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United States Army Medical Department Center and School

MG Stephen (Steve) L Jones

The U.S. Army Medical Department Center and School, Health Readiness Center of Excellence (AMEDDC&amp running hip pack;S HRCoE) — located at Fort Sam Houston, Texas — is both a school and a “think tank”. The School — known as the Academy of Health Sciences (AHS) — serves the U.S. Army in educating and training all of its medical personnel. The Center formulates the Army Medical Department’s (AMEDD’s) organization, tactics, doctrine, and equipment.

Although its institutional lineage dates back to 1920 what tenderises meat, the present “C&S” were established by permanent order of the Surgeon General in 1991.

On 1 September 1920, the Medical Department Field Service School was established at Carlisle Barracks, Pennsylvania at the request of the Surgeon General, Major General Merritte W. Ireland. In December that same year, the Army renamed it the Medical Field Service School (MFSS).

After 25 1/2 years of operation, the school was deactivated on 15 February 1946 and its mission transferred to multiple schools located at Fort Sam Houston, Texas. The school underwent various name changes and restructuring over the years; incorporating the diverse medical functional areas of the Army Medical Department (AMEDD) along the way. One significant change was on 10 December 1972, when the Secretary of the Army, Robert F. Froehlke re-designated the school to the Academy of Health Sciences.

On 15 July 1991, the Surgeon General, Lieutenant General Frank F. Ledford, Jr., established the AMEDDC&S by permanent order 103-1. The Academy of Health Sciences (AHS) now comprises the “school” portion of the AMEDDC&S.

As a result of 2005 BRAC legislation that required the bulk of enlisted technical medical training in the Army, Air Force, and Navy to be collocated to Fort Sam Houston, Texas, much of the enlisted medical training was moved from AHS to the Medical Education and Training Campus (METC). The transition took place during 2010 and 2011. In 2015, it was designated as the US Army Health Readiness Center of Excellence (HRCoE).

The Academy of Health Sciences (AHS):

Château de Vaubadon

Vous pouvez partager vos connaissances en l’améliorant (comment ?) selon les recommandations des projets correspondants.

Le château de Vaubadon est une demeure du XVIIIe siècle du département du Calvados, inscrite au titre des Monuments historiques en 2012.

Le château de Vaubadon est situé sur le territoire de l’ancienne commune de Vaubadon, dans le département du Calvados, devenue le une commune déléguée au sein de la commune nouvelle de Balleroy-sur-Drôme.

L’édifice est édifié en 1778 plus précisément de 1739 à cette date par la famille Letellier.

Un parc est créé au XIXe siècle. Le domaine est mis en vente en 1810. Il est acquis par le général de Préval puis revendu en 1832 wholesale glass water bottles. Le nouveau propriétaire vendit 800 ha du parc.

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L’édifice est inscrit au titre des monuments historiques le 14 mars 2012 en particulier les éléments suivants : les façades et les toitures du château, le parc du château roma football shirt.

Sur les autres projets Wikimedia :

Đồng Nai Province

Đồng Nai (Vietnamese: [ɗə̂wŋm naːj] ( listen)) is a province in the Southeast region of Vietnam, located east and northeast of Ho Chi Minh City (Saigon). The largest city in Đồng Nai is Biên Hòa. Prior to Vietnamese colonization, the area was dominated by the Funan, Chenla, Khmer empire and subsequent influences until 1627. The area was known as Kâmpéâp Srâkatrey (កំពាប់ [កំពប់] ស្រកាត្រី) in Khmer.

Đồng Nai is situated in southeastern Vietnam and bordered by: Bình Thuận, Lâm Đồng, Bình Dương and Bình Phước, Bà Rịa–Vũng Tàu, and Ho Chi Minh City (Saigon). Đồng Nai province has an advanced traffic system with many backbone national roads crossing, such as: National route 1A, national route 20, National route 51, North–South railway lines; Located adjacent to the Saigon Port and Tan Son Nhat International Airport, it offers many advantages to economic activities in the area. Its location is very important for the development of the Southern economic main hub and a junction of the South Eastern and Tây Nguyên Highland.

