bluuebunny/crossref_metadata_2025 huggingface dataset:
Remote education system for physics labs based on Arduino and javaScript
Authors: Tavera Romero F , Granados Samaniego J , Seguil S , Velázquez Arcos J M , Cid Reborido A
Published: October 2022

In 2020, a pandemic began, which stopped many of the academic activities around the world; in our university the emerging distance education program PEER by its acronym in Spanish, was implemented which allowed continuity to academic activities of the students. Some theoretical courses could be carried out through video meetings without any problem. But for the labs classes that always have required practices, there was no adequate solution, even if these laboratories are essential for engineering careers. Therefore, we took on the task of design and build an educational system using Arduino development platform and light emission and detection components, in which the most common practices carried out in the university facilities could be implemented but now from anywhere without the need for a large investment of money in specialized measurement equipment.
Design and optimization of large-scale single-crystal furnaces asymmetric hooked magnetic fields
Authors: Wu Haohao , Gao Dedong , Wang Shan , Xu Shengzhe , Ma Tengfei , Li Lirong
Published: October 2022

The solar photovoltaic power generation industry and large-scale integrated circuit industry put forward higher requirements for the size and quality of monocrystalline silicon. However, there are some problems in the production of large-diameter and high-quality monocrystalline silicon, such as uneven crucible thermal field and strong melt convection, which affect the quality of monocrystalline silicon. Therefore, by adopting the finite element 2D modeling method, this paper established the asymmetric hook magnetic field model of the 40-inch crucible. Hence the key magnetic field parameters affecting the growth of a single crystal were determined by controlling the melt convection in the crucible. Meanwhile, through finite element static magnetic field simulations, the effect of the magnetic field at the crucible wall was analyzed by adding the upper and lower guide rings of the magnetic shield structure, the magnetic shield structure with intermediate permeability ring, and the coil parameters. In addition, the parameters of the asymmetric hooked magnetic field structure were also optimized based on the simulation data. On the above basis, a numerical simulation analysis of the key parameters of the magnetic field was carried out. The simulation results show that the optimized asymmetric hook magnetic field structure can effectively control the melt convection in the crucible. In addition, the magnetic field strength at the crucible wall can meet the target of restraining convection by a magnetic field. Hence, it provides a certain reference value for the design of a large-scale single crystal furnace magnetic field.
Effects of ball milling on Structure and Electrochemical Properties of Na4MnV(PO4)3
Authors: Tang Ao , Yang Chenguang , Hu Pu
Published: October 2022

Na4MnV(PO4)3 is regarded as a promising candidate as cathode material for Na-ion batteries (SIB) due to its low cost and high energy density. However, it suffers from fast capacity decay upon cycles, hindering its further commercialization. The ball milling technology was adopted in this study to control the particle size of Na4MnV(PO4)3, and the correlation of electrochemical properties was investigated. With increasing ball milling time, particle size was greatly reduced. The material with 20 minutes of ball milling displayed the best cycling stability and rate capability. It delivered a reversible capacity of 77.1 mAh/g at 0.5 C after 80 cycles, much higher than that of pristine Na4MnV(PO4)3. The decreased particle size might be to blame for the enhanced electrochemical performance, which effectively increased the interfacial contact with the electrolyte and greatly reduced the length of Na-ion diffusion in active particles.
Modeling and optimization of the energy system for series hybrid electric fixed-wing VTOL
Authors: Zhu Yingtao , Zhu Bingjie , Zong Jianan , Yang Xixiang
Published: October 2022

In this paper, the fixed-wing vertical take-off and landing (VTOL) aircraft is studied. Based on the typical mission profile, the flight process of fixed-wing VTOL aircraft is divided into rotor mode and fixed-wing mode, and the dynamic models of the two modes are established respectively. The power transmission model of the series hybrid electric system is established, the concept of hybridization for power (Hp
) is introduced, and an optimization method of power allocation based on Hp
is proposed. The optimization method is verified by simulation, and the results show that, compared with the pure electric energy system, the performance of the optimized hybrid energy system is improved obviously.
Preparation of carbon nanofiber supported Co nanoparticles for improving the electrochemical hydrogen storage properties of Co9S8 alloy
Authors: Sun Yan , Liu Ying , Liu Wanqiang , Tong Junhui
Published: October 2022

Co9S8 alloy was synthesized through mechanical ball milling, and cobalt/carbon nanofiber (Co/CNF) was prepared by the electrospinning process. The addition of Co and CNF increased the discharge capacity of Co9S8 to 563.4 mA/g. Furthermore, the composite electrode exhibited superior high-rate discharge capability, corrosion resistance, and other kinetic properties. CNF provides high conductivity and more reaction sites for Co nanoparticles. Co nanoparticles participate in redox reactions and show a catalytic effect. Moreover, the synergistic effect of CNF and Co also promotes the electrochemical hydrogen storage and kinetic performances of Co9S8 alloy.
Combined optimization of electric heater-heat tank aggregation for wind curtailment
Authors: Zhou Xiaohang , Liu Jian , Ding Mozhi , Zhu Huating , Xu Mingqi , Li Qinmiao
Published: October 2022

