Special Line Research Articles

Implementation of software geogebra on triangles

Mathematics teaching is a learning process gives an understanding of mathematical concepts for students. The basic concepts of mathematics must be embedded well in each student so that understanding concepts at an advanced level can be easily mastered. Mathematics teachers play an important role regarding the problems faced by students when learning mathematics in class. A math teacher in addition to having the ability to master mathematical concepts well, is also required the ability to manage the class so that students can understand the concept well and learning achievement is in the high category. Mathematics is a subject consisting of great ideas that are connected to each other so that understanding cannot be separated because each concept will contribute to the other concepts. Most students still say that mathematics is a difficult and uninteresting lesson, therefore, a teacher needs to apply specific strategies used in the mathematics learning process so that it can change students’ perceptions of mathematics into an interesting and easy lesson. The use of technology can help teachers and students learn mathematics, for example the use of GeoGebra software. GeoGebra software has the benefit of being able to make geometric paintings that are fast and precise compared to using paper and pencil and the existence of animation facilities provides a clear visual experience for students and teachers. One of the geometry concepts is to construct a flat triangle, in this study the discussion is to determine the special lines on the triangle using GeoGebra software and then determine the intersection of the special lines of the triangle.

Welding Seam Trajectory Recognition for Automated Skip Welding Guidance of a Spatially Intermittent Welding Seam Based on Laser Vision Sensor.

To solve the problems of low teaching programming efficiency and poor flexibility in robot welding of complex box girder structures, a method of seam trajectory recognition based on laser scanning displacement sensing was proposed for automated guidance of a welding torch in the skip welding of a spatially intermittent welding seam. Firstly, a laser scanning displacement sensing system for measuring angles adaptively is developed to detect corner features of complex structures. Secondly, a weld trajectory recognition algorithm based on Euclidean distance discrimination is proposed. The algorithm extracts the shape features by constructing the characteristic triangle of the weld trajectory, and then processes the set of shape features by discrete Fourier analysis to solve the feature vector used to describe the shape. Finally, based on the Euclidean distance between the feature vector of the test sample and the class matching library, the class to which the sample belongs is identified to distinguish the weld trajectory. The experimental results show that the classification accuracy rate of four typical spatial discontinuous welds in complex box girder structure is 100%. The overall processing time for weld trajectory detection and classification does not exceed 65 ms. Based on this method, the field test was completed in the folding special container production line. The results show that the system proposed in this paper can accurately identify discontinuous welds during high-speed metal active gas arc welding (MAG) welding with a welding speed of 1.2 m/min, and guide the welding torch to automatically complete the skip welding, which greatly improves the welding manufacturing efficiency and quality stability in the processing of complex box girder components. This method does not require a time-consuming pre-welding teaching programming and visual inspection system calibration, and provides a new technical approach for highly efficient and flexible welding manufacturing of discontinuous welding seams of complex structures, which is expected to be applied to the welding manufacturing of core components in heavy and large industries such as port cranes, large logistics transportation equipment, and rail transit.

Utilization of Coal Gangue Aggregate for Railway Roadbed Construction in Practice

As a massive solid waste, the high value-added utilization of coal gangue has received more and more attention in China. This study focuses on the utilization of coal gangue aggregate in railway engineering for coal transportation passage. Coal gangue aggregate was employed as high-grade railway subgrade filler andprepared concrete for roadbed drainage (named coal gangue roadbed protecting concrete—CGRPC). First, the basic properties of coal gangue such as particle size distribution, ignition loss, strength change under water softening, and compression performance were measured. Then, the technology to use coal gangue as filler in railway subgrade was put forward based on a real engineering application with the Jingang coal-carrying railway special line. Field tests showed that the coal gangue roadbed had excellent performance. The dynamic stiffness expressed as K30 was more 130 MPa/m, which meets the requirement for high-speed railway roadbeds. The distribution of vertical earth pressure according to the backfill depth showed a linear growing tendency. Finally, the technical and economic benefits of using coal gangue railway roadbeds were analyzed. The application of coal gangue near the railway line not only solved the problem of aggregate shortage in engineering construction, but it also consumes the coal gangue waste and leads to huge social benefits.

