bluuebunny/crossref_metadata_2025 huggingface dataset:
Computational design optimization of industrial single piece ball valve to enhance the flow performance
Authors: Rangappa Ravichandra , Murthy BRN , Porali Avinash , Rajesha S , Natarajan N
Published: November 2021

The characteristics of flow through the fluid flow system largely depends on the control valves and their performance. Ball valves are one among the major valves widely used in various industries due to their simple construction and ease of manufacturing. Thus investigating flow characteristics of these valves is most essential to minimize the losses due to friction and cavitation caused within the valve body. The main objective of the current work is to carry out the computational fluid dynamics analysis using Ansys® Fluent® as solver and Solidworks® as 3D modelling tools to investigate the flow patterns through the single piece ball valve to determine the various flow characteristic and there by suggest design optimization for improved flow rate and performance. Various designs of ball valve such as BVD1, BVD2 and BVD3 were tested through CFD simulation. The simulation results reveals that BVD1 and BVD2 are failed in bidirectional flow characteristics. However BVD3 shows the significant improvement in all the flow characteristics.
Conversion of Two-Stroke Vehicle to an Electric Vehicle
Authors: Harris Haroon Rayyan , Dev Ajay G , Jose Joel , Jithamanyu Dv Ganesh , Sankar Vishnu , Noble Jibin
Published: November 2021

Amid the global pandemic of covid-19, fuel prices have soared a record high, crossing the Rs. 100 landmark for petrol and diesel. This leads to an increase in prices across all products, which cuts in deeper into the already thin bottom lines of ordinary citizens. Public outcry aside, the rise in fuel prices indicates an accelerating trend, which emphasizes the need to find alternative sources of fuel for transport; the ever growing sector. In recent years, reports of possible banning two-stroke engines, coupled with the emergence of a new emission standard in India, have re-ignited questions about how two-stroke vehicles, can be powered from alternative sources of energy. This project intends to address the above question, by assessing the feasibility of a different alternative, by designing an electric drivetrain for a twowheeler, while aiming to be practical and economical for the ordinary man riding it. This project intends to be a cost-feasibility study, whose aim, to realize a full EV conversion of a twowheeler, less than 50% of current market price of base level, original EV’s, thereby proving to be a feasible alternative to people who cannot afford the alternative; and also solving the logistical and environmental problems arising from a large number of abandoned or suboptimal use of such vehicles, when the shift happens.
Design and Control of an Automated SCARA Robotic Arm with a Pneumatic Soft Gripper
Authors: Pranav V K , Kumar G Nitheesh , Yadukrishnan V , Anil Krishnanand , Ghanashyam S , Prakash Amal , Rajendran Anikesh , Sreedharan Pramod
Published: November 2021

The paper focuses on the design, analysis and control of an automated 3 DOF SCARA robotic manipulator with an end effector made of asymmetric flexible pneumatic bellow actuator (AFPBA). The manipulator is made for use in the poultry industry and therefore tested in its ability to detect, pick and place eggs. The links of the manipulator are made using acrylonitrile butadiene styrene (ABS) and the end effector is made using nitrile rubber. A neural network derived from the VGG-16 and YOLO architecture is then implemented to detect and localize eggs. The predicted values were then used to calculate the inverse kinematics of the manipulator.
Effect of addition of bio-additive clove oil to ternary fuel blends (Diesel-Biodiesel-Ethanol) on compression ignition engine
Authors: Nair Jayashri N. , Singh Thokchom Subhaschandra , Raju Vallapudi Dhana
Published: November 2021

The use of biodiesel reduces emissions like hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO2), particulate matter (PM); but increases nitrogen oxide emissions. Additives inculcated in diesel and biodiesel has served as one of the means to decrease NOx emissions. An attempt is made to investigate the effect of the addition of ethanol and clove oil, to Pongamia biodiesel, on performance and emission characteristics. Pongamia biodiesel was extracted by transesterification using potassium hydroxide (KOH) as a catalyst. 5% Ethanol and 0.5 and 1 ml clove oil were added to the esters produced. B20 (20% biodiesel + 80% diesel), B20E5 (20% biodiesel + 75% diesel +5% ethanol), B20E5CL0.5 ( 20% biodiesel +75% diesel+5% ethanol +0.5 ml Clove oil) and B20E5CL1 (20% biodiesel + 75% diesel+5% ethanol +1 ml Clove oil) were analysed. The test was performed on a single-cylinder, four-stroke engine connected to an eddy current type dynamometer for loading. The addition of 1ml of antioxidant (clove oil) resulted in an increase in brake thermal efficiency by 8.9% and brake specific fuel consumption marginally by 1.53 %. At higher loads, the B20E5CL1 blend showed a 13% reduction in NOx emission. B20E5CL1 blend also resulted in a reduction in CO emission at higher loads. Ethanol addition to the biodiesel (B20E5 blend) resulted in the highest brake thermal efficiency but at the cost of NOx emissions. Blends with ethanol and clove oil reported good results at higher loads.
Assessment of Spatial Distribution of Physico-Chemical Parameters of Groundwater around Kodungaiyur Dump yard
Authors: Aishwarya R
Published: November 2021

