Search

Automating the assembly and handling of deformable linear objects requires their robust detection. This paper introduces a new evaluation metric for the results from instance segmentation. The metric enables estimating the proportion of valid grasp poses and graspable objects for specifc gripper models. The results demonstrate that masks with similar scores in area-based metrics can have different grasp pose validity outcomes. In addition, it is indicated that when handling deformable linear objects with a vacuum gripper, it is possible to achieve a grasp precision and grasp recall of about 90 %. [ABSTRACT FROM AUTHOR]

In industrial production, the handling and mating of electrical connectors are carried out manually in most applications. Therefore, automation offers potential for improvement. Designing a suitable gripper system is a crucial step. However, this is currently only possible exploratively, requiring empirical knowledge and time. This paper presents a concept for automating the design process of gripper systems for electrical connectors. For this purpose, physics simulation for the mechanical impact of cables and grasp planning for the complex geometry of electrical connectors are considered simultaneously. The concept aims to automatically derive CAD data for gripper jaws that are suitable for electrical connectors. [ABSTRACT FROM AUTHOR]

Carbon-fibre-reinforced polymer (CFRP) cables have attracted the attention of people as a corrosion-free substitution of steel cables serving in aggressive environments. The production of CFRP cables generally refers to that of steel cables at the present, but as CFRP cables do not have corrosion risk, the step of greasing the external surface of the tendon bundle of steel cables is sometimes omitted. This results in various bond states between the outermost protective sheath and the tendon bundle, which affect the impact load transfer and thereby affecting the impact behaviour of the CFRP cable but has never been properly considered when developing the protective sheaths. To understand the effect of the bond state on the impact behaviour of CFRP cables, and to find the optimal type of protective sheaths, the present study designed three types of protective sheaths (Type 1, free-sliding sheaths; Type 2, fixed sheaths; and Type 3, semi-fixed sheaths) and simulated them with achievable materials. Drop-weight impact tests were carried out on 2-meter-long CFRP cables with protective sheaths. The test results showed that the semi-fixed type of sheaths performed the best among all three types in delaying the fracture, improving the achievable maximum impact force and tension, and enhancing the energy dissipation capacity of the CFRP cable. Therefore, the semi-fixed type of sheaths is the recommended type for CFRP cables. • Three types of bond states between the protective sheath and the tendon bundle of a CFRP cable were identified. • Free sliding, fixed and semi-fixed types of protective sheaths for CFRP cables were designed. • Drop-weight impact tests were carried out on 2 m-long CFRP cables with protective sheaths. • The semi-fixed type of protective sheaths is the recommended type for CFRP cables against impact loading. [ABSTRACT FROM AUTHOR]

To address both illumination issues and the common vortex-induced vibration (VIV) of bridge cables, a perforated shroud light device is proposed. The effect of the different porosities (20%, 35%, 42%, and 55%) on VIV of the rigid segmented shroud cable models is studied first by wind tunnel tests. It reveals that shrouds with porosities of 20% and 35% could reduce the VIV amplitude of the smooth cables by 26% and 46%, respectively. However, shrouds with porosities of 42% and 55% tend to increase the complexity and risk associated with VIV. Vibration measurements on flexible should cable with 20% porosity were conducted for both vertical and inclined models with an inclination of 35° and yaw angles of 0°, 30° and 60°. Shrouds with a porosity of 20% exhibit similar effects on vertical flexible cables as on horizontal rigid cables, in both cases mitigating VIV. The impact on the inclined flexible cables depends on the yaw angle. At the yaw angle of 0°, the shroud effectively mitigates VIV in flexible cables. However, at yaw angles of 30° and 60°, the same porosity level shroud exacerbates the risk of VIV in the inclined flexible cable. This may be due to the enhanced wind velocity along the cable axial direction and decreased penetrating flow rate through the shroud as the wind yaw angle increases. Overall, it was found that a shroud with a porosity of 20%–35% performed the best and was recommended for applications on cables with no inclination and inclined cable at yaw angle β = 0°. • Perforated shroud light devices are proposed to address both illumination and the vortex-induced vibration of bridge cables. • Wind tunnel tests were carried out on rigid and flexible models, respectively. • It was found that a shroud with a porosity of 20%–35% performed the best. [ABSTRACT FROM AUTHOR]

Data on bacterial adhesion to cerclage cables are sparse. We aimed to compare 5 cerclage products for methicillin-resistant Staphylococcus aureus (MRSA) adhesion to determine the claim: Are nonmetallic polymer cables more resistant to bacterial adhesion than common metallic wires and cables? The following 5 cerclage products were compared: (1) monofilament stainless steel (SS) wires; (2) multifilament SS cables; (3) multifilament cobalt chrome cables; (4) multifilament Vitallium alloy (cobalt-chrome-molybdenum [Co-Cr-Mo]) cables; and (5) multifilament nonmetallic polymer cables. Each was cut into 2 cm lengths and placed into 12-well plates. Of the wells, 5 were wire or cables in trypticase soy broth with MRSA, with the remaining wells being appropriate controls incubated for 24 hours at 37° C and 5% CO 2 with shaking. Wires and cables were prepared and randomly imaged via scanning electron microscopy, with bacterial counts performed on 3 images of 3 different wires or cables per study group. The scanning electron microscopy technician and counting investigator were blinded. Additionally, SS wire and polymer cables were analyzed by microcalorimetry for metabolic activity and bacterial load. Bacterial attachment differed significantly between study groups in the middle section (P =.0003). Post hoc comparison showed no difference between groups individually (all P >.05) apart from polymer cables (median 551 bacteria) having significantly increased attached bacteria compared to the Vitallium alloy cable (157, P =.0004), SS cable (101, P =.0004), and SS wire (211, P =.0004). There was no difference between polymer and cobalt chrome cables (133, P =.056). Microcalorimetry supported these results, as polymer cables had a shorter time to max heat flow (6.2 versus 7.5 hours, P =.006), increased max heat flow (117 versus 64 uW, P =.045), and increased colony-forming units, indicating an increased bacterial load compared to SS wires. This in vitro study demonstrated that polymer cables have increased MRSA adhesion compared to common metallic wires and cables. Future studies are necessary to confirm the translation of increased bacterial adherence on polymer cables to increased rates of orthopaedic infections. [ABSTRACT FROM AUTHOR]

