Space charge behavior is important in the oil-immersed-paper insulation converter transformers for HVDC transmission. This paper reports an investigation of space property samples with two layers and oil. Based on pulsed electroacoustic (PEA) technique, a waveform recovery method was proposed to get rid effects interface anisotropy PEA result, distributions two-layer under different voltage oil thicknesses were measured. It's found that charges same polarity as side electrode accumulated at...

We report fabrication of flexible all-solid-state transparent electrochromic patterned microsupercapacitors based on two-dimensional layered nanostructured molybdenum oxide (MoO3–x)/poly(3,4-ethylenedioxythiophene)–polystyrenesulfonate (PEDOT:PSS) nanocomposite electrodes. Exceptional electrochemical performance the includes fast kinetics and response times, high specific capacitances (up to 79.2 C/g, 99 F/g, 2.99 mF/cm2), Coulombic efficiencies 99.7% over 2500 cycles. Such exceptional is...

As the temperature gradient always exists in insulation of power equipment, influence on oil-impregnated paper is studied by experiments and simulation. It's found that both single-layer double-layer structures, heterocharges appear near lower electrode, increase with enhancement field stress, resulting more considerable distortion. However, there are samples while distortion severe samples. Numerical simulations were carried out to investigate mechanism effect. It indicated space charge...

Abstract In longwall top coal caving (LTCC) mining methods, problems such as large deformations, loss of resources, and excavation relay out balance are often encountered with the increased production in single panels. To address these problems, a novel non‐pillar technology LTCC was used based on equilibrium theory. This approach could cut off stress transmission, eliminate pillar, retain gob‐side entry. this technology, entry is first excavated along roof coal, then four techniques applied...

Abutment pressure distribution is different when a longwall panel passing through the abandoned gate roads in damaged coal seam. According to geological condition of E13103 Cuijiazhai Coal Mine China, theoretical analysis and finite element numerical simulation were used determine front characteristics face 70, 50, 30, 20, 10, 5 m from roadways. The research results show that influence range abutment 40 45 outby face, peak value related distance between When roadways reduced 50 10 m, kept...

Heterogeneous graph pre-training (HGP) has demonstrated remarkable performance across various domains. However, the issue of heterophily in real-world heterogeneous graphs (HGs) been largely overlooked. To bridge this research gap, we proposed a novel contrastive learning framework, termed HGMS, which leverages connection strength and multi-view self-expression to learn homophilous node representations. Specifically, design edge dropping augmentation strategy that enhances homophily...

By combining electrochemical experiments with mass spectrometric analysis, it is found that using short chain oligomers to improve the cycling stability of conducting polymers in supercapacitors still problematic. Cycling tests via cyclic voltammetry over a potential window 0 1.0 V or 1.2 two-electrode device configuration resulted solid-state electropolymerization and scission. Electropolymerization aniline tetramer generate long shown be possible despite suggested decrease reactivity...

Shaped charge blasting (SCB)—a directional fracture technology—has the disadvantages of low safety, harmful gas, and dust emissions. This study proposes a new type rock-breaking technology called shaped hydraulic (SCHB) that uses water as medium instead air. To verify effectiveness method, we performed theoretical analysis. Twelve groups on-site roof-cutting tests were carried out on SCB SCHB for comparison in coal mine. The results showed that, although both methods achieved goal roof...

Indoor fires pose significant threats in terms of casualties and economic losses globally. Thus, it is vital to accurately detect indoor at an early stage. To improve the accuracy fire detection for resource-constrained embedded platform, method based on multi-sensor fusion a lightweight convolutional neural network (CNN) proposed. Firstly, Savitzky-Golay (SG) filter used clean three types heterogeneous sensor data, then cleaned data are transformed by means Gramian Angular Field (GAF) into...

Under the conditions of high ground stress and mining disturbance, strata breakage that is induced by severe. Thus, it critical to investigate structural characteristics key (KS) in deep thick mining. This study introduces an innovative technology, namely, directional blasting fracturing, which energy-gathering tube installed a borehole explosive detonated break roof specified direction. A theory balanced bulk filling established based on requirements developing voussoir beam structure, can...

This article presents an integrated approach for theoretical analysis and numerical modeling to investigate the mechanism of roof presplitting its reasonable parameters in hard longwall top-coal caving face. The test site is located city Jinzhong, Shanxi Province, China. results indicated that when angle remains constant, tensile stress at unpenetrated surface approximately exponentially distributed with height. When height variation curve parabolic. As increases, required face exceed...

The mechanical properties, morphology, crystallization, and melting behaviors nonisothermal crystallization kinetics of poly (trimethylene terephthalate)(PTT)/maleinized acrylonitrile-butadiene-styrene (ABS-g-MAH) blends were investigated by an impact tester, polarized optical microscopy, differential scanning calorimetry (DSC). results suggested that the ABS-g-MAH component served as both a nucleating agent for increasing rate toughening improving strength PTT. When content was 5wt.%, blend...

As the temperature difference exists between inner and outer conductors of high voltage DC cables in practice, it is important to study space charge behavior under gradient. However, due effect on acoustic propagation, necessary waveform recovery method pulsed electroacoustic (PEA) measurement. In our previous study, only effects velocity attenuation were considered recovery. density material will not be continuously uniform a gradient, dispersion waves change resistance should also taken...

Noncoal pillar mining with automatic formation of a roadway is new coal method that tailored to improve the resource recovery rate and reduce investment in tunneling. Using this proposed method, reuse entry formed by roof cutting instead In paper, S1201-II working face Ningtiaota Coal Mine was used as case study. The stress distribution surrounding rock deformation characteristics reused during process second were studied through FLAC 3D numerical simulations combined field measurements....

Three-dimensional (3D) mechanical microenvironment, such as 3D strain field in tissue engineering scaffolds have crucial impact on the interactions between scaffold architecture, stimuli, and differentiation. However discontinuity induced by pores brings challenge to measurement of strains scaffolds. Herein, we present a optical coherence elastography (TES-OCE) method visulize full-field fields when cells are cultured explore relaship stimulation cell A semi-continuous digital volume...