bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis Of The Flow Pulsation Characteristics Of The Gear Pump Used in Electro-Hydrostatic Actuator
Authors: Tian Yan-quan , Zhang Yu-qiang , Han Xu , Wang Yuan-yin
Published: March 2023

Linear conjugate internal gear pump has low noise and a smooth flow, but the mechanism of flow pulsation, especially the experiment, is seldom studied. In this paper, the flow rate formula of instantaneous, flow pulsation rate and relative volume change of the trapped oil cavity are derived by means of theoretical calculation. The pressure fluctuation characteristics of the trapped oil chamber and flow pulsation characteristics of the pump outlet are studied by using the three-dimensional fluid dynamics finite element simulation analysis method. According to the international standard of ISO10767-1-2015, the pump outlet flow pulsation test was conducted. The flow pulsation rate of a certain type of linear conjugate internal gear pump with a displacement of 10mL/r is about 6.35% under the condition of the speed of 750r/min and outlet pressure of 7.5MPa, and the flow pulsation is small.
Influence of Single External Store on Geometrical Nonlinear Flutter of High-aspect-ratio Wings
Authors: Yu Lingfu , Yu Chunjin , Zhou Quanzhi
Published: March 2023

High-altitude and long-endurance UAVs, distributed electric propulsion aircraft and large passenger aircraft often use high-aspect-ratio wings, which have obvious geometric nonlinear large deformation effect, and are usually arranged with a certain number of external stores, which have an impact on their geometric nonlinear aeroelastic characteristics. Based on the “quasi-linear” hypothesis, the updated Lagrange incremental finite element method and doublet-lattice method are used to perform the geometrically nonlinear static aeroelastic analysis, and the mass, stiffness and aerodynamic matrices of large deformation are updated, and the geometrically nonlinear flutter characteristics of high-aspect-ratio wings are calculated. The influence of the position and mass of the external store on geometrical nonlinear flutter characteristics of high-aspect-ratio wing structure is investigated. Results show that the change of the position and mass of the external store causes the relative position between the elastic axis and the center of gravity of the wing, and the wing’s large deformation equilibrium state to change, resulting in differences in the stiffness characteristics of the wing and the natural vibration frequency of the equilibrium state, thus affecting the wing flutter characteristics. When a single external store is installed near the wing root, changing the mass and direction of the store has no significant effect on the geometric nonlinear flutter characteristics of the wing. The improvement of wing flutter speed is most obvious when the hanging point is moved to the leading edge of the wing near 0.65 times the wingspan.
Durability Analysis of Wind Turbine Blade Coating under Random Aeolian Sand
Authors: Liu Guangyou
Published: March 2023

Wind turbine has a poor working environment and suffered from Aeolian sand and rain for a long time, which results in serious damage to blade coating and greatly affects the later maintenance, the safe and stable operation of wind turbine. In this regard, this paper intends to use numerical simulation method to simulate the erosion process of blade coating under random Aeolian sand, and then study its durability in Aeolian environment. Taking Inner Mongolia as an example, the Weibull distribution wind speed model is established by using the measured wind speed data, and then the dynamic pressure, the impact load and the stress response of blade coating are obtained by FSI (Fluid Structure Interaction) analysis, finally, the fatigue life of blade coating is analyzed by nCode (nCode software). The results show that the dynamic pressure, the impact load and the stress response of blade coating is between20-140 Pa, 0.4-7.9 N and 0.4-2.79 MPa respectively. The maximum damage of blade coating is located near the leading edge of blade tip and its side, and the fatigue life of blade coating is 2.0×108 s.
Analysis of Micro-Electric Vehicle with Super Capacitor/Battery Hybrid Energy Storage System
Authors: Qi Jiyan , Su Ming
Published: March 2023

For the self-developed micro-electric vehicle (MEV), the supercapacitor/battery hybrid energy storage system (HESS) parameters were matched by analyzing the vehicle dynamic and economic constraints. The power distribution of HESS was realized by the fuzzy control strategy, and the entire vehicle model was also built to simulate the dynamic performance. The LCC model of MEV was established based on the comprehensive research of the life cycle cost (LCC). Quantitative comparisons and simulation results show that the micro electric vehicle with supercapacitor/battery HESS has great advantages in dynamic and economy. In the future, with the maturity and popularization of related technologies, the supercapacitor/battery HESS will have a huge preponderance.
Launch Dynamics Analysis of a Grenade Machine Gun with High Muzzle Velocity Based on the Soft Recoil Technology
Authors: Song Jie , Si Peng , Liao Zhenqiang , Qiu Ming
Published: March 2023

