bluuebunny/crossref_metadata_2025 huggingface dataset:
Data detection technology of wireless sensor network based on non-stationary filtering
Authors: Lu Xinghua , Huang Jiahao , Luo Guohua
Published: December 2021

By optimizing the data detection performance of distributed wireless sensor networks, the data sensing and collecting ability of wireless sensor networks can be improved. Traditional methods adopt statistical characteristic parameter detection algorithm for distributed wireless sensor network data detection. Distributed wireless sensor network data has strong time-frequency coupling, so it is difficult to realize frequency domain spatial parameter clustering in frequency domain, and the detection performance is not good. A distributed wireless sensor network data detection algorithm based on non-stationary filtering and high-order statistical feature peak retrieval is proposed. The data model of distributed wireless sensor network is constructed under the interference of color noise. The weak vibration signal is subjected to time-frequency analysis and noise separation by non-stationary filtering, and the spectral peak of distributed wireless sensor network data is searched by the fourth-order cumulant slice post-operator to realize the optimal detection of signals. The simulation results show that the algorithm has a high probability of accurate detection, and has a good ability of suppressing noise and noise sidelobe information interference, which improves the probability of accurate detection of distributed wireless sensor network data under low signal-to-noise ratio.
A High Speed Redundant IO Bus for Energy Power Controller System
Authors: Lou Qinghui , Sun Liguo , Lu Haisong , Xu Weifeng , Wang Zhebei , Cai Dan , Shi Xiangjian
Published: December 2021

This paper designs and implements a High Speed Redundant IO Bus for Energy Power Controller System. The physical layer adopts multi-point low-voltage differential signal standard. This bus has the characteristics of high real-time, high throughput and easy expansion. The controller communicates with IO module by A/B bus alternately, monitors link status in real time and collects IO module data. Non real time slots can be used to control non real time messages for IO modules such as time synchronizing and memory monitoring. The controller ARM core runs QNX real-time operating system, and transmits the message needed to communicate with IO modules to the FPGA through DMA. After receiving the message, the FPGA parses the message and automatically fills in the CRC check code and frame end flag at the end of the message. When the FPGA receives the data feedback from the IO module, it performs CRC verification. If the verification passes, it fills the corresponding module receiving buffer. Otherwise, it fills the CRC verification error flag in the register of the corresponding IO module to reduce the load of the arm core.
Application in photovoltaic MPPT based on improved hysteresis loop comparison method
Authors: Shang Liqun , Li Fan
Published: December 2021

In order to overcome the misjudgement and oscillation of the traditional perturbation observation method when tracking the maximum power point of the PV system, this paper proposes a fixed-zone variable-step hysteresis comparison algorithm. The bi-directional perturbation of the hysteresis loop can effectively avoid the occurrence of misjudgement; after setting the partition voltage threshold, different step lengths can be used to track specific regions, which can ensure the tracking speed and maintain the system stability. Finally, the proposed algorithm is validated in Matlab/simulink and the results show that the method is effective in tracking the maximum power point of the PV system in all aspects compared to conventional algorithms.
The application of Deep Reinforcement Learning in Coordinated Control of Nuclear Reactors
Authors: Li Jing , Liu Yanyang , Qing Xianguo , Xiao Kai , Zhang Ying , Yang Pengcheng , Yang Yue (Marco)
Published: December 2021

The nuclear reactor control system plays a crucial role in the operation of nuclear power plants. The coordinated control of power control and steam generator level control has become one of the most important control problems in these systems. In this paper, we propose a mathematical model of the coordinated control system, and then transform it into a reinforcement learning model and develop a deep reinforcement learning control algorithm so-called DDPG algorithm to solve the problem. Through simulation experiments, our proposed algorithm has shown an extremely remarkable control performance.
A spatial-temporal correlation based method for advanced persistent threat detection
Authors: Wang Luoli
Published: December 2021

Advanced Persistent Threats (APT) have caused severe damage to the core information infrastructure of many governments and organizations. APT attacks usually remain low and slow which makes them difficult to be detected. In this case, the way of correlatively analyzing massive logs generated by various security devices for effectively detecting the new type of cyber threat turns out to be more and more significant. In this paper, on the basis of analyzing the principles and characteristics of APT, we propose an intelligent threat detection method based on the expanded Cyber Attack Chain (CAC) model and the long short-term memory network (LSTM) autoencoder to extensively correlate malicious behaviors from spatial and temporal dimensions, which provides a brain new idea for the application and practice of complex network attack detection.
An Absolute-value Detector with Threshold Comparing for Spike Detection in Brain-machine Interface
Authors: Yuan Mingzheng
Published: December 2021

