Sharif Digital Repository

Supply chain management has gained much interest from researchers and practitioners in recent years. Proposing practical models that efficiently address different aspects of the supply chain is a difficult challenge. This research investigates an integrated production-distribution supply chain problem. The developed model incorporates parties with a specified number of processes to obtain raw materials from the suppliers in order to convert them to semi and final products. These products are then distributed through warehouses to end-distributors having uncertain demands. This uncertainty is captured as a dynamic stochastic data process during the planning horizon and is modeled into a... 

In this paper, we want to solve multi-objective robot path planning problem. A new elitist multi-objective approach is proposed to determine Pareto front based on coefficient of variation. Intelligent water drops (IWD) algorithm is generalized by this approach and as a new multi-objective IWD algorithm. We call our new algorithm CV-based MO-IWD. It tried to optimize two objectives: length and safety of the path. In the CV-based MO-IWD, we want to discover solutions as close to optimal Pareto solutions as possible and find solutions as diverse as possible in the obtained Pareto front. In this way, coefficient of variation of Pareto front is determined in each objective. Then, appropriate... 

The economic viability of industrial processes strongly depends on their safe and reliable operation. The method of inherent safe process design enables systematic consideration of safety measures in order to ensure process safe operation at the early stages of process design. The challenge is that the economic measures that are often considered for the design of industrial processes are often incommensurable with the safety measures. In the present research, a novel framework is proposed in which the safety criteria are quantified based on consequence modeling and aggregated with the economic performance using multi-objective optimization programming. The developed methodology was applied... 

Spacecraft rendezvous and docking are two processes in which a chaser pursues and meets a leader spacecraft in order to perform several mission based tasks. Although in some preliminary design analysis, these two operations may be pursued independently there could be circumstances in which the spacecraft trajectory and attitudes are coupled and interdependent. The present study is based on the presumption that the often independent translational and rotational motions of the spacecraft are coupled as a result of thrust misalignment. So the thrusters not only contribute to the rendezvous translational motion, but also affect the docking reorientation maneuver through their disturbing effects.... 

In this study, multi-criteria shape optimization of an asymmetrical doublecurvature arch dam is presented. Simultaneous cost minimization of dam construction and maximum allowable tensile stress are investigated for an economical and safe design approach in the current study. Pareto front method was used to balance both the economy and safety of the design simultaneously, which can be difficult for both analysts and decision-makers. A non-dominated solution based on the important parameters of dam analysis and design is presented. To help decision-makers in their decision, two different methods are proposed. These methods for the case of an arch dam are Lombardi coefficient and equilibrium... 

The stiffeners and piezoelectric actuators are used in many aerospace structures as an auxiliary layer with laminated composites. A question then arises as to whether we can estimate the percentage of these materials in an efficient design. Due to the high computational cost, it is not easy to answer through numerical solutions. The objective of this paper is concurrently to maximize the buckling load and minimize the weight of the cylindrical shell. To reach this aim, a multi-objective optimization problem is developed based on the closed-form solutions of thermal/mechanical buckling and weight of the piezolaminated shell with eccentric/concentric stiffener. The Non-dominated Sorting... 

Abstract: Advancements in microscale technologies have prompted a demand for high precision micro-manipulation. Microgrippers are the primary means of conducting micro-scale operations, and they significantly affect the procedure's performance. This paper presents a novel optimized design for compliant microgrippers, intending to enhance functionality and durability. The mainframe of the proposed microgripper is based on a compact flexure-based compliant structure with four stages of movement amplification. Experiments were designed based on the L25 Taguchi orthogonal arrays. The experiments were conducted using the finite element method in Abaqus 6.14 workbench. Range of motion and maximum... 

The use of energy storage systems (ESS) and distributed generators (DGs) to improve reliability is one of the solutions that has received much attention from researchers today. In this study, we utilize a multi-objective optimization method for optimal planning of distributed generators in electric distribution networks from the perspective of multi-objective optimization. The objective is to improve the reliability of the network while reducing the annual cost and network losses. A modified version of the multi-objective sine–cosine algorithm is used to determine the optimal size, location, and type of DGs and the optimal capacity, location, and operation strategy of the ESS. Three case... 

Network-on-Chips are now the popular communication medium to support inter-IP communications in complex on-chip systems with tens to hundreds IP cores. Higher scalability (compared to the traditional shared bus and point-to-point interconnects), throughput, and reliability are among the most important advantages of NoCs. Moreover, NoCs can well match current CAD methodologies mainly relying on modular and reusable structures with regularity of structural pattern. However, since NoCs are resource-limited, determining how to distribute application load over limited on-chip resources (e.g. switches, buffers, virtual channels, and wires) in order to improve the metrics of interest and satisfy...