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Background: The Recovery Self-Assessment (RSA) is a popular and well-validated instrument for assessing recovery-oriented service around the world. Aims: This study aims to develop a Chinese version of the RSA, which assesses the recovery orientation of hospital-based mental health services. Methods: We conducted forward and backward translations of the RSA and modify the translated Chinese based on comments by content experts. We recruited 350 people with mental illnesses who regularly attend hospital and community mental health services. The participants completed the Chinese Recovery Self-Assessment Service User version (CRSA-SU) and convergent measures on hope and mental well-being. Results: The Rasch analysis supported five of the six factors in the instrument and suggests that the "Life Goal" factor could be further split into two factors. We identified three misfit items (items 6, 12 and 17) that could be considered for removal. Both the internal consistency and test-retest reliability are between satisfactory and very good within each subscale, with the exception of the Choice subscale. The seven subscales had low positive correlations with measures of hope and mental well-being, which supported the convergent validity of CRSA-SU. Conclusions: The results supported the factor structure, reliability and validity of the CRSA-SU. [ABSTRACT FROM AUTHOR]

Three-phase three-core distribution power cables are widely deployed in power distribution networks and are continually being extended to address the ever-increasing power demand in modern metropolises. Unfortunately, there are high risks for the repair crew to operate on energized distribution power cables, which can cause deadly consequences such as electrocution and explosion. The predominant energization-status identification techniques used today are either destructive or only applicable to un-shielded power cables. Moreover, the background interferences affect the sensing technique reliability. In this paper, we have developed a non-destructive energization-status identification technique to identify energized three-phase three-core distribution power cables by measuring magnetic fields around the cable surface. The analysis shows that the magnetic-field-distribution pattern as a function of azimuth around the cable surface of the energized (current- or voltage-energized) three-phase three-core distribution power cable is distinguishable from the de-energized one. The non-idealities of phase currents and cable geometry were also discussed, and the proposed method still works under these circumstances. The sensing platform for implementing this technique was developed accordingly, consisting of magnetoresistive sensors, a triple-layered magnetic shielding, and a data acquisition system. The technique was demonstrated on a 22-kV three-phase three-core distribution power cable, and the energized status of the cable can be successfully identified. The proposed technique does not damage cable integrity by piercing the cable, or exposing the repair crew to hazardous high-voltage conductors. The platform is easy to operate and it can significantly improve the situational awareness for the repair crew, and enhance the stability of power distribution networks. [ABSTRACT FROM PUBLISHER]

Current monitoring can facilitate preemptive action in electrical distribution network, so as to relieve power congestion, improve transmission efficiency, and ensure network reliability. The non-invasive current sensing devices are promising since they do not require contacting hazardous high voltage and their installation is much easier compared with invasive current sensing devices. However, the existing non-invasive current sensing devices, such as current clamps and Rogowski coils are only applicable for measuring single-core underground power cables. In this paper, we established a non-invasive technique, that can monitor the currents of a multi-core underground power cable by measuring the emitted magnetic field around the cable surface. The additional magnetic fields generated by induced and leakage currents on the cables were firstly evaluated. Magnetoresistive (MR) sensors in a circular array were adopted to measure magnetic field around the cable surface, and a triple-layer shielding was designed to reduce the effects of external interference. Regarding intrinsic noise in MR sensors (e.g., 1/f noise and thermal noise), magnetic flux concentrators were supplemented to improve the signal-to-noise ratio. The developed platform was tested in a substation, and the reconstructed results closely matched the real geometrical configuration and current records of the tested cable. Apart from the non-invasive feature, the platform also shows great potential to improve the sensing capability of current amplitude and frequency compared with CTs by adopting MR sensors. [ABSTRACT FROM PUBLISHER]

