Academic articles

Developing, Simulating and Managing Distributed COM Applications with XJ DOME


XJ DOME is a set of tools and technologies for those who wish to speed up development of distributed COM applications and improve their quality and manageability. DOME supports several development phases (graphical modeling, code generation, simulation and deployment), as well as run-time (monitoring and management). DOME is tuned to work with MS Visual C++.

COVERS 3.0- A C++ Based Graphical Modeling and Simulation Tool


We consider a modeling language and a simulation environment based on objectoriented principles and aimed to help in the design of reactive systems. The language framework includes diagrams of object structure and interconnection, statecharts as a behavior description, and C++ for data objects and functions. Timed Transition Systems are used as a semantical model. COVERS enables the user to perform the whole modeling-simulation-analysis cycle within a single MS Windows-based graphical environment. We overview the code generation, model execution and visualization of results. The correspondence between COVERS language and the Unified notation is outlined.

Analysis of a Distributed Election Algorithm Using COVERS 3.0 - A Case Study


We present a case study which demonstrates a methodology of using modeling language and simulation environment for reactive system design and analysis. We describe how a distributed algorithm can be modeled and investigated on the base of a compact set of carefully selected concepts and methods offered by COVERS - an MS Windows-based object-oriented modeling and simulation tool. COVERS modeling language framework includes diagrams of object structure and interconnection, statecharts as a behavior description, and C++ for data objects and functions. Timed Transition Systems are used as a semantic model. COVERS enables the user to perform the whole modeling-simulation-analysis cycle within a single graphical environment. In the paper we overview our experience in using the tool for analysis of a distributed election algorithm which has been described elsewhere.

Systems Modeling, Simulation and Analysis Using COVERS Active Objects


We consider a modeling language and a simulation environment based on object-oriented principles and aimed to help in the design of reactive systems. The language framework includes diagrams of object structure and interconnection, statecharts as a behavior description, and C-I+ for data objects and functions. Timed Transition Systems are used as a semantical model. COVERS enables the user to perform the whole modeling-simulation-analysis cycle within a single MS Windows-based graphical environment. We overview the code generation, model execution and visualization of results. The correspondence between COVERS language and the Unified notation is outlined.

COVERS 3.0 - An Object-Oriented Environment for Modeling, Simulation and Analysis of Real-Time Concurrent Systems


We give an overview of COVERS 3.0 - an MS Windowsbased modeling and simulation environment for concurrent real-time systems. COVERS offers an objectoriented modeling methodology based on C-F+ and Statecharts behavioral notation. Timed Transition Systems are used as a model semantics. COVERS enables the user to perform the whole modeling and simulation cycle within a single graphical environment, where every bit of the specification is animated and accessible. Extendible libraries of frequently used objects are supplied, as well as models of classical systems for educational purposes. COVERS 3.0 is free software available over the Internet for non-commercial use.

COVERS - A Tool for the Design of Real-Time Concurrent Systems


We give an overview of the existing commercial tools for the design of real-time concurrent systems and propose a list of features the ideal design environment should have. Then the COVERS tool is described. Its underlying abstract model is a derivative of the Timed Transition System. The concrete modelling language is based upon the structural, behavioral and data processing views on the real-time concurrent system. COVERS supports a sequential subset of Statecharts and ANSI C. The formal semantics of the concrete model is presented. We describe a method of testing the real time temporal properties using spy processes, and, briefly, debugging and performance analysis means.

Spare Part Management in a Testing Workshop


Spare part management is essential to many organizations, since excess inventory leads to high holding costs and stock outs can greatly impact operations performance, but it is a major problem in the testing work shop in Robert Bosch China Diesel (RBCD) Wuxi. The workshop is used to test the functionality of the injectors, such as those statistics for pressure, electro conductivity, etc. After implementing the automated tower storage in the work shop, the workshop supervisor applied monthly order policy to purchase spare parts, which means at the end of each month, he/she will check the consumption of last month’s spare parts and make orders according to that data. However, in order to control the inventory of spare parts and achieve minimum total inventory cost of those parts, the (Q, r) model was suggested to make the monthly order, realizing the goal of maximizing the net profit of injectors.

Towards a Virtual Factory Prototype


A virtual factory should represent most of the features and operations of the corresponding real factory. Some of the key features of the virtual factory include the ability to assess performance at multiple resolutions and generate analytics data similar to that possible in a real factory. One should be able to look at the overall factory performance and be able to drill down to a machine and analyze its performance. It will require a large amount of effort and expertise to build such a virtual factory. This paper describes an effort to build a multiple resolution model of a manufacturing cell. The model provides the ability to study the performance at the cell level or at the machine level. The benefits and limitations of the presented approach and future research directions are also described.

Using a Discrete-event Simulation Model for Efficient Operation of Tunnel Boring Machines


A tunnel boring machine (TBM) is the primary resource in a tunnel construction project and generally its advance rate is equal to the performance rate of the whole project. Regarding previous studies, the utilization factor of TBMs is approximately 50% most of the time. The process of repair and maintenance of various parts of the machine and the logistic equipment takes 50% of the time. This case study aims to simulate the whole process of TBM tunneling in Ahwas subway project and find out how different scenarios of repair and maintenance can affect the utilization factor of the TBM. The model is developed using discrete-event simulation (DES) method.

Strategic Planning of Logistics for Offshore Arctic Drilling Platforms Supported by Simulation


The operation of offshore drilling platforms requires a lot of logistics: supply of platforms by platform supply vessels (PSVs), backward transportation of waste in containers and transportation of oil by tankers to export ports. The severe weather conditions of the Arctic Ocean increase the number of possible disruptions that influence the logistic system. The operation of PSVs and tankers has multiple constraints and interactions. An agent-based simulation has been developed in AnyLogic to support the strategic planning of logistics by year 2042. The presentation discusses the use of the model to determine the required number of vessels and compare different options of crude oil outbound logistic network design.