Đồng Nai Province is based essentially on the system of lakes, dams and rivers, of which Trị An Lake with 323 km² and over 60 rivers, rivulets and canals are very favorable for the development of a number of aquatic products: raft bred fish and shrimp. The seasonal tropical forests are protected in Cát Tiên National Park, located on the north of Đồng Nai and the adjacent Vĩnh Cửu Nature Reserve; the former has been recognized internationally as a significant biosphere reserve. From the mountainous area, Đồng Nai River, Vietnam’s largest internal waterway, flows southeast through Biên Hòa City, Ho Chi Minh City, and villages along its way. This river plays an important role on supplying fresh water for the whole area.

Đồng Nai lies in the monsoon tropical zone and is affected by the north-east and south-west monsoon. It is also under the influence of Pacific Ocean tropic atmosphere between April and October. Climate is divided in two distinct seasons. The rainy season lasts from March or April to November and the dry season from December to March or April of the following year. Average temperature is between 23.9 and 29 glass bottles with lids for drinking.0 °C, much lower than standard level of the tropical regions (26-30 °C). Its annual rainfall is quite high with 1,500 – 2,700 mm.

On average, the weather is sunny for 4.0-9.5 hours a day and does not exceed 11.5 hours per day, even on the hottest and sunniest days. Total rainy days within a year are between 120 and 170 days (standard level of tropical region is 150–160 days) with total rainfall of some 1,500 – 2,750 mm. The average humidity is around 80 – 82% and humidity in the dry season is 10-12%, lower than that of the rainy season; humidity varies considerably between areas.

Đồng Nai Province’s weather with regular sunshine, rain, and high humidity, equally found in the localities, facilitates agricultural production and development of industry and cultural and tourism activities.

Đồng Nai is plentiful with forest resources, granite mines, construction stone, clay, kaolin, pozzolan, sand, gravel, etc.

Đồng Nai is one of Vietnam’s most populous provinces (ranked 5) with a population of 2,838,600 in 2014. Its population has been growing rapidly in recent years, mainly driven by migrant workers coming to the province to work in factories. Population growth was 1.95% in 2005, between 2.5% from 2008 to 2010 and 3.5% in 2011. Net migration contributed 2.2% to this figure. Đồng Nai is second only to Bình Dương Province in both population growth and net migration.

The population of Đồng Nai is primarily the dominant Kinh (Viet) ethnicity, although there are residents of the Chinese, Stieng, Mạ, Nùng, Tay, and Cham minorities.

Đồng Nai has made significant progress in upgrading its transport infrastructure, especially roads. National highways in the province have a total length of 244.5 km and have been improved and widened up to level 1 and 2 standards (National Highway No 5 and 6) or up to third grade like National Highway No 20 to Da Lat. The total roads system in the province is 3.339 kilometers long, of which almost 700 kilometers are tar roads. All communes and wards are connected to the road network.

Under scheme in the near future, highways to Bà Rịa–Vũng Tàu Province and Ho Chi Minh City, a railway connecting Biên Hòa to Vũng Tàu, upgraded provincial roads No 726 and connecting national highway No 20 and No 1 with national highway No 51 will create a complete system, promoting socioeconomic development in the province and region.

A new airport, Long Thanh International Airport, is planned for construction in Long Thanh district, Đồng Nai, approximately 40 km northeast of Ho Chi Minh City. Upon completion, it will handle international flights in place of Tan Son Nhat International Airport, which will serve domestic flights footbal jersey.

Đồng Nai is subdivided into 11 district-level sub-divisions:

They are further subdivided into 8 commune-level towns (or townlets), 136 communes, and 29 wards.

Đồng Nai is one of Vietnam’s main manufacturing centers and one of the most developed provinces.

Despite its strong focus on industrial development, Đồng Nai still has a substantial agricultural sector. Agricultural land accounts for 47% of the province’s area as of 2011, a total of 277,600ha. This is lower than in other provinces in the Southeast region, except for Ho Chi Minh City. Cereals were grown on 118,600ha in 2011, an area that has been decreasing gradually in recent years, from 139,300ha in 2005. Output of rice has however remained stable and was at 335,200t in 2011. The province also produced 305,300t of maize, making it the largest producer of maize outside the country’s mountainous regions and contributing 6.3% to the national maize output. Đồng Nai also produced 619,700t of sugar cane (3.5% of the national output), sweet potatoes and cassava.

