Dynamic Adaptation Research Papers

SIMAP: Intelligent System for Predictive Maintenance:: Application to the health condition monitoring of a windturbine gearbox

by Mari Cruz Garcia

2006, Computers in Industry

SIMAP is the abbreviated name for the Intelligent System for Predictive Maintenance. It is a software application addressed to the diagnosis in real-time of industrial processes. It takes into account the information coming in real-time... more

Maintenance action information maintenance actions are presented by SIMAP in a format similar to that presented in Fig. 18.

Fig. 19. MP36 and MP24 maintenance sets efficiency evaluation.

Fig. 2. Maintenance task efficiency calculation. through the corresponding models of normal behaviour in order to estimate its predicted normal behaviour according to the current working conditions. Once this is completed, both pr- edicted and observed new sets of values are passed in parallel through the anomalies detection module and the health con-

Fig. 4. Temporal evolution of gearbox main variables.

Fig. 5. Normal behaviour model. Work scheme.

Fig. 7. Example of the normal behaviour model for the gearbox bearing temperature working in real-time. Fig. 7 shows an example of the performance of the model once it was fitted when it is receiving real information about its inputs. The figure shows the real bearing temperature of the gearbox, its estimated value from the model and the upper and lower confidence bands for the estimation along the time presented at a confidence level of 95%. The conclusion is that the prediction of the evolution of the gearbox bearing temperature corresponds well to the real evolution of this

Fig. 6. Normal behaviour model for the gearbox bearing temperature of the windturbine.

Fig. 8. Real and estimated gearbox bearing temperature when an anomaly is present.

Fig. 10. Real and estimated cooling oil temperature when an anomaly is present. According to Fig. | in parallel to the Anomalies Detection Module and also using as inputs the normal behaviour models

Fig. 9. Real and estimated gearbox thermal difference when an anomaly is present.

Fig. 11. Fuzzy certainty degree of diagnostics concluded.

Fig. 12. Evolutions for six histories of the failure mode FM1 of the residuals corresponding to the normal behaviour models of: (a) gearbox bearing temperature, (b gearbox thermal difference, (c) cooling oil temperature.

Fig. 14. Gearbox health condition during failure period. current evolution of the residual of the normal behaviour model for the gearbox main bearing temperature and the output of the residual model built with historic data of gearbox failures but excited with current conditions as inputs. Finally, it is possible

Fig. 13. (a—c) Fuzzy patterns for the residuals of the three normal behaviour models aggregating information of six histories that finished in the failure mode FM1.

Fig. 15. (a—d) Gearbox failure time forecasting.

Fig. 16. Similarity between residuals of current and pre-processed historical evolution of failure conditions.

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A sense of danger

by nauman mazhar

2008, Proceedings of the 10th annual conference on Genetic and evolutionary computation - GECCO '08

AIS based intrusion detection systems have traditionally performed self non-self discrimination and suffer from issues such as scalability, false positives, problems with detector generation/holes, need for an initial learning phase, etc.... more

Figure 1: Comparison of protocol average throughputs

Figure 2: Comparison of application data handed down by TCP layer for transporting to destination nodes

Figure 4: BeeAIS-DC Attack-1: Forging Forward Scout

Figure 5: BeeAIS-DC Attack-2: Forging Backward Scout

Figure 6: Performance results comparing BeeAIS-DC with BeeAdHoc, DSR and AODV

Table 3: List of BeeAIS-DC symbols and parameters

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Adaptive caching for demand prepaging

by Scott Kaplan

2002, ACM SIGPLAN Notices

Demand prepaging was long ago proposed as a method for taking advantage of high disk bandwidths and avoiding long disk latencies by fetching, at each page fault, not only the demanded page but also other pages predicted to be used soon.... more

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Dynamic adaptation of response-time models for QoS management in autonomic systems

by MANUEL ENRIQUE GARCIA

2011, Journal of Systems and Software

In transactional systems, the objectives of quality of service regarding are often specified by Service Level Objectives (SLOs) that stipulate a response time to be achieved for a percentile of the transactions. Usually, there are... more

