bluuebunny/crossref_metadata_2025_split huggingface dataset:
Active suspension for single wheel station of off‐road track vehicle
Authors: Liberzon A. , Rubinstein D. , Gutman P. O. 
Published: August 2002

AbstractThe main objective of ground vehicle suspension systems is to isolate a vehicle body (sprung mass) from road irregularities in order to maximize passenger ride comfort, control the attitude of the vehicle on the road, and retain continuous road–wheel contact in order to provide vehicle holding quality. An appropriate active suspension design must resolve the inherent tradeoffs between ride comfort, road holding quality, and suspension travel. In this study, a robust controller for the active suspension of an off‐road, high‐mobility tracked vehicle is designed, for the first time, using quantitative feedback theory (QFT). A simulation model of a single suspension unit of the M‐113 armored personnel carrier vehicle was used to achieve a proper active suspension design. Two measured states of the 3‐degrees‐of‐freedom mathematical model were used as feedback signals in a cascaded SISO control system. The nonlinear dynamics of the tracked vehicle suspension unit was represented as a set of linear time invariant (LTI) transfer functions, which were identified with the Fourier integral method. Computer simulations of the vehicle with passive and active suspension systems over different terrain profiles are provided. A significant reduction of the vertical accelerations induced to the sprung mass (e.g., ride comfort improvement) was achieved while keeping the road‐arm between suspension travel limits (e.g., handling quality). Copyright © 2001 John Wiley & Sons, Ltd.
Parallel collision detection between moving robots for practical motion planning
Authors: Pérez‐Francisco Miguel , Del Pobil Angel P. , Martínez‐Salvador Begoña 
Published: August 2002

AbstractMotion planning has made few inroads into practical applications in the real world. Practical motion planning involving multiple moving objects with complex geometries requires very fast collision detection. We present an approach to collision detection between moving robots for motion planning. It is based on a spherical hierarchy of detail for nonconvex and curved objects that need not be partitioned into convex ones. We present results that show the stability of the approach regarding the number of polygons used to model the scene. Numerical evidence of the algorithm's efficiency is also shown by several experiments, in which we obtain average intersection detection times of around 1 ms using eight processors for two closely moving robots involving 1900 polygons. © 2001 John Wiley & Sons, Inc.
Random lifts of graphs: Independence and chromatic number
Authors: Amit Alon , Linial Nathan , Matoušek Jiří 
Published: August 2002

AbstractFor a graph G, a random n‐lift of G has the vertex set V(G)×[n] and for each edge [u, v] ∈ E(G), there is a random matching between {u}×[n] and {v}×[n]. We present bounds on the chromatic number and on the independence number of typical random lifts, with G fixed and n→∞. For the independence number, upper and lower bounds are obtained as solutions to certain optimization problems on the base graph. For a base graph G with chromatic number χ and fractional chromatic number χf, we show that the chromatic number of typical lifts is bounded from below by const ⋅ \documentclass{article}\pagestyle{empty}\begin{document}$\sqrt{\chi/\log\chi}$ and also by const ⋅ χf/log2χf (trivially, it is bounded by χ from above). We have examples of graphs where the chromatic number of the lift equals χ almost surely, and others where it is a.s. O(χ/logχ). Many interesting problems remain open. © 2002 John Wiley & Sons, Inc. Random Struct. Alg., 20, 1–22, 2002
Shell, Nigeria and the Ogoni. A study in unsustainable development: III. Analysis and implications of Royal Dutch/Shell group strategy
Authors: Wheeler David , Rechtman René , Fabig Heike , Boele Richard 
Published: August 2002

AbstractIn the first two papers of this trilogy we explored the history of the Royal Dutch/Shell group both internationally and locally in Nigeria. We described a catastrophic failure in relations with the Ogoni and the consequent fall‐out with NGOs and opinion formers more globally. In response to these events Shell embarked on a revision of its business principles and initiated a multi‐million dollar exercise in stakeholder outreach and communication. We also explored the limitations of a purely instrumental approach to ‘stakeholder management’ in Nigeria and suggested that a rights‐based approach might provide a more useful framework for managing relationships and achieving reconciliation between Shell and the Ogoni. In this third paper of the trilogy we explore Shell's current approach to strategy formulation and implementation in the context of what this means for Shell's ability to pursue the ideal of sustainable development. We apply two models for testing the level of integration of business strategy with sustainability and we observe that, whilst Shell's business principles and corporate strategy now embrace notions of market sensitivity and internal and external accountability to an unprecedented degree, the company has yet to maximize opportunities arising from its approach to sustainability and stakeholder responsiveness at the business unit level in Nigeria. Copyright © 2001 John Wiley & Sons, Ltd. and ERP Environment
Tailored colloidal AFM probes and their TEM investigation
Authors: Hüttl Grit , Klemm Volker , Popp Roswitha , Simon Frank , Müller Eberhard 
Published: August 2002