Development and application of electron beam optical diagnostics for the multi-turn ERL of the Novosibirsk FEL facility

The optical diagnostics system is under development for the multi-turn energy recovery linac (ERL), which is used as a source of electrons for the Novosibirsk free electron laser (FEL) facility. Part of the diagnostic system has already been installed on the last track of the ERL. Its full configuration includes stations for measurement of the transversal and longitudinal electron beam profiles upstream and downstream of the FEL undulators. The stations for measurement of the electron beam energy spread and undulator radiation spectrum are at the stage of installation and commissioning. A radiation power sensor will also be set in the special output radiation line, mounted at an angle to the optical axis of the FEL. The new optical diagnostics is mostly required for fine tuning of the magnet system for electron outcoupling experiments. This paper presents a detailed overview of the new diagnostics and discusses the first results of the transverse beam profile measurements and experiments planned for the near future.

Seed coat anatomy ofCercis chinensisand its relationship to water uptake

The hard seed coat of Cercis chinensis Bunge is an important factor of its dormancy. A study of the characteristics of water absorption is vital for understanding seed dormancy and germination. This investigation found that soaking in water at an initial temperature of 80 °C for 5 min was optimal for breaking the hardness of C. chinensis seeds. Scanning electron microscopy (SEM), dye-tracking, and blocking experiments were used to examine the major water entry sites and the relationship between water uptake and seed coat structure during C. chinensis seed imbibition. The SEM images showed that the seed coat consisted of three layers: epidermis, palisade, and sclereid. Special light line, vascular bundle, and counter-palisade layer structures were found in the side of the hilum. The blocking experiments showed that the hilar region was an important water absorption site because, if the region was not blocked, it showed the highest water absorption when imbibed for 3–12 h. However, all parts of the seed coat can absorb water if enough time is allowed after the seed coat hardness has been broken. The dye-tracking test showed that after 3 h water entered the seed only via the hilum fissure. Therefore, the hilum fissure acts as the initial site of water absorption. When more time was allowed, water moved more rapidly on the side with vascular bundles than on the opposite side.

Determination of the Density and Intensity of Irrigation of Forest Combustible Material before the Combustion Front When Creating an Effective Control Line

The results of experiments on the localization and complete cessation of flame combustion and thermal decomposition of typical forest combustible materials (for example, pine needles and birch leaves) are presented, using a specialized control line before the combustion front in the form of a moistened layer of material with control of its size and retained water volume. Necessary and sufficient conditions for the complete cessation of flame propagation and the pyrolysis front are determined. The relationships between the main parameters are established: the volume of water, the density and intensity of irrigation, the size of the control water strip, and the volume of dry forest combustible material. When summarizing the experimental results, the values of the rational density and intensity of irrigation of forest combustible material before the combustion front are highlighted. The main differences in the selection of the effective values of these parameters are shown in the case of localization and cessation of flame burning and thermal decomposition of needles and leaves.

Magnon Accumulation in Chirally Coupled Magnets.

We report strong chiral coupling between magnons and photons in microwave waveguides that contain chains of small magnets on special lines. Large magnon accumulations at one edge of the chain emerge when exciting the magnets by a phased antenna array. This mechanism holds the promise of new functionalities in nonlinear and quantum magnonics.