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Dynamic data fusion for future sensor networks

by Rajnish Kumar

2006, ACM Transactions on Sensor Networks

DFuse is an architectural framework for dynamic application-specified data fusion in sensor networks. It bridges an important abstraction gap for developing advanced fusion applications that takes into account the dynamic nature of... more

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Improving power efficiency of D-NUCA caches

by Pierfrancesco Foglia

2007, ACM SIGARCH Computer Architecture News

D-NUCA caches are cache memories that, thanks to banked organization, broadcast search and promotion/demotion mechanism, are able to tolerate the increasing wire delay effects introduced by technology scaling. As a consequence, they will... more

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A models@runtime framework for designing and managing Service-Based Applications

by Jean-Louis Pazat

2012, 2012 First International Workshop on European Software Services and Systems Research - Results and Challenges (S-Cube)

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An Adaptive Data Prefetcher for High-Performance Processors

by Xian-he Sun

2010, 2010 10th IEEE/ACM International Conference on Cluster, Cloud and Grid Computing

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Autonomous Dynamic Power Control for Wireless Networks: User-Centric and Network-Centric Consideration

by ZORAN GAJIC

2000, IEEE Transactions on Wireless Communications

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Enabling self-management by using model-based design space exploration

by Abhishek Dubey

2010, … of Autonomic and …

Reconfiguration and self-management are important properties for systems that operate in hazardous and uncontrolled environments, such as inter-planetary space. These systems need a reconfiguration mechanism that provides recovery from... more

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Automatic Generation of Dynamic Tuning Techniques

by E. Fadón

2007, Lecture Notes in Computer Science

The use of parallel/distributed programming increases as it enables high performance computing. However, to cover the expectations of high performance, a high degree of expertise is required. Fortunately, in general, every parallel... more

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On-board Mining of Data Streams in Sensor Networks

by Sanghamitra Bandyopadhyay

2005, Advanced Information and Knowledge Processing

Knowledge discovery and data mining has recently emerged as an important research direction for extracting useful information from vast repositories of data of various types. This chapter discusses some of the basic concepts and issues... more

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Kinetic Structures in Architecture

by Marios Phocas

In the frame of integrated architectural design, the structural building design plays a most decisive role in supporting the areas of interdisciplinary development as regards form, construction and energy efficiency of the building. In... more

In all three static configurations of the dual system, the diagonals are fixed at the bottom of the columns and are capable to move at the top corners of the frame, through rotations of connecting eccentric discs. The bracing system forms a kinetic closed circuit, so that all braces remain at deformation state under tension. A hysteretic damper of triangular steel plates is connected between the frame and the respective bracing mechanism (Fig. 1). The control systems suggested, develop motion control forces at the points of attachment of the damper-bracing system. The relative motion of these points of attachment determines the amplitude and direction o f the control forces. As the deformation shape indicates, bracings are tensioning during every cycle of earthquake movement, maximizing the yielding potential, compared to the possible buckling of the steel members at a lower stress, if subjected to compression. Additionally the bracing’s ductility increases when the metallic dampers are supplemented at their optimal places. The steel damper utilizes the relative movement between the bracings and the frame, to yield under its shear or bending stress action, and dissipates a large proportion of the in put energy.

Figure 2 Energy dissipation behavior of the controlled systems according to earthquake characteristics Reaction forces on the primary frame elements in dual systems are neutralized, as in each load cycle the lengthening of a diagonal bracing tension member results to the shortening of the same length magnitude of the other bracing compression member. Energy dissipation takes mainly place through the hysteresis of the steel dampers. The suggested mechanisms incorporate hysteretic devices that dissipate energy with no significant rate dependence and operate on the principles of yielding of metals. The hysteretic dampers used in the dual systems consist of triangular steel plates, installed in parallel rows, typically within the respective idealized frame bay, between the bracing configurations and the primary frame elements. The steel dampers considered in the present study differ from the rectangular ones used in Phocas and Pocanschi (2003). Due to the triangular section shape, the bending curvature produced by the transverse force applying at the end of each plate is uniform over its full height, so that all steel triangular shaped section lines reach at the same time their yielding potential. The steel dampers dissipated much of the earthquake input energy and protected the more flexible ductile configuration system, in dependence to the characteristics of the ground motion (Fig. 2). Defining the variables t, b and h for the thickness, width, and height of a plate section respectively, and n, for the number of damper plates, the elastic lateral stiffness of the damper is given by the following equation:

The examination of the results on the relationship between the internal shear force at the ends of the damper model and the corresponding deformation for the three dual systems concluded that the dampers hysteretic loop can be grouped into three basic categories as indicated in Fig. 3. First representative example concerms the force-displacement relationship under the Etolia 88 earthquake for the dual system 3. It describes a rigid plastic behavior. Second group of behavior is represented by the loop developed by the dual system 1 under the Killini 88 earthquake. The behavior described by the graph is similar to an elastoplastic model. Finally a third group following the Ramberg-Osgood curve was distinguished, represented by the graph involving dual system 2 under the Ionian 83 earthquake. In all cases, the dampers primarily resisted the horizontal forces through bending deformations of the individual steel plates. Beyond a certain force-level (approximately 12.5 kN), the plates yielded and thus provided a supplemental amount of energy dissipation. The shape of the plates promoted nearly uniform yielding throughout their length. The resulting inelastic force deformation curves can be easily compared with experimental conclusions from past research studies, Tsai et.al. (1993), confirming the same characteristics in output behavior. The research study assured that the basic parameters determining the hysteretic behavior of the steel dampers are the yield displacement and stiffness of the device and the stiffness of the brace, with which the device is connected. Although the selection of triangular plates for the present analysis proved to be workable, further research study is needed to succeed in a more stable hysteretic curve shape under repeated loading cycles.

Figure 5 Base shear of dual systems In all loading cases, the base shear was reduced when dampers were incorporated to form the dual systems (Fig. 5). The base shear of the braced frames was slightly reduced compared to the bare frames. Especially for the configuration characterizing dual system 2, keeping exactly the same section properties, the system with the bracings performed better in at least 50 % of the cases compared to the bare frame, but the reduction when dampers were used was remarkably effective. Last graph in Fig. 5 attempts a comparison between the three different dual configurations. In 20 % of the cases dual system 3 performed better, whereas in one case it resulted in the worst reduction compared to the other two configuration systems. Dual system 2 was clearly better in 40 % of the cases, whereas dual system 1, in 10 % of the cases.

The structural performance of the three dual systems was examined against the ten time varying loads of actual earthquakes of the Greek-Mediterannean region, as shown in Table 3.1. Nonlinear time history structural analysis was carried out integrating SAP2000 program. Zero damping was considered for all excitations loading. As the analyses results revealed, the structural performance depends strongly on the dynamic characteristics of the seismic excitations.

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Phase Transitions, Chaos and Joint Action in the Life Space Foam

by Darryn Reid

2008, Arxiv preprint arXiv:0806.0690

Abstract: This paper extends our recently developed Life Space Foam (LSF) model of motivated cognitive dynamics\ cite {IA}. LSF uses adaptive path integrals to generate Lewinian force--fields on smooth manifolds, in order to characterize... more

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A Growth Model for the Quadruple Helix Innovation Theory

by Maria Thompson

2010

We propose a theoretical growth model with which to frame analytically the Quadruple Helix Innovation Theory (QHIT). The aim is to emphasise the investment in innovation transmission mechanisms in terms of economic growth and productivity... more

NUCLEO DE INVESTIGAGAO EM POLITICAS ECONOMICAS

which, for the adopted parameter values, is: Proposition 2 Everything else constant, an increase in the public investment

We have provided the QHIT with a first theoretical framework, where we have

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Dynamic adaptation of sharing granularity in dsm systems

by Assaf Schuster

2000, Journal of Systems and Software

The trade-o between false sharing elimination and aggregation in distributed shared memory (DSM DSM ) systems has a major eect on their performance. Some studies in this area show that ®ne grain access is advantageous, while others... more

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Dynamical Adaptive First and Second-Order Sliding Backstepping Control of Nonlinear Nontriangular Uncertain Systems

by Antonella Ferrara

2000, Journal of Dynamic Systems, Measurement, and Control

In this paper combined algorithms for the control of nontriangular nonlinear systems with unmatched uncertainties will be presented. The controllers consist of a combination of Dynamical Adaptive Backstepping (DAB) and Sliding Mode... more

