Dobbins) Trousdale. His father was of Scots-Irish descent, and had served in the Continental Army during the American Revolution. Captain James Trousdale was given a land grant as payment for services in the Revolution, and used this grant to acquire several hundred acres in Sumner County, Tennessee. The family moved to this plot in 1796. In 1801, the family donated part of their land for the establishment of a new county seat for Sumner County, which was named Gallatin. Trousdale attended public schools and studied under a tutor, the Reverend Gideon Blackburn.

Military service and early political endeavors
Trousdale joined Captain William Edwards's Mounted Riflemen in 1812. When this company was called into service during the Creek War the following year, Trousdale was elected Lieutenant. The company saw action at the Battle of Tallushatchee and the Battle of Talladega before returning home.

In the Summer of 1814, after Trousdale had been at home for just a few months, he joined a militia company formed by Lieutenant-Colonel George Elliott. This company joined Jackson's invasion of Florida later that year. At the Battle of Pensacola in November 1814, Trousdale took part in a charge that captured several cannons on the first day of fighting. He volunteered to be among the first wave of soldiers to assault Fort San Miguel, but the fort surrendered before the assault took place.

Following the capture of Pensacola, Trousdale's unit hurried westward with Jackson's forces to defend New Orleans from an impending British invasion. They arrived in the city in December 1814, and Trousdale took part in a series of firefights and night skirmishes against the British on December 23, December 27, and January 1. He fought in the decisive Battle of New Orleans on January 8, 1815.

After the war, Trousdale returned home and studied law. He was admitted to the bar in 1820, and commenced practice in Sumner County. He ran unsuccessfully for Congress in 1827 and 1829, and served on Gallatin's Board of Aldermen from 1831 to 1835. He was elected to the Tennessee Senate in 1835, and served until the following year.

At the outbreak of the Second Seminole War in 1836, Trousdale formed his own company, and was elected colonel of the Second Regiment, First Brigade. His regiment took part in several skirmishes, and helped defeat Seminole forces at the Battle of Wahoo Swamp in November 1836.

In 1837, Trousdale once again ran for Congress for the 6th District congressional seat, but lost to William B. Campbell, his former subordinate in the Seminole War and his future gubernatorial opponent. He ran again in 1839 and 1845, but being a Democrat in a primarily Whig district, he was never successful. Trousdale campaigned for the unsuccessful Democratic presidential candidate, Martin Van Buren, in 1840.

During the Mexican–American War, Trousdale joined the Army with the rank of Colonel, and commanded the 14th U.S. Infantry. This regiment landed at Veracruz on June 13, 1847, and was placed under General Gideon Pillow's 3rd Division. Trousdale's forces linked up with Winfield Scott's forces on July 8, and began the march inland to Mexico City. Trousdale took part in the Battle of Contreras and the Battle of Churubusco on August 20, and was grazed in the shoulder while fighting in the Battle of Molino del Rey on September 8. Trousdale commanded two regiments (the 14th and 11th) and an artillery battery at the Battle of Chapultepec on September 13. During this battle, his right arm was shattered by enemy fire, though he continued fighting, and managed to lead a charge that captured an enemy cannon. For his actions at Chapultepec, Trousdale was brevetted to brigadier general by President James K. Polk on August 23, 1848.

Governor and later political endeavors
In 1849, Trousdale received the Democratic nomination for governor. His Whig opponent, Neill S. Brown, had been opposed to the Mexican–American War, and was struggling with divisions over the issue of slavery in the national Whig Party. Trousdale, on the other hand, was riding a wave of popularity for his service in the war. As a result, Trousdale edged Brown by 1,400 votes in the general election.

In Trousdale's reelection campaign in 1851, his opponent was William B. Campbell, a fellow Mexican–American War hero who had served under Trousdale in the Second Seminole War, and had defeated Trousdale for the 6th District congressional seat in 1837 and 1839. Like Brown in 1849, Trousdale's campaign was damaged by the actions of his own party. At the Nashville Convention in 1850, which Trousdale had endorsed, southern Democrats called for secession should the United States implement the Wilmot Proviso, banning slavery in territory acquired as a result of the Mexican–American War. Secession was unpopular in Tennessee at the time, and following a relatively dignified campaign, Campbell defeated Trousdale by 1,500 votes.

In 1853, Trousdale was appointed "Envoy Extraordinary and Minister Plenipotentiary" to Brazil by President Franklin Pierce. He arrived in Rio de Janeiro in July 1853, and served until 1857. He spent much of his term advocating the opening of the Amazon River to international commerce.

After returning to Sumner County, Trousdale spent the remainder of his life practicing law. He was consistently stricken with rheumatism, creating physical difficulties that prevented him from taking part in public life, as well as from serving in the Civil War in the 1860s. He nevertheless supported the Confederacy, and refused to take the Oath of Allegiance to the United States, even when Union soldiers occupied his home.

Family
Trousdale was married to Mary Ann Bugg in 1827. The couple had seven children.

Death
Trousdale died on March 27, 1872, and is interred at Gallatin City Cemetery in Gallatin, Tennessee.

