bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lyapunov‐Krasovskii functionals for additional dynamics
Authors: Kharitonov Vladimir L. , Melchor‐Aguilar Daniel 
Published: June 2003

AbstractA class of Lyapunov–Krasovskii functionals for the additional dynamics introduced by special transformation of time delay systems is given in the paper. Some basic properties of the functionals are also discussed. Copyright © 2003 John Wiley & Sons, Ltd.
An improved stability criterion for systems with distributed delays
Authors: Gu Keqin 
Published: June 2003

AbstractThis article improves the formulation of discretized Lyapunov functional method for systems with distributed delays. The main idea is to apply Jensen's inequality and variable elimination in matrix inequalities. The resulting stability criterion is much simpler. Experience in numerical calculation indicates that it generally converges to the analytical result as grid size decreases, and the speed of convergence is much faster than the previous method. The new formulation is also applicable to a wider class of systems. Copyright © 2003 John Wiley & Sons, Ltd.
Finite‐dimensional characterizations ofH∞control for linear systems with delays in input and output
Authors: Uchida K. , Ikeda K. , Azuma T. , Kojima A. 
Published: June 2003

AbstractWe formulateH∞control problems for linear systems with delays in input and output, and discuss possibility of finite‐dimensional characterizations of solutions. In the case when delay exists in control input and controlled output, first, we derive an output feedbackH∞control formula of the central solution type, which is given by using solutions of finite‐ and infinite‐dimensional Riccati matrix inequalities. Second, we show that, if the controlled output is chosen such that it satisfies the ‘prediction condition’, the solution to the infinite‐dimensional Riccati inequality can be calculated by solving a finite‐dimensional Riccati inequality. We provide a system theoretic interpretation for the prediction condition, and show that, if the prediction condition is satisfied, there is an equivalentH∞control problem for finite‐dimensional linear systems with no delay. Finally, the equivalence result is extended to the case when delay exists also in measurement output. Copyright © 2003 John Wiley & Sons, Ltd.
Adaptive identification of linear time‐delay systems
Authors: Orlov Y. , Belkoura L. , Richard J.P. , Dambrine M. 
Published: June 2003

AbstractSynthesis of an adaptive parameter identifier is developed for linear dynamic systems with finitely many lumped delays in the state vector and control input. These systems are governed by linear functional differential equations with uncertain time‐invariant parameters and delays. The state of the system is assumed to be available for measurements. Constructive necessary and sufficient conditions for the system parameters and delays to be identifiable are provided. Once the parameter identifiability is guaranteed the simultaneous on‐line identification of the system parameters and delays is achieved by the adaptive identifier proposed. Theoretical results are supported by numerical simulation. Copyright © 2003 John Wiley & Sons, Ltd.
Bilateral teleoperation with communication delays
Authors: Niculescu Silviu‐Iulian , Taoutaou Damia , Lozano Rogelio 
Published: June 2003

AbstractThis paper focuses on the closed‐loop stability analysis of a teleoperation control scheme subject to time‐delays in the communication channel. The stability conditions derived using a frequency‐domain approach areanalyticaland easy to check.Delay‐independentas well as variousdelay‐intervalsstability cases are treated. The novelty of the approach lies in its simplicity for characterizing the stability regions in terms of the systems' parameters. Physical interpretations are included, and a simple example is presented. Copyright © 2003 John Wiley & Sons, Ltd.
Regional stabilization andH∞control of time‐delay systems with saturating actuators
Authors: Fridman E. , Pila A. , Shaked U. 
Published: June 2003