AbstractThe use of an individual particle attached to the end of a cantilever is the established method for characterizing colloidal interaction forces using an atomic force microscope. In this manner the geometry of the probe is well defined but the difficult handling of particles with diameters <1µm and the restricted availability of different materials as ideal spheres of the desired size and low roughness limit the variability of this method.We propose a method to adjust the tip radius of commercial silicon tips from ∼30 nm up to 2 µm by an oxidation procedure. The resulting silica tips have ideal (hemi‐)spherical geometry and very low roughness. It is possible to vary the surface composition and properties by combining the oxidation procedure with a coating or chemical modification process.A home‐made transmission electron microscopy holder make it possible to analyse easily and very precisely the tip radius and the thickness of layers of different materials without destruction of the system cantilever chip. This means that the probe can be analysed before and after an atomic force microscopy measurement. Copyright © 2002 John Wiley & Sons, Ltd.
An improved CML estimation procedure for the Rasch model with item response data
Authors: Sheng Xiaoming , Carrière K. C. 
Published: August 2002

AbstractOrdinal response data are commonly observed in health and medical investigations that include several items. The primary goal in the modelling of item response data is to find a unique measurement of the person's abilities and of the item difficulties that satisfies the properties of the fundamental measurement. One such analytic method in item response theory is the Rasch measurement, which is a way to convert ordinal observations into linear measures. Current estimation strategies assume the independence of the Rasch model parameters. In this paper, based on the conditional maximum likelihood, we implemented a simultaneous estimation method that can compare the Rasch parameters more efficiently. We also obtained the asymptotic properties of these estimators and developed the conditional likelihood ratio test for the goodness‐of‐fit of the model. Simulation studies were used to demonstrate the improved performance of our estimators as compared to that of currently used conditional method known as the CON procedure. We conclude that our estimation method outperforms CON in both model fit and the precision of the Rasch estimators. Copyright © 2002 John Wiley & Sons, Ltd.
Detecting and eliminating erroneous gestational ages: a normal mixture model
Authors: Platt Robert W. , Abrahamowicz Michal , Kramer Michael S. , Joseph K. S. , Mery Les , Blondel Béatrice , Bréart Gérard , Wen S. W. 
Published: August 2002

AbstractIn perinatal research and clinical practice, gestational age is a crucial variable for measuring foetal ‘growth’ (birth weight for gestational age) and for estimating the risk of mortality and morbidity, yet reported gestational age values are affected by random and systematic errors due to the absence of a gold standard measure. Previous investigators have used birth weight (which is measured with greater validity and precision than is gestational age) to correct such errors, but existing methods are inadequate due to unreasonable assumptions about the distributions of birth weight and gestational age. We propose a new method for identifying and correcting implausible observations using the expectation‐maximization (EM) algorithm. Using population‐based data from U.S. birth certificates, we compare the resulting gestational ages, birth weight distributions at each gestational age, and gestational age‐specific infant mortality based on the new method with those on the same population produced by previous published correction methods. The new method gives the best birth weight distributions for gestational age and the most realistic gestational‐age‐specific mortality rates, while each of the other methods has at least one significant flaw. Copyright © 2001 John Wiley & Sons, Ltd.
Statistical issues in bioequivalance
Authors: Senn Stephen 
Published: August 2002

AbstractThere has been much work recently on individual bioequivalence and the topic has attracted considerable controversy. Some previous controversies regarding average bioequivalence are examined. It is argued that a contributory factor in these controversies may have been confusion over the purpose of bioequivalence trials. It is concluded that this purpose needs further clarification before guidelines for individual bioequivalence can be established and indeed that such guidelines may turn out to be unnecessary. Copyright © 2001 John Wiley & Sons, Ltd.
Value creation in E‐business
Authors: Amit Raphael , Zott Christoph 
Published: August 2002

AbstractWe explore the theoretical foundations of value creation in e‐business by examining how 59 American and European e‐businesses that have recently become publicly traded corporations create value. We observe that in e‐business new value can be created by the ways in which transactions are enabled. Grounded in the rich data obtained from case study analyses and in the received theory in entrepreneurship and strategic management, we develop a model of the sources of value creation. The model suggests that the value creation potential of e‐businesses hinges on four interdependent dimensions, namely: efficiency, complementarities, lock‐in, and novelty. Our findings suggest that no single entrepreneurship or strategic management theory can fully explain the value creation potential of e‐business. Rather, an integration of the received theoretical perspectives on value creation is needed. To enable such an integration, we offer the business model construct as a unit of analysis for future research on value creation in e‐business. A business model depicts the design of transaction content, structure, and governance so as to create value through the exploitation of business opportunities. We propose that a firm's business model is an important locus of innovation and a crucial source of value creation for the firm and its suppliers, partners, and customers. Copyright © 2001 John Wiley & Sons, Ltd.
The structure of ownership and corporate acquisition strategies
Authors: Wright Peter , Kroll Mark , Lado Augustine , Van Ness Bonnie 
Published: August 2002

