bluuebunny/crossref_metadata_2025 huggingface dataset:
Improvement of the quality of the geodesic support for the reconstruction of the roads
Authors: Penkov V O , Skoryk O O , Uzviieva O M , Yu Panchenko V , Korostelov Ye M
Published: December 2019

Further development of the roadway network in Ukraine will basically take place by modernization, which, in fact, conversion of the system « Road Conditions-Traffic Flow-Environment» from one state to another. Generally, it changes not only the spatial axle position of an existing road, but also the geometric and technological parameters of the road. Modern technological design and construction processes demand higher accuracy and reliability in determining the output spatial parameters measured with survey methods and techniques. Therefore, substantiated higher accuracies and improved survey techniques are tasks of primary importance. They must be solved on the basis of determination of rational error limits in survey works and their influence on the accuracy of building, transport operational and economical parameters of the project and actual engineering structures. The objective of the study is to demonstrate possibilities and efficiency in using various models of the system of ensuring the accuracy in survey works for roadway modernization and for solving other tasks on determination of geometric element parameters of complicated sections on existing roadways.
Theoretical basis of quality assessment of railway technical condition
Authors: Shtompel A M , Korostelov Ye M , Batsamut V M , Olenchenko V T , Horielyshev S A
Published: December 2019

The qualitative performance of the track facility in Ukraine depends upon the technical state of rail track structure, which is determined by correspondence of the characteristics to the current Regulations for laying and maintenance the track on railways of Ukraine. And the parameters indicating the rail track stability directly depend on the carrying capacity of the rail base and the stress-strain behavior.

The rail base consists of elements of various physical and mechanical properties, with its own deformation behavior and stressed state under force loading. Therefore, the stress-strain behavior of the rail base must be evaluated with an appropriate mathematic model showing a flow of forces from one element to another.

The rail track structure operates under the power loading from a train. This load considerably influences operation of the rail track structure and conditions the changes in the technical state in operation. In operation the technical state of the rail track structure is getting worse because the residual deformations accumulated in it, which lead to lower train traffic safety. Nowadays requirements for operational safety of the rail track structure are high, and the problem of evaluation of the stress-strain behavior of the rail base is of great importance.
The design of the length of the route transport stops’ landing pad on streets of the city
Authors: Yu Timkina S , Stepanchuk O V , Bieliatynskyi A A
Published: December 2019

An analysis of the condition and problems of stops of route transport functioning was carried out. The research used theoretical and empirical methods, mathematical modeling for creating a mathematical model of the bandwidth of stopping route transport and the final formalization of the scheme of its operation with and without maneuvering. Analyzing the places of congestion on the street network of the city of Kyiv, we came to the conclusion that one of the reasons for their formation had been insufficient organization of road transport and parking of passenger transport precisely at the locations of stops of route transport. Parameters of stops of route transport and intensity of traffic of public passenger transport have a significant influence on the capacity of city streets and roads. Increasing of the number of vehicles on the city streets, improving their specifications have required a new approach to determining the geometric dimensions of mass transit stops. On the basis of the conducted research, the sizes of the recommended calculated passenger vehicle for the design of elements of public transport stops have been proposed. It is established that when designing stops of route transport, it is necessary to consider the length and width of the calculated vehicle, which are important in determining the area of dynamic and static dimensions of vehicles in the area of the stop. An individual approach shall be taken during the designing of the bus stops on city streets that takes into account the dimensions of the passenger vehicle and allows optimizing the parameters of the boarding and boarding places and thereby reducing the time spent on the bus stop.
Strength calculation of risers near the supports of reinforced concrete three-hinged frames based on the concrete plasticity theory
Authors: Dovzhenko O , Pohribnyi V , Klymenko Ye , Oreškovič M , Maliovana O
Published: December 2019

The necessity of estimation of residual strength of risers sections near supports of reinforced concrete three-hinged frames at their reuse after operation in aggressive environment conditions and damages presence is indicated. The method of calculating the elements strength under the shear on the joint action of the transverse and longitudinal forces based on the plasticity theory is elaborated. The variational method, the virtual velocities principle, discontinuous solutions are applied. The kinematically possible failure schemes, the realization of which depends on the values ratio of transverse and longitudinal forces are proposed. The application boundary of these schemes is defined. The permissible level of concrete class reduction and the degree of its integrity violation were established, under which the residual strength of serial three-hinged frames near the supports was provided.
Increasing the accuracy of definition torsional geometric properties for rolled and welded beams
Authors: Hudz S A , Gasii G M , Hasii O V
Published: December 2019

