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Determining the right requirements to develop a system is crucial as it involved variety of people and it affects the quality of the end product. Different stakeholders have different requirements which they may express in different ways. Naturally, they will express requirements in their own terms and with implicit knowledge of their own work. Generally, stakeholders are not sure of what they want from the computer system except in the most general terms. Hence, conflicts are inevitable. Negotiation is applied to resolve the conflicts and becoming popular nowadays to better improve requirements engineering process. Therefore, this paper is empirically confirming the effectiveness of negotiation effort in order to improve the level of agreement among all the stakeholders. Agreed requirements are believed to represent all the stakeholders' perspectives and perceptions and to obtain a set of unambiguous, correct, complete, consistent and achievable requirements. [ABSTRACT FROM AUTHOR]

Software systems need to evolve, and systems built using model driven approaches are no exception. The role of the models are increasing and becoming more and more important in the software development and evolution. So, the Model-Driven Software Evolution (MoDSE) is prominent. Several stakeholders are involved in the process of evolution. These user groups (stakeholders) have different concerns relevant to the models to be evolved in MoDSE. Multiple views provide a means to visualize complex information and are also a way to fulfill the concerns of different user groups. In this paper the concept of multiple views for the MoDSE is introduced and shows how these multiple views addresses the stakeholders concerns. The different viewpoints are identified to construct the multiple views. This paper also shows an analytical support how the proposed views are closer to the Lehman's laws of software evolution. [ABSTRACT FROM AUTHOR]

This paper focuses on an empirical layout improvement project. In the implementation process of the project, the authors followed an enhanced procedure to increase the involvement of the area experts in the layout design process, which assured the successful realisation of an appropriate layout solution satisfied to both the project team and the top management of a case company. In this paper, the project, the enhanced procedure and the designed new layout for a shop floor in the case company by applying the procedure are introduced, and the summarised evaluation on the new layout and the enhanced procedure is also presented. [ABSTRACT FROM AUTHOR]

TOKAI RIKA is a manufacturer using 3D data in their operations. The company's core business lies in the production of car parts. To enhance their in-house mold-making operations, the company decided to switch from paper to 3D data. The company proved very successful by using a unique method of coloring work specifications. They are using 3D to improve engineering communication in mold design. [ABSTRACT FROM AUTHOR]

The general thermodynamically based theory of the constitutive and evolution equations of elastic-brittle damaged materials in a total stress-strain formulation, developed by Murakami and Kamiya [162], is the key for a further extension presented in the paper by Kuna-Ciska l and Skrzypek [208]. The Helmholtz free energy is a function of the elastic strain tensor εe, the second-rank damage tensor D, and another scalar damage variable β. The following Helmholtz free energy decomposition into the elastic and the damage terms is postulated as the state potential (2.20): 3.1$$ \rho \Psi (\varepsilon ^e ,D,\beta ) = \rho \Psi ^e (\varepsilon ^e ,D) + \rho \Psi ^d (\beta ) $$ [ABSTRACT FROM AUTHOR]

An enormous amount of multimedia data will be transmitted by various devices in the wireless personal area network, and this network environment will require very high transmission capacity. In this paper, we apply multiple antennas to MB-OFDM UWB system for high performance. With an emphasis on a preamble design for multichannel separation, we address the channel estimation in MB-OFDM system with multiple antennas. By properly designing each preamble for multiple antennas to be orthogonal in the time domain, the channel estimation can be applied to the MB-OFDM proposal for IEEE 802.15.3a standard in the case of more than two transmit antennas. By using the multiantenna scheme and proposed channel estimation technique, the reliability and performance of the MB-OFDM system can be improved. [ABSTRACT FROM AUTHOR]

A combination of OFDM with FDMA (called OFDMA) is regarded as a promising solution for improving the performance of BWA with multiple users. Although transmit diversity is clearly advantageous in OFDMA systems, it may not be possible that practical OFDMA systems have more than two antennas due to size, cost, or hardware limitations. Cooperative networks aim to utilize the available terminals as a collection of distributed antennas for the transmission of signals from one end of the network to the other. This paper focuses on design and performance evaluation of IEEE 802.16 MIMO-OFDMA systems with cooperative diversity. In this chapter, for high-rate and reliable transmission, efficient transmission codes of cooperative transmission are proposed for each transmission case (single transmission case or mutual transmission case). [ABSTRACT FROM AUTHOR]

