4,409 research outputs found
Four decades of mathematical system theory
Get PDFAs a follow-up to the volume Three Decades of Mathematical System Theory that the authors of this paper edited in 1989 at the occasion of the fiftieth birthday of Jan Willems, we discuss some trends that have become more visible in the past decade. It is argued that system theory is ready to play a role in many different fields of science. Three examples of nontraditional application areas are discussed
Modelling of switching dynamics in electrical systems
No full textIn this paper, we use the switched linear differential systems framework [8] to model electrical devices with switching dynamics. Modularity, i.e. independent modelling and incremental combination of complex dynamics, is an important feature of this approach, since we can incorporate new dynamic modes to the bank without altering the existing ones. This makes our approach ideal for describing complex systems (e.g. energy distribution networks). Our modelling approach differs fundamentally from the traditional representation-based theory where the use of a global state space is required
J.C. Steyn Collection index
No full textThis index describes the J. C. Steyn collection which includes background material for 3 biographies by J.C. (Jaap) Steyn namely N.P. van Wyk Louw, P.J. Cillié and MER (M.E. Rothman). Prof. J.C. Steyn (1939-) is an educationist, linguist and author. Correspondence ; clippings ; photographs ; book reviews ; articles ; speeches ; varia compiled in 23 pamphlet boxes
Product Innovation Knowledge Transfer for Developing Countries: Towards a systematic Transfer Approach
No full textThe transfer of knowledge on product innovation to small- and medium-sized enterprises and local knowledge institutions in developing countries is expected to be one of the key drivers for competiveness and economical growth, and a part of the solution to environmental and social challenge. In that respect, this PhD study focuses on how the process of the current knowledge transfer takes place and how it can be improved. A combination of literature review and empirical research has resulted into a conceptual framework to describe the complex and dynamic process of product innovation knowledge transfer to developing countries. In order to improve this process, a systematic approach has been developed and operationalized by a needs assessment tool and a design manual: The UNEP Design for Sustainability for Developing Economies (D4S-DE) Manual (www.d4s-de.org). Both tools have been tested in practice by practitioners and have been evaluated by an academic review board.Design EngineeringIndustrial Design Engineerin
Where do we draw lines: professional relationship boundaries and the child and youth care practitioner
No full textThe question of professional relationship boundaries is a poignant one, in light of the many boundary grey-zones that are created by the variety of young people’s needs, practice settings and professional relationship contexts within the field of child and youth care. In order to support practitioners’ development of critical thought and awareness of professional boundaries, this paper applies a professional relationship boundaries conceptual framework to child and youth care work, and the literature is consulted to explore the impacts of boundary violations, influences on individual’s boundaries, cues to indicate blurring boundaries, and key strategies to maintain balanced boundaries
Anthropometry of the Beaver, Sekani, and Carrier Indians:
Get PDFby J.C. Boileau GrantBulletin (National Museum of Canada) ; 81. Bulletin (National Museum of Canada). Anthropological series. ; 18
J.C. Painter letter to Benjamin Lundy
No full textLetter from J.E. Painter to (presumably) Benjamin Lundy, answering a request for information about the history and operations of the Underground Railroad. Letter includes details of a story of an ex-slave transported on the Underground Railroad through Ohio and stories of the plight of other fugitive slaves crossing the Ohio River.
Benjamin Lundy (1789-1839) was a prominent Quaker abolitionist best known for his development of abolitionist periodicals. His "Genius of Universal Emancipation" was first published in 1821 from his home in Mt. Pleasant, Ohio, and enjoyed a wide circulation across the antebellum United States. In the 1820s, the young William Lloyd Garrison came to work for The Genius. Benjamin Lundy traveled widely seeking subscriptions to The Genius, giving talks about the anti-slavery movement, and observing and documenting the conditions of enslaved people across the Americas. He was also involved in the establishment of freed slave colonies in Mexico
Turbulent wakes of plates with non-equilibrium similarity scalings
No full textWe have conducted hot wire anemometry measurements of six different axisymmetric turbulent wakes which demonstrate the existence in all these wakes of non-equilibrium mean flow profile scalings and of the underlying self-preservation and non-equilibrium dissipation scalings. These mean flow profile scalings are different from those of all documented canonical boundary-free turbulent shear flows to date, all of which have been established for very far downstream regions
- …