This research designs an absolute-value detector with the function of threshold comparing. Specifically, it is an essential device in the spike detection of the brain-machine interface. The optimized design in the research can accomplish the main functions in spike detection and has good performance in both delay and energy consumption. It comes up with two types of design at the beginning. To make the design reliable and comprehensive, it decides to discuss both methods in this paper. The first design is using a full adder, multiplexer and comparator. The concept of its logic circuit is adding the logic one to the input when the given input data is negative, keeping the original information as the given input data is positive. To achieve the function of adding, this study chooses the full adders. The primary purpose of using multiplexers is to select from the processed input and original input, and the choice depends on the most significant bit (MSB) of the input data. To compare the absolute value of the input data with a given threshold, this research used a multi-bit comparator. The second design is based on the fundamental algorithms of calculating total numbers. It indicates that this study can operate it with the threshold value through a subtractor when the input is negative. On the contrary, an adder can be used when the information is positive. Based on the concept of logic optimization, this study chooses to use the only subtractors, and it just needs to focus on the borrow bit, which can indicate the more significant number. By connecting the MSB of the input with the subtractors through XOR gates, the selection can be achieved without using any multiplexer. In the process of removing and replacing the devices, it reached the optimization of the design. Then, this paper compared the minimum delay by calculating each stage’s size and finding that the second design is better. Finally, based on the dual design, this essay computed the energy consumption in the circuit and implement VDD
optimization to obtain the minimum energy.
Improved Design of a 4-bit Absolute-Value Detector Using Simplified Chain Carry Adder
Authors: Dong Xinhang , Jing Boyuan , Yang Xiang
Published: December 2021

4-bit absolute-value detector (AVD), as one of the basic implementations of bit arithmetic with logic circuits, can help grab a better understanding about digital integrated circuits. Conventional 4-bit AVDs scheme in a multi-comparator and multiplexers, or need to consider multiple situations of overflow and carry-in, both of which could make the final circuit to be complex, labyrinthine and inefficient in the meantime. In this paper, a new design of 4-bit AVD is proposed, the topology of which includes a 2’s complement calculator and a specially designed logic circuit known as chain carry adder (CCA). The whole circuit is concise and the critical path is rigorously considered to make it as short as possible. The delay is set to 1.5 times its minimum, which is positively corresponding to the length of the critical path, the energy accordingly reaches its lower limit. Gate sizing and Device Voltage (VDD) optimization are proceeded for the exact purpose of proving that the circuit energy is minimized.
A New Type of Sliding Mode Observer for Permanent Magnet Synchronous Motor Control
Authors: Cheng Sheng , Xu Yu-Fa
Published: December 2021

Aiming at the high-frequency oscillation and estimation accuracy problems of traditional sliding mode observers in the control process of permanent magnet synchronous motors, a sensorless control method for permanent magnet synchronous motors based on a new approaching law sliding mode observer is proposed. Based on the construction of a permanent magnet synchronous motor two-phase static coordinate system model, a sliding mode observer is used to estimate the back electromotive force, and then the rotor speed and position information are obtained. Finally, a simulation experiment is carried out. The results show that the new sliding mode observer based on the new approaching law effectively reduces the high frequency chattering of the system, improves the estimation accuracy of the system, and has better control performance.
Dynamic equivalence of doubly-fed wind turbines based on parameter identification and optimization
Authors: Li Yaxin , Yang Jie , Yi Bainian , Fang Rengcun , Zhang Dongyin
Published: December 2021

The dynamic equivalence and modeling of large-scale wind farms is the basis for studying the problem of multi-temporal and spatial scale wind farms grid connection, and the establishment of a high-precision equivalence model is a key issue among them. This paper takes doubly-fed wind turbines as the research object. Aiming at the problem of large dynamic errors in direct aggregation of equivalents into a single unit, an equivalent model combined with particle swarm optimization algorithm is established to improve the accuracy of dynamic equivalents. The electrical parameters, reactive power reference values, active power controller parameters, and active DC voltage controller parameters are optimized using particle swarm optimization. The research results show that the equivalent model after optimizing the parameters of the active power and DC bus voltage controller is the closest to the detailed model in describing the dynamic characteristics of multiple machines.
Linear Active Disturbance Rejection Control based on Finite Impulse Response filter for harmonic control in microgrid
Authors: Yang Xiong , Zhang Xuhui , Guo Jiahao
Published: December 2021

Island for micro grid is vulnerable at the run time, which is caused by the problem of load fluctuation, voltage frequency deviation, and distributed power supply power. These issues are generated by the uncertainty of three-phase voltage waveform output at the same time. All of these problems are urgently needed to solve, this paper designs a linear active disturbance rejection control to do robust estimation. This controller is based on optimal finite impulse response (FIR) filter, which is also combined with the immunity of the micro grid system harmonic method. The proposed controller is simulated. And it is compared with the classical PI controller and the linear active disturbance rejection controller respectively too. The simulation results show that the performance and robustness of the proposed model are better than those of traditional algorithm in microgrids.
Intrusion Detection Method of Electric Power Information Network in Cloud Computing Environment
Authors: Zhang Jiaqi , Feng Guoping , Zhou Dexi , Li Mingjiu
Published: December 2021

