Yao Yiping

Event-Driven Debug Framework for EDEVS Based Components

Debugging EDEVS based components using existing debug frameworks is very time-consuming for the following reasons: Firstly, EDEVS based components are self-contained and are independent of simulation applications, so test case must be designed and implemented beforehand. Secondly, Usually EDEVS based components are hierarchically composed of many subcomponents, so examine the data flow among all these subcomponents is a big job. Thirdly, EDEVS components are designed to run inside a component container built upon Event-scheduling based simulation engine, so debug processes usually lost to the inner logic of the engine. To solve these problems an event-driven EDEVS component debug framework is proposed and its implementation under YHSUPE is presented.

A Model Description Transformation Tool: From Platform-Specific to Platform-Independent

Reuse of simulation models can greatly cut on the software development time and improve development efficiency. However, platform-specific models (PSM) are difficult to be reused on different platforms because their implementation depends on the support of a particular platform. To improve the reusability of the platform-specific models on various platforms, a natural idea is to transform these models into platform-independent models (PIM) by describing simulation models in platform-independent language. Among these platform-independent languages, XML is widely used by many applications like simulation reference markup language (SRML) and open source simulation modeling language (SML) for its good characteristics. Focusing on the transformation demands, we design and implement a model transformation tool which can transform the models developed in platform-specific language (C/CPP) into XML-based model description file (SRML). Our tool can also deal with the model recursive call problems and check the completeness and correctness of models. The case study illustrates that our transformation tool can transform models into XML format correctly and it shows beautiful robustness.

Research and Implementation of Simulation Interactive Technology Based on Parameter File with Variable Number of Parameters

In order to obtain multiple different simulation results, parameters need to be modified constantly during the simulation experiments. The simulation interactive technology based on interactive database (IDB) file is very difficult to operate for users, inducing its low-level simulation running efficiency. This paper introduced a simulation interactive technology based on parameter file with variable number of parameters. It is implemented by associating parameter file with interactive database file, and applied the technology in YHSIM software. The tests and applications demonstrated that the technology can reduce the difficulty for users and the time for operation, and make the Human-Computer Interactive Interface (HCII) more friendly, and further improve the simulation efficiency.

A Bug Reproducing Method for the Debugging of Component-Based Parallel Discrete Event Simulation

Component debugging is critically important for diagnosing failures of programs. In component-based Parallel Discrete Event Simulation (PDES), the bug probably not to be reproduced for the different orders of event processing in different simulation runs, so there is a great challenge in the debugging for components. To solve the problem, this paper proposes a bug reproducing method based on checkpoint/restart mechanism, which schedules a simultaneous interaction event after each event processing to request the checkpoint operation. Moreover, a module called CheckpointRestartMgr (CRM) has been designed to provide checkpoint/restart service for simulation objects. The cost brought from cooperation between Logical Processes when performing checkpoint operation can be reduced through the simultaneous interaction event and CRM. The usage of our method in the debug framework for component-based PDES demonstrates it can be feasible.