To study the dynamic performance of a grenade machine gun system with soft recoil technology and analyze the floating mechanism parameters affecting the firing dispersion, a rigid-flexible coupling multi-body dynamics model was established. A twenty-round firing process of the grenade machine gun system was simulated and analyzed. The firing dispersion of the grenade machine gun system was obtained based on the external ballistics model, and the simulation model was validated by comparing the numerical results with the experimental data. The effects of the floating mechanism parameters on the cradle force, the projectile dispersion, and the firing dispersion sparsity were discussed. The results show that the projectile dispersion of the GMG system is well predicted by the simulation model, and the floating parameters that are matched reasonably could improve the firing dispersion and reduce the gun recoil force.
Thermal Elastohydrodynamic Lubrication Analysis for Rolling Cone Enveloping End Face Worm Drive
Authors: Huang Geng , Liu Huan
Published: March 2023

To explore the thermal elastohydrodynamic lubrication performance of rolling cone enveloping end face worm drive, the mathematical model of thermal elastohydrodynamic lubrication is established based on the meshing theory of rolling cone enveloping end face worm drive and elastohydrodynamic lubrication theory. With the help of the numerical analysis software MATLAB, the thermal elastohydrodynamic lubrication performance under smooth conditions is selectively analyzed by the multigrid method. Besides, the effects of throat coefficient, cone apex radius and half cone angle of the rolling cone on thermal elastohydrodynamic lubrication performance are analyzed at the meshing out of the transmission pair. The results show that the thermal elastohydrodynamic lubrication film thickness at meshing out of the worm gear is the smallest; the oil film thickness, oil film pressure and oil film temperature are reduced from meshing in to meshing out. The oil film temperature at the interlayer is the largest. The oil film temperature at the end face worm surface is the smallest. The small half-cone angle of the cone apex radius and larger throat coefficient and cone apex radius may achieve better thermal elastohydrodynamic lubrication performance of rolling cone enveloping end face worm drive.
Study on the Influence of Process Parameters on Machining Force in Turning ADI by Response Surface Methodology
Authors: Zhao Lidong , Li Baodong
Published: March 2023

ADI (austempered ductile iron) has the unique advantages of high toughness and wear resistance, but it is a kind of difficult-to-machine material because of the larger machining force and high machining temperature in machining. In this paper, the influence of process parameters on the machining force is studied by turning test, and the quadratic response surface regression model of machining force is established. The results show that the primary machining force (Fx
) decreases when cutting-speed v increases, which is due to the softening of the cutting layer of the ADI when feed-rate f increases, and the strength and hardness decrease accordingly. When the feed-rate f and cutting-depth a
p increase, the Fx
increases rapidly, because the contact area of the cutter and workpiece in the effective cutting area becomes larger, and then the deformation and friction increase, leading to rapid increase of the Fx
.
Design and Implementation of Automatic Switching Exhaust Method and Air Intake Method Bell Prover Gas Calibration Facility
Authors: YongWan  , PengTian
Published: March 2023

As the classical bell prover gas calibration facility has the feature that is exhaust method or air intake method alone, in this paper, a new automatic bell prover gas calibration facility that combines the exhaust method and air intake method is designed. Firstly, the flowmeter, pipelines, and other related pipe fittings are mounted in advance. Then, through the system software, control on-off valves condition to switch different pipelines direction and select expected items. Lastly, the system collects the experimental dates to realize the exhaust method and air intake method altogether automatically. The newly designed facility doesn’t need to change lines manually which is time-consuming and laborious, and the calibration results are accurate and reliable as well. At the same time, the new facility which can be reconstructed from the original facility has a compact structure and small occupancy space, and it is easy to implement and has good practical and promotional value.
Optimal Design of Orthogonal Test for Resistance Spot Welding
Authors: Yuan Bo , Liu Yan , Zhang Wenqi , Tian Zhen , Zhao Shan , Feng Wenxiong
Published: March 2023

The optimal parameters of the resistance spot welding process are discussed, combined with the development and practice of the automobile manufacturing industry. The value, significance, and basic theory of the resistance spot welding process orthogonal test are summarized, and the importance of the orthogonal test is recognized. Then summarize the orthogonal test specimen and equipment preparation, test design, and finally analyze the orthogonal test to conclude that the optimal parameters of the resistance spot welding process are optimized, that is, the welding time is 9cyc, the electrode pressure is 1600N, and the optimal welding current is It is 11.5kA, which provides a reference for future manufacturing.
Study on the composition of a four-dimensional track display platform for aircraft based on an open-source GIS platform
Authors: Zhao Haifeng , Hou Yan , Zheng Ruikang , Zhang Jiarui
Published: March 2023