Municipal solid waste management has become an acute problem due to enhanced economic activities and rapid urbanisation. In most cities, solid waste is disposed of in open dumps without proper lining which has tremendous health issues and environmental effects. Kodungaiyur dump yard chosen for this study is the major toxic dump yard in Chennai. In recent years there has been a serious concern about the deteriorating groundwater quality due to leachate contamination. Despite posing strict rules on pollution of water bodies, water continues to be consistently underappreciated and undervalued. So, the present study is emphasized on the ill effects of leachate percolation on groundwater quality and is also represented spatially to understand the impact of the landfill in the selected area. For this study water samples are collected from 12 bore wells in and around Kodungaiyur dumpsite and they are tested for various Physico-chemical parameters like total alkalinity, total dissolved solids, hardness, conductivity, pH, sulphate, chloride, potassium, sodium, Magnesium, and nitrate. The water samples are also analysed for BOD, COD and heavy metals include Cd, Cu, Fe, Pb and Ni. The test results are compared with Water quality standards. The spatial distribution of the Physico-chemical parameters is represented in maps prepared using Quantum Geographical Information System (QGIS). The result obtained from testing and spatial representation using GIS helps in monitoring and managing water contamination in the study area.
Optimization of multiple quality characteristics for end milling under dry cutting environment using desirability function
Authors: Sarath V V N , Tamiloli N
Published: November 2021

Milling AA6082T6 materials is a difficult venture because of their heterogeneity and a slew of problems, inclusive of surface roughness, that get up for the duration of the machining method and are connected to the material’s homes and slicing settings. The optimization of machining parameters is a crucial section inside the manufacturing method. This research introduces a unique approach for improving machining settings whilst milling aluminum alloy. A technique notorious as desirability function analysis (DFA) turned into worn to optimize machining parameters. DFA is a effective tool for optimizing multi-reaction problems. Milling research for aluminum alloy were completed using tungsten carbide end milling inserts in dry situations, based totally on Taguchi’s L9 orthogonal array. Multi-response issues, along with machining pressure and surface roughness, are used to optimize machining parameters including feed charge, spindle speed, and depth of reduce. person desirability values from the desirability characteristic analysis are used to create a composite desirability cost for the multi-responses. The most effective ranges of parameters had been discovered based at the composite desirability fee and substantial contribution of parameters has been determined the usage of analysis of variance.
Experimental Investigation on Sound Absorption Property of a Panel Board Using Maize Stem
Authors: Ramshankar P , Sukumar Binu , Kumar S Kishore , Karan V , Karthick C
Published: November 2021

In this project our aim is to produce a soundproofing board which is made out of Maize stem (stalk). Due to increase in number of industries, factories and vehicle traffic cause serious noise pollution. So to overcome this, use of Sound proofing panels in the structural elements could significantly help to reduce the sound as well as gives a good environment to work. People nowadays demand for a better working environment. Many commercialized sound proofing materials are available in the market, the cost of these materials would be much higher and also it could cause health issues when people are exposed with the material. So use of sound proofing panels made with agro-waste could be a better solution, an attempt has been made to produce a soundproofing board which is made out of stalk portion of maize plant. The board’s sound absorption property is studied in this research by using Impedance test and the cost of maize stem board is cheap enough so that everyone can afford it.
Simulation-Based Comparative Study on Energy Efficiency Criteria for LEED and BREEAM Systems
Authors: Harisankar R , Rakesh P
Published: November 2021

Energy efficiency is regarded as one of the important elements of green building. Every Green Building Rating (GBR) system puts forward a set of criteria for energy efficiency and it is different for each system. A comparative study is done to distinguish between two GBR systems practiced worldwide-LEED and BREEAM, first on the criteria for energy efficiency and secondly on how efficient and effective each system in energy performance improvement. Building energy simulation tool, eQuest is used to obtain annual energy consumption of a case study multi-family dwelling residential building for its various design options. Different design cases were formulated by changing design parameters and the simulation results thus obtained are used for evaluating the performance improvement for energy, calculated as per the criteria for each system. This study primarily looks for the combinations which grab total achievable credits in energy efficiency for a particular system. For LEED, it was found that renewable energy allocation alone has the greater influence in achieving higher credits. For BREEAM, there requires specifically a considerable decrease in HVAC load which can be brought by the means of more natural ventilation or by adopting passive cooling techniques. BREEAM was also found more effective in reflecting any kind of improvement made in terms of awarding credits.
Studies and Practice of Geometrical Test Procedures & Reconditioning of CNC Lathe Machine Tool
Authors: Beno Jerin , VeeraBhadra Rao M , Das Sunil Kumar
Published: November 2021

