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This study proposes a tensegrity-based traction structure with D-bar dual cable units. It is used to connect the airship and the ground to stabilize the airship.

The mathematical models and dynamic models of the D-bar dual cable (hereafter referred to as DD cable) unit of the tensegrity-based traction structure are established. Based on the minimum mass method, the mass of the DD cable unit in the critical state (cable member is yielding, or bar member is buckling or yielding) is analyzed. Then, the tensile strength of the DD cable unit and single cable unit under the same condition is compared using the control variate method. Finally, based on ANSYS dynamic simulation, the stability of the two structures under the same external force disturbance was tested.

Expressions for the minimum mass of the DD cable unit under different failure conditions are solved. Dynamic simulation results show that the capacity of resisting disturbance of the DD cable unit is much better than that of the single cable unit under the same wind speed. So, we find a structure more suitable for the fixed connection of an airship.

This study helps to provide theoretical reference and thinking for the practical application of the traction structure with a D-bar dual cable unit.

In this paper, modeling of the XLPE cable for electromagnetic signature study at a far distance is proposed. The paper aims to discuss these issues.

Due to the very small ratio of the dimensions of cables to the dimensions of the whole system, using actual geometry of the cables with all layers in this study causes deformation of the cable's model. Therefore, multi-dipole modeling is used for modeling the cables.

This model includes specific voltages and currents in lines and nodes, respectively. Radiated electric and magnetic fields at a far distance are selected as the index of appropriateness of the model.

In order to investigate the accuracy of the model, various configuration of the cable is studied. Additionally, coupling of the cable with an electrical machine is investigated. They all show that the equivalent models can be used in place of the actual model for signature studies.

The purpose of this paper is to propose the optimal allocation and alignment of probes for current distribution measurement (CDM) in the case of twin cable in conduit conductor (CICC) cables with equal and opposite current.

The most effective approach to CDM in CICC cables is to perform indirect measurements starting from magnetic field map measured externally to the cable. A number of approaches have been proposed to optimize the layout of magnetic field probes external to the cable, but all dealing with single cables. In this paper, an approach to the optimized design of measurement system for twin cables will be proposed, based on the minimization of a suitable cost function.

A method for the optimal allocation of probes both in terms of rejection of the background field and of condition number of the Green matrix has been defined.

The method is valid only in the hypothesis of linear relationship between currents and magnetic field.

The proposed approach allows to design more robust CDM systems, with increased noise and background field rejection capability.

The problem of optimal design of CDM systems has been previously tackled in literature, but typically with reference to single cables. In the paper, an approach able to explicitly deal with twin cables is proposed.

Underground cables can produce higher electromagnetic fields directly above them than an overhead line. The majority of cable failures on distribution system are caused by defects in the cable accessories. Nowadays, significant research has been carried out worldwide into examining whether electricity, and in particular, the presence of electric and magnetic fields have an adverse impact on health, especially the occurrence of cancer and childhood leukemia. The purpose of this paper is to optimize the electric field distribution in underground cable accessories. This reduces the impact of the harmful effects of the fields on living beings and humans.

Cable terminations and joints are designed to eliminate the stress concentration at the termination screen to avoid the breakdown of the cable and high values of electric field at these points. Any improvement in the cable termination and joints construction is of great interest. There are several methods for the solution of electric field distribution. These can be summarized as analytical, experimental, free-hand field mapping, analogue methods and numerical methods. In this paper cable accessories are modeled by using multilayer dielectric system and very thin deflector’s cones.

This model includes specific insulators design and smart choice of electrodes position. Stress-grading nonlinear materials in form of tapes and tubes were used with much success. In order to optimize the cable joint parameters, two criteria were monitored – total electric field magnitude and magnitude of the tangential component. More than 30 percent is reduced impact of cables on the environment.

In order to investigate the accuracy of the applied numerical model, various configurations of the cable accessories are studied. The first time is applied new Hybrid Boundary Elements Method on the protection of the environment.

This paper aims to determine the effect of exposure of underground electrical cables to chemically contaminated water.

Visual inspection and photography were carried out to record the appearance of electrical cables. Failed and un-failed cable samples were collected and analyzed using light microscopy, scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy. Sand and water samples were chemically tested for contaminants.

