bluuebunny/crossref_metadata_2025 huggingface dataset:
Methodological Approach to the Innovative Development of an Isolated Energy
Authors: Tarasov A E
Published: November 2021

Isolated energy systems serve, as a rule, enterprises of the mining and oil and gas industries with cities and towns. The fight against climate change, which began more than 50 years ago, was marked by the adoption in 2015 of the Paris Agreement on Climate [1] within the framework of the UN Framework Convention [2] and was further developed in Europe - the climate program Fit for 55 was adopted in the European Union [3]. According to the provisions of this program, it is assumed that the climate policy will be toughened by 2030 and 2050. It is planned to achieve zero greenhouse gas emissions into the atmosphere, create an updated system for trading greenhouse gas emissions and introduce cross-border taxes on carbon dioxide emissions starting from 2023 for the supply of goods to the EU countries. Extensive development and lack of modernization of existing isolated energy supply systems will negatively affect the economic attractiveness of the extracted minerals due to increased costs of electricity generated and a tangible cross-border tax on greenhouse gas emissions. The article analyzes methodological approaches to the choice of an innovative way of modernization and the creation of an isolated medium-power power system.
Experience of Using EasyEDA to Develop Training Boards on the PIC16f887 Microcontroller
Authors: Abdrakhmanov V Kh , Salikhov R B , Popov S A
Published: November 2021

A brief overview of computer-aided design (CAD) systems widely used in Russia is presented, and the main requirements for tracing PCB boards are given. The main features of the actively developing cloud CAD system EasyEDA are shown, and the expediency of its use is justified. The idea of creating low-cost electronic training boards based on the PIC16F887 microcontroller for studying the basics of microprocessor technology is presented. Electronic training boards demonstrate all the capabilities of the microcontroller – the operation of the I/O ports, serial port, analog-to-digital converter( ADC), with a two-line liquid crystal display (LCD), with temperature sensors, with a DC motor, with a stepper motor, etc. The experience of developing a budget electronic training boards based on a PIC microcontroller in EasyEDA, which can be used to study the programming of microcontrollers, is shown. Shown are the possibilities of using the jlcpcb.com service to order PCB boards in the largest PCB prototyping enterprise in China, called JLCPCB.
Vector Simulation of Deep-Bar Induction Motor
Authors: Korobeynikov B A , Oppakhodzhaev A M , Sidorov D I
Published: November 2021

The paper considers a mathematical model of a deep-bar induction motor with a squirrel-cage rotor in the generalized vector coordinates.

The transition from the induction motor mathematical in the phase coordinate system to the motor’s vector model in the generalized vector coordinates is shown, which allows obtaining a simpler induction motor model applicable for the analysis of steady-state and transient modes. A new approach to simulating a motor in the form of an electric circuit is not only inductances but also complex resistances interconnected.
Managing Methods Development for the Production Assets of Thermal Power Plants in Conditions of Insufficient Statistical Data
Authors: Lisin E M , Parshina A S , Vasilyeva A A
Published: November 2021

The paper is devoted to the proposal of a method for making managerial decisions on the replacement of production assets of TPPs in conditions of insufficient statistical data on failures and changes in the technical state of an equipment. It is proposed to use a probabilistic method to predict the period of replacement of production assets, based on the formation of a hypothesis about the law of distribution of equipment failures and its reaching the limit state, which determines the stock of possible operating time of a production asset. As an economic criterion for the period of replacement of a production asset, the use of an indicator of production profitability is considered, the advantage of which is the ability to make a decision to change equipment before the expiration of the life resource in the event of an unsatisfactory economic result of its operation, which is critical in solving the problem of ensuring the economic sustainability of TPPs. In the absence of an investment resource for the replacement of a production asset, it will be possible to recommend the conservation of an ineffective asset, which will minimize economic losses.
Estimation of Human Biomechanics during Registration with a Wearable Device
Authors: Grecheneva A V , Dorofeev N V , Goryachev M S
Published: November 2021

In article research of human biomechanics is carried out in the case of registering his movements using a single accelerometer, which is located in a wearable device. Mobile phones, smart watches or fitness bracelets can act as a wearable device. It should be noted that the research is oriented at evaluating biomechanics using a mobile phone, but the results obtained in the form of algorithms and a general approach can be transferred to cases of using other wearable devices.
Requirements for the Procedure for Assessing the Operator’s Person When Processing Accelerometer Data
Authors: Grecheneva A V , Dorofeev N V , Goryachev M S
Published: November 2021

