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State-space representation

In control engineering, a state-space representation is a mathematical model of a physical system as a set of input and state variables related by first-order differential equations or difference equations. State variables are variables whose values evolve through time in a way that depends on the values they have at any given time and depends on the externally imposed values of input variables. Output variables’ values depend on the values of the state variables; the "state space" is the Euclidean space. The state of the system can be represented as a vector within that space. To abstract from the number of inputs and states, these variables are expressed as vectors. Additionally, if the dynamical system is linear, time-invariant, finite-dimensional the differential and algebraic equations may be written in matrix form; the state-space method is characterized by significant algebraization of general system theory, which makes it possible to use Kronecker vector-matrix structures. The capacity of these structures can be efficiently applied to research systems with modulation or without it.

The state-space representation provides a convenient and compact way to model and analyze systems with multiple inputs and outputs. With p inputs and q outputs, we would otherwise have to write down q × p Laplace transforms to encode all the information about a system. Unlike the frequency domain approach, the use of the state-space representation is not limited to systems with linear components and zero initial conditions; the state-space model is used in many different areas. In econometrics, the state-space model can be used for forecasting stock prices and numerous other variables; the internal state variables are the smallest possible subset of system variables that can represent the entire state of the system at any given time. The minimum number of state variables required to represent a given system, n, is equal to the order of the system's defining differential equation, but not necessarily. If the system is represented in transfer function form, the minimum number of state variables is equal to the order of the transfer function's denominator after it has been reduced to a proper fraction.

It is important to understand that converting a state-space realization to a transfer function form may lose some internal information about the system, may provide a description of a system, stable, when the state-space realization is unstable at certain points. In electric circuits, the number of state variables is though not always, the same as the number of energy storage elements in the circuit such as capacitors and inductors; the state variables defined must be linearly independent, i.e. no state variable can be written as a linear combination of the other state variables or the system will not be able to be solved. The most general state-space representation of a linear system with p inputs, q outputs and n state variables is written in the following form: x ˙ = A x + B u y = C x + D u where: x is called the "state vector", x ∈ R n.

Quanto รจ bello lu murire acciso

Quanto è bello lu murire acciso known as The Expedition and How Wonderful to Die Assassinated, is a 1976 Italian historical drama film directed by Ennio Lorenzini. It depicts the failed expedition organized by Carlo Pisacane in 1857 to provoke a rising in the Kingdom of the Two Sicilies. For this film Lorenzini won the Nastro d'Argento for Best New Director and a special David di Donatello. Giulio Brogi as Major De Liguoro Stefano Satta Flores as Carlo Pisacane Angela Goodwin as Enrichetta Bruno Corazzari as'Ntoni Alessandro Haber as Nicotera List of Italian films of 1976 Quanto è bello lu murire acciso on IMDb

Ion transport number

Ion transport number called the transference number, is the fraction of the total electrical current carried in an electrolyte by a given ionic species i, t i = I i I t o t Differences in transport number arise from differences in electrical mobility. For example, in an aqueous solution of sodium chloride, less than half of the current is carried by the positively charged sodium ions and more than half is carried by the negatively charged chloride ions because the chloride ions are able to move faster, i.e. chloride ions have higher mobility than sodium ions. The sum of the transport numbers for all of the ions in solution always equals unity; the concept and measurement of transport number were introduced by Johann Wilhelm Hittorf in the year 1853. Liquid junction potential can arise from ions in a solution having different ion transport numbers. At zero concentration, the limiting ion transport numbers may be expressed in terms of the limiting molar conductivities of the cation and electrolyte: t + = ν + ⋅ λ 0 + Λ 0 and t − = ν − ⋅ λ 0 − Λ 0,where ν + and ν − are the numbers of cations and anions per formula unit of electrolyte.

In practice the molar ionic conductivities are calculated from the measured ion transport numbers and the total molar conductivity. For the cation λ 0 + = t + ⋅ Λ 0 ν +, for the anion; the sum of the cation and anion transport numbers equals 1. There are two experimental techniques for the determination of transport numbers; the Hittorf method is based on measurements of ion concentration changes near the electrodes. The moving boundary method involves measuring the speed of displacement of the boundary between two solutions due to an electric current. In the Hittorf method, electrolysis is carried out in a cell with three compartments: anode and cathode. Measurement of the concentration changes in the anode and cathode compartments determines the transport numbers; the exact relationship depends on the nature of the reactions at the two electrodes. For the electrolysis of aqueous copper sulfate as an example, with Cu2+ and SO2−4 ions, the cathode reaction is the reduction Cu2+ + 2 e− → Cu and the anode reaction is the corresponding oxidation of Cu to Cu2+.

