Types Of Cables Research Articles

Crystal structures of cables formed by the acetylated and unacetylated forms of the Schizosaccharomyces pombe tropomyosin orthologue TpmCdc8

Cables formed by head-to-tail polymerization of tropomyosin, localized along the length of sarcomeric and cytoskeletal actin filaments, play a key role in regulating a wide range of motile and contractile processes. The stability of tropomyosin cables, their interaction with actin filaments and the functional properties of the resulting co-filaments are thought to be affected by N-terminal acetylation of tropomyosin. Here, we present high–resolution structures of cables formed by acetylated and unacetylated Schizosaccharomyces pombe tropomyosin orthologue TpmCdc8. The crystal structures represent different types of cables, each consisting of TpmCdc8 homodimers in a different conformation. The structures show how the interactions of the residues in the overlap junction contribute to cable formation and how local structural perturbations affect the conformational dynamics of the protein and its ability to transmit allosteric signals. In particular, N-terminal acetylation increases the helicity of the adjacent region, which leads to a local reduction in conformational dynamics and consequently to less fraying of the N-terminal region. This creates a more consistent complementary surface facilitating the formation of specific interactions across the overlap junction.

Optimization of monitoring systems power cable lines

RELEVANCE. The length and complexity of the geography of medium voltage cable lines is at a high level. Such lines extend underground, on supports in the air. In order to constantly maintain the reliability of city power supply at a high level, any interruptions and accidents should be promptly corrected.TARGET. The main goal of the work is to develop the theory of medium voltage CL research, to practically and theoretically substantiate the search for the most convenient and effective installation for CL diagnostics, to study and develop possible modifications of CL diagnostic installations.METHODS. A variant of CL diagnostics based on the CPDA-60 installation is proposed, which makes it possible to find and localize the places where defects occur in the insulation based on the measurement and analysis of partial discharges (PD). Suitable for insulation monitoring in all types of high voltage cables. The CPDA installation can be used when testing new cable lines being put into operation, and to analyze the condition of old cables in operation.RESULTS. Cable lines require an integrated approach to diagnostics and monitoring, since the reliability of modern authentication systems for the generation and distribution of electricity is largely determined by the electrical reliability of electrical equipment. Technical diagnostics of equipment is a key link, the quality of which determines the efficiency of the processes of organizing production activities, strategic planning and renovation of electric grid assets.CONCLUSION. The study and analysis of the presented data and research allows us to form a conclusion regarding the method of measuring and localizing partial discharges (PD) in power cable lines (CL) using the Online Wire Testing System (OWTS) diagnostic system. The OWTS system allows real-time measurements without interrupting cable lines, making it especially valuable to the energy industry. Thanks to the introduction of advanced technologies and signal processing algorithms, the method has high accuracy and sensitivity to minimal manifestations of private discharges, which allows not only to detect, but also to accurately localize the location of defects in the insulation. The use of this method can significantly increase the service life of power cables, reduce the likelihood of sudden accidents and, as a result, reduce the cost of repair and maintenance of electrical power equipment. Ultimately, improvements in diagnostic and monitoring techniques, including the method of measuring and localizing PD in power lines using OWTS, represent a significant step towards improving the reliability and safety of electrical power systems. This will not only reduce operating costs, but also ensure uninterrupted and high-quality power supply to consumers.

Measurement of the Tension Loss in a Cable Traveling Over a Pulley, for Low-Speed Applications

