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This study analyzes the optimization of Extra High Voltage (EHV) transmission line design parameters by Uttar Pradesh Power Corporation Limited (UPPCL) in India to improve power grid efficiency and reliability. UPPCL reduced insulation specifications for 400 kV lines from 27 to 21 disc insulators and decreased live metal clearance from 2600 to 2400 mm, resulting in 7–9% cost savings per line and reduced right-of-way requirements. While initial test lines performed satisfactorily for over 5 years, longer lines experienced operational challenges related to insulator quality, bird activity, and design margins. Tripping issues emerged during adverse weather conditions, particularly in foggy winter periods. Root cause analysis revealed the need for stringent insulator quality control, regular cleaning to mitigate bird dropping contamination, and potential corona ring design improvements. This case study demonstrates how targeted EHV transmission line optimization can yield significant cost and environmental benefits, while highlighting the importance of balancing economic gains with reliability and safety considerations. The findings provide valuable insights for future EHV transmission line designs and upgrades across India's power grid. [ABSTRACT FROM AUTHOR]

The negative influence of single-phase-to-ground faults in networks with an isolated neutral, resulting from a breakdown of pin insulation, is analyzed. A concept for early detection of damage to pin insulators is proposed, based on measuring changes in leakage current through the insulators caused by changes in the capacitance of the “pininsulator-wire” system. For this purpose, a simulation of the system was done. A model of the geometric dimensions of the insulator is created with taking into account the design features of the installation of the line wire in the AutoCAD software package and the distribution of the electric field is simulated in the Comsol Multiphysics 5.6 package, which makes it possible to estimate the electrical capacitance. The dependence of the calculated electrical capacitance of ShF-20G insulators on the dielectric constant, diameters and grades of wires used on 6-10 kV overhead power lines and options for wire bundles is considered. Numerical values of the capacitance of the “pin-insulator-wire” system were obtained for different configuration options. It has been shown that the state of the insulator material has a decisive influence on the capacity of the system. References 11, figures 2, tables 2. [ABSTRACT FROM AUTHOR]

With the implementation of intelligent unmanned aerial vehicles (UAVs) in power equipment inspection, managing the obtained inspection results through information technology is increasingly crucial. This paper collected insulator images, including images of standard and self-exploding insulators, during the inspection process using intelligent UAVs. Then, an optimized you only look once version 5 (YOLOv5) model was developed by incorporating the convolutional block attention module and utilizing the efficient intersection-over-union loss function. The detection performance of the designed algorithm was analyzed. It was found that among different models, the YOLOv5s model exhibited the smallest size and the highest detection speed. Moreover, the optimized YOLOv5 model showed a significant improvement in speed and accuracy for insulator detection, surpassing other methods with a mean average precision of 93.81% and 145.64 frames per second. These results demonstrate the reliability of the improved YOLOv5 model and its practical applicability. [ABSTRACT FROM AUTHOR]

With the construction of smart grid, aerial insulator defect detection based on computer vision has become an important task to ensure grid safety. When the target detection model is too large, it is not conducive to the edge deployment of aerial inspection UAV; Moreover, different aerial photography angles and distances will cause the insulator string in the image to have any direction and less defect information. In order to solve these problems, this paper proposes a rotating GBS-AFP-YOLOv5 model with the combination of lightweight and adaptive features. Firstly, an improved YOLOv5 based on lightweight GBS is proposed by Ghost convolution, which can effectively extract features while reducing the complexity of the model. Then, an adaptive information interaction feature pyramid (AFP) is proposed by combining CARAFE upsampling operator and ECA attention, which effectively fuses the feature information of shallow and deep defects and improves the model performance. Then, a more accurate insulator string detection method is realized by using rotating frame combined with ring label smoothing technology. Finally, the normalized wasserstein distance (NWD) is introduced to improve the loss function, which further enhances the detection ability of the model for small targets with defects. Based on the insulator data set, the test results show that the model has a good defect detection performance, which is improved from mAP0.5 to 0.923 on the basis of only 4.32M parameters. [ABSTRACT FROM AUTHOR]

Topologically associating domain (TAD) boundaries are the flanking edges of TADs, also known as insulated neighborhoods, within the 3D structure of genomes. A prominent feature of TAD boundaries in mammalian genomes is the enrichment of clustered CTCF sites often with mixed orientations, which can either block or facilitate enhancer–promoter (E‐P) interactions within or across distinct TADs, respectively. We will discuss recent progress in the understanding of fundamental organizing principles of the clustered CTCF insulator codes at TAD boundaries. Specifically, both inward‐ and outward‐oriented CTCF sites function as topological chromatin insulators by asymmetrically blocking improper TAD‐boundary‐crossing cohesin loop extrusion. In addition, boundary stacking and enhancer clustering facilitate long‐distance E‐P interactions across multiple TADs. Finally, we provide a unified mechanism for RNA‐mediated TAD boundary function via R‐loop formation for both insulation and facilitation. This mechanism of TAD boundary formation and insulation has interesting implications not only on how the 3D genome folds in the Euclidean nuclear space but also on how the specificity of E‐P interactions is developmentally regulated. [ABSTRACT FROM AUTHOR]

Ceramic insulators on High Voltage Overhead Lines (SUTT) in Indonesia, particularly on the Payakumbuh-Koto Panjang transmission line, are often exposed to natural contamination. This research evaluated the impact of natural contamination on the Total Harmonic Distortion (THD) of leakage current in 150 kV insulators, representing a new approach to understanding insulator performance in contaminated environments. Tests were conducted at the High Voltage Laboratory at Universitas Gadjah Mada using various types of contamination: moss, dust, flashover marks, and clean insulator conditions. The results showed that insulators contaminated with moss exhibited a maximum leakage current of 0.306 mA, with the highest THD reaching 36%, while insulators in clean condition had an average THD of 32.5%. Insulators contaminated with moss, dust, and flashover marks showed THD values of 25.37%, 19.03%, and 28.71%, respectively. Moss and flashover can significantly increase THD, especially when the number of disc-type insulators increases. These findings underscored the importance of a more intensive and targeted maintenance strategy for insulators to minimize the negative impacts of natural contamination, particularly in mountainous areas. This approach contributes to the enhancement of the reliability of high-voltage transmission lines in Indonesia. [ABSTRACT FROM AUTHOR]

