Deterministic-stochastic subspace identification method for identification of nonlinear structures as time-varying linear systems This paper proposes the use of the deterministic-stochastic subspace identification (DSI) method, an input-output parametric linear system identification method, for characterization of nonlinear dynamic structural systems based on their time-varying amplitude-dependent instantaneous (i.e., based on short time-windows) modal parameters. Performance of the DSI method for estimation of instantaneous modal parameters of nonlinear systems is investigated using numerical as well as experimental data. In this study, DSI is used for extracting instantaneous modal parameters of single degree-of-freedom (SDOF) as well as 7-DOF systems with different hysteretic material behavior. Nonlinear responses of the SDOF and 7-DOF systems are simulated due to different seismic excitations using the OpenSees structural analysis software. Modal identification results are compared with those obtained using wavelet transform and the exact values. Effects of four input factors are studied on the variability of identified instantaneous modal parameters: (1) type of material nonlinearity, (2) level of nonlinearity, (3) input excitation, and (4) length of data windows used in the identification. The accuracy of the identified instantaneous modal parameters is evaluated along the response time history while varying the above mentioned input factors. Overall, DSI outperforms the wavelet transform for short-time/instantaneous modal identification of nonlinear structural systems and provides reasonably accurate results especially when the material hysteretic behavior is smooth such as the considered Giuffr-Menegotto-Pinto hysteretic model. Finally, DSI has been applied for short-time modal identification of a full-scale seven-story reinforced concrete shear wall structure based on its measured response to different seismic base excitations on a shake table. The identified instantaneous natural frequencies of the first vibration mode can accurately track the variation in the structure's effective stiffness along its response.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

deterministic-stochastic subspace identification method


Performance response of wireless channels for quantitatively different loss and arrival statistics ? In this paper we propose a cross-layer performance evaluation framework for wireless channels and subsequently explore the performance response at the FEC and ARQ enabled data-link layer in terms of frame losses and delays for different first- and second-order error and arrival statistics. For a wireless channel model to be appropriate for various FEC capabilities without the need for extensive measurements of the frame error process for each particular FEC code, the error process of the wireless channel is modeled at the physical layer. We assume weak stationary property for bit error observations and model them using a hidden Markov model. The associated parameters matching algorithm allows us to explicitly capture bit error rate and lag-1 autocorrelation of the bit error process. To explore the performance response of the wireless channel at the data-link layer, a cross-layer extension of the bit error model to the data-link layer is then developed. The performance of applications is evaluated using the queuing-theoretic approach that allows both arrival and error processes to be autocorrelated and still retains analytical tractability. The proposed methodology allows us to obtain estimators of frame loss and delay probabilities in the presence of FEC and ARQ procedures at the data-link layer eliminating the need for time-consuming simulations and extensive measurements of wireless channel characteristics for different error correction capabilities of the data-link layer. It is analytical in nature, efficient for small and moderate frame sizes and suitable for performance control purposes where fixed size frames are used at the data-link layer. Particularly, it provides a way to choose the required correction capability of the FEC code resulting in best possible performance at the data-link layer. Numerical results indicate that first- and second-order bit error and frame arrival statistics significantly affect performance parameters provided by a wireless channel and should be taken into account when choosing an appropriate correction capability of the FEC code for given wireless channel conditions.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

cross-layer modeling
fec optimization
queuing analysis


Free-surface flow over a semi-circular obstruction The fully non-linear free-surface flow over a semi-circular bottom obstruction was studied numerically in two dimensions using a mixed Eulerian-Lagrangian formulation. The problem was solved in the time domain that allows the prediction of a number of transient phenomena, such as the generation of upstream advancing solitary waves, as well as the simulation of wave breaking. A parametric study was performed for a range of values of the depth-based Froude number up to 2.5 and non-dimensional obstacle heights, alpha up to 0.9. When wave breaking does not occur, three distinct flow regimes were identified: subcritical, transcritical and supercritical. When breaking occurs it may be of any type: spilling, plunging or surging. In addition, for values of the Froude number close to 1, the upstream solitary waves break. A systematic study was undertaken to define the boundaries of each type of breaking and non-breaking pattern and to determine the drag and lift coefficients, free-surface profile characteristics and transient behavior. Copyright (C) 1999 John Wiley & Sons, Ltd.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

eulerian-lagrangian formulation
free-surface flow
semi-circular obstruction


A note on the strong and weak generative powers of formal systems This paper is a note on some relationships between the strong and weak generative powers of formal systems, in particular, from the point of view of squeezing more strong power out of a formal system without increasing its weak generative power. We will comment on some old and new results from this perspective. Our main goal of this note is to comment on the strong generative power of context-free grammars, lexicalized tree-adjoining grammars (and some of their variants) and Lambek grammars, especially in the context of crossing dependencies, in view of the recent work of Tiede (Ph.D. Dissertation, Indiana University, Bloomington, 1999). (C) 2002 Elsevier Science B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O

lexicalized tree-adjoining grammars
multi-component grammars
strong generative capacity
tree insertion grammars


The relationship between Internet identification, Internet anxiety and Internet use This paper reports a study investigating the relationship between Internet identification, Internet anxiety and Internet use. The participants were 446 students (319 females and 127 males) from two universities in the UK and one university in Australia. Measures of Internet identification and Internet anxiety were developed. The majority of participants were NOT anxious about using the Internet, although there were approximately 8% who showed evidence of Internet anxiety. There was a significant and negative relationship between Internet anxiety and Internet use. Those who were more anxious about using the Internet used the Internet less, although the magnitude of effect was small. There was a positive and significant relationship between Internet use and Internet identification. Those who scored high on the measure of Internet identification used the Internet more than those who did not. There was also a significant and negative relationship between Internet anxiety and Internet identification. Finally, males had a significantly higher Internet identification score than females. Implications of these findings are discussed.

O O O B I B I O B I O O O O O O O O O B I B I O B I O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O B I O B I O O O O O O B I O O O O O O O O O

internet anxiety
internet identification
internet use


Stabilisation of walking by intrinsic muscle properties revealed in a three-dimensional muscle-driven simulation A fundamental question in movement science is how humans perform stable movements in the presence of disturbances such as contact with objects. It remains unclear how the nervous system, with delayed responses to disturbances, maintains the stability of complex movements. We hypothesised that intrinsic muscle properties (i.e. the forcelengthvelocity properties of muscle fibres and tendon elasticity) may help stabilise human walking by responding instantaneously to a disturbance and providing forces that help maintain the movement trajectory. To investigate this issue, we generated a 3D muscle-driven simulation of walking and analysed the changes in the simulation's motion when a disturbance was applied to models with and without intrinsic muscle properties. Removing the intrinsic properties reduced the stability; this was true when the disturbing force was applied at a variety of times and in different directions. Thus, intrinsic muscle properties play a unique role in stabilising walking, complementing the delayed response of the central nervous system.

O O B O O B O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O B O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O B O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O


Molecular recognition of avirulence protein (avrxa5) by eukaryotic transcription factor xa5 of rice (Oryza sativa L.): Insights from molecular dynamics simulations Highlights geneforgene hypothesis involving xa5avrxa5 of Rice-Xoo. In this study we have employed molecular docking, MD simulation and MM/PBSA methods. MD simulation revealed key residues involved in molecular recognition of avrxa5. MM/PBSA Binding energy calculation emphasized van der Waals term is the driving force for molecular recognition.