Legacy
Trousdale County, Tennessee is named in his honor. His family home, the Federal-style "Trousdale Place" located near the town square of Gallatin, has been a preserved historical site since 1900.

title: William Trousdale


text:
Liquid breathing

Liquid breathing is a form of respiration in which a normally air-breathing organism breathes an oxygen-rich liquid (such as a perfluorocarbon), rather than breathing air, by selecting a liquid that can hold a large amount of oxygen and is capable of CO2 gas exchange.

This requires certain physical properties such as respiratory gas solubility, density, viscosity, vapor pressure, and lipid solubility which some perfluorochemicals (PFCs) have. Thus, it is critical to choose the appropriate PFC for a specific biomedical application, such as liquid ventilation, drug delivery or blood substitutes. The physical properties of PFC liquids vary substantially; however, the one common property is their high solubility for respiratory gases. In fact, these liquids carry more oxygen and carbon dioxide than blood.

In theory, liquid breathing could assist in the treatment of patients with severe pulmonary or cardiac trauma, especially in pediatric cases. Liquid breathing has also been proposed for use in deep diving and space travel. Despite some recent advances in liquid ventilation, a standard mode of application has not yet been established.

Approaches
Because liquid breathing is still a highly experimental technique, there are several proposed approaches.

Total liquid ventilation
Although total liquid ventilation (TLV) with completely liquid-filled lungs can be beneficial, the complex liquid-filled tube system required is a disadvantage compared to gas ventilation—the system must incorporate a membrane oxygenator, heater, and pumps to deliver to, and remove from the lungs tidal volume aliquots of conditioned perfluorocarbon (PFC). One research group led by Thomas H. Shaffer has maintained that with the use of microprocessors and new technology, it is possible to maintain better control of respiratory variables such as liquid functional residual capacity and tidal volume during TLV than with gas ventilation. Consequently, the total liquid ventilation necessitates a dedicated liquid ventilator similar to a medical ventilator except that it uses a breathable liquid. Many prototypes are used for animal experimentation, but experts recommend continued development of a liquid ventilator toward clinical applications. Specific preclinical liquid ventilator (Inolivent) is currently under joint development in Canada and France. The main application of this liquid ventilator is the ultra-fast induction of therapeutic hypothermia after cardiac arrest. This has been demonstrated to be more protective than slower cooling method after experimental cardiac arrest.

Partial liquid ventilation
In contrast, partial liquid ventilation (PLV) is a technique in which a PFC is instilled into the lung to a volume approximating functional residual capacity (approximately 40% of total lung capacity). Conventional mechanical ventilation delivers tidal volume breaths on top of it. This mode of liquid ventilation currently seems technologically more feasible than total liquid ventilation, because PLV could utilise technology currently in place in many neonatal intensive-care units (NICU) worldwide.

The influence of PLV on oxygenation, carbon dioxide removal and lung mechanics has been investigated in several animal studies using different models of lung injury. Clinical applications of PLV have been reported in patients with acute respiratory distress syndrome (ARDS), meconium aspiration syndrome, congenital diaphragmatic hernia and respiratory distress syndrome (RDS) of neonates. In order to correctly and effectively conduct PLV, it is essential to If PFC liquid is not maintained in the lung, PLV can not effectively protect the lung from biophysical forces associated with the gas ventilator.
 * 1) properly dose a patient to a specific lung volume (10–15 ml/kg) to recruit alveolar volume
 * 2) redose the lung with PFC liquid (1–2 ml/kg/h) to oppose PFC evaporation from the lung.

New application modes for PFC have been developed.

Partial liquid ventilation (PLV) involves filling the lungs with a liquid. This liquid is a perfluorocarbon such as perflubron (brand name Liquivent). The liquid has some unique properties. It has a very low surface tension, similar to the surfactant substances produced in the lungs to prevent the alveoli from collapsing and sticking together during exhalation. It also has a high density, oxygen readily diffuses through it, and it may have some anti-inflammatory properties. In PLV, the lungs are filled with the liquid, the patient is then ventilated with a conventional ventilator using a protective lung ventilation strategy. The hope is that the liquid will help the transport of oxygen to parts of the lung that are flooded and filled with debris, help remove this debris and open up more alveoli improving lung function. The study of PLV involves comparison to protocolized ventilator strategy designed to minimize lung damage.

PFC vapor
Vaporization of perfluorohexane with two anesthetic vaporizers calibrated for perfluorohexane has been shown to improve gas exchange in oleic acid-induced lung injury in sheep.

Predominantly PFCs with high vapor pressure are suitable for vaporization.

Aerosol-PFC
With aerosolized perfluorooctane, significant improvement of oxygenation and pulmonary mechanics was shown in adult sheep with oleic acid-induced lung injury.

In surfactant-depleted piglets, persistent improvement of gas exchange and lung mechanics was demonstrated with Aerosol-PFC. The aerosol device is of decisive importance for the efficacy of PFC aerosolization, as aerosolization of PF5080 (a less purified FC77) has been shown to be ineffective using a different aerosol device in surfactant-depleted rabbits. Partial liquid ventilation and Aerosol-PFC reduced pulmonary inflammatory response.