Centralized Maintenance Time Prediction Algorithm for Freight Train Wheels Based on Remaining Useful Life Prediction

Many freight trains for special lines have in common the characteristics of a fixed group. Centralized Condition-Based Maintenance (CCBM) of key components, on the same freight train, can reduce maintenance costs and enhance transportation efficiency. To this end, an optimization algorithm based on the nonlinear Wiener process is proposed, for the prediction of the train wheels Remaining Useful Life (RUL) and the centralized maintenance timing. First, Hodrick–Prescott (HP) filtering algorithm is employed to process the raw monitoring data of wheel tread wear, extracting its trend components. Then, a nonlinear Wiener process model is constructed. Model parameters are calculated with a maximum likelihood estimation and the general deterioration parameters of wheel tread wear are obtained. Then, the updating algorithm for the drift coefficient is deduced using Bayesian formula. The online updating of the model is realized, based on individual wheel monitoring data, while a probability density function of individual wheel RUL is obtained. A prediction method of RUL for centralized maintenance is proposed, based on two set thresholds: “maintenance limit” and “the ratio of limit-arriving.” Meanwhile, a CCBM timing prediction algorithm is proposed, based on the expectation distribution of individual wheel RUL. Finally, the model is validated using a 500-day online monitoring data on a fixed group, consisting of 54 freight train cars. The validation result shows that the model can predict the wheels RUL of the train for CCBM. The proposed method can be used to predict the maintenance timing when there is a large number of components under the same working conditions and following the same path of degradation.

Assessment of mutagenized giant reed clones for yield, drought resistance and biomass quality

Given the sterility of giant reed (Arundo donax L.), mutagenesis can be a valid strategy to increase genetic diversity in the species and to enable the selection of superior genotypes with new agronomic and qualitative characteristics. The objective of this study was to evaluate the quantitative and qualitative traits of selected three-year old giant reed mutants (UniBO3; Line10; and Line11). The mutants' performance was evaluated in comparison to the local non-mutagenized ecotype (Arun11) under irrigated and rainfed conditions. Yield differences among mutants were significant: Line11 produced the highest (24 Mg ha−1), and UniBO3 the lowest (19 Mg ha−1) biomass yield, while Line10 showed intermediate yield (22 Mg ha−1). Such variable yields were in line with tiller density and WUE. Besides that, Line11 showed and enhanced plasticity in its water uptake sources and drought resistance. However, the effects of the irrigation and the genotype by irrigation treatment interaction were not significant. The irrigation treatment did not change either the qualitative characteristics of Line11: the cellulose content (42%) was higher than in the control and UniBO3 mutant. Whereas the hemicellulose and lignin contents remained unvaried, suggesting Line11 as a promising feedstock for conversion to advanced biofuels. As for the mineral composition, Line11 showed the most marked changes, especially in terms of K, Si, and Si/K ratio, suggesting a lowered quality for thermochemical conversion. The induced variability shows some promising characteristics that could lead to new specialized mutant lines with improved suitability to specific environmental conditions and conversion technologies.

Mechanistic Study on High Efficiency Deep Blue AIE‐Based Organic Light‐Emitting Diodes by Magneto‐Electroluminescence

AbstractAggregation‐induced emission (AIE) materials are highly attractive because of their excellent properties of high efficiency emission in nondoped organic light‐emitting diodes (OLEDs). Therefore, a deep understanding of the working mechanisms, further improving the electroluminescence (EL) efficiency of the resulting AIE‐based OLEDs, is necessary. Herein, the conversion process from higher energy triplet state (T2) to the lowest singlet state (SS1) is found in OLEDs based on a blue AIE material, 4′‐(4‐(diphenylamino)phenyl)‐5′‐phenyl‐[1,1′:2′,1′′‐terphenyl]‐4‐carbonitrile (TPB‐AC), obviously relating to the device efficiency, by magneto‐EL (MEL) measurements. A special line shape with rise at low field and reduction at high field is observed. The phenomenon is further clarified by theoretical calculations, temperature‐dependent MELs, and transient photoluminescence emission properties. On the basis of the T2‐S1 conversion process, the EL performances of the blue OLEDs based on TPB‐AC are further enhanced by introducing a phosphorescence doping emitter in the emitting layer, which effectively regulates the excitons on TPB‐AC molecules. The maximum external quantum efficiency (EQE) reaches 7.93% and the EQE keeps 7.57% at the luminance of 1000 cd m−2. This work establishes a physical insight for designing high‐performance AIE materials and devices in the future.

