bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Cutting Method for Face-Hobbed Spiral Bevel Gears Based on Tool Path Modification
Authors: Li Lingzhi , Guo Wenchao , Yang Huawei , Mao Shimin
Published: February 2022

A novel tooth surface design method of face-hobbed spiral bevel gears is proposed, which utilizes a solid cutter without axis tilting through tool path control combining with optimized cutter blade profile to control tooth contact patterns and realize tooth lengthwise chamfering. Firstly, a gear tooth surface generating plan of tool path controlling actively is developed, the mathematical model of the tool path is built, and the equations are given in detail, the determination method of all control parameters is also described. Next, the tooth surface functions of generating gear and machined gear are established based on a mathematic model of the traditional cradle machine tool. Then, the machine setting is also given in concise equations. Finally, the tooth contact analysis is also conducted for a specific gear pair to validate the validity and the reasonability of the new tooth modification method.
Simulation Analysis of Cylinder Winding Prestress Based on Ansys
Authors: Li Jiaqing , Zheng Dayu , ChaoDong  , Zhang Zhen , Wang Feng , Wang Yongmei , Wang Xigui
Published: February 2022

Based on the distribution and layer characteristics of the prestressed steel wire-wound cylinder of the four-column hydraulic press, its supporting parts not only bear the constant stress caused by internal pressure, but also withstand the alternating stress caused by the steel wire-wound cylinder, and then produce gradual accumulation of plastic deformation. This paper uses theoretical calculation formulas to solve the corresponding parameters, establish a three-dimensional constitutive model, uses Ansys workbench to optimize its thermo-solid coupling simulation, and compares with the theoretical calculation results to verify the rationality of the design of the prestressed winding cylinder with cooling loading. The design of prestressed steel wire winding cylinder of 400MN plate hydraulic press is combined. Setting cylinder rated working pressure of 88MPa,an inner diameter of 1500mm,its wire winding layers are divided into 10,8,6,4 and 2.Based on the comprehensive analysis of the simulation results, the optimum initial stress table number of steel wire winding is obtained. According to the optimum initial stress table number, the influence law of preload coefficient on the design parameters of prestressed steel wire winding cylinder block is analyzed.
Enhancement of Radiative Cooling Effect by Bioinspired Hollow-core Triangular Structures
Authors: Li Ke , Zhang Tianshun , Pan Lei , Zhang Xinyuan , Xu Xiudong , Dou Shuliang , Li Yao , Zhan Yaohui
Published: February 2022

Inspired by the curiousness that what happens if the silver ant’s hair is designed to be hollow-core rather than solid-core while maintaining its triangular shape, the thermoregulatory response of both the solid- and hollow-core schemes are investigated comprehensively in a photothermal viewpoint. Optical responses, power balances, and field distributions collectively show that the hollow-core system has many advantages over the solid-core system in terms of selective reflection, omnidirectional absorption capability, and overall cooling performance. The investigation sheds more light on the physics in the hollow-core structures and suggests an alternative biomimetic scheme for thermal management.
Identification of Geometrical Error on Multi-Axis Machine Tools Based on a Laser Tracker
Authors: Liu Junfeng , Zhao Yuqian , Lai Tao , Li Fei , Liu Kexian
Published: February 2022

The geometrical errors are affected by many factors for a multi-axis machine tool, such as materials, manufacturing, assembly, measurement, control, and environmental. The geometric error will eventually be reflected in the accuracy of the workpiece; therefore, for each part of the machine tool, the measurement of geometric error is essential. Most geometrical errors are measured separately for each axis. The single geometrical error measurement method is time-consuming. The multiple geometric error measurement methods have some limitations based on different instruments. Laser tracker based on GPS (Global Positioning System) positioning principle can measure the dimensional coordinate. Thus, the laser tracker measured geometric errors in high efficiency, high precision, wide range. This paper introduces the method of measuring the multi-axis machine geometrical error by using a laser tracker with a 1280mm×1280mm×240mm range and compares the measurement result from the traditional method. The results show the laser tracker method has high measurement accuracy, and rapid measurement and compensation of geometrical errors are achievable on a large-stroke machine tools.
Application Research of Portable On-line Inspection System for Car Lights
Authors: Pan Mingqing , Deng Liang , Liu Qiupeng , Xue Mengping
Published: February 2022

In this article, a portable automotive lighting online detection system is designed, which can test various signals of car lamps online. It also can perform function and performance tests on multiple car lamps at the same time. The system has a compact structure in order to be easy to carry. It can be tested in the car light laboratory or be used for on-line testing of the production line. The system can automatically complete data collection and processing online. It can discriminate test results and print test reports easily. It has strong versatility and high measurement accuracy. This portable online detection system is convenient for detection and has good application value.
Research on the Synchronization Problem in the Combustion of Candles
Authors: Cheng Desheng , Shi Bo , Wang Shenghao , Huang Lingling , Qiu Guohao
Published: February 2022

