bluuebunny/crossref_metadata_2025 huggingface dataset:
Tight junction membrane proteins regulate the mechanical resistance of the apical junctional complex
Authors: Nguyen Thanh Phuong , Otani Tetsuhisa , Tsutsumi Motosuke , Kinoshita Noriyuki , Fujiwara Sachiko , Nemoto Tomomi , Fujimori Toshihiko , Furuse Mikio
Published: March 2024

Epithelia must be able to resist mechanical force to preserve tissue integrity. While intercellular junctions are known to be important for the mechanical resistance of epithelia, the roles of tight junctions (TJs) remain to be established. We previously demonstrated that epithelial cells devoid of the TJ membrane proteins claudins and JAM-A completely lack TJs and exhibit focal breakages of their apical junctions. Here, we demonstrate that apical junctions fracture when claudin/JAM-A–deficient cells undergo spontaneous cell stretching. The junction fracture was accompanied by actin disorganization, and actin polymerization was required for apical junction integrity in the claudin/JAM-A–deficient cells. Further deletion of CAR resulted in the disruption of ZO-1 molecule ordering at cell junctions, accompanied by severe defects in apical junction integrity. These results demonstrate that TJ membrane proteins regulate the mechanical resistance of the apical junctional complex in epithelial cells.
A TBK1 variant causes autophagolysosomal and motoneuron pathology without neuroinflammation in mice
Authors: Brenner David , Sieverding Kirsten , Srinidhi Jahnavi , Zellner Susanne , Secker Christopher , Yilmaz Rüstem , Dyckow Julia , Amr Shady , Ponomarenko Anna , Tunaboylu Esra , Douahem Yasmin , Schlag Joana S. , Rodríguez Martínez Lucía , Kislinger Georg , Niemann Cornelia , Nalbach Karsten , Ruf Wolfgang P. , Uhl Jonathan , Hollenbeck Johanna , Schirmer Lucas , Catanese Alberto , Lobsiger Christian S. , Danzer Karin M. , Yilmazer-Hanke Deniz , Münch Christian , Koch Philipp , Freischmidt Axel , Fetting Martina , Behrends Christian , Parlato Rosanna , Weishaupt Jochen H.
Published: March 2024

Heterozygous mutations in the TBK1 gene can cause amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). The majority of TBK1-ALS/FTD patients carry deleterious loss-of-expression mutations, and it is still unclear which TBK1 function leads to neurodegeneration. We investigated the impact of the pathogenic TBK1 missense variant p.E696K, which does not abolish protein expression, but leads to a selective loss of TBK1 binding to the autophagy adaptor protein and TBK1 substrate optineurin. Using organelle-specific proteomics, we found that in a knock-in mouse model and human iPSC–derived motor neurons, the p.E696K mutation causes presymptomatic onset of autophagolysosomal dysfunction in neurons precipitating the accumulation of damaged lysosomes. This is followed by a progressive, age-dependent motor neuron disease. Contrary to the phenotype of mice with full Tbk1 knock-out, RIPK/TNF-α–dependent hepatic, neuronal necroptosis, and overt autoinflammation were not detected. Our in vivo results indicate autophagolysosomal dysfunction as a trigger for neurodegeneration and a promising therapeutic target in TBK1-ALS/FTD.
Atomistic origins of compound semiconductor synthesis with computational neuromorphic engineering
Authors: Turfanda Aykut , Hakan Gürel Hikmet , Ünlü Hilmi
Published: March 2024

We propose the usage of multi-element bulk materials to mimic neural dynamics instead of atomically thin materials via the modeling of group II–IV compound semiconductor growth using vacancy defects and dopants by creating and annihilating one another like a complex artificial neural network, where each atom itself is the device in analogy to crossbar memory arrays, where each node is a device. We quantify the effects of atomistic variations in the electronic structure of an alloy semiconductor using a hybrid method composed of a semiempirical tight-binding method, density functional theory, Boltzmann transport theory, and a transfer-matrix method. We find that the artificial neural network resembles the neural transmission dynamics and, by proposing resistive switching in small areas with low energy consumption, we can increase the integration density similar to the human brain.
Excitation of exchange spin waves in a magnetic insulator thin film at cryogenic temperatures
Authors: Chen Jilei , Wang Hanchen , Wang Jinlong , Sheng Lutong , Liu Tao , Liu Song , Yu Dapeng , Yu Haiming
Published: March 2024

Spin waves and their quanta, magnons, are promising candidates for next-generation electronic devices, due to their low-power consumption and compatibility with radio-frequency-based electronic devices. For achieving magnon-based hybrid quantum systems for quantum memory and computation, the investigation of spin-wave propagation at cryogenic temperatures is highly required. In this article, we report the excitation and detection of exchange spin waves with wavelengths of tens of nanometers in an yttrium iron garnet (YIG) thin film at cryogenic temperatures. We find that the exchange spin waves are unidirectional in all temperature ranges, owing to the chiral dynamical dipolar coupling between the spin-wave mode in the YIG and the ferromagnetic resonance mode in the cobalt nanowire. Notably, a high exchange spin-wave group velocity of 2 km s−1 at 10 K is observed. Our results are promising for the development of high-speed and energy-efficient quantum magnonic devices operating at cryogenic temperatures.
A microscopic view of checkerboard and striped charge orders through doping antiferromagnetic Mott insulator
Authors: Wang Xuanlan , Zhu Wei
Published: March 2024

