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This work reports a Finite Element Analysis (FEA) model study of the stator current spectra of a commercial permanent magnet (PM) AC machine operating with rotor PM demagnetisation faults. A range of PM uniform and local demagnetisation fault scenarios at different severity conditions are examined. The aim of this study is to investigate the extent to which different modes of PM demagnetisation could be distinguished by inspecting the spectral signature patterns these generate in the stator current signal. To this end, a generalised mathematical characterisation of PM fault spectral signature in the stator current is examined and a 2-D FEA software used to establish a model of the studied PM machine design. The FEA model was employed to predict the current signal spectral signature patterns of a range of different PM demagnetisation faults. These are then correlated with those arising from the derived expressions to examine whether the predicted and expected spectral trends are in agreement and whether their observation as the potential to provide diagnostic information.

BackgroundWhile the role of acute non-invasive ventilation (NIV) has been shown to improve outcome in acute life-threatening hypercapnic respiratory failure in COPD, the evidence of clinical efficacy of long-term home NIV (LTH-NIV) for management of COPD is less. This document provides evidence-based recommendations for the clinical application of LTH-NIV in chronic hypercapnic COPD patients.Materials and methodsThe European Respiratory Society task force committee was composed of clinicians, methodologists and experts in the field of LTH-NIV. The committee developed recommendations based on the GRADE (Grading, Recommendation, Assessment, Development and Evaluation) methodology. The GRADE Evidence to Decision framework was used to formulate recommendations. A number of topics were addressed under a narrative format which provides a useful context for clinicians and patients.ResultsThe task force committee delivered conditional recommendations for four actionable PICO (target population-intervention-comparator-outcome) questions, 1) suggesting for the use of LTH-NIV in stable hypercapnic COPD; 2) suggesting for the use of LTH-NIV in COPD patients following a COPD exacerbation requiring acute NIV 3) suggesting for the use of NIV settings targeting a reduction in carbon dioxide and 4) suggesting for using fixed pressure support as first choice ventilator mode.ConclusionsManaging hypercapnia may be an important intervention for improving the health outcome of COPD patients with chronic respiratory failure. The task force conditionally supports the application of LTH-NIV to improve health outcome by targeting a reduction in carbon dioxide in COPD patients with persistent hypercapnic respiratory failure. These recommendations should be applied in clinical practice by practitioners that routinely care for chronic hypercapnic COPD patients.

Land consolidation is essential in China for improving land use efficiency and supporting rural public space governance. Previously, the implementation of land consolidation projects (LCPs) had been mainly led by governments in China. In recent years, the Chinese government vigorously promoted land consolidation, and land consolidation in the corporation-leading mode (CLM) has emerged. This study focused on investigating the performance of CLM projects and the difference in performance levels between the CLM projects and the government-leading mode (GLM) projects. Based on the improved extensible matter&ndash, element model, the performance levels of 14 LCPs in GLM and CLM of Jianghan Plain, Hubei Province and related impact factors were analyzed. A set of evaluation indices was selected based on the &ldquo, process-based thinking and logic&rdquo, Results showed that: (1) performance levels of the 14 LCPs are different, most of the projects in the GLM have ordinary or poor performance, while most of the projects in the CLM have excellent or good performance, (2) factors affecting the performance levels of LCPs are also different in the two modes. The main influencing factors in the CLM were the poor access to field roads, insufficient shelterbelt planting, and low land reclamation efficiency, while the insufficient shelterbelt planting, low annual output value of farmland and grain production capacity, low increase rate of agricultural labor production, and low land reclamation efficiency were the main influencing factors in the GLM, (3) comparative analysis of the two modes revealed that LCPs in the CLM have clear investment directions, high output benefits, and obvious advantages in the development of modern agriculture when compared with the GLM. To achieve improving the performance levels of LCPs, policy makers should actively innovate the implementation mode of LCPs and encourage all kinds of agricultural corporations to participate in land consolidation.

