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Extendable object-based program's (processes) architecture from logically partitioned object model to physically distributed object model is a key feature onto expanding the programming abilities, resource use/share possibilities and space-limited opportunities. The distributed environment, beside the design, requires new approaches and implementation methods. The idea behind this paper is to provide implementation analysis of Java remote method invocation (RMI) and Common object request broker architecture (CORBA) as most known distributed object oriented architectural platforms. Explicitly focused on the issues of such distributed object-oriented implementation methods. [ABSTRACT FROM AUTHOR]

Since the dynamic behavior of wireless networks inherits different communication patterns for the execution processes of the desired parallel tasks and the occurrence processes of handoff operations, the available reliability metrics are not applicable to study and analyze such networks. Therefore, in this paper, we propose a novel Petri net modeling methodology for accurately calculating the reliability of wireless networks that incorporate theses aspects, such as wireless CORBA network. The proposed reliability methodology is developed based on using the End-to-End Expected Instantaneous Reliability (EIR) measure. The EIR has the capability to measure the reliability of wireless networks that incorporate the handoff processes as well as the service processes. In the proposed technique, we firstly build Generalized Stochastic Petri Net (GSPN) performance model for describing the different communication pattern that can occur among the various network resources under the execution of parallel tasks. Secondly, we build GSPN performance model for describing the handoff communication processes among the various network resources. Finally, we build generic reliability model consists of the following parts: the first part describes the execution of the desired parallel tasks, the second part illustrates the mobility characteristic introduced by handoff processes, and the third part describes the dynamic behavior of failure processes of network resources. The developed model has the capability to accurately describe the occurrence of many handoff processes in CORBA network. We study and analyze the various reliability results as well as the performance results obtained from the developed GSPN models under the effect of communication distance among the CORBA network resources. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a new service for CORBA applications that orchestrates the timely execution of the tasks of a distributed real-time system in a flexible way. It follows the CORBA philosophy of complementing the CORBA standard with additional services that solve specific problems and facilitate using CORBA in complex applications. The service has been designed for highly coupled applications that execute over LANs. It provides a synchronous framework to synchronize distributed applications that is open to accepting and removing components on-line, with reduced impact on the application timing. It also provides the flexibility to use different distributed scheduling policies that can override the local operating systems schedulers. This paper describes the service architecture and implementation as well as its best-case performance on low computing power hardware with the QNX OS and connected to a switched Ethernet network. Finally the usage and of the service is illustrated with one case study: the synchronization of several robots in a welding process. [Copyright &y& Elsevier]

Abstract: An interceptor is a generic architecture pattern, and has been used to resolve specific issues in a number of application domains. Many standard platforms such as CORBA also provide interception interfaces so that an interceptor developed for a specific application can become portable across systems running on the same platform. SOAP frameworks are commonly used platforms to build Web Services. However, there is no standard way to build interceptors portable across current SOAP frameworks, although, some of them provide proprietary interceptor solution within individual framework, such as Axis, XFire, and etc. In this paper, we propose the portable interceptor mechanism (PIM) consisting of a set of application programming interfaces (API) on SOAP engine, a core component of a SOAP framework. An interceptor is able to receive messages passing through the SOAP framework from the SOAP engine via these APIs. Furthermore, the proposed PIM facilitates run-time lifecycle management of interceptors that is a crucial feature to many application domains but is not fully supported by CORBA standard. For concept proving, we implement the proposed PIM on two popular SOAP frameworks, namely, Axis and XFire. We also discuss a number of implementation issues including the performance and reliability of PIM. [Copyright &y& Elsevier]

In order to overcome the shortcomings of traditional EJB, CORBA, and publish/subscribe middleware software architecture, an efficient software component framework suitable for embedded distributed computing environment is proposed. The software architecture is based on the open service gateway initiative ( OSGi) standard, and can be used in multi-communications protocol environment by adding a transmission abstraction layer. It is characterized by versatility, high stability and less memory footprint. The experimental results show that the software is superior to the traditional software architecture in memory footprint, startup time and service interface response time. It can meet the harsh conditions of the embedded environment. [ABSTRACT FROM AUTHOR]

Abstract: The increasing number of ITS (Intelligent Transportation Systems) equipment spread across cities offers tremendous possibilities in the development of distributed smart environments. A middleware layer located between the operating system and the final application can be used for the communication among the equipment to spontaneously act and cooperate among themselves. However, this middleware layer has also a computational cost that should be quantified as it can affect the main application. This paper defines a methodology for such quantification using as case example a modern ITS equipment related to vehicle tracking using artificial vision. Experimental results illustrate the proposed methodology. [Copyright &y& Elsevier]