The emergence of charge order in doped Mott insulators has received considerable attention due to its relevance to a variety of realistic materials and experiments. To investigate the interplay between magnetic and charge order, we have studied the semiclassical Kondo lattice model, which includes both electronic and magnetic degrees of freedom. By combining Langevin dynamical simulations with the kernel polynomial method, our results reveal the presence of charged stripe order, checkerboard order, and non-uniform charge disorder in the near-half-filling regime. Importantly, our simulations show that both the doping level and the strength of the s-d exchange coupling play a crucial role in facilitating charge order formation. These phases give rise to distinct electronic structures as well as excitations in the magnetic dynamics, providing insights into the underlying mechanism of charge ordering phenomena.
Interpretable multi-domain meta-transfer learning for few-shot fault diagnosis of rolling bearing under variable working conditions
Authors: Che Changchang , Zhang Yuli , Wang Huawei , Xiong Minglan
Published: March 2024

To address the challenges of accurately diagnosing few-shot fault samples obtained from rolling bearings under variable operating conditions, as well as the issues of black box nature and delayed feedback to guide fault handling in intelligent diagnostic models, this paper proposes an interpretable multi-domain meta-transfer learning method. Firstly, vibration monitoring data of rolling bearings under different operating conditions are collected, and time–frequency domain features are extracted to construct multi-channel one-dimensional temporal samples as inputs. A multi-domain meta-transfer learning framework based on deep convolutional neural networks is then built to perform few-shot learning with multiple tasks under different operating conditions. The output results are reverse-reconstructed through a fusion hierarchical class activation mapping, and the feature maps are assigned different weights to obtain saliency maps corresponding to the inputs, thus improving the interpretability of the output results. Finally, the dataset of bearing vibration data under time-varying rotational speed conditions is used to validate the effectiveness of the proposed method. Experimental results show that the proposed method can achieve accurate fault diagnosis results under variable operating conditions with few-shot samples, and the diagnosis results can be fed back to the input for decision-making, enhancing the interpretability of the model. Compared with other models, it also demonstrates better robustness and accuracy.
Continua and persistence of periodic orbits in ensembles of oscillators
Authors: Ronge R , Zaks M A , Pereira T
Published: March 2024

Certain systems of coupled identical oscillators like the Kuramoto–Sakaguchi or the active rotator model possess the remarkable property of being Watanabe–Strogatz integrable. We prove that such systems, which couple via a global order parameter, feature a normally attracting invariant manifold that is foliated by periodic orbits. This allows us to study the asymptotic dynamics of general ensembles of identical oscillators by applying averaging theory. For the active rotator model, perturbations result in only finitely many persisting orbits, one of them giving rise to splay state dynamics. This sheds some light on the persistence and typical behavior of splay states previously observed.
Travelling modulating pulse solutions with small tails for a nonlinear wave equation in periodic media
Authors: Dohnal Tomáš , Pelinovsky Dmitry E , Schneider Guido
Published: March 2024

Travelling modulating pulse solutions consist of a small amplitude pulse-like envelope moving with a constant speed and modulating a harmonic carrier wave. Such solutions can be approximated by solitons of an effective nonlinear Schrödinger equation arising as the envelope equation. We are interested in a rigorous existence proof of such solutions for a nonlinear wave equation with spatially periodic coefficients. Such solutions are quasi-periodic in a reference frame co-moving with the envelope. We use spatial dynamics, invariant manifolds, and near-identity transformations to construct such solutions on large domains in time and space. Although the spectrum of the linearised equations in the spatial dynamics formulation contains infinitely many eigenvalues on the imaginary axis or in the worst case the complete imaginary axis, a small denominator problem is avoided when the solutions are localised on a finite spatial domain with small tails in far fields.
Dosimetric validation of SmART-RAD Monte Carlo modelling for x-ray cabinet radiobiology irradiators
Authors: Hill Mark A , Staut Nick , Thompson James M , Verhaegen Frank
Published: March 2024

Objective. Accuracy and reproducibility in the measurement of radiation dose and associated reporting are critically important for the validity of basic and preclinical radiobiological studies performed with kilovolt x-ray radiation cabinets. This is essential to enable results of radiobiological studies to be repeated, as well as enable valid comparisons between laboratories. In addition, the commonly used single point dose value hides the 3D dose heterogeneity across the irradiated sample. This is particularly true for preclinical rodent models, and is generally difficult to measure directly. Radiation transport simulations integrated in an easy to use application could help researchers improve quality of dosimetry and reporting. Approach. This paper describes the use and dosimetric validation of a newly-developed Monte Carlo (MC) tool, SmART-RAD, to simulate the x-ray field in a range of standard commercial x-ray cabinet irradiators used for preclinical irradiations. Comparisons are made between simulated and experimentally determined dose distributions for a range of configurations to assess the potential use of this tool in determining dose distributions through samples, based on more readily available air-kerma calibration point measurements. Main results. Simulations gave very good dosimetric agreement with measured depth dose distributions in phantoms containing both water and bone equivalent materials. Good spatial and dosimetric agreement between simulated and measured dose distributions was obtained when using beam-shaping shielding. Significance. The MC simulations provided by SmART-RAD provide a useful tool to go from a limited number of dosimetry measurements to detailed 3D dose distributions through a non-homogeneous irradiated sample. This is particularly important when trying to determine the dose distribution in more complex geometries. The use of such a tool can improve reproducibility and dosimetry reporting in preclinical radiobiological research.
Convolutional LSTM model for cine image prediction of abdominal motion
Authors: Weng J , Bhupathiraju S H V , Samant T , Dresner A , Wu J , Samant S S
Published: March 2024