The article considers the possibility of biometric authentication based on gait parameters, which are obtained after intelligent processing of the accelerometer data of a wearable device. The article discusses the main trends and trends in the field of biometric authentication, as well as authentication by gait parameters. The developed neural network algorithm and informative parameters are described in the authentication procedure based on the data of a single sensor of a portable device. The practical verification of the proposed approach is carried out on 32 subjects of different physiology. The results of the study show the possibility of distinguishing their own movements in 100% of cases, and the distinction of the subjects is more than 90%. Also, the final part of the article provides the requirements for the authentication procedure when processing accelerometric data of gait biometrics, the level of trust of the developed algorithm is determined.
Evaluation of the Comparative Efficiency of CCGT in Variable Modes
Authors: Garievskii M V
Published: November 2021

The purpose of the research is to select the priorities for the development of various types of power plants and to substantiate the structure of generating capacities. An improved method has been developed for the selection of priorities for the development of various types of power plants, taking into account the service life and economic performance of the main equipment of power plants in variable modes based on equivalent operating hours. The influence of variable modes of combined-cycle gas installations on the service life of the main equipment (steam and gas turbines) is studied. The comparative efficiency of CCGT-450 in variable modes is calculated, taking into account the wear of the main equipment. As a result of calculations, it was found that with the minimum forecast prices for natural gas, the most efficient power plant (among those considered) is combined cycle power plant, which provides the lowest prime cost of electricity when operating in the base mode and the least increase in the prime cost of electricity when operating in an alternating mode.
Mathematical Emergency Response Model of Rescue Services
Authors: Maximov A V , Matveev A V , Zavodskov G N
Published: November 2021

The growing number of incidents and emergencies around the world is raising the issue of security. To improve security, states allocate huge amounts of money, both to support rescue services, and for scientific research in this area. The article reveals an approach to the development of a mathematical model of the rescue services functioning, taking into account the relationship between its individual types of forces and means, allowing simultaneous optimization of various types of material and human resources.
Interval Approach to Magnetotelluric Data Processing
Authors: Lavrukhin A A , Tukanova A S
Published: November 2021

The article presents a new approach to estimate the frequency characteristics of the impedance tensor for processing magnetotelluric data. The approach is based on the applying of interval analysis methods when solving a system of linear equations. As a reference method, to compare with, a combined robust algorithm is used (with discarding data by the coherence criterion, median estimating, and weighting least squares method). This algorithm is compared with the results of the proposed interval computational algorithm that is based on the method of J. Rohn, implemented in the intvalpy Python library. Computational experiments on the data processing were performed using natural magnetotelluric field data. The interval approach can be successfully applied to the processing of magnetotelluric data.
Modeling the Influence of the Edge Electrostatic Effect on the Transformation Function of Thin-Film Quasi-Differential Capacitive Sensitive Elements
Authors: Mikhailov P G
Published: November 2021

Capacitive sensing elements are the main components of capacitive measuring transducers, which determine most of the metrological characteristics and operational parameters of sensors. First of all, capacitive sensing elements ensure the temporal and parametric stability of sensors, which are the main operational characteristics in such areas as rocket and space and aviation technology, the nuclear industry, in which the instability of sensors and measuring systems based on them can lead to high financial and human losses. etc. At the same time, compensation for lateral capacitive couplings and electrostatic leaks are very important issues, since small changes in capacitance when measuring physical quantities can lead to uninformative measurements in the presence of distortion of electrostatic fields in a capacitive sensing element. In this regard, it is necessary to take into account and simulate the stray fields of electrostatic fields and their influence on measurements.
Determination of the Probability Density Function of the Mixture Signal and Additive Noise under Influence of Multiplicative Noise
Authors: Artyushenko V M , Volovach V I
Published: November 2021

Issues related to effect of multiplicative (modulating) (otherwise amplitude distortions) and additive noises on processed signal are considered. Analysis of statistical characteristics of probability density function (PDF) of instantaneous signal values against background of modulating interference is carried out. Expressions of the joint PDF envelope, phase and instantaneous signal values are obtained, for the case of only phase distortions, as well as the case when fluctuations in amplitude and phase are independent of each other. It is noted that in the second case, with the independence of phase and amplitude distortions, the PDF of the signal, first of all, is determined by the PDF of its instantaneous values and practically does not depend on the PDF of the signal phase. Expressions are obtained for the PDF useful signal and the most common PDF envelope when affecting the signal with modulating noise for deep phase distortions and for its uniform distribution over the interval (0, 2π). In addition, for the case of some functional relationship of phase and amplitude fluctuations, the expression for PDF instantaneous signal values is defined. The presence of such a functional connection allows calculating the PDF of the signal through the statistical characteristics of its envelope. It is obtained that PDF of mixture of signal and additive noise contains arbitrary distribution of phase and amplitude, as well as arbitrary law of distribution of envelope of processed signal. It is obtained that weight coefficients are determined by derivative of characteristic function of amplitude distortion in case when PDFs of said mixture are distributed according to normal law and functional connection exists between amplitude and phase distortions.
Investigation of the Emission Higher Harmonics into the Generator Grid
Authors: Yaroshevich V V , Karpov A S , Fastiy G P
Published: November 2021

