bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of An Intelligent Demodulation Method for X-ray Spectrum Communication
Authors: Gao Youtao , Dong Guocang , Jin Limin
Published: March 2023

X-ray communication based on X-ray spectrum modulation information is a novel communication method, which can effectively improve communication ability and anti-interference ability. In this paper, four characteristic X-rays are chosen to modulate information. The influence of channel attenuation, random noise in space, and miss-shooting rate caused by adjacent targets are discussed. Based on error-correcting output codes and a 10-fold cross-validation method, a neural network intelligent classifier is designed to realize intelligent information demodulation. Simulation results show that if the miss-shooting rate is lower than 0.4 and the photon retention rate after channel attenuation is higher than 0.0008, then the classifier can achieve a recognition success rate of more than 99%. This study provides reliable index requirements for the performance of the four-target material source equipment to be designed next. This paper also provides a theoretical basis for the subsequent further realization of space communication capabilities.
An Improved Segmented MTI Filter Based on a Clustering Algorithm
Authors: Liao Jiahao , Liu Shan
Published: March 2023

A K-Means clustering algorithm modified MTI (Moving Target Indication) filter is proposed for refining signal processing of the array environment in response to the current demand for clutter suppression by array adaptive technology. The method first uses the clutter distribution type and distance as parameters of the K-Means clustering algorithm to divide the echo’s into different clutter distance segments. Then an adaptive MTI filter is used to filter each clutter distance segment separately. The identification was carried out using measured ground radar echo data. The results show that the k-means clustering algorithm has better clutter distance segmentation capability. Compared with the conventional two-pulse MTI filter, the improved segmented MTI filter of the k-means algorithm has better clutter suppression in complex clutter environments.
Research on the evaluation method of the performance of hydraulic transmission oil
Authors: Xu Wanli , Wang Changfu , Wang Xudong , Wang Mengyi , Chen Jinmao
Published: March 2023

The characteristics of hydraulic transmission oil directly affect the performance of ground equipment. The current evaluation method of hydraulic transmission oil is mostly focused on its physical and chemical performance analysis, which cannot meet the actual needs of the equipment. This paper carried out research work for the evaluation method of hydraulic transmission oil, starting from its working principle and then designing a hydraulic transmission oil performance evaluation bench. It proposed evaluation indexes and evaluation methods, which are of reference significance for the selection of oil for equipment and promoting oil development.
A prediction method of remaining useful life of water pump equipment based on 1D-CNN-LSTM
Authors: Pan Jian , Li Yujiang , Zhao Huandong
Published: March 2023

This paper presents a prediction method for the remaining useful life of water pump equipment based on 1D-CNN-LSTM neural network. Firstly, the vibration signals of the body, base and drive end of the water pump equipment are collected and the time-frequency domain information is extracted from the vibration signals. Input samples are built using the extracted information, inlet, outlet pressure, and flow. Then, a one-dimensional convolutional neural network is added in front of the short-term memory neural network to get a better prediction of the remaining remaining life of the pump equipment. Finally, the time domain information, frequency domain information, flow rate of the vibration signal, inlet pressure, and outlet pressure are used for prediction experiments. Then the prediction results of different prediction models are compared, which proves the effectiveness of the proposed method in predicting the remaining useful life.
Four-Function Fully Automatic Refrigerator Protection System Design
Authors: Shi LuLu , Zhang Bo , He RuiLong , Zhao YuGe
Published: March 2023

In the automatic refrigerator protection system hardware design, the MCU is selected as the core control of the system, the specific design content includes the selection of the automatic refrigerator protection system design scheme, MCU, and sensor types and models, in addition, it is necessary to combine the components of the display module design; In the system software design, the most core content is the system program design. The system collects the undervoltage, overvoltage, power failure, leakage, and other conditions of the power supply refrigerator, and the control switch is automatically disconnected to protect the refrigerator. C language was chosen to design the system software code, and Proteus software was used to realize the system function simulation, and the functions of the system were verified.
Interaction Strategy Between the Vehicle-station-grid Considering Privacy Protection
Authors: Xi Yanjun , Yang Jinglu , Zhang Xuze , Ji Yang , Wang Qiang , Shi Hang
Published: March 2023

The number of electric vehicles (EVs) is increasing daily, and the charging demand for large-scale EVs has a greater impact on the distribution network, so it is urgent to study the cooperative interaction optimization strategy of the “EV-charging station-distribution grid.” In this paper, we take the charging load of EVs in the regional distribution network as the research object. We establish a multi-intelligence reinforcement learning-based optimization strategy for the interaction between EVs and the grid to obtain the optimal charging decision to minimize the peak-to-valley difference between the user-side economy and the grid-side load. The results show that the proposed EV-grid interaction optimization strategy can effectively reduce the peak-to-valley difference in charging station load and realize the efficient cooperative interaction of the “vehicle-station-grid.”
Study on the Crashworthiness Performance of A Cargo Hold Support Column of A Civil Aircraft
Authors: Yang Guiqiang , Yin Weiming , Wang Yi
Published: March 2023

