bluuebunny/crossref_metadata_2025 huggingface dataset:
A retrospective observational study of critically unwell patients retrieved from Thames Hospital between April 2018 and December 2020
Authors: Miller Rory , Bell Samuel , TenEyck Lisa , Topping Meg
Published: August 2021

ABSTRACT INTRODUCTION In New Zealand, critically ill patients who present to rural hospitals are typically treated, stabilised and transferred to facilities where more appropriate resources are available. AIM The aim of this study was to describe patients who presented critically unwell and required retrieval from Thames Hospital in the Waikato region. METHODS Notes were reviewed retrospectively for patients who were retrieved from Thames Hospital between 1 April 2018 and 31 December 2020. Patients were excluded if they were retrieved from the offsite birthing centre or their notes were not available to the authors. RESULTS During the study period, 56 patients were retrieved by intensive care teams based at Waikato, Starship or Auckland Hospitals. Patients had a median age of 57 years and most were female (60.7%). Māori patients were over-represented in the retrieval cohort compared with the population presenting to the emergency department (30.4% vs. 20.1%, P < 0.001). We found that 41% of patients presented after-hours when there was only one senior medical officer available on site and 70 procedures were performed, including rapid sequence induction, which was required by 19.6% of patients. DISCUSSION This study describes a population of critically unwell patients who were retrieved from a rural hospital. The key finding is that nearly half of these patients presented after-hours when there was only one senior medical officer available on site. This doctor also has sole responsibility for all other patients in the hospital. We recommend that referral centres streamline the retrieval processes for rural hospitals.
Macroalgal calcification and the effects of ocean acidification and global warming
Authors: Yang Fangfang , Wei Zhangliang , Long Lijuan
Published: August 2021

Calcification by calcified marine macroalgae is crucial to algal growth and the formation and maintenance of coral reefs. It involves complex processes, such as the uptake, transport and storage of Ca2+, HCO3– or CO32–, and the formation of crystals responsible for calcium deposition. Calcification is vulnerable to changes in global climate, including ocean acidification and warming. Studies investigating the mechanisms of macroalgal calcification are limited and restricted to physiological processes; however, the use of new approaches, such as genomics, provides avenues for new understandings. Here, we review the literature on macroalgal calcification from physiological to molecular levels and present a list of key issues that need to be resolved in order to understand the mechanism of calcification. This review offers insights into the potential effects of changing climate conditions on algal calcification to provide an accurate prediction of future changes in reef ecosystems.
Gaia Pigino: Inside the cell
Authors: Morgado-Palacin Lucia
Published: August 2021

Gaia Pigino studies the molecular mechanisms and principles of self-organization in cilia using 3D cryo-EM.
No more glowing in the dark: how deep learning improves exposure date estimation in thermoluminescence dosimetry
Authors: Mentzel F , Derugin E , Jansen H , Kröninger K , Nackenhorst O , Walbersloh J , Weingarten J
Published: August 2021

The time- or temperature-resolved detector signal from a thermoluminescence dosimeter can reveal additional information about circumstances of an exposure to ionising irradiation. We present studies using deep neural networks to estimate the date of a single irradiation with 12 mSv within a monitoring interval of 42 days from glow curves of novel TL-DOS personal dosimeters developed by the Materialprüfungsamt NRW in cooperation with TU Dortmund University. Using a deep convolutional network, the irradiation date can be predicted from raw time-resolved glow curve data with an uncertainty of roughly 1–2 days on a 68% confidence level without the need for a prior transformation into temperature space and a subsequent glow curve deconvolution (GCD). This corresponds to a significant improvement in prediction accuracy compared to a prior publication, which yielded a prediction uncertainty of 2–4 days using features obtained from a GCD as input to a neural network.
Management and regulatory supervision of legacy sites and radioactively contaminated lands in Republic of Kazakhstan
Authors: Tazhibayeva Irina , Klepikov Alexander , Romanenko Oleg , Blynskiy Alexander , Sergazin Gumar , Ermatov Abdumalik , Zhunussova Tamara , Sneve Malgorzata
Published: August 2021

