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Combustor

A combustor is a component or area of a gas turbine, ramjet, or scramjet engine where combustion takes place. It is also known as a burner, burner can, combustion chamber or flame holder. In a gas turbine engine, the combustor or combustion chamber is fed high-pressure air by the compression system. The combustor then heats this air at constant pressure as the fuel/air mix burns. As it burns the fuel/air mix heats and rapidly expands. The burned mix is exhausted from the combustor through the nozzle guide vanes to the turbine. In the case of a ramjet or scramjet engines, the exhaust is directly fed out through the nozzle.

A combustor must contain and maintain stable combustion despite very high air flow rates. To do so combustors are carefully designed to first mix and ignite the air and fuel, and then mix in more air to complete the combustion process. Early gas turbine engines used a single chamber known as a can-type combustor. Today three main configurations exist: can, annular, and cannular (also referred to as can-annular tubo-annular). Afterburners are often considered another type of combustor.

Combustors play a crucial role in determining many of an engine's operating characteristics, such as fuel efficiency, levels of emissions, and transient response (the response to changing conditions such as fuel flow and air speed).

Fundamentals
The objective of the combustor in a gas turbine is to add energy to the system to power the turbines, and produce a high-velocity gas to exhaust through the nozzle in aircraft applications. As with any engineering challenge, accomplishing this requires balancing many design considerations, such as the following:
 * Completely combust the fuel. Otherwise, the engine wastes the unburned fuel and creates unwanted emissions of unburned hydrocarbons, carbon monoxide (CO), and soot.
 * Low pressure loss across the combustor. The turbine which the combustor feeds needs high-pressure flow to operate efficiently.
 * The flame (combustion) must be held (contained) inside of the combustor. If combustion happens further back in the engine, the turbine stages can easily be overheated and damaged. Additionally, as turbine blades continue to grow more advanced and are able to withstand higher temperatures, the combustors are being designed to burn at higher temperatures and the parts of the combustor need to be designed to withstand those higher temperatures.
 * It should be capable of relighting at high altitude in an event of engine flame-out.
 * Uniform exit temperature profile. If there are hot spots in the exit flow, the turbine may be subjected to thermal stress or other types of damage. Similarly, the temperature profile within the combustor should avoid hot spots, as those can damage or destroy a combustor from the inside.
 * Small physical size and weight. Space and weight are at a premium in aircraft applications, so a well designed combustor strives to be compact. Non-aircraft applications, like power-generating gas turbines, are not as constrained by this factor.
 * Wide range of operation. Most combustors must be able to operate with a variety of inlet pressures, temperatures, and mass flows. These factors change with both engine settings and environmental conditions (i.e., full throttle at low altitude can be very different from idle throttle at high altitude).
 * Environmental emissions. There are strict regulations on aircraft emissions of pollutants like carbon dioxide and nitrogen oxides, so combustors need to be designed to minimize those emissions. (See Emissions section below)

Sources:

History
Advancements in combustor technology focused on several distinct areas; emissions, operating range, and durability. Early jet engines produced large amounts of smoke, so early combustor advances, in the 1950s, were aimed at reducing the smoke produced by the engine. Once smoke was essentially eliminated, efforts turned in the 1970s to reducing other emissions, like unburned hydrocarbons and carbon monoxide (for more details, see the Emissions section below). The 1970s also saw improvement in combustor durability, as new manufacturing methods improved liner (see Components below) lifetime by nearly 100 times that of early liners. In the 1980s combustors began to improve their efficiency across the whole operating range; combustors tended to be highly efficient (99%+) at full power, but that efficiency dropped off at lower settings. Development over that decade improved efficiencies at lower levels. The 1990s and 2000s saw a renewed focus on reducing emissions, particularly nitrogen oxides. Combustor technology is still being actively researched and advanced, and much modern research focuses on improving the same aspects.

Components
The case is the outer shell of the combustor, and is a fairly simple structure. The casing generally requires little maintenance. The case is protected from thermal loads by the air flowing in it, so thermal performance is of limited concern. However, the casing serves as a pressure vessel that must withstand the difference between the high pressures inside the combustor and the lower pressure outside. That mechanical (rather than thermal) load is a driving design factor in the case. The purpose of the diffuser is to slow the high-speed, highly compressed, air from the compressor to a velocity optimal for the combustor. Reducing the velocity results in an unavoidable loss in total pressure, so one of the design challenges is to limit the loss of pressure as much as possible. Furthermore, the diffuser must be designed to limit the flow distortion as much as possible by avoiding flow effects like boundary layer separation. Like most other gas turbine engine components, the diffuser is designed to be as short and light as possible. The liner contains the combustion process and introduces the various airflows (intermediate, dilution, and cooling, see Air flow paths below) into the combustion zone. The liner must be designed and built to withstand extended high-temperature cycles. For that reason liners tend to be made from superalloys like Hastelloy X. Furthermore, even though high-performance alloys are used, the liners must be cooled with air flow. Some combustors also make use of thermal barrier coatings. However, air cooling is still required. In general, there are two main types of liner cooling; film cooling and transpiration cooling. Film cooling works by injecting (by one of several methods) cool air from outside of the liner to just inside of the liner. This creates a thin film of cool air that protects the liner, reducing the temperature at the liner from around 1800 kelvins (K) to around 830 K, for example. The other type of liner cooling, transpiration cooling, is a more modern approach that uses a porous material for the liner. The porous liner allows a small amount of cooling air to pass through it, providing cooling benefits similar to film cooling. The two primary differences are in the resulting temperature profile of the liner and the amount of cooling air required. Transpiration cooling results in a much more even temperature profile, as the cooling air is uniformly introduced through pores. Film cooling air is generally introduced through slats or louvers, resulting in an uneven profile where it is cooler at the slat and warmer between the slats. More importantly, transpiration cooling uses much less cooling air (on the order of 10% of total airflow, rather than 20-50% for film cooling). Using less air for cooling allows more to be used for combustion, which is more and more important for high-performance, high-thrust engines. The snout is an extension of the dome (see below) that acts as an air splitter, separating the primary air from the secondary air flows (intermediate, dilution, and cooling air; see Air flow paths section below). The dome and swirler are the part of the combustor that the primary air (see Air flow paths below) flows through as it enters the combustion zone. Their role is to generate turbulence in the flow to rapidly mix the air with fuel. Early combustors tended to use bluff body domes (rather than swirlers), which used a simple plate to create wake turbulence to mix the fuel and air. Most modern designs, however, are swirl stabilized (use swirlers). The swirler establishes a local low pressure zone that forces some of the combustion products to recirculate, creating the high turbulence. However, the higher the turbulence, the higher the pressure loss will be for the combustor, so the dome and swirler must be carefully designed so as not to generate more turbulence than is needed to sufficiently mix the fuel and air. The fuel injector is responsible for introducing fuel to the combustion zone and, along with the swirler (above), is responsible for mixing the fuel and air. There are four primary types of fuel injectors; pressure-atomizing, air blast, vaporizing, and premix/prevaporizing injectors. Pressure atomizing fuel injectors rely on high fuel pressures (as much as 500 psi) to atomize the fuel. This type of fuel injector has the advantage of being very simple, but it has several disadvantages. The fuel system must be robust enough to withstand such high pressures, and the fuel tends to be heterogeneously atomized, resulting in incomplete or uneven combustion which has more pollutants and smoke.
 * Case
 * Diffuser
 * Liner
 * Snout
 * Dome / swirler
 * Fuel injector

The second type of fuel injector is the air blast injector. This injector "blasts" a sheet of fuel with a stream of air, atomizing the fuel into homogeneous droplets. This type of fuel injector led to the first smokeless combustors. The air used is just some of the primary air (see Air flow paths below) that is diverted through the injector, rather than the swirler. This type of injector also requires lower fuel pressures than the pressure atomizing type.

The vaporizing fuel injector, the third type, is similar to the air blast injector in that primary air is mixed with the fuel as it is injected into the combustion zone. However, the fuel-air mixture travels through a tube within the combustion zone. Heat from the combustion zone is transferred to the fuel-air mixture, vaporizing some of the fuel (mixing it better) before it is combusted. This method allows the fuel to be combusted with less thermal radiation, which helps protect the liner. However, the vaporizer tube may have serious durability problems with low fuel flow within it (the fuel inside of the tube protects the tube from the combustion heat).

The premixing/prevaporizing injectors work by mixing or vaporizing the fuel before it reaches the combustion zone. This method allows the fuel to be very uniformly mixed with the air, reducing emissions from the engine. One disadvantage of this method is that fuel may auto-ignite or otherwise combust before the fuel-air mixture reaches the combustion zone. If this happens the combustor can be seriously damaged.

Most igniters in gas turbine applications are electrical spark igniters, similar to automotive spark plugs. The igniter needs to be in the combustion zone where the fuel and air are already mixed, but it needs to be far enough upstream so that it is not damaged by the combustion itself. Once the combustion is initially started by the igniter, it is self-sustaining, and the igniter is no longer used. In can-annular and annular combustors (see Types of combustors below), the flame can propagate from one combustion zone to another, so igniters are not needed at each one. In some systems ignition-assist techniques are used. One such method is oxygen injection, where oxygen is fed to the ignition area, helping the fuel easily combust. This is particularly useful in some aircraft applications where the engine may have to restart at high altitude.
 * Igniter

Air flow paths
This is the main combustion air. It is highly compressed air from the high-pressure compressor (often decelerated via the diffuser) that is fed through the main channels in the dome of the combustor and the first set of liner holes. This air is mixed with fuel, and then combusted. Intermediate air is the air injected into the combustion zone through the second set of liner holes (primary air goes through the first set). This air completes the reaction processes, diluting the high concentrations of carbon monoxide (CO) and hydrogen (H2), and also helps cooling down the gases from combustion. Dilution air is air injected through holes in the liner at the end of the combustion chamber to cool the flue gas before it reaches the turbines. The air is carefully used to produce the uniform temperature profile desired in the combustor. However, as turbine blade technology improves, allowing them to withstand higher temperatures, dilution air is used less, allowing the use of more combustion air. Cooling air is air that is injected through small holes in the liner to generate a layer (film) of cool air to protect the liner from the combustion temperatures. The implementation of cooling air has to be carefully designed so it does not directly interact with the combustion air and process. In some cases, as much as 50% of the inlet air is used as cooling air. There are several different methods of injecting this cooling air, and the method can influence the temperature profile that the liner is exposed to (see Liner, above).
 * Primary air
 * Intermediate air
 * Dilution air
 * Cooling air

Can
Can combustors are self-contained cylindrical combustion chambers. Each "can" has its own fuel injector, igniter, liner, and casing. The primary air from the compressor is guided into each individual can, where it is decelerated, mixed with fuel, and then ignited. The secondary air also comes from the compressor, where it is fed outside of the liner (inside of which is where the combustion is taking place). The secondary air is then fed, usually through slits in the liner, into the combustion zone to cool the liner via thin film cooling.