Đồng Nai is the largest livestock producer among Vietnam’s provinces and plans to further invest in the sector. The government reserved 15,000ha for livestock farming in 2012, mostly for poultry and pigs. In 2011 there were 1.33 million pigs and 10.655 million poultry. Despite not being located along the coast, Đồng Nai produced 41,600t of fishery products in 2011. Over 90% of this was produced in 33,500ha of aquaculture farms. This makes Đồng Nai the largest aquaculture producer outside the Mekong Delta.

Đồng Nai is one of Vietnam’s main manufacturing centers. It has attracted 9.1% of FDI into Vietnam by 2011, an accumulated US$18.2 billion, the fourth largest after Ho Chi Minh City, Bà Rịa–Vũng Tàu Province and Hanoi. Industrial gross output in 2011 was VND 314 trillion, 10.6% of the national value. It has received a broad range of FDI projects, including a Bosch auto component plant, a Toshiba motor plant, a PepsiCo beverage factory, a Posco steel plant, and a Nestlé coffee factory.

As defined by a 2008 World Bank survey, the province is one of the 5 most polluted in Vietnam.

Kūh-e Moshkān

Kūh-e Moshkān (persiska: کوه مشکان) är ett berg i Iran small glass bottle. Det ligger i provinsen Fars, i den centrala delen av landet, 700 km söder om huvudstaden Teheran. Toppen på Kūh-e Moshkān är 2 871 meter över havet.

Terrängen runt Kūh-e Moshkān är kuperad norrut, men söderut är den bergig. Den högsta punkten i närheten är 2 955 meter över havet, 1,0 km norr om Kūh-e Moshkān. Runt Kūh-e Moshkān är det glesbefolkat, med 12 invånare per kvadratkilometer. Närmaste större samhälle är Meshkān, 8,6 km öster om Kūh-e Moshkān unbreakable glass water bottle. Omgivningarna runt Kūh-e Moshkān är i huvudsak ett öppet busklandskap. I trakten runt Kūh-e Moshkān finns ovanligt många namngivna berg, vattenkällor och dalar.

Ett kallt stäppklimat råder i trakten. Årsmedeltemperaturen i trakten är 19 °C. Den varmaste månaden är juli, då medeltemperaturen är 32 °C, och den kallaste är januari, med 2 °C. Genomsnittlig årsnederbörd är 223 millimeter. Den regnigaste månaden är februari, med i genomsnitt 42 mm nederbörd, och den torraste är juni, med 1 mm nederbörd.

Disabled Peoples’ International

Disabled Peoples’ International (DPI) ist eine internationale Nichtregierungsorganisation mit Sitz in Ottawa und mit regionalen Niederlassungen in Asien-Pazifik, dem Mittleren Osten eco glass water bottle, Europa, Afrika, Lateinamerika und Nordamerika und der Karibik stainless steel water bottle with stainless steel cap.

Es ist ein Netzwerk von nationalen Organisationen oder Vereinigungen von Menschen mit Behinderungen, gegründet im Jahr 1981, um die Menschenrechte von Menschen mit Behinderungen durch eine volle Teilhabe, Angleichung der Chancen und Entwicklungsmöglichkeiten zu fördern. DPI unterstützt Organisationen in über 120 Nationen bei den alltäglichen Problemen.

Die Ziele sind:

DPI hat einen Sonderstatus als Berater bei den Vereinten Nationen und arbeitet mit vielen internationalen Organisationen und Regierungen der Welt zusammen.

1992 initiierte der Verband den europäischen Protesttag zur Gleichstellung von Menschen mit Behinderungen, der seither jährlich am 5 waterproof sack. Mai begangen wird, 2011 beispielsweise unter dem Motto „Inklusion beginnt im Kopf“ aluminum water bottles safe.

Der deutsche Zweig des Verbandes ist die Interessenvertretung Selbstbestimmt Leben.