In 2020, IYPT question 5 “synchronized candles” describes an interesting common phenomenon in life. The so-called synchronous candle refers to the flame that can be observed to oscillate when several adjacent candles are burning. Two such oscillations can be coupled with each other, leading to in-phase or reverse phase. In this paper, the control variable method is used to study the reason of the oscillation of a single oscillator and the phenomenon of inphase or anti phase oscillation of candles with different separation distance. It is found that the phenomenon of the oscillation coupling of regular candles is related to the distance between candles. Considering that the gas diffusion coefficient of the air is too low and the isotherm of the candle is relatively stable, the most likely cause of synchronization or inverse synchronization is thermal radiation. Finally, FDS software is used to simulate the combustion of the flame, and the results of in-phase and inverse vibration are also obtained.
Five-axis Ultrasonic Thickness Measurement of Hollow Blade Wall and Evaluation of Internal Chamber Section
Authors: Zhu Jiang , Zhang Wenze , Shen Yijun , Zhu Limin , Zhang Yang
Published: February 2022

Hollow blades play an important role in the aircraft engines. To ensure the manufacturing quality of the hollow blades, an ultrasonic inspection method for inspecting the internal chamber is proposed in this paper. The measured data is obtained by a five-axis Coordinate Measuring Machine with an ultrasonic probe. To fill the vacancy of data in high-curvature regions, an approximation curve is constructed according to the theoretical section line and the measured points. By adjusting the position of the theoretical clamber point and setting the adjustment direction, the non-uniform shrinkage of the ceramic core is simulated and the calculation amount is reduced. Filling points are obtained from the approximation curve and the internal chamber section is reconstructed by these points. The internal chamber of the hollow blade is evaluated from the two aspects of line profile and wall thickness. The experiments have verified the effectiveness of the proposed method.
Study on the Pretreatment of COD in Brewing Wastewater Based on the Ozone Oxidation Technology
Authors: Guo Ju , Hu Guangsheng
Published: February 2022

The high content of COD has always been a difficult problem for the efficient treatment of brewing wastewater. Pretreatment of brewing wastewater to reduce the content of COD was considered as a better solution. In this paper, ozone oxidation technology was used to pretreat brewing wastewater to preliminarily reduce the COD content, so as to provide beneficial conditions for further efficient treatment. The results showed that the reaction temperature (A), ozone intake (B), pH value of reaction solution (C) and reaction time (D) were the main factors affecting the removal of COD from brewing wastewater by ozone oxidation. Combined with the orthogonal test method, the optimum process conditions were A2B3C2D2. It was that the reaction temperature was 50 °C, the ozone intake flow was 7 L/min, the pH value of reaction solution was 7 and the reaction time was 1 h, which made the removal rate of COD reach 40.5%, and realized the goal of pre-removal of COD in brewing wastewater.
Study on Installation of Runway Status Lights
Authors: Jiang Li , Wen Hong , Dai Dongmei , Yan Shan , Yang Hao , Wang Yi
Published: February 2022

Runway Status Lights (RWSL) System uses light to send information to aircraft pilots and vehicle drivers to enhance their situational awareness, so installation and layout of runway status lights are of crucial importance. Based on the common configuration of the runways/taxiways of the domestic airports, we analyze the requirements imposed by the applicable standards on classification and installation of runway status lights and, on the basis of facts, select the optimal strategy for practical installation in Runway Status Lights System Verification Project implemented at Shanghai Hongqiao Airport. Actual testing indicates that lights can effectively send information from the view of pilots. The above analysis and study indicate that a runway status lights system with rationally arranged lights is able to inform aircraft pilots and vehicle drivers of runway safety status and plays a positive role in preventing runway intrusion incidents.
The Acoustic Emission Source Localization in the Pipeline Network with consideration of Radial Position of Defect
Authors: Li Hongyu , Geng Lei , Zhang Lu , Shi Yajun
Published: February 2022

Pipeline as one important mode of transportation, its safety is a very critical public concern. the acoustic emission (AE) played a very important role in pipeline safety inspection and monitoring due to its Many advantages. Moreover, AE is capable of localizing the defects in complex geometry in a real time, which is one of the most significant merits of this technique. For the localization algorithm, the 1D or 2D localization is most commonly used in AE measurement. The pipeline has been simplified as “axial line” without consideration of radial direction; however, in large-diameter pipelines, if the radial or circumferential direction across the certain position was ignored, it can cause the negative impact on the accuracy of the AE localization of pipeline defects. Therefore, this study explores the influence of radial position of the defects associated with the pipeline diameter on AE localization. Six typical pipe schedules were selected and modelled by COMSOL Multiphysics5.5 software. the tone burst wave and pencil lead break was used as the artificial AE source. The numerical model has been validated experimentally. By parametric study, it has been concluded that with the increase of diameter, the wave propagation path cannot be simply considered as the straight line anymore. Otherwise, the error of the localization will increase. Therefore, it is necessary to consider the influence of the radial position and real path of wave propagation for the precise localization of the defects in the large diameter-pipeline.
An Approach to Calculate Inverse of LR-Trapezoidal Fuzzy Matrix
Authors: Zhuo Quanxiu , Guo Xiaobin
Published: February 2022