O O O O O O O O O O O O O O O O O O B I O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

hypersensitive response (hr)
mm/pbsa
structural biology
binding free energy


Improving TCP performance over asymmetric networks Bandwidth asymmetry is quite common among modern networks; e.g, ADSL, cable TV, wireless, and satellite link with a terrestrial return path. In these networks, the bandwidth over one direction can be orders of magnitude smaller than that over the other. The performance of TCP transfer in the high band-width direction can be severely reduced by the delay of acknowledgment packets experienced in the reverse direction. In this paper we describe our proposed solution ACE (Acknowledgment Based on Cwnd Estimation). In comparison to other solutions, ACE requires only modification of the TCP stack at terminals attached to m asymmetric network. We evaluated the performance of ACE over a cable modem network by simulation. We have also implemented ACE on the Linux platform and tested it on a small testbed network with an emulated asymmetric link. The performance Improvement was significant especially when there is a high degree of asymmetry.

O B O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

asymmetric networking
ack filtering
congestion window estimation


A Robust State Observer Using Multiple Integrators for Multivariable LTI Systems This paper proposes a robust state observer for multi-input multi-output LTI systems. Unknown inputs of polynomial form and high-frequency measurement noises are considered in the system model. The unknown inputs and the noises are not in the same form. Multiple integrations of both the observer error signal and the measurement output are used for the observer design. The existence condition of the proposed observer is shown to be the same as that of the proportional-integral (PI) observer. Computer simulations show the effectiveness of the proposed observer.

O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

proportional integral observer
unknown input
measurement noise


Interpolation methods and the accuracy of lattice-Boltzmann mesh refinement A lattice-Boltzmann model to solve the equivalent of the NavierStokes equations on adaptively refined grids is presented. A method for transferring information across interfaces between different grid resolutions was developed following established techniques for finite-volume representations. This new approach relies on a spacetime interpolation and solving constrained least-squares problems to ensure conservation. The effectiveness of this method at maintaining the second order accuracy of lattice-Boltzmann is demonstrated through a series of benchmark simulations and detailed mesh refinement studies. These results exhibit smaller solution errors and improved convergence when compared with similar approaches relying only on spatial interpolation. Examples highlighting the mesh adaptivity of this method are also provided.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

lattice-boltzmann
adaptive mesh refinement
poiseuille flow
taylorgreen vortex


Detailed modelling, implementation and simulation of an "all-in-one" stability test system including power system protective devices This paper presents modelling and simulation results for multiple instability scenarios of the "all-in-one" test system. The test system is an alteration of the Bonneville Power Administration test system constructed to capture transient (angle), frequency and voltage instability phenomena, resulting in system collapse, within one system. The paper describes general overview of the test system and its associated individual devices modelling. These modelling are both customized and adapted from the built-in model developed by PowerFactory simulation software. The paper also provides a description of different instabilities that can be reproduced by this self-contained system. One of the case study is demonstrated in detail with the necessary initialization settings for reproducing instability scenario. (C) 2012 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

power system simulation
power system modelling
power system stability
protection systems


Intelligent pattern detection and compression. An application to very low bit rate transmission of ship wake aerial images In land or sea surveillance systems, images taken from satellites or aerial platforms must be compressed and transmitted to a ground station for subsequent processing. If the employed platform is an airborne HAAP whose main purpose is to provide mobile/personal communication services over sea or impervious areas, major problems could arise for the transmission of images on radio-mobile compatible (e.g. GSM) channels, due to the very low available bit rate. A first stage detection algorithm could be recommended, to be run on board in order to transmit only those images which are likely to contain the patterns of interest. Moreover, this first stage detection could help performing an intelligent compression, so as to accurately preserve the objects of interest at the expenses of an impaired quality of the recovered background, which may be of negligible interest. In this paper, we address two joint detectioncompression algorithms suitable for the recognition of ship wakes in sea images. The algorithms have proven to yield very high compression ratios while preserving the objects of interest.

O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


service-oriented autonomic multimodal interaction in a pervasive environment Heterogeneity and dynamicity of pervasive environments require the construction of flexible multimodal interfaces at run time. In this paper, we present how we use an autonomic approach to build and maintain adaptable input multimodal interfaces in smart building environments. We have developed an autonomic solution relying on partial interaction models specified by interaction designers and developers. The role of the autonomic manager is to build complete interaction techniques based on runtime conditions and in conformity with the predicted models. The sole purpose here is to combine and complete partial models in order to obtain an appropriate multimodal interface. We illustrate our autonomic solution by considering a running example based on an existing application and several input devices.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

multimodal interaction model
component-based approach
design and implementation tool


Automatic generation of textual summaries from neonatal intensive care data Effective presentation of data for decision support is a major issue when large volumes of data are generated as happens in the Intensive Care Unit (ICU). Although the most common approach is to present the data graphically, it has been shown that textual summarisation can lead to improved decision making. As part of the BabyTalk project, we present a prototype, called BT-45, which generates textual summaries of about 45 minutes of continuous physiological signals and discrete events (e.g.: equipment settings and drug administration). Its architecture brings together techniques from the different areas of signal processing, medical reasoning, knowledge engineering, and natural language generation. A clinical off-ward experiment in a Neonatal ICU (NICU) showed that human expert textual descriptions of NICU data lead to better decision making than classical graphical visualisation, whereas texts generated by BT-45 lead to similar quality decision-making as visualisations. Textual analysis showed that BT-45 texts were inferior to human expert texts in a number of ways, including not reporting temporal information as well and not producing good narratives. Despite these deficiencies, our work shows that it is possible for computer systems to generate effective textual Summaries of complex continuous and discrete temporal clinical data. (c) 2008 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

natural language generation
intensive care unit

intelligent data analysis
decision support systems


uniqueness inference for compile-time object deallocation This paper presents an analysis and transformation for individual object reclamation in Java programs. First, we propose a uniqueness inference algorithm that identifies variables and object fields that hold unique references. The algorithm performs an intra-procedural analysis of each method, and then builds and solves a set of inter-procedural uniqueness dependencies to find the global solution. Second, our system uses the uniqueness information to automatically instrument programs with explicit deallocation of individual objects. A key feature of the transformation is its ability to deallocate entire heap structures, including recursive structures, when their root objects are freed. This is achieved by generating object destructors that recursively free all of the unique object fields. Our experiments show that the analysis is effective at reclaiming a large fraction of the objects at a low analysis cost.

B I O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

program transformations
individual object deallocation
compile-time memory management


MONTE CARLO SIMULATION OF POSITIVE CORONA DISCHARGE IN NITROGEN The corona discharge commonly occurs in many engineering devices and processes. Their application is still largely based on empirical knowledge; accordingly it is very important to predict the physical properties of corona discharge by the appropriate numerical method. To control corona discharge properly by understanding of corona discharge properties at different discharge stages, time-varying characteristics of discharge which are resulted from electron collision with the gas molecules should be investigated. A numerical study of a corona discharge in nitrogen in a point to plane geometry is presented. It is obtained by Monte Carlo method and concerns space-time evolution of electron and ion densities as well as electric field distributions along the discharge axis.

