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Purpose of review To provide pieces of evidence and an overview of the pathophysiology of ventilator-induced lung injury (VILI) on subjects with noninjured lungs, and the intraoperative mechanical ventilation strategies to prevent VILI. Recent findings Numerous evidence has indicated that intraoperative mechanical ventilation is associated with an increased risk of postoperative pulmonary complications (PPCs) in patients with noninjured lungs. This risk is blamed for volutrauma, barotrauma, atelectrauma, and biotrauma, which are the primary mechanisms of ventilator-induced lung injury (VILI) during mechanical ventilation. VILI was worsened by a nonprotective ventilator setting using a high tidal volume (>10–12 ml/kg), a low level of positive end-expiratory pressure (PEEP

The symbol “moon” is the most important cultural and artistic code in Nguyễn Du’s The Tale of Kiều. It exists in various shapes with different characteristics depending on social and psychological circumstances, mainly through the character Thúy Kiều. Through our survey and analysis, the “moon” in Nguyễn Du’s The Tale of Kiều proves to have surpassed an ordinary natural image from the original text by Jin Yun Qiao [pseudonym of Qingxin Cairen (青心才人: Pure Heart Talented Man)]. The symbol is brimming with sentimental states and shades of life. More accurately, it pertains to physical and spiritual experiences in the secular world. First and foremost, we have discovered that through the subject of reflection and experience (Vương Thúy Kiều), the symbol “moon” is capable of expressing the deep layers of the subject’s ego. The specific goal of this article is to demonstrate the psychological and cultural implications of the “moon” by means of depicting its various manifestations in association with Thúy Kiều. However, it is necessary to place this analysis in general interrelations with other images and symbols in the text such as darkness, shades of the day, appearances of oil lamps, water element, the dream world, etc. All these components make up the negative space and the negative universe independent of the rest of the world. And the most important thing in these interrelations is the specific expression of the physical and spiritual states of the character Thúy Kiều. To reach our goals, we first focused on the text of the Tale of Kiều. Then, we referred to the related interdisciplinary theoretical views from Cultural Semiotics, Existential Phenomenology and Matter Psychoanalysis.

Computation offloading has emerged as one of the promising approaches to address the issues of restricted resources, leading to poor user experiences on smartphones in terms of battery life and performance when executing CPU intensive tasks. Meanwhile, an entire research domain has been initiated around this topic and several concepts have been studied touching both the smartphone and the cloud side. In this paper, we develop a categorization of fundamental aspects regarding computation offloading in heterogeneous cloud computing from the perspective of smartphone applications. We refer to heterogeneity in terms of the multitude of smartphone applications, the various uplink channels, and the variety of cloud solutions. We also survey state-of-the-art solutions for the identified categories. Finally, we conclude with a summary of the most important research challenges in making computation offloading reality.

African swine fever (ASF) is a devastating viral disease in pigs and is therefore economically important for the swine industry. ASF is characterized by a short incubation period and immediate death, making the early identification of ASF-infected pigs essential. This pilot-scale study evaluates whether the infrared thermography (IRT) technique can be used as a diagnostic tool to detect changes in skin temperature (Tsk) during the early stages of disease development in experimentally ASF-infected pigs. Clinical symptoms and rectal temperatures (Tcore) were recorded daily, and IRT readings during the experimental ASF infection were analyzed. All infected pigs died at 5–8 days post inoculation (dpi), and the incubation period was approximately 4 dpi. The average Tcore increased from 0 dpi (38.9 ± 0.3 °C) to 7 dpi (41.0 ± 0.5 °C) and decreased by 8 dpi (39.8 ± 0 °C). The maximum Tsk of ASF-infected pigs increased from 2 (35.0 °C) to 3 dpi (38.5 °C). The mean maximum Tsk observed from three regions on the skin (ear, inguinal, and neck) significantly increased from 2 to 3 dpi. This study presents a non-contact method for the early detection of ASF in infected pigs using thermal imaging at 3 days after ASF infection.

International audience; An enhanced multi-fiber beam-column element suitable for the analysis of reinforced concrete members including the torsional effect is presented in this paper. The model is developed based on displacement formulation with the assumptions of small displacement. The section kinematics is based on the assumptions of a two-node Timoshenko beam and enhanced by introducing additional degrees of freedom at each section in order to take into account the warping phenomenon. For this, a system of fixed points is created and interpolated by Lagrange functions and polynomials. To take into account the effect of stirrups, a discretization of control sections into regions following its material response is applied. The basic assumption of the modified compression field theory with a secant-stiffness formulation is used to represent the constitutive material model for reinforced concrete. The model is validated by comparison with analytical solutions and several experimental tests. The simulations include a variety of monotonic load conditions under bending, shear and torsion for specimens with rectangular sections.

Text coherence is an important factor that often gets overlooked by novice writers. Incoherence in academic writing directly affects both the reading experience and the comprehensibility of the articles. This paper introduces and describes a method for detecting incoherence in academic writing. The method utilized a fine-tuned BERT model in conjunction with a graph clustering algorithm. We benchmarked the method against baseline models on Discordant Sentence Detection using Time-travel dataset, and the results showed that the proposed method outperformed baseline models in terms of F1-score. Afterwards, the method was tested on corpora of Russian and English scientific articles in order to assess its proficiency in Narrative Incoherence Detection when applied to the paper's main research subject: academic writing. The paper's proposed method achieved a decent F1 of over 0.65 in Discordant Sentence Detection. For future work, our biggest goal is to further refine the method and be able to effectively deploy it on existing systems for reviewing academic corpora