Machining Centres have been major production units for many decades with desired levels of accuracy, economy in costs of production and ease of control. Though new disruptive technologies such as rapid manufacturing, near net shape manufacturing technologies are replacing these machining units, still small and medium Indian Industries go with the conventional ways of large-scale production using conventional and classical machining approaches. With huge setups in place, such machines with high productivity demands, require stringent parts alignment tests frequently from time to time, referred to as Geometrical or Alignment tests to enable accurate finishing and machining of parts and smooth and uninterrupted production. This paper puts forth some basic Geometrical Tests performed on SB CNC 60 Lathe Machine Tool unit, identifying major deviations measurements and reconditioning the machine parts. The main objective of running such tests is to prevent breakdown of the machine and ensure safety working when handling older and heavier conventional machines.
Embodiment design of a soil bin for soil-tool interaction study
Authors: Karmarkar A U , Gilke N R
Published: November 2021

The agriculture industry is an important aspect of Indian economy. The changes occurring in global climate and increased frequency of extreme weather conditions pose challenges for agriculture industry. In such unpredictable conditions, achieving required outputs from farming for supporting continuously increasing population necessitates the mechanization of traditional processes. The selection of machinery for such mechanized setup is a key management task. Tractor is one of the farm machines being used in various farm related operations. Thus understanding constraints imposed on selection of a tractor is a primary factor in decision making process. The study has highlighted importance of power requirement for farming operation in tractor selection process. Thus to determine power requirement for farming operation a study of soil-tool interaction is necessary. A soil bin setup is one of the tools for studying the soil-tool interaction. This work presents the conceptual and embodiment design of a soil bin developed to find variation in draft force with respect to variations in the parameters like tillage depth, operation speed and soil moisture level. The tillage depth and operation speed were found to be directly proportional whereas the soil moisture level was found to be inversely proportional to the draft force.
Impact of dyeing industry effluents on geotechnical properties of soil
Authors: Karthika T , Shalini S , Kothai P S , Arumugam K
Published: November 2021

In developing countries concentration on pollutants produced by industries such as dyeing, tanneries industries are exceptionally high. The disposal of untreated industrial waste water similar to dyeing effluent on soil is a widespread practice in developing nations. The unprocessed effluents severely deteriorate the soil properties. The study on dyeing effluents from industries affects engineering properties of soil. Hence the soil properties have to be improved for intensification of soil for the constructional activities. The soil properties are very much exaggerated by dyeing effluent which produces the soil and water pollution. In this study textile industry effluent is taken as pollutants and laboratory experiments are carried. The affected soils were treated with marble dusts as admixture to improve the soil properties. For assessment polluted and unpolluted soil samples are treated with 20% of dyeing effluent and tests were conceded out to identify an extent of the contamination. The cured samples show a decrease in strength values up to 30% with raise in the percentage of infectivity (dyeing effluent). The geotechnical properties and their stabilization using marble dust are determined with mixtures and explored.
Surface Roughness Prediction using Machine Learning Algorithms while Turning under Different Lubrication Conditions
Authors: Varun A , Kumar Mechiri Sandeep , Murumulla Karthik , Sathvik Tatiparthi
Published: November 2021

Lathe turning is one of the manufacturing sector’s most basic and important operations. From small businesses to large corporations, optimising machining operations is a key priority. Cooling systems in machining have an important role in determining surface roughness. The machine learning model under discussion assesses the surface roughness of lathe turned surfaces for a variety of materials. To forecast surface roughness, the machine learning model is trained using machining parameters, material characteristics, tool properties, and cooling conditions such as dry, MQL, and hybrid nano particle mixed MQL. Mixing with appropriate nano particles such as copper, aluminium, etc. may significantly improve cooling system heat absorption. To create a data collection for training and testing the model, many standard journals and publications are used. Surface roughness varies with work parameter combinations. In MATLAB, a Gaussian Process Regression (GPR) method will be utilised to construct a model and predict surface roughness. To improve prediction outcomes and make the model more flexible, data from a variety of publications was included. Some characteristics were omitted in order to minimise data noise. Different statistical factors will be explored to predict surface roughness.
Squeezed states generation in an array of Linear and Nonlinear Waveguides
Authors: Julius R , Ibrahim A-B M A , Alias A N , Halim M S A
Published: November 2021

We demonstrate the generation of squeezed states of light due to the second harmonic generation and Kerr effect in an array of nonlinear waveguides mediated through a linear one. We characterized the electromagnetic field by a quantum mechanical Hamiltonian and the density operator time evolution is obtained from the Von-Neumann equation of motion. Using the quasiprobability positive P of phase space representation, the classical Fokker-Planck equation is obtained from the master equation and translated to its classical matching set of nonlinear differential equations. We showed that because of the new possibilities of correlation between the linear and nonlinear channel waveguides, highly nonclassical light may be produced.
Silver Nanoparticles Embedded in Polyvinyl Alcohol Based Passive Saturable Absorber
Authors: Rashid N N M , Lokman M Q , Nordin N A , Yahaya H , Ahmad F
Published: November 2021