As one of the cores of the new-generation civil aviation transportation system, China’s new-generation air traffic management system (CNGATM) includes various contents, such as track-based operation (TBO), which has attracted more and more scholars’ attention. Traffic management for all these periods is based on the aircraft’s four-dimensional (4D) trajectory. Based on the BADA database, this paper establishes a track simulation model, obtains the flight track through simulation experiments, and analyzes the characteristics of the track. Combined with the flight dynamics model, through the study of the four-dimensional (4D) trajectory of the aircraft, the uncertainty of the aircraft path is significantly reduced, and the utilization and safety of airspace and airport resources are improved.
Steering knuckle lightweight research for additive manufacturing
Authors: Liu Lirong , Li Jinzhe , Tian Chunlin
Published: March 2023

As an important part of the automotive suspension system, the quality of the steering knuckle directly affects the power and safety of the whole vehicle. The lightweight of the steering knuckle is an important way to reduce the weight of the car. This paper focused on the steering knuckle of a car. Firstly, the maximum knuckle model was built according to the place of the joints (hard points). Then, the knuckle’s force in extreme conditions was analyzed by finite element methods. The result was used as the optimization boundary condition to topology optimize the part and we can get the optimized model. Finally, the model was rebuilt and analyzed again. The analysis results verify that the new structure of steering knuckles is rational.
Application of fractional controller in longitudinal control of aircraft
Authors: Liang Renjie , Liu Panling , Liu Miao
Published: March 2023

With the continuous development of many engineering applications, sometimes, integer order controllers can not meet the requirements of the index. Because of the progress of computer simulation and mathematical theory, fractional control theory comes into being. Given the fractional control theory, this paper first introduces the fractional controller’s theoretical basis and description form and then proposes a fractional controller. The reinforcement of the fractional controller is analyzed in the frequency domain direction, and the fractional controller is applied to the pitch angle control of the aircraft pitch channel. The simulation results show that in the pitch angle control on the longitudinal channel of the aircraft, the proposed controller in the longitudinal control loop makes the aircraft’s pitch angle control significantly improved in control accuracy, dynamic process, and steady process compared with the traditional controller.
Research on the Calibration Method of Laser Arch Measuring Instrument
Authors: Cheng Pengli
Published: March 2023

In view of the inconvenience caused by the lack of relevant calibration methods for the laser arch measuring instrument, this paper obtains the main components of the error based on the analysis of the principle of the arch measuring instrument, proposes the calibration methods for each error, and carries out experimental verification. The results show that the error is mainly angle error and distance error. The influence of angle error on the results decreases with the increase of the angle. According to the influence of ranging error and angle error in practical use, the methods of measuring the ranging error of the arch measuring instrument with a standard steel tape and measuring its vertical error and angle error with a movable vertical lifting two-dimensional platform are designed. The experimental results show that the calibration method is feasible.
Research and Exploration of Terahertz Feeder Manufacturing Technology Based on Micro-precision Machining
Authors: Wang Renche , Lv Hui , Zhai Jiamin , Shen Tao
Published: March 2023

With the development of radar towards high frequency, the demand for terahertz waveguides and other devices is gradually increasing. But it is difficult to prepare such high-precision micro-devices by conventional processing methods. This paper summarizes several micromachining methods commonly used in terahertz feeder devices. On this basis, according to the development requirements of a certain type of terahertz waveguide with the characteristic of single-input-four-output, an experimental exploration is carried out. In the development process, the methods of precision NC machining and micro electroforming are comprehensively applied. which breaks through the difficulties of reliable transfer of surface coating and efficient dissolution of micro mold. The sample that meets dimensional accuracy and microwave performance was successfully prepared. The scheme has a reasonable process setting and can promote the engineering application of terahertz waveguide devices.
Agile Micro-nano Satellite Attitude Estimation with Lost Measurements
Authors: Chen Yajing , Meng Tao , Jin Zhonghe
Published: March 2023

Aiming at the problem of lost measurement in attitude determination process of the agile micro-nano satellite, a novel algorithm is proposed employing the Bernoulli process to describe the loss process. Firstly,the model of gyro and star sensors as well as the satellite attitude estimation system simplified with gyro is given. Since the missing observations, the modified EKF algorithm is derived by combining a Bernoulli random variable and a real-time measurement noise correction algorithm. Then the convergence of the improved algorihtm is analyzed, and the bottom boundary condition for the observation arrival rate is presented. Finally, the improved method is compared with the conventional one through digital simulation, and the experimental results show that the preciseness of the privious one is one or two orders improved compared with the latter.
Research on TTT Curve of Alloy structural Steel based on Machine Learning
Authors: Gao Zhiyu , Fan Xianjin , Xia Tian , Xue Weihua , Gao Sida
Published: March 2023