As the penetration of renewable generation such as wind and solar continues to grow in power systems, system operation calls for curtailment of excess amount of renewable generation. In this regard, an integrated energy system (IES) can be utilized to optimize curtailment. This paper proposes the Electric Heater-Heat Tank Aggregation (EHHTA) as an IES, also an energy coupling device that combines electricity power with heat energy, to deal with redundant wind power curtailment. A combined optimization model was developed in this paper, which incorporates mathematical models of the energy resources. The simulation was carried out based on the practical data in the case study, where the coordinated control of EHHTA and thermal generators from the optimization model was proven to be effective in mitigating wind power curtailment.
Distribution Joint State Estimation with Multiple Snapshots Based on SCADA and AMI Measurements
Authors: Long Cheng , Zhang Hua , Dong Lilan , Guo Ruipeng
Published: October 2022

To adapt to the distribution network unobservable problem from the scarcity of real-time measurements, the distribution system state estimation (DSSE) method based on hybrid measurements of the supervisory control and data acquisition (SCADA) and the advanced metering infrastructure (AMI) is proposed. Firstly, the ratio of energy data from AMI is used to construct pseudo-measurements, which satisfies the observability of DSSE. Secondly, multiple SCADA acquisition snapshots joint state estimation model is constructed by the SCADA measurements and the energy data of AMI with multiple snapshots. In a rectangular coordinate system, the joint state estimation model and the weighted least squares (WLS) method are described in quadratic polynomial form, leading to a quadratic constraint quadratic estimation (QCQE) model. The QCQE model can decouple the modeling and algorithm implementation of state estimation and enhance the efficiency of algorithm implementation significantly. Otherwise, more state estimation mature algorithms can be adopted for the joint state estimation model in quadratic polynomial form. Simulations on the IEEE 33-bus system verify the accuracy and effectiveness of the proposed method.
Solar Radiation Characteristics in Shanghai
Authors: Dong Sihui , Xu Tianya , Chen Minghao
Published: October 2022

Based on the solar radiation and meteorological data of five meteorological stations of Baoshan, Chongming, Minhang, Fengxian, and Songjiang meteorological stations in Shanghai from 1982 to 2021, the suitable climatological formula for calculating solar radiation in the Shanghai area was selected as Qg = Qt (a+bS) by applying the climatological calculation principle of total solar radiation. The empirical coefficients for each month of the equations were fitted using the least squares method based on the total radiation and sunshine percentages for each month of the calendar year at five meteorological stations. The results show that the average total radiation of Shanghai in 1982-2021 is 4688.69 MJ/m2, among which the total radiation is the most in May, the least in January and December, and although the noon solar altitude angle is the largest in June and July, the total radiation is less than in May and August due to the new influence of the rainy season sky shading than in May. Due to the small area of the Shanghai region, the difference in total solar radiation between the five stations for each month is insignificant. In terms of the spatial distribution of total solar radiation, the northeastern and coastal areas of Shanghai have the most, and the Baoshan area has relatively less; the northern part has the most in spring; the coastal area has the most in summer; the spatial distribution of total solar radiation in winter and autumn is similar, both having the least in the northeast.
Computational study of phase interface properties for energy extraction and storage process
Authors: Cui Xincheng , Wan Chunhao , Du Dongxing , Liu Zhiwei , Jia Pengwei
Published: October 2022

The interactions between gas and liquid have an important role in energy extraction and storage. For example, the interfacial tension (IFT) between the two phases has an important effect on developing crude oil in low-permeability reservoirs and compressed air energy storage in aquifers (CAESA). For the mechanism of two-phase fluid interaction in energy extraction and storage, the study of gas-liquid interface properties is carried out in the paper. Firstly, molecular dynamics simulations are used to study the molecular simulation progress of nitrogen and water under different environmental conditions, and the effects of different temperatures and pressures on IFT are studied. The results show that IFT increases with the temperature increase at constant pressure. When the temperature is constant, an increase in the pressure of the system will decrease the surface tension of the system. Then the effect of IFT on the distribution of gas-liquid phases in the pores of low-permeability rocks is studied by digital core technology and simulation methods. The results show that the lower the IFT of gas and liquid is, the better the displacement effect is and the higher the recovery ratio is in the low-permeability rocks. This study analyzes the IFT and influencing factors between the gas-liquid two-phase interface, and it guides the efficient development and utilization of energy extraction and energy storage.
Experimental study on the low-temperature performance of transformer oil with different trace water content
Authors: Peng Qian , Wang Kangkang , Hu Shengnan , Luo Ziqiu , Zhang Jing , Liu Mengna
Published: October 2022