In this paper, we devised a numerical algorithm for calculating the inverse of trapezoidal fuzzy numbers matrix. By analysing the existence of fuzzy inverse, the sufficient conditions are restricted. Furthermore, through calculating the approximate fuzzy inverse, the algorithm can be widely used in solving fully fuzzy linear system and it is validated by some given examples.
Metamaterials Design Method based on Deep learning Database
Authors: Zhou Xiaoshu , Xiao Qide , Wang Han
Published: February 2022

In recent years, deep learning has risen to the forefront of many fields, overcoming challenges previously considered difficult to solve by traditional methods. In the field of metamaterials, there are significant challenges in the design and optimization of metamaterials, including the need for a large number of labeled data sets and one-to-many mapping when solving inverse problems. Here, we will use deep learning methods to build a metamaterial database to achieve rapid design and analysis methods of metamaterials. These technologies have significantly improved the feasibility of more complex metamaterial designs and provided new metamaterial design and analysis ideas.
Design of Heartbeat Monitoring Based on Serial Port and its Implementation in QNX
Authors: Li Xukan
Published: February 2022

Today, with the rapid development of information technology, the stability of information systems is the guarantee for the normal operation of business systems and data security. Heartbeat monitoring technology enables high system availability and a high degree of system security at a lower cost. In order to ensure the stability of the information system, the heartbeat monitoring technology has been studied. Firstly, the principle of heartbeat monitoring technology is discussed. The basic heartbeat monitoring method is implemented between the main system and the standby system or any two connected systems through the serial port. Then the QNX is used as the technology to implement the carrier to RS-232-C. Finally, for the related modules such as heartbeat sending, heartbeat receiving and processing, the program working flow chart is presented, some examples are given, and interfaces are reserved for function expansion for reference by relevant engineering and technical personnel. In practical applications, based on the actual situation, emergency procedures and recovery procedures can be designed to improve the emergency response capability and reliability of the overall system.
Demand-side Response User Selection Based on Improved BPSO
Authors: Chen Jun , Bu Feifei , Wang Yuanyuan , Bai Hongkun , Hua Yuanpeng , Han Ding , Sun Yi
Published: February 2022

In order to use the demand-side response activities to stabilize the peak load, ensure the balance of power supply and demand, and promote the quality and efficiency of the power grid, this paper constructs the demand-side response user competition models in different stages. The improved BPSO algorithm is used to optimize the subsidy cost weighted model in the saturated user competition model, and the algorithm is implemented automatically based on the blockchain intelligent contract. Simulation and experimental results show that, compared with other user selection schemes, these models can improve the actual user response and reduce the subsidy cost of the demand response centre. It can be seen that in the case of saturated user competition, the improved BPSO algorithm is feasible in the application of demand-side response to user selection and optimization of demand-side management.
Study on Personnel Detection Based on Retinex and YOLOv4 in Building Fire
Authors: Li Wei , Li Sen , Wang Yeheng , Yun Junying
Published: February 2022

When a fire occurs in a building, the internal environment is full of dense smoke, which will greatly hinder the evacuation and rescue of the trapped persons. If the evacuation and rescue are not in time, the life safety of the trapped persons will be seriously threatened. In response to this problem, this paper proposes a method for quickly detecting trapped persons in building fires. This method uses a combination of multi-scale Retinex image sharpening algorithm and YOLOv4 person detection algorithm. First obtain the image information of the fire scene, use the multi-scale Retinex algorithm based on the Gaussian pyramid to perform the sharpening process, and then use the YOLOv4 model to perform the personnel detection on the sharpened fire scene image. The experimental results show that the confidence of image person detection after Retinex sharpening processing has been significantly improved.
Efficient Local Level Set Algorithm Combined with Bidirectional Evolutionary Criterion Using Discrete Variables and its Appliance to Topology and Shape Optimization
Authors: Zhang Wenhui , Liu Jing , Xia Zhenhua , Zhang Yaoting , Yu Niuben
Published: February 2022

Many level set methods (LSMs) have been used for topology and shape optimization. An efficient topology optimization algorithm is proposed by combining a new bi-directional evolutionary criterion (BEC) with the local LSM (LLSM). The BEC is established using multiple discrete variables (DVs) and introduced into the bi-directional evolutionary structural optimization (BESO) method so that the DV-BESO method obtained can be applied to topology optimization. The LLSM is used instead of the global LSM due to its high efficiency. In the LLSM, the computational efficiency can be further improved by solving a distance regularized equation without the re-initialization procedure. Two benchmarks show the high efficiency of this proposed combined algorithm for topology and shape optimization.
Simulation of Automatic Conveying System for Steel Frame of Bridge Box Girder
Authors: Yu Fuhua , Bian Xuhui , Shen Jiandong , Yue Qi , Zhang Ying
Published: February 2022