Radio frequency identification (RFID) technology is not fundamentally new and concerns a whole range of applications. The first RFID application may have been the Royal British Air Force's "Identify Friend or Foe" system, which was used during the Second World War to identify friendly aircraft. RFID can be applied to a variety of tasks, structures, work systems, and contexts along the value chain, including business-to-business (B-2-B) logistics, internal operations, business-toconsumer (B-2-C) marketing, and after-sales service applications [1-6]. However, the boom that RFID technology enjoys today is basically due to the standardization [7] and development of low cost devices. Like every wireless device, RFID systems bring with them security and privacy issues to all those people who have been working in this area. Security issues involve classic attacks, namely denial of service, impersonation of tags, or channel eavesdropping. These attacks are rendered more practicable because of the tags' lack of computational and storage capacity. There are many papers investigating these issues in various ways [7, 8, 10-12, 14]. Today's challenge is to find protocols (or deployments) which allow authorized parties to identify the tags without an adversary being able to track them, thus getting to the root of the privacy problem [8, 13]. It is well known that the reason not to use well known authentication protocols is that such protocols do not preserve the privacy of the provider. Asymmetric cryptography could easily solve this problem, but it is too heavy to be implemented within a tag. [ABSTRACT FROM AUTHOR]

Searching information on the Web can be viewed as extremely easy, or it can be extremely difficult. This is because the WWW is not indexed like many library catalogs or journal-article indexes. When we search on the Web, we are not searching it directly but are actually searching the Web pages collected and indexed by a search tool from computers all over the world that contains the actual Web pages. Examples of search tools are Yahoo! Search, Google, Alta Vista, and so on. The different types of search tools have their own strengths and weaknesses. Depending on your information needs, one may work better for you than another. Search directories are hierarchical databases with references to websites. The websites that are included are classified according to the rules of that particular search service. Search engines, on the other hand, use software to crawl the Internet in search of what you would like using of terms or keywords. Specialized databases are the hidden parts of the WWW that are normally not found by regular search engines [1]. This paper presents the extension work from Integrated Filtered Web-Search Engine (IFWSE) [2] by looking at the enhancement of the program structure to retrieve the search hits. Further experiments were also carried out to compare its performance with with a well-established, meta-search engine-the MetaCrawler [3] [4]. [ABSTRACT FROM AUTHOR]

The contributions, lessons, and trends found in the DESider Symposium Proceedings are discussed. Three broad classifications can be made among the papers: The first is between studies which widen the code- and user-base of DES and its range of applications to establish the current level of quality, and those which bring out neighbouring hybrid concepts such as SAS for discussions and improvements.The second is between "natural" uses of DES with boundary layers fully covered by RANS, and uses with RANS only as a wall model in LES.The third is between single-model methods such as DES, and zonal methods even if they are closely related. [ABSTRACT FROM AUTHOR]

Hybrid RANS/LES methods combine the advantages of RANS models in terms of simulation costs, with the ability of LES to capture unsteady flow structures. A problem encountered in applications of this technique is the transmission of information between the RANS and LES zones: in the RANS region only mean-flow data is available, and the Reynolds shear stresses are entirely supported by the turbulence model; in the LES region, on the other hand, turbulent eddies must be present to support the turbulent momentum transport. The generation of these eddies is a critical ingredient in determining the effectiveness and accuracy of a hybrid method. In this paper we discuss this problem for applications in which the RANS region is below the LES zone, and in cases in which the flow advects from RANS to LES regions. We will also present recent results from our research group. [ABSTRACT FROM AUTHOR]