B I B O O B B O O O B B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B B O O O O O O O B B O O O O B B O O O B O O O O B O O O O O O O O O O O O O O O O O O B B O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I O O O B O

corona
discharge
electric field
monte carlo
simulation


Efficient and effective array bound checking Array bound checking refers to determining whether all array references in a program are within their declared ranges. This checking is critical for software verification and validation because subscripting arrays beyond their declared sizes may produce unexpected results, security holes, or failures. It is available in most commercial compilers but current implementations are not as efficient and effective as one may have hoped: (1) the execution times of array bound checked programs are increased by a factor of up to 5, (2) the compilation times are increased, which is detrimental to development and debugging, (3) the related error messages do not usually carry information to locate the faulty references, and (4) the consistency between actual array sizes and formal array declarations is not often checked. This article presents two optimization techniques that deal with Points 1, 2, and 3, and a new algorithm to tackle Point 4, which is not addressed by the current literature. The first optimization technique is based on the elimination of redundant tests, to provide very accurate information about faulty references during development and testing phases. The second one is based on the insertion of unavoidable tests to provide the smallest possible slowdown during the production phase. The new algorithm ensures the absence of bound violations in every array access in the called procedure with respect to the array declarations in the calling procedure. Our experiments suggest that the optimization of array bound checking depends on several factors, not only the percentage of removed checks, usually considered as the best improvement measuring metrics. The debugging capability and compile-time and run-time performances of our techniques are better than current implementations. The execution times of SPEC95 CFP benchmarks with range checking added by PIPS, our Fortran research compiler, are slightly longer, less than 20%, than that of unchecked programs. More problems due to functional and data recursion would have to be solved to extend these results from Fortran to other languages such as C, C++, or Java, but the issues addressed in this article are nevertheless relevant.

O O O B I I B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Development of a visualization tool for integrated surface watergroundwater modeling An efficient data visualization tool designed for integrated hydrological modeling. The software helps fill the gap between the integrated modeling and decision-making. The visualization can improve the understanding on the basin-scale hydrologic cycle.

O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

scientific visualization
gsflow
heihe river basin
water resources management


The HARPSS process for fabrication of precision MEMS inertial sensors The high aspect-ratio combined poly- and single-crystal silicon micromachining technology (HARPSS) and its application to fabrication of precision MEMS inertial sensors are presented. HARPSS is a single wafer, all silicon, front-side release process which is capable of producing 10-100's of microns thick, electrically isolated, 3-D poly- and single-crystalline silicon microstructures with various size air-gaps ranging from sub-micron to tens of microns. High aspect-ratio (>50:1) polysilicon structures are created by refilling 100's of microns deep trenches with polysilicon deposited over a sacrificial oxide layer. This technology provides features required for precision micromachined inertial sensors. The all-silicon feature of this technology improves long term stability and temperature sensitivity while fabrication of large area, vertical electrodes with sub-micron gap spacing will increase the sensitivity by orders of magnitude. (C) 2002 Published by Elsevier Science Ltd.

O O O O O O O B B I O O O O O O O B I O O O O O O O O O B B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

silicon micromachining
mems
inertial sensors

polysilicon micromachining
deep reactive ion etching
gyroscope


designing an e-mentoring application for facebook Facebook is the most popular social networking site, with more than 500 million active members. It has brought new opportunities for the learning and career development of students that live with technology and networked communications. This study explores the design of an e-mentoring Facebook application intended to bring together students, faculty, and Information Technology (IT) professionals as mentors and mentees.

O O O O O B B O O O O B I O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O

career development
social networking
facebook

computer mediated communication
e-mentoring


Numerical calculation of wear in mechanical systems The simulation of wear processes is dominated by the feedback between system dynamics and wear, which have completely different characteristic time scales. We present a method for decoupling the time scales. Its central ideas are the introduction of a wear density on the entire wearing surface and the establishment of an evolution equation in the slow time scale. The sample problem of a wearing disk rolling on a rigid rail is studied. In particular. we discuss the non-monotonous influence of the speed on the wear evolution and on the polygonalization of wheels. (C) 2011 IMACS. Published by Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

numerical wear simulation
polygonalization of railway wheels
multiple time scales


using csim to model complex systems Simulation models of complex systems, defined here to be systems with large number of activities or resources or with activities which exhibit complex behavior patterns, make severe requirements on simulation packages. These requirements are in the form of expressiveness (can you express the complexity in the language of the model?) and in the form of accommodation (can the runtime environment handle the large number of simulation objects?). This paper describes CSIM, a process-oriented simulation language based on C, and the features of CSIM which make it useful in developing and executing models of complex systems.

O O O B O B B O O O B O O O O B O O O O O O O O O O O O O B O O O B O B O O B O O O O O O O O B O B O O B O O B O O O O O O O O B O O O O O O B O O B O O O O B B O O O O O O O O O O O O O O O O O O O B

requirements systems simulation language behavior express complexity paper model runtime

activation
environments
packaging
object
complex systems
process
feature
resource
pattern


Fast multilevel augmentation methods for nonlinear boundary value problems We develop a multilevel augmentation method for solving nonlinear boundary value problems. We first describe the multilevel augmentation method for solving nonlinear operator equations of the second kind which has been proposed in our recent paper Chen etal. (2011)[16], and then apply it to solving the nonlinear two-point boundary value problems of second-order differential equations. The theoretical analysis of convergence order and computational complexity are proposed. Finally numerical experiments are presented to confirm the theoretical estimates and illustrate the efficiency of the method.

O B I I O B I I I O O O O O O O O B I I I O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

multilevel augmentation methods
nonlinear operator equations
nonlinear boundary value problems


Making my own luck: Serendipity strategies and how to support them in digital information environments Serendipity occurs when unexpected circumstances and an aha moment of insight result in a valuable, unanticipated outcome. Designing digital information environments to support serendipity can not only provide users with new knowledge, but also propel them in directions they might not otherwise have traveled insurprising and delighting them along the way. As serendipity involves unexpected circumstances it cannot be directly controlled, but it can be potentially influenced. However, to the best of our knowledge, no previous work has focused on providing a rich empirical understanding of how it might be influenced. We interviewed 14 creative professionals to identify their self-reported strategies aimed at increasing the likelihood of serendipity. These strategies form a framework for examining ways existing digital environments support serendipity and for considering how future environments can create opportunities for it. This is a new way of thinking about how to design for serendipity; by supporting the strategies found to increase its likelihood rather than attempting to support serendipity as a discrete phenomenon, digital environments not only have the potential to help users experience serendipity but also encourage them to adopt the strategies necessary to experience it more often.

O O O O B O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O


On the extent of correlation in BGP updates in the Internet and what it tells us about locality of BGP routing events The Border Gateway Protocol (BGP) is the core routing protocol in the Internet. It maintains reachability information towards IP networks, called prefixes. The adoption of BGP has come at a price: a steady growth in the routing table size (Meng et al., 2005) [1] as well as BGP updates (Cittadini et al., 2010)[2]. In this work, we take a different look at BGP updates, by quantifying the amount of prefix correlation in the BGP updates received by different routers in the Internet. We design a method to classify sets of BGP updates, called spikes, into either correlated or non-correlated, by comparing streams of BGP updates from multiple vantage points. Based on publicly available data, we show that a significant fraction of all BGP updates are correlated. Most of these correlated spikes contain updates for a few BGP prefixes only. When studying the topological scope of the correlated spikes, we find that they are relatively global given the limited AS hop distance between most ASs in the Internet, i.e., they propagate at least 2 or 3 AS hops away. Most BGP updates visible from publicly available vantage points are therefore related to small events that propagate across multiple AS hops in the Internet, while a limited fraction of the BGP updates appear in large bursts that stay mostly localised. Our results shed light on a fundamental while often misunderstood aspect of BGP, namely the correlation between BGP updates and how it impacts our beliefs about the share of local and global BGP events in the Internet. Our work differs from the literature in that we try as much as possible to explicitly account in our methodology for the visibility of BGP vantage points, and its implication on the actual claims that can be made from the data. (C) 2013 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

interdomain routing
bgp update correlation
bgp propagation


An analytic approach to select data mining for business decision Due to the information technology improvement and the growth of internet, enterprises are able to collect and to store huge amount of data. Using data mining technology to aid the data processing, information retrieval and knowledge generation process has become one of the critical missions to enterprise, so how to use data mining tools properly is user concern. Since not every user completely understand the theory of data mining, choosing the best solution from the functions which data mining tools provides is not easy. If user is not satisfied with the outcome of mining, communication with IT employees to adjust the software costs lots of time. To solve this problem, a selection model of data mining algorithms is proposed. By analyzing the content of business decision and application, user requirements will map to certain data mining category and algorithm. This method makes algorithm selection faster and reasonable to improve the efficiency of applying data mining tools to solve business problems.