Aiming at the inefficiency of processing steel frame of the bridge box girder, to improve the automation degree of the production process, the intelligent manufacturing is applied to the automatic conveying system. The configuration control technology is used to simulate the automatic conveying system for the steel frame of bridge box girder. The control layer based on the PLC and the monitoring layer based on the WinCC communicates through TCP-IP protocol. The monitoring layer includes screen configuration, data monitoring, alarm designing, and other functions. Through the system coordination, the simulation of the automatic conveying system for the steel frame of the bridge box girder is carried out.
Development of New Energy Vehicle Teaching System Based on Mixed Reality Technology
Authors: Wu Huibo , Lan Tianwen , Wang Xiaohua
Published: February 2022

There are many high-pressure parts in new energy vehicles, and the structure of the vehicle is basically closed. These bring great trouble to the training and learning of new energy vehicles. With the rapid development of mixed reality and computer control technology, virtual reality teaching technology emerges at the historic moment. But the current system needs to be improved in performance, especially in the combination of virtual and real. This paper developed a new energy vehicle teaching system based on virtual mixed reality (MR) technology. In the system, there are system hardware basics, basic layer, management, system application layer, professional application layer and so on. The system achieves the effect of combining the virtual and the real, and operates the virtual model by Gesture movement. This system is very convenient and practical. Users can teach and train the structure and working principle of new energy vehicle parts, by operating the new energy vehicle model in this system.
Feasibility Analysis of Dispersion Curves in Calculating Equivalent Parameters of Honeycomb Pentamode Metamaterials
Authors: Luo Ziyin , Zhou Qizheng , Guo Peng
Published: February 2022

Honeycomb material is one of the basic structures of two-dimensional pentamode materials. Dispersion curve, as a common method for analyzing crystal properties, is widely used in the study of pentamode materials. It is necessary to study the probability that using dispersion curves to calculate the equivalent parameters of honeycomb materials. In this paper, compared with the improved Gibson formula, the accuracy of the equivalent parameters calculated by dispersion curves of honeycomb pentamode materials with different structures is studied. The study found that the calculation error of dispersion curve for the homogeneous material equivalent parameters is lower than 1%; The error for anisopathic honeycomb pentamode materials is 10% to 20%, and it decreases with the ratio of wall thickness to edge length; Calculating anisotropic honeycomb pentamode material equivalent parameters by dispersion curves is inapplicable. But dispersion curves can be used to predict the degree of anisotropy of honeycomb materials, such as the ratio of volume modulus in the X and Y directions, with less than 5% errors.
Study on Seismic Risk Exposure and Vulnerability of Buildings in Southwest China Based on AI Technology
Authors: Li Changlong , Lyu Hongshan
Published: February 2022

In this paper, we made building taxonomy for Southeastern Tibet in Southwest China and attempted to apply the 3D image pattern recognition technology in UAV aerial image processing and pattern recognition, for the statistics of building types and numbers, and explore more applications of AI technology in geoscience research. We compared our vulnerability models with parts of vulnerability models of buildings in Nepal in the research of Nepal’s seismic hazard and risk assessment. The comparison between our vulnerability models and Nepal ones shows that public and private houses have better seismic resistance than the houses in Nepal.
Green Building Energy Efficiency Evaluation and Optimization
Authors: Wang Weilai , Hu Zhi
Published: February 2022

This paper analyzes the influencing factors of energy saving benefits of green buildings, and summarizes six types of influencing factors of energy saving benefits, including lighting performance and ventilation performance. Through Bayesian network machine learning, the Bayesian network evaluation model of green building energy efficiency is constructed, and the comprehensive evaluation index system of green building energy efficiency is established. Combined with practical case analysis, the core influencing factors with high degree of influence are obtained by Bayesian network reasoning.
Review on Research Progress of MICP Technology
Authors: Cui Meng , Xiong Huihui , Lü Suying
Published: February 2022

MICP technology is a new technology proposed for soil reinforcement research in recent years, which has the advantages of environmental protection and sustainability. Through the review and analysis of domestic and foreign literature, the mechanism of microbial mineralization reaction and the research progress of domestic and foreign scholars were comprehensively summarized. This paper introduces the basic principle of urea hydrolysis in MICP technology, and expounds the control factors of microbial mineralization experiment and the practical application of this technology in engineering. Finally, the future development prospect of MICP technology is forecasted.
A Practical Study of Green Building Energy Efficiency Solutions for Public Building Projects
Authors: Song Yiwen , Chang Cheng
Published: February 2022

Under the background of ecological civilization construction, this article aims at the Qingdao Shooting Sports Center project, with the specific technical scheme, and energy consumption calculation adopted in green construction and energy saving. Combining the theoretical knowledge of green buildings with actual projects, through the energy-saving assessment of the project, the type and quantity of energy consumption of the project are grasped, the energy consumption level of the project is analyzed, and the rationality of the energy utilization of the project and the feasibility of energy-saving measures are evaluated. This article provides some reference data and research for preparing the green and energy-saving design and evaluation report of public building projects.
Experimental Study on the Strength of Coal Gangue Aggregate Concrete with Basalt Fiber
Authors: Yang Guowei , Zha Wenhua
Published: February 2022