In oil-immersed transformers, the insulation performance of transformer oil is a key factor for the normal operation of transformers. In order to explore the performance of transformer oil under different micro-water content conditions in a low-temperature environment, this paper builds a low-temperature experimental platform with a minimum temperature of -50 °C and selects the commonly used 45# oil as the test oil. Four properties including conductivity and dielectric properties were tested. The research results show that the viscosity of transformer oil increases exponentially with the decrease of temperature, the thermal conductivity first decreases and then increases with the decrease of temperature, the relative dielectric constant increases approximately linearly with the decrease of temperature, and the micro-water content increases. It has little effect on the above three properties; the electrical conductivity and dielectric loss of transformer oil with different micro-water content both increase first and then decrease with the decrease of temperature, and with the increase of micro-water content, the corresponding peak temperature also increased.
Analysis and optimization of operation mode of outlet communication valves for circulating pump in cold season
Authors: Cheng Shibei , Xu Zixin , Wang Lihua
Published: October 2022

The circulating cooling water system of a coastal power plant adopts a unit seawater supply system. Each unit is arranged with three circulating water pumps. The operating mode of the circulating water pump in the cold season is two for operation and one on standby. If a running circulating water pump trips due to a fault, the standby pump will be activated by interlocking; meanwhile, an opening or closing command will be issued to the two outlet communication valves. According to the state of the outlet communication valve, the risks such as overpressure, condenser vacuum, water hammer, and pump reversal are analyzed. In order to reduce the possible risks in the cold season, an optimization scheme is proposed for keeping the outlet communication valves fully open. The feasibility of the optimization scheme in terms of flow distribution and pipe and equipment stability is also analyzed. The outlet communication valve optimization scheme will reduce operational risk and ensure the safe and stable operation of the circulating water system. The optimization scheme provides reference and experience feedback for the follow-up circulating water system design and operation.
Battery storage system plug-and-play information flow implementation technology
Authors: Wang Xiangjin , Zhang Xuesong , Zhou Chen , Tao Yibin
Published: October 2022

In order to solve the problems that may exist in the large-scale application of energy storage, the “plug-and-play” technology is realized through battery storage power plants. The concept of plug-and-play originates from the network, which refers to the ability of the computer system to configure expansion boards and other devices automatically. This paper researches plug-and-play key technologies for battery storage power stations, aiming to overcome the grid-connected bottlenecks after large-scale application of energy storage systems, improve the effectiveness and convenience of the grid-connected operation of energy storage systems, and effectively improve the practicality of energy storage systems level, supporting the company’s energy Internet development strategy. Based on the technical framework of plug-and-play realization of battery storage power stations, this paper will conduct technical research on the realization of information flow. First, based on the IED modeling method and the actual functional requirements of BESS, we select logical nodes with corresponding functions to form logical devices and establish the BESS information model. Then, we express the self-describing characteristics through the SCL configuration file and analyze the configuration process of the configuration description file CID. Finally, the plug-and-play information flow implementation architecture is constructed with the heterogeneous information model mapping and data conversion module as the core part. Our design can realize the real plug-and-play operation of the battery storage power station connected to the regional power grid, thereby promoting the friendly interaction between the regional power grid and the battery storage power station and improving the adaptability of the battery storage power station in different application scenarios.
Modelling and Control of the Solar Energy Storage System Providing Fast Frequency Support
Authors: Zhang Dezheng , Luo Tao , Yan Dawei , Liu Zhongyi , Li Hui , Xuan Wenbo
Published: October 2022

In order to study the effect of the large-scale solar energy system that can provide fast frequency support to the grid, this paper studies the modeling and frequency control strategies of the solar energy system. The paper firstly explains the working mechanism of the solar energy system consisting of photovoltaic cells and supercapacitor, and then sets up a detailed model of the charge/discharge processes of the solar energy system. Based on the detailed model, this paper compares the different frequency control strategies of the solar energy system and proposes a simplified model of the solar energy system for the power system transient stability analysis. The accuracy of the simplified model is validated through the comparison with the full model.
Study on Efficiency of Compressed Air Emergency Power Supply System Based on MATLAB
Authors: Zhang Zhenzhen
Published: October 2022

Taking a new type of emergency power supply system with compressed air as power source and expander as engine as the analysis object, the working process analysis, and energy loss analysis of the system are made. On this basis, the system analysis model was established, and the relationship between the system efficiency and each influencing parameter was obtained through MATLAB simulation calculation of the system. According to the analysis, it was concluded that when the other parameters were certain, system efficiency with the rising of tanks of compressed gas pressure reduced gradually, the volume expansion ratio of the expander first increased and then decreased, and the increase of inlet pressure expander rose. Still, its growth rate decreased gradually with the increase of leakage coefficient and plummeted. Among various parameters that would influence each other, the pressure range of compressed air stored in the air storage tank needed to be determined according to the structural parameters of the expander. In order to achieve the highest energy utilization rate of compressed gas, according to different system parameters, it was necessary to reasonably match the parameters of the gas storage tank and expander through parametric design.
Ranking method of equipment failure risk in shipboard power system
Authors: Mo Ruokun , Shi Weifeng
Published: October 2022