In most applications, multiple cans are arranged around the central axis of the engine, and their shared exhaust is fed to the turbine(s). Can-type combustors were most widely used in early gas turbine engines, owing to their ease of design and testing (one can test a single can, rather than have to test the whole system). Can-type combustors are easy to maintain, as only a single can needs to be removed, rather than the whole combustion section. Most modern gas turbine engines (particularly for aircraft applications) do not use can combustors, as they often weigh more than alternatives. Additionally, the pressure drop across the can is generally higher than other combustors (on the order of 7%). Most modern engines that use can combustors are turboshafts featuring centrifugal compressors.

Can-annular

The next type of combustor is the "can-annular" combustor. Like the can-type combustor, can-annular combustors have discrete combustion zones contained in separate liners with their own fuel injectors. Unlike the can combustor, all the combustion zones share a common ring (annulus) casing. Each combustion zone no longer has to serve as a pressure vessel. The combustion zones can also "communicate" with each other via liner holes or connecting tubes that allow some air to flow circumferentially. The exit flow from the can-annular combustor generally has a more uniform temperature profile, which is better for the turbine section. It also eliminates the need for each chamber to have its own igniter. Once the fire is lit in one or two cans, it can easily spread to and ignite the others. This type of combustor is also lighter than the can type, and has a lower pressure drop (on the order of 6%). However, a can-annular combustor can be more difficult to maintain than a can combustor. Examples of gas turbine engines utilizing a can-annular combustor include the General Electric J79 turbojet and the Pratt & Whitney JT8D and Rolls-Royce Tay turbofans.

Annular

The final, and most-commonly used type of combustor is the fully annular combustor. Annular combustors do away with the separate combustion zones and simply have a continuous liner and casing in a ring (the annulus). There are many advantages to annular combustors, including more uniform combustion, shorter size (therefore lighter), and less surface area. Additionally, annular combustors tend to have very uniform exit temperatures. They also have the lowest pressure drop of the three designs (on the order of 5%). The annular design is also simpler, although testing generally requires a full size test rig. An engine that uses an annular combustor is the CFM International CFM56. Almost all of the modern gas turbine engines use annular combustors; likewise, most combustor research and development focuses on improving this type.

Double annular combustor
One variation on the standard annular combustor is the double annular combustor (DAC). Like an annular combustor, the DAC is a continuous ring without separate combustion zones around the radius. The difference is that the combustor has two combustion zones around the ring; a pilot zone and a main zone. The pilot zone acts like that of a single annular combustor, and is the only zone operating at low power levels. At high power levels, the main zone is used as well, increasing air and mass flow through the combustor. GE's implementation of this type of combustor focuses on reducing and  emissions. A good diagram of a DAC is available from Purdue. Extending the same principles as the double annular combustor, triple annular and "multiple annular" combustors have been proposed and even patented.

Emissions
One of the driving factors in modern gas turbine design is reducing emissions, and the combustor is the primary contributor to a gas turbine's emissions. Generally speaking, there are five major types of emissions from gas turbine engines: smoke, carbon dioxide (CO2), carbon monoxide (CO), unburned hydrocarbons (UHC), and nitrogen oxides (NOx).

Smoke is primarily mitigated by more evenly mixing the fuel with air. As discussed in the fuel injector section above, modern fuel injectors (such as airblast fuel injectors) evenly atomize the fuel and eliminate local pockets of high fuel concentration. Most modern engines use these types of fuel injectors and are essentially smokeless.

Carbon dioxide is a product of the combustion process, and it is primarily mitigated by reducing fuel usage. On average, 1 kg of jet fuel burned produces 3.2 kg of CO2. Carbon dioxide emissions will continue to drop as manufacturers improve the overall efficiency of gas turbine engines.

Unburned-hydrocarbon (UHC) and carbon-monoxide (CO) emissions are highly related. UHCs are essentially fuel that was not completely combusted. They are mostly produced at low power levels (where the engine is not burning all the fuel). Much of the UHC content reacts and forms CO within the combustor, which is why the two types of emissions are heavily related. As a result of this close relation, a combustor that is well optimized for CO emissions is inherently well optimized for UHC emissions, so most design work focuses on CO emissions.

Carbon monoxide is an intermediate product of combustion, and it is eliminated by oxidation. CO and OH react to form CO2 and H. This process, which consumes the CO, requires a relatively long time ("relatively" is used because the combustion process happens incredibly quickly), high temperatures, and high pressures. This fact means that a low-CO combustor has a long residence time (essentially the amount of time the gases are in the combustion chamber).

Like CO, Nitrogen oxides (NOx) are produced in the combustion zone. However, unlike CO, it is most produced during the conditions that CO is most consumed (high temperature, high pressure, long residence time). This means that, in general, reducing CO emissions results in an increase in NOx, and vice versa. This fact means that most successful emission reductions require the combination of several methods.

Afterburners
An afterburner (or reheat) is an additional component added to some jet engines, primarily those on military supersonic aircraft. Its purpose is to provide a temporary increase in thrust, both for supersonic flight and for takeoff (as the high wing loading typical of supersonic aircraft designs means that take-off speed is very high). On military aircraft the extra thrust is also useful for combat situations. This is achieved by injecting additional fuel into the jet pipe downstream of (i.e. after) the turbine and combusting it. The advantage of afterburning is significantly increased thrust; the disadvantage is its very high fuel consumption and inefficiency, though this is often regarded as acceptable for the short periods during which it is usually used.

Jet engines are referred to as operating wet when afterburning is being used and dry when the engine is used without afterburning. An engine producing maximum thrust wet is at maximum power or max reheat (this is the maximum power the engine can produce); an engine producing maximum thrust dry is at military power or max dry.

As with the main combustor in a gas turbine, the afterburner has both a case and a liner, serving the same purpose as their main combustor counterparts. One major difference between a main combustor and an afterburner is that the temperature rise is not constrained by a turbine section, therefore afterburners tend to have a much higher temperature rise than main combustors. Another difference is that afterburners are not designed to mix fuel as well as primary combustors, so not all the fuel is burned within the afterburner section. Afterburners also often require the use of flameholders to keep the velocity of the air in the afterburner from blowing the flame out. These are often bluff bodies or "vee-gutters" directly behind the fuel injectors that create localized low-speed flow in the same manner the dome does in the main combustor.

Ramjets
Ramjet engines differ in many ways from traditional gas turbine engines, but most of the same principles hold. One major difference is the lack of rotating machinery (a turbine) after the combustor. The combustor exhaust is directly fed to a nozzle. This allows ramjet combustors to burn at a higher temperature. Another difference is that many ramjet combustors do not use liners like gas turbine combustors do. Furthermore, some ramjet combustors are dump combustors rather than a more conventional type. Dump combustors inject fuel and rely on recirculation generated by a large change in area in the combustor (rather than swirlers in many gas turbine combustors). That said, many ramjet combustors are also similar to traditional gas turbine combustors, such as the combustor in the ramjet used by the RIM-8 Talos missile, which used a can-type combustor.

Scramjets

Scramjet (supersonic combustion ramjet) engines present a much different situation for the combustor than conventional gas turbine engines (scramjets are not gas turbines, as they generally have few or no moving parts). While scramjet combustors may be physically quite different from conventional combustors, they face many of the same design challenges, like fuel mixing and flame holding. However, as its name implies, a scramjet combustor must address these challenges in a supersonic flow environment. For example, for a scramjet flying at Mach 5, the air flow entering the combustor would nominally be Mach 2. One of the major challenges in a scramjet engine is preventing shock waves generated by combustor from traveling upstream into the inlet. If that were to happen, the engine may unstart, resulting in loss of thrust, among other problems. To prevent this, scramjet engines tend to have an isolator section (see image) immediately ahead of the combustion zone.

title: Combustor


text:
User talk:Dave6

Reg deletion of page of Prithvi Rao
Hi Dave6,

This is Raghavendra (User:U.raghavendra). I am a Campus Ambassador with Wikipedia for the India Education program. We had started the program early this month, and had given students tasks to do, starting from creating of user pages (For eg, http://en.wikipedia.org/wiki/Wikipedia:India_Education_Program/Courses/Fall_2011/Economics_of_the_Social_Sector_Year_2_Group_B). Which is why you would have seen some users creating their pages like Prithvi did

Can you kindly remove the delete tag from the user page of Prithvi so as to enable them to continue with their learning sessions and meeting other deadlines in their assignments?

Thanks Raghavendra — Preceding unsigned comment added by 122.169.69.218 (talk) 20:17, 25 July 2011 (UTC)

Proposed deletion of Spike Shooter

The article Spike Shooter has been proposed for deletion  because of the following concern:
 * product article of unclear notability, lacking significant WP:RS coverage. A search turned up incidental mentions and blog posts, but no substantial RS refs. Tagged for notability since 2012

While all constructive contributions to Wikipedia are appreciated, content or articles may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on |the article's talk page.

