bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of two-stage growth during the formation of GaAs/Si heterostructures for the creation of optoelectronic devices
Authors: Geldash A A , Djuplin V N , Klimin V S , Solodovnik M S , Ageev O A
Published: December 2019

The development of GaAs/Si heterostructures can be an important stage for use as solar cells, LEDs and lasers based on silicon substrates. At present, A3B5 compounds grown epitaxial on Si substrates are of great interest because of the monolithic integration of optoelectronic devices with Si-based microelectronics. High-quality epitaxial growth of heterostructures will not only ensure high mobility of the carrier materials, but also preserve the advantages of lightweight and inexpensive Si substrates with high mechanical strength and excellent thermal parameters. However, obtaining A3B5 compounds with high quality crystals of GaAs/Si heterostructures is a difficult task due to the formation of an antiphase domain boundary as a result of the growth of polar GaAs on a non-polar Si substrate. Because of this, a high density of penetrating dislocations arises due to the mismatch of the lattice parameters (4.1%), as well as the coefficient of thermal expansion (62%).
Optically transparent conductive layer based on oriented metal networks
Authors: Nizameev I R , Nizameeva G R , Kadirov M K
Published: December 2019

The work is aimed at solving the problem of finding a promising alternative to indium tin oxide as an optically transparent electrode used in many modern devices such as solar cells, touch screens, transparent triboelectric generators, etc. In this paper, we propose the use of an original method for synthesizing oriented metal nano networks to create an electrically conductive layer on a surface of a glass substrate. Due to the orientation of metal networks, it is possible to significantly reduce the use of metal and increase open areas of the coating, which leads to preservation of electrical conductivity of the coating with a high degree of transparency. The method of depositing the proposed coating is based on the method of chemical precipitation from a liquid using a self-organized micellar template.
The model for in-plane and out-of-plane growth regimes of semiconductor nanowires
Authors: Berdnikov Y , Sibirev N V , Reznik R R , Redkov A V
Published: December 2019

In this work we present the model capable of prediction whether the vapor-liquid-solid growth would preferably result in the formation of in-plane (horizontal) or out-of-plane (vertical or inclined) nanowires. Within the model, we analyze the particular case of gold-catalyzed germanium nanowire growth on Ge(111), Ge(110) and Si(100) substrates. We focus on two aspects of the growth process: detachment of the catalyst from the substrate and stabilization of horizontal growth by nucleation at the nanowire-substrate-liquid line.
Dissociation and synthesis of target components during laser ablation of LiNbO3
Authors: Vakulov Z , Zamburg E G , Klimin V S , Miakonkikh A V , Clemente I E , Rudenko K V , Ageev O A
Published: December 2019

This paper shows the results of thermodynamic analysis of interfacial interaction in the lithium-niobium-oxygen system. The temperature dependences of the change in the Gibbs free energy calculated, taking into account the non-linear temperature dependences of the thermophysical properties of materials. Additionally, estimated the possibility of dissociation reactions of lithium and niobium oxides, as well as the reactions of lithium and niobium with oxygen. The results obtained can be used in the design and manufacture of integrated acousto-optic and piezoelectric devices, as well as for sensitive elements of sensors using various effects of surface acoustic waves.
A new method for monitoring the health condition based on nondestructive signals of laser radiation absorption and scattering
Authors: Davydov R V , Mazing M S , Yushkova V V , Davydov V V , Glinushkin A P , Stirmanov A V , Rud V Yu
Published: December 2019

The article describes a new method for processing a pulse wave, which is formed from the recorded absorption and scattering signals of laser radiation on a blood vessel or human tissues. A new method of tuning the optical part of the pulse oximeter has been developed to increase the reliability of the results in the rapid diagnosis of the human condition. Experimental data on studies of various people are presented.
Simulation of a THz radiation source on AlGaAs/GaAs superlattices
Authors: Dashkov A S , Goray L I
Published: December 2019

We report on the results of simulations of the carrier transport processes in THz radiation sources. The current-voltage characteristic, dipole matrix elements and LO-phonon relaxation time were obtained using the Ensemble Monte Carlo method, the shooting and effective mass methods. The electron-longitudinal phonon interaction assumed as a dominant mechanism of the carrier scattering for the current-voltage characteristic. The weakly coupled AlGaAs/GaAs superlattices considered for simulations.
Ultraviolet cathodoluminescence of pure zinc aluminate ZnAl2O4
Authors: Lisovskii S V , Meganov A V , Khrustov V R , Ivanov V V
Published: December 2019

The features of the intrinsic cathodoluminescence of pure zinc aluminate ZnAl2O4 having a radiation maximum in the range 250-270 nm are studied. The kinetics of the afterglow of a sample excited by short (∼ 2 ns) pulses is analyzed. Analysis and possible explanation of the influence of the type and composition of the atmosphere, in which zinc aluminate was annealed, is given. Possibilities for a multiple increase in the cathodoluminescence intensity of zinc aluminate for use in bactericidal lamps are demonstrated.
Nanosphere lithography on silicon oxide for high aspect ratio cryo etching of vertically-align silicon structures
Authors: Morozov I.A. , Gudovskikh A.S. , Kudryashov D. A.
Published: December 2019

Nowadays, classical silicon solar cell achieved efficiencies close to theoretical limit and new design of silicon solar cell is required. Vertically aligned silicon solar cells seems to be a promising design of future silicon multijunction solar cells. These structures can be produce with dry etching technics. However, dry etching requires high quality mask. Mask can be archived with classical photolithography, but photolithography is multistep process and cannot be used in mass production of solar cells, because of the price. Nanosphere lithography is a powerful one-step method to produce periodic mask on silicon, but polystyrene spheres does not have enough selectivity in silicon etching process. Etching depth in silicon that can be archived in cryo process with 900 nm polystyrene sphere is about 3 μm. For deep silicon etching, we have to use hard mask. In this paper, we investigated nanosphere lithography on 500 nm thick PECVD deposed silicon oxide on silicon. Influence of isopropyl content in nanosphere solution were investigated. The effect of process conditions is discussed in the paper.
Signal processing scheme for error control in visible light communication data transmission system
Authors: Borodkin A I , Gareev E Z , Krasavtsev I A , Kozyreva O A , Polukhin I S , Odnoblyudov M A , Bougrov V E
Published: December 2019

We developed wireless visible light simplex data transmission channel and error correction algorithm for the reciever. The system was design specially for using modern smartphone device as a receiver and a conventional domestic LED illuminator as transmitter. We calculated highest probable data transfer speed in our communication channel, fabricated the transmitter modulator and developed the client application for an android smartphone equipped with stock camera module, perform a series of data speed measurements and conducted the analysis of both analog and digital signals. The system allowed to transmit data with rates up to 8 kbps on distance up to 1.5 meters.
Temperature performance of InGaAs/InGaAlAsTemperature performance of InGaAs/InGaAlAs laser diodes with δ-doping active region
Authors: Rochas S S , Novikov I I , Gladyshev A G , Kolodeznyi E S , Maximov M V , Zubov F I , Shernyakov Yu M , Karachinsky L Ya , Zhukov A E , Denisov D V , Egorov A Yu
Published: December 2019

The optical gain performance of 1530-1565 nm laser diodes with active regions containing p-doped barrier layers has been investigated. We have studied the threshold current density and differential quantum efficiency in wide temperature range and compared modal gain behaviour of laser diodes made of heterostructure with delta-doped barrier layers by carbon at level of 1012 cm-2 and heterostructure with undoped barrier layers.
AlGaAs/GaAs solar cell with CNT transport layer: numerical simulation
Authors: Raudik S A , Mozharov A M , Mitin D M , Bolshakov A D , Fedorov V V , Neplokh V V , Rajanna P M , Nasibulin A G , Mukhin I S
Published: December 2019

AlGaAs/GaAs solar cells (SC) was modeled. Conventional SC was compared with structure with the thinner emitter. SC with additional CNT transport layer was simulated and compared with SC without it. The simulation was carried out with different geometry of the contacts and light flux. CNT transport layer has allowed achieving an increase in SCs efficiency up to 1.7% compared with metal contact grid.
Investigation of ITO magnetron deposition effect on carrier lifetime degradation in silicon wafer
Authors: Kudryashov D , Baranov A , Gudovskikh A
Published: December 2019

The effect of ITO magnetron deposition on carrier lifetime in silicon was demonstrated. The method of 2D photoluminescence decay time measurements revealed the lifetime degradation in silicon after magnetron deposition of thin ITO film which is used for top contact in modern solar cells.
Investigation of cryogenic dry etching of silicon on I-V curves of Schottky diodes
Authors: Maximova A , Gudovskikh A , Kudryashov D
Published: December 2019

I-V characteristics of silicon wafer with Schottky contacts were investigated to find out influence of dry plasma etching on defects emerging in the structure. Wafer was divided into two pieces, one of them has affected to cryogenic etching using SF6/O2 (in ratio 5:1) and a pressure 5 mTor for two minutes. The second part of the wafer was used as a reference. It was founded, that for the same contact diameters, etched samples demonstrate higher slope of the I-V curve at the direct voltage. A similar effect was observed in the case of the existence of a defective near-surface region, where carrier recombination is enhanced, which results a significant increase in the direct current.
Transverse mode switching in quantum well-dot lasers triggered by gain saturation
Authors: Payusov A S , Kharchenko A A , Serin A A , Kornyshov G O , Shernyakov Yu M , Mintairov S A , Kalyuzhnyy N A , Maximov M V , Zhukov A E , Gordeev N Yu
Published: December 2019

Having investigated narrow-ridge lasers based on a single layer of InGaAs quantum well-dots emitting at the wavelength of 1.06 μm we have shown anomalous transverse multimode lasing not observed in the broad-area lasers. The effect is shown to be caused by the wavelength shift triggered by the ground state gain saturation.
Multifocal Autofocused Airy Beam Metasurfaces
Authors: Mahdi Shanei M. , Hashemi Mahdieh , Naresh Kumar Reddy A. , Rodríguez Carlos. J. Zapata
Published: December 2019

To focus the incident light, both convex metalenses with hyperbolic phase profile and autofocused Airy (AFA) beams are widely used. To obtain AFA-based bifocal metalenses, we propose two methods in this article. One is to bring the two conjugate focal points of an AFA beam into the real space by applying a proper convex lens phase profile. The other is to use the inefficient central space between the two launched Airy beams with zero amplitude and constant phase profile as an independent metalens. We also show that combining the two introduced methods, leads the design to upgrade to a multifocal structure.
The interaction of an exciton and several optical modes in layer of GaAs
Authors: Belonovskii A V , Morozov K M , Fetisova M V
Published: December 2019

Theoretically, we calculated exciton fraction in polariton modes, which correlates with the intensity of the exciton radiation associated with these modes for several microcavities. Thus, we obtained the form of the dependence of the radiation probability on the eigenfrequencies of the structure.
Ultra high-speed all-optical coherent memory cell
Authors: Bagayev S N , Mekhov I B , Nikolaev V G , Chekhonin I A , Chekhonin M A
Published: December 2019

We study the interaction of two counterpropagating unipolar video pulses of electromagnetic radiation in a dense resonant two-level medium. The pulse durations are less than one oscillation period of an atomic transition. We show that a polariton cluster (i.e. the compact long-living strongly coupled state of electromagnetic field and matter polarization) is created, when two unipolar pulses collide in a resonant medium of the frequency ω0
(the pulses correspond to self-induced transparency solitons of the same amplitudes and opposite polarities).

We have studied for the first time the conditions of maximal excitation of a resonant polarization in the polariton cluster volume. We show that there exist optimal durations and amplitudes of the recording pulses. We studied the processes of double and multiple recording and erasing of an optical memory cell in a thin layer of a resonant medium (quantum dots). We demonstrated that the pulse rate of the recording-erasing pulses can reach 60 000 GHz and higher, which happens under the coherent regime of the interaction between the electromagnetic field and polarization of the medium.
Formation of catalytic centers for the growth of carbon nanostructures for nanophotonics devices
Authors: Klimin V S , Rezvan A A , Morozova J V
Published: December 2019

In this paper, we studied the effect of heating temperature on the geometric parameters of catalytic centers. The temperature range was from 600 to 900 °C with an interval of 50 °C, heating was carried out for 20 minutes. At the end of the experimental studies, the AFM and SEM images of the catalytic centers formed at various heating temperatures on the Ni/V/Si structure are presented. Based on the data obtained, the corresponding dependences of the packing density, height range and areas of catalytic centers on temperature were constructed. It was determined that the catalytic centers have the smallest volume of 0.5 nm3 and a diameter of 80 nm at a heating temperature in the range from 750 °C to 850 °C, which is caused by their uniformity and geometric shape.
Interpretation of photoluminescence spectra of metamorphic InAlAs/GaAs heterostructures
Authors: Denisova G A , Firsov D D , Komkov O S
Published: December 2019

The results of analyzing the photoluminescence spectra of metamorphic In0.75Al0.25As/In0.05-0.8Al0.95-0.2As/GaAs heterostructures grown by molecular-beam epitaxy method are presented. In the spectra of low-temperature photoluminescence, three emission peaks have been detected, which correspond to carrier recombination in different areas of the structure. These include a part of the In0.75Al0.25As “virtual substrate” grown at high temperature, and the area of a triangular potential well formed by the meta-morphic buffer layer and the “virtual substrate”. Photoluminescence related to defects in the high-temperature part of the “virtual substrate” was also measured.
CMOS compatible nanoantenna-nanodiamond integration
Authors: Komrakova S , Javadzade J , Vorobyov V , Bolshedvorskii S , Soshenko V , Akimov A , Kovalyuk V , Korneev A , Goltsman G
Published: December 2019

Here we demonstrate CMOS compatible method to deterministically produce nanoantenna with nanodiamonds systems on example of bull-eye antenna on top of on hyperbolic metamaterials. We study the statistics of the placement of nanodiamonds and measure the fluorescence lifetime and the second-order correlation function of NV-centers inside nanodiamonds.
Magneto-optical properties of easy-plane and easy-axis garnet ferrite films for eddy current testing
Authors: Lugovskoy N.V. , Berzhansky V.N. , Semuk E.Yu. , Lyashko S.D. , Shaposhnikov A.N. , Evtukhova E.A. , Mikhailova T.V.
Published: December 2019

The paper presents the magnetic, optical and magneto-optical properties of easy-plane and easy-axis films on the base of Bi-garnet. The possibilities and features of the operation of these films as sensors in eddy current magneto-optical introscopy are shown on the example of visualization of linear defects in products made from aluminum alloys.
Simulation of induction heating of a titanium sample in a container with a carbon-containing medium and determination of the amount of heat losses during chemical heat treatment
Authors: Voyko A , Fomina M
Published: December 2019

In this work, the process of induction heating of a container with a titanium sample in a carbon-containing medium was simulated using the finite element method. The dependence of the inductor current I and the duration of treatment on the heating kinetics T(I,t) of the “inductor – container – sample” system taking into account the heat losses QL(I, T) on the process of chemical-thermal treatment of titanium was established.
Ti/4H-SiC Schottky diode with breakdown voltage up to 3 kV
Authors: Knyaginin D A , Rybalka S B , Drakin A Yu , Demidov A A
Published: December 2019

In this study the breakdown voltage for Ti/4H-SiC type Schottky diode with six guard rings and JTE layer has been calculated by mean of numerical simulations. It is established that increase of the n-type 4H-SiC epitaxial layer from 14 up to 20 μm and addition of JTE layer lead to increase of breakdown voltage value on ∼900 V in contrast to the same diode without JTE. The above-mentioned diode’s structure gives the possibility for designing and production of diode with higher breakdown voltage value up to 3 kV.
Electronic transport properties of microcrystalline GaP
Authors: Uvarov A V , Gudovskikh A S , Vasilev A A
Published: December 2019

Electronic properties of microcrystalline gallium phosphide films deposited on fused silica substrates by plasma-enhanced atomic layer deposition at the temperature of 380°C were investigated. The values of the activation energy of conductivity (Ea = 0.247 eV), the optical value of the band gap (Eg = 2.2 eV) and the long-wavelength edge of photoconductivity (Eph = 1.8 eV) were obtained for this material. The value of Ea could associated with position of Fermi level near to the bottom of the conduction band or barriers at the grain boundaries. The long-wavelength edge of photoconductivity in the layer of microcrystalline GaP is a consequence of the presence of interband states, which are associated with partially disordering.
Formation of out-of-plane film micro arch by methods of technological control of internal stress
Authors: Enns Y. , Kleimanov R.
Published: December 2019

In this work is presented the analysis of the manufacturing technology of arcuate elastic elements. In the course of the work, the technological problems of the formation of out-of-plane microelectromechanical structures with the use of surface micromachining were studied. Internal stresses were controlled by varying the pressure of the working gas during sputtering. The use of this method allowed forming the arcuate profile of the Cr-Cu-Cr film structure.
Analysis of doping distribution in horizontal GaAs nanowires with axial p-n junction by the conductive atomic force microscopy
Authors: Borodin B R , Alekseev P A , Dunaevskiy M S , Khayrudinov V , Lipsanen H
Published: December 2019

This work presents the results of an investigation of in plane horizontal GaAs nanowires by Scanning Probe Microscopy (SPM) methods. Topography and a local conductivity map of the horizontal nanowire with axial p-n junction are obtained. The distribution of doping and position of p-n junctions in nanowires are visualized. The I-V curves of differently doped parts of nanowires were measured. These data can be important for the understanding of the doping incorporation mechanism of GaAs nanowires.
Testing of Image Resolution Enhancement Techniques Using Bi-cubic Spatial Domain Interpolation
Authors: Bustomi M A
Published: December 2019

The technique for increasing digital image resolution from low-resolution image to high-resolution image based on digital image processing is called the super-resolution technique. In this paper, a super-resolution technique is presented using a two-dimensional bi-cubic interpolation method in the spatial domain. The order of the super resolution method applied is as follows: (1) selecting ten images as samples, (2) decrease the sample image resolution to one-fourth of the original resolution by deleting three quarters of the pixel number, (3) increasing the image resolution of a quarter of the part becomes like the initial resolution using bi-cubic interpolation for three quarters of the additional new pixels, (4) testing this bi-cubic interpolated image with the same pixel-sized initial image, (5) using parameters: average value, minimum value, maximum value and standard deviation value as a comparison parameter between bi-cubic interpolated images and the same pixel-sized initial image. The results obtained from the super-resolution technique using spatial bi-cubic interpolation are: (1) The average error value of the bi-cubic interpolation method in image objects in this study is between 4% to 10% or still quite low, (2) Bi-cubic interpolation methods can work well on square pixel-sized images (m = n) compared to non-square pixel-sized images, (3) Bi-cubic interpolation turns out to produce an array of image pixel values that mirror symmetry against the main diagonal lines of the image before being interpolated.
The recent advances on potential solid electrolytes for all-solid-state supercapacitors: A short review
Authors: Ainiya Lisda
Published: December 2019

The increasing demand to develop renewable energy has increased drastically due to limited resources and environmental problems of fossil fuel. The most widely used energy storage devices are batteries and capacitors. Supercapacitors, on the other hand, can induced higher power density by fast charging/discharging rate which results in higher power density and longer cycle life compared to batteries and fuel cells. To fulfil the demand for safer energy sources, the use of highly flammable organic liquid electrolytes and polymer separators must be replaced by solid electrolytes. Therefore, supercapacitors with solid electrolytes can be alternative renewable energy. Commercially, there are three types of electrolytes of supercapacitors: aqueous electrolytes, organic electrolytes, and ionic liquids. In this paper, there is selective review on solid electrolytes of supercapacitors including chitosan, polyacrylamide, poly(aryl ether ketone), and polyethylene glycol. Overall, this paper aims to provide comprehensive reviews on recent advances in potential solid electrolytes of supercapacitors and the remaining challenges.
Mercury and Cyanide Pollution on the Aquatic Organism in Sekotong People Gold Mining
Authors: Suhadi  , Sueb  , Syamsussabri M
Published: December 2019

This study aimed to determine the pollution of mercury and cyanide in gold mining conducted by Sekotong people. Samples of this research were water and the aquatic organism around in people gold mining consisting ofAcetes indicus, Perna viridis, Polymesoda expansa, Plotosus canius, Scylla serrata, Tegillarca granosa, Moolgarda seheli,andCrassostrea gigas.The content of mercury in the samples can be known using Atomic Absorption Spectrophotometry (ASS). In the same way, in order to know the content of cyanide in the samples can be obtained using Ultraviolet-Visible (UV-Vis) Spectrophotometry. The results showed that Sekotong people’s gold mining has been contaminated with mercury and cyanide in aquatic and animal environments exceeding the specified threshold value with the highest level of mercury 48.91 ppm and cyanide 90.22 ppm.
The effectiveness of nutrient variation to hydroponic Caisim (Brassica juncea L.) growth
Authors: Dewi S K , Rahayu Y S , Bashri dan A
Published: December 2019

One type of vegetable that is popular among the Indonesian is mustard greens(Brassica junceaL.), which is also known asCaisimbecause it is often processed into various dishes and contains various ingredients and vitamins which are good for health. The last few yearsCaisimproduction has decreased, one of the causes is the constraints in the cultivation process, especially in the use of fertilizers due to the relatively long-term use of inorganic fertilizers. To improve the cultivation ofCaisimwithout looking at the soil conditions, we can use a hydroponic system. However, hydroponics need more cost because the AB MIX nutrition is still relatively expensive, so it needs an alternative nutrient as a substitute for AB MIX which has the same ability. AB Mix is a mixture of fertilizer A and fertilizer B. Fertilizer A contains potassium while fertilizer B contains sulfate and phosphate. An alternative nutrient as a substitute for AB MIX which has the same ability, such as liquid fertilizer based on local microorganisms (LMO) which has properties that are easily absorbed by plants so that the use of organic nutrients can be used as a source of substitute nutrition, which is more economically affordable and has a very good influence onCaisimand is expected to increase production inCaisimcultivation. This study used a Completely Randomized Design with a single factor experimental design consisting of 4 treatments, namely a combination of AB MIX solution and various kinds of LMO-based organic nutrients as follows: A = LMO A 5 ml + AB MIX 5 mL/L of water; B = LMO B 5 mL + AB MIX 5 mL/L water; C = LMO A 5 mL + MOL B 5 mL/Liter water; D = AB MIX 10 mL/L water. The variables observed were plant height, number of leaves, and biomass ofCaisim.The results showed that the variation of AB MIX nutrition and liquid organic fertilizer based on LMO effectively increased the growth ofCaisimplants. The highest average plant height was given byCaisimwith AB MIX nutrition, which is 69.2 cm. The highest average number of leaves was obtained byCaisimwhich was grown with a combination of LMO A and LMO B nutrients, which was 27.8. The largest average wet weight was given byCaisimwith AB MIX nutrition, which is 32.3 g. According to the three parameters, the use of ab mix nutrients is 10 mL / L water and a combination of LMO A 5 mL + LMO B 5 mL / L water is the most effective combination of nutrients for hydroponicCaisimgrowth.
Mathematical Representation of Middle School Students in Solving Fractional Problems Based on Sex Difference
Authors: Fadhilah N , Budiarto M T , Rahaju E B
Published: December 2019

Mathematics is one of the subjects taught in schools from elementary education to higher education, in which mathematics cannot be separated from the problem-solving activities. This is because the problem-solving activities is one of the most important skills taught to students early, as a preparation to face problems in the future. Fraction is one material that has a relatively difficult and challenging concept for students. This study aims to describe the students’ representation of middle school in solving fractional problems based on sex difference used Polya rules. This research is an exploratory research with a qualitative approach that produces descriptive data. This research was conducted on 7th grade students of SMP Negeri 53 Surabaya. Written data was taken from the results of the written test which produced two research subjects. They are one male student and one female student who have a similar mathematical ability. Data collection method used are the test method by giving the task of mathematics and method of interview. The results of the research showed that the mathematical representation of male junior high school students in solving fractions is by presenting the data provided using symbol manipulation and given verbal information with written words or sentences. While the mathematical representation of female junior high school students in solving fraction questions uses more verbal forms or written sentences as explanatory illustrations. So the representation ability of students can be used as a reference to determine the extent to which a student understands a problem at hand.
Students’ Strategies to Solve Reversible Problems of Function: The Part of Reversible Thinking
Authors: Maf’ulah S , Juniati D
Published: December 2019

This study aimed to reveal students’ strategies to solve reversible problems, particularly to function course. Individuals’ competence to solve reversible problems is the part of reversible thinking. This way of thinking refers to a reversible two-way relationship. Providing reversible problems is a way for teachers to develop their students’ reversible thinking. It was qualitative. 105 students who were prospective teachers of mathematics were selected as the subject of this study, and it took a test containing some reversible problems, such as function along with its graphic and between derivative and integral, as the instrument. The students’ results were further analyzed to reveal their strategies of solving those reversible problems. The finding showed that among 105 students, 62% of them were capable to draw the graph of an identified function through 4 different strategies, while 28% of them were capable to define the function of an identified graphic through 5 different strategies. The significant difference between those two percentages implied that only few students were capable to both drawing the graphic of an identified function and defining the function of an identified graphic. Overall, it indicated that the students were still less in constructing a reversible relationship between function and its graphic.
Student’s Geometric Thinking in Understanding Volume with Three-Dimensional Images of Cubes and Nets
Authors: Setiawati H , Juniati D , Khabibah S
Published: December 2019

This study aimed at describing the thinking skills of junior high school students in solving problems about the volume of cube and cuboid presented in the form of images of nets and solid figure geometry. This research was a descriptive study with a qualitative approach. This research was conducted at eighth grade class in Islamic Junior High School (MTs) Nurul Huda, Sidoarjo, Indonesia. The research subjects were two students, male and female in the same class of seven classes. The instruments used in this study were geometry test and interview. Geometry test was designed to determine student’s thinking in understanding volume with three-dimensional images of cubes and nets. Interview was used to make the researcher easier to explore how the students completed the given geometry test on the problem of the volume of cube and cuboid. Student’s thinking ability was explained based on three abilities according to Sternberg. The results showed that the female student had analytic and creative abilities in understanding images for the volume of cube and cuboid, but the male student tended to be more thoughtful towards abstract concepts. For practical ability, the male student had practical ability better than the female student.
Proving the Pythagorean Theorem to Junior High School students through the Asian method
Authors: Wijayanti P , Hidayanti A N
Published: December 2019

The development of right triangle concept has been known since ancient Egypt and is still be used in daily life until now. One of the most popular theorems that relate to the right triangle is Pythagorean Theorem. In its development, the Pythagorean Theorem has been proven by mathematicians with different methods. Based on historical developments there are approximately 200 proofs of the Pythagorean Theorem that has been found. Nevertheless, history still has interesting mysteries to study especially for the development of the Pythagorean Theorem in Asia. In student textbooks, the proof of Pythagorean Theorem introduction often comes from the European continent such as proof by Pythagoras, Euclid, and Leonardo Da Vinci. This caused Pythagorean Theorem’ development in Asia as if it were excluded, the proof of Pythagorean Theorem in Asia also developed by mathematicians such as Bhaskara and Zhao Shang with different names. Even so, the discussion of those Pythagorean Theorem proof can be introduced to students as an initial concept in Pythagorean Theorem chapter and presented pleasantly in the form of mathematics historical comic to make it more attractive. The discussion result in this journal is also in line with the 2013 curriculum which emphasizes student activity and fun learning model.
Mathematical Problem Proving and Problem Posing
Authors: Siswono T Y E , Hartono S , Kohar A W
Published: December 2019

This article describes students’ tasks that concerned to assess students’ problem proving and problem posing on triangle tasks. This descriptive-explorative research involves 24 prospective mathematics teachers at a state university in Surabaya, Indonesia. They had to answer three questions. The first question related to problem proving of triangle theorem. The second question related to their perception of the first question, and the last question related to the problem-posing task. A Newman analysis is used to analyse the data. The analysis of the data focused on students’ problem proving and students’ problem posing of triangle task. The results showed that most of them were correct to answer the question as many as 41%. It can be seen of the first question was performed by the highest number of them. However, some of them still have a perception of the first question is a problem, because it shows as many as 95% of 24 students choose it. They also have some weaknesses in proving problems, mainly misinformation or ambiguity about the problem, it is not a category as a problem proving. They constructed proof by formal proof with a low level of problem difficulty as many as only 38 % of them.
An Effort in Teaching Invertebrates and Training Digital Literacy to the Students
Authors: Putri I D T , Ambarwati R
Published: December 2019

Digital literacy is an ability to understand and use information in multiple formats and sources while presented through computers. The research purposes have analysed the influence of the electronic Invertebrate book on students’ digital literacy and learning outcomes, as well as describe student responses upon learning process using electronic Invertebrate book. This research used mixed-method. The research samples selected using purposive sampling. Student’s digital literacy and learning outcomes, in the form of pre-test and post-test, were analysed quantitively using normalised gain scores (g). The difference between pre-test and post-test in treatment or control class calculated using Wilcoxon test. Meanwhile, the post-test score and normalised gain score between treatment and control class calculated using Mann-Whitney test. The student’s responses through the learning process were analysed descriptive-quantitatively using questionnaire. The result revealed that about 57% of students completed the digital literacy test and 100% of them enhanced in the category of medium to high on digital literacy skills.
The Effect of Environmental Pollution Module on Environmental Worldview in Senior High School
Authors: Syamsussabri M , Suhadi  , Sueb
Published: December 2019

This study aimed to know the effect of environmental pollution module on the environmental worldview in senior high school. This type of research is quasi-experiment. The research instrument was a scale of the New Ecological Paradigm (NEP). This research conducted at SMAN 1 Lembar. The research subjects were 54 students of class XI Mathematics and Natural Science. Samples were taken by cluster sampling with the equality test. The analysis of data used One-way Analysis of Covariance (ANCOVA). The results showed there was the effect of the environmental pollution module on the environmental worldview in senior high school with p-value < .005.
Learning Management System with Moodle to Enhance Creativity of Candidate Physics Teacher
Authors: Gunawan G , Sahidu H , Susilawati S , Harjono A , Herayanti L
Published: December 2019

Creativity is one of the main goals of education. Debriefing creativity is essential to win in global competition. Practicing creativity can be done by utilizing the development of information and communication technology, including learning physics for candidate teachers. One innovation that can be done to improve the quality of creativity-oriented learning is to develop a learning management system (LMS) with Moodle. The aim of this research is to produce a learning management system with Moodle that can enhance the creativity of candidate physics teachers. However, the focus of this article is to explain the results of trials of the effectiveness of products that have been developed to increase the creativity of candidate physics teachers. This research is a research development that adopts ADDIE research design (analysis, design, develop, implementation, and evaluate). The research instrument used to measure candidate physics teacher creativity is a creativity test consisting of 80 questions and consists of various types of tests both multiple-choice, short answers, and essays, which have been developed according to creativity indicators. To find out the increase in student creativity, data were analysed using the n-gain test. The results of the study show that the model develops successfully trained the creativity of candidate teachers, including verbal, figural, numerical, and procedural aspects. This model allows lecturers to manage learning and exchange information with students quickly and flexibly.
Practicality and effectiveness of SETS based learning materials to trained students’ higher-order thinking skills
Authors: Hasanah A F , Raharjo  , Rachmadiarti F
Published: December 2019

At present, there are no many environment-based learning activities with interesting practices that utilize technology and at the same time to train students with higher-order thinking skills. Therefore, a learning instrument is needed to implements these practices. This research aims to describe the practicality and effectiveness of SETS based learning materials for higher-level thinking skills of 1st grader of junior high school in Sciences subject, including (1) describing the implementation of learning, (2) describing student responses toward learning, and (3) describing higher-order thinking skills of students. Research methods used were observation method for learning realization, questionnaire method for student responses, and test method to determine learning achievement (pre-test and post-test). Research instruments used were observation sheets of learning realization, questionnaire sheet for student response, and sheets of the higher-order thinking skills test. Results of the research showed that (1) learning based on the SETS approach was conducted very well; (2) student responses toward learning are highly positive; and (3) higher-order thinking skills of students have increased after SETS-based learning materials have been applied. This is shows that SETS learning materials are stated to be practical and effective to be used in learning to trained higher-order thinking skills.
The Effectiveness of Guided Inquiry Learning Model to Improve Science Process Skill on Heat Matter
Authors: Yunianti A U , Wasis  , Nur M
Published: December 2019

This research aimed to describe the effectiveness of guided inquiry learning model to trained science process skill. Research conducted in SMA Kemala Bhayangkari 1 Surabaya at grade XI on heat matter by using one group pre-test and post-test design. Data collecting techniques consist of tests and questionnaires. The effectiveness of the guided inquiry model is obtained based on the science process skill test, learning achievement of knowledge test and student responses. Science process skill test and learning achievement of knowledge test obtained based on the results of the pre-test and post-test. Student responses are obtained based on the results of the questionnaire that includes the student responses to learning. The data analysis using n-gain score to determine the improvement of science process skill and learning achievement of knowledge while descriptive quantitative to describe student’s response. Result of this research shows that (1) indicators of science process skill improved with high category (2) learning achievement of knowledge improved with middle category (3) student responses to learning are highly positive. Based on those results indicates that guided inquiry model is effective to improve science process skill on heat matter.
Pre-service Physics Teachers Perception about Concept Map, Mind map, and Link Map for Innovative Learning
Authors: Lestari Nurita Apridiana , Jatmiko Budi , Dwikoranto  , Prahani Binar Kurnia , Deta Utama Alan , Bachtiar Rayendra Wahyu
Published: December 2019

This study aims to describe students’ perceptions of the characteristics of assisted learning mapping methods such as concept maps (CM), mind maps (MM), and link maps (LM). The study was conducted with qualitative and quantitative data collection with a sample of 10 students as pre-service physics teachers. Quantitative data becomes a supporting part of the qualitative description. Each student was asked to make a concept map, mind map, and link maps with physics material. Furthermore, students’ performance is analyzed in the description form of the differences and effectiveness of the mapping when applied in physics learning. These results indicated that mapping has a positive effect on the development of students’ thinking abilities, especially in identifying the right concepts for physics material.
Research on gamma spectrum semi-quantitative analysis based on convolutional neural network
Authors: Li Fei , Wang Jing , Ge Liangquan , Hu Fangyan , Cheng Feng , Sun Kun
Published: December 2019

