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Input-output coefficient matrix

Constraints (5.13) and (5.14) represent the material balance that governs the operation of the petrochemical system. The variable x 1 represents the annual level of production of process m Mpa where ttcpm is the input-output coefficient matrix of material cp in process m Mpel. The petrochemical network receives its feed from potentially three main sources. These are, (i) refinery intermediate streams of an intermediate product cir RPI, (ii) refinery final products Ff ri of a final product cfr RPF, and (iii) non-refinery streams Fn px of a chemical cp NRF. For a given subset of chemicals cp CP, the proposed model selects the feed types, quantity and network configuration based on the final chemical and petrochemical lower and upper product demand Dpet and DPet for each cp CFP, respectively. In constraint (5.15), defining a binary variable yproc et for each process m Mpet is required for the process selection requirement as yproc et will equal 1 only if process m is selected or zero otherwise. Furthermore, if only process m is selected, its production level must be at least equal to the process minimum economic capacity B m for each m Mpet, where Ku is a valid upper... [Pg.98]

In order to perform these steps with a minimum of input-output operations one has to keep all matrices A in high-speed memory. Furthermore, the coupling coefficients should be ordered according to the label i. Then, if all for a given i can be kept in core, a single read of these coefficients is sufficient to calculate the Gj) for all i j. For applications with up to 8-10 active orbitals, the memory requirement to perform these steps is not exceedingly large, in particular if molecular symmetry can be used. Note that the crucial step is the matrix multiplication in Eq. (234) and this can be perfectly vectorized. [Pg.56]

The intent here is to give only a brief summary of the methodology by which the studies were carried out. Briefly, input-output analysis was the basic tool used. The economy was modeled as a steady state, full employment economy for 1975 and 1978 for the corrosion and fracture studies respectively. The economy was broken down into 130 sectors for the corrosion study and 150 sectors for fracture study. In both cases, capital equipment was treated as an input into production rather than a part of final demand as normally done. Having established the steady state for the chosen year for the world as it is (World I), steady state World II (corrosion or fracture free world) and World III (best practical world) were established. Final demand and the coefficients in the transactions matrix and the flow and stock capital matrices were changed as appropriate. In the case of the flow matrix, changes in the coefficients by column were collected in a special "social savings row. This precluded the necessity to renormalize the coefficients and gave a convenient way for... [Pg.388]

Changes in technology can often be incorporated into an input-output analysis by estimating new direct coefficients for a specific industry or industries. Once a new D matrix has been estimated, the T matrix can be found by inverting I - D. However, often it is inconvenient or too expensive to perform the inversion. This problem considers two ways in which changes in the T matrix can be estimated with a new D matrix. [Pg.158]

Note that the starting choice for the coefficients of equation 6.2 are based on the assumption there are no two-electron terms, i.e. the input density matrix, cells E 11 to F 12 are set to zero from the link to canonical G 2 to scf G 3. Remember, too, that as in the case of the ground state of helium there is only one doubly-occupied orbital, so the output density matrix is comprised of the coefficients of the 1CT(,+ orbital only. [Pg.214]

Thus, in that example the linear system is ill-conditioned (its coefficient matrix A has a large condition number) and is sensitive to the input errors even if the computation is performed with infinite precision. Systems like Eq. (1) are not very sensitive to the input errors if the condition number of A is not large (then the system is called well conditioned). The latter fact follows from the next perturbation theorem, which bounds the output errors depending on the perturbation of inputs (on the input error) and on cond(A). [Pg.187]

A represents the national technical coefficient matrix and the element ay in A represents the input of sub-sector i when sub-sector j is a unit output of product or service. [Pg.767]

Some input-output behaviour can be included in the UPSR by applying it to closed-loop systems. The coefficient matrix A of closed-loop systems will include some of the input-output structure from the open-loop B, C, and D matrices. [Pg.139]

