Managing Transboundary Crises: Identifying the Building Blocks of an Effective Response System

In recent years, crises have become increasingly transboundary in nature. This exploratory paper investigates whether and how the transboundary dimensions of crises such as pandemics, cyber attacks and prolonged critical infrastructure failure accentuate the challenges that public and private authorities confront in the face of urgent threats. We explore the transboundary dimensions of crises and disasters, discuss how an increase in ‘transboundedness’ affects traditional crisis management challenges and investigate what administrative mechanisms are needed to deal with these compounded challenges. Building on lessons learned from past crises and disasters, our goal is to stimulate a discussion among crisis management scholars about the political‐administrative capabilities required to deal with ‘transboundary’ crises.     

Non‐Linear Beam Tracing on a GPU

Beam tracing combines the flexibility of ray tracing and the speed of polygon rasterization. However, beam tracing so far only handles linear transformations; thus, it is only applicable to linear effects such as planar mirror reflections but not to non‐linear effects such as curved mirror reflection, refraction, caustics and shadows. In this paper, we introduce non‐linear beam tracing to render these non‐linear effects. Non‐linear beam tracing is highly challenging because commodity graphics hardware supports only linear vertex transformation and triangle rasterization. We overcome this difficulty by designing a non‐linear graphics pipeline and implementing it on top of a commodity GPU. This allows beams to be non‐linear where rays within the same beam do not have to be parallel or intersect at a single point. Using these non‐linear beams, real‐time GPU applications can render secondary rays via polygon streaming similar to how they render primary rays. A major strength of this methodology is that it naturally supports fully dynamic scenes without the need to pre‐store a scene database. Utilizing our approach, non‐linear ray tracing effects can be rendered in real‐time on a commodity GPU under a unified framework.     

Synectics: Reflections of a Little‐s Practitioner

Vincent Nolan provides a valuable update on the body of knowledge known as Synectics. The contribution deserves attention as an account of a fascinating body of knowledge of a method seeking deliberately to stimulate creativity, particularly in small, facilitated groups. He also indicates a lack of awareness of such practical work from academic establishments. In this response I offer another perspective, from a practitioner of creative problem‐solving techniques based in an academic environment.     

Hardware‐Based Non‐Photorealistic Rendering Using a Painting Robot

We describe a painting machine and associated algorithms. Our modified industrial robot works with visual feedback and applies acrylic paint from a repository to a canvas until the created painting resembles a given input image or scene. The color differences between canvas and input are used to direct the application of new strokes. We present two optimization‐based algorithms that place such strokes in relation to already existing ones. Using these methods we are able to create different painting styles, one that tries to match the input colors with almost transparent strokes and another one that creates dithering patterns of opaque strokes that approximate the input color. The machine produces paintings that mimic those created by human painters and allows us to study the painting process as well as the creation of artworks.     

Crises as Learning Triggers: Exploring a Conceptual Framework of Crisis‐Induced Learning

This article contributes to the debate on organizational learning from crisis by shedding light on the phenomenon of crises as learning triggers. To unveil theoretical patterns of how organizational crisis‐induced learning may appear and develop, I suggest a conceptual framework based on concept categories and answers to four fundamental questions: what lessons are learned (single‐ or double‐loop)?; what is the focus of the lessons (prevention or response)?; when are lessons learned (intra‐ or intercrisis)?; is learning blocked from implementation or carried out (distilled or implemented)? The framework's applicability is explored in a study of how a Swedish utility and the city of Stockholm responded to two large‐scale blackouts in Stockholm. The final sections suggest four propositions for further research.     

Vega: Non‐Linear FEM Deformable Object Simulator

This practice and experience paper describes a robust C++ implementation of several non‐linear solid three‐dimensional deformable object strategies commonly employed in computer graphics, named the Vega finite element method (FEM) simulation library. Deformable models supported include co‐rotational linear FEM elasticity, Saint–Venant Kirchhoff FEM model, mass–spring system and invertible FEM models: neo‐Hookean, Saint–Venant Kirchhoff and Mooney–Rivlin. We provide several timestepping schemes, including implicit Newmark and backward Euler integrators, and explicit central differences. The implementation of material models is separated from integration, which makes it possible to employ our code not only for simulation, but also for deformable object control and shape modelling. We extensively compare the different material models and timestepping schemes. We provide practical experience and insight gained while using our code in several computer animation and simulation research projects.     

