Juha Tiihonen

Towards a general ontology of configuration

This article presents a generalized ontology of product configuration as a step towards a general ontology of configuration, which is needed to reuse and share configuration knowledge. The ontology presented consists of a set of concepts for representing the knowledge on a configuration and the restrictions on possible configurations. The ontology is based on a synthesis of the main approaches to configuration. Earlier approaches are extended with new concepts arising from our practical experience on configurable products. The concepts include components, attributes, resources, ports, contexts, functions, constraints, and relations between these. The main contributions of this work are in the detailed conceptualization of knowledge on product structures and in extending the resource concept with contexts for limiting the availability and use of resources. In addition, constraint sets representing different views on the product are introduced. The ontology is compared with the previous work on configuration. It covers all the principal approaches, that is, connection-based, structure-based, resource-based, and function-based approaches to configuration. The dependencies between the concepts arising from different conceptualizations are briefly analyzed. Several ways in which the ontology could be extended are pointed out.

State-of-the-practice in product configuration — a survey of 10 cases in the Finnish industry

The design and production of goods that satisfy the special needs of individual customers are of central interest to the European industry. A major trend is to improve customer specific adaptation with configurable products. We are interested in the methods, practices and tools that support product configuration tasks. The research described in this paper is meant to guide our future work. We have 1) established a framework for understanding the problem area of product configuration in a fairly wide sense by identifying a number of factors and 2) carried out ten actual case studies using the proposed framework.

Towards recommending configurable offerings

Configuration technologies provide a solid basis for the implementation of a mass customisation strategy. A side-effect of this strategy is that the offering of highly variant products and services triggers the phenomenon of mass confusion, i.e., customers are overwhelmed by the size and complexity of the offered assortments. In this context, recommendation technologies can provide help by supporting users in the identification of products and services fitting their wishes and needs. Recommendation technologies have been intensively exploited for the recommendation of simple products such as books or movies but have (with a few exceptions) not been applied to the recommendation of complex products and services such as computers or financial services. In this paper, we provide an overview of existing approaches to the integration of configuration and recommendation technologies, propose extensions and indicate directions of future work.

Personalized user interfaces for product configuration

Configuration technologies are well established as a foundation of mass customization which is a production paradigm that supports the manufacturing of highly-variant products under pricing conditions similar to mass production. A side-effect of the high diversity of products offered by a configurator is that the complexity of the alternatives may outstrip a users capability to explore them and make a buying decision. In order to improve the quality of configuration processes, we combine knowledge-based configuration with collaborative and content-based recommendation algorithms. In this paper we present configuration techniques that recommend personalized default values to users. Results of an empirical study show improvements in terms of, for example, user satisfaction or the quality of the configuration process.

WeCoTin --A practical logic-based sales configurator

Configurable products can realize the ideal of mass-customization by satisfying individual customer requirements efficiently. IT support provided by configurators enables adapting such products for individual customers efficiently and without errors. Few of numerous configurators have been evaluated with respect to modeling efficacy and performance on several product domains, and few evaluation methods exist. Applying the Design Science method, we describe and evaluate a novel configurator called WeCoTin. WeCoTin is based on a high-level object oriented modeling conceptualization and corresponding modeling language with clear formal semantics. WeCoTin consists of a semi-visual Modeling Tool and a web-based Configuration Tool. It applies an inference engine that follows the logic-based answer set programming paradigm. A way to characterize configuration models is proposed and applied to characterize over 20 real-world configuration models, and to evaluate utility of modeling mechanisms. Furthermore, performance is evaluated with real-world products using a developed method, and found adequate.

A Short History of Configuration Technologies

Abstract Nearly 40-years of configuration technologies motivated us to give this brief overview of the main configuration technological streams. We outline the technological developments in the field starting from the first expert systems of the late 1970s down to today’s configuration solutions. The vastness and intricacies of the configuration field makes it impossible to cover concisely all of its relevant aspects. For the purpose of this overview, we decided to focus on the following four different yet overlapping technological developments: (1) rule-based configurators, (2) early model-based configurators, (3) mainstream configuration environments, and (4) mass customization toolkits.

DevOps Adoption Benefits and Challenges in Practice: A Case Study

DevOps is an approach in which traditional software engineering roles are merged and communication is enhanced to improve the production release frequency and maintain software quality. There seem to be benefits in adopting DevOps but practical industry experiences have seldom been reported. We conducted a qualitative multiple-case study and interviewed the representatives of three software development organizations in Finland. The responses indicate that with DevOps, practitioners can increase the frequency of releases and improve test automation practices. DevOps was seen to encourage collaboration between departments which boosts communication and employee welfare. Continuous releases enable a more experimental approach and rapid feedback collection. The challenges include communication structures that hinder cross-department collaboration and having to address the cultural shift. Dissimilar development and production environments were mentioned as some of the technical barriers. DevOps might not also be suitable for all industries. Ambiguity in the definition of DevOps makes adoption difficult since organizations might not know which practices they should implement for DevOps.