With the continuous development of China’s general aviation industry, there are urgent requirements for research on aircraft crashworthiness to provide better safety for aircraft occupants. According to the results of long-term crash investigations, if crash safety design is taken into account at the earliest stages of aircraft design, most accidents will become viable or partially survivable, which can greatly improve the survival rate of aircraft passengers after an accident. In this paper, the design criteria and design methods for crash resistance technology of aircraft cargo uphold pillars are studied, and the crash simulation analysis of a certain type of aircraft is analyzed. First, a feasible design method and optimization principle are formulated according to the specific characteristics of a certain type of aircraft; Then, the crash resistance characteristics of a certain type of aircraft are analyzed, and the finite element model of the fuselage and cargo uphold pillars structure is established based on the three-dimensional electronic prototype of the aircraft. By the crash conditions specified in the relevant specifications, a mechanical simulation study of the aircraft is carried out, and the results are analyzed. Finally, constructive comments are given based on the simulation results. The reliability of the design is verified using simulation analysis, which provides a reference for the simulation and analysis of the anti-crash design of the aircraft cargo uphold pillars structure.
Analysis of the Method and Principle of Measuring the Average Power of Equipment Based on DC Power Analyzer
Authors: He Yalei , Zhang MingJie , Yuan HongXue , Wen XueJun , Zhao YuHui
Published: March 2023

To solve the problem that it is difficult to accurately measure the average power of equipment with large instantaneous power change, this paper analyzes the principle of equipment power change and the mechanism of measurement error and proposes a reliable average power measurement method based on the idea of calculus. Through test verification, compared with the common three-measurement average methods, the uncertainty of the results calculated by the method proposed in this paper is reduced, and the results are accurate and reliable, which can reflect the real power of the equipment and meet the requirements of the test and test support.
Evaluation of electric vehicle charging facilities by using the MCDM method
Authors: Li Yanbin , Jia Junguo , Wu Shangjie , Guo Sen
Published: March 2023

As one of the candidate carriers of future transportation, electric vehicles are widely considered an important choice to solve traffic derivative problems and environmental issues. In this paper, the evaluation of electric vehicle charging facilities is studied by employing the MCDM method. The fuzzy BWM was utilized to weight the criteria, and the MARCOS method was employed to evaluate different electric vehicle charging facilities. Eight criteria for electric vehicle charging facilities were determined, and five electric vehicle charging facilities were evaluated by using the hybrid MCDM method. The empirical results indicate that the comprehensive performance of electric vehicle charging facility EVCF#5 is best, followed by EES#3, EES#2, and EES#1, while the electric vehicle charging facility EES#4 has the worst comprehensive performance. This research can provide references for the sustainable development of electric vehicle charging facilities.
Short period Wind Power Forecast Method Based on Maximum Correntropy Criterion
Authors: Liu Jing , Zheng Xin , Wang Wenhai , Pan Zhiyuan , Wang Jing , Zhang Lei , Li Haifeng
Published: March 2023

Wind power forecast is an essential measure to increase the level of wind velocity consumption and also the basis of wind power dispatching operations. In the cause of increasing the precision of short-period wind velocity forecast, this srticle adopts a new evaluation criterion(MCC) in order to direct optimization of the parameters of the wind power model. The method first filters and normalizes the measured historical data and determines the optimal input variable dimension through a set of fixed parameters. Then, grid optimization and Particle Swarm Optimization (PSO) are used as evaluation criteria for parameter optimization. Finally, the obtained optimal parameters are used to forecast the short-term wind power, and four evaluation indexes are used to evaluate the forecasting results. The results show that the parameter optimization process using MCC as the evaluation criterion is more suitable for wind power output characteristics, and comparing with traditional optimisic methodthe the forecast accuracy is increased by 5 -10%.
Evaluation method of power loss for distribution network fault handling based on distribution transformer outage and restoration information matrix
Authors: Lin Dongyue , Zhang Wei
Published: March 2023

To solve the problem of power loss evaluation in distribution network fault handling, an evaluation method of power loss for distribution network fault handling based on distribution transformer outage and restoration information matrix is proposed. Firstly, the distribution transformer outage and restoration information matrix model is established to describe the distribution transformer, its outage time, its restoration time, its outage duration, and its lost power affected by the distribution network failure outage. Then the outage duration in the process of fault handling is discussed in four cases, and the detailed calculation formula is given. At last, the power loss of a single distribution transformer, the total power loss of distribution network failure, and the average power loss of a distribution transformer are described in detail by outage time and predicted power. The example analysis shows that this method can quickly estimate the power loss of a distribution transformer in the process of fault disposal, and the method is simple and reliable, which can meet the needs of field applications and has good promotion value.
Research on Knowledge Graph-based Fault Diagnosis Method for Substation Equipment Operation
Authors: Zhang Ming , Huang Cheng , Li Wenguang , Sun Wei , Liu Zhuo
Published: March 2023