The remaining useful life (RUL) prediction is key for ensuring the stability of transmission power systems. However, there is no sufficient actual life-cycle, and no mature physics-of-failure model of the power transmission facilities, which make it difficult to predict RUL. In this paper, we propose an AI-based transmission line RUL prediction method which incorporates the measured operating conditions of each line. The proposed method sets the basic linear asset unit as one cable segment and joint boxes on both sides. A feature extraction and piecewise-based RUL model was designed using asset data from 1,458 actual transmission lines accumulated by measuring unit over a period of 44 years. Consequently, the RULs which depend on load operating conditions of target assets can be successfully predicted using CNN-LSTM. In addition, a data augmentation algorithm based on time-series generative adversarial networks was developed to address the issue of imbalanced failure data and further improve the accuracy of RUL prediction. The performance of the proposed RUL estimation method is further verified using real-world data. The proposed method shows an improvement in fault-healthy classification accuracy by 35.72%, 21.43%, and 7.14% compared to existing feature extraction methods, including deep neural networks (DNN), convolutional neural networks (CNN), and autoencoder (AE), respectively. Additionally, when compared to representative deep learning models for RUL estimation, it achieves the best performance with RMSE and Score of 0.074 and 0.066, respectively. Moreover, the proposed method is capable of accurately estimating RUL even for equipment in the early failure period, where the actual operating time is short. • A novel AI framework for estimating the RUL of transmission power facilities. • We address real industry data imbalance using TimeGAN while modeling a piecewise-based RUL curve. • Using RF regression, we can extract failure class probabilities, enabling the generation of missing features in asset data. • The proposed model is proposed to estimate the RUL of transmission power facilities in South Korea. [ABSTRACT FROM AUTHOR]

• The inductive properties of different cables, including communication and electrical cables, coupled into the double toroidal magnetic field are summarized in the time-domain waveforms and accumulated energy. • Influence of the various type and shielding methods of communication cables on induced surges is revealed. • Different number of cores and different shielding methods of cables are investigated for their ability to protect against lightning surges. • The simulation results of the double toroidal magnetic field are basically the same as the experimental results, which can be used as subsequent experimental calculations, both for different lightning surges and different experimental environments. The coupling of lightning electromagnetic pulse (LEMP) on cables can generate disruptive surge current and voltage, which may cause damage to devices or systems connected with cables. In this paper, a double toroidal magnetic field, through injection of an 8/20 μ s lightning current into a double toroidal coil, is generated to induce indirect effects on nine communication/electrical cables. The impacts of different types and shielding methods of communication cables on induced surge current are evaluated, and the results show that twisted-pair cables with shielding layer have the best shielding effectiveness, with the ability to absorb more energy on the communication cables from LEMP. In addition, the study's findings demonstrate that the induction properties of cables are independent of the number of cores, but related to the shielding layer of cables. Meanwhile, simulation analysis in CST Studio Suite is carried out here, and results are basically similar to experimental results, with the difference attributed to the ignorance of some losses in the simulation environment. Finally, the magnetic field strength at each point of the LEMP is simulated, with some engineering proposals for the actual and simulated experiments. [ABSTRACT FROM AUTHOR]

Background: Different stand-alone cerclage configurations and their optimal twisting techniques have been investigated over the years. This study tests for the stabilizing effect of different supplemental cerclage materials in combination with locked plating of distal tibia fractures.Methods: Locking plate fixation of a distal tibial spiral fracture was tested as stand-alone and with supplemental cerclage materials (one cable, two cables, wire, fiber tape). Construct stiffness and fracture gap movements were investigated under quasi-static and dynamic loads and compared to the stand-alone locking plate.Results: With each of the tested cerclages, stiffness was significantly higher than for a solitary plate osteosynthesis. Most reduction in fracture gap movement was achieved by cable cerclages, followed by double-looped wire and double-looped fiber tape cerclages. Under dynamic loading an additional cable cerclage reduces excessive gap movement.Conclusion: Compared to solitary plate osteosynthesis all supplemental cerclage materials were generally superior with reduced fracture gap movements whereas cable cerclages showing the greatest stabilizing effect. [ABSTRACT FROM AUTHOR]

Carbon fiber-reinforced polymer (CFRP) cables are an attractive material for bridge cables due to their light weight, high strength, and corrosion resistance properties. However, research on their long-term creep performance is limited. In this study, long-term creep tests were conducted on self-anchored CFRP cables under various stress levels to evaluate their creep performance and residual mechanical properties. Based on experimental data, million-hour creep coefficients and relaxation coefficients were predicted. The results indicated that the self-anchored CFRP cable system had a million-hour creep coefficient ranging from 6.1 % to 7.9 % at stress levels from 0.3 f u to 0.7 f u (where f u represents the characteristic tensile strength). Additionally, maintaining low and medium stress levels for 1000 h improved the tensile strength and stability of the CFRP cables. The self-anchored CFRP system was also able to provide effective anchorage even after continuous loading. By comparing with the steel cable data in the literature, the self-anchored CFRP system exhibited smaller creep and relaxation, as well as superior residual tensile properties. These findings suggested that the self-anchored CFRP cable exhibited favorable long-term reliability, and finally self-anchored CFRP cables were successfully applied to a bridge in the campus of Tsinghua University. [ABSTRACT FROM AUTHOR]

• The simulation model of cable in duct bank with mixed filler was built. • The improved thermal model of cable in duct bank with mixed filler was proposed. • The accuracy of the improved method was verified by the real cable test. • The cable ampacity improvements of using different mixed fillers were discussed. • The basis for determining the performance of mixed filler was provided. Duct laying is a common cable laying way for the case of not meeting excavation conditions. However, due to the slow air flow rate in the duct, the cable section laying the duct becomes one ampacity bottleneck. Backfilling the duct with the mixed filler of high thermal conductivity material and phase change material is an effective method to solve the problem. In this paper, the simulation models of cable in ducts with backfilling the mixed filler were used to analysis the effect of relative position of cable and duct on temperature distribution and guide the thermal modeling of external environment. Then, the thermal model of cable in duct was conducted and the layered method was adopted to optimize the model. The real cable experiment was designed to verify the accuracy of proposed model. The improvement effect of mixed filler with different thermal conductivity and phase transition region on the cable ampacity were discussed by using the proposed model. The investigations in this paper show that the use of mixed filler material can have a great contribution to ensure the safe operation of cable in duct. [ABSTRACT FROM AUTHOR]

• Macro finite element implementation and validation. Combination of FEM and DEM. • Cable and sliding mass under large displacement connected to beam finite elements. • Validation and application on cable based structures in dynamic conditions. This paper presents the formulation of a finite element enclosing a specific internal mechanical equilibrium in order to model cable-based structures in dynamics conditions. It is based on the concept of macro finite element which allows embedding complex mechanical systems solved inside the element boundaries. A significant advantage is to allow an easy implementation within classical commercial codes. The proposed macro finite element describes a cable interacting with a sliding object assimilated to a punctual mass where friction can be accounted for. The dynamic response is described by a model developed within the framework of the DEM (Discrete Element Method) where geometrical nonlinearity (large displacements) is considered. A model combining the proposed macro finite element and a classical linear truss finite element is presented in order to validate its implementation. Finally, illustrative examples are presented. First, a cable yarning system is considered. The effect of friction and of the bending stiffness of the posts on the overall kinematics and force within the system are explored. Then the vulnerability of a cable-stayed bridge to earthquake is explored accounting for guy ropes failure. [ABSTRACT FROM AUTHOR]