Status quo bias in configuration systems

Product configuration systems are an important instrument to implement mass customization, a production paradigm that supports the manufacturing of highly-variant products under pricing conditions similar to mass production. A side-effect of the high diversity of products offered by a configurator is that the complexity of the alternatives may outstrip a users capability to explore them and make a buying decision. A personalization of such systems through the calculation of feature recommendations (defaults) can support customers (users) in the specification of their requirements and thus can lead to a higher customer satisfaction. A major risk of defaults is that they can cause a status quo bias and therefore make users choose options that are, for example, not really needed to fulfill their requirements. In this paper we present the results of an empirical study that aimed to explore whether there exist status quo effects in product configuration scenarios.

Intelligent Techniques for Configuration Knowledge Evolution

Automated testing and debugging of knowledge bases (such as configuration knowledge bases and feature models) is an important contribution to manage knowledge evolution efficiently. However, existing approaches rely on the assumption of consistent test suites which are always kept up-to-date within the scope of different knowledge base maintenance cycles. In this paper we introduce diagnosis techniques that actively guide stakeholders (knowledge engineers and domain experts) in the process of testing and debugging knowledge bases. These techniques take into account faulty test cases and constraints and recommend diagnoses which are the source of a given inconsistency.

Special issue: Configuration

Configuration can be defined as the composition of a complex product from instances of a set of component types, taking into account restrictions on the compatibility of those component types. For supporting product configuration, different artificial intelligence (AI) approaches are well established as central technologies in industrial configuration systems. However, the wide industrial use of configuration technologies and the increasing size and complexity of configuration problems make the field more challenging than ever. Today the mass customization paradigm has been extended from traditional physical products to the fields of software and service configuration. Configuration systems have evolved into interactive Web-based applications that need to support highly sophisticated knowledge representation and reasoning methods. A wide range of AI techniques are applied in this context: just to mention a few, constraint satisfaction, intelligent user interfaces, preference handling, and explanations. As a successful AI application area, configuration has attracted lasting industrial interest and renewed research, as demonstrated by a series of workshops on configuration that have been arranged in conjunction with leading AI conferences such as IJCAI, ECAI, and AAAI. The goal of this Special Issue on configuration is to demonstrate novel and innovative configuration research as well as new industrial applications of configuration technologies. The contributions of this Special Issue on configuration are a continuation of high-quality papers in previous special issues on configuration published in such journals as IEEE Intelligent Systems (1998), AI EDAM (1998 and 2003), and International Journal of Mass Customization (2010). The seven papers (five fulllength papers and two short papers) were selected from 17 submissions, which corresponds to a full-length paper acceptance rate of 29%. Each paper underwent two to four double-blind reviews by experts in the configuration domain. Papers with a positive reviewer feedback after the first review round were reviewed again to assure that all of the reviewer comments of the first round had been taken into account. The reviews of papers that included acoeditoras an author were managed in a screened manner by uninvolved coeditors or members of the Special Issue program committee. The major topics of the current Special Issue include personalization techniques and algorithms in knowledge-based configuration, different issues of configuration knowledge representation, industrial configuration environments and new application domains, and business-oriented aspects of the application of configuration technologies. “Modeling and Solving Technical Product Configuration Problems” by Andreas Falkner, Alois Haselboeck, Gottfried Schenner, and Herwig Schreiner contains an introduction to the “partner units” problem and provides a discussion of possible alternative knowledge representation approaches (e.g., Unified Modeling Language/Object Constraint Language and Alloy). In addition, the paper contains a discussion of possible approaches to solve the “partner units” problem (from basic backtracking to local search approaches such as “simulated annealing”). The paper is concluded with an in-depth analysis of the applied search algorithms. In their short paper on “Product Configuration as Decision Support: The Declarative Paradigm in Practice” Albert Haag and Steffen Riemann discuss knowledge representation issues in the SAP configuration environment. As an application domain for configuration technologies they introduce the customization of SAP systems. Besides the discussion of the advantages and trade-offs of procedural and declarative knowledge representations, the authors provide an in-depth discussion of the application of assumption-based truth maintenance approaches in their configuration environment. “A Declarative Framework for Work Process Configuration,” written by Wolfgang Mayer, Markus Stumptner, Peter Killisperger, and Georg Grossmann, extends established constraint-based configuration approaches with a constraint representation language for representing specific properties of execution paths in work processes. In this context, a framework for semiautomated process customization is introduced. It integrates the extended constraint approach with a metamodel of work processes. Valid process configurations are then semiautomatically built on the basis of heuristic search. In their short paper on “Reasoning about Conditional Constraint Specification Problems and Feature Models” Raphael Reprint requests to: Alexander Felfernig, Institute for Software Technology, Graz University of Technology, Inffeldgasse 16b, Graz A-8010, Austria. E-mail: alexander.felfernig@ist.tugraz.at Artificial Intelligence for Engineering Design, Analysis and Manufacturing (2011), 25, 113–114. # Cambridge University Press 2011 0890-0604/11