Background Pneumoperitoneum and Trendelenburg position in laparoscopic surgeries could contribute to postoperative pulmonary dysfunction. In recent years, intraoperative lung-protective mechanical ventilation (LPV) has been reportedly able to attenuate ventilator-induced lung injuries (VILI). Our objectives were to test the hypothesis that LPV could improve intraoperative oxygenation function, pulmonary mechanics and early postoperative atelectasis in laparoscopic surgeries. Methods In this randomized controlled clinical trial, 62 patients indicated for elective abdominal laparoscopic surgeries with an expected duration of greater than 2 h were randomly assigned to receive either lung-protective ventilation (LPV) with a tidal volume (Vt) of 7 ml kg− 1 ideal body weight (IBW), 10 cmH2O positive end-expiratory pressure (PEEP) combined with regular recruitment maneuvers (RMs) or conventional ventilation (CV) with a Vt of 10 ml kg− 1 IBW, 0 cmH2O in PEEP and no RMs. The primary endpoints were the changes in the ratio of PaO2 to FiO2 (P/F). The secondary endpoints were the differences between the two groups in PaO2, alveolar-arterial oxygen gradient (A-aO2), intraoperative pulmonary mechanics and the incidence of atelectasis detected on chest x-ray on the first postoperative day. Results In comparison to CV group, the intraoperative P/F and PaO2 in LPV group were significantly higher while the intraoperative A-aO2 was clearly lower. Cdyn and Cstat at all the intraoperative time points in LPV group were significantly higher compared to CV group (p Conclusions Lung protective mechanical ventilation significantly improved intraoperative pulmonary oxygenation function and pulmonary compliance in patients experiencing various abdominal laparoscopic surgeries, but it could not ameliorate early postoperative atelectasis and oxygenation function on the first day after surgery. Trial registration https://www.clinicaltrials.gov/identifier: NCT04546932 (09/05/2020).

Keyphrases provide an overview of the articles, making it a powerful tool for categorizing scientific articles. This paper introduces and describes our supervised machine learning model for automatic keywords extraction. The model calculates features from traditional statistical metrics and new state-of-the-art sentence embeddings to predict a confidence score annotating conformity of keyphrase candidate. The model is tested on corpora of Russian as well as English scientific articles. When compared to the chosen baseline methods of the experiment, our model achieved a comparable F1 score when applied to the Russian corpora; and outperformed them when applied to the English corpora. Using F1-score as the evaluation metric, we also experimented with the model's parameters, such as the embedder and the set of features used as input. We found the pre-trained embedder that provides the best possible outcome for our task and confirmed that our model works best with the full set of features - non of the input to the model is redundant. For future works, we set our goal on deploying the model on existing system. Moreover, we suggest training a delicated embedding module to improve the model performance when working with articles written in Russian.

With the increasing amount of pornography being uploaded on the Internet today, arises the need to detect and block such pornographic websites, especially in Eastern cultural countries. Studying pornographic images and videos, show that explicit sensitive objects are typically one of the main charac-teristics portraying the unique aspect of pornography content. This paper proposed a classification method on pornographic visual content, which involved detecting sensitive objects using object detection algorithms. Initially, an object detection model is used to identify sensitive objects on visual content. The detection results are then used as high-level features combined with two other high-level features including skin body and human presence information. These high-level features finally are fed into a fusion Support Vector Machine (SVM) model, thus draw the eventual decision. Based on 800 videos from the NDPI-800 dataset and the 50.000 manually collected images, the evaluation results show that our proposed approach achieved 94.06% and 94.88% in Accuracy respectively, which can be compared with the cutting-edge pornographic classification methods. In addition, a pornographic alerting and blocking extension is developed for Google Chrome to prove the proposed architecture’s effectiveness and capability. Working with 200 websites, the extension achieved an outstanding result, which is 99.50% Accuracy in classification.

An Identity-Based Encryption (IBE) scheme uses public identities of entities for cryptographic purposes. Unlike that, we introduce a new scheme which is based on private identities, and we call it Private Identity-Based Encryption. A Private IBE scheme makes sure the adversaries cannot get the information that somebody uses for encryption in order to decrypt the data. Moreover, thanks to using identities as secret keys, an user-friendly system can be designed to support users in protecting data without storing any keys privately. This allows builds decentralized applications to manage keys that is often long and difficult to remember.

Network Function Virtualization (NFV) is a prominent technology that replaces the traditional hardware network node by the virtualized network software. Along with the development in the software field that divides an application into microservices, the container appears to adapt the reliability, availability, operationality of the application. To facilitate the development of the I/O intensive in the high-density container environment, the combination OVS and DPDK are perfect that increases performance significantly. In this paper, we design and integrate OVS-DPDK in container networking in two cases. We deployed the two containers in a host and used OVS-DPDK as a virtual bridge connecting them in the first case. In the second case, we configured the system on two hosts. Then we measured the throughput, CPU usage, and evaluated OVS and OVS-DPDK in both cases.

The unprecedented proliferation of recent large-scale and multi-omics databases of cancers has given us many new insights into genomic and epigenomic deregulation in cancer discovery in general. However, we wonder whether or not there exists a systematic connection between copy number aberrations (CNA) and methylation (MET)? If so, what is the role of this connection in breast cancer (BRCA) tumorigenesis and progression? At the same time, the PAM50 intrinsic subtypes of BRCA have gained the most attention from BRCA experts. However, this classification system manifests its weaknesses including low accuracy as well as a possible lack of association with biological phenotypes, and even further investigations on their clinical utility were still needed. In this study, we performed an integrative analysis of three-omics profiles, CNA, MET, and mRNA expression, in two BRCA patient cohorts (one for discovery and another for validation) - to elucidate those complicated relationships. To this purpose, we first established a set of CNAcor and METcor genes, which had CNA and MET levels significantly correlated (and anti-correlated) with their corresponding expression levels, respectively. Next, to revisit the current classification of BRCA, we performed single and integrated clustering analyses using our clustering method PINSPlus. We then discovered two biologically distinct subgroups that could be an improved and refined classification system for breast cancer patients, which can be validated by a third-party data. Further studies were then performed and realized each-subgroup-specific genes and different interactions between each of the two identified subgroups with the age factor. These findings can show promise as diagnostic and prognostic values in BRCA, and a potential alternative to the PAM50 intrinsic subtypes in the future.