Please consider improving the article to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Dialectric (talk) 03:53, 3 July 2015 (UTC)

ArbCom elections are now open!
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New deal for page patrollers
Hi ,

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Under the new rule, you may find that you are temporarily unable to mark new pages as reviewed. However, this is nothing to worry about - most current experienced patrollers are being accorded the the new right without the need to apply, and if you have significant previous experience of patrolling new pages, we strongly encourage you to apply for the new right as soon as possible - we need all the help we can get, and we are now providing a dynamic, supportive environment for your work.

Find out more about this exiting new user right now at New Page Reviewers and be sure to read the new tutorial before applying. MediaWiki message delivery (talk) 04:28, 13 November 2016 (UTC)

RC Patrol-related Proposals in the 2016 Community Wishlist Survey
Greetings Recent Changes Patrollers!

This is a one-time-only message to inform you about technical proposals related to Recent Changes Patrol in the 2016 Community Wishlist Survey that I think you may be interested in reviewing and perhaps even voting for:

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

title: User talk:Dave6


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Talk:Kiki Dee

Name
Is this information correct? Born "Irene Chan Kee Eng". She doesn't look Asian to me. I tried to find information on the web but there's very few about her and on the website link (bottom of the page) it was mentioned that she was born "Pauline Matthews".

Someone should clarify this.

 * I don't know where this information comes from ? She's definitely a Yorkie and not of Asian descent.

If she was born Pauline Matthews, how did she come to call herself Kiki Dee? Is there a story behind that?

Awards
"During the 1970s and 1980s was regularly voted the top UK female singer". Really?? This needs sourcing or should be deleted. As an artist who had only 3 small hits in the entire 80s in the UK singles and albums charts it's inconceivable she was voted 'top UK female singer' during that time.Vauxhall1964 (talk) 01:49, 2 January 2008 (UTC)

Accident! HELP!
Got into the Discography inadvertently and before I knew it, something happened to the HTML there. Attempted to correct, but still not 100%. All the information is still there, but the layout is certainly off! — Preceding unsigned comment added by Andyprod1 (talk • contribs) 23:40, 20 February 2012 (UTC)

 * It's now back to where it was, I think. "Never bite off more than you can chew" - either Confusius, or my mum.

 * Derek R Bullamore (talk) 23:56, 20 February 2012 (UTC)

Northern soul
Kiki Dee is very much a Northern soul artist. If she intended to be so is another issue but that is true of many who have found their songs popular on this circuit. Her 2011 album 'I'm Kiki Dee' is from the 60's and,  according to the Amazon review, 'Kiki Dee's profile remains high amongst collectors of 60's Brit Girls, Northern Soul, and the massive crossover market of mainstream pop from the continued popularity of her live appearances. Her 'On a Magic Carpet Ride' appears on the 2011 album 'Northern Soul's Guilty Secrets' is highly collectible with copies going for over £300 [ http://www.guardian.co.uk/music/musicblog/2011/jan/28/kiki-dee-reissue] and is played on stations such as the BBC under the Northern Soul genre. It is also used on the 2010 film 'Soul Boy' - about Northern Soul.--Egghead06 (talk) 06:53, 7 April 2012 (UTC)

title: Talk:Kiki Dee


text:
User talk:Tom Sullivan

Welcome!

Hello,, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers: I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~); this will automatically produce your name and the date. If you need help, check out Where to ask a question, ask me on my talk page, or place  on your talk page and someone will show up shortly to answer your questions. Again, welcome! --Flockmeal 04:18, Dec 2, 2004 (UTC)
 * The five pillars of Wikipedia
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title: User talk:Tom Sullivan


text:
Lakeside, Ohio

Lakeside is a private community and census-designated place in Danbury Township, Ottawa County, Ohio, United States, on the shores of Lake Erie. It was formed in 1873 by members of the Methodist Church and remains a church-affiliated vacation resort and United Methodist Annual Conference site. It is one of only a few continuously operating Independent Chautauquas that persist in the 21st century. Located just west of the village of Marblehead, the community is approximately one square mile in size. The entire community is listed on the National Register of Historic Places as the Lakeside Historic District.

As an unincorporated community, Lakeside is governed by the Lakeside Association, a company whose CEO is the de facto leader of the community. Its current CEO is Charles Allen.

History
Lakeside was established under the jurisdiction of the Central Ohio Conference of the UMC in August 1873. It was first founded as a tented revivalist camp, where it served as a hub for Methodist teachings. Meanwhile, the Chautauqua movement began to gain popularity. Lakeside soon thereafter became a Chautauqua, allowing its popularity to pick up over time and gain popularity with other denominations. The first permanent building was erected somewhere near the Hoover Auditorium, with the first residential cottages being built at the shores of Lake Erie. Despite this increase in popularity and permanent habitation, the bulk of services had yet to be provided until 1875, when the first part of Hotel Lakeside was built.

Residential land and usage
The first residential buildings were cottages, which were sold out on plots of land with renewable 99 year leases. Over the years, residents built cottages and houses on their plots. Most cottages are in the Victorian style, although different styles are present throughout. Restaurants and shops also opened around the downtown park of Lakeside. The Lakeside Association eventually purchased additional land on the eastern side, enabling the community to grow. Recreation facilities, meeting halls, places of worship, and parks have been added over the years. The Lakeside Association is responsible for the upkeep of all roads and public services within Lakeside. Lakeside has had its own symphony orchestra since its founding in 1963 with its current conductor, Daniel Meyer. One of its most famous activities is shuffleboard, with its courts hosting lots of national tournaments throughout its history.

Architecture
Lakeside contains many well-preserved historic buildings. Many are in their original Victorian style. The Lakeside Association owns and operates a number of large assembly buildings:

 * Hoover Auditorium (Third St. between Walnut and Central)
 * South Auditorium (Sixth St. between Walnut and Central)
 * Orchestra Hall (corner of Second and Walnut)
 * Wesley Lodge (Fifth St. between Walnut and Central)

Places of worship:
 * Lakeside United Methodist Church (corner of Fifth and Central)
 * Chapel in the Woods (outdoor space along Maple past Seventh)
 * Hoover Auditorium (Third St between Walnut and Central) Lakeside's main auditorium, with a seating capacity of 3,000 persons, is used for worship services on Sunday mornings and headline events during the week.
 * Steele Memorial Bandstand & Pavilion, are used for Sunset Worship services (and other entertainment), Pavilion for early-to-middle late summer, and Pavilion in late summer.

Notable visitors
Because Lakeside has historically been a summer vacation destination with few year-round residents, the listed here made at least one stop to Lakeside during their lifetime. One person who still spends many summers here is Steve Hartman. Famous people who have been to Lakeside & Hoover Auditorium are the likes of:
 * Susan B. Anthony
 * William Jennings Bryan
 * Rose Woodallen Chapman (born in Lakeside)
 * Amelia Earhart
 * Eleanor Roosevelt
 * Robert McFerrin
 * Marian Anderson
 * Pat Boone
 * Emmylou Harris
 * Ulysses S. Grant
 * Rutherford B. Hayes
 * William McKinley
 * Champ Clark
 * Drew Pearson
 * J.C. Penney
 * Lowell Thomas
 * Jane Addams

title: Lakeside, Ohio


text:
Vomitory

Vomitory can refer to:

 * Vomitorium, an architectural feature in Ancient Roman amphitheatres
 * Vomitory (band), a death metal band from Sweden

title: Vomitory


text:
Iterative Viterbi decoding

Iterative Viterbi decoding is an algorithm that spots the subsequence S of an observation O = {o1, ..., on} having the highest average probability (i.e., probability scaled by the length of S) of being generated by a given hidden Markov model M with m states. The algorithm uses a modified Viterbi algorithm as an internal step.

The scaled probability measure was first proposed by John S. Bridle. An early algorithm to solve this problem, sliding window, was proposed by Jay G. Wilpon et al., 1989, with constant cost T = mn2/2.

A faster algorithm consists of an iteration of calls to the Viterbi algorithm, reestimating a filler score until convergence.

The algorithm
A basic (non-optimized) version, finding the sequence s with the smallest normalized distance from some subsequence of t is:

// input is placed in observation s[1..n], template t[1..m], // and distance matrix d[1..n,1..m] // remaining elements in matrices are solely for internal computations (int, int, int) AverageSubmatchDistance(char s[0..(n+1)], char t[0..(m+1)], int d[1..n,0..(m+1)]) { // score, subsequence start, subsequence end declare int e, B, E   t'[0] := t'[m+1] := s'[0] := s'[n+1] := 'e'

e := random do       e' := e	for i := 1 to n	do	d'[i,0] := d'[i,m+1] := e	(e, B, E)  := ViterbiDistance(s', t', d') e := e/(E-B+1) until (e == e')

return (e, B, E) }

The ViterbiDistance procedure returns the tuple (e, B, E), i.e., the Viterbi score "e" for the match of t and the selected entry (B) and exit (E) points from it. "B" and "E" have to be recorded using a simple modification to Viterbi.

A modification that can be applied to CYK tables, proposed by Antoine Rozenknop, consists in subtracting e from all elements of the initial matrix d.

title: Iterative Viterbi decoding


text:
Jazz Jackrabbit 2

Jazz Jackrabbit 2 is a 1998 platform game produced by Epic MegaGames. It was released for Windows, and later for Macintosh. Like the first game, Jazz Jackrabbit, Jazz Jackrabbit 2 is a side-scrolling platform game but features additional multiplayer options, including the ability to play over a LAN or the Internet. The game was re-released on GOG.com along with the first game on November 30, 2017.

Gameplay
Just like its predecessor, Jazz Jackrabbit 2 is a 2D side-scroller that incorporates elements of shooting and platforming. The player must venture through a series of levels populated with enemies and environmental hazards that may hinder the player's progress. The goal is to reach the level's exit, usually indicated by an exit sign, whilst overcoming obstacles and hazards through the use of running and jumping as well as removing enemies and obstructions through the use of shooting and stomping.

