Csaba Attila Boer

A survey on distributed simulation in industry

Distributed simulation is used very little in industry, especially when compared with the interest in distributed simulation from research and from the military domain. In order to answer the question why industry lags behind, the authors have carried out an extensive survey, namely a questionnaire targeted at vendors of commercial-off-the-shelf (COTS) simulation packages and a series of open-ended interviews with experts on distributed simulation. Analysis of the answers obtained establish that it is indeed the case that industry is relatively underdeveloped in the area of distributed simulation and also sheds light on the reasons behind this. A categorization of these responses is given using which it is possible to formulate clear guidelines for further developments of standards for distributed simulation.

Distributed simulation in industry -- a survey, part 3 -- the HLA standard in industry

Distributed simulation, more specifically the HLA standard, is hardly applied in industry. We have conducted an extensive survey with COTS (commercial off-the-shelf) simulation package vendors and simulation experts, both from defence and industry, that focuses, amongst others, on the question what the reasons are behind this phenomenon. In this paper we analyze the reactions that we obtained, categorizing them into arguments related to distributed simulation in general, arguments related to HLA and arguments pertaining to the embedding of HLA concepts in COTS packages. These answers will lead us, we believe, to insights that can serve as guidelines to make distributed simulation more attractive for the industrial simulation community.

Advanced 3D visualization for simulation using game technology

3D visualization is becoming increasingly popular for discrete event simulation. However, the 3D visualization of many of the commercial off the shelf simulation packages is not up to date with the quickly developing area of computer graphics. In this paper we present an advanced 3D visualization tool, which uses game technology. The tool is especially fit for discrete event simulation, it is easily configurable, and it can be kept up to date with modern computer graphics techniques. The tool has been used in several container terminal simulation projects. From a survey under simulation experts and our experience with the visualization tool, we concluded that realism is important for some of the purposes of visualization, and the use of game technology can help to achieve this goal.

Storage and retrieval of discrete-event simulation models

Abstract Present simulation languages provide the modeler with powerful tools that facilitate the building of discrete-event simulation models. These models can largely be built by using high-level modules containing a lot of built-in functionality. Although such languages greatly reduce the amount of work to build an implementation model, the modeler often has the feeling that he is reinventing the wheel again and again. Perhaps the model he is about to design and implement already exists, or perhaps some model exists that sufficiently resembles the model about to be designed. All this would make it worthwhile to store existing models in a database for later use. In this respect, two aspects are of major interest. Firstly, how can implementation models be stored in a database and how can a modeler retrieve a specific model from such a database? A second theme is closely related to this. If the specified model is not present in the database – and this is expected to be true in most cases – would it then be possible to select a model that, in some sense, is similar to the model that the modeler had specified? In this paper, the feasibility and usefulness of the proposed approach is investigated with a focus on Arena models.

Controls: emulation to improve the performance of container terminals

Nowadays container terminals are struggling with a continuously increasing volume. Therefore, they are searching for solutions to increase throughput capacity without expanding their physical footprint. Furthermore, they aim to increase their productivity on vessels in order to be able to handle bigger ships with larger call sizes in the same time frame. A terminal operating system (TOS) plays a major role in today¿s terminal operations as it supports planning, scheduling and equipment control. Recently more and more tasks are performed by the TOS - stowage planning, grounding decisions, equipment dispatching - and therefore, they need to be well-tuned to the operation, which remains a terminal specific characteristic. In this paper, an approach is presented to test and tweak the TOS and train operators on a virtual terminal. The implementation of this approach has been successfully applied during several TOS update or replacement projects for Rotterdam, Hong Kong, Norfolk, Virginia and Antwerp.

The possible role of a backbone architecture in real-time control and emulation

The complexity of technical systems that need to be designed and researched is gradually increasing. In order to be competitive and to satisfy the demands of the market, thorough analyses and early risk assessment of the systems are required. System investigation might involve some changes that might entail the redesigning or even redeveloping of some parts of the system. Modifications are usually expensive, time consuming and risky. Consequently, there is a need for methods that examine the possible effects of the modifications before investing in the alteration of the system. There are four methods that are used to study the behavior of a system: simulation, emulation, real-time control and prototyping. In this paper we discuss an approach for a distributed architecture that supports these four testing methods and the interaction between them.

Improving container terminal efficiency through emulation

Container terminals are struggling with a continuously increasing volume and increasing performance demands. As space is typically limited, terminals are searching for solutions to increase throughput capacity without expanding their physical footprint. Furthermore, they aim to increase their productivity on vessels in order to be able to handle bigger ships with larger call sizes in the same time frame. A terminal operating system (TOS) plays a major role in todays terminal operations, as it supports planning, scheduling and equipment control. Recently more and more tasks are performed by the TOS. These tasks need to be well-tuned to the operation (such as stowage planning, grounding decisions and equipment dispatching) in order to reduce cost and risk. In this paper, we present a meanwhile proven, safe and inexpensive approach to test and tweak the TOS and train operators on an emulated virtual terminal. This novel approach in the field of container terminals has been successfully applied during the previous 3 years at over 15 container terminals.

Plan validation for container terminals

Terminal operating systems (TOS) play a major role in todays terminal performance. A TOS is used to create operational plans in order to ensure timely handling of vessels, trucks and trains at minimal operational cost. Creating appropriate operational plans forms a challenge for the planners, as plans should take into account a variety of aspects, such as grounding decisions and equipment dispatching. In addition, several decisions have to be made within a limited time frame, couple of hours before starting the operation. Wrong decisions in the plan can have major impact on the operation and implies financial and safety consequences. Planners face these problems only when the plans are actually executed in live operation. In this article, we propose to use a fast yet accurate simulation of both the operation and the TOS in order to support planners to investigate and adapt plans before they are applied in live operations.

Ranking a list of discrete-event models

It has been demonstrated that Arena simulation models can be parameterized and stored in a relational database for later use. In this way an Arena model can be uniquely described by assigning the right values to the corresponding parameters. These parameters contain detailed information concerning type and number of modules, entities and routes which entities follow through the system. A modeler could query such a database hoping that it would contain the Arena (sub)model that one has in mind. Unfortunately, an exact match will seldom occur but the database might contain one or more similar models. In earlier work a numerical algorithm was proposed resulting in a ranked list of simulation models in the database. According to this the lower a model is ranked the more it resembles the specified model. This model depends on a number of weight factors. In this paper the ranking algorithm is evaluated by carrying out a number of experiments.