Marco Aurisicchio
Imperial College London, Mechanical Engineering, Faculty Member
Resource flows are generated by integrating production and consumption systems. To achieve circular flows, manufacturers are increasingly collaborating with their stakeholders. Nevertheless, in these collaborations they typically focus on... more
Resource flows are generated by integrating production and consumption systems. To achieve circular flows, manufacturers are increasingly collaborating with their stakeholders. Nevertheless, in these collaborations they typically focus on the interfaces between systems rather than on a more comprehensive implementation of systems thinking principles to achieve deeper integration. This research conceptualises a system called the Resource Flow System (RFS), whose boundaries are defined based on the operational requirement to flow resources circularly. The RFS is intended to be designed by stakeholders through a top-down collaborative approach. A tool called the Flow Mapper (FM) is also introduced. It involves a method to visually model the RFS, and a process to apply the method and analyse the model. Grounded in Systems Thinking, System Dynamics and Material Flow Analysis theories, the tool guides a team to collaboratively develop a visual model of the RFS consisting of a State Model, a Functional Model and a Structural Model. The FM provides a performance-driven focus on the design of solutions for the CE, essential for constructive collaboration and enables users to innovate during system design both by providing them with a model of the system, and by discovering, generating and refining solutions in the process to develop it.
Research Interests:
Consumer goods industries are increasingly incorporating circular practices (e.g. recycling and reuse) into their offerings to reduce environmental impact and combat the issue of waste. The success of these offerings depends on consumers... more
Consumer goods industries are increasingly incorporating circular practices (e.g. recycling and reuse) into their offerings to reduce environmental impact and combat the issue of waste. The success of these offerings depends on consumers significantly changing their behaviour across the journey of purchase, use and disposal. There are a number of unique features that demarcate circular behaviour from other types of consumer behaviour, such as the fact that consumers must operate within a system of interconnected elements to enable resources to flow continuously. However, research to date has applied methodological approaches and behaviour models in a way that only addresses a fraction of the picture. In moving beyond this reductive framing of circular behaviour, a systems thinking framework is introduced, integrating circular behaviour research. The framework is applied to a case example and preliminary findings are presented, which highlight the capability of the proposed framework to explain broad and deep data on circular consumer behaviour. This can be used to pinpoint specific problems in an interconnected chain of behaviours, understand how system elements can cause unintended behavioural consequences, highlight barriers and opportunities to circularity and develop more informed intervention strategies.
Research Interests:
Within the circular economy, the Product-Service System (PSS) is a key business model to slow down and dematerialise resource consumption between manufacturers or service providers and customers. Material-Service Systems (MSSs) have been... more
Within the circular economy, the Product-Service System (PSS) is a key business model to slow down and dematerialise resource consumption between manufacturers or service providers and customers. Material-Service Systems (MSSs) have been proposed as a business model to develop the performance economy focusing on the relationship between material suppliers and manufacturers. The aim of this research is to introduce and develop the MSS concept and to apply it to a real-world case study. The research involved two stages. First, a modelling method is proposed to represent the flow, transformation and ownership of resources by the stakeholders in a supply chain. Second, the method is tested using steel industrial drums as a case. The results indicate that the MSS has the potential to radically transform the steel drums industry and it could work effectively with a PSS within a reuse system to recondition and reintroduce obsolete drums into the market.
Research Interests:
Fast-Moving Consumer Goods (FMCGs) are products that are purchased and consumed frequently to satisfy continuous consumer demand. In a linear economy, FMCGs are typically offered as single-use and disposable products. Limitations in... more
Fast-Moving Consumer Goods (FMCGs) are products that are purchased and consumed frequently to satisfy continuous consumer demand. In a linear economy, FMCGs are typically offered as single-use and disposable products. Limitations in product design, insufficient collection systems, and inefficient recovery processes prevent high recycling rates. As a result, FMCGs often end up in landfill or the environment, contributing to waste accumulation, and pollution. Whilst recycling is the most common waste prevention strategy practiced by the industry, the process is limited to addressing only the final stage of the product life cycle, omitting the overproduction and consumption
of materials typical of FMCGs. Instead, reuse is a strategy that is capable of extending the value of resources by slowing material flows. Novel reuse models that require the consumer to interact with
durable primary packaging and products are emerging in the FMCG industry. However, the constituent elements and operation principles of such reuse models are not fully understood. The aim of this
research is to develop a comprehensive characterisation of reuse models and to evaluate their potential to deliver environmental value. Method: Ninety-two reuse offerings were selected and analysed to
identify their reuse system elements. The analysis led to the identification of a framework including five reuse models, which were also evaluated to establish their capability to deliver environmental value
when compared to conventional single-use and disposable FMCGs. Results: Currently in the FMCG sector, reusable products are mostly durable packaging, such as bottles and containers for beverages,
foods, personal and home care goods, and are infrequently durable products, such as personal and baby care goods, including razors and nappies. Three reuse models involve exclusive reuse, a behaviour by
which a reusable product is used and kept by a single user throughout the product lifetime. In exclusive reuse models, users are provided with either a reusable product (model 1), a reusable product with
preparation for reuse infrastructure (model 2), or access to preparation for reuse infrastructure (model 3). Two reuse models involve sequential reuse, a behaviour by which a reusable product is used by multiple
users throughout the product lifetime and returned after each use to a provider. In sequential reuse models, users are provided with either a reusable product with preparation for reuse infrastructure and
provider-operated recovery services (model 4), or a reusable product and provider-operated services for recovery and preparation for reuse (model 5). Whilst the five reuse models can operate standalone, some offerings were found to embed a multi-model approach. Both exclusive and sequential reuse models are capable of delivering environmental value by reducing the use of natural resources and retaining their value in the economy. In particular, sequential reuse models were found to have a greater capability to increase the share of recyclable resources by offering access to infrastructure for the closure of material
loops. Conclusions: Consumers can currently access five reuse models and choose between exclusive and sequential reuse behaviours. When adopted in conjunction with recycling, reuse models can enable
a more efficient consumption of FMCGs. Providing the infrastructure necessary to enable reuse and recycling is key to the successful and sustainable deployment of the reuse models.