The safe management and disposal of radioactive waste (RW) arising from the nuclear legacy, as well as newly generated RW, are key problems. Their solution will have important implications for nuclear energy development, the introduction of other radiation technologies, and their public perception. In the framework of the cooperation between the Committee of Atomic and Energy Supervision and Control (CAESC) of the Ministry of Energy of the Republic of Kazakhstan and the Norwegian Radiation and Nuclear Safety Authority (DSA), work has been carried out to analyse the current state of nuclear and radiation safety in the Republic of Kazakhstan. The analysis was based on identifying gaps in national legislation and the assessment of corresponding threats in this area. Proposals for their elimination were developed, taking into account international experience and International Atomic Energy Agency recommendations. Analysis of the current situation in the Republic of Kazakhstan showed that at present the RWs are not properly regulated within an up-to-date regulatory framework. Currently, a list of key by-laws is being developed, which will support the provisions of a new law on RW management, and work is underway to adopt the already developed and drafted regulatory documents. Within the framework of the CAESC-DSA cooperation, the priority tasks established for 2021–2024 include the development of regulatory documents for the rehabilitation of uranium heritage sites, site selection for new nuclear facilities, and the management of nuclear materials for certain types of installations and manufactures. Practice has shown the need to use the advanced international experience and common approaches developed internationally, to develop and apply long-term and reliable solutions for the management of RW and nuclear legacy facilities and territories. The solution of these problems concerns not only scientists, technologists, and employers of the nuclear industry, but requires their cooperation with politicians, regulatory authorities, and the general population. The importance of sharing international experience to understand and solve these challenges is highlighted.
On the effects of strain gradients on spinodal decomposition
Authors: Petsos George
Published: August 2021

When the molar volume of a binary solid solution depends on composition, composition fluctuations are accompanied by strain fluctuations. In order to describe the process of spinodal decomposition in these systems, we develop a coupled one-dimensional elastodiffusion model that takes account of the developed coherency strains and their gradients. Based on this model we examine the effects of the developed strain gradients on the stability of the solution.
Enhanced preconditioner for JOREK MHD solver
Authors: Holod I , Hoelzl M , Verma P S , Huijsmans GTA , Nies R
Published: August 2021

The JOREK extended magneto-hydrodynamic (MHD) code is a widely used simulation tool for studying the non-linear dynamics of large-scale instabilities in divertor tokamak plasmas. The code is usually run with a fully implicit time integration allowing to use large time steps independent of a CFL criterion. This is particularly important due to the strong scale separation between transport processes and slowly growing resistive modes in contrast to fast time scales associated with MHD waves and fast parallel heat transport. For solving the resulting large sparse-matrix system iteratively in each time step, a preconditioner based on the assumption of weak coupling between the toroidal harmonics is applied. The solution for each harmonic matrix is determined independently in this preconditioner using a direct solver. In this article, a set of developments regarding the JOREK solver and preconditioner is described, which lead to overall significant benefits for large production simulations. The developments include the implementation of a complex solver interface for the preconditioner leading to the general reduction of memory consumption. The most significant development presented consists in a generalization of the physics based preconditioner to ‘mode groups’, which allows to account for the dominant interactions between toroidal Fourier modes in highly non-linear simulations. At the cost of a moderate increase of memory consumption, the technique can strongly enhance convergence in suitable cases allowing to use significantly larger time steps, and thus improving the overall time performance by more than a factor of 3.
Real Time Face Recognition using Effective Supervised Machine Learning Algorithms
Authors: Nagaraj P. , Banala Rajesh , Krishna Prasad A.V.
Published: August 2021

In security authentication systems, face recognition has become an emerging new trend. Modern FR processes can detect whether the individual is real (live) or not through face recognition, thus preventing the systems from being compromised by displaying an actual person’s image. These new systems of face recognition are the result of recent advances in the field of computer vision and efficient algorithms for machine learning. This thesis describes in depth how the identification of a real time face can be order to create a safety alert framework for the workplace, the machine learning algorithm Haarcascade classifier was used to build four distinct classes for identification of security equipment and eventually identify the faces in both images and video using python open CV. Initially, face detection technique is performed to scan the face identity marks through.
Hjorth Parameter based Seizure Diagnosis using Cluster Analysis
Authors: Arjaria Siddhartha Kumar , Chaubey Gyanendra , Shukla Nishtha
Published: August 2021

The health-related issues have been increased with a wide range in few years. Hence the need for effective and advanced health care systems or aids isexpanding. New methodologies and instruments must be developed to aid the doctors inintelligent health caring of patients. Biomedical signals are a rich source of information, and it is not easy to understand by the normal human beings. To provide ease, extraction and analysis of biomedical signals can help get the correct information to everyone. The signals generated by the brain control the status of the mind and control the action of the whole body. Epilepsy is a disease by which around 50 million people are affected worldwide. Abnormal synchronisation of the neural activity with symptoms like convulsion is the phenomenon of epileptic seizures. An advanced seizure diagnosis system will help in the detection and diagnosis of epileptic seizures. In this paper, clustering algorithms are applied to Electroencephalogram (EEG) data to classify it in normal and epileptic seizures using the Hjorth parameters. After extracting the Hjorth parameters from EEG signals and k-means, basic sequential algorithmic scheme (BSAS), partitioning around medoids (PAM), fuzzy c-means (FCM), and Vally-Seeking clustering algorithms are applied to group it into normal and seizure. With the used dataset, the Vally Seeking clustering algorithm gives the best performance with an accuracy of about 87%.
A security enhancement for the two way clustering algorithm for image mining
Authors: Jaya Ram M , Vyaya Bhaskara Reddy V
Published: August 2021

Image mining is one of the mining technique which is used for the mining of the image from the huge databases. The Image mining is used in the various sectors for the prospective use of the mining techniques. The increase in the data theft become one of the biggest challenge for the image repositories. This paper proposes the security architecture for the image repositories which is used for the image mining. The salient featured algorithm called as Imago-Sec Algorithm is proposed and used for the efficient providing of the security to the image repositories which is used for the image mining. The relative mining technique is used for the mining of the data from the image database. The Proposed algorithm is a homomorphic token algorithm which uses a single key contribution for both the encryption and decryption of the data in the image databases. The experimental results thus follow which provides that efficiency and throughput of the security that is being implemented.
Cloud data security and various security algorithms
Authors: Tyagi Kanika , Yadav S.K , Singh Mayank
Published: August 2021

The term Cloud computing is a most trending and promisingtechnology. It is the most basic need for many organizations. Cloud technology has many advantages as user can access the files from anywhere over the internet. It has also a very known feature of using the resources according to their demand and user does need to pay extra charges for the unused resources. In Cloud Computing user do not need to carry all their documents with them as cloud access is global. But as Cloud computing means sending data over internet so sometimes there may be security issues and threat of intruder attack at the time of data transmission. As traditional banking industry is totally changed and now the total control in the hand of customer rather than the bank. In banking industry cloud computing provides various features viz; cost saving, business continuity, business agility and time saving. but as data in bank is the most crucial data so cloud security is the first priority for every bank before adopting cloud. security at cloud is the biggest obstacle for the banking industry to adopt this trending technology and its services. So there is need to provide security to the cloud. This paper aims on cloud basic methodology and analyze some security algorithms and their applicability in cloud banking environment.
Parasitic sorority of speech processing algorithms with an assortment of statistical toolkits
Authors: Sudhakaran Prathibha , Yadav Ashwani Kumar , Karamchandani Sunil
Published: August 2021

Speech is a one-dimensional quasi non-stationary time varying signal produced by a sequence of sounds. Speech signals are random in nature. Speech signals are easily corrupted by noise so recognition is an important role in speech processing. Many researches have designed recognition system with challenging parameters. Speech corpus can vary from environment, region, dialects, age, rate at which words are spoken. Pre-processing is the first step which includes framing, de-noisingand filtering. This paper focuses on speech techniques and statistical open source tools such as HTK, Julius, CMUSphinx and Kaldi. The word error rate obtained using all the toolkits on WSJ1 corpus gives us a clear understanding that Kaldi stands out as the most advanced recipes and scripts for speech recognition systems. An Indian English corpus by IITM was implemented in Kaldi yeilds WER of 6.41 and has been compared to other indian and international languages and well known corpuses.
Black Start Operation using a MMC based HVDC system
Authors: Sudarsana Reddy K. , Vigneshwar R. , Tripathi Anushka , Soundharya S P , Kirthika Devi V. S.
Published: August 2021

Blackouts could occur due to various faults and in order to keep the power stations running constantly to avoid consumers losing power a backup plan is necessary. Black start is the process of restoring power to the electric power stations. The Modular Multilevel Converter (MMC) topology has been propitious technology in High Voltage DC (HVDC) system. The research in MMC technology has significantly increased. The MMC based HVDC system has many advantages when compared to the other technology based HVDC system. In this paper, Black Start Operation using a MMC Based HVDC system is proposed to provide continuous power to the load for a certain period of time within which alternative methods of power generation can be made ready. The paper also provides a mathematical model of a continuous equivalent circuit of the MMC Phase Leg. The efficiency of the proposed idea has been verified by MATLAB/Simulink Software and discussed.
Integration of Machine Learning Techniques in Virtual Wireless Sensor Network for insect monitoring
Authors: Hussain Mohammad Equebal , Hussain Rashid
Published: August 2021

Agriculture industries are comparatively slow in adopting emerging technologies than any other industries despite lot of exciting research. The use of Wireless sensor network (WSN) is very important role in agriculture for more productive and sustainable growth. The structure of WSN is tightly application dependent. Every WSN have sensors, processing unit, low frequency radio wave transmitter and power supply using battery. With increasing number of interconnected WSN devices, there is substantial increase in data generation. It contains both control messages as well as application dependent data, collected by the sensors. The collected data are frequently sent to the nearest centralized controller for further processing and decision making. For continuous functioning of WSN, uninterrupted power supply is needed. Many researches are carried out to overcome these challenges. In this manuscript we are proposing a simple and effective machine learning techniques combined with pause and play method to increase battery life of WSN. This could be achieved in three stages play-pause-play (PPP) model. First by gathering data for some time (play mode), Second by putting WSN to sleep (pause mode), in the backend, apply machine learning algorithm that helps to build model from training data to predict the future data. At the final stage, put WSN back to play mode. Compare the result with actual data and fine tune the model to reduce the error. Using this method WSN will get enough sleep time to increase overall life by simulating the normal behaviour of sensor node. The sleep time will be calculated dynamically.
Hybrid Approach for Identification of Manhole and Staircase Using Image Processing
Authors: Sravani Jadala , Vaishnavi Adigiri , Durga Peruri Sravani , Kumar Ashwani
Published: August 2021

The main aim of this research paper is to provide multi security for the pedestrians/older using smart stick using IOT and GPS. This stick having IOT, voice module and attached with multiple sensors to provide high security to the blind peoples while walking. Now a day’s safety is main important cause to the peoples while walking or driving and many more places. This smart stick provides the high security and show way to walk, by using this system we can monitor the blind person position using web application/mobile application and also we can get emergency alert message along with exact location. This system has obstacle sensor, water sensor and MEMS sensors, so that it can detect obstacles sizes automatically and gives voice alert. By using water sensors, it can detect the floor condition is dry or wet and shows the way to walk. In case of any emergency person suddenly fall at floor/any place then this system immediately detects using MEMS tilt sensor and automatically send the message to respective numbers with location and also gives buzzer alarm continuously to alert the neighbours. So that this smart stick can be very useful to peoples to show correct path while walking on the floor or steps and many more places. In this paper, the system can be interconnected with the microcontroller and alert the respective persons when any emergency occurs. This tracking system is composed of a GPS receiver, Microcontroller. The Microcontroller processes this information and this processed information is sent to the respective numbers using web page.
Characterization of Flexible Patch Antennas on Planar and Curved Surfaces
Authors: Khan Habeeba , Ali Sayyed Arif , Wajid Mohd , Alam Muhammad Shah
Published: August 2021

This paper analyses patch antennas operating at 16 GHz on flexible Kapton polyimide substrate in various shapes, namely rectangular, circular, pentagon, hexagon, heptagon, and octagon. Their applications in medical areas, more particularly in wearable devices for E-health, are targeted. The bending effects of these antennas are studied, more specifically on gain, return loss, radiation characteristics, bandwidth, and beamwidth. A detailed comparison results showed that the rectangular patch had better performance even under the bending when the diameter of the surface is varied from 40mm to 120mm and maintains a gain of 4.8 dB at the given frequency. Under such extreme bending, the antennas operate satisfactorily with an efficiency of 43.424% to 47.41%.
Creation of architectural forms by combining additive and information technologies
Authors: Bogodukhova E S , Britvina V V , Bobrova E O , Gavrilyuk A V , Sorokin A Y
Published: August 2021

This work is devoted to the integration of advanced technologies of the modern industry for the creation of construction objects and architectural forms, as well as the development trends of this direction in the construction industry. The aim of the work is to modernize building methods for the construction of building and architectural structures by combining additive and information technologies. An empirical analysis of the construction industry market identified the main intra-industry development priorities affecting the formation of the industry, and a comparative analysis of “traditional” and additive manufacturing showed the advantages of digital technologies. The study of foreign experience has confirmed the relevance of the introduction of additive technologies into production practice. This article presents a 3D project “Digital manufacturing 2030” aimed at obtaining a positive effect from the implementation of layer-by-layer growing of complex building forms using computerization. The data proving its economic feasibility and social significance for the development of urban infrastructure and improvement of the standard of living are presented. Moreover, the percentage of “classic” and additive construction shows the effectiveness of the proposed development. The article is supplied with graphic materials and tables, as well as a detailed description of each stage of the study.
Development of a simulation model to research environmental index of a GTP-110 gas turbine operating as part of a combined cycle gas turbine power unit under changing operational and external climatic factors
Authors: Muravev I K , Kosyakov S V , Muraveva T E
Published: August 2021

Combined-cycle technologies to produce electrical and thermal energy are the most popular and promising all over the world. Their efficient application, however, has encountered a number of interdisciplinary problems. The present study was carried out on a mathematical model of a CCGT power unit. The results of the study are presented, allowing us to assess the impact of operational and environmental parameters on the stability of the combustion process in the combustion chamber of a GTP-110 gas turbine unit, and to determine the compatibility of environmental indicators with the standards for gas turbine operation with a wide range of loads, taking into account the technological and design constraints of thermal mechanical equipment. The main implementation features of a simulation model of a gas turbine unit (GTU) in the SimInTech dynamic modeling environment are considered.
Technologies of embedded project-based learning for undergraduate engineering students
Authors: Bazhenov R , Sabirova V , Samorukov A , Berseneva S , Beknazarova S
Published: August 2021