The current image processing-based fault diagnosis method for substation equipment operation realizes fault diagnosis by monitoring the thermal status of the equipment, which leads to low diagnostic accuracy due to the lack of analysis of alarm signals. In this regard, the research of substation equipment operation fault diagnosis method based on knowledge mapping is proposed. A fault diagnosis model is established by building a behavior map of substation accident-like alarm signals, analyzing the alarm behavior as well as the causes of faults, and predicting the posterior probability of faults. In the experiment, the diagnosis accuracy of the proposed method is verified. The analysis of the experimental results shows that the fault diagnosis model constructed by the proposed method has good diagnostic performance and high diagnostic accuracy.
A New technology of transformer bushing state detection based on transient dielectric response
Authors: Sun Lei , Zhang Lu , Jing Feng , Ma Li , Wang Wensen , Jin Jiandong
Published: March 2023

Failure of the transformer bushing will cause the transformer to be powered down or damaged, affecting the safe operation of the power system. This paper proposes a method using system harmonics as the dielectric response excitation source and studies the transformer bushing insulation online detection technology based on transient dielectric response characteristics. The technical scheme and system structure of the online monitoring technology of transformer bushing insulation based on dielectric response characteristics are given. A calculation model of short-circuit grounding and capacitor switching of a 35kV substation was established, and the harmonic frequency content and amplitude distribution of grid disturbance were analyzed. A case of dielectric response measurement of the bushing is given. The research shows that the system will generate overvoltage in short circuit grounding, capacitor switching, etc. The system harmonic frequency is in the range of the dielectric response test frequency band (1Hz~1kHz), and the harmonic amplitude is also large, which can be used as an excitation source. The excitation source of the dielectric response test causes a change in the dielectric response of the transformer bushing and acts as a “probe” that reflects the insulation state of the bushing. The medium and high-frequency bands of the dielectric spectrum in the frequency domain are also sensitive to moisture, which can be used to diagnose the insulation state of the bushing.
Research on the angular velocity estimation method based on the state augmentation method
Authors: Yan Zewei , Yang Haiyan , Qi Ji
Published: March 2023

In the maneuvering target tracking research due to the unpredictability of the target’s maneuvering, it makes it difficult to establish an accurate target motion model to reflect the real motion trajectory of the target. Based on the determination of the parametric maneuver model and the radar measurement conditions of the target, the joint estimation method of the motion state and the maneuver parameters is designed to obtain the optimal estimation of the motion state and the maneuver parameters based on the optimal evaluation criteria. Currently, in the descriptive category of the state space model, the state augmentation method is obtained to solve the joint estimation of the motion state and maneuver parameters based on the estimation criterion [1]. Therefore, the angular velocity estimation method of the state augmentation method is used to consider the estimated value of the target angular velocity and the estimated variance comprehensively to improve the convergence speed of target tracking, minimize the error between the filtered angular velocity and the real angular velocity of the maneuvering target, and finally achieve the purpose of improving the target tracking accuracy.
Radar Communication Jamming Signal Recognition Based on the Attention Mechanism
Authors: Li Yuanyuan , Lu Yawei , Tong Xihe
Published: March 2023

In modern battlefields, radar radiation sources detect targets by transmitting high-power modulated signals. In order to protect the operational effectiveness of the radar, there is a higher requirement for radar communication anti-jamming signal recognition capability. The accurate and fast identification of radar anti-jamming signals is the prerequisite for taking effective anti-jamming measures, which will directly affect the operational effectiveness of radar. At present, the recognition method based on the neural network can automatically extract signal features and obtain good recognition results. Because radar emitter signals have a strong correlation in time sequence, the LSTM network is used in this paper. For better feature extraction and classification of signals, this paper constructs the LSTM attention network, combines the attention mechanism with the LSTM recognition network, and proves the effectiveness of radar communication jamming signal recognition network based on the attention mechanism through experiments.
Giant Magneto-Impedance Effect Microcurrent Sensor Based on MEMS Technology
Authors: Liu Siyuan , Wang Tao , Luo Yufeng
Published: March 2023

The performances of common magnetic sensors in the field of microcurrent detection are presented. The giant magneto-impedance (GMI) effect is summarized, and the possibility of picoampere microcurrent measurement using the GMI effect sensor is proved. The classical design scheme of the GMI effect current sensor is improved, and a GMI sensor chip model that can realize picoampere microcurrent measurement is preliminarily established, which lays a theoretical foundation for further development of GMI microcurrent sensor with high performance, small volume, and low cost.
Optimization design of feed array structure for space-borne synthetic multi-beam antenna
Authors: Xue Zhaoxuan , Zhang Xingang , Wan Jian , Liu Xi , Hou Jian
Published: March 2023