of materials typical of FMCGs. Instead, reuse is a strategy that is capable of extending the value of resources by slowing material flows. Novel reuse models that require the consumer to interact with
durable primary packaging and products are emerging in the FMCG industry. However, the constituent elements and operation principles of such reuse models are not fully understood. The aim of this
research is to develop a comprehensive characterisation of reuse models and to evaluate their potential to deliver environmental value. Method: Ninety-two reuse offerings were selected and analysed to
identify their reuse system elements. The analysis led to the identification of a framework including five reuse models, which were also evaluated to establish their capability to deliver environmental value
when compared to conventional single-use and disposable FMCGs. Results: Currently in the FMCG sector, reusable products are mostly durable packaging, such as bottles and containers for beverages,
foods, personal and home care goods, and are infrequently durable products, such as personal and baby care goods, including razors and nappies. Three reuse models involve exclusive reuse, a behaviour by
which a reusable product is used and kept by a single user throughout the product lifetime. In exclusive reuse models, users are provided with either a reusable product (model 1), a reusable product with
preparation for reuse infrastructure (model 2), or access to preparation for reuse infrastructure (model 3). Two reuse models involve sequential reuse, a behaviour by which a reusable product is used by multiple
users throughout the product lifetime and returned after each use to a provider. In sequential reuse models, users are provided with either a reusable product with preparation for reuse infrastructure and
provider-operated recovery services (model 4), or a reusable product and provider-operated services for recovery and preparation for reuse (model 5). Whilst the five reuse models can operate standalone, some offerings were found to embed a multi-model approach. Both exclusive and sequential reuse models are capable of delivering environmental value by reducing the use of natural resources and retaining their value in the economy. In particular, sequential reuse models were found to have a greater capability to increase the share of recyclable resources by offering access to infrastructure for the closure of material
loops. Conclusions: Consumers can currently access five reuse models and choose between exclusive and sequential reuse behaviours. When adopted in conjunction with recycling, reuse models can enable
a more efficient consumption of FMCGs. Providing the infrastructure necessary to enable reuse and recycling is key to the successful and sustainable deployment of the reuse models.
Research Interests:
Bringing positive experiences to users is one of the key goals when designing conversational agents (CAs). Yet we still lack an understanding of users' underlying needs to achieve positive experiences and how to support them in design.... more
Bringing positive experiences to users is one of the key goals when designing conversational agents (CAs). Yet we still lack an understanding of users' underlying needs to achieve positive experiences and how to support them in design. This research first applies Self-Determination Theory in an interview study to explore how users' needs of competence, autonomy and relatedness could be supported or undermined in CA experiences. Ten guidelines are then derived from the interview findings. The key findings demonstrate that: competence is affected by users' knowledge of the CA capabilities and effectiveness of the conversation; autonomy is influenced by flexibility of the conversation, personalisation of the experiences, and control over user data; regarding relatedness, users still have concerns over integrating social features into CAs. The guidelines recommend how to inform users about the system capabilities, design effective and socially appropriate conversations, and support increased system intelligence, customisation, and data transparency. CCS CONCEPTS • Human-centered computing~Human computer interaction (HCI)
Research Interests:
Purpose Delays in construction projects are both disruptive and expensive. Thus, potential causes of schedule deviation need to be identified and mitigated. In previous research, delay factors were predominantly identified through surveys... more
Purpose Delays in construction projects are both disruptive and expensive. Thus, potential causes of schedule deviation need to be identified and mitigated. In previous research, delay factors were predominantly identified through surveys administered to stakeholders in construction projects. Such delay factors are typically considered individually and presented at the same level without explicitly examining their sequence of occurrence and interrelationships. In reality, owing to the complex structure of construction projects and long execution time, non-conformance to schedule occurs by a chain of cascading events. An understanding of these linkages is important not only for minimising the delays, but also for revealing the liability of stakeholders. To explicitly illustrate the cause-effect and logical relationship between delay factors and further identify the primary factors which possess the highest significance toward the overall project schedule delay, the fault tree analysis (FTA) method, a widely implemented approach to root cause problems in safety-critical systems, has been systematically and rigorously executed. Design/methodology/approach Using a case study, the in-depth analysis for identifying the most fundamental delay factors has been fulfilled through FTA's tree structure. The logical deduction for mapping and visualising the chronological and cause-effect relationships between various delay factors have been conducted through the logical gate functions of FTA based on the data collected from the site event log, prefabricated structural component manufacturing log and face-to-face interview with project stakeholders. Findings The analysis identified multiple delay factors and showed how they are linked logically and chronologically from the primary causes to the ultimate undesired event in a rigorous manner. A comparison was performed between the proposed FTA model and the conventional investigation 1 method for revealing the responsibility employed in the construction industry, consisting of event logs and problem reports. The results indicate that the FTA model provides richer information and a clearer picture of the network of delay factors. Importantly, the ability of FTA in revealing the causal connection between the events leading to the undesired delays and in comprehending their prominence in the real-world construction project have been clearly displayed. Originality/ value This study demonstrates a new application of FTA in the construction sector allowing the delay factors to be understood and visualised from a new perspective. The new approach has practical use in finding and removing root causes of the delay, as well as clarifying the attribution of responsibility that causes the delay.