The purpose of the research is to develop a technology for incorporating project work in undergraduate engineering student training. A pedagogical experiment was conducted in the regional universities of Russia, the Kyrgyz Republic, and Uzbekistan in 2017-2021 among second-, third- and fourth-year engineering students. 126 students and 14 educators took part in it. To achieve the research goal, the authors used project-based learning, the authors’ technique for changing the content of the subject, and the questionnaire method. The authors designed the surveys in the Google forms service and processed the results with MS Excel. According to the experiment results, it can be argued that the successful implementation of project work in training is available through six techniques determined from the ratio of the time spent on face-to-face and independent study on the subject or learning and extracurricular activities. All the participants of the pedagogical experiment evaluated the techniques positively.
Methods of intelligent results ranking for the intermediate assessment of knowledge in mathematical disciplines
Authors: Masina O N , Petrov A A , Druzhinina O V , Shcherbatykh S V
Published: August 2021

We are developing methods of intelligent ranking of results for the intermediate assessment of knowledge on mathematical disciplines within the framework of a hybrid intelligent learning environment functioning. An extended structural diagram of a hybrid intelligent learning environment is presented and the methodology of forming a knowledge base is characterized. The study of new models of the pedagogical process is carried out using intelligent technologies. Clustering problems are solved and algorithms for analyzing test results based on the use of machine learning methods are proposed. The results of the proposed algorithms implementation are presented. The results of this study are of practical importance both for the development of methods for assessing knowledge in mathematical disciplines, and for identifying the abilities of students to research activities.
3D-printed Net-Structured Porous Capacitive Sensors Based Upon Silver-Coated-Glass Fiber-Filled Polymer Composites
Authors: Huang Pei , Cao Yingze , Xia Zhidong , Chen Shaosong , Wang Pengfei
Published: August 2021

Flexible sensors modified with microstructures possess excellent high sensitivity and ultralow detection limit. In this study, silver-coated-glass fiber-filled silicon rubbers with their net structures were 3D printed and designed. Porous structures were introduced through the multi-layer printing of the net structure. The high conductivity of the printed composites originated from the conductive fillers, which assure the composites applied in circuit connection. Flexible capacitive sensors were further fabricated with the porous composites as electrode layers and the flat polyethylene terephthalate film as the middle dielectric layer. The prepared capacitive sensors owned an excellent sensing property to detect ultralow load with a sensitivity of 0.0666 kPa−1. The evolution of the porous structure was schematically described, when the capacitive sensors were compressed. The net-structured porous capacitive sensors fabricated with 3D process would inspire us a new branch in the printing electronics.
Applications of Molten Pool Visual Sensing and Machine Learning in Welding Quality Monitoring
Authors: Sun Meiling , Yang Mingxuan , Wang Binrui , Qian Lijuan , Hong Yuxiang
Published: August 2021

On-line monitoring of welding quality is very important to the realization of intelligent welding technology and has become a research hotspot in the field of welding technology. This article reviews the research results and latest research progress of welding quality on-line monitoring based on molten pool visual sensing in recent years. First, it introduces the characterization of welding quality by the two-dimensional geometric features and three-dimensional topographic features of the molten pool in detail, and then analyzes the application of machine learning and feature engineering in the online prediction of welding status; we discuss the deep neural network and welding quality at the end Convergence of online detection technology. The work done in this paper reviews the progress of online monitoring technology for welding quality and provides a basis for the follow-up work.
Simulation Analysis of Transmission System of Module Propellant Storehouse Based on ADAMS
Authors: Huang Wenkuan , Yang Liu , Guan Jiawei
Published: August 2021

A virtual prototype of the transmission system of a module propellant storehouse is established in ADAMS simulation environment. First, dynamic analysis of the key parts of the transmission system, mainly clutch, is carried out. Then, the 3D model needs to be simulated is established in Solid Works. Finally, combined with the macro commands in ADAMS, the virtual prototype model of the transmission system is established in ADAMS, which can complete the dynamic simulation of the whole loading process. In the simulation process, the parameters are adjusted and optimized to meet the actual situation. The simulation results are analyzed and verified, which can provide some reference basis for the design and selection of driving motor, electromagnetic clutch and other key parts of the transmission system.
An Analytical Method for Plane Elasticity Problems Involving Circular Boundaries
Authors: Jiang Zhizhen , Zhang Rui , Gong Shiyu , Hou Jiahui , Jin Xiaoqing
Published: August 2021

Complex structure with circular boundaries is commonly used in engineering practice, and it is essential to conduct a detailed analysis of the interior stress field of the structure. The Michell stress function is a well-known general solution for plane elasticity problems in the polar coordinates, particularly when circular boundaries are involved. This work presents an analytical method with the assistance of the Michell solution, which could be seamlessly combined with Fourier analysis. Using the expansion of Fourier series, problems with arbitrarily distributed loads can be handled via a standard procedure. A complete analytical solution is elaborated for an arbitrarily loaded circular ring, and a classical elastic solution is provided for verification.
Numerical Simulation of Rigid Projectiles Penetration into Concrete Targets with Different Warhead Shapes
Authors: Zhang Xuguang , Li Wenbin , Wang Xiaoming
Published: August 2021

When the projectiles with different head shapes impact and penetrate the concrete targets, the resistances of the target plates to the projectiles are significantly different, which is manifested by the time history curve of different accelerations, velocities and the penetration depths of the projectiles, resulting in the obvious differences of the penetration ability of the projectiles to the targets with a same compressive strength. In order to determine the influence degree of projectiles with different head shapes on the penetration ability, ANSYS/LS-DYN is adopted. The finite element numerical simulation software is used to simulate and analyze the three kinds of rigid projectiles: oval (including double oval and oval), conical (including double conical and conical) and cone oval. Among them, the projectiles all penetrated C40 concrete cylindrical targets vertically at an initial velocity of 700m/s. The results show that the penetration ability of the optimal oval, conical and cone oval projectile is gradually reduced, and the highest penetration ability is the oval projectile numbered as dan001, whose final penetration depth is 539cm.
Finite Simulation of Deformation Mechanism of a Perforated Plate and Applications
Authors: Hong Xuanyu , Hu Xiaoyi
Published: August 2021

In recent years, new metamaterials emerge one after another in various fields with various functions, showing a bright future for the development of metamaterials. Negative Poisson’s ratio material is one of the promising materials. It has a wide range of applications in mechanical engineering, acoustics and architecture science. This paper attempts to explore the different deformation mechanisms and possible applications of perforated plate materials with negative Poisson’s ratio. Finite element analysis is used to simulate a typical perforated plate structure, which shows negative Poisson’s ratio effect and abundant deformation forms in vibration condition. In addition to the existing applications in vehicle buffering and building noise reduction, this paper proposes that the perforated plate can be used as a filter screen for water treatment, as well as the filter screen of air purifier. In addition, it can also be used to cultivate precious herb seedlings. Intersects with the medical field, it can even manufacture the vascular embolization treatment device, which can ensure that the longitudinal does not contract and scratch the blood vessel when the blood vessel is opened. On the basis of this study, we can further study the special properties of metamaterials and solve the specific problems in various applications.
The Conjecture of the Essence of Gravitation
Authors: Xie Qibin
Published: August 2021

The purpose of this paper is to explore the causes of universal gravitation, and the law that the gravitation produced by the motion of matter and the absolute dead matter has no mass was put forward. Combined with Newton’s law of universal gravitation, Einstein’s equation of mass loss, cosmic expansion phenomenon, black hole phenomenon, matter infinitely separable theory and so on, this paper discusses the essence of gravitation. Through universal gravitation, electric field force, magnetic field force and quantum entanglement phenomenon, the concept of wave-point force is put forward, and a theory of gravitation law is obtained, that is, the forces of different wave points do not interfere with each other. Combining dark matter and cosmic expansion, the hypothesis of dark matter gravity law is put forward. Finally, some conclusions are summarized, and this paper puts forward some conjectures.
The Nonlinear Propagation and Interaction of Ultrashort Pulses in High-Speed Optical Fiber Transmission Systems in Optics
Authors: Zhou Haoran
Published: August 2021

The fourth-order dispersive nonlinear Schrödinger (FODNLS) equation can simulate the nonlinear propagation and interaction of ultrashort pulses in high-speed optical fiber transmission systems in optics. In this paper, all traveling wave solutions of the envelope are obtained by means of the polynomial complete discriminant system and the elementary integral method. Under specific parameters, the propagation modes of all solutions are given. In this paper, by using the direct integration method, all traveling wave solutions of the envelope of the equation are given, including the singular rational solution, the singular periodic solution, the solitary wave solution and the double periodic solution.
Thermal Emissivity Measurement with Two-temperature Method
Authors: Ying Yunbin , Li Qiang , Kaur Sandeep , Ghosh Pintu
Published: August 2021

Thermal emissivity is one of the most important indices used to evaluate thermal emission capability of an object and is essential for characterization of thermal emitters, especially in the field of infrared thermal emission engineering for various applications, including personal thermal management, radiative cooling and heat preservation, infrared stealth, and infrared encryption. However, due to the natural background thermal emissions from the ambient environment and experimental setup, conventional methods generally ignore the background emissions while keeping the temperature of the radiating sample significantly higher than the ambient temperature. Here, we introduce a simple method that enables accurate measurement of emissivity of a given sample without necessitating high temperature through elimination of background emission noise by the difference of the measured emission signals of the sample at two different temperatures.
Vanadium Oxide Nanoparticles Doped Polymer to Modulate Thermal Emissivity
Authors: Zhu Zehao , Li Qiang , Pattanayak Arnab , Ghosh Pintu
Published: August 2021

