scholarly journals Simulating Army Rail Yard Operations at the Port of Bremerhaven

2019 ◽  
Vol 6 (2) ◽  
pp. 95-100
Author(s):  
Joshua Bieger ◽  
Jadalaine Ferrer ◽  
Dillon Riedlinger ◽  
William Xu ◽  
Jeffrey Demarest
Keyword(s):  
Discrete Event ◽  
The United States ◽  
Network System ◽  
Operational Experience ◽  
Military Operations ◽  
Engineer Research ◽  
Event Simulation ◽  
Event Model ◽  
Discrete Event Model

To maintain the United States military’s capability to deploy rapidly across the globe, logistical planning tools, simulations, and models enhance leaders’ decision making abilities. This research develops a discrete event model designed to simulate military operations within a railyard in order to support the Engineer Research and Development Center’s (ERDC) Planning Logistics Analysis Network System (PLANS). The research team chose the Port of Bremerhaven, Germany as a case study due to its relevance to current military operations, granting us access to timely data and stakeholders with recent operational experience. The discrete event simulation (DES) utilizes stochastic processes and multiple layouts in order to analyze the amount of time it takes to move varying amounts of cargo and vehicles and identify potential bottlenecks in the operation.

scholarly journals Approaches to Modeling the Gas-Turbine Maintenance Process

2011 ◽  
Vol 12 (1) ◽  
Author(s):  
Tai-Tuck Yu ◽  
James P. Scanlan ◽  
Richard M. Crowder ◽  
Gary B. Wills
Keyword(s):  
Decision Making ◽  
Gas Turbine ◽  
Discrete Event ◽  
Agent Based Modeling ◽  
Agent Based ◽  
Event Modeling ◽  
Human Decision ◽  
Event Model ◽  
Discrete Event Model

Discrete-event modeling has long been used for logistics and scheduling problems, while multi-agent modeling closely matches human decision-making process. In this paper, a metric-based comparison between the traditional discrete-event and the emerging agent-based modeling approaches is reported. The case study involved the implementation of two functionally identical models based on a realistic, nontrivial, civil aircraft gas turbine global repair operation. The size, structural complexity, and coupling metrics from the two models were used to gauge the benefits and drawbacks of each modeling paradigm. The agent-based model was significantly better than the discrete-event model in terms of execution times, scalability, understandability, modifiability, and structural flexibility. In contrast, and importantly in an engineering context, the discrete-event model guaranteed predictable and repeatable results and was comparatively easy to test because of its single-threaded operation. However, neither modeling approach on its own possesses all these characteristics nor can each handle the wide range of resolutions and scales frequently encountered in problems exemplified by the case study scenario. It is recognized that agent-based modeling can emulate high-level human decision-making and communication closely while discrete-event modeling provides a good fit for low-level sequential processes such as those found in manufacturing and logistics.

Improving Casthouse Throughput Using Discrete-Event Modelling

2011 ◽  
Vol 693 ◽  
pp. 3-9 ◽  
Author(s):  
Bruce Gunn ◽  
Yakov Frayman
Keyword(s):  
Sensitivity Analysis ◽  
Discrete Event ◽  
Casting Machine ◽  
Production Data ◽  
Model Output ◽  
Arrival Times ◽  
Event Simulation ◽  
Modelling System ◽  
Key Parameter

The scheduling of metal to different casters in a casthouse is a complicated problem, attempting to find the balance between pot-line, crucible carrier, furnace and casting machine capacity. In this paper, a description will be given of a casthouse modelling system designed to test different scenarios for casthouse design and operation. Using discrete-event simulation, the casthouse model incorporates variable arrival times of metal carriers, crucible movements, caster operation and furnace conditions. Each part of the system is individually modelled and synchronised using a series of signals or semaphores. In addition, an easy to operate user interface allows for the modification of key parameters, and analysis of model output. Results from the model will be presented for a case study, which highlights the effect different parameters have on overall casthouse performance. The case study uses past production data from a casthouse to validate the model outputs, with the aim to perform a sensitivity analysis on the overall system. Along with metal preparation times and caster strip-down/setup, the temperature evolution within the furnaces is one key parameter in determining casthouse performance.

scholarly journals Discrete-Event Simulation of the Establishment of a Bare Beachhead for Long-Term Joint Logistics over the Shore (JLOTS) Operations

2017 ◽  
Vol 5 (2) ◽  
pp. 123-128
Author(s):  
Marqus Burrell ◽  
Jeffrey Demarest ◽  
Sarah LaRue ◽  
Angelo Martinez ◽  
Wilson Meyer
Keyword(s):  
Discrete Event Simulation ◽  
Discrete Event ◽  
The United States ◽  
Operational Conditions ◽  
Freedom Of Movement ◽  
Event Simulation ◽  
Early Entry ◽  
Sea Transportation ◽  
Development Center

The United States military uses Joint Logistics Over-the-Shore (JLOTS) operations to move soldiers, vehicles, and equipment across the globe for military and humanitarian missions. These logistics operations can only be accomplished through cooperation between commanders in all services.  The U.S. Army Engineer Research and Development Center is developing a tool to analyze a set of early entry alternatives to optimize mission effectives and efficiencies in order to facilitate assured mobility and freedom of movement. This program is currently being developed under the name Planning Logistics Analysis Network System (PLANS). PLANS comprehensively covers air, land, and sea transportation infrastructure, regions of avoidance, and more. This research addresses a gap in strategic and operational planning by modeling the establishment of JLOTS operations on bare beach environments. The West Point developed discrete event simulation will determine the amount of time it takes to prepare a beach to sustain JLOTS operations under varying environmental and operational conditions.

scholarly journals A discrete event model of clinical trial enrollment at eli lilly and company

2007 ◽  
Author(s):  
Bernard M. McGarvey ◽  
Nancy J. Dynes ◽  
Burch C. Lin ◽  
Wesley H. Anderson ◽  
James P. Kremidas ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Discrete Event ◽  
Event Model ◽  
Clinical Trial Enrollment ◽  
Discrete Event Model

Arena-Based Modeling of the Maintenance Operation for a Wind Farm

2013 ◽  
Vol 401-403 ◽  
pp. 2205-2208 ◽  
Author(s):  
Huai Zhong Li ◽  
Tong Jing ◽  
Hong Zhang
Keyword(s):  
Wind Turbines ◽  
Wind Farm ◽  
Discrete Event ◽  
Onshore Wind ◽  
Electric System ◽  
System A ◽  
Factors Influencing ◽  
Event Model ◽  
Main Factors ◽  
Discrete Event Model

Wind energy has become a leading developing direction in electric power. The high cost associated with turbine maintenance is a key challenging issue in wind farm operation as wind turbines are hard-to access for inspection and repair. Analysis of an onshore wind farm is carried out in this paper in terms of the operation, failure, and maintenance. Failures are categorized into three classes according to the downtime. It is found that the pitch, gearbox and generator have the most amount of downtime, while the most number of failures is from the pitch and electric system. A discrete-event model is developed by using Arena to simulate the operation, failure occurrence, and maintenance of the wind turbines, with an aim to determine the main factors influencing maintenance costs and the availability of the turbines in the wind farm.

Sign in / Sign up

Export Citation Format

Share Document