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Secure and reliable electricity supply is a prerequisite for the development of smart cities, and the trustworthy and efficient transmission of electrical data is the foundation for the safe and stable operation of the power grid. This paper introduces a real‐time data transmission blockchain technique based on parallel proof of work algorithm. The new block generation process of proposed blockchain is divided into five subroutines: hash pointer computation, real‐time data pudding, signature value iteration, interruption, block header assembly. The real‐time data pudding and signature value iteration are parallel processed, which brings the effect of decreasing energy loss of blockchain system, and enhances the speed of new block generation and the bandwidth of data storage on blockchain. Computer simulation shows the proposed strategy can be effectively applied in real‐time electrical data transmission application, raising the data transmission reliability with no harm to real‐time data transfer function. This strategy provides a solution to guarantee data transmission safety in the digital conversion of power grid. [ABSTRACT FROM AUTHOR]

ABSTRACT The design of a compact wideband the letter with U-shape shorted step-impedance-resonator (SIR) using low temperature cofired ceramic technology is introduced in this article. The filter is composed of the four shorted SIRs embedded in multilayer thin ceramic to produced a compact size. By introducing the proper coupling structure, the filter has sharp skirt characteristic. The filter is demonstrated with experimental results operating at central frequency 1.80 GHz with a 3-dB bandwidth of 75.0%. More than 30 dB of suppression from 0.5 to 1.4 GHz and more than 25 dB attenuation at 3.10 GHz are obtained in the experimental results. © 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:1145-1147, 2017 [ABSTRACT FROM AUTHOR]

An efficient approach is developed to analytically evaluate solute transport in a horizontal, divergent radial flow field with a multistep injection flow rate and an arbitrary Input concentration history. By assuming a piecewise steady state flow and transforming the time domain to the cumulative injected flow domain, the concentration distribution is found to be completely determined by the total volume of injected flow and independent of specific flow rates. Thus, on the cumulative flow domain, the transport problem with a temporally varying velocity field can be transformed into a steady state flow problem. Linear convolution can then be applied on the cumulative injected flow domain to evaluate the solution for an arbitrarily time-dependent input concentration. Solutions on the regular time domain can be conveniently obtained by mapping the solution on the cumulative injected flow domain to the time domain. Furthermore, we theoretically examine the conditions for the assumption of piecewise steady state flow to be valid. On the basis of the critical time scale of the "pseudosteady state condition," defined as when velocity changes accomplish 99% of their steady state differences, and the relative error in the mean travel time of plume front, we obtain conditions for neglecting the transitional period between two pumping steps. Such conditions include the following: (1) the duration of a pumping step, t,,, must be longer than the critical time scale, tc, i.e., tp ⩾ tc= 25r2S/T, where r is the radial distance, S is the storage coefficient, and T is the transmissivity, or similarly, a maximum problem domain needs to be defined for a given pumping strategy. (2) the maximum well pumping rate, qmax should satisfy qmax ¶OT/25S, where O is the effective porosity. When both conditions are satisfied, transitional periods may be neglected. [ABSTRACT FROM AUTHOR]

• A single-copy 5.7 kilobase (kb) DNA fragment, termed Linum Insertion Sequence 1 (LIS-1), has been identified and characterized. This is one of the DNA changes associated with the environmentally induced heritable changes resulting in stable lines termed genotrophs in flax (Linum usitatissimum).• The insertion sequence and its insertion site have been cloned from genomic libraries and sequenced. PCR products across the insertion and surrounding regions have also been cloned and sequenced.• The 5.7 kb DNA fragment is inserted into a 3.7 kbEcoRI fragment in the plastic line (Pl) with the generation of a 3 base pair duplication at the insertion site, as well as additional sequence changes. The identical insertion was also found in other genotrophs and flax varieties. The intact element was not present in Pl but appeared to be generated by a reproducible series of complex rearrangements or insertion events.• LIS-1 is the result of a targeted, highly specific, complex insertion event that occurs during the formation of some of the genotrophs, and occurs naturally in many flax and linseed varieties. [ABSTRACT FROM AUTHOR]

An asymmetrical hybrid-controlled half-bridge LCC resonant converter which integrated a buck–boost converter and a half-bridge LCC resonant converter is proposed. It benefits with wide soft switching range, low conduction loss and high power density. By utilising an asymmetrical hybrid control strategy, its switching frequency and duty ratio can be adjusted simultaneously. The proposed LCC resonant converter maintains output voltage regulation and zero-voltage switching of switches in wide input voltage and load variation range. Experiment results of a 500 W prototype are provided to verify the theoretical analysis results. [ABSTRACT FROM AUTHOR]

Variable frequency controlled LCC resonant converter suffers from wide variation of switching frequency. Although fixed frequency controlled LCC resonant converter benefits from constant switching frequency, it suffers from narrow zero voltage switching (ZVS) range of power switch and high circulating energy. A pulse width modulation-pulse frequency modulation (PWM-PFM) hybrid controlled LCC resonant converter is proposed to achieve wide ZVS range of power switch with narrow variation of switching frequency. Experiment results of a 500 W prototype are provided to verify theoretical analysis of the proposed converter. [ABSTRACT FROM AUTHOR]