This survey characterizes an emerging research area, sometimes called coordination theory, that focuses on the interdisciplinary study of coordination. Research in this area uses and extends ideas about coordination from disciplines such as computer science, organization theory, operations research, economics, linguistics, and psychology. A key insight of the framework presented here is that coordination can be seen as the process of managing dependencies among activities. Further progress, therefore, should be possible by characterizing different kinds of dependencies and identifying the coordination processes that can be used to manage them. A variety of processes are analyzed from this perspective, and commonalities across disciplines are identified. Processes analyzed include those for managing shared resources, producer/consumer relationships, simultaneity constraints, and tank/subtask dependencies. Section 3 summarizes ways of applying a coordination perspective in three different domains: (1) understanding the effects of information technology on human organizations and markets, (2) designing cooperative work tools, and (3) designing distributed and parallel computer systems. In the final section, elements of a research

We present a new class of statistical models designed for life history analysis of plants and animals. They allow joint analysis of data on survival and reproduction over multiple years, allow for variables having different statistical distributions, and correctly account for the dependence of variables on earlier variables (for example, that a dead individual stays dead and cannot reproduce). We illustrate their utility with an analysis of data taken from an experimental study of Echinacea angustifolia sampled from remnant prarie populations in western Minnesota. Statistically, they are graphical models with some resemblance to generalized linear models and survival analysis. They have directed acyclic graphs with nodes having no more than one parent. The conditional distribution of each node given the parent is a oneparameter exponential family with the parent variable the sample size. The model may be heterogeneous, each node having a different exponential family. We show that the joint distribution is a flat exponential family and derive its canonical parameters, Fisher information, and other properties. These models are implemented in an R package ‘aster ’ available from CRAN.

This paper presents industry test cases that illustrate the multi-disciplinary, constructive, iterative, and unique character of AEC projects. These test cases show that, to perform their tasks on these projects, AEC engineers construct task-specific engineering views from information in other engineering views. These engineers have difficulty constructing and integrating task-specific views on these projects today. Based on these observations, this paper proposes that engineers could benefit from an approach that provides them with simple, formal methods to iteratively construct a task-specific view from other views as needed, and control the integration of these views as the project progresses. In this way, an integrated project model emerges as a directed acyclic graph of task-specific views and dependencies. This paper defines requirements for such an approach, and discusses current project modeling approaches in terms of these requirements. While points of departure, existing approaches do not explicitly enable engineers to easily construct and integrate task-specific views and control a project model in a way that maps closely to the way AEC projects work today. To address these requirements, this paper introduces the conceptually simple Perspective Approach that enables engineers from multiple disciplines to formalize the dependency of a view

This paper introduces a novel application of the SOM method, in which the neuron grid is not trained by high-dimensional feature space vectors, but by geographic coordinates expressed in latitude and longitude. Specifically, the training data set consists of 14,489 positions sampled in an equal-area manner from the earth’s landmasses. Contrary to traditional SOM applications, in which the neural network consists of several dozen to several thousand neurons, training occurs on a very high-resolution SOM of 125,000 neurons. In effect, SOM training defines a non-linear map projection, in contrast to the projection formulas used in traditional map projections. Following training, the SOM is applied to a data set of 100,000+ vertices defining polygon geometry for coastlines and country boundaries. Finally, a two-dimensional visualization of countries is derived from SOM-based vertex locations.

1 Introduction One of the most interesting and recent applications of computer science is that to sys-tems biology. The great challenge is to understand whether models, originally developed for describing systems of interacting components, can be applied for modeling and analyzing bi-ological systems. This could offer biologists very useful simulation and verification tools that could replace expensive experiments in vitro or guide the experiments by making predictionson their possible results. Among the many formalisms that have been successfully applied to biology there aretraditional specification languages for concurrent and reactive systems [25,20,19], and process calculi, designed for modeling distributed and mobile systems. Process calculi turnedout to be very appropriate for describing both the molecular and biochemical aspect, as pioneered by the application of stochastic ss-calculus [36,34]. New process calculi have also beenproposed in order to faithfully model biological structures such as compartments and membranes, which play a key role in the organization of biomolecular systems. Recent proposalsare BioAmbients [35], Beta-Binders [33], and Brane calculi [2].