The paper evaluates a new method for prescribing synthesized turbulent inlet boundary conditions. When making LES, DES or hybrid LES-RANS, a precursor channel DNS is often used. The disadvantage of this method is that it is difficult to re-scale the DNS fluctuations to higher Reynolds numbers. In the present work, synthesized isotropic turbulent fluctuations are generated at the inlet plane with a prescribed turbulent length scale and energy spectrum. A large number of independent realizations are generated. A correlation in time between these realizations is introduced via an asymmetric, non-truncated time filter. In this way the turbulent time scale of the synthesized isotropic turbulent fluctuations is prescribed. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the behaviour of DES-type methods used as Wall-Modelled-Large-Eddy-Simulation (WMLES) and to the treatment of the eddy viscosity in the framework of turbulent inlet conditions. A new method named Stimulated Detached Eddy Simulation (SDES) based on a synthetic turbulence method including pseudo-eddy viscosity synthetization is proposed and assessed on a spatially developing boundary layer. [ABSTRACT FROM AUTHOR]

The present paper summarizes the research conducted at the University of Manchester over the course of the Desider project on methods of generation of synthetic turbulence. A random procedure, referred to as the Synthetic Eddy Method (SEM), based on the classical view of turbulence as a superposition of coherent structures was developed and compared with other methods of generation of inflow boundary conditions for LES, for different types of wall bounded flows. Synthetic inflow generation methods always show a transition region downstream of the inlet until the turbulence recovers an equilibrium state. The sensitivity of this transition region to variations in the synthetic inflow turbulence energy, length scale and time scale is studied herein with applications to hybrid RANS-LES methods in mind, as RANS results cannot be expected to provide accurate values for these scales to the LES region. A parameterization of the SEM suitable for hybrid RANS-LES simulations is proposed and tested on hybrid RANS-LES simulations of several wall bounded flows, with an emphasis on the flat plat boundary layer. [ABSTRACT FROM AUTHOR]

This paper focuses on numerical aspects for hybrid RANS-LES computations using the X-LES method. In particular, the impact of using a high-order finite-volume scheme is considered. The finite-volume scheme is fourth-order accurate on non-uniform, curvilinear grids, has low numerical dispersion and dissipation, and is based on the skew-symmetric form of the compressible convection operator, which ensures that kinetic energy is conserved by convection. A limited grid convergence study is performed for the flow over a rounded bump in a square duct. The fourth-order results are shown to depend only mildly on the grid resolution. In contrast, second-order results require at least half the mesh size to become comparable to the fourth-order results. Additionally, the high-order method is extended with shock-capturing capability in such a way that interference with the subgrid-scale model is avoided. The suitability of this extension is demonstrated by means of a supersonic flow over a cavity. [ABSTRACT FROM AUTHOR]

This paper presents a first industrial attempt at Eurocopter Germany to use DES-like methods to compute the wake behind a helicopter in forward flight. Three codes have been used: TAU (DLR), CFX (Ansys) and HMB (Uni. Liverpool) and four different turbulence models: standard SST and three of its unsteady extensions SAS, DES and XLES. Results for the loads, pressure distribution and skin-friction lines have been compared to each other and against wind tunnel experimental data. These more sophisticated models brought improvements over the base SST but not always markedly and consistently: the drag gets improved although the negative lift on the body departs further form the experimental value. The pressure distribution on the backdoor has been improved by one of the computation. Oil-flow visualisation results show that the mean flow in the region of the backdoor is qualitatively reasonably well captured. [ABSTRACT FROM AUTHOR]

In this paper the three-dimensional non-reacting turbulent flow field of a swirl-stabilized gas turbine model combustor is analysed with compressible CFD. For the flow analysis URANS and Hybrid RANS/LES (DES, SAS) turbulence models were applied. The governing equations and the numerical method are described. The simulations were performed using the commercial CFD software package ANSYS CFX-10.0. The numerically achieved velocity components show a good agreement with the experimental values obtained by Particle Image Velocimetry (PIV). Furthermore, a precessing vortex core (PVC) could be found in the combustion chamber. [ABSTRACT FROM AUTHOR]

This paper presents a transonic buffet simulation on a half wing/body rigid model at a realistic Reynolds number. The modelling approach retained is a Zonal-DES approach which allows attached boundary layers to be protected and a rapid switching into LES mode in the separated areas. Transonic buffet phenomenon is a challenging case for DES type simulations since the separation point is unstable during time and the separation remains closed to the skin of the model. The simulation was performed on an adapted mesh and comparisons with experiments are carried out. It is shown that the mean field is accurately predicted with ZDES while the present RANS calculations failed to reproduce this shape of the separated area. The results also provide an insight into the unsteady nature of the flow. [ABSTRACT FROM AUTHOR]

