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Peter Griffiths was born and raised in England, spending the first 25 years of his life there. His formal education includes a BA in 1964 and DPhil in physical chemistry [...]

We specify and estimate a model of the early employment growth of technology-driven new ventures. Our estimated model is derived from labor demand theory. A data set of 100 German firms is used to conduct this analysis. The study's findings support the relevance of the theory as applied to these nascent firms. Employment growth is significantly enhanced in ventures exhibiting high profits, experienced founders, formal information processes, and outsourced product distribution. Our findings also confirm aspects of Penrose's theory of firm growth suggesting that transactions costs associated with larger founder teams may inhibit employment growth.

The positive influence of advanced research and development on a country's technological and traditional manufacturing sectors is analyzed, by focusing on South Asian country Taiwan.

A study is conducted to examine the way learning intent, opportunities to learn, and a firmEs ability to learn facilitate or hinder three alliance outcomes, namely, knowledge acquisition by the firm local, knowledge loss to the partner, and alliance satisfaction, focusing on the organizational learning and transition cost economies (TCE) concept. It is concluded that a partnerEs learning intent and ability are positively associated with the extent to which a firm protects its own firm-specific knowledge, but they have only significant effects on one alliance outcome, knowledge loss.

Byline: Martine Spence (1) Keywords: internationalisation; high-technology small companies; overseas strategy Abstract: For some companies, especially in the high technology sector, internationalisation is no longer a matter of choice, but of necessity. This paper explores the strategy development patterns of internationalising small high-technology companies in an environment where windows of opportunity close quickly. Findings from in-depth interviews suggest that emergent strategies within or outside established networks are likely to trigger small high-technology companies' initial internationalisation. Further overseas expansion is constrained by resource availability. This study demonstrates that internationalisation is an iterative process that happens in a holistic way much more than a systematic one. Rather than trying to fit small and medium enterprises' (SMEs') internationalisation patterns into a stage model, managers and policy-makers should recognise the importance of networks. Training and programs could, therefore, help identify strategic networks of importance for the companies and assist them in both contributing and taking advantage of these. Author Affiliation: (1) University of Ottawa, Ottawa, Ontario, Canada Article History: Registration Date: 06/10/2004

Three student engineering teams are profiled with emphasis on the theory that gender can play an important role in achieving a successful team dynamic. This study partially supports that theory.

The analytic network process (ANP) is presented as a potentially valuable method to support the selection of projects in a research and development (R&D) environment. This paper first discusses the requirements of the R&D project selection problem, which requires the allocation of resources to a set of competing and often disparate project proposals. Among the factors complicating this task is the need to make the decision within the framework of an enterprise's strategic objectives and organizational structure while considering and integrating financial and strategic benefits of each project. The paper discusses the use of the ANP, a general form of Saaty's analytic hierarchy process, as a model to evaluate the value of competing R&D project proposals. A generic ANP model developed by the authors, which includes in its decision levels the actors involved in the decision, the stages of research, categories of metrics, and individual metrics, is presented. The paper concludes with a case study describing the implementation of this model at a small high-tech company, including data based on the actual use of the decision making model. Index Terms--Analytic hierarchy process, analytic network process, multicriteria decision making, project selection, R&D management, R&D projects.

A fuzzy reinforcement learning (FRL) scheme which is based on the principles of sliding-mode control and fuzzy logic is proposed. The FRL uses only immediate reward. Sufficient conditions for the convergence of the FRL to the optimal task performance are studied. The validity of the method is tested through simulation examples of a robot which deburrs a metal surface. Index Terms--Deburring, fuzzy reinforcement learning, hybrid hierarchical control, impedance control, sliding-mode fuzzy control.

