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The post-yield hardening (PYH) behaviour is an important character of FRP confined concrete which has been studied by researchers worldwide for decades. In the phenomenon-based level, the authors propose a 3D geometrical method to interpret the mechanisms of analysis-oriented models. This method unifies most existing analysis- and design-oriented models. For the mechanism-based study, the physical behaviour of the FRP confined concrete is revealed by X-ray computed tomography (CT), and the initiation and propagation of the internal cracks are captured by the scanned images. Further, path dependency of FRP confined high-strength concrete (HSC) and nonlinear biaxial behaviour of FRP tube are modelled using the 3D geometrical method. Finally, this paper provides an introduction to the recent development of composite structural elements from the authors’ research group, which can maximize the confining efficiency and can improve the structural performance significantly.

There are currently limited data on how prosthetic devices are used to support lower-limb prosthesis users in their free-living environment. Possessing the ability to monitor a patient’s physical behaviour while using these devices would enhance our understanding of the impact of different prosthetic products. The current approaches for monitoring human physical behaviour use a single thigh or wrist-worn accelerometer, but in a lower-limb amputee population, we have the unique opportunity to embed a device within the prosthesis, eliminating compliance issues. This study aimed to develop a model capable of accurately classifying postures (sitting, standing, stepping, and lying) by using data from a single shank-worn accelerometer. Free-living posture data were collected from 14 anatomically intact participants and one amputee over three days. A thigh worn activity monitor collected labelled posture data, while a shank worn accelerometer collected 3-axis acceleration data. Postures and the corresponding shank accelerations were extracted in window lengths of 5–180 s and used to train several machine learning classifiers which were assessed by using stratified cross-validation. A random forest classifier with a 15 s window length provided the highest classification accuracy of 93% weighted average F-score and between 88 and 98% classification accuracy across all four posture classes, which is the best performance achieved to date with a shank-worn device. The results of this study show that data from a single shank-worn accelerometer with a machine learning classification model can be used to accurately identify postures that make up an individual’s daily physical behaviour. This opens up the possibility of embedding an accelerometer-based activity monitor into the shank component of a prosthesis to capture physical behaviour information in both above and below-knee amputees. The models and software used in this study have been made open source in order to overcome the current restrictions of applying activity monitoring methods to lower-limb prosthesis users.

The legs and transmissions of walking robots need to fulfill dynamic and load-bearing movements while also enabling more applications by being resistant to challenging outdoor- and aquatic environments. Furthermore, the physical behaviour of the robot legs needs to be predictable throughout their service life to enable torque-dependent control. Therefore, weathering and wear of leg components must not alter the movement resistance in order to avoid frequent maintenance. Hence, we present a new leg design that obtains low inertia and fluid resistance by using four-bar linkages with compliant mechanisms of either stainless spring steel or super-elastic nickel-titanium. The leg mechanisms were tested to formulise their torque behaviour, axial deflections, and fatigue life in saltwater (\(\approx \)12% salinity). Conventional sealed stainless steel ball bearings were also tested to provide data references. Our experiments show that nickel-titanium outperform stainless spring steel with more predictable behaviour, less resistance, and longer fatigue life.

When designing complex engineering machines, such as an aero-engine, there are many factors that need to be kept in consideration. However in essence they boil down to two important elements: Safety and operational efficiency. Essential though these two factors are, they are also at odds with each other in terms of their demands on eventual designs. The need for operational efficiency drives engineering solution towards ever-so lighter structures with optimised complex designs often requiring the utilisation of novel materials. All important safety on the other hand requires that a deeper understanding of underlying physical behaviour is acquired to ensure that the mechanical integrity is never at risk. The job of engineers operating in this field is to make sure that they utilise all available tools to map the solution space for an optimal balance of these two conflicting demands.