Objective. In this study, we tackle the challenge of latency in magnetic resonance linear accelerator (MR-Linac) systems, which compromises target coverage accuracy in gated real-time radiotherapy. Our focus is on enhancing motion prediction precision in abdominal organs to address this issue. We developed a convolutional long short-term memory (convLSTM) model, utilizing 2D cine magnetic resonance (cine-MR) imaging for this purpose. Approach. Our model, featuring a sequence-to-one architecture with six input frames and one output frame, employs structural similarity index measure (SSIM) as loss function. Data was gathered from 17 cine-MRI datasets using the Philips Ingenia MR-sim system and an Elekta Unity MR-Linac equivalent sequence, focusing on regions of interest (ROIs) like the stomach, liver, pancreas, and kidney. The datasets varied in duration from 1 to 10 min. Main results. The study comprised three main phases: hyperparameter optimization, individual training, and transfer learning with or without fine-tuning. Hyperparameters were initially optimized to construct the most effective model. Then, the model was individually applied to each dataset to predict images four frames ahead (1.24–3.28 s). We evaluated the model’s performance using metrics such as SSIM, normalized mean square error, normalized correlation coefficient, and peak signal-to-noise ratio, specifically for ROIs with target motion. The average SSIM values achieved were 0.54, 0.64, 0.77, and 0.66 for the stomach, liver, kidney, and pancreas, respectively. In the transfer learning phase with fine-tuning, the model showed improved SSIM values of 0.69 for the liver and 0.78 for the kidney, compared to 0.64 and 0.37 without fine-tuning. Significance. The study’s significant contribution is demonstrating the convLSTM model’s ability to accurately predict motion for multiple abdominal organs using a Unity-equivalent MR sequence. This advancement is key in mitigating latency issues in MR-Linac radiotherapy, potentially improving the precision and effectiveness of real-time treatment for abdominal cancers.
Progress in superconducting REBa2Cu3O7 (RE = rare earth) coated conductors derived from fluorinated solutions
Authors: Obradors X , Puig T , Ricart S , Palau A , Coll M , Gutiérrez J , Farjas J , Bartolomé E
Published: March 2024

In this work, we review recent progress achieved in the use of chemical solution deposition (CSD) based on fluorinated metalorganic precursors to grow superconducting REBa2Cu3O7 (REBCO) films and coated conductors (CCs). We examine, first of all, the advances in optimizing the steps related to the solutions preparation, deposition and pyrolysis based on novel low-fluorine metalorganic solutions. We show that a new type of multifunctional colloidal solutions including preformed nanoparticles (NPs), can be used to introduce artificial pinning centers (APCs). We analyze how to disentangle the complex physico-chemical transformations occurring during the pyrolysis with the purpose of maximizing the film thicknesses. Understanding the nucleation and growth mechanisms is shown to be critical to achieve a fine tuning of the final microstructure, either using the spontaneous segregation or the colloidal solution approaches, and make industrially scalable this process. Advanced nanostructural studies have deeply modified our understanding of the defect structure and its genealogy. It is remarkable the key role played by the high concentration of randomly distributed and oriented BaMO3 (M = Zr, Hf) NPs which enhance the concentration of APCs, such as stacking faults and the associated partial dislocations. Correlating the defect structure with the critical current density Jc
(H,T,θ) allows to reach a tight control of the vortex pinning properties and to devise a general scheme of the vortex pinning landscape in the whole H–T phase diagram. We also refer to the outstanding recent achievements in enhancing the vortex pinning strength by shifting the carrier concentration in REBCO films towards the overdoped state, where the pinning energy is maximum and so, record values of critical current densities are achieved. This confirms the performance competitiveness of nanocomposite CCs prepared through the CSD route. We conclude with a short summary of the progress in scaling the CC manufacturing using fluorinated solutions.
Performance investigation of MAPbI3/MASnI3 based all-perovskite tandem solar cell using SCAPS simulation
Authors: Ahmed Sumon , Rahman Naimur , Dulal Haque Md , Hasan Ali Md , Zafor Md Touhidul Islam Abu
Published: March 2024

