bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nonlinear Inverse Heat Transfer Problem
Authors: Rysbaiuly Bolatbek , Alpar Sultan 
Published: April 2022

Abstract
In this work, a method for finding nonlinear heat-conducting characteristics of soil is developed. Two-layer complexes of containers were created, the side faces of which are thermally insulated, so the 1D thermal conductivity equation is used. A temperature sensor is placed at the junction of the two media, and a mixed boundary value problem is solved in each area. In order to provide the inverse coefficient problem with initial data, two temperature sensors are used: one sensor was placed at the open border of the container and recorded the soil temperature at this border, and the second sensor was placed at a short distance from the border, which recorded the air temperature. The measurements were carried out in the time interval (0,4t
max
). First, the initial-boundary value problem of thermal conductivity with nonlinear coefficients is investigated by the finite difference method. Two types of difference schemes are constructed: linearized and nonlinear. The linearized difference scheme is implemented numerically by the scalar Thomas method, and the nonlinear difference problem is solved by the Newton method. The solution of the linearized difference problem was taken as the initial approximation of the Newton method. To find the thermophysical parameters, the corresponding functional is minimized using the gradient descent method. In addition, all thermophysical characteristics (8 coefficients) were found for a two-layer container with sand and chernozem.
Safety Analysis of Secondary Cable in Substation during Power Frequency Short Circuit
Authors: Liu Shengjun , Yin Yanzeng , Qi Hongbin , Wang Xuejia 
Published: April 2022

Abstract
In order to study the safy of secondary cables in substation, the influences of soil resistivity, short circuit current, distance, grounding grid parameters and cable parameter on the core-to-sheath potential difference and shielding layer current are investigated. It is shown that the core-to-sheath potential difference and shielding layer current change little with soil resistivity, and increase linearly with the increase of short-circuit current, and decrease with the increase of distance. The core-to-sheath potential difference increases with the increase of side length of grounding grid and cable length.
Design and Implementation of Remote Monitoring System for Rare Trees Based on LoRa Communication
Authors: Xu Chen , Xiaoyue Zheng , Quou Ge , Tao Xu , Xiushan Wu 
Published: April 2022

Abstract
In recent years, rare plants on the earth have gradually disappeared, so it is urgent to inspect and protect their health. A rare tree monitoring system compatible with NB-IOT (Narrow Band Internet of Things) is designed based on the low-power data transmission technology of LoRa (Long Range Radio). The system takes stm32f103c8t6 as the core of the controller, collects information through temperature and humidity sensor, attitude sensor, infrared pyroelectric sensor and sound sensor, builds a server to store the information and data back to the server, uses the terminal to access the server, and reminds the operator when the amount of information exceeds a certain threshold, Finally, the real-time monitoring of rare trees in the field is realized.
Reliability Analysis and Modelling of Containment Spray System Based on Petri Net
Authors: Zhang Ziben , Zhang Dongliang 
Published: April 2022

Abstract
Reliability modelling for digital instrumentation and control systems in nuclear power plants is one of the new trends. The containment spray system in the digital I&C system of nuclear power plant is selected, and the generalized stochastic Petri net model is used to model the reliability of the containment spray system. A single-cycle simulation of the generalized stochastic Petri net model is carried out under consideration of a variety of dynamic events, and the probability of system start-up failure is obtained. The results show that the generalized stochastic Petri net model can well reflect the impact of various dynamic events on system security. Therefore, the generalized stochastic Petri net model is suitable for reliability modelling of I&C systems in nuclear power plants.
An English Pronunciation Quality Evaluation Model Based on Multi-dimensional Features
Authors: Li Yiqun , Huang Guimin 
Published: April 2022