The realization of equipment failure risk ranking in shipboard power systems is of positive significance to the rapid recovery of ship power system faults. To effectively improve the speed and accuracy of ship fault recovery, accident plans are developed according to ranking results for the top n equipment with high risk. A risk ranking method for distribution equipment is proposed, which takes the outage power, failure probability, MTTR (mean time to repair), and equipment priority of distribution equipment as evaluation indexes, and uses the ENTROPY-TOPSIS analysis method. Taking the DDG-1000 destroyer as an example, the ranking of the failure risk of shipboard power distribution equipment is realized. The calculated results are consistent with the theoretical results, which proves the correctness of the proposed method.
Modeling and performance analysis of electro-mechanical systems for ocean thermal-driven buoys
Authors: Zhang Yulong , Zhou Zhengtong , Shi Wenzhuo , Li Shizhen
Published: October 2022

Marine resources exploration and development can’t be separated from the underwater exploration buoy, battery capacity limits the working time and range of the buoy, the use of ocean thermal energy for underwater exploration buoy energy supply can effectively solve the problem of energy supply. The solid-liquid phase change energy storage technology was used to capture ocean thermal energy, and the electro-mechanical system was used to convert ocean thermal energy into electrical energy to realize the self-supply of buoy energy. In this paper, we studied the influence of the system parameters on the system performance by analyzing the working process of the buoy electromechanical system, establishing the mathematical model of the whole system, and combining AMESim/Simulink simulation technology to reveal the law of ocean thermal energy generation. The results show that increasing the volume of the accumulator and reducing the displacement of the hydraulic motor can help to increase the power generation of the generator and choosing a suitable load can help to increase the power generation.
A zonal balanced market clearing method in AC/DC hybrid system considering inter-area electricity exchange
Authors: He Xinyu , Dong Ping , Liu Mingbo , He Ruijin
Published: October 2022

As the intra-provincial spot market matures and the inter-area electricity exchange increases in China, the market clearing method requires some exploration. This paper proposes a zonal balanced market clearing method in hybrid direct current/alternating current (AC/DC) systems considering inter-area electricity exchange. In each area, the independent operator carries out the intra-area market clearing. The operator of high voltage alternating current (HVAC) and high voltage direct current (HVDC) power transmission channels is responsible for safe system operation and the quotation for each area. According to the results of the areas’ market clearing and the transmission lines’ optimal power allocation, the operator updates the quotation until reaching the convergence conditions. The case studies demonstrate the feasibility of the proposed zonal market clearing method.
Study on the Optimal Operation of Indoor Heating Considering the Envelope Structure in the Context of Time-Sharing Tariff
Authors: Wang Deyu , Sun Ping , Huang Haojia , An Yang , Gao Yunfeng
Published: October 2022

In this paper, a mathematical model of building heat transfer calculation is established, and the heat storage capacity of the building envelope model is tested and applied under the background of time-of-use electricity price. The building envelope in the context of time-of-use tariff in the process of simulating the temperature environment is considered, and the optimal solution derived by comparing the optimized operation scheme on a typical load day is adopted. Through the comparison of common schemes, the scheme proposed in this paper can effectively avoid energy waste, save electricity, improve the operation scheme of indoor heating in buildings, and provide theoretical reference for the optimal operation of building energy saving and consumption reduction.
PD control of VTOL aircraft trajectory tracking based on double-loop design
Authors: Wang Wen-lan , Bai Xiong-huai , Zheng Lei
Published: October 2022

In this design, a VTOL aircraft system is used as the controlled object. Aiming at the trajectory tracking problem of its position and attitude output, a trajectory tracking control method based on double closed-loop PD control is adopted to design. The trajectory tracking system of VTOL aircraft is decomposed into a track tracking subsystem and a roll tracking subsystem. At the same time, a double closed-loop PD control structure based on position outer loop and attitude inner loop is constructed, and a PD controller based on feedforward compensation is designed. The pole assignment method is used to set and select PD parameters. The stability of the double closed-loop system is ensured by the engineering method of making the reaction speed of the inner loop greater than that of the outer loop. Then, MATLAB software is used to simulate whether the control system can track the given trajectory. Simulation results show that this method simplifies the design process of the control system and makes certain that VTOL aircraft can track arbitrary trajectory outputs with three state outputs as soon as possible, thus meeting the needs of underactuated VTOL aircraft for arbitrary trajectory tracking.
Prediction of Wind power rolling interval based on VMD-PSR-LSTM-QR
Authors: Li Jianwen , Mei Fei
Published: October 2022

