bluuebunny/crossref_metadata_2025 huggingface dataset:
Video reconstruction of generative adversarial network based on global perception
Authors: Shende Chen , Xiaoman Wang , Wenbo Jing
Published: June 2021

Aiming at the problem that the current video reconstruction can not take into account the high perception quality and high temporal correlation, a video reconstruction of generative adversarial network based on global perception is proposed. The generator adopts a recurrent and iterative network architecture. In order to make up for the lack of extraction of global information by the frame alignment network, the alignment network combines the global information extracted by the global information perception to perform frame alignment. Through the static temporal loss and the temporal statistics loss, combined with the relative discriminator of sequence frames input, the temporal correlation of the generated images sequence is improved. Experimental comparisons were performed on the Vid4 and REDS test sets, and the best image perception quality index (LPIPS/NIQE) were obtained, as well as better temporal correlation (tLPIPS), reaching 0.192/3.417/0.328 and 0.138/3.223/0.217. Experimental results show that the proposed method can effectively improve the perceptual quality of reconstructed video frames and has good temporal correlation.
Improved RRT-Connect Algorithm for Urban low-altitude UAV Route Planning
Authors: Jin Haonan , Cui Wei , Fu Huaye
Published: June 2021

Path length and computation time in path planning seriously affect the safety and efficiency of urban low-altitude UAV flight. This paper improves RRT-connect Algorithm for path planning, the search step length, parent node selection and branch orientation selection are optimized to reduce the path length and algorithm time. Starting from the shortest parent node of the two trees, track search is carried out in the Middle Direction, the search step length is changed according to the field of view, the search step length is cut down quickly through the open field, and the search step length in narrow space is reduced, at the same time, the growth direction of the main branch of the search tree is controlled by the angle to reduce the probability of the UAV turning sharply. Simulation experiments show that the proposed algorithm has better time and space advantages and convergence than the current popular algorithm, the comparison results show that the optimized Algorithm RRT-connect is superior to the current flow Algorithms RTT-extend and Lazy-RTT in terms of the time consumption of short-time fast search and the length of path generation.
Detail Reconstruction of 3D Face Model from Single Image
Authors: Xu Hongxin , Lan Ruoming , Li Tianping
Published: June 2021

With the development of computer vision technology, 3D face model reconstruction technology has a great breakthrough. In view of the current popular deep learning method, we use an algorithm based on neural network to restore the details of 3D face model. We design a high frequency detail generation network to generate displacement map based on the texture extracted from the original image. The displacement map contains a large number of high frequency detail features of the target face. By embedding the displacement map into the face model, the details of the model can be restored.
Aggregating Local Features of Convolutional Neural Network for Material Image Retrieval
Authors: Qing Qing
Published: June 2021

Large-scale microscopic images in materials science need to be indexed and managed using practical management tools. Content-based Image Retrieval (CBIR), which indexes and searches images based on the image features, allows for long-term data management in large-scale image datasets. Considering the difference between material microscopy images and natural ones, we propose a novel CBIR method for material microscopic images. In the proposed method, convolutional neural networks (CNN) are used to extract local features from an image, and the scale-invariant feature transform (SIFT) model is used to generate a keypoint density map (KDM). Experiments on a material microscopic image dataset show that the proposed method achieves an approving retrieval performance.
A Multi-view Image Sets Classification Based on Graph Convolutional Neural Network
Authors: Liu Xun , Chen XiaoLin , Xia GuoQing , Chen HuaZhen , Ye HeZhong , Chen ZhanChi
Published: June 2021

Multi-view images represent the target object from various perspectives. We propose a new spectral graph convolutional neural network (BSGCN) for multi-view image sets, which uses spectral graph convolution technology to process multi-view image sets. With the batch normalization techniques, the BSGCN speeds up the model convergence and improves the generalization capabilities of the model. We analyze the performance of two variants of BSGCN and its model by experiments on multi-view datasets. Experimental results show that the BSGCN is 2.84% and 7.26% higher than the classic graph CNN [17] on Modelnet10 and Modelnet40 multi-view datasets, respectively, and 0.34% higher than the classical CNN [6] on Modelnet40 multi-view dataset.
Research on a method of digital map generation for tracked equipment maneuvering on soft ground
Authors: Mingming Liu , Meiling Zhu , Yanxi Ren , Jingjun Yuan , Jibin Hu
Published: June 2021

The mobility of equipment refers to the ability of fast driving under various road, ground and terrain conditions that may be encountered in the tactical background. In recent years, with the rapid development of national defense and aerospace, tracked equipment is required to reach more and more areas. However, due to its low bearing capacity and low adhesion capacity, soft roads such as sandy land, swamp, farmland, tidal flat and lunar soil are easy to cause subsidence, resulting in low driving efficiency or even inability to drive, which seriously restricts the feasibility of driving equipment. In this paper, considering the characteristics of tracked equipment, through the superposition of multi-layer spatial information such as slope, aspect, soil and elevation data, based on equipment dynamics, fuzzy theory and ant colony algorithm, the generation of mobile digital map and mobile path planning of tracked equipment under soft road and complex terrain are studied, which has important practical significance.
Application of Electronic Technology in Automobile Safety System
Authors: Li Mengyin , Ge Xinye
Published: June 2021

