Designing interaction systems for distributed applications

In this article, we discuss the explicit design of interaction mechanisms for developing distributed applications. When interactions between system parts require an explicit design, the concept of an interaction system comes into play. We define criteria that designers can use to decide whether an interaction system requires an explicit design. We also show that designers can apply both middleware-centered and protocol-centered development approaches in designing an application-level interaction system

Intelligence metasynthesis and knowledge processing in intelligent systems

Intelligence and Knowledge play more and more important roles in building complex intelligent systems, for instance, intrusion detection systems, and operational analysis systems. Knowledge processing in complex intelligent systems faces new challenges from the increased number of applications and environment, such as the requirements of representing domain and human knowledge in intelligent systems, and discovering actionable knowledge on a large scale in distributed web applications. In this paper, we discuss the main challenges of, and promising approaches to, intelligence metasynthesis and knowledge processing in open complex intelligent systems. We believe (1) ubiquitous intelligence, including data intelligence, domain intelligence, human intelligence, network intelligence and social intelligence, is necessary for OCIS, which needs to be meta-synthesized; and (2) knowledge processing should pay more attention to developing innovative and workable methodologies, techniques, tools and systems for representing, modelling, transforming, discovering and servicing the uncertain, large-scale, deep, distributed, domain-oriented, human-involved, and actionable knowledge highly expected in constructing open complex intelligent systems. To this end, the meta-synthesis of ubiquitous intelligence is an appropriate way in designing complex intelligent systems. To support intelligence meta-synthesis, m-interaction can play as the working mechanism to form rn-spaces as problem-solving systems. In building such m-spaces, advancement in knowledge processing is necessary. © J.UCS

Operating Systems Support for End-to-End Gbps Networking

This paper argues that workstation host interfaces and operating systems are a crucial element in achieving end-to-end Gbps bandwidths for applications in distributed environments. We describe several host interface architectures, discuss the interaction between the interface and host operating system, and report on an ATM host interface built at the University of Pennsylvania. Concurrently designing a host interface and software support allows careful balancing of hardware and software functions. Key ideas include use of buffer management techniques to reduce copying and scheduling data transfers using clocked interrupts. Clocked interrupts also aid with bandwidth allocation. Our interface can deliver a sustained 130 Mbps bandwidth to applications, roughly OC-3c link speed. Ninety-three percent of the host hardware subsystem throughput is delivered to the application with a small measured impact on other applications processing

Agent-Based Distributed Resource Allocation in Continuous Dynamic Systems

Intelligent agents and multiagent systems reveal new strategies to design highly flexible automation systems. There are first promising industrial applications of multiagent systems for the control of manufacturing, logistics, traffic or multi-robot systems. One reason for the success of most of these applications is their nature as some form of a distributed resource allocation problem which can be addressed very well by multiagent systems. Resource allocation problems solved by agents can be further categorized into static or dynamic problems. In static problems, the allocations do not depend on time and many resource allocation problem of practical interest can be solved using these static considerations, even in discrete-event systems like manufacturing or logistic systems. However, problems especially in highly dynamic environments cannot be addressed by this pure static approach since the allocations, i.e. the decision variables, depend on time and previous states of the considered system. These problems are hardly considered in the relevant agent literature and if, most often only discrete-event systems are considered. This work focuses on agent-based distributed dynamic resource allocation problems especially in continuous production systems or other continuous systems. Based on the current states of the distributed dynamic system, continuous-time allocation trajectories must be computed in real-time. Designing multiagent systems for distributed resource allocation mainly comprises the design of the local capabilities of the single agents and the interaction mechanisms that makes them find the best or at least a feasible allocation without any central control. In this work, the agents are designed as two-level entities: while the low-level functions are responsible for the real-time allocation of the resources in the form of closed-loop feedback control, the high-level functionalities realize the deliberative capabilities such as long-term planning and negotiation of the resource allocations. Herein, the resource allocation problem is considered as a distributed optimization problem under certain constraints. The agents play the role of local optimizers which then have to coordinate their local solutions to an overall consistent solution. It is shown in this contribution that the described approach can be interpreted as a market-based allocation scheme based on balancing of supply and demand of the resources using a virtual price. However, the agents calculate and negotiate complete supply and demand trajectories using model-based predictions which also leads to the calculation of a price trajectory. This novel approach does not only consider the dynamic behaviour of the distributed system but also combines control tasks and resource allocation in a very consistent way. The approach is demonstrated using two practical applications: a heating system and an industrial sugar extraction process

A survey of agent-oriented methodologies

This article introduces the current agent-oriented methodologies. It discusses what approaches have been followed (mainly extending existing object oriented and knowledge engineering methodologies), the suitability of these approaches for agent modelling, and some conclusions drawn from the survey

Safe and scalable parallel programming with session types

Parallel programming is a technique that can coordinate and utilise multiple hardware resources simultaneously, to improve the overall computation performance. However, reasoning about the communication interactions between the resources is difficult. Moreover, scaling an application often leads to increased number and complexity of interactions, hence we need a systematic way to ensure the correctness of the communication aspects of parallel programs. In this thesis, we take an interaction-centric view of parallel programming, and investigate applying and adapting the theory of Session Types, a formal typing discipline for structured interaction-based communication, to guarantee the lack of communication mismatches and deadlocks in concurrent systems. We focus on scalable, distributed parallel systems that use message-passing for communication. We explore programming language primitives, tools and frameworks to simplify parallel programming. First, we present the design and implementation of Session C, a program ming toolchain for message-passing parallel programming. Session C can ensure deadlock freedom, communication safety and global progress through static type checking, and supports optimisations by refinements through session subtyping. Then we introduce Pabble, a protocol description language for designing parametric interaction protocols. The language can capture scalable interaction patterns found in parallel applications, and guarantees communication-safety and deadlock-freedom despite the undecidability of the underlying parameterised session type theory. Next, we demonstrate an application of Pabble in a workflow that combines Pabble protocols and computation kernel code describing the sequential computation behaviours, to generate a Message-Passing Interface (MPI) parallel application. The framework guarantees, by construction, that generated code are free from communication errors and deadlocks. Finally, we formalise an extension of binary session types and new language primitives for safe and efficient implementations of multiparty parallel applications in a binary server-client programming environment. Our exploration with session-based parallel programming shows that it is a feasible and practical approach to guaranteeing communication aspects of complex, interaction-based scalable parallel programming.Open Acces

Knowledge Nodes: the Building Blocks of a Distributed Approach to Knowledge Management

Abstract: In this paper we criticise the objectivistic approach that underlies most current systems for Knowledge Management. We show that such an approach is incompatible with the very nature of what is to be managed (i.e., knowledge), and we argue that this may partially explain why most knowledge management systems are deserted by users. We propose a different approach - called distributed knowledge management - in which subjective and social (in a word, contextual) aspects of knowledge are seriously taken into account. Finally, we present a general technological architecture in which these ideas are implemented by introducing the concept of knowledge node