The features of determining the torsional geometric properties of the cross-section of a steel beam, rolled or composed of three sheets of arbitrary thickness, are considered. When calculating warping properties, it is suggested to take into account the degree of torsional stiffness of the attached structures, that more accurately reflects the actual operation of the fixed beam in the composition of the decking. The differentiated account of rounding at the flange adjacent to the web leads in the rolled profiles to a significant structured increase in the value of the torsional constant. These factors characterize the special conditions of operation of the steel element with complex resistance, that allows determining more precisely the value of internal forces, namely the design bending moments in two planes and the bimoment, which are proportional to the distribution function of the angle of rotation of the rod along its length. It is noted that in fact the bimoment is not only determined by on the load, the elastic bending-torsional constant of the cross-section and the span of the beam, an eccentricity, as well as on the stiffness of the structure that attached to the beam.
Decision-making on quality composition materials exposed to temperature differences
Authors: Afonin V V , Erofeeva I V , Kondrashchenko V I , Emelyanov D V , Fedortsov V A
Published: December 2019

An approach is considered that allows one to make a decision on the choice of compositions of composite materials that have been exposed to temperature changes for a long time. The alternatives are considered – compositions of materials and special criteria, the analysis of which underlies the optimal choice of composition from the group under consideration. Proposed the formation of criteria by which the decision is made to assess the quality of building composite materials. In this article, the criteria are formed on the basis of such properties of building materials as hardness and modulus of elasticity on the surface of the test samples, which were subject to negative and positive temperature extremes. Criteria for each property of the sample are formed on the basis of the given values relative to the starting point of exposure. To make a decision about the quality of composite materials, it is proposed to form three criteria for each of the considered properties of materials. The first criterion is calculated as a change in the corresponding property relative to the initial exposure point. The second criterion is determined sequentially with respect to each exposure point by a change in each of the considered properties. The third criterion is represented as the sum of the first two criteria. After that, some provisions of the ELECTRE methods are applied for ranking the studied compositions of composite materials.
Influence of intermolecular interactions of epoxy binder components on rheological properties and wetting ability
Authors: Barabash E , Popov Yu , Danchenko Yu
Published: December 2019

The purpose of this paper is to evaluate the degree of intermolecular interaction of the surfactant and epoxy oligomer ED-20 molecules and to establish regularities of the influence of this interaction on the rheological properties of the epoxy binder. For that purpose computer modeling and quantum chemical calculations of the interaction parameters of modifying additives with ED-20 have been investigated. For the experimental evaluation of the intermolecular interactions degree of the epoxy oligomer with additives, the viscosity rheological properties and wetting ability of binary mixtures were studied. Result of studies have shown that the higher the intermolecular interaction energy of epoxy binders components is the greater its influence on viscosity and the less they will effect on wetting ability of the binder.
Study of the efficiency of epoxy coating protection of concrete surfaces from sulfuric acid corrosion
Authors: Goncharenko D , Aleinikova A , Kabus O , Kolomiiets Y
Published: December 2019

The application of epoxy coatings to concrete is a method of its protection against sulfuric acid corrosion. The problem of ensuring the efficiency of the coating protection conditioned by many factors is considered herein. Penetration of acidic substances through local defects on the coating surface, which causes its swelling and a sharp increase in the corrosion rate, is one of the main factors. Results of the studies of the samples exposed to 5 % solution of sulfuric acid and to the environment of a sewer system with a high content of hydrogen sulfide in the air are described. It is established that the modification of concrete with additives and the increase of its physical and mechanical properties prevent the stability of the “concrete–epoxy coating” system from increasing. To ensure the reliable operation of reinforced concrete structures in an acidic environment, it is advisable to periodically monitor the condition of coatings in order to identify and to timely eliminate local corrosion.
Acid-basic surface properties of dispersed fillers based on metal oxides TiO2, Al2O3, CaO and Fe2O3
Authors: Danchenko Yu , Andronov V , Barabash E , Rybka E , Khmyrova A
Published: December 2019

The dispersed oxide fillers of different chemical composition were investigated: rutile (TiO2), alumina (Al2O3), calcite (CaO) and hematite (Fe2O3). The mineral composition, surface morphology, particle size and specific surface of the fillers were investigated using modern physicochemical methods. It has been established that the acid-alkaline properties of the active surface centers (ASC) and hydroxyl-hydrate layer (HHL) depend on the chemical and mineral nature of the fillers. It is established that with decreasing acidity of the oxide, the desire for its surface to adsorb water molecules from the air increases. As the alkalinity of the oxide increases, the thickness of both the hydroxyl and hydrate surface layers increases in proportion. It is shown that the acid-alkaline properties of the surface correlate with the acid-alkaline properties of the oxides included in the fillers.
Study of the forming processes of the arbolite structure during the chemical activation of flax shove
Authors: Kazimagomedov I E , Trykoz L V , Kazimagomedov F I , Rachkovskiy A V
Published: December 2019