This article analyzes the factors that affect the stability of the vehicle safety system. The research content of this article includes own factors, environmental factors, human factors. The author studies the specific application of electronic technology in the active safety processing, passive safety processing, and post-accident processing of automobile safety systems. The author analyzes the development of intelligent electronic technology, diversified development, energy-saving development and other trends. The purpose of this article is to give full play to the application value of electronic technology and improve the reliability of the operation process of the automobile safety system.
The influence of time-varying mesh stiffness on natural characteristics of planetary gear system
Authors: Zhang Keming , Zhou Tao , Shao Yimin , Wang Guochao
Published: June 2021

Modal property is the crucial factor that can influence the vibration characteristics of the planetary gear system. Previous studies used time invariant mesh stiffness (TIMS) to study the natural characteristics. However, with the rotation of the gear, the meshing stiffness will change periodically which will lead to changes of modal properties. Based on these properties which are ignored in previous studies, a translational-torsional free vibration model base on time-varying mesh stiffness (TVMS) rather than time invariant mesh stiffness (TIMS) is established in this paper to study the modal properties of the planetary gear system, the effects of TVMS on the natural characteristics are investigated. The results show that the meshing phase difference and the change regulation of the time varying natural frequencies are correlated, and there is a dramatic variation of higher order natural frequencies at the contact teeth change points. Furthermore, a useful conclusion can be drawn that takes TVMS to calculate higher order frequencies has certain advantages over traditional methods.
Research and Analysis on firing accuracy of Naval Gun
Authors: Liu Ziyu , Chen Weiyi
Published: June 2021

This paper expounds the significance and function of studying the firing accuracy of naval gun weapon system, and briefly analyzes the firing error source, firing accuracy evaluation and firing error compensation method of naval gun. Through the establishment of the analysis model of firing accuracy, the principle of error sources affecting firing accuracy is clarified. Taking the projectile tracking method as an example, different firing correction methods of naval gun are analyzed, so as to improve the firing accuracy of naval gun.
The design of eccentricity ratio, relative clearance and length-to-diameter ratio of water-lubricated journal bearings under different working conditions
Authors: Liu Ying , Gao Gengyuan , Yin Zhongwei , Jiang Dan , Ding Ning
Published: June 2021

This paper investigated the eccentricity ratio, relative clearance, and length to diameter ratio under different load carrying capacities and journal rotation speeds, aiming to provide design reference of eccentricity ratio, relative clearance, and length to diameter ratio in water-lubricated bearing design process. The computer fluid dynamics was adopted to analyze eccentricity ratio, relative clearance, and length to diameter ratio of water-lubricated bearing. The cavitation effect of water was considered in the analysis. The simulation results of eccentricity ratio were verified by experiments. In different journal rotation speeds, the relative clearance had little influence on the maximum water film pressure and load carrying capacity. The numerical number of maximum water film pressure and load carrying capacity was in a small range. Designing chart of eccentricity ratio, relative clearance, and length to diameter ratio was provided.
The Vehicle behavior under Braitenberg Vehicle 4 Driven by Gaussian-like function
Authors: Guo Shuyi , Xu Henghao , Wang Yuxuan
Published: June 2021

The goal of this paper is to recreate the Braitenberg vehicle 4 in Simulink via MATLAB. The attempt of using the Gaussian-like function to control the vehicles’ trajectory would result in the further analysis of the so-called behavior, which would then be classified into two types related to the term in the field of psychology “invasion” and “retraction”. The tool we used is the Robotics Expansion Pack in Simulink via MATLAB. The results were positive and served as excellent support of our assumption. By controlling the shape of the gaussian-like function, the vehicle would possess the behavior pattern of aggressive invasion or retraction in fear. The result sets a foundation for further research in bio-inspired robotics, it also provides a new attempt in controlling the Braitenberg vehicles.
Research on numerical control machine fault diagnosis based on distribution adaptive one-dimensional convolutional neural network
Authors: Yuying Zhang , Yi Lu , Jing Zhao
Published: June 2021

Numerical control machine is a high-precision and high-automation equipment, if the problem occurred in operation, it can affect the processing conditions of the machinery parts first. If the fault is aggravated, it can eventually cause the numerical control machine to stop. Spindle bearings and tools are the most vulnerable parts of numerical control machine. Previously, resonance demodulation technique was used for bearing fault diagnosis. Empirical analysis or neural network was used for tool fault diagnosis. However, the numerical control machine is an entirety, the fault is usually caused by multi-dimensional factors, the above method doesn’t work when two types of faults occur at the same time. To diagnose faults of numerical control machine, a fault diagnosis model named distribution adaptive deep convolutional neural networks (DADCNN) was proposed. This model was based on One-dimensional convolution algorithm. The Batch Normalization algorithm was involved to overcome the problem of changing data distribution in the middle layer. The t-SNE algorithm was used to visualize and view the feature classification results. Experiments show that the accuracy of this model can reach 90.29%, and it has good fault diagnosis capabilities.
Research on the Microstructure and Mechanical Properties of WC-TiC-Co/steel Joints
Authors: Zhang Feifei , Zhang Henglei , Yang Zhongyuan , Du Fengzhen
Published: June 2021