BackgroundWire ropes or cables are widely used solutions for force transmission in several industrial applications. Their hysteretic behavior may significantly influence control accuracy or the force transmission’s efficiency. Cables traveling through sheaves can suffer a relatively high tension loss, which this article addresses.ObjectiveThis paper aims to present a simple measurement method for the tension loss in cables traveling over sheaves on bearings.MethodsThe presented measurement method uses a cable-pulley system with a spring installed at one cable end. The pulley is moved in a zig-zag pattern. The force is measured on both cable ends; this way, the tension loss can be determined as a function of the cable tension. The force was measured with S-type load cells, which are highly sensitive to off-axis loads; this problem can be overcome by proving that the force measurement has a proportional error, which can be eliminated from the frictional coefficient. The measurements are compared to two models from the literature; one approximates the power loss of a cable drive by calculating the work of the cable’s inner friction, and the other is a cable bending model, which is used to determine the hysteretic energy of the cyclic bending.ResultsThe result of the measurement evaluation is a coefficient of tension loss that contains the loss coming from the cable bending and the bearing friction. Four cable types and a steel strip with negligible bending hysteresis were measured, the latter for control measurement. It is demonstrated that a significant part of the tension loss originates from the inner friction of the cable and that it is equal to the hysteretic energy of the cyclic bending.ConclusionThe presented method provides a robust measurement for the tension loss factor in cables traveling over pulleys. It is proven that the off-axis loads cause a proportional error in the force measured by S-type load cells, and this measurement error can be eliminated from the tension loss factor. The results demonstrated that the presented models can be used to predict the tension loss in cables traveling over sheaves.

Floating photovoltaic systems: photovoltaic cable submersion testing and potential impacts.

Floating photovoltaics (FPV) is an emerging technology that is gaining attention worldwide. However, little information is still available on its possible impacts in the aquatic ecosystems, as well as on the durability of its components. Therefore, this work intends to provide a contribution to this field, analysing possible obstacles that can compromise the performance of this technology, adding to an increase of its reliability and assessing possible impacts.The problem under study is related to the potential submersion of photovoltaic cables, that can lead to a degradation of its electrical insulation capabilities and, consequently, higher energy production losses and water contamination. In the present study, the submersion of photovoltaic cables (with two different insulation materials) in freshwater and artificial seawater was tested, in order to replicate real life conditions, when FPV systems are located in reservoirs or in the marine environment. Electrical insulation tests were carried out weekly to assess possible cable degradation, the physical-chemical characteristics of the water were also periodically monitored, complemented by analysis to detect traces of copper and microplastics in the water. The results showed that the submersion of photovoltaic cables with rubber sheath in saltwater can lead to a cable accelerated degradation, with reduction of its electrical insulation and, consequently, copper release into the aquatic environment. The test results pointed a probable relationship between submersion of cables with rubber outer shell and water freezing temperatures and the occurrence of accelerated degradation of the cable insulation layer. Reduced insulation resistance values were measured in this cable type after the occurrence of such temperatures, both in salt and freshwater, the cable presented visible exterior degradation signs. For this case copper residues were detected in the water.

Research on the Capacity Allocation and Planning Model of a Flexible Direct Current Transmission System Based on Swarm Intelligence Optimization Algorithm

Based on the contradiction between the increasing power demand and the low capacity of the traditional direct current (DC) transmission system, this study innovatively combines the swarm intelligence optimization algorithm with power transmission and storage, and establishes a flexible DC transmission system model based on the swarm intelligence optimization algorithm. The study also analyzes the difference between the optimized capacity configuration of flexible DC transmission system and the traditional transmission system under different factors. The research results show that the transmission mode has become an important factor affecting the capacity allocation of flexible DC transmission system. The transmission medium and transmission cable type also have an impact on the capacity allocation of flexible DC transmission system. Optimizing power transmission mode, changing transmission medium and whether to add the swarm intelligence optimization algorithm are of far-reaching significance for improving the capacity allocation of flexible DC transmission system.

Analysis of bond strength of CFRP cables with concrete using random forest model

The use of carbon fiber-reinforced polymer (CFRP) as an alternative to steel tendons in prestressed concrete is increasingly favored due to its non-corrosive properties. A critical aspect of this substitution is the bond strength required to effectively transfer pre-stressing force. This study investigates the bond strengths of CFRP rods, CFRP strands, and steel strands following ISO 10406 standards. The research comprehensively explores the influence of cable type, cable surface roughness, and concrete strength on bond-slip behavior. Experimental results were augmented using a data augmentation method to enrich the dataset, which facilitated the development of a robust random forest (RF)-based prediction model for bond strength. The RF model achieved strong performance metrics, including a mean absolute percentage error (MAE) of 17.9 % and an R-value of 0.97, underscoring its efficacy in predicting bond strength. Notably, the model highlighted the significant impact of cable surface roughness on bond strength relative to other parameters studied based on the feature importance analysis. This study contributes to advancing the understanding of CFRP's applicability as a steel tendon replacement in prestressed concrete structures. The findings emphasize the importance of surface characteristics in optimizing bond strength, providing valuable insights for structural engineers and material scientists.