Adopting non-contact capacitive coupling for voltage monitoring is promising as it avoids electrical connection with high-voltage transmission lines. However, coupled voltage transformation matrix to correlate voltage of overhead transmission lines and induction bars has not been achieved mathematically due to the lack of equivalent electric circuit model for analyzing the physical phenomenon. Moreover, exact spatial positions of overhead transmission lines are typically unknown and dynamic in practice. In this paper, a technique based on non-contact capacitive-coupling and assisted by magnetic-field sensing for monitoring voltage of overhead transmission lines was designed and implemented. The technique in this paper is demonstrated on a single-circuit transmission line as an example, while it is also applicable for multi-circuit transmission lines. The capacitive coupling between overhead transmission lines and induction bars were modeled as lumped capacitors, and then, the equivalent electric circuit model was established. The coupled voltage transformation matrix to correlate voltage of overhead transmission lines and induced voltage of induction bars mathematically was formed accordingly. This paper was also carried out to analyze the effect of ground wires, sensitivity of induction bars, the ability of high-frequency transient measurement, and the intrinsic capacitance of a measurement instrument. The exact spatial positions of overhead transmission lines were acquired by integrating magnetic-field sensing with the stochastic optimization algorithm. The methodology was verified by simulation on the 10-kV single-circuit three-phase overhead transmission lines taking non-ideality of signal measurement in account, and wavelet de-noising algorithm was supplemented to filter the interferences. A scaled testbed to experiment the technique was built to monitor 220 V overhead transmission lines in the lab, and also the typical waveform of a high-frequency switching surge (up to 1 kHz), which was generated by a programmable ac source. The reconstructed results match well with the actual values. This technique can largely improve transient-fault identification over traditional potential transformers by the virtue of the increased upper measurement limit and bandwidth through capacitive coupling. Moreover, it can be implemented with low-cost copper induction bars and compact magnetoresistive sensors, enabling large-scale application to realize sectional monitoring in the wide area. [ABSTRACT FROM PUBLISHER]

In this paper, a novel technique based on magnetic field sensing is proposed for underground power cable detection and inspection. In this technique, the current sources of the underground power cables are reconstructed based on a set of measured magnetic field values at the ground surface level emanated by the electric currents carried by the underground power cables. The stochastic optimization technique developed with an artificial immune system algorithm is applied to realize the reconstruction. The principle of this method was proved and verified experimentally by our laboratory setup. Application of this method was demonstrated on the simulation models of 11- and 132-kV underground power cables. The reconstruction results of the electrical and spatial parameters of the cables match accurately with the actual source parameters of the cables in the models. This paper shows that the proposed method is able to remotely detect the horizontal locations and vertical depths of underground power cables with high accuracy at the ground surface level requiring no prior knowledge about the exact locations of the cables. Thus, it can be potentially used to develop a portable locator for providing a map of the underground electrical cables by simultaneous detection of multiple power lines. This method can also enable engineers to correctly inspect the operation states of the target cables during onsite maintenance. This technique is applicable to various laying conditions and cable configurations (three core or single core) of the underground power cables. In addition, this is an entirely passive method and does not need any signal injection into the cables. [ABSTRACT FROM PUBLISHER]

In this paper, a novel nondestructive method based on magnetic field sensing is proposed for underground power cable operation-state monitoring and energization-status identification. The magnetic field distribution of the cable is studied using finite element method (FEM) for the power cable operating in different states, i.e., current-energized state (the cable is energized and carries load current) and voltage-energized state (the cable is energized but carries no load current). This innovative method can reconstruct all the source parameters of the cable based on a set of measured magnetic field values. Stochastic optimization technique is applied to realize the reconstruction based on the measured magnetic field. The technology is developed with an artificial immune system algorithm that is able to find out the global optimum with high probability even if very little knowledge about objective function is provided. Application of this method is demonstrated on an 11 kV cable with metallic outer sheath. The results highly match with the actual source parameters of the cable. For application in practice, possible limitations introduced by the nonidealistic of magnetoresistive sensor on magnetic field measurement are discussed and corresponding solutions are suggested. An experimental setup is constructed and the test results are used for the demonstration of this method. This paper shows that the proposed method is able to monitor the operation states of an underground power cable with high accuracy. Engineers can also correctly identify the energization status of the target cable during onsite maintenance. This method is adaptable to other kinds of power cables simply by updating the geometrical and material parameters of the cable in the FEM computation. Moreover, this is an entirely passive method and does not need any active signal injection into the cable. [ABSTRACT FROM PUBLISHER]