This paper presents an efficient yet practical approach for the automatic modal identification of structures based on their free vibration response. The proposed approach relies on the Empirical Fourier Decomposition (EFD) technique. It implements a new procedure to recognize automatically the number of modal components to be extracted from noisy data in such a way to prevent both mode-mixing and mode-splitting effects. A suitable strategy is adopted to improve the segmentation of the frequency spectrum of the free vibration response, so as to identify accurately the bounds of the frequency spectrum partition corresponding to each modal component. The related modal damping ratios are estimated by means of a robust area-based approach in order to mitigate the noise-induced disturbances whereas a time-domain method based on the phase shift of the free vibration response peaks is employed to identify the mode shapes. The proposed approach is first validated through the analysis of synthetic signals that embed closely spaced components and a lowly excited vibration mode. Finally, the proposed approach is applied to two real bridges. The first case-study deals with the identification of modal frequencies and damping ratios of the cables of a stay-cabled bridge. The second case-study involves the modal identification of a steel railway bridge deck that exhibits two closely spaced vibration modes. The outcomes obtained using the proposed approach based on EFD technique are compared with the results obtained by means of the Variational Mode Decomposition (VMD) technique as well as with those computed through classical operational modal analysis techniques. The consistent estimates produced by means of the proposed approach demonstrate its accuracy and robustness. • Empirical Fourier decomposition with fully automatic implementation procedure. • The procedure prevents both mode-mixing and mode-splitting effects. • Smoothing-based improved segmentation of frequency spectrum for noisy signals. • Robust area-based approach integrated in the procedure to identify damping ratios. • Identification of cables in cable-stayed bridges and of steel railway bridge deck. [ABSTRACT FROM AUTHOR]

This study investigates the behaviour of a fire propagating over a long length of electrical cables, in order to assess the maximum burning length and the associated heat release rate of the travelling fire. It is part of the research work conducted in the framework of the OECD/NEA PRISME 3 project for a better assessment of fire propagation over cable trays in nuclear installations. The fire scenario consists of a set of 3 horizontal cable trays 6 m long, positioned in the corridor of a mechanically ventilated large-scale compartment. The parameters of the study are the nature of the cables (thermoset or thermoplastic types) and the distance of the cable trays from the ceiling. The determination of the fire heat release rate (HRR), the total burning length, the velocity of the flame front, the heat release rate per unit area (HHRPUA) and the effective heat of combustion (EHC) of the cable fires are given. For the configuration studied (3 cable trays and a given load), fire HRRs of 160 kW and 520 kW corresponding to burning lengths of 2 m and 3 m and corresponding to velocities of 0.4 mm/s and 0.9 mm/s are obtained for thermoset cables. For thermoplastic type cables (made of polyvinyl chloride), a power of 730 kW corresponding to a burning length of 3.5 m and corresponding to a velocity of 1.9 mm/s is reported. The order of magnitude for HRRPUA and EHC were respectively ranged between 50 kW/m2 and 150 kW/m2 and 20 MJ/kg and 25 MJ/kg for the two cable types. • Large scale fire tests of long cable trays. • Flame spread velocity of travelling fire over long cable length. • Effect of distance from the ceiling and cable type. [ABSTRACT FROM AUTHOR]

• Algorithm for fast calculation of energization overvoltage of hybrid overhead line-cable transmission lines is proposed. • Algorithm is based on full frequency-dependent parameters and modal theory. • Relative errors of the obtained results are less than 0.261 %. • Time consumed by proposed method is only about 32.7 % – 58.6 % of PSCAD/EMTDC. This paper addresses the challenges associated with the time-consuming and complex nature of using electromagnetic transient (EMT) simulation software, such as PSCAD/EMTDC, for calculating transient overvoltages in complex power grids. To overcome these challenges, we propose a novel algorithm for fast calculation of energization overvoltages in hybrid overhead and cable transmission lines. The proposed algorithm begins by calculating the frequency-dependent parameters of the transmission lines in the full frequency domain. These parameters are then decoupled using phase-mode transformation. Subsequently, the algorithm derives the boundary conditions of the transmission line based on its topology, leading to corresponding complex frequency-domain voltage expressions. To obtain the calculation results of energization overvoltages along the hybrid transmission lines, the algorithm applies mode-phase transformation and an improved numerical inverse Laplace transform (NILT). To verify the accuracy and speed of the proposed algorithm, it is applied to a 330 kV hybrid overhead line and cable transmission system with a length of 56.8 km. The results demonstrate that the proposed algorithm achieves a maximum relative error of less than 0.261 % compared to the frequency-dependent phase model (FDPM) used in PSCAD. Additionally, the calculation time of the proposed algorithm is shown to be only 32.654 % – 58.649 % of the FDPM's calculation time. [ABSTRACT FROM AUTHOR]

Highlights • Superelastic shape memory alloy (SMA) cables are comprehensively studied. • Thermal-mechanical characterisations of the SMA material are carried out. • A series of SMA cable specimens are tested under various cyclic loading protocols. • A simple yet effective numerical modelling method is proposed for SMA cables. • A prototype bridge employing SMA cables as restrainers is designed and analysed. Abstract This paper reports a comprehensive study on the mechanical behavior, annealing (heat treatment) scheme, hysteretic modelling strategy, and potential seismic application of superelastic shape memory alloy (SMA) cables. The study commenced with the thermal-mechanical characterization of monofilament SMA wires, and in particular, the influence of annealing scheme on the mechanical and phase transformation characteristics of the material was revealed. A series of 7 × 7 SMA cable specimens were subsequently tested at room temperature under various cyclic loading protocols. It is observed, among other findings, that the SMA cables are able to reasonably "scale up" the satisfactory properties of the SMA wires, and the mechanical behavior of the SMA cables may be improved by annealing. Moderate annealing temperature and duration (i.e., 350–400 °C for 15 min) can generally increase the stiffness, energy dissipation, and form setting ability of the SMA cables considered in this study, whereas an overly high annealing temperature tends to compromise these characteristics. Following the experimental study, an effective numerical modelling approach is proposed which reliably captures the basic mechanical behavior of the SMA cables. A model bridge, where SMA cables are adopted as restrainers, is finally designed and analyzed to demonstrate the efficiency of the SMA components for seismic damage mitigation. The analysis result shows that the SMA-cable restrainers can effectively control the peak and residual displacements of the bridge girder, and make the bridge more resilient. [ABSTRACT FROM AUTHOR]

Abstract The automobile industry is demanding new car components to reduce vehicle emissions and increase efficiency. Lightweighting strategies are the most followed by manufacturers to reduce the weight and fuel consumption of vehicles. In this study, an innovative signal cable solution for the wire harnesses of vehicle is analysed through a life cycle assessment (LCA) and benchmarked with the replaced cable. The innovative cable is made up of a copper-tin alloy, while the traditional cable is made of copper. Both products are twisted and insulated with plasticised polyvinyl chloride. The new cable reduces the weight and volume by 53% and 41%, respectively, compared to the traditional cable. The production of raw and ancillary materials was found to be the main impact contributor, mainly due to the production of the conductive and insulation materials. Similarly, electricity consumption was the main impact carrier for the manufacturing stage. The environmental burdens obtained for the innovative cable were, on average, 54% lower than those obtained for the replaced one. Additionally, the potential marginal gains for the automobile industry were evaluated in terms of fuel consumption reduction, which is linked to vehicle weight, and the derived emissions, obtaining a significant exhaust emission reduction of 160 kg CO 2 eq when compared to the baseline scenario. Finally, the LCA of these products was decisively influenced by the consumption of raw materials and, therefore, the reduction of the thickness of the wire makes the cables considerably more sustainable from an environmental point of view. Highlights • Innovative cable reduces the amount of materials consumed and the cable weight • The reduction of the cable weight results in lower environmental impacts • Raw and ancillary material production is the main impact carrier • The lightweighting cable leads to a reduction in vehicle fuel consumption [ABSTRACT FROM AUTHOR]