Aiming at the problems of a large volume, slow processing speed, and difficult deployment in the edge terminal, this paper proposes a lightweight insulator detection algorithm based on an improved SSD. Firstly, the original feature extraction network VGG-16 is replaced by a lightweight Ghost Module network to initially achieve the lightweight model. A Feature Pyramid structure and Feature Pyramid Network (FPN+PAN) are integrated into the Neck part and a Simplified Spatial Pyramid Pooling Fast (SimSPPF) module is introduced to realize the integration of local features and global features. Secondly, multiple Spatial and Channel Squeeze-and-Excitation (scSE) attention mechanisms are introduced in the Neck part to make the model pay more attention to the channels containing important feature information. The original six detection heads are reduced to four to improve the inference speed of the network. In order to improve the recognition performance of occluded and overlapping targets, DIoU-NMS was used to replace the original non-maximum suppression (NMS). Furthermore, the channel pruning strategy is used to reduce the unimportant weight matrix of the model, and the knowledge distillation strategy is used to fine-adjust the network model after pruning, so as to ensure the detection accuracy. The experimental results show that the parameter number of the proposed model is reduced from 26.15 M to 0.61 M, the computational load is reduced from 118.95 G to 1.49 G, and the mAP is increased from 96.8% to 98%. Compared with other models, the proposed model not only guarantees the detection accuracy of the algorithm, but also greatly reduces the model volume, which provides support for the realization of visible light insulator target detection based on edge intelligence. [ABSTRACT FROM AUTHOR]

Outdoor, real-time, and accurate detection of insulator defect locations can effectively avoid the occurrence of power grid security accidents. This paper proposes an improved GhostNet-YOLOv5s algorithm based on GhostNet and YOLOv5 models. First, the backbone feature extraction network of YOLOv5 was reconstructed with the lightweight GhostNet module to reduce the number of parameters and floating point operations of the model, so as to achieve the purpose of being lightweight. Then, a 160 × 160 feature layer was added to the YOLOv5 network to extract more feature information of small targets and fuzzy targets. In addition, the introduction of lightweight GSConv convolution in the neck network further reduced the computing cost of the entire network. Finally, Focal-EIoU was introduced to optimize the CIoU bounding box regression loss function in the original algorithm to improve the convergence speed and target location accuracy of the model. The experimental results show that the parameter number, computation amount, and model size of the GhostNet-YOLOv5s model are reduced by 40%, 25%, and 36%, respectively, compared with the unimproved YOLOv5s model. The proposed method not only ensures the precision of insulator defect detection, but also greatly decreases the complexity of the model. Therefore, the GhostNet-YOLOv5s algorithm can meet the requirements of real-time detection in complex outdoor environments. [ABSTRACT FROM AUTHOR]

In this paper, a method for detection of crack locations and the width of basin insulators is proposed. Based on the optical frequency domain reflectometry (OFDR) system, the system utilizes an FBG with high feedback for strain as well as temperature, which is affixed to the surface of the tub insulator, and a common single-mode optical fiber, which is used for transmitting data and connected to the optical backscattering reflectometry interrogator. The interrogator measures the backscattered light from the FBG, which varies with temperature or strain. The method has been used to measure the location and width of several different cracks and can locate the crack position with a spatial resolution of 1 mm and measure the crack width with a resolution of 0.77 mm. The method has been used to measure the position and width of insulators. This method provides a simple and fast approach to crack detection in insulators. [ABSTRACT FROM AUTHOR]

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Ceramic and glass insulators as the first generation of insulators are often affected by flashover disturbance during operation. Ceramic insulators coated with semiconducting glaze (SCG) material are then proposed to improve the insulation performance due to warmer surface characteristics that can trigger evaporation on the surface. In this paper, a comparison of insulation performances of semiconducting glaze, ceramic, and glass insulators is discussed from both electrical and non-electrical aspects under various conditions. This comparison aims to distinguish the leakage current characteristics of each insulator during operation. Leakage current tests are conducted to obtain leakage current characteristics of each insulator under artificial conditions of no fog, clean fog, and salt fog. Furthermore, pollutants that are a mixture of NaCl (as equivalent salt deposit density (ESDD)) and kaolin (as non-soluble deposit density (NSDD)) are sprayed onto the insulator surface to see how the pollutant affects the leakage current characteristics of each insulator. The properties of measured leakage current waves are then analyzed, including the waveform, magnitude, and harmonic components. In addition, the non-electrical tests consist of hydrophobicity tests and thermal tests. In the hydrophobicity test, the contact angle formed by a water droplet on the insulator surface is measured, and in the thermal test, temperature differences on the insulator surface before and after voltage applications are compared. The experiment results show that the SCG insulator has a larger leakage current than the other insulators, while the leakage current magnitude of the ceramic and glass insulators is similar. The surface temperature of the SCG insulator is also higher than that of the other insulators due to a larger leakage current. Additionally, the SCG insulator shows better hydrophobicity compared to the other insulators, where all types of insulators show decreased contact angle when pollutants are given. [ABSTRACT FROM AUTHOR]