The article considers a section of the grid with generator voltage busbars (GRU-10 kV) of one of the hydroelectric power plants HPP-I of a large cascade HPP, which supplies electricity to an aluminium plant via two busbars. It is described that the plant load includes converter units, including: transformers, bridge rectifier blocks and saturation chokes, which are powerful sources of harmonic disturbances. An overview of the developed model and the principles of its construction for studying the influence a powerful non-linear load on the generator is given. Analysis of the results calculations on the model showed that the load of an industrial enterprise creates current and voltage distortions in the electrical s not only of the plant itself, but also in urban grids, and on the busbars of the generator voltage HPP-I. The article analyzes the influence of the current effects of a large industrial enterprise load in asymmetric modes on hydrogenerators by evaluating torsional vibrations and tangential vibrations in generators. It is shown that tangential forces of double frequency (100 Hz) practically do not create significant vibration displacements when the natural frequency of the frontal parts basket is adjusted.
Prospects for Generative - Adversarial Networks in Network Traffic Classification Tasks
Authors: Asyaev G D
Published: November 2021

The paper presents an approach that allows increasing the training sample and reducing class imbalance for traffic classification problems. The basic principles and architecture of generative adversarial networks are considered. The mathematical model of network traffic classification is described. The training sample taken to solve the problem has been analyzed. The data proprocessing is carried out and justified. An architecture of the generative-adversarial network is constructed and an algorithm for generating new features is developed. Machine learning models for traffic classification problem were considered and built: Logistic regression, k Nearest Neighbors, Decision tree, Random forest. A comparative analysis of the results of machine learning models without and with the generation of new features is conducted. The obtained results can be applied both in the tasks of network traffic classification, and in general cases of multiclass classification and exclusion of unbalanced features.
Trajectory Plotting Algorithm for a Self-Driving Road Grader
Authors: Sukharev R Yu
Published: November 2021

The deployment of self-driving technologies occurs in various industries and economic sectors. Self-driving taxi cabs can be found in city streets, in Russia as well as in other countries. The introduction of self-driving technologies in construction, namely, construction machinery, is a promising area that will develop rapidly in the nearest few years. A road grader is the construction machine whose control algorithms resemble those of selfdriving cars the most. One of the first development stages for the self-driving road grader is trajectory plotting.

This article presents the developed trajectory plotting algorithm for the road grader taking into account its design features (minimum turn radius).
Advanced Immersive Capabilities in Virtual Reality Applications Using IMU Sensors
Authors: Kurzaeva L V , Novikova T B , Kornev R , Majorov P E , Borovskikh D I
Published: November 2021

The rapid development of virtual and augmented reality technologies today takes place in almost all areas of activity. The relevance of the study is due to the modern demand for developers to use the latest technologies in the field of game development. Currently, technology is becoming more popular, ensuring that the player is immersed in virtual reality. One of these technologies is a suit with wearable sensors that track the position of a person in space in real time. However, this technology is quite young, but has already gained popularity due to its extensive use capabilities and combinations with other game gadgets. Therefore, at the moment there is a problem of no examples of application development using this technology. This article demonstrates the possibilities of a suit with wearable sensors when creating an entertainment application.
Analysis mastery of concepts physics on the topics of energy for high school students in distance learning during Covid–19
Authors: Heryani T P , Sinaga P , Chandra D T
Published: November 2021

This study aims to analyze the students’ mastery of concepts on the topic of energy during the distance learning when Covid-19 pandemic. The method used in this study is descriptive quantitative. The sampling technique used purposive sampling, where the determination of the study sample is based on gender. The sample in this study is 116 people. Students’ mastery of concepts refers to Bloom’s Taxonomy, namely C1 to C4. The instrument used was a cognitive ability test with 22 multiple choice questions. Data were analyzed using scoring techniques with the Guttman scale. The scores obtained are made into percentages and the results are grouped by category. The results showed that during the distance learning process, the students’ mastery of concepts was in the “enough” category with a percentage of 54%. Based on each aspect, the mastery of the concept in the C1 aspect shows an achievement of 81% with the “very well” category, 49% for the C2 aspect in the “enough” category, 57% for the C3 aspect in the “enough” category and 48% for the C4 aspect with the “enough” category. From the results of the study, efforts are needed to improve students’ mastery of concepts through appropriate learning strategies.
Development of MATTERED (modul of heat and temperature based on android) for senior high school
Authors: Julaila Y , Fauzi A , Wahyuningsih D , Samsudin A
Published: November 2021

Physics is one of the subjects considered troublesome and unique by understudies, so it requires learning media to be able to get the concept of physics. This study points to create a learning module, to be specific MATTERED on Android-based Temperature and Heat for high school understudies. MATTERED is an android-based interactive module with respect to the concept of temperature and heat which is created within the frame of interactive multimedia. This research design uses Research & Development (R&D). MATTERED wasat that point created and approved by material specialists and media specialists, and tried on physics instructors and 90 understudies of class 11th grade in three high schools within the city of Surakarta, Central Java, Indonesia. Based on the comes about of the approval by the material and media master validator, a score of 87.44% was gotten, and the MATTERED trial on instructors and students each obtained a score of 95.03% and 96%, where all appraisals were included within the exceptionally great category. Based on this, it demonstrates that MATTERED is doable to be utilized in learning physics in class for students of class 11th grade.
Developing a Four-Tier Diagnostic Test to identify students’ conception on light and optic topic
Authors: Putri R A H , Widodo A , Rusyati L
Published: November 2021

Students’ conception affects students’ understanding, achievement, and how they relate the concept to others in science. The aim of this study is to develop a four-tier test to diagnose students’ conception on light and optic topics. It is a multiple choice question consisting of the main question, certainty index for the answer, reason, and certainty index for the reason. Light and optic topic is chosen because it is very close to students daily life and is an essential topic at school. This study involves 114 students of grade 10. The instrument was developed from a list of indicators. Once the instrument was constructed, it was tested and analysed using SPSS. The instrument undergoes two stages of validity and reliability test. The first test showed there are 13 out of 19 questions that are valid and reliable with 0.740 Cronbach’s Alpha. The remaining 6 questions were then revised and retested to 21 students of grade 10. The result showed the 6 questions are valid and reliable with 0.829 cronbach’s alpha. Students has medium level misconceptions and they have more scientific knowledge than misconception. In conclussion, 19 questions that are feasible to diagnose students’ conception on light and optic topic.
Digital literacy and cognitive abilities of preservice physics teacher in physics for school course using LMS3: How are the both correlated?
Authors: Rizal R , Rusdiana D , Setiawan W , Surahman E , Ridwan I M
Published: November 2021

The Covid 19 pandemic that hit Indonesia demands the physics for school course to be conducted online using a Learning Management System Supported Smartphone (LMS3). By using this application, prospective physics teachers can practice their digital literacy and strengthen cognitive abilities. This study aims to determine the correlation between digital literacy and cognitive abilities, in general and by gender, which are trained through physics for school course using LMS3. The descriptive research was conducted with survey method and involving 20 students at a university in Tasikmalaya. They are five males and fifteen females spread 18-20 years old. The instruments used in this research were digital literacy test and cognitive ability test. Both have been validated by 5 experts and have high reliability. The collected data were analyzed statistically using the Kolmogorov Smirnov test and the Pearson correlation test. The results of the normality test obtained α = 0.636 which indicates that the data is normally distributed. The correlation coefficient r = 0.626 which indicates that digital literacy and cognitive ability are strong correlated. Based on the results the digital literacy of prospective physics teachers must be adequate to support learning success, one of which is shown by cognitive abilities.
Enhancing students collaboration skills in learning geometrical optics trough the ICARE learning model at Kabawo
Authors: Fatima W O , Sadiyah L H , Siahaan P , Samsudin A , Novia H , Suhendi E
Published: November 2021

This study aims to see the improvement of students’ collaboration skills by applying the ICARE learning model to geometrical optics material. The method used is pre-experimental with one group prettest-posttest design. The sample used study were 31 students of class XI IPA2 with random sampling technique. The main instrument in this research is the researcher himself, while the supporting instrument is a written test in the form of an essay test and analyzed using the rubik’s collaboration skills. To find out the improvement of students’ collaboration skills, it was done by comparing the pretest and posttest scores and then analyzed using N-Gain. Based on the results of research using the ICARE learning model in improving students’ collaboration skills based on the N-Gain value, where the average N-Gain value is 40.05. This shows that students’ collaboration skills have increased in the moderate category after applying the ICARE learning model, while to see the implementation of the learning model using an observation sheet with a score of good category. The recommendation in this study is to pay more attention to the time management allocated for each aspect of ICARE so that each stage in ICARE can be carried out properly.
Developing FD-MT to investigate students’ mental model on fluid dynamic concept: a Rasch model analysis
Authors: Dewi F H , Samsudin A , Chandra D T
Published: November 2021

Fluid dynamics has some complex and unobservable concept, however, tests are rarely developed to measure students’ understanding of these concepts. This condtion make a difficulty to map students’ mental models with existing instruments. Based on that problem, this study aims to develop FD-MT (fluid dynamic-multi tier test) as a diagnostic test for measure students’ mental model on fluid dynamic concept. The ADDIE (Analyzing, Designing, Developing, Implementing, Evaluating) is a research method that used in this study. The data were collected by FD-MT will be analyzed by rasch model analysis, include the reliability, the validity, item fit and the differential item function. Student mental model clasified as Scientific, Synthesis-A (Sy-A), Synthesis-B(Sy-B), Syinthesis-C (Sy-C), Synthesis-D(Sy-D), and Initial. The participant of this study are 20 students in the eleventh grade (9 boys and 11 girls, 16-17 age in average) at high school in Bandung. Based on result study shows that students’ mental model mostly in mental Sc (8.18%), Sy-A (3.18%), Sy-B (21.36%), Sy-C (19.09%), Sy-D (38.18%) and In (10%), and incompleted answer (Nr = 0%). This conclude that, FD-MT is able to measureing students’ mental model on fluid dynamic concept.
The development of moodle based e-learning for newtons’ law in high school physics
Authors: Permana H , Andri B L , Muliyati D
Published: November 2021

Abstrak. This study aims to develop Moodle-Based E-Learning for Newton’s Laws in high school. The research method used is research and development (R&D) with the ADDIE approach. The e-learning was then assessed by media experts, material experts, and physics teachers. The instrument used is a Likert scale questionnaire. The developed model has a lot of interactions with the user as a student activity. The expert and user assessment show this Moodle-based e-learning for Newton’s Laws in high school is suitable for use in physics learning.
Uyo and nanu misconception investigation (UNAMI) on sound-light waves materials in North Sulawesi.
Authors: Umar F A , Samsudin A , Ramalis T R , Sa’diyah LH , Dalila A A , Komalasari K
Published: November 2021

Online learning amid the pandemic made students and teachers incapable to carry out face to face teaching and learning activities. This study aims to measure the state of the conception of students in Mongondow tribe with sound and light waves as material. The research method used descriptive quantitative method. The study was conducted on 67 students (22 male students called Uyo and 45 students who were usually called Nanu). Samples came from three Senior High School in Kotamobagu. The diagnosis of misconceptions was carried out using a four tiers diagnostic test instrument. The analysis in this study used the Rasch analysis. The results of the diagnosis appear that 16% of students in Senior High School in Kotamobagu have misconceptions on the material of sound and light waves especially on interference concept and characteristic sound wave, 39 % of students who get it partially negative understand the concept, only 15% of students who understand it, and 24% of students who don’t understand the concept. Based on this research, it is known that the level of misconceptions and partial negative understand of students is low and medium category.
What do physics teachers need? A need analysis of interactive multimedia to train creative thinking in static fluid
Authors: Susilowati N E , Samsudin A , Muslim
Published: November 2021

The purpose of this study was to analyze the needs of physics teachers in Lampung regarding interactive multimedia. Because many studies have proven the importance of using media in learning, it is necessary to conduct studies to reveal what media are needed to support static fluid learning according to the perceptions of physics teachers in Lampung. The analysis was carried out by providing a needs analysis questionnaire regarding learning media for static fluid material to 32 physics teachers in Lampung. Respondents were physics teachers with educational qualifications for Strata 1 and Strata 2, with 12 male respondents and 20 female respondents. Data presented in descriptive quantitative. Based on the results of the analysis, it is known that 88% of physics teachers need learning media that contains writing, pictures, animation, video, and audio to facilitate various learning styles and can train students’ creative thinking skills during online learning. Based on these findings, it is necessary to develop interactive multimedia to train creative thinking skill on static fluid topic.
Conceptions and troublesome knowledge on acid-base using the two-tier multiple-choice diagnostic test
Authors: Ardianti S , Wiji W , Widhiyanti T
Published: November 2021

Acid-base is one of the materials that tend to be difficult for students to understand. Acid-base is a material that is conceptually solid and requires an integrated understanding of many of the concepts of introductory chemistry. This research is descriptive research that aims to find conceptions of students on acid-base subjects and asking about concepts that are considered troublesome according to their learning experiences. The subjects of this research were 31 students of class XI IPA 4 at SMAN 3 Pariaman. The instruments in this research are diagnostic tests and interviews. The result of this research is the students of SMAN 3 Pariaman have difficulties in learning about the acid-base subject with high category. The percentage of conceptions experienced by students in each indicator is 56.3% of students understand the concept, 20.8% misconception, and 22.9% do not understand the concept. In the second indicator, 45.2% of students understood the concept, 18.3% had misconceptions and 36.5% did not understand the concept. In the 3rd indicator, 35.5% of students understood the concept, 31.2% had misconceptions and 33.3% did not understand the concept. In the 4th indicator, 21.9% of students understand the concept, 27.7% do not understand the concept and 50.3% do not understand the concept. Meanwhile, the acid-base theory, the calculation of pH or pOH, and the relationship between the degree of acidity (pH) and the degree of ionization (a), and the acid equilibrium constant (Ka) or the base equilibrium constant (Kb) are considered troublesome knowledge because they can be conceptually difficult.
Mathematical model of referral marketing strategy
Authors: Putra D P W , Rudhito M A
Published: November 2021

