bluuebunny/crossref_metadata_2025_split huggingface dataset:
PJB-Lab: practicing 4C skills in physics practicum
Authors: Firmansyah Juli , Suhandi Andi , Setiawan Agus , Permanasari Anna 
Published: February 2022

Abstract
This article explains how the project-based lab (PJB-Lab) trains critical thinking skills, creative thinking skills, communication skills and collaboration skills (4C Skills) and produces two project products from the application of the fluid concept, namely the application of Archimedes’ law on submarine projects and the application of hydrostatic pressure on the project’s hydraulic pumps (Hydram). This study uses a quasi-experimental method involving 112 students studying at two universities located in the province of Aceh, Indonesia. The results of the study show that 4C skills can be improved well with an increase in the high category. Therefore, PJB-Lab has been proven to be effective in facilitating and training the 4C skills of prospective physics teachers at universities and can be considered for application with students in schools.
Falling faster than g, exponentially
Authors: Cross Rod 
Published: February 2022

Abstract
Calculations are presented showing that the usual ‘faster than g’ demonstration has a surprising property. That is, a rod hinged at its bottom end rotates at an exponentially increasing rate until it falls with maximum vertical acceleration, unlike an object that falls freely by gravity alone. If the rod is hinged at its top end and released from a horizontal position, then the vertical acceleration is a maximum at the instant it is released.
Factors affecting the arterial to end-tidal carbon dioxide gradient in ventilated neonates
Authors: Williams Emma , Bednarczuk Nadja , Dassios Theodore , Greenough Anne 
Published: February 2022

Abstract

Objective. To determine factors which influenced the relationship between blood carbon dioxide (pCO2) and end-tidal carbon dioxide (EtCO2) values in ventilated, newborn infants. Furthermore, to assess whether pCO2 levels could be predicted from continuous EtCO2 monitoring. Approach. An observational study of routinely monitored newborn infants requiring mechanical ventilation in the first 28 d after birth was undertaken. Infants received standard clinical care. Daily pCO2 and EtCO2 levels were recorded and the difference (gradient: ∆P-EtCO2) between the pairs were calculated. Ventilatory settings corresponding to the time of each blood gas assessment were noted. End-tidal capnography monitoring was performed using the Microstream sidestream Filterline H set capnograph. Main results. A total of 4697 blood gas results from one hundred and fifty infants were analysed. The infants had a median gestational age of 33.3 (range 22.3–42.0) weeks and birth weight of 1880 (395–5520) grams. Overall, there was moderate correlation between pCO2 and EtCO2 levels (r = 0.65, p < 0.001). The ∆P-EtCO2 for infants born less than 32 weeks of gestation was significantly higher (1.4 kPa) compared to infants born at greater than 32 weeks of gestation (0.8 kPa) (p < 0.001). In infants born at less than 32 completed weeks of gestation, pCO2 levels were independently associated with EtCO2, day after birth, birthweight and fraction of inspired oxygen (FiO2) (model r
2 = 0.52, p < 0.001). Significance. The results of end-tidal capnography monitoring have the potential to predict blood carbon dioxide values within the neonatal population.
Thermoelastic responses in a nonlocal infinite solid with a circular cylindrical cavity due to a moving heat supply under the MGT model of thermal conductivity
Authors: Mohammed Wael W , Abouelregal Ahmed E , Atta Doaa , Khelifi F 
Published: February 2022