Transvection is a phenomenon of interallelic communication in which enhancers can activate a specific promoter located on a homologous chromosome. Insulators play a significant role in ensuring functional interactions between enhancers and promoters. In the presented work, we created a model where two or three copies of the insulator are located next to enhancers and promoters localized on homologous chromosomes. Using the Su(Hw) insulator as a model, we showed that the functional interaction between a pair of insulators promotes enhancer–promoter trans-interactions. The interaction between the three insulators, on the contrary, can lead to the formation of chromatin loops that sterically hinder the full enhancer–promoter interaction. The results of the work suggest the participation of insulators in the regulation of homologous chromosome pairing and in communication between distant genomic loci. [ABSTRACT FROM AUTHOR]

Currently, the use of deep learning technologies for detecting defects in transmission line insulators based on images obtained through unmanned aerial vehicle inspection simultaneously presents the problems of insufficient detection accuracy and speed. Therefore, this study first introduced the bidirectional feature pyramid network (BiFPN) module into YOLOv5 to achieve high detection speed as well as enable the combination of image features at different scales, enhance information representation, and allow accurate detection of insulator defect at different scales. Subsequently, the BiFPN module and simple parameter-free attention module (SimAM) were combined to improve the feature representation ability and object detection accuracy. The SimAM also enabled fusion of features at multiple scales, further improving the insulator defect detection performance. Finally, multiple experimental controls were designed to verify the effectiveness and efficiency of the proposed model. The experimental results obtained using self-made datasets show that the combined BiFPN and SimAM model (i.e., the improved BaS-YOLOv5 model) performs better than the original YOLOv5 model; the precision, recall, average precision and F1 score increased by 6.2%, 5%, 5.9%, and 6%, respectively. Therefore, BaS-YOLOv5 substantially improves detection accuracy while maintaining a high detection speed, meeting the requirements for real-time insulator defect detection. [ABSTRACT FROM AUTHOR]

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Copyright of Electric Power Engineering Technology is the property of Editorial Department of Electric Power Engineering Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Integrated Intelligent Energy is the property of Editorial Department of Integrated Intelligent Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Gene expression is often controlled via cis-regulatory elements (CREs) that modulate the production of transcripts. For multi-gene genetic engineering and synthetic biology, precise control of transcription is crucial, both to insulate the transgenes from unwanted native regulation and to prevent readthrough or cross-regulation of transgenes within a multi-gene cassette. To prevent this activity, insulator-like elements, more properly referred to as transcriptional blockers, could be inserted to separate the transgenes so that they are independently regulated. However, only a few validated insulator-like elements are available for plants, and they tend to be larger than ideal. Methods: To identify additional potential insulator-like sequences, we conducted a genome-wide analysis of Utricularia gibba (humped bladderwort), one of the smallest known plant genomes, with genes that are naturally close together. The 10 best insulator-like candidates were evaluated in vivo for insulator-like activity. Results: We identified a total of 4,656 intergenic regions with expression profiles suggesting insulator-like activity. Comparisons of these regions across 45 other plant species (representing Monocots, Asterids, and Rosids) show low levels of syntenic conservation of these regions. Genome-wide analysis of unmethylated regions (UMRs) indicates ~87% of the targeted regions are unmethylated; however, interpretation of this is complicated because U. gibba has remarkably low levels of methylation across the genome, so that large UMRs frequently extend over multiple genes and intergenic spaces. We also could not identify any conserved motifs among our selected intergenic regions or shared with existing insulator-like elements for plants. Despite this lack of conservation, however, testing of 10 selected intergenic regions for insulator-like activity found two elements on par with a previously published element (EXOB) while being significantly smaller. Discussion: Given the small number of insulator-like elements currently available for plants, our results make a significant addition to available tools. The high hit rate (2 out of 10) also implies that more useful sequences are likely present in our selected intergenic regions; additional validation work will be required to identify which will be most useful for plant genetic engineering. [ABSTRACT FROM AUTHOR]

In the past few years, considerable focus has been directed toward the employment of appropriate coatings with the intention of mitigating imperfections brought about by various factors including UV radiation, humidity, and particulate matter within the insulation framework. Employing an appropriate polymer coating to preserve the characteristics of insulating materials can prove to be an effective remedy within this domain. Polymer composites have emerged as viable substitutes for ceramic insulation, owing to their distinctive characteristics such as lightweight composition, hydrophobic surface properties, thermal and dielectric attributes, as well as superior resistance to vandalism. Typically, polymer insulation comprises two primary components: the insulating core, commonly composed of materials like fiber or epoxy, and the secondary part, which incorporates elastomeric substances such as ethylene propylene diene monomer (EPDM) and Polydimethylsiloxane (PDMS). The use of silicone contributes to the prolonged retention of surface properties, primarily due to the chemical stability inherent in the polymer chains. Silicone-based insulators, characterized by their low surface energy and resulting hydrophobic surface, prove to be more suitable in wet conditions. However, these materials are susceptible to degradation from environmental factors such as temperature, humidity, and Ultraviolet (UV) radiation. An inherent challenge with composite insulators lies in their aging process. Various strategies are employed to enhance polymer properties, involving mixing, composition adjustments, and the incorporation of diverse additives to improve specific material characteristics. This discussion outlines factors influencing insulator efficiency and explores various methods for enhancing the performance of polymer insulators, with a focus on hydrophobic and superhydrophobic surfaces. [ABSTRACT FROM AUTHOR]

This article summarizes the research progress of the application of silicone materials in composite insulators, anti-pollution flashover coatings, cable accessories, anti-corrosion coatings, electric insulating oil and other materials, and looks forward to the development prospects of silicone materials in the field of power. [ABSTRACT FROM AUTHOR]

