Broken Cables Research Articles

Versatile Corporate Systems and Smart Devices-Based Framework to Locate Faults and Broken Cables in Power Distribution Networks

Versatile Corporate Systems and Smart Devices-Based Framework to Locate Faults and Broken Cables in Power Distribution Networks

Influence of breakages of cable groups on strength ofrubber-cable tractive-transporting element

Purpose. Development and justification of a method of analytical determination of a stress-strain state of a flat rubber-cable tractive-transporting element with breakages of continuity of cable groups in different cross-sections. Methodology of research is in development of a mathematical model of interaction of tractive-transporting element parts considering breakages of groups of random cables, construction of analytical solutions for determining dependencies of force distribution between cables and shear stresses in an elastic shell of a tractive-transporting element with random locations of breakages of cable groups in different cross-sections. Findings. A model of a flat rubber-cable tractive-transporting element with random locations of breakages of cable groups in different cross-sections is developed. Expressions that allow determining a stress-strain state of a flat rubber-cable tractive-transporting element of a hoisting and transporting machine with random locations of breakages of cable groups in different cross-sections are obtained analytically in a closed form. Strength conditions are formulated. Scientific novelty is in establishment of dependencies of interaction of disturbance fields of a stress-strain state of a rubber-cable tractive-transporting element with breakages of continuity of random cable groups in different cross-sections. It is established that disturbance fields caused by breakages of adjacent cables overlap when the breakages are located in one cross-section and there are less than three whole cables located between the broken cables. Disturbance fields also overlap when the same cable or the adjacent cable is broken in both cross-sections and the distance between cross-sections of breakage does not exceed the value, which depends on the design of a flat rubber-cable tractive-transporting element and mechanical properties of its components. Practical significance. The obtained algorithms and strength conditions allow determining a stress-strain state and preventing the breakage of the entire flat rubber-cable tractive-transporting element with breakages of cable groups in different cross-sections. These cross-sections can be: cross-section of the edge of a butt joint, where cables have breakages of continuity; cross-section, which includes the edge of an area of partial restoration of a tractive ability of the element, lost due to breakage of a cable; cross-section of cable or cable group breakage during operation. A possibility of establishing a stress-strain state and the strength conditions of a tractive-transporting element under such conditions allows reasonable determination of a possibility of its further operation in a hoisting and transporting machine.

Linear Displacement Calibration System Integrated with a Novel Auto-Alignment Module for Optical Axes

The quality of processed workpieces is affected directly by the precision of the linear stage. Therefore, the linear displacement calibration of machine tools must be implemented before delivery and after employment for a period of time. How to perform a precise calibration with high inspection efficiency is a critical issue in the precision mechanical engineering industry. In this study, the self-developed system integrated by the measurement module based on the common path Fabry–Pérot interferometer for linear displacement and the auto-alignment module for optical axes was proposed to realize the automatic linear displacement calibration of the linear stages. The measurement performance of the developed structure was verified experimentally. With the auto-alignment module, the cosine error was reduced to 0.36 nm and the entire procedure accomplished within 75 s without the limitation of the perceived resolution of the human eye, operational experience, and the risk of misalignment and broken cable. According to the comparison of experimental results for the linear displacement, the repeatability of the proposed measurement module was less than 0.171 μm. After the compensation procedure according to the linear displacement calibration, the systematic positional deviation, repeatability, and accuracy of the linear axis could be improved to 4 μm, 1 μm, and 5 μm respectively. Hence, the calibration efficiency can be improved by 80% with the proposed compact system, which is beneficial for the linear displacement calibration of machine tools in the precision mechanical engineering industry.

The Primitive Cable Car (VARANGEL) Accident-Related Fatalities: Retrospective Autopsy Study

Background The primitive cable car is the generic name given to the cable transportation settings driven between one or more steel cables is known as 'varangel.' In this retrospective autopsy study, it was aimed to discuss the common injury patterns of the fatalities associated with the use of these primitive cable car systems. Methods It is a retrospective archive-based study. The analysis of autopsy records of 10-year period between 2007 and 2016 revealed eight death cases resulting from the primitive cable car accident. Results It was revealed that the primitive cable car-related deaths mainly occur because of blunt traumas (crash of cage, chit by the broken cables, and failing from height) and electric shock. The blunt traumas and failings from height occur because of contact with the cage of primitive cable car, whereas the electric shocks occur because of contact with cables, on which the cage is hung. Conclusion Primitive cable cars may be fatal and must be under official control.

Determination of Metal Hazard in the Processed E-Waste Types, Floor Dust and Pulverized Epoxy Powder Generated at an E-Waste Handling Site in India

At the e-waste handling site, the obsolete electronic items are dismantled and it releases dust laden with fine metallic fragments, called as floor dust. Further, the broken cables are denuded from its plastic insulation and shredded to fine grained pulverized epoxy powder. These two-processed e-wastes appear to contain metal residues. Hence, the aim is to examine the metal composition and identify the hazard, if any. Pulverized epoxy powder measured high values of Cd (7.43±0.48 μg/g), Pb (338.85±0.13 μg/g), Ni (534.62±53.68 μg/g), Li (30.12±0.02 μg/g), K (508109.90±31605.89 μg/g), Ca (817395.40±2.52 μg/g) and Na (3528.00±539.07 μg/g) while floor dust had high levels of Cr (39.61±5.78 μg/g), Cu (4778.14±861.91 μg/g), Zn (4172.88±821.75 μg/g), Fe (11164.90±1111.61 μg/g) and Se (1613.00±259.04 μg/g) with significant differences (p<0.05). The worn out electronic oddments attributes to high levels of metals. Principal component analysis could extract two components accounting for 78% variance in total. Although the values are less in comparison with the statutory limits, the processed e-wastes still pose a risk of metal toxicity due to their high volume. The composition of metals in the processed e-wastes presents us a new challenge to handle them.