O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O B I O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O B I O O O O O

data mining
business decision
selection model


Calmness of the Argmin Mapping in Linear Semi-Infinite Optimization This paper characterizes the calmness property of the argmin mapping in the framework of linear semi-infinite optimization problems under canonical perturbations; i.e., continuous perturbations of the right-hand side of the constraints (inequalities) together with perturbations of the objective function coefficient vector. This characterization is new for semi-infinite problems without requiring uniqueness of minimizers. For ordinary (finitely constrained) linear programs, the calmness of the argmin mapping always holds, since its graph is piecewise polyhedral (as a consequence of a classical result by Robinson). Moreover, the so-called isolated calmness (corresponding to the case of unique optimal solution for the nominal problem) has been previously characterized. As a key tool in this paper, we appeal to a certain supremum function associated with our nominal problem, not involving problems in a neighborhood, which is related to (sub)level sets. The main result establishes that, under Slater constraint qualification, perturbations of the objective function are negligible when characterizing the calmness of the argmin mapping. This result also states that the calmness of the argmin mapping is equivalent to the calmness of the level set mapping.

B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O B O O O O O O O O B O O O O O

local error bounds
variational analysis
semi-infinite programming
linear programming


Homogeneous NiSi1?xGex layer formation on strained SiGe with ultrathin Ni layers Homogeneous germanosilicide layers are formed on strained SiGe. Ni layer thickness and annealing temperature influence the germanosilicide layers phase and morphology. Strain in remaining SiGe can be conserved with the optimized process.

O O O O O O B O O O O O B O O O O O B O O O O O O O O B O O O O B O O B O O O O O O O


Technostress in the office: a distributed cognition perspective on humantechnology interaction Technology is a mobile and integral part of many work places, and computers and other information and communication technology have made many users work life easier, but technology can also contribute to problems in the cognitive work environment and, over time, create technostress. Much previous research on technostress has focused on the use of digital technology and its effects, measured by questionnaires, but in order to further examine how technostress arises in the modern workplace, a wider perspective on interactions between people and technology is needed. This paper applies a distributed cognition perspective to humantechnology interaction, investigated through an observational field study. Distributed cognition focuses on the organisation of cognitive systems, and technostress in this perspective becomes an emergent phenomenon within a complex and dynamic socio-technical system. A well-established questionnaire was also used (for a limited sample), to gain a frame of reference for the results from the qualitative part of the study. The implications are that common questionnaire-based approaches very well can and should be complemented with a broader perspective to study causes of technostress. Based on the present study, a redefinition of technostress is also proposed.

B O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O B O O O

technostress
distributed cognition
cognitive work environment

information and communication technology (ict)


escript-RT: Reactive transport simulation in Python using escript We present escript-RT, a new reactive transport simulation code for fully saturated porous media which is based on a finite element method (FEM) combined with three other components: (i) a Gibbs minimisation solver for equilibrium modelling of fluidrock interactions, (ii) an equation of state for pure water to calculate fluid properties and (iii) a thermodynamically consistent material database to determine rocks' material properties. Using decoupling of most of the standard governing equations, this code solves sequentially for temperature, pressure, mass transport and chemical equilibrium. In contrast, pressure and Darcy flow velocities are solved as a coupled system. The reactive transport itself is performed using the masses of chemical elements instead of chemical species. In such way it requires less computing memory and time than the majority of other packages. The code is based on escript, a parallelised platform which supports efficient stepwise simulation of realistic geodynamic scenarios at multiple scales. It is particularly suitable to analyse hydrothermal systems involving geometrically complex geological structures with strong permeability contrasts and subject to complex fluidrock chemical interactions. The modular architecture of the code and its high level Python interface also provide flexibility for modellers who can easily modify or add new feedbacks between the different physical processes. In addition, the implemented abstract user interface allows geologists to run the code without knowledge of the underlying numerical implementation. As an example we show the simulation of hydrothermal gold precipitation in a granitegreenstone geological sequence, which illustrates the important coupling between thermal response and mass transfer to the localisation of gold.

O B I O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

reactive transport
modular architecture
python

thermodynamics
geochemistry
finite elements


a simple decorrelate-and-forward relaying scheme for multiuser wireless cdma networks Decorrelate-and-forward (DCF) relaying for multiuser wireless CDMA networks with equicorrelated spreading sequences is developed and analyzed. By employing a simple near-far resistant decorrelator together with a precoding technique at each relay and the maximal-ratio-combiner (MRC) at the destination, it is shown that the full cooperative diversity order can be obtained for every user. Furthermore, the fairness among the users in terms of the instantaneous signal-to-noise ratio is significantly improved by exercising a power allocation scheme obtained with geometric programming (GP).

O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B I O

geometric programming
power allocation
cdma

decorrelate-and-forward relaying
wireless relay networks
beamforming


Evaluating a domain-specialist-oriented knowledge management system We discuss the evaluation of software tools whose purpose is to assist humans to perform complex creative tasks. We call these creative task assistants (CTAs) and use as a case study CODE4, a CTA designed to allow domain specialists to manage their own knowledge base. We present an integrated process involving evaluation of usability, attractiveness and feature contribution, the latter two being the focus. To illustrate attractiveness evaluation, we assess whether CODE4 has met its objective of having users not trained in logical formalisms choose the tool to represent and manipulate knowledge in a computer. By studying use of the tool by its intended users, we conclude that it has met this objective. To illustrate feature contribution evaluation, we assess what aspects of CODE4 have in fact led to its success. To do this, we study what tasks are performed by users, and what features of both knowledge representation and user interface are exercised. We find that features for manipulating the inheritance hierarchy and naming concepts are considered the most valuable. Our overall conclusion is that those developing or researching CTAs would benefit from using the three types of evaluation in order to make effective decisions about the evolution of their products. (C) 2000 Academic Press.

O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

software evaluation
creative task assistant


Manual sorting of numerals in an inflective language for language modelling In speech recognition systems language models are used to estimate the probabilities of word sequences. In this paper special emphasis is given to numeralswords that express numbers. One reason for this is the fact that in a practical application a falsely recognized numeral can change important content information inside the sentence more than other types of errors. Standard \(n\)-gram language models can sometimes assign very different probabilities to different numerals, according to their relative frequencies in training corpus. Based on the assumption that some different numbers are more equally likely to occur, than what a standard \(n\)-gram language model estimates, this paper proposes several methods for sorting numerals into classes in an inflective language and language models based on these sorting techniques. We treat these classes as basic vocabulary units for the language model. We also expose the differences between the proposed language models and well known class-based language models. The presented approach is also transferable to other classes of words with similar properties, e.g. proper nouns. Results of experiments show that significant improvements are obtained on numeral-rich domains. Although numerals represent only a small portion of words in the test set, a relative reduction in word error rate of 1.4% was achieved. Statistical significance tests were performed, which showed that these improvements are statistically significant. We also show that depending on the amount of numerals in a target domain the improvement in performance can grow up to 16% relative.