Wear-resistant layer of cemented carbide on steel can improve its wear properties in particular areas, such as oil drilling. Herein, the WC-TiC-Co/steel joint, the WC-TiC-Co wear-resistant layer covers the steel surface, is fabricated by infiltration brazed, using Cu-Zn filler alloy and WC particles as solder. The microstructure and mechanical properties of as-obtained joint are investigated. The Longitudinal interface has good bonding and the existence of transverse gaps are surveyed on interface between WC-TiC-Co and solder. The element Mapping test shows the distribution of Co element in WC-TiC-Co block is uneven. And the present of element interdiffusion forms the diffusion layer in the joining zone between base materials and solder. The hardness and phase tests indicate that Co3Fe7, W2C phase were produced during brazing, but there are few impacted on the hardness by Co3Fe7, W2C phase.
The Mechanical Property and Strengthening Mechanism of the Mg-0.5Zn-0.2Mn-0.2Sm-0.3La alloy
Authors: Fu L , Guo C R , Lu L , Jia Z , Le Q C
Published: June 2021

Tensile properties at TR with different stretch velocity, and tensile properties at T150°C were investigated in this study, and the strengthening mechanism was discussed preliminarily. Firstly, tensile properties of the Mg-0.5Zn-0.2Mn-0.2Sm-0.3La alloy at TR with the stretch velocity increases from 1 to 6 mm·min−1, and results suggest that the studied alloy exhibits low strength sensitivity as both of Rm and Rp0.2 maintaining at 240 MPa and 190 MPa, which is attributed to the not enough time for the dynamic recrystallization at the higher deformation velocity. Meanwhile, as the stretch velocity increases, although A increases first and then decreases because of the more stress concentration near grain boundaries, A maintains above 20%, suggesting the good plastic sensitivity. Secondly, when stretched at T150°C both of Rm and Rp0.2 of the Mg-0.5Zn-0.2Mn-0.2Sm-0.3La alloy decrease compared to that at TR, which is attributed to the increased dislocation movement at the higher temperature, while A increases at T150°C than at TR because of the decreased critical shear stress at the higher temperature. Even though, because the Mg12La phases impede the dislocation movement and the Sm atoms result in the solution strengthening, the mechanical properties of the Mg-0.5Zn-0.2Mn-0.2Sm-0.3La alloy are still higher than that of the Mg-0.5Zn-0.2Mn alloy at the higher temperature.
Analysis of mechanical properties and performances of laser melting forming of H13 mold steel in selected areas
Authors: jing Xiaowei , Chu zhong
Published: June 2021

When preparing H13 molds by laser melting in selected areas, due to the complex force direction of the mold during use, it is necessary to analyze the mechanical properties of the specimens at different forming angles. By preparing specimens with different forming angles (0°, 30°, 45°, 60°, 90°), tensile specimens of different forming angle specimens were made and the results were analyzed. The results show that there are many defects between layers, resulting in anisotropy of the mechanical properties of the sample. The 0° sample has the highest mechanical performance, with a tensile strength of 1933.1 MPa and an elongation of 11.1%. As the forming angle increases, the resistance Tensile strength and elongation showed a downward trend. The 90° sample had the lowest tensile strength, with a tensile strength of 1552.8 MPa and an elongation of 6.42%.
Structural parameter effect of a railway hydraulic damper on its dynamic damping characteristics
Authors: Wang Wenlin , Li Rongyong , Zhu Shan , Wu Yongming
Published: June 2021

A parametric dynamic damping characteristics model, which includes the dynamic force equilibrium equation, the flow continuity equation, the flow losses model, the comprehensive stiffness model and the valve dynamics, is established and validated by experiments. Numerical simulation of structural parameter effect on dynamic damping characteristics of the hydraulic damper is performed. The analyses show that increase of inner tube height would cause drop of dynamic stiffness of the damper, however, increase of piston diameter would lead to obvious increase of dynamic stiffness and dynamic damping coefficient, therefore, the biggest piston diameter under constraint is usually used in engineering; in addition, fluid leakage would apparently decrease damping capability of the damper, increase of leakage coefficient would lead to significant drop of dynamic stiffness and dynamic damping coefficient, and also remarkable damping force lag. The obtained full parametric model and analysis result in this work would be instructive and meaningful in further railway vehicle dynamics research and design procedures.
Application of Photocatalytic Nanomaterials in Photoelectrochemical Biosensors
Authors: Hu Yiliu , Xu Zhuoyuan
Published: June 2021