Research Interests:
Fast-moving consumer goods (FMCGs) comprise products that are bought frequently at a low cost in sectors such as food, health care, beauty and grooming. The single-use nature of most FMCGs means that they are thrown away regularly and... more
Fast-moving consumer goods (FMCGs) comprise products that are bought frequently at a low cost in sectors such as food, health care, beauty and grooming. The single-use nature of most FMCGs means that they are thrown away regularly and sent to landfill or incinerated. Circular practices offer an opportunity to combat these outcomes. Whilst traditional recycling schemes are offered at scale, reuse is being recognised as a practice to further increase the utility of materials. To operate successfully, consumers are expected to perform both recycling and reuse behaviours in ever more complex and fluid ways. However, the literature disproportionately focuses on recycling over reuse, often discusses the two concepts separately, and does not adequately address the unique behaviours related to FMCGs. Therefore, a more nuanced understanding of the literature and a thorough break down of recycling and reuse behaviours is needed. This integrative review was conducted in two-stages. First, an online search identified eight different model categories of recycling and reuse offered for FMCGs, and each were defined by key enabling behaviours. Second, a literature search was conducted and selected papers were allocated to the categories of a new framework, synthesising the literature on recycling and reuse. The framework confirms the predominance of recycling in the literature and identifies three transformations that are taking place: (1) reuse of durable FMCGs is integrating service-based offerings, (2) reuse is taking on the features of recycling, and (3) recycling schemes are diversifying. Further research is needed to create deeper understanding of each of the recycling and reuse models.
Research Interests: Sustainable Production and Consumption, Packaging, Recycling, Waste recycling, Consumer Behavior, and 15 morePackaging Design, Design For Sustainable Behaviour, Environmental Sustainability, Green Consumer Behavior, Design for Behaviour Change, Sustainable Design, Consumer Research, Sustainable Supply Chain, Consumer Psychology, Consumer Goods, Consumer, Marketing strategy in FMCG, Circular Economy, FMCG industry, and FMCG Sector
Reuse systems require consumers to embrace new ways of acquiring, using and disposing of fast-moving consumer goods (FMCGs). In these systems, consumers have to perform chains of diverse behaviours. To date, the literature has focused on... more
Reuse systems require consumers to embrace new ways of acquiring, using and disposing of fast-moving consumer goods (FMCGs). In these systems, consumers have to perform chains of diverse behaviours. To date, the literature has focused on understanding reuse as an individual circular behaviour, neglecting the behaviour chains within which it occurs. A deeper understanding of how behaviour chains are performed is a prerequisite to the successful design of circular FMCGs consumption systems. This research maps behaviour chains occurring within the consumption phase of twenty business-to-consumer reuse systems operating in the FMCGs sector. The chains have been constructed using data on behaviour extracted from user instructions and were studied within the broad context of product reuse offerings. This has enabled the identification of six key attributes of behaviour chains: 1) paths; 2) directions; 3) behaviours; 4) dependencies; 5) levels; and 6) performance indicators. These attributes show that behaviours chains have linear paths but can include forking and colliding points; unfold forward and have a return loop; include primary, secondary and ultimate circular behaviours; have direct and indirect causal dependencies; can be modelled at different levels; and have specific performance indicators. The research provides novel and holistic understanding of how reuse behaviour occurs within circular consumption systems.
Research Interests:
The circular economy is a model of production and consumption to address the relentless depletion of resources and the accumulation of waste. In the circular economy literature, there are sparse suggestions that Product-Service Systems... more
The circular economy is a model of production and consumption to address the relentless depletion of resources and the accumulation of waste. In the circular economy literature, there are sparse suggestions that Product-Service Systems (PSSs) have the potential to produce closed-loop resource flows. This study explored this potential using a systematic literature review focused on the use phase and obsolescence. We identified twenty-one PSS elements that contribute to closed loops and categorised them by six architectural levels, i.e. services, resources, stakeholders, contract, value delivery, and systems and tools. We then structured the PSS elements and their contributions to closed loops under four subfunctions and consolidated them in a novel framework. Intercepting and transitioning obsolete resources are subfunctions demanded by a PSS to achieve an operational solution. Stating and governing resource lifetime are subfunctions wanted by a PSS to improve the solution. The results call for a functional approach to PSS design and consideration of obsolescence of products, components and materials. The implications of the results are that PSS elements contribute to achieving circularity by satisfying specific subfunctions and the data in the framework provide a basis for selecting suitable PSS elements.
Research Interests:
After the depletion of their consumable components, Fast-Moving Consumer Goods (FMCGs) become obsolete. In an attempt to close the loop of resources (i.e. products, components or materials) FMCGs can be designed with revalorisation... more
After the depletion of their consumable components, Fast-Moving Consumer Goods (FMCGs) become obsolete. In an attempt to close the loop of resources (i.e. products, components or materials) FMCGs can be designed with revalorisation services. In these product-service systems (PSSs) consumers are assigned a key role in closing the loops of resource flows. To understand and define this role, we dissected eighteen examples of PSSs. From this analysis, four dimensions emerged that characterise distinct aspects of the PSSs: the form of obsolescence; the change of resources from obsolete to operative or recoverable; the prerequisite activities required of consumers for revalorisation; and the facilitators of activities (i.e. investments and incentives). These dimensions were used to model four data-driven archetypical roles of consumers named after the interaction between consumers and the resource in the obsolete state, namely keep, bring, consign or abandon obsolete components. The research concluded that revalorisation always takes place in designated locations. The roles that consumers fulfil in closed-loop PSSs involve carrying out activities to position resources in such locations. The roles always come at a cost, but PSSs can be designed to reduce it. PSSs can also be designed to induce a perceivable value of obsolete resources, which can be used to increase role fulfilment. This research presents a comprehensive understanding of the roles of consumers in the specific context of closed-loop FMCGs, identifies tactics to increase the fulfilment of these roles and suggests further research on behaviours and PSSs to understand the roles of other stakeholders in various type of PSSs.
