bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral analysis of the electroluminescence and photoresponse of heterostructures with InGaAs quantum objects
Authors: Salii R A , Evstropov V V , Mintairov S A , Mintairov M A , Shvarts M Z , Kalyuzhnyy N A
Published: December 2019

In this work, physical and optical properties of In0.8Ga0.2As quantum dots (QDs) embedded in the structure of a single-junction GaAs solar cell (SC) grown by MOVPE technique were investigated using spectral characteristics of external quantum yield (EQE) and electroluminescence (EL). It has been found that, in characterizing QD physical parameters, simplified model of a thin stressed quantum well can be applied to a wetting layer (WL). It has been demonstrated that the EL spectra allows determining the absorption energy of photons in WL and QDs more accurately compared to the EQE spectra. Energies of “Ee-Ehh” and “Ee-Elh” transitions in WL have been determined and were 1.325 eV and 1.388 eV respectively. The calculated values of the WL thickness (5.63 Å) and In composition of QDs (xIn = 80%) coincide with the technological parameters used in the epitaxial growth of the device.
Φ-OTDR based on tunable Yb-Er:phosphate-glass laser
Authors: Choban T V , Zhirnov A A , Chernutsky A O , Stepanov K V , Pniov A B , Galzerano G , Karasik V E , Svelto C
Published: December 2019

In recent times, phase-sensitive optical time domain reflectometers became widely common for monitoring of extended objects and providing necessary measurements in optical telecommunications. In this paper we present our investigations and results in the development and characterization of a new type of laser for phase-sensitive optical time domain reflectometry.
Stabilizing effect of injection in broad-area lasers
Authors: Yarunova E A , Krents A A , Molevich N E , Anchikov D. A.
Published: December 2019

In this paper, spatiotemporal dynamics of broad-area lasers with external optical injection is investigated. We demonstrate theoretically that relatively small optical injection suppresses unstable transverse modes and stabilizes laser output. In this paper, the general case of a mismatch in the frequency of the radiation injected and generated by a laser was numerically investigated. It is shown that the frequency mismatch does not destroy the stabilizing effect.
Polarization properties of single-walled carbon nanotube thin film on silicon substrate in terahertz frequency range
Authors: Kvitsinskiy A , Demchenko P , Litvinov E , Masyukov M , Anoshkin I , Vozianova A , Khodzitsky M
Published: December 2019

Terahertz time-domain spectroscopic polarimetry (THz-TDSP) method was used to study of polarization properties of a randomly oriented single-walled carbon nanotube (SWCNT) thin film on a silicon (Si) substrate in terahertz (THz) frequency range under an external optical pumping (OP) and an external static magnetic field (MF). Frequency dependencies of azimuth and ellipticity angles of a polarization ellipse and the polarization ellipse at various frequencies of the Si substrate and the SWCNT thin film on the Si substrate were obtained experimentally. The results confirm the fact that, based on carbon nanotubes, it is possible to devise efficient tunable THz polarization modulators for use in the latest security and telecommunication systems.
Study of the effect of carbon nanotube lengths on their conductivity in the terahertz frequency range during optical pumping
Authors: Baimagambetova R , Gomon D , Demchenko P , Anoshkin I , Khodzitsky M
Published: December 2019

In this work, the conductivity of carbon nanotubes with the different lengths with / without optical pumping in the frequency range of 0.2 - 1 THz was experimentally studied. The results show that the restructuring of the geometric properties of carbon nanotubes will allow to create THz devices with tunable spectral characteristics.
Numerical simulation of a nitride single quantum well laser
Authors: Medvedeva E E , Konoplev S S , Savelyev A V
Published: December 2019

Numerical simulation of a quantum well on nitrides, optical interband transitions in low dimensional semiconductor structures (semiconductor quantum wells), conduction-heavy hole and transitions in quantum wells, refinement of the gain for a quantum well on nitride materials with allowance for the overlap integral and approximate this.
Large active area superconducting single photon detector
Authors: Moshkova M , Morozov P , Divochiy A , Vakhtomin Yu , Smirnov K
Published: December 2019

We present development of large active area superconducting single-photon detectors well coupled with standard 50 μm-core multi-mode fiber. The sensitive area of the SSPD is patterned using the photon-number-resolving design and occupies an area of 40×40 μm2. Using this approach, we have obtained excellent specifications: system detection efficiency of 47% measured using a 900 nm laser and low dark count rate of 100 cps. The main advantages of the approach presented are a very short dead time of the detector of 22 ns and FWHM jitter value of about 130 ps.
Gold nanoantennas for enhancement of photon emission from STM contact
Authors: Shkoldin V A , Permyakov D V , Golubok A O , Uskov A V , Samusev A K , Mukhin I S
Published: December 2019

Inelastic electron tunneling in a tunnel junction may be used as an electrical nanosource of surface plasmon polaritons and photons. In this work, we investigate emission from tunnel contact between the Platinum/Iridium tip and a thin Au film on glass. The experiment has shown that the intensity of this emission can be enhancement by use a gold nanoantenna located in the vicinity of tunnel contact.
Second harmonic generation and charge relaxation of poled glasses
Authors: Reshetov I V , Kaasik V P , Lipovskii A A , Tagantsev D K
Published: December 2019