Silver nanoparticles (AgNP), a novel candidate of noble metal nanoparticles, which has great potential for pulsed laser applications due to strong saturation absorption behaviour. This study demonstrated the passively Q-switched laser operating within an Erbium-doped fibre laser cavity using AgNP saturable absorber (SA). The AgNP was synthesized via the chemical reduction method and the average size of nanoparticles was around 52.39 nm. The AgNP was incorporated with polyvinyl alcohol (PVA) polymer to form an AgNP-PVA composite SA. The proposed experimental works generated single pulse energy and peak power of about 66.14 nJ and 18.71 mW corresponds to the repetition rate and pulse width of 62.89 kHz and 3.32 µs.
Characterization of cost-efficient OPT101 PIN photodiode as relative dosimetry in diagnostic radiology: An IOT application
Authors: Radzi Y Md , Zainol M K , Al Naggar A S A
Published: November 2021

OPT101 photodiode sensor dosimetry properties were investigated for various parameters to observe its capability as a relative dosimeter. Its characterization was done with PTW semiconductor detector for diagnostic radiology as a benchmark. OPT101 presented excellent output linearity relative to dose measured by PTW semiconductor for energy dependency and reproducibility test. A significant high sensitivity was observed against dose rates and mean energies and linear response against different source-to-detector distance, SDD. Results suggest the use of an Arduino IDE microcontroller as potential of utilizing an IoT application in input/output communication with the sensor and data processing.
Investigation on Identification of RRIM Clone Series using Various NIR LED sensor
Authors: Abdullah N.E. , Baddri M. S. , Madzhi N.K. , Hassan S.L.M. , Halim I.S.A. , Rahim A.A.A.
Published: November 2021

The evolution of various rubber tree clone has been introduced by Malaysian Rubber Board since 1928 and it is known as Rubber Research Institute Malaysia (RRIM) clone series. To support this, it is suggested research to investigate the behavior of the clone series with the development from a sensing device with several opted NIR wavelength ranges through the latex samples. An optical sensor prototype has been built consist of four types of NIR LED at selected wavelength and the photodiode works as receptor of the light emission. As transmitter, the NIR sensors are obtain from the local distributor in Malaysia which is RC component. Arduino Uno is use as the processor for processing the data and obtain the output trough LCD. There are five selected clone use which are RRIM 3001, RRIM 2008, RRIM 2007, RRIM 2014 and RRIM 2002. The output result which represented by the voltage and then will be analysed using statistical analysis approach for data analysis. The outcome reveal that the selected rubber tree clone series is able to determine based on the NIR properties.
Random laser behavior in Gold-doped Zinc Oxide nanorods structures
Authors: Ali Abdullah Taha , Maryam W. , Huang Yu-Wei , Hsu H.C. , Ahmed Naser M. , Zainal N. , Abu Hassan H.
Published: November 2021

The random laser was investigated in gold-doped Zinc Oxide nanorods (Au-doped ZnO NRs) under a range of pumping power 0.25 - 4.66 mW. The Au-doped ZnO NRs prepared by chemical bath deposition (CBD) on the ZnO seed layer, were pre-coated on glass substrate using radio frequency magnetron sputtering (Rf-sputtering). The morphological of Au-doped ZnO NRs shows a hexagonal and strong vertically alignment against the substrate. The Energy dispersive spectroscopy (EDX) spectrum and elemental mapping results confirmed that Au atoms (at.%) are doped and spread over the ZnO NRs. More interestingly, the random laser of Au-doped ZnO shows a redshift of ~38 nm. This study showed the ability of using doping as a tuning parameter in the random laser, also provided an emphasis on Au-doped ZnO NRs as suitable options for controllable random laser devices.
A Study of Optical Micro-bottle Resonator Humidity Sensor
Authors: Mohamad Ali Ummu Umairah , Johari Ahmad Ashadi , Jusoh Zulzilawati , Rahman Husna Abdul , Harun Sulaiman Wadi
Published: November 2021

This experiment reports the fabrication of the optical Micro-bottle Resonator (MBR) as a relative humidity (RH) sensor. The MBR is fabricated via the “soften-and-compress” method to create the bottle-shaped with diameter Db = 175 um. The MBR is then optically excited using a 8 μm microfiber and was found to have a Q Factor of >105. The MBR was then employed as a humidity sensor with the RH level percentage range between 40% to 100% and the performance is compared with a non MBR microfiber. The MBR sensor was found to have a sensitivity of 0.2973 dBm/%, linearity >90% and and is superior to the bare microfiber in all measured parameters. The MBR humidity sensor was also found to have good repeatability and stability over a period of 60 seconds compare to bare microfiber.
Design of the logic protection for the mechanical elastic energy storage system
Authors: Zheng Xiaoming , Xi Guoping , Gao Xuejiang , Ma Yunfeng , Zhao Chao , Zhang Xin , Wang Peng
Published: November 2021

