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Attention and tool-use in the evolution of language

It is argued that the capacity to focus attention is crucial for intentional communication. Intentional communication is goal-intended; directed at changing mental states and as a consequence behaviour; about a referential object common to sender and recipient; and about objects that may be context-and referent-independent. Three different kinds of attention is discerned: scanning, attention attra

Generalisation Methods for Propagating Updates between Cartographic Data Sets

Automation is increasingly important in producing and maintaining cartographic data sets. This thesis deals with automatic methods to propagate updates between cartographic data sets. The major idea is to update only the most detailed data set (master data set) and then propagate these updates automatically to less detailed data sets (target data sets). The approach used is firstly to formulate li

A 0.7 - 3.7 GHz Six Phase Receiver Front-End With Third Order Harmonic Rejection

This paper presents a highly linear receiver frontend operating from 700 MHz to 3.7 GHz with 3rd order harmonic rejection. It consists of a complementary low noise transconductance amplifier with capacitive cross coupling and negative gm current sources, a six phase current-mode passive mixer, and baseband transimpedance amplifiers providing programmable gain. The circuit has been fabricated in 65

Structural Models of Network Contacts Between Actors Governed by Activity and Attraction

This thesis consists of five papers on the subject of statistical modeling of stochastic networks. The NG-model proposed in Paper I combines a block structure with parameters that capture the identities of vertices and thus the new approach stresses the concept of ego-nets, which describes the structure around identified vertices. The models proposed in Papers II-V are closely related to the NG-mo

Lake Urmia is disappearing

The present article is a translation—to Farsi—of an article by Dr. Ali Mirchi (postdoctoral research associate at the Department of Civil and Environmental Engineering, Michigan Technological University), Dr. Kaveh Madani (lecturer in Environmental Management at the Centre for Environmental Policy, Imperial College London) and Dr. Amir Aghakouchak (assistant professor at the Department of Civil an

High-frequency switching and Kerr effect - nonlinear problems solved with nonstationary time domain techniques

A time domain method building on the concept of wave splitting is used to study direct wave propagation phenomena in weakly nonlinear media. The starting point is the linear wave equation with time-dependent coefficients. This means that the studied nonlinear medium in some sense has to be approximated with a nonstationary medium which changes while the wave passes through. For the nonstationary e

Sum Rules for Parallel Plate Waveguides: Experimental Results and Theory

An experimental approach to verify the forward scattering sum rule for periodic structures is presented. This approach allows an upper bound on the total cross section integrated over a bandwidth from a simple static problem to be found. Based on energy conservation, the optical theorem is used to construct a relation between the total cross section and the forward scattering of periodic structure