Exact computation of optimal inventory policies over an unbounded horizon
Mathematics of Operations Research
Pinwheel scheduling with two distinct numbers
Theoretical Computer Science
Metropolitan area video-on-demand service using pyramid broadcasting
Multimedia Systems
Approximation algorithms for bin packing: a survey
Approximation algorithms for NP-hard problems
The scheduling of maintenance service
Discrete Applied Mathematics
Scheduling Algorithms for Multiprogramming in a Hard-Real-Time Environment
Journal of the ACM (JACM)
Polynomial-time approximation scheme for data broadcast
STOC '00 Proceedings of the thirty-second annual ACM symposium on Theory of computing
Computers and Intractability: A Guide to the Theory of NP-Completeness
Computers and Intractability: A Guide to the Theory of NP-Completeness
An Efficient Periodic Broadcast Technique for Digital VideoLibraries
Multimedia Tools and Applications
Pfair Scheduling of Generalized Pinwheel Task Systems
IEEE Transactions on Computers
Scheduling techniques for media-on-demand
SODA '03 Proceedings of the fourteenth annual ACM-SIAM symposium on Discrete algorithms
Minimizing Service and Operation Costs of Periodic Scheduling
Mathematics of Operations Research
Nearly optimal perfectly periodic schedules
Distributed Computing - Special issue: Selected papers from PODC '01
Efficient schemes for broadcasting popular videos
Multimedia Systems
Jitter concerns in periodic task systems
RTSS '97 Proceedings of the 18th IEEE Real-Time Systems Symposium
Windows Scheduling Problems for Broadcast Systems
SIAM Journal on Computing
Pushing dependent data in clients-providers-servers systems
Wireless Networks
Dispatching in perfectly-periodic schedules
Journal of Algorithms
Optimally scheduling video-on-demand to minimize delay when server and receiver bandwidth may differ
SODA '04 Proceedings of the fifteenth annual ACM-SIAM symposium on Discrete algorithms
Practical Low Delay Broadcast of Compressed Variable Bit Rate Movies
DCC '06 Proceedings of the Data Compression Conference
Jitter-approximation tradeoff for periodic scheduling
Wireless Networks
Windows scheduling as a restricted version of bin packing
ACM Transactions on Algorithms (TALG)
Operations Research Letters
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The generalized windows scheduling problem for n jobs on multiple machines is defined as follows: Given is a sequence, I=驴(w 1,驴 1),(w 2,驴 2),驴,(w n ,驴 n )驴 of n pairs of positive integers that are associated with the jobs 1,2,驴,n, respectively. The processing length of job i is 驴 i slots where a slot is the processing time of one unit of length. The goal is to repeatedly and non-preemptively schedule all the jobs on the fewest possible machines such that the gap (window) between two consecutive beginnings of executions of job i is at most w i slots. This problem arises in push broadcast systems in which data are transmitted on multiple channels. The problem is NP-hard even for unit-length jobs and a (1+驴)-approximation algorithm is known for this case by approximating the natural lower bound $W(I)=\sum_{i=1}^{n}(1/w_{i})$ . The techniques used for approximating unit-length jobs cannot be extended for arbitrary-length jobs mainly because the optimal number of machines might be arbitrarily larger than the generalized lower bound $W(I)=\sum_{i=1}^{n}(\ell_{i}/w_{i})$ . The main result of this paper is an 8-approximation algorithm for the WS problem with arbitrary lengths using new methods, different from those used for the unit-length case. The paper also presents another algorithm that uses 2(1+驴)W(I)+logw max machines and a greedy algorithm that is based on a new tree representation of schedules. The greedy algorithm is optimal for some special cases, and computational experiments show that it performs very well in practice.