In order to study the effect of basalt fiber content, basalt fiber length and coal gangue activation on compressive strength and splitting tensile strength of concrete, 24 groups of orthogonal experiments were designed. The results show that the influence of various factors on the compressive strength and splitting tensile strength of concrete is coal gangue activation > basalt fiber content > basalt fiber length. The activation of coal gangue is conducive to the increase of concrete strength; the influence of fiber content on strength increases first and then decreases; the increase of fiber length is beneficial to compressive strength and unfavorable to splitting tensile strength; the best ratio of engineering practice is fiber content 0.10 %, fiber length 18 mm, activated coal gangue.
Experimental Study on Vibration Absorption Performance of Floating Slabs of Vibration Isolation Pads in Metro Shield Tunnels
Authors: Peng Guangzhao , Fu Kun , Zhang Fengdong , Bai Jian , Zeng Zhiping , Li Zhuang , Yin Huatuo , Huang Zhibin , Tang Qihui
Published: February 2022

The monolithic track bed with isolated damping pad and floating slab is a common design of urban subways in recent years.The type of track bed, urban subway lines usually pass through densely populated areas of the city, and subway trains.In the course of driving, it is inevitable that large track vibration noise will be produced. In order to reduce the impact of track vibration noise on the daily life of surrounding residents, noise reduction measures must be considered during track design. Isolated shock absorber floating board The monolithic track bed is one of them. Compared with the steel spring floating slab monolithic track bed, it has the technical characteristics of “low engineering cost, more convenient construction, and good noise reduction effect”. In order to study its damping effect, we selected two working conditions of straight line and curve for comparison. It can be seen from the comparison results with the ordinary track bed: (1) The acceleration level of the shock-absorbing cushion tunnel wall in the straight section is greater than the ordinary track bed section within 1∼10Hz, and is close to the ordinary track bed section within 12.5∼20Hz, at 25 It is smaller than the section of ordinary track bed within ∼1000Hz. (2) The maximum Z-vibration level measured from the tunnel wall is most suitable for evaluating the seismic source intensity of the subway, and the seismic source intensity of the subway line is 65.69 dB.
Simulation Analysis and Application of Super High-rise Tower Construction Process
Authors: Ou Yazhou , Chen Bao , Jia Hongxue , Yin Guanghua , Cao Jiang
Published: February 2022

Wenzhou Lucheng Square Phase IV project, whose main tower reaching 378.8m high, belongs to the super high-rise building structure. Considering the influence of shrinkage and creep characteristics of concrete on vertical deformation differences of components, Midas Gen was used to simulate and analyze the whole construction process of the main tower. The analysis results of different working conditions are compared, the rationality of the construction scheme is checked and a general conclusion is drawn.
Study on Treatment Technology of Rock Slope Landslide of an Expressway in Guizhou
Authors: Xiao Yuanlun , Li Shengting
Published: February 2022

A highway deep cutting slope is in Guizhou province, with a total length of about 258m and a maximum excavation height of 49.96m. after continuous heavy rainfall, groundwater seeped out on the slope, and cracks appeared. Based on calculation and engineering experience, the slope was reinforced by anchor ropes and anti-slide piles. After the treatment, the deformation of the slope was monitored by GNSS displacement monitors, and the results of displacement monitoring show that the three monitoring points No.1, No.2 and No.3 are relatively stable, and the daily accumulated horizontal displacement of monitoring point No.4 is relatively large, reaching 400mm on March 17th, but the change rate of displacement tends to slow down gradually.
Numerical Analyses of Liquid-Core Fiber Optic SPR Sensor with Nano-Porous Sio2 as Inner Coating
Authors: Meng Jinwei , Luo Wei , Yi Duo , Li Xuejin , Hong Xueming
Published: February 2022

In this paper, a novel type of liquid-core fiber optic SPR sensor with a nano-porous SiO2 inner coating is proposed. The nano-porous SiO2 is deposited on the inner wall of the quartz tube. Due to the flexible and adjustable refractive index of the deposited material, the RI detection range of the sensor is expanded. The simulation results show that the proposed sensor owns good responses in both low and high refractive index regions, with the corresponding RI sensitivities of 1043.71 nm/RIU and 1234.86 nm/RIU respectively, while the FWHM is only about 20 nm. There are some potential applications for the proposed sensor in environmental monitoring, biochemical detection, food safety etc.
UAV Base Station Site Selection Based on Spiral Algorithm in Complex Environment
Authors: Bian Qiang , Xu Donghui , Kang Kai , Liu Jiangliang
Published: February 2022