Corrosion of the reinforcement in concrete structures affects their structural capacity. This problem affects many existing concrete bridges and climate change is expected to worsen the situation in future. At the same time, assessment engineers lack simple and reliable calculation methods for assessing the structural capacity of structures damaged by corrosion. This paper further develops an existing model for assessing the anchorage capacity of corroded reinforcement. The new version is based on the local bond stress-slip relationships from fib Model Code 2010 and has been modified to account for corrosion. The model is verified against a database containing the results from nearly 500 bond tests and by comparison with an empirical model from the literature. The results show that the inherent scatter among bond tests is large, even within groups of similar confinement and corrosion level. Nevertheless, the assessment model that has been developed can represent the degradation of anchorage capacity due to corrosion reasonably well. This new development of the model is shown to represent the experimental data better than the previous version; it yields similar results to an empirical model in the literature. In contrast to many empirical models, the model developed here represents physical behaviour and shows the full local bond stress-slip relationship. Using this assessment model will increase the ability of professional engineers to estimate the anchorage capacity of corroded concrete structures.

People have erected buildings with the use of timber structures for a long time. The uses of timber constructions are very diverse—it is used for the production of exterior wall and roof constructions, window frames and doors, and it is used for dry as well as wet premises. Scandinavian countries have extremely vast experience of using timber structures. Latvia has a rather extensive timber processing and timber structure manufacturing sector. Many companies are involved in timber processing, however, to enable even more extensive use of timber structures, environmental and technically economic requirements of contemporary building must be taken into consideration. Environmental requirements for timber structures provide certain advantages in comparison to other building materials, but technically economic requirements are very important as well. The development of manufacturing of glued constructions and research of production processes of these constructions allows one to find solutions for the reduction in the cost of timber structures, and the results of such research can ensure significant development of the use of timber structures in building, as well as reduce total construction costs. The basic objective of the study is to investigate the residual materials arising as a result of processing cross-laminated timber constructions (CLT panels), material generated as a result of high levels of construction production, and research of the opportunities to reprocess the residual materials generated as a result of laminated timber structure manufacturing into materials suitable for production of building constructions. The majority of CLT panels are manufactured using 20, 30 and 40 mm thick boards, and, during the panel manufacturing process, there are various standard thicknesses of panels, for example, 60, 80, 100, 120, 140, 160 mm, etc. Various layers are used for the creation of various thicknesses depending on the necessary technical properties. Various arrangements of the thickness of a single panel will cause different structural and physical behaviour (i.e., impact of changes in moisture, fire resistance, etc.). During the research and for the purposes of testing of CLT panels, only residues with equal types and thicknesses of lamellae were selected. Two main purposes were included in the panel testing process: (1) Comparison of technical performance of the residues of CLT panels with the classic CLT panel. Curve strength and tensile strength tests were performed in accordance with LVS EN standards (LVS EN 16351: 2016 and LVS EN 408 + A1: 2012). All the samples were prepared according to the LVS EN standards. (2) To assess the impact of two resins (melamine urea formaldehyde (MUF) and polyurethane (PU)), widely used in industry, on structural properties of recycled CLT material. Results of the research show that recycling residues of glued wooden constructions may lead to good results, and manufacturing residues of CLT panels may be successfully used in construction and for the reduction in CLT panel manufacturing costs.

Recent technological advances have enabled the continuous and unobtrusive monitoring of human behaviour. However, most of the existing studies focus on detecting human behaviour under the limitation of one behavioural aspect, such as physical behaviour and not addressing human behaviour in a broad sense. For this reason, we propose a novel framework that will serve as the principal generator of knowledge on the user’s behaviour. The proposed framework moves beyond the current trends in automatic behaviour analysis by detecting and inferring human behaviour automatically, based on multimodal sensor data. In particular, the framework analyses human behaviour in a holistic approach, focusing on different behavioural aspects at the same time; namely physical, social, emotional and cognitive behaviour. Furthermore, the suggested framework investigates user’s behaviour over different periods, introducing the concept of short-term and long-term behaviours and how these change over time.

