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Detailed productivity studies were conducted on three distinct crews, all operating the modern version of the EMS Harvestline excavator-based yarder working with a motorized grapple carriage for harvesting radiata pine from plantation forests in New Zealand. Data were collected from over 1000 cycles and used to estimate robust productivity benchmarks and models. Mean productivity neared 100 t per productive machine hour (PMH) on short distances (100 m) and decreased to <70 t PMH−1 on longer ones (>200 m). In addition to very fast cycle times, only 1.5 min on average at 100 m, large stem size contributed to those very high productivity figures. Utilization ranged from 50% to 63%, with line-shifts and yarder relocation being a common delay type given the short corridors and quick extraction cycles. Productivity was 40–60 t per scheduled machine hour. This productivity range is comparable with those obtained by heavier and more expensive purpose-built swing yarders, showing great potential for cost-effective future applications. [ABSTRACT FROM AUTHOR]

Crosslinked polyethylene cable is an important equipment in 10 kV distribution system, and its safety is very important. Making scientific judgments on cable repair decisions can help improve the safety and reduce the economic cost. In view of this, a cable risk assessment and repair decision method based on K‑means clustering and random forest(RF) classification model is proposed. The method first defines the risk level and risk degree of the cable based on the insulation status of the cable. Then the K‑means clustering algorithm is used to cluster the multi‑aging index dataset and classify the risk level intervals to build a multi‑aging index risk matrix. Based on the risk matrix of the multi‑aging index, the classification labels corresponding to the multi‑aging index are determined by using the comprehensive weight method. Finally, the classification model of the repair ways of the cables is established and trained based on the RF algorithm, and the selection results of the repair ways are output. The average accuracy of the proposed method reaches 99.70%, achieving rapid and reliable repair decisions for cables. [ABSTRACT FROM AUTHOR]

During the construction of cable joints, three common defects may occur on the XLPE surface: scratches, moisture exposure, and adhered contaminated particles. To evaluate the impact of these defects on joint performance, this paper establishes a sheet model of XLPE insulation in cable joints to analyze the changes in the electric field under different defects and explore the influence of different defects on the electric field and breakdown voltage. Results of the study reveal that the electric field at the scratch site on XLPE produces severe distortion, being 1.6 times that of non-scratch areas. When exposed to moisture, the more conductive impurities present in the adhered contaminated water on the XLPE surface, the higher the conductivity of the contaminated water, thereby increasing its conductive performance and the electric field strength, which is 1.22-1.4 times that of the non-moist interface. When particles adhere to the XLPE surface, severe distortion occurs at the particle-interface electric field, approximately 1.5 times that of the defect-free interface. Scratches have the most significant impact on the electric field of XLPE insulation. Experimental results also demonstrate that the breakdown voltage without defects is 129.6 kV, while the breakdown voltage with scratch defects is 59.1 kV, moisture defects is 69.7 kV, and particle contamination defects is 59.2 kV, with scratches having the most significant impact on the breakdown voltage of XLPE insulation. These findings provide important insights into the influence of different defects on the insulation performance of cable joints. [ABSTRACT FROM AUTHOR]

Extensive vehicle fires threatening suspension bridges in the last decade have aroused an emerging demand to estimate the fire safety of hanger systems. One of the paramount tasks for evaluating the fire resistance of hangers is to calculate their temperatures. However, as plans always lag behind events, no competent temperature calculation methods are available now for engineers, whether vehicle fire models, thermal boundaries on hanger surfaces, or cross-sectional heat transfer formulations. This paper addresses these three issues and then proposes an integrated framework for assessing the thermal response of hanger systems subjected to vehicle fires. Vehicular fires were classified into five grades, adapted to cars, buses, light goods trucks, medium goods trucks, and tanker trucks, respectively. This hierarchy was validated using 16 full-scale vehicle fire tests in opening or tunnel conditions. An empirical formulation of thermal radiation developed for pool fires was adopted to envelope the heat flux applied by passenger vehicle fires on the hanger surface and was validated using five tests. Radiation from truck fires was constructed using a cuboid solid radiative flame. The spatial heat fluxes surrounding Grade-5 vehicle fires typified by tanker fires were computed using the computational fluid dynamics method validated by two large-scale outdoor trench fires. With these quantitative thermal boundaries on hanger exteriors, the transient temperature across the hanger section was derived using the lumped capacitance method, validated by finite-element models in various scenarios. As a multigrade temperature estimation methodology proposed for hangers subjected to vehicle fires, this method is easy to implement. It can serve in future structural fire design of critical suspension bridges with high exposure risks to vehicle fires. [ABSTRACT FROM AUTHOR]

This essay examines "process" discourse and the politics of reassurance across the prototypically American media domains of reality TV and cable news. Using The Bachelorette 's 2020 season and CNN's concurrent coverage of 2020s famously disputed presidential election as case studies, it argues that both broadcasts' copious references to the soundness of the "processes" they purport to depict both naturalize and stabilize the tenuous notions of heterosexuality and democracy on which they rest. The two programs' exemplary televisual "process" discourse reassures even cynical viewers that, though much of the pleasure US audience-members take in their broadcasts derives from the spectacle (or threat) of dysfunctionality, we can ultimately rely on the functionality of the systems that govern our lives. Not least, it courts the perception that television is the true arbiter of "the process," and thus that TV itself deserves Americans' trust—a vitally important impression to maintain during a global pandemic. [ABSTRACT FROM AUTHOR]