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Adaptive VoIP transmission over heterogeneous wired/wireless networks

by Abdelbasset TRAD

2004

In this paper, we present an adaptive architecture for the transport of VoIP traffic over heterogeneous wired/wireless Internet environments. This architecture uses a VoIP gateway associated with an 802.11e QoS enhanced access point (QAP)... more

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Behavioral reactivity and real time programming in XML: functional programming meets SMIL animation

by Peter king

2004, … of the 2004 ACM symposium on …

XML and its associated languages are emerging as powerful authoring tools for multimedia and hypermedia web content. Furthermore intelligent presentation generation engines have begun to appear as have models and platforms for adaptive... more

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Security-driven model-based dynamic adaptation

by Y. Le Traon

2010, Proceedings of the IEEE/ACM international conference on Automated software engineering - ASE '10

Security is a key-challenge for software engineering, especially when considering access control and software evolutions. No satisfying solution exists for maintaining the alignment of access control policies with the business logic.... more

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Redline: First class support for interactivity in commodity operating systems

by Tongping Liu

2008

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Towards Dynamic Data-Driven Management of the Ruby Gulch Waste Repository

by Joel Saltz

2006, Lecture Notes in Computer Science

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Towards dynamic adaptability support for Master-Worker Paradigm component based applications

by Jean-Louis Pazat

2007, Towards Next Generation Grids

When executing scientific applications, resources that may be used can vary from multi-core processors to grids. Therefore, abstracting the programming model enables portability on various resource infrastructures. Furthermore, software... more

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Autonomic Wireless Sensor Networks : Intelligent Ubiquitous Sensing

by Gregory O'Hare

2006

Wireless Sensor Networks (WSNs) have the potential to radically transform commonly held perceptions of computing applications and usage. From environmental monitoring to assisting the aged in their everyday activities, the WSN concept... more

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Dynamic adaptation of broad phase collision detection algorithms

by V. Gouranton

2011, 2011 IEEE International Symposium on VR Innovation

In this paper we present a new technique to dynamically adapt the first step (broad phase) of the collision detection process on hardware architecture during simulation. Our approach enables to face the unpredictable evolution of the... more

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Reconfiguration in network of embedded systems: Challenges and adaptive tracking case study

by Liesbeth Steffens

2005

Many applications utilize deeply embedded sensors and actuators that are tightly coupled with the physical environment in order to perform their functionality. Sensor, actuators and embedded computation resources used for implementing... more

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Dynamic adaptation to critical care medical environment: error recovery as cognitive activity

by Vimla Patel

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A UPnP Service to Control and Manage IEEE 1451 Transducers in Control Networks

by Ralf Seepold

2000, IEEE Transactions on Instrumentation and Measurement

This paper describes a new universal plug-and-play (UPnP) device, i.e., the Sensor Manager (SM), and its associated network service to access and control smart transducer networks based on the IEEE 1451 standard. In terms of the IEEE... more

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eFlow: a platform for developing and managing composite e-services

by Ming-Chien Shan

2000, Proceedings Academia/Industry Working Conference on Research Challenges '00. Next Generation Enterprises: Virtual Organizations and Mobile/Pervasive Technologies. AIWORC'00. (Cat. No.PR00628)

Today, companies are using the Web to connect with their back-end systems and perform e-commerce transactions. The next chapter of the Internet story is the evolution of today's access/content focused portals into eservices hubs. While... more

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The PALIO Framework for Adaptive Information Services

by Vasilios Zarikas

2003, Cross-Platform Applications and Context-Aware Interfaces

This chapter describes the PALIO (Personalised Access to Local Information and services for tourists) service framework, focusing on its extensive support for service adaptation. The PALIO framework is currently used in the development of... more

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Distributed Agent Evolution with Dynamic Adaptation to Local Unexpected Scenarios

by William Spears

2006, Lecture Notes in Computer Science

This paper introduces a novel framework for designing multiagent systems, called "Distributed Agent Evolution with Dynamic Adaptation to Local Unexpected Scenarios" (DAEDALUS). Traditional approaches to designing multi-agent systems are... more