The 3MI instrument is a multi-directional spectro-polarimeter to fly on-board the Metop-SG platform to be launched in 2022, as part of EUMETSAT’s EPS-SG system space segment. As for most of radiometers devoted to Earth Observing from space, the radiometric budget is a system budget which includes many contributors, from the raw detector signal-to-noise to the artefact introduced by the ground correction in level-1 processing. The straylight happening in the optics is one of these contributors which could sometimes become dominant in the system budget. In this context, it is required to constrain the instrumental design as well as the ground characterization and its correction by processing. This is supported by maintaining accurate understanding of the straylight and its behaviour from early on in the project in order to check its radiometric level and quantify the potential impact on the products. This paper will present the analysis done to understand and model the physical behaviour of 3MI’s straylight. Based on initial inputs from the instrument builders and assuming some simplification, a physical straylight model was derived. This model allows an easy implementation in a simulator able to add this straylight contribution to any type of images, particularly on very realistic scenes. Our physical model shows advantageous complementarity to the builder’s simulations in the sense it allows a better quantification on a wide variety of realistic images while specifications usually assume theoretical targets such as a knife-edge transition. Such a capability is needed for 3MI system activities, in particular to cope with any deviation to the performance requirements. This paper presents examples of 3MI straylight-impacted images simulated at EUMETSAT using as input 1/ a simulation of the straylight provided by the instrument builder (ESA and Leonardo), and 2/ a realistic test data set based on PARASOL and MODIS acquisitions from the A-train observatory generated by ICARE/LOA. This simulator will be used during the development of the 3MI instrument and its ground characterization in order to monitor the impact on products.

In earthquake-prone zones of the world, severe damage to buildings and life endangering harm to people pose a major risk when severe earthquakes happen. In recent decades, active and passive measures to prevent building damage have been designed and deployed. A simple model of an active damage prevention system, founded on earlier work, is investigated from a model based formal development perspective, using Hybrid Event-B. The non-trivial physical behaviour in the model is readily captured within the formalism. However, when the usual approximation and discretization techniques from engineering and applied mathematics are used, the rather brittle refinement techniques used in model based formal development start to break down. Despite this, the model developed stands up well when compared via simulation with a standard approach. The requirements of a richer formal development framework, better able to cope with applications exhibiting non-trivial physical elements are discussed.

The treatment of cold-formed steel sections in design codes is very largely restricted to individual members under ideal conditions. More efficient design is possible if the complexities of the structural response caused by the thin plating and complex shapes, together with the actual conditions of load introduction and restraint arising from practical situations can be recognised. Traditionally this has only been possible by resorting to full-scale testing. This is, of course, time consuming and expensive; moreover, the impossibility of covering all variations of all the important problem parameters means that developing a comprehensive understanding of all aspects of the physical behaviour is unlikely. Numerical analysis offers the promise of an alternative approach. However, for this to be reliable there must be confidence that it accurately models the physical situation. For the past decade a programme of research has been underway aimed at the provision of a more complete understanding of the structural behaviour of cold-formed steel sections when employed in particular practical situations. Three such cases are addressed herein: purlins as used in the roofs of industrial buildings, beams used to support floors and columns forming part of a stud wall framing system. In each case the process has been to firstly identify all the important structural components including fastening arrangements, then to develop numerical models using ABAQUS that represent each of these physical features to a sufficient degree of accuracy, then to validate the models by comparison with all available test data, then to conduct parametric studies covering the full range of variables found in practice and, finally, to use the pool of results and the improved insights into behaviour as the basis for improved design approaches that, by more accurately capturing the key physical features, provide better predictions of performance. An important feature of this has been to ensure that the resulting design procedures were the simplest possible consistent with reliable predictions.

Shape memory is the capability of a material to be deformed and fixed into a temporary shape. Recovery of the original shape can then be triggered only by an external stimulus. Shape-memory polymers are highly deformable materials that can be programmed to recover a memorized shape in response to a variety of environmental and spatially localized stimuli as a one-way effect. The shape-memory function can also be generated as a reversible effect enabling actuation behaviour through macroscale deformation and processing, specifically by dictating the macromolecular orientation of actuation units and of the skeleton structure of geometry-determining units in the polymers. Shape-memory polymers can be programmed and reprogrammed into arbitrary shapes. Both recovery and actuation behaviour are reprogrammable. In this Review, we outline the common basis and key differences between the two shape-memory behaviours of polymers in terms of mechanism, fabrication schemes and characterization methods. We discuss which combination of macromolecular architecture and macroscale processing is necessary for coordinated, decentralized and responsive physical behaviour. The extraction of relevant thermomechanical information is described, and design criteria are shown for microscale and macroscale morphologies to gain high levels of recovered or actuation strains as well as on-demand 2D-to-3D shape transformations. Finally, real-world applications and key future challenges are highlighted. Shape-memory materials can generate programmable movements triggered by an external stimulus, such as an environmental change. In this Review, the authors discuss mechanisms, fabrication schemes, characterization methods and applications of the one-way shape-memory effect enabling shape recovery and of reversible shape-memory effects exhibiting actuation behaviour.