[EN] This paper presents a simulation tool designed for predicting the wear pattern on the running surface of the rails and for studying the evolution of rail corrugation after thousands of wheelset passages. This simulation tool implements a cyclic track model, a rotating flexible wheelset model, a wheel-rail contact model and a wear model. The vehicle-track system is modelled by using a substructuring technique, by which the vehicle, the rails and the sleepers are treated independently of each other and are coupled by the forces transmitted through the wheel-rail contact and the railpad. The vehicle model takes only account of the wheelset since the sprung masses of the vehicle are not relevant in the frequency range analysed. The wheelset model considers the flexibility of the wheelset and the effects associated with rotation. By using the Campbell diagram, two cases have been identified in which the combined effect of two different modes may give rise to higher wheel-rail contact forces and wear. © 2011 Taylor & Francis., The authors gratefully acknowledge the support for this work provided by the Project TRA2010-15669 (Ministerio de Ciencia e Innovacion) and the valuable help of P. Torstensson from Chalmers University, who suggested the use of the Campbell diagram in this investigation.

Non-contact removal of oral biofilms offers advantages beyond the reach of bristles, but it is unknown how energy transfer for removal from brush-to-biofilm occurs. In the present study we evaluated non-contact, oral biofilm removal by oscillating-rotating and sonic toothbrushes, and their acoustic output up to 6 mm distance. Whereas some brushes removed biofilm when used at a distance of up to 6 mm, others lost efficacy at a distance of 2-4 mm from the biofilm. Loss of efficacy was accompanied with high standard deviations and volumetric biofilm expansion. Both sonic and oscillating-rotating brushes caused fluid flows and the inclusion of air-bubbles, while non-contact acoustic energy-transfer was demonstrated to decay with distance for both types of brushes. We put forward the following mechanism for non-contact removal: (i) brush energy is absorbed by biofilm, resulting in the visco-elastic expansion of the biofilm; (ii) if the energy absorbed is sufficient and deformation is beyond the yield point, biofilm removal occurs; and (iii) if deformation is in the plastic range but below the yield point (i.e. at the limiting distance for non-contact removal), biofilm is expanded but not removed.

International expansion by retail banks can involve different modes of foreign entry, the most common being acquisitions, start-ups and joint ventures. But there is only limited consensus over which represents the best option, and banks choose the same or different modes when entering different countries. This article investigates the question of how managers make these choices by testing a mode selection model based on the perceptions of managers involved in 124 foreign market entries. The model considers their control and resource objectives, their willingness to trade off control for access local resources and the constraints on their entry: levels of local regulation, home/host country differences and entrants' resources. The results show that internationalizing banks choices of entry mode are influenced by managers' desire for control over their foreign ventures and by their local market resource requirements, as well as by foreign regulatory constraints and the differences between home and foreign markets - but not by entrant's size. Identifying the factors influencing banks' entry mode choices allows us to point out a number of key factors managers should take into account when planning their internationalization strategies.

The goods movement via terminals at ports is a complex operation as it involves use of different modes of transport that includes surface and marine. In this paper, we present three simulation models which can be used to understand and evaluate these operations. The macroscopic simulation model simulates the flows in and out of terminals and ports and it is integrated with a microscopic simulation model of the adjacent road network. A terminal cost model receives inputs from these two models to evaluate the cost associated with the processing of containers inside the terminal. The use of the three models is demonstrated by evaluating the impact of terrorist attack scenarios on a container terminal in LA/LB Port complex. © 2009 IFAC. 129 134 Sponsors: IFAC Technical Committee on Transportation Systems TC 7.4 Conference code: 85831 Cited By :2