The Wireless broadband communication system is the wireless communication hub and the main means of communication under the background of actual combat.In complex environments such as terrain impact and external interference strikes, the on-board base station of wireless broadband communication system may not work properly. As an air base station, UAV ensures the continuity and reliability of communication.Aiming at the problem of UAV base station location in complex environment, this paper proposes a UAV base station location method based on spiral algorithm.Firstly, this paper establishes the air-to-ground propagation model based on the characteristics of the actual geographical environment.Secondly, the coverage capability of the UAV base station is obtained by link budget and the optimal height analysis of the UAV.Finally, the location planning of the U AV base station is completed by the spiral algorithm. The simulation results show that the spiral algorithm needs fewer UAV base stations than the k-means algorithm, which can reduce the cost of the network. The method proposed in this paper can select the appropriate site for the base station of the UAV under the complex environment.
An Event Analysis of Circuit Breaker Tripping Under Equipotential Operation Mode
Authors: Zhang Qionghua , Long Quanyu
Published: February 2022

Under the special operation mode of bypass generation equipotential supply, the equipment joint just repaired and treated forms a small impedance due to excessive antifouling and anti-oxidant. Because both ends of the impedance are equipotential, it cannot be broken down, resulting in the tripping event of standby protection action of the equal bypass circuit breaker.
An Infrared Image Based Asphalt Temperature Separation Evaluation Model
Authors: Li Jun , Peng Ting , Cheng Long , Wang Xiaoling
Published: February 2022

This article points out the shortcomings of the NACT assessment index based on infrared images. In order to develop a new method for evaluating temperature separation, this article proposes two influencing factors, namely, a different temperature interval and a low temperature zone based on NACT temperature difference. For the temperature interval, three kinds of asphalt mixtures, AC-13, AC-16 and AC-20, are used to study the change of void ratio at different molding temperatures and obtain the temperature separation evaluation method based on the difference of void ratio in the internal test and obtain the TIC (Temperature Influence Coefficient) for different temperature intervals by conversion; for the low temperature zone, the influence coefficient δ for the low temperature zone is obtained by simulation analysis. By combining TIC and δ, TSSI (Temperature Separation Status Index) is obtained.
Mechanical properties characterization of Ti6Al4V for artificial hip joint materials prepared by investment casting
Authors: Ismail R , Bayuseno A P , Fitriyana D F , Taqriban R B , Muhamadin R C , Al Hakim R A N , Siregar J P
Published: February 2022

The Investment Casting (IC) process is a type of casting that can produce the suitable shape and size of components by minimizing porosity and defects. However, research on ICs for the manufacture of artificial hip joints made from Ti6Al4V is still lacking. Therefore, the purpose of this study is to determine the mechanical properties of an artificial hip joint made from Ti6Al4V casted using the investment casting method. The stages of the investment casting process used in this research are wax injection, ejection of wax pattern, tree assembly, slurry coating, final sand mould, dewaxing, preheating, pouring, and final product. The characterization of IC products was carried out by tensile test, hardness test, and impact test. The yield strength, Ultimate Tensile Strength, Elongation (%), Hardness (HRC) and Impact Strength obtained in this study were 636 MPa, 687 MPa, 17%, 29 HRC, and 5.3 J, respectively. The lower oxygen content in Ti Alloy after IC resulted in a decrease in yield strength, ultimate tensile strength, hardness, and impact energy. However, the low oxygen content in Ti Alloy after IC resulted in increased ductility (% elongation).
Differences in preferences, water content, and dietary fibre of jackfruit seed crackers enriched with red beetroot (Beta vulgaris)
Authors: Astuti P , Zumar H A , Fathonah S , Ansori M
Published: February 2022

Increasing public attractiveness to crackers can be done by diversifying non-protein cracker products. Jackfruit seeds have potential as an additive for crackers because it contains high starch and nutrients, such as dietary fibre. The purpose of this research is to determine the differences in preference for experimental crackers as well as water content and total dietary fibre. Mean analysis was used to determine level of public preference and Kruskal-Wallis test is used to determine differences in the level of preference. To determine the difference in water content and dietary fibre, used non-homogeneous sample t-test. Preference test showed steamed and boiled-steamed jackfruit seeds treatment got an average score of 5.6 and 5.7 criteria favoured by panellist, treatment for boiled jackfruit seeds with average score of 5.4 criteria less favoured by panellist. The nutritional analysis with low water content and high dietary fibre in steamed treatment with average water content of 2.40% and total dietary fibre of 9.21. Kruskal-Wallis test showed P-value of 0.000 <0.05, meaning that there was a difference treatment of jackfruit seeds on texture preference aspect. Non-homogeneous sample t-test analysis showed P-value <0.05, meaning that there was a difference in water content and dietary fibre.
Design and production of multifunctional food oven with energy-saving gas fuel
Authors: Sumbodo W , Kriswanto  , Setiyawan A , Pamiyanto J , Hadikawuryan D H , Widodo R D , Jamari J
Published: February 2022

