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Introduction to the special issue on Advances in Manufacturing Systems

T. van Woensel, J. Buzacott, S. Gershwin, G. Liberopoulos, J. MacGregor Smith, S. Meerkov, B. Tan
2010 Annals of Operations Research  
The proposed approximate, aggregate Markov chain formulation is decomposed into submodels, each with a product-form steady-state distribution.  ...  A decomposition/aggregation method is proposed by Mhada and Malhamé for the performance analysis of single part unreliable transfer lines under CONWIP disciplines.  ... 
doi:10.1007/s10479-010-0753-7 fatcat:ypmruh3ohfhbpl7pwn3b7q257m

Page 5 of Geographical Analysis Vol. 19, Issue 1 [page]

1987 Geographical Analysis  
However, the development of more complex movement heuristics is needed to extend this approach to more complex environments.  ...  Alternative journey structures are provided by travel heuristics. This approach provides a fairly good replication of shopping journeys.  ... 

A review of models of landscape change

William L. Baker
1989 Landscape Ecology  
Models of landscape change may serve a variety of purposes, from exploring the interaction of natural processes to evaluating proposed management treatments.  ...  Distributional models, while widely used, exclude spatial detail important for most landscape ecological research.  ...  I thank the Department of Geography at the University of Hawaii at Manoa for providing office space and assistance during the writing.  ... 
doi:10.1007/bf00137155 fatcat:eupgdy3yn5hxrcs2cg7iphrvfy

Radio resource allocation in fixed broadband wireless networks

T.K. Fong, P.S. Henry, K.K. Leung, Xiaoxin Qiu, N.K. Shankaranarayanan
1998 IEEE Transactions on Communications  
For reasonable system parameters, the SRA method delivers a throughput in excess of 30% per sector while permitting a given frequency band to be re-used in every sector of every cell.  ...  To support a target data rate of 10 Mb/s, a bandwidth of several MHz is required. Since radio spectrum is expensive, the bandwidth need to be reused very aggressively.  ...  ACKNOWLEDGEMENTS Thanks are due to Lek Ariyavisitakul, Kapil Chawla, Len Cimini, Vinko Erceg, Tony Rustako and Arty Srivastava for their helpful discussions.  ... 
doi:10.1109/26.681421 fatcat:5bkqxupkrbaxpogbde43kq3jky

A software tool for learning about stochastic models

R.A. Sahner, K.S. Trivedi
1993 IEEE Transactions on Education  
With respect to the solution of dependability and performability models, we identify three practical issues: largeness, stiness, and non-exponentiality, and we discuss a variety of approaches to deal with  ...  them, including some of the latest research eorts.  ...  Phase approximations for a class of non-Markovian models have been implemented in GSHARPE [39] .  ... 
doi:10.1109/13.204817 fatcat:6oz6jyudk5dqzfcct772f4jn4u

Performability modelling tools and techniques

Boudewijn R. Haverkort, Ignas G. Niemegeers
1996 Performance evaluation (Print)  
A prerequisite of a more practical but not less important nature is the availability of software tools to support the modelling techniques and to allow system designers to incorporate the new techniques  ...  Moreover, these tools should be structured such that the models can be specified at a level that is easy to understand for a system designer, and that the mathematical aspects are hidden as much as possible  ...  In the former case a variant of the well-known LU-decomposition algorithm is used which reduces fill-in by a heuristic technique for pivot selection and which deals in a special way with very small elements  ... 
doi:10.1016/0166-5316(94)00038-7 fatcat:z3en5yre2rczpg6hyh6du7sn2u

Model-based evaluation: from dependability to security

D.M. Nicol, W.H. Sanders, K.S. Trivedi
2004 IEEE Transactions on Dependable and Secure Computing  
Alone, neither of these approaches is fully satisfactory, and we argue that there is much to be gained through the development of a sound model-based methodology for quantifying the security one can expect  ...  The development of techniques for quantitative, model-based evaluation of computer system dependability has a long and rich history.  ...  ACKNOWLEDGMENT We would like to thank our past and current research sponsors for supporting this work, and our colleagues and students, both past and present, who also contributed to the research described  ... 
doi:10.1109/tdsc.2004.11 fatcat:nli5cwcxrbfchkzhvojdttwpym

Lumping partially symmetrical stochastic models

S. Baarir, M. Beccuti, C. Dutheillet, G. Franceschinis, S. Haddad
2011 Performance evaluation (Print)  
Lumping of (finite) MCs is a useful method for dealing with large chains [17] .  ...  The analysis of stochastic processes in general is a hard problem, in fact often simulation is the only viable option, while in some cases algorithms for the computation of approximations or bounds on  ...  at the level of aggregates, then both approaches are suitable and a heuristic rule for defining the approach minimizing the number of instanced "macrostates" can be used.  ... 
doi:10.1016/j.peva.2010.09.002 fatcat:qxidcu2a4ray5mldklodry5ote