The operation procedure of the mechanical elastic energy storage unit is complex, and multiple devices need to cooperate with each other. These devices need to operate in turn according to the specified procedures to complete the operation process of unit energy storage and power generation. At the same time, before the unit operation, it is necessary to make a logical judgment on whether to execute the control command according to the state of each device, and display the normal or fault of each device in the state display area. The PLC has the advantages of flexible use, strong universality, high reliability and strong anti-interference ability. It is suitable for designing mechanical elastic energy storage logic protection system. This paper designs the logic protection system of mechanical elastic energy storage unit based on the PLC. The system has the advantages of convenient use, simple operation and good stability. The correct logic action can control the unit to execute accurately, which plays an important role in ensuring the safe operation of the unit.
Optimal Design of Three-way Joint Structure for Steam Pipeline of Offshore Floating Nuclear Power Plant
Authors: Dai Chunhui , Lao Xingsheng , Song Ping , Chen Lie , Zhang Kelong
Published: November 2021

Offshore nuclear power plants have many advantages, but their small space determines that operators cannot work far away from the steam power generation system. In order to improve work comfort and reduce noise damage, this article has carried out optimization design work for the three-way joint of the steam pipeline. On the basis of the female model, a smooth numerical simulation of the three-way joint is carried out to show its internal flow field. On this basis, with the uniform optimization design method, the best branch rounding radius of the confluence tee joint and the branch tee joint were obtained respectively.
Load balance control method of multi electromechanical transmission system based on dynamic programming
Authors: Zhou Liping
Published: November 2021

Controlling the load balance of multi electromechanical transmission system is the core and difficulty of metro vehicles. In order to effectively control the load of multi electromechanical transmission system and ensure the load balance of multi electromechanical transmission system. A load balancing control method of multi electromechanical transmission system based on dynamic programming is proposed. By designing the structure of the transmission system filter, the low DC resonant frequency of the inverter is maintained and the grid harmonics with higher order effect are suppressed. The rotor field oriented correction method based on dynamic programming can improve the torque performance of traction electric drive system, control the DC side active damping oscillation, and realize the load balance control of multi electromechanical drive system. The simulation results show that the proposed method avoids the wrong rise of multi electromechanical voltage and the saturation of regulator output caused by inaccurate magnetic field orientation, can effectively control the load of multi electromechanical transmission system, ensure the load balance of multi electromechanical transmission system, and provide an effective reference for the load balance control of multi electromechanical transmission system.
Design of sweep frequency signal source in residual stress detection platform based on Zynq
Authors: Yang Lei , Li Zhipeng
Published: November 2021

The signal generator based on DDS technology has high frequency and resolution, and is widely used in many fields such as instrument technology, radar, satellite timing, remote control and telemetry, and is one of the important directions of current signal generator research. In order to achieve a cost-effective, high frequency resolution signal source to stimulate the sensors in the residual stress detection system, this paper selects the Zynq-7020 on-chip system to control the 14-bit direct digital frequency synthesis chip AD9954 to obtain a 40Hz~1MHz sinusoidal signal output. Finally, the performance and technical parameters of the system are tested experimentally. The output signal of the signal source is stable, the signal-to-noise ratio is high, and the frequency error is within 0.1%.
Modularization and Parametric Design of Airborne Electronic Equipment Structure
Authors: Wang Yang , Li Siran , Wang Xiaofei , Wang Yue
Published: November 2021

In order to improve the design efficiency and quality of traditional airborne electronic equipment, the structural forms of traditional equipment are summarized. Based on the creation of basic structure modules, the parametric design of series structure modules and access devices is carried out. According to the functional requirements of the equipment, different series of structural modules are selected, combined and installed in the access device to quickly realize the modular design of airborne electronic equipment. A series of structural modules are repeatedly applied on a variety of equipment to improve the design reliability.
Research on Tracking Control of A Quadrotor UAV Based on Model Predictive Control and PD Control
Authors: Yu Jimin , Yong Zhi , Wang Yousi
Published: November 2021

In order to solve the problem of path tracking of a quadrotor UAV, this paper proposes a track tracking control method which combines Model Predictive Control algorithm and PD control method. Model Predictive Control algorithm can generate control input for formation flight and track the specified trajectory. PD control can achieve rapid response to attitude and adjust error quickly. The simulation results verify the effectiveness of the proposed control method.
The innovative design of balancing mechanism by TRIZ
Authors: Ma Shuai , Shi Yue-Jiang , Gao Yun-Kun , Sun Yue , Zhang Na , Wang Yu-Xiang , Zhou Shi-Gang
Published: November 2021

In this paper, an innovative design of balancing mechanism is completed after solving the problem of collision between balancing weight and barrel by TRIZ. For the original design of adding a balancing weight, the Functional Model Analysis is set and the key point of the collision problem is found. For the sake of improving the original design, this paper find out the key point of collision problem and adequate analysis by TRIZ theory, and proposed an innovative solution at last.
Development of automatic inspection device for pipe inner surface
Authors: Pan Shuo , Shao Xinjie
Published: November 2021