As one of the ways of directed formation of structures in arbolite (wood concrete), the use of properties of organic additive might serve. A capillary-porous, chemically active material is used for this purpose. The structure of capillaries and pores determines the perspective of directed mass transfer within the “binding substance-additive” system, and the chemical activity of flax shove fibers can replace the physical bonds of the components with stronger ones, the chemical bonds. To determine the ways of modification of the additive, an aqueous solution of calcium sulfate hemihydrate (CaSO4·0.5H2O) was applied along with liquid glass. The substantiation of the chemistry of the processes occurring in the wood-cement compositions during their strengthening was given. Analysis of the dynamics of strengthening of the material has shown that as a result of the chemical activation of flax fibers, the internal structure of capillaries and pores experience colmatage, which inhibits water absorption inside them, and also stronger bonds of flax fibers with cement stone are formed. With the application of the proposed technology, the compressive strength of arbolite increases almost 1.4 times, and the strength under transverse bending increases 1.6 times.
Effect of mineral fillers on the wetting of water-based polymer dispersions
Authors: Saienko N V , Demidov D V , Bikov R A , Younis B N
Published: December 2019

To ensure reliable protection of porous plastered facades, water-based polymer dispersions must meet a set of properties for moisture absorption and vapour permeability. One of the most significant indicators in assessing moisture absorption is the hydrophobic properties of the coating, which characterizes their water repellency. Therefore, the article studied the effect of the dispersed mineral fillers content based on silicates and aluminosilicates on the wetting of water-based polymer dispersions and determined the possibility of their use as decorative and protective materials for plastered building facades finishing. It was found that the studied samples of water-based polymer dispersions can be used as facade coatings with high vapour permeability and low moisture absorption, which is confirmed by studies of the contact angle. The optimum values along the contact angle verge towards the hydrophobic coatings.
Short-term strength of anchor screws on modified acrylic adhesives
Authors: Sklyarov V , Zolotova N , Suprun O
Published: December 2019

Theoretical and experimental studies of the stress-strain state with a short pulling force acting on concrete smooth steel rods with acrylic adhesives were carried out by such scientists as L.N. Shutenko, M.S. Zolotov, B.Yu. Pagi, etc. However, it should be noted that when performing these experimental studies ordinary acrylic adhesive was used. The purpose of the experimental studies was to determine the short-term strength of anchor bolted joints on acrylic adhesives using various modifiers and the depths of bolt insertion. As glue in the manufacture of prototypes of anchor bolted joints, a modified acrylic composition was used. If we accept the strength of the ZnO seal as 100 %, then the strength of the ground mica and methacrylic acid seals differ by 0.35 MPa and 3.5 %, respectively. The results of experiments to determine the strength of anchor bolted joints are systematized depending on the diameter of the anchors and the depth of their embedment in concrete. Based on our studies and analysis of experiments by other researchers, it is recommended that anchoring bolted joints to a depth of l = 8ds.
The effect of the mobility of the concrete mixture on the air content and frost resistance of concrete
Authors: Tolmachov S M , Brazhnik G V , Belichenko O A , Tolmachov D S
Published: December 2019

In the technology of building roads, bridges, buildings and structures, concrete mixtures of different mobility are used. It depends on the complexity of the design, equipment and technical requirements. The main requirement for any product or design is high durability. The main index of durability is frost resistance. To increase the frost resistance of concrete, an additional network of air pores is created. This network is formed through the use of airentraining additives and when the concrete mix is mixed. Different quantity of air may enter in concrete mixes of different mobility. But an increase of the quantity of air involved leads to a decrease of concrete performance. Therefore, it is necessary to know the volume of air bubbles and how they change the properties of concrete. The work shows how the mobility of concrete mixtures affects on the amount of air involved. The results of studies of frost resistance of concrete made from mixtures of different mobility are presented.
Features of studying the efficiency of fire protection of a wooden wall with external exposure to the flame of combustible substances
Authors: Tsapko Y , Bondarenko O , Pinchevska O , Buys’kykh N , Lakida Y
Published: December 2019

The article analyzes the physical ways to provide the necessary limit of fire resistance of wooden structures, which have significant disadvantages, namely, leading to significant material costs and increase the volume of structures. Modern methods of fire protection of building structures are based on the use of blocking coatings, which are complex systems of organic and inorganic components. Studies of the combustibility of wood have shown that a raw specimen of timber construction is capable of engaging and spreading flames on the surface. Instead, the structure treated with the organo-mineral protective coating did not burn after combustion of the model hearth, respectively, and did not break down. The swelling of the protective coating was recorded, and the temperature on the reverse floor was less than 140ºC. As a result, it was ascertained that the effectiveness of the shredded image of the tree’s construction was 4.4 times higher for the protected organic and mineral coatings 3.3 times higher - for the clear protection of non-organic ones. It’s necessary to assimilate a coke ball on the surface of the construction, which will add to the temperature and the temperature glyphine, with which the hour of reaching the boundary temperature will be improved.
Designing and FEM simulation of the helicopter rotor and hub
Authors: Skiba K
Published: December 2019