Due to the complexity of the fabrication process of tandem solar cells, perovskite materials provide a cost-effective and simpler fabrication solution. In this work, MAPbI3/MASnI3 Perovskite-based Tandem solar cell has been explored numerically by using SCAPS-1D. Methylammonium Lead Iodide (CH3NH3PbI3 or MAPbI3) and Methylammonium Tin Iodide (CH3NH3SnI3 or MASnI3) have been considered as wide bandgap (WBG) and narrow bandgap (NBG) absorber material for the top cell and bottom cell, respectively. WBG top cell and NBG bottom cell are both investigated through the change in the depth of perovskite materials at the current matching conditions at the illumination of Standard AM 1.5 spectrum. The all-perovskite MAPbI3/MASnI3 tandem solar cell with copper (I) oxide (Cu2O) hole transport layer has achieved excellent performance with a maximum power conversion efficiency (PCE) of 32.74% with V

oc
of 1.68 V, J

sc
of 24.6 mA cm−2, and fill factor (FF) of 79.39%, respectively.
Effect of metal (Cr, Sr, Ag, Cu) doping on the performance of lead-free RbSnI3 based perovskite solar cells: A theoretical approach
Authors: Sarkar Joy , Chaki Tanmay , Mandal Pradip Kumar , Chatterjee Suman
Published: March 2024

Perovskite solar cells based on lead have witnessed unprecedented growth over the past decade, achieving an impressive power conversion efficiency (PCE) of 26.1%. However, lead toxicity remains a concern for commercialization. In order to resolve the matter, scientists have been investigating alternative materials; in this context, rubidium-based lead-free perovskites like RbSnI3 may be a promising alternative because it has a high optical conductivity and absorption coefficient. Density Functional Theory (DFT)-based first-principles studies are used in this work to examine the effect of metal doping (specifically Cr, Sr, Ag, and Cu) on the optoelectronic and structural characteristics of orthorhombic RbSnI3 perovskite. In addition, we conducted a comprehensive study to investigate the impact of metal doping on the formation energy, structural stability, and HOMO–LUMO energy levels of RbSnI3 perovskite. Introducing transition metal cations (Cr2+, Ag+, and Cu+) at the Rb site results in a flat band in the conduction band region, transforming the RbSnI3’s indirect band gap into a direct one and significantly affecting the optoelectronic properties. The DFT results are then integrated into the Solar Cell Capacitance Simulator (SCAPS-1D) to estimate the effectiveness of the modeled device. The Cu-doped RbSnI3 device exhibits the highest PCE of 20.2%. Furthermore, Ag and Cu doping in RbSnI3 increases bond length, which reduces exciton binding energy and helps with charge carrier generation.
Parametric factorization of non linear second order differential equations
Authors: González Contreras Gabriel
Published: March 2024

In this paper the factorization method introduced by Rosu & Cornejo-Pérez for second order non linear differential equations is generalized by adding a parameter in order to obtain the general solutions for the mixed quadratic and linear Liénard type equation. The new parametric factorization is used to obtain complete analytic solutions for nonlinear second order differential equations. The parametric factorization introduced in this article reduces to the standard factorization scheme when the parameter goes to zero. As an example, we apply the parametric factorization approach to solve the generalized Fisher equation and the Israel-Stewart cosmological model. The parametric factorization presented in this paper can be used in other non linear mixed Liénard type equations.
Split Air-conditioner Noise Source Identification through Sound Intensity Mapping
Authors: Zikri J.M. , Norhakim M.S.M. , Sani M.S.M.
Published: March 2024

As the global warming takes place in years, the electrical appliances such as air-conditioner have been installed in most residential, industrial, or even in the education institution to provide better air quality and ultimately reduces the heat transfer in the ambient. Common use of split air-conditioner system to give maximum capacity in a space is responsible to the accumulated noise generated by the outdoor unit of the system. Therefore, an experimental study has been done to identify the noise rating and location of the highest noise level emitted by the system through different temperature and fan speed. The sound intensity mapping together with the sound power level will be applied to ensure the reliability of the data for the study purposes. Generally, the results indicated that the noise were concentrated at the compressor and fan blades whereas the level were observed to be higher with the lower temperature and higher fan speed operated. The highest noise level also reported as high as 99.08 dB(A) which located at the compressor. Hence it can be concluded that mitigation action is needed since considerable noise are generated by the application of air-conditioner particularly at the compressor and condenser fan.
Exploratory Structural Modification and Nonlinear Based Analysis of Tuned Mass Dampers
Authors: Rousou K. , Abdul Rani M.N. , Bahari A.R. , Kyprianou A.
Published: March 2024

This article presents a structural modification-based analysis of tuned mass dampers that motivates to investigate the performance of a cubic stiffness absorber. The rationale behind this investigation is that the analysis of vibration absorber using structural modifications could pave the way for the use of nonlinear mechanical elements in vibration absorption applications. To achieve this, the article reviews the fundamentals of structural modification-based analysis of absorbers. It then examines the effects of using the Duffing oscillator as an absorber. The Duffing oscillator is integrated into the primary system using the describing function and the amplitude-dependent nonlinear frequency response functions are computed. The results of this analysis are compared with those of a linear absorber in order to clarify the differences and point out possible directions for further development.
Integrated algorithm evaluation of a scalable digital power management innovation model
Authors: Lv Zhining , Li Yi , Zhao Jie , Lai Tiande , Ou Yuhang , Fan Xiaolong
Published: March 2024