Software Communications Architecture (SCA) compliant radios typically contain a large number of software components. Some software components provide access to hardware devices while others perform signal processing. By interacting with each other, the software components implement a radio communications standard. To interact, the software components use a middleware called Common Object Request Broker Architecture (CORBA). Using CORBA, each interaction is carried out as an exchange of messages between two components. CORBA supports two main types of messaging: one-way and two-way. This article explores the differences between the two types of messaging and provides performance metrics. The article also describes design approaches that can be used to avoid common pitfalls associated with the use of both types of messaging. [ABSTRACT FROM AUTHOR]

The aim of this work was to analyze the cooperation effciency of the distributed objects based on the CORBA standard. The obtained results show the possibilities of application to the object-relational databases or ob- ject oriented computation of data received via the network from the object managed data base. The distributed objects for the client-server model were implemented in Java and C++ languages. All possible configurations of the implementation for the client and the server were analyzed. Best results were received for the client and the server implementation in C++ language. The worst results were received for the client and the server implementation in Java. [ABSTRACT FROM AUTHOR]

A detailed solution to the remote monitoring and diagnosis system for a rolling mill is introduced. The hardware and software structure of remote monitoring and diagnosis system is presented. The structure of the system is made up of four subsystems, namely online monitoring subsystem, data servo subsystem, database service subsystem and www server subsystem. Software module of system includes seven parts, namely online monitoring module, data query module, fault information query module, trend analysis module, diagnosis analysis module, engineer station module and eigenvalue query module. The system adopts B/S model and integrates CORBA technology with SOAP/Web Service technology. It makes dynamic display and traversing for a great deal of on-line data and Firewall traversal possible. It has run a long time that proves that the system interface is friendly and easy to use. It has better security, good portability, expandability and stability. It can judge the running-condition of a rolling mill in real time. [ABSTRACT FROM AUTHOR]

This paper presents a CORBA wrapper which encapsulates a generic anthropomorphic industrial robot. Since this wrapper abstracts the communications, building applications that require remote manipulation or coordination of several devices may be easily achieved by using it. This article describes an implementation of this wrapper over a real-time operating system (RTOS), namely RTAI. This type of OS ensures determinism in the movement operations of the robot. Also, a low resource consuming implementation of the CORBA specification, namely ORBit, has been used to wrap the robot and implement the communications with other devices. Finally, as a matter of example, we present how this wrapper is used to coordinate the operation of several robots in a typical 'pick & place' operation. [ABSTRACT FROM AUTHOR]

An interactive software environment is proposed that combines numerical simulation codes with optimization software packages in an automated and modular way. It simplifies the experimentation with varying objective functions for common optimization problems such as parameter estimation and optimal experimental design that are frequently encountered in computational science and engineering. The design philosophy takes into consideration the need for derivatives of potentially large-scale simulation codes via automatic differentiation as well as distributed computing in a heterogenous environment via CORBA. [ABSTRACT FROM AUTHOR]

This paper presents the development of new Humanoid Robot Control Architecture (HRCA) platform based on Common Object Request Broker Architecture (CORBA) in a developmental biped humanoid robot for real-time teleoperation tasks. The objective is to make the control platform open for collaborative teleoperation research in humanoid robotics via the internet. Meanwhile, to generate optimal trajectory generation in bipedal walk, we proposed a real time generation of optimal gait by using Genetic Algorithms (GA) to minimize the energy for humanoid robot gait. In addition, we proposed simplification of kinematical solutions to generate controlled trajectories of humanoid robot legs in teleoperation tasks. The proposed control systems and strategies was evaluated in teleoperation experiments between Australia and Japan using humanoid robot Bonten-Maru. Additionally, we have developed a user- friendly Virtual Reality (VR) user interface that is composed of ultrasonic 3D mouse system and a Head Mounted Display (HMD) for working coexistence of human and humanoid robot in teleoperation tasks. The teleoperation experiments show good performance of the proposed system and control, and also verified the good performance for working coexistence of human and humanoid robot. [ABSTRACT FROM AUTHOR]

Abstract: Grid computing has become an effective computing technique in recent years. This paper develops a virtual workflow system to construct distributed collaborative applications for Grid users. The virtual workflow system consists three levels: abstract workflow system, translator and concrete workflow system. The research highlight of the implementation is that this workflow system is developed based on CORBA and Unicore Grid middleware. Furthermore, this implementation can support legacy application developed with Parco and C++ codes. This virtual workflow system can provide efficient GUI for users to organize distributed scientific collaborative applications and execute them on Grid resources. We present the design, implementation, and evaluation of this virtual workflow system in the paper. [Copyright &y& Elsevier]

The questions of corporate systems development based on integration of CORBA and Java technologies and tools are rated. Here is brought the comparative analysis of using the program models and integration of distributed corporate systems development technologies. [ABSTRACT FROM AUTHOR]