AbstractIn this study, we examine in an agency‐theoretic context the influence of executive equity stakes upon corporate strategy and firm value. We argue that beneficial, risk‐increasing corporate strategies may initially be emphasized but non‐value‐maximizing, risk‐reducing strategies may subsequently be emphasized as managers expand their stock ownership. We alternatively contend that stock options may have a consistently positive impact on firm risk taking and acquisition returns. The empirical findings are supportive of our expectations. Copyright © 2002 John Wiley & Sons, Ltd.
The persistence of knowledge‐based advantage: an empirical test for product performance and technological knowledge
Authors: McEvily Susan K. , Chakravarthy Bala 
Published: August 2002

AbstractResource‐based theory maintains that intrinsic characteristics of resources and capabilities, such as their tacitness, complexity, and specificity, prevent imitation and thereby prolong exceptional performance. There is little direct evidence to verify these claims, yet a substantial literature encourages firms to formulate competitive strategies around resources with these attributes. Further, work outside the resource‐based tradition suggests that these attributes can slow innovation, and it is not clear when this effect outweighs the benefits of inimitability. This paper seeks to clarify whether and how the complexity, tacitness, and specificity of a firm's knowledge affect the persistence of its performance advantages. We find that the complexity and tacitness of technological knowledge are useful for defending a firm's major product improvements from imitation, but not for protecting its minor improvements. The design specificity of technological knowledge delayed imitation of minor improvements in this study. Copyright © 2002 John Wiley & Sons, Ltd.
Value creation in fine arts: a system dynamics model of inverse demand and information cascades
Authors: Crossland Philip , Smith faye l. 
Published: August 2002

AbstractWe integrate information cascades and demand queue behaviors as they affect the distribution of marginal value added in the value chain. We develop a system dynamics model of the relationships of Edward Marshall Boehm, Inc., a studio that creates hard‐paste porcelain pieces of fine art sculpture. The relationships between information cascades, demand queues, and the distribution of marginal value added are applicable to other fine art settings and other industries. Copyright © 2002 John Wiley & Sons, Ltd.
Taking Syntegrity‐4 from assumption mode to reflection mode
Authors: Holmberg Stig C. 
Published: August 2002

AbstractA model, Syntegrity‐4, for competence development in small and medium‐seized enterprises (SMEs) is designed. Syntegrity‐4 builds on the assumptions that competence development is a continuous activity that is best undertaken in a network with cooperation between different types of actors. Further, it is presumed that systemics and informatics have much to provide in increasing the skills of individual workers as well as the workforce as a whole. In working with the employees in a number of enterprises those assumptions have at large proven to be correct. However, the methodology in its present form is not good enough. No drastic and long‐lasting positive effects could be observed in the cooperating enterprises. Hence, a group of further steps for improving and complementing Syntegrity‐4 are identified. Copyright © 2001 John Wiley & Sons, Ltd.
The forgotten revenue of product development: learning new competence
Authors: Österlund Jan 
Published: August 2002

AbstractThe result of a new product development (NPD) process is not only a new product of desired quality but also learning new competence from problem‐solving experience. The learning results in a core competence, unique to the company, that makes it competitive in the future. Research results show that groups of specialists develop core competencies through learning by experience from joint problem solving at the technological front line. Specialists in a particular field, talking the same professional language, act as a living system in a self‐organizing group. Primarily individuals make experiences as tacit knowledge. It is then confirmed in a dialogue with colleagues in the specialist group to which the individual belongs. However, providing competence resources to high‐technology projects of a complex nature requires cross‐disciplinary teamwork. Therefore the knowledge from experience has to be transferred to a form that the entire organization can comprehend. This requires a creative learning process of innovating new concepts that all organization members concerned understand and find useful. To be successful, such a learning process must rely on a culture supporting it by an atmosphere of openness and innovativeness. It is therefore a managerial task to foster a supporting culture by giving suitable information to all levels of the company. Copyright © 2001 John Wiley & Sons, Ltd.
Creative distortions and social improvements
Authors: Soudijn Karel 
Published: August 2002

AbstractResearch in the field of psychotherapy is dominated by a medical metaphor, giving rise to standardized procedures which restrict interaction between therapist and client in a way that may often be deemed as counter‐productive. Conversations with Gerard de Zeeuw suggested alternative procedures for gathering information to enhance the development of psychotherapeutic interventions. This approach to research may be labelled as a kind of interactional perspectivism. The paper itself may be read as a personal reflection on de Zeeuw's teachings about developing a more social view on improvement. Copyright © 2002 John Wiley & Sons, Ltd.
Pathologic analysis of sentinel lymph nodes
Authors: van Diest Paul J. , Torrenga Hans , Meijer Sybren , Meijer Chris J.L.M. 
Published: August 2002

