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The forward variable area bypass injector (FVABI) is a key component of double bypass variable cycle engine (VCE) to achieve mode transition and bypass ratio adjustment. In this paper, an experimental system for FVABI was constructed based on the analysis of relevant experimental theories, and then the experiments on FVABI were carried out for a specific working state in double bypass mode of VCE and for the comparison working states with different area ratios and different back pressure ratios. The results showed that the FVABI designed in this paper meets the requirements of VCE at this working state. The analysis of the influence of area ratio and back pressure ratio on the injection coefficient showed that the first bypass valve and back pressure were effective means to control the mass flow of FVABI.

The synthetic jet actuator was applied to the nozzle jet vector control by experimental and numerical simulation methods to study fluid thrust vector control in this paper. The nozzle jet produced a steady and continuous deflection under the action of synthetic jet actuators. Through the analysis of the flow structure and control mechanism of the interaction between the synthetic jet and the nozzle jet, it was found that the force formed by the pressure gradient in the nozzle duct, the entrainment and ejection of the synthetic jet to the mainstream, and the momentum synthesis of the vertical synthetic jet were able to cause the deflection of the nozzle jet. The actuator excitation voltage can adjust synthetic jet velocity, which in turn affects the nozzle jet deflection angle.

In the duplex steelmaking process, the oxygen flow rate is suppressed to reduce the increasing rate of the temperature in the molten bath, resulting in severe dynamic conditions. To improve the mixing effect of the molten bath, a Laval nozzle structure designed for combination gas has been proposed. In this research, five types of Laval nozzle structure have been built based on the combination gas content, and both numerical simulations and experiments are performed to analyze the flow field of the supersonic jet. The axial velocity and oxygen concentration were measured in the experiment, which agreed well with the numerically simulated data. The results show that both initial axial velocity and potential core length increase with the flow rate of combination gas. Further, applying a higher N2 flow rate could improve the oxygen utilization rate at different ambient temperatures, but this issue increases the oxygen utilization rate, however, the latter can be reduced at higher ambient temperatures.

ELAV/Hu factors are conserved RNA binding proteins (RBPs) that play diverse roles in mRNA processing and regulation. The founding member, Drosophila Elav, was recognized as a vital neural factor 35 years ago. Nevertheless, little was known about its impacts on the transcriptome, and potential functional overlap with its paralogs. Building on our recent findings that neural-specific lengthened 3’ UTR isoforms are co-determined by ELAV/Hu factors, we address their impacts on splicing. While only a few splicing targets of Drosophila are known, ectopic expression of each of the three family members (Elav, Fne and Rbp9) alters hundreds of cassette exon and alternative last exon (ALE) splicing choices. Reciprocally, double mutants of elav/fne, but not elav alone, exhibit opposite effects on both classes of regulated mRNA processing events in larval CNS. While manipulation of Drosophila ELAV/Hu RBPs induces both exon skipping and inclusion, characteristic ELAV/Hu motifs are enriched only within introns flanking exons that are suppressed by ELAV/Hu factors. Moreover, the roles of ELAV/Hu factors in global promotion of distal ALE splicing are mechanistically linked to terminal 3’ UTR extensions in neurons, since both processes involve bypass of proximal polyadenylation signals linked to ELAV/Hu motifs downstream of cleavage sites. We corroborate the direct action of Elav in diverse modes of mRNA processing using RRM-dependent Elav-CLIP data from S2 cells. Finally, we provide evidence for conservation in mammalian neurons, which undergo broad programs of distal ALE and APA lengthening, linked to ELAV/Hu motifs downstream of regulated polyadenylation sites. Overall, ELAV/Hu RBPs orchestrate multiple broad programs of neuronal mRNA processing and isoform diversification in Drosophila and mammalian neurons., Author summary ELAV/Hu factors comprise a conserved family of RNA binding proteins (RBPs), many of which are enriched or restricted to neurons. This study shows that overlapping activities of Drosophila ELAV/Hu RBPs determine global patterns of neural alternative splicing, including of cassette exons and alternative last exon (ALE) isoforms. This is supported by both genetic necessity in double mutant CNS, as well as their sufficiency to drive these mRNA processing changes in a non-neuronal setting. The ability of ELAV/Hu RBPs to induce the usage of distal ALE isoforms connects to their recently described functions in global extension of 3’UTRs in neural isoforms. Evidence is provided that switching to distal alternative last exons and to terminal 3’ UTR extensions are also coordinated in mammalian neurons, and show signatures of direct regulation by ELAV/Hu RBPs.

