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Despite contributions, most of the studies on electronic‐telecommunications trade are conducted within the framework of a global value chain and mainly based on an enterprise‐level. The global trade structure and dynamics of electronic‐telecommunications are still mysterious. In this paper, by deriving trade data of electronic‐telecommunications between countries (regions) from the UN Comtrade Database, characteristics in product, space and network of the global electronic‐telecommunications trade from 2000 to 2017 are explored, and the factors influencing its evolution. The results indicate that telecommunications equipment is gradually replacing electronic integrated circuits, thus leading the development of global trade on electronic‐telecommunications. In space, the global import pattern of electronic‐telecommunications has always been a tri‐polar pattern dominated by Asia‐Pacific, Europe, and North America, while the geography of global electronic‐telecommunications export has undergone fundamental changes, most notably the rise of the East Asia region represented by Mainland China. The global trade center in electronic and communication products has changed from USA to China. In terms of network structure, the global electronic‐telecommunications trade network continues to expand, showing significant small‐world and core‐peripheral characteristics, and a more competitive multi‐centric core is observed. In addition, Quadratic Assignment Procedure analysis indicates that culture proximity, innovation differences, and manufacturing differences have a positive effect on the international trade, while geographical distance, economic gap, openness gap, trade gap, and infrastructure gap play negative roles. [ABSTRACT FROM AUTHOR]

The need for high‐precision calculations with 64‐bit or 32‐bit floating‐point arithmetic for weather and climate models is questioned. Lower‐precision numbers can accelerate simulations and are increasingly supported by modern computing hardware. This paper investigates the potential of 16‐bit arithmetic when applied within a shallow water model that serves as a medium complexity weather or climate application. There are several 16‐bit number formats that can potentially be used (IEEE half precision, BFloat16, posits, integer, and fixed‐point). It is evident that a simple change to 16‐bit arithmetic will not be possible for complex weather and climate applications as it will degrade model results by intolerable rounding errors that cause a stalling of model dynamics or model instabilities. However, if the posit number format is used as an alternative to the standard floating‐point numbers, the model degradation can be significantly reduced. Furthermore, mitigation methods, such as rescaling, reordering, and mixed precision, are available to make model simulations resilient against a precision reduction. If mitigation methods are applied, 16‐bit floating‐point arithmetic can be used successfully within the shallow water model. The results show the potential of 16‐bit formats for at least parts of complex weather and climate models where rounding errors would be entirely masked by initial condition, model, or discretization error. Plain Language Summary: 64‐bit floating‐point numbers are the standard number format for scientific computing in fluid dynamics, which allows for very precise calculations with negligible rounding errors. The need for calculations at this precision level has been questioned for weather and climate models, as errors are caused primarily by insufficient observations or deficiencies of the models themselves. Reducing numerical precision can accelerate simulations and low‐precision number formats are increasingly supported by modern computers. This paper investigates the potential of low numerical precision with numbers that only use 16 bit of information, when applied within simulations of weather and climate. The different number formats are applied in a two‐dimensional oceanic or atmospheric circulation model. There are several 16‐bit number formats that can potentially be used, all of which have considerably larger rounding errors than the standard 64‐bit numbers. A simple change to 16 bits for all calculations will not be possible as it will degrade simulation results. However, if mitigation methods are applied, 16‐bit calculations can be used successfully within the applications of this paper. The results show the potential of 16‐bit number formats for at least parts of complex weather and climate models. Key Points: Posit numbers reduce rounding errors compared to floating‐point numbers, enabling reliable shallow water simulations with 16‐bit arithmeticErrors caused by 16‐bit arithmetic are reduced with critical computations in 32 bit, which can be implemented on present‐day hardware16‐ or even 8‐bit communication between processors introduces negligible errors, providing a perspective for reduced data communication [ABSTRACT FROM AUTHOR]

The article examine the geopolitical contest between the U.S. and China over technology. Topic include foreign investment and the global integration of supply chains for manufacturing and export; likes of Google and Facebook and cleared the way for indigenous giants such as Alibaba, Baidu and Tencent to capture the world's largest wired consumer market and manipulation of data and information flows, including artificial intelligence.