This paper focuses on detecting and classifying pornographic content (images and videos) by using a multi-level CNN model with some supportive models. The main approaching method is to determine the images (keyframes extracted from videos) containing sensitives content or not by applying object detection model Mask R-CNN, which is the completely new approaching method in pornographic recognition. Moreover, the proposed model also adapts some other methods such as feature extraction and classifying based on CNN to increase the accuracy of the adaptive methods and ignore non-pornographic images and videos. Experimental results using the Pornography-800 and Pornography-2K datasets, performance of our method is reaching the accuracy of 92.13% and 90.40% respectively, show the effectiveness of the proposed method.

Eating behaviors and food consumption motivations have been important research topics in consumer, nutrition, and food literature. This study aims to examine the impact of some key factors (i.e., nationalism, materialism, cultural values, and promotion focus) on the consumption of traditional food and fast food in an emerging market. Using a sample data of 691 urban consumers in China, results of structural equation modeling reveal that nationalism appears to be an important predictor of traditional personal value, while materialism is a major factor that enhances modern personal value. Additionally, promotion focus has a positive mediating effect on the relationship between traditional personal value and traditional food purchase intention and that between modern personal value and fast food purchase intention. Notably, the total effect of modern personal value on fast food purchase intention is stronger than the total impact of traditional personal value on traditional food purchase intention. This study provides fresh insights into motivations for traditional food and fast food consumption in China and have important implications for food marketers and policymakers who aim at promoting favorable eating behaviors.

This paper presents an experimental study on the seismic performance of a novel composite joint between reinforced concrete columns and steel beams (RCSs) for frame structures. In the proposed RCS joint, an H steel profile totally embedded inside an RC column is directly welded to the steel beam. The H steel profile was covered by two supplementary plates to avoid the stirrups resisting the shear in the connection region. Two full-scale joints were built and tested under reversed-cyclic loading at the University of Transport and Communications of Vietnam. Seismic performance in terms of load-bearing capacity, story drift capacity, energy dissipation, and stiffness degradation were evaluated. The test specimen showed a good response to cyclic load reversals.

International audience; The interface bond between layers plays an important role in the behavior of pavement structure. However, this aspect has not yet been adequately considered in the pavement analysis process due to the lack of advanced characterizations of actual condition. In many pavement design procedures, only completely bonded or unbounded interfaces between the layers are considered. For the purpose of the better evaluation of the asphalt pavement behavior, this work focused on its investigation taking into account the actual interface bonding condition between the asphalt layers. Based on the layered theory developed by Burmister (1943), the actual interaction between pavement layers was taken into account by introducing a horizontal shear reaction modulus which represents the interface bonding condition for a given state. The analytical solution was then implemented in a numerical program before doing forward calculations for sensitivity analysis which highlights the influence of the interface bonding conditions on the structural behaviors of asphalt pavement under a static load. Furthermore, the numerical program was applied through an original experimental case study where falling weight deflectometer (FWD) tests were carried out on two full-scale pavement structures with or without a geogrid at the interface between the asphalt layers. Backcalculations of the FWD measurements allowed determining field condition of the interface bond between the asphalt layers. The obtained values of the interface shear modulus in pavement structure with a geogrid are smaller than the ones in pavement structure without geogrid. Moreover, all of these values representing field performance are at the same order of magnitude as those from dynamic interlayer shear testing.

In this paper, we proposed a new approach for pornographic classification by recognizing sensitive objects on images. To handle the misdetection and wrong judgment, a novel training strategy named additional learning was developed to help object detection model learns from mistakes, therefore increasing the method performance. Furthermore, a separate SVM classifier was trained to classify pornography and benign images from sexual object detected using Mask R-CNN model. Benchmarked by the NPDI-800 dataset, our proposed method achieved an accuracy of 84.625% and 90.125%, before and after applying additional learning strategy respectively. Besides, our proposed model also improves the false positive rate from 22.16% to 3.56% in our manually collected dataset.

This paper presents an experimental campaign and a design method for concrete-steel hybrid walls with several embedded steel profiles. In the first part of the paper, an extensive experimental investigation on the static behavior of hybrid walls subjected to combined shear and bending is presented. Six full-scale hybrid walls with different types of the structural steel-concrete connection and reinforcement detailing were tested. The experimental results indicated that the load bearing capacity of the hybrid specimens considerably grows, as a result of the encased steel profiles. It was found that specimens with shear connectors (i.e. headed studs, stiffeners) are more ductile in terms of displacement ductility than the ones without connectors. Next, a design model for hybrid elements (walls and columns) subjected to combined axial force, bending and shear is proposed. This model is based principally on the design rules of Eurocode 2 and Eurocode 4. Particular attention is paid to longitudinal and transversal shear resistances. A strut-and-tie model is developed to evaluate the transverse shear resistance taking into account the contribution of the steel profiles. Furthermore, an analytical method is proposed for the prediction of the longitudinal shear stress at the concrete-steel profile interface which allows to design adequate shear connection between the steel profile and concrete. Finally, to assess the validity of the developed design model a comparison between the experimental results and design predictions is presented.

This paper deals with an experimental study on seismic performance of a new type of exterior RCS connection, in which a steel profile embedded inside RC column is directly welded to the steel beam. A full scale exterior hybrid joint was built and tested under reversed-cyclic loading at the University of Transport and Communications of Vietnam. Seismic performance in term of load bearing capacity, story drift capacity, ductility, energy dissipation and stiffness degradation were evaluated. The test specimen showed a good response to cyclic load reversals. The experimental results indicated that the test specimen performed in a ductile manner and the stiffness degradation during the cycles performed was gradual. It was concluded that the studied RCS joint could be used as dissipative element in the structures of ductility class medium (DCM).