Non‐metamerism of boundary colors in multi‐primary displays

Abstract— A control sequence gives the intensities of the primaries for a pixel of a display device. The display gamut, i.e., the set of all the colors that a display can produce, is a zonohedral subset of CIE XYZ space and contains both boundary and interior colors. Displays with four primaries or more exhibit metamerism, in which different control sequences produce colors that appear identical to an observer. This paper shows mathematically that, provided no three primaries are linearly dependent, metamerism can only occur for interior colors. When there are four or more primaries, metamers can always be found for interior colors. A color on the gamut boundary, by contrast, is only produced by a unique control sequence. The proof used for displays can be extended to object‐color solids, to show that optimal colors, which are on the boundary of an object‐color solid, have unique reflectance functions.     

Modelling of Non‐Periodic Aggregates Having a Pile Structure

This paper presents a procedure for modelling aggregates such as piles that consist of arbitrary components. The method generates an aggregate of components that need to be accumulated, and an aggregate shape represents the surface of the target aggregate. The number of components and their positions and orientations are controlled by five parameters. The components, the aggregate shape and the parameters are the inputs for the method which involves placement and refinement steps. In the placement step, the orientation and initial position of a component are determined by a non‐periodic placement such that each component overlaps its neighbours. In the refinement step, to construct a pile structure, the position of each component is adjusted by reducing the overlap.     

Finite‐time Stability on a Class of Non‐autonomous SICNNs with Multi‐proportional Delays

This paper is concerned with the problem of finite‐time stability for a class of non‐autonomous shunting inhibitory cellular neural networks with multi‐proportional delays. An explicit criterion for the finite‐time stability of the system has been proposed by employing the differential inequality techniques. Moreover, an illustrative example and its numerical simulations are given to demonstrate the effectiveness of the obtained result.     

Stabilization of Non‐Linear Fractional‐Order Uncertain Systems

In this paper, we present a stabilization method on the non‐linear fractional‐order uncertain systems. Firstly, a sufficient condition for the robust asymptotic stabilization of the non‐linear fractional‐order uncertain system is presented based on direct Lyapunov approach. Secondly, utilising the matrix's singular value decomposition (SVD) method, the systematic robust stabilization design algorithm is then proposed. Finally, two numerical examples are provided to illustrate the efficiency and advantage of the proposed algorithm.     

Managing schema evolution in a container‐based persistent system

Managing schema evolution is a problem every persistent system has to cope with to be useful in practice. Schema evolution consists basically of supporting class modification and dealing with data objects created and stored under the old class definitions. Several proposals have been made to handle this problem in systems that follow a full orthogonally persistent approach, but, until now, there has not been any proposal to support it in container‐based persistent systems. In this paper we describe a schema evolution management system designed for Barbados. Barbados is a complete programming environment which is based on an architecture of containers to provide persistent storage. Barbados does not provide full orthogonal persistence, but, as will be described in this paper, its architecture has several other advantages. Among them is the fact that this model is especially suitable for solving the schema evolution problem. Copyright © 2002 John Wiley & Sons, Ltd.     

Non‐intrusive object introspection in C++

We describe the design and implementation of system architecture to support object introspection in C++. In this system, information is collected by parsing class declarations, and is used to build a supporting environment for object introspection. Our approach is non‐intrusive because it requires no changes in the original class declarations and libraries; hence, binary compatibility between objects before and after the addition of introspective capability is ensured. This is critical if one wants to integrate third‐party class libraries, which are often supplied as black boxes and allow no modification, into highly dynamic applications. We present two applications: the first is automatic I/O support for C++ objects, and the other is interactive exercise of dynamically loaded C++ class libraries. Copyright © 2001 John Wiley & Sons, Ltd.     

Heat Walk: Robust Salient Segmentation of Non‐rigid Shapes

Segmenting three dimensional objects using properties of heat diffusion on meshes aim to produce salient results. The few existing algorithms based on heat diffusion do not use the full knowledge that can be gained from heat diffusion and are sensitive to varying kinds of perturbations. Our simple algorithm, Heat Walk, converts the implicit information in the heat kernel to explicit knowledge about the pathways for maximum heat flow capacity. We develop a two stage strategy for segmentation. In the first stage we quickly identify regions which are dominated by heat accumulators by employing a greedy algorithm. The second stage partitions out dissipative regions from the previously discovered accumulative regions by using a KL‐divergence based criterion. The resulting algorithm is both independent of human intervention and fast because of the globally aware directed walk along the maximal heat flow capacity. Extensive experimental evidence shows the method is robust to a variety of noise factors including topological short circuits, surface holes, pose variations, variations in tessellation, missing features, scaling, as well as normal and shot noise. Comparison with the Princeton Segmentation Benchmark (PSB) shows that our method is comparable with state of the art segmentation methods and has additional advantages of being robust and self contained. Based upon theoretical insight the convergence and stability of the Heat Walk is shown.     