Optimization of the technology for the production of foam glass aggregate

The article presents the results of a study of the state of production of a foam glass and the nomencla-ture of its products. It is shown that it is expedient to use the recycled glass obtained from the bottle battle, the defective glass and the double-glazed windows as a raw material for the production of the foam-glass. The re-quirements are formulated for glasses, which should have low viscosity values in the range of foaming tempera-tures. The features of the technology for the production of the foam glass aggregate at the specialized lines are outlined. The technology features are the composition of the charge and temperature conditions of burning. The mixture for the production of the foam glass aggregate consists of glass flour, organomineral blowing agent con-taining water and food glycerin, as distinct from the slab foam glass, where soot or coke is used as a blowing agent. The results confirm the effectiveness of the use of the foam glass aggregate as a soundproofing backfill for floors. Currently, about 70% of the foam glass aggregate is used for roofs and stylobates; the rest is used in landscape design, road construction, foundations and major repair. In the future, the areas of application of the foam glass aggregate can be significantly expanded in the direction of building systems, lightweight aggregates, etc., which involves in-depth studies of the properties of this material.

Triangular Rogue Waves and Multi- Wave Trains Generation in a Chameleon Electrical Transmission Line

In this work, we present a particular nonlinear transmission line called chameleon nonlinear transmission line. In fact, the chameleon’s behavior is related to the fact that without changing its appearance, the line can exhibit alternatively purely right - or left - handed behavior. This transmission line is different to the composite one. So, the goal of this work is to demonstrate that this special line can support the propagation of soliton light pulse subjected to quintic – phase modulation, improve the freak wave’s mechanism of generation and verify the chameleon’s behavior of the line. Consequently, we employ collective coordinate’s theory in order to give a great characterization of the light pulse. Then, we introduce an upgraded function called “type II Ansatz function” with eight collective coordinates compared to the conventional Gaussian Ansatz with six collective coordinates. We show that the two additional coordinates will allow us to improve the technique of measurement of internal excitation leading to the generation of rogue events. Moreover, these coordinates will give supplemental details on frequency shift and chirp distortions during the generation of specific rogue events such as “wall of waves”, tree structures, multi - wave trains, Kuznetsov - Ma breathers, Akhmediev breathers, Peregrine solitons and triangular rogue waves. The stability of the soliton light pulse will be also investigated at specific frequency ranges.

Experimental study of wind impact on multilevel industrial scaffolding

In the article, the local stress-strain state of structures and constructions is investigated, various variants for the design of the boundary are taken into account: special lines, points. The acting forced deformations don’t satisfy the compatibility conditions. They have a finite discontinuity along the contact line (surface) of the domains, including the irregular point of the boundary, causing stresses. The subject of article is stress concentrators the singularity of the stress-strain state of structures and constructions exhibiting “constructive heterogeneity” and discontinuous forced deformations determined on polymer models of photoelasticity and defrosting of deformations. A complex theoretical-numerical-experimental approach, for obtaining and analyzing the stress state in the neighborhood of the irregular point of the plane domain boundary, is proposed to extrapolate reliable experimental data to a domain where the fringe contour is not readable.