Abstract
Since the non-local continuum theory includes additional information regarding the long-range forces of molecules and atoms, the external length scale parameter may be included in the formulation of physical and engineering modeling. In this study, a new non-local thermoelastic model is presented in which the size-dependent effect has been included in the equations of motion and constitutive relations. To establish the proposed generalized model of heat conduction, the Moore-Gibson-Thompson concept was used. As an application to the presented model, a problem of thermally induced behavior in an infinite nonlocal solid with a cylindrical hole whose surrounding surface is free of traction and affected by a time-dependent moving heat supply is studied. In the transformed field of the Laplace transform, analytical formulas for thermophysical fields have been derived. To obtain the numerical results of the physical field, an approximate approach was applied to find the numerical inversion. The effect of non-localization and heat source velocity on the responses of the investigated fields is graphically illustrated and discussed in detail. The results show that Eringen’s non-local elasticity model is a promising criterion for analyzing nanostructures, taking into account the effect of small size.
Recovering a source term in the higher-order pseudo-parabolic equation via cubic spline functions
Authors: Huntul M J 
Published: February 2022

Abstract
In this paper, we considered an inverse problem of recovering the space-dependent source coefficient in the third-order pseudo-parabolic equation from final over-determination condition. This inverse problem appears extensively in the modelling of various phenomena in physics such as the motion of non-Newtonian fluids, thermodynamic processes, filtration in a porous medium, etc. The unique solvability theorem for this inverse problem is supplied. However, since the governing equation is yet ill-posed (very slight errors in the final input may cause relatively significant errors in the output source term), we need to regularize the solution. Therefore, to get a stable solution, a regularized cost function is to be minimized for retrieval of the unknown force term. The third-order pseudo-parabolic problem is discretized using the Cubic B-spline (CB-spline) collocation technique and reshaped as non-linear least-squares optimization of the Tikhonov regularization function. Numerically, this is effectively solved using the lsqnonlin routine from the MATLAB toolbox. Both perturbed data and analytical solutions are inverted. Numerical outcomes are reported and discussed. The computational efficiency of the method is investigated by small values of CPU time. In addition, the von Neumann stability analysis for the proposed numerical approach has also been discussed.
Impact of strain on the electronic, phonon, and optical properties of monolayer transition metal dichalcogenides XTe2 (X = Mo and W)
Authors: Islam Md Rasidul , Mojumder Md Rayid Hasan , Moghal Biazid Kabir , Islam A S M Jannatul , Miah Mohammad Raza , Roy Sourav , Kumar Anuj , Shihavuddin A S M , Ashique Ratil H 
Published: February 2022

Abstract
Here, we provide a systematic assessment of biaxial strain effects on the electronic, phonon, and optical properties of monolayer transition metal dichalcogenides (TMDs) XTe2 (X = Mo and W) using density functional theory calculations. We observed a large direct bandgap of 1.163 eV and 0.974 eV for MoTe2 and WTe2, which reduced to 1.042 eV and 0.824 eV in the spin–orbit coupling ambient. The XTe2 structures show a tunable bandgap with the variation of the applied biaxial strains. Due to the breaking of inversion symmetry, a large spin-valley coupling emerged at the valance band edges for both MoTe2 and WTe2 monolayers under applied biaxial strain. The phonon properties with different biaxial strains reveal that monolayer MoTe2 is more stable than the WTe2 structure. The calculated optical properties demonstrate that the dielectric constant and absorption coefficient of MoTe2 and WTe2 move to higher photon frequencies when the compressive strain is increased. On the other hand, with the increase in tensile strain, a red-shift behavior is found in the calculated optical properties, indicating the suitability of the XTe2 monolayer for different infrared and visible light optical applications.
A ship target dynamic recognition method based on image recognition and VR technology
Authors: Fei Peng , Chu Xiumin , Geng Xiongfei , Luo Jianan 
Published: February 2022

Abstract
Effective identification of ship identity is an important means of water traffic management. Aiming at the technical limitations of AIS, radar and other means, a ship automatic recognition method based on machine learning is proposed, and a water traffic visualization system integrating multi-source recognition technology is realized based on VR technology. The test shows that the method and system can solve the technical problems of ship identification caused by data easy to be tampered with, difficult to distinguish massive targets and large obstacles, and provide an effective method for navigation support in key waters.
Research on Abnormal Event Classification of Expressway Tunnel based on Security Control
Authors: Hu Jiangbi , Zhang Zechao , Cao Qingyun , Qu Shangwen , Wang Ronghua 
Published: February 2022

Abstract
Based on the perspective of tunnel traffic safety operation and control and the human, vehicle, road, and environment system in tunnel operation process, adopting event tree analysis method according to the different influencing factors, generation mechanism and performance characteristics of tunnel abnormal events, this research propose abnormal event classification tree diagram. According to the current abnormal event management and control mechanism in China, the administration departments and disposal facilities associated with different types of abnormal events in expressway tunnel operation are sorted out, which can provide decision-making support for the rapid treatment of abnormal events and realize intelligent control of tunnel.
A Feature Extraction Method for Non-intrusive Load Identification
Authors: Wei Wei , Peng Tao , Ye Li , Feng Xianyu , Jiang Zisong , Yu Heyang 
Published: February 2022

Abstract
When some household appliances are running, the electrical quantities such as active power and reactive power will change slowly for a long time, which will affect the feature extraction of event-based non-intrusive load identification, resulting in low accuracy of load identification results. In view of this situation, a feature extraction method is proposed. Its core idea is that there is a certain law in the change of active power and reactive power in a very short time, and the curve can be fitted to speculate the values of these electrical quantities in the next time, so as to eliminate the influence. Based on this, a feature extraction method applied to non-intrusive load identification is realized. The test results show that this method can effectively improve the accuracy of non-intrusive load identification feature extraction data, and has good application value.
Study on Thermal Runaway Behavior of Lithium Ion Battery under Overcharge Using Numerical Detecting Method
Authors: Gao Ao , Dong Wenhui , Xu fang , Xu Xiangyang , Fan Lei 
Published: February 2022

Abstract
In order to provide support for the early warning model of thermal runaway of lithium-ion battery, the thermal runaway behavior of power lithium battery is studied by analyzing the charging current, voltage and other parameters of lithium-ion power battery under overcharge condition. In addition, the morphological changes of battery before and after thermal runaway are compared. It is found that under the conditions of this study, overcharging for 58 minutes will lead to thermal runaway of full load lithium-ion battery. In the early stage of thermal runaway, the leakage gas in the battery box will continue to increase, which is 1339 ppm in the First Level early warning, 3405 ppm in the Second Level early warning and 8292 ppm in the Third Level early warning.
Optimal operation method of integrated energy system considering thermal inertia
Authors: Wang Yongli , Liu Zhen , Cai Chengcong , Shen Hekun , Chen Xin , Yang Yang 
Published: February 2022

Abstract
This paper proposes a comprehensive energy system operation optimization method considering the thermal inertia of the heating system. Firstly, based on the energy network of the integrated energy system, establish the thermal inertia and heat storage model of the heating pipeline; secondly, the goal is to minimize the total operating cost of the electricity-heat-gas integrated energy system. Considering constraints such as power balance and safe operation of equipment, an integrated energy system operation optimization model based on thermal inertia is established; the results show that the model can better balance scheduling cost and reliability.
Research on Standards for Information Supportive System in District Energy Internet Construction
Authors: Wang Decheng , Li Yan , Zhang Qun , Chen Qian , Feng Mengshuang , He Xiaotong 
Published: February 2022

Abstract
At present, the concept of Energy Internet has attracted great attention around the world, and is generally considered to be an important means to realize carbon neutrality. In terms of the overall structure, the Energy Internet is composed by physical network system, information supportive system, and value creation system. As is known to all, the information supportive system is the nerve center of the Energy Internet. While to establish the information supportive system of the Energy Internet, standards and specifications are in urgent need. Therefore, this paper mainly focuses on standards for information supportive system in the Energy Internet construction. First, the overall structure of the information supportive system is proposed. Then, the functional characteristics of each layer in information supportive system are analyzed respectively. In addition, the existing standards for information supportive system are summarized. Meanwhile, standards that need to be formulated in the future are analyzed as well. Finally, suggestions are given for the formulation of construction of information supportive system in the Energy Internet.
The Auxiliary System of Video Surveillance in Smart Substation
Authors: Liu Yu , Zhang Chao 
Published: February 2022