Medical treatment
The most promising area for the use of liquid ventilation is in the field of pediatric medicine. The first medical use of liquid breathing was treatment of premature babies   and adults with acute respiratory distress syndrome (ARDS) in the 1990s. Liquid breathing was used in clinical trials after the development by Alliance Pharmaceuticals of the fluorochemical perfluorooctyl bromide, or perflubron for short. Current methods of positive-pressure ventilation can contribute to the development of lung disease in pre-term neonates, leading to diseases such as bronchopulmonary dysplasia. Liquid ventilation removes many of the high pressure gradients responsible for this damage. Furthermore, perfluorocarbons have been demonstrated to reduce lung inflammation, improve ventilation-perfusion mismatch and to provide a novel route for the pulmonary administration of drugs.

In order to explore drug delivery techniques that would be useful for both partial and total liquid ventilation, more recent studies have focused on PFC drug delivery using a nanocrystal suspension. The first image is a computer model of a PFC liquid (perflubron) combined with gentamicin molecules.

The second image shows experimental results comparing both plasma and tissue levels of gentamicin after an intratracheal (IT) and intravenous (IV) dose of 5 mg/kg in a newborn lamb during gas ventilation. Note that the plasma levels of the IV dose greatly exceed the levels of the IT dose over the 4 hour study period; whereas, the lung tissue levels of gentamicin when delivered by an intratracheal (IT) suspension, uniformly exceed the intravenous (IV) delivery approach after 4 hours. Thus, the IT approach allows more effective delivery of the drug to the target organ while maintaining a safer level systemically. Both images represent the in-vivo time course over 4 hours. Numerous studies have now demonstrated the effectiveness of PFC liquids as a delivery vehicle to the lungs.

Clinical trials with premature infants and adults have been conducted. Since the safety of the procedure and the effectiveness were apparent from an early stage, the US Food and Drug Administration (FDA) gave the product "fast track" status (meaning an accelerated review of the product, designed to get it to the public as quickly as is safely possible) due to its life-saving potential. Clinical trials showed that using perflubron with ordinary ventilators improved outcomes as much as using high frequency oscillating ventilation (HFOV). But because perflubron was not better than HFOV, the FDA did not approve perflubron, and Alliance is no longer pursuing the partial liquid ventilation application. Whether perflubron would improve outcomes when used with HFOV or has fewer long-term consequences than HFOV remains an open question.

In 1996 Mike Darwin and Steven B. Harris proposed using cold liquid ventilation with perfluorocarbon to quickly lower the body temperature of victims of cardiac arrest and other brain trauma to allow the brain to better recover. The technology came to be called gas/liquid ventilation (GLV), and was shown able to achieve a cooling rate of 0.5 °C per minute in large animals. It has not yet been tried in humans.

Most recently, hypothermic brain protection has been associated with rapid brain cooling. In this regard, a new therapeutic approach is the use of intranasal perfluorochemical spray for preferential brain cooling. The nasopharyngeal (NP) approach is unique for brain cooling due to anatomic proximity to the cerebral circulation and arteries. Based on preclinical studies in adult sheep, it was shown that independent of region, brain cooling was faster during NP-perfluorochemical versus conventional whole body cooling with cooling blankets. To date, there have been four human studies including a completed randomized intra-arrest study (200 patients). Results clearly demonstrated that prehospital intra-arrest transnasal cooling is safe, feasible and is associated with an improvement in cooling time.

Diving
Gas pressure increases with depth, rising 1 bar (14.5 psi) every 10 meters to over 1,000 bar at the bottom of the Mariana Trench. Diving becomes more dangerous as depth increases, and deep diving presents many hazards. All surface-breathing animals are subject to decompression sickness, including aquatic mammals and free-diving humans. Breathing at depth can cause nitrogen narcosis and oxygen toxicity. Holding the breath while ascending after breathing at depth can cause air embolisms, burst lung, and collapsed lung.

Special breathing gas mixes such as trimix or heliox reduce the risk of nitrogen narcosis but do not eliminate it. Heliox further eliminates the risk of nitrogen narcosis but introduces the risk of helium tremors below about 500 ft. Atmospheric diving suits maintain body and breathing pressure at 1 bar, eliminating most of the hazards of descending, ascending, and breathing at depth. However, the rigid suits are bulky, clumsy, and very expensive.

Liquid breathing offers a third option, promising the mobility available with flexible dive suits and the reduced risks of rigid suits. With liquid in the lungs, the pressure within the diver's lungs could accommodate changes in the pressure of the surrounding water without the huge partial pressure gas exposures required when the lungs are filled with gas. Liquid breathing would not result in the saturation of body tissues with high pressure nitrogen or helium that occurs with the use of non-liquids, thus would reduce or remove the need for slow decompression.