Developing a Stand for Evaluating Technical Condition of Volumetric Hydraulic Drives with a Hydraulic Loading Device

Introduction. The article deals with the development of a device for evaluating technical condition on of volumetric hydraulic drives made in Russia and abroad at repair and service centres. Materials and Methods. The study uses the statements of theoretical mechanics and hydrodynamics, the basic principles of mechanisms and machines production. For technical condition evaluating of volumetric hydraulic drives, the method of hydraulic loading of hydraulic motor was applied. Reliability of results was confirmed during experimental settings of the hydraulic loading device stand. Results. A stand design with the hydraulic loading device was developed and put into practice for new technical condition evaluating of volumetric hydraulic drives, made in Russia and abroad, at repair and service centres. A property of the stand is the use of the hydraulic loading method when the torque (braking) moment on the shaft of the tested hydraulic rotor is created using a hydraulic machine. The stand consists of data processing and measurement units. The data processing unit is based on a multifunctional data acquisition board connected with a personal computer. The structure of the data measurement unit includes a frequency converter connected to an electric motor, a drive shaft for connecting the shaft of the tested hydraulic pump; hydraulic system having a hydraulic tank; suction, control, drain, and discharge lines and reversible flow chokes installed in discharge lines and connected with the hydraulic pump and hydraulic rotor; loading device with the reversible hydraulic pump, drive shaft joined with the shaft of the tested hydraulic motor. Additionally, reversible throttle flow meters are connected via special ports and electric lines to the data acquisition board. The developed stand allows evaluating the technical condition of most widespread models of volumetric hydraulic drives used in modern agricultural and road construction equipment. The stand is characterized by good energy efficiency, simplicity of design, low costs, good technical characteristics that make it competitive. Discussion and Conclusion. The new stand design with the hydraulic loading device allows implementating of the dynamic testing methodology and guarantees high accuracy of evaluating the technical condition of the most widespread Russian and foreign volumetric hydraulic drives at repair and service centres. Further improvement of the evaluating the technical condition of volumetric hydraulic drives is related to the development of specialized software for processing and analysing test results in real-time.

Radiation evolution characteristics of the ejecta cloud produced by aluminum projectiles hypervelocity impacting aluminum plates

Series of hypervelocity impact tests of aluminum projectiles impacting aluminum plates were conducted using two-stage light gas gun, and the sequence spectrum and radiation evolution data under different impact conditions were obtained. The diameters of projectile ranged from 3 mm to 5 mm, the impact velocities varied from 3.13 km/s to 6.58 km/s, and the ambient pressures varied from 0.58 Pa to 990 Pa. In the use of the transient spectroscopy system, the two-sequence special spectra of the ejecta cloud in the band of 250 nm-310 nm were obtained, the colorimetric diagnosis method based on the special lines was developed, and the temperature and the particle number density of the impact products were obtained. Results show that the temperature of the impact products decreases with time in some tests, but increases with time in the other tests. The intensity evolution of special lines of the impact products were obtained by radiometer. It is found that when the ambient pressure is low enough and the impact velocity is high enough, three peaks exist in the radiation evolution curve. The requirements of the occurrence of the three peaks and the dependence of the three peaks on impact parameters were summarized.

Concurrent instabilities causing multiple rogue waves in infinite-dimensional dynamical systems

Complex instabilities are the major reason for drastic changes and extreme events in dynamical systems. Several modes of instability growing simultaneously with nonlinear interaction between them may lead to unforeseeable outcomes leading to catastrophic consequences. The most common examples of these instabilities are the modulation instability (MI). Studies show that an infinite number of instability modes remain active in a dynamical system. Although a one-mode MI can be analysed in the frame of a precise mathematical model, namely the Akhmediev breather, the dynamics of several concurrent MI modes referred to as the higher-order MI is very difficult to handle. We developed a unique geometrical approach that provides an entirely new and intuitive way to deal with higher-order MI. We apply this approach in description of higher-order modulation instability, multi-breather solutions, their degenerate versions and higher-order rogue waves of the nonlinear Schrodinger equation. For a system with infinitely many interacting instability modes, the band of the instability in this description is a hypercube, a multi-dimensional space of modulation frequencies. A large variety of special multi-breather and multi-rogue wave solutions of the nonlinear Schrodinger equation in this description corresponds to special points and lines within this hypercube.