This article analyzes American cable channel HGTV's programing strategies in response to the COVID-19 pandemic, and specifically their construction of a "COVID-free" fantasia in their series Home Town and its spinoff, Home Town Takeover. By considering this response through the lens of dissonance, I argue that while the network originally emphasized their social responsibility to mitigating the spread of the virus, their business model incentivized them to move past the virus more swiftly than other channels, pushing the labor of mediating dissonance onto their on-screen talent and their audience. This case study foregrounds how variables like genre, channel, and audience shaped the television industry's response to the pandemic, with HGTV's business model built on "evergreen" reality programing leading them to abdicate principles of social responsibility both more quickly and more thoroughly, despite numerous options that would have addressed the dissonance of COVID in a more balanced fashion. [ABSTRACT FROM AUTHOR]

Extended deflection theories for live load analysis of self-anchored suspension bridges (SASB) involving regular or floating types of girders are derived employing both direct equilibrium method and an energy principle. Subsequently, a simplified FE formulation with hanger extensibility is presented to numerically solve the developed theories. To showcase the validity and precision of the present formulations, a typical SASB model is analyzed, with subsequent comparison of analysis outcomes against those derived from the unstrained length method (ULM). In particular, extensible/inextensible effects of hanger cables, boundary conditions of regular/floating girders, and initial camber effects are intensively investigated. Finally, the most suitable deflection theories for live load analysis of both regular and floating SASB are determined. [ABSTRACT FROM AUTHOR]

With the implementation of the GOELRO plan in the late 1920s and early 1930s, efforts were made to extend the use of electricity to agricultural fieldwork through the development of specialized machines and mechanisms. Numerous inventors, engineers, and scientists focused on finding ways to electrify energy-intensive agricultural operations. As a result, various designs of electric plows and electric tractors emerged. (Research purpose) The paper aims to analyze the development of electric tractors in the USSR during the period from 1930 to 1956. (Materials and methods) The study employs a chronological research method, examining scientific and technical publications, along with other sources, that address the manufacturing and testing of electric tractors. Conclusions were drawn through the analysis and synthesis of the reviewed materials. (Results and discussion) The initial phase of electrifying soil cultivation operations was marked by the development of plows powered by electric winches. In the early 1930s, tractors emerged with electric motors replacing traditional heat (internal combustion) engines. Advancements in electric tractor design led to the creation of tracked models such as the HTZ-15 (Kharkov) and ET-5-ENIN-VIESh (Moscow), which underwent extensive economic testing. The results indicated that the use of electric tractors in fi eld crop farming was unsuitable due to both technical and economic factors. (Conclusions) Between 1930 and 1956, at least 15 types of wheeled and tracked electric tractors were developed in the Soviet Union. Testing these models revealed both the advantages and drawbacks of electrified traction equipment. Despite their eff orts, mid-twentieth-century engineers were unable to resolve the technical challenges associated with the implementation of electric tractors, leading to the termination of the project in 1956.

Abstract This paper primarily explores the modeling method of n-level complex helical structures with coal mining machine cables as the research object. The paper first elaborately introduces the modeling method of n-level helix curves based on parametric equations and coordinate transformations, and compensates for the n-level helix curves with corrected pitch, which can obtain more accurate n-level helix curves and improve the accuracy of n-level helix curves modeling. Subsequently, based on this high-precision n-level helix curves modeling method, the paper elaborates on the method of solving pitch and twisting radius of multi-layer helical structure. Calculation scripts were written based on the above methods, which can be used to batch calculate the twisting radius and pitch of each layer structure in multi-layer structures when satisfying the conditions of in-layer tangency, inter-layer tangency, and extrusion deformation, and retain the actual results through logical judgment. Then, based on the above two methods, the paper developed a modeling method for braided structures based on piecewise functions containing fifth-order polynomials, which can effectively avoid the problem of insufficiently dense arrangement of braided lines and easy interference in traditional methods. Finally, a set of modeling tools was developed using C# and Python in Grasshopper to implement the modeling algorithm. Taking the MCPT-1.9/3.3 3120 + 170 + 4 * 10 coal mining machine cable as an example. The cable was modeled using both the method proposed in this paper and the traditional method. Comparative data shows that the method proposed in this paper can reduce errors by 3.31E6 times in the second-level and above helical structures. In addition this paper compares the standard line length, measured line length, and the line length established by the proposed model, showing that the relative errors are both less than 0.1941%. This paper provides a new, systematic, high-precision, and full-process cable modeling method, in which all parameters except the process parameters are accurately solved by equations. It lays a theoretical foundation for the high-precision simulation and intelligent sensing cables, which is of great significance for improving the safety, stability, and efficient development of the coal mining industry. The research results of the paper can not only be applied to the modeling of coal mining machine cables but also can be extended to the modeling of other complex multi-layer helical structures.