Maintaining contemporary society’s steady progress depends on the reliable functioning of the electrical grid. The complexity and nonlinearity of today’s power networks make it difficult to manage them using conventional mathematical modeling approaches. To get around these problems, researchers have started using machine learning methods, such transient stability evaluation that is based on machine learning. This research suggests a way to evaluate the transient stability of power systems by making use of the complex feature extraction capabilities of multi-layer perceptron (MLP) networks. Another approach is to suggest an ensemble learning model that uses the easy-ensemble undersampling technique to deal with power system transient stability data that is unbalanced. This method preserves unstable power system samples, performs multiple undersampling on stable samples and combines unstable and undersampling samples into multiple new balanced training sets for MLP model training. The final ensemble model is obtained through voting integration strategy. Through conducting a comparative evaluation of individual models and ensemble models, this paper discovers that the ensemble learning models exhibit superior sensitivity and accuracy in effectively addressing system instability.
Structural Stability and Weak Points Mechanism of a High and Vertical Enclosed Isolated Phase Bus
Authors: Fu Jianwen , Yang Bo , Wang Shuaishuai , Wang Xiaomei , Qian Feng , Feng Antao , Cai Feihong , Zhang Hailong
Published: March 2024

Recently, with the rapid rise of new energy generation, pumped storage power stations also have experienced rapid development. Due to the considerable vertical height of these power stations, high and vertical enclosed isolated phase buses (EIPB) are more and more widely used. This type of high and vertical EIPB structure differs from the horizontal EIPB structure, as it is more significantly influenced by the gravitational load during actual operation. Thus, it is crucial to investigate the stability of the novel high and vertical EIPB structure under its own gravity load. In this study, the strength of the I-beam and cross-arm of the EIPB under the influence of the gravitational load was studied through analytical calculations and finite element static analysis. The results indicate that the strength of the I-beam and cross-arm is within the threshold of the corresponding material’s load-bearing capacity, demonstrating the stability of the EIPB structure. This work holds significant value for the structural design and further optimization of high and vertical EIPB.
Design and Simulation of Autonomous Up-and-down System for Transmission Line Live Operation Robot with the UAV Assistance
Authors: Zou Dehua , Jiang Zhipeng , Liu Lanlan , Dai Chenhao , Jiang Wei
Published: March 2024

Aiming at the current bottleneck problem that restricts the practical application of robot system engineering in transmission line live operation, in order to improve the on-line and off-loading efficiency of live working robots on transmission lines and improve the practical level of the robot system as a whole, this paper proposes a design and operation method of autonomous on-line and off-loading mechanism of double-arm live working robots based on UAV assistance. Firstly, the realization process of autonomous up-and-down of the robot was analyzed, based on which the structure of the auxiliary hook of the up-and-down system and the lifting winch were designed. Then, the force analysis was carried out on the up-and-down process of the robot, and the appropriate winch drive motor was selected through theoretical calculation. In order to ensure the rationality of the up-and-down process, the operation motion planning was carried out on the up-and-down of the robot. Stress analysis and simulation were carried out on the maximum load bearing point of the auxiliary hook and the walking wheel mechanical arm under different states, and the results showed that the hook and the robot arm could meet the requirements of the robot loading and unloading, and the whole robot loading and unloading system was designed reasonably. Compared with the traditional loading and unloading system designed in this paper, the loading and unloading efficiency could be improved. It has important theoretical significance for the development of the physical system of robot uplink and down.
Research on Condition Assessment Method of Transformer Based on Cloud Model
Authors: Zhang Shize , Peng Chao , Xiong Yi , Jin Yating , Mao Jiawei
Published: March 2024

The traditional evaluation method of transformer has the problems of strong subjectivity of threshold value and fuzzy correlation of state quantity, which is difficult to accurately evaluate the operation quality of transformer. In order to solve these problems, this paper proposes a comprehensive evaluation method of transformer performance evaluation and operation quality based on cloud model. The evaluation index system of power transformer operation quality considering performance is constructed, including target layer, performance layer and index layer. The triangular fuzzy number is used to optimize the set of expert opinions, and the indexes are combined and weighted by fuzzy analytic hierarchy process and entropy weight method. After the data is degraded, the membership matrix of transformer operation index is constructed by using the cloud model, and the performance state weighting and membership degree are comprehensively considered to realize the performance evaluation of transformer and the comprehensive evaluation of operation quality based on performance. By using this method to predict 10 transformers in operation for a period of one month, it is possible to accurately identify abnormal situations on site, with a prediction accuracy of 96.28%. Compared with the traditional method of “predicting first and then diagnosing”, it has improved by 14.32%, overcoming the shortcomings of subjectivity, ambiguity, and ignoring the correlation of state variables in traditional evaluation methods. This method provides new ideas and methods for accurate evaluation of transformers.
Analysis and Preventive Measures for an Abnormity of 220kV Isolating Switch
Authors: Yang Sen , Zhang Dawei , Ju Xinxin , Duan Liankai , Hao Qiang , Wang Shuai , Su Hainan
Published: March 2024