John Charles

William John Charles (født 27. desember 1931, død 21. februar 2004) var en walisisk fotballspiller, mest kjent som spiller for Leeds United og Juventus på 1950- og 1960-tallet. Mange mener han var en av de beste spillerene noensinne fra Storbritannia. Hans favorittposisjon på banen var spiss, men han kunne brukes nær sagt hvor som helst. Han ble innvalgt i Engelsk fotballs Hall of Fame i 2002.

Han fikk aldri en eneste advarsel, ikke et eneste gult kort og ble aldri utvist. Hans fotballfilosofi gikk ut på å alltid gjøre sitt beste uten å skade andre. I Italia og England ble han kalt Il Gigante Buono og The Gentle Giant – den snille kjempen.

Han startet spillerkarrieren i Swansea City som ungdom, men ble raskt oppdaget av Leeds United. Etter ni år i Leeds, ble han i 1957 solgt til Juventus i Torino i Italia for daværende overgangsrekord på 65 000 pund. På sine fem år i Juventus vant han Serie A tre ganger og den italienske cupen to ganger og i 1997 ble han av Juventus’ supportere valgt til den beste utlending som hadde spilt for klubben.

Charles vendte så tilbake til Leeds United i 1962, men fikk problemer med å omstille seg til den engelske fotballen igjen steel water container. Han dro så tilbake til Italia for å spille for AS Roma, men etter en god innledning ble han skadet og forlot landet til fordel for hjemlandet Wales og klubben Cardiff City.

John Charles ble så spillende manager for Hereford United og var det i fem år før han i 1971 gikk til Merthyr Tydfil FC, igjen som spillende manager thermos australia. Han la opp som aktiv i 1974 etter 26 år som profesjonell fotballspiller. Senere var han blant annet i Canada, der han var leder i klubben Hamilton Steelers før han flyttet til Yorkshire i England der han livnærte seg som pub-eier i mange år. Han fikk på sine eldre dager diagnosen Alzheimers sykdom.

Charles var kommandør av Order of the British Empire.

1 Kelsey · 2 Williams · 3 Hopkins · 4 Sullivan · 5 M. Charles · 6 Bowen  · 7 Medwin · 8 Hewitt · 9 J. Charles · 10 I. Allchurch · 11 C. Jones · 12 K. Jones · 13 Vearnecombe · 14 Edwards · 15 C. Baker · 16 Crowe · 17 Leek · 18 Vernon · 19 Webster · 20 Elsworthy · 21 L. Allchurch · 22 T. Baker · trener: Murphy

· · ·

…All This Time

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…All This Time è un album dal vivo del cantante britannico Sting, registrato l’11 settembre 2001. Il live racchiude il concerto privato tenuto dal cantante nella sua villa italiana (Villa Il Palagio) di fronte ad un pubblico selezionato tratto dal suo fan club. L’esibizione contiene classici di Sting solista e alcuni pezzi dei Police. L’album prende il nome dalla canzone All This Time contenuta nell’album The Soul Cages del 1991.

Con il CD è incluso un DVD video, comprendente una lista parzialmente differente di canzoni, tre tracce bonus, interviste e dietro le quinte.

Nell’intenzione di mettere insieme un concerto a casa sua davanti a pochi ospiti speciali, Sting arruolò un gruppo di musicisti per suonare insieme a lui. Gli eventi che portarono alla notte dell’esibizione sono stati filmati, e tra questi gli attentati dell’11 settembre 2001 a New York che si verificarono il giorno stesso del concerto, con il gruppo assemblato che venne reso a conoscenza della tragedia.