Chromatin architecture is critical for the temporal and tissue-specific activation of genes that determine eukaryotic development. The functional interaction between enhancers and promoters is controlled by insulators and tethering elements that support specific long-distance interactions. However, the mechanisms of the formation and maintenance of long-range interactions between genome regulatory elements remain poorly understood, primarily due to the lack of convenient model systems. Drosophila became the first model organism in which architectural proteins that determine the activity of insulators were described. In Drosophila, one of the best-studied DNA-binding architectural proteins, Su(Hw), forms a complex with Mod(mdg4)-67.2 and CP190 proteins. Using a combination of CRISPR/Cas9 genome editing and attP-dependent integration technologies, we created a model system in which the promoters and enhancers of two reporter genes are separated by 28 kb. In this case, enhancers effectively stimulate reporter gene promoters in cis and trans only in the presence of artificial Su(Hw) binding sites (SBS), in both constructs. The expression of the mutant Su(Hw) protein, which cannot interact with CP190, and the mutation inactivating Mod(mdg4)-67.2, lead to the complete loss or significant weakening of enhancer–promoter interactions, respectively. The results indicate that the new model system effectively identifies the role of individual subunits of architectural protein complexes in forming and maintaining specific long-distance interactions in the D. melanogaster model. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of an environment-friendly process for synthesizing nanoparticles in the field of bionanotechnology is growing day-by-day. Increasing drug resistance in microbes has compelled researchers to synthesize biologically active nanoparticles. In this study, we used Tribulus terrestris plant extract to synthesize CuO/NaCuSO4 nanocomposite. The synthesized samples were characterized through functional groups analysis of FTIR and morphological analysis of SEM. The X-ray diffraction (XRD) and ultra-visible light absorbance analysis (UV–vis) were used to find the nanocrystalline nature and bandgap energy of the biosynthesized copper oxide (CuO) nanoparticles, respectively. In the metal oxide region of Fourier transform infrared (FTIR) spectroscopy the copper oxide nanoparticles were confirmed at 523 cm−1 which showed the nature of plant extracts to control over the reduction and stabilizing of the nanoparticles. The Rietveld refinement analysis yielded unit cell compositions of 53.39% for CuO and 46.61% for NaCuSO4, respectively. The monoclinic structure of CuO was confirmed, and the crystalline size was calculated as 37 nm by XRD analysis. From UV–vis spectroscopy, the absorption peak was observed at 277 and 337 nm, revealing the presence of CuO nanoparticles. In fact, the cluster-like morphology patterns are captured by scanning electron microscopy (SEM) and particle sizes were observed around 102 nm. Finally, the dielectric properties of the synthesized copper oxide nanoparticles have been examined and reported in detail. [ABSTRACT FROM AUTHOR]

Insulators are crucial insulation components and structural supports in power grids, playing a vital role in the transmission lines. Due to temperature fluctuations, internal stress, or damage from hail, insulators are prone to injury. Automatic detection of damaged insulators faces challenges such as diverse types, small defect targets, and complex backgrounds and shapes. Most research for detecting insulator defects has focused on a single defect type or a specific material. However, the insulators in the grid's transmission lines have different colors and materials. Various insulator defects coexist, and the existing methods have difficulty meeting the practical application requirements. Current methods suffer from low detection accuracy and mAP0.5 cannot meet application requirements. This paper proposes an improved you only look once version 7 (YOLOv7) model for multi-type insulator defect detection. First, our model replaces the spatial pyramid pooling cross stage partial network (SPPCSPC) module with the receptive filed block (RFB) module to enhance the network's feature extraction capability. Second, a coordinate attention (CA) mechanism is introduced into the head part to enhance the network's feature representation ability and to improve detection accuracy. Third, a wise intersection over union (WIoU) loss function is employed to address the low-quality samples hindering model generalization during training, thereby improving the model's overall performance. The experimental results indicate that the proposed model exhibits enhancements across various performance metrics. Specifically, there is a 1.6% advancement in mAP_0.5, a corresponding 1.6% enhancement in mAP_0.5:0.95, a 1.3% elevation in precision, and a 1% increase in recall. Moreover, the model achieves parameter reduction by 3.2 million, leading to a decrease of 2.5 GFLOPS in computational cost. Notably, there is also an improvement of 2.81 milliseconds in single-image detection speed. This improved model can detect insulator defects for diverse materials, color insulators, and partial damage shapes in complex backgrounds. [ABSTRACT FROM AUTHOR]

The present paper deals with new modeling to reproduce the electric discharge in the rod-plane air gap system with rubber insulating barrier under AC and impulse voltage. This model considers the randomness character of discharge evolution which is governed by the electric field. The discharges shape obtained by this model are compared with ones given by experimental tests. The established model reproduces correctly the forms of discharges obtained by experimental tests under AC voltage. It is found that the behavior of the electrical discharge depends not only on the dimension (thickness and width) of the insulating barriers but on its positions in the air gap as well. It is to highlight that the mode of applied voltage is of key importance barrier. Experimental investigation shows that the developed arc can evolve on 1 to 4 channels. The generated discharges in AC voltage distinguish by the formation of a multiple-channel arc. Whereas, the discharge under lightning impulse voltage found to progress in a single channel whatever the barrier position and dimensions. The model confirms that electric field is the most important factor in the behavior of the rodinsulating barrier-plane system submitted to high voltage. [ABSTRACT FROM AUTHOR]

In this work, a study on a cap and pin insulator (1512L) is proposed to evaluate the distribution of the electric field and the potential along the insulator under different conditions. A computational and experimental study for the examination of a real insulators model is assessed. Tests on contaminated insulators in the laboratory under the suggested conditions have been carried out. Finite element methods (FEM) have been employed in the numerical analysis to assess the electrical properties of the insulator under the suggested contamination profiles, including potential and electric field. The study proposed in this paper provides an effective and practical tool for analysis and enhance the dielectric properties of the studied insulator. [ABSTRACT FROM AUTHOR]