A marketing strategy is an attempt to campaign for a product so that information about the product becomes viral. Advertising strategy began to be combined by involving customers to campaign for the company’s products. This marketing strategy is known as the referral marketing strategy. Viral information in a community can be analogous to the pandemic condition of a disease. This study aims to examine the relationship between the epidemiological model and the marketing model with a referral strategy. This research is a literature study with the results of a marketing model design with a referral strategy. Based on the research, there are 4 groups in marketing modeling with a referral strategy, namely Unaware, Potential Broadcaster, Broadcaster, and Inert. The epidemiological model that is suitable for this condition is the SEIR model. Adjustments to the SEIR Model need to be made because the dynamics of the Unaware can go directly to the Inert because of the trust factor in marketing information. The simulation results show that the parameters that have an important role in making information viral are the customer network and the incubation time of the information becoming viral.
Fixed point theorem with contractive mapping on C*-Algebra valued G-Metric Space
Authors: Wijaya A , Hariadi N
Published: November 2021

Banach-Caccioppoli Fixed Point Theorem is an interesting theorem in metric space theory. This theorem states that if T : X → X is a contractive mapping on complete metric space, then T has a unique fixed point. In 2018, the notion of C
*-algebra valued G-metric space was introduced by Congcong Shen, Lining Jiang, and Zhenhua Ma. The C
*-algebra valued G-metric space is a generalization of the G-metric space and the C*-algebra valued metric space, meanwhile the G-metric space and the C
*-algebra valued metric space itself is a generalization of known metric space. The G-metric generalized the domain of metric from X × X into X × X × X, the C
*-algebra valued metric generalized the codomain from real number into C
*-algebra, and the C
*-algebra valued G-metric space generalized both the domain and the codomain. In C
*-algebra valued G-metric space, there is one theorem that is similar to the Banach-Caccioppoli Fixed Point Theorem, called by fixed point theorem with contractive mapping on C
*-algebra valued G-metric space. This theorem is already proven by Congcong Shen, Lining Jiang, Zhenhua Ma (2018). In this paper, we discuss another new proof of this theorem by using the metric function d(x, y) = max{G(x, x, y),G(y, x, x)}.
Characterisation of signal-induced noise in Hamamatsu R11265 Multianode Photomultiplier Tubes
Authors: Andreotti M. , Capelli S. , Cavallero G. , Chiozzi S. , Cotta Ramusino A. , D'Ambrosio C. , Fiorini M. , Franzoso E. , Frei C. , Gallorini S. , Gambetta S. , Giugliano C. , Gotti C. , Gys T. , Keizer F. , Maino M. , Malecki B. , Minzoni L. , Mitchell S. , Neri I. , Petrolini A. , Piedigrossi D. , Robertson G. , Sergi A. , Simi G. , Slazyk I. , Smith M. , Webster J. , Wotton S.A.
Published: November 2021

Signal-induced noise is observed in Hamamatsu R11265
Multianode Photomultiplier Tubes, manifesting up to several
microseconds after the single photoelectron response signal and
localised in specific anodes. The mean number of noise pulses varies
between devices, and shows significant dependence on the applied
high-voltage. The characterisation of this noise and the mitigation
strategies to perform optimal single-photon counting at 40 MHz, as
required by the LHCb Ring-Imaging Cherenkov detectors, are
reported.
Design a H-bridge low ripple and high bandwidth air core magnet corrector power supply in NSRRC
Authors: Wong Y.-S. , Huang J.-C. , Liu K.-B. , Liu C.-Y. , Wang B.-S.
Published: November 2021

This paper is the study of a low-current-ripple and
high-bandwidth corrector power supply. The main circuit of this
power supply is using a full bridge (H-bridge) structure, and the
output current through the high-precision direct current current
transducers (DCCT) to transfer the reference voltage to the
controller. Previous TPS corrector power supply had a 4.7 kHz
current bandwidth, and its output current ripple was
100 μA. Such current ripple and bandwidth do not satisfy the
requirements of a rapidly orbiting feedback system of air core
loading. Therefore, our research team designed a novel prototype
power supply with a high bandwidth (more than 10 kHz) and low
output current ripple (less than 10 μA) which was developed
via a novel topology circuit. The operation frequency of the main
power switch's n-type metal-oxide-semiconductor logic of this novel
circuit is increased to 245 kHz. Moreover, the output results of
the filter inductor and filter capacitor are modified to
80 μH and 2.46 μF, respectively. The prototype power
supply bandwidth reached 10.546 kHz and increase of 124% and its
output current ripple was lowered below than 5 μA. The
properties of this corrector power supply are very important for the
beam correction in storage rings. Finally, A circuit with an input
voltage of 48 V, a maximum output current of 10 A, and an output
power of 400 W is tested in a laboratory to verify the performance
of the developed corrector for the National Synchrotron Radiation
Research Center.
Linkages between GRACE water storage, hydrologic extremes, and climate teleconnections in major African aquifers
Authors: Scanlon Bridget R , Rateb Ashraf , Anyamba Assaf , Kebede Seifu , MacDonald Alan M , Shamsudduha Mohammad , Small Jennifer , Sun Alexander , Taylor Richard G , Xie Hua
Published: November 2021