We focus on the analysis and design of two different sliding mode observers for dynamic Takagi--Sugeno (TS) fuzzy systems. A nonlinear system of this class is composed of multiple affine local linear models that are smoothly interpolated by weighting functions resulting from a fuzzy partitioning of the state space of a given nonlinear system subject to observation. The Takagi-Sugeno fuzzy system is then an accurate approximation of the original nonlinear system. Our approach to the analysis and design of observers for Takagi-Sugeno fuzzy systems is based on extending sliding mode observer schemes to the case of interpolated multiple local affine linear models. Thus, our main contribution is nonlinear observers analysis and design methods that can effectively deal with model/plant mismatches. Furthermore, we consider the difficult case when the weighting functions in the Takagi--Sugeno fuzzy system depend on the estimated state. Index Terms--Dominant linear models, fuzzy sliding mode observers, interpolation of multiple linear local models, Luenberger fuzzy observers, Takagi-Sugeno (TS) fuzzy systems.

The widespread use of influence diagrams to represent and solve Bayesian decision problems is still limited by the inflexibility and rather restrictive semantics of influence diagrams. In this paper, we propose a number of extensions and adjustments to the definition of influence diagrams in order to make the practical use of influence diagrams more flexible and less restrictive. In particular, we describe how deterministic relations can be exploited to increase the flexibility and efficiency of representing and solving Bayesian decision problems. The issues addressed in this paper were motivated by the construction of a decision support system for mission management of unmanned underwater vehicles (UUVs). Index Terms--Deterministic relations, influence diagrams, mission management.

This paper proposes a network routing method based on a computational ecology model. The computational ecology model is a mathematical model proposed by Huberman and Hogg, which represents a macro action of multi-agent systems. We formulate routing on a computer network as a resource allocation problem, where packets and links are regarded as agents and resources, respectively. Then, we apply an extended computational ecology model for this problem. Agents conflict so as to get more payoffs from links. As a result, they get the same payoffs, and a good resource allocation is achieved. In each node, each packet selects a link according to the selection rate decided through conflicts, and routing is accomplished autonomously with adaptability on the computer network. Moreover, we improve fault-tolerance of the system by local information exchanges. Finally, we examine the efficiency of the proposed method by computer simulation. Index Terms--Computational ecology, computer network, distributed control, fault-tolerance, routing.

Approximate reasoning in a fuzzy system is concerned with inferring an approximate conclusion from fuzzy and vague inputs. There are many ways in which different forms of conclusions can be drawn. Fuzzy sets are usually represented by fuzzy membership functions. These membership functions are assumed to have a clearly defined base. For other fuzzy sets such as intelligent, smart, or beautiful, etc., it would be difficult to define clearly its base because its base may consist of several other fuzzy sets or unclear nonfuzzy bases. In this paper, a method to handle this kind of fuzzy set is proposed. A fuzzy neural network (FNN) is also proposed to tune knowledge representation parameters (KRPs). The contributions are that we are able to handle a broader range of fuzzy sets and build more powerful fuzzy systems so that the conclusions drawn are more meaningful, reliable, and accurate. An experiment is presented to demonstrate how our method works. Index Terms--Certainty factors, fuzzy neural networks (FNNs), fuzzy production rules, local weights.

This paper describes a novel design of a robot tactile sensor, called hybrid tactile sensor, based on analog resistive technology. The design employs a set of parallel analog resistive sensing strips, rather than a two-dimensional (2-D) grid of sensing elements, to sample the sensor surface. It is therefore analog in one dimension and discrete in the other. As a result, the number of samples that need to be obtained is significantly reduced, as is the number of connectors in the sensor circuitry. In addition, the sensor design scales easily to a large sensing surface area, and offers flexibility in sensor geometry. However, only the contact location and shape can be sensed, but not the contact force. This paper provides the theoretical model of the sensor, and presents simulation and experimental results. Index Terms--Analog resistive, robotics, tactile sensing, touch sensing.

We present an objective approach for evaluating probability and structure elicitation methods in probabilistic models. The main idea is to use the model derived from the experts' experience rather than the true model as the standard to compare the elicited model. We describe a general procedure by which it is possible to capture the data corresponding to the expert's beliefs, and we present a simple experiment in which we utilize this technique to compare three methods for eliciting discrete probabilities: 1) direct numerical assessment, 2) the probability wheel, and 3) the scaled probability bar. We show that for our domain, the scaled probability bar is the most effective tool for probability elicitation. Index Terms--Bayesian network, evaluation of elicitation methods, learning, probability elicitation.