Insulators on overhead power lines have long been exposed to the outdoors and are susceptible to pollution and salt contamination. Due to factors such as wind and gravity, pollution in the atmosphere gradually deposits on the surface of the insulator. In humid and windy conditions, conductive pollutants begin to dissolve in the water on the surface of the insulator, increasing the leakage current and affecting insulation performance. This study mainly uses a data acquisition system to measure the leakage current of the insulator and weather parameters (including temperature, relative humidity, pressure, wind speed, and ultraviolet) around the insulator. Artificial intelligence is then applied to establish a prediction model for leakage current based on weather parameters. The established model accurately predicts insulator leakage current through weather parameters. In order to observe the real-time status of the insulator, this study establishes a monitoring platform that integrates the predicted leakage current with weather parameters. It allows users or maintenance personnel to connect to the server through the network to observe the predicted results and weather parameters. The results can establish a real-time salt contamination monitoring system for insulators on transmission lines, enabling operation and maintenance personnel to understand the actual insulation situation of the insulator in real-time. This can not only prevent power outages due to salt contamination or pollution but also reduce the workload for maintenance personnel. Moreover, the maintenance strategy is upgraded from time-base maintenance to condition-base maintenance, significantly improving the efficiency of operation and maintenance for power lines. [ABSTRACT FROM AUTHOR]

Insulators play a pivotal role in the reliability of power distribution networks, necessitating precise defect detection. However, compared with aerial insulator images of transmission network, insulator images of power distribution network contain more complex backgrounds and subtle insulator defects, it leads to high false detection rates and omission rates in current mainstream detection algorithms. In response, this study presents ID-YOLOv7, a tailored convolutional neural network. First, we design a novel Edge Detailed Shape Data Augmentation (EDSDA) method to enhance the model's sensitivity to insulator's edge shapes. Meanwhile, a Cross-Channel and Spatial Multi-Scale Attention (CCSMA) module is proposed, which can interactively model across di􀀀erent channels and spatial domains, to augment the network's attention to high-level insulator defect features. Second, we design a Re-BiC module to fuse multi-scale contextual features and reconstruct the Neck component, alleviating the issue of critical feature loss during inter-feature layer interaction in traditional FPN structures. Finally, we utilize the MPDIoU function to calculate the model's localization loss, e􀀀ectively reducing redundant computational costs. We perform comprehensive experiments using the Su22kV_broken and PASCAL VOC 2007 datasets to validate our algorithm's e􀀀ectiveness. On the Su22kV_broken dataset, our approach attains an 85.7% mAP on a single NVIDIA RTX 2080ti graphics card, marking a 7.2% increase over the original YOLOv7. On the PASCAL VOC 2007 dataset, we achieve an impressive 90.3%mAP at a processing speed of 53 FPS, showing a 2.9% improvement compared to the original YOLOv7. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Isolators are one of the assets at PT PLN, which serve as separators between the energized and non-energized parts. Maintenance is performed by replacing damaged isolators when there are indications of reduced insulation resistance. In this journal, the insulation resistance values were measured using a Kyoritsu Insulation Tester and six porcelain isolator samples in various conditions were used. The aim was to determine the extent of the decrease in insulation resistance values, as well as the leakage current and touch voltage values based on Ohm's law formula. Based on the measurement results, the sixth isolator in partially damaged condition is the worst, supported by an insulation resistance value of 800 MΩ for a test voltage of 10kV and 400 MΩ for a test voltage of 5kV. In good condition, the measured insulation resistance value of the isolator is 1 TΩ. Based on the calculation results, in the sixth condition, the leakage current values were 6.25 mA and 25 mA, and the touch voltage values, assuming an average human insulation resistance value of 1000 Ω, were 6.25 Volts and 25 Volts. According to 0520-2.K.DIR.2014 standards, the insulation resistance values meet the requirement that 1kV insulation resistance can be sustained by 1MΩ and are still below the maximum touch voltage limit, which is < 50V effective. [ABSTRACT FROM AUTHOR]

Regardless of the environment, the power system network must be continuously operational. Current spacer failures of Gas Insulated Busduct (GIB) have been noted as a result of a number of manufacturing and switching faults, including delamination, protrusion, depression, gap, etc. These defects have a severe negative effect on the insulator's surface, which de-energises the gas-insulated busduct device and causes a significant financial loss. For the purpose of studying the electric stress at the Triple Junction, a Functionally Graded Material (FGM) spacer is built for a three phase GIB with protrusion irregularity in this work. The stress is reduced by inserting metal inserts at the end of the zero potential. Functionally graded materials are spatially distributed with numerous filler materials to achieve homogeneous electric field stress by doping them with various permittivity values. The spacer used in the simulation is made to withstand a range of voltages as well as varied FGM gradings. Grading's impact on electric field stress is identified and further diminished with the addition of the MI to the FGM insulator. The outcomes are discussed and analysed to demonstrate how well the proposed spacer works. [ABSTRACT FROM AUTHOR]

We analyze the propagation of two-dimensional dispersive and relativistic wavepackets localized in the vicinity of the zero level set T of a slowly varying domain wall modeling the interface separating two insulating media. We propose a semiclassical oscillatory representation of the propagating wavepackets and provide an estimate of their accuracy in appropriate energy norms. We describe the propagation of relativistic modes along T and analyze dispersive modes by a stationary phase method. In the absence of turning points, we show that arbitrary smooth localized initial conditions may be represented as a superposition of such wavepackets. In the presence of turning points, the results apply only for sufficiently high-frequency wavepackets. The theory finds applications for both Dirac systems of equations modeling topologically nontrivial systems as well as Klein--Gordon equations, which are topologically trivial. [ABSTRACT FROM AUTHOR]