The player is given a selection of characters to choose from, namely, Jazz, Spaz, and eventually (in the subsequent expansions) Lori. Each character has certain traits that are exclusive to them. For an example, Jazz can launch himself vertically higher than others, Spaz can double jump, and Lori can dash through enemies. Each Character is equipped with a gun that can fire an inexhaustible supply of projectiles in a straight manner. However, the player can encounter additional ammunition that can provide greater fire-power and range but with limiting ammo. These ammo types can result in different weapon behaviors such as a flamethrower, freeze ray, and explosives.

In addition to ammo, players will usually come across certain items and power-ups to aid the player. Some of these may include a 1-up that gives the player an extra life, a massive variety of food that when enough is collected gives the player a short period of invincibility in the form of a "sugar rush", a variety of diamonds that when enough is collected gives the player an extra life, a carrot that boosts the player's health, a bird in a cage that once is liberated will follow the player while automatically firing at any nearby enemy until the player takes damage, and rapid fire which decreases the delay between shots with every pick up without the player being required to rapidly tap the fire button, although, this power up will reset itself every time the player loses a life.

Also scattered throughout the levels are coins to collect. These are used as currency for when one encounters the merchant. If enough coins are collected, the merchant will teleport the player to a secret location in the level that is usually filled with power-ups and other goodies.

Multiplayer
The game's split-screen mode supports up to four players, whereas online can support up to 32. The game also has local TCP/IPX network support. There are five multiplayer game modes: Cooperative (where players work together in the game's single-player campaign), Battle (basically a deathmatch), Race (in which the first to complete all laps wins), Treasure Hunt (in which the first to collect 100 diamonds and find the exit wins the match), and Capture the Flag.

Plot
Devan Shell builds a time machine to rewrite history and eliminate hares. He steals Jazz and Eva's wedding ring to complete the machine. Jazz chases his nemesis Devan Shell through time, in order to retrieve the ring. When his plans fail, Devan unleashes demons from Hell and also transforms into a demon. Jazz manages to defeat Devan, takes the ring and finally marries Eva.

Development
Jazz Jackrabbit 2 was produced by Epic MegaGames, now known as Epic Games, as the sequel to Jazz Jackrabbit. It was accidentally confirmed in August 1994 by Arjan Brussee. It was released in 1998 for PCs running Windows, and later for Macintosh computers.

Jazz Jackrabbit 2 has a bundled level editor called Jazz Creation Station (JCS), allowing players to create their own levels. The level editor was not included in the Mac versions or shareware editions.

Releases
There were several variants and releases of Jazz Jackrabbit 2.

Released on April 10, 1998, this is a promotional shareware game. It featured three single-player levels and two multiplayer levels. It was released to promote the game. The three single-player levels from the Shareware Edition were later included in the commercial release of the game.
 * Jazz Jackrabbit 2: Shareware Edition

This Christmas edition was released on November 6, 1998 for the PC in North America. Unlike the previous holiday editions, this game is commercial rather than shareware. It includes three single-player levels as well as a new boss and additional multiplayer levels.
 * Jazz Jackrabbit 2: Holiday Hare '98

This Easter edition was released on March 15, 1999 for the PC in Europe (with a subsequent release in Poland by LK Avalon on June 19 which added Polish language in the options). This game introduces Jazz's sister Lori as another playable character. When Lori dies, her face is immolated and she falls over. It also adds an extra episode to the original Jazz Jackrabbit 2, called The Secret Files. This episode consists of three different zones, each one with three levels. New tiles are also added to The Secret Files, most of them from the first Jazz Jackrabbit. The LK Avalon release can be found in the GOG.com re-release.
 * Jazz Jackrabbit 2: The Secret Files

Released in 1999, this is a shareware game to promote The Secret Files. It is identical to the standard shareware version, but it includes the ability to play as Lori, as well as two new single-player levels in addition to the standard shareware version's levels.
 * Jazz Jackrabbit 2: The Secret Files Shareware Edition

This Christmas edition is an enhanced version of Holiday Hare '98, featuring Lori as a playable character. It was going to be released on November 25, 1999 for the PC across Europe, but the publisher, Project Two Interactive, went bankrupt before the release date. It was eventually released in Poland by LK Avalon. A limited European release followed shortly after. This version is based on the engine of The Secret Files and can be found in the GOG.com re-release.
 * Jazz Jackrabbit 2: The Christmas Chronicles

Reception
Jazz Jackrabbit 2 received positive reviews. MacADDICT's reviewer John Lee praised the Mac version's fluent gameplay, but criticised it for not adding anything new to the genre, which he considered "old fashioned". Trevor Covert of MacNN described the gameplay as "addicting" and praised the graphics, but Next Generation called the PC version "unimpressive". PC Zone gave the same PC version an above-average review over a month before its European release date.

The game sold 29,000 units in the U.S. by October 2001. Despite good reviews, sales were insufficient and resulted in some financial loss for Gathering of Developers.

title: Jazz Jackrabbit 2


text: User talk:67.160.45.93

title: User talk:67.160.45.93


text:
User talk:Superpanoramix

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title: User talk:Superpanoramix


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User talk:Vitt

Welcome!

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User talk:Alfy

Welcome!

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title: User talk:Alfy


text:
Joydrop

Joydrop is a Canadian alternative rock band active in the late 1990s and early 2000s from Toronto, Ontario. The band reunited in 2017. The band consists of vocalist Tara Slone, guitarist Thomas Payne, bassist Tom McKay, and drummer Tony Rabalao.

History
Joydrop was formed in Toronto in 1997. Rabalao and McKay knew each other through recording sessions and tour work and McKay had seen Payne play live a number of times. Once Payne joined they found Slone by placing an ad in Now magazine.

The band's first CD, Metasexual, was released in 1999 on the Tommy Boy label. They performed music from the album at the Horseshoe Tavern in Toronto in March that year. The song "Beautiful" from that album was on the Canadian charts and was used on the film Attraction; it played during the end credits. "Beautiful" was also featured on the syndicated TV show VIP and in the film Ginger Snaps 2: Unleashed(it played during the end credits).

Viberate, the band's second album, was also released on Tommy Boy.

The band's single "Sometimes Wanna Die" was featured on MTV2 in the US during the summer of 2001, thanks in part to a music video featuring Tommy Lee. The song was one of the top 100 most played songs on radio in Canada in 2001, ranking #65.

Joydrop appeared as themselves, performing their two hit songs, on an episode of Special Unit 2.

Joydrop was nominated for a Juno Award for Best New Group in 2002.

On the 22nd anniversary of the album's release, Slone reminisced about what caused the band to break up:

"Our fans might not know that our lifespan as a band was cut short partially by circumstances beyond our control. First, our song “Sometimes Wanna Die” was removed from all radio stations in the US after 9/11. Then, as we were getting set to release our second single, our record company was absorbed by a bigger one, and we lost our record deal. We had no more budget to tour or release our new song, and we didn’t own our master recording. This stuff happens in the record business all then time… but it happened to us, and it sucked. Still does."

Following the band's breakup, Slone released a solo album and was a contestant on Rock Star: INXS. Tony Rabalao also went solo and put out a CD under the name Lehlo but plays in Slone's band as well. Thomas McKay is a producer with a recording studio www.exetersoundstudios.com He worked on Slone's and Rabalao's solo CDs as well as numerous other Canadian, American and British bands. Thomas Payne is writing and producing music for stage in Stratford Ontario. As of 2010, Slone is part of Breakfast Television on CKAL-DT (Citytv Calgary).

On April 2, 2017, Joydrop reunited for a performance at Hometown Hockey's tour stop in Guelph, Ontario. The gig led to further performances in 2017, including a show at the Bovine on August 25, 2017 in Toronto.

Singles

 * "Beautiful" (1999) – No. 20 US Alternative Songs, No. 87 AUS
 * "If I Forget" (exclusive to Canada) (1999)
 * "Spiders" (exclusive to US) (2000)
 * "Sometimes Wanna Die" (2001)
 * "American Dream Girl" (2001)

title: Joydrop


text:
Leroy Grumman

Leroy Randle "Roy" Grumman (4 January 1895 – 4 October 1982) was an American aeronautical engineer, test pilot, and industrialist. In 1929, he co-founded Grumman Aircraft Engineering Co., later renamed Grumman Aerospace Corporation, and now part of Northrop Grumman.

Early life
Grumman was born in Huntington, New York. His forebears had Connecticut roots and owned a brewery. When he was a child, his father, George Tyson Grumman, owned and operated a carriage shop, and later worked for the post office. From an early age, "Red Mike" (a nickname he gained because of his red-blond hair) demonstrated an interest in aviation, and in his 20 June 1911 high school salutatory address at Huntington High School, Grumman predicted that "[t]he final perfection of the aeroplane will be one of the greatest triumphs that man has ever gained over nature."

Grumman earned a Bachelor of Science degree in mechanical engineering from Cornell University in 1916. His first job was in the engineering department of the New York Telephone Company. After the United States entered World War I, he enlisted in the U.S. Naval Reserve in June 1917 as a machinist's mate, 2nd class, and was sent to Columbia University for a course on "subchaser" engines.

Aviation career
Although Grumman applied for flight training, he failed a medical evaluation when the examining board incorrectly diagnosed flat feet. A clerical error, however, had him report to a course in aircraft inspection for pilot trainees at Massachusetts Institute of Technology. Without revealing the error in classification, he entered primary flight training at Naval Air Station Miami and successfully completed advanced flight training in Pensacola, Florida, in September 1918. Raymond P. Applegate, his flight instructor, recalled several years later that his young charge "was very, very reticent. Most of the guys, after they [learned to] fly, they became tougher than hell. Grumman didn't." He was commissioned an ensign (as naval aviator No. 1216), eventually becoming a flight instructor, and assigned to a bombing squadron.