With the widespread application of power grid systems, the information security problems faced by power grids have become more obvious. Various internal and external intrusion attacks that occur frequently have become an important issue affecting the normal operation of power generation and operations. The purpose of this paper is to study the intrusion detection method of electric power information(PI) network in the cloud computing environment. With the help of the cloud platform’s ability to process big data, and based on the analysis of the PI network structure, a DBN optimized BP network algorithm is proposed, and the optimized BP neural network is used as a runtime classification program. Experimental results show that MR-DBN-BP has a detection rate of 96.7% for intrusion detection of PI networks, which can effectively detect intrusions and effectively protect the power dispatch system network.
Design of entertainment drone with rotating LED display technology
Authors: You Anhua , Li Jiahao , Xu Zifang , Liu Wencong
Published: December 2021

The drone light show is a popular form of performance. This paper designs a new type of entertainment drone with rotating LED display technology. This drone is equipped with a rotating LED display, a single drone can display a complete picture, and has a good display effect. The application of the new entertainment drone can reduce the cost and technical difficulty of the drone light show, and expand the applicable scenarios of the drone light show.
Analysis and Testing of the Dynamic Characteristics of Rotor Worktable
Authors: Wang Jianmin , Liu Dong , Bian Yi
Published: December 2021

The finite element modelling, mesh generation and modal analysis of the rotor worktable are carried out by combining the analysis technology of finite element software in this paper. Then, the software analysis results and the actual experimental results are compared and analyzed, so as to get the causes of error, which can provide good basic data for the use of the rotor table in the future that could better meet the needs of scientific research and teaching.
Simulation of two dimensional OCDMA-PON system based on FBGs
Authors: Zheng Mingzhu , Wu Qiwu , Zhou Yang , Jiang Lingzhi , Liu Jiaqi
Published: December 2021

In order to study the effect of transmission distance on the performance of optical code division multiplexing passive optical network systems based on fiber Bragg Grating (FBG), a two-dimensional OCDMA-PON system based on cascaded FBGs is designed and constructed by using the VPI optical communication software. The spectrum, waveform and eye diagram of the output signal are analyzed by setting different fiber lengths in the system. The experimental results show that different fiber lengths have different effects on the system. Within a certain transmission distance, the longer the fiber length, the smaller the error generated by the output signal and the better the signal quality; beyond this certain distance, the quality of the output signal deteriorates sharply and the error generated becomes larger.
Research on threat detection in cyber security based on machine learning
Authors: Ke Qiwei
Published: December 2021

The volume of the data has been rocketed since the new information era arrives. How to protect information privacy and detect the threat whenever the intrusion happens has become a hot topic. In this essay, we are going to look into the latest machine learning techniques (including deep learning) which are applicable in intrusion detection, malware detection, and vulnerability detection. And the comparison between the traditional methods and novel methods will be demonstrated in detail. Specially, we would examine the whole experiment process of representative examples from recent research projects to give a better insight into how the models function and cooperate. In addition, some potential problems and improvements would be illustrated at the end of each section.
Optimization of operation sequencing based on GA-Jaya algorithm
Authors: Zheng Kai , Zhang Rui , Zhu Zhen-Wei , Zhao Hua-Dong
Published: December 2021

To solve the operation sequencing problem in CAPP that is a difficult problem, combining the idea of genetic algorithm, an GA-Jaya algorithm is proposed to minimize the total cost. In the GA-Jaya, the population is initialized according to the procedure priority adjacency matrix which makes the population all meet the process priority relationship. Mutation iteration operator and two kinds of crossover iteration operator are designed for process sequence and processing resource evolution. The GA-Jaya algorithm is applied to a typical case, and compared with the existing genetic algorithm, particle swarm optimization algorithm and ant colony optimization algorithm. The results show that the average quality of the solution obtained by the GA-Jaya algorithm is better than the existing genetic algorithm, particle swarm optimization algorithm and ant colony optimization algorithm.
Application of Fuzzy Neural Network PID In Laser-guided Mortar Projectile
Authors: Song Yang , Jia Fangxiu , Wang Xiaoming , Meng Dingming , Zhuang Lei
Published: December 2021

Based on the high control performance requirement of laser-guided mortar control system, the permanent magnet synchronous motor (PMSM) is adopted in this paper as the electromechanical actuator of the system, the mathematical model of the motor is analyzed, and the vector control technology is adopted to achieve precise control of position, speed and torque of the electromechanical actuator. Aiming at the characteristics of non-linearity, strong coupling and large parameter changes of the system in flight, an improved fuzzy neural network PID control method is proposed by combining the classical PID control algorithm with fuzzy control and neural network control algorithm to realize the real-time tuning and optimization of PID parameters. The mathematical model of the electromechanical actuator control system is established and simulated. The results show that the fuzzy neural network PID control has good tracking performance, small amplitude error, and strong adaptability to load changes.
Research on recommendation algorithm of Graph attention Network based on Knowledge graph
Authors: Zeng Yiping , Liu Shumin
Published: December 2021