Research Interests: Sustainable Development, Packaging, Product Service System, Design For Sustainable Behaviour, Environmental Sustainability, and 14 moreProduct Service Systems, Customer Behaviour, Obsolescence, Closed loop supply chain, Product-Service Systems, Marketing strategy in FMCG, Circular Economy, FMCG Sector and brand preference, FMCG industry, Planned Obsolescence, Sustainable Behaviours, Consumer Behaviour, FMCG Sector, and Obsolescence Programmée
In current supply chains, material suppliers sell raw material resources to producers who sub-sequentially sell produced resourced to consumers. Ownership of resources, therefore, shifts from a few organisations to many consumers who are... more
In current supply chains, material suppliers sell raw material resources to producers who sub-sequentially sell produced resourced to consumers. Ownership of resources, therefore, shifts from a few organisations to many consumers who are responsible to deal with them at the end of life. Product-service systems are business models where producers retaining ownership of produced resources have increased control on obsolete resources. Motivated by the need to facilitate an unlimited use of materials and eliminate waste, this research has introduced the concept of material-service systems, which are business models where material suppliers offer materials as a service to product producers. These systems offer the advantage that material suppliers are in control of resources and are incentivized to revalorise them. A scenario is explored in which a material-service system operates in conjunction with a product-service system and one in which it functions on its own. Finally, the benefits and incentives of the proposed service systems are discussed along with potential enablers and challenges.
Research Interests:
Product-service systems (PSSs) are advocated consumption models in a Circular Economy as they have potential to reduce consumption’s dependency on resources. We proposed a set of guidelines to design PSSs that facilitate closed resource... more
Product-service systems (PSSs) are advocated consumption models in a Circular Economy as they have potential to reduce consumption’s dependency on resources. We proposed a set of guidelines to design PSSs that facilitate closed resource loops. The guidelines can be used to design PSSs that state and govern lifetime which improves the likelihood to establish a resource flow; enable the planning of flows; and can be used to optimise the value of resources. The guidelines also guide the design of PSSs that intercept and transition obsolete resources which is necessary and vital to close resource loops. This work starts to outline an agenda for research on obsolescence, take-back schemes and resource value in the context of closed-loop PSSs.
Research Interests:
While previous studies of Conversational Agents (e.g. Siri, Google Assistant, Alexa and Cortana) have focused on evaluating usability and exploring capabilities of these systems, little work has examined users’ affective experiences. In... more
While previous studies of Conversational Agents (e.g. Siri,
Google Assistant, Alexa and Cortana) have focused on evaluating
usability and exploring capabilities of these systems,
little work has examined users’ affective experiences. In this
paper we present a survey study with 171 participants to
examine CA users’ affective experiences. Specifically, we
present four major usage scenarios, users’ affective responses
in these scenarios, and the factors which influenced the affective
responses. We found that users’ overall experience was
positive with interest being the most salient positive emotion.
Affective responses differed depending on the scenarios.
Both pragmatic and hedonic qualities influenced affect. The
factors underlying pragmatic quality are: helpfulness, proactivity,
fluidity, seamlessness and responsiveness. The factors
underlying hedonic quality are: comfort in human-machine
conversation, pride of using cutting-edge technology, fun
during use, perception of having a human-like assistant, concern
about privacy and fear of causing distraction.
Google Assistant, Alexa and Cortana) have focused on evaluating
usability and exploring capabilities of these systems,
little work has examined users’ affective experiences. In this
paper we present a survey study with 171 participants to
examine CA users’ affective experiences. Specifically, we
present four major usage scenarios, users’ affective responses
in these scenarios, and the factors which influenced the affective
responses. We found that users’ overall experience was
positive with interest being the most salient positive emotion.
Affective responses differed depending on the scenarios.
Both pragmatic and hedonic qualities influenced affect. The
factors underlying pragmatic quality are: helpfulness, proactivity,
fluidity, seamlessness and responsiveness. The factors
underlying hedonic quality are: comfort in human-machine
conversation, pride of using cutting-edge technology, fun
during use, perception of having a human-like assistant, concern
about privacy and fear of causing distraction.
Research Interests:
Maps are visual design representations used by engineers to model the information behind a design. This paper evaluates the application of mapping methods supported by the Decision Rationale editor (DRed) in aerospace engineering... more
Maps are visual design representations used by engineers to model the information behind a design. This paper evaluates the application of mapping methods supported by the Decision Rationale editor (DRed) in aerospace engineering industry. Specifically, the research investigates what DRed mapping methods are used, where engineers find them useful and why. DRed was selected because it has been formally embedded in the design processes of the partner company and all engineering staff have access to it. The tool was investigated using semistructured interviews with 14 engineers, each already trained with DRed through their work and representing diverse departments and experience levels. Nineteen use cases were collected, ranging from high-profile, multistakeholder projects to everyday individual work. Collected cases were analyzed for the methods applied, common contexts of use, and reasons for use. The results validate baseline DRed mapping methods to capture design rationale and analyze the root causes of engineering problems. Further, it provides empirical evidence for new DRed mapping methods to manage requirements, analyze functional interactions in complex systems and manage personal information. The contexts where mapping methods are most used involve: system-level information that cuts across subsystem boundaries; irregular intervals between map applications; dealing with loosely structured information; individual use or small team collaborations; and addressing on-going problems. The reasons stated by engineers for using maps focus on engineering design thinking, communication, and planning support. Using empirical evidence of its recurrent use, this research establishes that DRed is a powerful and versatile tool for engineers in industry and its mapping methods aid important and otherwise unsupported work. The range and impact of the use cases found in practice suggest that engineers need better support for work with loosely structured information. Organizations involved in the design of complex systems should make greater use of semiformal, graph-based visual tools like DRed. The understanding of mapping software gained through this research demonstrates a shift in emphasis from the enrichment of the engineering record to the provision of immediate cognitive benefits for engineers. The results also support an incremental, adaptive approach for deploying this emerging class of tools in other organizations.