Aiming at the problem of 3D measurement of the inner surface of pipe, this paper develops a new structure of pipe inspection device inside the pipe based on the principle of laser triangulation. The device is composed of motion mechanism and image acquisition system. The three-dimensional shape of the inner surface is reconstructed the image pixel offset. The detection device driven by the motion mechanism can realize the automatic detection of different positions. The experiment shows the steps of the three-dimensional measurement of the inner surface of the pipe, verifies the feasibility of this method.
Research on reliable sealing technology of spacecraft rectangular hatch based on boundary control
Authors: Wang Yan , Li Yun , Zhuang Yuan , Zhao Benhua , Ren Huaxing , Wang Yongli
Published: November 2021

In view of the large size of the sealing surface of the space large diameter rectangular cabin door, the large number of locking mechanisms and long service life, it is difficult to adjust the multi degree of freedom attitude in the assembly process, the complex assembly and adjustment of the mechanism, the synchronization accuracy is not easy to ensure, the consistency of the multi-point seal compression rate is high, and it is not easy to control. Based on the rotation law of the spatial linkage mechanism, the precise dimension chain control of the hatch is carried out, and the attitude of the multi degree of freedom linkage is adjusted to realize the synchronous compression of multiple compression units of the compression mechanism; Based on the minimum and maximum operating force as the boundary, through the sealing stress simulation, the “boundary control” coupling assembly and adjustment technology is proposed to optimize the sealing structure and realize rapid and efficient assembly. The results show that the vacuum leakage rate is still less than 2.5×10−3 PaL/s after 2000 door opening and closing tests and sealing compression ratio are better than 15%. The long-life test verifies the feasibility and effectiveness of this method, and forms a set of high reliable and long-life sealing assembly and adjustment method of space hatch, which provides technical guidance and reference for the subsequent assembly of similar space hatch mechanisms.
Wind power short-term power forecasting based on Improved Grey Wolf algorithm and Optimized Generalized Regression Neural Network
Authors: Hu Yiwen , Gao Yang , Yang Shuai
Published: November 2021

Aiming at the problem of wind turbine output prediction, a wind power prediction method based on Improved Gray Wolf algorithm and optimized generalized regression neural network is proposed in this paper. Firstly, according to the daily similarity of wind speed and wind power, cluster analysis is used to classify the data. Considering that the degree of each factor affecting wind power output changes, based on the selection of similar days, an improved gray wolf algorithm is introduced to optimize the weight of each influencing factor. The two models of the first mock exam are selected to input the radial single mode function RBF and the back propagation (BP) network to predict the output of the wind turbine separately. The prediction results of the two models are input to the generalized regression neural network optimized by the Wolf Wolf algorithm and the nonlinear combination forecasting is carried out. The basis models are used to predict the output of the wind turbine. The example analysis of an area shows that the model can be closer to the real value in the peak and valley of the prediction curve and has higher prediction accuracy than the combined prediction model of single BP, RBF and non optimized general regression neural network (GRNN).
A DT-RSDM Model
Authors: Li Linxi
Published: November 2021

With rapid development of Digital Twin (DT), it seems that DT is vital to realize Cyber-Physical System (CPS) with the aid of dynamic interaction between digital twin and physical counterpart. In radar applications, digital twin can solve inherent shortfalls in radar structure design including ideal design description, poor dynamic interaction and limited implementation extension. Thus, a new DT-driven 5S Radar Structure Design Model (DT-RSDM) is proposed in this paper, focusing on improving radar structure design effectiveness and efficiency by employing iterative design optimization, design knowledge management.
Study on stud performance of steel UHPC composite structure based on temperature
Authors: Yang Pengcheng , Teng Xuqiu , Guo Haidong
Published: November 2021

The stress and deformation of the specimen under static load and temperature load coupling are deduced by simulation. With the help of finite element software ABAQUS, the user subroutines DFLUX and FILM are called to introduce the temperature field, so as to realize the analysis and Research on the stress, displacement, PEEQ, arrangement and load slip curve of the stud under different action conditions. The results show that based on the existence of temperature stress, the service performance of studs under coupling action is significantly lower than that under static action alone, and the proportion of shear performance of studs in different rows is different. Through the research and analysis of the above phenomena, it can provide reference value for the research of temperature on the performance of studs in composite bridge deck and prolong the service life of bridge deck.
Numerical Simulation on Enhanced Heat Transfer of Metal Foam Based on LBM
Authors: Li Zhongli , Hu Peng
Published: November 2021

Open cell foam metal has the characteristics of high porosity and large specific surface area. And it has developed rapidly in the related research of heat exchanger. Aiming at the convective heat transfer process of open cell metal structure with high porosity, a two-dimensional stochastic distribution model is established. Numerical simulation is carried out using the single-relaxation-time dual-distribution-function lattice-Boltzmann-method (BGK-DDF-LBM). For the non-ideal solid particles with unequal diameter and incomplete circular structure, the flow field is analyzed by taking the porosity of 0.964 as an example, and the dimensionless permeability is calculated. When the porosity is constant, the Nusselt number of the porous section increases with the increases of Reynolds number in the range of 10 to 100, which shows heat transfer performance. In addition, the Nusselt number of the porous section increases with the increase of porosity in the range of porosity from 0.900 to 0.980.
Carbonyl-based polyimide immobilization on carbon nanotubes for aqueous zinc-ion batteries
Authors: Li Kang , Wang Heng-Guo
Published: November 2021