The paper presents a preliminary design of the three-blade rotor. The geometric model was prepared in the Siemens NX 12.0 programme. After the preparation of the model and kinematic analysis, the structure was checked for strength by means of NX Nastran software. In addition, structural solutions of bearing rotors currently used in the construction of helicopters were discussed and a comparative analysis of the developed rotor design with other rotors was carried out in order to define the basic advantages and disadvantages of each solution. The main rotor of a helicopter is considered the most important component of the rotorcraft, which determines its performance. Rotating blades generate the resultant forces and moments in the rotor hub that allow the helicopter to fly. In the case of a single-rotor helicopter design, a tail rotor must be added to obtain directional control. Cyclic and collective control of blade inclination influences the generation of aerodynamic and inertial loads, which depend on the azimuthal position of the blade on the rotor disc. The number of rotor blades and the properties of the blade-hub connections strongly influence the level of load transfer from the blades through the hub to the helicopter fuselage. By incorporating a set of hinges, it is possible to reduce the component loads of the rotor, tilt and rolling moments transferred to the hull. A conventional articulated rotor head with built-in hinges requires frequent maintenance, which increases helicopter operating costs. Furthermore, a complex structure with a large number of components increases the weight of the articulated rotor.
Computer modelling of automobile engine performance as the source of implications for automobile technology management
Authors: Orynycz O , Tucki K , Wasiak A , Mruk R
Published: December 2019

The need for finding the replacement for fossil fuels causes several technical and technological problems in the engine construction as well as the fuel production and its standardisation. This particularly concerns biofuels. The variety of biological resources and possible conversion routes leads to the multiplication of fuel properties. The regional dependence of biomass resources might cause interregional incompatibility of fuels, which should be avoided. Our previous studies have shown that computer modelling is capable of providing information on the dependence of engine performance upon the type of the fuel used, also under conditions of simulation of road tests. Based on computer simulations of the given engine cycle, the impact of the use of biofuels on carbon dioxide emissions from a diesel and gasoline engine was analysed. The tested fuels were: gasoline 95, diesel, ethanol, DME dimethyl ether, and FAME fatty acid methyl esters. The differences in CO2 emissions of the tested fuels were large (up to 17%), but none of the analysed fuels exceeded the maximum emission limits allowed by legal regulations. The results of such simulations might be used for planning the development of various types of engines -possibly adjustable to fuels of various origin, as well as for planning the fuel composition assuring the best performance in a wide spectrum of engine constructions.
Predictive modelling for air temperature and humidity in a mushroom production process
Authors: Awtoniuk M , Daniun M , Komarchuk D , Syrotyuk S
Published: December 2019

Mushrooms (Agaricus bisporus) are produced in a growing room with a heating, ventilation and air conditioning (HVAC) system. Cultivation is cyclical and consists of several successive phases. Every production phase has different environmental requirements. Microclimate is a system with multiple input signals (e.g. control signals of the solenoid valves of HVAC system) and multiple output signals (compost temperature, air temperature, air relative humidity and carbon dioxide concentration inside the growing room). This paper presents model for prediction for air temperature and air relative humidity inside the mushroom growing room. To determine the dynamic behaviour of the microclimate, the parametric identification method was used. Several models with ARX structures were created. A fit index was chosen to evaluate the quality of models. Finally, optimal prediction horizon for each model was determined.
Recurrence-based diagnostics of rotary systems
Authors: Ambrożkiewicz B , Meier N , Guo Y , Litak G , Georgiadis A
Published: December 2019

Rotary mechanisms are commonly used for transferring rotational movement in diverse industrial applications in mechanical engineering. Components such as gears and rolling bearings have found their purpose in various automotive, machinery or agriculture systems. During operation in mechanisms, they are subjected to defects or changes of their key parameters. This paper considers the application of recurrence plots (RP) and recurrence quantification analysis (RQA) in the detection of teeth crack in a planetary gear system and radial internal clearance (RIC) in a double row self-aligning ball bearing. Raw signals are obtained from accelerometers installed in test rigs. The analysis consists of a statistical analysis approach and calculations of basic RQA parameters i.e. recurrence rate, determinism and length of the longest diagonal. In the paper, we extract information about the fault detection in one of the rotary systems and about bearing operational parameters with nonlinear dynamics identification.
Evaluation of structure stability with the use of remote load
Authors: Molski Szymon , Lonkwic Paweł , Ruta Hubert , Krakowski Tomasz
Published: December 2019

It is a quite common practice to place the load at some distance from the machine restraint. In such a case, it is possible to evaluate the values of stresses and displacements by means of numerical analyses. This article presents the numerical analysis results for the carrying structure of the friction lift power unit with the use of the remote load. The impact of the remote load on the strain of the lift power unit carrying structure is also described. Attention is paid to the places of excessive strain of the structure.
Surface quality simulation with neural networks in AZ91D Mg alloy milling
Authors: Kulisz M , Zagórski I , Korpysa J
Published: December 2019