« Avevamo passato una settimana a provare, ci stavamo preparando ad avere una splendida, gioiosa festa quella sera, un’esibizione dal vivo homemade meat tenderizer, 200 amici. Stavamo giusto pranzando. Qualcuno disse, “è meglio che entrate e guardate la TV”, e abbiamo assistito all’orrore di ciò che era accaduto quella mattina. Io andai fuori a sedermi e decisi che non potevo cantare. Per quale motivo avrei voluto cantare quella notte? E così chiamai la band in riunione, una sorta di riunione democratica. Dissi, “Ragazzi, non penso di poter cantare stasera. Cosa dite?”. “Beh, noi – beh, dobbiamo”. All’unanimità, tutti mi dissero che l’avrebbero fatto – avrebbero suonato, perché è ciò che un musicista fa. Alcuni di loro provenivano da New York, alcuni non hanno potuto mettersi in contatto con le loro famiglie, ovviamente molto, molto stressati, hanno comunque voluto suonare. Mi dissero, “Inoltre, hai 250 persone che sono arrivate a casa tua, e tu sei responsabile nei loro confronti. Quindi devi dargli qualcosa”. Così io dissi, “Guarda, come compromesso eseguirò un’unica canzone. Farò Fragile, perché penso sia un sentimento appropriato”. »

Il calore e l’accoglienza del pubblico durante Fragile, ha poi convinto Sting ad eseguire il concerto per intero, come originariamente previsto. Il cantante ha comunque sottolineato nel documentario inserito nel DVD che il tono della serata si è rivelato molto diverso da come era stato originariamente pianificato.

Il concerto avrebbe anche dovuto essere trasmesso integralmente in diretta via Internet, ma alla fine si decise di mandare in onda solo Fragile, preceduta da un commosso e sommesso annuncio di Sting in omaggio alle vittime dell’attentato.

La performance di Desert Rose con il cantante algerino Cheb Mami è stata tagliata dalla pubblicazione finale per via delle circostanze dovute agli atti terroristici musulmani a danno degli americani.

A seguito dei tragici eventi, il concerto è stato dedicato a coloro che hanno perso la vita il giorno dell’11 settembre. All’interno del libretto del CD, sulla prima pagina, Sting ha voluto scrivere:

« This album was recorded on September 11, 2001, and is respectfully dedicated to all those who lost their lives on that day. »

« Questo album è stato registrato l’11 settembre 2001 ed è rispettosamente dedicato a tutti coloro che hanno perso la vita quel giorno. »

Subito dopo questa dedica, è stato trascritto il testo integrale di FragIle; dell’intero elenco dei brani inseriti nel CD, solo le liriche di Fragile sono state inserite nel libretto.

Tutte le canzoni sono state composte da Sting eccetto dove indicato.

È inoltre incluso un documentario dietro le quinte e alcune interviste che spiegano la realizzazione del concerto.

Dosis

En farmacología se entiende por dosis la cantidad de principio activo de un medicamento, expresado en unidades de volumen o peso por unidad de toma en función de la presentación, que se administrará de una vez. También es la cantidad de fármaco efectiva.

La sobredosis es la toma por encima de la dosis máxima tolerada. En su extremo, puede ser una dosis letal.

Los medicamentos se pueden presentar en forma de multidosis o unidosis. En la unidosis o dosis unitaria the best glass water bottle, cada unidad de medicamento es una toma y viene identificada con su lote y caducidad. A nivel hospitalario se emplea cada vez más la unidosis por ser más cómoda y evitar errores en la toma.

Se denomina dosis máxima tolerada, MTD, por sus siglas en inglés —Maximum Tolerated Dose— a la dosis más elevada de un medicamento o tratamiento que un paciente puede recibir sin causarle efectos secundarios inaceptables,​ tales como muerte o disfunción celular u orgánica o efectos que disminuyen la esperanza de vida o un retraso superior al 10 % del peso corporal respecto a los sujetos de control.​ Se suele determinar durante los ensayos clínicos, Mediante el procedimiento de aumentar las dosis gradualmente hasta que se encuentra la dosis más alta con efectos secundarios tolerables.

En Radiología y Protección Radiológica wide mouth glass water bottle, se utiliza el término dosis para la cantidad de radiación recibida por material, y más típicamente, por un ser vivo. Dependiendo del objetivo de la medida, se definen diversas magnitudes:

Mario De Prati

Mario De Prati, all’anagrafe Mario Deprati (Mortara, 11 ottobre 1928), è un ex calciatore italiano, di ruolo attaccante.

Soprannominato Mariolino, alcune fonti lo riportano come Giovanni.

