The rise of two-dimensional (2D) crystalline superconductors has opened a new frontier of investigating unconventional quantum phenomena in low dimensions. However, despite the enormous advances achieved towards understanding the underlying physics, practical device applications like sensors and detectors using 2D superconductors are still lacking. Here, we demonstrate nonreciprocal antenna devices based on atomically thin NbSe2. Reversible nonreciprocal charge transport is unveiled in 2D NbSe2 through multi-reversal antisymmetric second harmonic magnetoresistance isotherms. Based on this nonreciprocity, our NbSe2 antenna devices exhibit a reversible nonreciprocal sensitivity to externally alternating current (AC) electromagnetic waves, which is attributed to the vortex flow in asymmetric pinning potentials driven by the AC driving force. More importantly, a successful control of the nonreciprocal sensitivity of the antenna devices has been achieved by applying electromagnetic waves with different frequencies and amplitudes. The device’s response increases with increasing electromagnetic wave amplitude and exhibits prominent broadband sensing from 5 to 900 MHz.

Power cables are integral to modern urban power transmission and distribution systems. For power cable asset managers worldwide, a major challenge is how to manage effectively the expensive and vast network of cables, many of which are approaching, or have past, their design life. This study provides an in-depth review of recent research and development in cable failure analysis, condition monitoring and diagnosis, life assessment methods, fault location, and optimisation of maintenance and replacement strategies. These topics are essential to cable life cycle management (LCM), which aims to maximise the operational value of cable assets and is now being implemented in many power utility companies. The review expands on material presented at the 2015 JiCable conference and incorporates other recent publications. The review concludes that the full potential of cable condition monitoring, condition and life assessment has not fully realised. It is proposed that a combination of physics-based life modelling and statistical approaches, giving consideration to practical condition monitoring results and insulation response to in-service stress factors and short term stresses, such as water ingress, mechanical damage and imperfections left from manufacturing and installation processes, will be key to success in improved LCM of the vast amount of cable assets around the world.

Cross-bonded metal sheath connection is applied in sectioned single-core power cables to reduce or eliminate the voltages which are induced in the sheath over long distances. However, cross-bonded cables present an opportunity as well as a challenge for on-line measurement and diagnosis of cable conditions. In this paper, a methodology to identify cable faults through analysis of the sheath system currents in a cross-bonded cable system is presented. Firstly, a numerical model is established to simulate the sheath currents in cross-bonded cable systems. Secondly, analyses of several faults, which happen frequently with serious consequences, are presented on the basis of current measurement at the link cable. Simulations of normal and fault conditions are given to determine the feasibility of fault diagnosis. A case study using field data from a cable tunnel in China considering the normal condition is presented to verify the numerical model. Results in normal condition show good consistency with field data with error less than 5%. Simulation results of fault conditions show that analysis of readings from 6 current sensors can distinguish different fault types and fault positions using the method proposed. Based on the analyses, criteria are established for sheath loop fault type diagnosis.

We performed ab initio molecular dynamics simulations to study the initiation chemical reaction and subsequent decomposition mechanism of a 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowutrzitane (TEX) crystal at 2160 K.

MapReduce is a very popular parallel programming model for cloud computing platforms, and has become an effective method for processing massive data by using a cluster of computers. X-to-MapReduce (X is a program language) translator is a possible solution to help traditional programmers easily deploy an application to cloud systems through translating sequential codes to MapReduce codes. Recently, some SQLto-MapReduce translators emerge to translate SQL-like queries to MapReduce codes and have good performance in cloud systems. However, SQL-to-MapReduce translators mainly focus on SQL-like queries, but not on numerical computation. Matlab is a high-level language and interactive environment for numerical computation, visualization, and programming, which is very popular in engineering. We propose and develop a simple Matlab-to-MapReduce translator for cloud computing, called M2M, for basic numerical computations. M2M can translate a Matlab code with up to 100 commands to MapReduce code in few seconds, which may cost a proficient Hadoop MapReduce programmer some days on coding so many commands. In addition, M2M can also recognize the dependency between complex commands, which is always confusing during hand coding. We implemented M2M with evaluation for Matlab commands on a cluster. Several common commands are used in our experiments. The results show that M2M is comparable in performance with hand-coded programs.