B I O B O O O O O O O O B I O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O

speech recognition
language models
numerals
manual sorting


Platform to drive an intelligent wheelchair using facial expressions Many of the physically injured use electric wheelchairs as an aid to locomotion. Usually, for commanding this type of wheelchair, it is required the use of one's hands and this poses a problem to those who, besides being unable to use their legs, are also unable to properly use their hands. The aim of the work described here, is to create a prototype of a wheelchair command interface that do not require hand usage. Facial expressions were chosen instead, to provide the necessary visual information for the interface to recognize user commands. The facial expressions are captured by a digital camera and interpreted by an application running on a laptop computer on the wheelchair. The software includes digital image processing algorithms for feature detection, such as colour segmentation and edge detection, followed by the application of a neural network that uses these features to detect the desired facial expressions. A simple simulator, built on top of the known (Ciber-Mouse) was used to validate the approach by simulating the control of the intelligent wheelchair in a hospital environment. The results obtained from the platform provide strong evidence that it is possible to comfortably drive an intelligent wheelchair using facial expressions.

O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O B I O O O

human-computer interface
computer vision
artificial intelligence


Encounter-based worms: Analysis and defense An encounter-based network is a frequently disconnected wireless ad hoc network requiring immediate neighbors to store and forward aggregated data for information disseminations. Using traditional approaches such as gateways or firewalls to deter worm propagation in encounter-based networks is inappropriate. We propose a worm interaction approach that relies upon automated beneficial worm generation to alleviate problems of worm propagations in such networks. To understand the dynamics of worm interactions and their performance, we mathematically model worm interactions based on major worm interaction factors, including worm interaction types, network characteristics, and node characteristics using ordinary differential equations and analyze their effects on our proposed metrics. We validate our proposed model using extensive synthetic and trace-driven simulations. We find that all worm interaction factors significantly affect the pattern of worm propagations. For example, immunization linearly decreases the infection of susceptible nodes, while onoff behavior only impacts the duration of infection. Using realistic mobile network measurements, we find that encounters are bursty, multi-group, and non-uniform. The trends from the trace-driven simulations are consistent with the model, in general. Immunization and timely deployment seem to be most effective in countering worm attacks in such scenarios, while cooperation may help in a specific case. These findings provide insight that we hope would aid in the development of counter-worm protocols in future encounter-based networks.

O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

encounter-based worms
delay-tolerant networks


Annotation-based feature extraction from sets of SBML models Model repositories such as BioModels Database provide computational models of biological systems for the scientific community. These models contain rich semantic annotations that link model entities to concepts in well-established bio-ontologies such as Gene Ontology. Consequently, thematically similar models are likely to share similar annotations. Based on this assumption, we argue that semantic annotations are a suitable tool to characterize sets of models. These characteristics improve model classification, allow to identify additional features for model retrieval tasks, and enable the comparison of sets of models.

O B I O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


the complex dynamics of collaborative tagging The debate within the Web community over the optimal means by which to organize information often pits formalized classifications against distributed collaborative tagging systems. A number of questions remain unanswered, however, regarding the nature of collaborative tagging systems including whether coherent categorization schemes can emerge from unsupervised tagging by users. This paper uses data from the social bookmarking site delicio. us to examine the dynamics of collaborative tagging systems. In particular, we examine whether the distribution of the frequency of use of tags for "popular" sites with a long history (many tags and many users) can be described by a power law distribution, often characteristic of what are considered complex systems. We produce a generative model of collaborative tagging in order to understand the basic dynamics behind tagging, including how a power law distribution of tags could arise. We empirically examine the tagging history of sites in order to determine how this distribution arises over time and to determine the patterns prior to a stable distribution. Lastly, by focusing on the high-frequency tags of a site where the distribution of tags is a stabilized power law, we show how tag co-occurrence networks for a sample domain of tags can be used to analyze the meaning of particular tags given their relationship to other tags.

O O O O O B O O O O B O O O O O O O O O O O O O O O B O B B O O O O O O O O O O O O B B O O O O O O O O O B O B O B O B O O O O O O O O O O O O O B B O O O O O O O O O O O B O B O O O O O O O O B O O B O O O O O O O O O O O O O O B I O O O O O O O B O B O O O O O O B O O O O O O O B O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O B O O O O O B

order
use
web
paper
complex systems
systems
users
tags
data
tagging
distributed

network
social bookmark
power laws
communities
timing
sampling
informal
delicious
coherence
pattern
classification
emergent semantics
organization
relationships
histories
optimality
dynamic
mean
generation model
categorical
complexity
collaborative filtering
collaborative tagging
scheme


Software for evaluating sediment-induced stratification in open-channel flows Open channel flow containing sediment suspension subjects itself to a density gradient in the vertical direction, i.e. density self-stratification, due to the tendency for suspended sediment to settle. Velocity and concentration profiles under the effect of density stratification may differ significantly from the conventional logarithmic and Rousean distributions associated with open channel flow. It is hence important to include this effect into flow computations in order to accurately predict flow characteristics such as the resistance coefficient, near-bed sediment concentration, flow and sediment discharge. In this study we introduce a software, StratSedOC, for such purpose. The application contains a user-friendly interface which allows users to evaluate and visualize the differences in the velocity, concentration and eddy viscosity profiles when stratification effects are taken into account. In addition to the standard logarithmic/Rousean formulation, the model uses three turbulence closures, i.e. an algebraic model (SmithMcLean) and two differential models (k-? and MellorYamada). The software application can also be used to study the effect of sediment mixtures on flow stratification under different boundary conditions for near-bed sediment concentration. Comparison among the model and experimental results suggests that the MellorYamada model predicts a damping effect on the eddy viscosity which is similar to the SmithMcLean model, while the k-? model consistently predicts weaker stratification effects. Based on this result, a modified boundary condition for the k-? model is then proposed.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

rans model
velocity profile
concentration profile
modified k-?
user-friendly model


A note on the emptiness problem for alternating finite-memory automata We present alternative relatively simple and self-contained proofs of decidability of the emptiness problems for one-register alternating finite-memory automata and one-register alternating finite-memory tree automata.

O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

infinite alphabets
alternating finite-memory automata
alternating finite-memory tree automata


The ordinal consistency of a fuzzy preference relation In this paper, we first analyze the rationality of weak transitivity of a fuzzy preference relation defined by Tanino [Fuzzy preference orderings in group decision making, Fuzzy Sets and Systems 12 (1984) 117131]. We then propose a revised definition of weak transitivity (we call it ordinal consistency). We propose the ordinal consistency index (OCI) to measure the degree of ordinal consistency of a fuzzy preference relation, which is to count the unreasonable 3-cycles in a directed graph that represents the fuzzy preference relation. Afterwards, a procedure to compute the order consistency index and to locate each cycle, as well as to find the inconsistent judgments in the fuzzy preference relation is proposed. In order to repair the inconsistency of a fuzzy preference relation, an algorithm is developed to find and remove 3-cycles in the graph. The algorithm eliminates 3-cycles in a graph more effectively and the proposed method for improving consistency method aims to preserve the initial preference information of the decision maker. Furthermore, the method can be used not only for a strict fuzzy preference relation, but also for non-strict fuzzy preference relation. Finally, we provide some examples to show the effectiveness and validity of the proposed method.

