Mariusz Nowostawski

Parallel genetic algorithm taxonomy

Genetic algorithms (GAs) are powerful search techniques that are used to solve difficult problems in many disciplines. Unfortunately, they can be very demanding in terms of computation load and memory. Parallel genetic algorithms (PGAs) are parallel implementations of GAs which can provide considerable gains in terms of performance and scalability. PGAs can easily be implemented on networks of heterogeneous computers or on parallel mainframes. We review the state of the art on PGAs and propose a new taxonomy also including a new form of PGA (the dynamic deme model) which was recently developed.

Ontologies for Interaction Protocols

In this paper we propose reducing the degree of human interpretation currently necessary to understand an interaction protocol by describing at an abstract level the required agent actions that must be ‘plugged into’ the protocol for it to be executed. In particular, this can be done by designing and publishing ontologies describing the input and output data that are processed during the protocol’s execution together with the actions and decisions that the agents must perform. An agent (or agent developer) that has previously defined mappings between the internal agent code and the actions and decisions in an ontology would then be able to interpret any interaction protocol that is defined with reference to that ontology. The discussion is based on the use of Coloured Petri Nets to represent interaction protocols and the Unified Modeling Language (UML) for ontology modelling. An alternative approach using Agent UML (AUML) is also outlined.

A MULTI-AGENT SYSTEM FOR THE INTEGRATION OF DISTRIBUTED ENVIRONMENTAL INFORMATION

Abstract This paper describes a multi-agent platform to be used for the integration of environmental information that may be distributed over a network. The system is designed to work as a collection of collaborating agents. Information sources are encapsulated as data source agents (DSAs) that accept messages in an agent communication language. Here we describe how queries can be entered into the system and information collected from multiple sources. A key component of the query module is the planner agent, which takes a query and transforms it first to a calculus, then to an algebraic expression in order to break it into subqueries which an executor agent can send to the DSAs. As part of this process, the query is translated from user-level ontologies to lower level ontologies relevant to the DSAs. Query results need not be returned within an ACL message, but may instead be represented by a Common Object Request Broker Architecture (CORBA) object reference which may be used to obtain the result set. The architecture and operation of these agent components is described and an example is presented of how environmental information can be queried.

Parkinson's disease and essential tremor classification on mobile device

Similarities in physiological and psychological symptoms of Parkinsons disease and Essential Tremor make accurate diagnosis of these conditions difficult. We have developed a smartphone-based application that uses discrete wavelet transforms and support vector machines to discriminate between Parkinsons and Essential postural tremors with over 96% of accuracy. We have demonstrated that attention and distraction can be used to efficiently discriminate between these two disorders and we propose a novel method that uses the influence of attention and distraction while recording the tremor. Our findings confirm that there are significant differences in postural tremors with different attention and distraction tasks. With respect to those differences we have effectively demonstrated that attention and distraction can be used to efficiently discriminate between the two disorders.

From Institutions to Code: Towards Automated Generation of Smart Contracts

Blockchain technology has emerged as a solution to consistency problems in peer to peer networks. By now, it has matured as a solution to a range of use cases in which it can effectively provide the notion of third party trust without the need for a trusted (physical) third party, which makes it an attractive coordination mechanism for distributed systems. To promote the wide adoption of this technology, we yet lack mechanisms that make the specification and interpretation of smart contracts accessible to a broader audience. In this work, we propose a modeling approach that supports the semi-automated translation of human-readable contract representations into computational equivalents in order to enable the codification of laws into verifiable and enforceable computational structures that reside within a public blockchain. We identify smart contract components that correspond to real world institutions, and propose a mapping that we operationalize using a domain-specific language in order to support the contract modeling process. We explore this capability based on selected examples and plot out directions for future research on smart contracts.