Bonding conditions between pavement layers have an important influence on the responses of pavement structure. This paper deals with numerical analysis for the stresses, strains and deflections of double-layered asphalt pavement structure. The constitutive relations are based on the layered homogeneous half-space theory developed by Burmister (1943). In this work, in order to improve the modelling, the actual interaction between the layers is taken into account by considering a horizontal shear reaction modulus which represents the interface bonding condition. The numerical model is validated and applied through an original case study where falling weight deflectometer (FWD) tests are carried out on two full-scale pavement sections with two different bonding conditions at the interface between asphalt layers. The results indicate that the considered numerical model allows evaluating and quantifying the interface bonding condition in determining by backcalculation the horizontal shear reaction modulus at the pavement interface.

An enhanced multi-fiber beam element suitable for the analysis of reinforced concrete members subjected to combined loadings is presented. The model is developed using displacement-based formulation with small displacement assumption. The section kinematics is based on the kinematic assumptions of a two-node Timoshenko beam and enhanced by introducing additional degrees of freedom at each section in order to take into account the warping phenomenon. A system of fixed points is created and interpolated by Lagrange functions and polynomials. In order to take into account the contribution of stirrups, a discretization of control sections into different regions following its material response is applied. As a result, the basic assumptions of the Modified Compression Field Theory with a secant-stiffness formulation is used to represent the constitutive material model for reinforced concrete. The model is validated by comparing to the theoretical formulations and several experimental tests. The simulations include a variety of monotonic load conditions under bending, shear and torsion for specimens with rectangular section.

Over the recent years, there has been increasing research activities made on improving the efficacy of Memetic Algorithm (MA) for solving complex optimization problems. Particularly, these efforts have revealed the success of MA on a wide range of real world problems. MAs not only converge to high quality solutions, but also search more efficiently than their conventional counterparts. Despite the success and surge in interests on MAs, only restricted theoretical knowledge is available in the field of MA and limited progress has been made on formal memetic frameworks. The key design issue of MA lies in the successful promotion of competition and cooperation between the forces of evolution and individual learning through appropriate configuration of the algorithmic parameters. This can be achieved by 1) applying different parameter configurations to find the most suitable setting or 2) adapting the algorithmic parameters of MAwhile the search progresses. While the former is straightforward, it could only produce reasonable configurations that are suitable for solving a given problem at hand. Further, such an option may not be feasible due to the high computational cost involved. The latter, on the other hand, may be applied to a wide range of problems more efficiently, but would require suitable online adaptation schemes and frameworks. This thesis provides some insights into the success of MAs and summarizes investigation on the study of effective memetic frameworks. It addresses several important design issues of MAs in the context of continuous optimization problems and proposes two adaptive approaches to efficiently and effectively configure the MA design parameters during the search process. Subsequently, a formal probabilistic memetic framework is presented to highlight the interrelationship among the MA design issues. Finally, the thesis presents a complexity analysis on the numerical methods as individual learning in MAs. i ATTENTION: The Singapore Copyright Act applies to the use of this document. Nanyang Technological University Library

We have successfully developed a prototype of a cost-effective, scalable and QoS provision capable SDN switch for IoT communication. The proposed system, that is based on Raspberry pi 3, uses Raspbian operating system and Open vSwitch software. It is compatible with OpenFlow 1.3 and includes four 100 Mbps Ethernet ports. Thanks to taking the advantages of SDN technology, open source software and low-cost mini-computer platform, the developed SDN switch system has a reasonable cost while it is flexible, scalable and still fully supports advanced network functions, i.e. QoS provisioning. The switching system also can be deployed as a network device with various functions such as hub, switch, router, firewall, … which is determined by a controlling program installed in the SDN controller. The switch configuration and its performance have been verified by testing experiments. We have, then, also run an experimental demonstration of QoS provisioning scenario with our developed SDN switch for IoT network. The obtained numerical results proved the flexibly QoS provisioning capability of the developed SDN switch. Our switch system can be a promising device for creating flexible and cost-effective IoT communication infrastructure.

[EN] Standard buildings in steel and in reinforced concrete are constructed by two different industrial sectors with little interaction. Even steel-concrete composite buildings remain designed as steel structures, with a limited benefit of the presence of concrete slabs. For some years however, a more integrated design between both materials is used, merely in high rise and heavy loaded structures. This new trend is not supported by actual standards that give little guidance for the specific arrangements that come from this new practice. The RFCS SMARTCOCO research project is intended to fill these gaps in knowledge and provide design guidance for some composite elements covered neither by Eurocode 2 nor by Eurocode 4 : composite columns or walls reinforced by several fully encased steel sections, reinforced concrete columns reinforced by one steel section over the height of one storey and concrete flat slabs or beams connected to columns or walls by means of steel shear keys. Gaps in knowledge are mostly related to force transmission between concrete and embedded steel profiles. A generic design approach has been developed and then used to design test specimens. The results have been used to calibrate the design proposals. The output is a design guide which complements Eurocode 2 and 4., This paper was developed in the frame of the SMARTCOCO project funded by RFCS, the Research Fund for Coal and Steel of the European Commission, Research grant agreement RFSR-CT-2012-00031 Smartcoco. The companies BESIX and ArcelorMittal are also acknowledged for their involvement in the project.

Hybrid RCS frames consisting of reinforced concrete (RC) column and steel (S) are used frequently in practice for mid- to high-rise buildings. RCS frames possess several advantages from structural, economical, and constructional view points compared to either traditional RC or steel frames. One of the key elements in RCS frames is the beam–column joints. This paper deals with numerical study on static response of a new reinforce concrete-steel (RCS) exterior beam–column joint. The studied beam–column joint detail is a through-column type in which an H steel profile totally embedded inside RC column is directly welded to the steel beam. The H steel profile was covered by two supplementary plates in the joint area. This detail provides two main advantages: The column is continuous, and no stirrups in the joint area are needed. The nonlinear behavior of the new joint is studied numerically and showed that this proposed joint is suitable as a special moment connection. In addition, the parametric studies are carried out to investigate the influences of the stirrups, the encased profile length, and supplementary plate length on the behavior of the joint.