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Adaptation techniques for intrusion detection and intrusion response systems

by Daniel Ragsdale

SMC 2000 Conference Proceedings. 2000 IEEE International Conference on Systems, Man and Cybernetics. 'Cybernetics Evolving to Systems, Humans, Organizations, and their Complex Interactions' (Cat. No.00CH37166)

and intrusion response systems. As attacks on computer systems are becoming increasingly numerous and sophisticated, there is a growing need for intrusion detection and response systems to dynamically adapt to better detect and respond to... more

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Effects of acute and chronic treatment with fluoxetine on regional glucose cerebral metabolism in rats: implications for clinical therapies

by Mauro Dam

2000, Brain Research

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Multimedia Learning in Advanced Computer-based Contexts: `Discovering Trier

by Nicoletta Gagliardi

2008

Edutainment is a neologism that expresses the marriage of education and entertainment. In particular edutainment is a form of entertainment designed to educate as well as to amuse and typically seeks to instruct or socialize its audience... more

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A contemporary approach to hybrid expert systems case base reasoning

by Dharm Raj

In the presented paper, we proposed a concept of software realization of a hybrid expert system using case based reasoning. The presented paper focuses on that part of case-based reasoning system which is smoothly integrated into a... more

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A task graph execution manager for reconfigurable multi-tasking systems

by Carlos Gonzalez

2010

Reconfigurable hardware can be used to build multi-tasking systems that dynamically adapt themselves to the requirements of the running applications. This is especially useful in embedded systems, since the available resources are very... more

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Ontology-based author profiling of documents

by Ben Majer

2002

In this paper we present the advantages of using an ontology service for the modelling of user profiles in the EC FP5 IST project NAMIC (IST-1999-12392). By means of an ontology server people set up user profiles, which are in fact views,... more

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A Novel Architecture for IEEE 802.16 M Subscriber Station for Joint Power Saving Class Management

by Mayank Raj

2009, … of the First international conference on …

Abstract IEEE 802.16m amendment is being drafted to meet the 4G network requirements as an extension to 802.16e-2005. In 802.16e, a Subscriber Station (SS) can have multiple connections to a Base Station (BS) for supporting different... more

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Investigation of Future Optical Metro Ring Networks based on 100Gigabit Metro Ethernet (100GbME

by A. Gladisch

This paper reports results of a performance comparison for four optical ring network architectures envisaged for future metropolitan area networks (MANs), with particular emphasis on the design of and compatibility to possible... more

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A Robust, Fully Adaptive Hybrid Level-Set/Front-Tracking Method for Two-Phase Flows with an Accurate Surface Tension Computation

by Millena Villar

2010, Communications in Computational Physics

We present a fully adaptive hybrid method for the accurate simulation of incompressible two-phase flows in the presence of surface tension in two dimensions. The method is based on the hybrid level set/front-tracking approach proposed in... more

To handle the pressure-velocity coupling (4.7) and (4.8), we propose the projection nethod where p”t! and p"*! are given approximations of the pressure and of the density at t=t"t! respectively. Once the provisional velocity u* is computed from (4.9) imposing u* =u"! on the boundaries, it is projected onto the space of divergence-free vector fields. The projection step is accomplished by solving the Poisson equation for g defined by (4.10) and (4.11) along with homogeneous Neumann boundary conditions dq/dn = 0, where n is the unit normal exterior to the domain (see [47,48] for a discussion of the numerical boundary conditions for the Poisson equation during the projection step). a mee wer 866 a -— wie +9 Pe eae es -— £2 Ge se =

i me cea! Since I’ is a piecewise linear curve, the closest point ¢ on I to a given point x, either lies on one of the “edges” (links) or at one of the “vertices” (interface points). If ¢ lies on a edge, the vector from ¢ to x is orthogonal to the edge. Thus, the set of closest points to a given edge must lie within a strip defined by the edge itself and by its normal vector. In particular, the set of closest points within a specified distance € > 0 to a given edge is given by the polygon P seen in Figure 1.

Following the adaptive version of the IB method introduced by Roma et al. [32], we employ here the hierarchical grid structure proposed by Berger and Colella [55]. In our fully adaptive computational scheme, regions of the flow bearing special interest are cov- ered by block-structured grids, defined as a hierarchical sequence of nested, progres-

We end this section with a summary of a typical time step. For simplicity, we drop the i,j spatial indices. From computed values of p", the pressure at time t=", of X* and of u‘, k=n,n—1, the interface position and the velocity field at times t=t” and t= pod respectively, we update the pressure, the interface position, and the velocity field, by solving 4.5 Pressure-increment projection method

Table 1: L.. error approximations and numerical convergence ratios in the strips Q4 e Oz on a sequence of progressively finer adaptive meshes.