Multi-agent interaction technology for peer-to-peer computing in electronic trading environments

Open trading environments involve a type of peer-to-peer computing characterised by well-defined interaction protocols that are used by the traders and sometimes updated dynamically. New traders can arrive at any time and acquire the protocols that are current. Multi-agent system technology is appropriate for these circumstances, and in this paper we present an approach that can be used to support multiple trader agents on multiple computing platforms. The approach involves the use of FIPA-compliant trader agents which (a) incorporate micro-agents for specific local tasks and (b) use coloured Petri nets in order to keep track of the local context of agent conversations. In order to enhance efficiency and employ standard transport services, the trader agents interact with peers on other platforms by means of JXTA technology. We illustrate the working of our approach by examining the operation of an example multi-agent system in commodities trading scenario.

Multi-Agent System Interaction Protocols in a Dynamically Changing Environment

An area where multi-agent systems can be put to effective use is for the case of an open collection of autonomous problem solvers in a dynamically changing environment. One example of such a situation is that of environmental management and emergency response, which can require the joint cooperation of a distributed set of components, each one of which may be specialised for a specific task or problem domain. The various stakeholders in the process can all be represented and interfaced by software agents which collaborate with each other toward achieving a particular goal. For such situations new agents that arrive on the scene must be apprised of the group interaction protocols so that they can cooperate effectively with the existing agents. In this paper we show how this can be done by using coloured Petri net representations for each role in an interaction protocol and passing these nets dynamically to new agents that wish to participate in a group interaction. We argue that multi-agent systems are particularly suited for such dynamically changing environments, but their effectiveness depends on their ability to use adaptive interaction protocols.

Developing a smartphone ‘app’ for public health research: the example of measuring observed smoking in vehicles

Background We have developed manual methods to gather data on the point prevalence of observed smoking in road vehicles. To enable the widespread international collection of such data, we aimed to develop a smartphone application (app) for this work. Methods We developed specifications for an app that described the: (1) variables that could be collected; (2) transfer of data to an online repository; (3) user interface (including visual schematics) and (4) processes to ensure the data authenticity from distant observers. The app functionality was trialled in roadside situations and the app was made publicly available. Results The smartphone app and its accompanying website were developed, tested and released over a period of 6 months. Users (n=18) who have registered themselves (and who met authentication criteria), have reported no significant problems with this application to date (observing 20 535 vehicles as of 5 July 2012). The framework, methodology and source code for this project are now freely available online and can be easily adapted for other research purposes. The prevalence of smoking in vehicles was observed in: Poland 2.7% (95% CI 2.3% to 3.1%); Australia 1.0% (95% CI 0.7% to 1.3%); New Zealand 2.9% (95% CI 2.6% to 3.2%)—similar to results using preapp methods in 2011 (3.2%, 95% CI 3.1% to 3.3%). Conclusions This project indicates that it can be practical and feasible for health researchers to work together with information science researchers and software developers to create smartphone apps for field research in public health. Such apps may be used to collect observational data more widely, effectively and easily than through traditional (non-electronic) methods.

A multi-level approach and infrastructure for agent-oriented software development

This paper describes an agent-oriented architecture for software development that supports the use of agent-oriented concepts at multiple levels of abstraction. The architecture supports the systematic use of agent-based notions throughout the software development process. The paper describes (a) the implementation of micro-agents in Java, (b) how they have been used to fashion the architectural framework for the construction of more complex agents based on the Foundation for Intelligent Physical Agents (FIPA) specifications, and (c) the Conversation Manager that facilitates the capability of agents to conduct complex conversations with other agents.

Modelling and visualizing agent conversations

Although the notion of conversations has been discussed for some time as a way in which to provide an abstract representation of extended agent message exchange, there is still no consensus established concerning how to use these abstractions effectively. This paper describes a layered approach based on coloured Petri Nets that can be used for modelling complex, concurrent conversations among agents in a multi-agent system. The approach can be used both to define simple conversation protocols and to define more complex conversation protocols composed of a number of simpler conversations. With this method it is possible (a) to capture the concurrent characteristics of a conversation, (b) to capture the state of a conversation at runtime, and (c) to reuse conversation structures for the processing of multiple concurrent messages.