A bi‐level optimization model and improved algorithm for wind farm layout

AbstractWind farm can obtain the maximize profit by optimizing micro‐locations and cables. The factors that affect profit include the power output of wind turbines, cost and et al., where power output is affected by wake effect, cable cost is related to the length and type of collector cable. The profit is calculated on the premise that the costs and power loss of collector cable are determined. Obviously, there is a hierarchical relationship between the above problems. Therefore, a bi‐level optimization model with constraints is constructed in this paper, where the upper‐level objective function is the maximum profit, and the lower‐level objective functions are consists of minimum the cable cost and the power loss of collector cable; Moreover, an improved algorithm (IDEDA), based on differential evolution and Dijkstra, is used to optimize above model; Finally, simulation experiments are carried out for IDEDA and four algorithms for two different wind conditions, and the results show that IDEDA performs better compared to the other four algorithms in terms of profit and cable cost.

Short-term extreme response estimation methodology for marine umbilical cables with two configuration types

This study investigates the critical engineering problem of the short-term extreme responses of marine umbilical cables, which are essential components in offshore oil and gas operations. Umbilical cables play a pivotal role in connecting subsea systems to surface platforms, necessitating a safe design to withstand external loads. This study focused on two primary umbilical cable configuration types: deep-water catenary and shallow-water lazy wave. For each configuration type, 100 3-h dynamic numerical simulations were performed, with maximum values fitted by using the Gumbel distribution, and the most probable maximum (MPM) values were set as benchmark values. The average conditional exceedance rate (ACER) method and uncertainty-incorporated ACER method were applied to study the short-term extreme values of umbilical cable responses based on limited sample data. The predicted results have been compared with the MPM values, and the accuracy and uncertainty of different efficient extreme-value analysis methods are discussed. This study provides a comprehensive methodological framework for the reliability analysis and safety design of umbilical cables in marine engineering.

Comprehensive investigation of bond properties of CFRP cables with concrete and mortar

This study investigated the bond properties of carbon fiber reinforced polymer (CFRP) cables with concrete and mortar. Analyses focused on the bond-slip behavior considering various factors, such as CFRP cable types (e.g., CFRP rod and strand), surface treatments, fixed end materials (e.g., concrete and mortar). Remarkably, the material type and compressive strength at the fixed end were found to have no discernible impact on bond-slip behavior. Conversely, the type of CFRP cable and its surface treatment emerged as pivotal factors influencing bonding strength outcomes. Employing the modified Bertero-Popov-Eligehanusen (BPE) model, a comparative evaluation was performed between experimental results and theoretical estimation of bond-slip behavior. Furthermore, image processing analysis revealed a similar bonding strength of CFRP cables with both concrete and mortar. This similarity can be attributed to the sparser distribution of coarse aggregates around cables in concrete samples, implying that the cementitious phase primarily governed the bond properties, resulting in consistent bonding strengths across different fixed end materials. Overall, this study sheds light on the intricate interplay between CFRP cable types, surface treatments, and material compositions, ultimately contributing to a deeper understanding of bond properties and their implications for various structural applications.

Harmonic power flow under non-sinusoidal conditions

This article aims to analyze the electric field and the flow of electromagnetic energy in power cables with copper and aluminum cores, without considering the implicit physics of the coating that surrounds the conductor, which is generally composed of XLPE. Computational simulations were carried out with two models of alternating electrical current (AC) intensities, with a frequency of 60 HZ, electrical voltage of 1 kV, in a transient regime, with a phase difference of 120° and considering the lengths of the cables at a value of L = 30 m. Applying a Fourier series expansion to a sinusoidal electric current and expanding to the third term of the series, resulting in a new formulation of the electric current that was called modified electric current. The peculiarity of this research lies in the fact that, through the Fourier series expansion of conventional alternating current, a transformation to a modified current was observed, presenting behavior analogous to that of a Rectifying Diode. The improvements provided by this method include increased efficiency in the transmission of electrical energy, reduction of voltage drops, reduction of losses associated with the Joule-Lenz effect and extension of the useful life of the cable. The results demonstrated that, by modifying the electric current, the electric fields and Poynting vectors were calculated and approached the solutions of Maxwell's equation for conventional electric current, in both types of power cables. In addition, this approach has been observed to be particularly effective for power cables with a length of 30 m, and using the modified current in Maxwell's equations to compare the electric and Poynting fields with those calculated using conventional electric current. Therefore, the results obtained are satisfactory for both power cables.