[Display omitted] • System's functioning is based on measuring the length of cables stretched along the sprayer boom. • Displacements of the ends of the extreme beam segments are recorded in two planes. • Data in relation to the time axis allow to determine instantaneous speeds and accelerations. • Described system can also be used in field crop conditions. This study proposes an innovative system for measuring the displacement of a sprayer boom's tips and calculating their velocity and acceleration in the horizontal and the vertical plane. The system measures the length of measuring cables which are attached at the end of a sprayer boom's tips. Two supports are mounted in the central part of the sprayer boom. Absolute rotary encoders with measuring reels and tension springs are attached to the supports, which enables the system to determine changes in the position of boom arms in two perpendicular directions. The signals generated by each encoder are transmitted to a computer by a rapid data acquisition device, and they are transposed to the indicated parameters. The designed system can be used to measure sprayer boom displacement both in the field and in laboratory experimental tracks. [ABSTRACT FROM AUTHOR]

• Expand the application of singularity functions for cable configuration. • Provide the mathematical derivation defining the cable deflection and forces when subject to point loads. • Define the procedure to employ the developed method for determining cable configuration during varied construction stages. • Provide an example of determining cable configuration by using developed method when main span cable is subject to point loads from suspenders. This paper presents a solution procedure for cable configurations, such as the ones used for suspension and cable stayed bridges. It employs a semi analytical method with direct integration of singularity functions. The procedure is rigorous and more efficient than other solution techniques for this class of structures. It can include any number of discontinuous and continuous loads and can take into account the initial configuration of the cable. Because of its efficiency the solution process compared to other solution methods such as finite element analysis is suitable for parametric studies that are needed during the design and construction processes. The procedure may also be used for developing a macro element of cable and its suspenders for use in an efficient finite element solution. [ABSTRACT FROM AUTHOR]

This paper presents a new modelling approach based on idempotent decomposition of the nodal admittance matrix for representation of cables and overhead lines (OHL). By subjecting the idempotent matrices rather than the nodal admittance matrix to rational fitting, the poor observability of the smallest eigenvalues in the lower frequency range is overcome. Unlike the well-known method of characteristics (MoC), this alternative representation yields a so general fully-coupled admittance matrix suitable to tackle scenarios encompassing short and long lengths. Besides retaining the frequency dependence of parameters, the proposed phase-domain model showed to be accurate and suitable to circumvent the requirement of small time-steps. • New approach for line/cable modelling exploiting the idempotent decomposition of the nodal admittance matrix. • Linear transformation to overcome some issues encountered in the direct fitting of the nodal admittance matrix. • Time-domain results validated with the Numerical Laplace Transform algorithm. • Alternative to circumvent the presence of short and long line/cable lengths. [ABSTRACT FROM AUTHOR]

Faulty feeder selection is a challenging task for distribution system operator due to the low earth fault current magnitudes in compensated networks. However, extensive cable usage, especially in metropolitan cities, causes unintentional resonance in the network earthed through inductance or grounding transformer. The unintentionally resonated networks are not designed like intentionally compensated networks where faulty feeder should be isolated in a predetermined time. There are transient zero sequence current based methods, particularly synthesized for compensated networks to identify faulty feeders. However, zero sequence-based faulty feeder selection methods have drawbacks in the presence of underground cables. Further, transient zero sequence current is prone to many parameters such as capacitive imbalance and fault resistance. In this study, a transient negative sequence current based faulty feeder selection method is proposed. The effectiveness of the proposed method is demonstrated in a simulated 151-node distribution network. EMTP simulations are carried out by considering different fault inception times, fault resistance and capacitive imbalance of the system. Results show that negative sequence current offers selective faulty feeder selection and no false trip is observed in a representative unintentionally resonating distribution network. • Capacitive current of underground cables may cause unintentional resonance in reactance grounded distribution networks. • Classical zero sequence protection components may not provide selective faulty feeder selection for unintentionally resonated networks. • Faulty feeder selection and false tripping problem in unintentionally resonated network is demonstrated on the 151-nodes distribution network. • Preventing false trips and providing selective earth fault protection, based on transient negative sequence current is proposed. • The effectiveness of the proposed method is shown in a simulated 151-nodes distribution network. [ABSTRACT FROM AUTHOR]

To establish a rigorous mathematical foundation for a recently developed tension determination method incorporating the mode shape functions, the frequency equations and mode shape functions for the vibrating cables with various types of boundary conditions are first derived in this research. According to these analytical expressions in terms of dimensionless parameters, it is confirmed that the mode shape functions associated with complicated boundary conditions are all dominantly contributed by the sinusoidal components to suggest a more convenient option than the intertwined frequency equations. Based on this discovery, the cable tension can be generally decided with an explicit formula similar to that for the case with hinged boundary constraints at both ends. The effective vibration length for each selected mode in the formula, however, needs to be pre-determined by fitting the corresponding sinusoidal function with the mode shape ratios identified from multiple synchronized measurements. Parametric study is also conducted on the derived mode shapes to systematically investigate the interference effect of the hyperbolic component near the boundaries and provide valuable guidelines for the sensor deployment in engineering applications. Finally, the performance of the developed methodology in the cases with more involved boundary constraints is certified with demonstrative numerical examples and laboratory experiments. [ABSTRACT FROM AUTHOR]

Numerical calculations of mechanical behavior in multi-filamentary Ag-alloy sheathed Bi-2212 superconducting round wires and cables are presented in this paper. Bi-2212 composite wires possess excellent current carrying capabilities even in magnetic field. The strain may lead to the degradation of critical current density. And the filament fracture caused by strain is a key issue to the application of superconductor. Due to the complex nonlinear electromagnetic characteristics of superconductor, we use the variational formulation based on the field-dependent critical state model to calculate the distributions of current and magnetic field in Bi-2212 composite superconducting wires and cables. The finite element method (FEM) is employed in the calculation of mechanical behavior. We have developed a numerical method by combining the variational formulation and FEM to calculate the two-dimensional electro-mechanical problem. The strain and stress distribution in infinity long Bi-2212 single wire, two wires, 6-around-1 cable and Rutherford cable carrying transport current in external magnetic field are calculated. The possible damage position in wires and cables is discussed. [ABSTRACT FROM AUTHOR]