Abstract
As a universal language, English has been paid more and more attention, among which oral English learning is very important. In this paper, the two key technologies of pronunciation error detection and quality evaluation are studied, both of them are effectively integrated, aiming to build a model for L2 learners’ English pronunciation quality evaluation. This paper mainly studies two different methods of pronunciation error detection. Based on the speech recognition framework, the standard score is compared with the threshold to judge the correctness of phoneme pronunciation, and the phoneme-dependent threshold is set to improve the maximum Precision to 0.44. By judging the correct pronunciation and confusing phoneme, the accuracy of pronunciation error detection is improved to 81.26%. This paper proposes the fusion algorithm from multi-dimensions of speech fluency and intonation respectively, and a newly designed feature called word duration ratio, which significantly improve the correlation of pronunciation quality evaluation to 0.746.
Discussion on Zero-dimension Model and Designed Hydrological Conditions in Calculation of Water Pollution Capacity
Authors: Chen Juan , Wang Sen 
Published: April 2022

Abstract
In order to implement the strictest water resource management system and ensure the sustainable utilization of water resources, it is necessary to carry out the work of limiting pollution in water function area. The calculation of water pollution capacity is the basis of pollution limitation in water function area. Code of practice for computation on allowable permitted assimilative capacity of water bodies (GB/T25173-2010) is the main reference basis for the calculation of water pollution capacity. There are some limitations in the practical application. In this paper, the zero-dimensional model is modified based on the current code of pollutant carrying capacity. And the determination of designed hydrological conditions was discussed. This would give reference for the calculation of water pollution capacity.
Experimental Bulging and Buckling of Bi-segmented Cylinders
Authors: Wang Feng , Zhang Jian , Zuo Xinlong , Tang Wenxian , Zhao Tan 
Published: April 2022

Abstract
This paper studies the experimental free bulging and buckling of bi-segmented cylinders. Two cylindrical shells are manufactured using argon-arc welding and analyzed for manufacturing errors. Next, free bulging tests and hydrostatic pressure tests are conducted to verify the feasibility of the free bulging technique and to confirm the destruction form of the bulged bi-segmented barrel. At the same time, the reasonableness of the circular thick plate is examined, which is determined according to the deformation consistency. The results show that the bi-segmented cylindrical preforms exhibit good welding quality by TIG welding technology. It has the same critical pressure load as a single cylindrical preform. Nevertheless, the bi-segmented cylindrical preforms have larger internal volume and better buoyancy capability than the single cylindrical preform. The free bulging bi-segmented shell has good symmetry along the axial direction. It has larger internal volume and higher critical buckle capacities than the non-bulging one.
Security Assessment of the MQTT-SN Protocol for the Internet of Things
Authors: Roldán-Gómez José , Carrillo-Mondéjar Javier , Castelo Gómez Juan Manuel , Martínez José Luis Martínez 
Published: April 2022

Abstract
The Internet of Things (IoT) is growing globally at a fast pace. However, the expansion of the IoT paradigm has brought with it the challenge of promptly detecting and evaluating attacks against these systems. The Message Queuing Telemetry Transport (MQTT) protocol is one of the most used protocols in the IoT scenario due to its lightness. The MQTT-SN protocol, which is an even lighter version of MQTT, is specially designed for embedded devices on non-TCP/IP networks. This paper presents an exhaustive assessment of the MQTT-SN protocol and describes its shortcomings, which can allow an attacker to compromise the security of the entire IoT infrastructure. We have designed 3 different attacks in order to allow us to evaluate the different security impacts on a real MQTT-SN network. All the attacks were implemented and tested, and we show how they work and their impact on performance. Furthermore, a non-attacked scenario was also implemented to allow us to compare the performance of an attacked system with that of system without attacks.
Study on a Compatible Model Combining Point Cloud Model and Digital Elevation Model
Authors: Guo Wenbo , Zhao Jun 
Published: April 2022