AbstractThe sentinel lymph node (SLN) procedure enables selective targeting of the first draining lymph node, where the initial metastases will form. A negative SLN predicts the absence of tumor metastases in the other regional lymph nodes with a high degree of accuracy. This means that in case of a negative SLN, regional lymph node dissection is no longer necessary. Besides saving patients the significant morbidity associated with lymph node dissection, it will also save costs.Crucial for the success of the SLN procedure is the screening of the SLN for metastases by the pathologist. To this end, several techniques are available such as standard histo‐ and cytopathological techniques, immunohistochemistry, flow cytometry, and molecular biological techniques. In this paper, the value of these methods for detecting SLN metastases is discussed. Some of these techniques have also appeared to be quite useful for intraoperative evaluation of SLNs.The standard protocol for detection of SLN metastases consists of extensive histopathological investigation including stepped sections stained with hematoxylin and eosin (HE) and immunohistochemistry. Intraoperative frozen section analysis and imprint cytology of SLNs have been shown to be reasonably reliable for detecting breast cancer metastases in SLNs. Further studies are necessary to establish the role of multiparameter flow cytometry and sophisticated molecular biological techniques such as reverse transcription polymerase chain reaction (RT‐PCR) in detecting SLN metastases. Semin. Surg. Oncol. 20:238–245, 2001. © 2001 Wiley‐Liss, Inc.
An active tendon control scheme for cable‐stayed bridges with model uncertainties and seismic excitation
Authors: Rodellar J. , Mañosa V. , Monroy C. 
Published: August 2002

AbstractThis paper proposes an active scheme for vibration control of cable‐stayed bridges under seismic loads. The control action is supplied by using a subset of the stay cables as active tendons. The dynamic model of the bridge is decomposed into two coupled subsystems, one of them including the degrees of freedom that are directly influenced by the active tendons. A linear control law is proposed to drive the active tendons via feedback of the states of these degrees of freedom only. A stability analysis gives conditions to ensure the existence of a ball of ultimate boundedness for the whole bridge model in the presence of a class of uncertainties in the model parameters and the seismic excitation. The effectiveness of the control scheme is shown numerically on a finite element model of a pedestrian cable‐stayed bridge Copyright © 2002 John Wiley & Sons, Ltd.
Critical role of α1‐adrenergic receptors in acute and sensitized locomotor effects of D‐amphetamine, cocaine, and GBR 12783: Influence of preexposure conditions and pharmacological characteristics
Authors: Drouin Candice , Blanc Gérard , Villégier Anne‐Sophie , Glowinski Jacques , Tassin Jean‐Pol 
Published: August 2002

AbstractPsychostimulant‐induced locomotor hyperactivity is commonly associated with an inhibition of dopamine reuptake. However, a physiological coupling between noradrenergic and dopaminergic neurons occurring through the stimulation of α1‐adrenergic receptors has recently been proposed. This possibility was tested on locomotor responses induced either by D‐amphetamine and cocaine, which both interfere with noradrenergic and dopaminergic transmissions, or by GBR 12783, a specific dopamine reuptake inhibitor. In an attempt to control the effects of stress and novelty on noradrenergic neurons activity, rats were submitted to habituation procedures consisting of either a 15‐h period of habituation to the experimental environment (“long‐habituation”) or to repeated exposure to intraperitoneal saline injections for 3 consecutive days (“three‐session”). Three‐session‐exposed animals exhibited a pronounced locomotor reactivity to saline injection which did not occur after noradrenergic depletion, clonidine (20 μg/kg) or prazosin (0.5 mg/kg) pretreatments, or in long‐habituation‐preexposed animals. Cocaine and GBR 12783 locomotor hyperactivities were doubled in three‐session vs. long‐habituation‐preexposed rats, whereas D‐amphetamine responses were similar in both conditions. Prazosin (0.5 mg/kg) pretreatment reduced the acute locomotor effects of the three psychostimulants in both procedures and blocked the behavioral sensitization induced by repeated injections of D‐amphetamine (0.75 mg/kg) or cocaine (5 mg/kg). GBR 12783 (5 mg/kg) failed to induce significant behavioral sensitization. In addition to their role in the acute and sensitized locomotor responses to psychostimulants possessing different pharmacological characteristics, α1‐adrenergic receptors are involved in animal reactivity to previously experimented procedures. This suggests an implication of noradrenergic neurons in the vulnerability to psychostimulants. Synapse 43:51–61, 2002. © 2001 Wiley‐Liss, Inc.