Underground low-voltage 0.6/1-kV cross-linked polyethene insulated cables belonging to a chemical production plant suffered failure after four years of service. Excavation of the cable trench revealed that the cables were buried in sand polluted with chemically contaminated water. The cables were discolored and covered with corrosion deposits. Experimental results indicated that the cable insulation was heavily degraded and the outer jacket of polyvinyl chloride exhibited cracks that had penetrated through its thickness. Water and sand surrounding the cable were found to have high concentrations of ammonia. Mechanical testing of the cables indicated high values of stiffness that could contribute to the formation of cracks at the surface.

It was concluded that contamination in the water had degraded the cable, resulting in the development of a network of branched cracks within the cable insulation through which water could permeate, leading to eventual failure of the cable. Accelerated degradation took place due to exposure to the contaminated environment, which promoted aging and brittleness. Continued exposure of electric cables to contamination would lead to power failures and plant shutdowns.

This paper provides an account of a failure investigation of low-voltage electrical cable buried underground. It discusses the role of contaminated environment in the eventual failure of electrical cable due to corrosion. This information will be useful for plant engineers and project managers working in any industry that makes use of chemicals.

In order to replace the conventional human maintenance of cable‐stayed bridges, a robot is designed and constructed for tasks such as cleaning, painting and rust‐detecting.

Adopting a modular approach, two kinds of climbing mechanisms, plus a painting mechanism and a rust‐detecting method are designed.

A robot that can climb and maintain the cables of cable‐stayed bridges has been designed and constructed. It has been proved by experiment that the robot can overcome many disadvantages of conventional human bridge‐maintenance, and drastically improve efficiency, cost, and safety.

The robot is of industrial size, but a new mechanism requiring less installing time will be designed for the future.

The robot has been applied to cables of the Nanpu Bridge and Xupu Bridge in Shanghai. More than 80 cable‐stayed bridges and six suspension bridges have been built or are being constructed across large rivers in China alone. This gives an enormous potential market.

The cable maintenance robot developed in this paper is the world's first special robot for the cables of cable‐stayed bridges.

This paper aims to obtain the further and overall generation about the static characteristics of the structure for the better application of the structure.

Through nonlinear finite element simulation, serials of comparative analyses are performed on this structure and other three assumed structures, which illustrate the effect of the main part of the structure on the structural static properties. Meanwhile, adopting the first order method, spatial cable force optimization makes the structural mechanic more rational.

Under same level stress, this three‐main‐truss and three‐cable‐plane bridge could save almost 38.8 percent vertical chords materials consumption at least. In contrast, this bridge has a lower lateral torsional stiffness, considering the key to raise the lateral and torsional stiffness is enhancing axial stiffness of plane bracing, the suitable plane bracing members area is twice as the original area. After rational optimization, the cable tension ratio between the mid‐cable plane and the two side‐cable planes ranges from 1.09 to 1.14.

The work in this paper of the comparative analysis could give other engineers a way to a deep analysis method for the structural analysis, especially in civil engineering. The conclusions would provide other designers some applied advice.

With proposals being made in this country for the development of cable TV, perceptive retailers will not have failed to see the opportunities it opens up to them. In America, currently 55% of all homes are passed by a cable link, and some 34% connected. But the vast majority of these are one‐way, which is limiting. In March RMDP held a conference on “Cable TV and the Retailer” which explored the ways in which cable TV might impact on the retailer, looking at developments in the United States and in Europe. RDM was at the conference.

This article describes the design and application of underwater cable location systems.

THE Spacelab Scientific (CPSE) Airlock is equipped with an experiment table to transfer experiments from the Module into space environment. In the table drive system multi‐stranded steel cable is used, running over small‐diameter pulleys. For cleanliness requirements the original cable lubricant was replaced by a fluorinated fluid. Cable cleaning and relubrication methods have been established. The coating thickness can be chosen. Tests were run with and without lubrication. The cables were tested at ESTL on a test rig, based upon the experiment table design, in a thermal vacuum test. The performance has been improved by: • a more flexible cable • increase of lubricant thickness • decrease of contact stresses Testing in air has been included as it appeared to be an aggressive environment, where a failure occurred.