The presence and maturity of the salivary pellicle influences microbial adhesion and its tenacity in the oral cavity, posing a challenge to different plaque-control systems. Some plaque-control systems rely on surface-tension forces arising from passing microbubbles sprayed over the pellicle. Passage of such bubbles is accompanied by a high fluid flow, but systematic studies are lacking on the contribution of fluid flow vs. microbubbles towards plaque removal. Therefore, the aim of this study was to determine the detachment efficacy of laminar fluid flow (wall shear rates 11,000-16,000 s(-1)), with and without microbubbles, towards the detachment of Actinomyces naeslundii T14V-J1 and Streptococcus oralis J22, and their coadhering aggregates, from salivary pellicles formed over 2 h or 16 h from reconstituted human whole saliva. Microbubbles in a fluid flow were more efficient at inducing single bacterial detachment, resulting in almost complete (97%) removal for S. oralis J22 and a 15-fold increase in A. naeslundii T14V-J1 removal as compared to the detachment caused by fluid flow alone. A. naeslundii was more difficult to remove and apparently formed the strongest bonds with high-molecular-weight proteins in 16-h pellicles. The detachment of coaggregates after 2 min left a substantial amount of adhered bacterial mass, including more than 60% of singly attached A. naeslundii on the pellicle surface, providing nucleation sites for the de novo adhesion of coadhering streptococci.

The presence and maturity of the salivary pellicle influences microbial adhesion and its tenacity in the oral cavity, posing a challenge to different plaque-control systems. Some plaque-control systems rely on surface-tension forces arising from passing microbubbles sprayed over the pellicle. Passage of such bubbles is accompanied by a high fluid flow, but systematic studies are lacking on the contribution of fluid flow vs. microbubbles towards plaque removal. Therefore, the aim of this study was to determine the detachment efficacy of laminar fluid flow (wall shear rates 11,000-16,000 s(-1)), with and without microbubbles, towards the detachment of Actinomyces naeslundii T14V-J1 and Streptococcus oralis J22, and their coadhering aggregates, from salivary pellicles formed over 2 h or 16 h from reconstituted human whole saliva. Microbubbles in a fluid flow were more efficient at inducing single bacterial detachment, resulting in almost complete (97%) removal for S. oralis J22 and a 15-fold increase in A. naeslundii T14V-J1 removal as compared to the detachment caused by fluid flow alone. A. naeslundii was more difficult to remove and apparently formed the strongest bonds with high-molecular-weight proteins in 16-h pellicles. The detachment of coaggregates after 2 min left a substantial amount of adhered bacterial mass, including more than 60% of singly attached A. naeslundii on the pellicle surface, providing nucleation sites for the de novo adhesion of coadhering streptococci.

With rapid advancements in sensing, networking, and computing technologies, recent years have witnessed the emergence of cyber-physical systems (CPS) in a broad range of application domains. CPS is a new class of engineered systems that features the integration of computation, communications, and control. In contrast to general-purpose computing systems, many cyber-physical applications are safety critical. These applications impose considerable requirements on quality of service (QoS) of the employed networking infrastruture. Since IEEE 802.15.4 has been widely considered as a suitable protocol for CPS over wireless sensor and actuator networks, it is of vital importance to evaluate its performance extensively. Serving for this purpose, this paper will analyze the performance of IEEE 802.15.4 standard operating in different modes respectively. Extensive simulations have been conducted to examine how network QoS will be impacted by some critical parameters. The results are presented and analyzed, which provide some useful insights for network parameter configuration and optimization for CPS design. © 2011 Feng Xia et al.

Non-contact removal of oral biofilms offers advantages beyond the reach of bristles, but it is unknown how energy transfer for removal from brush-to-biofilm occurs. In the present study we evaluated non-contact, oral biofilm removal by oscillating-rotating and sonic toothbrushes, and their acoustic output up to 6 mm distance. Whereas some brushes removed biofilm when used at a distance of up to 6 mm, others lost efficacy at a distance of 2-4 mm from the biofilm. Loss of efficacy was accompanied with high standard deviations and volumetric biofilm expansion. Both sonic and oscillating-rotating brushes caused fluid flows and the inclusion of air-bubbles, while non-contact acoustic energy-transfer was demonstrated to decay with distance for both types of brushes. We put forward the following mechanism for non-contact removal: (i) brush energy is absorbed by biofilm, resulting in the visco-elastic expansion of the biofilm; (ii) if the energy absorbed is sufficient and deformation is beyond the yield point, biofilm removal occurs; and (iii) if deformation is in the plastic range but below the yield point (i.e. at the limiting distance for non-contact removal), biofilm is expanded but not removed.

