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971.
An approach to intermittent systems based on renewal processes is reviewed. The Waiting Times (WTs) between events are the
main variables of interest in intermittent systems. A crucial role is played by the class of critical events, characterized by Non-Poisson statistics and non-exponential WT distribution. A particular important case is given by WT
distributions with power tail. Critical events play a crucial role in the behavior of a property known as Renewal Aging. Focusing
on the role of critical events, the relation between superstatistics and non-homogeneous Poisson processes is discussed, and
the role of Renewal Aging is illustrated by comparing a Non-Poisson model with a Poisson one, both of them modulated by a
periodic forcing. It is shown that the analysis of Renewal Aging is sensitive to the presence of critical events and that
this property can be exploited to detect Non-Poisson statistics in a time series. As a consequence, it is claimed that, apart
from the characterization of superstatistical features such as the distribution of the intensive parameter or the separation
of the time scales, the Renewal Aging property can give some effort to better determine the role of Non-Poisson critical events
in intermittent systems.
相似文献
972.
曹瑞涛 《杭州师范学院学报(社会科学版)》2006,28(1):106-109
在罗尔斯所设想的独立的政治世界上,持有不同价值观念的人们在交流时所使用的理性乃是"公共理性",这是一种在应用范围、主题和方式上有着严格限制的特殊理性.罗尔斯这种理论曾受到桑德尔的猛烈反驳,对此,罗尔斯在其后期著作中进行了直接或间接的回应,并在这些回应中进一步丰满了公共理性的思想,使之更有可能在一个多元的社会中成为大家乐于接受的交流工具. 相似文献
973.
Valve-based comprehensive two-dimensional gas chromatography (GC × GC) is one of the most compact, robust, and inexpensive GC × GC instrument designs. The major drawback of a valve-based modulation configuration lies in diminished detection sensitivity. This loss in sensitivity is because under typical operating conditions the fraction of the first column (i.e., column 1) effluent transferred to the second column (i.e., column 2) is likely to be ∼5-10%. To address this loss in sensitivity, we report the development of a unique total-transfer (i.e., 100%) valve-based GC × GC, without adding complexity to the instrumentation. The new instrument design relies upon simply blocking one of the appropriate ports of the high-speed six-port diaphragm valve that is used as the modulator between columns 1 and 2. The modulation period and difference in head pressure between columns 1 and 2 are found to be the two primary variables that are controlled to provide good detection sensitivity and 100% mass transfer from column 1 to column 2. The detection sensitivity is better with a longer the modulation period. A limit of detection of 0.03 ng/μl was obtained for octane. This sensitive GC × GC configuration is also shown to provide acceptable separation peak capacity, with good separations achieved for real complex samples: gasoline and Eucalyptus oil, where compounds were spread out over much of the two-dimensional separation space. In principle, this total-transfer, valve-based GC × GC is more portable and less expensive than currently available GC × GC instrumentation. 相似文献
974.
We introduce the concept of a times C-second resolvent families and present the rela- tionship between a times C-resolvent families and a times C-second resolvent families. Moreover, the perturbation and square root for a times C-resolvent families are considered in this paper which generalize the counterparts of C-Cosine operator functions. 相似文献
975.
Peng Sun Lucas P. Veelenturf Said Dabia Tom Van Woensel 《European Journal of Operational Research》2018,264(3):1058-1073
We introduce the time-dependent capacitated profitable tour problem with time windows and precedence constraints. This problem concerns determining a tour and its departure time at the depot that maximizes the collected profit minus the total travel cost (measured by total travel time). To deal with road congestion, travel times are considered to be time-dependent. We develop a tailored labeling algorithm to find the optimal tour. Furthermore, we introduce dominance criteria to discard unpromising labels. Our computational results demonstrate that the algorithm is capable of solving instances with up to 150 locations (75 pickup and delivery requests) to optimality. Additionally, we present a restricted dynamic programing heuristic to improve the computation time. This heuristic does not guarantee optimality, but is able to find the optimal solution for 32 instances out of the 34 instances. 相似文献
976.
This paper addresses the integration of two emerging classes of scheduling problems which, for the most part, have evolved independently. These problem classes are (i) scheduling problems with time-dependent processing times and (ii) scheduling problems with rate-modifying activities (RMAs). The integration of these two concepts is motivated by human operators who experience fatigue while carrying out tasks and take rest breaks for recovery, but is also applicable to machines that experience performance degradation over time and require maintenance in order to sustain acceptable production rates. We explore a sequence-independent, single processor makespan problem with position-dependent processing times and prove that under certain conditions, the optimal policy is to schedule the RMA in the middle of the task sequence. 相似文献
977.
978.
齐次树上三次循环树指标马氏链的强极限定理 总被引:1,自引:0,他引:1
首先给出齐次树上三次循环树指标马氏链的定义,利用构造鞅的方法,研究齐次树上三次循环树指标马氏链的强极限定理,并给出其状态及状态序偶发生频率的强大数定律. 相似文献
979.
《Optimization》2012,61(2):283-289
An inventory system with unit demand, varying ordering levels and random lead times is considered in this paper. Ordering level is determined by the number of demands during last lead time. The ordering quantity will be such as to bring back the inventory level to S at the ordering epoch. No backlog is permitted. The time dependent probability distribution of the inventory level is obtained. Correlation between the number of demands during a lead time and the length of the next inventory dry period is obtained and it is illustrated by an example. 相似文献
980.
** Email: dohi{at}rel.hiroshima-u.ac.jp The paper deals with an economic manufacturing quantity (EMQ)problem for an unreliable manufacturing system in both continuous-and discrete-time settings. The time to machine failure andcorrective and preventive repair times of the production facilityare assumed to follow arbitrary probability distributions. Thetraditional method of determining the EMQ policy for a failure-pronemanufacturing system is based on the minimization of the long-runaverage cost in the steady state. In this paper, an alternativecriterion of optimality called cost effectiveness is introduced.The criteria for the existence and uniqueness of the optimalproduction time maximizing the cost effectiveness are derivedanalytically under general failure and specific repair (correctiveand preventive) time distributions. The optimal cost-effectiveand average cost production policies are numerically calculatedand compared in terms of their performances. 相似文献