The integration of wind power into the power grid brings great challenges to the safe operation of the power system. Predicting the wind power interval can avoid effectively the randomness and volatility of the integration, and protect the security and stability of the power grid. Considering the non-stationary characteristics of wind power, this paper proposes a new wind power rolling interval prediction method based on VMD-PSR-LSTM-QR. First, wind power is decomposed into several subsequences by variational mode decomposition (VMD). Second, phase space reconstruction (PSR) maps the subsequences to a high-dimensional space and constructs them. Then, long short-term memory (LSTM) networks are used for training different subsequences, and quantile regression (QR) parameters are determined. Finally, the predicted results of each subsequence are reconstructed. This paper uses actual wind power data in China as examples to verify the proposed method, and it is found that the proposed method achieves significantly higher prediction accuracy than traditional methods.
A network attack link detection method based on the knowledge graph
Authors: Chen Shanfeng , Hu Zhao , Yang Yiyue , Fan Suchun
Published: October 2022

Existing network security detection technologies often detect various network security problems separately. There are limitations in these technologies because of the correlation between entity attack detection and attack capital information. To resolve the problem of poor detection performance of existing network attack link detection methods, this paper proposes a network attack link detection method based on the knowledge graph. Specifically, the link knowledge graph is constructed, the embedded calculation of the knowledge graph of the link attack node is established, a knowledge graph audit model of link attack security detection is constructed, and the detection rules of the link attack knowledge graph are established to identify the association between the link network attack entity and the attack asset attribute, and improve the identification and detection of the attack source by associating the knowledge graph. Experimental results show that the proposed method has better link attack association awareness than other methods reported before.
Early fault detection of distribution network based on the ring law of large-dimensional matrix
Authors: Fu Chaoran , Wang Jiayu , He Xudong , Shao Jiawei , Wei Chen , Shi Xin
Published: October 2022

When faults in the distribution network occur, they usually last for a period of time, but if cannot be detected and eliminated in time, the faults can easily expand or even cause systemic collapse. Therefore, early fault detection of distribution grid is very important for ensuring the safe operation of the system. The existing fault diagnosis approaches based on the physical mechanism model have great limitations. This paper presents an early fault detection approach based on large-dimensional matrix ring law. We first construct a spatio-temporal data matrix by using the data from the spatial multi-node of the distribution network. The moving data window method and the ring law are used to track the data behavior, and the mean spectral radius is used to characterize the data behavior. According to the test results of the IEEE standard bus system, our approach is robust to system random fluctuations and measuring errors and can identify abnormal conditions at the earliest stage of failure.
Effect of annealing temperature on supercapacitive behaviour of manganese dioxide (MnO2) thin-film prepared by electrodeposition technique and characterization
Authors: Jadhav Priti N , Sukhatankar K V
Published: October 2022

The purpose of this study is to demonstrate the construction of Manganese Dioxide (MnO2) Thin-Film on a stainless-steel substrate (AISI304) using the electrodeposition process. A thin MnO2 layer Potentiostatically formed by electrodeposition technique from MnSO4.H2O (aqueous manganese sulphate monohydrated) solution was used to investigate the electrodes’ super-capacitive capabilities. The impact of annealing temperature on the electrochemical characteristics of some materials at temperatures ranging from 100°C-500°C was investigated. The surface morphology of annealed material at 100°C, 200°C, 300°C, 400°C, and 500°C was investigated utilizing a SEM (scanning electron microscope). At 200°C, the cyclic Voltammogram is used to investigate the electrochemical characterisation. The highest value of specific capacitance was calculated from this data and was found to be 184.42F g–1 for 10 mV/s. Utilizing galvanostatic discharging and charging techniques, as well as electrochemical impedance spectroscopy, this research investigates the behaviour of super capacitive materials.
Equilibrium molecular dynamics simulation for investigation on the enhancement of thermal conductivity in ethylene glycol-based ZnO nanofluid
Authors: Sarkar Shubhankar , Ghosh Nanda Kumar
Published: October 2022

The thermal conductivity of ethylene-glycol based ZnO nanofluid is computed using Equilibrium Molecular Dynamics Simulations in the Green-Kubo framework, taking into account the impact of nanoparticle volume fraction and nanofluid temperature. Mean square displacement (MSD) of the liquid phase for base fluid and nanofluid is also studied to investigate the thermal conductivity enhancement mechanism.
A Framework Towards Realization of Smart Manufacturing Systems
Authors: Karadgi Sachin
Published: October 2022

Germany’s National Academy of Science and Engineering (acatech) published its proposals for implementing the key initiative Industry 4.0 in 2013, requiring horizontal integration and vertical integration within and across multiple enterprises and end-to-end digital integration across the product lifecycle. Likewise, a smart manufacturing system emphasizes enhancing the capabilities of manufacturing enterprises considering multiple objectives, like resource utilization and productivity, necessitating the realization of the business cycle for supply chain management, product development lifecycle, and production system lifecycle. However, realizing these individual lifecycles and integrating them as part of a smart manufacturing system is not straightforward due to manifold reasons (e.g., difficult to define the interface points necessary to interact with the various systems associated with these lifecycles). The current article elaborates a systematic framework considering these lifecycles to realize a smart manufacturing system. The framework is divided into different layers starting from the process layer at the bottom all the way up to the smart layer at the top. Finally, a use case from the end-to-end additive manufacturing process has been discussed that employs the previously elaborated framework.
A State of Art Review on Grass Fibre Reinforced Polymer Composite
Authors: Kumar Hrithik , Jaiswal Debangshu , Jena Hemalata
Published: October 2022