Inizia la carriera nella Medese, con cui gioca nel Girone E della Serie C 1947-1948, dove, pur ottenendo il settimo posto, retrocedono in Promozione. La stagione seguente passa per 200.000 lire al Pavia, ottenendo l’undicesimo posto del Girone B della Serie C e realizzando 12 reti in 31 partite.

Le sue prestazioni nelle file della formazione pavese gli valgono l’ingaggio nell’Inter, che lo cede in prestito al Cagliari per la stagione 1949-1950, dove chiude al sesto posto del girone C della Serie C.

Nel 1950 l’Inter lo gira a novembre al Genoa, squadra con cui debutta nella Serie A 1950-1951. L’esordio in rossoblu e nella massima serie è datato 28 gennaio 1951, nella sconfitta esterna per 2-1 contro l’Atalanta. La stagione con il Grifone si concluderà con l’ultimo posto e la retrocessione in cadetteria. Nell’unica stagione disputata in Serie A, marca dodici presenze e quattro reti. Gioca la stagione seguente tra le file del Vigevano, sempre in prestito: vince il girone A della Serie C, mancando la promozione in cadetteria poiché ottiene solo il quarto posto del gironcino finale.

Torna al Pavia per disputare la Serie C 1952-1953, che vince ottenendo la promozione in cadetteria. In quella stagione realizza 17 reti, classificandosi al terzo posto della classifica cannonieri, dietro al tarantino Mario Tortul e al sanremese Bertoni. Stabilisce inoltre il record di marcature stagionali per la squadra lombarda in Serie C, battuto solo nel 2005 da Francesco Ciullo.

Nel 1953 lascia definitivamente l’Inter per passare alla Marzotto Valdagno, con cui disputa cinque stagioni in Serie B. Con il club veneto ottiene nella Serie B 1953-1954 il quinto posto, a due punti dal promosso Pro Patria reusable water bottles bpa free, piazzamento a cui contribuisce con 27 presenze e 10 reti. Nelle ultime due stagioni con il club biancoazzurro non scende mai in campo.

Nel 1958 passa al Piacenza, con cui gioca la Serie C 1958-1959 chiusa al diciannovesimo posto del girone A bottle belt; De Prati lascia la squadra in primavera, rescindendo il contratto dopo una stagione deludente. Chiude la carriera con una stagione nella Stradellina e due annate al Pavia, con cui ottiene nel 1961 una promozione in Serie D dalla Prima Categoria.

Power system simulation

Electrical power system simulation involves power system modeling and network simulation in order to analyze electrical power systems using design/offline or real-time data. Power system simulation software’s are a class of computer simulation programs that focus on the operation of electrical power systems. These types of computer programs are used in a wide range of planning and operational situations for:

Applications of power system simulation include:

These programs typically make use of mathematical optimization techniques such linear programming, quadratic programming, and mixed integer programming.

Key elements of power systems that are modeled include:

There are many power simulation software packages in commercial and non-commercial forms that range from utility-scale software to study tools

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The load-flow calculation is the most common network analysis tool for examining the undisturbed and disturbed network within the scope of operational and strategic planning.

Using network topology, transmission line parameters, transformer parameters, generator location and limits bag for cell phone, and load location and compensation, the load-flow calculation can provide voltage magnitudes and angles for all nodes and loading of network components, such as cables and transformers. With this information, compliance to operating limitations such as those stipulated by voltage ranges and maximum loads, can be examined. This is, for example, important for determining the transmission capacity of underground cables, where the influence of cable bundling on the load capability of each cable has to be taken also into account.

Due to the ability to determine losses and reactive-power allocation, load-flow calculation also supports the planning engineer in the investigation of the most economical operation mode of the network.

When changing over from single and/or multi-phase infeed low-voltage meshed networks to isolated networks, load-flow calculation is essential for operational and economical reasons. Load-flow calculation is also the basis of all further network studies, such as motor start-up or investigation of scheduled or unscheduled outages of equipment within the outage simulation.

Especially when investigating motor start-up, the load-flow calculation results give helpful hints, for example, of whether the motor can be started in spite of the voltage drop caused by the start-up current.