Abstract
DEM is an important data source to describe the surface morphology, but it is not a real 3D model, which can not meet the requirements of true 3D description under the ground. LIDAR point cloud data is a new true 3D data with high precision and high density. Based on the analysis of the differences between DEM and point cloud data in acquisition method, data structure and model construction, this paper proposes a 3D point set data model based on regular grid 2D data field, as well as the idea of regional modeling, and tests the feasibility of the data model through the upper and lower boundary modeling method. The experiments show that: (1) the 3D point set data model based on regular grid 2D data field is compatible with complete DEM data and simplified point cloud data, and has good expansibility; (2) the newly-built data model can complete the true 3D modeling of simple underground entity with high efficiency when the amount of data is only doubled; (3) The new data model can be generated by inputting DEM data, point cloud data and simplified algorithm of point cloud data under the same coordinate system. It has the potential of large-scale, multi-scale and automatic output processing, and has a good prospect of popularization.
Resource Allocation Algorithm Based on Modeling of Ubiquitous Network Node Capability
Authors: Song Dai , Chen Xushan , Rui Lanlan , Li Wenjing , Du Zongpeng , Li Zhiqiang , Lu Lu 
Published: April 2022

Abstract
With the continuous development and progress of the Internet, computing power is gradually moving from the center to the edge. In order to perceive, measure, schedule and manage the distributed computing resources, it is necessary to model and evaluate the node capability. Based on the development trend of network computing convergence and the demand of network computing service scheduling, this paper studies the unified measurement model and resource allocation algorithm for the integration of network computing and heterogeneous resources. The node resources are divided into four dimensions: computing, communication, memory and storage, and on this basis, the comprehensive ability evaluation index is proposed. Through simulation analysis, the effectiveness of the resource allocation algorithm based on node capability modeling is verified.
Control Analysis of Propagation Dynamics on Networks
Authors: Zhu Zhiqiang 
Published: April 2022

Abstract
It is generally the dynamic behavior of multiple information in the network. Based on the principle of propagation dynamics and mathematical model, this paper simulates the dynamic process of information in the network, and analyzes the influence of network structure and propagation dynamics on the dynamic behavior of information in the network through the simulation results. By simulating the dynamic process of communication, we find that the location and release time of intervention information in the network will have an impact, and we can control the dynamic behavior of information in the network by controlling the location and release time of intervention information.
Stable Reverse Driving of a Tractor with Multiple Trailers
Authors: Jelenc Blaž 
Published: April 2022

Abstract
We address the problem of the stable reverse driving of a vehicle with multiple trailers. By itself, the reverse driving of a multiple trailer vehicle is highly unstable, so a proper steering control is needed. First, the straight reverse driving is analysed and a stable solution to the problem is explicitly calculated. The solution depends on the specific geometry of the vehicle, namely on the lengths of the tractor and the trailers, and on the set of parameters that determine the rate of convergence of the reverse driving towards the straight reverse driving. We describe two different approaches towards the derivation of the solution of the stable reverse driving. We show that the solution to the problem is uniquely determined and finally we show that the proposed solution can be easily applied to the reverse driving of the tractor along an arbitrary, gently curved, path.
Active Obstacle Avoidance Control Strategy Based on Four-Wheel Steering
Authors: Li Haiqing , Li Sijun , Xia Fuhao 
Published: April 2022

Abstract
Active obstacle avoidance control strategy is the main question of intelligent vehicles, and active four-wheel steering is gradually used in the intelligent control system. Considering both tracking performance and driving characters, an active controller with four-wheel steering (4WS) and active rear steering (ARS) based on adaptive model predictive theory (AMPC) is designed. The control architecture is composed a supervisor and an AMPC controller. The supervisor is used to select the appropriate control mode and the AMPC is used to calculate the expected steering angle when the stability indexes over the safety threshold. Finally, the proposed control strategy is simulated via Carsim-Simulink co-simulation. The results show that the integrated controller can track the obstacle avoidance path and has good driving performance.
Class Specific Dictionary Learning with the Independence Between-class and Dependence Intra-class Coefficient’s Constraint
Authors: Du Yu , Lu Yonggang , Zhao Ligang 
Published: April 2022