Identifying cable insulation defects is crucial for preventing system failures and ensuring the reliability of electrical infrastructure. This paper introduces a novel method leveraging the Markov transition field (MTF) and Transformer network to improve the precision of cable insulation defect identification and enhance the algorithm's noise resistance. Firstly, the algorithm performs modal transformation on the time series data acquired by the ultrasonic probe through MTF, generating corresponding images. Following this, the image data are input into a pre-trained Transformer network to achieve automated feature extraction. Subsequently, a multi-head attention mechanism is introduced, which assigns weights to the features extracted by the Transformer network, thereby emphasizing the most critical information for the identification task. Finally, more accurate defect identification is achieved based on the weighted features. The results demonstrate that this method achieves higher accuracy and stronger noise resistance compared to traditional image processing and recognition methods, making it a robust solution for cable insulation defect identification. [ABSTRACT FROM AUTHOR]

Cable insulation defect detection ensures electrical safety, prevents accidents, extends equipment life and guarantees stable system operation. For the traditional cable insulation defect detection and identification of difficult problems, this paper proposes the use of ultrasonic cable insulation defect detection and combined with the Convolutional Neural Network (CNN)-transformer model of cable insulation defect classification method. Firstly, the ultrasonic probe is used to obtain different cable insulation defect signals, and then the CNN-transformer model is used to classify different cable insulation defects. The CNN is used to initially extract the characteristics of the cable insulation defects from the input signals, and then the multi-attention mechanism in the time series Transformer is used to extract the transient local and periodic global characteristics of the cable insulation defect signals. The deeper transient local features and periodic global features of the cable insulation defect signal are extracted by the multi-attention mechanism in the time series Transformer; finally, the recognition results are outputted by the fully connected layer and softmax classifier. The results show that ultrasonic reflection and transmission phenomena occur at the defects, and different defects can be accurately reflected by the defect echo time and amplitude, and the accuracy of cable insulation defect recognition using the CNN-transformer model reaches 100%, with good generalization ability. [ABSTRACT FROM AUTHOR]

This paper primarily explores the modeling method of n-level complex helical structures with coal mining machine cables as the research object. The paper first elaborately introduces the modeling method of n-level helix curves based on parametric equations and coordinate transformations, and compensates for the n-level helix curves with corrected pitch, which can obtain more accurate n-level helix curves and improve the accuracy of n-level helix curves modeling. Subsequently, based on this high-precision n-level helix curves modeling method, the paper elaborates on the method of solving pitch and twisting radius of multi-layer helical structure. Calculation scripts were written based on the above methods, which can be used to batch calculate the twisting radius and pitch of each layer structure in multi-layer structures when satisfying the conditions of in-layer tangency, inter-layer tangency, and extrusion deformation, and retain the actual results through logical judgment. Then, based on the above two methods, the paper developed a modeling method for braided structures based on piecewise functions containing fifth-order polynomials, which can effectively avoid the problem of insufficiently dense arrangement of braided lines and easy interference in traditional methods. Finally, a set of modeling tools was developed using C# and Python in Grasshopper to implement the modeling algorithm. Taking the MCPT-1.9/3.3 3120 + 170 + 4 * 10 coal mining machine cable as an example. The cable was modeled using both the method proposed in this paper and the traditional method. Comparative data shows that the method proposed in this paper can reduce errors by 3.31E6 times in the second-level and above helical structures. In addition this paper compares the standard line length, measured line length, and the line length established by the proposed model, showing that the relative errors are both less than 0.1941%. This paper provides a new, systematic, high-precision, and full-process cable modeling method, in which all parameters except the process parameters are accurately solved by equations. It lays a theoretical foundation for the high-precision simulation and intelligent sensing cables, which is of great significance for improving the safety, stability, and efficient development of the coal mining industry. The research results of the paper can not only be applied to the modeling of coal mining machine cables but also can be extended to the modeling of other complex multi-layer helical structures. [ABSTRACT FROM AUTHOR]

In a suspension bridge, slippage may occur at the saddle–cable interface during an earthquake. A refined finite element model of the saddle–cable interface is proposed which considers the compressive force and friction force at the curved contact surface. To investigate the saddle–cable slippage during an earthquake, the finite element model of a suspension bridge was built, and nonlinear time history analysis was conducted. Furthermore, the effects of the friction coefficient at the saddle–cable interface, the pounding between the suspension bridge and the approach bridges, the fluid viscous damper, and the rigid central buckle were evaluated by parametric analysis. The result shows that the saddle–cable slippage affects the overall seismic response of the suspension bridge slightly. The saddle–cable slippage is affected significantly by the friction coefficient of the saddle–cable interface, fluid viscous damper, and the rigid central buckle. [ABSTRACT FROM AUTHOR]

Temperature is an important factor for the service life of cable insulation. To ensure safety, the operating temperature of cables must be monitored. Since optical fiber temperature measurement technology is difficult to be used widely in medium voltage (MV) cables due to cost, this paper proposes a temperature evaluation method based on wave velocity. Firstly, the dielectric constant of cross-linked polyethylene (XLPE) cable insulation under different temperature is obtained through experiment. Based on the result, the relationship curve between wave velocity and temperature is established. The asymmetry effect due to temperature gradient in the cable insulation is discussed via finite element simulation. The effectiveness of obtaining the average insulation temperature of the cable based on wave velocity is validated. In addition, the mechanism of the temperature influence on the cable insulation material's dielectric constant is analyzed by molecular dynamics simulation, which further deepens understanding of the characteristics of cable insulation materials. [ABSTRACT FROM AUTHOR]