Hybrid reinforced concrete steel (RCS) frames consisting of reinforced concrete (RC) column and steel (S) are used frequently in practice for mid-to-high-rise buildings. RCS frames possess several advantages from structural, economical and construction view point compare to either traditional RC or steel frames. One of the most important elements in RCS frames is the composite shear wall consisting of several steel sections encased in reinforced concrete. Regarding the RC walls reinforced by more than one steel profile, namely “Hybrid” wall, although number of researchers have focused on its various aspects, they are currently not covered by standards because they are neither reinforced concrete structures in the sense of Eurocode 2 (1992) or ACI-318 (2005) nor composite steel-concrete structures in the sense of Eurocode 4 (1994) or AISC-2010 (2010). An experimental study on the static behavior of hybrid walls with several embedded steel profiles subjected to combined shear and bending is presented. Six hybrid walls with different types of the structural steel-concrete connection and reinforcement detailing are tested. The specimens exhibited ductility behavior. The experimental results indicate that the load bearing capacity of the hybrid specimens considerably grows, as result of the encased steel profiles. The specimens with shear connectors (i.e. headed studs, stiffeners) were more ductile in terms of displacement ductility than the ones without connectors.

International audience; This paper presents a numerical study on concrete confinement and degree of shear connection effects on the ultimate load of hybrid steel-concrete columns with several encased steel profiles. Primarily, a co-rotational finite element for large displacement analyses of hybrid beam-columns in partial interaction and with shear deformability of concrete component is developed. In local co-rotational coordinate system, a fiber model considering the triaxial stress state in the concrete component is adopted. This consideration enables to take into account the contribution of the transverse reinforcement on concrete confinement by using the extended plane stress algorithm, in which the transversal equilibrium between the concrete fiber and the transverse reinforcing bar is imposed. The performance of the FE model is illustrated by comparing its results against experimental three-point flexural bending tests of hybrid beams. The results of parametric study using the FE model show that for low to high column slenderness, the ultimate load of hybrid column increases significantly with respect to the transverse reinforcement ratio. Besides, the ultimate load of slender columns in full interaction can be obtained for columns with a relatively high shear connection stiffness at the extremities without shear connection along the column height. © Springer International Publishing AG 2018.

International audience; This paper deals with the development of a non-linear finite element model for reinforced concrete members under torsion. Using multi-fiber approach and displacement-based formulation, an enhanced multi-fiber 3D beam is proposed for predicting the behavior of reinforced concrete elements under torsion. The sectional analysis under elastic torsion is considered following Saint-Venant torsional theory for beam in order to take into account the effect of warping phenomenon. Elastic behavior under large displacements is also investigated in this model using a second-order approximation of the Green-Lagrange strains. In the inelastic domain, after cracking, following the space truss theory, the whole element is assumed to act as a tube, meaning the applied torsional moment is resisted only by the shear flow in the wall of the tube. Then, the effective wall thickness of the member after cracking is determined by an empirical formulation developed by the authors. Moreover, the section is discretized into different regions following its material response. In each region, depending on its characteristics, an appropriate constitutive material model is applied. For the concrete, the proposed behavior models are based on the Modified of Compression Field Theory and its extension. In order to correctly predict the torsional response, the authors proposed some modifications in the tensile behavior of concrete, based on experimental tests in torsion. In the elastic domain, the model is validated by comparing to the analytical solution and some results from other researches. In the inelastic field, a good agreement is obtained between a series of experimental tests and numerical results.

International audience; The case of a push-out test specimen made of prefabricated slabs connected by means of grouped headed studs is investigated in this study. In order to analyse the behaviour of such a shear connection, an experimental study and a numerical analysis have been developed. This paper deals with the presentation of numerical results linked to the parametric study of several layout and loading conditions. The specific 2D nonlinear finite element model developed by two first authors has been presented in a previous paper. This specific finite element model has been developed in order to avoid convergence problems that sometimes occur with the introduction of contact-friction elements in 3D models. In addition, this simplified 2D model allows reducing considerably the time computation when the model concerns the study of a structure at real scale. This 2D nonlinear model is supposed to approach the 3D problem using a ''zone-equivalence'' methodology which we briefly recall the theoretical background. Material nonlinear constitutive laws, 4-noded plane elements and frictional contact finite elements were introduced in the model at the steel concrete interface between the girder flange and the concrete slab and between the studs and the filling concrete. Numerical simulations concerned by this work lead to highlight the internal force transfer mechanisms through the specimen for several layouts and loading conditions, such as the stud arrangements, the filling concrete performance, the reinforcement percentage of the slab, the restrain slab conditions and especially the combination of axial and shear loads. These results could be helpful to have a better interpretation of the push-out test measurements in accordance with the specimen arrangement and the test procedure.

International audience; The authors present the exact finite element formulation for partially connected shear-deformable elastic hybrid beam-columns with several embedded sections. Euler-Bernoulli's kinematic assumptions are adopted for the embedded section whereas Timoshenko's kinematic assumptions are considered for the encasing element. The shear connection between the encasing component and the embedded section is modeled through a continuous relationship between the interface shear flow and the corresponding slip. A set of coupled system of differential equations in which the primary variables are the slips and the shear deformation of the encasing cross-section is derived from the governing equations describing the behavior of an elastic shear-deformable hybrid beam-column in partial interaction. This coupled system has been solved in closed-form, and the ''exact " stiffness matrix has been derived using the direct stiffness method. The latter has been implemented into a general displacement-based finite element code, and has been used to investigate the behavior of shear-deformable hybrid beams. Three numerical examples have been considered in order to assess the capability of the proposed formulation and to investigate the effect of the shear connection stiffness and span-to-depth ratios on mechanical responses of the beam-columns. It has been found that the transverse displacements are more affected by the shear flexibility than the slips.

Computational offloading has been shown being a promising approach to prolong the battery life of smartphones. To come up with energy-efficient offloading strategies, it is crucial to understand how much energy is used not only for local computation but also for network communication. Therefore, reliable methods to measure the energy consumption of the phones are needed as a fundamental basis. In this paper, we evaluate the accuracy of the Android smart battery interface. As a second contribution, we also designed a new, portable and cheap microcontroller-based power monitoring device. We conduct energy measurement experiments for a set of typical applications including local computations as well as WiFi and 3G operations. Our results show that both our device and smart battery interface can be used to estimate the energy consumed by the applications running on the phone. The smart battery interface, however, clearly underestimates in idle status. We see our measurements as an important step towards the development of more accurate offloading strategies for smartphones.

Computational offloading from smartphones into the cloud has proved to be one of useful approaches for improving energy efficiency. To assess the benefit of offloading and decide the most suitable offloading strategies, it is essential to account the energy consumption of smartphones. In this paper, we investigate the accuracy and capabilities of the Android smart battery interface. For comparison, we measure the energy consumption using an oscilloscope. We experimentally investigate the energy consumption of different applications on a modern smartphones including local computation and network communication over WiFi. Our results show that both of methods bring high accuracy. Our work builds the basis for next generation offloading algorithms.

This paper presents the exact finite element formulation for the analysis of partially connected shear-deformable multi-layered beams. Timoshenko's kinematic assumptions are considered for each layer or component, and the shear connection is modeled through a continuous relationship between the interface shear flow and the corresponding slip. The effect of possible transversal separation of the two adjacent layers has not been considered. The governing equations describing the behavior of a shear-deformable multi-layered beam in partial interaction consist of a set of coupled system of differential equations in which the primary variables are the slips and the shear deformations. This coupled system has been solved in closed form, and the "exact" stiffness matrix has been derived using the direct stiffness method. The latter has been implemented in a general displacement-based finite element code, and has been used to investigate the behavior of shear-deformable multi-layered beams. Both a simply supported and two continuous beams have been considered in order to assess the capability of the proposed formulation and to investigate the influence of the shear connection stiffness and span-to-depth ratios on mechanical responses of the beams. It has been found that the transverse displacement is more affected by shear flexibility than the interlayer slips. HighlightsShear-deformable multi-layered beams in partial interaction.Solution strategy of the coupled governing differential equations.Derivation of the exact finite element model.Shear-deformable model versus the shear-rigid model.Influence of shear-connection stiffness and the span-to-depth ratio on the overall structural response.

International audience; This paper presents a mixed finite element (FE) model for the nonlinear time-dependent analysis of composite beams with partial shear connection. The key idea is to consider, as a first approach, a viscoelastic/plastic model for the concrete slab in order to simulate the interaction between the time effects of concrete, such as creep and shrinkage, and the concrete cracking. Creep is taken into account via linear aging viscoelasticity, while cracking is modeled using an elastoplastic model with softening. A nonlinear isotropic/kinematic hardening model is adopted for steel behavior and an appropriate nonlinear constitutive relationship is utilized for the shear stud. A consistent time integration is performed by adopting the Euler backward scheme. Finally, comparisons between the numerical results and experimental data available in the literature are undertaken to validate the accuracy of the model. It is shown that the interaction between cracking and time effects (creep and shrinkage) significantly increases the deflection.

SUMMARY The aim of this paper is to investigate the plastic rotation capacity of composite beams as well as the overstrength factors for composite joints considering the actual European steel production. It relies on the statistical data of the mechanical properties of steel profiles and reinforcement bars produced in several European steel mills that have been collected during the European research project OPUS. Several steel and composite structures have been designed following the EN 1998 rules, and the effect of the statistical distribution of the steel properties on the design has been analyzed. In such structures, the first attainment of the rotation capacity is expected to happen in the hogging region. The plastic rotation capacity was evaluated using the so-called standard beam concept. The moment–rotation curve was constructed by joining together the pre-buckling branch, determined using a fiber model, and the post-buckling part derived by considering the local plastic failure mechanism as suggested by Gioncu. A program in MATLAB (MATLAB version 7.10.0. Natick, Massachusetts: The MathWorks Inc., 2010) was developed to establish such curve for arbitrary composite beams. The predictions of the model compare favorably against the experimental results. On the basis of the probabilistic model for the mechanical properties of steel, we derive the statistical distribution of the maximum rotation defined at the intersection of the pre-buckling and post-buckling curves. Next, we estimate the so-called overstrength factors. Copyright © 2012 John Wiley & Sons, Ltd.

The present paper is concerned with the elastic design optimisation of continuous composite beams. This optimisation is based on the analysis of the beam in the inelastic range including the concrete creep and shrinkage, the tension stiffening and temperature difference effects as well as the possible local buckling instability. The finite ele-ment program PONTMIXTE (adapted to study continuous beams at real scale with short time computation) is first presented with its different sections: Pre-design (in accordance with Eurocode specifications), Non linear finite element calculation and Post-processing. In order to validate the proposed model, the numerical calculations are compared against experimental results from tests on a two-span beam in reduced scale (7.5 m length for each span) without taking into account the local buckling phenomenon avoided in the experimental test by using web-stiffeners. Next, special attention is paid to study the influence of the local buckling instability on the internal moment redistribution coefficient between hogging and sagging zones. The application concerns different 3-span beams of bridge at real scale with medium span lengths (40–60–40 m). The post-buckling behaviour represented by moment-rotation curves (M-θ) is deduced from a 3D finite element model of the cross-section developed using Castem finite element code. The M-θ curves describing the local buckling phenomenon are approximated using hyperbolic functions and implemented in PONTMIXTE using a specific rotational spring finite element. The influence of this instability on the moment redistri-bution coefficients calls the Standart predictions into question.

