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Integrating intellectual property and sustainable business models: The SBM-IP canvas
No full textCompanies attempt to address global sustainability challenges through innovating products, services, and business models. This paper focuses on sustainable business model (SBM) innovations as a way to systemically transform businesses towards sustainability. It has been widely recognized that strategic approaches to using intellectual property (IP) need to be aligned with business model innovation for commercial success. Here we suggest that IP, aligned with SBMs, can also be used to create not only commercial, but also societal and environmental impact. Knowledge about how to best align IP with SBMs to drive sustainability transitions remains limited. We address this gap by developing an SBM-IP canvas that integrates IP considerations into each of the SBM canvas building blocks. We do this by employing relevant theoretical concepts from three literature streams, namely the business model (including SBM), IP, and innovation literature. We use case examples to illustrate different IP considerations that are relevant for the SBM-IP building blocks. These examples show that different IP types (e.g., patents, trademarks) and ways of using them (e.g., more or less restrictive licensing) are applied by companies in relation to the different building blocks. While covering new theoretical ground, the proposed SBM-IP canvas can help decision makers understand how they can use different IP types strategically to propose, create, deliver, and capture sustainable value for society, environment, and the business
Reduction of switching time in ZnO nanoparticle-based reflective OASLM for holographic displays
No full textOptically addressed spatial light modulator (OASLM) has attracted an increasing amount of attention due to its enormous potential in digital holography. Solution-processed ZnO nanoparticle (NP) is particularly promising in OASLM as a photosensor because ZnO NP-based OASLM can provide high resolution, large panel size, and economical production cost. However, it is still challenged by slow switching speed due to a long fall time (off time) and it takes tens of seconds for ZnO NP-based OASLM to switch off, which is limiting its application in dynamic digital holography. In this paper, the optimization in the fall time of ZnO NP-based OASLM is presented. The reduction in fall time was achieved by thermal annealing of ZnO NP, which decreases the effect of charge carrier trapping. Moreover, the fall time was further shortened by introducing a SiO2 layer between ZnO NP and liquid crystal layer so that the charge trapping at the interface is weakened. The shortest fall time of 0.99s was achieved in reflective OASLM, incorporating PEDOT:PSS-ZnO NP heterojunction. The heterojunction was also characterized in terms of IV characteristics and its barrier height was measured by CV measurement. The reduction of fall time discussed in this paper is valuable and it makes ZnO NP-based OASLM attractive for dynamic holographic displays
Interaction of void spacing and material size effect on inter-void flow localisation
No full textThe ductile fracture process in porous metals due to growth and coalescence of micron scale voids is not only affected by the imposed stress state but also by the distribution of the voids and the material size effect. The objective of this work is to understand the interaction of the inter-void spacing (or ligaments) and the resultant gradient induced material size effect on void coalescence for a range of imposed stress states. To this end, three dimensional finite element calculations of unit cell models with a discrete void embedded in a strain gradient enhanced material matrix are performed. The calculations are carried out for a range of initial inter-void ligament sizes and imposed stress states characterised by fixed values of the stress triaxiality and the Lode parameter. Our results show that in the absence of strain gradient effects on the material response, decreasing the inter-void ligament size results in an increase in the propensity for void coalescence. However, in a strain gradient enhanced material matrix, the strain gradients harden the material in the inter-void ligament and decrease the effect of inter-void ligament size on the propensity for void coalescence
Deflecting the issue: The origin of nanoscalematerial build-up in continuous inkjet printing
No full textContinuous inkjet printing relies on steering charged droplets accurately to the surface by using electric fields. A vital component is the set of deflecting electrodes within the printhead, which create these fields. Unwanted deposition of ink on the electrodes, known as build-up, is a concern for operators because this modifies the applied electric field, affects long-term reliability, and requires manual intervention. However, this has not been widely reported or explored. Here, the authors report a laser-based high-speed visualization technique to observe build-up and show that it stems from small satellite droplets that break off from the main printed drops. They characterize the material build-up and reveal its nanoscale particulate nature. Combining the tracking with characterization allows quantifying the charge-to-mass ratio of these droplets. This study provides a route to understanding the build-up phenomenon, and it will enable optimization of printing conditions and printing reliability
