This study proposes an exact algorithm for the precedence-constrained singlemachine scheduling problem to minimize total job completion cost where machine idle time is forbidden. The proposed algorithm is an extension of the authors’ previous algorithms for the problem without precedence-constraints and is based on the SSDP (Successive Sublimation Dynamic Programming) method. Numerical experime...

In this paper we propose an indexing structure for bitemporal databases. Such structure is based on two trees, one indexing valid time and another indexing transaction time. The trees share pointers to the actual data records, which are thus not duplicated. Bitemporal queries are processed by dividing the query in two parts, a valid time part and a transaction time part. Each tree is searched a...

This paper gives the positive answer to the question posed in the title for a wide class of minimization criteria including the maximum completion time, maximum lateness , total completion time, total weighted completion time, total tardiness, total weighted tardiness, number of late jobs and the weighted number of late jobs. That is any scheduling problem for m identical parallel machines to m...

Applying lean production concepts to precast fabrication have been proven promising. However, foreman encounters difficulties in arranging weekly work plans. The objective of this research is to overcome the difficulty when arranging weekly work plans in concrete element prefabrication. Current practices in arranging weekly work plans are fairly basic, and depending heavily on experience, there...

Branch and bound algorithms for Mixed-Integer Linear Programming (MILP) almost universally branch on a single variable to create disjunctions. General linear expressions involving multiple variables are another option for branching disjunctions, but are not used for two main reasons: (i) descendent LPs tend to solve more slowly because of the added constraints, so the overall solution time is i...

The trust-region subproblem minimizes a general quadratic function over an ellipsoid and can be solved in polynomial time using a semidefinite-programming (SDP) relaxation. Intersecting the feasible set with a second ellipsoid results in the two-trust-region subproblem (TTRS). Even though TTRS can also be solved in polynomial-time, existing algorithms do not use SDP. In this paper, we investiga...

Investing in research and development spending (R&D) affects total factor productivity (TFP).Recently new theories of economic growth have emphasized the relationship between R&D and TFPand also identified a number of channels through which a country’s R&D affects TFP of its tradepartner. This study seeks to estimate the effect of agricultural R&D and education spending and someother factors on...

It is shown that the energy dependence of the time lags in Cygnus X-1 excludes any significant contribution of the standard reflected component to the observed lags. The conclusion is valid in the 0.1–10 Hz frequency range where time lags have been detected with high enough significance. In fact the data hint that reflected component is working in opposite direction, reducing the lags at energi...

in this paper, the bernstein polynomials are used to approximate the solutions of linear integral equations with multiple time lags (iemtl) through expansion methods (collocation method, partition method, galerkin method). the method is discussed in detail and illustrated by solving some numerical examples. comparison between the exact and approximated results obtained from these methods is...