A significant problem, however, arises from the high viscosity of the liquid and the corresponding reduction in its ability to remove CO2. All uses of liquid breathing for diving must involve total liquid ventilation (see above). Total liquid ventilation, however, has difficulty moving enough liquid to carry away CO2, because no matter how great the total pressure is, the amount of partial CO2 gas pressure available to dissolve CO2 into the breathing liquid can never be much more than the pressure at which CO2 exists in the blood (about 40 mm of mercury (Torr)).

At these pressures, most fluorocarbon liquids require about 70 mL/kg minute-ventilation volumes of liquid (about 5 L/min for a 70 kg adult) to remove enough CO2 for normal resting metabolism. This is a great deal of fluid to move, particularly as liquids are more viscous and denser than gases, (for example water is about 850 times the density of air ). Any increase in the diver's metabolic activity also increases CO2 production and the breathing rate, which is already at the limits of realistic flow rates in liquid breathing. It seems unlikely that a person would move 10 liters/min of fluorocarbon liquid without assistance from a mechanical ventilator, so "free breathing" may be unlikely. However, it has been suggested that a liquid breathing system could be combined with a CO2 scrubber connected to the diver's blood supply; a US patent has been filed for such a method.

Space travel
Liquid immersion provides a way to reduce the physical stress of G forces. Forces applied to fluids are distributed as omnidirectional pressures. Because liquids cannot be practically compressed, they do not change density under high acceleration such as performed in aerial maneuvers or space travel. A person immersed in liquid of the same density as tissue has acceleration forces distributed around the body, rather than applied at a single point such as a seat or harness straps. This principle is used in a new type of G-suit called the Libelle G-suit, which allows aircraft pilots to remain conscious and functioning at more than 10g acceleration by surrounding them with water in a rigid suit.

Acceleration protection by liquid immersion is limited by the differential density of body tissues and immersion fluid, limiting the utility of this method to about 15g to 20g. Extending acceleration protection beyond 20g requires filling the lungs with fluid of density similar to water. An astronaut totally immersed in liquid, with liquid inside all body cavities, will feel little effect from extreme G forces because the forces on a liquid are distributed equally, and in all directions simultaneously. Effects will still be felt because of density differences between different body tissues, so an upper acceleration limit still exists. However, it can likely be higher than hundreds of G.

Liquid breathing for acceleration protection may never be practical because of the difficulty of finding a suitable breathing medium of similar density to water that is compatible with lung tissue. Perfluorocarbon fluids are twice as dense as water, hence unsuitable for this application.

Literary works

 * Alexander Beliaev's 1928 science fiction novel Amphibian Man is based on a scientist and a maverick surgeon, who makes his son, Ichthyander (etymology: "fish" + "man") a life-saving transplant – a set of shark gills. There is a film based on the novel.
 * L. Sprague de Camp's 1938 short story "The Merman" hinges on an experimental process to make lungs function as gills, thus allowing a human being to "breathe" under water.
 * Hal Clement's 1973 novel Ocean on Top portrays a small underwater civilization living in a 'bubble' of oxygenated fluid denser than seawater.
 * Joe Haldeman's 1975 novel The Forever War describes liquid immersion and breathing in great detail as a key technology to allow space travel and combat with acceleration up to 50 G.
 * In the Star Trek: The Next Generation novel The Children of Hamlin (1988) the crew of the Enterprise-D encounter an alien race whose ships contain a breathable liquid environment.
 * Peter Benchley's 1994 novel White Shark centers around a Nazi scientist's experimental attempts to create an amphibious human, whose lungs are surgically modified to breathe underwater, and trained to reflexively do so after being flooded with a fluorocarbon solution.
 * Judith and Garfield Reeves-Stevens' 1994 Star Trek novel Federation explains that before the invention of the inertial dampener, the stresses of high-G acceleration required starship pilots to be immersed in liquid-filled capsules, breathing an oxygen-rich saline solution to prevent their lungs from being crushed.
 * Nicola Griffith's novel Slow River (1995) features a sex scene occurring within a twenty cubic foot silvery pink perflurocarbon pool, with the sensation described as "like breathing a fist".
 * Ben Bova's novel Jupiter (2000) features a craft in which the crew are suspended in a breathable liquid that allows them to survive in the high-pressure environment of Jupiter's atmosphere.
 * In Scott Westerfeld's sci-fi novel The Risen Empire (2003), the lungs of soldiers performing insertion from orbit are filled with an oxygen-rich polymer gel with embedded pseudo-alveoli and a rudimentary artificial intelligence.
 * The novel Mechanicum (2008) by Graham McNeill, Book 9 in the Horus Heresy book series, describes physically crippled (gigantic war machine) pilots encased in nutrient fluid tanks. This allows them to continue operating beyond the limits normally imposed by the body.
 * In Liu Cixin's novel The Dark Forest (2008), the warships of humanity in the 23rd century flood their compartments with an oxygen-rich liquid called 'deep-sea acceleration fluid' to protect the crew against the forces of extreme acceleration that the ships undergo. Ships enter a 'deep-sea state' where the crew are immersed in the fluid and sedated before acceleration can commence.
 * In the 2009 novel The Lost Symbol by Dan Brown, Robert Langdon (the protagonist) is completely submerged in breathable liquid mixed with hallucinogenic chemicals and sedatives as a torture and interrogation technique by Mal'akh (the antagonist). He goes through a near death experience when he inhales the liquid and blacks out, losing control over his body, but is soon revived.
 * In Greg van Eekhout's 2014 novel California Bones, two characters are put into tanks filled with liquid: "They were given no breathing apparatus, but the water in the tank was rich with perfluorocarbon, which carried more oxygen than blood."
 * In author A.L. Mengel's science fiction novel The Wandering Star (2016), several characters breathe oxygenated fluid during a dive to explore an underwater city. They submerge in high pressure "bubbles" filled with the perfluorocarbon fluid.
 * In Tiamat's Wrath, a 2019 novel in The Expanse series by James S. A. Corey, The Laconian empire utilizes a ship with full-immersion liquid-breathing pods that allow the crew to undergo significantly increased g-forces. As powerful and fuel-efficient fusion engines in the series have made the only practical limitations of a ships' acceleration the survivability of the crew, this makes the ship the fastest in all of human-colonized space.