Austenite isothermal transformation curve (IT) of steel, also known as time-temperature-transformation curve (TTT) is an very important basic data for the heat treatment process design of steel. Traditionally, obtaining TTT information on metal mainly depends on experiments, so there are problems such as data dispersion, large errors, and inconvenient access in use. Using artificial intelligence and machine learning technology, the TTT curve of steel can be predicted with limited experimental data. Taking the authoritative data collected as training samples, the TTT curve of alloy structural steel was predicted based on a variety of machine learning algorithms.. Alloying element category, austenitizing temperature, phase transformation time are taken as input characteristics, and 10 kinds of transformation characteristics are taken as output targets. Correlation coefficient (R), and error analysis (RMSE, MAE) are used to evaluate and finalize the model, and the best algorithm is selected to form a combined-machine-learning algorithm (CML), and predict the TTT curve. Take the application of CML multi-model prediction method in 40Cr, 38CrMoAl, 35SiMn, and 20Mn2, and the predicted results reflect that the CML model has high prediction ability and good generalization.
Research on Mechanical Properties of Winding Axial Bending Under Unbalance of Transformer Pad
Authors: Zhu Linghui , Wang Ping , Gao Shuguo , Geng Jianghai , Tian Yuan
Published: March 2023

To improve the study on the influence of transformer windings and pad support on transformer short-circuit resistance, the calculation method of wire bending elastic modulus is analyzed, and the sample test is carried out: The influences of the unbalance of the two ends of the wire between the number of wires wound and the span of adjacent pads on the force-deflection curve, the bending force at the selected deflection, and the elastic modulus of bending were analyzed. The results showed that: Increasing the number of wires and decreasing the height difference of adjacent pads can improve the bending force and bending elastic modulus of wires, the axial stability, and short-circuit resistance of transformer windings. When the height of the adjacent pad is not balanced, the axial force can increase the compression degree between the pad and the wire, and reduce the span of the wire. Under the action of force, the wire yields twice, which further reduces the bending force and elastic modulus of the wire. This research can provide test data support for improving the installation of transformer winding pads and theoretical evaluation of short-circuit tolerance.
Voltage Sag Recognition Based on CM-eCNN Model For Few-Shot Learning
Authors: Peng X F
Published: March 2023

Voltage sag is a serious problem in power systems. To reduce voltage sag, it is necessary to identify and classify voltage sag sources. However, due to insufficient voltage sag data, our paper designs a CM-eCNN model through few-shot learning. Firstly, this paper introduces the CM-eCNN model and studies how to improve the extraction efficiency of the constellation model to feature map through the attention mechanism. Then, it introduces the training method of few-shot learning. Finally, our model training with few-shot learning has better performance than other models, which proves effectiveness of the model.
Construction and Simulation Analysis of A New Transformer Noise Prediction Model
Authors: Han Xue , Chen Tengfei , Yang Guang , Li Huiqi , Song Wenle , Wang Lei
Published: March 2023

In recent years, more and more attention has been paid to the environmental impact of substation operation noise. Therefore, a suitable noise prediction model is needed to evaluate the noise impact. The noise in the substation mainly comes from the main transformer. The predictions of the main transformer noise model in the existing technical specifications often do not correspond to the actual situation. Therefore, based on the theory of planar Nearfield Acoustical Holography (NAH) equivalent source approach, a new transformer noise prediction model called the main transformer noise model of the directional dot-matrix equivalent source is established. Using this model, a typical 500 kV substation is simulated in Cadna/A, and the results are compared with the simulation values and measured data of the existing standard main trans-former noise model. The comparison shows that the new prediction model can accurately predict the noise value of the substation, and the error is less than 2 dB(A).
Research on Transformer Fault Diagnosis Model Based on Improved GOA-SVM
Authors: Li Wannian , Xiao Jinfeng
Published: March 2023

A transformer fault diagnosis model based on the improved grasshopper optimization algorithm-optimized support vector machine (SVM) is proposed to improve the precision of transformer fault diagnosis and avoid the issues that the traditional grasshopper optimization algorithm (GOA) is prone to falling into local optimal solution and slow convergence. Firstly, the grasshopper population is initialized using the elite backward learning strategy to improve the initial population quality and search efficiency. Then, the Sigmoid function is introduced to improve the linear weight decreasing of the grasshopper algorithm into nonlinear weight decreasing to strike a balance between the algorithm’s capacity for both local and global exploration. Finally, the kernel function parameters and penalty coefficients of the SVM are optimized with the improved grasshopper optimization algorithm (IGOA) to establish a model based on dissolved gas analysis (DGA) in oil-based IGOA algorithm-optimized SVM for transformer fault diagnosis model and verify the effectiveness and superiority of IGOA-SVM to identify transformer fault states by comparing with PSO-SVM and GOA-SVM.
Multi-level Topology and Dynamic Power Sharing of Household DC Distribution System
Authors: Han Jun , Xie Zhenjian , Cai Chao
Published: March 2023