This paper deals with self-ignition of catalytic microburners from ambient cold-start conditions. First, reaction kinetics for hydrogen combustion is validated with experimental results from the literature, followed by validation of a simplified pseudo-2D microburner model. The model is then used to study the self-ignition behavior of lean hydrogen/air mixtures in a Platinum-catalyzed microburner. Hydrogen combustion on Pt is a very fast reaction. During cold start ignition, hydrogen conversion reaches 100% within the first few seconds and the reactor dynamics are governed by the " thermal inertia" of the microburner wall structure. The self-ignition property of hydrogen can be used to provide the energy required for propane ignition. Two different modes of hydrogen-assisted propane ignition are considered: co-feed mode, where the microburner inlet consists of premixed hydrogen/propane/air mixtures; and sequential feed mode, where the inlet feed is switched from hydrogen/air to propane/air mixtures after the microburner reaches propane ignition temperature. We show that hydrogen-assisted ignition is equivalent to selectively preheating the inlet section of the microburner. The time to reach steady state is lower at higher equivalence ratio, lower wall thermal conductivity, and higher inlet velocity for both the ignition modes. The ignition times and propane emissions are compared. Although the sequential feed mode requires slightly higher amount of hydrogen, the propane emissions are at least an order of magnitude lower than the other ignition modes. � 2010 The Combustion Institute.

A sequential extraction protocol has been used to determine the solid-phase partition of 210Po and 210Pb in anoxic marine sediment from the roads of Cherbourg (France) in the central English Channel. Measurements were also obtained in pore waters, in which 210Po activities range between 1 and 20 mBq L-1 and 210Pb activities between 2.4 and 3.8 mBq L-1, with highest activities in the topmost layer. These activities are higher than in seawater, suggesting that sediment act as a source of both 210Po and 210Pb for overlying water. The 210Po profile in the pore waters is apparently correlated with those obtained for Fe, Mn and SO42-, suggesting an influence of early diagenetic processes on the 210Po solid-liquid distribution. In the sediment, 210Po is predominantly bound to organic matter or chromium reducible sulphides, and residuals (clay minerals and refractory oxides). Our results indicate that 210Po is not significantly bound to AVS, i.e. acid volatile sulphides: bioturbation could play a role by the early redistribution of 210Po bound to acid volatile sulphides in the sediment. 210Po, 210Pb and Pb exhibit differences in terms of distribution, probably due to a different mode of penetration in the sediment. This work provides information on solid and liquid distribution of 210Po and 210Pb in marine sediment. These data are very scarce in the litterature. © 2009 Elsevier Ltd. All rights reserved.

For geothermal exploration and the development of enhanced geothermal systems (EGS) knowlegde of temperature at drillable depth is a prerequisite for site selection. Equally important is the thermo-mechanical signature of the lithosphere and crust which allow to obtain critical constraints for the crustal stress field and basement temperatures where borehole observations are rare. The stress and temperature field in Europe is subject to strong spatial variations which can be linked to polyphase extensional and compressional reactivation of the lithosphere, in different modes of deformation. In this paper we review key thermo-mechanical processes which influence the thermal state and the stress conditions in Europe. The development of innovative combinations of numerical and analogue modeling techniques is a key to thoroughly understand the spatial and temporal variations in crustal stress and temperature. For selected tectonic settings, marked by a specific deformation style, we discuss the relationship between key-factors in tectonic evolution and geothermal prospectivity. This relationship allows to approach in a rational fashion continent-scale exploration for geothermal resources and building hypothesis for thermal and mechanical characterization at depth. Further, through using deep subsurface lithosphere scale data and processes, the approach delivers valuable exploration constraints on the thermo-mechanical signature at deep depth levels and regions where near surface data is not reliable.