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Insulators find extensive use across diverse facets of power systems, playing a pivotal role in ensuring the security and stability of electrical transmission. Detecting insulators is a fundamental measure to secure the safety and stability of power transmission, with precise insulator positioning being a prerequisite for successful detection. To overcome challenges such as intricate insulator backgrounds, small defect scales, and notable differences in target scales that reduce detection accuracy, we propose the AC-YOLO insulator multi-defect detection network based on adaptive attention fusion. To elaborate, we introduce an adaptive weight distribution multi-head self-attention module designed to concentrate on intricacies in the features, effectively discerning between insulators and various defects. Additionally, an adaptive memory fusion detection head is incorporated to amalgamate multi-scale target features, augmenting the network's capability to extract insulator defect characteristics. Furthermore, a CBAM attention mechanism is integrated into the backbone network to enhance the detection performance for smaller target defects. Lastly, improvements to the loss function expedite model convergence. This study involved training and evaluation using publicly available datasets for insulator defects. The experimental results reveal that the AC-YOLO model achieves a notable 5.1% enhancement in detection accuracy compared to the baseline. This approach significantly boosts detection precision, diminishes false positive rates, and fulfills real-time insulator localization requirements in power system inspections. [ABSTRACT FROM AUTHOR]

Insulators, pivotal to the integrity of railway catenaries, demand impeccable functioning to prevent system failures. Their consistent assessment is vital for railway safety. Current insulator evaluations in subways predominantly involve human intervention, a method fraught with inefficiencies, inaccuracies, and oversights, exacerbated by the complex backdrop of subway tunnels and minuscule defect dimensions. This study introduces an enhanced algorithm, anchored in the YOLOv5 framework, to refine insulator defect identification. Challenges in defect detection include limited, imbalanced data samples and adaptability. Addressing this, an accurate catenary model mirrors the subway line's architecture, facilitating the creation of synthetic instances of both intact and impaired insulators. An atomization technique augments the dataset volume, fortifying the algorithm's resilience in reduced visibility conditions, such as fog. Tackling sample equilibrium, the study introduces an equilibrium loss function, assigning disparate weights to various sample categories during training, thereby sharpening the algorithm's focus on positive instances, particularly those that are challenging to discern, and rectifying the disproportion in sample categories. Incorporating lightweight structures like GhostNet and the Efficient Channel Attention Network (ECA-Net) channel attention scheme not only diminishes the network's computational demands, thereby elevating the detection capabilities, but also minimizes superfluous data processing, enhancing the accuracy in identifying smaller targets. Empirical analyses indicate substantial model optimization: a size reduction to 60 pp of its original (from 15 MB to 9 MB), a near 1.4 pp increase in mean average precision (mAP) to 96.57%, and a tripling of the detection speed (from 30 to 90 FPS). Real-world image assessments further reveal a mAP improvement of approximately 2.5 pp (reaching 98.43%), confirming the model's suitability for real-time applications. [ABSTRACT FROM AUTHOR]

The transcriptome data of skin cells from domestic cats with brown, orange, and white coats were analyzed using a public database to investigate the possible relationship between coat color‐related gene expression and squamous cell carcinoma risk, as well as the mechanism of deafness in white cats. We found that the ratio of the expression level of genes suppressing squamous cell carcinoma to that of genes promoting squamous cell carcinoma might be considerably lower than the theoretical estimation in skin cells with orange and white coats in white‐spotted cat. We also found the possibility of the frequent production of KIT lacking the first exon (d1KIT) in skin cells with white coats, and d1KIT production exhibited a substantial negative correlation with the expression of SOX10, which is essential for melanocyte formation and adjustment of hearing function. Additionally, the production of d1KIT was expected to be due to the insulating activity of the feline endogenous retrovirus 1 (FERV1) LTR in the first intron of KIT by its CTCF binding sequence repeat. These results contribute to basic veterinary research to understand the relationship between cat skin coat and disease risk, as well as the underlying mechanism. [ABSTRACT FROM AUTHOR]

Topological insulators are materials that in bulk mode have band gap such as an ordinary insulator but can protect the conduction mode at the edge or surface, i.e. apart from a simple and insulated metal. These materials are insulator in their bulk modes but are metal at the surface. Topological insulators are developed in two and three dimensions. Recently, compounds of the Bi2Se3 have attracted a huge attention because of existence of a Dirac cone in their surface state, having a suitable bandgap (0.3 eV), and easy santhesis. In this research, we investigate the properties of this material using density functional theory. The main focus is on bulk calculations and surface properties. The band structure of this material is studied in bulk mode without any consideration of spin - orbit interaction. Then a surface of this material is considered and its band structure and density of states are studied. The results show that the surface of this material has a Dirac cone. [ABSTRACT FROM AUTHOR]

Drosophila CP190 and CP60 are transcription factors that are associated with centrosomes during mitosis. CP190 is an essential transcription factor and preferentially binds to housekeeping gene promoters and insulators through interactions with architectural proteins, including Su(Hw) and dCTCF. CP60 belongs to a family of transcription factors that contain the N-terminal MADF domain and the C-terminal BESS domain, which is characterized by the ability to homodimerize. In this study, we show that the conserved CP60 region adjacent to MADF is responsible for interacting with CP190. In contrast to the well-characterized MADF-BESS transcriptional activator Adf-1, CP60 is recruited to most chromatin sites through its interaction with CP190, and the MADF domain is likely involved in protein–protein interactions but not in DNA binding. The deletion of the Map60 gene showed that CP60 is not an essential protein, despite the strong and ubiquitous expression of CP60 at all stages of Drosophila development. Although CP60 is a stable component of the Su(Hw) insulator complex, the inactivation of CP60 does not affect the enhancer-blocking activity of the Su(Hw)-dependent gypsy insulator. Overall, our results indicate that CP60 has an important but redundant function in transcriptional regulation as a partner of the CP190 protein. [ABSTRACT FROM AUTHOR]