Cable stress relaxation causes tension loss at high stress in high-strength structural cables, thereby influencing the stiffness and strength of cable-supported or tension structures. Previous studies have mainly focused on steel wires (SWs) and spiral strands; however, several new types of structural cable, such as semi-parallel wire strands (SPWS), Galfan spiral strands (GSSs), and steel tie rods, have emerged and have been widely applied in recent decades. The axial force during normal service state occasionally reaches 55% of the ultimate tensile strength. Relaxation data on structural cables are rare and are urgently required for structural design and lifetime safety evaluation. Therefore, experimental studies on five types of structural cable were conducted, in which the initial stress levels were 70%, 55%, and 40% of the ultimate tensile strength. Three different working ambient temperatures of 15 ± 2 °C, 20 ± 2 °C, and 25 ± 2 °C were considered. Special onsite anchoring methods and anchorage devices were established and proven effective. Results showed that logarithmic expression could well express the relationship between relaxation rate and time duration. The relaxation rates of SPWSs were larger than those of SWs. GSSs had considerably larger relaxation rates than other cable types due to their material properties and special twist characteristic. The relaxation rates of all types of cable increased with the initial stress and temperature. The recommended values for the 50-year relaxation rates for different structural cables were predicted and calculated. [ABSTRACT FROM AUTHOR]

Based on a mass-point model, the cable dynamics of a space elevator during a climber's travel motion are examined. The cable response during a single operation of one ascending or descending climber is analyzed first, and then, based on the results, the cable dynamics for simultaneous operation of an ascending and a descending climber are evaluated. For the single operation, bending is significant when the climber is traveling near the Earth's surface. The cable also inclines with periodic oscillation as a result of a Coriolis force corresponding to the climber velocity. However, simultaneous operation of ascending and descending climbers can suppress the inclination of the cable by almost a factor of ten. In simultaneous operation, compared to single operation, a descending climber has a smaller amplitude of libration angle and less cable bending, while an ascending climber has a smaller amplitude when the climber is traveling at a higher altitude with climber velocities of 200 km/h and 400 km/h. The phase of the oscillation of the overall cable is found to be close to that of the descending climber. Cable bending is suppressed for any examined climber velocity, but the dependency of this suppression of displacement on climber velocity is not found. In summary, simultaneous operation can surely suppress the inclination of the cable via the cancellation of Coriolis forces by the two climbers. [ABSTRACT FROM AUTHOR]

This study is focused on the radiooxidative degradation of polymeric insulation of electric cables used in Nuclear Power Plants (NPPs). In order to investigate the degradation mechanisms of the insulation, model composites with ATH (Aluminium TriHydrate) filler and blends (without filler) based on a cross-linked mixture of EVA (Ethylene Vinyl Acetate) and EPDM (Ethylene Propylene Diene Monomer) were submitted to gamma-rays. In normal operating conditions of a NPP, the dose rate which electric cables are exposed to is around 0.1 Gy h −1 . In this work, artificial accelerated ageing test process has been applied at a relatively low dose rate of 7 Gy h −1 . Gamma-irradiations at higher dose rates typically used to accelerate the ageing, in the range 0.2–1 kGy h −1 , were also carried out. The first part of the study is focused on irradiations performed at relatively low dose rate and is devoted to the highlighting of the radiooxidative degradation mechanisms of EVA/EPDM blend with and without ATH filler. Correlations between the evolutions of the chemical, morphological and mechanical/electrical properties of the materials occurring after the ageing process are presented. It is shown that the degradation process is governed by radical oxidation mechanism involving chain scissions leading to the formation of carboxylic acids as end-groups. One of the main effects of the ATH filler is the progressive loss of the mechanical properties of the composite upon radiooxidation whereas they are maintained in the case of the unfilled sample. Despite the oxidation of the polymer, no change in the electrical properties of the blend and of the composite could be observed. The second part of the study focuses on the dose rate effect. It is shown that one of the main consequences of an increase of the dose rate from 7 Gy h −1 to 0.2–1 kGy h −1 is a reduction of the chain scission process yield by a factor of about 20. Therefore, an important and consistent finding is that there are some limits that must not be exceeded in terms of dose rate to ensure a global satisfactorily representativeness of the accelerated ageing process. [ABSTRACT FROM AUTHOR]

• An improved technique for the calculation parameters of lines/cables is proposed. • Proximity effects, earth return, and skin effect are accurately modeled. • Increased modeling flexibility is given with the new tool, such as multilayer soil and combined underground/aerial lines. • Theoretical review and explanations on the reunited techniques is presented. • Demonstrations on transient applications are provided. This paper presents a new tool for the computation of per-unit-length parameters for transmission line and cable models used for simulating electromagnetic transients (EMT). The proposed methodology is based on the MoM-SO theory and state-of-the-art formulations for the computation of the series impedance and shunt admittance parameters. The new tool has major advantages compared to traditional approaches available in EMT-type software. These advantages include accurate skin and proximity effect modeling, above-ground cable modeling, modeling of stranded wires in cables, representation of multilayer soil, coupled overhead lines and underground cables, etc. This paper presents the new tool together with demonstrations of transient simulations for practical examples. [ABSTRACT FROM AUTHOR]

• The cable as a down-lead for a composite pylon is studied by simulation. The dynamic capacitance of the corona emanating from the dielectric has been obtained by experiments. • The effects of the corona on the cable down-lead on the overvoltage and lightning performance have been analyzed. • The phase voltage effect on the pylon critical current has been explored. This paper investigates the effect of the impulse corona inside the cross-arm on the lightning performance of a Y-shaped composite pylon with a cable as an internal down-lead through the hollow cross-arm. First, the electromagnetic transient model for the down-lead system of the composite pylon is built. The simplified steps for calculating the surge impedance of the cable down-lead are given. In addition, the mutual coupling between two down-leads is considered. Through a laboratory test on coaxial cylinders resembling the structure of the cable and cross-arm, the dynamic capacitance of the corona on the surface of the cable is obtained and included in the electromagnetic transient model. Then, the effect of the corona on the traveling waveform and mutual capacitance is discussed. Furthermore, the influences of the ground electrode length and the phase voltage on lightning performance are also studied. Finally, the backflash rates of the composite pylon with cable as down-lead are calculated. The results show that the impulse corona has a limited impact on the critical current, and the composite pylon with cable as down-lead shows a promising lightning performance. [ABSTRACT FROM AUTHOR]

This paper looks back at forty years of U.S. communications policy, and concludes that all of the challenges that were salient when Telecommunications Policy published its first issue—the lack of competition in CPE, long distance, local telephone service, television networks, and multichannel video program distribution—have essentially been addressed. The other technology that has grown in importance since 1976—the Internet—is widely regarded as a raging success. Although no history is completely uniform, the past forty years illustrates the key considerations underlying the choice between whether to impose access regulations or whether to rely on facilities-based competition. Moreover, the paper considers the important role that U.S. courts have played in promoting competition and consumer welfare. In many cases, timely judicial intervention has forced regulators to retreat from positions that protected incumbents and limited competition. The paper concludes with outlooks on new issues and debates that will continue to arise. [ABSTRACT FROM AUTHOR]

In the current work, we present a planar elastoplastic finite element model for the simulation of the mechanical response of helical constructions to traction loads. We elaborate a numerical scheme that employs a detailed description of the helical geometry and characterizes its coupled axial and torsional response. We validate the modelling results with well-established three-dimensional (3D) finite element schemes. For the validation, a single layer helical strand with different construction parameters is employed. Additional analysis is carried out to highlight the role of hardening, providing useful insights in the effect of loading history on the structure’s macroscopic elastoplastic response. Overall, a low computation cost elastoplastic modeling scheme, suitable for large-scale structural analysis of helical constructions is presented. [ABSTRACT FROM AUTHOR]

The modeling of iced suspended cables under wind excitation is developed basing on aerodynamic elements superimposed on corotational beam finite elements. Eccentricity of the ice coating is accounted for and aerodynamic loads include the aerodynamic moment. The proposed formulation, applied to a suspended cables of the literature, highlights the importance of the eccentricity of the ice coating on the critical conditions for galloping and on the post-critical behavior. [ABSTRACT FROM AUTHOR]

The analysis of high-frequency wave propagation in arbitrarily shaped waveguides requires specific numerical methods. A widely spread technique is the so-called semi-analytical finite element (SAFE) formulation. This formulation enables to account for the translational invariance of waveguide problems and leads to a two-dimensional modal problem reduced on the cross-section. Despite this, solving the problem can still be computationally demanding. In order to further reduce the size of the modal problem, this paper presents a SAFE method for waveguides of rotationally symmetric cross-sections. Such structures are encountered in many applications. Typical examples are bars of circular cross-section, regular polygons, and multiwire cables. Numerical results show that the computational effort required for solving the SAFE modal problem is tremendously reduced by accounting for rotational symmetry. [ABSTRACT FROM AUTHOR]

The main objective of this work is the analysis of the dynamic behavior of new transmission line cables: Tern (CAA), CA 1120 and CA 6201 (alloy); with mechanical tension variable (7 to 36% of the ultimate tensile strength (UTS)) with and without the inclusion of Stockbridge dampers. In order to achieve these objectives a procedure is used based on experimental data obtained by dynamic tests and numerical data obtained through computer simulation of mathematical models (linear and nonlinear) obtained by the finite element method. For low cable load, the nonlinear behavior is accentuated and the results obtained by nonlinear modeling exhibit good accord with the experimental modal data. With an increased cable load, numeric data obtained through the linear and non-linear models are close. [ABSTRACT FROM AUTHOR]

This work proposes a new cable tension identification technique based on a static inverse method that, by coupling a universal cable model with displacement and strain sensors data, exploits the differences between the original cable equilibrium problem and that of the cable loaded by a suitable added mass. The formulated inverse problem thus defines a data misfit functional based on the differences in terms of transverse displacements and elongations between the two equilibrium configurations. The inverse problem is implemented in a two-step identification procedure. First, the axial stiffness and mass per unit length are kept constant and the length of the cable is approximately found via a simple line search algorithm using finite differences to estimate the functional derivatives. Second, the other physical parameters are assessed using an adjoint method for which the direct problem, the adjoint problem and the parameters sensitivities are found as derivatives of a Lagrangian functional with respect to dual variables, primary variables, and parameters, respectively. Due to the ill-conditioning nature of the problem, the proposed method does not allow an exact parameter identification but it does lead to an acceptable tension assessment. An experimental test campaign conducted on a multilayered stranded cable 21 m long and 22 mm in diameter subject to several tension levels confirms the relevance and operational feasibility of the proposed inverse method. [ABSTRACT FROM AUTHOR]

This paper reports the first aero-elastic test conducted under a scaled downburst wind field at the WindEEE dome facility at the University of Western Ontario, Canada. The main purpose of the test is to assess the dynamic response of a multi-span transmission line. The study starts by providing a characterization of the downburst wind field produced in WindEEE including a comparison with results of previously conducted numerical simulations. A number of test configurations, involving different locations of the downburst relative to the line, is considered. A decomposition approach is developed to separate between the resonant and the background components of the response. The results are presented in the form of a dynamic magnification factor that relates the peak response including the dynamic effect to the maximum quasi-static response. The test results show that the resonance contribution ranges between 5% and 10% of the peak response for the tower. They also show that the dynamic response of the conductors can reach up to 30% and 12% of the peak response at low and high downburst speeds, respectively. [ABSTRACT FROM AUTHOR]

In this paper, the lightweight concrete made from cable, polystyrene and ethylene vinyl acetate (EVA) waste was studied. EVA waste from footwear industry, waste from electrical cable and waste polystyrene were used as an aggregate in the lightweight concrete. This idea was prompted by lack of polystyrene in the market and also large amounts of waste of foamed plastics, for which the application is looking for opportunities. Further aspect was that production of polystyrene pearls, used as a filler of lightweight concrete, it is very costly. The plastic waste was used as the only aggregate or as a combination EVA-cable and EVA-polystyrene in a ratio of 1:3, 1:1 and 3:1. The water-cement ratio of 0.50 and the dose of cement – 175 kg/m3 were used for all mixtures. For lightweight concrete were verified particularly density, strength characteristics and heat-technical characteristics. [ABSTRACT FROM AUTHOR]

Acetabular fractures potentially account for up to half of all pelvic fractures, while pelvic fractures potentially account for over one-tenth of all human bone fractures. This is the first biomechanical study to assess acetabular fracture fixation using plates versus cables in the presence of a total hip arthroplasty, as done for the elderly. In Phase 1, finite element (FE) models compared a standard plate method versus 3 cable methods for repairing an acetabular fracture (type: anterior column plus posterior hemi-transverse) subjected to a physiological-type compressive load of 2207 N representing 3 x body weight for a 75 kg person during walking. FE stress maps were compared to choose the most mechanically stable cable method, i.e. lowest peak bone stress. In Phase 2, mechanical tests were then done in artificial hemipelvises to compare the standard plate method versus the optimal cable method selected from Phase 1. FE analysis results showed peak bone stresses of 255 MPa (Plate method), 205 MPa (Mears cable method), 250 MPa (Kang cable method), and 181 MPa (Mouhsine cable method). Mechanical tests then showed that the Plate method versus the Mouhsine cable method selected from Phase 1 had higher stiffness (662 versus 385 N/mm, p = 0.001), strength (3210 versus 2060 N, p = 0.009), and failure energy (8.8 versus 6.2 J, p = 0.002), whilst they were statistically equivalent for interfragmentary sliding ( p ≥ 0.179) and interfragmentary gapping ( p ≥ 0.08). The Plate method had superior mechanical properties, but the Mouhsine cable method may be a reasonable alternative if osteoporosis prevents good screw thread interdigitation during plating. [ABSTRACT FROM AUTHOR]