To reduce the difficulty of engineering realization as much as possible on the premise of ensuring the performance of the feed network, a new design method of the multi-feed composite multi-beam antenna feed array is proposed. In the design process, the method of longitudinal subdivision and layering is used to solve the processing problem of complex large-scale electrical and small-sized devices. Then the multi-objective and multi-variable differential evolution algorithm is used to optimize the distribution position of each mounting hole to realize the optimal interface layout. The method is used to optimize the design of a multi-beam antenna feed array and the product object is produced and tested. The test results show the effectiveness of the design method. This method can be used to guide designers to carry out actual engineering design, shorten the design cycle, and improve the design quality.
Research on identification method of weak links in transmission network considering strong wind in severe cold weather
Authors: Zhuang Guanqun , Wang Weichen , Li Dexin , Gao Song , Wang Changjiang
Published: March 2023

The ice disaster has brought many adverse effects on the power transmission system, which is mainly studied from the transmission line failure rate perspective. Strong winds often accompany the ice disaster weather, the motion path of wind is considered when identifying the weak location of transmission network system. According to the theory of meteorological simulation, and the mathematical relationship between the effective wind speed and the forced outage rates is obtained. A transient stability risks assessment method is proposed considering the ice disaster in the case of a strong wind moving path. According to the fault probability of transmission lines, a predictive fault set for power grid risk assessment is established. The IEEE-39 bus system is used as an example to analyze the effectiveness of the proposed method. The simulation results show that meteorological parameters, geographical environment, and other factors, especially the meteorological advance speed and the direction of transmission lines, will cause greater damage to the stability of the transmission system.
Hydraulic System Design and Simulation of the Lifting Device for the Hanging Barrel Campus Garbage Truck
Authors: Fei Lilin , Qiao Xun , Zhang Shaoguo
Published: March 2023

According to the parameters of the Chengliwei CLW5165ZZZD5 garbage truck, the hydraulic system of the lifting device is designed and simulated. Firstly, the working pressure of the hydraulic system is calculated, and then the type of hydraulic components required is designed and selected; Secondly, the hydraulic system sketch is established through AMESim software and the parameter simulation is carried out; Finally, the variation law of pressure, flow, speed, displacement and other parameters of the hydraulic cylinder is analyzed. The results show that the lifting device can make the Chengliwei self-loading garbage truck work normally, and the design requirements meet the working requirements.
Numerical Control Simulation and Programming Based on SinuTrain Bearing Bracket (Five-axis)
Authors: Jin Weiwen , Lei Tongfei
Published: March 2023

At present, the development of numerical control processing technology has entered a new period and has gradually developed in the direction of artificial intelligence. Along with the development of science and technology in recent years, the present stage of our country has made a significant breakthrough in the application of numerical control processing technology. Hence, learning to master CNC machining technology is necessary. Numerical control simulation software is used to NC machining the bearing bracket (five-axis), and numerical control simulation software SinuTrain is used to NC programming the parts and simulation verification of the machining process. SinuTrain is a CNC training software that functions exactly like the controller itself. The use of this software for bearing bracket (five-axis) numerical control simulation and programming, can make us master the use of this software, and can also help us understand the mechanical processing process and programming technology.
Design of Running in Control Platform for Tracking Turntable
Authors: Li Qianrong , Qi Le
Published: March 2023

The tracking turntable is an important device in a laser digital sight. In the normal operation of the sight, the flatness and smoothness of the turntable are the necessary conditions for the stable operation of the system. In this paper, for the problem of improving the operation accuracy of the turntable, a set of special processes and equipment is developed through the electrical and structural design. After the processing, the control box runs the turntable for a certain time, which can remove the tooth height and burr, and improve the transmission stability and transmission accuracy.
The choice of degrees of freedom of automatic refueling manipulator
Authors: Tao Chen , Fang Xie , Li Mahong
Published: March 2023

Traditional artificial gas station come on all the required 5 to 6 minutes, peak even 10 minutes or so, along with our country automobile holdings continued to increase, how to improve fuel efficiency become an important problem of gas station, according to the above problem, non-inductive refueling “AI” is put forward to cooperate with mechanical arm instead of artificial gas, this scheme can make the refueling time reduced to 3 minutes, Greatly improve refueling efficiency, and reduce labor costs. The manipulator adopts a tandem joint robot with a 2-DOF BB wrist at the wrist and a fixed base, which is driven by the servo motor of each joint as a whole. The end-effector is equipped with a cap opening device, a clamping device and an oil feeding device to open the oil tank cover, unscrew the seal plug and oil feeding tasks respectively.
Failure Analysis and Improvement of Check Valve Reverse Cut-off Seal
Authors: Li Lei-lei , Zhao Jian , Gong Sheng-bo , Liu Bao-rong , Zhang Hao , Zhou Xiao-lei , Miao Li-lei , Li Peng
Published: March 2023

