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Today, food products are distributed all over the world. This has led to advantages in terms of availability but disadvantages in terms of more complex food supply chains. Global food competition is intense and therefore actors have started to adapt their mindsets toward a more holistic view and a supply chain perspective. In addition, food scares during recent years have turned focus towards food

We discuss our current work on building an IDE for Modelica, and how we intend to support renaming. Our current implementation of the compiler and the name completion support is done using reference attribute grammars, implemented in the JastAdd metacompilationsystem. For renaming we plan to follow the approach of inverse lookups, developed by Schfer, Ekman, and de Moor. Modelica has challenging n

How do individuals feel and think themselves on themselves? Our actual multicultural world offer us a unique, natural experiment for a detailed study of this problematic. We will use the Meaning Constitution Analysis methodology for planification of research as it is: 1. Oriented towards meaning, as it is constituted in/by the individual in his daily life activities; 2. Oriented towards a gatherin

A survey of the theory of propagation of transient transverse electromagnetic waves in temporally dispersive, bi-isotropic slabs is given, and a novel wave splitting, which completely separates right-going and left-going waves in the dispersive medium, is proposed. The new approach leads to a simple scattering relation in terms of wave propagators and single-interface scattering operators only. Th

We celebrate Certec’s 20th birthday . . . . . . by giving you a book of 20 important ideas filled with pictures and text. Each idea is expressed in a succinct heading that sums up what we have learned over the years. The ideas also act as a complement to all the reports, website cover pages, brochures, lectures and annual reports. There are 30,000 documents at www.certec.lth.se that provide the

A power-series expansion method for approximate analysis of the guided modes in a cylindrical, radially inhomogeneous dielectric waveguide is presented. The method is developed for a piece-wise polynominal permittivity profile. The solution of the scalar wave equation is constructed by a sequence of power-series expantions. Convergence is ensured and accuracy maintained by regulating the distance

In this paper, physical limitations on the directivity D and Q-factor Q are derived for antennas of arbitrary shape. The quotient D/Q is shown to be bounded from above by the antenna volume and certain shape coefficients in terms of the eigenvalues of the high-contrast polarizability dyadic. The theory is exemplified by numerical results for the half-wave antenna with astonishing agreement.