Abstract
With the continuous development of artificial intelligence technology, the current substation operation and maintenance personnel have more and more urgent needs for the visualization, remoteness and intelligence of the operation and maintenance system. In order to solve the existing problems and present situation, key technologies such as image acquisition, image recognition, and visual display are studied. A smart substation video monitoring auxiliary system was developed. The system is used advanced cameras and acquisition equipment to monitor and detect related electrical equipment such as hard pressure plate switches in the substation in real time. The goal of intelligent inspection is achieved. In the smart substation project, it has achieved good results and has a wide range of application prospects.
Performance analysis of EES-based transcritical carbon dioxide two-stage compression/ejector refrigeration system for shipboard cold chambers
Authors: Li Yang , Yang Dazhang , Zhang Qing , Xie Jing 
Published: February 2022

Abstract
Carbon dioxide (CO2) as a natural refrigerant has a broad application prospect in the refrigeration system of shipboard cold chambers. In this work, a novel transcritical CO2 two-stage compression refrigeration system equipped with a two-phase ejector for shipboard cold chambers is proposed. At the same time, simulation of the two-phase ejector and the system was carried out by Engineering Equation Solver (EES). Additionally, The effects of high pressure stage exhaust pressure, intermediate pressure and evaporating temperature on system performance were also investigated. The results showed that the system COP increased with the evap-orating temperature increased from -35°C to -25°C. The system COP decreased with the increase in exhaust pressure, when the evaporating temperature is maintained at -35°C. The optimal intermediate pressure is 4.75 MPa, when the evaporating temperature is fixed at -35°C.
The research of Dual MOSFET Parallel technology in Servo drive power
Authors: Ping Zengliang , Wu Shaonan , Ma Yuhua 
Published: February 2022

Abstract
With the development of science and technology, the capacity of high-power power electronic conversion equipment is increasing. The growth rate of current carrying capacity of power electronic converter is lower than that of capacity of high-power power electronic converter. Therefore, the parallel technology of power electronic devices is gradually emerging. In this paper, a double MOSFET parallel technology is proposed, and the feasibility of the scheme is verified by simulation. The scheme can be used in the internal control power supply of power electronic conversion equipment such as driver to realize reliable operation without external control power supply.
Dynamic Analysis and Model Predictive Control of Excavator’s Working Device
Authors: Zheng Penglong , Liu Jian , Wu WeiWei 
Published: February 2022

Abstract
Aiming at the development requirements of automation and intelligence of traditional hydraulic excavator, the robot modeling theory is applied to the modeling process of it, and the general forward and inverse kinematics models of excavator working device including the hydraulic drive structure were given. Based on Lagrange equation, the dynamics model of excavator is established, and a trajectory tracking control method is proposed for this model. The tracking effect of model predictive control method on preset trajectory under different working conditions is studied by computer simulation technology. The research results show that the model predictive control can give a more accurate feedforward control force under complex working conditions, realize accurate tracking of the trajectory, and effectively reduce the control delay caused by large inertia working conditions, and has good robustness.
Research about the on-line system for monitoring the geological subsidence of transmission tower based on high-precision positioning of Beidou
Authors: Cui Zhimei , Huang Zhidu , Tan Siyuan 
Published: February 2022

Abstract
This article proposes an innovative method to achieve Beidou high-precision positioning. Then, the online monitoring physical information system of transmission pole tower is constructed with Beidou high precision positioning and inclination measurement information as the data source. The perception layer is Beidou high-precision positioning sensor and inclination measurement sensor, the data transmission layer is the way of combining wireless private network with wired private network, and the application control layer is the data processing center, which presents the results of analyzing sensor data to the user in a visual interface. The system can send an early warning message to the user at the very early stage of the deformation of the transmission pole tower, So that the user can take measures in time.
Optical FBG-T Based Fault Detection Technique for EV Induction Machines
Authors: Cao Wenping , Alalibo Belema P. , Ji Bing , Chen Xiangping , Hu Cungang 
Published: February 2022