O B I O O B I I O O O O O O O B O B I O O B I I O O O O O O O O O O O O O O O O O O O O O O O O B I O O O B I O O O B I O O O O O O O B I O O B I I O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O B O O O O O O O O O O B I I O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O B I I O O O O O O O O O O O O O O O

ordinal consistency
fuzzy preference relation
rationality
cycle
weak transitivity


Subsethood, entropy, and cardinality for interval-valued fuzzy sets - An algebraic derivation In this paper a unified formulation of subsethood, entropy, and cardinality for interval-valued fuzzy sets (IVFSs) is presented. An axiomatic skeleton for subsethood measures in the interval-valued fuzzy setting is proposed, in order for subsethood to reduce to an entropy measure. By exploiting the equivalence between the structures of IVFSs and Atanassov's intuitionistic fuzzy sets (A-IFSs), the notion of average possible cardinality is presented and its connection to least and biggest cardinalities, proposed in [E. Szmidt, J. Kacprzyk, Entropy for intuitionistic fuzzy sets, Fuzzy Sets and Systems 118 (2001) 467-477], is established both algebraically and geometrically. A relation with the cardinality of fuzzy sets (FSs) is also demonstrated. Moreover, the entropy-subsethood and interval-valued fuzzy entropy theorems are stated and algebraically proved, which generalize the work of Kosko [Fuzzy entropy and conditioning, Inform. Sci. 40(2) (1986) 165-174; Fuzziness vs. probability, International Journal of General Systems 17(2-3) (1990) 211-240; Neural Networks and Fuzzy Systems, Prentice-Hall International, Englewood Cliffs, NJ, 1992; Intuitionistic Fuzzy Sets: Theory and Applications, Vol. 35 of Studies in Fuzziness and Soft Computing, Physica-Verlag, Heidelberg, 19991 for FSs. Finally, connections of the proposed subsethood and entropy measures for IVFSs with corresponding definitions for FSs and A-IFSs are provided. (c) 2007 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

subsethood measures
average possible cardinality

interval-valued fuzzy sets
atanassov's intuitionistic fuzzy sets
entropy-subsethood theorem
interval-valued fuzzy entropy theorem


Image processing of outer-product matrices - A new way to classify samples - Examples using visible/NIR/MIR spectral data A chemometric analysis has been developed to emphasise the discrimination power of spectroscopic techniques such as near infrared, mid-infrared and visible spectroscopy. The combination of two spectral domains using outer product analysis (OPA) leads to the calculation of an outer product (OP) matrix. The representation of this matrix is called the "analytical fingerprint" of the samples and their classification is performed in the following steps. First, two different techniques are tested by subtracting the images one-by-one and the sum of all the elements of the resulting difference matrix gives a scalar, characteristic of the distance between the two images. Combining chemical analysis with image, processing techniques provides an original approach to study butters and margarines in relation to their fat content. Best results were obtained with the OP matrix built from NIR and visible signals following the use of city-block distance and average linkage. Samples were arranged in four groups: 100%, 82-75%, 70-59% and 38-25% w/w fat. The cophenetic correlation coefficient (validity of the cluster information generated by the linkage function) associated with these spectral data has a value of 0.973. Similar results were obtained using Ward's algorithm which generated four groups and a cophenetic correlation coefficient equal to 0.959. (c) 2006 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

infrared spectroscopy
hierarchical classification ascendant
food analysis
chemometrics


Database intrusion detection using sequence alignment Information is considered to be the most valuable asset of any organization and hence, it should be securely maintained. However, rapid proliferation of the Internet and Web applications has increased the threat of information security breaches. Traditional database security mechanisms are often not sufficient to protect sensitive information against novel attacks. Intrusion detection systems (IDS) are used to detect any such intrusion, once traditional security mechanisms have been compromised. User-level profile is effective for database intrusion detection, but maintaining such profiles is not practical for an organization with a large number of users. Thus, an IDS needs to be flexible enough to choose a profile granularity according to the type of the organization. Further, only intra-transactional pattern matching for intrusion detection is not quite effective for detecting intrusion in a database. We propose an IDS that uses inter-transactional as well as intra-transactional features for intrusion detection. It supports selection of profile and transactional feature granularity as well. We use sequence alignment as a tool for comparing database access patterns of genuine users and intruders.

B I O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O

blast
transaction granularity
query type


A simulation model for AGC studies of hydrohydro systems AGC studies pertaining to hydrohydro systems have received little attention. In this paper a simulation model for AGC studies of such systems has been proposed. The difficulty in extending the traditional approach [Elgerd OI. Electric energy systems theory. New York: Mc-Graw Hill; 1983.] for such systems is overcome by assuming that all areas in a system operate at the same frequency. The proposed simulation model is obtained by ignoring the difference in frequency between control areas, unlike the traditional approach, where in each area is assumed to operate at a different frequency. The features of the proposed model have been demonstrated through simulation studies.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

automatic generation control
simulation models
hydro systems


Bayesian inference using record values from Rayleigh model with application In this article, based on a set of upper record values from a Rayleigh distribution, Bayesian and non-Bayesian approaches have been used to obtain the estimators of the parameter, and some lifetime parameters such as the reliability and hazard functions. Bayes estimators have been developed under symmetric (squared error) and asymmetric (LINEX and general entropy (GE)) loss functions. These estimators are derived using the informative and non-informative prior distributions for ?. We compare the performance of the presented Bayes estimators with known, non-Bayesian, estimators such as the maximum likelihood (ML) and the best linear unbiased (BLU) estimators. We show that Bayes estimators under the asymmetric loss functions are superior to both the ML and BLU estimators. The highest posterior density (HPD) intervals for the Rayleigh parameter and its reliability and hazard functions are presented. Also, Bayesian prediction intervals of the future record values are obtained and discussed. Finally, practical examples using real record values are given to illustrate the application of the results.

O O O B I O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O B I O O O O O O O O O

highest posterior density (hpd) intervals


A type-safe embedding of SQL into Java using the extensible compiler framework J% The SQL queries are syntactically checked. Optionally the SQL queries can be validated against a specified SQL database schema. Each SQL query can be separately configured with different compile-time features. The integration between the Java and SQL is type-safe. The compiler automatically generates secure code against SQL injection attacks.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

domain-specific languages
programming languages


Algorithms for ad hoc and sensor networks Wireless and mobiles networks are excellent playground for researchers with an algorithm background. Many research problem turn out to be variants of classic graph theory problems. In-particular the rapidly growing areas for ad hoc and sensor networks demand new solutions for timeless graph theory problems, because: (i) wireless devices have lower bandwidth and (ii) wireless devices are mobile and therefore the topology of the network changes rather frequently. As a consequences, algorithms for wireless and mobile networks should have: (i) as little communication as possible and should (ii) run as fast as possible. Both goals can only be achieved by developing algorithms requiring a small number of communication rounds only (so-called local algorithm). In the work we present a few algorithmic applications in wireless networking, such as clustering, topology control and geo-routing. Each section is supplemented with an open problem. (c) 2005 Elsevier B.V. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B B I O O O O O O O O O O O O O O O O O

interference
dominating sets
geo-routing


Automatic processing of handwritten bank cheque images: a survey Bank cheques (checks) are still widely used all over the world for financial transactions. Huge volumes of handwritten bank cheques are processed manually every day in developing countries. In such a manual verification, user written information including date, signature, legal and courtesy amounts present on each cheque has to be visually verified. As many countries use cheque truncation systems (CTS) nowadays, much time, effort and money can be saved if this entire process of recognition, verification and data entry is done automatically using images of cheques. An attempt is made in this paper to present the state of the art in automatic processing of handwritten cheque images. It discusses the important results reported so far in preprocessing, extraction, recognition and verification of handwritten fields on bank cheques and highlights the positive directions of research till date. The paper has a comprehensive bibliography of many references as a support for researchers working in the field of automatic bank cheque processing. The paper also contains some information about the products available in the market for automatic cheque processing. To the best of our knowledge, there is no survey in the area of automatic cheque processing, and there is a need of such a survey to know the state of the art.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

bank check processing
courtesy amount recognition
legal amount recognition
date recognition
signature verification


Ab

initio

and

DFT

study

of

the

inner

mechanism

and

dynamic

stereochemistry

of

electrophilic

addition

reaction

of

bromine

to

The

inner

mechanism

and

dynamic

stereochemistry

of

electrophilic

addition

of

bromine

to

bisbenzotetracyclo[6.2.2.2(3,6).0(2,7)]tetradeca-4,9,11,13-tetraene(BBTT)

molecule

have

been

investigated

by

the

methods

of

quantum

chemistry.