This paper reports on the re-engineering of standard five-strand tundish designs into a five-strand asymmetric tundish, which resulted in a non-uniform rate and bias for each strand. We sought to improve the casting conditions by optimizing the liquid steel flow-field in the tundish. Both a water modelling experiment and a numerical simulation were performed to analyze the flow-field according to various diversion hole diameters and injection angles. The results showed that the average residence time decreased as the diameter of the diversion holes increased. As the injection angle was increased, the average residence time initially decreased and then increased. The liquid steel from the ladle shroud rapidly extended to the #2 and #3 strands in the original tundish, which reduced the likelihood of inclusion collision and coalescence.

ELAV/Hu factors are conserved RNA binding proteins that play diverse roles in mRNA processing and regulation. The founding member,DrosophilaElav, was recognized as a vital neural factor 35 years ago. Nevertheless, still little is known about its impacts on the transcriptome, and potential functional overlap with its paralogs. Building on our recent findings that neural-specific lengthened 3’ UTR isoforms are co-determined by ELAV/Hu factors, we address their impacts on splicing. In ectopic contexts, all three members (Elav, Fne and Rbp9) induce similar and broad changes to cassette exon and alternative last exon (ALE) splicing. Reciprocally, double mutants ofelav/fne, but notelavalone, have opposite effects on both types of mRNA processing events in the larval CNS. Accordingly, whilefnemutants are normal,fneloss strongly enhanceselavmutants with respect to neuronal differentiation. While manipulation ofDrosophilaELAV/Hu factors induces both exon skipping and inclusion, motif analysis indicates their major direct effects are to suppress cassette exon usage. Moreover, we find direct analogies in their roles in global promotion of distal ALE splicing and terminal 3’ UTR extension, since both involve local suppression of proximal polyadenylation signals via ELAV/Hu binding sites downstream of cleavage sites. Finally, we provide evidence for analogous co-implementation of distal ALE and APA lengthening programs in mammalian neurons, linked to ELAV/Hu motifs downstream of regulated polyadenylation sites. Overall, ELAV/Hu proteins orchestrate multiple conserved programs of neuronal mRNA processing by suppressing alternative exons and polyadenylation sites.

SummaryHow are diverse regulatory strategies integrated to impose appropriately patterned gene expression that underliein vivophenotypes? Here, we reveal how coordinated miRNA regulation and neural-specific alternative polyadenylation (APA) of a single locus controls complex behaviors. Our entry was the unexpected observation that deletion of Bithorax-Complex (BX-C) miRNAs converts virgin female flies into a subjective post-mated behavioral state, normally induced by seminal proteins following copulation. Strikingly, this behavioral switch is directly attributable to misregulation ofhomothorax(hth). We localize specific CNS abdominal neurons where de-repressed Hth compromises virgin behavior in BX-C miRNA mutants. Moreover, we use genome engineering to demonstrate that precise mutation ofhth3’UTR sites for BX-C miRNAs, or deletion of its neural 3’ UTR extension containing most of these sites, both induce post-mated behaviors in virgins. Thus, facilitation of miRNA-mediated repression by neural APA is required for virgin females to execute behaviors appropriate to their internal state.

The tissue-specific deployment of highly extended neural 3’ UTR isoforms, generated by alternative polyadenylation (APA), is a broad and conserved feature of metazoan genomes. However, the factors and mechanisms that control neural APA isoforms are not well-understood. Here, we show that three ELAV/Hu RNA binding proteins (Elav, Rbp9 and Fne) have similar capacities to induce a lengthened 3’ UTR landscape in an ectopic setting. These factors promote accumulation of chromatin-associated, 3’ UTR-extended, nascent transcripts, through inhibition of proximal polyadenylation site (PAS) usage. Notably, Elav represses an unannotated splice isoform of fne, switching the normally cytoplasmic Fne towards the nucleus in elav mutants. We use genomic profiling to reveal strong and broad loss of neural APA in elav/fne double mutant CNS, the first genetic background to largely abrogate this distinct APA signature. Overall, we demonstrate how regulatory interplay and functionally overlapping activities of neural ELAV/Hu RBPs drives the neural APA landscape.