The introduction of knowledge graph as the auxiliary information of recommendation system provides a new research idea for personalized intelligent recommendation. However, most of the existing knowledge graph recommendation algorithms fail to effectively solve the problem of unrelated entities, leading to inaccurate prediction of potential preferences of users. To solve this problem, this paper proposes a KG-IGAT model combining knowledge graph and graph attention network, and adds an interest evolution module to graph attention network to capture user interest changes and generate top-N recommendations. Finally, experimental comparison between the proposed model and other algorithms using public data sets shows that KG-IGAT has better recommendation performance.
Numerical Analysis of the Aerodynamic Characteristics of the Open Line Intersection of Fast Freight Train with the Speed of 160 km/h
Authors: Zhang Yue , Wang Dongping
Published: December 2021

With the increase of the speed of fast freight train, the aerodynamic effect of freight train in open-line intersection is more obvious. However, at present, there are many domestic researches on the aerodynamic characteristics of high-speed train open-line intersection, and almost no researches on fast freight train. Therefore, it is of great significance to study the aerodynamic characteristics of open line intersection of fast freight train in order to improve the safe operation of freight train in China. Based on the theory of computational fluid dynamics and finite volume method, uses FLUENT software to numerically calculate the three-dimensional, unsteady, compressible and turbulent flow fields in open line intersection of fast freight train at different speeds. The calculations results indicate that: when two freight trains meet, the amplitude of the pressure wave at the intersection side is the largest and the closer to the train bottom, the greater the amplitude of the pressure wave. The pressure amplitude of the bottom measuring point is 34.09% higher than that of the top measuring point. When two cars intersect at the same speed, the higher the speed, the greater the pressure amplitude and the pressure amplitude is proportional to the square of the speed. The fitting formula is: ΔP = cV2
; When two trains intersect at different speeds, the impact on freight train with lower speed is greater than higher one.
Application of ABS Regulator Solenoid Valve Control
Authors: Pan GuangYong , Kong LinZhan , Yu JunHua , Huang MeiLong , Tong Xin
Published: December 2021

In the air brake system of the vehicle, the electromagnetic valve of the brake regulator belongs to the anti-lock brake system. In case of an emergency, the wheel is prevented from being locked and slipped during braking, and the most suitable braking force is applied to each wheel, so that the adhesion force [1] of the tire to the ground is fully utilized, which plays a vital role in improving the safety of the vehicle. In ABS anti-lock system, the regulation of solenoid valve plays an important role. This paper analyzes and applies a kind of solenoid valve control.
Structural Design and Dynamics Simulation Analysis of A Certain Type of Co-frame Launcher
Authors: Liu Hanchao , Guo Anxin , Wang Xuezhi
Published: December 2021

To study the dynamic response of a certain type of co-frame launcher during launch, this article uses the 3D modeling software Pro/E to import the model into Adams from the perspective of launch dynamics. the launch dynamics model of the shared-frame launcher is established. We apply the ejection thrust of the two types of missiles to the corresponding ejection devices and measure and collect the dynamic parameters of the cartridge system. The simulation results show that the dynamic parameters of the A and B missiles are in line with the available overload design requirements. The B-type missiles are superior to the A-type missiles in terms of ballistic orbit contact force and ejection attitude.
Simulation of Particle Motion Behavior in Fluidized Bed Opposed Jet Mill
Authors: Yang Kangwei , He Xuewen
Published: December 2021

In order to study the influence of the internal flow field of the fluidized bed opposed jet mill on the motion behavior of particles, Computational Fluid Dynamics (CFD) and Discrete Dlement Method (DEM) are used for coupling calculations. By adjusting the nozzle spacing and inlet pressure, Numerical simulation is carried out on the process of particles collisions with each other after accelerating under the high-speed jet produced by the nozzle. The trajectory of the particles in the flow field of the collision area and the change of the collision state of the particles are analyzed. Finally, the best parameters are selected based on the total collision energy. The results show that the particles will gradually shift and spread during the acceleration process. The reduction of the nozzle spacing is beneficial to increase the probability of particle collisions. However, if the spacing is too small, the particles cannot be fully accelerated; the increase in inlet pressure will increase the kinetic energy of the particles, and number of collisions is almost unaffected. By comparing the total collision energy, the best-simulated preparation conditions are selected as 110mm and 1.1MPa.
Theoretical and experimental research on a new rotating standing wave ultrasonic motor
Authors: Wang Xiaozhu , Zhang Jian
Published: December 2021

In this paper, a new rotating standing wave ultrasonic motor with multiple driving teeth is proposed. Using the method of adding additional teeth, the correction of the B06 surface of the ultrasonic motor vibrator is expected, the design of the optimum position of the drive tooth is realized. At the same time, a method of reducing the stiffness of the rotor is proposed, and the flexibility is met, the integrated design of the rotor and the pressure device can be realized by removing the disc spring. The accuracy of the finite element analysis is verified by the vibration test of the prototype oscillator. The finite element analysis of the main structure parameters of the influence oscillator mode and natural frequency is carried out. It provides theoretical basis for the design and machining of vibration.
Study on creep perform of epoxy resin for launch canister
Authors: Wei Fu-Quan , Yang Wen-chao , Zhan Zhe-xian , Yu Cun-gui
Published: December 2021