AbstractA linear parameter varying approach is introduced for the design of a constant state‐feedback controller that locally stabilizes linear systems with state time‐varying delays and saturating actuators and achieves a prescribed performance level for all disturbances with uniformly bounded magnitudes. A polytopic representation is used to describe the saturation behaviour. Delay‐dependent sufficient conditions in terms of linear matrix inequalities (LMIs) are obtained for the existence of such a controller. An estimate is made of the domain of attraction for the disturbance‐free system. The conditions for the stabilizability andH∞performance of the system apply the Lyapunov–Krasovskii functional and the recent descriptor approach to the control of time‐delay systems, whereas the conditions for finding an ellipsoid that bounds the set of the states (in the Euclidean space) that are reachable from the origin in finite time are obtained via the Razumikhin approach. The resulting conditions are expressed in terms of linear matrix inequalities, with some tuning parameters, and they apply a different Lyapunov function to each of the vertex points that stem from the polytopic description of the saturation in the actuators. Copyright © 2003 John Wiley & Sons, Ltd.
Input‐output linearization with delay cancellation for nonlinear delay systems: the problem of the internal stability
Authors: Germani A. , Manes C. , Pepe P. 
Published: June 2003

AbstractThis paper investigates the issue of the internal stability of nonlinear delay systems controlled with a feedback law that performs exact input–output, linearization and delay cancellation. In previous works the authors showed that, unlike with the case of systems without state delays, when the relative degree is equal to the number of state variables and the output is forced to be identically zero, delay systems still possess a non‐trivial internal state dynamics. Not only, in the same conditions delay systems are also characterized by a non‐trivial input dynamics. Obviously, both internal state and input dynamics should give bounded trajectories, otherwise the exact input–output linearization and delay cancellation technique cannot be applied. This paper studies the relationships between the internal state and input dynamics of a controlled nonlinear delay system. An interesting result is that a suitable stability assumption on the internal state dynamics ensures that, when the output is asymptotically driven to zero, both the state and control variables asymptotically decay to zero. Copyright © 2003 John Wiley & Sons, Ltd.
Persistent heterogeneity and sustainable innovation
Authors: Knott Anne Marie 
Published: June 2003

AbstractOne of the concerns with strategy as a field is that its goal (durable profits) appears at odds with that of microeconomics (homogeneous firms with zero profits). Thus even if we can find sources of durable profits, maybe we shouldn't—because doing so comes at the expense of social welfare. In this sense, strategy is an ‘economic bad.’ Probably the most vivid evidence of this tension is the fact that Porter's Competitive Strategy (1982) is Industrial Organization turned on its head—exploiting indications of anti‐competitive behavior to create prescriptions for durable profits. This study presents a parallax view in which the field of strategy is an economic good. In this view, heterogeneity stimulates innovation and economic growth. The underlying logic is that heterogeneity fuels diffusion; diffusion erodes leaders' shares; the loss of shares stimulates innovation, which in turn fuels new diffusion. I develop this view through a simple model of firms embedded in an industry, and then evaluate the model via simulation. The key issue for the model is whether there are steady states that sustain heterogeneity and innovation. Results indicate that heterogeneity persists in roughly half the industry conditions I examined. Furthermore innovation and growth are sustained under those conditions. What is comforting about the set of conditions is that they accommodate (and indeed require) all the things we hold dear: industrial policy, and strategic as well as routine behavior by firms. The new insights are as follows: (1) heterogeneity fuels growth (thus ‘strategy’ is an economic good, rather than anathema to allocative efficiency); (2) persistent heterogeneity is feasible even in the presence of spillovers (without isolating mechanisms); (3) but this heterogeneity (while persistent) requires managers to actively preserve the inherent value of their resource advantages—firms can't rest on their laurels; (4) policy prescriptions differ from those of prior innovation models. Copyright © 2003 John Wiley & Sons, Ltd.
The persistence of founder influence: management, ownership, and performance effects at initial public offering
Authors: Nelson Teresa 
Published: June 2003