Figure 4: Initial and final interface locations.

Figure 5: Interface and 32x32 L5 composite grid at t=0, t=4, and t=8. Table 9: Standard deviation from Lagrangian equidistribution for a =4.0

Figure 6: Percentage of relative area loss for composite grids 32x32 L4 and 32x32 L5.

Figure 8: Comparison of interface positions for different adaptive mesh resolutions at t=2.13.

time behavior of the minimum distance between adjacent, opposite interfacial segments, Fig. 10, reveals a contrasting outcome. Slightly before t = 2.26, the decrease of the min- imum distance saturates, as clearly indicated by the two highest resolutions, 32 x 64 L6 and 32x64L7. At that instant, the minimum distance achieved is about 5 computational

Figure 10: Evolution of the minimum distance from disparate interface segments. This simulation provides only a glimpse of the complex rheology of a viscous fluid interface undergoing RT instability in the presence of surface tension and which can be accurately and efficiently captured with the proposed methodology. There is a number of important questions that remain open which include the limiting behavior as a) viscosity goes to zero and b) as surface tension goes to zero, as well as the effects of viscosity stratification. We intend to conduct a thorough investigation of these problems and will report on the results elsewhere.

Figure 12: Evolution of the density field superimposed with streamlines for a 32 x 64L5 composite grid simulation. The nested adaptive grid patches are also shown. Eo=1 and M=10-°. (a) t* =0.18, (b) t* =5.3, (c) #* =10.6, and (d) t* = 16.0. Se aad Ues* UV ENE CLIO £UUE GEEK Live IN VEL SNES pee Sen Ores Due to the interpolations at the interface, it is expected that the area (volume) of the bubble is only approximately conserved. Typically, the area loss grows linearly in time and with the mesh size. However, for this special case when the bubble keeps its shape unchanged, the area conservation of our IB-based method is much better than expected for both the hybrid force and the Lagrangian force formulations as Table 12 shows. The area is computed from the interface position variable X by applying Stokes theorem and approximating the resulting integral (with periodic integrand) with the trapezoidal rule. For this particular flow, the adaptive method with the hybrid force formulation preserves area with astonishing accuracy giving a relative area variation per characteristic time for the five-level grid of less than 10-°%. This unprecedented accuracy in the area conser- vation appears to be directly linked to the special, constant curvature nature of the fluid interface. It is interesting to note however that the adaptive, nonsymmetric grid was able to preserve that interface geometry and pressure-surface tension balance so accurately.

Figure 13: Evolution of the vorticity field for a 32 x64L5 composite grid simulation. Eo=1 and M=10~°. (a) t* =0.18, (b) t* =5.3, (c) #* = 10.6, and (d) t* = 16.0.

Figure 14: Rise Reynolds number against non-dimensional time on 32x64L5 grid cells.

Figure 15: Capillary pressure of a circular bubble with Eo=1 and M=10~?.

Figure 17: Evolution of the vorticity field for a 32 x32L9 simulation. (a) t* —t* = —1.22, (b) t* —t? = —0.56, (c) t* —t¥ =0.32, (d) t* —t? = 1.20, (e) t* —t? =2.07, (f) t* —t¥ =2.95, (g) t* —t* —3.83, (h)t* —t? =4.71, and (i) f° —t7 =5.59.

Figure 18: Interface position during impact of drop onto an interface. Comparison be- tween Zheng et al. [31] results on a unstructured mesh with 32 x 32L9 adaptive mesh. Dimensionless parameters: Re = 68, We = 7, Fr=1, pi /p2 = 0.33 o1/p2 = 1.189 and h/D =0.0035. The y axis has been shifted to coincide with the initial position of the free fluid interface.

Figure 20: Relative area variation of the drop for 32x32L9.

Figure 21: Close-ups of the 32 x 32L9 adaptive mesh at t* —t; =3.4. (a) A region enclosing the drop and part of the free boundary and (b) a close-up of the smallest gap region.