In order to study the creep perform of the launch canister, creep perform of the epoxy resin (matrix material) were studied. The creep model of epoxy resin was established based on Bailey-Norton model. Constant stress tensile creep tests at room temperature were carried out on epoxy resin specimens under different stress levels, and the model parameters were obtained by fitting the test data. The finite element model of the specimen was established in the ABAQUS software and the tensile simulation was carried out. The simulation results are consistent with the test results. Results show that time-hardening model can describe the short-term creep perform of epoxy resin with error less than 20%.
Decomposition test study on short-process mechanical strengthening equipment of alkali decomposition of tungsten ore
Authors: Zhang Jie , Lin Jingzhang , Weng Lingxiao
Published: December 2021

The traditional alkali decomposition process and equipment of tungsten ore are limited by the situation that the grade of tungsten ore resources is decreasingy and the impurity content is getting higher and higher. A set of high-efficiency alkali decomposition process equipment of tungsten ore based on mechanical strengthening is researched and developed in this paper. Fourteen groups of mechanical strengthening decomposition tests were carried out on three particle sizes of ore samples. which verifies the feasibility and reliability of strengthening the alkali decomposition of tungsten ore by the test prototype.
Simulation Study on Liquid Cooling of Lithium-ion Battery Pack with a Novel Pipeline Structure
Authors: Lv Chao , Xia Tianyuan , Yin Hongxin , Sun Minghe
Published: December 2021

Lithium-ion battery is widely used as the mainstream power source of electric vehicles owing to its high specific energy and low self-discharge rate. However, the performance of the lithium-ion battery is largely hindered by its heat dissipation issue. In this paper, lithium-ion battery pack with main channel and multi-branch channel based on liquid cooling sys-tem is studied. Further, numerical simulation was used to analyze the effects of coolant temperature and flow rate on cooling performance. Based on the original pipeline structure, a new pipeline structure was proposed in the present work. The results show that increasing the cool-ant flow rate not only reduces the maximum temperature of the battery pack, but also reduces the temperature difference. Lowering the coolant temperature could largely decrease the maximum temperature of the battery pack, but it tends to widen the temperature difference and worsen the temperature uniformity. Up-on comparison, maximum temperature is found to be decreased by 0.44K, whereas, the temperature difference of the battery decreased and the temperature uniformity is improved.
Design of DC motor controller based on MBD
Authors: Hu Xu , Lu Peng , Yang Yan , Pan Chunpeng , Wu Guoguo , Ping Yan
Published: December 2021

This paper designs a direct current (DC) motor controller based on Arduino and Simulink to solve the problems of poor openness, complicated programming and difficult signal detection of the existing teaching experimental equipment. The controller integrates the Model-Based Design (MBD) concept, involving single-chip microcomputer, system modeling, micromotor, automatic control and other technologies. The hardware system includes Arduino, encoder, driver, input/output and other interfaces. The software system uses Simulink as the software development platform of the experimental device. It has the functions of algorithm design, simulation, execution, real-time data observation, etc. The limiting incremental PID control algorithm is used to control the speed of the DC motor, and the experimental results verify the design requirements. The hardware and software systems have the characteristics of good openness, fast implementation, safe and reliable, low cost, can complete the verification and improvement of various algorithms such as motor control, and can meet the teaching and research needs of the training of new engineering and technology.
Feasibility study of a method for identification and classification of magnesium and aluminum with ME-XRT
Authors: Yeyu Y. , Wenbao J. , Daqian H. , Aiyun S. , Can C. , Mengcheng Q. , Gangqiang Z. , Limin J. , Yajun T.
Published: December 2021

The identification of magnesium and aluminum in scrap metal
recycling has always been a difficult point. In this paper, a
material identification method of multi-energy X-ray transmission
(ME-XRT) based on photon counting detector (PCD) and machine
learning algorithm was proposed and used to identify and classify
magnesium and aluminum. This method includes three main steps: using
PCD to obtain X-ray attenuation images of five energy bins, feature
extraction, and the machine learning classification. The performance
of several machine learning models was compared for the fine-grained
classification task. The prediction results demonstrate that the
best achieved recognition rates of aluminum and magnesium are
96.43% and 98.81%, respectively.
Assessment of shutdown dose rates in the ITER Collective Thomson Scattering system and in equatorial port plug 12
Authors: Chambon A. , Luís R. , Klinkby E. , Nietiadi Y. , Rechena D. , Gonçalves B. , Jessen M. , Korsholm S.B. , Larsen A.W. , Lauritzen B. , Rasmussen J. , Salewski M. , Fabbri M. , Morillo C.
Published: December 2021