Abstract
Electric vehicles (EV) represent a key technology to achieve a low-carbon transportation objective, whist induction motors are one of the promising topologies. The reliability of these machines is crucial to minimize the downtime, cost and unwanted human lives. Although several techniques are utilized in the condition monitoring and fault detection of electrical machines, there is still no single technique that provides an all-round solution to fault detection in these machines and thus hybrid techniques are used widely. This paper presents a novel non-invasive optical fiber technique in condition monitoring of induction machines and in the process detecting inter-turn short circuit faults. Owing to optical fiber’s immunity to magnetic flux, a composite FBG-T sensor formed by bonding a giant magnetostrictive transducer, Terfenol-D, onto a fiber Bragg grating is utilized to sense machines’ stray flux as a signature to determine the internal winding condition of the machines. A tri-axial auto datalogging flux meter was used to obtain the stray magnetic flux and test results obtained via LabView were analyzed in MatLab. Experimental and numerical results agree with each other and how that the FBG-T sensor accurately and reliably detected the short-circuit faults. Bragg shifts observed under short-circuit faults were in 100s of picometre range under various operating frequencies compared to the mid-10s of picometre obtained under healthy machine condition. These provide much promise for future EVs.
Development of SF6 Gas Pressure Prediction Device in Substation
Authors: Lin Xicheng , Wang Hua , Qin Zheng , Zhao Wendong , Li Xiangchong , Yang Xiaojie 
Published: February 2022

Abstract
SF6 equipment has leakage due to various reasons. The longer the equipment operates, the more serious the leakage is. When the equipment gas leaks to the set air replenishment value, the air replenishment alarm signal will be sent. It can be seen from the SF6 gas temperature pressure relationship table that the temperature change has a great impact on the pressure value. Although the equipment popularizes the SF6 density meter or SF6 density relay with temperature compensation, the compensation system needs to achieve temperature compensation through a long time, resulting in the distortion of the pressure value counted by the operation and maintenance personnel. Therefore, the temperature difference between winter and summer is large, and more alarm signals are obtained. At this time, there are great potential safety hazards in air replenishment. This paper introduces in detail a SF6 gas leakage prediction device in substation, which can effectively solve the above problems in substation.
Power output control method of small power photovoltaic grid connected power generation under complex illumination
Authors: Luo Yun , Lu WenLing 
Published: February 2022

Abstract
Due to the irregular change of lighting conditions, there is a large error in the control of photovoltaic grid connected power output. Therefore, this paper proposes proposes a power output control method for low-power photovoltaic grid-connected power generation considering complex illumination. Based on the analysis of the basic characteristics of photovoltaic grid connected power generation, the output characteristics of photovoltaic array under complex lighting conditions are studied. Combined with its variation characteristics, based on fuzzy control strategy, the output of photovoltaic grid connected energy storage system is adjusted by filter control with variable time constant, and economic operation and stable operation are taken as constraints. The test results show that the design method has a high degree of fit between the control of photovoltaic grid connected power output and the actual results, and the error is within a reasonable range, which is obviously due to the two groups of comparison methods.
Cooperative Control Mechanism of Key Objects and Key Nodes in Container Terminals
Authors: Shi Hankun , Wang Xuelin , Zhou Hongmao 
Published: February 2022

Abstract
This research starts from the operation process of the container terminal, constructs a technical route for the analysis of key objects and key nodes, summarizes the specific distribution of key objects and key nodes of the container terminal, and analyzes the process mechanism and interactive information of the container terminal. The cooperative control mechanism of key objects and key nodes creates a certain theoretical framework for the automation and intelligent design of container terminals.