TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - Insensitive bounds for the moments of the sojourn times in $M/GI$ systems under state-dependent processor sharing JF - Adv. Appl. Probab. Y1 - 2010 VL - 42 SP - 246 EP - 267 ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - Individual overflow and freed carried traffics for a link with trunk reservation JF - Telecommunication Syst. Y1 - 2005 VL - 29 SP - 283 EP - 308 ER - TY - CHAP A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - On the computation of the probability of a system failure T2 - Proc. ESREL’99 10th European Conf. on Safety and Reliability, G.I. Schuëller, P. Kafka (eds.), Balkema Rotterdam Y1 - 1999 SP - 457 EP - 461 CY - München-Garching ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - Approximation for overflow moments of a multiservice link with trunk reservation JF - Perform. Eval. Y1 - 2001 VL - 43 SP - 259 EP - 268 ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - On the $M(n)/M(n)/s$ queue with impatient calls JF - Perform. Eval. Y1 - 1999 VL - 35 SP - 1 EP - 18 ER - TY - GEN A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - Workload and busy period for M/GI/1 with a general impatience mechanism N2 - The paper deals with the workload and busy period for the M/GI/1 system under FCFS discipline, where the customers may become impatient during their waiting for service with generally distributed maximal waiting times and also during their service with generally distributed maximal service times depending on the time waited for service. This general impatience mechanism, originally introduced by Kovalenko (1961) and considered by Daley (1965), too, covers the special cases of impatience on waiting times as well as impatience on sojourn times, for which Boxma et al. (2010), (2011) gave new results and outlined special cases recently. Our unified approach bases on the vector process of workload and busy time. Explicit representations for the LSTs of workload and busy period are given in case of phase-type distributed impatience. T3 - ZIB-Report - 11-43 KW - impatient customers KW - workload KW - busy period KW - waiting time dependent service Y1 - 2011 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-14304 SN - 1438-0064 ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - A note on the stability of the many-queue head-of-the-line processor-sharing system with permanent customers JF - Queueing Syst. Y1 - 1999 VL - 32 SP - 363 EP - 381 ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - On a two-queue priority system with impatience and its application to a call center JF - Methodol. Comput. Appl. Probab. Y1 - 1999 VL - 1 SP - 191 EP - 210 ER - TY - JOUR A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - On the distribution of the number of packets in the fluid flow approximation of packet arrival streams JF - Queueing Syst. Y1 - 1994 VL - 17 SP - 275 EP - 315 ER - TY - GEN A1 - Brandt, Andreas A1 - Brandt, Manfred T1 - Approximations for the second moments of sojourn times in M/GI systems under state-dependent processor sharing N2 - We consider a system with Poisson arrivals and general service times, where the requests are served according to the State-Dependent Processor Sharing (SDPS) discipline (Cohen's generalized processor sharing discipline), where each request receives a service capacity which depends on the actual number of requests in the system. For this system, denoted by $M/GI/SDPS$, we derive approximations for the squared coefficients of variation of the conditional sojourn time of a request given its service time and of the unconditional sojourn time by means of two-moment fittings of the service times. The approximations are given in terms of the squared coefficients of variation of the conditional and unconditional sojourn time in related $M/D/SDPS$ and $M/M/SDPS$ systems, respectively. The numerical results presented for $M/GI/m-PS$ systems illustrate that the proposed approximations work well. T3 - ZIB-Report - 09-25 KW - state-dependent processor sharing KW - M/GI/m-PS KW - sojourn time KW - moments KW - approximations Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0297-zib-11414 SN - 1438-0064 ER -