A case study centred on a fuel supply system for a small aircraft is presented in Hybrid Event-B, an extension of conventional Event-B that allows for the modelling and verification of hybrid and cyberphysical systems exhibiting nontrivial continuous behaviour. In contrast to many such case studies, which concentrate predominantly on timing issues, the focus in the present work is on nontrivial physical behaviour, and on the effect that this has on various refinement and partition strategies. More liberal proof obligations are developed to add flexibility to the decomposition process.

Numerical simulations of nanophotonics systems provide insight into their physical behaviour and design that provide a critical complement to experimental investigations. The finite-difference time-domain (FDTD) method is the most widely used, with its success due to its relative simplicity coupled with its broad applicability to many complex material systems, arbitrary shape configurations, time-domain visualization and, with increased computing resources, its near linear scalability for parallel computing.

There are two ways to turn a categorical model for pure quantum theory into one for mixed quantum theory, both resulting in a category of completely positive maps. One has quantum systems as objects, whereas the other also allows classical systems on an equal footing. The former has been axiomatized using environment structures. We extend this axiomatization to the latter by introducing decoherence structures., Comment: In Proceedings QPL 2015, arXiv:1511.01181

In this work we present a convolutional neural network-based (CNN) model that predicts future movements of a ball given a series of images depicting the ball and its environment. For training and evaluation, we use artificially generated images sequences. Two scenarios are analyzed: Prediction in a simple table tennis environment and a more challenging squash environment. Classical 2D convolution layers are compared with 3D convolution layers that extract the motion information of the ball from contiguous frames. Moreover, we investigate whether networks with stereo visual input perform better than those with monocular vision only. Our experiments suggest that CNNs can indeed predict physical behaviour with small error rates on unseen data but the performance drops for very complex underlying movements.

In the effort to develop critical cyberphysical systems, existing computing formalisms are extended to include continuous behaviour. This may happen in a way that neglects elements necessary for correct continuous properties and correct physical properties. A simple language is taken to illustrate this. Issues and risks latent in this kind of approach are identified and discussed under the umbrella of ‘healthiness conditions’. Modifications to the language in the light of the conditions discussed are described. An example air conditioning system is used to illustrate the concepts presented, and is developed both in the original language and in the modified version.

An outstanding problem in biogeochemical modelling of the ocean is that many of the key processes occur intermittently at small scales, such as the sub-mesoscale, that are not well represented in global ocean models. This is partly due to their failure to resolve sub-mesoscale phenomena, which play a significant role in vertical nutrient supply. Simply increasing the resolution of the models may be an inefficient computational solution to this problem. An approach based on recent advances in adaptive mesh computational techniques may offer an alternative. Here the first steps in such an approach are described, using the example of a simple vertical column (quasi-1-D) ocean biogeochemical model. We present a novel method of simulating ocean biogeochemical behaviour on a vertically adaptive computational mesh, where the mesh changes in response to the biogeochemical and physical state of the system throughout the simulation. We show that the model reproduces the general physical and biological behaviour at three ocean stations (India, Papa and Bermuda) as compared to a high-resolution fixed mesh simulation and to observations. The use of an adaptive mesh does not increase the computational error, but reduces the number of mesh elements by a factor of 2–3. Unlike previous work the adaptivity metric used is flexible and we show that capturing the physical behaviour of the model is paramount to achieving a reasonable solution. Adding biological quantities to the adaptivity metric further refines the solution. We then show the potential of this method in two case studies where we change the adaptivity metric used to determine the varying mesh sizes in order to capture the dynamics of chlorophyll at Bermuda and sinking detritus at Papa. We therefore demonstrate that adaptive meshes may provide a suitable numerical technique for simulating seasonal or transient biogeochemical behaviour at high vertical resolution whilst minimising the number of elements in the mesh. More work is required to move this to fully 3-D simulations.

