Academic articles

Operational Strategies for Managing Supply Chain Disruptions: Simulation of External Factor Impact on a Semiconductor Industry


The study explores the critical need to address vulnerabilities within the semiconductor supply chain, given its global network and production timelines. It showcases the application of system dynamics simulation through AnyLogic software. The researchers assess the impacts of external disruptions and observe the change in customer orders, revenue, and distribution center stock in different operational strategies for managing supply chain disruptions.

Semiconductor Manufacturing Process: A Research Paper on the Impact of Lot Priorities on Cycle Times


The semiconductor manufacturing process is complex and requires smart planning to achieve production efficiency. This semiconductor research paper examines how prioritizing certain batches affects the time it takes to process others. Using a simulation model, the researchers tested different scenarios to see what worked best. The results obtained will help improve the management of production lines.

Dynamic Ride Sharing Using Traditional Taxis and Shared Autonomous Taxis: A Case Study of NYC


This study analyzes the potential benefits and drawbacks of taxi sharing using agent-based modeling. New York City (NYC) taxis are examined as a case study to evaluate the advantages and disadvantages of ride sharing using both traditional taxis (with shifts) and shared autonomous taxis. Compared to existing studies analyzing ride sharing using NYC taxi data, reserarchers from the Purdue University proposed a model that incorporates individual heterogeneous preferences; compared traditional taxis to autonomous taxis; and examined the spatial change of service coverage due to ride sharing.

Simulation of maintenance strategies in mechanized tunneling


Mechanized tunneling is one of the most common methods used for underground constructions for infrastructure systems. Since a tunnel boring machine (TBM) represents a non-redundant single machine system, the efficiency of maintenance work highly impacts the overall project performance. The wear and tear of cutting tools is a critical, but mostly unknown process. To plan the maintenance work of cutting tools efficiently, it is necessary to know the current tool conditions and adapt the planned maintenance strategies to the actual status accordingly. In this paper, an existing theoretical empiric surrogate model to describe cutting tool conditions will be used and implemented as a software component within a process simulation tool that manages TBM steering parameters. Further, different maintenance setups for TBM cutting tools are presented and evaluated. To prove the capability of the presented approach, a case study will show the effects that improved maintenance work can have on project performance.

Towards airspace rules for future UAS-based delivery


The growth of the nascent UAS industry will be affected by the airspace coordination rules between drones because these rules can impact business profitability. Few analyses have been reported to support design of commercial UAS operations in low-altitude commercial urban airspace. Analysis of minimum horizontal separation is critical for designing safe and efficient UAS delivery systems. In this paper a constructive simulation model is used to analyze and evaluate proposed UAS airspace traffic. A high density of delivery drones could create a bottleneck in a drone-based supply chain very quickly, especially when a high minimum horizontal separation standard is required. This paper proposes a simple idea on how to organize low-altitude UAS traffic, and evaluates the idea using a simulation model. Additional implications and future work needed in relation to UAS-based delivery are also discussed.

Analysis of future UAS-based delivery


Commercial use of Unmanned Aerial System (UAS) has the potential to reshape the delivery market and to open new business opportunities to small businesses, e.g., local stores, pharmacies, restaurants, as well as to large international and national businesses and government entities, e.g., Amazon, Google, UPS, power companies, and USPS. Simulation models can examine the value added to current business operations, the effects of radical shifts in current operations, and the formation of new types of businesses. This paper presents an envisioned future UAS delivery business operation models and develops a theoretical constructive simulation model. The conducted simulation analysis based on full factorial design estimated causalities between multiple independent and dependent business and policy factors e.g. drone velocity, flying altitude, number of drones, delivery demand, route type, maximum drone fly-time, number of orders completed, time average drone density, order time, drone utilization, and reachability of customers.

From desktop to large-scale Model Exploration with Swift/T


As high-performance computing resources have become increasingly available, new modes of computational processing and experimentation have become possible. This tutorial presents the Extreme-scale Model Exploration with Swift/T (EMEWS) framework for combining existing capabilities for model exploration approaches (e.g., model calibration, metaheuristics, data assimilation) and simulations (or any “black box” application code) with the Swift/T parallel scripting language to run scientific workflows on a variety of computing resources, from desktop to academic clusters to Top 500 level supercomputers. We will present a number of use-cases, starting with a simple agent-based model parameter sweep, and ending with a complex adaptive parameter space exploration workflow coordinating ensembles of distributed simulations. The use-cases are published on a public repository for interested parties to download and run on their own.

An Object-oriented Process Flow Approach to ARGESIM Comparisons "Flexible Assembly System" with AnyLogic


Simulator: AnyLogic is an object-orientated, general-purpose simulator for discrete, continuous and hybrid applications. It supports modelling with UML – RT and the underlying modelling technology is based on Java. Since Version 4.5 AnyLogic provides different advanced libraries as the Enterprise Library which implements often used discrete model object classes like sources, conveyors, and sinks.  Model: As the Comparison addresses the possibility to define and combine submodels, the objectoriented approach of AnyLogic, using the Enterprise Library, seems natural. The model consists of eight stations connected by some conveyors (all predefined in the Enterprise Library). 

An Object-oriented Hybrid Approach to ARGESIM Comparison "Crane and Embedded Control" with AnyLogic


Simulator: AnyLogic is a general-purpose simulation environment for discrete, continuous and hybrid systems. It employs UML-RT structure diagrams for building hierarchical models in object-oriented way and hybrid statecharts for behaviour specification. The generated model is Java and can be extended with user’s Java code. The simulation engine handles discrete events and dynamically changing sets of algebraic-differential equations. It automatically detects “change” (or “state”) events. Debugging and visualization facilities are present.