Cox's Theorem is a widely cited motivation for probabilistic models of uncertain belief. The theorem relates the associativity of the logical connectives to that of the arithmetic operations of probability. Recent questions about the correctness of Cox's Theorem have been resolved, but there are new questions about one functional equation used by Cox in 1946. This equation is missing from his later work. Advances in knowledge since 1946 and changes in Cox's research interests explain the equation's disappearance. Other associativity-based motivations avoid functional equations altogether, and so may be more transparently applied to finite domains and discrete beliefs. A discrete counterpart of Cox's Theorem can be assembled from results that have been in the literature since 1959. Index Terms--Cox's Theorem, de Finetti's conjecture, Keynesian probability, qualitative probability.

We introduce the fuzzy measure and discuss its use as a unifying structure for modeling knowledge about an uncertain variable. We show that a large class of well-established types of uncertainty representations can be modeled within this framework. A view of the Dempster--Shafer (D-S) belief structure as an uncertainty representation corresponding to a set of possible fuzzy measures is discussed. A methodology for generating this set of fuzzy measures from a belief structure is described. A measure of entropy associated with a fuzzy measure is introduced and its manifestation for different fuzzy measures is described. The problem of uncertain decision making for the case in which the uncertainty represented by a fuzzy measure is considered. The Choquet integral is introduced as providing a generalization of the expected value to this environment. Index Terms--Decision making, entropy, fuzzy measure, uncertainty.

We keep learning more about the history of noise calculations. It seems that the topic of the noise of a spectrum in the constant-detector-noise case was addressed more than 50 […]

Information regarding implementation of filters for bidirectional frequency selective filters in cases where data sequences are short and non stationary is given. A method for dealing with the start up problem is given, being based on its computational efficient.

Research into phase stability in frequency-multiplying gyro-traveling wave-tubes is presented. A theoretical and experimental analysis of phase sensitivity of wave-tubes is offered.

Research into the development of a 3-terminal band-to-band tunneling model for use in metal oxide semi conductor field effect transistors is presented. The model offers analysis of the gate-induced drain leakage current.

A study of the threshold hysteresis or memory window of a ferroelectric capacitor and a p-n diode is presented. Investigation shows a memory window width of 2.7V when observed by capacitance-voltage measurement.

Research into the fabrication of complementary metal oxide semiconductors of less than 0.1 micronm is presented. The paper demonstrates the use of key processes such as lateral local super-steep channel doing using heavy ion implantation.

Research into the prediction of oxide breakdown from current measurements at low voltage and at room temperature is presented. A new method correlating oxide breakdown and tunneling into near-interface traps is produced.

Research into the fabrication of a three dimensional complementary metal oxide semiconductor circuit is presented. The paper describes the use of metal-induced lateral crystallization, to build a high performance 3-D circuit.

Research into the design of a model which removes frequency-dependence of drain-source resistance in field effect transistors is presented. A substrate model, using parallel RC circuits connected to the drain junction capacitance, is proposed.

Research into time-dependent dielectric breakdown between copper interconnections is presented. Experiments showed that the NH3- plasma treatment of copper improves dielectric breakdown lifetime and reduces wiring resistance.

Research into composite emitters in GaInP/GaAs heterojunction bipolar transistors is presented. The improvements in high frequency performance and emitter transit time and decreases in base-emitter capacitance are studied.

Research into the design and fabrication of a pseudomorphic high electron mobility transistor is presented. The performance of the device at temperatures from 300 to 450K and gate-to-drain voltage are analysed.

This study was used to examine rates and extents of phenanthrene desorption as functions of sorbent type, initial loading level and aging. The article is broken down into an introduction, a discussion of the experiment and a discussion of the results. Various tables and graphs accompany the article.