It is demonstrated that the stationary Veselov-Novikov (VN) and the stationary modified Veselov-Novikov (mVN) equations describe one and the same class of surfaces in projective differential geometry: the so-called isothermally asymptotic surfaces, examples of which include arbitrary quadrics and cubics, quartics of Kummer, projective transforms of affine spheres and rotation surfaces. The stationary mVN equation arises in the Wilczynski approach and plays the role of the projective "Gauss-Codazzi" equations, while the stationary VN equation follows from the Lelieuvre representation of surfaces in 3-space. This implies an explicit Backlund transformation between the stationary VN and mVN equations which is an analog of the Miura transformation between their (1+1)-dimensional limits. Present address: Fachbereich Mathematik, SFB 288, Technische Universitat Berlin, 10623 Berlin, Deutschland, e-mail: fer@sfb288.math.tu-berlin.de 1 Introduction The Veselov-Novikov (VN) equation u t = ...

Most of the watermarking schemes that have been proposed until now employ a correlator in the detection stage. The current paper proposes a new detector scheme that can be applied in the case of additive watermarking in the DCT or DWT domain. Certain properties of the probability density function of the coefficients in these domains are exploited in order to construct an asymptotically optimal detector based on well known results of the detection theory. Detection is performed without the use of the original image, as in methods employing different detectors. Experimental results prove the superiority of the proposed detector over the correlator.

Previous research has indicated that the H* of a nuclear accent may be realised as a flat stretch of contour rather than as a single turning point. The duration of this plateau and its alignment within the accented syllable and foot are affected by the segmental and prosodic structure of the utterance. The present work investigates whether a non-structural variable, namely pitch span, also affects the realisation of the plateau. Speakers imitate all-sonorant utterances in different pitch spans. Both the duration and alignment of the plateau vary with pitch span but in ways different from their variation with prosodic structure. Results also indicate that the beginning and end of the falling movement within the contour are anchored within the syllable and foot for each speaker.

It is possible to characterize the different stages of history according the type of technology available. The last fifty years of human history have been referred to as “The Information Age " because of the great advancements and innovations of technology in electronics, computers and communications. The first part of this work presents a method based on the generation and exploitation of a database for the measurement of information technology gradients. The lack of the innovative data in earlier historic times is compensated by the consideration of the transport technologies as IT. The obtained result is a clear exponential growth curve. If the IT is driver of the global change, the notorious changes in the resulting graph can be related to the appearance of the Kondrattief cycles or "K " waves. Modelski [48] pointed out that the evolution of economic processes is closely related to the rate of growth in technological learning. According to the obtained results, the expected rate of change for IT innovation during the first two decades of the XXI Century will surely surpass the rate of change of technological learning. This will probably generate a non-sustainable system unless a change in the human consciousness occurs. Apparently, the sustainable evolution of the world system will depend on the appropriate technological selections, provoking the adjustment of innovation gradients to the rates of technological learning within the next generational cycles. RESUMEN

Modelling the incidence of self-employment has traditionally proved problematic. Whilst the individual supply side characteristics of the self-employed are well documented, the literature has largely neglected (or misspecified) demand side aspects. In this paper we present results from an econometric framework that allows us to separately, and simultaneously, model the supply and demand side characteristics that determine employment outcomes. We show that whilst individual characteristics are important determinants of the type of employment contract that individuals hold, there are also important contract specific factors that influence the nature of the contract an individual is employed under. Our results suggest that workers may be “captive ” to a particular type of employment because of the sector in which they work, the number of hours they prefer to work and their ethnicity. The results are based on a new estimator, the parameterised DOGEV model, which allows for ordering and correlation in the observed alternatives, and for captivity within an observed alternative. Keywords: Self-employment, captivity