With the popularity of electronic information products and the gradual adoption of DC speed control in electric household appliances, more and more household appliances are equipped with rectifiers or inverters. Moreover, household rooftop PV, wind turbines and energy storage devices also output electric energy in the form of DC. This paper presents a topology of household DC distribution system, which not only improves the reliability of power supply from the power consumption mode, reduces the loss in the process of power form conversion, but also provides users with safer voltage level and more reasonable fault protection. On this basis, this paper proposes an instantaneous power sharing scheme based on droop control, which enables each power module of the system to achieve steady-state and dynamic power sharing.
Calculation Method of Hosting Capacity for Distributed Grid-connected Photovoltaic Based on IGWO
Authors: Xie Jicheng , Tang Yi
Published: March 2023

In recent years, the distribution grid has been taking more and more risks due to the large-scale access of distributed photovoltaics (DPV), including potential problems such as voltage overrun and tidal current reversal, which seriously threaten grid security. Therefore, studying the maximum access capacity of distributed photovoltaics in the distribution grid is a research need nowadays. In this paper, we first establish a distributed PV grid-connected optimization operation model for distribution networks, taking into account multi-dimensional constraints such as voltage, load capacity, and active power, and then propose a grey wolf optimization based on particle swarm and Bernoulli chaos mapping, using chaos mapping initialization population, nonlinear convergence factor, and position update idea in the particle swarm algorithm to increase the initial population diversity and solution accuracy. Then, we use the improved grey wolf optimization algorithm (IGWO) as the basis for solving the maximum access capacity of distributed PV for distribution networks. Finally, simulations are conducted on the IEEE-33 node system to exemplify the previously developed model and algorithm.
Two-layer Optimization of Energy Efficiency Based on Provincial Smart Energy Service Platform
Authors: Cheng Baohua , Zhang Hualu , Deng Boya , Shi Jie , Zhou Xiaofei , Su Huiling , Ren Yucheng , Ji Ruilin
Published: March 2023

The study relies on the provincial smart energy service platform of Jiangsu Province, optimizes its accurate prediction module of energy consumption and the energy efficiency improvement module, and proposes an efficiency improvement strategy based on the two modules of the platform. The accurate prediction module adopts the data processing and feature analysis method based on STL-MIC and builds a deep learning framework based on CNN-BiLSTM. The projected predicted data is then input to the energy efficiency improvement module, which employs the method of flexible load scheduling to achieve the best configuration of demand-side resources.
A Reinforcement Learning-based Approach for Active Optimization of High Proportional Distributed Power Supply Access to Rural Distribution Networks
Authors: Li Rui , Yan Tao , Zhao Yang , Zhang Jinming , Zhang Lu
Published: March 2023

In the process of actively implementing the rural revitalization strategy and the “double carbon” goal, distributed power sources are connected to the rural distribution network on a large scale, resulting in a gradual transition to a new type of active distribution network, which has a greater impact on the distribution network in terms of voltage, network loss, and protection, thus posing greater demands on the distribution network in terms of planning and control, power quality management, and operation. This significantly impacts the voltage, network loss, and protection of the distribution network, thus putting higher requirements on the planning and control, power quality management, operation, and maintenance of distribution networks. Since the traditional OPF algorithm has great defects in solving large-scale decentralized, time-series, and stochastic nonlinear problems, in order to realize real-time control of distribution networks under more complex network conditions, this paper proposes an optimization algorithm based on reinforcement learning and applies it to real-time control of active distribution networks, taking the optimal network loss as the objective function and considering network voltage, line load factor, and distributed power supply. As a de-modeling artificial intelligence method, reinforcement learning has great advantages in solving large problems with complex mathematical models. The method’s control effect and convergence time can be improved by introducing imitation learning and migration learning, expanding the knowledge matrix, and introducing risk assessment mechanisms. Based on MATLAB R2017a simulation platform for the IEEE 33-node improvement model, the simulation results show that the reinforcement learning method has a better control effect in solving the real-time control problem of active distribution network, significantly alleviates the voltage crossing limit, effectively reduces the network loss, and has good real-time characteristics.
An Intelligent System with Multiple Power Supply Modes
Authors: Yan Dong , Yang Wanyu
Published: March 2023

A low-cost and intelligent power supply system with an STC15 single-chip microcomputer as the main controller is designed. The single chip monitors the mains voltage and controls the relay to switch between the mains and battery power supply. Battery constant current, constant voltage, and floating charge intelligent charging management are achieved through the battery voltage execution. Through the ESP8266WIFI module networking, we can access weather information, and weather judgment, and choose whether to enter the battery mode, which can better protect the power system. The experimental results show that the system can operate reliably and complete the switch between mains supply mode and battery supply mode quickly.
A hybrid energy storage power system dispatch strategy for demand response
Authors: Chen Renhui , Guo Minghao , Chen Nan , Guo Xianting
Published: March 2023