The mathematical model presented in this paper describes the process of milling AZ91D Mg alloy with the TiAlN-coated tool. The experimental data from the neural network training served to determine the effect of various milling parameters on the surface roughness of the workpiece. The 2D roughness measurements were taken on the end-faces of specimens and focused on the set of three parameters – Ra, Rz and RSm. The tests were performed at constant parameters (tool geometry, workpiece strength properties and technological machine properties), variable parameters (cutting speed, feed per tooth, depth of cut) and output variables (Ra, Rz, Rsm). The simulations were executed by means of the artificial neural networks, modelled with Statistica Neural Network software. Two types of neural networks were employed: MLP (Multilayered Perceptron) and RBF (Radial Basis Function). The comparative analysis showed that the discrepancy between the results of simulation and the results obtained from experimental tests is on an acceptable level, not exceeding 15%. The above result confirms that ANNs can be successfully used as a tool for a selection of technological parameters, enabling obtaining the desired values of surface roughness parameters without the need for time-consuming machining tests.
AI-aided e-nose calibration
Authors: Malec A , Suchorab Z , Guz Ł , Caserta C
Published: December 2019

The development of the semiconductor technology and computer methods contributes to the improvements in measurement techniques of air pollution. Besides traditional techniques of air pollution measurement, such as chromatography or dynamic olfactometry, the electronic nose (EN) is attracting an increasing amount of attention in this area. EN is a device which imitates the human sense of smell. The main component of the device is an array of many non-specific gas sensors. The aim of this article is to present the result of calibration of EN composed of MOS (metal-oxide semiconductor) sensor with the use of the artificial neural networks. For data analysis, linear and artificial intelligence algorithms were employed, whose accuracy was compared.
Modelling the monopedal robot
Authors: Niechciał M , Rybarczyk D , Buśkiewicz J
Published: December 2019

The article describes modelling of the monopedal robot with the application of the numerical method for calculating kinematics. The first part presents a short review of the literature on monopedal robots and the theory of such designs. Due to the complexity of the natural solutions of the bipedal locomotion, the monopedal alternative simplifies the problem, by limiting its scope to the pulse movement in one axis– as required by jumping. In the subsequent part, basic mathematical and kinematic relations connected with a chosen designs. The model was based on a rigid quadrangle driven by a four-bar linkage. The effect was a set of vector equations, required to calculate its kinematics. Due to the complexity of the design, it could not be calculated using traditional analytical methods. The prepared kinematic structure was simulated using the numerical method to give the basis for the future experimental tests. The mathematical model was solved in the Wolphram Mathematica environment. Its main purpose was to analyse the movement of the final link that rests on the ground. The results from the simulation were compared to the movement parameters derived from a model designed in CAD software to verify its correctness. All values of links length and starting angular position, required to calculate the model, were taken from the said CAD project.
Finite element simulations of the bending resistance of square profiles with topological modifications
Authors: Estrada Q , Szwedowicz D , Vergara-Vazquez J , Rodriguez-Mendez A , Silva-Aceves J , Wiebe L C
Published: December 2019

Bending resistance is one of the most important requirements in automobile structural members when lateral crashes occur. For this purpose, the current paper studies the bending and crashworthiness capacity of square profiles with topological modifications. Several finite element simulations were carried out using Abaqus/Explicit software. The topological modifications consisted in combining a square cross-section with polygonal and circular simple cross-sections. In all cases, the profiles evaluated were simulated with mechanical properties for aluminium alloy 6063-T5 with the same mass. The feasibility of our numerical study was validated by a three-point bending tests of a square tube using a Shimadzu universal test machine. Additional to the assessment of complex cross-sections, numerical results for simple cross-sections are presented. A better crashworthiness performance is obtained when the square section of a simple profile is reinforced with topological modifications. According to the simulation results, a complex cross-section can improve the crushing force efficiency up to 77.9% with respect to a single square profile. Regarding cross-sections with topological modifications, the best bending resistance and energy absorption capacity is obtained when the square section is combined with a square profile. This means an increase of 9.2 % of energy absorption (Ea) and 5.67% of CFE respect to the cross-section formed by square and triangular shapes.
Information security risk assessment using the AHP method
Authors: Zaburko J , Szulżyk-Cieplak J
Published: December 2019

This paper is concerned with the issues of cybersecurity and it presents AHP multi-criteria analysis methodology applied for assessing the level of real threats arising from cyberspace that affect the information security. Based on the results of surveys conducted among employees of a selected state institution, we carried out an analysis of awareness of the dangers of cyberspace and ways employees respond to incidents in systems. Taking into account the research results, an appropriate mechanism for the provision of an adequate level of information security was proposed.
A preliminary study on the use of EEMD-RQA algorithms in the detection of degenerative changes in knee joints
Authors: Jonak J , Karpinski R , Machrowska A , Krakowski P , Maciejewski M
Published: December 2019