Non‐smooth structured control design with application to PID loop‐shaping of a process

Feedback controllers with specific structure arise frequently in applications because they are easily apprehended by design engineers and facilitate on‐board implementations and re‐tuning. This work is dedicated to H_∞ synthesis with structured controllers. In this context, straightforward application of traditional synthesis techniques fails, which explains why only a few ad hoc methods have been developed over the years. In response, we propose a more systematic way to design H_∞ optimal controllers with fixed structure using local optimization techniques. Our approach addresses in principle all those controller structures which can be built into mathematical programming constraints. We apply non‐smooth optimization techniques to compute locally optimal solutions, and provide practical tests for descent and optimality. In the experimental part we apply our technique to H_∞ loop‐shaping proportional integral derivative (PID) controllers for MIMO systems and demonstrate its use for PID control of a chemical process. Copyright © 2007 John Wiley & Sons, Ltd.     

Managing the Innovation of a Corporate IT‐based Cable Design System

Managing new Information Technology innovations requires an understanding of factors that influence organisational choice. When large firms invest in new IT applications such as Computer Aided Design, there is reason to doubt that they adequately understand user needs. Empirical investigation in a UK cables producing Multinational Company highlights the practical challenges faced by such designers, when designing bespoke systems technologies. In addition to understanding end market requirements, it is imperative to understand existing organisational practices and constraints. Evidence from this in‐depth innovation study points to the need to develop integrative theoretical accounts, which include insights from the innovation adoption process as well as the innovation design process.     

Non‐diagonal controllers in MIMO quantitative feedback design

This paper discusses multivariable quantitative feedback design through the use of controllers with off‐diagonal elements. Controller design for multivariable plants with significant uncertainty is simpler and potentially less conservative if some sort of dominance is achieved (by reducing the interaction effect of off‐diagonal plant elements) before a diagonal (decentralized) controller design is attempted. Traditional approaches for achieving dominance are not applicable when plant uncertainty must be considered. This paper discusses parallel and series implementations and for the latter, a pseudo‐Gauss elimination approach to the design has been developed. The interaction is measured using the Perron–Frobenius root of an interaction matrix. In some applications, it is possible to trade off individual plant cases against each other in order to reduce to the worst‐case interaction over the entire plant set. Copyright © 2002 John Wiley & Sons, Ltd.     

Non‐linear design of active frequency doublers

A procedure has been developed for the design of microwave active frequency doublers. A fully nonlinear model and design‐oriented algorithm are used for the best accuracy. Optimum conversion gain and stable operations are achieved as a result of optimum harmonic loading. A simplified analysis is also presented, giving results in qualitative and good quantitative agreement with the exact nonlinear results. Such a procedure represents a first‐pass procedure for device selection and performance evaluation. The same technique can be extended to higher‐order frequency multipliers. ©1999 John Wiley & Sons, Inc. Int J RF and Microwave CAE 9: 117–128, 1999.     

Non‐parametric linear time‐invariant extensions of non‐invertible and backlash plant

A rigorous validation for the use of a set of linear time‐invariant models as a surrogate in the design of controllers for uncertain nonlinear systems, which are invertible as one‐to‐one operators, such as used in the nonlinear quantitative feedback theory (NLQFT) design methodology has been given by Baños and Bailey. This paper presents a similar validation but weakens the requirement on the invertibility of the nonlinear plant by application of Kakutani's fixed‐point theorem and an incremental gain constraint on the plant within its operational envelope. The set of linear time‐invariant models to be used for design is shown to be an extension (termed here the linear time‐invariant extension—LTIE) of the nonlinear plant restricted to the desired output operating space. A new non‐parametric approach to the modelling of the LTIE is proposed which is based on Fourier transforms of the plant I/O data and which accordingly may be based solely on experimental testing without the need for an explicit parametric plant model. This new approach thus extends the application of robust linear controller design methods (including those of NLQFT) to nonlinear plants with set‐valued (multi‐valued) inverses such as those containing backlash and also to plants for which explicit parametric models are difficult to obtain. The method is illustrated by application of the non‐parametric approach to an NLQFT tracking controller design for a mechanical backlashed servomechanism problem. Copyright © 2013 John Wiley & Sons, Ltd.     

Managing the Knowledge‐Creating Context: A Strategic Time Approach

Understanding the contexts of knowledge is necessary to manage knowledge processes successfully. The goal of this paper is to provide a theoretical framework for understanding and utilizing knowledge that is embedded in contexts, focusing on the relationship between time and knowledge processes. This paper integrates the time lens and the literature on the knowledge based view to develop four different time contexts that can enable different organizational knowledge processes. Propositions on how to utilize time to create enabling contexts for organizational knowledge creation and innovation are developed. Suggested intervention strategies help to create contexts for knowledge creation and exploitation.