A case study centred on a fuel supply system for a small aircraft is presented in Hybrid Event-B, an extension of conventional Event-B that allows for the modelling and verification of hybrid and cyberphysical systems exhibiting nontrivial continuous behaviour. In contrast to many such case studies, which concentrate predominantly on timing issues, the focus in the present work is on nontrivial physical behaviour, and on the effect that this has on various refinement and partition strategies.

Reference EPFL-ARTICLE-218074doi:10.1155/2016/6745760View record in Web of Science Record created on 2016-04-17, modified on 2016-08-09

Virtual and augmented reality have been used in the performing arts with two main purposes in mind: the design of artificial sceneries and the augmentation of the actor's performance. We are mostly interested in the second application that offers new perspectives for the interaction between actors and digital media. This article describes the design of a new interface for the definition and control of multi-layer interactive 2½D scenes by performers. The resulting virtual and animated environment is a stack of semi-transparent layers associated with physical models. Because of their intuitive physical behaviour and their capacity to be adapted to various geometries, these virtual props are well suited for the stage and their manipulation by performers. The interface used to design and control these objects extends the classical layer/mask paradigm to interactive spatialised scenes made of surfaces controlled by physical models such as mass-spring systems. This work is the result of a collaboration...

SUMMARY This paper provides an overview of progress in selected topics related to the modelling and simulation of high-frequency electronic circuits. There are several specific features of this regime that distinguish it from more conventional electronic analysis; however, here we will just emphasize two: firstly, the durable value, and yet the intrinsic limitations, of the circuit paradigm in representing the physical behaviour of highfrequency electronic devices, and secondly, the challenge of efficiently representing frequency-domain linear data in general non-linear transient simulation. Copyright q 2007 John Wiley & Sons, Ltd.

Sensory properties of product are the most vital attributes, as they are most apparent to consumers. New era required new methods and tools to understand both the product and consumers. Objective measurements are more rapid, reliable and repeatable, but subjective also cannot be ignored. Subjective sensory analysis can be correlated with objective analysis. Different statistical tools and mathematical modelling is useful to correlate the instrument measurement with panel measurements. Subjective measurement can also be modulated by use of different psychophysical model and understanding of fundamental physical behaviour of food in mouth. Objective measurement is standardized by the subjective measurements, as only consumer perceive which is acceptable or not, and the acceptable value can be given as standard for objective measurements in routine testing. Further research to develop more inter relationship between these two is needed.

Various aspects of chemical instrument miniaturizing are explored. The limitations imposed by scaling laws are discussed, and the influences of system dynamics on chemical and physical behaviour of molecules in microsystems are presented. The complexity of chemical systems, as defined by intra- and intermolecular forces, influencing minimum device dimensions is illustrated for solution and gas-phase species. The basic concepts for environmental sensor networks are presented for a hypothetical system.

According to the ISO Geometrical Product Specifications (GPS), the establishment and definition of common datum for geometrical components are not fully defined. There are two main limitations of this standard. Firstly: the explications of ISO examples of common datums are not matched with their corresponding definitions, and secondly: a full definition of common datum is missing. This paper suggests a new approach for an enhanced definition and concrete examples of common datum and proposes a holistic methodology for establishment of common datum for each geometrical component. This research is based on the analysis of physical behaviour of geometrical components, orientation constraints and invariance classes of datums. This approach fills the definition gaps of common datum based on ISO GPS, thereby eliminating those deficits. As a result, an improved methodology for a fully functional defined definition of common datum was formulated.

Due to the miniaturization process of the CMOS components metallization structures are becoming more and more complex. Better knowledge to improve via robustness for high current applications is needed. Geometry changes can have a big effect on the physical behaviour. For higher robust metallization systems it is necessary to learn more about overlap design to meet the most economic layout. Slotted high current line layouts do not allow the use of big via areas. Furthermore the number of vias increases the resistance. Investigations have shown the existence of an optimal overlap.