The paper presents a dynamic model of the TMM-3M heavy mechanized bridge during the span lowering stage. The model is constructed as a multi-body mechanical system, taking into account the elastic deformation of the cable, rear outriggers, front tires, and front suspension system. It is a mechanical model driven by a cable mechanism. Lagrangian equations of the second kind have been applied to establish a system of differential equations describing the oscillations of the mechanical system and serve as the basis for investigating the dynamics of the span-lowering process. The system of differential equations is solved using numerical methods based on MATLAB simulation software. The study has revealed laws of the displacement, velocity, and acceleration of components within the mechanical system, especially those related to the bridge span depending on the choice of the drive speed of the engine during lowering by operator. The research results show that the lowering time increases from 52 seconds to 104 seconds when the engine speed decreases from 1800 rpm to 900 rpm. The tension force on the cable is surveyed to confirm the safety conditions during the span-lowering process. The study also provides recommendations for selecting appropriate engine speeds to minimize span-lowering time while ensuring the safety conditions of the TMM-3M bridge during the span-lowering process. This research is an important part of a comprehensive study on the working process of the heavy mechanized bridge TMM-3M to make practical improvements, aiming to reduce deployment time, decrease the number of deployment crew members, and increase the automation capability of the equipment. [ABSTRACT FROM AUTHOR]

In order to explore the failure mode of the cable-stayed pipe bridge under earthquake action, taking the structural system of an oil and gas pipeline–cable-stayed pipe bridge as the research object, the full-scale finite element calculation model of the cable-stayed pipe bridge–oil and gas pipeline structural system as well as the finite element calculation model considering the additional mass of the oil and gas medium and the fluid–structure interaction effect were established by using ANSYS Workbench finite element software. The stress and displacement of the cable under the earthquake action were analyzed in the time history, as were the response characteristics of the cable when subjected to both methods. The calculation results show that the overall failure of the pipeline is basically the same under the two methods. Compared with the additional mass method, the solution for the fluid–structure coupling method can be derived through a comprehensive analysis of the flow field and structure, respectively, avoiding the sudden change caused by model simplification or calculation error so that the analysis results can better simulate the actual situation. In summary, the fluid–structure interaction method enables a more precise prediction of the dynamic response of the structure, and the findings of this research can provide a theoretical foundation and technical guidance for optimizing the seismic performance of cable-stayed pipe bridges. [ABSTRACT FROM AUTHOR]

With the development of the social economy and the improvement of electrification, cables and wires play an important role in people's lives and industrial development. Meanwhile, the large-scale laying of cables has also made them a fire hazard that cannot be ignored in land construction such as residential buildings, utility tunnels, nuclear power plants, refineries, marine systems such as submarines and ships, and airborne systems such as spacecrafts and aircrafts. In this work, studies on fire the characteristics of cables and wires over the last decades have been reviewed. Based on different experimental forms and objects (laboratory wires and commercial cables), this paper summarizes the theories of the fire dynamics in wire combustion, including the models of ignition and flame propagation, the criteria for blowing off and quenching, and the critical conditions for dripping behavior. The effects of materials, layouts, and environments on wire combustion phenomena such as airflow, ambient pressure, oxygen, gravity, and orientation angle have been discussed in detail according to the theories of heat transfer and combustion. In addition, test standards and studies on the fire behavior and release of toxic gases of commercial cables have also been fully described. Through the summary of the above content, it is expected to build a preliminary theoretical framework and future research directions for researchers in the field of cable fires. [ABSTRACT FROM AUTHOR]

The identification of cross-sectional loss in cables due to corrosion is crucial for evaluating the remaining strength of bridge cables. To accurately determine the cross-sectional loss rate, this paper derived a three-dimensional magnetic dipole model for spatial cable damage. The study employed an independently designed self-magnetic flux leakage (SMFL) sensor array to detect corrosion on a bundle of 37 parallel steel wires. The analysis investigated the correlation between corrosion degrees and SMFL signal features. The results show that the spatial magnetic field inversion collected by the sensor array device is more accurate. The cable damage location can be pinpointed by observing abrupt changes in the Bx and Bz curves. Additionally, this paper introduces five corrosion characterization features, all correlated with the cable cross-sectional loss rate. However, recognition stability using a single characteristic value is insufficient. The cable cross-sectional loss rate identification method, utilizing a back propagation neural network in conjunction with multiple characteristic indicators, demonstrates robust quantitative and adaptive capabilities. The maximum relative error of this method is 7.6%, offering a new perspective for future cable damage detection. [ABSTRACT FROM AUTHOR]