Research Interests:
The construction sector is currently undergoing a shift from stick-built construction to modular building systems that take advantage of modern prefabrication techniques. Long established in-situ construction practices are thus being... more
The construction sector is currently undergoing a shift from stick-built construction to modular building systems that take advantage of modern prefabrication techniques. Long established in-situ construction practices are thus being replaced by processes imported from the manufacturing sector, where component fabrication takes place within a factory environment. As a result of this transformation, current construction supply chains, which have focused on the delivery of raw materials to sites, are no longer apt and need to make way to new, strengthened, and time-critical logistics systems. The aim of this study is to establish a mathematical model for the optimisation of logistics processes in modular construction covering three tiers of operation: manufacturing, storage and assembly. Previous studies have indicated that construction site delays constitute the largest cause of schedule deviations. Using the model outlined in this paper we seek to determine how factory manufacturing and inventory management should react to variations in the demand on construction sites. A two-stage stochastic programming model is developed to capture all possible demand variations on site. The model was evaluated using a case study from the residential construction sector. The application showed that the model is effective and can serve as decision support to optimise modular construction logistics.
Research Interests:
Unlike stick-built construction projects, structural components in prefabricated construction projects are produced in a factory environment. Thus, similar to manufacturing industries, the productivity of building components fluctuates,... more
Unlike stick-built construction projects, structural components in prefabricated construction projects are produced in a factory environment. Thus, similar to manufacturing industries, the productivity of building components fluctuates, owing to human error and machine malfunction. Since the site demand must always be met, outsourcing manufacturing is employed to supplement the uncertain self-production. Furthermore, storage facility between factory and construction site becomes indispensable because these components are large in size, yielding a three-tier supply chain that is absent in the traditional construction. The objective of this research is to determine the most appropriate production plan and the optimal outsourcing quantities for multi-prefabricated components under this context. A workflow which includes a two-stage stochastic programming model and a mixed integer linear programming model is established for solving the above issues. Also, the most favourable schemes for distributing components and the variation of inventory are also disclosed. An infrastructure built through prefabrication method has been chosen as a case study for validation.
Research Interests:
In construction projects delays are not only disruptive but also expensive. Thus, the reasons for schedule deviation need to be identified. The delay factors determined in previous research were predominantly studied through surveys. In... more
In construction projects delays are not only disruptive but also expensive. Thus, the reasons for schedule deviation need to be identified. The delay factors determined in previous research were predominantly studied through surveys. In these studies, the participants were stakeholders in construction projects, and the reasons for schedule deviation were identified through their point of view. In addition, delay factors are typically considered individually and are presented at the same level. In reality, owing to the complex structure of construction projects and long execution time, non-conformance in schedules occurs by a chain of events. The aim of this research is to investigate the factors causing schedule deviation in construction projects and understand the cause-effect relationships between the events leading to delays. Among various techniques developed to root cause problems, fault tree analysis (FTA) is an established tool. FTA looks deeply into the chain of events leading to a problem to identify its primary cause. FTA was applied to a modular construction project that experienced significant delays. The analysis identified multiple delay factors, and showed how they are linked from the primary causes to the ultimate event. The root of most delays was traced to the inexperience of the project stakeholders.
Research Interests:
The construction sector is currently undergoing a shift from stick-built construction techniques to modular building systems. If construction supply chains are to support this transformation, they need to be modified and strengthened... more
The construction sector is currently undergoing a shift from stick-built construction techniques to modular building systems. If construction supply chains are to support this transformation, they need to be modified and strengthened using an adapted logistics system. The aim of this study is to establish a mathematical model for the logistics of modular construction covering the three common tiers of operations: manufacturing, storage and construction. Previous studies have indicated that construction site delays constitute the largest cause of schedule deviations. Using the model outlined in this paper we seek to determine how factory manufacturing and inventory management should be adapted to variations in demand on the construction site. We propose a Mixed Integer Linear Programming model that captures construction scenarios with demands for modular products that are either foreseeable or abruptly disrupted. The use of the model is illustrated through a case study of bathroom pods for a building project. The model outputs include supply chain configurations that reduce total costs across a range of scenarios. The model could serve as a decision support tool for modular construction logistics.
Research Interests:
Keeping a product offering in the system through continued use and between multiple users creates the potential for interactions which become contaminated. These contaminated interactions can cause a barrier to material circulation and... more
Keeping a product offering in the system through continued use and between multiple users creates the potential for interactions which become contaminated. These contaminated interactions can cause a barrier to material circulation and extended product lifetimes. This study seeks to identify the underlying design strategies useful in addressing contaminated interaction. Strategies were identified through an exploration of possible solutions to negative contamination in two phases. Phase I involved identifying 70 existing solutions to instances of negative contaminated interaction and abstracting these to identify a more fundamental underlying principle. In Phase II, designers participated in a brainstorming session to identify as many solutions as possible to several contaminated interaction design briefs. The resulting 155 solutions were analysed together with the other data to generate a final set of strategies. In the end, eight strategies distilled from the analysis which are used to address contaminated interaction. The strategies represent preventative and responsive solutions applicable to various elements of the contamination process.
