CAFixD: A Case-based Reasoning Method for Fixture Design

Fixtures accurately locate and secure a part during machining operations such that the part can be manufactured to design specifications. To reduce the design costs associated with fixturing, various computer-aided fixture design (CAFD) methods have been developed through the years to assist the fixture designer. Much research has been directed towards developing systems that determine an optimal fixture plan layout, but there is still a need to develop a CAFD method that can continue to assist designers at the unit level where the key task is identifying the appropriate structure that the individual units comprising a fixture should take. This research work details the development of a CAFD methodology (called CAFixD) that seeks to fill this hole in the CAFD field. The approach taken is to consider all operational requirements of a fixture problem, and use them to guide the design of a fixture at the unit level. Based upon a case-based reasoning (CBR) methodology where relevant design experience is retrieved and adapted to provide a new fixture design solution, the CAFixD methodology adopts a rigorous approach to indexing design cases in which axiomatic design functional requirement decomposition is adopted. Thus, the design requirement is decomposed in terms of functional requirements, physical solutions are retrieved and adapted for each individual requirement, and the design re-constituted to form a complete fixture design. Case adaptation knowledge is used to guide the retrieval process. Possible adaptation strategies for modifying candidate cases are identified and then evaluated. Case and adaptation strategy combinations that result in adapted designs that best satisfy the preferences of the designer are used as the final design solutions. Possible means of refining the effectiveness of the method include combining adaptation strategies and considering the order in which design decisions are taken

A review of methodologies applied in Australian practice to evaluate long-term coastal adaptation options

Rising sea levels have the potential to alter coastal flooding regimes around the world and local governments are beginning to consider how to manage uncertain coastal change. In doing so, there is increasing recognition that such change is deeply uncertain and unable to be reliably described with probabilities or a small number of scenarios. Characteristics of methodologies applied in Australian practice to evaluate long-term coastal adaptation options are reviewed and benchmarked against two state-of-the-art international methods suited for conditions of uncertainty (Robust Decision Making and Dynamic Adaptive Policy Pathways). Seven out of the ten Australian case studies assumed the uncertain parameters, such as sea level rise, could be described deterministically or stochastically when identifying risk and evaluating adaptation options across multi-decadal periods. This basis is not considered sophisticated enough for long-term decision-making, implying that Australian practice needs to increase the use of scenarios to explore a much larger uncertainty space when assessing the performance of adaptation options. Two Australian case studies mapped flexible adaptation pathways to manage uncertainty, and there remains an opportunity to incorporate quantitative methodologies to support the identification of risk thresholds. The contextual framing of risk, including the approach taken to identify risk (top-down or bottom-up) and treatment of uncertain parameters, were found to be fundamental characteristics that influenced the methodology selected to evaluate adaptation options. The small sample of case studies available suggests that long-term coastal adaptation in Australian is in its infancy and there is a timely opportunity to guide local government towards robust methodologies for developing long-term coastal adaptation plans

Price strategies as a determinant of performance on romanian companies in export markets

JEL Classification System: M10- General; L1-Market Structure, Firm Strategy and Market Performance; L11-Production, Pricing and Market StructurePricing strategy is considered to be one of the more critical components of the marketing mix (Product, Place, Price and Promotion) and is focused on generating revenue and ultimately profit for the company. The current research study aims to analyze what pricing strategies Romanian exporting companies use in order to strife for better results. As the study focuses on exporting companies, not only setting one or more pricing strategy is important, but also how do these companies adapt their strategies to different industries and different geographical markets. The applied methodology sustains, that the results are rooted on a case study within the preferred pricing strategies of the analyzed companies. The information towards the research was gathered throughout in-depth interviews with the managers in charge of this process, document analysis and observations. The systematic approach of identifying the most adequate price strategies is opening the path for factors taking in account when adaptation process begins and also for analyzing the impact of pricing adaptation. This can lead to measure the data for export performance and what influence did it had on a company’s turnover. By analyzing the export data provided, a comparison can be made, taking into consideration price strategies used, price adaptation processes, level of impact on different geographical markets, the market response to exported products and terms and conditions necessary for conducting international trad

Are wildcard events on infrastructure systems opportunities for transformational change?