In recent years, with the deepening global energy crisis and greenhouse effect, the trend of the power industry towards low-carbon and clean development has gradually increased. This is manifested in the power supply side and the load side, i.e., the power imbalance brought about by the uncertainty and volatility of both. Therefore, based on the above background, this paper first proposes a new power system consisting of renewable energy, hybrid electric-hydrogen energy storage, and fuel cells. Secondly, this paper proposes a commercial load dispatching strategy with a time-of-use tariff, which is solved by complex optimization to verify its economic advantages and feasibility.
Lightweight Design of Differential Thickness-Carbon Fiber Reinforced Plastic Car Seat Backrest
Authors: Wu Chao , Long Jiangqi , Ni Jimin
Published: March 2023

To realize the light weight of the seat back of a new energy vehicle, this study uses the idea of differential thickness to remove the reinforcing ribs of the seat back while meeting the requirements of performance and assembly of the carbon fiber seat back and then carries out the structural design and layer optimization of the seat back to minimize the overall quality of the seat back. The finite element model of the car seat is established by finite element analysis software, and the definition visualization of carbon fiber composite is realized in Hypermesh software. Finally, the light effect of the carbon fiber backrest of automobile seats is 22.1%, which meets the design purpose and requirement of the differential thickness of the backrest.
Research on the innovative design of the turning mechanism of high-power diesel engines
Authors: Gu Ding , Ren Kaifeng , Liu Yongqiang , Shi Jiaxin , Wang Liang
Published: March 2023

In response to the problems of excessive wear of the worm, complex overall structure, and cumbersome operation and maintenance procedures of the turning mechanism of high-power diesel engines, conflict areas are established to find the root cause. In this regard, the technical conflict model is established by analyzing the backlash between teeth. The design optimization is carried out by the invention principle to form a new structural design. And the reliability test verification is carried out to ensure good working performance in the maintenance cycle, thus reducing the application risk. Innovative design methods can be widely popularized in various working conditions such as assembly, debugging, and maintenance of high-power diesel engines, further promoting the innovation ability of high-power diesel engines in the field of research & development and application.
Simulation of Switched Reluctance Motor with an optimized Direct Torque Control minimizing Torque Ripple
Authors: Xia Hongji , Diao Han , Zhu Xiaoxiao , Cao Qixin
Published: March 2023

Switched reluctance motor (SRM) is paid more attention in industrial usage because of its simple structure and low cost. But the inherent torque vibration situation and noise caused by vibration limited its application in electrified vehicles, which requests sooth torque output. To meet the demand of minimizing torque ripple, this article presents a new direct torque control (DTC) method with a changeable reference flux and a more steady switching table to lower the torque ripple and power consumption. This new method is carried out by MATLAB simulations which show that the new DTC method enhances the response of the focused 4-phase SRM to reach the given speed faster and meanwhile minimizing the torque ripple compared to the traditional DTC method.
Finite element analysis on the propagation characteristics of laser-generated surface acoustic wave in V-groove weld
Authors: Li Ziming
Published: March 2023

Thick-walled structures, such as marine engineering and rail transportation, are widely used in modern society. V-groove welding is a common welding method in thick structures. At the same time, the V-groove weld is also the area of a thick-walled structure in which defects are most easily formed. Laser-generated surface acoustic waves are a promising non-destructive testing method in most fields. This study examined the propagation characteristics of laser-generated surface acoustic waves in a V-groove weld. A two-dimensional finite element model with Q345 steel was constructed. A thermoelastic mechanism was adopted to generate the wave. The temperature and displacement fields were analyzed in detail. The results showed that wave transmission, reflection, and mode conversion are generated with an R wave at the junction, and the dispersion phenomenon of the R wave occurred in the welded area.
Die level thinning after bonding on the substrate in 3D packaging
Authors: Wang Yao , Hu Chuan , Xiang Xun , Zheng Wei , Cui Yinhua
Published: March 2023

This paper aims to realize heterogeneous integrated packaging technology for high integration by applying a thinning process technology for controlling the thickness of chipsets used in packaging, i.e., A technology for processing silicon dies with a thickness of 100 um or less and a technology for handling thinning ultrasmall dies. We combine wet etching with dry etching to fit an effective and practical experimental plan. Anisotropic etching in KOH solutions and ICP etching of silicon die bonding on a glass substrate are investigated. Die with copper wiring is fabricated and pasted on the substrate to achieve selective etching of the whole device. The topography of the die surface and corner is analyzed to prevent the influence on the second layer stacking process.
Identifying the regional emergence of climate patterns in the ARISE-SAI-1.5 simulations
Authors: Labe Zachary M , Barnes Elizabeth A , Hurrell James W
Published: March 2023