The numerical method that we introduce in the current work is hybrid in two different aspects and fully adaptive in space. It is hybrid first because we exploit qualities from both the IB Method (front-tracking) and from the level set formulation (front capturing) there o is the surface tension coefficient and t is a tangent unit vector. For constant irface tension, one can write (3.1) as We outline here the hybrid force formulation proposed in [34]. Let us begin with the Lagrangian approach for computing the interfacial force in IB-type methods,

where A(t) is the area of the circular droplet at time t. Table 4 compares the area loss at t= 250t, for the hybrid force (HF) and the standard Lagriangian force (LF) formulations using dynamic Lagrangian equidistribution for both and for La=12000. The hybrid force formulation yields consistently a smaller area loss than the Lagrangian force formulation and at high resolutions that difference can be about one order of magnitude or better. This behavior is the same for the set of La tested (1.2-12000).

Table 6: Magnitude Ca of the spurious currents on a sequence of adaptive grids for La = 12000. Non-uniformly distributed Lagrangian markers.

Table 11: Mean curvature x at 6 =7¢ and t* = 25, and percentage error when compared to the analytic value x =2/D = 66.6666.

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In Which Context Does Breakthrough Knowledge Grow?

by Journal of Iranian Public Administration Association

2018, Journal of Iranian Public Administration

In Which Context Does Breakthrough Knowledge Grow? Seyed Mehdi Alvani Abstract: Breakthrough Knowledge stems from a type of knowledge in which innovation is formed through novel thoughts and beliefs and not in gradual and incremental... more

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A rank based particle swarm optimization algorithm with dynamic adaptation

by reza akbari

2011, Journal of Computational and Applied Mathematics

The particle swarm optimization (PSO) technique is a powerful stochastic evolutionary algorithm that can be used to find the global optimum solution in a complex search space. This paper presents a variation on the standard PSO algorithm... more

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Chameleon: a software infrastructure for adaptive fault tolerance

by Saurabh Bagchi

1999, IEEE Transactions on Parallel and Distributed Systems

This paper presents Chameleon, an adaptive infrastructure, which allows different levels of availability requirements to be simultaneously supported in a networked environment. Chameleon provides dependability through the use of special... more

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Forecast adaptation to charge transfers

by Pedro Pereira Rodrigues

2004

This paper presents a study in neural networks for short-term predictions, in the scope of electric load forecasting in the presence of charge transfer scenarios. Charge transfers are humanprovoked transfers of electrical charge from one... more

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Redline: First class support for interactivity in commodity operating systems

by Eliot Moss

2008

While modern workloads are increasingly interactive and resource-intensive (e.g., graphical user interfaces, browsers, and multimedia players), current operating systems have not kept up. These operating systems, which evolved from core... more

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Dynamic adaptation of cardiac baroreflex sensitivity to prolonged exposure to microgravity: data from a 16-day spaceflight

by John M Karemaker

2008, Journal of Applied Physiology

This study explored the process of arterial baroreflex adaptation to microgravity, starting from the first day of flight, during the 16-day STS-107 Columbia Space Shuttle mission. Continuous blood pressure (BP), ECG, and respiratory... more

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An architecture-based dynamic adaptation model and framework for adaptive software systems

by Mohamed Hussein

2011, ACS/IEEE International Conference on Computer Systems and Applications

This paper describes an architecture-based dynamic adaptation model and framework for adaptive software systems. The framework provides for a reusable adaptation infrastructure and uses a layered architecture pattern. It also provides... more

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Specification of an ISDN Q.931 protocol entity using the LOTOS formal description technique

by Enrique Vazquez

1991, [1991 Proceedings] 6th Mediterranean Electrotechnical Conference

ABSTRACT A description is presented of the formal specification and implementation of the D-channel layer-3 protocol used in the user-network interface of the integrated services digital network. This protocol is informally defined in the... more

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Improving Control Performance Using Discrete Quality of Service Levels in a Real-Time System

by Scott Brandt

2004

Traditional control systems employ fixed sampling intervals. Recent work in integrated control and real-time systems has resulted in control systems in which the sampling interval may vary based on the state of controller performance.... more

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