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

Objective Cable‐dragged reduction and cantilever beam internal fixation can provide promising results in the treatment of atlantoaxial dislocation or instability. However, bilateral atlantoaxial joints bone autografting has not been conducted in this technique. We aim to evaluate the safety and effectiveness of bilateral atlantoaxial joints bone autografting in posterior cable‐dragged reduction and cantilever‐beam internal fixation. Methods In this retrospective study, we included 14 patients with a minimum 24‐month follow‐up from December 2019 to September 2020. The granular bone harvested from the iliac crest was packed into the bilateral atlantoaxial joints of 14 patients in posterior cable‐dragged reduction and cantilever‐beam internal fixation. X‐ray imaging and cervical computed tomography (CT) were performed during follow‐up. The time required for bone fusion was recorded. The clinical outcomes were evaluated using the JOA scores, NDI, and VAS scores. Mann–Whitney U test, the chi‐squared test, or the Fisher exact test were used to compare the two groups regarding patient characteristics, clinical outcomes, bone fusion rates, and cervical sagittal alignment. Results The operations were successfully performed in all patients without any intraoperative complications. The mean operation time was (169.64 ± 20.91) minutes, and the intraoperative blood loss was (130.71 ± 33.62) mL. All patients received satisfactory reductions and firm bony fusion at the final follow‐up. The fusion rates were 64.29% in the atlantoaxial joints and 21.43% in post bone graft area at 3 months postoperatively, and a significant difference was observed (p = 0.022). Besides, the cervical sagittal alignment in all patients was well maintained in the last follow‐up compared to preoperatively. Importantly, a complete bony fusion in the atlantoaxial joints was observed in all patients. Moreover, the JOA, NDI, and VAS scores had improved significantly at the last follow‐up. Conclusion Bone autografting of the bilateral atlantoaxial joints is a safe and effective technique to increase bone fusion rates, shorten bone fusion time, and reduce complication rates when the cable‐dragged reduction and cantilever beam internal fixation approach is used. Therefore, it is a cost‐effective surgical procedure for treating patients with atlantoaxial dislocation or instability.

With the progress of the power grid system, the coverage area of cables is widening, and the problem of cable faults is gradually coming to affect people's daily lives. While the vast majority of cable faults are caused by the ablation of the cable buffer layer, polypropylene (PP), as a common cable buffer material, has pyrolysis properties that critically impact cable faults. Studying the semiconductive buffer layer of polypropylene (PP) and its pyrolysis properties allows us to obtain a clearer picture of the pyrolysis products formed during PP ablation. This understanding aids in the accurate diagnosis of cable faults and the identification of ablation events. In this study, the effects of temperature and catalyst (H-Zeolite Standard Oil Corporation Of New York (Socony) Mobil-Five (HZSM-5)) content on the PP thermolysis product distribution were studied by using an online tubular pyrolysis furnace-mass spectrometry (MS) experimental platform. The results showed that PP/40% HZSM-5 presented the highest thermolytic efficiency and relative yield of the main products at 400 °C. [ABSTRACT FROM AUTHOR]

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

Modern distribution networks have constantly evolved to meet different requirements. Basically, increasing energy demand and supply security are the main motivation for these changes. In order to meet the increasing energy need, there are many parallel outgoing feeders in the distribution substations, and there is an intense use of underground cables to increase supply security. During single line to earth fault, zero sequence currents circulate in the system due to cable capacitive currents of underground cables. These capacitive charging currents may cause false trips in healthy sections of the network. Metropolitan distribution networks draw particular attention with distinguishing topological features which are; the usage of long-length underground cables and high number of parallel outgoing feeders. In addition, different types of earthing methods are applied. This situation eliminates the applicability of simple, unique and universal relay settings for all types of networks. As a result, the requirement of feeder-based protection hybridization, specifically tailored to the distribution network topology is inevitable. In this study, feeder-based hybrid protection methods and optimum setting values of these methods are proposed for different network topologies and different neutral earthing methods. The method-hybridization is applied to the 62-busbar distribution network to demonstrate the applicability of the proposed method. [ABSTRACT FROM AUTHOR]

Introduction: Electrical transmission lines are normally composed of large spans that have large displacements and are subject to complex three-dimensional motions. The dynamic behavior can be analyzed through non-linear mathematical models obtained by the finite element method that can be validated by experimental data. Materials and Methods: The analyses consisted of obtaining experimental data for two different tests, bending and torsion, using accelerometers placed along samples of three different cables and with varying mechanical tension. The experimental data were compared with numerical data obtained by computer simulation of mathematical models obtained by the finite element method and using 3d frame elements. For the bending tests, the natural frequencies of the first five modes of vibration were compared and for the torsion tests, the torque angle was compared. Data were adjusted using the particle swarm optimization method (PSO). Results: For all situations analyzed (different cables, tensile loads and positioning of sensors and excitation) an excellent agreement between numerical and experimental values was noted. For bending tests, numerical and experimental values of the first five natural frequencies were compared using PSO method. Differences lower than 0.5% were noted for low loading values where the nonlinear behavior of the first modes is evident. The torsional behavior was analyzed using a bench containing a lever manually excited. By minimizing a function taking into account the difference between numerical and experimental values of the twist angle, the shear modulus is adjusted using PSO method. For all situations, it was possible to obtain good agreement between numerical and experimental values of the twist angle with deviation lower than 1%. Conclusions: It was evident that the non-linear mathematical model presented good results for both the bending and torsion tests. The differences between numerical and experimental values were small with rapid convergence using the PSO method. The proposed methodology for torsion tests using a manually operated lever proved to be efficient for adjusting torsional stiffness. It was noted that the shear modulus is influenced by the position of the lever and direction of the torsion. [ABSTRACT FROM AUTHOR]

Objective: Cable‐dragged reduction and cantilever beam internal fixation can provide promising results in the treatment of atlantoaxial dislocation or instability. However, bilateral atlantoaxial joints bone autografting has not been conducted in this technique. We aim to evaluate the safety and effectiveness of bilateral atlantoaxial joints bone autografting in posterior cable‐dragged reduction and cantilever‐beam internal fixation. Methods: In this retrospective study, we included 14 patients with a minimum 24‐month follow‐up from December 2019 to September 2020. The granular bone harvested from the iliac crest was packed into the bilateral atlantoaxial joints of 14 patients in posterior cable‐dragged reduction and cantilever‐beam internal fixation. X‐ray imaging and cervical computed tomography (CT) were performed during follow‐up. The time required for bone fusion was recorded. The clinical outcomes were evaluated using the JOA scores, NDI, and VAS scores. Mann–Whitney U test, the chi‐squared test, or the Fisher exact test were used to compare the two groups regarding patient characteristics, clinical outcomes, bone fusion rates, and cervical sagittal alignment. Results: The operations were successfully performed in all patients without any intraoperative complications. The mean operation time was (169.64 ± 20.91) minutes, and the intraoperative blood loss was (130.71 ± 33.62) mL. All patients received satisfactory reductions and firm bony fusion at the final follow‐up. The fusion rates were 64.29% in the atlantoaxial joints and 21.43% in post bone graft area at 3 months postoperatively, and a significant difference was observed (p = 0.022). Besides, the cervical sagittal alignment in all patients was well maintained in the last follow‐up compared to preoperatively. Importantly, a complete bony fusion in the atlantoaxial joints was observed in all patients. Moreover, the JOA, NDI, and VAS scores had improved significantly at the last follow‐up. Conclusion: Bone autografting of the bilateral atlantoaxial joints is a safe and effective technique to increase bone fusion rates, shorten bone fusion time, and reduce complication rates when the cable‐dragged reduction and cantilever beam internal fixation approach is used. Therefore, it is a cost‐effective surgical procedure for treating patients with atlantoaxial dislocation or instability. [ABSTRACT FROM AUTHOR]

China Power Grid is actively building a new energy-based ultra-high voltage grid system. Therefore, the researches on fire safety of power grid are of great importance. This paper firstly investigates the fire accident characteristics in the substation system. With the focuses on the transformer oil fires, the early detection and early warning, modification, fire monitoring and extinguishing systems of transformer oil are reviewed. It is found that the researches on flowing and jet fires should be reinforced while modified oil and pyrolysis gas detection can be applied for reducing the fire probability. Secondly, the fire risks and characteristics of cables are summarized for the transmission and distribution lines, and the methods of early warning, fire prevention and rescue are analyzed. For the wildfire threatening the transmission and distribution cables, the characteristics of wildfire and corresponding firefighting methods are reviewed. The water mist and liquid nitrogen are identified as the most effective ways of extinguishing cable fires and advanced fire detection and long-range drone fire extinguishing technologies should be improved for wildfires. Finally, the thermal runaway mechanism and fire characteristics of LIB in the energy storage system are summarized, and the difficulties in fire extinguishing are discussed. The application of the existing fire detection system in the field of LIB is proposed, and the early warning indicators for intelligent fire protection are introduced. In the future, the intelligent fire protection systems will improve the safety of energy storage systems, and efficient test platforms and reliable test standards will continue to be demanded to reduce the likelihood of thermal runaway and fire severity. [ABSTRACT FROM AUTHOR]

It took longer time than initially expected for development of cuprate superconducting materials for practical applications. However, there are about 20 companies that manufacture and supply long conductors and bulk materials at present. Although various large‐scale projects have supported the process of material development, material and equipment developments have been progressing under the leadership of manufacturers in recent years. In this paper, current status of development of high‐temperature superconducting materials, including MgB2, which is classified as a high temperature superconductor, and their applications are summarized, along with the history, basic physical features and recent topics. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

This paper proposes a vibration model for modal analysis and vibration control of a vertical cable-dual tuned mass damper (C-DTMD) coupled system. The proposed model introduces several non-dimensional parameters to describe the in-plane vibration of the coupled system. Moreover, the phenomenon of modal split is comprehensively studied to present the complex vibration modes. Parameter analysis is conducted to show the influence of length ratio, mass ratio, damping ratio, and frequency ratio on vibration reduction. In addition, the theoretical model is verified using finite element methods. A practical vertical cable in Jiangyin Bridge with designed wind loads is chosen as a numerical example. The results show that DTMD devices can effectively reduce the modal vibration and have great potential for multi-mode vibration control of vertical cables in suspension bridges. The proposed model can accurately describe the in-plane vibration modes of C-DTMD systems and provides a basis for the optimal design of damper parameters. [ABSTRACT FROM AUTHOR]

Identifying cable insulation defects is crucial for preventing system failures and ensuring the reliability of electrical infrastructure. This paper introduces a novel method leveraging the Markov transition field (MTF) and Transformer network to improve the precision of cable insulation defect identification and enhance the algorithm's noise resistance. Firstly, the algorithm performs modal transformation on the time series data acquired by the ultrasonic probe through MTF, generating corresponding images. Following this, the image data are input into a pre-trained Transformer network to achieve automated feature extraction. Subsequently, a multi-head attention mechanism is introduced, which assigns weights to the features extracted by the Transformer network, thereby emphasizing the most critical information for the identification task. Finally, more accurate defect identification is achieved based on the weighted features. The results demonstrate that this method achieves higher accuracy and stronger noise resistance compared to traditional image processing and recognition methods, making it a robust solution for cable insulation defect identification.