Given the failure of reverse cut-off seal performance in the test process of the check valve, the fault location and mechanism analysis were carried out, and the improvement measures were proposed and verified by the test. It is analyzed that the main reason for the failure is the unreasonable design of the moving pair and the welding position of the check valve, which makes the sealing pair cannot fit effectively after the welding of the check valve, leading to the failure of the reverse cut-off seal. By controlling the ratio of the length of the guide surface to the diameter of the guide surface to 1.25, and controlling the distance between the welding position and the sealing pair to 10mm, the failure problem of the reverse cut-off seal of the check valve caused by the unreasonable design of the moving pair and the weld position is successfully solved. The effectiveness of the improved scheme of the check valve is verified by the test.
Research on Acceleration Segmented Compensation Strategy for Backlash of CNC Machine Tools
Authors: Zhang Qiujie , Shen Huiming , Qin Xiufeng , Lü Tianguo
Published: March 2023

For the problem of backlash in the semi-closed-loop linear feed servo system of CNC machine tools, which seriously affects the accuracy of machine tools, an acceleration segmentation backlash compensation strategy is proposed. In the reverse motion of the servo motor, the servo motor is controlled to compensate for the backlash error during a period of accelerated motion and a period of decelerated motion. Based on the established backlash transmission model, the parameters of the compensated motion process are calculated. In order to ensure accurate and quick compensation of the gap compensation value for the transmission gap, the backpropagation method is used to backpropagate the acceleration calculation based on whether the acceleration process time is an integer multiple of the servo interpolation period. Finally, the feasibility of the method is verified through experiments, and the results show that the method improves the positioning accuracy of machine tools.
Single Image Dehazing Based on Contrastive Learning and Transformer
Authors: Zhao Yang , Wang Yigang
Published: March 2023

For the single image dehazing problem, an end-to-end multi-stage dehazing algorithm is designed. The algorithm contains two distinct parts to extract features. For shallow features, texture-level information is mined by stacking pixel and channel attention mechanisms. The proposed method uses multi-head self-attention (MHSA) to capture high-level features. MHSA improves dehazing performance by mining the dependencies of a wide range of abstract information. The superiority of the transformer architecture is extended with cascaded attention mechanisms and convolutions to improve feature extraction capabilities. Multilayer perceptron (MLP) is used in the decoding stage to equalize the context information. Furthermore, a contrastive loss function that introduces multiple negative samples and correction terms is proposed. The correction term is generated according to the difference between the precise and blurred images, which can enhance the training effect when dealing with different concentrations of dehaze. The training result of this loss function assists the model in approximating clear images and staying away from blurry images. According to the experimental results compared with other methods under the same conditions, the proposed method achieves good results in both subjective visual effects and objective evaluation indicators. The proposed contrast loss function also improves the dehazing performance of the algorithm.
Research on Classification and Recognition of Industrial Stainless Steel Welded Pipe Defects Based on Convolution Neural Network
Authors: Wang Zongren , Zhu Liujuan , Hou Huaishu , Liu Luyu
Published: March 2023

For the classification and identification of industrial stainless steel welded pipe defects, a combined method of STFT and CNN based on vortex test is proposed. First, the collected original eddy current signal is STFT transformed to obtain a two-dimensional time-frequency map. Then, the two-dimensional time-frequency map was input into the two neural networks VGG-16 and GoogLeNet for model training, selecting a more accurate network model under the condition of the same learning rate. The trained network model is then classified using different learning rates. The results show that with the learning rate of 0.0001, the VGG-16 training model is better than the GoogLeNet training model, which has a certain reference significance for the classification and identification of defects in industrial stainless steel welded pipes.
Research strategy of fault diagnosis considering WOA-VMD algorithm
Authors: Huang Dayang
Published: March 2023

To address the problem of low accuracy of fault information extracted from motor-bearing vibration signals, a feature extraction method based on Whale Optimization Algorithm (WOA)-Variable Modal Decomposition (VMD) energy entropy is proposed, and a modified WOA-Support Vector Machine (SVM) is used for fault diagnosis. Firstly, the optimal number of modes K and penalty parameters α for the variable modal decomposition are found by WOA. WOA is used to find Then a number of modal components are obtained based on the VMD processing signal, and the energy entropy is further extracted as the feature vector after screening. Finally, to address the shortcomings of the WOA population iteration mechanism, a random variation strategy is introduced to improve the WOA-SVM for fault diagnosis of bearing signal. The results show that the WOA-VMD method can decompose the bearing fault information from the current signal and overcome the problems of modal confusion and pseudo-component of the EMD method, which is an effective method to deal with rolling bearing faults. Meanwhile, this method has been verified by experiments show can accurately extract the fault information and improve the fault identification rate of motor-bearing data with an accuracy of 99.2%.
Jetting Velocity Prediction for Piezoelectric Ejection System Based on GA-BP
Authors: Xinli  , Zhao Yongsheng , Niu Nana , Chen Kui
Published: March 2023