After one tour of duty, the U.S. Navy sent him to Massachusetts Institute of Technology to study the brand new discipline of aeronautical engineering. After the completion of the course, Grumman's first posting, along with a promotion to lieutenant, was at the League Island Naval Yard as an acceptance test pilot for Curtiss- and Navy-built flying boats.

In 1919, the U.S. Navy stationed Grumman at Loening Aeronautical Engineering Corporation in New York City as the project engineer to supervise the firm's construction of 52 Loening M-8 monoplane observation/fighter aircraft under contract to the Navy. His duties included test flying as well as serving as the production supervisor. Grover Loening, the company president, was so impressed with his work that he offered Grumman a position. After a reduction in rank to ensign in the peacetime U.S. Navy, Grumman resigned his Naval commission in October 1920, becoming a test pilot flying various types of Loening amphibians while doing some design and development on these aircraft. He quickly moved up in the Loening organization, becoming the factory manager and then general manager with responsibility over aircraft design, a position he held until the company was sold in 1929 on the eve of the Depression to Keystone Aircraft. Keystone closed their Manhattan factory and moved operations to Bristol, Pennsylvania.

Company founding
Unwilling to leave Long Island to continue working for Keystone, Grumman joined fellow Loening employees Jake Swirbul and William Schwendler in resolving that their best option was to quit and form their own company. Grumman mortgaged his house for $16,950 and Swirbul's mother borrowed $6,000 from her employers to help set up Grumman Aeronautical Engineering Co. The co-founders were soon joined by Ed Poor, Grover Loening's business manager, and E. Clinton Towl, who had recently come from Wall Street. These five men formed the company's inner circle of management for the next 50 years. Loening and his brother, Albert P. Loening, also became investors. The company was named after its largest stockholder and first president.

On 2 January 1930, the company took possession of an abandoned auto showroom garage in Baldwin, New York, that had once been the Cox-Klemin Aircraft Co. factory. Initially, the new company, with only 18 people on salary, had contracts to repair damaged Loening amphibians (surplus parts had been bought from the Loening works) and traded on its expertise in working with aluminum by building aluminum floats and producing aluminum truck bodies. The first project of the new company involved Grumman and Swirbul, as president and vice-president, on hands and knees, sorting out and matching nuts and bolts, prior to assembling Loening floats.

Swirbul and Grumman oversaw the day-to-day operations of the company. While the employees in the plant felt comfortable calling the outgoing Swirbul "Jake", no one ever called Grumman anything but "Mr. Grumman" out of deference to his reserved manner and respect for his skill as an engineer and designer. Dick Hutton, Grumman engineer and later senior vice-president of engineering described him as a "great engineer, respected by many ..." To family and close friends, he was invariably known as "Roy".

Having been told of the U.S. Navy's desire for retractable landing gear, Leroy Grumman was awarded, Retractable Landing Gear for Airplanes in 1932, based on an earlier design that he had developed for the Loening Air Yacht. The innovative, manually operated landing gear which progressed from a heavy and unreliable design to a more sturdy version helped his company win contracts from the U.S. Navy. When the Grumman Company received its first U.S. Navy production contract for a two-seater biplane fighter, the FF-1, it featured Grumman's trademark "splayed out" landing gear. Grumman's ability as an engineer and designer was characterized by a Grumman Company engineer as that of "'a master of the educated hunch' who could foresee technical problems and their solutions." He single-handedly invented the famous "Sto-Wing" wing-panel folding system that revolutionized carrier aircraft storage and handling, pioneered on the F4F-4 Wildcat subtype. He worked out the solution by sticking paper clips into a soap eraser to find the pivot point that made the Sto-Wing possible.

Although Grumman realized the importance of his close relationship with the U.S. Navy, by the mid-1930s, he began to design aircraft for the commercial market with the development of the G-21 "Goose" amphibian and the G-22 "Gulfhawk", civil version of the Grumman F3F carrier-based fighter.

Expansion
As the company expanded, it moved to bigger quarters – to Valley Stream in 1931, Farmingdale in 1932, and finally Bethpage in 1937. In 1934, a company legend grew up around the number "250" which marked the zenith for expansion in Grumman's mind. He reasoned that if there were more than 250 employees, "it's going to be too big and we're going to lose control of it. That's where we ought to stop." Company accountant Towl was eventually deputized to tell Grumman that the payroll was already at 256.

Although Grumman resisted the "expansionist" efforts that Swirbul advocated, employment grew from 700 in 1939 to 25,500 in 1943, with the company known as the "Grumman Iron Works" (a name derived from their product line's rugged structure and a design philosophy espoused by both Swirbul and Grumman) becoming the primary source for U.S. Navy aircraft.

Management style
Despite his innate shyness, Grumman's management style included a "hands-on" approach where he could talk comfortably with both executives and factory floor workers. His relationship with Swirbul was unusual. They resolved early in their partnership to work out of one office; both men further pledged that any problems or conflicts that arose between them would not fester, and that neither man would leave the office until they came to an understanding.

During an unusually hectic period in the summer of 1944, Grumman sought a release from tension in a unique manner. Seeking out company test pilot Selden "Connie" Converse, he asked for a check out in a "hot ship": the front line F6F Hellcat. After a 10-minute cockpit check, Grumman waved Converse away, started the engine and was soon taxiing down the runway and into the air on a half-hour joy ride. Even though he hadn't flown for years, as he had in the past, when things built up, he would "take his troubles upstairs and leave them there." The factory test pilots observed that Grumman had the flaps down as he taxied back to the flight line, and insisted that he pay the standard $1.00 fine for a flight infraction. Grumman stuffed a five-dollar bill into the party fund container, confiding that it was to make up "for things he'd done in the air that they hadn't seen."

World War II
By 1939, as World War II began, Grumman's struggling company could hardly be considered an industrial giant, with all of its property relying on the services of a single security guard, yet the company was obtaining important civil and military contracts. However, the next year saw dramatic changes in the company's fortunes as the war in Europe prompted France and Britain to order F4F Wildcats, Grumman's first monoplane fighter design, still bearing his original signature design element, the retractable undercarriage that had been created in 1932.

Beginning with the Wildcat and then with the F6F Hellcat fighters, Grumman and Swirbul remained the key figures in the design office. As the war progressed, the pair continued to advance new projects, including the largest single-engine aircraft of World War II, the TBF Avenger torpedo bomber and F7F Tigercat and F8F Bearcat fighter aircraft.

Near the end of the war, Grumman was given a penicillin injection to combat pneumonia, resulting in a severe reaction that affected his eyesight. Although he was not entirely blind, his vision was greatly affected; Grumman began to "become less visible" in the company.

Postwar
By March 1945, Grumman oversaw a production effort where all types reached a record 664 aircraft manufactured in one month, although Swirbul had "farmed out" production to a vast chain of subsidiary and licensed manufacturing plants. Like its competitors, Grumman Aircraft Engineering Corporation experienced severe postwar downsizing, dropping from 20,500 to 5,400 employees immediately after the cessation of hostilities. It was an extremely hard decision because the company had been careful to cultivate a positive workplace culture; when a canvass was made of employees who wanted to "move on" at war's end, only 126 came forward.

Swirbul realized his wartime expansion would have to be abandoned, and together with Grumman made the momentous call for a complete layoff of all staff. However, Grumman personally retained as many veteran employees as possible, calling back the most proficient and experienced "hands", predominantly those who had 10 years of service. Grumman stepped down from the role of company president in 1946, but continued to play an active role in management.

Building with the core group, Swirbul and Grumman restructured the company, first solidifying its long-term contracts with the U.S. Navy, beginning a continuous line of new combat aircraft. Grumman's first venture into jet aircraft, the F9F Panther, became operational in 1949, although the company's most significant postwar successes came in the 1960s with the A-6 Intruder and in the 1970s with the F-14 Tomcat. Although the relationship that Grumman had established with the U.S. Navy was the hallmark of the company's success, a set of new projects were initiated with the development of an engineering department, set up in much the same way that he had started out, with a small core of eight engineers given the mandate to explore new technology.

With Swirbul's death on 28 June 1960, Grumman lost not only a close friend but his "right hand" during a time when he was faced with critical decisions as to the company's future. He successfully guided the company into finding new markets for new products. In the move to diversification, he again entered the commercial civil aviation market, introducing landmark designs such as the Ag Cat aerial application and crop-dusting biplane and the Gulfstream I, Gulfstream II, Gulfstream III and Gulfstream IV series of executive turboprop and jet transport aircraft. Although his role as chairman became reduced, Grumman's counsel was paramount and when the Gulfstream project was launched, two models of a high-wing and low-wing configuration were set up outside his office. Grumman personally made the decision to go with "the low wing".

While continuing the company tradition of aircraft production for naval aviation, Grumman pushed for a shift in priorities resulting in the Space Steering Group, a space program that culminated in the design and production of the Apollo program's Lunar Excursion Module (LEM) that landed astronauts on the Moon in 1969. During that same year, the company was rebranded as Grumman Aerospace Corporation. Throughout this period, Grumman's eyesight continued to fail, and he "took to wearing dark glasses" which further limited his mobility.

Later life
On 19 May 1966, Grumman retired as chairman of Grumman, but was elected honorary chairman for his lifetime, remaining as a director until 15 June 1972. He continued to visit the company's facilities until his health began to fail in the early 1980s, as diabetes robbed him of the last "vestiges of his eyesight." Grumman and his family retained their 8,299 sq ft, 2.5 acre waterfront estate at 77 Bayview Road in Plandome Manor on Long Island where, after a long illness, he died at the North Shore University Hospital in nearby Manhasset on 4 October 1982, aged 87.

Honors and tributes
A number of honors have been bestowed on Grumman including the Medal for Merit from the U.S. President (1948), an honorary Doctor of Engineering degree by Brooklyn Polytechnic Institute in 1950, the Daniel Guggenheim Medal for aeronautics pioneering, and the NAS Award in Aeronautical Engineering (1968) from the National Academy of Sciences.