AbstractThe purpose of this research is to apply a conceptual framework to questions of how, why, and when founders participate in the firms that they establish and to empirically test for the persistent influence of the founder on the firm after start‐up. A definition of the term ‘founder’ is proposed. Empirical tests compare firms with founder CEOs to those with nonfounder CEOs to determine whether governance and ownership relationships are distinguishable at initial public offering (IPO). In addition, investor reaction to founder‐led firms at IPO is tested. Results suggest that founder influence does persist in governance and ownership arrangements and that the stock market reaction to founder‐led firms is higher than for the comparison group, relative to accounting value. Copyright © 2003 John Wiley & Sons, Ltd.
Measuring organizational knowledge: a conceptual and methodological framework
Authors: Wilcox King Adelaide , Zeithaml Carl P. 
Published: June 2003

AbstractKnowledge is fundamental to strategic success. Limited progress has been made, however, in measuring organizational knowledge. We employ research on resource‐based theory and organizational epistemology to suggest a perceptual approach to measuring knowledge. We present a research protocol to identify a domain of organizational knowledge resources within industries. Using a sample of organizations from the hospital and textile industries, we interviewed CEOs to identify the feasible set of knowledge resources. We presented this set to managers at those organizations to measure their perceptions of the value‐added of each knowledge resource for their organizations. The results demonstrate that the importance of knowledge resources varies by industry and organization, and calls to question efforts to generate an inventory of generic knowledge resources that is applicable across industries. Copyright © 2003 John Wiley & Sons, Ltd.
Diversification in context: a cross‐national and cross‐temporal extension
Authors: Mayer Michael , Whittington Richard 
Published: June 2003

AbstractThis research note examines the stability of diversification performance relationships in three countries (France, Germany and the United Kingdom), for two time periods (1982–84 and 1992–94). The aggregate findings, taking the three countries and two time periods together, support a general model favoring related‐constrained diversification. However, disaggregated analyses show sharp variations in different countries and time periods. The note concludes that although broad performance relationships can be found, these can be expressed very differently in particular contexts. We consider implications for further research. Copyright © 2003 John Wiley & Sons, Ltd.
Chief executive scanning emphases, environmental dynamism, and manufacturing firm performance
Authors: Garg Vinay K. , Walters Bruce A. , Priem Richard L. 
Published: June 2003

AbstractChief executives must allocate their scarce time for scanning efforts among relevant domains of their firms' external environment and their firms' internal circumstances. We argue that high‐performing CEOs vary their relative scanning emphases on different domains according to the level of dynamism they perceive in their external environments. The concepts of dominant logic and sector importance were used to develop predictions about which external domains and which internal domains should receive relatively more or less scanning emphasis in external environments that, overall, are more dynamic or more stable. A field survey of 105 single‐business manufacturing firms evaluated CEOs' scanning emphases and firm performance. Results indicated that, for dynamic external environments, relatively more CEO attention to the task sectors of the external environment and to innovation‐related internal functions was associated with high performance. In stable external environments, however, simultaneously increased scanning of the general sectors in the external environment and efficiency‐related internal functions produced higher performance. These relationships were strongest between relative scanning emphases among domains and sales growth. We discuss the implications of these results for researchers and practitioners. Copyright © 2003 John Wiley & Sons, Ltd.
IT competency and firm performance: is organizational learning a missing link?
Authors: Tippins Michael J. , Sohi Ravipreet S. 
Published: June 2003

AbstractMany companies have developed strategies that include investing heavily in information technology (IT) in order to enhance their performance. Yet, this investment pays off for some companies but not others. This study proposes that organization learning plays a significant role in determining the outcomes of IT. Drawing from resource theory and IT literature, the authors develop the concept of IT competency. Using structural equations modeling with data collected from managers in 271 manufacturing firms, they show that organizational learning plays a significant role in mediating the effects of IT competency on firm performance. Copyright © 2003 John Wiley & Sons, Ltd.
Self‐guided/conscious evolution
Authors: Banathy Bela H. 
Published: June 2003