Research Interests:
The study of happiness is receiving increasing attention both in positive psychology and design. A key issue in current literature is the lack of empirical evidence linking products and happiness. We address this examining 87 reports of... more
The study of happiness is receiving increasing attention both in positive psychology and design. A key issue in current literature is the lack of empirical evidence linking products and happiness. We address this examining 87 reports of product-mediated happy experiences and analysing their relations to well-being. Six types of products with experiential attributes were reported to contribute more systematically to happiness. Digital devices and food are the two dominant products followed by vehicles, books, clothing & accessories and sport equipment. These products make us happy by creating: hedonic experiences in which we relieve stress, get rest and increase joy; and eudaimonic experiences in which we establish positive social relationships, develop self-identity, achieve personal growth and gain competence and autonomy. In such experiences, products acted as carriers of reflective meanings, and enablers of experiencing. These insights provide an initial mapping of the relationship between products and happiness and suggest approaches to designing products that can bring happy experiences.
Research Interests:
This paper describes some research stimulated by a fundamental shift that is occurring in the manufacture and marketing of aero engines for commercial and defence purposes, away from the selling of products to the provision of services.... more
This paper describes some research stimulated by a fundamental shift that is occurring in the manufacture and marketing of aero engines for commercial and defence purposes, away from the selling of products to the provision of services. The collaborating aerospace company offers contracts under which it remains responsible for the maintenance of engines which have been purchased by airlines through these contracts based on payment for usage. This has triggered a major re-assessment of the design of aero engines to reduce their overall life cycle costs, while maintaining performance efficiency. In this context, the use of in-service experience of existing engines is important in the design of components and systems of a new engine, to tackle in-service issues through design and thus to reduce maintenance costs and increase reliability. This paper aims at identifying designers’ requirements regarding in-service information. Semi-structured interviews with designers from an aerospace company were conducted; after these interviews, the designers were requested to comment on a set of questions regarding in-service information, indicating how frequently they might ask each of them when designing a new component or system. In addition, some documents containing the in-service information considered by the designers in designing components and systems of a new engine were analysed. The results indicate what in-service information is required by designers for this new task.
Research Interests:
In the global market of air transport, integration of products and services is now seen as being necessary for the long-term success of engine manufacturers. This paper describes research stimulated by a fundamental shift that is... more
In the global market of air transport, integration of products and services is now seen as being necessary for the long-term success of engine manufacturers. This paper describes research stimulated by a fundamental shift that is occurring in the manufacture and marketing of aero engines for commercial and defence purposes, away from the selling of products to the provision of services. Our collaborating aerospace company now offers TotalCare TM contracts, under which it leases engines to airlines while remaining responsible for their maintenance. The aims of our ongoing research are to: (1) understand the current flows of in-service information to designers; (2) understand the in-service information requirements of designers; (3) develop, based on this understanding, the most appropriate theories and methods to support designers in their new task. The work presented in this paper aims at understanding the use of in-service information in a design task by examining the executed desi...
This research is triggered by the emerging 'power by the hour'® paradigm, in which aero engines are effectively leased to airlines, with the manufacturing company remaining responsible for their maintenance and repair throughout... more
This research is triggered by the emerging 'power by the hour'® paradigm, in which aero engines are effectively leased to airlines, with the manufacturing company remaining responsible for their maintenance and repair throughout their service life. By incorporating knowledge about the performance of existing products into the design phase of new products, it is hoped to tackle some of the in-service problems at the design stage. In the aerospace sector, it is standard design practice to utilise the experience gained from past projects, but that from in-service has not been given sufficient attention. In this context, the aims of our ongoing research are: (1) to understand the current flows of in-service information to designers; (2) to understand the in-service information requirements of designers; (3) to develop the most appropriate theories and methods to support designers in their new task of creating engines which will perform reliably and economically throughout their ...
This research is triggered by a fundamental shift that is occurring in the manufacture and marketing of aero engines for commercial and defence purposes, away from the selling of products to the provision of services. Under the emerging... more
This research is triggered by a fundamental shift that is occurring in the manufacture and marketing of aero engines for commercial and defence purposes, away from the selling of products to the provision of services. Under the emerging 'power by the hour' paradigm, aero engines are effectively leased to the airlines, with the manufacturing company remaining responsible for their maintenance and repair throughout their service life. This has triggered a major re-assessment of the design of aero engines to reduce their overall life-cycle costs, while maintaining performance efficiency. The important aims of our ongoing research are: firstly to understand the current flows of in-service information to designers; secondly to understand the information requirements of designers about in-service issues; thirdly to develop the most appropriate theories and methods to support designers in their new task. This paper presents the results of the initial phase of an ongoing research pr...
A steady stream of research in user experience (UX) has been produced over the last ten years. However, published work has not been reviewed and analysed to synthesise the knowledge developed. To address this issue, this article presents... more
A steady stream of research in user experience (UX) has been produced over the last ten years. However, published work has not been reviewed and analysed to synthesise the knowledge developed. To address this issue, this article presents a review of theories, models and frameworks of UX from different disciplines. Based on the review a scenario in which user experience develops is proposed. Four elements have been identified that have a strong impact on user experience: the user, the interaction, the artefact, and the context. Each element is reviewed in detail, outlining its major characteristics.
Research Interests:
In this paper we introduce two tools and describe a process to design for distinct positive emotions. The tools offer detailed knowledge of three emotions: anticipation, confidence, and inspiration. Eighteen product and interaction... more
In this paper we introduce two tools and describe a process to design for distinct positive emotions. The tools offer detailed knowledge of three emotions: anticipation, confidence, and inspiration. Eighteen product and interaction designers participated in a design workshop in which they applied the proposed tools and process. Participants evaluated the tools and process with a questionnaire and in a group discussion. They reported that the tools helped them to structure their process when designing for positive emotions: the tools and process had an impact on the way in which they generated ideas, their understanding of the emotions, the way in which they reasoned their design decisions, and how they saw the user.