Recently, photoelectrochemical (PEC) biosensors are becoming the rising star in biosensing analysis because of their high potential to construct different biosensors with high sensitivity, selectivity, and low cost. It is well-known that semiconductor materials with intrinsic large band gaps limit their applications in the range of ultraviolet (UV) irradiation. Moreover, UV light is somewhat too energetic and has a destructive effect on biomolecules. By introducing metal nanoparticles, carbon-based nanomaterials, and even organic molecules into semiconductor materials, the light response window for these functionalized nanocomposites can be extended to the visible light region. In this review, we mainly discuss PEC biosensors’ applications based on different state-of-the-art nanocomposites in three aspects, including the environmental field, food safety field, and medical field. The design principle and performance of PEC biosensors are systematically analysed. And we also briefly look forward to the development trend of this kind of PEC biosensors in the future.
Quantum Codes Constructed by Quantum Caps in PG (4, 5)
Authors: Guan Chaofeng , Li Ruihu , Li Husheng , Zhan Xuizhen , Yao Yu , Lu Shiwei , Chen Xuan
Published: June 2021

In this paper, 57 quantum caps in PG (4,5) are found using a computer-supported search method, and related quantum error-correcting codes are constructed via CSS construction. By comparison, most of these codes have good parameters, and some of them enhance the existing results.
Structural strength of iso-polyhedral beryllium alloy rotating mirror for ultra-high-speed camera
Authors: Li Chunbo , Wen Yinchen , Chen Shoujun , Du Chenlin , Ruan Shuangchen , Yang Can
Published: June 2021

This study aims to examine the influence law of polyhedron structure on the spatial mechanical properties of ultra-high-speed rotating mirrors. To this end, polyhedral beryllium alloy rotating mirrors are investigated on the basis of elastoplastic theory and finite element method. The maximum stress is located at the end position of the contact between the shaft and the mirror body. Stress increases with the number of mirror faces. The different structures have a negative stress gradient. The structural strength of rotating mirror is affected by the strength of the mirror body material in high-speed rotation of the tensile force of centrifugal force. The lateral deformation of the mirror surface is caused by the combined effect of compression of centrifugal force generated by the material of sharp-corner and the tretching of tensile force caused by the material at the centre of the mirror at high-speed rotation. The amount of mirror surface deformation is not proportional to the number of faces. The rotating mirror with iso-quadrangular structure has the best lateral deformation effect. This research provides a theoretical basis for the research and design of rotating mirrors with high potential value.
Research on Improved Static Compensation Flux Error MARS Observer Based on SMC
Authors: Xing Pengkun , Deng Xin , Zhou Shengtao , Zhu Wenbai
Published: June 2021

Aiming at the integral drift and saturation problems of the traditional voltage model flux observer, an improved rotor flux observation scheme is proposed. A programmable low-pass filter is used to replace the pure integrator, and the flux error before the filter is corrected. The sliding mode speed controller is used to replace the traditional PI speed controller. The proposed observer can reduce the speed response overshoot of the system at medium and high speed range, reduce the steady-state time, and improve the load capacity and robustness of the system. The simulation results show the effectiveness of the algorithm.
Design and research of photovoltaic modules in energy routers based on cascaded H-bridge
Authors: Pan Mingjie , Li Xiang , Xie Da , Zhao Chenghan
Published: June 2021

Aiming at the shortcomings of traditional photovoltaic modules in energy routers, a new structure of cascaded H-bridge photovoltaic module is designed in this paper, including photovoltaic cell module, Boost/Buck module with inertial energy links, and chain H-bridge module. The maximum power point tracking (MPPT) control algorithm and the chain cascaded H-bridge control algorithm are studied, and the control angle table of the full chain 12H-bridge and the missing chain 11H-bridge is given. A 12H-bridge cascade model is built in the EMTP simulation software to verify the feasibility of the H bridge cascade output and it proves that its harmonic content is small and the power quality is high. Finally, a chain cascaded photovoltaic panel is produced, showing that it can output AC power smoothly. Comparing the daily power generation of the new photovoltaic module and the traditional photovoltaic module, it proves that it has more power generation and better irradiance tracking performance.
Research on the Linkage Between the US and China Stock Markets in the Context of COVID-19 Based on the EMD Model
Authors: Wen Yunfa , Liu Xinghua
Published: June 2021

Using the COVID-19 and the Sino-US trade war as the background, the data of the stock markets in China and the US from March 1, 2017 to September 11, 2020 are divided into 3 phases, and the high-frequency return series are extracted by empirical mode decomposition algorithm, excluding the interference of the medium-frequency data and low-frequency data. The DCC-GARCH model is used to analyze the China-US stock market linkage in the 3 phases, and the results show that: both the China-US trade war and the COVID-19 have a significant impact on the China-US stock market linkage. The Sino US trade war makes the linkage of Sino US stock market decline in the short term, while The COVID-19 made the relationship between China and the United States present an inverted “U” shape of first rising and then falling.
Research on the Structure and Performance of Bimetal Composite Hammer
Authors: Zhang Mingyi , Gao Ping , Jia Xiaobin , Tian YingChun
Published: June 2021