It is reasonable to develop models and to investigate the dynamic behaviour of systems composed of cables since cable vibration can have an important effect on the motion of these mechanical systems. This paper deals with the application of the nonlinear formulation for flexible body dynamics called the absolute nodal coordinate formulation (ANCF). It is used for modelling the systems composed of cables, pulleys, other rigid bodies and a motor with prescribed motion. The ANCF was chosen as a suitable approach, which that can allow to consider a detailed interaction of the cable and the pulley with its nonlinear dynamical behaviour. The ANCF uses absolute positions of nodes (reference vectors) and slopes (reference vector derivations) as a set of nodal coordinates. An in-house modelling tool in the MATLAB system was created based on the proposed modelling methodology and two case studies were performed. A simple system containing a pulley and a cable with two attached bodies was used in order to test the simulation tool based on the proposed modelling methodology with respect to different parameters. A more complex mechanical system composed of a driven weight joined with a motor by a cable led over a pulley was numerically and also experimentally investigated. The comparison of obtained numerical and experimental results shows sufficient agreement and proves that the proposed modelling approach can be used for dynamic analyses of such systems. [ABSTRACT FROM AUTHOR]

The vulnerable transverse behavior of the carbon-fiber-reinforced polymer/plastic (CFRP) restricts the application of CFRP cables in bridges, when considering the possible collisions from vehicles. This paper presents an experimental investigation on the transverse impact behavior of the CFRP cable system. Drop-weight impact tests were conducted on six specimens. Each specimen composed of a seven-wire CFRP strand and two reactive powder concrete (RPC)-grouted bond-type anchors at both ends. Test results showed that the RPC grouted bond-type anchor provided a reliable anchorage to the CFRP strand during both single and multiple impacts. For single impact of a specimen under a pretension of 40 kN, the average transverse impact resistance and energy dissipation capacity were approximately 16 kN and 727 J, respectively. The successive two impacts induced damage led to reductions of 37% in transverse resistance, 30% in maximum cable tension, 39% in transverse stiffness, 20% in energy dissipation capacity. A modified SDOF model based on nonlinear geometric stiffness and available impact energy was established for the prediction of the impact force and deflection of a CFRP cable under single and multiple impacts. [ABSTRACT FROM AUTHOR]

Sea electrodes have been used since the first HVDC subsea links were installed in the 1950s and provide a simple proven solution for the return current path. Today around 30% of the approximately 40 HVDC subsea links in service use sea electrodes as the return current path under normal or emergency operation conditions. This paper reviews the evolution of interconnectors with sea electrodes and the factors, such as location, environmental impact, current capacity and financial factors (cost, flexibility, losses) which need to be assessed before adopting a sea electrode. In particular findings from environmental studies undertaken on existing sea electrodes are reviewed, as well as, the detailed content of recent Environmental Impact Statements for HVDC projects with proposed sea returns. Finally, the reasons for a change in design on links with a proposed sea return to a metallic return are also considered. [ABSTRACT FROM AUTHOR]

Introduction: Anatomical reduction of displaced acetabular fracture is not without its' limitations and complications. This study is conducted to assess clinical and radiological outcomes as well as complications of treating displaced acetabular fractures with emphasis on anatomical reduction in weight-bearing area, mainly the posterior column, and imperfect reduction of the anterior column is acceptable. However, stability of both columns is mandatory.Methods: It was a retrospective study carried out in a Level 1 arthroplasty and trauma centre. 23 patients (17 males, 6 females) with average age of 50.1 years (range, 36-68 years) with displaced acetabular fracture treated with combined incisions and plate-cable systems were included. There were 3 elementary and 18 associated fractures according to Letournel classification. Average follow-up was 23.5 months (range, 12-38.7 months). Mean operation time was 160min (range: 75-320min). Functional scores were evaluated using Harris Hip Score (HHS) whilst reduction was assessed by Matta criteria. Any displacement of reduction, osteoarthritis, heterotopic ossification, and other complications was recorded.Result: 65.2% (15/23) of the patients obtained excellent HHS and 21.7% (5/23) had good HHS. There were 12 anatomical, 6 imperfect, and 5 poor reductions. No displacement was recorded in final follow-up. Complications documented: three lateral femoral cutaneous nerve injuries, two conversions to total hip arthroplasty, three Brooker stage 1 heterotrophic ossification, one pulmonary embolism and one screw irritation. No incidence of wound breakdown, infection and radiological osteoarthritis was reported.Conclusions: Imperfect reduction of the anterior column provided clinical outcomes that are as good as total anatomical reduction. This approach minimizes soft tissue damage and reduces perioperative morbidities. [ABSTRACT FROM AUTHOR]

The tensegrity robot consisting of rigid rods and flexible wires can vary its shape by changing rod- or wire-lengths or both. This paper presents a prototype tensegrity, which can vary its shape to switch between two types of locomotion (rolling and gain). The prototype possesses three rods and nine wires, and can change shape by changing the wire-lengths. In this paper, the aspect of the prototype is introduced, and its experimental result obtained using a basic PD controller is demonstrated. Furthermore, a calculation method for balancing internal forces among wires is proposed. [ABSTRACT FROM AUTHOR]

In this paper, a concept of using rolling joints for a multistable structure, which deforms elastically into a variety of cylindrical shapes, is presented. A bistable joint is obtained by modifying the geometry of a rolling hinge. The proposed concept can hold the stable state without any continued actuation. Then detailed mathematical derivations are carried out to obtain the wire tensions and joint resultant moment during the motion, which are used to compute the external action that should be applied to move the joint. The effects of some geometric parameters on the mechanical behavior are also investigated. The results show that higher values of the wire tension and joint resultant moments can be obtained by increasing the side included angle φ or the radius of wire wrapped circles R . Moreover, the pretension of wires in the stable configuration also increases the wire tension and the joint resultant moment. [ABSTRACT FROM AUTHOR]

Free vibration tests are often performed for the dynamic characterization of structural systems and components. In the field of road bridges monitoring, such tests require minimal equipment (i.e., a sparse network of few sensors, even a single one) in order to gather – quickly and at low cost – some essential information about the dynamic behavior of the structure. The experimental free-vibration response is thus processed for estimating structural modal features which, in turn, can be useful to corroborate or update available numerical models as well as to evaluate current bridge conditions. Within this framework, an efficient computational strategy is here developed for the modal identification of bridges based on their free vibration response. The procedure combines the variational mode decomposition technique with the area ratio-based damping identification method, which ensures enhanced robustness to noise-related effects in field-test signals. A novel procedure is implemented to make the whole identification process fully automatic, in such a way that it does not depend on specific structural features (e.g., to identify even closely-spaced modes) or subjective user's settings. After a preliminary validation with a synthetic multi-modal signal, the proposed procedure is applied to two real case-studies. The first case-study deals with the identification of natural frequencies, modal damping ratios and mode shapes of prestressed concrete girder bridge decks. Particularly, experimental natural frequencies and mode shapes are compared with numerical predictions obtained from a finite element model of the bridge. The dynamic characterization of the cables of a cable-stayed bridge is considered in the second case-study. Herein, experimental natural frequencies of all the stay-cables are initially analyzed for estimating their stress levels, which have been critically analyzed to detect the existence of relaxation losses. Moreover, modal damping ratios of all the stay-cables are identified and compared to estimates obtained by alternative ambient-vibration-based techniques. • Variation mode decomposition with fully automatic implementation procedure. • Damping ratio identification via area ratio-based approach with enhanced robustness to noise. • Efficient performance to identify closely spaced modes, no subjective user's settings. • Complete identification of prestressed concrete bridge decks compared to FEM results. • Dynamic characterization of cable-stayed bridges and identification of cable relaxation losses. [ABSTRACT FROM AUTHOR]