In 1972, Grumman was inducted in the National Aviation Hall of Fame, the International Air & Space Hall of Fame in 1973, and the Long Island Technology Hall of Fame in 2002.

The USNS Leroy Grumman (T-AO-195), a United States Navy fleet replenishment oiler, christened by his three daughters, was launched in 1988 and delivered to the U.S. Navy in 1989. In January 2011, a Civil Air Patrol Squadron from Northport, Long Island, New York, was renamed in his honor: the former Suffolk County Cadet Squadron VII now calls itself the Leroy R. Grumman Cadet Squadron.

In 1953, Grumman was elected to the board of trustees of his alma mater, Cornell University, and donated $110,000 for a new squash building which now bears his name, as does an office and lab space on the campus.

"We always tried to do a solid job."

title: Leroy Grumman


text:
User talk:JaredKatyaFan

Welcome!

Hello,, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers: I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~); this will automatically produce your name and the date. If you need help, check out Where to ask a question, ask me on my talk page, or place  on your talk page and someone will show up shortly to answer your questions. Again, welcome! --Flockmeal 04:30, Dec 2, 2004 (UTC)
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Ben Sheets
Greetings. Just saw your work on Ben Sheets. Good job on the article - sorry that I didn't see the note saying you were still working on it. (I didn't check the history of the article until after I made the edits.) R ADICAL B ENDER  ★  23:31, 2 Dec 2004 (UTC)

title: User talk:JaredKatyaFan


text:
Micellar electrokinetic chromatography

Micellar electrokinetic chromatography (MEKC) is a chromatography technique used in analytical chemistry. It is a modification of capillary electrophoresis (CE), extending its functionality to neutral analytes, where the samples are separated by differential partitioning between micelles (pseudo-stationary phase) and a surrounding aqueous buffer solution (mobile phase).

The basic set-up and detection methods used for MEKC are the same as those used in CE. The difference is that the solution contains a surfactant at a concentration that is greater than the critical micelle concentration (CMC). Above this concentration, surfactant monomers are in equilibrium with micelles.

In most applications, MEKC is performed in open capillaries under alkaline conditions to generate a strong electroosmotic flow. Sodium dodecyl sulfate (SDS) is the most commonly used surfactant in MEKC applications. The anionic character of the sulfate groups of SDS causes the surfactant and micelles to have electrophoretic mobility that is counter to the direction of the strong electroosmotic flow. As a result, the surfactant monomers and micelles migrate quite slowly, though their net movement is still toward the cathode. During a MEKC separation, analytes distribute themselves between the hydrophobic interior of the micelle and hydrophilic buffer solution as shown in figure 1.

Analytes that are insoluble in the interior of micelles should migrate at the electroosmotic flow velocity, $$u_o$$, and be detected at the retention time of the buffer, $$t_M$$. Analytes that solubilize completely within the micelles (analytes that are highly hydrophobic) should migrate at the micelle velocity, $$u_c$$, and elute at the final elution time, $$t_c$$.

Theory
The micelle velocity is defined by:

 * $$u_c= u_p+u_o$$

where $$u_p$$ is the electrophoretic velocity of a micelle.

The retention time of a given sample should depend on the capacity factor, $$k^1$$:

 * $$k^1=\frac{n_c}{n_w}$$

where $$n_c$$ is the total number of moles of solute in the micelle and $$n_w$$ is the total moles in the aqueous phase. The retention time of a solute should then be within the range:

 * $$ t_M\le t_r\le t_c $$

Charged analytes have a more complex interaction in the capillary because they exhibit electrophoretic mobility, engage in electrostatic interactions with the micelle, and participate in hydrophobic partitioning.

The fraction of the sample in the aqueous phase, $$R$$, is given by:

 * $$ R= \frac{u_s-u_c}{u_o-u_c}$$

where $$u_s$$ is the migration velocity of the solute. The value $$R$$ can also be expressed in terms of the capacity factor:

 * $$ R=\frac{1}{1+k^1}$$

Using the relationship between velocity, tube length from the injection end to the detector cell ($$L$$), and retention time, $$u_{o}= L/t_M$$, $$u_{c}= L/t_{c}$$ and $$u_s = L/t_r$$, a relationship between the capacity factor and retention times can be formulated:

 * $$ k^1=\frac{t_r-t_M}{t_M(1-(t_r/t_c))}$$

The extra term enclosed in parentheses accounts for the partial mobility of the hydrophobic phase in MEKC. This equation resembles an expression derived for $$k^1$$ in conventional packed bed chromatography:

 * $$ k=\frac{t_r-t_M}{t_M}$$

A rearrangement of the previous equation can be used to write an expression for the retention factor:

 * $$t_r =\left ( \frac{1+k^1}{1+(t_M/t_c)k^1} \right )t_M$$

From this equation it can be seen that all analytes that partition strongly into the micellar phase (where $$k^1$$ is essentially ∞) migrate at the same time, $$t_c$$. In conventional chromatography, separation of similar compounds can be improved by gradient elution. In MEKC, however, techniques must be used to extend the elution range to separate strongly retained analytes.

Elution ranges can be extended by several techniques including the use of organic modifiers, cyclodextrins, and mixed micelle systems. Short-chain alcohols or acetonitrile can be used as organic modifiers that decrease $$t_M$$ and $$k^1$$ to improve the resolution of analytes that co-elute with the micellar phase. These agents, however, may alter the level of the EOF. Cyclodextrins are cyclic polysaccharides that form inclusion complexes that can cause competitive hydrophobic partitioning of the analyte. Since analyte-cyclodextrin complexes are neutral, they will migrate toward the cathode at a higher velocity than that of the negatively charged micelles. Mixed micelle systems, such as the one formed by combining SDS with the non-ionic surfactant Brij-35, can also be used to alter the selectivity of MEKC.

Applications
The simplicity and efficiency of MEKC have made it an attractive technique for a variety of applications. Further improvements can be made to the selectivity of MEKC by adding chiral selectors or chiral surfactants to the system. Unfortunately, this technique is not suitable for protein analysis because proteins are generally too large to partition into a surfactant micelle and tend to bind to surfactant monomers to form SDS-protein complexes.

Recent applications of MEKC include the analysis of uncharged pesticides, essential and branched-chain amino acids in nutraceutical products, hydrocarbon and alcohol contents of the marjoram herb.

MEKC has also been targeted for its potential to be used in combinatorial chemical analysis. The advent of combinatorial chemistry has enabled medicinal chemists to synthesize and identify large numbers of potential drugs in relatively short periods of time. Small sample and solvent requirements and the high resolving power of MEKC have enabled this technique to be used to quickly analyze a large number of compounds with good resolution.

Traditional methods of analysis, like high-performance liquid chromatography (HPLC), can be used to identify the purity of a combinatorial library, but assays need to be rapid with good resolution for all components to provide useful information for the chemist. The introduction of surfactant to traditional capillary electrophoresis instrumentation has dramatically expanded the scope of analytes that can be separated by capillary electrophoresis.

MEKC can also be used in routine quality control of antibiotics in pharmaceuticals or feedstuffs.

title: Micellar electrokinetic chromatography


text: Category:California State Historic Parks


text:
User talk:Waiting4beckett

Welcome! Feel free to say something. --Waiting4beckett 16:17, 28 Jan 2005 (UTC)

Hi, thank you for creating the page on Frederic Glazer, librarian. I am a relative of his and my family always wondered who created this page…we have some guesses. I understand if you”d prefer to remain anonymous, just know that my family and I appreciate your including him in this reference. Sheridan71 (talk) 20:40, 7 February 2022 (UTC)

title: User talk:Waiting4beckett


text:
Talk:Yekaterina Lobazyuk

Hey all, started and finished the article on Lobaznyuk, what do you think? She's one of my favorite gymnasts of all time, so I thought I might as well do an article on her (she's an Olympic medalist, after all. If you have any ideas for changes or additions, post on this page or post a message in my inbox.  Thanks!

Jared Buck 04:32, 2 Dec 2004 (UTC)

Need a little help, i don't know how to fix the article title so it displays "Lobaznyuk" instead of "Lobazyuk", i made a typo when originally typing the article :( Can one of the admins fix this error?

--172.194.171.200 01:10, 3 Jan 2005 (UTC)

title: Talk:Yekaterina Lobazyuk


text:
John MacLean (ice hockey)

John Carter MacLean (born November 20, 1964) is a Canadian professional ice hockey coach and former player. He is the assistant coach for the New York Islanders of the National Hockey League (NHL). He spent the majority of his playing career as a member of the New Jersey Devils, and also spent time with the San Jose Sharks, New York Rangers and Dallas Stars.

Playing career
As a youth, MacLean played in the 1977 Quebec International Pee-Wee Hockey Tournament with a minor ice hockey team from Oshawa.

MacLean was selected 6th overall in the 1983 NHL Entry Draft. He was selected as the 1st choice of the New Jersey Devils. MacLean made his Devils debut on October 5, 1983 against the New York Rangers. Perhaps his most memorable moment as a Devil came on April 3, 1988, when he scored a goal in overtime against the Chicago Blackhawks to send the Devils to the playoffs for the first time. Following this breakthrough year, MacLean notched three straight 40-goal seasons before he was forced to miss the 1991–92 season due to a serious knee injury sustained during a preseason game. During his tenure with the Devils, MacLean won the Stanley Cup in 1995 while serving as the team's alternate captain. He remained with the Devils until December 7, 1997 when he was traded to the San Jose Sharks. After finishing the 1997–98 season with the Sharks, MacLean signed as a free agent with the New York Rangers in July 1998. The Rangers traded MacLean to the Dallas Stars in February 2001.

On June 7, 2002, MacLean retired from hockey after 18 seasons. He played a total 1,194 games, scoring 413 goals, adding 429 assists for 842 career points, and was the all-time leading scorer for the New Jersey Devils until March 17, 2009, when his record was surpassed by Patrik Eliáš.