Ovens sold in the market have many features that make them easier to use but are not suitable for the needs of Small and Micro Enterprises (SME), namely large capacity, multifunction, use of gas fuel, energy-saving, and ease to operate. It is necessary to design and manufacture an oven according to the needs of SME users. The purpose of this study is to design, build, assess the feasibility, and evaluate the operating energy usage of the oven. The oven design process uses the French’s model and Quality function deployment (QFD) methods. Experiments to test the oven’s feasibility. The study’s result is that oven design validated user requirements by design experts, manufacturing experts, and users (SMEs). The oven prototype has shown performance to reduce water content according to food products with a distribution permit in Indonesia. The energy consumption of oven prototype has been compared to an electric oven similar capacity that showed that there is an energy-saving of 6.8%. Based on validation of design and product feasibility and calculation of oven energy consumption, the oven meets the small and medium enterprises (SME) users’ needs.
Analysis and solutions of traffic shift on 4G networks in the campus environment during the Covid-19 pandemic
Authors: Salim N A , Sulistyawan V N , Intan F T
Published: February 2022

The monitoring and management of Internet data traffic is an important requirement to be used and interpreted as a resource to make informed network management decisions. At the time of the covid-19 pandemic there was significant internet traffic changed caused by most of the students who returned home because of home-based lecture policies. Earlier Internet traffic that was in offices, college areas, schools and public places was so high even tended to overload. However, at present Internet traffic shifts to residential or residential areas. However, currently internet traffic is shifting to this problem, the telecommunications operator to do optimization to reduce expenses due to decreased income in the area around the campus. Optimization is done by dynamic carrier shut down, one carrier will be turned off if its utilization is lower than a predetermined threshold.
Design and development of temporary immersion bioreactor system controlled by microcontroller
Authors: Woowong A , Piladaeng N
Published: February 2022

This research aims to develop, design and construct a temporary immersion bioreactor (TIB) controlled by microcontroller. The designed TIB can control the time for plant feeding and the carbon dioxide (CO2) concentration via application. The TIB consists of 2 sets of the plant tissue culture containers. The TIB can define the feeding and the CO2 concentration control times up to 10 and 4 time periods per day, respectively. The system feeds the plants and controls the CO2 concentration during the defined time periods. The test results of the feeding time control illustrated that the TIB could set the feeding times conveniently and quickly. Moreover, the system could properly work following the set times. For the test results of the CO2 concentration control, it was found that the TIB could control the CO2 concentration in the containers during the set operating time. It took about 7, 28, 30, 36 and 21 minutes after the system started working to adjust the CO2 concentration in order to be at the set levels of <750, 1,500, 2,000, 2,500 and 3,000 ppm, respectively. The CO2 concentration control system could properly work with error less than 10%.
Microwave heating control system using genetic algorithm-based PID controller
Authors: Apriaskar E , Prastiyanto D , Malik M A , Ramadhan A E , Destanto R , Abdullah@Idris H , Osman M K
Published: February 2022

The superiorities of microwave heating technology have attracted many researchers for further development. Designing a satisfying temperature control system for the microwave system is one of them. To confirm that the controller can work with good system performance, the adjustment of controller parameters is important. Most previous research about microwave control systems did not focus on the tuning problem which is presented in this work. This paper provides the use of a genetic algorithm to adjust the best parameters for a PID controller. A microwave heating system with a single microwave power input and a single output temperature probe which is identified using the ARX model is examined. Evaluation of the proposed controller was conducted in the simulation environment using MATLAB. The result shows that the genetic algorithm can obtain the most optimized parameter for PID controller which can follow a certain heating pattern. The parameters for Kp, Ki, and Kd are 998.94, 79.42, and 79.78, respectively. It can minimize the value of integral absolute error for the given setpoint to 446.11.
Application of the adaptive re-use concept in historical building (case study of cigarette factory Gunung Kedu and cigarette factory Gunung Kelapa enterprises residence)
Authors: Perbawa I R H , Handayani K N , Musyawaroh
Published: February 2022

Cigarette Factory Gunung Kedu and Cigarette Factory Gunung Kelapa are kretek industries owned by the Atmowidjojo family. This family has a big role in the economic progress of the Kudus Kulon community. This role can be seen in the large number of jobs provided for the surrounding community. Physical relics that are still intact to date are; Atmowidjojo’s house, Nadirun’s house, office, and Gunung Kedu factory. Buildings that have historical value are important elements in the development of the city area, as the identity and image of the city. However, at this time the awareness of the public and the government regarding the preservation of buildings is quite lacking. The phenomenon that occurs in the Kudus Kulon area at this time is that many historical buildings belonging to the community are sold and torn down. Sales and demolition of buildings due to the high cost of maintaining historic buildings. Based on this importance, it is necessary to apply the concept of adaptive reuse as a sustainable step in preserving buildings that have historical value in Kudus. The purpose of this research is to study the steps for the sustainability of the application of conservation in buildings that have a history, with building conditions that are still suitable for use. The method in this research uses descriptive qualitative using a case study approach.
Green campus development of UNNES postgraduate program: potential identification and performance analysis
Authors: Prihanto T , Hardati P , Santoso E B , Wibowo A A
Published: February 2022