We measured thermal relaxation of the second order nonlinearity (SON) observed in a thermally-poled soda-lime silicate glass. It is shown that 50-min annealing of the glass at 400°C results in a complete SON degradation. Performed studies of thermo-stimulated depolarization current (TSDC) revealed that the poling-induced spatial electric charge relaxes above the glass transition temperature. This indicates that SON is not induced by this spatial charge.
Investigation of optical properties of In(Ga)As/GaAs mesa structures with active region based on quantum wells, quantum dots, and quantum well-dots
Authors: Dragunova A S , Kryzhanovskaya N V , Maximov M V , Mintairov S A , Kalyuzhnyy N A , Moiseev E I , Mukhin I S , Tikhomirov V G , Zhukov A E
Published: December 2019

In this work photoluminescence (PL) of mesa-structures that contain three different types of active regions based on InGaAs/GaAs quantum wells (QWs), InAs/InGaAs/GaAs quantum dots (QDs) and InGaAs/GaAs quantum well-dots(QWD) is studied. Comparative analysis of the PL intensity obtained at different temperatures and optical excitation powers on mesa diameter is done.
The influence of iron concentration on the cathodoluminescence kinetics in the mid-IR range in ZnSe:Fe crystals
Authors: Chukichev M , Rezvanov R , Chegnov V , Chegnova O , Mironov S , Gladilin A , Il’ichev N , Kalinushkin V
Published: December 2019

Integral intensity and kinetics dependences of cathodoluminescence of ZnSe:Fe crystals in mid-IR spectral range was studied. Concentration of iron varied from 0.01 to 14 wt.%. The experiments were carried out in 77 - 300 K temperature range. It is established that the luminescence pulse rise time is longer than excitation pulse at low iron concentration at 77 K temperature. The increasing ones lead to shortening of the luminescence pulse rise time, decreasing of the luminescence lifetime and increasing of the luminescence intensity in mid-IR. The annealed ZnSe:Fe concentration series in vapour Zn are reproduced the same trends. The nature of observed experimental effects is discussed.
SERS induced by Au/ZnO plasmonic nanorods coupled to Au nanoparticles
Authors: Kaydashev V. , Zolotukhin P. , Belanova A. , Anokhin A. S. , Minasyan T. , Chernishev A. , Kaidashev E. M.
Published: December 2019

We study the surface enhanced Raman scattering of Methylene Blue (MB) dye molecules induced by 3D array of “hot spots” made of vertical Au/ZnO core-shell nanorods coupled to self-assembled plasmonic Au nanoparticles. SERS substrates based on array of nanorods coupled to nanoparticles show much better performance compared with bare Au/ZnO nanorods. The hybrid 3D SERS substrate perfectly resolve Raman spectra of MB molecules chemisorbed from solutions with analyte concentrations of ∼10-7 M even upon washing of a sample i.e. when only chemisorbed molecules were remained. Raman signal enhancement results from the superposition of two effects, namely, the ability of a plasmonic coupled system to enhance the Raman scattering via local field enhancement and from the large 3D surface which provides more adsorption sites compared with traditional 2D surfaces.
Numerical Analysis Spectral Huygens Filter for pulsed broadband Terahertz Radiation
Authors: Liu X , Petrov N V , Kulya M S , Tsypkin A N , Grachev Ya V , Kozlov S A
Published: December 2019

In this paper, we consider a Huygens filter for a specified frequency lying within a broad spectrum of a pulsed THz radiation which represents simplest two-zone plate. The condition of the infinite plane wave and the Gaussian beam are separately used as the initial source has been discussed. A property method of terahertz spectral filter has been explored.
The influence of optical density change on measurement error of refractive index in flowing liquid
Authors: Grebenikova N M , Davydov V V , Rud’ V Yu
Published: December 2019

The article discusses the physical processes in a flowing fluid that affect the change in its optical density. Changes in the refractive index and its errors in single-component and multicomponent media for different fluid flow regimes are investigated. A new model has been developed for calculating error of refractive index, considering the non-uniformity of optical density in a stream liquid. A technique is proposed for selecting a refractometer model for reliable monitoring the state of liquid environment.
Mobility of a two-dimensional electron gas in the AlGaN/GaN heterostructure: simulation and analysis
Authors: Volcheck V , Stempitsky V
Published: December 2019

At temperatures higher than the room temperature, a two-dimensional electron gas (2DEG) formed at the AlGaN/GaN heterointerface can be characterized by the three dominant scattering mechanisms: acoustic deformation potential, polar acoustic phonon and polar optical phonon scatterings. An analytical model describing the 2DEG mobility limited by these scattering mechanisms as a function of the carrier concentration and the temperature was developed and integrated into a device simulator package using a C language interpreter. The model should be useful for heterostructure device simulators such as Blaze.
Aviation kerosene sensors based on nanocrystalline SnO2 thin films with various catalysts
Authors: Kushnarev B O , Maksimova N K , Khludkova L S , Chernikov E V , Sevastyanov E Y
Published: December 2019

Gas-sensitive characteristics of aviation kerosene sensors based on nanocrystalline SnO2 thin films with various catalysts have been studied as a function of the operating temperature and gas concentration in the air. Thin tin dioxide films were grown in magnetron by sputtering of a tin–antimony alloy target in oxygen–argon plasma. It is shown that the sensors are characterized by a high sensitivity to aviation kerosene vapors and by a good stability of parameters during long-term tests and under the variation of humidity.
Formation of Gibbs and Langmuir floating layers based on copper nanoparticles: temperature and concentration effects
Authors: Begletsova N N , Baimagambetova L T , Mironyuk V N , Smirnova A I , Venig S B , Usol ’tseva N V , Glukhovskoy E G
Published: December 2019

This paper is devoted to study of the formation of Gibbs floating layers from aqueous solutions of copper nanoparticles (Cu NPs) stabilized by the sodium dodecyl sulfate surfactant. Langmuir floating layers of arachidic acid formed on the surface of a water subphase containing Cu NPs were also studied. Adsorption of copper nanoparticles on a monolayer of arachidic acid at different conditions has been investigated. In the experiments the amount of copper nanoparticles in the subphase and the temperature of the subphase were changed. The performed analysis showed that the increase of subphase temperature from 29 to 42 °C leads to the increase of the area occupied by Langmuir floating layers in a liquid-condensed state by 30 and 32 %, respectively. After a single transfer of the floating layer onto the highly oriented pyrolytic graphite substrates, their surface microrelief was investigated by atomic force microscopy (AFM). The AFM scans showed that the obtained copper nanoparticles films contained separate areas with copper particles and their aggregates. With an increase of surface pressure from 10 to 40 mN/m, an increase of the height difference of the surface microrelief from 4 to 7 nm and an increase of the large aggregates number with lateral dimensions about 100 nm were observed.
Influence of annealing temperature and activation time on the catalytic centers formation for carbon nanostructures growth
Authors: Il’in O I , Rudyk N N , Il’ina M V , Osotova O I , Fedotov A A
Published: December 2019

Experimental studies of the effect of annealing temperature and time of the PECVD process activation stage on the formation of catalytic growth centers of carbon nanostructures were carried out. The dependences of the diameter and height of the catalytic centers on the annealing temperature are obtained. It has been established that exposure in an ammonia atmosphere leads to additional etching of nickel and a decrease in their diameter and height. It has been established that the most optimal temperature for creating with the smallest dispersion of the geometric parameters of the catalytic centers is 750 °C.
Self-organization of nanocarbon particles in the flame by a heterophase mechanism
Authors: Vasilyeva O V , Ksenofontov S I , Kokshina A V
Published: December 2019

Nanotubes of different structure are formed during the self-organization of nanocarbon particles in the flame. The nucleation and growth of these tubes occurs by a heterophase mechanism. Self-organized structures by size “fill” the space between nano-and micro-formations.
Selection of the design of a hot heat exchanger of an automotive thermoelectric generator for an urban driving cycle
Authors: Shishov K A
Published: December 2019

It is considered for combustion engines to have nearly 60-70% of fuel energy to be dissipated to the environment by the exhaust gases. Automobile thermoelectric generator (ATEG) application is proved to be a solution for increasing vehicle fuel economy by exhaust gas waste heat recovery. The overall efficiency of ATEG system highly depends on its hot heat exchanger, which is designed to remove heat from the exhaust gases to thermoelectric modules that generate electricity. Intensification of heat transfer in ATEG prototypes is usually achieved by using finning and tabulators. However, the modification of inner side of hot heat exchanger increases the hydraulic resistance of the exhaust system, which adversely affects the power and efficiency of the engine. In this work, we investigate the designs of hot heat exchangers with different configurations of the inner surface and evaluate their impact on the engine power during the modern urban driving cycle.
The conductivity and the diamagnetic response of the graphene-like carbon films in the 80 – 120 K temperature range
Authors: Kovalchuk A A , Prikhodko A V
Published: December 2019

The paper presents the results of conductivity and diamagnetic response studies in natural carbon films in the temperature range 77–220 K. The behavior of the current-voltage characteristic of carbon films containing graphene-like fragments was studied by nanosecond voltammetry. It is established that when the critical temperature is reached, the sample resistance increases sharply with the simultaneous disappearance of diamagnetism. Was proposed possible mechanism of high-temperature superconductivity based on synchronization of negative-U centres presumably exists in the carbon structure under study.
Strength and structural properties of AlN films grown on SiC/Si substrates synthesized by atomic substitution
Authors: Grashchenko A.S. , Kukushkin S.A. , Osipov A.V.
Published: December 2019

In the present work, we studied the strength and structural characteristics of the layers of the AlN/SiC/Si heterostructure. The surface morphology of the AlN film and the SiC/Si substrate was studied using atomic force microscopy. The thickness of the AlN and SiC layers was determined by analyzing the data of ellipsometry. The hardness of the films and the substrate was measured by the method of nanoscratch testing. It was experimentally shown that the films under study have a high crystalline quality.
Rainfall Prediction in East Java Using Spatial Extreme Value Theory
Authors: Artha A A , Sofro A
Published: December 2019

Extreme rainfall is a phenomenon that occurs because of the high intensity of rainfall which causes many negative impacts. For example, is flooding that can ruin crops for farmers. To minimize this hazard, rainfall prediction is carried out. One methods that can be used is spatial extreme value theory using max stable approach and copula approach. From it, we will get the return level (predictive value) rainfall by paying attention to the location elements in it. This study discusses the max-stable approach using the Smith model and the copula approach using the Copula Gaussian model. Parameter estimation used is Maximum Likelihood Estimation (MLE) method. Because it takes into spatial elements, the trend surface model is also used. At the end of the study, Akaike Information Criterion (AIC) is used to compare and select the best model that can be used in predicting rainfall. Spatial extreme value theory will be applied to rainfall data in East Java which consists of nine rainfall observation stations. The results of spatial parameter estimation show that the highest of rainfall intensity value will occur around rainfall observation station namely Sawahan which is located in Nganjuk district in a period of two years. From AIC, it can be said that the model using copula Gaussian is the best model compare with max-stable approach as it provides the smallest AIC values.
Two-Level Handling Model of Tuberculosis
Authors: Fuad Yusuf , Maulana Dimas , Astuti Yuliani Puji
Published: December 2019

Tuberculosis (TB) is an infectious disease caused by the Mycobacterium tuberculosis which most commonly attacks the lungs. In 2017, ten million people contracted TB and 1.6 million people died of TB. It is estimated that one million children suffering from TB and 230,000 children die due to TB, including children who die both TB and HIV. Global estimation show that there are ten million TB cases which are equivalent to 133 cases per hundred thousand population numbers, the country with the highest case is India by 27%, China by 9% and Indonesia by 8%. Some research related to the mathematical model of the spread of TB, for example the S-E-I/L model by Soyoung, the S-L-I/J-T model by Zhang, and the S-L-I-T model by Trauer. In this research proposal we will reconstruct a two-level model of the spread of tuberculosis infection, which means that this tuberculosis infection attacks two populations simultaneously, namely adult and individual children. The model used is the S-E-I-R/S-E-I-R model. The first individual who is attacked, in this case is an adult individual, then infects the individual child. Later, we obtain the disease free equilibrium which is

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Analysis between GPA and TOEFL Score For Postgraduate Student of Sports Education using Bivariate Logistic Regression
Authors: Sofro A , Oktaviarina A , Mintarto E , Wiriawan O
Published: December 2019

Due to the globalization era, there is the challenge of competition in all fields including finding work in sports education. To meet the stakeholder’s needs, it is necessary to have some criteria for prospective workers and also a well-planned process in academic. Grade Point Average (GPA), is one of the most important achievements during the postgraduate programme. Meanwhile, another academic component is English as a Foreign Language Test Score (TOEFL) which also has a very significant impact on seeing the job.

This paper will analyze valuable factors that influence GPA and TOEFL using a bivariate approach. In this case, the GPA will be defined as two levels, i.e low and high. TOEFL is also able to define as two categories, i.e more and less than 450. Hence, bivariate logistic regression is the most appropriate approach. The result shows that the coefficient of age has strong evidence to reject the null hypothesis at a significant level of 0.05. It means that the variable of age has a huge contribution to influence the score of the TOEFL for the postgraduate programme in sports education.
Metrics on a G-metric Space
Authors: Jakfar Muhammad , Manuharawati  , Yunianti Dwi Nur , Kumala Mey Dita
Published: December 2019

Given a G-metric space, we offer a simple way to derived metrics from G-metric and realize that any G-metric space is a metric space. We also show that, in certain cases, the metric can be derived from G-metric in such a way that the convergence and completeness in the G-metric is equivalent to those in the derived metric.
Parameter Estimation Using INLA for Disease Mapping of Leptospirosis in Bantul Indonesia
Authors: Artiono R
Published: December 2019

Agriculture sector is recognized as one important factor for an increased risk of leptospirosis in Bantul, Indonesia. From January to July 2010, there were 70 patients of leptospirosis with 43 patients engaged in agriculture. The aim of this study was to determine the impact of agricultural sector on the disease mapping of leptospirosis in district level. A structured additive regression model was used for statistical analysis associated with agricultural area and agricultural livelihood. In addition, a random effect that captures the spatial heterogeneity in the study region was also included in this study. Model estimation and predictive inference was carried out through the implementation of computer code in the R-INLA package, which makes use of the Integrated Nested Laplace Approximation.
Students’ reflective abstraction of middle school in reconstructing quadratic equation concept based on high mathematical ability
Authors: Cahyani L , Masriyah  , Budi Rahaju E
Published: December 2019

A quadratic equation is one of the mathematics concepts that must be learned in secondary school. Students have many difficulties in solving quadratic equations. One of them is experiencing a process skill error. Students need new abstractions and processes to shape experiences to distinguish whether experience falls into student abstraction or beyond student abstraction. Reflective abstraction is students’ understanding of mathematics through problems that reflect and reconstruct mental structures, then the scheme is used to solve problems. The reflective abstraction mechanism that can be applied to metal structures is the APOS theory, namely: Actions, Processes, Objects, and Schemes to construct new mental structures. The process of mental reconstruction of each student is different, so for the formation of mathematical concepts, it needs mathematical abilities. In other words, if someone has good mental reconstruction abilities, hopefully, his concept formation is also good. This research conducted using a qualitative approach. The subject of this research was selected from grade 9 junior high school students in Surabaya. Students must answer two tests, namely tests of mathematical abilities and reflective abstraction tests. Analysis and categorization of scores were carried out on both tests. Then two students who has high mathematical ability was selected as subject. Semi-structured interviews is conducted individually for each subject. The purpose of this study is to find out the reflective abstraction of students that have reconstructing concept of quadratic equations in terms of high mathematical ability. The results of the study indicate that the subject can solve the problem according to the stages of the APOS.
Generalization Pattern’s Strategy of Junior High School students based on Gender
Authors: Firdaus A M , Juniati D , Wijayanti P
Published: December 2019

This study aims to describe the Generalisation Patterns Strategy of junior high school students based on gender. The subject of this study is two junior high school students in Makassar City, one male, and one female. Data collection techniques are written tests and interviews which used to obtain data about the strategy of the generalization patterns of students. The validity used time triangulation. The analysis data consists of three stages: reducing data, presenting data, and daring conclusions. The results of this study show that the male subject used the strategy of Counting, Whole-object-No Adjustment, and Difference-Rate Adjustment. Meanwhile, the female subject used the strategy of Countin and Explicit in the generalization of patterns on numbers and pictures.
Mathematical Connection Middle-School Students 8th in Realistic Mathematics Education
Authors: Hasbi M , Lukito A , Sulaiman R
Published: December 2019

This study was conducted to notice the effect realistic mathematics education in improving 8th grade Middle-School students’ mathematical connection by employing measuring tools of a mathematical connection test and observation sheet, which were developed, was distributed to 37 experimental group students and 37 control group students, which makes 74 learners in total. This study was accompanied experimental by pre-test – post-test control group design. This participant was studying at 8.5th grade as the experimental group and 8.6th grade as the control group from a Middle-School 2 Candi Sidoarjo. Realistic Mathematics Education was implemented in the experimental group while the Control group was implemented to the current Curriculum. As a result of the conducted experimental group, it was being discovered that mathematical connection tests and observation sheets of experimental group students are better than control group students. It was be discovered too, based on the results of the mathematical connection test, 83.78% of students obtained N-Gain more than or equal to 0.7. Therefore, it is possible to say that realistic mathematics education is more efficient than learning in the control group.
Analysis of Mathematical Literacy on Students’ Metacognition in Conic Section Material
Authors: Salsabila E , Rahayu W , Kharis S A , Putri A
Published: December 2019

Mathematical literacy is one of the components that use mathematical concepts and applies them to an everyday situation. Mathematical literacy helps people to identify and understand the role that mathematics plays in the world, and to make the well-founded judgments and decisions required in life by constructive, engaged, and reflective citizens. By contrast, not everybody acquires sufficiently. This study aims to describe the ability of mathematical literacy especially geometry literacy in terms of student metacognition on conic section material. The problems in this study were: 1) How is the ability of mathematical literacy in terms of student metacognition on conic section material 2) What types of mistakes do students make in solving the problem of cone section and 3) What factors cause students to make mistakes in solving conic section question. This research is a qualitative descriptive study. The subjects in this study were 36 mathematics education students who took courses in Analytical Geometry. The data collected using observation, written test, and interview. Before the researcher conducted the analysis, the researcher examined the validity of the data using validity and reliability tests in order to obtain valid data. Furthermore, the valid data were analysed descriptively through identification, grouping, clarification, explanation and conclusion.
Number sequence as a context for creating a mathematical problem
Authors: Prihartiwi N R , Siswono T Y E , Kohar A W , Hartono S , Hidayat D
Published: December 2019

Creating a problem is one cognitive process of Bloom’s taxonomy. By making a problem and the answer on their own, causes students to understand more complex context problems. Applying number sequence challenges students to apply higher-order thinking skills and emphasize exploration, investigation, conjecture, and generalization. From the previous explanation, the purpose of this study is to explore the ability of students in creating mathematical problems in the context of numbers based on the ‘degree of reality’ and based on innovation on mathematics problems. This descriptive explorative study is collected from 24 prospective mathematics teachers that consist of 4 males and 20 females in a university. All students have to answer one question about creating word problems related to number sequence and the answer. Those problems then were analyzed and categorized based on the modification of innovation on mathematics problems by Vistro-Yu and based on ‘degree of reality’ by de Lange. The result of this study, modification is the most emerging technique among all, and the least are addition and replacement. Based on ‘degree of reality,’ only one-fourth of the number of students successful in creating a camouflage context. This result leads to only forth of the number of students successful in creating word problems. The implication of this study is the choice of students in making questions at least provides an overview of the highest level of difficulty, according to students. In mathematics learning, the lecturer should plan assessments and evaluations that need to be developed to build students’ abilities to make mathematics as a whole by connecting subjects in mathematics and to make mathematics more relevant to reality.
The Effectiveness of Learning Materials of Inquiry Models to Practice Science Process Skills in Simple Harmonic Motion’s Matter
Authors: Sholikhah M , Prastowo T , Prabowo
Published: December 2019

This research aims to know the effectiveness of learning materials of inquiry learning models to practicing science process skills in simple harmonic motion’s matter. This research was conducted on 60 tenth grade students at Muhammadiyah 1 Gresik Senior High School. The effectiveness of this research is seen from science process skills tests, learning achievement, and student response. Science process skills data were obtained from pre-test and post-test. Learning outcomes data were obtained from affective and psychomotor assessment through observation methods and cognitive assessment through the post-test method. While student response data were obtained from the questionnaire method. N-Gain values were obtained from average to high range for each class from the results of pre-test and post-test, this showed the increase in process skills of students. The data analysis of learning achievement indicated that all students have final results that meet the minimum completeness criteria (>75). The data analysis of student responses showed positive results, the highest positive response was the use of student worksheets (LKS) that eases students in learning. Thus, based on the results obtained it can be concluded that this research learning instrument is effective for practice the science process skills in simple harmonic motion’s matter.
Development of Guided Inductive Inquiry Learning Support Materials Prototype on Energy for Junior High School Level to Improve Students’ Conceptual Understanding: Validity and Practicality Study
Authors: Mahdiannur M A
Published: December 2019

This research purposed to describe the quality of learning support material prototype in energy topics for Junior High School. The quality-focused on this research were (1) validity and (2) practicality aspects. Guided inductive inquiry (GII) is a learning model to facilitate students to have a comprehensive understanding of concepts, develop complex thinking skills, and help internalize the concept of evidence and substantive concepts within students that they can use to solve problems, develop competencies, and improve learning outcomes. This research used Mafumiko’s Model to develop a prototype of learning support materials based on design research. This study conducted at SMPN 1 Tanah Grogot, Paser Regency, East Kalimantan, and involved 3 (three) subject matter experts (SMEs) and 2 (two) observers during the classroom tryout. The SMEs examined the GII learning support materials valid and their appraisal reliable. The implementation of GII learning support materials during learning processes in the very good category and students’ activities reflected the level of active participation. Based on these results, the quality of the prototype of GII learning support materials on energy topics for Junior High School level met the validity and practicality criteria and also improved the students’ conceptual understanding.
Analysis and empirical research about the satisfaction related factors of business administration specialty practice teaching in Chinese Medicine Universities
Authors: Cheng Xiao , Guan Cuiling , Pan Xiaoyi , Wang Yongjian
Published: December 2019

To study the effects of pre-control, central control and post-test management programs on student satisfaction in management practice teaching in TCM University, 57 students in the experimental class of medical marketing were investigated by test tools like questionnaire and self-made satisfaction scale. There is no statistical difference in student satisfaction (P>0.05), no statistical difference in the sense of knowledge (P>0.05). There are statistical differences in the understanding of content, and understanding is higher than unknown satisfaction (P< 0.05). There are statistical differences in the number of preparatory projects before the internship. The more preparatory projects, the higher the satisfaction (P<0.05). There are statistical differences in the number of internship questions. The more preparatory questions, the higher the satisfaction (P<0.05). Quality and satisfaction of enterprise lecturers were correlated (P<0.05). The factors that affect the satisfaction of practice activities of management practice in Chinese medicine colleges include the content of pre-internship, the number of projects and questions for preparation, and the quality of enterprise lecturers.
Research on brand value improvement strategies of fresh products based on cluster analysis-taking cold fresh meat as an example
Authors: Ye Yanghao , Wang Qing , Liu Shengwen , Huang Yajuan
Published: December 2019

Aiming at the strategies to improve the brand value of fresh products, this paper uses the field research data, official data, public information data in the industry, etc. in the cold fresh meat market as the data basis of the research, and uses cluster analysis to divide the cold fresh meat consumer groups into potential group and main force group, conservative group and follow-suit group. And it uses SPSS and mathematical modeling to analyze the characteristic portraits of the four categories of people, and gives strategies to improve the brand value of fresh products through correlation analysis.
Design of fast digital spectrum stabilization method for UAV radiometry system
Authors: Yang Xiaofeng , Ge Liangquan , Zeng Guoqiang , Yao Zongyi , Yan Lei , Hou Yang , Luo Mingtao , Yu Peng
Published: December 2019

