We derive formulas for mean deep coalescence cost, for either a fixed species tree or a fixed gene tree, under probability distributions that satisfy the exchangeability property. We then apply the formulas to study mean deep coalescence cost under two commonly used exchangeable models—the uniform and Yule models. We find that mean deep coalescence cost, for either a fixed species tree or a fix...

Time and space assembly line balancing considers realistic multi-objective versions of the classical assembly line balancing industrial problems. It involves the joint optimisation of conflicting criteria such as the cycle time, the number of stations, and/or the area of these stations. The different problems included in this area also inherit the precedence constraints and the cycle time limit...

Time and space assembly line balancing considers realistic multiobjective versions of the classical assembly line balancing industrial problems involving the joint optimization of conflicting criteria such as the cycle time, the number of stations, and/or the area of these stations. In addition to their multi-criteria nature, the different problems included in this field inherit the precedence ...

in many real world assembly line systems which the work-piece is of large size more than one worker work on the same work-piece in each station. this type of assembly line is called multi-manned assembly line (mal). in the classical multi-manned assembly line balancing problem (malbp) the objective is to minimize the manpower needed to manufacture one product unit. apart from the manpower, othe...

In production systems of automobile manufacturers multi-variant products are assembled on paced mixed-model assembly lines, which have to be supplied by a lean in-house logistic with containers of different sizes, alternative supply policies and different number of parts. The assignment of operations to workplaces within the assembly line balancing problem and the assignment of containers to su...

This research presents a Simulated Annealing based technique to address the assembly line balancing problem for multiple objective problems when paralleling of workstations is permitted. The Simulated Annealing methodology is used for 23 line balancing strategies across seven problems. The resulting performance of each solution was studied through a simulation experiment. Many of the problems c...

optimal balancing is a new approach based on optimal control a which modes, controls and the amount of equilibrium scale are calculated simultaneously. this approach has a significant effect on increasing performance of industrial robots which causes maximum decreasing of energy consumption. despite many applications of robotics such as welding and gluing, the path is predefined , but other unk...

This research was conducted to enhance the productivity of targeted sewing line at ABC textile company. The existing SAMs, capacity for various operations, and several required machines were collected. Moreover, obtained figures observed analyzed by using time study motion study, certain improvements made line. Results indicated that SAMs operations A B minimized -13.64% -14.54% respectively; w...

Assembly line balancing is a classic ill-structured problem where total enumeration is infeasible and optimal solutions uncertain for industrial problems. A quantitative approach to classifying problem difficulty and solution quality is therefore important. Two existing measures of difficulty, Order Strength and West Ratio are compared to a new compound expression of difficulty, Project Index. ...

Products such as cars, trucks, and heavy machinery are assembled by two-sided assembly line. Assembly line balancing has significant impacts on the performance and productivity of flow line manufacturing systems and is an active research area for several decades. This paper addresses the line balancing problem of a two-sided assembly line in which the tasks are to be assigned at L side or R sid...