Films and television

 * The aliens in the Gerry Anderson UFO series (1970-1971) use liquid-breathing spacesuits.
 * The 1989 film The Abyss by James Cameron features a character using liquid breathing to dive thousands of feet without compressing. The Abyss also features a scene with a rat submerged in and breathing fluorocarbon liquid, filmed in real life.
 * In the 1995 anime Neon Genesis Evangelion, the cockpits of the titular mecha are filled with a fictional oxygenated liquid called LCL which is required for the pilot to mentally sync with an Evangelion, as well as providing direct oxygenation of their blood, and dampening the impacts from battle. Once the cockpit is flooded the LCL is ionized, bringing its density, opacity, and viscosity close to that of air. Protagonist Shinji Ikari notices that LCL smells like blood. It is eventually revealed that LCL is the blood of the Evangelions' progenitor, Lilith.
 * In the movie Mission to Mars (2000), a character is depicted as being immersed in apparent breathable fluid before a high-acceleration launch.
 * In season 1, episode 13 of Seven Days (1998-2001) chrononaut Frank Parker is seen breathing a hyper-oxygenated perfluorocarbon liquid that is pumped through a sealed full body suit that he is wearing. This suit and liquid combination allow him to board a Russian submarine through open ocean at a depth of almost 1000 feet. Upon boarding the submarine he removes his helmet, expels the liquid from his lungs and is able to breathe air again.
 * In an episode of the Adult Swim cartoon series Metalocalypse (2006-2013), the other members of the band submerge guitarist Toki in a "liquid oxygen isolation chamber" while recording an album in the Mariana Trench.
 * In a Series 11 episode of Dalziel and Pascoe (1996-2007) entitled Demons on Our Shoulders, magician Lee Knight, played by Richard E Grant, performs an underwater trick using breathable fluid.
 * In an episode of the Syfy Channel show Eureka (2006-2012), Sheriff Jack Carter is submerged in a tank of "oxygen rich plasma" to be cured of the effects of a scientific accident.
 * In the anime series Aldnoah.Zero (2014-2015), episode 5 shows that Slaine Troyard was in a liquid-filled capsule when he crashed. Princess Asseylum witnessed the crash, helped him to get out of the capsule, then used CPR on him to draw out the liquid from his lungs.
 * In the 2024 anime Bang Brave Bang Bravern, the titular mecha Bravern fills its cockpit with liquid during underwater combat, telling pilot Ao Isami that it will supply oxygen directly to him while also counteracting the pressure. Bravern directly compares this to the scene from The Abyss, prompting Ao to ask how Bravern knows about the film.

Video games

 * In the classic 1995 PC turn-based strategy game X-COM: Terror from the Deep, "Aquanauts" fighting in deep ocean conditions breathe a dense oxygen-carrying fluid.
 * In the EVE Online Universe (2003), pilots in capsules (escape pods that function as the control center for the spacecraft) breathe an oxygen rich, nano-saturated, breathable glucose-based suspension solution.
 * In the game Helldivers 2 (2024), jet pilots use breathable perfluorocarbons in the cockpit to absorb G-forces and allow more dangerous maneuvers.

title: Liquid breathing


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User talk:Litegrann

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title: User talk:Litegrann


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Alfred Neubauer

Alfred Neubauer (29 March 1891 in Neutitschein – 22 August 1980 in Stuttgart) was the racing manager of the Mercedes-Benz Grand Prix team from 1926 to 1955.

Biography
Neubauer's father, Karl Neubauer, was a furniture-maker in Neutitschein (Nový Jičín), which then was part of the Austro-Hungarian Empire. Karl christened his only son Alfred, but the child quickly became known to family and friends as Friedl.