The prediction of the laminar to turbulence transition is essential in the calculation of turbine blades, compressor blades or airfoils of airplanes since a non negligible part of the flow field is laminar or transitional. In this paper we compare the prediction capability of the Detached Eddy Simulation (DES) with the Large Eddy Simulation (LES) using the high-pass filtered (HPF) Smagorinsky model (Stolz et al., 2003) when applied to the calculation of transitional flows on turbine blades. Detailed measurements from (Canepa et al, 2003) of the well known VKI-turbine blade served to compare our results with the experiments. The calculations have been made on a fraction of the blade (10%) using non-reflective boundary conditions of Freund at the inlet and outlet plane extended to internal flows by (Magagnato et al., 2006) in combination with the Synthetic Eddy Method (SEM) proposed by (Jarrin et al., 2005). The SEM has also been extended by (Pritz et al., 2006) for compressible flows. It has been repeatedly shown that hybrid approaches can satisfactory predict flows of engineering relevance. In this work we wanted to investigate if they can also be used successfully in this difficult test case. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the DES methods implemented at the Institute of Fluid Mechanics and Engineering Acoustics (ISTA) at the TU-Berlin during the course of the European DESider project. As well as the validation of these methods on the basis of simplified, academic flow cases presented in the first part, their suitability and necessity for complex industrial applications is demonstrated using results from other research projects. The methods prove robust and reliable for a wide range of applications, ranging from external to internal flows, from bluff bodies with massive separation to the partial resolution of attached boundary layers. [ABSTRACT FROM AUTHOR]

Increasingly, design studies rely on numerical tools for more and more complex situations. Unfortunately, for some, if not many, of these complex cases, steady RANS has been unable to meet the challenge and cannot capture some of the most important features. At the same time, the continuing increase in computing power has made the use of unsteady simulations feasible, although not on a day-to-day basis, for a growing number of applications. The present paper reports on the experience of implementing one such unsteady technique known as Detached Eddy Simulation (DES) in a RANS-based industrial solver. [ABSTRACT FROM AUTHOR]

The present paper presents a simulation of supersonic inlet buzz on a 20x106 points mesh, using the DDES (Delayed Detached Eddy Simulation) method. This latter approach is a version of DES that ensures the attached boundary layers to be treated in RANS. The results are compared to experimental data obtained during a previous campaign of wind-tunnel experiments. The buzz experimentally observed at Mach 1.8 is well reproduced. The buzz frequency, as well as higher frequencies existing in the experimental pressure signals, are correctly predicted. The functions of DDES prove to be robust and to perform satisfactorily. [ABSTRACT FROM AUTHOR]

The paper reports on the current state of the SST-based Scale-Adaptive Simulation model (SST-SAS model), and summarises the validation activity performed with this model in the course of the DESIDER project. The turbulence-resolving capability of the SST-SAS model has been validated with the official project test cases, covering both the underlying generic flows as well as practical aerodynamic applications. Among the latter ones are also the two aero-acoustic test cases of industrial interest. The paper includes a brief description of the current state of the SST-SAS model, as well as the illustrating test case results. Potentials of the SAS approach are briefly discussed, as well as its position amongst the other transient simulation methods. [ABSTRACT FROM AUTHOR]

This paper provides a study of the dynamic stall of a pitching NACA 0012 airfoil at 106 Reynolds number by means of numerical simulation. A 2D study is carried out comparing three OES and URANS turbulence models (URANS, URANS k-ω SST and k-ε OES). Then a 3D computation is performed using DES Spalart modelling. URANS k-ω SST is providing the best results for 2D computations. [ABSTRACT FROM AUTHOR]