AbstractI start out by mapping the evolutionary journey of our species. I focus on the cultural evolution of the last 50,000 years of our seven million year journey. Studying the journey I have learned how evolution has worked in the evolutionary design space and what its principles and rules are. This led me to attain evolutionary consciousness. Evolutionary consciousness became the springboard to leap into conscious evolution and propose ways and means by which to engage in self‐guided evolution. In closing, I introduce an evolutionary design process, metaphorically called the Agora Project: building new agoras in the 21st century. Copyright © 2002 John Wiley & Sons, Ltd.
The self‐guiding evolution of civilizations
Authors: Elgin Duane 
Published: June 2003

AbstractThe universe is creating self‐organizing and self‐referencing systems at every scale. In accord with this dynamic, the human family is working to become consciously self‐organizing at progressively larger scales. We have evolved from awakening hunter‐gatherers to a species that has created a wired world whose actions are changing the face of the planet. Because the impact of humanity is now global, that is the scale at which we are challenged to become reflective if we are to be choiceful about our common future. We are challenged to no longer ‘run on automatic’, but to pay attention to how we pay attention as entire civilizations. The vehicle of collective attention at a civilizational scale is the mass media—particularly broadcast television. If civilizations are to realize their potential for full reflective consciousness and become self‐guiding in their evolution, then it is vital for the public to mobilize the public's airwaves on behalf of the public interest. Copyright © 2002 John Wiley & Sons, Ltd.
Boundary‐spanning dialogue for the 21st‐century agoras
Authors: Christakis Alexander N. , Brahms Sabrina 
Published: June 2003

AbstractThe paper identifies the critical role dialogue must play in constructing and sustaining the 21st‐century agoras in the context of the Global Village. Recognizing that the trends towards globalization are irreversible, it describes a boundary‐spanning dialogue approach (BDA) as the necessary, but not sufficient, foundation for enabling human beings to conceptualize and materialize the idealization of ‘conscious evolution of humanity’. The approach to BDA described in the paper is based on over 30 years of research, development and testing in the social systems design arena. Many stories from the design arena are available and documented. A major challenge for the agoras of the 21st century will be their capacity to engage multilingual, multicultural and geographically dispersed stakeholders in a boundary‐spanning dialogue among civilizations in the context of the Global Village. Two stories from past applications of BDA in the social systems design arena are presented in this paper. The first story discusses a project in Washington, DC involving Native American leaders and Federal Government executives, in the late 1980s. The second story focuses on a peace‐building workshop between Israelis and Palestinians that was facilitated by members of the bi‐communal Cypriot community. Copyright © 2002 John Wiley & Sons, Ltd.
Conscious evolution: the next stage of human development
Authors: Marx Hubbard Barbara 
Published: June 2003

AbstractConscious evolution is emerging in our generation because humanity has gained the powers of co‐destruction of our world, or the co‐creation of immeasurable futures. The purpose of conscious evolution is to learn how to be responsible for the ethical guidance of evolution. This new world view arises out of three new conditions: the new cosmology, the new crises and our new capacities, leading toward a macroshift. The Foundation for Conscious Evolution is formed to discover and offer a new developmental path to the next stage of human evolution. It offers three projects to serve this purpose: Gateway to our Conscious Evolution, a six‐month online educational program; the development of a conscious evolution community in Santa Barbara and the formation of a ‘Peace Room’ on the web and in localities to scan for, map, connect and communicate what is working to heal and evolve our world. Copyright © 2002 John Wiley & Sons, Ltd.
Cationisation of Glycerol Plasticised Wheat Starch under Microhydric Molten Conditions
Authors: Ayoub Ali , Bliard Christophe 
Published: July 2003