Neubauer used to repair motor vehicles while he was an officer during his service in the Imperial Austrian army. After the First World War, he joined the Austrian car manufacturer Austro-Daimler, where Ferdinand Porsche appointed him to be chief tester. From 1922 onwards, Neubauer also drove in races, although without any great success. In 1923, when Ferdinand Porsche moved to the Daimler Works at Stuttgart (Daimler-Benz was not founded until 1926), he took Neubauer with him. In 1926, recognizing that he himself was not a great racing driver, Neubauer got an inspiration that let him create the position of racing team manager (Rennleiter).

Racing drivers in those days being isolated from the outside, they often did not know their position in a race. Occasionally a driver would learn that he had won after a race merely by surprise. To overcome this situation, Alfred Neubauer devised a well thought-out system, with flags and boards, to give his drivers more tactical information. When he tried out the system for the first time at the 1926 Solituderennen on 12 September 1926, the chief steward demanded angrily that he leave the track, since his 'antics' were irritating the drivers. To Neubauer's explanation that he was the Rennleiter, the organizer responded: ‘Are you mad? I’m the Rennleiter’ (Rennleiter can also mean “race director”).

The Mercedes-Benz team was soon winning races with SS and SSK racing cars, frequently in the hands of Rudolf Caracciola, the best driver during those days. Neubauer's contribution lay not just in his tactical skill, but also in the perfectionistical, almost military drill of the pit crew, which constantly gave the team a time advantage over its rivals.

Neubauer's organization at the Mille Miglia in 1931 was a master stroke. To reach each staging post before Caracciola arrived, he repeatedly criss-crossed Italy with his team.

According to Neubauer, the origin of the Silver Arrows phrase was due to the cars being overweighted at their first race. Neubauer's story states that the rules prescribed a weight limit of 750 kg, whilst one day before the new cars' first race they weighed in at 751 kg. This led to Neubauer and Manfred von Brauchitsch eventually coming up with the idea of removing the cars' white paint. The silver-coloured aluminium bodywork was exposed, and the Silver Arrows were born. However, this story is a fabrication by Neubauer himself, a well-known raconteur. The debut race was run to Formula Libre rules, meaning there was no weight limit. Additionally, there are no reports or photographs from the time suggesting that the cars were ever run in white paint.

Silver Arrows
The Silver Arrows years were dominated by German racing cars and the rivalry between Mercedes-Benz and Auto Union. In its most successful phase, the Mercedes-Benz team's regular drivers were Rudolf Caracciola, Hermann Lang, Manfred von Brauchitsch, and Richard Seaman.

After the Second World War, Mercedes-Benz was anxious to return to racing as soon as possible, but a new formula was announced for 1954, and there was insufficient time to produce a new model. As a compromise solution, the design of the Mercedes-Benz 300 was adapted. This resulted in a new racing car, the Mercedes-Benz 300SL.

With this car, Neubauer achieved victories at the Carrera Panamericana and the Le Mans 24-hour race. When Mercedes-Benz cars returned to Grand Prix racing in 1954, the new Silver Arrows proved to be as superior as those produced before the war. Juan Manuel Fangio was World Champion in 1954 and 1955.

Probably Neubauer's worst day as racing manager was at Le Mans in 1955, when a Mercedes-Benz 300 SLR driven by Frenchman Pierre Levegh, was catapulted into the crowd, killing more than 80 people including Levegh. After consultation with Stuttgart, Neubauer withdrew the remaining cars from the event.

After the shock of Le Mans, Mercedes-Benz withdrew from racing altogether, and Alfred Neubauer retired.

title: Alfred Neubauer


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Reductive Lie algebra

In mathematics, a Lie algebra is reductive if its adjoint representation is completely reducible, hence the name. More concretely, a Lie algebra is reductive if it is a direct sum of a semisimple Lie algebra and an abelian Lie algebra: $$\mathfrak{g} = \mathfrak{s} \oplus \mathfrak{a};$$ there are alternative characterizations, given below.

Examples
The most basic example is the Lie algebra $$\mathfrak{gl}_n$$ of $$n \times n$$ matrices with the commutator as Lie bracket, or more abstractly as the endomorphism algebra of an n-dimensional vector space, $$\mathfrak{gl}(V).$$ This is the Lie algebra of the general linear group GL(n), and is reductive as it decomposes as $$\mathfrak{gl}_n = \mathfrak{sl}_n \oplus \mathfrak{k},$$ corresponding to traceless matrices and scalar matrices.

Any semisimple Lie algebra or abelian Lie algebra is a fortiori reductive.

Over the real numbers, compact Lie algebras are reductive.