Abstract
In the field of image classification, deep learning has become the focus of research. But when the number of training samples is small, especially when there are a large number of intra-class variations in the small samples, the performance of deep learning is often not satisfactory. To deal with the problem, a new dictionary learning method based on sparse representation and an improved coefficient’s constraint is proposed. A general dictionary is learned to eliminate noise signal, and then based on the general dictionary, a class specific dictionary is learned by an improved coefficient’s constraint which maintaining the independence of the dictionary atoms between-classes, while allowing the dependence of the dictionary atoms intra- class. The class specific dictionary combined with the general dictionary is used for the image recognition. Experimental results show that, compared with the state-of-the-art dictionary learning methods, the proposed method usually shows better performance on image classification with small data sets.
Backstepping Adaptive Trajectory Tracking Control of Manipulator with Uncertainties of Model and State
Authors: Liu Yuhang , Zhang Lei , Zhou Jiaxin , Wang Xiaohua , Wang Wenjie 
Published: April 2022

Abstract
In this paper, a backstepping adaptive control method based on Kalman data fusion (KDF-BAC) is proposed to solve parametric and non-parametric as well as state variables in manipulator dynamics model. Firstly, the non-parametric uncertainties are regarded as internal disturbances to simplify the dynamics model of the manipulator. Secondly the backstepping control law is derived using the idea of recursive design, and the adaptive method is used to identify the uncertain parameters to provide the estimated value of unknown parameters for the backstepping control law. Finally, the Kalman data fusion method is used to reduce the uncertainty of the velocity information, and the most reliable estimate value is obtained, which is fed back to the controller. The simulation results show that the proposed KDF-BAC can reduce the influence of manipulator uncertainties on trajectory tracking performance, and has better control effect than adaptive control and backstepping control.
Modelling a Swarm of Delivery Drones for Disaster Relief Utilizing an Organization Approach
Authors: Kolesnikov Valeriy 
Published: April 2022

Abstract
This paper describes an organization-based approach to modelling an autonomous distributed system. This approach simplifies design of such systems and allows for a better understanding of the system overall. Such an approach is applicable for modelling a variety of distributed systems. We demonstrated it for a swarm system of autonomous drones used for disaster relief aid delivery.
Decision-Making Support Software Tools Based on Original Authoring Bayesian Probabilistic Models
Authors: Kozhomberdieva G I , Burakov D P , Khamchichev G A 
Published: April 2022

Abstract
The article presents programs that implement original approaches to group expert rating estimation and fuzzy inference. They implement probabilistic models based on Bayes’ Formula, previously proposed and published in the works of the authors. In these models, the estimated input data are interpreted as evidence in favor of one or another hypothesis from the set of possible ones, determined by the specifics of the model. All the evidence obtained is, in one way or another, transformed into a set of Bayesian conditional probabilities calculated under the assumption that the corresponding hypothesis is true, and the posterior probability distribution on the set of these hypotheses is used as the output. This distribution is used either directly as a result for decision making, or as a basis for calculating the final result. The features of the software implementation of models on the Java platform are discussed, the advantages of the models, confirmed or identified in the process of software implementation, are noted. The developed programs have a convenient graphical user interface and can be used as decision-making support tools to solve applied problems in the field of expert rating estimation and fuzzy inference.
Heart Rate Estimation Algorithm Based on Normalized Least Mean Square combining Complete Ensemble Empirical Mode Decomposition with Adaptive Noise
Authors: Cheng Jie , Yu Chengbo 
Published: April 2022

Abstract
Aiming at the difficulty of extracting heart rate due to the relative movement between human body and acquisition equipment, this paper proposes a Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDA) based on Normalized Least Mean Square (NLMS) adaptive filtering combined with fully adaptive noise sets for heart rate estimation. Firstly, an adaptive filter was used to filter the motion artifacts in the original signal by taking the triaxial acceleration signal as the reference signal. Then, the PPG signal was decomposed by CEEMDAN to obtain a series of Intrinsic Modal Functions (IMF) from high to low frequency. The Permutation Entropy (PE) criterion was used to determine the threshold range of the signal, so as to filter out the high-frequency noise and baseline drift. The results show that the Pearson correlation coefficient between the computed heart rate of PPG signal after noise reduction and the standard heart rate based on ECG signal is 0.742, and the average absolute error percentage is 6.08%, which indicates that the proposed method can accurately calculate the heart rate in the exercise state, and is beneficial to human physiological monitoring under the exercise state.
Study on the Methods to Estimate the Bed Shear Stresses in Yangtze Estuary
Authors: Gu Fengfeng , Lu Hanfang , Wan Yuanyang , Shen Qi , Wang Yuanye 
Published: April 2022

