C. W. I. Pistorius

Two-dimensional superresolution radar imaging using the MUSIC algorithm

The multiple signal classification (MUSIC) algorithm developed by Schmidt [1986] is applied for two-dimensional radar imaging. The performance of the MUSIC algorithm using spatial smoothing for decorrelation is demonstrated. Two-dimensional radar images are generated for a simulated target as well as a target measured in the compact range at the University of Pretoria, South Africa. >

On the Future of Technological Forecasting

Technological forecasting is now poised to respond to the emerging needs of private and public sector organizations in the highly competitive global environment. The history of the subject and its variant forms, including impact assessment, national foresight studies, roadmapping, and competitive technological intelligence, shows how it has responded to changing institutional motivations. Renewed focus on innovation, attention to science-based opportunities, and broad social and political factors will bring renewed attention to technological forecasting in industry, government, and academia. Promising new tools are anticipated, borrowing variously from fields such as political science, computer science, scientometrics, innovation management, and complexity science.

Multi-mode interaction among technologies

Abstract Technological innovation is manifested in the development of new products, processes and techniques such that emerging technologies often substitute for more mature technologies. The interaction between technologies is typically referred to as competition , implying a confrontational interaction. The setting of technology strategy is thus often concerned with issues relating to the competition between emerging technologies and the response of mature technologies to the offense from emerging technologies-strategies for attack and defense. In this paper it is argued that the interaction between technologies should be viewed in a broader sense than mere competition, and it is suggested that a multi-mode framework provides a much richer setting for assessing the interaction of two or more technologies. This concept has been successfully applied in biological and organizational ecology, and it is shown that it can be equally useful when applied to the dynamics of technological interaction. It is proposed that the effect that one technology has on anothers growth rate be taken as a classification criterion. Examples are given to illustrate that three major modes of interaction exist, namely pure competition, symbiosis and predator-prey. In addition, the notion that the interaction between technologies can in general shift temporally from one mode to another is motivated. It is suggested that, since the characteristics of the three modes differ from one another, it is appropriate to develop managerial strategies that apply specifically to each of the three modes, instead of just applying generic ‘competition’ strategies.

Analyzing technological threats and opportunities in wireless data services

Abstract The ability to assess the threat and opportunity that technological innovations pose to an organisations profitability, growth and survival has become one of the key elements in the development of offensive and defensive innovation strategies. Central to this process of assessing technological threats and opportunities is the need to analyze various aspects of identified technological developments. A range of analysis techniques exists, and a number of these are discussed and simultaneously applied to a specific technological development. While threat and opportunity assessment is relevant to almost any company in any industry, it is especially relevant to industries characterised by high rates of volatility such as the communications industry. The technological development, which has been chosen to apply these analysis techniques to, is the offering of 2.5/3G wireless data services, which is currently of great significance in the communications industry. The point of view that is taken is that of a European mobile network operator (MNO) that needs to assess the threats and opportunities that this development poses to its business. The result shows that the analysis process leads to a better understanding of not only the identified developments, their driving forces and enablers, but also their possible impacts on the organisation. This greatly enables the extent to which developments represent a threat or opportunity for a specific organisation to be assessed. In the framework of the overall technological threat and opportunity assessment methodology, the results of the analysis process will feed into the strategy formulation process where possible organisational responses can be developed.

Technological Threat and Opportunity Assessment

Abstract One of the major challenges in the management of innovation is a practical and useful implementation of technology forecasting. This article proposes the concept of aniticpating the technological future, and that a structured approach to this concept could be an invaluable aid to technical decision-making. The notion of technological threat and opportunity assessment is presented as a useful framework for anticipating technological change. This notion is based on a dual approach. Firstly, a rapidly changing global technological landscape necessitates keeping track of technological developments. However, since we are dealing with innovation (rather than mere invention), the market implications are as important as the technological ones and have to be accounted for as such. Secondly, any organisation could be considered to be technology-based to some or other degree, implying that technologies have the ability to affect the bottom line of the organisation in some way. It is thus required to assess the business impact of such technologies, typically through a technology or innovation audit. Having assessed specific technological threats and opportunities facing the organisation, an innovation strategy needs to be developed in response to the identified threats and opportunities. Various possible offensive and/or defensive responses should be considered, culminating in the selection and implementation of an optimal strategy.

Implications of the Dominant Design in Electronic Initiation Systems in the South African Mining Industry

Abstract This article analyzes an emerging technological innovation, namely, electronic initiation systems for mining explosives in South Africa. The concept of electronic initiation is presenting itself as a challenge to traditional initiation systems, particularly cap-and-fuse and shock tube technologies. From a technology strategy viewpoint, the challenge is to determine the nature of the managerial decisions that have to be addressed. The Utterback-Abernathy innovation model is used to assess the evolution of the emerging technology; it is found that the technology is still in the fluid phase and that a dominant design has not yet emerged. Since the dominant design is a very important milestone in the evolvement of the product with regard to both the technical and the business aspects, the immediate managerial focus should be on the evaluation factors that may influence the emergence of the dominant design. The emergence of a dominant design is, however, a complex process that depends on the interplay between a myriad of issues, including technological, market, social, economic, and related aspects. The paper anticipates the technological future of the innovation by exploring the factors that may influence the dominant design of electronic initiation systems, and casts the findings in a format that is useful for managerial decision support.

An efficient method to compute spurious end point contributions in PO solutions

A method is given to compute the spurious end point contributions in the physical optics (PO) solution for electromagnetic scattering from conducting bodies. The method is applicable to general three-dimensional structures. The only information required to use the method is the radius of curvature of the body at the shadow boundary. Thus, the method is very efficient for numerical computations. As an illustration, the method is applied to several bodies of revolution to compute the end point contributions for backscattering in the case of axial incidence. It is shown that in high frequency situations, the end point contributions obtained using the method are equal to the true end point contributions.

A dual chamber Gregorian subreflector system for compact range applications

A dual-chamber compact range configuration is proposed wherein the main reflector and target zone are located in the main chamber and an oversized Gregorian subreflector and associated feed assemblies in the other. The chambers are isolated by an absorber fence except for a small coupling aperture which is used to transmit signals between them. The absorber fence prevents diffraction by the subreflector and spillover by the feed from illuminating the main reflector and target zone. System performance is analyzed with and without the absorber fence to show how the coupling aperture should be shaped to minimize diffractions. >

A method to measure the aperture field and experimentally determine the near-field phase center of a horn antenna

A method whereby the aperture field distribution of a horn antenna can be measured is proposed. The method is based on the measurement of the scattered field of a small conducting sphere in the aperture. The position of the phase center of the aperture field is calculated using the measured phase distribution of the field in the aperture via a simple type of convolution. In principle, the method is suited to determine the field distribution of other types of apertures illuminated by an electromagnetic field. >

E-plane analysis of a modified horn antenna with suppressed far-out sidelobe level

It is shown that the far-out sidelobes of a horn antenna can be suppressed by curving the edges in the aperture. A three-dimensional uniform geometrical theory of diffraction (UTD) analysis of the E-plane radiation pattern of the modified horn antenna was performed and compared with straight edges. This analysis indicates that the curvature of the edges does indeed influence the sidelobes to the effect that the modified horn antenna has significantly lower far-out sidelobes. The radiation patterns for modified horns were measured and compared with the calculated patterns and were found to be in good agreement. >