With the development of the power grid, the cutter brake is a kind of main equipment used cooperatively in the transmission and distribution line of the substations with the circuit breaker in the operation and maintenance of the electric power system. Its main role is to ensure the safety of the staff during the maintenance of high voltage equipment. The cutter brake forms a clear disconnection point to provide the staff with a sufficiently large insulation interval between the equipment in need of repair and other energized parts. In the long-term operation, various reasons may lead to various failures of the cutter brake, causing great security risks to the safe and stable operation of the power grid and personal safety. This paper is mainly focused on analyzing the abnormal phenomenon of the poor contact of the dynamic and static contact fingers of B phase of I cutter brake of Xinlang Line 1 in the 220kV substation, which causes most of the current to flow through the B phase of Xinlang Line 2. Future management and preventive measures for this type of cutter brake are also proposed in this paper.
Study on Transmission Attenuation Characteristics of Abnormal Discharge Current in Transmission Lines
Authors: Zhao Hailong , Pang Songling , Zhang Ruien , Huo Meiyi , Liu Yu
Published: March 2024

In order to analyze the transmission characteristics of abnormal discharge current in transmission lines, considering the frequency-dependent characteristics of line parameters, the transmission of abnormal discharge micro-current is studied theoretically and analyzed with examples. Then, ATP-EMTP is used to establish a hidden danger micro-current transmission model for the elevated line, and the micro-current transmission situation is simulated. The influence of frequency and different voltage levels on the hidden danger micro-current transmission characteristics is mainly considered. The results show that the higher the frequency of the initial signal, the larger the equivalent resistance and the smaller the equivalent inductance of the line. The frequency has little effect on capacitance and conductance. The attenuation constant of high-voltage class lines with multiple split wires is greater than that of low voltage class lines with single split wires, and the attenuation constant only increases slightly with the increase of split wires.
An Improved Design for a Heat Sink of a Power Conversion System Adapted to the High Altitude and Cold Environment of the Plateau
Authors: You Xiaolong , Luo Chengdong , Pu Zewei , Hu Jincheng , Zhou Lidan , Yao Gang
Published: March 2024

Currently, there are many studies on power conversion system (PCS) in the industry, but there are few studies on high-altitude and plateau application scenarios. This paper takes the extreme environment of plateau and high altitude as the research background, uses PLECS software to establish a thermoelectric simulation of a three-phase LCL grid-connected inverter, and calculates the total heat loss of the power devices IGBT and diodes in the PCS and the power loss of the grid-connected filter. Combining the overall heat generation of IGBTs, diodes and filters and considering the characteristics of high-altitude extreme environments, two liquid-cooled radiators with different structures were designed to measure the thermal resistance and pressure loss of the two radiators (reflecting Flow resistance) and heat dissipation efficiency are quantitatively calculated. The results show that the heat dissipation performance of the liquid cooling radiator designed by the latter is better than that of the former, verifying that by improving the channel structure and size of the liquid cooling radiator, the thermal resistance and flow resistance of the radiator itself can be reduced, and its heat dissipation performance can be improved.
Probabilistic Voltage Optimization Considering Load Static Voltage Characteristics
Authors: Deng Hongyuan , Jia Yudong , Zhu Yongqiang , Xia Ruihua
Published: March 2024

In the conventional power flow calculation, the load is mostly treated as a constant power node. When the voltage deviation occurs, the static voltage characteristics of the load will change, resulting in the change of the power flow calculation. This situation is more likely to occur in the distribution network with distributed power supply. Therefore, it is very important to consider the static voltage response characteristics of the load in the power flow calculation. In the existing literature, when evaluating and optimizing voltage stability, deterministic indicators are usually used to evaluate the voltage level of the system. In the active distribution network with uncertain new energy output, this method has its limitations. Based on the above analysis, this paper uses the power flow calculation method considering the static voltage characteristics of the load to solve the node voltage distribution of the distribution network system. Considering the uncertainty of new energy output and load, the semi-invariant method is used to analyze the probabilistic power flow. An evaluation index considering the digital characteristics of voltage deviation distribution is proposed. The voltage optimization model is established according to the proposed index, and the genetic algorithm is used to solve the problem. The IEEE33 node standard example is simulated to verify the correctness and feasibility of the proposed method.
Study on the Physical Properties of Hydrogen-Doped Natural Gas Based on Equation of State
Authors: Ouyang Xin , Qin Chuan , Peng Shiyao , He Yuming , Wang Weijia
Published: March 2024