Stratospheric aerosol injection is a proposed form of solar climate invention (SCI) that could potentially reduce the amount of future warming from externally-forced climate change. However, more research is needed, as there are significant uncertainties surrounding the possible impacts of SCI, including unforeseen effects on regional climate patterns. In this study, we consider a climate model simulation of the deployment of stratospheric aerosols to maintain the global mean surface temperature at 1.5 ∘C above pre-industrial levels (ARISE-SAI-1.5). Leveraging two different machine learning methods, we evaluate when the effects of SCI would be detectable at regional scales. Specifically, we train a logistic regression model to classify whether an annual mean map of near-surface temperature or total precipitation is from future climate change under the influence of SCI or not. We then design an artificial neural network to predict how many years it has been since the deployment of SCI by inputting the regional maps from the climate intervention scenario. In both detection methods, we use feature attribution methods to spatially understand the forced climate patterns that are important for the machine learning model predictions. The differences in regional temperature signals are detectable in under a decade for most regions in the SCI scenario compared to greenhouse gas warming. However, the influence of SCI on regional precipitation patterns is more difficult to distinguish due to the presence of internal climate variability.
The preliminary study on the historical governing law of the frozen estates in Kampong Bharu, Malaysia
Authors: Salleh R M , Malek N A A , Yusoff R M , Wahab N , Atan S M , Sainan Z
Published: March 2023

Kampong Bharu is situated in Kuala Lumpur, Malaysia and is categorised as a high commercial land located in the ‘Golden Triangle.’ However, this place is still left behind in terms of development as it is reported that there are more than RM60 billion in frozen estates. The existing legal framework is still considered inadequate as the planning development has been pending until today. Hence, this paper aims to analyse the legal history and the constraints preventing the development of Kampong Bharu. The discussion adopts the content analysis based on the qualitative research methods through the statutory provisions and other legal and non-legal literature. The research found that the Kampong Bharu Development Corporation Act 2011 was passed, and the Kampong Bharu Development Master Plan 2040 has been launched to carry out the development. Hence, it is proposed that the Kampong Bharu Development Corporation (KBDC) may have to wield the Land Acquisition Act 1960 so that the productive elements in Kampong Bharu can be activated. The impact of this research is in line with the benefit addressed by the Sustainable Development Goals (SDG) Plan (2030) in terms of making cities and human settlements inclusive, safe, resilient and sustainable.
Green roof installation as a living lab for outdoor learning in higher education
Authors: Amir A F , Akhir N M
Published: March 2023

Technology and construction knowledge are harder to understand among higher education students if the teaching and learning process is only conducted inside the classroom. Learning should be versatile, and the subject will be more interested in experiencing the students with materials and processes outside the classroom. It also boosts site awareness, especially when the students must collaborate on the design and construction technology for the site. Thus, a living lab approach was introduced to prepare students with sound designer and construction technical knowledge. The research aims to expose students and the community to extensive green roof installation as part of teaching and learning activities. The green roof subject was selected as it was an example of engaging design students with current technology. The participation from various student backgrounds are from Master of Science in Green Architecture, Bachelor of Science in Architecture, Bachelor of Science in Building Surveying, Diploma in Landscape Architecture and other communities from the nearby campus. The results show the materials and process of building an extensive green roof on campus and significant to the design and build consultant/contractor, academicians, students, and nearby community to understand the process involved in site. The discussion part elaborated on the issues of green roofs, such as managing green roofs and biodiversity.
Public perception and acceptance of tricycle as an option of transportation mode in Malaysia
Authors: Ishak S Z , Shabadin A , Mohd Maidin M A , Nemmang M S , Susilawati  , Kamaluddin N A
Published: March 2023

Transportation is important for the movement of people and goods from one place to another. The parameter of choosing the suitable mode of transport include the cost of service, speed of transport, flexibility, frequency of service, safety & security. Exploring an option for transport modes, this study aims to understand the public perception and acceptance of the usage of tricycles in Malaysia with the objective to benchmark the usage of these tricycles in other countries and measure the perception and acceptance of Malaysian towards tricycles. Public view and their acceptance were collected from 299 respondents via a structured online questionnaire survey. The survey has shown that public acceptance to accept tricycles is 39.3% for public transport, 62% for transporting goods, and the highest percentage for the use of People with Disabilities (PWDs) is 62.8%. Feedback on public perceptions based on six (6) factors was discussed. The advantages and the disadvantages based on the lesson learned from various countries were highlighted to support the findings.
Scenario of reducing carbon emission through shifting consumption of non-renewable energy to renewable energy in asia pacific 2023-2030
Authors: Aimon H , Kurniadi A P , Amar S
Published: March 2023