In order to improve the service life of the hammer head of the crusher, the high chromium cast iron-medium carbon low alloy steel double liquid composite hammer head is used to replace the single material high manganese steel hammer head; the production process uses lost foam casting instead of sand casting. This article mainly studies the production technology of composite hammers from the aspects of hammer material selection, model making, pouring system design, pouring process and heat treatment process, and uses a metallurgical microscope to observe the bonding interface, and uses a scanning electron microscope to observe both sides of the interface. For element diffusion, the universal testing machine tests the interface combination. The results show that the composite hammer has a firm bonding surface and good bonding quality.
A Brief Introduction of Carbon Nanotubes: History, Synthesis, and Properties
Authors: Chen Junqi , Wei Shiqin , Xie Haoyan
Published: June 2021

Carbon nanotube (CNT) is one of the most widely used nanomaterials recently. Since it was discovered by Iijima in 1991, its various synthesis methods were being mature in the past 30 years. The research of carbon nanotube applications in different fields has never stopped. Since a number of researchers have tested the excellent properties of CNTs, it provides an optimistic expectation about CNT applications in the future. This review summarizes the historical development of CNTs, and briefly introduces three main CNT synthesis methods and their properties.
Study surface modified nanocellulose whiskers in coconut shell
Authors: Luo Haixi , Dou Wentao , Li Guijiuan
Published: June 2021

The nanocellulose whiskers degraded by coconut shell were modified by silane coupling agent (KH-570). The structure, morphology and dispersibility of modified nanocellulose whiskers were characterized and analyzed by infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscope (TEM) and sedimentation. The results showed that the modified nanocellulose whiskers have been changed from hydrophilic to hydrophobic, and could be dispersed uniformly in ethanol without agglomeration because silane coupling agent reacts with hydroxyl groups on the surface of nanocellulose whiskers. The study showed that the crystallinity of nanocellulose whiskers were decreased with the increase of the content of coupling agent. Experiment also indicated that both of dispersibility and crystallinity could reached optimism when the amount of coupling agent is 2%. Finally, the mechanism of chemical reaction of coupling agent modified nanocellulose whisker in coconut huskwas estabilished by comparison of molecular structure of KH-570, modification process and the infrared spectrum of nanocellulose whiskers.
Preparation and characterization of a novel galactomannan based bioink for 3D bioprinting
Authors: Wu Huaying , He Ning , Huang Yuting , Zhou Zheng , Han Xiaoxiao , Liu Hairong
Published: June 2021

The limited types of bioink significantly inhibit 3D bioprinting applied to tissue engineering. In this study, galactomannan (GM) was modified by a two steps modification method, by which GM was oxidized and then methacrylated. FTIR results showed that the two steps modification of GM is successful, and the prepared compound was named as OxGM-MA that was used to test whether it can be applied as a 3D bioprinting bioink. Compared with GM, the solubility of OxGM-MA increased and 4% (w/v) OxGM-MA solution was applied to further tests. This GM based bioink, the 4% (w/v) OxGM-MA solution, displayed a low viscosity, which is 8.5 mPa • and is able to solidified by blue light irradiation. Additionally, its light solidified hydrogel displayed a pore network structure with the compressive strength of 52.3±6.7 kPa, which is strong enough for tissue engineering operations. By carrying chondrocytes, the GM based bioink was printed into a hydrogel with designed shape, which was created with CAD software previously. Following bioprinting, chondrocytes within the printed hydrogel exhibited good viability during 3 days incubation with cell culture medium, indicating the good printability and biocompatibility of the novel GM based bioink. It suggested that the novel GM based bioink can be potentially applied to cartilage tissue engineering in the future.
Dendrimer Applications for Cancer Therapies
Authors: Yan Xintao , Yang Yefei , Sun Yuchen
Published: June 2021

Human cancer therapy is a major issue in modern medical science. Lots of emerging materials are developing rapidly. Dendrimers, as a nanocarrier, are now widely used in the field of biomedicine, pharmacy, and so on. As a super-branched macromolecule, dendrimers have a series of outstanding properties. Such as simple to functionalize, have nano & symmetric dimension and cavities for host-guest entrapment. It has made much progress in drug and gene delivery. Dendrimers have higher efficiency by perfecting the surface modification methods. The small molecules, DNAs, therapeutic agents, and more can be loaded into dendrimers. Also, the cytotoxicity is reducing gradually. This review aims to make a summary of dendrimers’ history and provide guidance for future research. This review gives a brief review of dendrimers’ properties, presents how dendrimers developed in drug and gene delivery, what drawbacks are remaining to resolve.
Enhanced phase stability of a BCC structure system high-entropy alloys by decreasing elastic distortion energy
Authors: Chen Songshen , Wang Liang , Wang Lu , Xue Yunfei , Wang Benpeng
Published: June 2021

Lightweight BCC high-entropy alloys exhibit outstanding specific strength. However, these alloys usually have poor phase stability, causing brittle precipitates. These precipitates would worsen the plasticity. In order to improve the alloy performance, it is important to improve its phase stability. In this paper, the phase stability of two kinds of BCC high-entropy alloys at 400°C, 500°C and 600°C is investigated. The contributions of mixing enthalpy and elastic distortion energy to their phase stability are discussed. Besides mixing enthalpy, elastic distortion energy also plays a significant role in phase stability. Our results prove that decreasing elastic distortion energy is an effective way to improve phase stability of typical BCC HEAs.
The Influential Factors of Baking Time in Internal Friction and Bake-Hardening Properties on Low Carbon Steel
Authors: Xiaolong Jin , Feiru Zeng , Rongsheng Sun , Rendong Liu
Published: June 2021