Stress-Strain State of a Flat Tractive-Bearing Element of a Lifting and Transporting Machine at Operational Changes of its Parameters

Main indicators of a stress-strain state of a rubber-cable belt, the rubber-cable rope for a random placement pattern and the size of the part with broken cables, including partially removed cables, with cable breakages and their random amount, different conditions of belt interaction in its cross-sections of connection to structural elements of a conveyor and a lifting machine to ensure control of its tractive ability during the life cycle. Performed researches clarify the idea of the interaction mechanism of reinforcing elements in composite materials of layered structure with hard and soft layers. Obtained results can be used for development and justification of a unified technology of creation and engineering support of operation of lifting and transporting machines with flat tractive-bearing elements with increased life-span, level of efficiency and operational safety in systems of extraction, transportation and processing of minerals.

R101 Airship Disaster and the Broken Elevator Cable

HMA R101 came down and was destroyed by fire near to Beauvais, France, with only six survivors, and the disaster ended British involvement in the development of large airships. The conclusions reached by the subsequent Court of Inquiry left some doubt regarding the cause of the crash, and consequently several alternative theories have, from time to time, been published. None have discussed the possible role of the broken elevator cable, largely because the Court of Inquiry concluded that it was irrelevant. The possibility that the broken cable may have been responsible for the disaster is examined here and it is shown that it fits rather well with the physical evidence from the wreck, and computer modelling of the crash confirms that it gives a simpler and more plausible explanation of the disaster. The reasons why the Court of Inquiry rejected it, believing that the cable broke after the crash, are discussed.

Distributed intrusion monitoring system with fiber link backup and on-line fault diagnosis functions

A novel multi-channel distributed optical fiber intrusion monitoring system with smart fiber link backup and on-line fault diagnosis functions was proposed. A 1×N optical switch was intelligently controlled by a peripheral interface controller (PIC) to expand the fiber link from one channel to several ones to lower the cost of the long or ultra-long distance intrusion monitoring system and also to strengthen the intelligent monitoring link backup function. At the same time, a sliding window auto-correlation method was presented to identify and locate the broken or fault point of the cable. The experimental results showed that the proposed multi-channel system performed well especially whenever any a broken cable was detected. It could locate the broken or fault point by itself accurately and switch to its backup sensing link immediately to ensure the security system to operate stably without a minute idling. And it was successfully applied in a field test for security monitoring of the 220-km-length national borderline in China.

An overview on the use of satellite communications for disaster management and emergency response

In disaster situations, communication is vital to organise and coordinate Search and Rescue (SAR) operations. In some disasters it may not be possible to use the existing terrestrial communication network due to damaged infrastructure, broken cables and/or energy sources, overload on the network, or non–existing communication network. To overcome the damaged/congested network problem and support the SAR activities to mitigate effects of the disaster, satellite communication is used, since it provides a robust, reliable, flexible, easy to deploy capacity, high bandwidth, and a long coverage range. This paper is an overview of the use of satellite communications for the disaster management and emergency response. This paper is intended to be a general resource and capacity building for the disaster managers and responders.

Debris From Cobalt-Chrome Cable May Cause Acetabular Loosening

To address the issue of nonunion with trochanteric osteotomy, surgeons have experimented with various modes of fixation, wire and cable being the two most popular. From a group of 643 primary cemented total hip arthroplasties performed by a single surgeon via the trans-trochanteric approach, minimum four-year roentgenographic follow-up evaluations were performed on 322 hips (50%). The method of fixation was stainless steel monofilament wire in 162 cases and Co-Cr cable in 160. Trochanteric union rates were 75% (122 patients) for the wire group and 79% (126 patients) for the cable. Breakage rates of the entire trochanteric fixation construction (all three wires or cables) were 43% (68 patients) for the wire and 12% (20 patients) for the cable. Unraveled cable was seen in 56% of the hips (90 patients), and in 47% of these hips, there were no broken cables. Blinded roentgenographic analysis of the acetabulum, preformed independently, revealed that loosening of the acetabulum in the cable group was greater than in the wire group. Cables offer no significant benefit over wires and may have potential adverse effects. Generation of significant particulate debris was noted roentgenographically, and marked reaction/destruction was found at the time of revision surgery.

The Cable Repair Ship H.M.T.S. Monarch

IN connexion with ‘Telephone Week’ (October 1-6), members of the general public had an opportunity of inspecting the Post Office cable repair ship Monarch, which was lying in the Thames off the Tower. This ship is fitted out with the special gear necessary for carrying out all the operations required in cable laying and repair, on which service she is at sea for most of the year attending to cables such as those laid between Great Britain and the Continent. The positions of cables are charted so that a faulty section or broken cable may be located and raised by means of grappling gear, of which there are various types provided. The ship's testing laboratory contains apparatus for the measurement of conductor resistance, insulation resistance, localisation of faults and other tests applied to the end of a cable which has been hauled on board. Sections of defective cables are replaced by lengths of new cable, a supply of which is carried in the ship, and the repaired cable relaid and charted, a somewhat noticeable feature of the cross Channel cables being the large number of repairs marked on the charts. The ship is provided with wireless equipment including a valve trans mitter and, in reserve, a quenched-spark transmitter. In addition to an ordinary receiver there are a directional receiver and an emergency automatic call which rings an alarm bell, when the operator is not on watch, as soon as it responds to three ‘longs’, of four seconds duration, out of the twelve sent for the SOS signal. The chart house contains an echo sounding device. The ship's complement is 14 officers and 50 ratings, this large number being required on account of the technical duties, in ad dition to ordinary duties, carried out on board.