The ITER Collective Thomson Scattering (CTS) system will be the main diagnostic responsible for measuring the velocity distribution function of fusion-born alpha particles in the plasma. As the CTS diagnostic is integrated in the equatorial port plug 12 (drawer 3), with direct apertures to the port interspace where maintenance hands-on operation will be carried out, it is essential to assess the shutdown dose rates (SDDR) in these maintenance areas. In this work, the D1S-UNED3.1.4 Monte-Carlo transport code, based on the implementation of the direct-one-step methodology in MCNP5 v1.60, was used to estimate the dose rate level 12 days (106 s) after shutdown in the port interspace. The results show that the CTS system does not contribute significantly to the SDDR in the area where hands-on maintenance is foreseen with contribution to dose rates less than 1 µSv/h. This is consistent with previous estimates, although with the most recent model of the CTS design there is a slight increase of the SDDR values. This deviation can be attributed to design changes and improved shielding modelling and/or most importantly, to statistical fluctuations of the D1S simulations. From a neutronics point of view, the increase in the SDDR falls within the range of the statistical fluctuations, and the design is still compliant with the radiation safety ALARA principle aiming at minimizing radiation doses, and there is no requirement for further design optimizations.
Deep learning model inspired by lateral line system for underwater object detection
Authors: Jeong Taekyeong , Yoo Janggon , Kim Daegyoum
Published: December 2021

Inspired by the lateral line systems of various aquatic organisms that are capable of hydrodynamic imaging using ambient flow information, this study develops a deep learning-based object localization model that can detect the location of objects using flow information measured from a moving sensor array. In numerical simulations with the assumption of a potential flow, a two-dimensional hydrofoil navigates around four stationary cylinders in a uniform flow and obtains two types of sensory data during a simulation, namely flow velocity and pressure, from an array of sensors located on the surface of the hydrofoil. Several neural network models are constructed using the flow velocity and pressure data, and these are used to detect the positions of the hydrofoil and surrounding objects. The model based on a long short-term memory network, which is capable of learning order dependence in sequence prediction problems, outperforms the other models. The number of sensors is then optimized using feature selection techniques. This sensor optimization leads to a new object localization model that achieves impressive accuracy in predicting the locations of the hydrofoil and objects with only 40% of the sensors used in the original model.
Use, cost-effectiveness, and end user perspectives of a home solar lighting intervention in rural Uganda: a mixed methods, randomized controlled trial
Authors: Sundararajan Radhika , D’Couto Helen , Mugerwa Joseph , Tayebwa Mellon , Lam Nicholas L , Wallach Eli S , Wiens Matthew O , Ponticiello Matthew , Stanistreet Debbi , Tsai Alexander C , Vallarino Jose , Allen Joseph G , Muyanja Daniel , Shrime Mark G , Nuwagira Edwin , Lai Peggy S
Published: December 2021

Energy poverty is prevalent in resource-limited settings, leading households to use inefficient fuels and appliances that contribute to household air pollution. Randomized controlled trials of household energy interventions in low and middle income countries have largely focused on cooking services. Less is known about the adoption and impact of clean lighting interventions. We conducted an explanatory sequential mixed methods study as part of a randomized controlled trial of home solar lighting systems in rural Uganda in order to identify contextual factors determining the use and impact of the solar lighting intervention. We used sensors to track usage, longitudinally assessed household lighting expenditures and health-related quality of life, and performed cost-effectiveness analyses. Qualitative interviews were conducted with all 80 trial participants and coded using reflexive thematic analysis. Uptake of the intervention solar lighting system was high with daily use averaging 8.23 ± 5.30 h d−1. The intervention solar lighting system increased the EQ5D index by 0.025 (95% CI 0.002–0.048) and led to an average monthly change in household lighting costs by −1.28 (−2.52, −0.85) US dollars, with higher savings in users of fuel-based lighting. The incremental cost-effectiveness ratio for the solar lighting intervention was $2025.72 US dollars per quality adjusted life year gained making the intervention cost-effective when benchmarked against the gross domestic product per capita in Uganda. Thematic analysis of qualitative data from individual interviews showed that solar lighting was transformative and associated with numerous benefits that fit within a social determinants of health (SDOH) framework. The benefits included improved household finances, improved educational performance of children, increased household safety, improved family and community cohesion, and improved perceived household health. Our findings suggest that household solar lighting interventions may be a cost-effective approach to improve health-related quality of life by addressing SDOH.
Superior Nitrogen Fixing Bacteria Screening from Various Rhizobiome in Palm Oil Plantion, North Sangatta, East Kalimantan
Authors: Anggrainy Eka Dewi , Hidayati Arifah , Syarifain Roby Ibnu , Zulkarnain Muhammad Faizal Rezha , Simarmata Tualar
Published: December 2021