Droplet jetting velocity is one of the most important factors affecting the quality of piezoelectric ejection printing. Due to the nonlinear relationship between the two, predicting the droplet jetting velocity by conventional methods is very time-consuming and impractical. We propose a genetic algorithm (GA) combined with a back propagation neural network (BPNN) to predict the droplet jetting velocity. The network topology and the values of each parameter of the model are designed and validated to elucidate the relationship between the input parameters of the piezoelectric ejection system and the studied droplet ejection velocity. The GA-BP model was trained, tested, and tuned using a database consisting of data generated from finite element calculations, and the results showed an error of 3.34% between the predicted and finite element simulated droplet ejection velocities, which demonstrates the reliability and robustness of the method.
3D printing of inorganic scintillator-based particle detectors
Authors: Sibilieva T. , Alekseev V. , Barsuk S. , Berns S. , Boillat E. , Boiaryntseva I. , Boyarintsev A. , Carbone A. , De Roeck A. , Dolan S. , Driuk T. , Gendotti A. , Gerasymov I. , Grynyov B. , Hugon S. , Kose U. , Opolonin O. , Rubbia A. , Sgalaberna D. , Sibilyev M. , Tretyak S. , Weber T. , Wuthrich J. , Zhao X.Y.
Published: March 2023

Inorganic scintillators are widely used for scientific,
industrial and medical applications. The development of 3D printing
with inorganic scintillators would allow the fast creation of
detector prototypes for the registration of ionizing radiation, such
as alpha, beta and gamma particles in thin layers of active
material, and X-ray radiation. This article reports on the technical
work and scientific achievements that aimed at developing a new
inorganic scintillation filament to be used for the 3D printing of
composite scintillator materials: study and definition of the
scintillator composition; development of the methods for the
inorganic scintillator filament production and further
implementation in the available 3D printing technologies; study of
the impact of the different 3D printing modes on the material
scintillation characteristics. Also, 3D-printed scintillators can be
used to produce combined detectors for high-energy physics.
Evaluation of the timing performance of the DIET ASIC
Authors: Lang Zijian , Deng Z. , Gong H.
Published: March 2023

DIET is a 64-channel SiPM readout ASIC for TOF-PET and can
measure energy and arrival time independently for each channel. With
the increasing requirements for time measurement precision, the
timing performance of the DIET chip has been fully evaluated in this
paper. The noise sources in the time processing chain, especially in
the TDC, were theoretically analysed, and a dedicated test system
was built. The time jitter of the analogue front end and the TDC
were measured and analysed. The test results show that the total
jitters of the analogue front-end and the TDC are 24 ps and 22 ps
RMS at 50 p.e. input signal, respectively. The percentages of the
contribution by INL, thermal noise, and quantization noise of the
TDC are 70%, 16.6%, and 13.4%, respectively. The DIET chip was
also tested with SiPM and LYSO detectors. A CRT resolution of
244 ps FWHM was achieved using two single
3 × 3 × 16 mm3 crystals.
A virtuous cycle between invertebrate and robotics research: perspective on a decade of Living Machines research
Authors: Mangan Michael , Floreano Dario , Yasui Kotaro , Trimmer Barry A , Gravish Nick , Hauert Sabine , Webb Barbara , Manoonpong Poramate , Szczecinski Nicholas
Published: March 2023

Many invertebrates are ideal model systems on which to base robot design principles due to their success in solving seemingly complex tasks across domains while possessing smaller nervous systems than vertebrates. Three areas are particularly relevant for robot designers: Research on flying and crawling invertebrates has inspired new materials and geometries from which robot bodies (their morphologies) can be constructed, enabling a new generation of softer, smaller, and lighter robots. Research on walking insects has informed the design of new systems for controlling robot bodies (their motion control) and adapting their motion to their environment without costly computational methods. And research combining wet and computational neuroscience with robotic validation methods has revealed the structure and function of core circuits in the insect brain responsible for the navigation and swarming capabilities (their mental faculties) displayed by foraging insects. The last decade has seen significant progress in the application of principles extracted from invertebrates, as well as the application of biomimetic robots to model and better understand how animals function. This Perspectives paper on the past 10 years of the Living Machines conference outlines some of the most exciting recent advances in each of these fields before outlining lessons gleaned and the outlook for the next decade of invertebrate robotic research.
Hybrid modeling of evapotranspiration: inferring stomatal and aerodynamic resistances using combined physics-based and machine learning
Authors: ElGhawi Reda , Kraft Basil , Reimers Christian , Reichstein Markus , Körner Marco , Gentine Pierre , Winkler Alexander J
Published: March 2023

The process of evapotranspiration transfers liquid water from vegetation and soil surfaces to the atmosphere, the so-called latent heat flux (

Q

LE

), and modulates the Earth’s energy, water, and carbon cycle. Vegetation controls

Q

LE

by regulating leaf stomata opening (surface resistance

r

s

in the Big Leaf approach) and by altering surface roughness (aerodynamic resistance

r

a

). Estimating

r

s

and

r

a

across different vegetation types is a key challenge in predicting

Q

LE

. We propose a hybrid approach that combines mechanistic modeling and machine learning for modeling