MacLean has been a resident of Verona, New Jersey since 1991.

Coaching career
In September 2002, MacLean joined the coaching staff of the New Jersey Devils, and served as an assistant coach until July 2009. He earned his second Stanley Cup, as an assistant coach, in 2003. In 2007, he was a candidate for the head coach position but the job was given to Brent Sutter, and MacLean remained as assistant coach.

On June 9, 2009, Brent Sutter resigned as head coach of the Devils and remarked that MacLean was ready to be head coach. On July 13, 2009, MacLean was named head coach of the Lowell Devils.

On June 17, 2010, MacLean was named head coach of the New Jersey Devils.

On December 23, 2010, the Devils were sporting a 9–22–2 record and sitting in last place in the Eastern Conference. MacLean was fired from his coaching position and was replaced by Jacques Lemaire.

On December 1, 2011, the Carolina Hurricanes, after hiring Kirk Muller as their new head coach, hired MacLean as an assistant coach. MacLean, along with fellow assistant coach Dave Lewis, was relieved of his duties on May 5, 2014.

On July 27, 2017, MacLean joined the Arizona Coyotes as an assistant coach.

On September 8, 2021, the San Jose Sharks hired MacLean as an assistant coach. He was relieved of his duties on July 1, 2022.

On July 28, 2022, MacLean was hired as an assistant coach by the New York Islanders.

Post-playing career
In addition to working as an analyst on NHL Network, MacLean most recently served as a hockey analyst for MSG Networks, including the pre- and post-game coverage for the Devils.

Awards

 * Stanley Cup (1995) New Jersey Devils - As Player
 * Stanley Cup (2003) New Jersey Devils - As Assistant Coach
 * Memorial Cup tournament All-Star Team (1983)
 * Selected to two NHL All-Star Games, 1989 and 1991
 * New Jersey Devils MVP, 1989–90

Records

 * New Jersey Devils franchise record for power play points (197)
 * New Jersey season goals leader: 1988–89 (42), 1989–90 (41), 1990–91 (45), 1993–94 (37), 1996–97 (29, tie)
 * New Jersey playoffs points leader: 1991 (8, tie), 1997 (9)
 * New Jersey playoffs goals leader: 1990 (4), 1991 (5), 1997 (4, tie)
 * New Jersey playoffs assists leader: 1997 (5)
 * San Jose Sharks playoffs points leader: 1998 (5, tie)
 * San Jose Sharks playoffs goals leader: 1998 (2, tie)

title: John MacLean (ice hockey)


text:
John Fitzalan (1246–1272)

John FitzAlan III (14 September 1246 – 18 March 1272), was an English nobleman. He was also Lord and Baron of Clun and Oswestry in the Welsh Marches.

Family
He was the son of John FitzAlan II, Earl of Arundel (1223–1267), and Maud de Verdun, daughter of Theobald le Botiller (or Boteler) and Rohese (or Rohesia) de Verdun. His paternal grandparents were John FitzAlan, Lord of Oswestry and Isabel d'Aubigny.

Marriage
Lord FitzAlan married Isabella Mortimer (died 1292), daughter of Roger Mortimer, 1st Baron Mortimer and Maud de Braose in 1260. They had one son: They had at least one daughter:
 * Richard FitzAlan, 1st Earl of Arundel.
 * Matilda (Maud) FitzAlan married firstly, Philip Burnell (died 1294); married secondly, Robert de Brus, Lord of Annandale and Earl of Carrick; married thirdly, Simon de Cricketot.

title: John Fitzalan (1246–1272)


text:
Talk:God Shuffled His Feet

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title: Talk:God Shuffled His Feet


text:
Isocitrate dehydrogenase

Isocitrate dehydrogenase (IDH) and  is an enzyme that catalyzes the oxidative decarboxylation of isocitrate, producing alpha-ketoglutarate (α-ketoglutarate) and CO2. This is a two-step process, which involves oxidation of isocitrate (a secondary alcohol) to oxalosuccinate (a ketone), followed by the decarboxylation of the carboxyl group beta to the ketone, forming alpha-ketoglutarate. In humans, IDH exists in three isoforms: IDH3 catalyzes the third step of the citric acid cycle while converting NAD+ to NADH in the mitochondria. The isoforms IDH1 and IDH2 catalyze the same reaction outside the context of the citric acid cycle and use NADP+ as a cofactor instead of NAD+. They localize to the cytosol as well as the mitochondrion and peroxisome.

Structure

The NAD-IDH is composed of 3 subunits, is allosterically regulated, and requires an integrated Mg2+ or Mn2+ ion. The closest homologue that has a known structure is the E. coli NADP-dependent IDH, which has only 2 subunits and a 13% identity and 29% similarity based on the amino acid sequences, making it dissimilar to human IDH and not suitable for close comparison. All the known NADP-IDHs are homodimers.

Most isocitrate dehydrogenases are dimers, to be specific, homodimers (two identical monomer subunits forming one dimeric unit). In comparing C. glutamicum and E. coli, monomer and dimer, respectively, both enzymes were found to "efficiently catalyze identical reactions." However, C. glutamicum was recorded as having ten times as much activity than E. coli and seven times more affinitive/specific for NADP. C. glutamicum favored NADP+ over NAD+. In terms of stability with response to temperature, both enzymes had a similar Tm or melting temperature at about 55 °C to 60 °C. However, the monomer C. glutamicum showed a more consistent stability at higher temperatures, which was expected. The dimer E. coli showed stability at a higher temperature than normal due to the interactions between the two monomeric subunits.

The structure of Mycobacterium tuberculosis (Mtb) ICDH-1 bound with NADPH and Mn(2+) bound has been solved by X-ray crystallography. It is a homodimer in which each subunit has a Rossmann fold, and a common top domain of interlocking β sheets. Mtb ICDH-1 is most structurally similar to the R132H mutant human ICDH found in CNS WHO grade 4 astrocytomas, formerly classified as glioblastomas. Similar to human R132H ICDH, Mtb ICDH-1 also catalyzes the formation of α-hydroxyglutarate.

Regulation
The IDH step of the citric acid cycle is often (but not always) an irreversible reaction due to its large negative change in free energy. It must therefore be carefully regulated to avoid depletion of isocitrate (and therefore an accumulation of alpha-ketoglutarate). The reaction is stimulated by the simple mechanisms of substrate availability (isocitrate, NAD+ or NADP+, Mg2+ / Mn2+ ), product inhibition by NADH (or NADPH outside the citric acid cycle) and alpha-ketoglutarate, and competitive feedback inhibition by ATP. A conserved ncRNA upstream of the icd gene which codes for NADP+-dependent isocitrate dehydrogenase (IDH) has been reported in bacterial genomes, due to its characteristics this ncRNA resembles previous regulatory motifs called riboswitches, icd-II ncRNA motif has been proposed as a strong candidate riboswitch.

Catalytic mechanisms
Isocitrate dehydrogenase catalyzes the chemical reactions:
 * Isocitrate + NAD+ $$\rightleftharpoons$$ 2-oxoglutarate + CO2 + NADH + H+
 * Isocitrate + NADP+ $$\rightleftharpoons$$ 2-oxoglutarate + CO2 + NADPH + H+

The overall free energy for this reaction is -8.4 kJ/mol.

Steps
Within the citric acid cycle, isocitrate, produced from the isomerization of citrate, undergoes both oxidation and decarboxylation. The enzyme isocitrate dehydrogenase (IDH) holds isocitrate within its active site using the surrounding amino acids, including arginine, tyrosine, asparagine, serine, threonine, and aspartic acid.

In the provided figure, the first box shows the overall isocitrate dehydrogenase reaction. The necessary reactants for this enzyme mechanism are isocitrate, NAD+/NADP+, and Mn2+ or Mg2+. The products of the reaction are alpha-ketoglutarate, carbon dioxide, and NADH + H+/NADPH + H+. Water molecules help to deprotonate the oxygen atoms of isocitrate.

The second box in the figure illustrates step 1 of the reaction, which is the oxidation of the alpha-carbon (C2 here, also called alpha-C). In this process, the alcohol group of the alpha-carbon is deprotonated and the resulting lone pair of electrons forms a ketone group on that carbon. NAD+/NADP+ acts as an electron-accepting cofactor and collects the resulting hydride from C2. The oxidation of the alpha carbon introduces a molecular arrangement where electrons (in the next step) will flow from the nearby carboxyl group and push the electrons of the double bonded oxygen up onto the oxygen atom itself, which collects a proton from a nearby lysine.

The third box illustrates step 2, which is the decarboxylation of oxalosuccinate. In this step, the carboxyl group oxygen is deprotonated by a nearby tyrosine, and those electrons flow down to C2. Carbon dioxide, the leaving group, detaches from the beta carbon of isocitrate (C3) and the electrons flow to the ketone oxygen attached to the alpha carbon, granting a negative charge to the associated oxygen atom and forming an alpha-beta unsaturated double bond between carbons 2 and 3.

The fourth and final box illustrates step 3, which is the saturation of the alpha-beta unsaturated double bond that formed in the previous step. The negatively charged oxygen (attached to the alpha-carbon) donates its electrons, reforming the ketone double bond and pushing another lone pair (the one that forms the double bond between the alpha and beta carbons) "off" the molecule. This lone pair, in turn, picks up a proton from the nearby tyrosine. This reaction results in the formation of alpha-ketoglutarate, NADH + H+/NADPH + H+, and CO2.

Detailed mechanism
Two aspartate amino acid residues (below left) are interacting with two adjacent water molecules (w6 and w8) in the Mn2+ isocitrate porcine IDH complex to deprotonate the alcohol off the alpha-carbon atom. The oxidation of the alpha-C also takes place in this picture where NAD+ accepts a hydride resulting in oxalosuccinate. Along with the sp3 to sp2 stereochemical change around the alpha-C, there is a ketone group that is formed from the alcohol group. The formation of this ketone double bond allows for resonance to take place as electrons coming down from the leaving carboxylate group move towards the ketone.

