Yu-Cheng Chou

An embeddable mobile agent platform supporting runtime code mobility, interaction and coordination of mobile agents and host systems

Abstract Agent technology is emerging as an important concept for the development of distributed complex systems. A number of mobile agent systems have been developed in the last decade. However, most of them were developed to support only Java mobile agents. In order to provide distributed applications with code mobility, this article presents a library, the Mobile-C library, that allows a mobile agent platform, Mobile-C, to be embeddable in an application to support mobile C/C++ codes carried by mobile agents. Mobile-C uses a C/C++ interpreter as its Agent Execution Engine (AEE). Through the Mobile-C library, Mobile-C can be embedded into an application to support mobile C/C++ codes carried by mobile agents. Using mobile C/C++ codes, it is easy to interface a variety of low-level hardware devices and legacy systems. Through the Mobile-C library, Mobile-C can run on heterogeneous platforms with various operating systems. The Mobile-C library has a small footprint to meet the stringent memory capacity for applications in mechatronic and embedded systems. The Mobile-C library contains different categories of Application Programming Interfaces (APIs) in both binary and agent spaces to facilitate the design of mobile agent based applications. In addition, a rich set of existing APIs for the C/C++ interpreter employed as the AEE allows an application to have complete information and control over the mobile C/C++ codes residing in Mobile-C. With the synchronization mechanism provided by the Mobile-C library for both binary and agent spaces, simultaneous processes across both spaces can be coordinated to get correct runtime order and avoid unexpected race condition. The study of performance comparisons indicates that Mobile-C is about two times faster than JADE in agent migration. The application of the Mobile-C library is illustrated by dynamic runtime control of a mobile robot’s behavior using mobile agents.

Ch MPI: Interpretive Parallel Computing in C

The message passing interface lets users develop portable message passing programs for parallel computing in C, C++, and Fortran. When combined with an MPI C/C++ library, Ch, an embeddable C/C++ interpreter for executing C/C++ programs interpretively, lets developers rapidly prototype MPI C/C++ programs without having to compile and link.

Open Source Ch Control System Toolkit and Web-Based Control System Design for Teaching Automatic Control of Linear Time-Invariant Systems

The Ch Control System Toolkit (CCST) is a software package for the design and analysis of control systems. It is a C/C++ class with member functions for solving control problems in a user‐friendly C/C++ interpreter, Ch. Based on the CCST, a Web‐based Control System Design and Analysis System (WCSDAS), and a Web‐based Controller/Compensator Design Module (WCCDM), have been developed. In this article, using the CCST, WCSDAS, and WCCDM for teaching automatic control of linear time‐invariant systems is presented. With the CCST, students are able to solve control problems with only a few lines of C/C++ code. The CCST can also be used to develop various interactive utility programs that will assist students in learning control systems without any programming requirements. With the Web‐based WCSDAS and WCCDM tools, students can interactively design and analyze control systems via a Web browser. The CCST, WCSDAS, and WCCDM are open source software packages. These software tools have been used for teaching undergraduate control courses at the University of California, Davis and Michigan Technological University.

Mobile Agent-Based Integration Framework for Flexible Dynamic Job Shop Scheduling

Although production scheduling has been extensively studied, it is limited in the scope of applications. A mobile agent based flexible dynamic scheduling framework is presented in this article as a scheme to integrate various scheduling models, approaches, and algorithms, and flexibly and autonomously adapt the disturbances in the shop floor. Therefore, such a mobile agent based framework can help expand the scope of applications in the production scheduling field. In this framework, there are three kinds of main agents, including order data agent, scheduling model agent, and cell data agent. The order and cell data agents are designed to acquire dynamically calculated and formatted data from the systems and devices. The scheduling model agent is designed to obtain the optimal solution for distributed manufacturing cells to achieve high performance, such as minimizing the energy consumption. Devices, such as machine tools, are integrated into the framework through intelligent embedded terminals, which can be used by human operators or triggered by sensors to acquire the real-time processing data and on-the-spot conditions. A C based multi-agent platform, which is called Mobile-C, is adopted to develop the mobile agents for real-time and resource constrained applications with interface to hardware in different execution environments. A computational experiment of energy-saving scheduling based on generic algorithm is presented to validate the proposed mobile agent-based dynamic scheduling framework.Copyright

An autonomic mobile agent-based system for distributed job shop scheduling

This paper presents an autonomic mobile agent-based system for distributed job shop scheduling. The system matches the autonomic system reference architecture proposed by the IBM and has the IBM-defined fundamental self-managing properties so that it can manage itself with little human intervention. The system conforms to the IEEE FIPA (Foundation for Intelligent Physical Agents) standard. The interoperability between the systems agents and other agents from many active heterogeneous FIPA compliant agent platforms can be ensured. The system supports the execution of C/C++ mobile agent codes. Thus, it is applicable to a variety of applications, especially for distributed mechatronic and embedded systems. An overall architecture of the system and some implementation details about the agency and agents in the system are presented in this article. An energy saving job shop scheduling example is used to validate the self-configuration property of the system.