For a certain type of turbofan engine, the mathematical model of the intake air humidity is established in this paper. Then the influence of intake air humidity on the cross-section parameters of the turbofan engine and the characteristics of the compressor are analyzed. In addition, we considering the influence of water vapor on combustion efficiency. The results show that: in a certain range of intake air humidity, with the increase of intake air humidity, the effect on the compressor pressure ratio is small, but the flow will have decreased. In the combustion process, it will increase fuel consumption and energy consumption. Finally, it causes the total thrust of the turbofan engine to fall and the fuel consumption rate increases.

Conformal imaging systems are confronted with dynamic aberration in optical design processing. In classical optical designs, for combination high requirements of field of view, optical speed, environmental adaption and imaging quality, further enhancements can be achieved only by the introduction of increased complexity of aberration corrector. In recent years of computational imaging, the adaptive coded apertures techniques which has several potential advantages over more traditional optical systems is particularly suitable for military infrared imaging systems. The merits of this new concept include low mass, volume and moments of inertia, potentially lower costs, graceful failure modes, steerable fields of regard with no macroscopic moving parts. Example application for conformal imaging system design where the elements of a set of binary coded aperture masks are applied are optimization designed is presented in this paper, simulation results show that the optical performance is closely related to the mask design and the reconstruction algorithm optimization. As a dynamic aberration corrector, a binary-amplitude mask located at the aperture stop is optimized to mitigate dynamic optical aberrations when the field of regard changes and allow sufficient information to be recorded by the detector for the recovery of a sharp image using digital image restoration in conformal optical system.

For the disadvantages of orthogonal wavelet transform multi-modulus blind equalization algorithm(WTMMA), such as slow convergence rate, large mean square error, and immerging in partial minimum easily, an orthogonal wavelet transform multi-modulus blind equalization algorithm based on Tabu search DNA genetic optimization algorithm(DNAGA-WTMMA) was proposed. Firstly, DNA populations were initialized by using double-stranded DNA form to select the single-stranded DNA sequences as the representative strands of individuals. Secondly, Tabu search strategy was introduced into crossover operations to avoid circuitous search, ensure the searching different paths, and escape from local optimum. Thirdly, in order to speed up the convergence rate and avoid premature convergence, the probability of crossover operation was decided by dynamic adaptive probability based on population prematurity degree index. Computer simulations show that, compared with multi-modulus blind equalization algorithm(MMA) and WTMMA, the proposed algorithm has the fastest convergence rate and the smallest mean square error. Introduction In wireless communication, blind equalization technology without sending the training sequence is one of important methods of suppressing the inter-symbol interference(ISI) caused by complicated communication channel and limited bandwidth. In the blind equalization algorithms, the constant modulus blind equalization algorithm(CMA) has good equalization performance for constant modulus signals, but it has large mean square error for high-order QAM signals. While the multi-modulus equalization algorithm(MMA) with the amplitude and phase information of output signals can reduce effectively the mean square error(MSE). Orthogonal wavelet multi-modulus blind equalization algorithm outperforms MMA in equalizing multi-modulus signals. However, the weight vector of the CMA and the MMA is updated by gradient search method, therefore, they are easy to fall into local convergence and difficult to obtain the global optimal solution[1]. Genetic algorithm(GA) has stronger robustness and global random search abilities and can find global optimal solution in complex, multi-peak large solution space. However, the traditional genetic algorithm is easy to fall into premature convergence and its convergence speed is slow[2]. DNA computing proposed by Adleman in 1994, has strong ability of parallel computing, can be used to search all potential solutions. Due to the nature connection with DNA computing and genetic algorithm, DNA computing is introduced into genetic algorithm to improve the performance of GA[3][4]5][6]. Tabu search algorithm(TS) is a global search algorithm with short-time memory, a tabu list (movements in the list were temporarily forbidden) and an aspiration criterion changing the content of tabu list are adopted[7][8]. Therefore, we introduce tabu search algorithm into DNA genetic algorithm to improve the performance of DNA genetic algorithm. Based on the above analysis, an orthogonal wavelet transform multi-modulus blind equalization algorithm based on tabu search DNA genetic optimization algorithm(DNAGA-WTMMA) is International Conference on Materials Engineering and Information Technology Applications (MEITA 2015) © 2015. The authors Published by Atlantis Press 129 proposed. This proposed algorithm uses cost function of the WTMMA as the fitness function of DNA-GA, then uses DNA-GA to solve the cost function of the equalizer to find optimal individual. Compared with multi-modulus blind equalization algorithm(MMA) and orthogonal wavelet transform multi-modulus blind equalization algorithm(WTMMA), the proposed algorithm has the fastest convergence rate and the smallest mean square error. Orthogonal Wavelet Transform Multi-modulus Blind Equalization Algorithm