Water resources management is a critical issue in Africa where many regions are subjected to sequential droughts and floods. The objective of our work was to assess spatiotemporal variability in water storage and related controls (climate, human intervention) in major African aquifers and consider approaches toward more sustainable development. Different approaches were used to track water storage, including GRACE/GRACE Follow On satellites for Total Water Storage (TWS); satellite altimetry for reservoir storage, MODIS satellites for vegetation indices, and limited ground-based monitoring. Results show that declining trends in TWS (60–73 km3 over the 18 yr GRACE record) were restricted to aquifers in northern Africa, controlled primarily by irrigation water use in the Nubian and NW Saharan aquifers. Rising TWS trends were found in aquifers in western Africa (23–49 km3), attributed to increased recharge from land use change and cropland expansion. Interannual variability dominated TWS variability in eastern and southern Africa, controlled primarily by climate extremes. Climate teleconnections, particularly El Nino Southern Oscillation and Indian Ocean Dipole, strongly controlled droughts and floods in eastern and southern Africa. Huge aquifer storage in northern Africa suggests that the recent decadal storage declines should not impact the regional aquifers but may affect local conditions. Increasing groundwater levels in western Africa will need to be managed because of locally rising groundwater flooding. More climate resilient water management can be accomplished in eastern and southern Africa by storing water from wet to dry climate cycles. Accessing the natural water storage provided by aquifers in Africa is the obvious way to manage the variability between droughts and floods.
Microplastics interact with benthic biostabilization processes
Authors: Hope J A , Coco G , Parsons D R , Thrush S F
Published: November 2021

Marine microplastics (MPs) accumulate in sediments but impacts on ecosystem functions are poorly understood. MPs interactions with stabilizing benthic flora/fauna or biostabilization processes, have not been fully investigated, yet this is critical for unraveling MPs effects on ecosystem-scale processes and functions. This is also vital for understanding feedback processes that may moderate the stock and flow of MPs as they are transported through estuaries. The relationships between sedimentary MPs, biota, environmental properties and sediment stability from field sediments, were examined using variance partitioning (VP) and correlation analyses. VP was used to identify common and unique contributions of different groups of variables (environmental, fauna and microplastic variables) to sediment stability. The influence of microplastic presence (fragment/fiber abundances and microplastic diversity) on sediment stability (defined using erosion thresholds and erosion rates) was demonstrated. Furthermore, MPs appeared to mediate the biostabilizing effects of environmental properties (including microorganisms) and fauna. Environmental properties and sediment stability could also explain the variation in MPs across sites suggesting biostabilizing properties may mediate the abundance, type and diversity of MPs that accumulate in the bed. The potential for MPs to influence biota and biostabilization processes and mediate microplastic resuspension dynamics within estuaries is discussed.
Deep in the Sierra Nevada critical zone: saprock represents a large terrestrial organic carbon stock
Authors: Moreland Kimber , Tian Zhiyuan , Berhe Asmeret Asefaw , McFarlane Karis J , Hartsough Peter , Hart Stephen C , Bales Roger , O’Geen Anthony T
Published: November 2021

Large uncertainty remains in the spatial distribution of deep soil organic carbon (OC) storage and how climate controls belowground OC. This research aims to quantify OC stocks, characterize soil OC age and chemical composition, and evaluate climatic impacts on OC storage from the soil surface through the deep critical zone to bedrock. These objectives were carried out at four sites along a bio-climosequence in the Sierra Nevada, California. On average, 74% of OC was stored below the A horizon, and up to 30% of OC was stored in saprock (friable weakly weathered bedrock). Radiocarbon, spectroscopic, and isotopic analyses revealed the coexistence of very old organic matter (OM) (mean radiocarbon age = 20 300 years) with relatively recent OM (mean radiocarbon age = 4800 years) and highly decomposed organic compounds with relatively less decomposed material in deep soil and saprock. This co-mingling of OM suggests OC is prone to both active cycling and long-term protection from degradation. In addition to having direct effects on OC cycling, climate indirectly controls deep OC storage through its impact on the degree of regolith weathering (e.g. thickening). Although deep OC concentrations are low relative to soil, thick saprock represents a large, previously unrealized OC pool.
Litter origins, accumulation rates, and hierarchical composition on urban roadsides of the Inland Empire, California
Authors: Cowger Win , Gray Andrew , Hapich Hannah , Osei-Enin Jasmine , Olguin Salvador , Huynh Britney , Nogi Hinako , Singh Samiksha , Brownlee Stanley , Fong Jonathan , Lok Trevor , Singer Gideon , Ajami Hoori
Published: November 2021