International audience; This paper presents a space-exact, time-discretized solution for the time-dependent analysis of composite beams with partial interaction. The time effects considered in this model are creep and shrinkage of the concrete slab. The constitutive model adopted to describe the time effects is linear viscoelasticity with time-dependent coefficients to account for ageing. By using the time-discretized form of the constitutive relations, the equilibrium equations in terms of the displacements at a generic instant are analytically solved. Based on the analytical expressions (exact in space) of the displacements and the internal forces, the space-exact stiffness matrix is deduced for a generic composite beam element. This stiffness matrix can be used in a displacement-based procedure for the time-analysis of continuous composite steel-concrete beams with arbitrary support and loading conditions. The present formulation requires a minimum number of elements depending on the support and loading conditions. The proposed hybrid analytical-numerical method is used to investigate both the short-term and the long-term deflections of simply supported composite beams in order to assess the calculation method proposed in Eurocode EN 1994-1-1 [21]. The effects of creep, shrinkage and degree of shear connection on the deflection of simply supported composite beams are also analyzed. The long-term deflection calculated with the analytical model based on the rules given in EN 1994-1-1 [21] is compared against the one predicted by the proposed model. It is found that EN 1994-1-1 [21] slightly underestimate the long-term deflection. It was also observed that the contribution of shrinkage to the deflection is more significant than suggested in EN 1994-1-1 [21].

The discovery of low-energy stable and meta-stable molecular structures remains an important and unsolved problem in search and optimization. In this paper, we contribute two stochastic algorithms, the archiving molecular memetic algorithm (AMMA) and the archiving basin hopping algorithm (ABHA) for sampling low-energy isomers on the landscapes of pure water clusters (H2O)n. We applied our methods to two sophisticated empirical water cluster models, TTM2.1-F and OSS2, and generated archives of low-energy water isomers (H2O)n n=3-15. Our algorithms not only reproduced previously-found best minima, but also discovered new global minima candidates for sizes 9-15 on OSS2. Further numerical results show that AMMA and ABHA outperformed a baseline stochastic multistart local search algorithm in terms of convergence and isomer archival. Noting a performance differential between TTM2.1-F and OSS2, we analyzed both model landscapes to reveal that the global and local correlation properties of the empirical models differ significantly. In particular, the OSS2 landscape was less correlated and hence, more difficult to explore and optimize. Guided by our landscape analyses, we proposed and demonstrated the effectiveness of a hybrid local search algorithm, which significantly improved the sampling performance of AMMA on the larger OSS2 landscapes. Although applied to pure water clusters in this paper, AMMA and ABHA can be easily modified for subsequent studies in computational chemistry and biology. Moreover, the landscape analyses conducted in this paper can be replicated for other molecular systems to uncover landscape properties and provide insights to both physical chemists and evolutionary algorithmists.

This article presents a new non-linear finite element formulation for the analysis of two-layer composite plane beams with interlayer slips. The element is based on the corotational method. The main interest of this approach is that different linear elements can be automatically transformed to non-linear ones. To avoid curvature locking that may occur for low order element(s), a local linear formulation based on the exact stiffness matrix is used. Five numerical applications are presented in order to assess the performance of the formulation.

Memetic algorithms (MAs) represent one of the recent growing areas in evolutionary algorithm (EA) research. The term MAs is now widely used as a synergy of evolutionary or any population-based approach with separate individual learning or local improvement procedures for problem search. Quite often, MAs are also referred to in the literature as Baldwinian EAs, Lamarckian EAs, cultural algorithms, or genetic local searches. In the last decade, MAs have been demonstrated to converge to high-quality solutions more efficiently than their conventional counterparts on a wide range of real-world problems. Despite the success and surge in interests on MAs, many of the successful MAs reported have been crafted to suit problems in very specific domains. Given the restricted theoretical knowledge available in the field of MAs and the limited progress made on formal MA frameworks, we present a novel probabilistic memetic framework that models MAs as a process involving the decision of embracing the separate actions of evolution or individual learning and analyzing the probability of each process in locating the global optimum. Further, the framework balances evolution and individual learning by governing the learning intensity of each individual according to the theoretical upper bound derived while the search progresses. Theoretical and empirical studies on representative benchmark problems commonly used in the literature are presented to demonstrate the characteristics and efficacies of the probabilistic memetic framework. Further, comparisons to recent state-of-the-art evolutionary algorithms, memetic algorithms, and hybrid evolutionary-local search demonstrate that the proposed framework yields robust and improved search performance. Published version

This paper describes an experiment using an automated tool for testing smart cards embedded software developed in C. Conventional testing of smart cards uses low-level commands and writing the use cases and test scripts is an error-prone and tedious task. Our goal was to show how one can use a formal tool to improve the testing process in order to concentrate better on the efficiency of the test. The approach consists in modeling each layer of the system independently while abstracting the services provided by the lower layers. The model is then verified, simulated and test cases are automatically generated using test criteria such as reachable state coverage and transition coverage. We also developed a translator to execute those test cases on the C implementation of the system. We show the results obtained and the lessons learned from the application of this approach to the validation phase of a smart cards file system manager.

International audience; Cracking of the concrete slab in the hogging moment region decreases the global stiffness of composite steel-concrete structures and also reduces the effect of continuity, thus making the structural behaviour highly nonlinear even for low stress levels. In this paper, the behaviour of continuous composite beams with discrete shear connection is investigated using a nonlinear mixed finite element model. The model includes appropriate nonlinear constitutive relationships for the concrete, the steel and tension stiffening effect. Furthermore, the discrete nature of the shear connection is embedded in the model and the tension stiffening effects are introduced in the analysis by using a concrete constitutive model proposed in the CEB-FIB Model Code 1990 which incorporates embedded steel. Special attention is paid to the hogging moment regions, where cracking occurs. Comparisons between the numerical analyses and experimental results in the current literature are undertaken to validate the accuracy of the model. Furthermore, a parametric study is carried out to study the influence of span length and degree of shear connection on the strength and ductility of continuous composite beams.