Nitrogen fixing bacteria (NFB) plays an important role in increasing N availability for plants. Research to examine the ability of nitrogen fixing bacteria isolates to produce nitrogenase, phytohormone and the ability of nitrogen fixing bacteria isolates in the biological test process using the corn plant indicator as an indicator has been carried out from September 2018 to February 2019 in laboratories and greenhouses. The ability of nitrogen fixing bacteria was tested by the ARA method, while the phytohormone testing of nitrogen fixing bacteria was tested using the HPLC method. Bioassays using Murphy media and corn plants as indicators were performed using a randomized block design consisting of six treatments (one control and five selected NFB isolates from the selection results) and given five replications. Measurement of root length, plant height, and dry weight of plants were carried out every 2 days for 14 days. The results showed that the nitrogen fixing bacteria isolates used from North Sangattarhizobiome, East Kalimantan had different nitrogenase and differentphytohormone test results, and obtained five selected isolates based on the selection results. The results of the bioassay did not show any significant differences based on the Duncan test at the level of 5%. However, it can be seen visually the significant difference in which plants in the biological test using nitrogen fixing bacterial isolates have relatively higher plant growth and dry weight of plants than plants that are not given treatment or control.
Rainfall trend analysis using Mann-Kendall and Sen’s slope estimator test in West Kalimantan
Authors: Aditya F , Gusmayanti E , Sudrajat J
Published: December 2021

Climate change has been a prominent issue in the last decade. Climate change on a global scale does not necessarily have the same effect in different regions. Rainfall is a crucial weather element related to climate change. Rainfall trends analysis is an appropriate step in assessing the impact of climate change on water availability and food security. This study examines rainfall variations and changes at West Kalimantan, focusing on Mempawah and Kubu Raya from 2000-2019. The Mann-Kendall (MK) and Sen's Slope estimator test, which can determine rainfall variability and long-term monotonic trends, were utilized to analyze 12 rainfall stations. The findings revealed that the annual rainfall pattern prevailed in all locations. Mempawah region tends to experience a downward trend, while Kubu Raya had an upward trend. However, a significant trend (at 95% confidence level) was identified in Sungai Kunyit with a slope value of -33.20 mm/year. This trend indicates that Sungai Kunyit will become drier in the future. The results of monthly rainfall analysis showed that significant upward and downward trends were detected in eight locations. Rainfall trends indicate that climate change has occurred in this region.
The Regional Hadley Cells Response to the Sea Surface Temperature Distribution Across the Indo-Pacific Ocean
Authors: Fatmasari D
Published: December 2021

Hadley Cells are thermally driven cell in the tropics. On its occurrence, these cells are strongly influenced by the sea surface temperature (SST) distribution across the tropical ocean or the Pacific Ocean as the investigated location in this study. The SST shifting in the Pacific Ocean is mainly due to the ENSO. An opposite SST polarity between the western and eastern Pacific Ocean are captured during ENSO events. This means that ENSO could trigger an anomalous regional Hadley Cells that behave oppositely between Indonesia or the western Pacific and the eastern Pacific. This study examines the strength of the regional Hadley Cells related to the ENSO event across the Indonesian region and the Pacific Ocean. A significant correlation between the Hadley Cells and ENSO as the tropical climate variability in the Pacific Oceans are found. The strength of the Hadley Cells associated with ENSO event is examined by using the zonally average vertical velocity across the Pacific Ocean. During La Nina, the regional Hadley Cells over Indonesia or the western Pacific strengthened, whereas the regional cells over the eastern Pacific weakened. In contrast, during El Nino where the warm pool shifted to the eastern Pacific, the regional cell in the eastern Pacific strengthened, while the cell over the western Pacific weakened. These anomalous conditions clearly show that the meridional temperature gradient is strongly affecting the regional Hadley Cells strength. The stronger the meridional temperature gradient, the stronger the regional Hadley Cells.
Spatio-Temporal Lightning Analysis Over North Sulawesi in 2019 - 2020
Authors: Azani A A , Pratama D A , Kusumawardani N , Rusmala I , Septiadi D
Published: December 2021

This study aimed to analyze the spatial and temporal lightning distribution in North Sulawesi. The general meteorological condition of North Sulawesi has also been considered to identify the cause of the lightning occurrence. Lightning activity over North Sulawesi has been investigated using lightning data from Winangun Geophysical Station during 2019-2020. The result shows that in the land area of North Sulawesi, the highest lightning density occurred in the Tomohon regions due to its topographical features. Overall, the flash density over the land area is higher than the sea area due to its high atmospheric instability. The maximum flash density does not occur during the wet periods, but it occurs during September - October – November, which has a high surface temperature over this region. It is also known that shearline and low-pressure areas contribute to the high lightning occurrence in October 2019, while La Nina in the Pacific Ocean influences lightning activity in July 2020
The Determination of Rainfall Threshold Triggering Landslides Using Remote Sensing
Authors: Agustina L , Safril A
Published: December 2021