The aqueous-based zinc-ion batteries (ZIBs) with higher safety and performance have gained great attention from scientists. Nevertheless, previous electrode materials mainly rely on inorganic metal oxides, and their structure is prone to collapse during charge and discharge, thus resulting in poor cycle stability, which severely limits the development of ZIBs. Here, a novel conjugated polyimide based conjugated microporous polymer (CMP) and multi-walled carbon nanotubes (CNT) hybrid has been gained and used as cathode material for ZIBs. The aromatic carbonyl group as active site can reversibly receive and release zinc ions, thus showing good electrochemical performance. This work provides new view for the design of high-performance ZIBs electrode materials.
Study on properties of 18MND5 steel forgings for PWR steam generator
Authors: Li Chan , Xu Yuting , Han Dongao , Fan Guohui , Yang Chenggang
Published: November 2021

In the pressurized water reactor (PWR) nuclear power plant, the shell material of steam generator is required to have good strength-toughness matching, anti-fatigue performance, and neutron radiation resistance to ensure the long-term safe and reliable service. The manufacturing requirements of Manganese-Nickel-Molybdenum alloy steel forgings of steam generator channel head for Hua-long Pressurized Reactor (HPR1000) and Advanced Passive PWR(AP1000) nuclear power plant were compared. The heat treatment process, chemical composition, mechanical properties, metallographic structure of 18MND5 steel forging and SA 508-III steel forging were analysed and studied. The results show that the performance heat treatment temperature of HPR1000 forging has more stringent controls and with lower element content of C, Mo, P, Si, V, Co than the AP1000 forging. By reducing the C content, HPR1000 forging got better toughness while the strength was ensured.
Crystallization and Dielectric Properties of BaO-SrO-PbO-TiO2-Nb2O5-SiO2 Glass-Ceramic Composites with La2O3 Addition
Authors: Zhang Qingmeng , Chen Junyou , Zhou Min , Zhao Yanyun
Published: November 2021

Glass-ceramic composite samples with different La2O3 content were prepared via melt-quenching followed by controlled crystallization. X-ray diffraction(XRD) analysis reveals that when the addition amount of La2O3 in the glass sample is less than 1mol%, two phases of perovskite structure and tungsten-bronze structure are formed after annealing at 1000°C for 3h. When the addition amount of La2O3 in the glass sample is increased to 2mol%, a new phase of pyrochlore structure is formed. Moreover, the addition of La2O3 causes the change in the lattice parameters of the glass-ceramic crystal phase. The microstructure observed that the ceramic phase grain size is in the nanometer level. The shape of some grains becomes an elongated structure when the La2O3 content in the sample increases to 2 mol%, and the grain size is increased significantly. The dielectric constant of the BaO-SrO-PbO-TiO2-Nb2O5-SiO2 glass-ceramic system is decreased with the increase of La2O3 addition, and the dielectric loss of the sample is decreased to the range of 0.003-0.008. The electric field stability of the dielectric constant was significantly improved with the addition of La2O3, indicating that adding a certain proportion of La2O3 to the BaO-SrO-PbO-TiO2-Nb2O5-SiO2 glass-ceramic system can effectively improve the dielectric properties, and it has a promising application as a dielectric material.
Study on constitutive relationship of acicular wollastonite polypropylene hybrid fiber concrete under uniaxial compression
Authors: Yan Xu , Liu Hao , Liu Yang , Xie Jin
Published: November 2021

In order to study the influence of fiber parameters on the performance of ordinary hybrid fiber concrete, the corresponding constitutive relationship of hybrid fiber concrete is proposed. The test data are obtained by adding steel tubes to increase the stiffness of the press, and the constitutive relationship of C40 hybrid fiber concrete is proposed. The constitutive relationship is polynomial in the rising section and rational in the falling section.
Investigation on tensile deformation and failure for 5052 aluminum alloy based on continuum damage model
Authors: Zhao Pengjing , Jiao Jingpin , Fang Gang , Chen Zhanghua , Gao Xiang
Published: November 2021

A VUMAT user material subroutine for the Lemaitre continuous damage mechanics model was developed based on the finite element solver ABAQUS/Explicit platform to investigate the deformation and failure behavior of 5052 aluminum alloy. The mechanical property parameters and damage parameters of 5052 aluminum alloy were identified by the inversion method combining tensile test and finite element simulation. The numerical simulation results showed that the force-displacement curves predicted by the established damage model were in good agreement with the experimental measurement, and the fracture location was close to the experimental results, which verified the accuracy and effectiveness of the damage parameters. The growth and distribution law of damage variable could be intuitively represented by the simulation results by the Lemaitre damage model.
A massively scalable Time-to-Digital Converter with a PLL-free calibration system in a commercial 130 nm process
Authors: Martinelli F. , Valerio P. , Cardarelli R. , Charbon E. , Iacobucci G. , Nessi M. , Paolozzi L.
Published: November 2021