Abstract: Management, allocation and scheduling of heterogeneous resources for complex distributed real-time applications is a challenging problem. Timing constraints of applications may be fulfilled by the proper use of real-time scheduling policies, admission control and enforcement of timing constraints. However, it is not easy to design basic infrastructure services that allow for easy access to the allocation of multiple heterogeneous resources in a distributed environment. In this paper, we present a middleware for providing distributed soft real-time applications with a uniform API for reserving heterogeneous resources with real-time scheduling capabilities in a distributed environment. The architecture relies on standard POSIX OS facilities, such as time management and standard TCP/IP networking services, and it is designed around CORBA, in order to facilitate modularity, flexibility and portability of the applications using it. However, real-time scheduling is supported by proper extensions at the kernel-level, plugged within the framework by means of dedicated resource managers. Our current implementation on Linux supports the reservation of the CPU, disk and network bandwidth. However, additional resource managers supporting alternative real-time schedulers for these resources, as well as additional types of resources, may be easily added. We present experimental results gathered on both synthetic applications and a real multimedia video streaming case study, showing the advantages deriving from the use of the proposed middleware. Finally, overhead figures are reported, showing the sustainability of the approach for a wide class of complex, distributed, soft real-time applications. [Copyright &y& Elsevier]

The spread of communication networks, and in particular the growth of affordable broadband Internet in developed countries, has enabled organizations to share their computational resources. The paper presents the study of effectiveness between the techniques like Java RMI and CORBA which are currently used to build distributed resources. The obtained results showed that the RMI technology is much faster than the CORBA one in case seeking algorithms. [ABSTRACT FROM AUTHOR]

This paper presents a new approach regarding interoperability. The novelty of the proposed solution resides in using a proxy object for each parameter object in order to avoid serialization. The main guidelines and the architecture related to developing a framework in order to automatically generate the source code for communication between platforms are proposed. Finally, there are summarized the contributions of this work and future improvements. [ABSTRACT FROM AUTHOR]

We propose a platform for distributed multimedia systems. The proposed platform is implemented using the Netscape Portable Runtime (NSPR) and the Cross-Platform Component Object Model (XPCOM). This ensures system portability, flexibility and performance. The platform is equipped with bandwidth management components that control the transfer rates between components, allowing real-time streaming across multiple networks. [ABSTRACT FROM AUTHOR]

Abstract: The use of formal description techniques (FDTs), and specifically SDL, has emerged as an interesting way of designing embedded real time distributed systems (ERTDSs) taking into account the increasing complexity of this kind of system. The communication platform for these ERTDSs should be included at the design stage in order to consider the behaviour of the communications. RT-CORBA is an interesting alternative as a middleware for real-time distributed applications because, unlike standard CORBA, it guarantees predictable temporal response to invocations to remote objects. We propose a set of design patterns in SDL for the RT-CORBA middleware so that users can integrate the communication behavior into their designs. This approach provides three important results: firstly, it is possible to carry out the simulation and validation of the whole system including communications; secondly, the implementation stage is simplified because the integration of RT-CORBA allows code to be generated from the design. Finally, different analysis techniques at design level for ERTDS including the temporal behavior of RT-CORBA middleware can be carried out. To apply our proposals we have integrated the design of RT-CORBA with the SDL specification of a distributed control application called Siroco. [Copyright &y& Elsevier]

Integrated Integration Definition Language (IDEF0) is an activity-based modelling technique for modelling the activities and information flows in a manufacturing system. Based on the entities involved in the system and the interactions abstracted from IDEF0 approach, an object-oriented method based on Common Object Request Broker Architecture (CORBA) is developed in a hierarchically distributed control system. The application of CORBA as a middleware for the development of distributed object systems simplifies the implementation of clients and servers at different locations. The data and general methods in distributed controllers are integrated into servers; the controller is able to communicate with the server through the communication mechanism of CORBA. A prototype system which is constructed to validate the flexible manufacturing system is presented in details. [ABSTRACT FROM AUTHOR]

Integrated Integration Definition Language (IDEF0) is an activity-based modelling technique for modelling the activities and information flows in a manufacturing system. Based on the entities involved in the system and the interactions abstracted from IDEF0 approach, an object-oriented method based on Common Object Request Broker Architecture (CORBA) is developed in a hierarchically distributed control system. The application of CORBA as a middleware for the development of distributed object systems simplifies the implementation of clients and servers at different locations. The data and general methods in distributed controllers are integrated into servers; the controller is able to communicate with the server through the communication mechanism of CORBA. A prototype system which is constructed to validate the flexible manufacturing system is presented in details. [ABSTRACT FROM AUTHOR]