Teaching Automatic Control of Engineering Systems Using Open Source CH Control System Toolkit and Web-Based Design and Analysis System

Ch Control System Toolkit (CCST) is a software package for design and analysis of control systems. It is implemented as a class with member functions to run in the user-friendly C/C++ interpreter Ch. Based on the CCST, a Web-based Control System Design and Analysis System (WCDAS) has been developed. In this article, using CCST and WCDAS to teach automatic control of engineering systems is presented. Using CCST, students are able to write programs easily with a few lines of C/C++ code to solve practical engineering problems. By solving control system design and analysis problems in C/C++ , the programming skills gained in the course are applicable to other areas of engineering. CCST and WCDAS are open source. Students are able to examine the source code to understand the implementation of theories and algorithms in software. Based on CCST and WCDAS, the Web-based Controller/Compensator Design Module (WCCDM) has also been developed for teaching and student learning. Using these Web-based tools, students can perform design and analysis of control systems interactively through a Web browser remotely. The CCST, WCDAS, and WCCDM have been used to teach an undergraduate course on Automatic Control of Engineering Systems at the University of California, Davis. All software packages and teaching materials for this course are available on the internet. They can be downloaded and modified to teach similar courses with different requirements.Copyright

Mobile Agent Based Autonomic Dynamic Parallel Computing

Parallel computing is widely adotped in scientific and engineering applications to enhance the efficiency. Moreover, there are increasing research interests focusing on utilizing distributed networked computers for parallel computing. The Message Passing Interface (MPI) standard was designed to support portability and platform independence of a developed parallel program. However, the procedure to start an MPI-based parallel computation among distributed computers lacks autonomicity and flexibility. This article presents an autonomic dynamic parallel computing framework that provides autonomicity and flexibility that are important and necessary to some parallel computing applications involving resource constrained and heterogeneous platforms. In this framework, an MPI parallel computing environment consisting of multiple computing entities is dynamically established through inter-agent communications using the IEEE Foundation for Intelligent Physical Agents (FIPA) compliant Agent Communication Language (ACL) messages. For each computing entity in the MPI parallel computing environment, a load-balanced MPI program C source code along with the MPI environment configuration statements are dynamically composed as a mobile agent code. A mobile agent wrapping the mobile agent code is created and sent to the computing entity where the mobile agent code is retrieved and interpretively executed. An example of autonomic parallel matrix multiplication is given to demonstrate the self-configuration and self-optimization properties of the presented framework.Copyright

Development of a Bio-Production Execution System for Agricultural Operations Management

An open-source bio-production execution system (BES) is proposed to bridge the information gap between the upstream system (center office) and the downstream systems (in-field machines/sensors) to facilitate upstream decision making. The architecture and the functions of the BES are illustrated. The functions of the BES are able to handle the information related to agricultural operations management (AOM). The implementation concerns for the BES regarding different aspects such as bio-production machines (BMs) and bio-production sensors (BSs) are discussed. The implementation of the Web-based user interface for the BES using an interpretive C-based CGI toolkit is described. The potential use of the BES in AOM is demonstrated through two application examples in pistachio harvesting and spraying operations.

Interpretive MPI for Parallel Computing

Message Passing Interface (MPI) is a standardized library specification designed for message-passing parallel programming on large-scale distributed systems. A number of MPI libraries have been implemented to allow users to develop portable programs using the scientific programming languages, Fortran, C and C++. Ch is an embeddable C/C++ interpreter that provides an interpretive environment for C/C++ based scripts and programs. Combining Ch with any MPI C/C++ library provides the functionality for rapid development of MPI C/C++ programs without compilation. In this article, the method of interfacing Ch scripts with MPI C implementations is introduced by using the MPICH2 C library as an example. The MPICH2-based Ch MPI package provides users with the ability to interpretively run MPI C program based on the MPICH2 C library. Running MPI programs through the MPICH2-based Ch MPI package across heterogeneous platforms consisting of Linux and Windows machines is illustrated. Comparisons for the bandwidth, latency, and parallel computation speedup between C MPI, Ch MPI, and MPI for Python in an Ethernet-based environment comprising identical Linux machines are presented. A Web-based example is given to demonstrate the use of Ch and MPICH2 in C based CGI scripting to facilitate the development of Web-based applications for parallel computing.Copyright

Mobile Agent-Based Computational Steering for Distributed Simulation

Two challenging problems in the area of scientific computation are long computation time and large-scale, distributed, and diverse data sets. As the scale of science and engineering applications rapidly expands, these two problems become more manifest than ever. This paper presents the concept of Mobile Agent-based Computational Steering (MACS) for distributed simulation. The MACS allows users to apply new or modified algorithms to a running application by altering certain sections of the program code without the need of stopping the execution and recompiling the program code. The concept has been validated through an application for dynamic CFD data post processing. The validation results show that the MACS has a great potential to enhance productivity and data manageability of large-scale distributed computational systems.Copyright