Definitions
A Lie algebra $$\mathfrak{g}$$ over a field of characteristic 0 is called reductive if any of the following equivalent conditions are satisfied: Some of these equivalences are easily seen. For example, the center and radical of $$\mathfrak{s} \oplus \mathfrak{a}$$ is $$\mathfrak{a},$$ while if the radical equals the center the Levi decomposition yields a decomposition $$\mathfrak{g} = \mathfrak{s}_0 \oplus \mathfrak{z}(\mathfrak{g}).$$ Further, simple Lie algebras and the trivial 1-dimensional Lie algebra $$\mathfrak{k}$$ are prime ideals.
 * 1) The adjoint representation (the action by bracketing) of $$\mathfrak{g}$$ is completely reducible (a direct sum of irreducible representations).
 * 2) $$\mathfrak{g}$$ admits a faithful, completely reducible, finite-dimensional representation.
 * 3) The radical of $$\mathfrak{g}$$ equals the center: $$\mathfrak{r}(\mathfrak{g}) = \mathfrak{z}(\mathfrak{g}).$$
 * The radical always contains the center, but need not equal it.
 * 1) $$\mathfrak{g}$$ is the direct sum of a semisimple ideal $$\mathfrak{s}_0$$ and its center $$\mathfrak{z}(\mathfrak{g}): $$ $$\mathfrak{g} = \mathfrak{s}_0 \oplus \mathfrak{z}(\mathfrak{g}).$$
 * Compare to the Levi decomposition, which decomposes a Lie algebra as its radical (which is solvable, not abelian in general) and a Levi subalgebra (which is semisimple).
 * 1) $$\mathfrak{g}$$ is a direct sum of a semisimple Lie algebra $$\mathfrak{s}$$ and an abelian Lie algebra $$\mathfrak{a}$$: $$\mathfrak{g} = \mathfrak{s} \oplus \mathfrak{a}.$$
 * 2) $$\mathfrak{g}$$ is a direct sum of prime ideals: $$\mathfrak{g} = \textstyle{\sum \mathfrak{g}_i}.$$

Properties
Reductive Lie algebras are a generalization of semisimple Lie algebras, and share many properties with them: many properties of semisimple Lie algebras depend only on the fact that they are reductive. Notably, the unitarian trick of Hermann Weyl works for reductive Lie algebras.

The associated reductive Lie groups are of significant interest: the Langlands program is based on the premise that what is done for one reductive Lie group should be done for all.

The intersection of reductive Lie algebras and solvable Lie algebras is exactly abelian Lie algebras (contrast with the intersection of semisimple and solvable Lie algebras being trivial).

title: Reductive Lie algebra


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User talk:Darkness Productions

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224 E. Broadway
In regards to your Wikipedia talk:WikiProject Louisville query "I'm looking for information pertaining to the 224 E. Broadway building (currently inhabited by Norton Hospital). It's been rumored that it was a hotel, with an orchestra pit in the back, but I'm unsure."
 * The building you are referring to was built by the Kosair Temple in 1924 as the Kosair Hotel. In 1928 it was renamed the Fort Nelson Hotel after being sold. In 1934 it ceased being a hotel and became the US Farm Credit Association Building and (as you stated) is now medical offices. Unfortunately, I am unsure about the orchestra pit.
 * I hope this helps. Chris24 04:37, 30 September 2006 (UTC)

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Quixotic plea
You are invited to join the discussion at Wikipedia talk:Wikipediholism test. Thanks. —  04:51, 23 May 2015 (UTC)

JavaScript RegExp problem
I noticed you have experience in JavaScript. I'm hoping you can help me with a problem I've run into writing a userscript.

Please see my post at Wikipedia talk:WikiProject JavaScript.

Thank you. The Transhumanist 12:12, 5 May 2017 (UTC)

title: User talk:Darkness Productions


text:
File:Working class dog.jpg

Summary
Working Class Dog cover

title: File:Working class dog.jpg


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Scottish term days

Scottish term and quarter days mark the four divisions (terms and quarters) of the legal year in Scotland. These were historically used as the days when contracts and leases would begin and end, servants would be hired or dismissed, and rent, interest on loans, and ministers' stipends would become due.

Description
The Term Days are Whitsunday and Martinmas, and together with Candlemas and Lammas they constitute the Quarter Days. These originally occurred on Christian holy days, corresponding roughly to old quarter days used in both Scotland and Ireland, with White Sunday or Whitsun occurring at the Easter Pentecost and thus moving around. These were mapped from the Julian to the Gregorian calendar and fixed in 1886 as 28 February, 28 May, 28 August and 28 November, and then later ratified by the Term and Quarter Days (Scotland) Act 1990.

Pre-1886
The Old Scottish Term and Quarter Days (Julian to Gregorian):
 * Candlemas (2 February)
 * Whitsunday (15 May)
 * Lammas (1 August)
 * Martinmas (11 November)

Post-1886
The new Scottish Term and Quarter Days (Gregorian post-1886):
 * 28 February
 * 28 May
 * 28 August
 * 28 November

History
Candlemas originally fell on 2 February, the day of the feast of the Purification, or the Presentation of Christ. This was celebrated in pre-Reformation times by candlelit processions. The tradition was started in the 5th century during the Roman celebration of Februa, and carried over into Scotland, where mothers of children born the previous year would march with candles, hoping to be purified by the Virgin Mary.

Whitsun was originally the feast of Pentecost, around which a great many christenings would occur, so it became associated with the colour white. Because the date of Pentecost moves each year, the legal Term Day of Whitsunday ( not to be confused with the church festival) was fixed in Scotland as 26 May in the Julian Calendar, which became 15 May under the Gregorian Calendar, adopted in Scotland in 1599.