The environment awareness and cost cutting are the main beginning to think about eco-friendly materials. Of course, natural fibre as reinforcement in polymer matrix is one of the best option due to its biodegradability, recyclability, low cost and high specific strength/stiffness. It motivates the researchers to find new and easily available bio-fibre which may replace with non-biodegradable material and maintain the proper balance for the ecosystem. Now a day’s, researchers search on new plant fibre that facilitate easy and viable extraction that does not mess up the properties of the fibres. There has been an incredible development in polymer matrix composites of various plant fibre. Grass fibre is one of the important plant fibres which occurs in different parts of plants, mainly in the stems and leaves. Present paper studied on different grass fibres and its extraction process. Different surface treatment of grass fibre has been reviewed to extract the knowledge of the adhesion property of the fibre with polymer and its mechanical property. The present paper has also reviewed the mechanical property of the grass fibre composite. The scope of the grass fibre-reinforced composite material in various structural and engineering application are also addressed here.
A review on classification of trains for evaluate the railway network capacity of various speed trains
Authors: Mittal Manoj , Chaturvedi Anand Kishore
Published: October 2022

Railway is a very complicated decision making sector in a realistic way with numbers of constraints. Several thousands of trains are running over thousands of kilometers. The aim of this paper is to measure the rail network capacity by efficient utilization of existing resources of railway network by analytical model. In this model headway is reduced for variable speed trains so that track blocking time and track running time will be reduced. A case study of 14 sections with 5 corridors have analyzed by CIPLEX solver to develop the generic solution for optimizing rail network capacity to solve real problem. These models are useful in planning phase and can evaluate the entire network of railway.
Study on Performance of Ramjet Intake by Changing the Cowl Angle
Authors: Levi Reuben VR , Rajamani Amrutha
Published: October 2022

Most gas turbine engines require the Mach range on the engine face to be at a mild subsonic pace (around Mach 04). Therefore, for a supersonic plane with a gas turbine engine, the characteristic of the air inlet is to slow the supersonic unfastened flow to a subsonic pace and offer a matched air mass float charge to the engine. The gas turbine engine calls for the delivery of uniform excessive general stress restoration air for proper overall performance and operation because the quality of the airflow on the engine face substantially influences the overall performance of the engine, in particular, the total stress loss, which influences the engine thrust and therefore the gasoline consumption. A 2-D supersonic intake is designed for Mach No. 2.4 at an altitude of 11,000 m. The design of the mixed compression supersonic intake is done numerically, and the design with the k- turbulent module is done using CFD. Optimization of the intake is done by changing the cowl deflection in order to get maximum total pressure recovery. Results are compared to knowing the optimal design. The main advantage of mixed compression is that it gives the maximum total pressure recovery at any Mach number. The computation is done with the ANSYS software.
Analog Performance Analysis of a Novel 5nm Stacked Oxide Top Bottom Gated Junctionless FinFET
Authors: Gangwani L , Hajela S
Published: October 2022

This paper depicts the analog investigation of a Novel Stacked Oxide Top Bottom Gated Junctionless (TBG-JL) Fin-shaped Field Effect Transistor (FinFET) structure. The structure is designed in this way to enhance the switching performance and curtail the Short Channel Effects (SCEs). The study is done on Silvaco Atlas TCAD tools for the Novel Stacked Oxide FinFET device and analyzed against Top-Bottom Gated Junctionless FinFET and Traditional FinFET. The Novel device shows 280 times improvement in switching ratio when stacked against the Traditional JL FinFET at identical gate length at room temperature (300K). The results from device simulation affirm that the Novel device has better analog performance over Traditional Junctionless FinFET and diminishes the Short Channel Effects (SCEs) a cut above the Traditional Junctionless FinFET.
Dual Threshold Voltage Pseudo Domino Logic - Based Buffer with Reduced Power
Authors: Verma K A , Kumar M , Deo M
Published: October 2022

In this paper, a new technique of power reduction in pseudo domino logic-based buffer is proposed with dual threshold voltage. The proposed method employs the dual threshold voltage technique to reduce the power. During the precharge stage, we have used the high threshold voltage transistor in the non-critical path of the circuit, to reduce the leakage current due to which the average power dissipation is minimized. In critical path, low threshold voltage transistors are used. The low threshold voltage transistors are used in evaluation stage, for the performance enhancement of the circuit. Keeper circuit is used with two PMOS transistor which helps in maintaining voltage of dynamic node and improves the noise immunity and speed of the circuit. Also, a NMOS transistor, which is operated by the dynamic node is used which minimizes the leakage by creating a stacking impact. In addition, the clock inverter is enabled via low voltage NMOS which significantly reduces the current in the inverter due to direct connection between the supply voltage (Vdd) to ground.
A Critical Review on the application of coal Bottom Ash inconcrete: An Indian Prospective
Authors: Kiruthiga P. , dave Niragi , Guduru Ramesh
Published: October 2022