The

structure

of

the

BBTT

molecule

has

been

studied

by

ab

initio

and

methods

using

the

and

basis

sets.

The

double

bonds

of

BBTT

molecule

are

endo-pyramidalized.

The

structure

and

stability

of

the

cationic

intermediates

and

products

of

the

addition

reaction

have

been

investigated

by

and

methods.

The

bridged

bromonium

cation

isomerized

into

the

more

stable

nonclassical

delocalized

N-

and

U-type

cations

and

the

difference

between

the

stability

of

these

cations

is

small.

For

the

determination

of

the

direction

of

addition

reaction

and

the

stereochemistry

of

the

products,

the

stability

of

nonclassical

delocalized

N-

and

U-type

ions

and

the

structure

of

their

cationic

centres

play

a

vital

role.

Since

the

cationic

centre

of

the

N-type

ion

is

in

interaction

with

the

benzene

ring

from

the

exo

face,

the

nucleofilic

attackof

the

bromide

anion

to

this

centre

occurs

from

the

endo

face

and

the

exo,endo-isomer

of

the

N-type

product

is

obtained.

The

attack

of

bromide

anion,

towards

the

cationic

centre

of

U-type

ion

from

the

endo

face

is

sterically

hindered

by

the

hydrogen

atom

therefore

the

attack

occurs

from

the

exo

face,

which

interacts

with

the

benzene

ring

and

the

more

stable

exo,exo-isomer

of

U-type

product

is

formed.

Although,

the

U-type

cation

was

kcal

more

stable

than

the

N-type

cation,

the

U-type

product

was

kcal

less

stable

than

the

N-type

product.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Independent testing for assessing the calibration of the HargreavesSamani equation: New heuristic alternatives for Iran We modeled evapotranspiration using temperature based approaches. HargreavesSamani was compared with GEP models. Locally trained models gave the superior results. Externally trained GEP is a good alternative to locally trained model.

O O O O O B O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O


QoS for real-time reliable multicasting in wireless multi-hop networks using a Generation-Based Network Coding Most of the works on Generation-Based Network Coding (GBNC) consider a fixed generation size. A large generation size maximizes the Network Coding benefits but leads to a long delay while a small generation size reduces the delay but decreases the throughput. This paper presents the DYnamic GEneration Size (DYGES) approach. Our network-aware method adjusts the generation size according to the network variations (network size, congestion, losses) for multicast flows to keep the delay steady. Since Network Coding and redundancy cope with data packet loss, we propose an enhancement of DYGES with ACK recovery. This method, named RDYGES, uses the opportunistic listening feature of nodes to recover the lost ACK. Our goal is to guarantee a Quality of Service (QoS) in terms of delay. The simulation results show the accuracy of our approach.

O O O O O O O O O O O O B I O O O O O O B I O O O O B O O O B O O O B I O O O O O O O O O O B O O O O O O O O O O O O O B O O O O O O O O B O O O O O O O O O O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O

network coding
generation
multicast
quality of service


Second-order nonlinear impulsive integro-differential equations of mixed type with time-varying generating operators and optimal controls on Banach spaces In this paper, a class of second-order nonlinear impulsive integro-differential equations of mixed type whose principle is time-varying generating operators with unbounded perturbation on Banach spaces is considered. Discussing the perturbation of time-varying operator matrix and constructing corresponding the evolution system generated by operator matrix. we introduce the reasonable mild solution of second-order nonlinear impulsive integro-differential equations of mixed type and prove the existence of mild solutions. The existence of optimal controls for a Lagrange problem of systems governed by the second-order nonlinear impulsive integro-equations of mixed type is also presented. An example is given for demonstration. Crown Copyright (c) 2008 Published by Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

unbounded time-varying operator matrix
integral operator of mixed type
compactness
optimal control


An efficient approach to an automatic detection of erythemato-squamous diseases This paper presents a novel approach to automatic detection of the erythemato-squamous diseases based on fuzzy extreme learning machine (FELM). Enormous computational efforts are required to classify these erythemato-squamous diseases. Some of the approaches performed previously are through fuzzy logic, artificial neural networks and neuro-fuzzy models. FELM-based differential diagnosis of these diseases involves decisions made by fuzzy logic and extreme learning machine (ELM) with greater efficiency in both time and accuracy. In this paper, we develop a user-friendly interface and this tool will be useful for a dermatologist to estimate the six types of erythemato-squamous diseases with the help of patients histopathological and clinical data. Then, the developed interface is derived inbuilt using neural networks, adaptive neuro-fuzzy inference system and FELM. A dataset containing records of 366 patients with 34 features that define six disease characteristics was taken, of which 310 records were used as training data and 56 other records used as testing data. The dataset was preprocessed to obtain fuzzy values as input to get more accurate results in FELM. Given a training set of such records, ELM approach is applied. By combining fuzzy logic and ELM, more accurate results with increased performance are obtained with less computational efforts. Finally, the proposed FELM model proves to be a potential solution for the diagnosis of erythemato-squamous diseases with significant improvement in computational time and accuracy compared with other models discussed in the recent literature.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B I B I I O O O O O O O O O O O O O B I O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B O O O O O B I O B O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

felm
fuzzy logic
elm
artificial neural networks


development of modern curriculum in information systems at master level The aim of the paper is to discuss the body of knowledge, which should be provided by modern curriculum in information systems at master level, and techniques used in development of such curricula. The ideas presented in this paper are based on the experience gained in the project MOCURIS. The curriculum developed in this project takes into account integration trends in European area as well as the transformation of industrial economics into knowledge-based digital economics.

O O O B I I I O O O O O O O O O O O O O O O O O O O O O B I I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

systems engineering
curriculum engineering
mocuris project
study program


Political determinants of e-government performance revisited: Comparing democracies and autocracies I explore the nexus between e-government research and comparative political science. Statistical analysis of the UN E-Government Index editions from 2003 to 2014 Discussion of theoretical and methodological shortcomings in previous studies Autocracies have caught up with democracies in e-government performance. E-government as a politically neutral instrument can enhance autocratic legitimacy.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

comparative politics
e-government
regime type
democracy
autocracy


IT-based touch panel cognition and development for the visually impaired: an experimental study in Taiwan In order to understand the cognition of Taiwanese visually impaired people who use an IT-based touch panel, a prototype named the Chinese Braille Simulator is developed. This prototype uses braille simulation software, speech synthesis and a touch panel to allow people with impaired vision to send and receive short messages. The TAM and content analysis are used, and our findings show that visually impaired people find the IT-based touch panel both interesting and useful. We conclude that current technology developers should focus on a braille interface in IT-based touch panels for the visually impaired. Short-, mid- and long-term recommendations for practitioners are also made.