Urban areas are the primary source of human-made litter globally, and roadsides are a primary accumulation location. This study aimed to investigate how litter arrives at roadsides and determine the accumulation rate and composition of roadside litter. We monitored select roadsides in the Inland Empire, California, for litter abundance (count) and composition (material, item, and brand type). Receipt litter with sale time and location information was used to investigate whether wind, runoff, or human travel were dominant transport agents. Only 9% of the receipts could have experienced runoff, and wind direction was not correlated with receipt transport direction. However, human travel and receipt transport distances were similar in magnitude and distribution, suggesting that the displacement of litter from the place of purchase was predominantly affected by human travel. The median distance receipts traveled from the sale location to the litter observation location was 1.6 km, suggesting that most sources were nearby to where the litter was found. Litter accumulation rates were surprisingly stable (mean 40 349 (33 255–47 865) # km−1yr−1or 1170 (917–1447) kg km−1yr−1) despite repeated cleanups and the COVID-19 stay-at-home orders. A new approach was employed to hierarchically bootstrap litter composition proportions and estimate uncertainties. The most abundant materials were plastic and paper. Food-related items and tobacco products were the most common item types. The identified branded objects were from the primary manufacturers (Philip Morris (4, 2%–7%), Mars Incorporated (2, 1%–3%), RJ Reynolds (2, 1%–3%), and Jack in The Box (1, 1%–3%)), but unbranded objects were prevalent. Therefore, identifiable persistent labeling on all products would benefit future litter-related corporate social responsibility efforts. High-resolution monitoring on roadsides can inform urban litter prevention strategies by elucidating litter source, transport, and accumulation dynamics.
A model for gauged skyrmions with low binding energies
Authors: Cork Josh , Harland Derek , Winyard Thomas
Published: November 2021

We consider gauged skyrmions with boundary conditions which break the gauge from SU(2) to U(1) in models derived from Yang–Mills theory. After deriving general topological energy bounds, we approximate charge 1 energy minimisers using KvBLL calorons with non-trivial asymptotic holonomy, use them to calibrate the model to optimise the ratio of energy to lower bound, and compare them with solutions to full numerical simulation. Skyrmions from calorons with non-trivial asymptotic holonomy exhibit a non-zero magnetic dipole moment, which we calculate explicitly, and compare with experimental values for the proton and the neutron. We thus propose a way to develop a physically realistic Skyrme–Maxwell theory, with the potential for exhibiting low binding energies.
Bootstrapping Bloch bands
Authors: Tchoumakov Serguei , Florens Serge
Published: November 2021

Bootstrap methods, initially developed for solving statistical and quantum field theories, have recently been shown to capture the discrete spectrum of quantum mechanical problems, such as the single particle Schrödinger equation with an anharmonic potential. The core of bootstrap methods builds on exact recursion relations of arbitrary moments of some quantum operator and the use of an adequate set of positivity criteria. We extend this methodology to models with continuous Bloch band spectra, by considering a single quantum particle in a periodic cosine potential. We find that the band structure can be obtained accurately provided the bootstrap uses moments involving both position and momentum variables. We also introduce several new techniques that can apply generally to other bootstrap studies. First, we devise a trick to reduce by one unit the dimensionality of the search space for the variables parametrizing the bootstrap. Second, we employ statistical techniques to reconstruct the distribution probability allowing to compute observables that are analytic functions of the canonical variables. This method is used to extract the Bloch momentum, a quantity that is not readily available from the bootstrap recursion itself.
The feasibility of Indonesian potato’s farming and its global competitiveness
Authors: Swastika D K S , Saptana  , Gunawan E
Published: November 2021

Potato’s farming in Indonesia is thought to be profitable. However, its competitiveness in global production is questionable. The purpose of this study is to analyze the financial feasibility of potato’s farming in Indonesia and its competitiveness in global production. The data used were the results of National Farmers Panel (PATANAS) surveys in 2008, 2011 and 2017. The cost and benefit analysis were used to analyze the financial feasibility. In addition, productivity and producer price were used to measure its global competitiveness. The results showed that potato’s farming during the period of 2008 to 2017 was highly profitable. The R/C ratios were high and continued to increase. These results showed that potato’s farming in the study area is profitable and feasible to be done. In contrast, although potato’s farming in the study area is very profitable, it has no competitiveness in global production, due to the relatively low yield and high cost shown by producer price. The highest cost component was seed. Therefore, there should be a significant effort to find out the efficient use of seed, as well as to increase the capacity of farmers in producing good quality seeds efficiently. It is a challenge for breeding research to produce potato’s varieties with higher yields than currently exist in Indonesia. Another challenge is the research on the use of cut seed into pieces with minimum of two shoots per section.