Degenerative changes, according to world literature, are one of the key reasons for disability, especially in the elderly population. Diagnosis and monitoring of the disease consist mainly in clinical examination, bedside interviews and imaging. However, during the healing process, there is currently no tool for fast, cheap, easily available and diagnostics that would be free from ionising radiation and that would enable evaluation of the course of the disease. Therefore, the scientific community is searching for new diagnostic methods, with the potential for wide application in medicine. Registration and analysis of knee joint vibration signals presents a chance for more accurate and faster diagnostics. The method is capable of detecting damage at an early stage, while specifying the selection of optimal treatment methods. Therefore, it seems crucial to develop methods of analysis appropriate for the nature of tested signals. The quality of low-frequency natural waveforms can be improved by filtration in selected bands, eliminating existing artefacts. This paper presents an application of the EEMD-RQA algorithm in the detection of degenerative changes in knee joints. Pre-processing in the form of filtration gives the opportunity to pre-test the usefulness of the algorithm RQA in the ability to create/subsequent development of indicators describing the condition of the joint surfaces examined without the need for surgical intervention.
Life cycle assessment of the use of sewage sludge as Portland cement replacement
Authors: Pavlík Z , Pavlíková M , Záleská M , Łagód G , Suchorab Z , Guz L
Published: December 2019

In this paper, we proposed an alternative thermal treatment of sewage sludge, aimed at its application in blended cements, which can reduce the energy demands and requires less technologically sophisticated processing. The life cycle assessment (LCA) was performed to quantify the environmental impact of the sewage sludge used as a partial cement replacement. The LCA was focused on the CO2 emission and energy consumption. The functional unit of 1 m3 of blended mortars composed of Portland cement CEM I 42.5, silica sand, and thermally treated sewage sludge, where the sludge was used as partial cement substitute in a dosage of 10, 20, and 30% by mass of cement, was analyzed. The positive effect of the use of sewage sludge as a partial cement replacement with respect to the energy consumption and GHG emission, considering the compressive strength of the analyzed composites, was quite apparent. The decrease of energy consumption necessary for the production of the analyzed blended binders was nearly 10% per each 10% of sewage sludge used as Portland cement replacement. The energy needed for the sludge thermal treatment at 700°C was 220 MJ/t. The emission of GHG related to the sludge thermal treatment was 40kg/t. The presented data were strongly affected by the applied distribution of electricity sources, with a high share of coal combustion plants.
Life Cycle Assessment as a tool for the selection of solar hot water system
Authors: Żelazna A , Gołębiowska J
Published: December 2019

During the past decades, solar hot water systems became a popular solution, enabling utilisation of renewable energy by both, single users and enterprises. Maximisation of the energy gains is one of the factors influencing the environmental burdens connected with solar systems. The second important issue is a kind of elements of system, their production, transportation, usage and disposal. Therefore, as the method for estimation of the scale of environmental indicators Life Cycle Assessment should be used. In this study, LCA was applied for the selection of the individual design on the basis of two criteria (water tank capacity and hot water demand) considered in three system scenarios. The calculated indicators included greenhouse gas emission (Global Warming Potential) and IMPACT2002+ method. The results show the importance of proper designing in the case of environmental impact reduction.
Effect of Mn on microstructure and properties of Cu-12Al powder metallurgy alloy
Authors: Zhang Guofei , Yin Haiqing , Zhang Cong , Deng Zhenghua , Zhang Ruijie , Jiang Xue , Qu Xuanhui
Published: December 2019

Cu-12Al-xMn (x = 0, 1, 2, 3, 4%, mass fraction) alloys were produced using powder metallurgy to investigate the effect of Mn content on the alloy’s microstructure and mechanical properties. The Cu-12Al (no Mn) and Cu-12Al-1Mn (1 wt% Mn) alloys consisted of the α + γ phases, where the size of the α grains in the Cu-12Al-1Mn alloy are much larger. Mn effectively inhibited the eutectoid transformation at a concentration above 1 wt%. Furthermore, the β phase was converted to the β′-martensite phase, which had a monoclinic structure after slow cooling. The phases of the alloy changed from the α + γ phases to the α + β′ + γ phases with the further addition of Mn, and the tensile strength of the 3 wt% Mn alloy was 380.59 MPa. The addition of Mn did not have a significant effect on the density of the alloy.
Microwave toroidal dipolar response in an asymmetric planar metamaterial
Authors: Guo Linyan , Huang Xiaojun , Zhang Qisheng , Guo Minjie
Published: December 2019

Toroidal multipoles are the third type of multipoles which are fundamentally different from conventional electric multipoles and magnetic multipoles. The implementation of toroidal multipoles is hard since its energy is too low to be discovered. This paper proposes a simple planar metamaterial to achieve an often ignored toroidal dipolar response in the microwave band. The metamaterial is designed with a special asymmetric arrangement of asymmetric U-ring resonators to attain a toroidal resonance with high quality factor at 13.5 GHz. Its toroidal nature can be verified by calculated scattered power by multipoles, magnetic field and the surface current. The presented planar metamaterial owns toroidal resonance with high quality factor and it can be applied in the field of antennas, photonics, sensing and energy.
The influence of ZrO2promoter in Pd/fCNDs-ZrO2catalyst towards alcohol fuel electrooxidation in alkaline media
Authors: Gwebu Sandile Surprise , Maxakato Nobanathi Wendy
Published: December 2019

