Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Simplex algorithm" wg kryterium: Temat


Wyświetlanie 1-2 z 2
Tytuł:
A linear programming based analysis of the CP-rank of completely positive matrices
Autorzy:
Li, Y.
Kummert, A.
Frommer, A.
Powiązania:
https://bibliotekanauki.pl/articles/907323.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
macierz pozytywna
programowanie liniowe
algorytm Simplex
completely positive matrices
cp-rank
linear programming
simplex algorithm
basic feasible solution
pivot process
Opis:
A real matrix A is said to be completely positive (CP) if it can be decomposed as A= B BT, where the real matrix B has exclusively non-negative entries. Let k be the rank of A and Phik the least possible number of columns of the matrix B, the so-called completely positive rank (cp-rank) of A. The present work is devoted to a study of a general upper bound for the cp-rank of an arbitrary completely positive matrix A and its dependence on the ordinary rank k. This general upper bound of the cp-rank has been proved to be at most k(k + 1)/2. In a recent pioneering work of Barioli and Berman it was slightly reduced by one, which means that Phik \leq k(k + 1)/2-1 holds for k \geq 2. An alternative constructive proof of the same result is given in the present paper based on the properties of the simplex algorithm known from linear programming. Our proof illuminates complete positivity from a different point of view. Discussions concerning dual cones are not needed here. In addition to that, the proof is of constructive nature, i.e. starting from an arbitrary decomposition A= B1 B1T (B1\geq 0) a new decomposition A= B2 B2T (B2\geq 0) can be generated in a constructive manner, where the number of column vectors of B2 does not exceed k(k + 1)/2-1. This algorithm is based mainly on the well-known techniques stemming from linear programming, where the pivot step of the simplex algorithm plays a key role.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2004, 14, 1; 25-31
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Zastosowanie programowania liniowego do optymalizacji zrywki drewna w trzebieżach
Application of the linear programming to optimizing wood extraction in thinnings
Autorzy:
Jabłoński, K.
Stempski, W.
Powiązania:
https://bibliotekanauki.pl/articles/989674.pdf
Data publikacji:
2016
Wydawca:
Polskie Towarzystwo Leśne
Tematy:
lesnictwo
pozyskiwanie drewna
trzebieze
zrywka drewna
skladnice drewna
lokalizacja
optymalizacja
programowanie liniowe
linear programming
simplex algorithm
wood extraction
Opis:
Improvement cuttings conducted simultaneously on a few closely located areas, often face problems about how to prepare places that would serve as temporary landings for the harvested wood. This results from insufficient wood storing space in the forest and limited accessibility of the road network to wood hauling trucks, and leads to solutions, suggesting where small landings at tree−stand edge must be established, often in places rather distant form the thinning plots. When the wood is harvested on several thinning plots and should be transported to several small landings, a problem appears, where (i.e. to which landing) should the wood from a particular thinning plot be sent. The paper presents a model to solve this problem using the simplex algorithm, which is used in linear programming, a method applied in operations research. The wood was sourced from 15 thinning plots and 11 wood landings were located. In the model, the objective function presented total transportation work, to be spent on the wood extraction. The objective function was minimized. The problem was set up on the Excel spreadsheet and then resolved with the solver application. The model enabled to direct the harvested wood from different thinning plots to different landings in an optimal way. The results enabled to design the optimal wood extraction routes and to determine the allowable changes in the amounts of wood harvested from each thinning plot, which would not change the optimal solution. The model enabled also to calculate the minimum amount of transportation work, which would be spent during the optimized transportation of wood form particular thinning plots to particular wood landings.
Źródło:
Sylwan; 2016, 160, 01; 3-10
0039-7660
Pojawia się w:
Sylwan
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-2 z 2

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies