bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical nano-agents in the second near-infrared window for biomedical applications
Authors: Cai Yu , Wei Zheng , Song Chuanhui , Tang Chuanchao , Han Wei , Dong Xiaochen
Published: November 2018

This review summarizes the recent advances of optical nano-agents for various biomedical applications in the NIR-II window.
A supramolecular Cd(ii)-metallogel: an efficient semiconductive electronic device
Authors: Dhibar Subhendu , Dey Arka , Majumdar Santanu , Ghosh Debasish , Mandal Amit , Ray Partha Pratim , Dey Biswajit
Published: November 2018

A supramolecular Cd(ii)-metallogel with oxalic acid in DMF medium has been achieved, and the semi-conductive characteristics such as the Schottky barrier diode nature of the metallogel were explored.
Efficacy of shape-monitored reduced graphene oxide–copper nanohybrids: anti-bacterial attributes for food safety and dye degradation studies
Authors: Maiti Moumita , Sarkar Manas , Maiti Soumen , Liu Donghong
Published: November 2018

Usage perspective of morphology tailored reduced graphene oxide–copper hybrids is explored as antimicrobial and catalytic agent.
Supramolecular self-assemblies of inverted cucurbit[7]uril with biogenic amines
Authors: Shan Pei-Hui , Zhang Zhi-Rui , Bai Dong , Bian Bing , Tao Zhu , Xiao Xin
Published: November 2018

The binding interactions between six biogenic amine guests and the iQ[7] host were investigated. The experimental results have revealed that iQ[7] shows strong binding affinity towards five of the studied biogenic amines, but not histamine, and that the binding sites are different depending on the structure of the biogenic amine.
Scalable synthesis of a foam-like FeS2 nanostructure by a solution combustion–sulfurization process for high-capacity sodium-ion batteries
Authors: Hu Rudan , Zhao Hongan , Zhang Jianli , Liang Qinghua , Wang Yining , Guo Bailing , Dangol Raksha , Zheng Yun , Yan Qingyu , Zhu Junwu
Published: November 2018

A scalable synthesized foam-like FeS2 nanostructure with an interconnected skeleton that is composed of small particles is used for high-capacity sodium-ion batteries.
A comparative study of pomegranate Sb@C yolk–shell microspheres as Li and Na-ion battery anodes
Authors: Song Junhua , Xiao Dongdong , Jia Haiping , Zhu Guomin , Engelhard Mark , Xiao Biwei , Feng Shuo , Li Dongsheng , Reed David , Sprenkle Vincent L. , Lin Yuehe , Li Xiaolin
Published: November 2018

A high-packing density pomegranate Sb@C yolk–shell structure has been developed as high-performance anodes for lithium-ion and sodium-ion batteries.
Facile fabrication of configuration controllable self-assembled Al nanostructures as UV SERS substrates
Authors: Su Dong , Jiang Shenglin , Yu Muni , Zhang Guangzu , Liu Huan , Li Ming-Yu
Published: November 2018

The resonantly enhanced near-surface electromagnetic field of Al nanostructures (NSs) excited with UV light offers an effective and precise approach to obtain vibration information in complex mixtures up to a single-molecule magnitude.
Synthesis of 2-substituted benzo[b]thiophenes via gold(i)–NHC-catalyzed cyclization of 2-alkynyl thioanisoles
Authors: Dillon Christopher C. , Keophimphone Bagieng , Sanchez Melissa , Kaur Parveen , Muchalski Hubert
Published: November 2018

Efficient synthesis of benzo[b]thiophenes from 2-alkynyl thioanisoles catalyzed by a gold(i)–IPr hydroxide and co-catalyzed by acetic acid.
Copper-catalyzed synthesis of 2,2,2-trifluoroethyl selenoethers and their insecticidal activities
Authors: Dong Jingnan , Li Zhengyu , Weng Zhiqiang
Published: November 2018

A copper-catalyzed synthesis of aryl or alkyl 2,2,2-trifluoroethyl selenoethers was developed. Some of them exhibited promising insecticidal activities against tetranychus cinnabarinus.
The long and the short of polymer grafting
Authors: Michalek Lukas , Mundsinger Kai , Barner-Kowollik Christopher , Barner Leonie
Published: November 2018

Polymer chains are grafted depending on their size onto solid interfaces, leading to a distortion of the surface grafted size distribution. We herein predict and quanitify this distortion effect, which has critical consequences for functional polymer interface design.
Electrokinetic droplet transport from electroosmosis to electrophoresis
Authors: Bazarenko Andrei , Sega Marcello
Published: November 2018

Droplet transport in microfluidic channels by electrically induced flows often entails the simultaneous presence of electroosmosis and electrophoresis.
pH-Induced reorientation of cytochrome c on silica nanoparticles
Authors: Meissner Jens , Wu Yao , Jestin Jacques , Shelton William A. , Findenegg Gerhard H. , Bharti Bhuvnesh
Published: November 2018

The orientation of ellipsoidal cytochrome c molecules at the surface of silica nanoparticles was studied in a wide pH range by combining small-angle neutron scattering, adsorption measurements, and molecular dynamics simulations.
Method and VLSI implementation of lossy‐to‐lossless LTM ECG compression framework
Authors: Zhu Huaiyu , Pan Yun , Li Ke , Huan Ruohong
Published: November 2018

A lossy‐to‐lossless compression framework for electrocardiogram (ECG) signals is proposed for wearable monitoring devices. In this framework, the tail bits of the coefficients generated by the lifting discrete wavelet transform of the ECG sequences are truncated at different levels configured according to the tolerance of the information loss, while no truncation for lossless compression. These processed coefficients are then encoded with the modified run length code. The algorithm is evaluated by the MIT‐BIH arrhythmia database, where the experimental results show that the proposed framework achieves a better comprehensive performance than existing state‐of‐the‐art lossy‐to‐lossless compression approaches. The authors further demonstrate a three‐stage pipeline very large scale integration (VLSI) implementation of the compression framework, which can be used as an intellectual property core with a core area of 0.4 mm2 and achieves power consumption of 1.524 μW at 360 Hz in a 0.18 μm CMOS technology.
Adaptive frequency sampling using linear Bayesian vector fitting
Authors: De Ridder S. , Deschrijver D. , Spina D. , Dhaene T. , Vande Ginste D.
Published: November 2018

The authors present a novel Bayesian approach to adaptively select frequency samples to obtain a rational macromodel of device responses over a broad frequency range while performing as few electromagnetic simulations as possible. The method leverages a Bayesian approach to vector fitting to construct a data‐driven uncertainty measure. The presented technique is demonstrated by application to a double semi‐circular patch antenna and is shown to accurately and efficiently construct a rational macromodel over the frequency range of interest.
Distributed control based power sharing strategy for an islanded AC microgrid
Authors: Negi Nandini , Sahoo Soumya Ranjan , Chakrabarti Saikat
Published: November 2018

This study presents a novel secondary control strategy for a radial microgrid with end‐to‐end distributed energy resource (DER) interconnections, operating under islanded conditions. The control strategy utilises sparse communication and precludes the presence of a centralised controller. The distributed algorithm has a twofold objective. The first task is to determine the desired power injection at each DER bus for a load change occurring anywhere in the microgrid. The remaining task includes obtaining the bus angle set points at all the DER units such that the actual power injections converge to the desired power injections at each DER bus. The algorithm enables accurate system wide power injection in proportion to the respective DER base ratings. The control strategy is tested on a three‐bus, three‐DER system with local loads. The controller is shown to work for two different sets of microgrid ratings. The bounds are evaluated for each design parameter specified according to the system nominal ratings to maintain the stability of the distributed algorithm. Proofs are stated to show the convergence of algorithms to the correct power injection solution for all the nodes. Real‐time simulation results are presented to corroborate accurate power sharing through the algorithm.
System state model based multi‐period robust generation, transmission, and demand side resource co‐optimisation planning
Authors: Dai Chenxi , Wu Lei , Zeng Bo , Liu Cong
Published: November 2018

This study discusses a multi‐period co‐optimised generation and transmission expansion planning (GTEP) problem while considering a proliferation of demand side resources (DSR). Uncertain renewable energy variations and load fluctuations in the long‐term planning horizon are addressed, and a system state model derived via k‐means clustering algorithm is adopted to capture temporal operation features. The problem is formulated as a two‐stage robust optimisation model with mixed‐integer recourse, in which annual investment decisions of generation, transmission, and DSR assets are determined in the first stage and short‐term operation decisions of individual system states are made in the second stage. In recognising that considering DSR deployment and the system state model brings significant computational complexity, an extended column‐and‐constraint‐generation algorithm is adopted to effectively solve the proposed planning problem. Numerical studies show that integrating DSRs into multi‐period GTEP could effectively postpone or even avoid expensive generation/transmission investment in the planning stage, and improve economic efficiency in the operation stage.
Investigation and damping of low‐frequency oscillations of stochastic solar penetrated power system by optimal dual UPFC
Authors: Nahak Narayan , Mallick Ranjan Kumar
Published: November 2018

Solar power being stochastic and asynchronous in nature, its integration with conventional power generation has so many challenges in damping of low‐frequency oscillations. This study presents an investigation of low‐frequency oscillation and damping of stochastic solar power integrated power system by a unified power flow controller (UPFC)‐based dual optimal controller, which gains are optimised by a novel hybrid particle swarm optimisation and improved grey wolf optimiser. The dual controller simultaneously controls the modulation index of series and phase angle of shunt converters of UPFC, which co‐operate with each other, optimising its efficacy and thereby implementing the advantages of both static synchronous series compensator and static synchronous compensator. A detailed Eigen value analysis has been performed with time domain simulations to study the damped oscillatory response of variable and random solar penetration with a power system along with the interaction of solar power with variable synchronous power generations. For a multi‐machine system, a multi‐input single output dual controller is proposed. A maximum sensor and time delay have been considered to design the controller providing a realistic approach. It is observed that random and heavy solar penetration has a more detrimental effect on system oscillations, which can be damped heavily with the proposed controller, in contrast to particle swarm optimisation, differential evolution, grey wolf optimiser, differential evolution particle swarm optimisation optimised lead‐lag and dual controllers.
Synthesis and magnetic properties of Fe‐doped CdS nanorods
Authors: Li Xiaoyan , Deng Minlong , Wang Xue , Li Hongfang , Yu Miao
Published: November 2018

Hexagonal CdS and Fe‐doped CdS nanorods were synthesised by a facile hydrothermal method and characterised by X‐ray diffraction, energy dispersive X‐ray spectroscopy, UV–vis absorption, photoluminescence, and X‐ray photoelectron spectroscopy. The magnetic properties of undoped and Fe‐doped CdS nanorods were investigated at room temperature. The experimental results demonstrate that the ferromagnetism of the Fe‐doped CdS nanorods differs from that of the undoped CdS nanorods. The remanence magnetisation (Mr) and the coercive field (Hc) of the Fe‐doped CdS nanorods were 4.9 × 10−3 emu/g and 270.6 Oe, respectively, while photoluminescence properties were not influenced by doping. First‐principle calculations show that the ferromagnetism in Fe‐doped CdS nanocrystal arose not only from the Fe dopants but also from the Cd vacancies, although the main contribution was due to the Fe dopants.
Cube‐like LaFeO3 microstructures synthesised by a hydrothermal method and their optical properties
Authors: Tong Fan , Zhao Ye , Wang Mao‐Hua
Published: November 2018

The orthorhombic structure of Lanthanum orthoferrite (LaFeO3) was synthesised by a facile hydrothermal method. The hydrothermal reaction time and potassium hydroxide (KOH) concentration play an important role in the formation of LaFeO3 microcubes. The obtained samples were characterised by several analysis techniques such as X‐ray diffraction, scanning electron microscope, ultraviolet–visible (UV–vis) absorption spectroscopy, and photoluminescence (PL) emission spectroscopy for identifying their structural and optical characteristics. On the basis of experimental results, it can be concluded that the obtained samples have been structurally characterised which confirms the orthorhombic LaFeO3 structure. Meanwhile, the results depict that highly pure and monodisperse LaFeO3 microcubes are successfully obtained when synthesised at the alkaline source of 4.5 g KOH and maintained at 240°C for 16 h, which have an average diameter of ∼7 μm. The subsequent plausible formation mechanism of the LaFeO3 microstructure has been explained on the basis of the Ostwald ripening process. Subsequently, the optical properties of the prepared sample were investigated and optimised, and the UV–vis data showed that the microstructure was a visible light absorbing semiconductor with a narrow bandgap. In addition, PL spectra indicate that the LaFeO3 microcubes synthesised by this technique can be considered as a photocatalytic material.
Intensity contrast of solar plage as a function of magnetic flux at high spatial resolution
Authors: Kahil F. , Riethmüller T. L. , Solanki S. K.
Published: November 2018

Magnetic elements have an intensity contrast that depends on the type of region they are located in (for example quiet Sun, or active region plage). Observed values also depend on the spatial resolution of the data. Here we investigate the contrast-magnetic field dependence in active region plage observed near disk center with SUNRISE during its second flight in 2013. The wavelengths under study range from the visible at 525 nm to the near ultraviolet (NUV) at 300 nm and 397 nm. We use quasi-simultaneous spectropolarimetric and photometric data from the Imaging Magnetograph eXperiment (IMaX) and the Sunrise Filter Imager (SuFI), respectively. We find that in all wavelength bands, the contrast exhibits a qualitatively similar dependence on the line-of-sight magnetic field, BLOS, as found in the quiet Sun, with the exception of the continuum at 525 nm. There, the contrast of plage magnetic elements peaks for intermediate values of BLOS and decreases at higher field strengths. By comparison, the contrast of magnetic elements in the quiet Sun saturates at its maximum value at large BLOS. We find that the explanation of the turnover in contrast in terms of the effect of finite spatial resolution of the data is incorrect with the evidence provided by the high-spatial resolution SUNRISE data, as the plage magnetic elements are larger than the quiet Sun magnetic elements and are well-resolved. The turnover comes from the fact that the core pixels of these larger magnetic elements are darker than the quiet Sun. We find that plages reach lower contrast than the quiet Sun at disk center at wavelength bands formed deep in the photosphere, such as the visible continuum and the 300 nm band. This difference decreases with formation height and disappears in the Ca II H core, in agreement with empirical models of magnetic element atmospheres.
Analysis of Vertical Irregularities and Dynamic Forces on the Switch Frogs of the Underground Railway
Authors: Boiko Volodymyr , Molchanov Vitalii , Tverdomed Volodymyr , Oliinyk Olena
Published: November 2018

This article presents the analysis of vertical irregularities and dynamic forces on the switch frogs in operating conditions on the main tracks of Kiev underground railway. For main railways the deterioration problem of tongues, framed rails, switch frogs and as a consequence formation of the character in interaction on the railroad switches is quite widely studied by different scientists, but for conditions of railway underground such researches are practically absent. However, in order to use metal elements of switches rationally and efficiently, the forecast of their service operation and replacement planning, it is necessary to estimate the level of dynamic forces within the most deteriorated elements of switches at different operational stages. This problem is particularly relevant in conditions of financial restriction for track facilities. The studies allowed determining the form, parameters and basic patterns of the irregularities formation in the rolling zone on switch frogs P65 and P50 mark of crossing 1/9 on wooden beams under different operating conditions, which is the basis for determining vertical dynamic forces of interaction within the switch frog subject to setting maximum permissible speeds of movement.
Research of the dependence of pneumatic conveyor compressors power on project parameters of transport machines
Authors: Raksha Sergij , Bohomaz Vladimir , Shcheka Igor , Stefanov Volodymyr , Nesterenko Alex
Published: November 2018

The paper considers the algorithm for calculating the pneumatic transport systems of the main constructions: with high vacuum and with different pressures. The analysis of the dependence of all calculation elements on the design data of the transport system of the considered structures was carried out. In order to accelerate the calculation of such systems, the analytical dependence of the power of the compressor drive on the type of cargo, the coefficient of concentration of the transported mixture, the design productivity, and the geometric parameters of the route, the number and types of auxiliary devices (ells and shutters) are constructed. A graphical analysis of the dependence of compressor drive power of the pneumatic transport systems with high vacuum and with different pressures on the design data: the mixture concentration coefficient, the length of transportation, the design productivity for the transportation of cement with a given route configuration. The directions for further research have been determined.
Ways of introduction of the high-speed movement of passenger trains in Ukraine
Authors: Shevchenko Anna , Matviienko Oleksander , Lyuty Vitalii , Manuylenko Vladimir , Pavliuchenkov Mykhailo
Published: November 2018

The article describes the historical background of the introduction and development of high-speed traffic in the world. The main documents regulating the joint work of high-speed trains of the Commonwealth countries are considered. The main problems of high-speed traffic in Ukraine, and the railway as a whole are studied, analyzed, and described. Recommendations of the company SYSTRA, and the results of developments of Khargiprotrans JSC on the design, implementation and operation of high-speed highways in Ukraine are considered. In conclusion, the current state of the railways, the problems of the current track maintenance has been studied. For Ukraine, first of all, the fourth stage of construction which will connect Lviv with Kiev should be put into operation, based on the analysis of the passenger traffic of the State Committee of Statistics. In this direction, the roadbed and artificial structures are in satisfactory condition. The upper track structure of has sufficient strength. The effect of the profile on the speed of motion is compensated by the power of the locomotive.
Probabilistic evaluation of the railway track infrastructure components failure risk
Authors: Shtompel Anatoliy , Trykoz Liudmyla , Borodin Dmytro , Ismagilov Andrii , Chmuzh Yaroslav
Published: November 2018

The permanent way components are of key importance for safe operation of a rail way. The country regulations, in particular in Ukraine, specify the operational life limits for the permanent way but they do not define any tool or method to predict deterioration of the permanent way condition over time. The study is aimed to develop a method for assessing failure risk of the permanent way components in operation. There was a method offered to evaluate risk of failure of the permanent way components of the welded tracks, which considers accumulated freight load on a rail section. Each element of the permanent way, such as rails, fasteners, sleepers, ballast layer, accumulates defects and deformations. The accumulation rate is different for the above components and depends on freight traffic. There was probability of failure-free operation calculated for each component for the first time and an integral fatigue index of the construction has been offered which considers freight traffic accumulated load. There was a mathematical failure forecast model developed which allows planning of track maintenance. The model allows to take into account operating conditions of a railway section. The results of simulation are presented in various diagrams.
Diagnostics of railway turnout systems using tools of centralization blocking system
Authors: Siroklyn Ivan , Zmii Serhii , Maslii Artem , Buriakovskyi Serhii
Published: November 2018

Turnout systems are one of the few most important components of the railway infrastructure. Recently there has been a revival of research aimed at prognostics and health management of railway turnout systems. The works of the researchers are devoted to evolution timely diagnosis of damage of mechanical components or failures electrical components of switch motor, and contaminated by turnout system. In this article, the approaches of the most common specialized systems of diagnosing and predicting the technical condition of railway turnout systems elements such as POSS, SIDIS W, and APK-DK. The work presented in this article are followed by available approaches and studies of centralization blocking system tools’ informativeness in the field of turnout systems failure diagnostic. The main point of view are methods of engine current analysis. The analysis of the motor current curves of the railway turnout obtained by the experimental method for different values of the ADC operating frequency is presented. Similar current curves are obtained by mathematical modeling of the normal operating mode of the elements of the railway turnout and under the condition of working with developing damage.
Analytic formulas for the natural frequencies of hinged structures with taking into account the dead weight
Authors: Krutii Yurii , Suriyaninov Mykola , Vandynskyi Victor
Published: November 2018

Free bending vibrations of hinged vertical uniform rod with taking into account the dead weight are investigated. The research is based on the exact solution of the partial differential vibration equation with variable coefficients. This approach allows to get more reliable picture of rod’s vibration because only the exact solution carries information of a qualitative nature and forms the most complete picture of the physical phenomenon under consideration. The frequencies equation of problem was written in dimensionless form and the way of its root finding is shown. It has been shown that the problem of determination the nature frequencies of structures is reduced to finding corresponding dimensionless vibration coefficients from equation. The formulas for the first three vibration frequencies of structures were obtained in analytical form. An analytic relationship between the frequencies with and without taking into account the dead weight of the structures was established. The nature of the dependence of frequencies on the value of the longitudinal load was revealed. The presence of conclusive analytical formulas for determining the vibration frequencies of hinged vertical structures with taking into account the dead weight is a real alternative for using the approximate methods for solving this class of problems of solid mechanics.
Peculiarities of calculation and design of slabs on elastic cushion reinforced with non-metallic composite reinforcement
Authors: Luhchenko Olena , Nazhem Ali , Oreshkin Dmitriy
Published: November 2018

Fiber-glass composite reinforcement becomes increasingly popular in different spheres of industry and public economy. Unique technology of the reinforcement production allows receiving the high-quality construction material which complies with modern requirements of liability, quality and safety. Pavlivska Square in Kharkiv may serve as an example of efficient application of non-metallic composite reinforcement for the reinforcement of slabs on elastic cushion during the construction of which the composite grids SKS-100/100 manufactured by Ekipage Technological Group were used as the reinforcement units. Pavement slab reinforcement scheme (including the working draft) was elaborated by the specialists of the Building Constructions Department of O.M. Beketov National University of Urban Economy. The arrangement of the pavement slab of Pavlivska Square was conducted within the short period of time. Due to this, for the purpose of mounting the two-layer reinforcing cage of the slab, the workers of Ekipage Technological Group elaborated a new mounting method which allows the essential reduction of the performance time.
Influence of external and internal cooling at solidification on strength of brittle duralumin in compression
Authors: Semko Oleksandr , Fenko Oleksii , Hasenko Anton , Harkava Olha , Kyrychenko Volodymyr
Published: November 2018

The causes of the occurrence and influence of inherent stresses, unevenly distributed across the cross section, on the strength of materials are analyzed. Methods of creating artificial distribution of inherent stresses with opposite signs in comparison with the usual distribution obtained with natural solidification of the material are given. The sequence of an experiment on cylindrical specimens made of epoxy resin and brittle silicate aluminum alloy in creating distributions of inherent stresses with opposite signs is described. The results of experimental tests of the influence of inherent stresses unevenly distributed across the cross section, on the strength of the epoxy resin and of the fragile silicate aluminum alloy with compression are given. Quantitative characteristics of the influence of unevenly distributed inherent stresses on the strength of materials under compression are obtained. The reasons of the influence of inherent stresses on the strength of materials under compression are analyzed and grounded.
Evaluating the efficiency of the fluidity retention of ready-mix concrete during the transportation of it to the construction site
Authors: Kabus Oleksii , Butska Larisa , Makarenko Olga , Pershina Lidiya , Tymoshchenko Andriy
Published: November 2018

The work is devoted to the study of changes in the time of mobility of concrete mixtures, which are used for commercial concrete with monolithic construction. The in-situ concrete quality depends on the uniformity, viability and workability of the concrete mix intended for the transportation, unloading and workability at the construction site. One of the techniques used for the solution of this problem can be step-by-step addition of chemical admixtures or introduction of setting retarders whose efficiency is expressed in an increased resiliency of the concrete mix that is extended by two and more hours. Each solution has its advantages and drawbacks; therefore the efficiency can only be estimated under specific conditions taking into account the cost of concrete mix and opportunities for the realization of each individual solution. Were received results showing the presence of a problem of mobility loss of concrete mixtures with chemical additives of high water-reducing action. The use of such technological techniques as increasing the initial mobility and gradual introduction of supplements to superplasticizer proved to be effective technological solutions.
Use of liners made of concrete on quartz aggregates and polyurethane composition to reduce vibration, noise and improve the stability of tramway track
Authors: Palant Olena , Plugin Dmytro , Plugin Andrii , Lobiak Alexey , Pluhin Oleksii
Published: November 2018

The theoretical basis of reduction of thermal deformations of the ballastless continuous welded track has been developed. The design of the track with integrated rails has been improved by using a special concrete liner of optimal composition with quartz fillers and aggregates and two-component polyurethane. The method of calculating the concrete composition with optimal strength and coefficient of linear thermal expansion together with optimal structural characteristics, To reduce the temperature stresses in the rails, liners should be made of concrete with quartz fillers and aggregates which provide a reduction of the coefficient of linear thermal expansion αL to 1.1×10-6 K-1. The analysis of the stressstrain state of the rails during heating, performed using the finite element method, has shown that the liners made of concrete with quartz aggregates decrease by 10-32% the temperature stresses in rails. The composition of concrete for liners with the compressive strength of above 60 MPa has been substantiated and the polyurethane composition has been selected for insulation of rails from the channel wall with adhesion to concrete of 0.7 MPa in a dry state, 0.43 MPa in a water-saturated state, and adhesion to steel of 1.2 MPa.
Investigation of the bottom ash slags influence on the heavy concrete frost resistance
Authors: Shulgin Volodymyr , Yermolenko Dmytro , Durachenko Heorhii , Petrash Oleksandr , Demchenko Oksana
Published: November 2018

This paper addresses the issue of the influence of cement consumption, plasticizing additive, and compaction time on the strength and frost resistance of concrete manufactured with bottom ash slags from thermal power plants. The investigation was carried out using the three-factor experiment with variables varied at three levels. There were received response functions, which characterize the correlation between frost resistance and variables: cement consumption, plasticizer additives and compaction time. An analysis of the surface of the response function, where the frost resistance of the concrete was accepted as a response, revealed the optimal correlation between the components of the mixture and the compaction time of the seal. By using the STATISTICA 12 software complex, the values of the factors were specified, when the optimal components ratio with GLENIUM 51 superplasticizer is achieved for the production of concrete with high frost resistance that is greater than F300. The conclusions quantify the results of the investigation.
Traffic conflicts analyses for 2+1 road sections
Authors: Cafiso Salvatore , D'Agostino Carmelo , Bąk Radosław , Kieć Mariusz
Published: November 2018

The additional passing lanes and 2+1 roads improve significant road safety. Studies indicate sections with additional passing lanes (relief or alternately), which may cause reduction in the number of accidents by 50%. However, how geometric design affects the safety performance of such sections is not in depth investigated. Previous studies are carried out with two approaches, i.e. the most often, based on analysis of observed crashes and more rarely by using microsimulation study. In the case of microsimulation research, traffic conflict theory can be applied as a surrogate measure of safety. One of the main problem in simulated conflicts study is the validation of simulation results against real world conditions. The aim of the paper is to assess the reliability of traffic conflict measures obtained by microsimulation against real world observation. Conflicts were detected and classified from video recording and analysis of vehicle trajectories in the merging area on 2+1 roads in Poland. Conducted studies focus only on lane changing conflicts, locations and TTCs values of observed conflicts between vehicles were primarily identified. Observed conflicts are than compared with microsimulated one, to assess if there is a correlation in the two.
Effects of safety barrier life cycle cost factors - identification and analysis
Authors: Kristowski Adam , Grzyl Beata , Gobis Anna , Jeliński Łukasz
Published: November 2018

The costs borne by road infrastructure authorities for managing and maintaining road devices such as safety barriers may be very high. This has prompted the need for identifying and analysing in detail all factors that influence the costs of safety barriers throughout their service life. To meet that need, the authors used international experience and field data collected under the LifeRoSE project to define the cost structure and, as a next step, to analyse factors that are relevant to the costs actually incurred.
Mathematical models as practical tool for road fatalities forecasts on road network in regions
Authors: Wachnicka Joanna
Published: November 2018

The analysis of national data on the number of deaths showed that in Poland from 2010 to 2016 it was possible to reduce the number of fatalities by about 22%. The tendency of changes in the number of fatalities, however, is not homogeneous. When data of individual voivodships is analyzed, the situation is different. The largest reduction in fatalities in the analyzed period of time concerned voivodship Świętokrzyskie, where there was more than 45% drop in the number of fatalities. The following voivodships: Łódzkie, Lubelskie and Podkarpackie recorded a decrease in over 30% of fatalities. Unfortunately, at the end of the classification there were four voivodships with a fall below 8%, and what is disturbing voivodship Lubuskie recorded a nearly 5% increase in the number of fatalities. The current traffic safety management at the level of voivodships is often the implementation of central recommendations, which, as results from the analysis of statistical data, are not equally effective in every province. Therefore, models for forecasting changes in road safety are required. Taking into account local characteristics and implemented actions can be used to manage security more effectively at the regional level. This paper presents examples of the use of mathematical models to predict the number of fatalities in individual voivodships depending on the adopted action scenarios. Regression models were developed, taking into account demographic, infrastructural, economic and automotive factors. It turned out that in individual voivodships, various factors affect the level of road safety on roads differently. Therefore, an individual approach to each voivodship is important in order to reliably forecast the level of security.
Study of technical parameters of experimental traffic signs — results obtained within the frames of RID 4F research project
Authors: Lusa Rafał , Skierczyński Paweł , Kornalewski Leszek , Czyżewski Adam , Rymsza Barbara , Litwin Dariusz
Published: November 2018

This article presents the principles of selection of colours and the thickness of lines during designing of traffic signs, the legal aspects traffic signs must correspond to, test methods used during assessment of both roadway markings and vertical experimental traffic signs, results of studies of those signs and their assessment in the case of possible changes in drivers behaviour.
The use of simulator studies to assess the impact of ITS services on road users behaviour
Authors: Pędzierska Małgorzata , Kamiński Tomasz
Published: November 2018

The subject of this publication is the use of top-of-the-range driving simulators to study the impact of ITS services on the road safety. The aim of the article is to describe the assumptions of simulation studies carried out as part of the RID 4D project and to present the method of building research scenarios. The article discusses the catalogue of ITS services of the greatest importance to the Road Traffic Safety and traffic efficiency developed under the project. Then, services from the catalogue were specified, which were tested on the driving simulator of the Motor Transport Institute. The tests included sections of a dual-lane expressway. As a result of the work, four scenarios were created containing various dangerous events and variable message boards informing drivers about the danger and/or limiting the permitted speed. During the simulation, a set of several dozen parameters related to vehicle motion was recorded, in particular the distance to the vehicle ahead, time to collision with another vehicle or object on the road, speed, intensity of braking and acceleration. The tests were performed for good and bad weather conditions on a 60-person study group. The division into age groups 18-24, 25-50 and above 50 years was applied. The research showed a difference in the way drivers of static signs and speed limits on the variable message signs affect drivers. For variable messages signs, there was a greater decrease in speed than in the case of static signs.
The application of microscopic models in the study of pedestrian traffic
Authors: Oskarbski Jacek , Gumińska Lucyna
Published: November 2018

Cities (especially in Central and Eastern Europe) focus on improving the road network, which aims to improve the efficiency of motor traffic and minimize congestion. Most of existing tools for analysing the effectiveness of urban transport networks do not assume to analyse the impact of walking and cycling on efficiency of transport systems. It is therefore necessary to develop solutions that on the one hand will reduce congestion, and on the other hand, improve the safety and quality of travel of vulnerable road users. One of the tasks to be developed in order to improve pedestrian conditions is to determine the relationship between pedestrian and vehicle traffic. An attempt has been made to establish the relationship between pedestrians and vehicle traffic in order to describe traffic conditions and pedestrian safety at pedestrian crossings. The analyses were based on simulations carried out using the PTV Vissim/Viswalk software and with the use of surrogate safety measures.
Analysis of results of emission parameters of advertising media in field conditions
Authors: Chrzanowicz Marcin , Jaskowski Piotr
Published: November 2018

The lighting parameters of advertising media observed from the road leading drivers are one of the basic factors which should be taken into account in the process of determining the influence of the carrier on the risk related to the possibility of a road event. As a result, exceeding the permissible parameters may lead to disturbance of the vision process or distraction from the driver’s primary objective, which is to observe the road situation. The article presents the results of tests of lighting and geometric parameters carried out on a large number of advertising media located in the vicinity of Polish roads. The study was conducted at night, using an original research procedure. Observation of advertising media from the driver’s position is included. The final result of the work is information about the actual levels of lighting parameters generated by a large group of advertising media of different character of light beam emission (broken down into defined emission groups A - D), which can be observed from the driver's position.
System to support police driver psychological assessment for safety. Project results
Authors: Kuczyńska Ewa , Nowicka Izabela , Grześkowiak Angelika
Published: November 2018

The objective of this article is to present the results of research designed to build a system of support for the psychological assessment of police drivers, including drivers of police emergency vehicles, as required by Polish law. Part of the research and development efforts, the project analyses the world’s most recent research (commercial and non-commercial projects) which is not subject to confidentiality rules. The analysis shows that the project will help to build a functional support system. Based on modern IT technologies and part of the Police’s PDTN network, the system will support the psychological assessment of police drivers, including drivers of police emergency vehicles. The system was implemented in IT network technology and can, as a result, operate directly with the Police Data Transmission Network (central server, access from any PDTN workstation) ensuring independence and security of data collection and storage.
Psychological attentional characteristics based on TEST2DRIVE test battery and age as a factor of drivers distraction in LCT and 3VPT simulator scenarios
Authors: Tarnowski Adam , Szostok Krzysztof
Published: November 2018

Drivers distraction analysis should take into account capabilities of road users with the weakest performance. The first issue was to determine by Test2Drive psychological testing system, empirical criteria of limited attention performance. The second issue was the level of influence of distracting roadside advertisement on driving performance in standard simulator tasks - three vehicle platoon task and lane changing task. The attentional performance has been established by PUT test. This method, based on conjunctive search task was an indicator of speed and accuracy of visual inspection. In the experiment distraction mode has been established at three levels: on roadside billboards red dot has been absent or exposed for 1 or 2 second. In first analysis a group of about 17 000 professional drivers, aged 18-84 form Test2Drive database were selected. In a simulator experiment a group consisted of 30 drivers in age 20-60. As expected, attention performance decreased with age. Markers of impaired attentional performance have been established. In the experiment, no significant effects have been found in 3VPT paradigm. In LCT paradigm, a significant interaction of attention and distraction mode has been observed - drivers with symptoms of attentional malfunctions presented significant problems with maneuver accuracy. The experiment allowed to prove that attentional performance led to higher distraction when stimuli analogical to roadside advertisement were presented. The observed effect was statistically significant but not so strong as in had been expected, what can be explained by a small sample size, in which attention disorders rate were not high. Even with its limitations the experiment proves a simple thesis - roads users with limited attention performance are safer when no salient distractors are disturbing them.
The effective estimation of skid resistance of SMA pavements in relevant aspect of safety and durability of asphalt roads
Authors: Stankiewicz Beata , Slabonski Pawel , Slabonska Emilia
Published: November 2018

The role of skid resistance of road pavements in ensuring safety of road traffic becomes particularly important when such surfaces become moist or wet. The various types of aggregates and special additives play an important role in asphalt mixtures like SMA, because they fill voids in paving mix and improve the cohesion of asphalt binder. The paper presents the evaluation of skid resistance of five kinds of SMA pavements, during exploitation, based on macro-texture and micro-texture comprehensive analysis. Tests were performed on five research pavement sections made from SMA on roads located in the southern part of Poland. SRT 3 equipment and methodology were used to all estimation of pavement roughness. The micro-texture and macro-texture of asphalt surface in pavements evolve under the influence of traffic and synergistic environmental interaction. The experimental parts of SMA pavements were observed in relevant aspect of skid resistance and durability using electronic microscopy type KEYENCE VHX-6000 Digital. The results of evaluation were compared with data from a literature review.
La représentation sociale de la santé des entraîneurs de hockey sur glace au Québec
Authors: Guicherd-Callin Lilian Bernard , Otis Joanne , Potvin Louise
Published: November 2018

L’entraîneur de hockey est un acteur qui peut intervenir dans des actions de promotion de la santé. Son implication dans ce type d’action sera conditionnelle à la représentation sociale de ce groupe sur ce qu’est la santé. L’objectif de l’article est de documenter la représentation sociale (RS) de la santé d’entraîneurs de hockey, documenté et exploité dans le cadre d’un processus de légitimation des savoirs avec Hockey Québec. La méthodologie s’appuie sur un dispositif de triangulation des données obtenues par un questionnaire et des entrevues individuelles. Un échantillon de 330 personnes a répondu au questionnaire et de ce nombre, 12 entraîneurs ont participé aux entrevues. Des analyses catégorielles et prototypiques ont été réalisées sur des associations de mots tirés du questionnaire ainsi qu’une analyse thématique pour les entrevues. L’étude permet de faire ressortir la structure de la RS avec trois conceptions différentes et six dimensions qui offrent des éléments pour juger des opportunités et des limites d’impliquer les entraîneurs de hockey en promotion de la santé. Cette étude offre une nouvelle contribution au débat sur la structure des représentations sociales.
Phase transition for loop representations of quantum spin systems on trees
Authors: Betz Volker , Ehlert Johannes , Lees Benjamin
Published: November 2018

We consider a model of random loops on Galton-Watson trees with an offspring distribution with high expectation. We give the configurations a weighting of θ#loops. For many θ > 1, these models are equivalent to certain quantum spin systems for various choices of the system parameters. We find conditions on the offspring distribution that guarantee the occurrence of a phase transition from finite to infinite loops for the Galton-Watson tree.
A soft x-ray-ultraviolet (SUV) beamline and diffractometer for resonant elastic scattering and ultraviolet-vacuum ultraviolet reflectance at the Singapore synchrotron light source
Authors: Yu X. J. , Diao C. Z. , Venkatesan T. , Breese M. B. H. , Rusydi A.
Published: November 2018

A new beamline and a six-circle UHV diffractometer have been constructed at the Singapore Synchrotron Light Source with a broad energy coverage from 3.5 to 1500 eV. The beamline is optimized for ultraviolet-vacuum-ultraviolet optical reflectivity and resonant soft X-ray scattering with medium energy resolution over a broad energy range, achieved by using a self-focusing monochromator consisting of a plane mirror and three variable line spacing gratings. The unique character of the diffractometer comprises 4-circles in the vertical plane and 2-circles in the horizontal plane. Thirteen motions are available inside the UHV chamber with a base pressure of 1 × 10−9 mbar. Two sample holders working independently over a temperature range of 37 K–400 K are controlled by a closed-cycle cryostat, while the bottom holder inside a high field compact pulsed magnet is available for measurements requiring a magnetic field.
Interatomic potentials for ground and excited states of Ar+He
Authors: Sharma Amit R. , Weeks David E.
Published: November 2018

The potential energy curves (PECs) of the ground and excited states that correlate in the atomic limit with Ar([Ne]3s23p6,1S), Ar([Ne]3s23p54s1, 3P, 1P), and Ar([Ne]3s23p54p1, 3D, 3P, 3S, 1D, 1P, 1S) are calculated at the multireference configuration interaction (MRCI+Q) theoretical level with extrapolations to the complete basis set limit using all-electron correlation consistent triple-, quadruple-, and quintuple-zeta basis sets. Scalar relativistic corrections are calculated using second-order Douglas-Kroll-Hess Hamiltonian with the corresponding basis sets contracted for scalar relativistic Hamiltonians. For these calculations, the 3s orbitals of the Ar atom are not included in the active space but are correlated through single and double excitations. Spin-orbit eigenstates are computed by diagonalizing the Breit-Pauli matrix between internal configurations with no electrons in external orbitals and added to the scalar relativistic results. A total of 32 molecular PECs are computed with spin-orbit contributions, which correlate with 1s1, 1s5−2, and 2p10−1 atomic Ar energies in Paschen notation. Important features of the PECs and system crossings are discussed.