The severe corrosion of carbon supports has attracted the development of ceramic-based support materials. Non-precious metal oxides are potential support materials for fuel cells owing to their corrosion resistance under the harsh fuel cell environment. However, they cannot be used as primary support materials because they are not good electric conductors. In this study, we demonstrate that Pd nanoparticles supported on NaOH-functionalized carbon nanodots blended with zirconium dioxide can act as stable and electroactive anode catalysts for alkaline direct alcohol fuel cells (ADAFC). The Pd/fCNDs-ZrO2electrocatalyst was synthesized by a sonochemical method and characterized by x-ray diffraction (XRD) and transmission electron microscopy (TEM). Cyclic voltammetry (CV) and chronoamperometry (CA) were used to study the electrochemical activity and stability of the Pd/fCNDs-ZrO2catalyst towards methanol and ethanol oxidation in alkaline media. The observed results revealed that the Pd/fCNDs-ZrO2catalyst exhibits higher current densities (12.5 mA cm−2for ethanol and 20.05 mA cm−2for methanol) and lower poisoning rates compared to the Pd/fCNDs and commercial Pd/C catalysts.
Positive Ricci curvature on simply-connected manifolds with cohomogeneity-two torus actions
Authors: Corro Diego , Galaz-García Fernando
Published: December 2019

We show that for each

n
⩾
1

n\geqslant 1

, there exist infinitely many spin and non-spin diffeomorphism types of closed, smooth, simply-connected

(
n
+
4
)

(n+4)

-manifolds with a smooth, effective action of a torus

T

n
+
2

T^{n+2}

and a metric of positive Ricci curvature invariant under a

T

n

T^{n}

-subgroup of

T

n
+
2

T^{n+2}

. As an application, we show that every closed, smooth, simply-connected

5
5

- and

6
6

-manifold admitting a smooth, effective torus action of cohomogeneity two supports metrics with positive Ricci curvature invariant under a circle or

T
2

T^2

-action, respectively.
The Background to Riggs v. Palmer
Authors: Meyer William B
Published: December 2019

The decision of the New York Court of Appeals in Riggs v. Palmer (1889) is remarkable for the mass of discussion about a variety of fundamental issues that it has generated. Elmer Palmer was convicted of murdering his grandfather Francis, and the court refused to let him inherit under Francis’s will despite the absence of any explicit statutory grounds for voiding the legacy. An exercise in legal archaeology uncovering details that are stated only obliquely (or not at all) in the majority and dissenting opinions corrects a number of errors often made about the case. More speculatively, it suggests a new explanation of the result, one supported by a review of similar cases in other states in the same era and of the composition of the Court of Appeals in 1889: that the decision in Riggs is best understood as an ad hominem one, provoked by the unusually light punishment that Elmer had received for his crime and rationalized by an appeal to legal principles. If it was, much of what has been written about the decision and its significance is called into question.
CRISPR/Cas9 for development of disease resistance in plants: recent progress, limitations and future prospects
Authors: Ahmad Shakeel , Wei Xiangjin , Sheng Zhonghua , Hu Peisong , Tang Shaoqing
Published: December 2019

Several plant pathogens severely affect crop yield and quality, thereby threatening global food security. In order to cope with this challenge, genetic improvement of plant disease resistance is required for sustainable agricultural production, for which conventional breeding is unlikely to do enough. Luckily, genome editing systems that particularly clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (CRISPR/Cas9) has revolutionized crop improvement by enabling robust and precise targeted genome modifications. It paves the way towards new methods for genetic improvement of plant disease resistance and accelerates resistance breeding. In this review, the challenges, limitations and prospects for conventional breeding and the applications of CRISPR/Cas9 system for the development of transgene-free disease-resistant crops are discussed.
CGLFold: a contact-assistedde novoprotein structure prediction using global exploration and loop perturbation sampling algorithm
Authors: Liu Jun , Zhou Xiao-Gen , Zhang Yang , Zhang Gui-Jun
Published: December 2019

Motivation

Regions that connect secondary structure elements in a protein are known as loops, whose slight change will produce dramatic effect on the entire topology. This study investigates whether the accuracy of protein structure prediction can be improved using a loop-specific sampling strategy.