This research investigates the short-distance hydrodynamic interaction of a squat submarine towed by a marine vessel. A one-tenth scaled captive model of a 0.625-m squat submarine is constructed along with a 1.5-m Fridsma ship to perform 69 unique experiments in a 4 × 6 × 400-m3 water tank located in a towing tank center. The submarine model is a new mini-submersible, Apam-Napat SMSD type, with an L/D ratio below four. The cable is specified, regarding its weight per unit length, using a scaling method introduced in this paper. The submarine-cable-ship system is tested for nine various relative lengths and depths at short-distance conditions. In each case, drag and heave forces are recorded and presented for the vessels using resistance tests at velocities of 0.5, 1.0, and 1.5-m/s. Finally, outputs are extended to develop 2-dimensional contours to estimate the interactional forces in the full domain. The results show a critical zone behind the ship around a depth of 0.75D where ship drag forces are increased by up to 177% compared to free-running conditions. In addition, comparing the towing mechanism to self-propelling operations shows that the towing effect dominates vessel interaction, increasing the drag forces by up to 240% when the ship tows the submarine. • Heave and drag forces are evaluated for the interaction of a submarine-cable-ship system. • Critical areas are identified where the magnitude, or variation, of interaction forces is significant. • A set of contours is presented to show interactional forces over the entire domain. • Investigation of the cable behavior according to Taut and Catenary mooring theories in different testing locations. • Towing a submarine makes larger interaction compared to self-propelling arrangement. [ABSTRACT FROM AUTHOR]

Most current designs for Submerged Floating Tunnels (SFT) include a mooring system to fix the position of these floating structures. Long period waves, such as swell waves, parametrically excite the system and might result in excessive vibrations in the cable. This paper presents two distinct studies. First, an analytical investigation of the system's stability is performed to derive a closed-form expression, which allows for a quick evaluation of the system's stability. This expression is obtained through the Harmonic Balance Method (HBM) with two harmonic terms. The contribution of multiple modes of vibration is investigated for the case of small sag to span ratios. The expression is compared with the results from a numerical model, revealing the applicability of the proposed formulation. The second study investigates the tension in the mooring line during parametric excitation. Correct design should avoid excessive forces that might break the line or very small forces that lead to momentarily slack cables. Thus, the aim of this study is to assess the validity of using the stability charts for the design of mooring lines with respect to safe levels of cable forces. This is achieved through the numerical analysis of a cable model using Abaqus. Cable vibrations and cable forces are compared for a range of amplitudes and frequencies of the support motions. [ABSTRACT FROM AUTHOR]

This study compared surface soil moisture from 11 separate remote sensing and modelled products across Australia in a common framework. The comparison was based on a correlation analysis between soil moisture products and in situ data collated from three separate ground-based networks: OzFlux, OzNet and CosmOz. The correlation analysis was performed using both original data sets and temporal anomalies, and was supported by examination of the time series plots. The interrelationships between the products were also explored using cluster analyses. The products considered in this study include: Soil Moisture Ocean Salinity (SMOS; both Land Parameter Retrieval Model (LPRM) and L-band Microwave Emission of the Biosphere (LMEB) algorithms), Advanced Microwave Scanning Radiometer 2 (AMSR2; both LPRM and Japan Aerospace Exploration Agency (JAXA) algorithms) and Advanced Scatterometer (ASCAT) satellite-based products, and WaterDyn, Australian Water Resource Assessment Landscape (AWRA-L), Antecedent Precipitation Index (API), Keetch-Byram Drought Index (KBDI), Mount's Soil Dryness Index (MSDI) and CABLE/BIOS2 model-based products. The comparison of the satellite and model data sets showed variation in their ability to reflect in situ soil moisture conditions across Australia owing to individual product characteristics. The comparison showed the satellite products yielded similar ranges of correlation coefficients, with the possible exception of AMSR2_JAXA. SMOS (both algorithms) achieved slightly better agreement with in situ measurements than the alternative satellite products overall. Among the models, WaterDyn yielded the highest correlation most consistently across the different locations and climate zones considered. All products displayed a weaker performance in estimating soil moisture anomalies than the original data sets ( i.e. the absolute values), showing all products to be more effective in detecting interannual and seasonal soil moisture dynamics rather than individual events. Using cluster analysis we found satellite products generally grouped together, whereas models were more similar to other models. SMOS (based on LMEB algorithm and ascending overpass) and ASCAT (descending overpass) were found to be very similar to each other in terms of their temporal soil moisture dynamics, whereas AMSR2 (based on LPRM algorithm and descending overpass) and AMSR2 (based on JAXA algorithm and ascending overpass) were dissimilar. Of the model products, WaterDyn and CABLE were similar to each other, as were the API/AWRA-L and KBDI/MSDI pairs. The clustering suggests systematic commonalities in error structure and duplication of information may exist between products. This evaluation has highlighted relative strengths, weaknesses, and complementarities between products, so the drawbacks of each may be minimised through a more informed assessment of fitness for purpose by end users. [ABSTRACT FROM AUTHOR]

Cables are main bearing elements of cable-stayed bridges and can transfer loads from decks to towers. Such elements are significantly influenced by wind-rain-induced vibration. The reliable operation of the cables is extremely essential, especially when undergoing typhoons. The existing studies only identify the tension once an hour or 6 h, unable to reflect the instantaneous variation of tension. To this end, the identification of time-varying cable tension during typhoons is still a pending issue, not been resolved well. To address this issue, this study is concerned with the identification of time-varying cable tension during typhoons based on a Synchrosqueezing Wave-packet-based Instantaneous Frequency Tracking (SWIFT) algorithm. The algorithm is pretty sophisticated to first extract the time-varying instantaneous frequency via acceleration responses and then identify the variation trend of typhoon-induced tension. A field experiment on the Sutong Yangtze River Bridge (SYRB) undergoing severe typhoon Rumbia is exemplified as an engineering case to verify the method by using it to process health monitoring data. Besides, the wind characteristics, structural deformations, and displacement responses are also scrutinized to clarify the features of the variation of tensions. The results show that the proposed algorithm can identify the time-varying tension of cables during typhoons and has the potential to support a system of real-time identification and assessment of cable tension in extreme events. • Identification of time-varying tension of a long-span bridge during a typhoon. • Investigation of the relationship between tension and wind loads during a typhoon. • Evaluation of service performance of cables according to several indices. • Reveal the significant correlation between cable tension and other monitoring data. [ABSTRACT FROM AUTHOR]