Alcatel-Lucent

About: Alcatel-Lucent is a based out in Stuttgart, Germany. It is known for research contribution in the topics: Signal & Network packet. The organization has 37003 authors who have published 53332 publications receiving 1430547 citations. The organization is also known as: Alcatel-Lucent S.A. & Alcatel.

Stability theory for hybrid dynamical systems

Abstract: We first formulate a model for hybrid dynamical systems which covers a very large class of systems and which is suitable for the qualitative analysis of such systems. Next, we introduce the notion of an invariant set for hybrid dynamical systems and we define several types of (Lyapunov-like) stability concepts for an invariant set. We then establish sufficient conditions for uniform stability, uniform asymptotic stability, exponential stability, and instability of an invariant set of hybrid dynamical systems. Under some mild additional assumptions, we also establish necessary conditions for some of the above stability types (converse theorems). In addition to the above, we also establish sufficient conditions for the uniform boundedness of the motions of hybrid dynamical systems (Lagrange stability). To demonstrate the applicability of the developed theory, we present specific examples of hybrid dynamical systems and we conduct a stability analysis of some of these examples.

Control of crystal nucleation by patterned self-assembled monolayers

Abstract: An important requirement in the fabrication of advanced inorganic materials, such as ceramics and semiconductors, is control over crystallization1,2,3,4. In principle, the synthetic growth of crystals can be guided by molecular recognition at interfaces5,6,7,8,9,10,11,12,13,14,15,16. But it remains a practical challenge to control simultaneously the density and pattern of nucleation events, and the sizes and orientations of the growing crystals. Here we report a route to crystal formation, using micropatterned self-assembled monolayers17,18, which affords control over all these parameters. We begin with a metal substrate patterned with a self-assembled monolayer having areas of different nucleating activity—in this case, an array of acid-terminated regions separated by methyl-terminated regions. By immersing the patterned substrates in a calcium chloride solution and exposing them to carbon dioxide, we achieve ordered crystallization of calcite in the polar regions, where the rate of nucleation is fastest; crystallization can be completely suppressed elsewhere by a suitable choice of array spacing, which ensures that the solution is undersaturated in the methyl-terminated regions. The nucleation density (the number of crystals formed per active site) may be controlled by varying the area and distribution of the polar regions, and we can manipulate the crystallographic orientation by using different functional groups and substrates.

In vivo dendritic calcium dynamics in neocortical pyramidal neurons

Abstract: The dendrites of mammalian pyramidal neurons contain a rich collection of active conductances that can support Na+ and Ca2+ action potentials (for a review see ref. 1). The presence, site of initiation, and direction of propagation of Na+ and Ca2+ action potentials are, however, controversial, and seem to be sensitive to resting membrane potential, ionic composition, and degree of channel inactivation, and depend on the intensity and pattern of synaptic stimulation. This makes it difficult to extrapolate from in vitro experiments to the situation in the intact brain. Here we show that two-photon excitation laser scanning microscopy can penetrate the highly scattering tissue of the intact brain. We used this property to measure sensory stimulus-induced dendritic [Ca2+] dynamics of layer 2/3 pyramidal neurons of the rat primary vibrissa (Sm1) cortex in vivo. Simultaneous recordings of intracellular voltage and dendritic [Ca2+] dynamics during whisker stimulation or current injection showed increases in [Ca2+] only in coincidence with Na+ action potentials. The amplitude of these [Ca2+] transients at a given location was approximately proportional to the number of Na+ action potentials in a short burst. The amplitude for a given number of action potentials was greatest in the proximal apical dendrite and declined steeply with increasing distance from the soma, with little Ca2+ accumulation in the most distal branches, in layer 1. This suggests that widespread Ca2+ action potentials were not generated, and any significant [Ca2+] increase depends on somatically triggered Na+ action potentials.

Software product-line engineering: a family-based software development process

Abstract: (Each chapter concludes with a Summary, Nomenclature Introduced, and Readings. Foreword. Preface. 1. Introduction: The Need for Families. The Dilemma of Careful Engineering and Rapid Production. Problems FAST Addresses. Applications of FAST. Benefits of FAST. What Can Readers Expect? 2. Family-Oriented Software Production. Basic Assumptions. FAST Strategies. Foundations for Engineering Families. The Role of Abstractions in Identifying and Designing Families. The Role of Information Hiding and Separation of Concerns. Predicting Change. Organizational Considerations. 3. AN EXAMPLE: FAST Applied to Commands and Reports. The Commands and Reports Family. Defining the C&R Family. Using the C&R Application Engineering Environment. The SPEC Language and Its Translators. Designing the Translators. 4. An Overview of FAST. The Structure of FAST. The Economics of FAST. Case 1: No Domain Engineering. Case 2: Domain Engineering. The Fundamental Law of Family Production. Risk Versus Automation. Application Engineering. Application Engineering Artifacts. Application Production Activities. Domain Engineering. Domain Engineering Artifacts. Domain Engineering Activities. Organizational Roles. Variability in the FAST Process. 5. AN EXAMPLE: The Floating Weather Station Family. The Floating Weather Station Family. Qualify the FWS Domain. Engineer the FWS Domain. Analyze the FWS Domain. Implement the FWS Domain. Addendum A: The Floating Weather Station Commonality Analysis. Introduction. Overview. Dictionary of Terms. Commonalities. Variabilities. Parameters of Variation. Issues. Message Formats. Sensor Driver Identifiers. Addendum B: The Floating Weather Station Module Guide. Behavior-Hiding Modules. Device Interface Modules. Software-Design-Hiding Modules. Issues. Addendum C: The Floating Weather Station Application Generation Environment. Family Member Generator. Addendum D: A Generated Floating Weather Station Family Member. Addendum E: The Floating Weather Station Environment Simulator. 6. Process Modeling. Motivations for Process Modeling. A PASTA Model as a Communications Medium. Elements of a PASTA Model. Process Activities as State Machines. Artifacts as State Machines. Prescribing the Order of Events. Prescribing a Methodology. The Role of Process Modeling in FAST. PASTA Abstractions Creating PASTA Process Models. The Process User's Concerns. PASTA Models as Used by Process Environment Developers. Process Measurement Using PASTA. Measuring a Process Model. Measuring Process Performance. 7. Representing a PASTA Model. Representations of PASTA Elements. PASTA Forms. Notational Considerations. Artifact Definition Form. A-State Machine Diagrams. Process State Definition Form. P-State Machines. Relation Definition Form. Role Definition Form. Operation Definition Form. Analysis Definition Form. 8. An Overview of the FAST PASTA Model. FAST Model Hierarchies. FAST Artifacts. Environment Artifacts. Application Artifacts. Change_Report. FAST Activities. Qualify_Domain Engineer_Domain. Implement_Domain. Engineer_Application. Manage_Project. Change_Family. FAST Roles. FAST Manager. Gluing the Elements Together: The State Transition Diagrams. Typical Questions Answered by the Model. First Steps in Applying the Model. Identifying Starting Activities and Roles. Other Scenarios. 9. Artifact Definitions. Family_Artifact. Environment. Domain_Model. Domain_Implementation. Application. Application_Model. Application_Documentation. Application_Code. Change_Report. 10. Activity Definitions. FAST. Qualify_Domain. Gather_Data. Analyze_Data. Reject. Accept. Engineer_Domain. Analyze_Domain. Implement_Domain. Engineer_Application. Model Application. Produce_Application. Delivery_And_Operation_Support. Manage_Project. Change_Family. Request_Family_Change. Evaluate_Implementation_Change. Evaluate_Domain_Change. Library_Activities Review_Internally. Review. Iterate_Or_Refine. 11. Role Definitions. Project_Manager. Domain_Manager. 12. FAST Analyses. Application_Engineering_Process_To_Decision_Trace_Analysis. Application_Engineering_Process_To_Tool_Trace_Analysis. Application_Engineering_Support_Analysis. Application_Modeling_Language_Editor_Assurance_Analysis. Application_Modeling_Language_Parser_Assurance_Analysis. Application_Modeling_Language_To_Family_Design_Trace_Analysis. Artifact_Implementation_Assurance_Analysis. Commonality_To_Module_Trace_Analysis. Composition_Mapping_To_Family_Design. Composition_Mapping_To_Language_Construct_Mapping_Analysis. Composition_Mapping_To_Module_Trace_Analysis. Customer_Satisfaction. Decision_To_Tool_Trace_Analysis. Defect_Analysis. Final_Product_Documentation_Assurance_Analysis. Final_Product_Validation_Analysis. Module_Documentation_Assurance_Analysis. Module_Implementation_Assurance_Analysis. Parameter_Of_Variation_To_Decision_Trace_Analysis. Parameter_Of_Variation_To_Language_Trace_Analysis. Parameter_Of_Variation_To_Module_Trace_Analysis. Progress_Analysis. Resource_Analysis. Risk_Analysis. Terminology_Analysis. Tool_Documentation_Assurance_Analysis. Tool_Implementation_Assurance_Analysis. Variability_To_Variation_Parameter_Trace_Analysis. Variation_Parameter_To_Variability_Trace_Analysis. 13. FAST Relations. Application_Model_Module. Commonality_Module. Composition_Mapping_AML. Decision_Process. Decision_Tool. Module_Document. Module_Implement. Parameter_Decision. Parameter_Module. Product_Document. Tool_Document. Tool_Implement Variability_Parameter. Patterns of Thought and Work. FAST and Reuse. FAST as a Multiparadigm Process. FAST and Object Orientation. Applicability of FAST. Finding Domains Where FAST Is Worth Applying. The Single-Customer, Single-Product-Family Situation. The Many-Customers, Single-Product-Family Situation. The Many-Customers, Many-Product-Families Situation. Applying FAST Incrementally. Patterns of a FAST Organization. Applying PASTA. Transitioning to a FAST Process. Glossary. Bibliography. Index. 0201694387T04062001

The manifold ways of perception

Abstract: One of the great puzzles of visual perception is how an image that is in perpetual flux can still be seen by the observer as the same object. In an informative Perspective, Seung and Lee explain the mathematical intricacies of two new algorithms for modeling the variability of perceptual stimuli and other types of high-dimensional data (Tenenbaum et al., and Roweis and Saul).