A 33.6 ps LSB Time-to-Digital converter was designed in 130 nm BiCMOS technology. The core of the converter is a differential
9-stage ring oscillator, based on a multi-path architecture. A novel
version of this design is proposed, along with an analytical model
of linearity. The model allowed us to understand the source of the
performance superiority (in terms of linearity) of our design and to
predict further improvements. The oscillator is integrated in a
event-by-event self-calibration system that allows avoiding any
PLL-based synchronization. For this reason and for the compactness
and simplicity of the architecture, the proposed TDC is suitable for
applications in which a large number of converters and a massive
parallelization are required such as High-Energy Physics and medical
imaging detector systems. A test chip for the TDC has been
fabricated and tested. The TDC shows a DNL≤1.3 LSB, an
INL≤2 LSB and a single-shot precision of 19.5 ps (0.58
LSB). The chip dissipates a power of 5.4 mW overall.
Analytical results for the distribution of cover times of random walks on random regular graphs
Authors: Tishby Ido , Biham Ofer , Katzav Eytan
Published: November 2021

We present analytical results for the distribution of cover times of random walks (RWs) on random regular graphs consisting of N nodes of degree c (c ⩾ 3). Starting from a random initial node at time t = 1, at each time step t ⩾ 2 an RW hops into a random neighbor of its previous node. In some of the time steps the RW may visit a new, yet-unvisited node, while in other time steps it may revisit a node that has already been visited before. The cover time T
C is the number of time steps required for the RW to visit every single node in the network at least once. We derive a master equation for the distribution P

t
(S = s) of the number of distinct nodes s visited by an RW up to time t and solve it analytically. Inserting s = N we obtain the cumulative distribution of cover times, namely the probability P(T
C ⩽ t) = P

t
(S = N) that up to time t an RW will visit all the N nodes in the network. Taking the large network limit, we show that P(T
C ⩽ t) converges to a Gumbel distribution. We calculate the distribution of partial cover (PC) times P(T
PC,k
= t), which is the probability that at time t an RW will complete visiting k distinct nodes. We also calculate the distribution of random cover (RC) times P(T
RC,k
= t), which is the probability that at time t an RW will complete visiting all the nodes in a subgraph of k randomly pre-selected nodes at least once. The analytical results for the distributions of cover times are found to be in very good agreement with the results obtained from computer simulations.
The Use of Machine Learning for Accessing Landslide Susceptibility Class: Study Case of Kecamatan Pacet, Kabupaten Mojokerto
Authors: Irawan Listyo Yudha , Sumarmi  , Bachri Syamsul , Panoto Damar , Nabila  , Pradana Irfan Helmi , Faizal Rahmad , Devy Melinda Meganagatha Rosbella , Prasetyo Widodo Eko
Published: November 2021

Kecamatan Pacet, Kabupaten Mojokerto is one of an area with many landslide events in East Java Province. As a mitigation effort, this research aimed to map the landslide susceptibility class distribution of the research area. This research applied a machine learning analysis technic which combined Frequency Ratio (FR) and Logistic Regression (LR) models to assess the landslide susceptibility class distribution. FR bivariate analysis is used to normalized the data and to identify the influence significancy on each class of triggering factors. LR multivariate analysis is applied to generate the landslide probability (susceptibility) and to show the influence significancy of each triggering factor to landslide events. There are 12 triggering factors to landslide used in this research, which is: TPI, TWI, SPI, slope, aspect, elevation, profile curvature, distance to drainage, geological unit, rainfall, land use, and distance to the road. This research has 383 landslides and 383 non-landslide events as the data sample based on field survey, BPBD Kabupaten Mojokerto, and Google Earth Pro imagery interpretation. The proportion of dataset training and testing is 70% and 30%, which generated from the data inventory. This research used ROC analysis to validate the landslide susceptibility model. The result showed that the landslide susceptibility model has an AUC value of 0.91, which indicated that the model has high accuracy.
Rethinking local genius of the Merapi’s community in eruption disaster risk reduction. Does it still work?
Authors: Jamaludin S , Ashari A , Saputro E P N
Published: November 2021

Merapi Volcano in Central Java which has a high level of activity still holds hazard potential in the future. To reduce the disaster risks, a good disaster management is required. People who live in hazardous areas possess important social capital to enhance disaster management, in the form of local genius to cope with eruption. However, a question arises whether local genius still exists and is accepted by members of the younger generation. This paper presents a discussion about the existence of local genius on the younger generation in the southwest region of Merapi Volcano. The data were collected using some techniques which include interviews, focus group discussions, and literature study. The data were analyzed descriptively supported with scoring and statistical analysis. The results of the study show that local genius is not widely recognized and understood by the younger generation. There are no differences on the understanding of local genius among young members of the society who differ in age. The lack of teaching about local genius between generations causes a low understanding of young generation on local genius. Despite having a high motivation for preserving local genius, the younger generation perceive the local genius as a socio-cultural assets rather than as a source which enhances a disaster management. Overall, this paper presents new insights to understand the existence of local genius among the younger generation.