With the advent of more flexible discrete choice models, the analysis of heterogeneity at the observed and unobserved levels is receiving increasing attention. However, heterogeneity in decision rules has hardly been investigated in the mode choice context. This study proposes a heterogeneous decision rule model of mode choice incorporating utility maximization and disutility minimization using empirical data from Chennai City, India. The two decision rules may yield different estimates of mode choice probabilities if the error structure is not symmetric. Therefore, a heterogeneous decision rule model is estimated by postulating separate choice behaviors for each decision segment. Because the decision rule remains latent, individuals are probabilistically assigned to the two segments. The membership propensity of belonging to each class is modeled by using a binary logit form. The performance of the proposed heterogeneous decision rule (HDR) model is compared with the pure utility maximization, pure disutility minimization, and heterogeneous latent class models. The results reveal that the HDR model outperforms these alternative specifications. Further, significant differences are observed across the decision segments for aggregate modal shares, intrinsic preference for different modes, sensitivity to modal attributes, role of subjective factors, and the effect of activity patterns and accessibility. Factors influencing the decision-segment membership propensity are also identified. These findings have important behavioral and practical implications for analysis and evaluation of travel demand management measures aimed at sustainable urban transportation systems, congestion mitigation, and transit improvement.

It may happen that the equations governing the response of dynamical systems have some parameters whose values may not be known a priori and have to be obtained using parameter estimation schemes. In this article, we present a parameter estimation scheme for a class of sequential hybrid systems. By hybrid systems, we refer to those systems whose response is described by different governing equations corresponding to various regimes/modes of operation along with some criteria to switch between the same. In a sequential hybrid system, the different modes are arranged in a specific sequence and the system can switch from a given mode to either the previous mode or the following mode in this sequence. Here, we consider those systems whose governing equations consist of ordinary differential equations and algebraic equations. The conditions for switching between the various modes (referred to as transition conditions) are in the form of linear inequalities involving the system output. We shall first consider the case where the transition conditions are known completely. We present a parameter update scheme along with sufficient conditions that will guarantee bounded parameter estimation errors. Then, we shall consider the case where the transition conditions are not known in the sense that some parameters in these conditions are not known. We present a parameter estimation scheme for this case. We illustrate the performance of the parameter estimation scheme in both cases with some examples.

Date of Conference: 25-27 June 2007 Conference name: International Workshop on Content-Based Multimedia Indexing, 2007 The management and exchange of multimedia data is challenging due to the variety of formats, standards and intended applications. In addition, production of multimedia data is rapidly increasing due to the availability of off-the-shelf, modern digital devices that can be used by even inexperienced users. It is likely that this volume of information will only increase in the future. A key goal of the MUSCLE (Multimedia Understanding through Semantics, Computation and Learning) network is to develop tools, technologies and standards to facilitate the interoperability of multimedia content and support the exchange of such data. One approach for achieving this was the creation of a specific "E-Team", composed of the authors, to discuss core questions and practical issues based on the participant's individual work. In this paper, we present the relevant points of view with regards to sharing experiences and to extracting and integrating multimedia data and metadata from different modes (text, images, video). © 2007 IEEE.

For geothermal exploration and the development of enhanced geothermal systems (EGS) knowlegde of temperature at drillable depth is a prerequisite for site selection. Equally important is the thermo-mechanical signature of the lithosphere and crust which allow to obtain critical constraints for the crustal stress field and basement temperatures where borehole observations are rare. The stress and temperature field in Europe is subject to strong spatial variations which can be linked to polyphase extensional and compressional reactivation of the lithosphere, in different modes of deformation. In this paper we review key thermo-mechanical processes which influence the thermal state and the stress conditions in Europe. The development of innovative combinations of numerical and analogue modeling techniques is a key to thoroughly understand the spatial and temporal variations in crustal stress and temperature. For selected tectonic settings, marked by a specific deformation style, we discuss the relationship between key-factors in tectonic evolution and geothermal prospectivity. This relationship allows to approach in a rational fashion continent-scale exploration for geothermal resources and building hypothesis for thermal and mechanical characterization at depth. Further, through using deep subsurface lithosphere scale data and processes, the approach delivers valuable exploration constraints on the thermo-mechanical signature at deep depth levels and regions where near surface data is not reliable.