At the cathode, the passage of Q coulombs of electricity leads to the reduction of Q / 2 F moles of Cu2+, where F is the Faraday constant. Since the Cu2+ ions carry a fraction t + of the current, the quantity of Cu2+ flowing into the cathode compartment is t + moles, so there is a net decrease of Cu2+ in the cathode compartment equal to = t −; this decrease may be measured by chemical analysis. Analysis of the anode compartment gives a second pair of values as a check, while there should be no change of concentrations in the central compartment unless diffusion of solutes has led to significant mixing during the time of the experiment and invalidated the results; this method was developed by British physicists Oliver Lodge in 1886 and William Cecil Dampier in 1893. It depends on the movement of the boundary between two adjacent electrolytes under the influence of an electric field. If a colored solution is used and the interface stays reasonably sharp, the speed of the moving boundary can be measured and used to determine the ion transference numbers.

The cation of the indicator electrolyte should not move faster than the cation whose transport number is to be determined, it should have same anion as the principle electrolyte. Besides the principal electrolyte is kept light. CdCl2 serves best because Cd2+ is less mobile than H+ and Cl− is common to both CdCl2 and the principal electrolyte HCl. For example, the transport numbers of hydrochloric acid may be determined by electrolysis between a cadmium anode and an Ag-AgCl cathode; the anode reaction is Cd → Cd2+ + 2 e− so that a cadmium chloride solution is formed near the anode and moves toward the cathode during the experiment. An acid-base indicator such as bromophenol blue is added to make visi

Black Out (2012 film)

Black Out is a 2012 Dutch crime action comedy film. Jos Vreeswijk is a former criminal who wakes up one day before his wedding to find a murdered corpse beside him, no recollection of the night before. Raymond Thiry as Jos Vreeswijk Kim van Kooten as Caroline Bas Keijzer as Bobbie Renée Fokker as Coca Inez Edmond Classen as Charles Katja Schuurman as Charity Birgit Schuurman as Petra Willie Wartaal as Wally Kempi as Björn Simon Armstrong as Vlad Ursul de Geer as Rudolf Alex van Warmerdam as André Marwan Kenzari as Youssef Robert de Hoog as Gianni Horace Cohen as Rex Semmy Schilt as Abel Black Out holds an average rating of 40% at Rotten Tomatoes. Rembrandt Awards 2013 Nominee - Best Film Rembrandt Awards 2013 Nominee - Best Actor, Raymond Thiry Netherlands Film Festival Golden Calf 2013 Nominee - Best Supporting Actor, Bas Keijzer Netherlands Film Festival Golden Calf 2013 Nominee - Best Cinematography, Jeroen de Bruin Official website Black Out on IMDb

Eduardo Guardia

Eduardo Refinetti Guardia is a Brazilian economist and Brazil's former Finance Minister. Guardia was born in Brazil, he holds a PhD in Economics from the Economic Research Institute of the Faculty of Economics and Accounting at the University of São Paulo. He began his career as a professor, working in the Department of Economics of the Faculty of Economics, Administration and Actuarial of the Pontifical Catholic University of São Paulo. Between 1990 and 2000, he was Secretary of the Treasury of the Government of the State of São Paulo, he served as head of the Economic Advisor to the Assistant Secretary of the Treasury Department, Advisor to the Secretary of Planning and Researcher of the Fiscal Area of the Institute of Economy of the Public Sector of the Foundation for Administrative Development of São Paulo. In early 2002, he was appointed deputy secretary of the National Treasury and in May of that year he was appointed Secretary of the National Treasury. At the same time, he served as Deputy Secretary of Economic Policy of the Ministry of Finance, Assistant Secretary of the Secretariat of Economic Policy and Advisor to the Minister of Planning.

He was the product executive director of FBovespa. Between 2010 and 2013, he was executive-financial director at the institution. In June 2016, the former finance minister, Henrique Meirelles, appointed Eduardo Guardia as the executive secretary of the Treasury, replacing Tarcisio Gordoy. In April 2018, Henrique Meirelles left the post of Minister of Finance and Eduardo Guardia was appointed as his replacement. Guardia, as the new Finance Minister, has the challenge of leading the economy in an adverse economic scenario, where the Brazilian economy is still recovering from the long recession and a situation of fiscal restraint due to the public spending ceiling. In addition, he will have to draft the proposal for 2019 of the Budget Guidelines Law, as well as the proposed annual budget for next year. In the former position of Guardia, will assume Ana Paula Vescovi, secretary of the National Treasury. Guardia is known in the political arena for its rigidity in controlling expenditure and in fiscal adjustment policies.