The overabundance of the perfect and the restriction of evidentiality in Standard Azerbaijani: A diachronic study of -(y)Ib and -mIş

This article investigates the historical development and reorganization of variation in the individual cells of the Standard Azerbaijani perfect paradigms, a phenomenon known as overabundance (Thornton 2011, 2012). Unlike many previous examples of overabundance in the literature, the variation of the present perfect in Standard Azerbaijani applies to all the relevant verb lexemes in the language and shows no indication of developing verb classes. Rather, the present study argues that, (i) while there is an ongoing reorganization of this variation, it is along lines of specialization for paradigmatic oppositions in person marking, and (ii) this reorganization is attributable to analogical extension on the basis of structural asymmetries in the person-marking of the evidential paradigm. Differentiation by Person (Dmitriyev 1927, Əfəndiyeva 2005) is an inherent structural property of the Azerbaijani verb paradigm, manifested by analogical change. The synchronic asymmetries in the perfect paradigms are best explained as the result frequency-sensitive changes, i.e., lower frequency categories (but not lexemes) correlate with the persistence of variation.

Symmetries and equations of smooth quartic surfaces with many lines

We provide explicit equations of some smooth complex quartic surfaces with many lines, including all 10 quartics with more than 52 lines. We study the relation between linear automorphisms and some configurations of lines such as twin lines and special lines. We answer a question by Oguiso on a determinantal presentation of the Fermat quartic surface.

The Quasi-Normal Direction (QND) Method: An Efficient Method for Finding the Pareto Frontier in Multi-Objective Optimization Problems

In managerial and economic applications, there appear problems in which the goal is to simultaneously optimize several criteria functions (CFs). However, since the CFs are in conflict with each other in such cases, there is not a feasible point available at which all CFs could be optimized simultaneously. Thus, in such cases, a set of points, referred to as 'non-dominate' points (NDPs), will be encountered that are ineffective in relation to each other. In order to find such NDPs, many methods including the scalarization techniques have been proposed, each with their advantages and disadvantages. A comprehensive approach with scalarization perspective is the PS method of Pascoletti and Serafini. The PS method uses the two parameters of as the starting point and as the direction of motion to find the NDPs on the 'non-dominate' frontier (NDF). In bi-objective cases, the point is selected on a special line, and changing point on this line leads to finding all the NDPs. Generalization of this approach is very difficult to three- or more-criteria optimization problems because any closed pointed cone in a three- or more-dimensional space is not like a two-dimensional space of a polygonal cone. Moreover, even for multifaceted cones, the method cannot be generalized, and inevitably weaker constraints must be used in the assumptions of the method. In order to overcome such problems of the PS method, instead of a hyperplane (two-dimensional line), a hypersphere is applied in the current paper, and the parameter is changed over its boundary. The generalization of the new method for more than two criteria problems is simply carried out, and the examples, provided along with their comparisons with methods such as mNBI and NC, ensure the efficiency of the method. A case study in the realm of health care management (HCM) including two conflicting CFs with special constraints is also presented as an exemplar application of the proposed method.

Nuevas tendencias de la puesta en escena de las tragedias de William Shakespeare.

El artículo analiza el proceso de puesta en escena de las tragedias “Hamlet”, “Othello”, “Richard III” de W. Shakespeare en el teatro kazajo. Los autores pusieron especial énfasis en la demostración de la renovación espiritual de la sociedad y la realidad del período histórico del escenario del teatro nacional a través de las obras del gran dramaturgo. Es obvio que la dramaturgia de W. Shakespeare ha requerido una línea especial de pensamiento, enfoque cultural y lógica psicológica profunda por parte de los actores kazajos. Esta tendencia ha durado hasta hoy en día. Este documento justifica que es crucial para el teatro nacional kazajo considerar e investigar las preocupaciones comunes de la humanidad a través del gran dramaturgo inglés.