Q

LE

. The hybrid model combines a feed-forward neural network which estimates the resistances from observations as intermediate variables and a mechanistic model in an end-to-end setting. In the hybrid modeling setup, we make use of the Penman–Monteith equation in conjunction with multi-year flux measurements across different forest and grassland sites from the FLUXNET database. This hybrid model setup is successful in predicting

Q

LE

, however, this approach leads to equifinal solutions in terms of estimated physical parameters. We follow two different strategies to constrain the hybrid model and therefore control for the equifinality that arises when the two resistances are estimated simultaneously. One strategy is to impose an a priori constraint on

r

a

based on mechanistic assumptions (theory-driven strategy), while the other strategy makes use of more observational data and adds a constraint in predicting

r

a

through multi-task learning of both latent and sensible heat flux (

Q

H

; data-driven strategy) together. Our results show that all hybrid models predict the target variables with a high degree of success, with

R
2

= 0.82–0.89 for grasslands and

R
2

= 0.70–0.80 for forest sites at the mean diurnal scale. The predicted

r

s

and

r

a

show strong physical consistency across the two regularized hybrid models, but are physically implausible in the under-constrained hybrid model. The hybrid models are robust in reproducing consistent results for energy fluxes and resistances across different scales (diurnal, seasonal, and interannual), reflecting their ability to learn the physical dependence of the target variables on the meteorological inputs. As a next step, we propose to test these heavily observation-informed parameterizations derived through hybrid modeling as a substitute for ad hoc formulations in Earth system models.
Unitary matrix integrals, symmetric polynomials, and long-range random walks
Authors: Vleeshouwers Ward L , Gritsev Vladimir
Published: March 2023

Unitary matrix integrals over symmetric polynomials play an important role in a wide variety of applications, including random matrix theory, gauge theory, number theory, and enumerative combinatorics. We derive novel results on such integrals and apply these and other identities to correlation functions of long-range random walks (LRRW) consisting of hard-core bosons. We generalize an identity due to Diaconis and Shahshahani which computes unitary matrix integrals over products of power sum polynomials. This allows us to derive two expressions for unitary matrix integrals over Schur polynomials, which can be directly applied to LRRW correlation functions. We then demonstrate a duality between distinct LRRW models, which we refer to as quasi-local particle-hole duality. We note a relation between the multiplication properties of power sum polynomials of degree n and fermionic particles hopping by n sites. This allows us to compute LRRW correlation functions in terms of auxiliary fermionic rather than hard-core bosonic systems. Inverting this reasoning leads to various results on long-range fermionic models as well. In principle, all results derived in this work can be implemented in experimental setups such as trapped ion systems, where LRRW models appear as an effective description. We further suggest specific correlation functions which may be applied to the benchmarking of such experimental setups.
Suitability of pressmud as an adsorption material in wastewater treatment and as a booster in soil fertility and productivity
Authors: Mohamad M , Osman N H , Rahim M K I A , Abustan I , A Zainol M R R M , Samuding K , Zakaria S N F , Abu F
Published: March 2023

Pressmud is one of the most abundant wastes produced by the sugarcane industry. However, it has received far too little attention as a reactive material for pollutant removal, although its beneficial effect on soil fertility and crop productivity is well established. This paper investigates the potential of pressmud to minimize heavy metal migration while boosting soil fertility and productivity. Firstly, the adsorbent was characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Field-Emission Scanning Electron Microscopy (FESEM) analyses, which showed the presence of functional groups such as carbonyl, hydroxyl, and silica capable of adsorbing metal ions. The cation exchange capacity (CEC) of pressmud is very high, ranging between 44.9 and 45.2 meq/100 g. Along with removal efficiency testing and evaluating breakthrough curves, characterization and adsorption analyses (batch equilibrium and column test) were carried out. The pressmud reveals promising adsorption characteristics, including a high organic content (17.62%) and the presence of carbon, which significantly affects its excellent removal effectiveness. Based on the removal efficiency test, pressmud successfully removes metal ions at the highest value, such as zinc (Zn), at 99.7%. Meanwhile, its breakthrough curve reveals that it efficiently retained all heavy metals, as these metals do not reach 1 to 10 pore volumes (p.v.), indicating that pressmud is a good material for heavy metal adsorption and soil productivity. This possible use establishes a new cyclical flow for the material and contributes to its minimization and reuse, adhering to circular economy ideas. However, pressmud must be disposed of properly to avoid adverse effects on humans and the environment.
Water quality index analysis in Kim-Kim River: Effects of Covid-19 movement control order
Authors: Mohiyaden H A , Sidek L M , Noh S M , Selamat M K , Marufuzzaman M
Published: March 2023

