A scalable line-independent design algorithm for voltage and frequency control in AC islanded microgrids

We propose a decentralized control synthesis procedure for stabilizing voltage and frequency in AC Islanded microGrids (ImGs) composed of Distributed Generation Units (DGUs) and loads interconnected through power lines. The presented approach enables Plug-and-Play (PnP) operations, meaning that DGUs can be added or removed without compromising the overall ImG stability. The main feature of our approach is that the proposed design algorithm is line-independent. This implies that (i) the synthesis of each local controller requires only the parameters of the corresponding DGU and not the model of power lines connecting neighboring DGUs, and (ii) whenever a new DGU is plugged in, DGUs physically coupled with it do not have to retune their regulators because of the new power line connected to them. Moreover, we formally prove that stabilizing local controllers can be always computed, independently of the electrical parameters. Theoretical results are validated by simulating in PSCAD the behavior of a 10-DGUs ImG

Design-Led Sustainable Transition in Organization: A framework to guide and evaluate employee change

Design for Sustainability Transition (DfST) is gaining popularity in both academia and practice, seeking to guide socio-technical systems toward more sustainable futures through design but remaining a high-level approach that is difficult to evaluate. The authors also disagree on the designer’s role during the transitions, leaving it open to exploration. Organisations considered a socio-technical system play a crucial role in solving the climate crisis we are experiencing and need to be guided through change. Working on employees and their practices makes it possible to initiate a snowball effect capable of triggering the necessary cultural change. The Design-Led Innovation approach can be a valuable guide in the cultural transformation of companies, connecting strategic aspects with more pragmatic ones, such as products or services solutions. This also suggests the figure of the Design Innovation Catalyst as a change agent to facilitate the introduction of design as a driver of change. This paper proposes a Conceptual Framework based on Design-Led Innovation and Social Practice Theory to guide the sustainable transition and evaluate the change brought to individuals' practices. Through a 12-month collaboration with an Italian secondary packaging company, it was possible to test the framework and its impact on design-as-practice. The results consolidate the validity of Design-Led Innovation for Sustainable Transition, showing its potential and limitations. The role played by the Design Innovation Catalyst proves to be crucial in facilitating transition and leading to changes in practices

Self-deformable modular robot inspired by cellular structure

Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2008.Includes bibliographical references (leaves 15-16).In this paper, we present a modular robot design inspired by the creation of complex structures and functions in biology via deformation. Our design is based on the Tensegrity model of cellular structure, where active filaments within the cell contract and expand to control individual cell shape, and sheets of such cells undergo large-scale shape change through the cooperative action of connected cells. Such deformations play a role in many processes: early embryo shape change, heart and intestine function, and in lamprey locomotion. Modular robotic systems that replicate the basic deformable multicellular structure have the potential to quickly generate large-scale shape change and create time-varying shapes to achieve different global functions. We present a design and initial hardware implementation of this model. Our design includes four different modular components: (1) actuating links, (2) passive (compressive) links, (3) elastic surface membranes, and (4) universal connecting interfaces. In both hardware implementation and simulation, we show several self-deformable structures that can be generated from these four components, including the deformable surface, expandable cube, terrain-adaptive bridge from [1] and some examples inspired by biology. We argue that self-deformation is more appropriate for dynamic and sensing-adaptive shape change in a certain class of tasks.by Kristina M. Haller.S.B

Alternative Workspaces: Changing Where + How People Work

The modern workspace is constantly evolving; what is in store for the future of how and where we work? Workspace creators need to provide a variety of activity landscapes intended for specific activities, and accessible to all. One size, one design, does not fit all! This thesis explores possibilities of connecting generations by transforming the traditional workspace to accommodate the ever-blurring boundaries between the workspace, hospitality spaces and the home spaces with the infusion of sophisticated modularity. Four generations contribute to today’s work environment including Baby Boomers, Generation X, Generation Y and Post Millennials. All of these generations have different expectations, values and motivations about their work environments. How can we become attuned to this emerging generation of workspace users, who often have very different ideas about how work should get done? Moreover, this thesis analyzes the integration and emphasis of work/life balance, workspace flexibility and user wellbeing, reinforced ideas generated through an open design processes, and explores how co-creation can facilitate the diffusion of innovation within an organization’s common workspaces known as lounge space. This thesis builds upon an existing product portfolio of office furniture by implementing human centered design through co-creation, and finding inspiration for innovation through heuristic methodologies in order to inform design decisions. With an emphasis on workspace ideologies and theories, exciting propositions based on design principles and workspace psychology, such as the incorporation of sophisticated modularity, lounge-as-office principles, prioritizing play, and supporting working happy, provide interesting insights into this research. This collection of artifacts provides functional and flexible characteristics while being attractive enough to be enjoyed outside of workspaces.Submitted in partial fulfillment of the requirements for the degree of Master of DesignWellbeingCreative workspacesWorkspace cultureWork/life balanceModular furnitureUser choiceOpen desig

Childifying

In the last decades, socio-spatial fragmentation has become a growing problem in the urban environment. This thesis aims to offer knowledge on how a child-centered spatial approach, termed Childifying, can help overcome socio-spatial fragmentation. Childifying is formulated by making a strategy and site-specific design for urban open space transformation in the neighborhood of Southern Friedrichstadt in Berlin. The term Childifying means to make the urban environment more child friendly and less fragmented. Methods used for building knowledge and developing the approach were literature study and site reading. The landscape research method traveling transect was the methodological framework for the site reading and included on site interviews, on site exploration and literature and archive studies. Planning and policy scenarios promoting safer mobility, play, exercise and outdoor education are recommended. The site-specific design scenarios propose connecting the neighborhood schools to inside and outside areas of opportunities that can be temporary classrooms for the children. There, children from different schools meet and get to know each other, making the schools and the community more connected. Scenarios also propose safer routes for children by making car-free and shared streets, implementing a children's boulevard and a web of play and exercise stations. Different types of child-centered events for the neighborhood are also proposed. To Childify Southern Friedrichstadt is a transferable planning and design approach that can be adapted to other urban sites dealing with socio-spatial fragmentation. *childifying means making urban environment more child friendly in the same way as densifying means more dense. And through that less socio-spatial fragmented