AbstractCationisation of glycerol plasticised wheat starch was performed in a molten mixture under the action of thermo‐mechanical energy using two reagents: 3‐chloro‐2‐hydroxypropyltrimethylammonium chloride and 2‐epoxypropyltrimethylammonium chloride. The reaction was catalysed with sodium hydroxide under microhydric conditions. The results showed that under these conditions the reaction proceeds rapidly and reaches completion within a few minutes. The reaction efficiencies were higher for lower degrees of substitution (DS). The epoxide showed a higher reactivity than the chloro derivative. Both destructurisation of starch granules and increased sodium hydroxide concentration enhanced the reaction, but an increase in plasticiser concentration had a negative effect. Measurements of intrinsic viscosity showed a decrease of the average molecular weight of the product, which was attributed to the thermo‐mechanical melting process. An increase in water affinity with DS was seen in the water sorption properties of the chemically modified starch.
Chemical and Physical Characterisation of Grain Tef [Eragrostis tef (Zucc.) Trotter] Starch Granule Composition
Authors: Bultosa Geremew , Taylor John R. N. 
Published: July 2003

AbstractChemical and physical properties of starch granules isolated from five grain tef (Eragrostis tef) varieties were characterised and compared with those of maize starch. Endogenous starch lipids extracted with hot water‐saturated n‐butanol and total starch lipids extracted with n‐hexane after HCl hydrolysis were 7.8 mg/g (mean) and 8.9 mg/g (mean), respectively, slightly lower than in the maize starch granules. The starch phosphorus content (0.65 mg/g) was higher than that of maize starch but virtually the same as reported for rice starch. The starch granule‐swelling factor was lower than that of maize starch and extent of amylose leaching was higher. The starch X‐ray diffraction pattern was characteristic of A type starch with a mean crystallinity of 37%, apparently lower than the crystallinity of maize starch and more similar to that reported for rice and sorghum starches. The starch DSC gelatinisation temperature was high, like for other tropical cereals; To, Tp, Tc and ΔH were in the range 63.8—65.4, 70.2—71.3, 81.3—81.5 °C and 2.28—7.22 J/g, respectively. The lower swelling, apparently lower percentage crystallinity and lower DSC gelatinisation endotherms than maize starch suggest that the proportion of long amylopectin A chains in tef starch is smaller than in maize starch.
Characteristics of Modified β‐Cyclodextrin Bound to Cellulose Powder
Authors: Rehmann Lars , Yoshii Hidefumi , Furuta Takeshi 
Published: July 2003

AbstractMonochlorotriazinyl‐β‐cyclodextrin (MCT‐β‐CD) was covalently bonded to cellulose powder. The amount of MCT‐β‐CD bonded to cellulose could be determined by infrared spectroscopy. The coupling reaction was characterized as a physical adsorption of the MCT‐β‐CD on the cellulose powder followed by an apparently zero order chemical reaction. The reaction rate constant was found to be k = 6.43 · 10‐4 ± 0.11 · 10‐4 g g‐1 s‐1. The immobilized cyclodextrin was able to include and release d‐limonene as a model flavor compound. The maximum molar inclusion ratio was 0.85, which is the same inclusion ratio as for d‐limonene in native β‐cyclodextrin. The release rates of dlimonene included in the fixed MCT‐β‐CD were monitored at various relative humidities and 50 °C. The release kinetics could be modeled using the Avrami equation. These results demonstrate that flavors as well as other hydrophobic compounds can be included and released from MCT‐β‐CD immobilized on cellulose.
Extraction, Physicochemical and Compaction Properties of Tacca Starch — a Potential Pharmaceutical Excipient
Authors: Kunle Olobayo O. , Ibrahim Yakubu E. , Emeje Martins O. , Shaba Sam , Kunle Yemisi 
Published: July 2003

AbstractSome physicochemical properties of tacca starch (Tacca leontopetaloides, Taccaceae) have been examined and the results compared to those of maize and potato starches. Tacca starch was found to have a higher amylose content than maize starch but a lower content than potato starch. The starch granules were small (average particle size 3.5 μm) relative to maize and potato starches and were predominantly polyhedral with edges. The gelatinisation characteristics except from the temperature were similar to those of maize starch but much higher than those of potato starch. Tacca starch had relatively higher swelling power and solubility than the other starches. Its features in the formation of compacts (tablets) were comparable to those of maize starch with tacca starch being more resistant to deformation.