Universitas Negeri Semarang (UNNES) with the vision of conservation-minded university with international reputation continues to develop a conservation-based academic life, namely the value of caring for the environment. This vision is supported by one of the internal UNNES Green Campus Programs, namely H-BAT (green, clean and healthy). Based on the results of the H-BAT assessment in period of June 202, it showed that the achievement of the UNNES Postgraduate Program (it’s called PPs UNNES) performance was 62.24%. This performance achievement is a low indicator for PPs UNNES in its efforts to develop a green campus. The formulation of the problem that can be raised is how to improve the performance of PPs UNNES’s H-BAT achievement in the field of conservation. The purpose of this study is to identify potential and analyse campus performance in accordance with the H-BAT indicator assessment criteria. The method used in this research is descriptive exploratory. The results show that the achievement of 62.24% of the H-BAT assessment illustrates that the PPs UNNES green campus governance is not optimal, both in administration, programs, policies and implementation in the field. PPs UNNES has great potential to be able to better improve H-BAT achievement, but it seems that there are obstacles that may be the cause of the low H-BAT performance achievements in the past period. It needs a lot of efforts to optimize the existing potential so that it can fulfil the H-BAT assessment indicators more optimally.
Molecular emission dynamics from a femtosecond filament induced plasma plume
Authors: K M Muhammed Shameem , P Madhusudhan , Das Rituparna , Bharadwaj Pranav , Vinitha Nimma , Soumyashree Swetapuspa , Kumar Kushawaha Rajesh
Published: February 2022

In this study, we investigated the filament-induced plasma properties and the associated molecular emission features from three different non-metallic samples. Graphite, polymethyl methacrylate, and Teflon samples have been ablated using a tightly focused filament, and their emission spectra were analyzed using a time-integrated optical emission spectroscopy technique. The temporal responses and evolution dynamics of molecular species such as CN and C2 from these samples in ambient conditions are compared. The tightly focused filament was generated by focusing the Ti:Sapphire femtosecond pulses having a pulse duration of 29 fs using a short focal length external focusing system. The time-integrated intensified charge-coupled device images of air filament show that the filament survives up to a few nanosecond time duration after the onset of air plasma. The influence of physical and chemical properties of the samples during filament ablation has also been studied by characterizing the optical emission spectra. We find that the molecular signal intensity strongly depends on the sample properties and the position of the sample in the filament. The increase in molecular emission intensity from a graphite sample as a function of incident laser intensity suggests that the tightly focused filament surpasses the intensity clamping value.
Investigating aperture-based approximations to model a focused dynamic collimation system for pencil beam scanning proton therapy
Authors: Nelson Nicholas P , Culberson Wesley S , Hyer Daniel E , Smith Blake R , Flynn Ryan T , Hill Patrick M
Published: February 2022

Purpose. The Dynamic Collimation System (DCS) is an energy layer-specific collimation device designed to reduce the lateral penumbra in pencil beam scanning proton therapy. The DCS consists of two pairs of nickel trimmers that rapidly and independently move and rotate to intercept the scanning proton beam and an integrated range shifter to treat targets less than 4 cm deep. This work examines the validity of a single aperture approximation to model the DCS, a commonly used approximation in commercial treatment planning systems, as well as higher-order aperture-based approximations for modeling DCS-collimated dose distributions. Methods. An experimentally validated TOPAS/Geant4-based Monte Carlo model of the DCS integrated with a beam model of the IBA pencil beam scanning dedicated nozzle was used to simulate DCS- and aperture-collimated 100 MeV beamlets and composite treatment plans. The DCS was represented by three different aperture approximations: a single aperture placed halfway between the upper and lower trimmer planes, two apertures located at the upper and lower trimmer planes, and four apertures, located at both the upstream and downstream faces of each pair of trimmers. Line profiles and three-dimensional regions of interest were used to evaluate the validity and limitations of the aperture approximations investigated. Results. For pencil beams without a range shifter, minimal differences were observed between the DCS and single aperture approximation. For range shifted beamlets, the single aperture approximation yielded wider penumbra widths (up to 18%) in the X-direction and sharper widths (up to 9.4%) in the Y-direction. For the example treatment plan, the root-mean-square errors (RMSEs) in an overall three-dimensional region of interest were 1.7%, 1.3%, and 1.7% for the single aperture, two aperture, and four aperture models, respectively. If the region of interest only encompasses the lateral edges outside of the target, the resulting RMSEs were 1.7%, 1.1%, and 0.5% single aperture, two aperture, and four aperture models, respectively. Conclusions. Monte Carlo simulations of the DCS demonstrated that a single aperture approximation is sufficient for modeling pristine fields at the Bragg depth while range shifted fields require a higher-order aperture approximation. For the treatment plan considered, the double aperture model performed the best overall, however, the four-aperture model most accurately modeled the lateral field edges at the expense of increased dose differences proximal to and within the target.