The effect of aromatic ring size in electron deficient semiconducting polymers for n-type organic thermoelectrics
No full textN-type semiconducting polymers have been recently utilized in thermoelectric devices, however they have typically exhibited low electrical conductivities and poor device stability, in contrast to p-type semiconductors, which have been much higher performing. This is due in particular to the n-type semiconductor's low doping efficiency, and poor charge carrier mobility. Strategies to enhance the thermoelectric performance of n-type materials include optimizing the electron affinity (EA) with respect to the dopant to improve the doping process and increasing the charge carrier mobility through enhanced molecular packing. Here, we report the design, synthesis and characterization of fused electron-deficient n-type copolymers incorporating the electron withdrawing lactone unit along the backbone. The polymers were synthesized using metal-free aldol condensation conditions to explore the effect of enlarging the central phenyl ring to a naphthalene ring, on the electrical conductivity. When n-doped with N-DMBI, electrical conductivities of up to 0.28 S cm-1, Seebeck coefficients of -75 μV K-1 and maximum Power factors of 0.16 μW m-1 K-2 were observed from the polymer with the largest electron affinity of -4.68 eV. Extending the aromatic ring reduced the electron affinity, due to reducing the density of electron withdrawing groups and subsequently the electrical conductivity reduced by almost two orders of magnitude. This journal i
Novel Gramians for linear semistable systems
No full textIn this paper, the notions of pseudo Gramians are introduced for linear time-invariant semistable systems, which allow multiple semisimple poles at the origin. The proposed Gramians are the generalizations of standard Gramian matrices defined for asymptotically stable systems, and they can be computed by a set of Lyapunov equations. Furthermore, it is shown that the controllability and observability of a semistable system are indicated by the ranks of the pseudo Gramians, and the controllability and observability energy functions are also characterized using the pseudo Gramians. Additionally, the H2-norm and H∞-norm of a semistable system are analyzed, and then the results are used for the model reduction of semistable systems. Finally, the effectiveness of the methods is illustrated by an example of a gene regulation network
Effect of transverse gust velocity profiles
No full textA large variety of gusts that develop in the atmospheric boundary layer affect aerial vehicles. This study, performed in water tow tanks, compares the response of a flat plate wing to transverse vertical gusts with a top-hat and a sine-squared velocity profile at Reynolds numbers of 20,000–30,000. Experiments are performed for a wide range of gust ratios (0.5–1.5) and angles of attack (0–20 deg). Force measurements for a sine-squared gust show a smoother increase in lift and a lower peak compared with a top-hat gust for the same gust ratio. Linear models are found to work reasonably well predicting the force response for the sine-squared gust, whereas the top-hat gust exhibits significant nonlinear effects at the largest gust ratios. This nonlinear behavior is linked to high levels of circulation shed from the wing edges and the development of nonplanar wakes. Nevertheless, the gust momentum inflow on the wing is directly linked to many characteristics of the lift response, independently of gust velocity profile. In addition, the lift response for the two gusts is found to increase with angle of attack until the wing inclination is large enough to produce a separated wake before gust entry
A building regulation question answering system: A deep learning methodology
No full textRegulations play an important role in assuring the quality of a building's construction and minimizing its adverse environmental impacts. Engineers and the like need to retrieve regulatory information to ensure a building conforms to specified standards. Despite the availability of search engines and digital databases that can be used to store regulations, engineers, for example, are unable to retrieve information for domain-specific needs in a timely manner. As a consequence, users often have to deal with the burden of browsing and filtering information, which can be a time-consuming process. This research develops a robust end-to-end methodology to improve the efficiency and effectiveness of retrieving queries pertaining to building regulations. The developed methodology integrates information retrieval with a deep learning model of Natural Language Processing (NLP) to provide precise and rapid answers to user's questions from a collection of building regulations. The methodology is evaluated and a prototype system to retrieve queries is developed. The paper's contribution is therefore twofold as it develops a: (1) methodology that combines NLP and deep learning to be able to address queries raised about the building regulations; and (2) chatbot of question answering system, which we refer to as QAS4CQAR. Our proposed methodology has powerful feature representation and learning capability and therefore can potentially be adopted to building regulations in other jurisdictions