Results

A novel de novo protein structure prediction method that combines global exploration and loop perturbation is proposed in this study. In the global exploration phase, the fragment recombination and assembly are used to explore the massive conformational space and generate native-like topology. In the loop perturbation phase, a loop-specific local perturbation model is designed to improve the accuracy of the conformation and is solved by differential evolution algorithm. These two phases enable a cooperation between global exploration and local exploitation. The filtered contact information is used to construct the conformation selection model for guiding the sampling. The proposed CGLFold is tested on 145 benchmark proteins, 14 free modeling (FM) targets of CASP13 and 29 FM targets of CASP12. The experimental results show that the loop-specific local perturbation can increase the structure diversity and success rate of conformational update and gradually improve conformation accuracy. CGLFold obtains template modeling score ≥ 0.5 models on 95 standard test proteins, 7 FM targets of CASP13 and 9 FM targets of CASP12.

Availability and implementation

The source code and executable versions are freely available at https://github.com/iobio-zjut/CGLFold.

Supplementary information

Supplementary data are available at Bioinformatics online.
A new method for measuring the size of nematodes using image processing
Authors: Andrews David G H
Published: December 2019

Many studies have been made on nematodes, especially Caenorhabditis Elegans, which are used as a model organism. In many studies, the size of the nematode is important. This article describes a method of measuring the length, volume and surface area of nematodes from photographs. The method uses the imaging software ImageJ, which is in the public domain. Two macros are described. The first converts the images into binary form, and the second uses several built-in functions to measure the length of the worm and its diameter along its length. If it is assumed that the worm has a circular cross-section, then the volume and surface area of the nematode can be calculated. This is a cheap and easy technique.
Bezlotoxumab for the Prevention of Recurrent Clostridioides difficile Infection: 12-Month Observational Data From the Randomized Phase III Trial, MODIFY II
Authors: Goldstein Ellie J C , Citron Diane M , Gerding Dale N , Wilcox Mark H , Gabryelski Lori , Pedley Alison , Zeng Zhen , Dorr Mary Beth
Published: December 2019

From Monoclonal Antibodies for C. difficile Therapy II, no participants (n = 0/69) with a sustained clinical cure through 12 weeks following bezlotoxumab infusion experienced recurrent Clostridioides difficile infection (rCDI) after 9 months (versus actoxumab + bezlotoxumab, n = 2/65; versus placebo, n = 1/34). Bezlotoxumab’s efficacy appears to be due to prevention rather than delayed onset of rCDI.

Clinical Trials Registration. NCT01513239.
A Novel Lineage of Ceftriaxone-resistant Salmonella Typhi From India That Is Closely Related to XDR S. Typhi Found in Pakistan
Authors: Sah Ranjit , Donovan Suzanne , Seth-Smith Helena M B , Bloemberg Guido , Wüthrich Daniel , Stephan Roger , Kataria Sushila , Kumar Mahadevan , Singla Sonam , Deswal Vikas , Kaur Amarjeet , Neumayr Andreas , Hinic Vladimira , Egli Adrian , Kuenzli Esther
Published: December 2019

Two MDR Salmonella Typhi isolates from India were found by whole genome sequencing to be closely related to the 2016 XDR S. Typhi outbreak strain from Pakistan. The Indian isolates have no chromosomal antimicrobial resistance cassette but carry the IncY plasmid p60006. Both isolates are susceptible to chloramphenicol, azithromycin, and carbapenems.
Low renesting propensity and reproductive success make renesting unproductive for the threatened Piping Plover (Charadrius melodus)
Authors: Swift Rose J , Anteau Michael J , Ring Megan M , Toy Dustin L , Sherfy Mark H
Published: December 2019

Upon reproductive failure, many bird species make a secondary attempt at nesting (hereafter, “renesting”). Renesting may be an effective strategy to maximize current and lifetime reproductive success, but individuals face uncertainty in the probability of success because reproductive attempts initiated later in the breeding season often have reduced nest, pre-fledging, and post-fledging brood survival. We evaluated renesting propensity, renesting intervals, and renest reproductive success of Piping Plovers (Charadrius melodus) by following 1,922 nests and 1,785 unique breeding adults from 2014 to 2016 in the Northern Great Plains of the United States. The apparent renesting rate for individuals was 25% for reproductive attempts that failed in the nest stage (egg laying and incubation) and only 1.2% for reproductive attempts when broods were lost. Renesting propensity declined if reproductive attempts failed during the brood-rearing stage, nests were depredated, reproductive failure occurred later in the breeding season, or individuals had previously renested that year. Additionally, plovers that nested on reservoirs were less likely to renest compared to other habitats. Renesting intervals declined when individuals had not already renested, were after-second-year adults without known prior breeding experience, and moved short distances between nest attempts. Renesting intervals also decreased if the attempt failed later in the season. Overall, reproductive success and daily nest survival were lower for renests than first nests throughout the breeding season. Furthermore, renests on reservoirs had reduced apparent reproductive success and daily nest survival unless the predicted amount of habitat on reservoirs increased within the breeding season. Our results provide important demographic measures for this threatened species and suggest that predation- and water-management strategies that maximize success of early nests would be more likely to increase productivity. Altogether, renesting appears to be an unproductive reproductive strategy to replace lost reproductive attempts for Piping Plovers breeding in the Northern Great Plains.