This paper reports the predictions of three turbulence modelling schemes in the application to the flow around a circular cylinder in a square duct. A URANS scheme known as the Stress-Strain Lag model has been developed in the DESider project, specifically to capture the effects of stress-strain misalignment observed in unsteady mean turbulent flows (Revell, 2006). Coupling of the Lag model with the popular k -ω SST model, to form the so-called SST-Cas model, has been shown to incorporate some of the advantages of a full Reynolds Stress transport Model (RSM), whilst retaining the efficiency and stability benefits of a eddy viscosity model (EVM) (Revell et al., 2006, 2007). This paper first presents 2-D results of the cylinder case, before examining the fully 3-D case, which is also calculated using the SST-DES approach. [ABSTRACT FROM AUTHOR]

In this paper, we proposed a new subgrid scale (SGS) model in large eddy simulation (LES) of a high Reynolds number turbulent flow. The traditional approaches are usually based on modeling of the non-resolved velocity field, and are customary invariant on the Reynolds number. When the Reynolds number is high, the flow at subgrid scales is intermittent and its structure is depending on the Reynolds number. To account for this, the new SGS model is focused on simulation of the non-resolved acceleration of fluid particle. With this model, an approximation of unfiltered velocity field is reconstructed by computation of the instantaneous model-equation introduced in the paper. The performed computation of a high Reynolds number stationary homogeneous turbulence reproduced qualitatively the effects of intermittency recently observed in experimental studies. [ABSTRACT FROM AUTHOR]

Applications using rf radios operating at frequencies above 1 GHz are proliferating. The highest operating frequencies continue to increase and applications above 10 GHz and up to 77 GHz are already emerging. Systems become more complex and devices need to operate at several different frequency bands using different wireless standards. The rf-front end sections of these devices are characterized by a high diversity of components, in particular high precision passive components. In order to be produced cost-effectively, these elements need to be integrated along with the semiconductor devices. This paper describes the requirements for successful integration of rf-passive devices and proposes multilayer thin film technology as an effective rf-integration technology. [ABSTRACT FROM AUTHOR]

In automotive power applications protection and diagnosis is getting more and more important. Main reasons for this trend are safety requirements, high reliability and complex power management of modules in a car. This paper describes aspects and challenges of designing smart power high-side switches embedded in automotive systems to drive inductive, capacitive and resistive loads. [ABSTRACT FROM AUTHOR]

In this paper we will explain the trends in short-range broadband communication and investigate the technology requirements necessary for implementing the PA building block. Further we will discuss the importance of the power grid on the stability of the PA. Finally a single-ended integrated PA, part of a WiMedia/MBOA compliant UWB transceiver, is presented. [ABSTRACT FROM AUTHOR]

This paper gives an overview of several design issues for CMOS Power Amplifiers (PA) for wireless and mobile communications. The challenges, faced by the RF PA designer, and the different trade-offs, encountered during the design process, are clearly indicated. The idea of power combining is introduced and it is clarified how this technique can alleviate some of the problems related to the aggressive CMOS scaling. The theory is clarified by several design examples that cover a frequency range from the lower GHz as high as 60 GHz. [ABSTRACT FROM AUTHOR]

This paper presents a power-efficient high-speed serial interface solution, which is targeted for use in battery-operated mobile or handheld devices. Both transceiver topology and signaling protocol are described. High-speed differential and CMOS signaling are merged on the same wires. The signaling scheme contains link power management features and provides multiple communication modes to adapt efficiently to bandwidth needs. This interface has been implemented in 65nm CMOS and measurement results are shown. [ABSTRACT FROM AUTHOR]

New and improved xDSL standards are developed to bridge the last mile between the Central Office (CO) and the end user. The aDSL2+ standard doubles the bandwidth of a basic aDSL system to 2.2MHz and hence increases the bitrate up to 24Mb/s. The high Crest Factor (CF) of Discrete Multi Tone (DMT) modulated signals, however, poses serious problems on an efficient and low cost implementation of the line driver in the CO [1]. With the emerging nanometer technologies the line driver remains more than ever the bottleneck for lowering the cost and power. The low supply voltages originating from nanometer technologies increase the current density in the line driver, which affects its efficiency and reliability. This paper presents a high voltage high efficient aDSL2+ CO line driver in a mainstream nanometer CMOS technology. [ABSTRACT FROM AUTHOR]

The large scale deployment of the voice over IP, or voice over packet technology and the migration of this technology towards the edge of the network stimulates a revival of SLIC and CODEC design. The basics of this existing technology are refreshed and the architecture of a specific implementation is described in this paper. New smart power technologies with single chip low voltage CMOS and high voltage DMOS and bipolar devices allow for full single chip SLIC & CODEC integration. Another option is to put the low voltage CODEC in a deep sub micron system on chip with a mini-SLIC, integrating only the high voltage drivers. In the field new voice circuits get deployed now to bring voice to the phone over the wideband network and do the conversion from wideband IP coded voice to the analogue real world speech signals as close to the phone as possible via an Analogue Telephone Adaptor [ATA]. The conversion can be done in the phone as a real IP-phone, in a PC (Skype) via the audio of the PC or via an ATA, driving a regular phone. The conversion can also be done in the house via a VoIP to POTS converter next to the wideband modem, in your garage e.g. to drive your existing home phone cabling. The conversion can also be done with an ATA in the street cabinets driving only the last kilometer to your home phone. In this paper a Short Haul Line Integrated Circuit [SHLIC] is described, used to transmit Voice over Internet Protocol, also called VoIP, IP Telephony, Internet telephony, wideband telephony, wideband phone, and the routing of voice conversations over the Internet or through any other IP-based network. The SHLIC is a pure analogue circuit processed in a high voltage technology. Also the CODEC, performing the wideband 16Ksamples/s or A/µ law narrow band signal processing, is briefly described. [ABSTRACT FROM AUTHOR]

This paper discusses very high frequency radio links from the application level down to the circuit constraints. Because of the technical difficulties and higher cost of technologies and packaging, applications at these frequencies only make sense when the special properties of these high frequencies are offering clear advantages for these applications. Such advantages can be higher system capacity, better security and privacy, or higher spatial resolution. Exploiting these advantages requires careful choices in system design and architecture, and imposes specific constraints on circuits and technologies. In most cases, it will also require beam forming through phased array antenna structures. Implementation of the signal processing for beam forming can be achieved in an efficient way in the RF domain. [ABSTRACT FROM AUTHOR]

This paper examines the suitability of advanced SiGe BiCMOS and sub 65nm CMOS technologies for applications beyond 80GHz. System architectures are discussed along with the detailed comparison of VCOs, LNAs, PAs and static frequency dividers fabricated in CMOS and SiGe BiCMOS, as required for automotive cruise-control radar, high data-rate radio, and active and passive imaging in the 80GHz to 160GHz range. It is demonstrated experimentally that prototype SiGe HBT and BiCMOS technologies have adequate performance for all critical 80GHz building blocks, even at temperatures as high as 125 C. Although showing promise, existing 90nm GP CMOS and 65nm LP CMOS circuits at these frequencies remain significantly inferior to their SiGe counterparts. [ABSTRACT FROM AUTHOR]

Implicit in the design of a 60GHz receiver front-end is the re- quirement for broadband amplification and gain flatness in order to support advanced modulation schemes. As we have seen from lower frequency wireless systems, the choice of technology often dictates the system architecture. While either silicon CMOS or silicon Bipolar technology could be used for implementation, cost, availability, performance and time to market constraints typically dictate the technology choice. The trade-offs between CMOS and Bipolar/BiCMOS technologies for mm-wave receiver circuits are outlined in this paper. Realizing low-noise performance and gain flatness over a wide bandwidth is used as a case study from both the circuit and system points of view. [ABSTRACT FROM AUTHOR]

Summary. The problem studied here is a shortest path problem of the type encountered in sub-Riemannian geometry. It is distinguished by special structures related to its Lie group setting and the Z2 graded structure on the relevant Lie algebra. In spite of the fact that the first order necessary conditions lead to differential equations that are integrable in terms of elementary functions, in this case there remain questions related to the existence of appropriate values for the parameters which appear. In this paper we treat the problem in some generality but establish the existence of suitable parameter values only in the case of the general linear group of dimension two. [ABSTRACT FROM AUTHOR]

Summary. This paper gives a comparison principle for first-order PDEs of the Hamilton-Jacobi-Bellman type that arise in problems of nonlinear target control synthesis and reachability analysis under hard bounds on the controls. The emphasis is is on treating backward reachability sets for a system with moving target sets which may also turn to be forward reachability tubes of another system. The target sets are to be reached within preassigned intervals. The exact solutions to this problem, given in set-theoretic terms, are expressed as level sets to the solutions of some specific types of the HJB equation. But these solutions require fairly complicated calculation. The present paper presents an alternative approach that avoids exact solutions in favor of their upper and lower bounds, which in many cases may suffice for solving the required problems. For systems with linear structure ellipsoidal estimates are given, which ensure accurate approximations of nonconvex reachability sets through unions of ellipsoids. [ABSTRACT FROM AUTHOR]

Summary. During the last decade, pseudospectral (PS) optimal control methods have emerged as demonstrable efficient methods for computational nonlinear optimal control. Some fundamental problems on the feasibility and convergence of the Legendre PS method are addressed. In the first part of this paper, we summarize the main results published separately in a series of papers on these topics. Then, a new result on the feasibility and convergence is proved. Different from existing results in the literature, in this new theorem neither the invertibility of necessary conditions nor the existence of limit points is assumed. [ABSTRACT FROM AUTHOR]

Summary. In spite of the success of traditional sampled-data theory in computer control it has some disadvantages particularly for distributed, asynchronous, and multi-rate system. Event based sampling is an alternative which is explored in this paper. A simple example illustrates the differences between periodic and event based sampling. The architecture of a general structure for event based control is presented. The key elements are an event detector, an observer, and a control signal generator, which can be regarded as a generalized data-hold. Relations to nonlinear systems are discussed. Design of an event based controller is illustrated for a simple model of a micro-mechanical accelerometer. [ABSTRACT FROM AUTHOR]

Summary. We present results on omega-limit sets and minimum phase zero dynamics for hybrid dynamical systems. Moreover, we give pointers to how these results may be useful in the future for solving the output regulation problem for hybrid systems. We highlight the main attributes of omega-limit sets and we show, under mild conditions, that they are asymptotically stable. We define a minimum phase notion in terms of omega-limit sets and establish an equivalent Lyapunov characterization. Then we study the feedback stabilization problem for a class of minimum phase, relative degree one hybrid systems. Finally, we discuss output regulation for this class of hybrid systems. We illustrate the concepts with examples throughout the paper. [ABSTRACT FROM AUTHOR]

Summary. This paper is focused on the problem of output regulation for nonlinear systems within the main framework developed in [23]. The main goal is to complement that theory with some new results showing how the dimension of the internal model-based regulator can be reduced by preserving the so-called internal model property. It is shown how the problem of reducing the regulator dimension can be approached by identifying "observability" parts of the so-called steady-state input generator system. A local analysis based on canonical geometric tools and local observability decomposition is also presented to identify lower bounds on the regulator dimension. Possible benefits in designing redundant internal models are also discussed. [ABSTRACT FROM AUTHOR]

Summary. In extending the solvability of the output regulation problem to encompass more general classes of time-varying exogenous systems, various non-equivalent definitions of observability play a crucial role in the definition and properties of immersion mappings establishing the so-called "internal model property." This paper proposes a classification of the immersion mappings based on the underlying observability property, and describes the connections between different canonical realizations of internal models that fully exploit such properties for robust and adaptive output regulation design in periodic systems. [ABSTRACT FROM AUTHOR]

Summary. This paper presents a feedback method to achieve synchronization of coupled identical oscillators which are characterized by polynomial vector fields. Here, synchronization means asymptotic coincidence of the states of all the systems. Even though their models are identical, the state trajectories of the identical systems are different because of different initial conditions. Unlike other approaches where just a linear damping term is added to each system in order to achieve synchronization, we design nonlinear coupling functions between the subsystems in such a way that stability of the error dynamics between any two models results. To do that, a certain dissipation inequality and sum of squares as a computational tool are used. Finally, two examples are presented to illustrate the proposed method. [ABSTRACT FROM AUTHOR]