A Computational Model of Creative Design as a Sociocultural Process Involving the Evolution of Language

The aim of this research is to investigate the mechanisms of creative design within the context of an evolving language through computational modelling. Computational Creativity is a subfield of Artificial Intelligence that focuses on modelling creative behaviours. Typically, research in Computational Creativity has treated language as a medium, e.g., poetry, rather than an active component of the creative process. Previous research studying the role of language in creative design has relied on interviewing human participants, limiting opportunities for computational modelling. This thesis explores the potential for language to play an active role in computational creativity by connecting computational models of the evolution of artificial languages and creative design processes. Multi-agent simulations based on the Domain-Individual-Field-Interaction framework are employed to evolve artificial languages with features that may support creative designing including ambiguity, incongruity, exaggeration and elaboration. The simulation process consists of three steps: (1) constructing representations associating topics, meanings and utterances; (2) structured communication of utterances and meanings through the playing of “language games”; and (3) evaluation of design briefs and works. The use of individual agents with different evaluation criteria, preferences and roles enriches the scope and diversity of the simulations. The results of the experiments conducted with artificial creative language systems demonstrate the expansion of design spaces by generating compositional utterances representing novel concepts among design agents using language features and weighted context free grammars. They can be used to computationally explore the roles of language in creative design, and possibly point to computational applications. Understanding the evolution of artificial languages may provide insights into human languages, especially those features that support creativity

Exploring the interactions underlying flow states: A connecting analysis of flow occurrence in European Tour golfers

Objectives: Research to date has identified a range of factors suggested to facilitate flow states in sport. However, less attention has focused on how exactly those facilitating factors influence the occurrence of flow. Therefore, this study aimed to explore the specific ways in which such facilitators influenced flow occurrence in European Tour golfers. Design: Qualitative design. Method: Ten full-time golfers from the European Tour (M age=37; SD=13.08) participated in semi-structured interviews investigating the occurrence of their flow states. Data were interpreted using an iterative process of thematic and connecting analyses. Results: Ten facilitators of flow were identified, of which commitment and the caddie have not been reported previously. Twenty four connecting links were identified in the data, through which the caddie, effective preparation, and high-quality performance appeared to be most influential for flow occurrence. Confidence and concentration also emerged as key constructs underlying the flow experience in this setting. Conclusion: A central contribution of this study is the identification of ways in which facilitating factors could influence flow occurrence in elite golf. This process adds detail to understanding of flow occurrence, and moves beyond simply identifying factors which are associated with the experience. As such, connecting analysis is proposed as an additional strategy for qualitatively investigating flow occurrence in sport. Results are discussed in relation to previous literature, and recommendations are identified for researchers, athletes, coaches and practitioners

Plug-and-play and coordinated control for bus-connected AC islanded microgrids

This paper presents a distributed control architecture for voltage and frequency stabilization in AC islanded microgrids. In the primary control layer, each generation unit is equipped with a local controller acting on the corresponding voltage-source converter. Following the plug-and-play design approach previously proposed by some of the authors, whenever the addition/removal of a distributed generation unit is required, feasibility of the operation is automatically checked by designing local controllers through convex optimization. The update of the voltage-control layer, when units plug -in/-out, is therefore automatized and stability of the microgrid is always preserved. Moreover, local control design is based only on the knowledge of parameters of power lines and it does not require to store a global microgrid model. In this work, we focus on bus-connected microgrid topologies and enhance the primary plug-and-play layer with local virtual impedance loops and secondary coordinated controllers ensuring bus voltage tracking and reactive power sharing. In particular, the secondary control architecture is distributed, hence mirroring the modularity of the primary control layer. We validate primary and secondary controllers by performing experiments with balanced, unbalanced and nonlinear loads, on a setup composed of three bus-connected distributed generation units. Most importantly, the stability of the microgrid after the addition/removal of distributed generation units is assessed. Overall, the experimental results show the feasibility of the proposed modular control design framework, where generation units can be added/removed on the fly, thus enabling the deployment of virtual power plants that can be resized over time

Supporting Worth Mapping with Sentence Completion

Expectations for design and evaluation approaches are set by the development practices within which they are used. Worth Centred Development (WCD) seeks to both shape and fit such practices. We report a study that combined two WCD approaches. Sentence completion gathered credible quantitative data on user values, which were used to identify relevant values and aversions of two player groups for an online gambling site. These values provided human value elements for a complementary WCD approach of worth mapping. Initial worth maps were extended in three workshops, which focused on outcomes and user experiences that could be better addressed in the current product and associated marketing materials. We describe how worth maps were prepared for, and presented in, workshops, and how product owners and associated business roles evaluated the combination of WCD approaches. Based on our experiences, we offer practical advice on this combinination

Toward an Ecology of Gaming

In her introduction to the Ecology of Games, Salen argues for the need for an increasingly complex and informed awareness of the meaning, significance, and practicalities of games in young people's lives. The language of the media is replete with references to the devil (and heavy metal) when it comes to the ill-found virtues of videogames, while a growing movement in K-12 education casts them as a Holy Grail in the uphill battle to keep kids learning. Her essay explores the different ways the volume's contributors add shades of grey to this often black-and-white mix, pointing toward a more sophisticated understanding of the myriad ways in which gaming could and should matter to those considering the future of learning