We study an iterative beam search algorithm for the permutation flowshop (makespan and flowtime minimization). This combines branching strategies inspired by recent branch-and-bounds a guidance strategy LR heuristic. It obtains competitive results on large instances compared to state-of-the-art algorithms, reports many new-best-so-far solutions VFR benchmark minimization) Taillard (flowtime wit...

diamondoids are cage-like saturated hydrocarbons consisting of fused cyclohexane rings. thediamondoids family of compounds is one of the best candidates for molecular building blocks (mbbs)in nanotechnology to construct organic nanostructures compared to other mbbs known so far. thechallenge is to find a route for self-assembly of these cage hydrocarbons and their applications in thebottom-up s...

objectives: nowadays, snap-fits are used in the automotive industry as a proper alternative for mechanical joints, cabling joints, and car interior lining joints. due to the special form of these joints, which are assembled manually, the contact area between snap-fits and the worker's fingertips can be too small. this can cause skin pain on the worker's fingertips. therefore, an ergonomic study...

with the growth in customers’ demand diversification, mixed-model u-lines (mmul) have acquired increasing importance in the area of assembly systems. there are generally two different approaches in the literature for balancing such systems. some researchers believe that since the types of models can be very diverse, a balancing approach without simultaneously sequencing of models will not yield...

Amyloid-β (Aβ) self-assembly into cross-β amyloidfibrils is implicated in a causative role in Alzheimer’s disease pathology.Uncertainties persist regarding the mechanisms of amyloid self assembly and the role of metastable prefibrillar aggregates. Aβ fibrilsfeature a sheet-turn-sheet motif in the constituent β-strands; as such, turn nucleation has been proposed as a rate-limiting step in the se...

Proper planning of assembly lines is one of the production managers’ concerns at the tactical level so that it would be possible to use the machine capacity, reduce operating costs and deliver customer orders on time. The lack of an efficient method in balancing assembly line can create threatening problems for manufacturing organizations. The use of assembly line balancing methods cannot balan...

The four-machine flowshop scheduling problem is investigated with the objective of minimizing total completion time. Job processing times are uncertain where only lower and upper bounds known. This common in some manufacturing environments. Some mathematical (dominance) relations established, an algorithm (with ten scenarios) proposed. proposed converts to a single machine for which optimal sol...

The issue of sequencing and scheduling has received considerable critical attention in many fields since the early 1950s. In this research, we studied an important production scheduling system, which generally called flexible (or hybrid) flowshop scheduling problem (FFSP or HFSP). We studied this production system with an important restriction called the no-wait. The objective was to optimize t...

The three-machine flowshop scheduling problem to minimize total completion time is studied where setup times are treated as separate from processing times. Setup and processing times of all jobs on all machines are unknown variables before the actual occurrence of these times. The lower and upper bounds for setup and processing times of each job on each machine is the only information that is a...