Summary. Up to what extent is it possible to simplify the nonlinearities of a given discrete-time system through transformations involving feedbacks or outputinjections? Solutions to these problems, at the basis of several control and state estimation design procedures, take advantage of a combined use of geometric and algebraic methods, two major setups in nonlinear control theory strongly influenced by the fundamental work of Alberto Isidori. Links between these frameworks are illustrated in the present paper which is written to celebrate his 65th birthday. [ABSTRACT FROM AUTHOR]

Summary. The paper deals with dynamic feedback linearization of multi input continuous time affine systems. The geometric properties of a dynamic feedback linearizable system as well as those of the compensator which achieves linearization are here enlightened. On the basis of these geometric properties an algorithm for the computation of a dynamic feedback obtained from the composition of regular static state feedback laws and integrators is proposed. Our result is based on the geometric approach introduced by Isidori and coworkers in 1981 for dealing with nonlinear control problems. [ABSTRACT FROM AUTHOR]

Summary. In this paper, we study the existence of periodic solutions to periodically forced systems in both the equilibrium and the nonequilibrium cases. In the equilibrium case, we prove an averaging theorem. Then, we develop the rigorous theory of the steady-state response of a nonlinear control system in order to derive some positive results on periodic forcing of autonomous systems with global Lyapunov attractors. Finally, on this occasion it is so much of a pleasure to thank Alberto Isidori for all he taught us and for all the joy we shared, and continue to share, in our research. Tanti auguri! [ABSTRACT FROM AUTHOR]

Summary. The problem of global state regulation by output feedback is investigated for a family of uncertain nonlinear systems that are bounded by a triangular system with unknown parameters. The bounding system is allowed to depend linearly on the unmeasurable states but nonlinearly on the systems output. Using the idea of universal control, together with the recent advance in nonlinear output feedback design, we develop a non-identifier based output feedback control scheme achieving, in the presence of nonlinear parameterization, global asymptotic state regulation as well as boundedness of the closed-loop system. The main contribution of the paper is two-fold: 1) the polynomial growth condition imposed in the previous work [6] is removed in this work; 2) an extension to uncertain cascade systems with zero-dynamics is carried out under mild structural and ISS conditions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to give a brief overall account of the present situation and outlook in terms of transport energy use and GHG emissions in the context of European Union transport policy. This topic is a huge one, and no attempt at comprehension is claimed. Instead the assessment will be based on a selection of a few key indicators, which the author believes are important to evaluate the present situation and identify challenges for future action and research. The indicators are all drawn from official sources or scholarly studies, while the ways in which they are interpreted and presented here are those of the author alone. During 2006 the European transport policy White Paper will undergo an official mid-term review by the European Commission. This will provide an opportunity for further reflections and possibly new directions for some of the issues to be discussed here. The present paper will first (in Section 10.2) present what we call system indicators, with the aim to highlight some critical aspects of the European transport systems' standing in terms of volume, growth, energy use and GHG emissions. Then the paper moves into policy. Section 10.3 highlights a few fundamental conditions for transport policy-making in the European Union, while Section 10.4 will go through some of the relevant targets and measures that have been adopted, evaluating them one by one with simple policy indicators. After summing up performance, Section 10.5 will address the outlooks for European transport beyond the present Kyoto agreement period, and some research issues related to policy implementation in that context will be identified. Finally a few conclusive statements are proposed, not about how much European transport, exactly, there will be room for in the common greenhouse of the future, but rather on the kinds of discussions that need to be faced in dealing with this sector's climate impact in the coming years. [ABSTRACT FROM AUTHOR]

The voluntary agreement between the European Commission and the automotive industry to cut new car CO2 emissions by 25% between 1995 and 2009 is probably the most important EU initiative to curb carbon emissions as it addresses the road transport sector, whose growth may cancel out all other attempts to meet the EU's Kyoto commitment. The paper evaluates progress in automobile fuel economy and CO2 emissions observed since 1995, examines the issue within the international context and attempts to assess whether further improvements are possible after 2010 in Europe. Based on data available up to mid-2005 it seems that, in the absence of strong technical progress and remarkable changes in consumer behavior until 2009, the industry's commitment can only be met with some years' delay. Moreover, it is most likely that technical progress will not persist in the future unless a policy mix of regulations and economic instruments is implemented. [ABSTRACT FROM AUTHOR]