Featured Application: The results of this paper can be instrumental in establishing insulation material management standards for determining the stable operation condition of XLPE cables in the future. Cross-linked polyethylene (XLPE) cable is a representative power transmission cable. XLPE has excellent mechanical properties, chemical and heat resistance, and insulation. However, XLPE insulation deteriorates during operation due to electrical, mechanical, and thermal stresses. Among these, thermal stress is a major factor and reduces insulation properties due to a change in molecular structure. Therefore, XLPE characteristic evaluation by heat exposure is essential for power cable condition evaluation. Herein, deteriorated XLPE samples were characterized by tensile strength, X-ray diffraction, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and ultraviolet-visible spectroscopy after exposure to various temperatures and durations. Comparing the tensile strength with other analysis results yielded correlations. Each characteristic showed a linear relationship. The correlation between tensile strength and carbonyl index was the strongest, and the coefficient of determination, R2, was 0.9299. Therefore, these results will provide important information on chemical properties when establishing operational management standards for XLPE insulators in the future. [ABSTRACT FROM AUTHOR]

In order to achieve the real-time detection of contamination components on the surface of insulators and explore the impact of different insulators on the identification of contamination components, a hyperspectral remote sensing imaging technology based on feature band score evaluation has been proposed. The data of single fouling components for silicone rubber and ceramics has been collected by hyperspectral imaging technology, and the spectral lines are pre-processed using a model of spectral spatial adaptive total variation and a model of fouling component classification and identification based on the maximum correlation of spectral line features, which was established by a maximum correlation-minimum redundancy-back propagation neural network. The spectral spatially adaptive total variance model was able to denoise and smooth the hyperspectral curves, and obtain hyperspectral images that built a classification and recognition model. The model of maximum correlation-minimum redundancy-back propagation neural network used the fractional ranking of the spectral feature bands as the basis for filtering features, and the classification model is high accuracy, up to 92. 5% for contamination components with silicone rubber substrates and 80% for fouling components using ceramic substrates. The classification of contamination components in the hyperspectrum varies between different types of insulators as background substrates, mainly due to the degree of coverage of the fouling layer and the shape of the fouling particles; it is necessary to avoid thin areas of the fouling layer to reduce the background substrate on the detection results. [ABSTRACT FROM AUTHOR]

Acoustic inspection is a valuable technique that can detect early stage defects in equipment, thereby facilitating predictive maintenance. In recent times, ultrasonic sensors have made detecting partial discharges through acoustic sensing increasingly feasible. However, interpreting the acoustic signals can pose challenges, as it requires extensive expertise and knowledge of equipment configuration. To address this issue, a technique based on zero-crossing rate and fundamental frequency estimation has been proposed to standardize insulator diagnosis. In an experiment involving a database of 72 raw acoustic signals with frequencies ranging from 0 to 128 kHz, various types of pollution and defects were introduced to a chain of insulators. By employing the proposed technique, the occurrence of partial discharges can be detected and classified according to type, such as corona or surface discharges. This advanced approach to diagnosis simplifies the process while providing valuable insights into the severity of observed phenomena in the field. [ABSTRACT FROM AUTHOR]

Railway system insulators are affected by pollution, altitude, and other environmental situations during operation, which causes reduced electrical performance or even flashover accidents. These factors threaten the safety of railway operations in high-altitude areas. However, the natural contamination characteristics of a railroad in a plateau area is still unclear. In this study, a natural pollution accumulation test for railway insulators in a high-altitude area was carried out, and the distribution rules of nonsoluble deposit density (NSDD), equivalent salt deposit density (ESDD), NSDD/ESDD ratio, and nonuniformity (T/B) of the pollution distribution of the tested insulators were calculated. Meanwhile, the chemical compositions of the pollution from different test sites were analyzed. The differences of pollution accumulation between railway insulators and suspended insulators of a power system and the influencing factors were compared and analyzed by combining with a numerical simulation. The results show that the pollution level of railroad insulators is mainly distributed in level b and above. A pollution sample is mainly composed of sodium chloride, while the NSDD/ESDD ratio of pollution is mostly distributed from 0 to 5, with T/B value ranges from 1/0.62 to 1/1.76. The amount of insulator contamination is influenced by the location inside and outside the tunnel. Additionally, the pollution amount is influenced by the structure and type of insulators. Finally, this paper studies the creepage distance and structural height required by railway insulators in a plateau area according to the natural pollution accumulation characteristics of railway insulators, which can provide a reference for a railway electrical external insulation configuration in a high-altitude area. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In higher eukaryotes, distance enhancer-promoter interactions are organized by topologically associated domains, tethering elements, and chromatin insulators/boundaries. While insulators/boundaries play a central role in chromosome organization, the mechanisms regulating their functions are largely unknown. In the studies reported here, we have taken advantage of the well-characterized Drosophila bithorax complex (BX-C) to study one potential mechanism for controlling boundary function. The regulatory domains of BX-C are flanked by boundaries, which block crosstalk with their neighboring domains and also support long-distance interactions between the regulatory domains and their target gene. As many lncRNAs have been found in BX-C, we asked whether readthrough transcription (RT) can impact boundary function. For this purpose, we took advantage of two BX-C boundary replacement platforms, Fab-7attP50 and F2attP, in which the Fab-7 and Fub boundaries, respectively, are deleted and replaced with an attP site. We introduced boundary elements, promoters, and polyadenylation signals arranged in different combinations and then assayed for boundary function. Our results show that RT can interfere with boundary activity. Since lncRNAs represent a significant fraction of Pol II transcripts in multicellular eukaryotes, it is therefore possible that RT may be a widely used mechanism to alter boundary function and regulation of gene expression. [ABSTRACT FROM AUTHOR]