Experimental study on the mechanical characteristics of NPR anchored rock under kilometer-deep buried high geostress conditions

In this paper, a biaxial compression experimental study of NPR (Negative Poisson's Ratio) and PR (Poisson's Ratio) anchored rock under different burial depth conditions was conducted around a new type of constant resistance large deformation anchor cable, also known as NPR anchor cable. A comparative analysis was performed on mechanical characteristics of the two types of anchored rock. Furthermore, a concept of static toughness for anchored rock was established to evaluate the comprehensive mechanical performance. The results indicate that with increasing confining pressure, the elastic modulus of both types of anchored rock exhibits a gradual increase. The peak strength and residual strength initially decrease and then increase. The NPR anchored rock has higher elastic modulus, peak strength, and residual strength compared to PR, with increases of 17.5%, 26%, and 25%, respectively. As the confining pressure increases, the fine and short shear cracks within the lateral surfaces of the two types of anchored rock transform into wider and longer cracks. The final integrity of the NPR anchored rock is demonstrably superior to that of the PR. Compared to PR, the cumulative energy, cumulative count, and energy value per unit count of the NPR anchored rock throughout the experiment are significantly lower values. A calculated analysis revealed that the static toughness of the NPR anchored rock is considerably greater than that of PR.

Investigation of Mixed-Mode Crack Quantification with Distributed Fiber Optic Sensors

The development of high-resolution distributed fiber optic sensing (DFOS) technologies, particularly optical frequency domain reflectometry (OFDR), has proven effective in measuring crack widths. However, most existing research assumes that the crack opening direction is perpendicular to the cable direction, with limited studies addressing mixed-mode cracks using distributed fiber optic sensors. This research aims to create a novel method for quantifying mixed-mode cracks using DFOS, combining experimental investigations and numerical simulations. A calibration rig was designed and fabricated to simulate mixed-mode crack conditions in a 2D plane, allowing for the reproduction of various crack opening scenarios. Multiple fiber optic cable types with distinct strain transfer mechanisms were used, crossing the artificial crack surface at varying angles. The mechanical behavior of fiber optic cables in mixed-mode crack situations was further examined through numerical simulations. Based on findings from both experimental and numerical studies, an algorithm was developed to determine crack width and crack opening direction using DFOS data. As mixed-mode cracks frequently occur in reinforced concrete structures under complex stress conditions, this research enhances the understanding of fiber optic sensor performance in realistic cracking situations and offers valuable insights for more precise damage assessment using DFOS.

Floating wind farm design using social and environmental constraints

This work proposes a wind farm design methodology, integrating several design variables from different design aspects into an optimization problem, such as turbine power, number of turbines, cable types, wind farm layout and site location. A mixed integer genetic algorithm is employed to combine discrete and continuous design variables to find the design with minimum Levelized Cost of Energy (LCoE). The wind farm LCoE is calculated using a wind farm model, which combines detailed cost functions for different cost elements and engineering wake models to estimate Annual Energy Production. The design is constrained not only by technical aspects such as total power, farm area, but also by environmental and social constraints. These include the wind farm visibility, which is a popular concern among the people living along the coast of nearby wind farms, and availability, implying the compliance with the designated exclusion zones. To demonstrate the sensitivity of design constraints, two floating wind farms are sited and optimized as a case study, using different visibility constraints. The developed design tool within this study aims to bridge the gap between wind farm developers and local authorities who are responsible for permitting and zoning of development areas.