The drone radiation measurement system has a sharp increase in demand for environmental radiation monitoring due to its easy manoeuvrability, low aerial survey cost, high patrol efficiency and no personnel safety concerns. In order to adapt to the fast, flexible and efficient characteristics of the drone, the detector for the Unmanned Aerial Vehicle (UAV) radiation measurement generally consists of a plurality of small-sized detectors to form a detection array. Due to the low single crystal count rate and the influence of electronic system temperature and packaging, many detectors of the UAV radiation measurement system will have “spectral drifts”, which affects the quality of the synthesized spectrum and affects the accuracy of the whole system. Aiming at the characteristics of UAV spectrum measurement system, a three feature point recognition model is established, and the K-40 feature peak (1.46MeV) is approximated by reverse piecewise summation. Thus, the backscattering peaks and characteristic peaks K-40 of the measured spectrum can be obtained to achieve fast spectrum stabilization. Finally, through Gaussian Mixture Model (GMM) peak estimation and experimental validation, the method can obtain the characteristic peak position accurately, and the time between instrument start-up and automatic spectrum stabilization is less than 2 minutes.
Research on image matching algorithm based on improved SIFT UAV
Authors: Guo Rong , Li Shixin , Cai Ruyi , Sun Xiali
Published: December 2019

Aiming at the low accuracy of UAV image registration algorithm, and the complex calculation of SIFT algorithm feature descriptor and the low time efficiency, an image matching algorithm based on improved SIFT is proposed. Firstly, the image of UAV is preprocessed, and the feature point operator is detected by Shi-Tomasi corner, then is extracted by SIFT feature vector, and the dimension of feature vector is reduced by PCA. Then the nearest neighbor method is used for feature matching, and the BBF algorithm is used to search the feature values to improve the matching speed. Finally, the RANSAC algorithm is used to purify the feature points for accurate matching. Experiments show that compared with the traditional image matching method, the proposed algorithm improves the efficiency and accuracy of the UAV image registration technology.
Research on the optimization model of cold chain logistics distribution path under the constraint of carbon emission
Authors: Liao Zhigao , Quan Yuncheng , Jian Kerong , Guo Yi
Published: December 2019

The optimization of cold chain logistics distribution path under the constraint of carbon emission is considered. The restriction of hard time window and carbon emission is added to the model design. The carbon emission is converted into the final objective function of economic cost, transportation cost and goods loss cost in the way of carbon trading price. The problem of energy consumption is considered from the perspective of Economics. The cost of carbon emission is added to the mileage saving method, and the improved algorithm is used to increase the applicability of this kind of algorithm.
Free cash flow and position-related consumption of senior management-based on empirical data of state-owned listed companies
Authors: Tan Xing , Gan Shengdao , Yang Wei , Guo Furong
Published: December 2019

The ultimate owner of the state-owned listed companies is the State, but the State cannot directly participate in the supervision of the managers of the company, so the owner may be “absent” in many state-owned listed companies, leading to excessive position-related consumption of the company’s senior management by using the resources of the company in order to seek personal benefits. When the free cash flow is abundant, the senior management will more intend to put it into their own position-related consumption, resulting in higher agency costs. This article collects the data of A-share state-owned listed companies from 2009 to 2015 as research sample, and empirically studies the impact of free cash flow and the “Eight Regulations” on the position-related consumption of senior management. According to the research, excessive free cash flow will promote the position-related consumption of senior management of state-owned listed companies, resulting in higher agency costs; and in case the enterprise has certain free cash flow, the promulgation of the “Eight Regulations” has a restraining effect on the position-related consumption of senior management in the state-owned listed companies.
Data processing of pulsation signals based on local wave decomposition and teager energy
Authors: Wang Fengli , Cai Yannian
Published: December 2019

Nonstationary and nonlinear signals are often encountered in the research and development of turbomachinery. One such example is the pulsating strain signal measured during engine ramping to find the maximum resonant strain in the application. Because the pulse signal may come from different interference sources, it is difficult to detect weak useful signal in the background of noise. In order to solve this problem, a new method based on local wave decomposition (LWD) and Teager energy is proposed. According to the local characteristics of the vibration signal, the optimal prediction operator of the transformed sample is constructed by selecting the appropriate square error minimization criterion, so that the second generation wavelet basis function can fit the local characteristics of the vibration signal. The adaptive second generation wavelet is used as the prefilter to improve the effect of LWD decomposition. Then the correlation kurtosis is used to select the sensitive internal model function (IMFs). Finally, the Teager energy operator algorithm is applied to the selected sensitive IMF to identify the characteristic frequency. The validity of the method is verified by the measured strain signal of a turbocharger turbine as an example.
Design of the gordon euryale seed automatic shelling machine
Authors: Zhang Junyan
Published: December 2019