At this stage, the inspection of transmission lines is dominated by UAV inspection. Insulators, as essential equipment for transmission line equipment, are susceptible to various factors during UAV detection, and their detection results often lead to leakages and false detection. Combining deep learning detection algorithms with the UAV transmission line inspection system can effectively solve the current sensing problem. To improve the recognition accuracy of insulator detection, the MS-COCO pre-training strategy that combines the FPN module with a cascading R-CNN algorithm based on the ResNeXt-101 network is proposed. The purpose of this paper is to systematically and comprehensively analyze mainstream isolator detection algorithms at the current stage and to verify the effectiveness of the improved Cascade R-CNN X101 model by combining the mAP (mean Average Precision) value and other related evaluation indices. Compared with Faster R-CNN, Retina Net, and other detection algorithms, the model is highly accurate and can effectively deal with the false detection, leakage, and non-recognition of the environment in online special detection. The research in this paper provides a new idea for intelligent fault detection of transmission line insulators and has some reference value for engineering applications. [ABSTRACT FROM AUTHOR]

Operation accidents caused by deteriorated insulators occur from time to time, which poses a direct threat to the safe and stable operation of transmission lines. Much research has been done at home and abroad on the degradation mechanism of deteriorated insulators, the electric field distribution characteristics of insulator strings and the influence of deteriorated insulators on the space electric field, but there is little research on the influence of three-phase electrification on the space electric field of insulator strings. Therefore, this paper studies the simulation and detection of electric field distribution of deteriorated insulators in three-phase transmission lines. First, the difference between three-phase electrification and single-phase electrification on the space electric field of insulator strings is simulated and analyzed, and the influence of deteriorated insulators on the space electric field distribution of insulator strings under three-phase electrification is studied. Second, based on simulation results, a detection method for deteriorated insulators in three-phase overhead trans-mission lines is proposed, and a non-contact space electric field measurement device based on Unmanned Aerial Vehicle (UAV) is developed. Finally, a Unmanned Aerial Vehicle inspection system is used to test the transmission lines in combination with an electric power department, and the simulation results and the effectiveness of the proposed detection method are verified. Results show the electric field distribution of insulator strings is obviously different between three-phase electrification and single-phase electrification, and when the detection distance is 300 mm, the proposed detection method and device can effectively identify deteriorated insulators in three-phase transmission lines. [ABSTRACT FROM AUTHOR]

The condensation mechanism of the insulators' surface, increase the surface electrical conductivity. The electrical conductivity of the insulator creates a high level of leakage current and causes the failure. Difference between the dew point and the surface temperature of the insulator which occur due to radiative cooling mechanism, is the major reason of the moisture condensation on the polluted insulator surface. To compensate for the temperature difference, carbon nanotubes (CNTs) are being added to the silicone rubber housing material. The main idea of this research is based on generating joule heating by reducing the surface resistance of high voltage insulators. For this purpose, a developed model based on Halpin–Tsai formulation for tensile modulus of nanocomposites is joined with the conventional power-law model for the effective electrical conductivity of silicone rubber matrix carbon nanotube composite (SMCNT). SMCNT samples are prepared with the addition of various CNT volume fractions to high temperature vulcanizing (HTV) silicone rubber by melt-blending method. The developed model reveals that the high fraction of thinner and longer CNT, thicker interphase, higher concentration of percolated CNT, lower waviness of CNT, and higher conductivity of CNT can make a higher effective conductivity for SMCNT. [ABSTRACT FROM AUTHOR]

Insulators are architectural elements implicated in the organization of higher-order chromatin structures and transcriptional regulation. However, it is still unknown how insulators contribute to Drosophila telomere maintenance. Although the Drosophila telomeric retrotransposons HeT-A and TART occupy a common genomic niche, they are regulated independently. TART elements are believed to provide reverse transcriptase activity, whereas HeT-A transcripts serve as a template for telomere elongation. Here, we report that insulator complexes associate with TART and contribute to its transcriptional regulation in the Drosophila germline. Chromatin immunoprecipitation revealed that the insulator complex containing BEAF32, Chriz, and DREF proteins occupy the TART promoter. BEAF32 depletion causes derepression and chromatin changes at TART in ovaries. Moreover, an expansion of TART copy number was observed in the genome of the BEAF32 mutant strain. BEAF32 localizes between the TART enhancer and promoter, suggesting that it blocks enhancer-promoter interactions. Our study found that TART repression is released in the germ cysts as a result of the normal reduction of BEAF32 expression at this developmental stage. We suggest that coordinated expression of telomeric repeats during development underlies telomere elongation control. [ABSTRACT FROM AUTHOR]

Composition and structure are the two most essential factors for insulator materials performance. In this paper, the differences in composition, structure and mechanical properties of three typical alumina insulator for ultra high voltage direct current (UHVDC) were systematically studied, and the reasons were analyzed. The results show that compared with NGK, two domestic manufacturers have added more calcined industrial alumina, less potash feldspar and quartz into the formula, and have not properly raised the sintering temperature according to the formula, the porcelains of two domestic manufacturers show the following characteristic: 1) the content of Al2O3 are 47.22% and 45.24%, respectively, 7.31% and 5.33% higher than that of NGK, the content of SiO2 are 46.32% and 48.44%, respectively, 7.09% and 4.97% lower than that of NGK, and the total content of K2O + Na2O are 3.21% and 3.14%, respectively, 0.41% and 0.48% lower than that of NGK; 2) the true porosity are 5.24% and 4.18%, respectively, 3.46% and 4.52% lower than that of NGK. The internal pores are basically less than 5 µm, and the pore size is generally smaller. There are many flat, slender, crack like pores, as well as annular pores and cracks surrounding the particles; 3) the content of internal crystalline phase is 48.10% and 49.04%, respectively, which is nearly 10% higher than NGK, with corundum phase being 10% higher, quartz phase being 4% higher, mullite phase being 4% less. The mullite phase is thinner and shorter, and the degree of crosslinking is lower; 4) the average value of the three-point bending strength of the porcelain head test strip are 155 and 158 MPa, respectively, which are higher than NGK, but the dispersion strength of the two domestic manufacturers is higher than NGK. [ABSTRACT FROM AUTHOR]