Short circuit analysis analyzes the power flow after a fault occurs in a power network. The faults may be three-phase short circuit, one-phase grounded, two-phase short circuit, two-phase grounded, one-phase break, two-phase break or complex faults. Results of such an analysis may help determine the following:

The goal of transient stability simulation of power systems is to analyse the stability of a power system in a from sub-second to several tens of seconds. Stability in this aspect is the ability of the system to quickly return to a stable operating condition after being exposed to a disturbance such as for example a tree falling over an overhead line resulting in the automatic disconnection of that line by its protection systems. In engineering terms, a power system is deemed stable if the substation voltage levels and the rotational speeds of motors and generators return to their normal values in a quick and continuous manner.

Models typically use the following inputs:

The acceptable amount of time it takes grid voltages return to their intended levels is dependent on the magnitude of voltage disturbance, and the most common standard is specified by the CBEMA curve in Figure. 1

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. This curve informs both electronic equipment design and grid stability data reporting.

The problem of unit commitment involves finding the least-cost dispatch of available generation resources to meet the electrical load.

Generating resources can include a wide range of types:

The key decision variables that are decided by the computer program are:

The latter decisions are binary {0,1}, which means that the mathematical problem is not continuous.

In addition, generating plants are subject to a number of complex technical constraints, including:

These constraints have many different variants; all this gives rise to a large class of mathematical optimization problems kiwi meat tenderizer.

Electricity flows through an AC network according to Kirchhoff’s Laws. Transmission lines are subject to thermal limits (simple megawatt limits on flow), as well as voltage and electrical stability constraints.

The simulator must calculate the flows in the AC network that result from any given combination of unit commitment and generator megawatt dispatch, and ensure that AC line flows are within both the thermal limits and the voltage and stability constraints. This may include contingencies such as the loss of any one transmission or generation element – a so-called security-constrained optimal power flow (SCOPF), and if the unit commitment is optimized inside this framework we have a security-constrained unit commitment (SCUC).

In optimal power flow (OPF) the generalised scalar objective to be minimised is given by:

where u is a set of the control variables, x is a set of independent variables, and the subscript 0 indicates that the variable refers to the pre-contingency power system.

The SCOPF is bound by equality and inequality constraint limits. The equality constraint limits are given by the pre and post contingency power flow equations, where k refers to the kth contingency case:

The equipment and operating limits are given by the following inequalities:

The objective function in OPF can take on different forms relating to active or reactive power quantities that we wish to either minimise or maximise. For example we may wish to minimise transmission losses or minimise real power generation costs on a power network.

Other power flow solution methods like stochastic optimization incorporate the uncertainty found in modeling power systems by using the probability distributions of certain variables whose exact values are not known. When uncertainties in the constraints are present, such as for dynamic line ratings, chance constrained optimization can be used where the probability of violating a constraint is limited to a certain value. Another technique to model variability is the Monte Carlo method, in which different combinations of inputs and resulting outputs are considered based on the probability of their occurrence in the real world. This method can be applied to simulations for system security and unit commitment risk, and it is increasingly being used to model probabilistic load flow with renewable and/or distributed generation.

The cost of producing a megawatt of electrical energy is a function of:

In addition to this, generating plant incur fixed costs including:

Assuming perfect competition, the market-based price of electricity would be based purely on the cost of producing the next megawatt of power, the so-called short-run marginal cost (SRMC). This price however might not be sufficient to cover the fixed costs of generation, and thus power market prices rarely show purely SRMC pricing. In most established power markets, generators are free to offer their generation capacity at prices of their choosing. Competition and use of financial contracts keeps these prices close to SRMC, but inevitably offers price above SRMC do occur (for example during the California energy crisis of 2001).

In the context of power system simulation, a number of techniques have been applied to simulate imperfect competition in electrical power markets:

Various heuristics have also been applied to this problem. The aim is to provide realistic forecasts of power market prices, given the forecast supply-demand situation.

Power system long-term optimization focuses on optimizing the multi-year expansion and retirement plan for generation, transmission, and distribution facilities. The optimization problem will typically consider the long term investment cash flow and a simplified version of OPF / UC (Unit commitment), to make sure the power system operates in a secure and economic way. This area can be categorized as: