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A smooth method for the finite minimax problem 总被引:2,自引:0,他引:2
We consider unconstrained minimax problems where the objective function is the maximum of a finite number of smooth functions. We prove that, under usual assumptions, it is possible to construct a continuously differentiable function, whose minimizers yield the minimizers of the max function and the corresponding minimum values. On this basis, we can define implementable algorithms for the solution of the minimax problem, which are globally convergent at a superlinear convergence rate. Preliminary numerical results are reported.This research was partially supported by the National Research Program on Metodi di ottimizzazione per le decisioni, Ministero dell'Università e della Ricerca Scientifica e Tecnologica, Italy. 相似文献
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Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garbincius PH Garren L Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,71(6):827-830
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Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torreta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(14):2058-2061
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Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Torretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(10):1381-1384
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Frabetti PL Cheung HW Cumalat JP Dallapiccola C Ginkel JF Greene SV Johns WE Nehring MS Butler JN Cihangir S Gaines I Garren L Garbincius PH Gourlay SA Harding DJ Kasper P Kreymer A Lebrun P Shukla S Bianco S Fabbri FL Sarwar S Zallo A Culbertson R Gardner RW Greene R Wiss J Alimonti G Bellini G Caccianiga B Cinquini L Di Corato M Giammarchi M Inzani P Leveraro F Malvezzi S Menasce D Meroni E Moroni L Pedrini D Perasso L Sala A Sala S Toretta D Vittone M Buchholz D Claes D Gobbi B O'Reilly B 《Physical review letters》1993,70(12):1755-1758
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Photodegradation of Polychlorinated Dibenzo-p-dioxins in Liquid Samples by Near UV Light Irradiation
Photodegradation of 1,2,3,4-tetrachlorodibenzo-p-dioxin (1,2,3,4-TCDD) in hexane solution was studied under controlled near-UV light exposure in the spectral region from 325 to 269 nm. GC-MS was used to detect the amount of unreacted dioxin and to characterize the relevant degradation products. Irradiation experiments carried out at a constant light energy (700 mJ) showed that the percentage of 1,2,3,4-TCDD left in the solution after irradiation changed from about 55 to 75%, with a minimum of 55% at 310 nm. Further irradiation experiments carried out at two wavelengths, namely 310 and 269 nm, and light energy ranging from 0 to 4000 mJ, showed that the photodegradation reaction of the TCDD always followed a pseudo-first-order kinetic, with a rate constant of 8 × 10−4and 5 × 10−4mJ−1, respectively. These experiments also showed that trichloro- and dichloro-dibenzo-p-dioxins were produced with less than 15% of the initial quantity of TCDD, leading to the conclusion that the dechlorination process is a minor photolysis pathway. 相似文献