Landslide is one of the natural disasters that can cause a lot of loss, both material and fatalities. Banjarnegara Regency is one of Central Java Province regencies where landslides often occur due to the region's topography and high intensity rainfall.. Therefore, it is necessary to determine the threshold of rainfall that can trigger landslides to be used as an early warning for landslides. The rainfall data used for the threshold is daily and hourly rainfall intensity from remote sensing data that provides complete data but relatively rough resolution. So that remote sensing data need to be re-sampled. The remote sensing data used is CMORPH satellite data that has been re-sampled for detailing existing information of rainfall data. The resampling method used is the bilinear method and nearest neighbor by choosing between the two based on the highest correlation. Threshold calculation using Cumulative Threshold (CT) method resulted equation P3 = 7.0354 - 1.0195P15 and Intensity Duration (ID) method resulted equation I = 1.785D-0305. The peak rainfall intensity occurs at the threshold of 97-120 hours before a landslide occur.
Analysis of variability and projection of extreme rainfall in West Java
Authors: Hutauruk R C H , Amin T , Irawan A M
Published: December 2021

This research discusses the effect of climate change on extreme rainfall in West Java using the RCP 4.5 and RCP 8.5 scenarios by comparing daily rainfall data with model ACCESS-1, CSIROMK3.6 model, MIROC-5 from NASA Earth Exchange Global Daily Downscaled Projection (NEX-GDDP) and the ensemble of three models each season with Extreme Dependency Score (EDS) method. This study projects an extreme rainfall index of 30 years (2011-2040). The three extreme rainfall indices issued by the Expert Detection Team and the Climate Change Index (ETCCDI) consisted of Rx1day, R50mm, and R95p used in this study. The results showed that the projection period (2011-2040) used RCP 8.5 which had a trend of increasing extreme rain index that was greater than RCP 4.5. For RCP 8.5 the maximum rainfall will increase in Indramayu, Majalengka, Purwakarta, Sukabumi and Ciamis areas. Increased rainy days occurred in Bogor, Bekasi, Karawang, Purwakarta, Bandung, Sumedang, Majalengka, Cirebon, Indramayu. Extreme rainfall will increase in Bekasi, Karawang and Bogor regions.
Spatiotemporal variation of mesoscale convective system type persistent elongated convective system (PECS) in Indonesia
Authors: Firdaus I M , Trilaksono N J
Published: December 2021

Research on Mesoscale Convective Systems (MCS) in Indonesia has been studied to identify the characteristics and distribution of MCS. Persistent Elongated Convective System (PECS) is one of the MCS types that can cause extreme weather. However, identifying the spatial and temporal variations of PECS in Indonesia has not been studied further. This study examines the Persistent Elongated Convective System (PECS) in Maritime Continent from 2010-2014. MERG Dataset with brightness temperature is used to identify PECS and input Grab ‘Em Tag ‘Em Graph ‘Em (GTG) tracking algorithm to gain a better understanding of spatiotemporal variation in Indonesia. Flood data from BNPB in Indonesia is used to find out the correlation between flood and PECS events in Indonesia. PECS events in 2010-2014 are 5574 events, which the transitional period (MAM and SON) has the most PECS events and longest duration of life. The PECS spread in the early morning on land and sea, while on day and nighttime, it is concentrated on land for the area of Java, Papua, and Southern Kalimantan. Java and Papua have the largest concentrated PECS events. The life phase of the PECS has two peaks or semidiurnal cycles, in the morning and nighttime. There are differences in peak times for each phase of the PECS on land and sea. In Indonesia, PECS has the smallest average maximum area than in the USA and China but has the longest duration and largest eccentricity. Based on flood data from BNPB, during 2010-2014, Java has the most flood. According to flood data and PECS events in Java, there is 6.72% of flood coincided with PECS events during the period.
The characteristics of the equatorial waves caused a record torrential rain event over western Sumatra
Authors: Wu P , Fukutomi Y , Kikuchi K
Published: December 2021

This study examined the cause of a record torrential rain event over the western coast of Sumatra Island in March 2016. The influence of atmospheric equatorial waves (EWs) and the characteristics of the EWs were investigated. Analysis of the Japanese 55-year Reanalysis data (JRA-55) and precipitation data from the Global Precipitation Measurement (GPM) satellite showed that the event was caused by the combined effects of Kelvin waves, equatorial Rossby waves, and westward inertio-gravity (WIG) waves. An examination of the characteristics of the EWs revealed that the Kelvin waves had longitudinal scales of ~6,000 km, with a period of ~6 days and phase speed of ~12 m s-1, which was typical of the convectively coupled Kelvin waves in this region. The WIG waves had a scale of ~2,500 km, with a period of 2.5 days and a relatively fast phase speed of 12~13 m s-1. Heavy precipitation occurred when an eastward Kelvin wave from the Indian Ocean encountered a westward inertio-gravity (WIG) over Sumatra Island. It was concluded that along with the Kelvin and equatorial Rossby waves, the WIG waves might have played a major role in the formation of the extreme precipitation event.