bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hybrid Copper‐Nanowire–Reduced‐Graphene‐Oxide Coatings: A “Green Solution” Toward Highly Transparent, Highly Conductive, and Flexible Electrodes for (Opto)Electronics
Authors: Aliprandi Alessandro , Moreira Tiago , Anichini Cosimo , Stoeckel Marc‐Antoine , Eredia Matilde , Sassi Ugo , Bruna Matteo , Pinheiro Carlos , Laia César A. T. , Bonacchi Sara , Samorì Paolo 
Published: September 2017

AbstractThis study reports a novel green chemistry approach to assemble copper‐nanowires/reduced‐graphene‐oxide hybrid coatings onto inorganic and organic supports. Such films are robust and combine sheet resistances (<30 Ω sq−1) and transparencies in the visible region (transmittance > 70%) that are rivalling those of indium–tin oxide. These electrodes are suitable for flexible electronic applications as they show a sheet resistance change of <4% after 10 000 bending cycles at a bending radius of 1.0 cm, when supported on polyethylene terephthalate foils. Significantly, the wet‐chemistry method involves the preparation of dispersions in environmentally friendly solvents and avoids the use of harmful reagents. Such inks are processed at room temperature on a wide variety of surfaces by spray coating. As a proof‐of‐concept, this study demonstrates the successful use of such coatings as electrodes in high‐performance electrochromic devices. The robustness of the electrodes is demonstrated by performing several tens of thousands of cycles of device operation. These unique conducting coatings hold potential for being exploited as transparent electrodes in numerous optoelectronic applications such as solar cells, light‐emitting diodes, and displays.
Tandem Cross Coupling Reaction of Alcohols for Sustainable Synthesis of β‐Alkylated Secondary Alcohols and Flavan Derivatives
Authors: Shee Sujan , Paul Bhaskar , Panja Dibyajyoti , Roy Bivas Chandra , Chakrabarti Kaushik , Ganguli Kasturi , Das Ayan , Das Gourab Kanti , Kundu Sabuj 
Published: September 2017

AbstractA Ru(II) NHC complex (loading down to 0.001 mol%) catalyzed cross coupling of a broad range of aromatic, aliphatic and heterocyclic alcohols is reported. This protocol also functioned efficiently under solvent‐free conditions. Remarkably, this catalytic system disclosed so far the highest TON of 288000 for the cross coupling of alcohols. Notably, this methodology was successfully applied for the one‐pot synthesis of a range of flavan derivatives. A detailed DFT studies and kinetic experiments were performed to understand the reaction mechanism as well as the high reactivity of this catalytic system.magnified image
New Condition for FD, All Filters, and New KYP Lemma
Authors: Stefanovski Jovan 
Published: September 2017

AbstractThis paper presents a necessary and sufficient condition for the
fault detection (FD) problem, under a quite general and natural assumption. The condition is actually a constant inertia on the extended imaginary axis (EIA) of a para‐hermitian rational matrix (RM). An observer solution is given. Another two main results are the presentation of all problem solutions, and a necessary and sufficient condition for constant inertia on the EIA or in a given frequency region, for a class of para‐hermitian RMs, in terms of linear matrix inequalities. The latter result can be regarded as a generalization of the Kalman‐Yakubovich‐Popov (KYP) lemma.
Velocity Reversal Systems: A Simple Friction Model for Telescopes
Authors: Kumar T. S. , Banavar Ravi N. 
Published: September 2017

AbstractIn this paper we experimentally characterize friction in an astronomical telescope and introduce a new model for capturing the observed behavior of friction in both the micro and macro displacement regimes of motion. The model is a modification of the LuGre model and is developed for velocity reversal systems like an astronomical telescope. The proposed model is represented with a pair of masses separated by a linear spring. This model is then employed to synthesize a feedback linearizable controller for the system. The simulation results for the proposed friction model in open loop are presented and validated with the experimental results. The stability aspects of the closed loop system with the modified friction model is then investigated. For estimating the unmeasurable states of the system used in feedback linearization, we discuss the observability of the system with the new model for friction.
Distributed Control Design for Spatially Interconnected Markovian Jump Systems With Time‐Varying Delays
Authors: Feng Hongyan , Xu Huiling , Xu Shengyuan , Chen Weimin 
Published: September 2017

AbstractThis paper focuses on spatially interconnected Markovian jump systems with time‐varying delays. Firstly, a sufficient condition is given to check the well‐posedness, stochastic stability and contractiveness of spatially interconnected systems with the effect of time‐varying delays and Markovian jumping parameters. Secondly, the distributed controllers which inherit the structure of the plants are designed. A sufficient and necessary condition is proposed to guarantee the existence of the distributed controllers. Finally, an illustrative numerical example is given to show the effectiveness of the results.
Synthesis and Multiple Incorporations of 2′‐O‐Methyl‐5‐hydroxymethylcytidine, 5‐Hydroxymethylcytidine and 5‐Formylcytidine Monomers into RNA Oligonucleotides
Authors: Tanpure Arun A. , Balasubramanian Shankar 
Published: September 2017

AbstractThe synthesis of 2′‐O‐methyl‐5‐hydroxymethylcytidine (hm5Cm), 5‐hydroxymethylcytidine (hm5C) and 5‐formylcytidine (f5C) phosphoramidite monomers has been developed. Optimisation of mild post‐synthetic deprotection conditions enabled the synthesis of RNA containing all four naturally occurring cytosine modifications (hm5Cm, hm5C, f5C plus 5‐methylcytosine). Given the considerable interest in RNA modifications and epitranscriptomics, the availability of synthetic monomers and RNAs containing these modifications will be valuable for elucidating their biological function(s).
Rotor‐Stator Spinning Disc Reactor: Characterization of the Single‐Phase Stator‐Side Heat Transfer
Authors: Kleiner Julia , Haseidl Franz , Hinrichsen Olaf 
Published: September 2017

AbstractThe single‐phase fluid‐stator heat transfer in a rotor‐stator spinning disc reactor in dependence on rotational Reynolds number, dimensionless throughput, Prandtl number, and aspect ratio is examined. For the selected ranges of these parameters, an increase in the stator‐side Nusselt number with increasing Reynolds number, Prandtl number, and a higher throughput is found. Laminar and turbulent flow regions are observed, which coincide with a throughput‐ and a rotation‐governed heat transfer regime, respectively. A Nusselt correlation to predict the experimental data in the turbulent flow regime within 20 % accuracy was established. A distinct increase in the overall volumetric heat transfer coefficient for a rise in Reynolds number was observed, being considerably higher compared to conventional tube reactors and twice as large in contrast with a similar rotor‐stator setup.
04.15: New design rules for tubes in combined walls in EN1993‐5
Authors: Gresnigt Nol , van Es Sjors , Karamanos Spyros , Vasilikis Daniel 
Published: September 2017

ABSTRACTSteel tubes can be applied for many applications, structural as well as in pipelines. They may be loaded by combinations of internal or external pressure, soil load, bending moment and normal force. Important failure modes are local buckling, severe ovalisation (flattening of the cross section) and rupture of the pipe wall at local buckles or welds.Within the framework of a European research project called Combitube sponsored by RFCS (Research Fund for Coals and Steel), the structural behaviour of spiral‐welded tubes for application in combined walls has been investigated. The main loads are bending moment, normal force, soil loads and loads from the infill sheeting.Analytical models were developed to predict the elastic‐plastic behaviour under these loads, i.e. the bending moment curvature diagram, the curvature ovalisation diagram and curvature strain diagrams.The analytical models as presented in this paper are an extension of previous analytical models developed for pipelines, now including more parameters that influence the load deformation behaviour, in particular local buckling. The new rules are intended for the new version of EN1993‐5 on Piling. They are validated with the results of full scale tests and extensive parameter studies.
05.32: Experimental and numerical study on the collapse behavior of an all‐steel accordion force limiting device
Authors: Poursharifi Maryam , Abedi Karim , Chenaghloua Mohammadreza 
Published: September 2017

ABSTRACTSpace structures are widely used to cover areas with no or few intermediate columns. These structures possess important features such as light weight, elegant appearance, fast production as well as ease of erection. Beside all these advantageous, space structures are prone to the progressive collapse, which more often occurs due to failure of compression members. Force limiting devices are used to alter space structure compression members' brittle post‐buckling behaviour to elastic‐perfectly plastic post buckling behaviour. In this study, an innovative type of all‐steel force limiting device is introduced. This force limiting device is designed based on buckling restrained braces and accordion metallic damper and called Accordion Force Limiting Device (AFLD). This force limiting device is consisted of accordion core, encasing and ball joints. Accordion core maximizes load bearing capacity while encasing prevents device from buckling. This device can assembled and disassembled very fast, so damaged members can substitute easily. One all‐steel Accordion Force Limiting Device (AFLD) were designed, constructed and tested under axial compressive loading. Results indicate that AFLD modifies brittle buckling behaviour of compression members. Also, a parametric study is carried out to improve AFLD behaviour. Numerical models are developed to investigate the effects of core material and the gap size between core and encasing.
06.01: Critical bridges in high‐speed railway lines: Systematic identification for specific trains
Authors: Unterweger Harald , Schörghofer DI Andreas , Taras Andreas 
Published: September 2017

ABSTRACTFor the design of railway bridges in railway lines with a speed limit above 200 km/h the dynamic effects have to be considered. The present design codes such as Eurocode (EN 1991‐2) achieve this by assuming different high‐speed load models (for example HSLM‐A) for the dynamic calculations of all railway bridges in the network. If train manufacturers design a new high‐speed train which fulfills the limits of the load model HSLM‐A (geometric and weight parameters), then no additional verification of the dynamic effects are required as all the railway bridges already comply with the HSLM‐A. New challenges arise if a train manufacturer decides to differ from these limits, as they may be uneconomic (for example short length of single car). Furthermore, a railway operator may wish to expand the use of high‐speed trains on traditional lines, which were, up to now, not verified for dynamic loads. In both cases, each single railway bridge in the railway network has to be recalculated by considering the geometry and weight parameters of the new developed train, which seems to be a cumbersome task. Therefore this paper deals at first with the different train parameters and their limits, which need to be fulfilled in order to be in line with the load model HSLM‐A and shows which of them are more critical than the others. This is done by assuming 8 different fictitious trains which fulfill or slightly exceed these limits. The different structural hazard is determined by performing systematic dynamic analyses for a large parameter range of single‐span bridges and train speeds. The second part of this paper deals with a methodology, which makes it possible to determine the critical bridges in high‐speed railway lines (critical length and critical first natural frequency) for a given train load model in order to reduce the total number of bridges to be investigated. In addition, the train signature curve is analysed with respect to support the dynamic analysis.
07.38: A GBT‐framework towards modal modelling of steel structures
Authors: Hansen Anders Bau , Jönsson Jeppe 
Published: September 2017

ABSTRACTIn modern structural steel frame design, the modelling of joints between beams and columns are based on very simple assumptions. The joints are most often assumed to behave as a perfect hinge or as a rigid joint. This means that in the overall static analysis relative rotations and changes in the moment curves due to joint deformations are neglected. This simplification eases the modelling but it is at the cost of losing a detailed understanding of the behaviour of the joint. This happens even though the European code has introduced the so‐called component method in order to determine the rotational stiffness of a connection. Based on a modelling of any beam‐to‐column joint using finite shell elements and springs for single components such as bolts, it is the primary hypothesis that it is possible to formulate a generalized connection model with few degrees of freedom related to a relevant set of deformation modes. This hypothesis is based on the idea of modal decomposition performed in generalized beam theories (GBT). The question is – is it possible to formulate an eigenvalue problem with a solution corresponding to mode shapes for the deformation of the joint by using the finite element model and some type of GBT beam elements? It is believed that this is possible. The paper will address our investigations and show the progress of our research.
10.37: Mechanical properties of high strength aluminium alloy at elevated temperatures
Authors: Su Mei‐Ni , Young Ben 
Published: September 2017

ABSTRACTThe mechanical properties of extruded aluminium alloys behave differently as temperature rises. Accurate prediction of the mechanical properties of aluminium alloys at elevated temperatures is necessary for determining the load‐carrying capacity of structures under fire conditions. This study focuses on the effects of high strength aluminium alloy 6061‐T6 at elevated temperatures. The melting point of aluminium alloy 6061‐T6 is found to be approximately 650°C. Therefore, tensile coupon tests were conducted at different temperatures ranging from approximately 24 to 600 °C for both steady and transient state tests. The material properties of aluminium alloy 6061‐T6 with plate thickness of 4.5 mm were obtained. The tests were performed using servo‐controlled hydraulic testing machine equipped with MTS 653 furnace. The Young's modulus, the yield strength (i.e. the 0.2% proof stress) and the ultimate strength versus different temperatures are also plotted and compared with the predictions from the American Aluminum Design Manual and Eurocode EN1999‐1‐2. The comparisons of the results are plotted and summarized in this paper, together with a detailed discussion. It is found that both the American Aluminum Design Manual and Eurocode generally provide conservative predictions for the high strength aluminium alloys at elevated temperatures.
12.19: Experimental investigation on residual stresses in welded thick‐walled I‐shaped sections fabricated from Q460GJ structural steel plates
Authors: Zhu Qian , Nie Shidong , Yang Bo , Xiong Gang , Dai Guoxin 
Published: September 2017

ABSTRACTWith the development of steel structures, a new type of high performance structural steel named by Q460GJ has been increasingly used in the modern steel constructions like the National Stadium of China in Beijing. Q460GJ structural steel is normally used in thick‐walled section members because of the favourable material properties, such as good weldability, low thickness effect on yield strength and low yield ratio. However, only limited knowledge is available on the residual stress distribution of thick‐walled section members fabricated from Q460GJ structural steel. Q460GJ structural steel has different mechanical characteristics and thermal properties from mild steel, both of which influence the formation of residual stress. This indicates that the available residual stress models of mild steel may not be appropriate for Q460GJ high performance steel. In this paper, residual stress in four thick‐walled welded H‐sections fabricated by Q460GJ structural steel were studied by experimental tests. Residual stress were measured by the sectioning method, and the variation of residual stress along steel plate thickness was then determined by slicing method. This study provides the magnitude and distribution of the longitudinal residual stress by both circular curve correction method and straightening measurement method. The effects on plate thickness and the interaction between flanges and webs are explored. Based on the statistical evaluation of the experimental results, a simplified multilayer residual stress model which is expected to use as initial imperfection in column analysis for residual stress in high performance steel is proposed.
13.08: Plastic resistance of U sections under major‐axis bending, shear force and bi‐moments
Authors: Beyer André , Khelil Abdelouahab , Boissonnade Nicolas , Bureau Alain 
Published: September 2017

ABSTRACTEurocode 3 Part 1–1 gives several specific plastic cross‐section interaction equations for I sections. However, the case of U sections is not explicitly addressed. In order to overcome these limitations, an extensive numerical parametric study has been conducted. So as to obtain realistic plastic section resistances, material non‐linear analyses (MNA) have been performed on a numerical model of U‐shaped members modelled with Solid (volume) Finite Elements. In the present paper, the most practical case of U sections subjected to a combination of major‐axis bending, shear force and a bi‐moment (resulting from the torsional load) is treated and a simplified interaction formula is derived. Additionally, it will be shown that the complex torsional behaviour of open cross‐sections leads to a supplementary plastic system for members made of U sections.
13.12: Resistances of I‐ and U‐sections: Combined bending and torsion internal forces
Authors: Baláž I. , Koleková Y. 
Published: September 2017

ABSTRACTInteraction formulae for resistance of cross‐sections under combination of internal forces of bending and torsion. Validity of analytical formulae are verified by two computer programs. Resistances of I‐ and U‐sections under combination of bending moment and bimoment (positive and negative) are investigated for: (i) elastic limit state, (ii) plastic limit state with strengthening, (iii) plastic limit state with strengthening. Simple interaction formulae convenient for standard purposes are presented for both I‐ and U‐sections for plastic resistance without strengthening. For U‐section specially for positive and specially for negative bimoment combined with bending moment.
01.02: Bobtail® bolt preload loss in wind turbine tower prototype: Hammerstein‐Wiener identification model
Authors: Mohammadi Mohammad Reza Shah , Matos Rui , Rebelo Carlos 
Published: September 2017

ABSTRACTNowadays the wind turbines with the high power capacity are installed for the onshore wind parks. In order to achieve higher wind speeds and more stable wind, wind turbine towers are designed for higher altitude. Moreover, higher altitude reduces turbulence and wind shear induced vibrations.The convectional tubular towers are assembled using welded ring flanged joints. Moreover, preloaded bolts are used to connect the segments’ flanges together. Therefore, the fatigue problem is predominant in the tall towers and fatigue failure due to welded connection and/or due to the bolts in tension may be the governing design situation.To tackle the fatigue problem in the bolted joints and discard the welded connections, a new friction connection is designed for tubular segment assembly. The tower segments are designed with long open slotted holes. The preloaded bolts are used to provide contact between the slotted holes and the intermediate auxiliary plate. Therefore, the connection will resist only by the friction in between the plates. In order to provide necessary friction between the plates, sufficient pre‐load should be applied on the bolts. Moreover, it should be guaranteed that the load loss in the bolts is trivial. Therefore, Bobtail® bolt as free maintenance preloaded bolts are used in the friction connections.This paper deals with the identification of a function for bolts load loss behavior in the friction connections and provide an estimation for lifetime loss. A monitoring setup has been settle to measure the load in the bolts and the environmental temperature simultaneously for almost a year. Consequently, the Hammerstein‐Weiner method, was applied to create the nonlinear dynamic model of the friction connection preloading behavior regarding the environmental temperature variation.Furthermore, the identified function output for the measured temperature was compared with the measured force and then the error was calculated. Based on the model, the load loss for constant temperature was calculated for the period of the measurement and was estimated for 20 years of life time span of the structure.The findings demonstrated acceptable amount of load loss in a year and estimation showed that bolts loads retain constant pre‐load after a two years period. Moreover, it is obtained the initial fastening conditions were important to achieve free‐maintenance bolts.
16.23: A comparative analysis of longitudinal stiffener cross‐section for slender I‐girders subjected to patch loading
Authors: Loaiza Nelson , Graciano Carlos , Chacón Rolando , Casanova Euro 
Published: September 2017

ABSTRACTIn the construction of traditional composite bridges whose structure consists of plate girders, the concrete slabs of the decks are often casted before launching. These thin‐walled webs are occasionally reinforced with longitudinal stiffeners to increase bending and shear strengths, and for bridges erected by incremental launching, these stiffeners also provide an enhancement for patch loading resistance. Experimental works have shown that ultimate resistance to patch loading is highly dependent on the size, relative position and shape of the longitudinal stiffener. Nonetheless, a comparison between those three factors should be carried out in order to establish the optimum configuration of longitudinal stiffening for webs under compressive forces. Hence, this study attempts to compare the increase of ultimate strength of a slender I‐girder subjected to concentrated load using open and closed section types of stiffeners, evaluating three different stiffeners configurations: i) a single open section stiffener, ii) multiple open section stiffeners, and iii) a single closed section stiffener. The nonlinear computations were performed using a finite element analysis parametric model, where the relative position and size of the stiffeners are varied to cover a wide range of geometries.