He is recognized for his technical profile and his serious conduct, despite the lack of political influence. Throughout his experience in the federal government, Eduardo Guardia has sometimes clashed with other leaders and politicians, for example, in negotiations on Refis and requests for funds from governors, he received the nickname "Mr. No" during the Temer government, which motivated his "dismissal" by politicians from his own cabinet; the economist has expressed reservations about the current inflation rate, which has remained at low levels month by month, in which he said in a report that "there is no point in low inflation if you do not have a job." Ministry of Finance of Brazil

Mountain madtom

The mountain madtom is a North American species of temperate freshwater fish belonging to the Noturus genus of the family Ictaluridae. The species was first described to the United States National Museum by Professors Jordan and Gilbert in the Big Pigeon River; the mountain madtom has a body, characterized as being robust, by the toxic sting, associated with their pectoral and dorsal spines. The Pigeon River Recovery Project is working to try to restore the mountain madtom population, lost in fisheries. Aside from the Pigeon River Recovery Project, there is little management being applied to this species, it is listed on the threatened species list for the state of Tennessee; the mountain madtom has a broad distribution. Its native range includes larger streams of the Mississippi River drainage for the Little River system of southeastern Oklahoma northeastward. East of the Mississippi it appears through the Ohio drainage to western Pennsylvania. In the south-east it occurs in the Tennessee drainages.

In the Tennessee and Green systems it is confined to the Highland Rim. It is found in the North Fork Holston and Powell rivers; the mountain madtom is restricted to ridge and valley areas. In the Ohio river basin the mountain madtom and the northern madtom occur in similar environments but not together, it is not found on the Cumberland Plateau or the high reaches on the Blue Ridge mountain streams, due to large boulders found in the streams that lack vegetation. It is not found in glaciated regions, nor is it found with any other madtom species except the pygmy madtom, it has been reported to have been seen with stonecat madtoms in Ohio. The mountain madtom is found in fast-flowing clear riffles that are shallow headwater streams; because the mountain madtom is sensitive to siltation it is not found where there is sandy substrate. Human actions, like logging, that cause siltation in streams degridate local populations, it likes an intermediate sized cobble substrate. In Pennsylvania it has been noted to be found in areas.

Mountain madtoms are found in streams with limestone substrate that would affect the pH of the stream. Its diet is mature aquatic insects. Out of 287 stomachs viewed. Based on its diet, it competes with Etheostoma blennioides, E. rfilineatum, Cottus caroline. In all cases the mountain madtom is a nocturnal feeder and hides under large flat rocks during the day time; the entire genus Noturus has pectoral spines, some of which are serrated, some have a venomous sting, some have both. The mountain madtom has both and these serve as an anti-predatory function, not to catch prey as thought. Human actions such as dam building can hurt mountain madtoms. Juvenile mountain madtoms are 20-30mm in length usually. Adult mountain madtoms range from 75 -- the life span averages 4 -- 5 years, it is uncertain. One study located a nest and eggs were collected. In the study the nest was found in a moderately flowing stream, in a clean swept gravel substrate under a rock, 20m above a riffle. A male mountain madtom was seen guarding the nest.

The estimated clutch size is 55-115 eggs per female Relative to other fish the mountain madtom has a small clutch size because they do provide a lot of parental care to the young. The breeding season was determined to be June–July, based on the time the nest was found and how developed the eggs were. Human activity that puts silt in the streams can cause the eggs to suffocate, detrimental to the population; the ideal temperature for the eggs to hatch is 24 C. In Tennessee the mountain madtom is listed as threatened. Nationally it is listed as secure. There is no specific management in effect for the mountain madtom. There is, The Pigeon River Recovery Project; this project has reintroduced many species of darters and the mountain madtom to the Pigeon River. At one time there was a mill that pumped waste into the Pigeon River that killed all the organisms downstream of the mill; because of the secrecy of the mountain madtom, the exact causes of its decline are not known. However, since it is sensitive to silt, poor logging practices at the turn of the century are believed to have been detrimental to the population.

The mountain madtom is not a sport fish or pan fish and is not favored by fishermen, except for biologists doing research, so overfishing is not a problem. Nothing has been noted to prey on the mountain madtom, due to its venomous sting and spines, so predation is not a problem for it either