Abstract
High spatial and temporal current resolution velocities were measured by use of an acoustic Doppler velocimeter (ADV) in the tidal bottom layer of North Passage Deep water Navigational Channel (DNC) of Yangtze Estuary in China. And the vertical profiles of mean velocity were measured by using a pulse-coherent acoustic Doppler profiler (PC-ADP). The measured data show the vertical profiles of mean velocity are almost logarithmic. For discussing, the turbulent kinetic energy (TKE) method based on the velocity for ADVs-based is chosen and a new logarithmic profile (LP) method ignoring the influence of complex variation of the parameter Z
0 is suggested to estimate the bed shear stresses respectively. The calculated results show that the bed shear stresses estimated by LP method are larger than the ones estimated by TKE method mostly in Yangtze estuary. At the moment of ebb peak, the maximum error can be about twice occurring and the error of ebb tide is almost greater than the one of flood tide. These phenomena are explained in this study by the deduction of formula for steady and unsteady flow. It is concluded that the vertical logarithmic profile of velocities will be influenced by unsteady flow and there is not the same bed shear stress even if there is the same logarithmic velocity profile in vertical. Generally, this has led to a necessary adjustment of the drag coefficient Cd
of steady flow in flow model to avoid overestimating the bed stress for unsteady flow in estuary based on the observed data.
Active Power Joint Control Strategy for Hydro-wind-solar-storage Multi-energy Complementary Power Supply
Authors: Hu Lin , Shen Jianjian , Wang Yue 
Published: April 2022

Abstract
Compared with a single type of power supply, hydro-wind-solar-storage multi energy complementary system has obvious advantages in active power regulation performance. However, there are also many new problems in terms of coordinated control of multiple types of power supplies and giving full play to the performance advantages of various power supplies. Considering the regulation characteristics of different power supplies and the requirements of shallow charging and shallow discharging of energy storage battery, this study proposes a joint active power control strategy of multi-energy complementary power supply systematically. The basic regulation of hydropower is used to supplement the output of wind and solar power plants, while the compensation regulation of energy storage power supply is used to improve the stability of total output. Additionally, hydropower is used to charge and discharge the energy storage battery. The simulation results show that the proposed strategy can effectively give play to the regulation advantages of different power supplies, and meet the requirements of shallow charge and introduction.
JWST retrieval simulation of super-Earth
Authors: Barbier H , Lopez Izurieta E D , Manzaba Vélez A , Herrería Hoyos D A 
Published: April 2022

Abstract
The James Webb Telescope (JWST), launched at the end of 2021, will permit the study of exoplanets’ atmospheres with an accuracy never obtained before. One of the most keenly anticipated science themes with JSWT data is the study of super-Earth type planets. There exist many questions about their interior and atmospheric composition as well as their evolution and possible migrations.
In this work, we simulated transmission spectra of super-Earth type systems with the petitRADTRANS code and emission spectra of a M-type star with PySynphot. The primary transit observation is simulated with the MIRISim simulator working in the MIRI LRS-Slitless mode. We then obtained the transmission spectra of the planet using a code that we developed ourselves. Finally, we carried out the retrieval: first, in order to check the retrieval tool included in the petitRADTRANS code, we treated the original transmission spectrum. Second, the code is used with the spectrum obtained from the telescope simulator.
The results found encourage us to compare them to results found when using other tools, with the hope of gaining precision in those results, in addition to working in a wider range of wavelengths.