Lammas was celebrated on 1 August, the day the first fruits of the harvest were offered, the name coming from the Anglo-Saxon for 'loaf-mass' or 'bread-feast'.

Martinmas, on 11 November, was originally the feast of Saint Martin of Tours, a 4th-century bishop and hermit.

In Scotland, 1886 saw the term dates for removals and the hiring of servants in towns changed to 28 February, 28 May, 28 August and 28 November. The original dates are now referred to as Old Scottish Term Days. The dates were regularised by the Term and Quarter Days (Scotland) Act 1990.

Modern use
The usage of term days is now most common in leases of farmland and less frequently with other leases. Other references to them tend to be historical or ceremonial.

The College of Justice (supreme courts of Scotland) no longer uses the term or quarter days to determine the terms of the Court of Session or High Court, instead dividing the legal year into winter (late September to last Friday before Christmas), spring (early January to late March) and summer (late April to early July) terms.

In the ancient universities, the academic terms were named after Martinmas, Candlemas and Whitsun, and at the University of St Andrews the two semesters continue to be named Martinmas and Candlemas.

title: Scottish term days


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Tabletop game

Tabletop games or tabletops are games that are normally played on a table or other flat surface, such as board games, card games, dice games, miniature wargames, or tile-based games.

Classification according to equipment used
Tabletop games can be classified according to the general form, or equipment utilized:

Games like chess and draughts are examples of games belonging to the board game category. Other games, however, use various attributes and cannot be classified unambiguously (e.g. Monopoly and many modern eurogames utilize a board as well as dice and cards).

For several of these categories there are sub-categories and even sub-sub-categories or genres. For instance, German-style board games, board wargames, and roll-and-move games are all types of board games that differ markedly in style and general interest.

Tabletop game components
The various specialized parts, pieces, and tools used for playing tabletop games may include:

 * Stopwatch, clock, hourglass or egg timer
 * , Miniature figures, pawn, or playing piece
 * Gambling chips or play money
 * Game board
 * Game box or container
 * Scoreboard or paper pad
 * Cardboard Counter, Dial Counter, Marker or peg for keeping score/tally
 * Pencil
 * Rule manuals
 * Ruler or measuring device
 * Modelling clay
 * Gamemaster's screen
 * Bowls, trays, or component organizers
 * Stickers often used in Legacy games
 * Card sleeves used in games that have a "Card Crafting System"
 * Randomizers such as:
 * Coins
 * Dice, which can include polyhedral dice
 * Dice tower or Dice cup
 * Playing cards, which can be collectible cards
 * Shuffling machine
 * Tiles
 * Tops, such as Teetotums or Dreidels
 * Drawstring bag
 * Spinners
 * Bones, Cowrie Shells, or Stick dice, used in ancient games

A refereed game could also include various aids to play, including scenario packs and computer game aids. Role-playing games can include campaign settings and various supplementary manuals and notes.

Classification according to elements of chance
As an alternative to classifying games by equipment, they can also be classified according to the elements of chance involved. In game theory, two fundamentally different elements of chance can play a role:
 * Chance due to outcome uncertainty, e.g. due to dice rolls or due to unknown cards being dealt during the game. Games in which outcome uncertainty plays a role are referred to as stochastic games as opposed to deterministic games.
 * Chance due to state uncertainty, e.g. due to the opponent's position or cards not being visible, or due to the simultaneous move character of the game. Games in which state uncertainty plays a role are referred to as partial or imperfect information games as opposed to full or perfect information games.

Examples of the chance classification for some well-known tabletop games are given in the table below.

Organizations
List of organizations that sponsor events featuring tabletop games:
 * Board Game Geek organizes BGG.CON
 * PAX hosts PAX Unplugged
 * Geek & Sundry promotes an annual International TableTop Day
 * The Organization of Gamers & Roleplaying Enthusiasts (O.G.R.E.s) organizes tabletop events for OMGcon
 * White Wolf Publishing's Camarilla
 * Wizards of the Coast own RPGA
 * The Historical Miniatures Gaming Society promotes historical miniatures wargaming and organizes wargaming events such as Historicon
 * SaltCON LLC organizes SaltCON and the Ion Award competition for unpublished tabletop games

Numerous independent, local groups run by gamers exist to play tabletop games. Additionally, many colleges have student run organizations pertaining solely to table top gaming. The Collegiate Association of Table Top Gamers is one such organization that has a few chapters at different schools.

Digital tabletop games
Digital tabletops games are digital variations of tabletop games, which include straight reproductions of existing physical tabletop games, video games that use tabletop game principles as part of their gameplay mechanics, and tabletop simulators that provide a virtual tabletop for conducting tabletop games online.

title: Tabletop game


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Talk:Seagate

Okay, we have two pages here about the same company, this one and Seagate Technology. I'm considering merging the info from this page into the main one. Also, there's a few places that also use the name (in particular a neighborhood of NYC near Brighton Beach), so I'm wondering if this page should be a disambig page once the move is done. What do you think? 66.106.14.146 19:16, 28 Jul 2004 (UTC)

title: Talk:Seagate