Vanadium oxide (VO2) finds a wide range of applications owing to its excellent reversible phase change properties. We demonstrate a method for doping a polymer with VO2 nanoparticles towards realizing a thermal emissivity modulation device, which is expected to supplement the conventional preparation of VO2 film layers using magnetron sputtering, vapor deposition, and such techniques which are relatively cumbersome and expensive. The comparison of thermal emissivity modulation ability of VO2 film membrane structure on silicon substrate obtained by magnetron sputtering and pressed tablet sample obtained from VO2 nanoparticles reveals that the latter also demonstrates substantial thermal emissivity modulation ability. Furthermore, the emissivity of this fabricated PDMS-VO2 blended sample can change from 0.90 to 0.71 in a heating test. This provides us a new technique to fabricate a scalable, cost effective, and widely applicable thermal emissivity modulation device.
Numerical Simulation and Experimental Research of Flow Resistance Characteristics of East Lower Tungsten Divertor Module
Authors: Tian Kun , Li Lei , Yao Damao , Han Le , Xu Tiejun , Zhuang Qing , Yang Lei
Published: August 2021

During long-pulse plasma operation with high power in tokamak, excessive heat load on divertor may lead to material melting or erosion of the first wall material, which enhances impurity radiation and degrades plasma performance. As an important component of the first wall, divertor cooling system is important for the high power and stable operation of the device. The Experimental Advanced Superconducting Tokamak (EAST) is committed to achieving more than 400 s long-pulse H-mode operations, which is equipped with a first wall of full metal. The 10 MW/m2 heat load on divertor means a big challenge for the continuous operation of the system, but the current divertor cannot meet the conditions, so it needs to be upgraded. In order to check whether the cooling water system of the new divertor in EAST can meet the requirements, a fluid test was built to measure the flow rate and flow drop of the divertor. The results show that the difference between the test results and the results of ANSYS-based simulation is 9 %, and the maximum difference between the results of the comparison of two different model parts is 3 %. It is concluded that the cooling water system of the divertor in EAST can achieve the heat load and safety requirements.
Numerical Analysis of Heat Transfer and Flow Field for CFETR Divertor
Authors: Tian Kun , Li Lei , Yao Damao , Xu Tiejun , Han Le
Published: August 2021

Nuclear fusion is now the ultimate need for energy, tokamak is one of the possible devices for controlled nuclear fusion. Based on the advanced tokamak magnetic confinement configuration and the research results of fusion physics in recent decades at home and abroad, Chinese Fusion Engineering Test Reactor (CFETR) will carry out innovative physical design to achieve the international requirements. Divertor is an essential component of the magnetic confinement fusion device, which directly sustains the strong particle flow and high heat load. The cooling system of divertor will directly affect whether divertor can function properly. In this paper, a new structure of divertor suitable for CFETR is designed and simulated, both the flow field analysis and the heat transfer analysis of the model were verified. The results show that the designed divertor structure can meet the system requirements.
Optimizing the classification ability of CNN for SAR fully polarized radar data based on DCGAN
Authors: Bu ZeCong , Zhang Yue , Zheng AnMai
Published: August 2021

In recent years, the deep learning network is widely used. In the field of remote sensing images, due to the high cost of image acquisition, there are still too few training samples, which greatly limits the application of deep learning in SAR data classification. This paper proposes a method that is generating simulated SAR image by generative adversarial network, and uses the image as the training data of convolutional neural network. Aiming at the impact of the simulated images generated by DCGAN’s generator on the classification of convolutional neural networks. The results show that DCGAN can fully extract the main features of the image, and the convolution model based on DCGAN can make CNN have better classification ability and get rid of the dependence on the sample size. CNN can also make full use of simulation data. Whether it is test data set or random dataset, its F1 score can obviously surpass the classification ability without DCGAN’s simulated data. In experiments with different sample numbers, the highest F1 score is 93.6479 in the dataset with DCGAN’s simulated data. In another experiment, its F1 Score reached 87.32, higher than the dataset without DCGAN’s simulated data.
Extraction and inversion of two-dimensional spectrum parameters based on TDIP data
Authors: Gao Zhu , Luo Runlin , Xiang XianLi , Xia Zhengxia , Zhao Zhifeng
Published: August 2021

Conventional TDIP can only obtain two parameters: apparent resistivity and polarizability, so it is difficult to interpret the effective information of ore bodies with high precision, especially the symbiotic and associated ore bodies with little difference in resistivity and polarizability, such as pyrite and carbonaceous limestone, while the spectral parameters (cm and τ) can quantitatively evaluate the abnormal characteristics of mineralized bodies and are rich in geoelectric information. Based on the field apparent resistivity observation mode of Cole-Cole model, the charge rate values of symmetrical quadrupole arrangement of two typical mineralized bodies are calculated by finite element method forward simulation from the 2D point source, this paper puts forward a method for extracting the corresponding spectrum parameters from the chargeability value of TDIP data and verifies the effectiveness of the method.The results show that the abnormal shape is obvious and is consistent with the actual model parameters, which can reflect the spectral parameter characteristics of each abnormal body, realize spectral imaging, and provide a favorable basis for further division of polarization abnormal bodies. This method has been applied to the TDIP data processing of a lead-zinc mine in Wuzhou City, Guangxi Province and good results have been obtained.
Preliminary assessment of BeiDou Navigation Satellite System satellite orbit determination accuracy and positioning accuracy
Authors: Hu Yutao , Meng Zhijun , Jiang Yi , Zeng Zhe , Wang Guangming
Published: August 2021

Orbit determination accuracy and positioning accuracy are two key indexes to assess the performance of navigation system. With frontal positioning methods put forward, the effect of orbit determination accuracy on positioning accuracy is decreasing. In this paper, three main positioning methods provided by BDS is introduced, and the influence of BDS orbit determination accuracy on the results of single point positioning, differential positioning and precise point positioning is respectively deduced. After that, data from two receivers set at Beijing and Chengdu is analysed to evaluate orbit determination accuracy and positioning accuracy. Apart from several extreme values, BDS satellites radial orbit errors are within 1.5m, tangential orbit errors are within 2m and normal orbit errors are less than 5m. Accuracy of single point positioning differential positioning and precise point positioning is 1.9m 1.2m and 0.3m, respectively. Effect of orbit determination accuracy on single point positioning is significant. On the other hand, orbit determination accuracy has less effect on differential positioning accuracy and precise point positioning.
Design and Realization of Test System for Digital Input and Output Module
Authors: Lv Meimei , Ou GuoFeng , Sun Zhentao
Published: August 2021

Aiming at the problems of the various types of digital input and output modules in the anti-harsh hardened computer, the lack of a dedicated test system and the incomplete testing, a dedicated digital input and output test system with a wide test range was designed. The system is based on single-chip microcomputer and FPGA and can provide 64 channels of digital output (0∼30V adjustable), 64-channel digital or voltage value input test, 64 channels of switch-type digital signal, and the status of the tested module can be read in real time through the host computer software. The digital input and output modules can solve the current situation of incomplete functional testing, and the test results are accurate, stable, and reliable, with a compact structure and multiple test channels.
Numerical Simulation Study on Turbulent Heat Transfer Characteristics of Supercritical Fluid in Micro-Fin Tubes
Authors: Gaoxiang Ma , Yanglong Duan
Published: August 2021

In consideration of the technical requirements for compact and efficient heat-exchange equipment in industrial fields, such as sludge incineration heat utilization, solar thermal power generation and aerospace, this paper analysed the supercritical nitrogen flow and heat transfer processes in square straight micro-fin tube, triangle straight micro-fin tube and smooth circular tube under different Re numbers, and obtained the changes in velocity field, local turbulence intensity, average Nusselt number and resistance coefficient of supercritical fluid in micro-fin tubes. Moreover, it was found that the introduction of micro fin was able to improve the turbulent heat transfer performance of supercritical fluid in tubes within certain Re number range.
Research of PD transfer ratio analysis of converter transformer IPVD test based on distributed parameters
Authors: Yu Xinru , Jia Pengfei , Wu Chao , Deng Junyu , Zhang Shuqi , Cheng Huanchao
Published: August 2021

In the process of factory test of converter transformer, the withstand voltage test with partial discharge is usually used to judge whether the internal insulation structure is in good condition or not. If there is no partial discharge, the insulation is in good condition. There are tens of thousands of insulation materials in UHV converter transformer, and the winding structure is complex. If partial discharge is detected during the withstand voltage test, it is impossible to locate the discharge position quickly and accurately. In this study, by analysing the partial discharge signal transmission relationship in the withstand voltage test of converter transformer, combined with the partial discharge signal transmission model of converter transformer winding based on distributed parameters, the partial discharge area in the converter transformer winding is calculated and judged. This method can be applied to the IVPD test of converter transformer to assist in locating the partial discharge area in the winding, greatly shorten the time of fault diagnosis and location of converter transformer, and enhance the scientificity and effectiveness of the test.
Probing the distribution of redox in the diffusion layer of the substrate electrode by the scanning electrochemical microscopy
Authors: Guo Haixia , Shao Huibo
Published: August 2021

Taking advantage of the dual working electrodes and the precise positioning of the tip electrode of the scanning electrochemical microscopy, the distribution of ferrocenemethanol in the diffusion layer of the substrate electrode is studied when the substrate potential is applied. When the co-directional potential is applied to the substrate, the closer to the surface of the substrate electrode, the less the amount of ferrocenemethanol. Because the reaction of the substrate electrode and the tip electrode is the same, they compete with each other. When the reverse potential is applied to the substrate electrode, the closer to the surface of the substrate electrode, the more the amount of ferrocenemethanol. Because the reaction of the substrate electrode can regenrate ferrocenemethanol.