The UPSR is a measure of the interaction between states only, although it can be applied to systems with different degrees of connection between components — for example open-loop and closed-loop systems. It is calculated using only the state coefficient matrix A, and makes no use of the input-output matrices B, C, and D. [Pg.144]

Here p is a row vector of money prices, A is the matrix of input coefficients, h is a column vector of consumption coefficients and 1 is a row vector of labour coefficients. In this price equation all inputs are calculated using money prices the money value of capital good inputs, for example, is represented by the term pA. The equilibrium reproduction condition is therefore easily established since the same price vector is applied to inputs and outputs. [Pg.95]

The intermediate material balances within and across the refineries can be expressed as shown in constraint (3.2). The coefficient acr,dr,i,P can assume either a positive sign if it is an input to a unit or a negative sign if it is an output from a unit. The multirefinery integration matrix dr y accounts for all possible alternatives of connecting intermediate streams dr CIR of crude cr CR from refinery ie I to process p P in plant i i. Variable xiRef. , represents the... [Pg.62]

On input the array A contains the decomposed matrix as given by the module M14, and the right-hand side coefficients are placed into the vector X. On output, this vector will store the solution. There is nothing to go wrong in backsubstitution if the previous decomposition was successful, and hence we dropped the error flag. [Pg.32]

In this array form, these equations can easily be solved on a computer. But, for many cases, the number of sieves used in analysis is relatively small, often less than five, making manual manipulation also possible. In addition, the coefficients of the T J(f) T matrix can be determined for a mill if the input and output size distribution on a mass basis is known [21], In addition to its usefulness in batch mill simulation, this equation plays a role in the description of continuous grinding as we will see in the next section. [Pg.111]

FIGURE 6.29 Schematic view of a CPG neural network trained with vector pairs. The input vector consists of ten countrates for major elements in rock samples, whereas the output vector contains the interelement coefficients p for all major elements. After training, the network is able to predict the interelement coefficients for the given sample matrix. [Pg.218]

The dollar flow matrix in Tables 4.2 and 4.4a can be normalized to yield a table of coefficients that represents the fractions of a dollar required by a sector to produce a dollar of output. This is done as follows dividing any element Xkj in the use table by the output of a sector gives the dollar input from industry k required for 1 output from industry j (6). This is defined as the direct coefficient ... [Pg.142]

Economic lO analysis accounts for direct (within the sector) and indirect (within the rest of the economy) inputs to produce a product or service by using lO matrices of a national economy. Each sector represents a row or a column in the lO matrix. The rows and the columns are normalized to add up to one. When selecting a coluum (industrial sector P) the coefficients in each row would tell how much input from each sector is needed to produce 1 worth of output in industry P. For example, an lO matrix might indicate that producing one dollar worth of steel requires 15 cents worth of coal and 10 cents of iron ore. A row of matrix specifies to which sectors the steel industry sells the product. For example, steel might sell 0.13 to the automobile industry and 0.06 to the truck industry of every dollar of revenue. [Pg.103]

A neural network contains input units, layers of neurons, and an output. Each neuron carries out arithmetic operations on its input to produce an output signal. The type of arithmetic operation is defined by the user often it is sigmoidal and restricted to values between 0 and 1. The input to a QSAR neural network is the matrix of descriptor values for each compound. One input unit represents the properties of one compound, which is one row of the matrix. In the first layer, each neuron usually represents one molecular descriptor, corresponding to one column of the matrix. However, if the input data have internal correlations, the network is set up with a reduced number of neurons (such as the number of significant principal components). The output signal from a neuron has a value that describes the relationship between all input signals and the property represented by that neuron. In multiple regression terms, this is the coefficient of the property. Some advocate... [Pg.193]


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See also in sourсe #XX -- [ Pg.98 ]

See also in sourсe #XX -- [ Pg.98 ]




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Coefficient matrix

Coefficient, input-output

Input matrix

Input/output

Output matrix

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