Infrastructure systems face a number of pressing challenges relating to demographics, environment, finance and governance pressures. Furthermore, infrastructure mediates the way in which everyday lives are conducted; their form and function creating a persistence of unsustainable practice and behaviour that cannot be changed even if change is desired. There is a need to find means by which this obduracy can be broken so that new, more sustainable futures can be planned. This paper develops a methodology, taking concepts from both engineering and social science. Wild cards, or physical disruptions, are used to ‘destructively test’ complex infrastructure systems and the multi-level perspective is used as a framework for analysing the resulting data. This methodology was used to examine a number of case studies, and with focus groups consisting of a range of different infrastructure providers and managers, to gain a better understanding of systems’ sociotechnical characteristics and behaviours. A number of impactful ‘intervention points’ emerged that offered the opportunity to promote radical changes towards configurations of infrastructure systems that provide for ‘less’ physical infrastructure. This paper also examines the utility of wild cards as enablers of transition to these ‘less’ configurations and demonstrates how a ‘wild card scenario’ can be used to co-design infrastructure adaptation from with both infrastructure providers and users

Modelling and analyzing adaptive self-assembling strategies with Maude

Building adaptive systems with predictable emergent behavior is a challenging task and it is becoming a critical need. The research community has accepted the challenge by introducing approaches of various nature: from software architectures, to programming paradigms, to analysis techniques. We recently proposed a conceptual framework for adaptation centered around the role of control data. In this paper we show that it can be naturally realized in a reflective logical language like Maude by using the Reflective Russian Dolls model. Moreover, we exploit this model to specify, validate and analyse a prominent example of adaptive system: robot swarms equipped with self-assembly strategies. The analysis exploits the statistical model checker PVeStA

Measuring adaptation to non-permanent employment contracts using a conjoint analysis approach

This study attempts to uncover the ‘real’ impact of temporary contracts on workers’ perceived job quality, prior to the psychological phenomena of adaptation, coping and cognitive dissonance coming into play. This is done by using a novel conjoint analysis approach that examines the ex ante preferences over different contract statuses of a newly generated sample of low-skilled employees from seven European countries. Other things equal, it is shown that the anticipated psychological ‘costs’ of moving from a riskless permanent contract to the insecurity of a temporary job or no work at all appear to be quite significant. In contrast, temporary employees, who have presumably already adapted to the circumstances surrounding a non-permanent contract, are found to be statistically indifferent between permanent and temporary employment, and request much smaller wage premiums in order to switch from one status to the other. The well-documented distress associated with joblessness is also confirmed in our data. The methodology developed here can provide policymakers with an alternative and relatively inexpensive method of quantifying the immediate impact of any shift in their employment policies.European Commissio

Failure is an option:an innovative engineering curriculum

PurposeAdvancements and innovation in engineering design are based on learning from previous failures but students are encouraged to ‘succeed’ first time and hence can avoid learning from failure in practice. The purpose of the study was to design and evaluate a curriculum to help engineering design students to learn from failure.Design/Methodology/ApproachA new curriculum design provided a case study for evaluating the effects of incorporating learning from failure within a civil engineering course. An analysis of the changes in course output was undertaken in relation to graduate destination data covering 2006 to 2016 and student satisfaction from 2012 to 2017 and a number of challenges and solutions for curriculum designers were identified.FindingsThe design and delivery of an innovative curriculum, within typical constraints, can provide opportunities for students to develop resilience to failure as an integral part of their learning in order to think creatively and develop novel engineering solutions. The key issues identified were: the selection of appropriate teaching methods, creating an environment for exploratory learning, group and team assessments with competitive elements where practicable, and providing students with many different pedagogical approaches to produce a quality learning experience.OriginalityThis case study demonstrates how to design and implement an innovative curriculum that can produce positive benefits of learning from failure. This model can be applied to other disciplines such as building surveying and construction management. This approach underpins the development of skills necessary in the educational experience to develop as a professional building pathologist