Recent trends in carrying out deterministic safety analysis for safety assessment are attracting more attention for the use of best estimate approach. However, conservative approaches are still used in licensing safety analysis. The best estimate approach provides more realistic information with respect to conservative approach for predictions of physical behaviour and provides information about the existing safety margins and between the results of calculation and regulatory acceptance criteria, whereas conservative approach also does not give any indication about actual plant behaviour, including time scale, for preparation of emergency operating procedures. Best estimate methodology results are affected by various sources of uncertainty like code or model uncertainty, representation uncertainty, scaling uncertainty and plant uncertainty. Therefore, uncertainty in the results due to unavoidable approximation in the modelling should be quantified. Various uncertainty analysis methodologies have been emerged after the development of code scaling, applicability and uncertainty (CSAU) by US NRC in 1989, like CIAU by Italy and GRS by Germany. This chapter deals with the sources of uncertainty and its quantifications by various methodologies in terms of confidence and probability. This chapter also deals with the application of a sampling-based uncertainty evaluation in the best estimate analysis of station blackout and small break LOCA in integral test facilities carried out under the framework of IAEA CRP. Uncertainty evaluation for TMI-II accident has been carried out using this methodology.

There exists a domain of models that is principially classified into the linear and non-linear fields of modelling. In the field of non-linear modelling, significant progress has been made since the 1960s thanks to the widespread and regularly available computer technology. This dynamic development influenced a large number of problems including the description of physical behaviour of non-trivial tasks. Non-linear models are solved in the material, spatial, and time domains. However, certain non-linear model domains are not sufficiently developed or regularly used for analysis of the more simple tasks. This group includes task models using non-linear discontinuous characteristics of materials, which can be exemplified by the change of state of a material during heating or cooling. In this section, we would like to use several descriptive examples to expose the problem of thermal tasks solution utilizing applied materials with a phase change (PCM) (Gille, T.; at al. 2007, Volle, F. at al. 2010, Shi, L.P.; at al. 2006). These are mostly coupled tasks (Fiala,P. December 1998). Within the specification of different aspects of the solution process, emphasis will be placed on the final accuracy of the results of numerical analyses, and therefore (rather than focusing on a complete description of the model) the text will accentuate problematic spots within the solution of such tasks. The PCM characteristics are demonstrated on the task of designing a low-temperature accumulator, an efficient cooler of electronic components, and a separator of impurities in an industrial oil emulsion.

In order to improve the predictive capability of the mathematical or numerical models of engineering structures, there is a need to capture their physical behaviour based on experimental measurements. In dynamics, this is accomplished with specific vibration tests, such as the Ground Vibration Test (GVT) used in aerospace applications. Currently, it seems that the engineering community lacks appropriate tools for the detection and quantification of dynamic nonlinearities during vibration tests. Of the nonlinear identification methods developed during the past 30 years, only a few are suitable for application on practical engineering structures. One of these has the particular advantage of requiring standard measurement techniques and sensors and is based on the analysis of Frequency Response Function (FRF) data. However, in many practical applications, structures are required to be tested by excitation of the base, so that transmissibilities are measured in place of FRFs. In this paper an existing identification method based on FRF data is shown to be applicable also when transmissibility is measured. Numerical simulations are used to demonstrate the applicability of the method.

Vehicular communication involves many decision making situations. The existing models for packet routing in VANET fails in cases needing fast decision making. Ambient Intelligence (AmI) system is a relatively new technique which aim at augmenting real environments where users are provided with pervasive virtual services. The ability to learn very quickly from the ambience of an object, and transforming that information into specific response involves a heterogeneous network comprising of vehicles, humans, and road side units. This paper proposes a modular architecture for information sensing, communicating, updation of knowledge-bas, etc, aimed at generating alarms in emergency situations. The emergency situation might involve abnormal physical behaviour, road blockage due to accidents or diversions, etc.

In this work, we present a system and methodology for using mobile phones for monitoring physical activities of a user, and its applications in assisting elderly and people with need for special care and monitoring. The method is based on processing acceleration data provided by accelerometers integrated in mobile phones. This information is sent to a monitoring server, analyzed and presented as different health related factors for assistance, monitoring and healthcare purposes. A monitoring agent can use a desktop application to observe pattern of physical activities of several users in a live manner, and receive warnings in case of unexpected physical conditions. The data can be also stored offline for longer term analysis of physical behaviour and health. The desktop application also provides different options for managing, browsing, and searching activity related data.