Given the corrosion protection failure of the cable-stayed bridge cable in the actual project, the impressed current cathodic protection (ICCP) technology was used to carry out the anti-corrosion tests from steel wire scale to cable scale, analyze the corrosion protection characteristics of steel wire ICCP, deduce the corrosion factor ICCP diffusion model, and reveal the space ICCP mechanism of the initial damaged cable. The analysis shows that ICCP can effectively inhibit the corrosive effect of steel wires and cables, and reduce the loss of mechanical properties of steel wires. Its protective efficiency increases with an increase in the absolute value of its protective potential and decreases with an increase in the dead load level. ICCP has a blocking effect on the diffusion of corrosion factors in the cable space, and the corrosion spatial distribution range, corrosion factor concentration, and diffusion coefficient of the initial damaged cable decrease significantly with the increase in the absolute value of the protection potential. The open circuit potential moves in a positive direction with the development of the corrosion process, and the blocking effect of corrosive factor diffusion is transformed from the joint participation by sacrificial anode cathodic protection and ICCP to the dominance of ICCP.

High-voltage cables, as applied in the electro-mobility, are highly complex structures regarding their vibration behaviour. The high complexity leads to considerable uncertainty in models for a finite element method (FEM) simulation, which is shown, for example, in the contact modelling between the strands of the cable. To handle this uncertainty and model the structural dynamic, a nonparametric probabilistic approach (NPPA) with random matrices is used for the first time on high-voltage cables. This novel application of NPPA has an advantage over typical FEM analysis by using a more manageable simulation model and eliminating the need for a complex deterministic simulation model. Initially, the NPPA is analysed and enhanced, with an optimization for the dispersion parameter and a frequency shift introduced as methodological improvements. These enhancements result in a comparable scatter band of the frequency response. Following preliminary studies, the cable's dynamic behaviour is examined through experimental modal analysis, after which the dispersion parameters are computed. The NPPA is then applied to the simplified deterministic model with the calculated dispersion parameters, and a Monte Carlo simulation is done. As a result of this simulation, a scatter band is given. The results from the simulation are then compared to the results of an experiment. It is shown that the frequency response from the experiment is almost always in the inner area of the scatter band. Consequently, this innovative method can be used for a risk evaluation according to the path of the frequency response function and an evaluation of the structural behaviour.

In the paper, we addressed the simulation and numerical modeling of deformation under static loading of wire ropes used in mine hoisting installations. We presented the main types of extraction vessels (cages and skips) commonly used in the mining industry, as well as the fastening devices to the hoisting rope (DLC). A review was conducted on the primary structural models of traction cables equipping mine hoisting machines. As one of the critical assessments performed on cables in mining extraction is done at maximum static load, we constructed a virtual model of a tension testing stand for a hoisting cable using SOLIDWORKS®. Essentially, we created a virtual device in the form of an assembly consisting of multiple parts, establishing geometric connections between them. Additionally, we highlighted the cable's path over the core of the fastening device. The actual tension test was performed through a simulation under static loading of a 500 mm section of the cable. We determined the von Misses stress and overall deformations of the cable section.

The purpose of this community service activity is to educate and increase the understanding of class VII ICT students at SMP Muhammadiyah 7 Yogyakarta regarding pain and how to handle it and educate about computer network processes. The method used is by counseling and training. Counseling is carried out to increase education and understanding regarding the understanding of pain and computer network processes. While the training was conducted to train students to use medical therapy devices, namely infrared so that they can be used independently by them and training on making UTP cables with Rj45 connectors for LAN computer network data communications. There are two sessions in this activity, namely education and training on the use of infrared therapy devices as well as education and training for UTP and Rj45 cables. The activity was enthusiastically attended by students because this activity was something new for them marked by partners who hoped that there would be community service activities like this in the future. In addition, after the activity is carried out, mentoring will be held for 3 months so that the knowledge provided can be applied properly.