In this study, Aiming at the inefficiency of the manual shelling of Gordon Euryale seed, a new automatic seeding Sheller with simple structure and easy operation was developed to improve the efficiency. According to the shape and size of the Gordon Euryale Seed and the material characteristics of its hard shell, the mechanical structure of the machine were designed. It included the feeding mechanism, shelling device and separating device. Experiments showed that it had met the requirements of rapid shell peeling. The shell peeling rate was over 98% and the whole kernel rate was over 97.5%. It had reliable operation, fast speed and low failure.
Application of small sample BP neural network in quantitative analysis of EDXRF
Authors: Li Fei , Tang Zhuoyao , Ge Liangquan , Wu Nanxing , Cheng Feng , Sun Kun
Published: December 2019

Quantitative analysis of EDXRF is affected by matrix effect, randomness of nuclear radiation, interaction of elements, statistical fluctuation of radiation detection process, etc. Its algorithm needs to consider many factors, and the established functional relationship is often a complex non-linear function. Therefore, effective quantitative analysis method has always been the key research direction of spectral resolution technology. In this paper, we use MATLAB software to study the effect of BP neural network in quantitative analysis of EDXRF by establishing the non-linear relationship between the counting rate of each element and the content of a single element in a small sample. The experimental results show that the small sample neural network can establish a stable structure and be applied to quantitative analysis of EDXRF, but the number of samples restricts the accuracy of prediction results, most of which can only guarantee 20% to 30% relative error.
Automatic classification of tongue texture color and tongue coating color based on BP neural network
Authors: Zhang Kang , Zhang Heling , Zhu Mingfeng
Published: December 2019

Tongue diagnosis is an important part of the traditional Chinese medicine diagnosis, and it is one of the main criteria for clinical diagnosis of TCM. Tongue texture color and tongue coating color are the main research contents of tongue diagnosis. This paper first uses computer technology to achieve separation of tongue texture and tongue coating on the tongue image. According to the position information, the tongue texture and tongue coating template are discriminated, and the color information of tongue texture area and tongue coating area are obtained respectively. Finally, the automatic classification of tongue texture color and tongue coating color is realized through neural network.
Research on the characteristics of generations of subway vehicles based on artificial neural networks
Authors: Shao Fubo , Liu Hui
Published: December 2019

Urban rail transit vehicles have become an important part of public transport due to the outstanding advantages: high speed, large traffic volume, low energy consumption and less land occupation. Metro vehicles have been developed for over one hundred years and there are obvious generational characteristics. In this paper, the generational characteristics of metro vehicles are studied from the top index of metro vehicles. First, the paper synthetically analyses 45 specific indicators of four categories: vehicle transport capacity, safety, comfort and environmental friendliness. And then 14 core indicators are extracted via employing the complex network method. Secondly, the first- and second-generation metro vehicles are analysed based on the 14 core indicators. By employing the artificial neural networks, the relationship between the performance and indicators of metro vehicles is obtained. And then the performance of the next generation metro vehicles can be predicted. Finally, the characteristics of the next generation of metro vehicles are predicted based on the performance of the next generation of metro vehicles and the latest technology. The future developing direction of metro vehicles is pointed and the theoretical basis for the next generation of metro vehicle manufacturing is provided in this paper.
Exploring the results of college English learning under the perspective of artificial intelligence
Authors: Cao Ming
Published: December 2019

Based on the theory of output hypothesis and the perspective of Artificial Intelligence (AI), the purpose of present study is to verify the result of applying Virtual Reality (VR) experiment. A quantitative method has been used. 69 students as an experimental group and 68 as a control group, by random sampled, have participated this quasi-experiment. After half a year, experimental group has obtained better performance than control group in CET (College English Test). T-test shows significant differences in the result of CET total score (t=2.05, p<0.05) and listening (t=2.70, p<0.01) as well as writing (t=2.32, p<0.05) section score. These results suggest that applying VR method brought positive result for college English learning.
First process-based simulations of climate change impacts on global tea production indicate large effects in the World’s major producer countries
Authors: Beringer Tim , Kulak Michal , Müller Christoph , Schaphoff Sibyll , Jans Yvonne
Published: December 2019

Modeling of climate change impacts have mainly been focused on a small number of annual staple crops that provide most of the world’s calories. Crop models typically do not represent perennial crops despite their high economic, nutritional, or cultural value. Here we assess climate change impacts on global tea production, chosen because of its high importance in culture and livelihoods of people around the world. We extended the dynamic global vegetation model with managed land, LPJmL4, global crop model to simulate the cultivation of tea plants. Simulated tea yields were validated and found in good agreement with historical observations as well as experiments on the effects of increasing CO2 concentrations. We then projected yields into the future under a range of climate scenarios from the Inter-Sectoral Impact Model Intercomparison Project. Under current irrigation levels and lowest climate change scenarios, tea yields are expected to decrease in major producing countries. In most climate scenarios, we project that tea yields are set to increase in China, India, and Vietnam. However, yield losses are expected to affect Kenya, Indonesia, and Sri Lanka. If abundant water supply and full irrigation is assumed for all tea cultivation areas, yields are projected to increase in all regions.