International audience; This paper deals with numerical investigations on second-order effects in slender RC columns reinforced by several steel sections, namely hybrid columns, subjected to combined axial load and uniaxial bending moment. A FE model is developed in which geometrical and material nonlinearities as well as the partial interaction effect between the steel profiles and the surrounding concrete are taken into account. This model is then used to perform an extensive numerical parametric study on the ultimate load of hybrid columns considering 1140 different data sets. The comparison between the results obtained with FE analysis and Eurocode simplified methods (moment magnification approach) shows that EC2 and EC4 methods give wide discrepancies where half of case-studies are unsafe. The aim of the paper is to extend the use of the Eurocode moment magnification method to slender hybrid column design. In this method, the second-order bending moment is calculated by multiplying the first-order one by a magnification factor k that depends on the flexural stiffness EI and the equivalent moment distribution. New expressions for the correction factors involved in the determination of the effective flexural stiffness EI are proposed and calibrated by the results of the extended parametric study with 2960 data sets. The comparison of the predictions given by the new expressions against the FE analysis shows that the proposed new expressions of correction factors for moment magnification method provides largely safe designs for slender hybrid columns.

International audience; This article presents a new co-rotational finite element for the large displacement analysis of hybrid steel–concrete beam/column with several encased steel profiles. The advantage of using the co-rotational approach is that the geometrical linear finite element formulation can be reused and automatically be transformed into geometrical nonlinear formulation. The exact stiffness matrix derived from the analytical solution of the governing equations for hybrid beam with longitudinal partial interaction is used for the local formulation. As a result, internal nodes used to avoid curvature locking encountered in low order polynomial finite elements are not required. Finally, five numerical applications are presented in order to illustrate the performance of the proposed formulation.

The present paper investigates the mechanical behavior of a novel dowel-type Timber-Concrete Composite system, namely SBB, under monotonic and reversed-cyclic loadings. This system consists of timber beams connected to a concrete slab using a dowel type connection. Because the structural behavior of timber-concrete composite slabs is mainly governed by the shear connection between concrete and timber, an extensive experimental program was carried out in order to assess its behavior under both monotonic (serviceability design) and cyclic loadings (seismic design) and to identify failure modes for each possible configuration. In order to fully characterize the load-slip behavior of the SBB connection under both monotonic and reversed cyclic loading, 24 Push-Out tests (12 under monotonic loading, 12 under reversed cyclic loading) were performed. The experimental program and the results (parameters and phenomenology) are discussed in this paper.

International audience; This paper presents a novel finite element model for the fully material and geometrical nonlinear analysis of shear-deformable two-layer composite planar beam/column members with interlayer slips. We adopt the co-rotational approach where the motion of the element is decomposed into two parts: a rigid body motion which defines a local co-ordinate system and a small deformational motion of the element relative to this local co-ordinate system. The main advantage of this approach is that the transformation matrices relating local and global quantities are independent from the choice of the geometrical linear local element. The effect of transverse shear deformation of the layers is taken into account by assuming that each layer behaves as a Timoshenko beam element. The layers are assumed to be continuously connected and partial interaction is considered by adopting a continuous relationship between the interface shear flow and the corresponding slip. In order to avoid curvature and the shear locking phenomena, the local linear element is derived from the force-based formulation. The present model provides an efficient tool for the elastoplastic buckling analysis of two-layer shear deformable beam/column with arbitrary support and loading conditions. Finally, two numerical applications are presented in order to assess the performance of the proposed formulation.

Over-the-air (OTA) application installation and updates have become a common experience for many end-users of mobile phones. In contrast, OTA updates for applications on the secure elements (such as smart cards) are still hindered by the challenging hardware and certification requirements. The paper describes a security framework for Java Card-based secure element applications. Each application can declare a set of services it provides and a set of services it wishes to call, and its own security policy. An on-card checker verifies compliance and enforces the policy; thus an off-card validation of the application is no longer required. The framework has been optimized in order to be integrated with the run-time environment embedded into a concrete card. This integration has been tried and tested by a smart card manufacturer. In this paper we present the formal security model of the approach, its overall architecture and the implementation footprint which can fit on a real secure element. We also report the lessons learned and the intricacies of integrating a research prototype with a protected loader of the manufacturer.

International audience; This paper deals with the buckling behavior of two-layer shear-deformable beams with partial interaction. The Timoshenko kinematic hypotheses are considered for both layers and the shear connection (no uplift is permitted) is represented by a continuous relationship between the interface shear flow and the corresponding slip. A set of differential equations is obtained from a general 3D bifurcation analysis, using the above assumptions. Original closed-form analytical solutions of the buckling load and mode of the composite beam under axial compression are derived for various boundary conditions. The new expressions of the critical loads are shown to be consistent with the ones corresponding to the Euler-Bernoulli beam theory, when transverse shear stiffnesses go to infinity. The proposed analytical formulae are validated using 2D finite element computations. Parametric analyses are performed, especially including the limiting cases of perfect bond and no bond. The effect of shear flexibility is particularly emphasized.

Steel–concrete composite beams are widely utilized as cost-effective structural solution in both buildings and bridges. Partial interaction through the possible occurrence of slips at the interface between the two connected members, strongly affects the behaviour of composite members and, therefore must be incorporated in theoretical models dealing with composite members. In addition, shear deformability of the two connected layers cannot be ignored in stocky members. Several computational models simulating the behaviour of composite beams including partial interaction and shear deformability with various degree of sophistication are currently available in the scientific literature. The present paper focuses on the background and the mechanical assumptions adopted in these models as well as structural characteristics which actually govern their predictions. Based on the kinematic assumptions involved, a threefold classification is proposed. The paper further clarifies the hierarchy between the three groups of models. To do so, the governing equations for each group of models are transformed into a proper dimensionless form by using mechanically sound dimensionless expressions of all functions of interest involved in the description of the mechanical response of the composite beam. A thorough parametrical study is presented which quantifies the influence of the identified dimensionless parameters. Furthermore, the study clearly indicates possible threshold values beyond which certain effects become negligible.