Numerical Investigation on the Structural Behavior of a Short-Span Cable-Stayed Bridge with Steel and CFRP Hybrid Cables.

In this paper, a thorough investigation is presented on the static and dynamic behaviors of a short-span cable-stayed bridge (CSB) incorporating steel and carbon fiber reinforced polymer (CFRP) hybrid cables. The study focuses on the world's largest span and China's first highway, CFRP CSB. The performance of the CSB was compared using numerical simulations under four different cable patterns: steel cables, CFRP cables, and steel, and two types of hybrid cables with different structural arrangements. The results indicate that the use of the use of CFRP cables in the long cable region in the short-span CSB project investigated in this study offers improved performance in terms of stability, seismic response, and reduced displacements. In comparison to CFRP cables, hybrid cables have demonstrated a reduction of 12% in the maximum vertical displacement of the main girder. On the other hand, the hybrid cables result in reduced maximum internal forces and longitudinal and lateral displacements of the main girders and towers compared to steel cables. The difference in the arrangement of CFRP cables in the long cable region or short cable region is not obvious under dead loads, but significant differences still exist between the CFRP cable bridges in the short cable region and the long cable region in terms of live load effects, temperature effects, and dynamic characteristics.

Shape Control of Elastic Deformable Linear Objects for Robotic Cable Assembly

Currently, cables are manually installed in aircraft manufacturing scenarios. The utilization of robots in cable assemblies can enhance efficiency and ensure quality, presenting great promise for the future. However, the assembly process must control the shape of the cables, which is a significant challenge for robots. On the one hand, cables have high degrees of freedom in space, making accurate modeling of cable dynamics for robotic arm manipulation difficult; on the other hand, cable deformation has uncertainty, and the applied forces cause simultaneous deformation and motion, which is difficult to control. To address these problems, this study proposes a cable‐shape control method based on graph neural networks and online visual shape‐servoing. The method first approximates cable dynamics with a graph neural network. Then, in practice, the learnt model is used alongside visual‐based shape‐servoing to generate optimal robotic arm movements, controlling the cable to attain the desired shape. In the experiments, precise control of three different cable types is realized, and an example of a completed cable assembly is shown.

Experimental measurements of gamma-radiation effects on fiber-optic cables

This paper reports on our study of the effect of gamma-ray irradiation on two types of experimental fiber-optic cables. The first type of cable, CTFS, had a jelly-filling compound, whereas the second type, CTDS, was without the jelly. The cables contained three multi-mode (A, B, C) and five single-mode (D, E, F, G, H) optical fibers. The study was performed using two gamma-irradiation facilities with 60Co sources for slow long-term irradiation with the dose of 80.5 kGy at the low dose rate of 5.5 Gy/h and with the dose of 65.5 kGy at the higher dose irradiation rate of 0.94 kGy/h. After the irradiation with the dose of 80.5 kGy, the C fiber in the CTDS cable had the optical loss of 5.91 dB; 140 days after the gamma treatment at the wavelength of 1300 nm, it was 4.96 dB. The lowest optical losses for a single-mode fiber after irradiation with the dose of 65.5 kGy were found for the D fiber in the cable CTFS, namely 3.26 dB at 1490 nm and 3.49 dB at 1310 nm. In the fiber E in the CTDS cable, the optical loss was 3.62 dB at 1550 nm. In the fiber F in the CTDS cable, it was 3.86 dB at 1310 nm.

Shaking table test for seismic performance of rock slope reinforced by C&S–R anchor cables

To investigate the seismic reinforcement performance of compression and self-recovery (C&S–R) anchor cables, a series of shaking table comparison tests were conducted on rock slopes reinforced by two types of anchor cables: C&S–R anchor cables and conventional anchor cables, under different seismic intensities. During the tests, multiple accelerometers, displacement meters and strain gauges were synchronously arranged to monitor the strain of anchor cables and the dynamic response of the anchored slopes. The test results reveal that C&S–R anchor cables had better seismic performance. Compared to conventional anchor cables, C&S–R anchor cables had a peak axial strain reduction of approximately 23.0% and an increase in seismic intensity of 0.1g–0.2g. The final natural frequencies of the slope reinforced by C&S–R anchor cables and that of the slope reinforced by conventional anchor cables were 31.25 Hz and 26.1 Hz, respectively, confirming that C&S–R anchor cables reduce the internal damage of the anchored slopes during earthquakes. The results provide guidance and basis for the seismic optimization design of anchored slopes.