This paper aims at exploring the distinctive ways of baking time affecting the hardening degree of the cold-rolled steel. Therefore, with different time span, the annealed sample was baked to test its baking hardening properties. The sample was analyzed micro-structurally after being annealed, pre-deformed and baked. The internal friction was simultaneously measured in terms of different processing conditions during experiments. The following findings are the significant conclusion of the experiments: The important experiment result indicated that when the degree of pre-deformation setting at 5% and the baking temperature at 170°C, the BH value increased but remained unchanged afterwards. Furthermore, when the baking time span was set at 1000 minutes, the BH value reached the maximum but would remain unchanged afterwards. When the degree of pre-deformation was set at 5%, and the baking temperature was set at 17°C with baking time 20 minutes, the SKK peak reached the maximum. When the baking time was 1000 minutes and constantly extended, the height of SKK peak rarely changed. The above experiments are designed to better illustrate and understand the significance of the hardening steel properties for future application in the automobile industry.
Research on hybrid bounding box interference check algorithm for robot offline simulation system
Authors: Li Jing , Zhong Zhen , Fan ChangQi , Shen NanYan , Lu YiHao , Feng ZeYuan , Dai ZhenLiang , Yu Hong
Published: June 2021

Aiming at the problem that the traditional industrial robot may interfere with the workpiece when running in the offline simulation environment, a hybrid bounding box algorithm based on octree is proposed. First, AABB is used for rough interference checks, which quickly eliminates the pairs of impossible objects to intersect, then OBB hierarchical bounding box is used for precise interference checks. A new OBB construction method is proposed, which recalculates the semi-axis length and centre of the constructed traditional OBB to make it surround the object as much as possible and reduce the space gap. A traversal method based on distance priority is proposed, which traversed the closest node every time by maintaining a priority queue. And in the update strategy, “update on demand” is adopted, which discards updating the entire tree before each intersection and only updates the current node during the intersection traversal to achieve the purpose of partial update. Experiments show that the proposed hybrid bounding box algorithm can detect interference faster and perform better real-time performance and accuracy.
Synthesis and applications of silver nanocomposites: A review
Authors: Wu Chunyang , Xu Shengtao , Wang Wenmin
Published: June 2021

Nanomaterials refer to materials whose structural unit size is between 1 nanometer and 100 nanometers. Since nanoparticles’ size is close to the coherence length of electrons, their properties have also changed greatly due to the self-organization brought about by strong coherence. Therefore, noble metal nanoparticles have unique physical, chemical, and biological properties. This paper mainly studies the silver nanoparticle material, one of the precious metal nanoparticles. The silver nanoparticle is modified to graphene, metal materials, fiber materials, ceramic materials, and polymers to form a silver-based composite material, which improves its antibacterial, electrical conductivity, and Chemical durability, photocatalysis, and other capabilities. They can be applied to medical, environmental, industrial, biological, food and other fields, providing a reference for in-depth research on the properties of nano-silver particles and the continuous development of their application prospects.
Simulation and Practice of Guided Wave Test Method in Circular Rod
Authors: Peng Ding , Guangfei MA , Shudong Gong , Pengxiang YU , Bo Chen , Xiao Yang , Yanshan Song
Published: June 2021

Guided wave mode and dispersion curve in the circular rod are analyzed, and the time domain waveform of Φ20mm*2m circular rod is analyzed. Though finite element simulation and experiment, the variation law of reflection coefficient of different guided wave modes is analyzed. The L(0,1) is consistent with the change trend of F(1,1) modes for axial and circumferential defects, and the simulation results of L(0,1) modes are consistent with the test results.
Ground-mounted vs floating photovoltaic (PV) power plant: a trade-off using game theory in utility-scale PV power plant investment decision making
Authors: Nico Siagian Herry , Saputra Febriyadi
Published: June 2021

The development of a renewable energy power plant in Indonesia will increase rapidly in the future in line with the long-term electricity policy to achieve the renewable energy target of 23% by 2025. One type of renewable energy power plant that will be highly developed is the Photovoltaic (PV) power plant, both built on the ground or floating type. Floating PV power plants do not require large amounts of land. However, the construction of a floating PV requires a floater system along with mooring and anchoring, which costs up to 20-30% of the project cost. This paper aims to optimize and simulate the critical factors so that investors and utility companies can make a decision whether to build a PV power plant on land or floating in a used mine area. Critical factors that affected the PV power plant development are analyzed using Critical Success Factor Analysis. Furthermore, the analysis is carried out using Game Theory to obtain optimal decisions. Based on the analysis, if the other critical factors are assumed to be the same, the construction of a floating PV Power Plant in a typically used mining area will provide optimal commercial value at a depth of reservoir of fewer than 60 meters. If the depth of the reservoir is more than 60 meters, the ground mounted PV will provide a more optimal commercial value.
The effect of ultrasound duty cycle in biodiesel production from Ceiba pentandra
Authors: Iderisa Fazril , Susan Silitonga Arridina , Kusumo Fitranto , Halim Shamsuddina Abd , Nomanbhaya Saifuddin M. , Sebayang A. H. , Sutrisno J. , Bela N.
Published: June 2021