Movement Control Order (MCO) and Conditional Movement Control Order (CMCO) has been implemented throughout the country to reduce the effect of the COVID-19 outbreak. During MCO, several activities, including anthropogenic activities, are not allowed to be operated. Kim-Kim River, which receives most of the effluent from the industrial area, is chosen as a study area for investigating the impact of MCO toward its water quality trends. The results showed that the Water Quality Index (WQI) has improved from Class IV before MCO to Class III during MCO at the upstream of Kim Kim river. Overall, Kim-Kim river water quality has been developed by 19% during MCO. Although from the previous 10 years water quality trends confirm that Kim Kim River is categorised as a polluted river, with the continuation of MCO and the new norm of COVID19, the WQI are expected to be improved.
Changes in the spatial-temporal of the amount of sediment suspended in the Mekong Delta in Vietnam
Authors: Phuong D N L , Binh D V , Kantoush S A , Nguyen Q H , Vinh T L , Phuong M N T , Nguyen H T , Sumi T
Published: March 2023

Sediment depletion in the Vietnamese Mekong Delta (VMD) has brought threats to riverbed and riverbank dynamics. The main objective of this research is to make a relationship between turbidity and suspended sediment concentration (SSCs) and to assess temporal-spatial variations of SSCs in the VMD. In this regard, the SSCs were measured and monitored along the Tien and Hau Rivers under the Japan-ASEAN Science, Technology, and Innovation Platform (JASTIP) project and Mekong River Commission (MRC). Particularly, we installed three monitoring stations in main rivers and conducted two field surveys to collect data for assessing SSC values in the VMD. The results show that the SSCs in the delta are changeable seasonally with high values in the high-flow season and low values in the low-flow season. The Tien and Hau Rivers can be divided into two reaches. The upper reach has high SSC, decreasing seaward, whereas the lower reach has lower SSC, increasing seaward.
Analyzation of water demand projection for Johor River Basin
Authors: Yani F , Hussien N , Noor Z Z , Hafizan C
Published: March 2023

This paper presents the projecting or forecasting of water demand for the Johor River Basin (JRB) from the year 2020 up to 2050. The aim for this research is to quantify and analyse the demand for water in the future from each sector which is most crucial around JRB such as domestic/residential, industrial, agriculture, livestock and non-revenue water; it is a key element for water demand quantification for JRB. Recent work for this quantification is more generalizing in terms of water demand as a whole in Johor state. Meanwhile, this research are using composite approaches which involve secondary data from various local authorities and involved four different districts only around JRB. This research also covers the scope of water consumption baseline data and information of JRB with the recent report. It appears that quality of data in terms of availability and reliability is very important and must be dealt with carefully, with good judgement and good engagement with local stakeholders or authorities when it comes to decision making, therefore must be able to get a rapid and simple understanding of water demand for JRB. It is significant to this research which to accommodate with United Nations Development Program and also promote greater awareness of the Sustainable Development Goal (SDG-6) which to ensure availability and sustainable management of water and sanitation for all.
Based on physical model test and analysis of hydraulic erosion of warping dam
Authors: Zhong F Q , Huo A D , Zhao Z X
Published: March 2023

As a common engineering measure in “Gully consolidation and highland protection” project, warping dam plays a great role in soil and water conservation in the loess Plateau region. This paper selects the Yangjiagou small watershed in Qingyang City, Gansu Province as the research object, sets up a warping dam to simulate erosion reduction, and establishes a physical channel model with equal scale reduction, to reveal the reciprocal feeding mechanism of hydraulic erosion to the “Gully consolidation and highland protection” project. According to experimental calculations, the total erosion amount of the three erosion tests before the construction of the warping dam is 7.25kg, 8.02kg and 9.20kg, and the total erosion amount of the three erosion tests after the construction of the silt dam is 4.51kg, 5.25kg and 6.18kg. The sand interception efficiency in the three water flushing tests is 37.8%, 34.5% and 32.8%. The results show that the construction of warping dam can raise erosion base level and alleviate soil erosion effectively. And the warping dam can still play a part of its sediment reduction capacity after it has been scoured several times and partially destroyed. With the increase of use time, the effectiveness of the warping dam for blocking sand gradually decreases.
A performance study of R717 and R22 as the working fluid for OTEC plant
Authors: Chan W L , Chiong M S
Published: March 2023

The purpose of this paper is to compare the thermal efficiency of an ocean thermal energy conversion (OTEC) cycle using R717 and R22 working fluids. An OTEC system typically operates at the temperature difference between the average warm surface seawater of 30 °C and the cold deep seawater of 8 °C. The temperature difference will then power a turbine to produce electricity. R22 and R717 are two potential working fluids to be used in the OTEC cycle to absorb heat due to their saturation temperature. However, R22 is associated with higher global warming potential and the global warming potential (GWP) of 1,760, compared to R717 with zero GWP. The study shows that the thermal efficiency of R22 is 0.211% higher than R717. Moreover, the thermal power required by the water circuit to cool/heat the OTEC circuit for R717 is 13% higher than R22. However, the required working fluid flow rate of the R717 system is 81.5% lower than R22, making the former significantly smaller in size.