A Method for Assessing the Degradation of PVC-Insulated Low-Voltage Distribution Cables Exposed to Short-Term Cyclic Aging

The distribution grid comprises cables with diverse constructions. The insulating material used in low-voltage (LV) distribution cables is predominantly PVC. Furthermore, the presence of cables with different structures in the grid poses challenges in detecting the aging of the cable network. Finding a universal and dependable condition-monitoring technique that can be applied to various types of cables is indeed a challenge. The diverse construction and materials used in different cables make it difficult to identify a single monitoring approach that can effectively assess the condition of all cables. To address this issue, this study aims to compare the thermal aging behavior of different LV distribution cables with various structures, i.e., one cable contains a PVC belting layer, while the other contains filler material. The growing adoption of distributed generation sources, electric vehicles, and new consumer appliances in low-voltage distribution grids can lead to short, repetitive overloads on the low-voltage cable network. Hence, these cable samples were exposed to short-term cyclic accelerated aging in the climate chamber at 110 °C. The cable’s overall behavior under thermal stress was evaluated through frequency and time domain electrical measurements (including tan δ and extended voltage response) and a mechanical measurement (Shore D). The tan δ was measured in the frequency range of 20 Hz–500 kHz by using the Wayne-Kerr impedance analyzer. The extended voltage response measurement was conducted using a C# application developed in-house specifically for laboratory measurements in the .NET environment. The study observed a strong correlation between the different measurement methods used, indicating that electrical methods have the potential to be adopted as a non-destructive condition-monitoring technique.

Investigation of mechanical behaviors of spoke-wheel cable structures through experimental and numerical analysis driven by digital-twin

Ascertaining the mechanical behaviors of large-scale space structures (e.g. spoke-wheel cable structure) is essential for guaranteeing their structural safety. This study proposed a digital-twin (DT)-based method for analyzing the mechanical behaviors of spoke-wheel cable structures. A spoke-wheel cable structure with a span of 6 m was used as a case study to validate the proposed method. The structural behaviors, such as cable forces and structural displacements under five loading conditions (i.e. dead load and dead load plus 3/10, 5/10, 8/10 or full-areal live load), were investigated experimentally and numerically. A comparative analysis was conducted to compare the results using the proposed method with the traditional method. Results show that the proposed DT method could help to update geometric details and boundary conditions of the twin model for ensuring effective numerical analysis. Moreover, the changing trends of general force for the same type of cables were basically the same under different loading conditions. Besides, the forces of upper spoke cables and inner-ring decreased under the action of live load, whereas the forces of lower spoke cables and inner-ring increased. The displacement directions of loaded and unloaded nodes were downward and upward, respectively, when subjected to uneven live loads. In addition, the vertical displacements of the outer nodes were greater than thoseof the inner ones. Furthermore, the cable forces and displacements of the structure changed more obviously under the action of asymmetric load. The established high-fidelity DT model could support effective numerical analysis of mechanical behaviors of large-scale space structures.

Intelligent Traffic Engineering for 6G Heterogeneous Transport Networks

Novel architectures incorporating transport networks and artificial intelligence (AI) are currently being developed for beyond 5G and 6G technologies. Given that the interfacing mobile and transport network nodes deliver high transactional packet volume in downlink and uplink streams, 6G networks envision adopting diverse transport networks, including non-terrestrial types of transport networks such as the satellite network, High-Altitude Platform Systems (HAPS), and DOCSIS cable TV. Hence, there is a need to match the traffic to the transport network. This paper focuses on such a matching problem and defines a method that leverages machine learning and mixed-integer linear programming. Consequently, the proposed scheme in this paper is to develop a traffic steering capability based on types of transport networks, namely, optical, satellite, and DOCSIS cable. Novel findings demonstrate a more than 90% accuracy of steered traffic to respective types of transport networks for dedicated transport network resources.