Elevators are the most common transportation tool in modern buildings. To satisfy the safety requirement, it is mandatory to carry out regular maintenance in a certain period of time. Among maintenance items, the determination of the traction compartment cable slippage status is one of the greatest challenges in the elevator industry, but a simple and effective method is still lacking. Currently, in a real situation, the inspection accuracy relies considerably on suitable personnel experiences, and the inspection process is also time-consuming. Accordingly, we aim to develop an automatic streaming image process model for the detection of the elevator cable slipping distance. First, the geometric shape of an ellipse is established from a captured circle image. Second, the ellipse is averaged and segmented into 360° with a predefined label as a reference point. Third, the circumference formula is applied to the calculation of the cable slipping distance. Finally, the outcome of the arithmetic operation is sent to the cloud database through a graphical user interface (GUI) on the web for monitoring purposes. The experimental results reveal that the standard deviation is as small as 1.153 mm, and the measurement uncertainty is only 0.258 mm, demonstrating high accuracy, rapidity, and robustness. [ABSTRACT FROM AUTHOR]

The increasing complexity of electrical and electronic systems in unmanned aerial vehicles (UAVs) has raised concerns regarding unwanted electromagnetic interference (EMI) due to limited compartment space. Recent studies have highlighted the UAV cabling as the primary pathway for interference. This paper presents a novel approach to investigating the effects of interference power, polarization angle, and distance from the interference source on EMI in UAV cable systems. Measurements and simulations were performed to analyze the influence of these factors on the radiation received by the cable. A linear dipole antenna, operating at a frequency of 905 MHz, served as the radiation source, while a single wire cable pair terminated with a 50-ohm resistor was employed as the victim. The findings reveal that the power transmitted by the source, the distance between the cable and the source, and the polarization angle have a significant impact on the electromagnetic interference received by the cable. Notably, a perpendicular orientation of the cable to the interference source (antenna) in the far-field yielded a reduction of up to 15 dBm in EMI. The results underscore the necessity for more sophisticated models and comprehensive measurements to fully comprehend the diverse factors affecting polarization losses in practical scenarios. [ABSTRACT FROM AUTHOR]

While called the "bedrock" and "cornerstone" of US media policy, the localism principle has been chipped away over 40 years by the Federal Communications Commission's (FCC) full throated embrace of market-based practices. Recently, however, localism has emerged as a pivotal battleground in telecommunications. Through case studies of three recent regulatory issues—local cable franchising, municipal broadband, and small cell deployment—this paper examines the role of localism in US-based cable and telecommunications policy. It coins the term "telecommunications localism" to capture the changing technological focus of media regulation, from content to infrastructure. In regulatory actions over the past decade the FCC has simultaneously acknowledged local municipalities' role in telecommunications deployment and actively worked to curtail this power through deregulation. These deregulatory actions strip municipalities of their autonomy over license negotiations and local rights of way and stymies the development and deployment of local communication systems. [ABSTRACT FROM AUTHOR]

The assessment of the health status and prediction of the lifespan of cable equipment are critical for ensuring the stability and efficiency of the power grid. This paper develops a temperature-current-capacity-life calculation model for cables, considering the fast and slow charging demands of electric vehicles (EVs). Analyses under scenarios of rapid and slow charging demands are conducted, introducing a cable health index and establishing a health status assessment framework based on this index. The framework accounts for various factors leading to cable faults, offering a comprehensive evaluation of the health status of cables with different fault rates. Building upon this, a prediction method using the Fire Hawk Optimization (FHO) Algorithm and Convolutional Neural Network (CNN) is proposed. This method enhances performance by optimizing the hyperparameters of Bidirectional Gated Recurrent Unit (BiGRU) through FHO, effectively searching and determining the optimal hyperparameter configuration. The impact of different scenarios and varying EV penetration rates on cable temperature is analyzed through case studies, facilitating the assessment and prediction of health status. [ABSTRACT FROM AUTHOR]

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Vision-based robotic picking enables automation of commissioning and sortation of disordered parts. To locate parts for grasping, state-of-the-art approaches rely on convolutional neural networks for instance segmentation in 2D images. However, this requires sufficiently large training datasets, which are expensive to capture and annotate. Therefore, training with synthetic data is promising as the data can be generated automatically. We present an approach for the cut-paste method to create synthetic images for industrial use cases. With this approach, an end-user first prepares the image generation with just a smartphone and about 20 minutes of manual effort. Then, a versatile dataset with instance segmentation labels is generated automatically. In addition, a procedure for grasp pose computation is applied to enable robotic picking based on instance segmentation. For evaluation, training data is generated for a wide range of rigid parts and deformable linear objects. Testing with real-world data and practical experiments demonstrates the effectiveness of the proposed cut-paste method for industrial applications. [ABSTRACT FROM AUTHOR]

Cable maintenance is important for cable structures such as cable-stayed and Nielsen-Lohse bridges. In the current maintenance practice, cable tension is estimated from the lower mode natural frequencies of the cable. It is theoretically possible to estimate the bending stiffness of the cable and the parameters of the dampers installed on the cable if the higher mode natural frequencies, damping factors, and mode shapes are available. Conventionally, the natural vibration characteristics of the cables are estimated manually from the acceleration Fourier spectrum. The estimation accuracy of the lower mode natural frequencies is high. However, the estimation accuracy of the higher mode natural frequencies is not high, and the estimation accuracy of damping factors and mode shapes is low irrespective of modal order. In this paper, the N4SID, one of the subspace methods, is adopted to estimate the natural vibration characteristics of the cables. The N4SID is applied to numerical and experimental results of bridge cables to investigate the estimation accuracy. The numerical investigation found that the accuracy of the natural frequencies and damping factors is high, the accuracy of mode shape is high in the cable without a damper, and the accuracy of mode shape is only high for the limited low modes and low for the other mode in the cable with a damper. The experimental investigation found that the N4SID has better accuracy than the conventional estimation method. [ABSTRACT FROM AUTHOR]