O B I B O O O O O O O O O O O O O O O O B O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


A DSS generator for multiobjective optimisation of spreadsheet-based models Water management practice has benefited from the development of model-driven Decision Support Systems (DSS), and in particular those that combine simulation with single or multiple-objective optimisation tools. However, there are many performance, acceptance and adoption problems with these decision support tools caused mainly by misunderstandings between the communities of system developers and users. This paper presents a general-purpose decision-support system generator, GANetXL, for developing specific applications that require multiobjective optimisation of spreadsheet-based models. The system is developed as an Excel add-in that provides easy access to evolutionary multiobjective optimisation algorithms to non-specialists by incorporating an intuitive interactive graphical user interface that allows easy creation of specific decision-support applications. GANetXLs utility is demonstrated on two examples from water engineering practice, a simple water supply reservoir operation model with two objectives and a large combinatorial optimisation problem of pump scheduling in water distribution systems. The two examples show how GANetXL goes a long way toward closing the gap between the achievements in optimisation technology and the successful use of DSS in practice.

O O O O B O O O O B I O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

decision support systems
multiobjective
water management

optimization
evolutionary algorithms
pareto solutions
spreadsheet models


Monte Carlo simulations of the transport of sputtered particles Program SPATS models the transport of neutral particles during magnetron sputtering deposition. The 3D Monte Carlo simulation provides information about spatial distribution of the fluxes, density of the sputtered particles in the chamber glow discharge area, and kinetic energy distribution of the arrival flux. Collision events are modelled by scattering in Biersack's potential, Lennard-Jones potential, or by binary hard sphere collision approximation, The code has an interface for Monte Carlo TRIM simulated results of the sputtered particles. (C) 1999 Elsevier Science B.V. All rights reserved.

B I O O O O O O O O O O O O O O O O B I B O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O

monte carlo
magnetron sputtering
deposition


A Novel Data Hiding Method for Grayscale Images Based on Pixel-Value Differencing and Modulus Function The purpose of this paper is to present a novel data hiding technique which is based on pixel-value differencing and modulus function and is capable of reducing the distortion of stego image for graylevel image. In the proposed scheme, we take two close pixels as a block to hide secret data where the payload of each block is determined by pixel-value. differencing. In order to obtain a better stego-image quality, we hide more data into the blocks with the higher difference value than that the blocks with the smaller difference value. In data embedding procedure, we propose a novel technique which is capable of reducing the distortion of stego image with the minimal. In our new scheme, we adopt the non-decimal number system to represent the secret data, and utilize the modulus function to minimize the possible distortion after hiding data. Since there are six degrees of payload are used in our method, we present the revision method to ensure the consistency of degree for each block. Therefore, the proposed scheme is blind because the original image is unnecessary in the data extraction. The experimental results demonstrate that the proposed scheme is greatly reducing distortion and its performance is better than that of those existing schemes.

O O B I O O O O O O O O O B I O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Panel generation framework for seakeeping analysis of multiple bodies and offshore structures This paper presents a panel generation framework for seakeeping analysis of multiple bodies and offshore structures. The configurations of multiple bodies and offshore structures are different from those of a single ship. In particular, the topological structure of the free surfaces becomes complicated due to the multiple floating bodies, resulting in multiple classifications for the free surfaces based on their genus. The multi-body configuration consists of two floating bodies placed in two configurations, i.e., side by side and tandem, which would generate two holes in the free surface. For the offshore structure case, multiple holes are generated in the free-surface domain due to the legs of the offshore structure. In this work, strategies for generating body and free-surface panels are provided, and the results are analyzed. A software prototype that implements the proposed methods is developed to provide efficient panel generation for multiple bodies and offshore structures. Examples demonstrate that the proposed framework can be successfully used for seakeeping analysis of multiple bodies and offshore structures.

B I O O B B O O O O O O O O O O B I O O B B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O B B O O O O O O

offshore structure
panel generation
seakeeping
analysis


Transactional distance in an undergraduate project-based systems modeling course Assessing the level and quality of collaboration between students working in project teams is a complex task. The main goal of our study was to develop and validate an online questionnaire for assessing the quality of distance teamwork collaboration in a project-based systems modeling course. The research goals included assessing the transactional distance (TD) perceptions among peer students who had collaborated in jointly constructing conceptual system models of projects carried out by distant researchers and the TD between the students on one hand and the distant researchers on the other hand. The research questions were aimed at validating the TD questionnaire as a tool for assessing TD. The research population included undergraduate students who participated and collaborated via a visualization-based environment as part of the EU VISIONAIR infrastructure project. The students interacted both among themselves and with remote researchers across Europe. Reliability and inter-correlation tests have indicated internal structure validity and reliability of the TD questionnaire. Correlation with other student outcomes indicated content validity by criterion. Experiencing visualization-based environments was a key factor in student satisfaction. Based on our findings and the collaboration literature, TD may serve as an alternative assessment tool for evaluating the quality of collaboration among peer students and researchers.

B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

project-based learning
systems engineering
object process methodology (opm)
engineering education
collaborative learning
visualization
conceptual modeling


Computing the minimum number of hybridization events for a consistent evolutionary history ? It is now well-documented that the structure of evolutionary relationships between a set of present-day species is not necessarily tree-like. The reason for this is that reticulation events such as hybridizations mean that species are a mixture of genes from different ancestors. Since such events are relatively rare, a fundamental problem for biologists is to determine the smallest number of hybridization events required to explain a given (input) set of data in a single (hybrid) phylogeny. The main results of this paper show that computing this smallest number is APX-hard, and thus NP-hard, in the case the input is a collection of phylogenetic trees on sets of present-day species. This answers a problem which was raised at a recent conference (Phylogenetic Combinatorics and Applications, Uppsala University, 2004). As a consequence of these results, we also correct a previously published NP-hardness proof in the case the input is a collection of binary sequences, where each sequence represents the attributes of a particular present-day species. The APX-hardness of these problems means that it is unlikely that there is an efficient algorithm for either computing the result exactly or approximating it to any arbitrary degree of accuracy.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


The lattice Boltzmann method in bioreactor design and simulation The lattice Boltzmann method (LBM) for fluid flow has already proven itself a viable alternative to classical CFD (computational fluid dynamics) methods based on discrete scheme application to Navier Stokes equations governing the fluid flow. In this paper, we aim to verify the applicability of the LBM in a special case of a Couette-Taylor photobioreactor-a device comprised of two coaxial cylinders with a rotating inner wall. An appropriate numerical approach to the curved moving wall boundary condition is presented and verified by velocity flow field comparison with analytical solution. The parallelism potential of the LBM is exploited on the parallel platform of CUDA (Compute Unified Device Architecture). Microalgae growth in the flow field simulated by the LBM is based on the photosynthetic factory (PSF) model treated in a parallel stochastic manner and implemented also on the parallel platform of CUDA. The parallel stochastic PSF solver has been validated by comparison with an analytical solution of the PSF model at constant irradiance. (C) 2011 Elsevier Ltd. All rights reserved.

O B I I O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O

lattice boltzmann method
photosynthetic factory


Cooperative control of a human and a robot manipulator for positioning a cart on a frictionless plane Robots may be expected to execute some tasks in cooperation with humans. Control systems for such robots should be appropriate to adapt to human characteristics in order to successfully accomplish the task. Pushing a cart on a frictionless plane in cooperation with a human is a basic example to such a task. To control the motion of an object from one point to another on a frictionless plane is impossible by only pushing in one direction without supporting it in the opposite direction, since as soon as the force is applied, the object will move without stopping its motion. In this paper, compliant cooperative positioning of a cart on a frictionless plane by a human and a manipulator is proposed using impedance control method with the parameters obtained from human-human cooperation. (C) 2006 Elsevier Ltd. All rights reserved.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O

cooperative positioning
impedance control