Coal Bottom Ash (CBA) is one of the by-products of Coal sourced Thermal Power Plants. Unlike Fly ash most of the CBA are dumped as landfills rather than utilized. Replacement of CBA in concrete reduces the burden on waste management and reduces the demand for the river sand and Portland cement. The main and major composition of CBA is Silica hence it has pozzolanic properties. The utilization of CBA in concrete is done by adopting several treatment and process in order to its effective replacement as sand and cement. The process involved in the replacement of cement is Grinding or Pulverization. Pulverization increases the Surface area and fineness of CBA and is comparable with the cement hence pulverized CBA can be used as a cement replacement. Whereas sieving is done to replace as a sand. The focus of this study is to prove that CBA can be used in concrete without any significant loss in the strength, durability properties and the optimum dosage of CBA to improve the performance of the concrete. This review compares the results of several researches on mechanical and durability properties and determine the areas where the research has to be carried out further.
Effect of temperature on structural, optical, and morphological properties of ED-CdTe thin film
Authors: verma Lekha , khare Ayush
Published: October 2022

On fluorine-doped tin oxide (FTO) coated glass substrates, CdTe thin films were electrodeposited (ED) using an aqueous electrolyte bath solution. The temperature value of the electrolyte solution is one of the most important deposition parameters that should be adjusted to produce good quality photoconductive material. In our study, the films have been deposited at a different temperatures ranging from 50 to 70°C. Structural properties of the CdTe thin films were characterized using X-ray diffraction (XRD), and using UV–Visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) techniques, and the optical and morphological properties were studied. The cubic crystalline structure of the ED-CdTe films is confirmed by the XRD analysis, and as the temperature is changed, the diffraction peak intensity significantly increased. In optical absorption spectra, the direct energy band-gap (Eg=1.48eV) is obtained. By adjusting the temperatures, the SEM analysis proves very good morphological growth, and the EDX study confirmed the atomic composition of the CdTe layers.
Screen printed ZnO thick films for NH3gas sensing
Authors: Salunke Vaishali T. , Buchade P.B. , Shaligram A.D. , Borse R.Y.
Published: October 2022

The paper reports the synthesis of ZnO powder by self-propagation solution combustion method and the development of screen-printed ZnO thick films for sensing ammonia gas. The surface and structural examination of the thick film was studied by using SEM and XRD techniques. The particle and grain size of the thick film were determined using SEM and XRD respectively. The temperature coefficient of resistance (TCR), electrical, and NH3gas sensing characteristics of ZnO thick film were observed with varying temperatures. Thick films show the inverse relations of resistance with respective temperatures. The sensitivity, response, and recovery time toward NH3 gas sensing were discussed.
Natural radioactivity assessment of surface soil collected from Poovar village of Kerala, India
Authors: Soniya S R , Jojo P J
Published: October 2022

Making use of gamma ray spectrometric analysis method, the activities of soil-borne radio-nuclides viz. 226Ra, 232Th and 40K in the surface soil samples from a specific village in coastal county has been determined. The surface soil of living environment in the Poovar village was used for the study. The activity concentration is used for evaluating various radiologically vital parameters such as levels of radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), absorbed gamma dose rate (D), outdoor and indoor annual effective dose (AED), representative gamma radioactivity level index (Iγ) and alpha index (Iα) in the region. The estimated radioactivity concentrations of 226Ra, 232Th and 40K was observed to fluctuate from below detectable level (BDL) of the instrument to 9 Bqkg−1, 21 Bqkg−1 to 36 Bqkg−1 and 453 Bqkg−1 to 585 Bqkg−1, respectively. Since all of the samples investigated in the study are within the advised limit, there are no radiation threats to the human beings in the region. The obtained information in this research can be used for future radiological mapping and impact assessments.
Novel cryo-tomography workflow reveals nanometer-scale responses of epithelial cells to matrix stiffness and dimensionality
Authors: Gaietta Guido , Kai Fuiboon , Swift Mark F. , Weaver Valerie M. , Volkmann Niels , Hanein Dorit
Published: October 2022

A novel workflow combines tunable extracellular-matrix models with cryogenic electron tomography, two methods previously incompatible, which allows nanometer-scale imaging of intact cells. The workflow allows quantifying nanometer-scale structural changes in response to changes in matrix parameters such as those occurring during cancer progression.
Rap1 regulates apical contractility to allow embryonic morphogenesis without tissue disruption and acts in part via Canoe-independent mechanisms
Authors: Perez-Vale Kia Z. , Yow Kristi D. , Gurley Noah J. , Greene Melissa , Peifer Mark
Published: October 2022