This research is motivated by the high level of carbon emission due to the dominance of non-renewable energy consumption in the use of the energy mix. This study aims to fill the gaps in previous research to support global programs in reducing carbon emission by designing scenario through a shift in consumption of non-renewable energy (fuel oil) to renewable energy (biofuel oil) in the Asia Pacific for future periods, including 2023-2030. The basic foundation of this research is the result of panel regression during the period 2006-2021. Furthermore, non-renewable energy consumption was reduced to three categories (pessimistic, moderate and optimistic), then the decrease was substituted for renewable energy so that the community’s energy needs were still met. The important finding from this research is the consumption of renewable energy and green economic growth can reduce carbon emission, while the consumption of non-renewable energy increases carbon emission. In addition, average carbon emission decreased growth in each scenario, including 15% on the pessimistic, 32% on the moderate and 66% on the optimistic. The policy for reducing carbon emission is to strengthen coordination between domestic institutional structures to develop alternative energy and also implement green economy programs in economic activities.
Effectiveness of deep eutectic solvents for light oil recovery through spontaneous imbibition
Authors: Ganesan D , Hamdi Z , Cheong W C
Published: March 2023

With the rise in demand for energy, comes the need to extract oil from not only primary and secondary stages, but also from tertiary recovery methods to keep up with the current market. Enhanced oil recovery (EOR) has become more prevalent within maturing reservoirs. Ionic liquids (IL) were highly regarded for chemical EOR until researchers raised concerns about their expensive cost, toxicity, and environmental impacts. Recently, deep eutectic solvents (DES) were discovered as a potential replacement for ILs due to their non-toxic nature, being biodegradable, non-flammable, and cheaper. In this study, the effectiveness of DES is investigated by observing its ability to promote oil recovery through wettability alteration. Spontaneous Imbibition tests along with emulsion and thermogravimetric tests (TGA) are used to achieve the objectives. Results indicated that both DESs can recover oil that was not recoverable using brine only. At higher temperatures, the effectiveness of DES was higher, which allowed for more oil to be imbibed out. The effect of concentration suggested that at high concentrations, DESs exhibit self-destructive properties by increasing interfacial tension (IFT), which reduced the imbibition rate and recovery factor. TGA studies indicate that the thermal stability of DESs is highly dependent on the thermal stability of their hydrogen bond donor (HBD).
Financial feasibility study of briquette production from used charcoal and tree branches in Kampung Oase Ondomohen Surabaya
Authors: Zunaidi R A , Deria D D , Amiroh K , Annisa A R
Published: March 2023

Population growth in Indonesia continues to increase from year to year. By 2035, it is predicted that 70% of Indonesia’s population will be urbanites. The potential for sustainable urbanization and regional development has encouraged the Surabaya City Government to turn some of its areas into foster villages, one of which is Kampung Oase Ondomohen. The village was named Kampung Oase because of the village’s high initiative to process waste into high-selling value products, one of which is briquettes that come from the waste from burning Sate Klopo Ondomohen and tree branches around the village area. Using charcoal and tree branches in making briquettes is the main focus of managing organic waste to be used as a renewable energy source. Before the mass production of briquettes, a study on feasibility analysis is needed, especially financial feasibility analysis, aims to assess whether a business can provide optimal financial benefits for its owners. The financial feasibility criteria used in this study are the Internal Rate of Return, Net Present Value, Payback Period, and Net Benefit/Cost Ratio. From the calculation of the four financial feasibility criteria, IRR value is 41,53%, NPV value is IDR 35,732,432.20, PBP is 2.81 years, NBC Ratio is 1.226, so the production of briquettes in Kampung Oase Ondomohen is feasible to run on a larger scale.
Nickel based catalysts supported on porous support for methane steam reforming: potential and short review
Authors: Seman M H A , Othman N H , Osman N , Jani A M M
Published: March 2023

The world is now demanding other sustainable energy that can help explore new technologies, especially energy conversion and storage. Hydrogen is regarded as one of the most promising oils and gas successors as a fuel due to its high energy content per unit mass and it burns completely free of pollutants. A widely used method for hydrogen production is steam reforming methane (SRM) from biogas. In the SRM process, using a catalyst is crucial, and, if compared to the available metal-based catalysts, Ni-based catalysts provide an acceptable high activity and a lower cost. In addition, the support material of a catalyst significantly affects its stability, especially for catalysts exposed to elevated temperatures. In this work, porous alumina support was used as a support material for the preparation of a nickel-based catalytic hollow membrane reactor. Porous alumina support was fabricated using a double-step anodization method. The presence of large pores (≈120 nm) on support material contributes to decreasing the resistance to mass transfer. The study also highlights the recent progress on methane steam reforming reaction, giving a short overview of catalyst utilization and the fundamentals of SRM through the developed membrane reactor.