As a zero-emission green clean energy, hydrogen energy is an important means to achieve the strategic goal of carbon neutrality and an important part of the energy Internet. Hydrogen-doped natural gas transportation is an economical and feasible scheme to realize long-distance transportation of hydrogen by using the existing natural gas pipeline network. However, the addition of hydrogen to natural gas will cause obvious changes in the physical properties of the transport medium, which will have a certain impact on the transport characteristics and flow measurement of the pipeline. The main problem is that we need to understand the changes of physical properties after natural gas mixed with hydrogen to ensure the safe operation of natural gas pipe network mixed with hydrogen. Based on this situation, this paper takes BWRS equation as the theoretical basis, selects typical natural gas temperament, calculates and solves the physical parameters of natural gas under different hydrogen blending ratios, and compares them with the standard physical reference values. After verification, the results are used to explore the physical properties of hydrogen-doped natural gas with hydrogen blending ratio, temperature and pressure as variables. The relative average absolute value error (RAAD) of the calculated physical properties of hydrogen-doped natural gas in this paper is less than 2% compared with the reference value of standard physical properties, which can provide theoretical data basis for studying hydrogen-doped pipeline transportation, ensuring pipeline transportation safety and hydrogen-doped natural gas metering.
Research on the Technology of Full Cylinder Concrete Bite Pile of Deep Riprap Cofferdam
Authors: Huang Wenhui , Zhang Jiawei , Wu Yuheng
Published: March 2024

In order to solve the construction problem of deep ripped-rock cofferdam occluding pile under complex geological conditions, this paper studies the occluding pile engineering of Shenzhen-Zhongshan Link Construction pipe prefabrication yard as carrier. The research contents of this paper include the formation of occlusal pile, the reasonable combination of construction equipment, the optimization of concrete mix ratio, the treatment of isolated rock and the demolition of occlusal pile, etc., forming the key technology of the construction of cofferdam concrete occlusal pile under complex geological conditions at sea. Through the construction practice, the application of this technology has obtained a good effect of water sealing, and can provide reference for subsequent similar projects.
Study on the Optimized Matching of VNT and EGR Systems in a Diesel Engine
Authors: Xue Zhentao , Lv Huimin , Liu Yang , Tian Ruixiao , Tang Dong
Published: March 2024

An experimental investigation of the coupling relationship between the VNT (Variable Nozzle Turbine) and EGR (Exhaust Gas Recirculation) systems was carried out in this study on a four-valve common-rail diesel engine in bench tests, as well as a transient optimization of the VNT and EGR control strategies. It was found that the overall level of NOX and flue gas emissions decreased with decreasing VNT opening. When the opening of the EGR valve was in the range of 5%-10%, the NOX and soot emissions could be reduced simultaneously by decreasing the VNT opening; the response of the intake volume was greatly improved by modifying the coordinated control strategy by boosting the control strategy under the acute load step condition; the NOX emission was significantly reduced by 6% overall, and the soot was reduced by 22.8% and the CO2 emission was improved in the transient-optimized WLTC test cycle. Therefore, by coupling the VNT and EGR systems and optimizing them transiently, emissions of pollutants during rapid engine acceleration can be decreased.
The Application and Research of Particle Swarm Optimization Radial Basis Function Network Driven by Edge Computing in Bogie Fault Diagnosis
Authors: Gao Mingliang , Fu Changzhao , Wu Jianguo , Yu Tang , Lu Rongqin , Xi Xin , Wang Yang , Sun Yi
Published: March 2024

The bogie system is a key system that affects the safety and quality of high-speed train operation. Constructing a fault diagnosis model for the bogie system can effectively improve the safety and comfort of high-speed train operation. The traditional modeling method uses the BP neural network to fit the temperature and other parameters of the bogie system. However, because the BP neural network is prone to fall into local minima, slow convergence and poor diagnostic accuracy, this paper proposes a radial basis function network bogie fault diagnosis model based on particle swarm optimization based on edge computing. The model combines edge computing and particle swarm optimization algorithm to improve the accuracy and real-time of bogie fault diagnosis. By implementing model training and inference on edge devices, data transmission latency has been reduced and diagnostic efficiency has been improved. A particle radial basis neural network (PSRB) was designed using a highly convergent particle swarm optimization algorithm, and the parameters of the radial basis neural network (RBF Neural Networks) were optimized using the Particle Swarm Optimization algorithm. Based on the complexity of the input parameters of the bogie system, determine the input and output parameters of the model, and use particle swarm optimization algorithm to search for the optimal values of the basis function center, width, and output layer weight threshold of the RBF neural network. The composite algorithm was applied to the fault diagnosis of the bogie system, and a particle radial basis neural network bogie fault diagnosis model was designed. The simulation and experimental results of the model show that the diagnostic model can effectively improve the identification accuracy of fault diagnosis, with a minimum error accuracy of 0.0255, saving computation time. The computation time is reduced to 2.9 seconds, eliminating the influence of non target parameters on the inversion results. This model can also be used in other systems of high-speed trains and has practical application value.
Potential Environmental Impacts Caused by Sedimentation at the Tambakboyo Retention Basin D.I.Yogyakarta to Fulfill the Needs For Watershed
Authors: Nuranto S , Putri I N , Ustriyati S N , Jayatri F N M , Sembada P T S
Published: March 2024