Research Interests:
This study reports qualitative research about how users experience great products. Eighteen interviews were conducted in which participants were asked to bring along a ‘great’ product that they own. During the interviews participants... more
This study reports qualitative research about how users experience great products. Eighteen interviews were conducted in which participants were asked to bring along a ‘great’ product that they own. During the interviews participants explained why they consider a product great and how they experience it. The experiences were categorised in two groups: ‘pragmatic experience’, and ‘significant experience’. The term pragmatic refers to a utilitarian view of the human-product interaction, while the term significant stresses the suitability of the product for users including, their personal benefit and growth. In the paper the two experiences are explained in detail, including the needs fulfilled and the emotions elicited by the products.
Research Interests:
This study reports quantitative research into two basic dimensions of emotions: pleasantness and arousal. Fifty-nine participants evaluated these two dimensions for a set of twenty-five positive emotions in relation to human-product... more
This study reports quantitative research into two basic dimensions of emotions: pleasantness and arousal. Fifty-nine participants evaluated these two dimensions for a set of twenty-five positive emotions in relation to human-product interactions. Three levels of arousal were iden- tified: ‘exciting’, ‘median’ and ‘calm’. Nine emotions were found to be exciting, namely energetic, euphoria, amusement, desire, joy, love, inspiration, lust and surprise. Ten emotions were found to be median in arousal, namely fascination, satisfaction, confidence, pride, anticipation, enchant- ment, courage, hope, worship and admiration. Six emotions were found to be calm, namely relaxation, relief, kindness, dreaminess, respect and sympathy. Three levels of pleasantness were also identified: ‘very pleasant’, ‘mildly pleasant’ and ‘pleasant’. Six emotions were found to be very pleasant, namely amusement, joy, satisfaction, inspiration, euphoria and love. Thirteen emotions were found to be mildly pleasant, namely relief, relaxation, kindness, dreaminess, con- fidence, fascination, pride, enchantment, anticipation, energetic, desire, lust and surprise. Finally six emotions were found to be pleasant, namely respect, sympathy, admiration, courage, hope and worship. The results of this study can guide designers to define the emotional tone of the user experience that they are aiming for.
Research Interests:
The mental state in which an individual claims an object as theirs is called psychological ownership. Psychological ownership is associated with motives, routes, affordances, and outcomes directly linked to attachment. This research... more
The mental state in which an individual claims an object as theirs is called psychological ownership. Psychological ownership is associated with motives, routes, affordances, and outcomes directly linked to attachment. This research introduces psychological ownership in the context of designing object attachment and identifies affordance principles that help facilitate it. A framework presenting the motives for and routes to psychological ownership is proposed to provide a holistic understanding of object attachment. In the framework each route to psychological ownership, that is, control, intimate knowledge, and self-investment, has a corresponding class of affordances. Overall a total of 16 affordance principles are identified through contextual inquiry with 4 objects (a car, a mobile phone, a pair of shoes, and a park bench). Previous studies have identified various elements of this framework but have fallen short of clearly defining and relating the motives, routes, and affordances to psychological ownership identified here. These affordance principles are readily mapped to experience design models and provide a practical resource for designers. Together, the framework and the affordances inform design decisions and move towards a prescriptive design method for facilitating object attachment.
Research Interests:
Materials help communicate meaning to users. This meaning changes with time as the object transforms due to use. Through a two-phase study, this research develops new understanding of how people appraise used objects and the mechanisms... more
Materials help communicate meaning to users. This meaning changes with time as the object transforms due to use. Through a two-phase study, this research develops new understanding of how people appraise used objects and the mechanisms driving contamination—the aversion that one has towards engaging with used objects. In the first phase, observations of indicators of use were collected from participants in order to develop a general typology for indicators of use and deduce the sensorial properties of used objects. In the second phase, these observations were analysed to isolate the data, which caused feelings of aversion. The subset of observations marked with aversion was labelled as contaminated. Further analysis revealed three mechanisms driving contamination—hygiene, utility, and territory—presented together as the HUT contamination model. Sensorial properties from the first study were mapped to contamination mechanisms and properties most frequently contributing to contamination were identified. The properties contributing to the various contamination mechanisms differ significantly. Hygienic contamination typically results from transient object states, utility contamination from permanent changes to object characteristics, and territorial contamination from object settings and contextual factors. As expected, the majority of the indicators contributing to contamination are related to material properties. This work acts as a link between material selection and contaminated interaction with used objects.
Research Interests:
This paper reports semi-qualitative research on emotions from the perspective of users and designers. Twenty-five positive emotions were ranked regarding four relevant issues for product design: frequency of experience, preference for... more
This paper reports semi-qualitative research on emotions from the perspective of users and designers. Twenty-five positive emotions were ranked regarding four relevant issues for product design: frequency of experience, preference for experience, preference for elicitation, and difficulty in elicitation. Based on the results from this research the emotions that users frequently experience and prefer are: satisfaction, inspiration, confidence, joy, amusement, and relaxed. These emotions ranked high also among those that designers prefer to elicit. Emotions that are infrequently experienced and not preferred by both users and designers are: lust and worship. In relation to the difficulty of eliciting positive emotions through durable products, the conclusion is that it is a challenging task and little knowledge exists to support designers. The knowledge developed through this project is expected to be useful for designers and researchers to understand the role of positive emotions in product design.