A virtual model to support decision-making in the planning of construction maintenance was developed. It gives the capacity to transmit, visually and interactively, information related to the physical behaviour of a specific component of a building, defined as a function of the time variable. The model helps to identify needs related to the lighting equipment of a building, namely, the cost involved in lamp replacement and control of stock, warnings of the need for periodic inspections and minimization of times when broken bulbs are left in place.

International Conference on Virtural Reality Continuum and Its Applications in Industry (VRCAI), Univ Singapore, Nanyang Technol, Singapore, SINGAPORE, JUN 15-18, 2004; International audience; The incorporation of physical behaviour to synthetic objects constructed by computer is one of the main objectives of computer graphics research. In this paper we present a new interactive deformable model based on linked volumes. As such, it is straightforward and implicitly preserves the volume of the modelled objects. The proposed model resorts to Lennard-Jones potential fields for the representation of the internal energy stored in the deformable objects. Experimental results show that this new deformable model can simulate the physical behaviour of elastic volumetric objects both in a realistic and interactive way. (c) 2004 Elsevier Ltd. All rights reserved.

The correct simulation and visualisation of textiles comprises many research fields such as mathematics, physics, materials science, and computer graphics. It consists of modelling the physical behaviour of textiles based on real data of garment patterns which have to be placed around an avatar. Therefore efficient numerical algorithms have to be developed to solve the appearing differential equations. Finally the obtained results are displayed photorealistically). The aim of the national research project "Virtual Try-On" consists in providing a prototype of a virtual try-on scenario in a real shop or the internet realizing cost-efficient made-tomeasure wear. In this article we present the whole process chain from the choice of clothes up to the final visualisation and the individual evaluation of fit.

We consider the problem of giving virtual reality objects physical behaviour. We wish to do this in a way, which allows users to construct new objects from simpler ones and have the correct composite behaviour emerge. Our approach uses a graph structure to model, dynamically, the way one object can influence another. It uses a lightweight message system to cause actions between objects. It has routines to encode each kind of general physical behaviour. Any given object can have multiple independent behaviours and these behaviours can be extended to give a richer range of outcomes. These outcomes arise from the creative use to which the objects are put by the user, rather than from predetermined actions built-in when the VE was designed. In addition, we replace hierarchical geometry modelling with a much flatter structure. We explain the approach, describe the implementation, suggest enhancements and offer a range of tests, which demonstrate the concepts in action

For the discussion of physical modeling methods used in chapters 4 to 6 for the simulation of acoustical instruments, a physical description of these instruments has to be derived first. Therefore, in this chapter musical instruments are briefly described with respect to their physical behaviour. Instrument families are discussed on one example, extensions to similar instruments are mentioned. First of all, section 1 presents the general notation used for the vibrational description of musical instruments. Then section 2 shows that a musical instrument can be subdivided with some simplifications into vibration generators and a resonant body. This is important for the synthesis algorithms described in chapters 4 and 5, because the separation allows a modular realization of the different parts of musical instruments.

Even relatively simple microwave circuits can become difficult to analyse, particularly if there are slight mismatches in the impedances between the components. More and more, computer analysis is being used to simulate the behaviour of microwave circuits, and this can provide very accurate results. The disadvantage of computer analysis is that it gives very little insight into the physical behaviour of the circuit.

Many injures during childhood are related to the use of playground equipment. Until recently, scientific data of how children actually use playground equipment were scarce. To design age-appropriate and safer playground equipment, it is essential that scientific data on children’s interaction with this equipment be accumulated. We developed a rock-climbing wall equipped with force sensors to record the physical behaviour of children while on the wall, thus allowing measurement of these behaviours in a more natural environment. Around 50 force sensors installed in the developed rock-climbing wall are able to collect a large amount of data while children are playing with the equipment. The behaviour data of 623 children were recorded in the present study. Herein, we report on a child behaviour prediction model created from the collected data.

The purpose of this chapter is to review the physical behaviour and characteristics of fading channels. After giving a description of multipath fading channels, we develop a statistical model for these channels. This model and its related parameters will be used throughout the book. Finally we introduce computer models for various kinds of fading channels which are useful in computer simulation of communication systems over fading channels.