Embryonic morphogenesis is powered by dramatic changes in cell shape and arrangement, driven by the cytoskeleton connected to adherens junctions. The role of the small GTPase Rap1 and its GEF Dizzy is explored, using Drosophila as a model. Rap1 regulates apical contractility and epithelial integrity, using Canoe and additional effectors.
Plastic response of leaf traits to N deficiency in field-grown maize
Authors: Fan Panpan , Ming Bo , Anten Niels P R , Evers Jochem B , Li Yaoyao , Li Shaokun , Xie Ruizhi
Published: October 2022

Nitrogen (N) utilization for crop production under N deficiency conditions is subject to a trade-off between maintaining specific leaf N content (SLN) important for radiation-use efficiency versus maintaining leaf area (LA) development, important for light capture. This paper aims to explore how maize deals with this trade-off through responses in SLN, LA and their underlying traits during the vegetative and reproductive growth stages. In a 10-year N fertilization trial in Jilin province, Northeast China, three N fertilizer levels have been maintained: N deficiency (N0), low N supply (N1) and high N supply (N2). We analysed data from years 8 and 10 of this experiment for two common hybrids. Under N deficiency, maize plants maintained LA and decreased SLN during vegetative stages, while both LA and SLN decreased comparably during reproductive stages. Canopy SLA (specific leaf area, cm2 g–1) decreased sharply during vegetative stages and slightly during reproductive stages, mainly because senesced leaves in the lower canopy had a higher SLA. In the vegetative stage, maize maintained LA at low N by maintaining leaf biomass (albeit hence having N content/mass) and slightly increasing SLA. These responses to N deficiency were stronger in maize hybrid XY335 than in ZD958. We conclude that the main strategy of maize to cope with low N is to maintain LA, mainly by increasing SLA throughout the plant but only during the vegetative growth phase.
An online framework for survival analysis: reframing Cox proportional hazards model for large data sets and neural networks
Authors: Tarkhan Aliasghar , Simon Noah
Published: October 2022

In many biomedical applications, outcome is measured as a “time-to-event” (e.g., disease progression or death). To assess the connection between features of a patient and this outcome, it is common to assume a proportional hazards model and fit a proportional hazards regression (or Cox regression). To fit this model, a log-concave objective function known as the “partial likelihood” is maximized. For moderate-sized data sets, an efficient Newton–Raphson algorithm that leverages the structure of the objective function can be employed. However, in large data sets this approach has two issues: (i) The computational tricks that leverage structure can also lead to computational instability; (ii) The objective function does not naturally decouple: Thus, if the data set does not fit in memory, the model can be computationally expensive to fit. This additionally means that the objective is not directly amenable to stochastic gradient-based optimization methods. To overcome these issues, we propose a simple, new framing of proportional hazards regression: This results in an objective function that is amenable to stochastic gradient descent. We show that this simple modification allows us to efficiently fit survival models with very large data sets. This also facilitates training complex, for example, neural-network-based, models with survival data.
Multimodal neuroimaging in post-COVID syndrome and correlation with cognition
Authors: Díez-Cirarda María , Yus Miguel , Gómez-Ruiz Natividad , Polidura Carmen , Gil-Martínez Lidia , Delgado-Alonso Cristina , Jorquera Manuela , Gómez-Pinedo Ulises , Matias-Guiu Jorge , Arrazola Juan , Matias-Guiu Jordi A
Published: October 2022

Brain changes have been reported in the first weeks after SARS-CoV-2 infection. However, limited literature exists about brain alterations in post-COVID syndrome, a condition increasingly associated with cognitive impairment. The present study aimed to evaluate brain functional and structural alterations in patients with post-COVID syndrome, and assess whether these brain alterations were related to cognitive dysfunction. Eighty-six patients with post-COVID syndrome and 36 healthy controls were recruited and underwent neuroimaging acquisition and a comprehensive neuropsychological assessment. Cognitive and neuroimaging examinations were performed 11 months after the first symptoms of SARS-CoV-2. Whole-brain functional connectivity analysis was performed. Voxel-based morphometry was performed to evaluate grey matter volume, and diffusion tensor imaging was carried out to analyse white-matter alterations. Correlations between cognition and brain changes were conducted and Bonferroni corrected. Post-COVID syndrome patients presented with functional connectivity changes, characterized by hypoconnectivity between left and right parahippocampal areas, and between bilateral orbitofrontal and cerebellar areas compared to controls. These alterations were accompanied by reduced grey matter volume in cortical, limbic and cerebellar areas, and alterations in white matter axial and mean diffusivity. Grey matter volume loss showed significant associations with cognitive dysfunction. These cognitive and brain alterations were more pronounced in hospitalized patients compared to non-hospitalized patients. No associations with vaccination status were found. The present study shows persistent structural and functional brain abnormalities 11 months after the acute infection. These changes are associated with cognitive dysfunction and contribute to a better understanding of the pathophysiology of the post-COVID syndrome.