This study investigated the effect of the duty cycle for the transesterification of Ceiba pentandra oil. The important parameters of a duty cycle (pulse-mode operation) and energy usage in the transesterification reaction process were presented and showed that a maximum biodiesel yield of 99.24 % was achieved for 75% duty cycle with a pulse combination of 6 sec ON and 2 sec OFF. That was under the optimum conditions of 60% methanol to oil ratio, 1.00 wt% of KOH, reacted for 50 minutes. The obtained biodiesel was then analyzed using FTIR spectroscopy, and physiochemical properties of the Ceiba pentandra biodiesel then determined. It found that all the properties comply with the fuel specifications set by both ASTM D6751 and EN 14214 standards.
A facility location problem for palm-oil-based biodiesel plant: case study in North Sumatera Province
Authors: Silalahi Fitriani Tupa R. , Simatupang Togar M. , Siallagan Manahan P.
Published: June 2021

As a country that supports the development of renewable energy, Indonesia has policies to direct the use of biodiesel as fuel energy source. In 2020, the Government of Indonesia (GoI) implements mandate of biodiesel from palm oil, one of Indonesia’s best plantation products. The increase in the mandate up to B30 makes the national biodiesel plant’s capacity to operate up to 80% so that a new plant is needed to meet biodiesel for national and export demand. Taking North Sumatra province as the location of study, this research expects to determine the biodiesel plant’s location that will be built to meet the needs of petrodiesel fuel in the North Sumatra area to minimize transportation costs at each stage. Mathematical modelling is conducted to reach the objective. The model aims to determine the most appropriate location and size of the biodiesel plant to be made, by taking into account the distance between several two-transportation points, the availability of feedstocks, demand, and supply chain costs. Mixed-integer linear programming (MILP) is employed to simulate the model. Result suggests that two regions are suitable locations for establishing biodiesel factories to meet the needs of the people of North Sumatra, namely Langkat Regency and Serdang Bedagai Regency. The result can serve as recommendations for policymakers to minimize the biodiesel supply chain cost in North Sumatra.
The implementation of energy diplomacy by sub-state actors: approaches of Surabaya toward Kitakyushu
Authors: Rudiany N P , Anggraeni S D , Firmansyah M , Nurhidayah G M
Published: June 2021

In many countries, energy diplomacy is usually carried out by the national government as the primary unit, through bilateral or multilateral agreements. However, it seems that Surabaya and Kitakyushu’s cities have carried out intensive cooperation in the energy sector since the 2010s. This condition shows that the implementation of energy diplomacy has also been conducted at the substate level. Even though it focuses on the active role of the two cities, the meaning of energy diplomacy has not disappeared, but instead, it has expanded. This paper analyzes the City of Surabaya, Indonesia, approaches toward the City of Kitakyushu, Japan, in developing the energy sector, especially to strive for an energy-efficient city planning system in Surabaya. This paper’s analytical framework is based on energy diplomacy and diplomacy by sub-national actors in international relations. The finding of this study is that the diplomacy carried out by the City of Surabaya toward Kitakyushu is classified as a practice of energy diplomacy. The diplomacy is carried out through a sister city approach.
Bioenergy Sustainable development in Indonesia and its relation with SDGs goal
Authors: Harahap Fumi
Published: June 2021

The global Sustainable Development Goals (SDGs) are now converging to address the economic, social and environmental dimensions. Bioenergy can play a significant role in achieving the agreed SDGs on climate change, thereby advancing climate goals, food security, better land use, and sustainable energy for all. Bioenergy is essential in the past, present and future energy systems. At least 10% of global energy supply comes from bioenergy source, of which two-thirds is used in developing countries for cooking and heating. Compared to other renewable energy sources, bioenergy is the most problematic area due the multitude of biomass feedstock, technology pathways, and end products which encompass the biomass to energy conversion. The use of biomass for bioenergy is expected to increase driven by several SDGs (goals: 2, 7, 8, 9, 11, 12, 13, 15), but bioenergy also act as sustainability safeguards. By exploring bioenergy in a context of multi-sectoral objectives and synergies, pathways can be found to promote the transition to sustainable modern bioenergy. This paper explores pathways to enhance resource efficiency, particularly for bioenergy production in the palm oil industry in Indonesia for meeting the SDGs.
Life cycle assessment of natural gas and crude oil: case study in PT Pertamina Hulu Mahakam – BSP Site
Authors: Muhyinsyah A , Witono JA , Santosa E
Published: June 2021