Research Interests:
Research Interests:
Research Interests:
Efforts promoting proper disposal of packaging generally focus on infrastructure and messaging. Significantly less attention has been given to how the attributes of packaging can be used to change disposal behaviour. This research shows... more
Efforts promoting proper disposal of packaging generally focus on infrastructure and messaging. Significantly less attention has been given to how the attributes of packaging can be used to change disposal behaviour. This research shows how changes in packaging attributes (e.g. alterations in shape, colour, or size) influence two disposal behaviours: recycling and littering. Specifically, we use an implicit association test to measure the subconscious tendency to categorize altered objects as trash rather than recycling. The results indicate that 82% of respondents showed at least a slight effect and 53% showed a strong effect towards associating altered objects with waste. Next, we evaluate object transformations on littering behaviour through an observational field study. Observations (N = 2823) indicated that littering is influenced by deformed, torn, disassembled, and partially full packaging. No significant effect was found with regard to packaging that is wet, sticky, has undergone colour changes or that is has remains (e.g. sauce) on it. These findings suggest that the (re)design of packaging can significantly influence proper disposal. Based on this, packaging can be (re)designed in two ways. First, many types of packaging have scripted alterations such as the iconic ‘tear here’ indicator. These can be changed to preserve properties associated with recyclables and non-littering. Second, packaging can be designed so that there are fewer alterations during use. This work can also help identify inherent attributes that encourage proper disposal.
Research Interests:
Keywords: Root Cause Analysis (RCA) Argument-based rationale Issue Based Information System (IBIS) Functional modelling Function Analysis Diagram (FAD) Space Shuttle Challenger disaster a b s t r a c t Objective: The process of... more
Keywords: Root Cause Analysis (RCA) Argument-based rationale Issue Based Information System (IBIS) Functional modelling Function Analysis Diagram (FAD) Space Shuttle Challenger disaster a b s t r a c t Objective: The process of understanding the causes of adverse events associated with complex engineered systems can be time consuming and expensive. It often requires substantial human and physical resources ranging from a few engineers up to multiple teams of domain specialists from collaborating organisations. The research presented in this article aims to provide more effective support to the analysts involved in root cause analysis (RCA) by exploring the combined application of the Issue Based Information System (IBIS) and the Function Analysis Diagram (FAD) methods. The first method (IBIS) introduces the concept of argument-based rationale for explicit justification of the nodes of a cause– effect chain as well as of redesign decisions, while the second method (FAD) introduces the notion of structure-dependent functional modelling of complex systems in normal and failure states. Method: Causation data from publicly available technical reports of the Space Shuttle Challenger disaster was reverse-engineered using a root cause analysis approach based on the IBIS and FAD notations. IBIS and FAD were implemented using a free and open source software tool known as designVUE. The approach was evaluated by comparing it to a method for root cause analysis widely used in industry and assessing how it satisfies generic requirements for root cause analysis. Results: The results show that the proposed IBIS-FAD approach provides a rich description of the causes for an accident presented in a manner that facilitates information access and understanding. The IBIS notation allowed for explicit modelling of the reasons supporting or refuting failure hypotheses along with evidence. The FAD notation provided a clear and concise method to visualise the complex set of non-linear interactions leading to the failure of a system by annotating graphical schematics of the design with the functions exchanged between its components. Finally, the results show that the approach supports the capture and justification of redesign decisions and ties them to initiating problems in a way that promotes the prevention of accident re-occurrence. Conclusions: Argument-based rationale with IBIS and FAD-style functional modelling are powerful concepts to extend the tool set available to support the root cause analysis process. The approach proposed in this article provides a unique tool that would be of value to academics, practitioners, and regulators concerned with root cause analysis and opportunities to improve the process of understanding adverse events.
Research Interests:
This study explores the extent to which the theory of psychological ownership can be used to understand and design for slower consumption through two strategies: product longevity and access-based consumption. To do this we employ a... more
This study explores the extent to which the theory of psychological ownership can be used to understand and design for slower consumption through two strategies: product longevity and access-based consumption. To do this we employ a qualitative study investigating objects kept, discarded and used by participants. We find that the theory is useful in informing both product longevity research and access-based consumption. Both strategies benefit from a framework in which the motives and routes to developing object attachment are discussed. Longevity decisions made by users (i.e. keeping, disposing and engaging with objects) are determined by the ability of an object to fulfill the motives in the framework. Routes can be utilized to create more meaningful paths to ownership and attachment. Access-based consumption threatens all three motives for ownership and leaves the user with little meaning. Thus the theory helps explain the consumer reluctance to adopt access-based consumption models as they currently stand.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
This paper presents the results of developing and evaluating an automatic approach that identifies causality boundaries from causality expressions. This approach focuses on explicitly expressed causalities extracted from Root Cause... more
This paper presents the results of developing and evaluating an automatic approach that identifies causality boundaries from causality expressions. This approach focuses on explicitly expressed causalities extracted from Root Cause Analysis (RCA) reports in engineering domains. Causality expressions contain Cause and Effect pairs and multiple expressions can occur in a single sentence. Causality boundaries are semantically annotated text fragments explicitly indicating which parts of a fragment denote Causes and corresponding Effects. To identify these, linguistic analysis using natural language processing (NLP) is required. Current off-the-shelf NLP tools are mostly developed based on the language models of general-purpose texts, e.g. newspapers. The lack of portability of these tools to engineering domains has been identified as a barrier to achieving comparable analysis accuracy in new domains. One of the reasons for this is the rare and unpredictable behaviours of certain words in closed domains. Ill-formed sentences, abbreviations and capitalization of common words also contribute to the difficulty. The proposed approach addresses this problem by using a probability-based method that learns the probability distribution of the boundaries not only from the NLP analysis but also from the local contexts that exploit language conventions occurred in the RCA reports. Using a collection of RCA reports obtained from an aerospace company, a test showed that the proposed approach achieved 86% accuracy outperforming a baseline approach that relied only on the NLP analysis.