Background/aim Children and adolescents are prolific users of information and communication technologies ( ICT) in learning, leisure, and social communication activities. High exposure to ICT is associated with musculoskeletal injuries in adults; however, the management of ICT physical complaints in children is not well-understood. Methods An online survey of allied health professionals (occupational therapists, physiotherapists, and chiropractors) was undertaken to determine (i) the number of children and adolescents in Perth, Western Australia who accessed treatment for musculoskeletal complaints related to use of technology; (ii) the typical frequency and duration of service provision; and (iii) the nature of treatment provided. Costs associated with service provision were estimated. Results Data from 101 identified the most commonly treated musculoskeletal complaints among children and adolescents included: non-specific neck pain; thoracic postural pain disorder; non-specific low back pain; and lumbar postural pain disorder. Approximately 1445 children were treated in the previous 12 months; with one-third of chiropractors each reported treating 31+ children. Most common treatments were soft tissue release, mobilisation, flexibility and conditioning exercises, soft tissue massage and kinesio-taping. Verbal education about healthy use of technology was provided by most clinicians (88%), with some inconsistent recommendations. The estimated cost of treatment was AUD$1,057,715; of which AUD$544,886 was health system funded. Conclusions Children and adolescents received allied health treatment for a range of musculoskeletal complaints associated with ICT use. The potential long-term impacts on their health and wellbeing, and the economic burden associated with this health issue warrant the development of systematic risk reduction strategies. [ABSTRACT FROM AUTHOR]

Key frame extraction can facilitate rapid browsing and efficient video indexing in many applications. However, to be effective, key frames must preserve sufficient video content while also being compact and representative. This study proposes a syncretic key frame extraction framework that combines sparse selection (SS) and mutual information-based agglomerative hierarchical clustering (MIAHC) to generate effective video summaries. In the proposed framework, the SS algorithm is first applied to the original video sequences to obtain optimal key frames. Then, using content-loss minimisation and representativeness ranking, several candidate key frames are efficiently selected and grouped as initial clusters. A postprocessor - an improved MIAHC - subsequently performs further processing to eliminate redundant images and generate the final key frames. The proposed framework overcomes issues such as information redundancy and computational complexity that afflict conventional SS methods by first obtaining candidate key frames instead of accurate key frames. Subsequently, application of the improved MIAHC to these candidate key frames rather than the original video not only results in the generation of accurate key frames, but also reduces the computation time for clustering large videos. The results of comparative experiments conducted on two benchmark datasets verify that the performance of the proposed SS-MIAHC framework is superior to that of conventional methods. [ABSTRACT FROM AUTHOR]

The interaction topologies of swarm systems may be time varying due to the motions of agents or the failure of communication equipment. The current paper focuses on admissible consensus analysis and design problems for singular swarm systems with switching topologies. Admissible consensus analysis problems are converted into admissible ones of a reduced-order switching subsystem by the state projection on the consensus subspace and the complement consensus subspace. Furthermore, an approach to determine the consensus function is proposed by the first equivalent form. Moreover, by the Riccati equation, admissible consensus design criteria are presented, which can guarantee the scalability of singular swarm systems because they are independent of the number of agents. Finally, numerical examples are presented to check the correctness of theoretical results. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Visible range to telecom band spectral translation is accomplished using an amorphous SiC pi'n/pin wavelength selector under appropriate front and back optical light bias. Results show that background intensity works as selectors in the infrared region, shifting the sensor sensitivity. Low intensities select the near-infrared range while high intensities select the visible part according to its wavelength. Here, the optical gain is very high in the infrared/red range, decreases in the green range, stays close to one in the blue region and strongly decreases in the near-UV range. The transfer characteristics effects due to changes in steady state light intensity and wavelength backgrounds are presented. The relationship between the optical inputs and the output signal is established. A capacitive optoelectronic model is presented and tested using the experimental results. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Antenna arrays equipped with space-time adaptive processors (STAPs) are effective to maintain the integrity and functionality of global navigation satellite systems (GNSSs) in various applications. However, one of the major problems with existing space-time processing methods is that they can introduce significant biases into the GNSS receiver measurements. A distortionless STAP is proposed. It could not only suppress the interfering signals and enhance the GNSS signals, but also introduce no biases into the code and carrier phase measurements. The key idea behind the proposed method is ensuring linearity of the space-time processor response by constraining its coefficients. The effectiveness of the proposed method is verified by theoretical analysis and simulation results. [ABSTRACT FROM AUTHOR]