The decarboxylation of oxalosuccinate (below center) is a key step in the formation of alpha-ketoglutarate. In this reaction, the lone pair on the adjacent Tyrosine hydroxyl abstracts the proton off the carboxyl group. This carboxyl group is also referred to as the beta subunit in the isocitrate molecule. The deprotonation of the carboxyl group causes the lone pair of electrons to move down making carbon dioxide and separating from oxalosuccinate. The electrons continue to move towards the alpha carbon pushing the double bond electrons (making the ketone) up to abstract a proton off an adjacent lysine residue. An alpha-beta unsaturated double bond results between carbon 2 and three. As you can see in the picture, the green ion represents either Mg2+ or Mn2+, which is a cofactor necessary for this reaction to occur. The metal-ion forms a little complex through ionic interactions with the oxygen atoms on the fourth and fifth carbons (also known as the gamma subunit of isocitrate).

After the carbon dioxide is split from the oxalosuccinate in the decarboxylation step (below right), the enol will tautomerize to the keto from. The formation of the ketone double bond is started by the deprotonation of that oxygen off the alpha carbon (C#2) by the same lysine that protonated the oxygen in the first place. The lone pair of electrons moves down kicking off the lone pairs that were making the double bond. This lone pair of electrons abstracts a proton off the Tyrosine that deprotonated the carboxyl group in the decarboxylation step. The reason that we can say that the Lys and Tyr residues will be the same from the previous step is because they are helping in holding the isocitrate molecule in the active site of the enzyme. These two residues will be able to form hydrogen bonds back and forth as long as they are close enough to the substrate.

The isocitrate dehydrogenase enzyme as stated above produces alpha-ketoglutarate, carbon dioxide, and NADH + H+/NADPH + H+. There are three changes that occurred throughout the reaction. The oxidation of Carbon 2, the decarboxylation (loss of carbon dioxide) off Carbon 3, and the formation of a ketone group with a stereochemical change from sp3 to sp2.

Active site

The Isocitrate Dehydrogenase (IDH) enzyme structure in Escherichia coli was the first IDH ortholog structure to be elucidated and understood. Since then, the Escherichia coli IDH structure has been used by most researchers to make comparisons to other isocitrate dehydrogenase enzymes. There is much detailed knowledge about this bacterial enzyme, and it has been found that most isocitrate dehydrogenases are similar in structure and therefore also in function. This similarity of structure and function gives a reason to believe that the structures are conserved as well as the amino acids. Therefore, the active sites amongst most prokaryotic isocitrate dehydrogenase enzymes should be conserved as well, which is observed throughout many studies done on prokaryotic enzymes. Eukaryotic isocitrate dehydrogenase enzymes on the other hand, have not been fully discovered yet. Each dimer of IDH has two active sites. Each active site binds a NAD+/NADP+ molecule and a divalent metal ion (Mg2+,Mn2+). In general, each active site has a conserved sequence of amino acids for each specific binding site. In Desulfotalea psychrophila (DpIDH) and porcine (PcIDH) there are three substrates bound to the active site.

 * 1) Isocitrate binds within the active site to a conserved sequence of about eight amino acids through hydrogen bonds. These acids include (may vary in residue but with similar properties) tyrosine, serine, asparagine, arginine, arginine, arginine, tyrosine, and lysine. Their positions on the backbone vary but they are all within a close range (i.e. Arg131 DpIDH and Arg133 PcIDH, Tyr138 DpIDH and Tyr140 PcIDH).
 * 2) The metal ion (Mg2+, Mn2+) binds to three conserved amino acids through hydrogen bonds. These amino acids include three Aspartate residues.
 * 3) NAD+ and NADP+ bind within the active site within four regions with similar properties amongst IDH enzymes. These regions vary but are around [250–260], [280–290], [300–330], and [365–380]. Again regions vary but the proximity of regions are conserved.

Clinical significance
Specific mutations in the isocitrate dehydrogenase gene IDH1 have been found in several tumor types, notably brain tumors including astrocytoma and oligodendroglioma. Patients whose tumor had an IDH1 mutation had longer survival compared to patients whose tumor had an IDH1 wild type. Furthermore, mutations of IDH2 and IDH1 were found in up to 20% of cytogenetically normal acute myeloid leukemia (AML). These mutations are known to produce D-2-hydroxyglutarate from alpha-ketoglutarate. D-2-hydroxyglutarate accumulates to very high concentrations which inhibits the function of enzymes that are dependent on alpha-ketoglutarate. This leads to a hypermethylated state of DNA and histones, which results in different gene expression that can activate oncogenes and inactivate tumor-suppressor genes. Ultimately, this may lead to the types of cancer described above. Somatic mosaic mutations of this gene have also been found associated to Ollier disease and Maffucci syndrome. However, recent studies have also shown that D-2-hydroxyglutarate may be converted back into alpha-ketoglutarate either enzymatically or non-enzymatically. Further studies are required to fully understand the roles of IDH1 mutation (and D-2-hydroxyglutarate) in cancer. Recent research highlighted cancer-causing mutations in isocitrate dehydrogenase which may cause accumulation of the metabolite D-2-hydroxyglutarate (D-2HG). Notarangelo et al. showed that such high concentrations of D-2HG could act as a direct inhibitor of lactate dehydrogenase in mouse T cells. Inhibition of this metabolic enzyme altered glucose metabolism in the T cells and inhibited their proliferation, cytokine production, and ability to kill target cells.

Isozymes
The following is a list of human isocitrate dehydrogenase isozymes:

NADP+ dependent
Each NADP+-dependent isozyme functions as a homodimer:

NAD+ dependent
The isocitrate dehydrogenase 3 isozyme is a heterotetramer that is composed of two alpha subunits, one beta subunit, and one gamma subunit:

title: Isocitrate dehydrogenase


text:
She Who Dwells in the Secret Place of the Most High Shall Abide Under the Shadow of the Almighty

She Who Dwells in the Secret Place of the Most High Shall Abide Under the Shadow of the Almighty is a 2003 double album by Sinéad O'Connor.

It is a two-CD set. The first CD collects several rare tracks O'Connor recorded as B-sides, for soundtrack albums or in collaboration with other artists, and the second disc contains a live concert.

The album's title is a modification of Psalm 91, verse 1. This is the same psalm that gave O'Connor's first album, The Lion and the Cobra, its name.

Disc one
Disc one collects a variety of rare tracks. It includes readings of traditional Latin liturgical hymns, collaborations with Massive Attack, Asian Dub Foundation, Adrian Sherwood and Roger Eno, and covers of songs by ABBA, The B-52's, and Aretha Franklin.

 * 1) "Regina Caeli" (Traditional) – 1:03
 * 2) "O Filii et Filiæ" (Traditional) – 3:14
 * 3) "My Love I Bring" (Pablo Moses) – 3:55
 * 4) "Do Right Woman, Do Right Man" (Chips Moman, Dan Penn) – 3:55
 * 5) "Love Hurts" (Boudleaux Bryant) – 4:03
 * 6) "Ain't It a Shame" (Keith Strickland, Cindy Wilson, Ricky Wilson) – 4:31
 * 7) "Chiquitita" (Benny Andersson, Björn Ulvaeus) – 3:50
 * 8) "Brigidine Diana" (O'Connor) – 4:14
 * 9) "It's All Good" (Damien Dempsey) – 5:09
 * 10) "Love Is Ours" (O'Connor, Neil Davidge, Robert Del Naja) – 4:45
 * 11) "A Hundred Thousand Angels" (Andrew Blissett, Lucinda Mary Drayton) – 3:20
 * 12) "You Put Your Arms Around Me" (O'Connor, Rick Nowels) – 4:59
 * 13) "Emma's Song" (MacDonald, O'Connor, Adrian Sherwood) – 4:22
 * 14) "No Matter How Hard I Try" (O'Connor, David A. Stewart, Eno) – 4:24
 * 15) "Dense Water, Deeper Down" (O'Connor) – 3:34
 * 16) "This IS a Rebel Song" (O'Connor) – 3:49
 * 17) "1000 Mirrors" (Aniruddha Das, John Pandit, Steve Chandra Savale, Delbert Tailor) – 4:53
 * 18) "Big Bunch of Junkie Lies" (O'Connor) – 4:03
 * 19) "Song of Jerusalem" (Traditional) – 5:52

Disc two
Disc two is a live performance recorded at Dublin's Vicar Street Theatre in 2002. Six tracks are taken from O'Connor's 2002 album Sean-Nós Nua, and three each come from Universal Mother and O'Connor's most famous album, I Do Not Want What I Haven't Got. One song, "You Made Me the Thief of Your Heart", was recorded by O'Connor for the soundtrack to the 1993 film In the Name of the Father, and does not appear on any of O'Connor's studio albums.

 * 1) "Molly Malone" (Traditional) – 3:56
 * 2) "Óro, Sé do Bheatha 'Bhaile" (Traditional) – 3:07
 * 3) "The Singing Bird" (Traditional) – 4:25
 * 4) "My Lagan Love" (Traditional) – 5:12
 * 5) "I Am Stretched on Your Grave" (Philip King) – 4:43
 * 6) "Nothing Compares 2 U" (Prince) – 5:40
 * 7) "John, I Love You" (O'Connor) – 5:30
 * 8) "The Moorlough Shore" (Traditional) – 5:41
 * 9) "You Made Me the Thief of Your Heart" (Paul Hewson, Gavin Friday, Morris Roycroft) – 4:38
 * 10) "Paddy's Lament" (Traditional) – 5:36
 * 11) "Thank You for Hearing Me" (O'Connor) – 5:12
 * 12) "Fire on Babylon" (O'Connor) – 7:32
 * 13) "The Last Day of Our Acquaintance" (O'Connor) – 5:58