Predation is a complex process among predator, prey and environment. Juvenile sea urchins are more susceptible to predators than adults, which affects community structure. Behavior is involved in anti-predator responses by changes in the expression of anti-predator responsive genes. Here, we investigated the effects of exposure to a predatory crab Charybdis japonica and covering behavior on survival and HSP70 expression of juvenile sea urchins Strongylocentrotus intermedius. C. japonica consumed large numbers of juvenile S. intermedius in 12 hours with a mortality of 34.17±11.43%. Covering behavior did not significantly reduce predation. Exposure to C. japonica did not significantly upregulate HSP70 expression of juvenile S. intermedius in 12 hours. Covering behavior showed no significant regulative effect on the gene expression of HSP70 of juvenile S. intermedius exposed to C. japonica for 12 hours. The results indicate that the anti-predator function of covering behavior is limited and that HSP70 expression does not appear to play an important role in the anti-predator process of S. intermedius.

Divergence angle of antenna is an important parameter in laser optical communication. It determines the power of the receiver terminal. In this paper, the influence of temperature on the divergence angle is discussed. Theoretical analysis and experiment results demonstrate that the relationship between the variance of temperature and of divergence angle is linear.

This paper presents a parallel image processing model based on pipeline concerning that the current efficiency of remote sensing image processing can't meet the need of processing increasing number of remote sensing data. In the multi-core CPU era, the pipeline technology can process the complex and time-consuming steps of the remote sensing image processing in parallel. This model can improve the processing efficiency significantly. The principles of the pipeline and the parallel computing are illustrated in detail in this paper. The obtained experimental results show that the parallel processing model based on pipeline is efficient in the processing of remote sensing image with large amount of data.

Random telegraph signals (RTS's) arising from interfacial defects in small accumulation-mode SOI/nMOSFETs have been studied. By analyzing the average capture time of each RTS as a function of both the front-gate and back-gate voltages, the authors are able to distinguish between defects at the front interface from those at the back interface. In contrast to the RTS's typically observed in enhancement-mode MOSFETs where only those interfacial defects within an energy range close to the Si band edge can be measured, the use of the accumulation-mode SOI/nMOSFET makes it possible to probe interface traps near midgap. >

Hot-carrier effects in enhancement-mode thin-film SOI/NMOSFET's have been studied quite extensively, but similar studies in accumulation-mode devices are still lacking. This paper will report hot-carrier effects in accumulation-mode thin-film SOI/NMOSFET's. Changes in both front- and back-channel transistor parameters are discussed. One particularly interesting effect is the increased drain-source breakdown voltage when measured in the reverse mode after hot-carrier damage. A model based on the increased hole/electron recombination rate due to hot-carrier induced back interface traps will be proposed to explain the effect. >

The Y-box protein family is highly conserved nucleic acid binding proteins which are conserved from bacteria to human.The complete cDNA of Y-box was cloned through degenerate primer PCR amplification and SmartTM Race technology.The length of the cDNA of sea urchin Y-box gene is 2 425 bp,which contains a 996bp open reading frame(ORF),a 1 348 bp 3 UTR and an 81 bp 5 UTR.The AATAA special sequences in the 3′ UTR and polyA regions were detected.The full-length Y-box cDNA encoded 331 amino acids constituting a 37.4 ku protein molecule with an isoelectric point of 8.55.The precursor protein was hydrophily.The N-glycosylation site,hydrophily C-tail end and cold shock domain CSD were evaluated.The Y-box protein family was very conservative in CSD domain.The secondary structure of the precursor protein consisted primarily of a 1.98% alpha helix,with a 9.97% strand chain and random coil 88.22%,without β folding.The comparison revealed that the similarity of the Y-box precursor protein ranged from 22.37% to 41.26% with other animals.The evolutionary tree indicated that the Y-box precursor protein of sea urchin was clustered with Aplysia californica and Chlamys farreri.The Y-box gene expression pattern was detected in coelomic fluid,tube feet,peristomial membrane,male gonad,female gonad,muscle and intestinal tissue.Tissue distribution pattern showed that the difference was not significant in sea urchin.The expression of Y-box gene under temperature stress was reduced,and the expression quantity of Y-box gene decreased gradually with the rise of temperature.The results provide reference for investigating the function of this gene.