Small increases in agent-based model complexity can result in large increases in required calibration data [article]

Vivek Srikrishnan, Klaus Keller
2019 arXiv   pre-print
However, ABMs are often not calibrated in a statistical sense. Here we examine the impact of data record structure on the calibration of an ABM for housing abandonment in the presence of flood risk.  ...  This emphasizes the need for utilizing independent lines of evidence to select sound and informative priors.  ...  ACKNOWLEDGEMENTS The authors would like to thank Ben S. Lee, Joel Roop-Eckart, Tony E. Wong, and Skip Wishbone for their input and contributions. This work was partially supported by the Na-  ... 
arXiv:1811.08524v3 fatcat:k242pdcsg5defeukclwulhc3xq

An Analytical Model of a New Packet Marking Algorithm for TCP Flows [chapter]

Giovanni Neglia, Vincenzo Falletta, Giuseppe Bianchi
2005 Lecture Notes in Computer Science  
As a consequence, packet marking schemes can be devised to differentiate packets belonging to a same TCP flow, with the goal of improving the experienced performance.  ...  The model combines three specific sub-models aimed at describing i) the TCP sources aggregate ii) the marker, and iii) the network status.  ...  The Network Model Sources Network In [43] we have proposed a network submodel, extending the approach proposed in [35] for a best-effort scenario to a DiffServ one, where routers deploy RIO (we indicate  ... 
doi:10.1007/978-3-540-30573-6_1 fatcat:l4gchpwmgbe6tmp4vqhjuri7wq

An analytical model of a new packet marking algorithm for TCP flows

Giovanni Neglia, Vincenzo Falletta, Giuseppe Bianchi
2006 Computer Networks  
As a consequence, packet marking schemes can be devised to differentiate packets belonging to a same TCP flow, with the goal of improving the experienced performance.  ...  The model combines three specific sub-models aimed at describing i) the TCP sources aggregate ii) the marker, and iii) the network status.  ...  The Network Model Sources Network In [43] we have proposed a network submodel, extending the approach proposed in [35] for a best-effort scenario to a DiffServ one, where routers deploy RIO (we indicate  ... 
doi:10.1016/j.comnet.2005.09.003 fatcat:rpwhpdncrfbfzhyrbn3xxjor3a

A decomposition approach for stochastic reward net models

Gianfranco Ciardo, Kishor S. Trivedi
1993 Performance evaluation (Print)  
We present a decomposition approach for the solution of large stochastic reward nets (SRNs) based on the concept of near-independence.  ...  We apply our technique to the analysis of a flexible manufacturing system. Short Title: A Decomposition Approach for Stochastic Reward Net Models.  ...  The estimates of φ 12 obtained from A 1 and A 2 , φ 12 and φ (2) 12 do not coincide. We could simply average them, as we did for the computation of u 12 , but we can use a better heuristic.  ... 
doi:10.1016/0166-5316(93)90026-q fatcat:do5rblpldbaltmd6rtvuoqevrq

Vacation Model [chapter]

2013 Encyclopedia of Operations Research and Management Science  
A vector n-space is a set of vectors or points, each with n components, and rules for vector addition and multiplication by real numbers. Euclidean 3-space is a vector space.  ...  Many of the papers and books in the literature describe various heuristic approaches for solving vehicle routing problems.  ...  A standard heuristic approach for solving many point-to-point vehicle routing and scheduling problems consists of the following steps: (a) Specify K, the fleet size.  ... 
doi:10.1007/978-1-4419-1153-7_200894 fatcat:zm5qf6pzmzbepkc55xmzunolhq

Event-based estimation of interacting Markov chains with applications to electrocardiogram analysis

PETER C. DOERSCHUK, ROBERT R. TENNEY, ALANS S. WlLLSKY
1990 International Journal of Systems Science  
The problem of electroci~rdiogram analysis serves both as the primary motivation for this investigation and as the source of a case study we describe.  ...  The principal locus ofthe paper is on the development of an approach that overcomes the combinatorial explosion of truly optimal estimation algorithms.  ...  Mark for the opportunity to use the M.I.T. Biomedical Engineering Center's computational facility. The  ... 
doi:10.1080/00207729008910362 fatcat:haytgyv2hrhz5ddmuvvj3wycsa

Toward Conceptualizing Trip-Chaining Behavior: A Review

Jean-Claude Thill, Isabelle Thomas
2010 Geographical Analysis  
Alternative journey structures are provided by travel heuristics. This approach provides a fairly good replication of shopping journeys.  ...  However, the development of more complex movement heuristics is needed to extend this approach to more complex environments.  ... 
doi:10.1111/j.1538-4632.1987.tb00110.x fatcat:mw4arfeqq5gbzany5l2mhdnds4
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