Combining LCA and LCC in the early-design stage: A preliminary study for residential buildings technologies
No full textLife Cycle Assessment (LCA) and Life Cycle Costing (LCC) procedures are usually employed during the different building design phases. The first one is mainly related to the environment protection, while the second to the costs control and optimization. This paper aims to define a procedure to “translate” LCA results into an economic evaluation, typical of LCC. The goal is to support the decision-making process in the early-design phase for providing design guidance and monitoring, effectively and timely. This approach can lead to a comparison and choice among different structural technological solutions by focusing both on environmental impacts and on economic costs. LCA and LCC analyses have been carried out evaluating some construction solutions for residential buildings, considering the economic consequence of environmental impact (monetization of carbon emission). This article presents two methods: the first suggests a quantification from an economic point of view the carbon emission during the life cycle of building components through a “carbon tax”; the second one evaluates the “eco-cost” as a Virtual Pollution Prevention Cost (VPPC). Finally, the two methods were applied and compared on a case study, in order to define the possible outcomes on the building construction sector and on public policies
Cyber-physical systems research and education in 2030: Scenarios and strategies
No full text© 2020 Future cyber-physical systems (CPS), such as smart cities, collaborative robots, autonomous vehicles or intelligent transport systems, are expected to be highly intelligent, electrified, and connected. This study explores a focal question about how these new characteristics may affect the education and research related to CPS in 2030, the date identified by the United Nations to achieve the Agenda for Sustainable Development. To this end, first, we have conducted a trend spotting activity, seeking to identify possible influencing factors that may have a great impact on the future of CPS education and research. These factors were clustered in a total of 12 trends – four certainties; namely connectivity, electrification, data and automation – and eight uncertainties; namely intelligence, data ethics, labour market, lifelong learning, higher education, trust in technology, technological development speed, and sustainable development goals. After that, two of the eight uncertainties are identified and used to construct a scenario matrix, which includes four scenarios. These two uncertainties – the so-called strategic uncertainties – are: fulfilment of sustainable development goals and the nature of the technological development, respectively. These two important uncertainties are considered to build the scenarios due to their potential impact on the research and education of CPS. For instance, sustainable development goals are significant targets for many initiatives, organisations and countries. While 2030 is the deadline to achieve these goals, the relationship between the sustainable development goals related to CPS research and education is not studied well. Similarly, the speed of technological development is seen as a driving force behind future CPS. However, the effect of this speed to CPS research and education environment is not known. Different outcomes of the chosen two uncertainties are, then, combined with the remaining trends and uncertainties. Consequently, four scenarios are derived. The Terminator scenario illustrates a dystopian future where profit is the driving force behind technological progress and sustainable development goals are not accomplished. In contrast, The Iron Giant scenario represents the successful implementation of the sustainable development goals where technological development is the force behind the accomplishment of these goals. The scenario called Slow Progress represents a future where gradual technological improvements are present, but sustainability is still not seen as concerning the issue. The Humanist scenario illustrates a future where slow technological development is happening yet sustainable development goals are successfully implemented. Finally, the scenarios are used to initiate discussions by illustrating what the future of research and education could look like and a list of strategies for future CPS research and education environments is proposed. To this end, we invite educators, researchers, institutions and governments to develop the necessary strategies to enable data-orientated, continuous, interdisciplinary, collaborative, ethical, and sustainable research and education by improving digital fluency, advancing digital equality, contributing to new ways of teaching complex thinking, expanding access to learning platforms and preparing next generations to adapt for a rapidly changing future of work conditions