The evolution of incidental sequences in a system is the combined result of stochastic and deterministic events, the former due to the failures of the components, the latter related to the physical behaviour of the system. The DYLAM-3 code for the reliability assessment of a system represents a powerful tool for integrating deterministic and failure events and it is essentially based on the systematic simulation of the physical process under study, both in nominal and in failed conditions. This paper describes the main features of the DYLAM-3 code with reference to a simple system already analyzed by other dynamic approaches. The same system is also studied with a time dependent fault tree approach in order to show some features of dynamic methods.

International audience; On a microscopic scale, a pyrotechnic material is made of a po lymer matrix containing grains with different sizes and shapes. Its physical behaviour can be predicted by homogenization. Information about the morphology of the grains can be obtained by different ways. O ne of these ways is 3D image processing. This has been made easier by the use of a new imaging technique , the microtomography, allowing fast three- dimensional reconstruction and processing. In this paper i mages of two granular materials are segmented by means of 3D mathematical morphology algorithms, based on a m ulti-scale extraction of markers for watershed segmentation.

The structure and operation of water distribution systems is explained briefly, and the basic mathematical tools used to analyze their physical behaviour are outlined. Methods for optimal planning, design and operation are presented and discussed. They are grouped according to the engineering problem which they address and to the method of solution. This survey is given at a level of detail which should suffice to understand each method and appreciate its potential and deficiencies. For more detail, or for actual implementation one has to refer back to the original works, which are listed at the end of the paper.

A new approach for the reliability analysis of coherent and non-coherent systems is presented with regard to the problem of the systematic generation of failure logical structures. In particular, this methodology allows us to derive the logical behaviour of the system by means of the physical behaviour of its components.

The design of electronic driving sources for ultrasonic machining, or more generally for macrosonics, is submitted to very constraining criteria. In fact, to the reliability and safety requirements which are imposed to any industrial device, specific constraints have to be added which are related to the physical behaviour of the acoustic load : the supply of energy to a piezoelectric transducer requires a power output stage which is particularly well matched and protected, frequency and impedance variations from one tool to another imply initial adjustments, important fluctuations under operating conditions make the automatic control essential and critical, the variations of the various parameters being large from one application to another, the design of each source is specific.

The earlier paper by Carter(1) described In a very general way how an eroding or growing surface can be described in terms of non-linear wave theory and some geometrical examples of developing surfaces have been described by Nobes(2). For many practical applications however, where the characteristics are not straight lines, only computational models allow detailed quantitative calculations to be made. In three dimensions even when the characteristics are linear, the geometrical nature of the surface is usually such that computer graphics have to be used in order to visualise the physical behaviour of the eroding or growing morphology.

In this paper, we propose a method that allows the robot to adapt its physical behaviour to the human fatigue in human-robot co-manipulation tasks. The robot initially imitates the human to perform the collaborative task in a leader-follower setting, using a feedback about the human motor behaviour. Simultaneously, the robot obtains the skill in online manner. When a predetermined level of human fatigue is detected, the robot uses the learnt skill to take over the physically demanding aspect of the task and contributes to a significant reduction of the human effort. The human, on the other hand, controls and supervises the high-level interaction behaviour and performs the aspects that require the contribution of both agents in such a dynamic co-manipulation setup. The robot adaptation system is based on the Dynamical Movement Primitives, Locally Weighted Regression and Adaptive Frequency Oscillators. The estimation of the human motor fatigue is carried out using a proposed online model, which is based on the human muscle activity measured by the electromyography. We demonstrate the proposed method with experiments on a real-world co-manipulation task with environmental constraints and dynamic uncertainties.

Human behaviour analysis through smartphone devices has been an active field for more than a decade and there are still a lot of key aspects to be addressed. This paper surveys the state-of-the-art in human behaviour analysis based on smartphones. We categorise prior works into four main sensing modalities related to physical, cognitive, emotional and social behaviour. Finally, we conclude with the outcomes of this survey and we illustrate our ideas for future research in the area of human behaviour understanding., This work has received funding from the European Union’s Horizon 2020 research and innovation programme under Grant Agreement #769553. This result only reflects the author’s view and the EU is not responsible for any use that may be made of the information it contains. This work has also been supported by the Dutch UT-CTIT project HoliBehave and in collaboration with the research project “Progress in Computer Architectures for Automatic Learning using Heterogeneous Sources: Health and Well-Being Applications” (TIN2015-71873-R).