The use of the Tambakboyo Retention Basin for more than 10 years has led to sedimentation at the bottom of the reservoir due to precipitated particles that are transported along with the water flow. Sedimentation of this reservoir can have several impacts on the environment. This study aims to analyze the possible environmental impacts that could occur in the Tambakboyo Retention Basin through the results of an analysis of the sedimentation rate and volume of water availability that has been carried out in previous studies. The results of previous studies indicate that the sedimentation rate in the Tambakboyo Retention Basin is included in category I or very light. However, several impacts may occur if there is no management, including reduced reservoir water holding capacity, flood hazard, excessive soil enrichment, lack of water so that the reservoir is no longer useful, and can even damage the reservoir. Thus, sediment management efforts need to be carried out, including repairing open land (greening), dredging sediments in the reservoir, and building sediment traps upstream of the reservoir.
The numerical investigation of turbulence and scour interaction around the permeable groynes at the channel bend
Authors: Sisinggih D , Wahyuni S , Rasyid Adenan , Maruf M. F. , Halik G
Published: March 2024

Turbulence, particularly Reynolds Stress, plays a significant role in the flow field surrounding groynes, causing local scour. A limited number of studies have comprehensively analyzed the flow and turbulence structures encompassing a series of groynes in channel bends. This study numerically investigated the interplay between turbulence, sediment deposition, and scouring in a sharp channel bend with permeable groynes. The results show that the inner bank maintained high velocity, while permeable groynes decreased longitudinal velocity near the outer bank. Implementing permeable groynes structures reduced bottom velocity and increased flow separation. Turbulent kinetic energy distribution across the bend, particularly streamwise, influenced scour development more than vertical motion.
Attempts to reduce cavitation phenomena at the Ciawi Dam inlet conduit using CFD Modeling
Authors: Sujono H , Haribowo R , Purwanto T S
Published: March 2024

The conduit bottom outlet is prone to cavitation damage on its channel surface, and one preventive measure is the installation of air ventilation. This research aims to grasp flow characteristics comprehensively, predict cavitation likelihood at the intake, and assess the impact of a ventilation pipe’s installation. Utilizing Computational Fluid Dynamics (CFD), the study modeled flow dynamics, focusing on velocity and pressure variables. The Ciawi bottom outlet intake was meticulously modeled at a 1:1 scale under normal water level conditions, and model accuracy was validated through physical testing by BHGK. The research includes two series: Series 0 (intake without ventilation pipe) and Series 1 (intake with ventilation pipe), with gate opening heights varied at 25%, 50%, 75%, and 100% for both series. Simulation results show that in Series 0, potential cavitation damage is indicated at a 75% gate opening in sections 3 and 4 with a cavitation index of 0.11. Series 1, featuring ventilation pipe installation, demonstrated positive outcomes, eliminating potential cavitation damage in the inlet bottom outlet, with all cavitation indices surpassing 0.2. This study provides crucial insights for preventing cavitation damage in conduit bottom outlets through the strategic deployment of ventilation systems.
Land suitability studies for paddy cultivation in Dadahup Swampy Irrigation Area
Authors: Handoko D , Istiarto  , Karlina
Published: March 2024

The Dadahup Swampy Irrigation Area is crucial in the government’s Food Estate initiative to enhance food security in Indonesia. Following extensive infrastructure improvements, including network rehabilitation and gate construction between 2020 and 2022, a pilot project was initiated in block A5. However, rice yields in this area still need to improve, primarily due to inadequate land management practices. This study evaluates and maps land suitability for paddy cultivation in the Dadahup Swamp Irrigation Area, employing a combination of laboratory data and field research integrated with geographic information system (GIS) technology. Various parameters were considered, such as climate factors (temperature and water availability), soil characteristics (drainage, texture, depth), peatland attributes (thickness, maturity), nutrient content (CEC, base saturation, pH, C-organic), available nutrients (nitrogen, phosphorus, potassium), salinity, alkalinity, pyrite depth, and inundation levels during planting. Then, thematic raster mapping was conducted using the Inverse Distance Weighted (IDW) method, followed by reclassification based on Food and Agriculture Organization (FAO) standards for land evaluation. The result categorized Block A5 into three suitability classes: S1 (highly suitable), S2 (moderately suitable), and S3 (marginally suitable). Approximately 22.5% of Block A5 is highly suitable (S1), 39.5% is moderately suitable (S2), and around 38% is marginally suitable (S3).
Correlational of soil permeability and infiltration rate at the ITERA infiltration drainage development plan
Authors: Kiranaratri AH , Bisri M , Asmaranto R
Published: March 2024

Physical development has an impact on the availability of groundwater. The limited water surface requires humans to manage available wisely. Institut Teknologi Sumatera (ITERA) is a state campus on the Island of Sumatera and has an area of 275ha. The eco-drain concept attempted to recover groundwater at all masterplan development. This study aims to reveal how much influence infiltration rate has on soil permeability in the ITERA Infiltration Drainage Development Plan. This research used quantitative research using a correlational approach by processing primary data and further analyzing it in the soil mechanics laboratory at the 8 points of the equal research location. Infiltration rate data was obtained using a double-ring infiltrometer and analyzed with the Horton Method, then the sampling at a depth of ±50 cm analysis with the Falling Head Method. Based on the result, there is no correlation between both tests and resulted in different soil types. The infiltration rate test result of the soil type is loamy sand – sandy loam with moderately – moderately slow infiltration classification. The soil permeability type is fine sand or silty clay with medium and low permeability, and the infiltration rate only affected 37.6% of the permeability soil result.