Life cycle assessment (LCA) is a methodology for assessing the environmental impacts of a product. PT Pertamina Hulu Mahakam - BSP Site has conducted an LCA study to quantify the environmental impact of natural gas and crude oil producing and then identify the activities that give significant impact on the environment which is referred to as a hotspot. The methodology used in this LCA study refers to ISO 14040:2016 and 14044:2017. The impact categories considered are Global Warming Potential (GWP), Acidification Potential (AP), Eutrophication Potential (EP), Ozone Depletion Potential (ODP), Photochemical Oxidant Creation Potential (POCP), Abiotic Depletion Potential (AD), Abiotic Depletion Potential -fossil (ADP-fossil), Human Toxicity Potential (HTP), Eco-Toxicity Potential (ETP), Land Used (LU) and Water Footprint (WFP). The result of this study identifies several activities in PT Pertamina Hulu Mahakam – BSP Site that can be categorized as hot spot: (1) The oil and gas extraction process, (2) Emission from transportation activities (3) Emission from electricity generator unit and compressor unit (4) Gas venting from surface facilities (5) Steel production that used in offshore platform infrastructure and (6) Fugitive emission from produced water. Several recommendations have been proposed to reduce the impact of those activities: reduce water content in the oil and gas extraction process, optimized transportation routes, use more environmentally friendly fuel for transportation activities, optimize the performance of compressor and electricity generator, and install the new offshore platform with a slimmer design. This study shows that LCA can help oil and gas producers to improve operational efficiency and reduce the impact on the environment to achieve sustainable development.
Analysis of printed circuit heat exchanger (PCHE) for Small modular molten salt reactor (MSR)
Authors: Suroto B J , Indarta K A , Nurmawati A
Published: June 2021

Energy is the backbone of defense and essential for the effectiveness of operations. The archipelago country like Indonesia has a specific characteristic when deploy the army separated over the country will have deep complexity in energy distribution and security. The mobile nuclear power plant is interesting to evaluate, and we interested in heat transfer process in the heat exchanger. The paper presents the potential of the application of a printed circuit heat exchanger (PCHE) on small modular molten salt reactors (MSR) for the military. The Heat exchanger is played a crucial role in the nuclear reactor design where the size compaction and efficiency improvement two issues that must be solved. The PCHE promise some advantages such as high effectiveness, high surface area per volume, light and compact. We evaluate and compare the performance of the heat exchanger of the MSRE ORNL 8 MWTh with PCHE’s design where MSRE a benchmarking. The result shows that low-pressure drops, low-pumping power and high effectiveness and compactness (low-dimension). We recommended that PCHE is applied on MSR than conventional HX like a Shell tube heat exchanger (STHE) of MSRE ORNL.
Sustainable resources management to support Sei Mangkei SEZ as an eco-industrial park
Authors: Husni Nobrya
Published: June 2021

Sei Mangkei SEZ as an eco-industrial park with the development of downstream of natural resources resulting from plantations in North Sumatra, especially oil palm and rubber, emphasizes the principle of sustainability and environmentally friendly in exploring natural resources into quality ready-made products. The need for energy is very necessary to support the development of the region, region’s ability to provide energy independently is still limited to using of oil palm empty fruit bunches as an alternative source of electricity in the palm oil mill. The use of by-products is one aspect of sustainability that has been done in the Sei Mangkei SEZ. However, a more comprehensive analysis is needed to meet the energy needs of the Sei Mangkei SEZ as a whole so that the area’s operations can proceed as expected. This paper is written with a qualitative approach and then analysed descriptively to obtain renewable energy management to be applied to the Sei Mangkei SEZ. The research informants were the managers of the Sei Mangkei SEZ, namely: the administrator of the Sei Mangkei SEZ, PTPN III, and PT. Kinra. This paper will present the available energy sources, energy management problems, and appropriate energy management advice. Primary data were obtained from interviews and documents, as for secondary data obtained from previous research reports, articles from relevant journals, and regulations that support the application of sustainable energy management in the Sei Mangkei SEZ. This paper concludes that SEZ Sei Mangkei has implemented the principle of the eco-industrial park and can develop as planned. An alternative to meet the needs of electrical energy in Sei Mangkei SEZ are obtained from biomass power energy, namely: shells, empty fruit bunches, palm oil mill liquid waste, and domestic solid waste. This research suggests that biomass energy as an alternative source of electrical energy needs to be applied as soon as possible before the area operates optimally, and the demand for electrical energy is increasing.
Milk production and lactation length of F2 Anglo Nubian × Etawah grade does
Authors: Praharani L , Anggraeni A , Rusdiana S
Published: June 2021

Goat milk has many benefits that resulted in increasing its consumption. A study was carried to evaluate total milk production and lactation length of F2 Anglo Nubian (AN) × Etawah Grade (PE) crossbred does in different lactation numbers. There were thirty-eight does of F2 AN × PE used in this study. All does were raised in IRIAP laboratory pens and the same feeding system and management. Daily single hand milking data were collected for total milk production per lactation of the first-third lactation between the year 2018–2019. The data were analyzed using a linear model from the SAS program including lactation numbers as a source of variation. Results had shown that lactation numbers significantly affected total milk production and lactation length (P<0.05). The first lactation of AN × PE does perform the lowest milk production and lactation length while the thirds showed the highest. The milk production and lactation length increased as lactation numbers increasing. It can be concluded that total milk production and lactation length were affected by lactation numbers. This study might be used as a consideration in improving milk production of crossbred goats using AN goats.