In the field of practical application of nuclear technology, one of the vital steps is the interpretation of gamma energy spectrum, which can obtain the type and content of radionuclides and achieve further analyzation. Convolutional neural network is one the most basic and effective algorithm structures in deep learning because it has local receptive field, weight sharing and down sampling structure, it solves the problem of parameter expansion caused by full connection and reduces the number of weights. That can be used to study the resolution of gamma-ray spectra of convolutional neural networks. This paper introduces the spectral forming principle of gamma spectra and the convolutional neural network, and USES the convolutional neural network to study the spectral decomposition of gamma spectra. In this paper, a multi-layer convolution neural network model is built based on C# software. The convolution neural network is applied to gamma-ray spectrum decomposition, and the U, Th, K nuclides are identified and semi-quantitatively calculated. By identifying and analysing different energy spectrum data, it is shown that the modified model structure can be applied to the spectral decomposition of gamma spectrum.
Study on identification and classification of hidden dangers in highway toll stations based on accident causation theory
Authors: Jing Qiangqiang , Bi Yufeng , Liu Niantao , Zhang Qiangmin , Chen Renshan
Published: December 2019

Aiming at high safety risk of expressway toll station, based on the theoretical model of accident cause, this paper makes a systematic analysis and correlation test on the unsafe state of object, personal unsafe behaviour, and the imperfection of safety management system within the jurisdiction of expressway toll stations. Through statistical analysis, the types and distribution areas of unsafe physical state, the types and main causes of unsafe behaviours within the jurisdiction of toll stations are identified. The results show that: education and training, risk management and control, hidden dangers, operating procedures, equipments and facilities management, emergency management, etc., have a great impact on the physical safety of highway toll stations; bad driving habits, trouble free mentality, poor safety awareness, lack of safety knowledge are the main reasons for unsafe behaviours. The results of the study have guiding significance for the risk management of toll station.
The application and evaluation of “Production-oriented Approach” in College English Teaching
Authors: Zeng Ruiyun , Li Qianmei
Published: December 2019

This paper introduces a semester-long of experiment process with the production-oriented approach (POA) to test the effectiveness of POA in an ordinary university in China. The findings are as follows. First, POA has obvious effects on improving the overall English level of students. Second, with POA, there is an obvious increase in students’ reading ability, a slight increase in their listening ability, and a slight decrease in their vocabulary ability. This paper analyzes the research results and puts forward corresponding solutions to the problems existing in the implementation process of POA in ordinary colleges and universities.
Decomposition and reconstruction of ore-caused anomalies information by airborne gamma-ray spectrum based on fractal singular value decomposition method
Authors: Sun Kun , Ge Liangquan , Li Fei , Zhang Qingxian , Gu Yi , Lai Wanchang
Published: December 2019

Identification method research on ore-caused anomalies information is one of the core technologies of airborne gamma-ray spectrum data post-processing. This paper proposed a decomposition and reconstruction method of anomaly information called fractal singular value decomposition (FSVD), aiming at the current ubiquitous truncation error and boundary effect problems in filter design in ore-caused anomaly information identification methods in airborne gamma-ray spectrum. Based on the multi-fractal theory, this method decomposes the singular value of the specific nucleus activity data of the airborne gamma-ray spectrum under time series, and quantitatively calculates the fractal singular value truncation parameter according to residual square sum minimum principle. According to the calculation result, the original data is partially reconstructed to rebuild the ore-caused anomalies information. This paper used the 1:50000 airborne gamma-ray spectrum trial production flight data of a certain area in Inner Mongolia (the surveying area contains proved metal ore occurrences) to verify the method. The results show that: after the original signals are decomposed by FSVD, the high, medium and low singular values can represent the background, anomaly, and noise signal, respectively. At the same time, the false anomaly signals caused by flight error exist in high singular values. After reconstructing the decomposed signals according to median singular values, background noises can be effectively separated, the ore-caused anomaly in the known ore-caused anomalies can be identified and band-like false anomalies caused by time domain batches can be removed.
Research on knowledge mapping construction of big data
Authors: Jiang Xiulian , Ju Peng , Song Yining , Mao Lingcheng , Xie Guifang
Published: December 2019

The diversified development of network applications and the informatization of social life are triggering explosive growth of data. The core journal articles based on big data research in the 2011-2018 database, which are included in the CNKI database, are used as research objects, and CiteSpace, Netdraw, and Ucinet are used as tools for visualizing knowledge maps. Visualize the growth trend of big data literature, authors and institutional cooperation networks; use co-occurrence analysis and cluster analysis to mine research hotspots of big data; use mutation word detection and time zone view to study evolution path of big data development. The research hotspots of big data are shown in three directions of big data technology, application field and challenges brought by big data. The evolution path of the field of big data shows that in early stage, technology research related to big data was mainly conducted, and later, it developed into the research trend of technology and application.