An improved spline-local mean decomposition and its application to vibration analysis of rotating machinery with rub-impact fault

A troublesome problem in application of local mean decomposition (LMD) is that the moving averaging process is time-consuming and inaccurate in processing the mechanical vibration signals. An improved spline-LMD (SLMD) method is proposed to solve this problem. The proposed method uses the cubic spline interpolation to compute the upper and lower envelopes of a signal, and then the local mean and envelope estimate functions can be derived using the envelopes. Meanwhile, a signal extending approach based on self-adaptive waveform matching technique is applied to extend the raw signal and overcome the boundary distortion resulting from the process of computing the upper and lower envelopes. Subsequently, this paper compares SLMD with LMD in four aspects through a simulative signal. The comparative results illustrate that SLMD consumes less computation time and produces more accurate decomposed results than LMD. In the experimental part, SLMD and LMD are respectively applied to analyze the vibration signals resulting from a rotor-bearing system with rub-impact fault. The results show that SLMD can more efficiently and accurately extract the important fault features, which demonstrates that SLMD performs better than LMD in analyzing the mechanical vibration signals

CUEING: a lightweight model to Capture hUman attEntion In driviNG

Discrepancies in decision-making between Autonomous Driving Systems (ADS) and human drivers underscore the need for intuitive human gaze predictors to bridge this gap, thereby improving user trust and experience. Existing gaze datasets, despite their value, suffer from noise that hampers effective training. Furthermore, current gaze prediction models exhibit inconsistency across diverse scenarios and demand substantial computational resources, restricting their on-board deployment in autonomous vehicles. We propose a novel adaptive cleansing technique for purging noise from existing gaze datasets, coupled with a robust, lightweight convolutional self-attention gaze prediction model. Our approach not only significantly enhances model generalizability and performance by up to 12.13% but also ensures a remarkable reduction in model complexity by up to 98.2% compared to the state-of-the art, making in-vehicle deployment feasible to augment ADS decision visualization and performance

Rapid subsurface damage detection of SiC using inductivity coupled plasma

This paper proposes a method for the rapid detection of subsurface damage (SSD) of SiC using atmospheric inductivity coupled plasma. As a plasma etching method operated at ambient pressure with no bias voltage, this method does not introduce any new SSD to the substrate. Plasma diagnosis and simulation are used to optimize the detection operation. Assisted by an SiC cover, a taper can be etched on the substrate with a high material removal rate. Confocal laser scanning microscopy and scanning electron microscope are used to analyze the etching results, and scanning transmission electron microscope (STEM) is adopted to confirm the accuracy of this method. The STEM result also indicates that etching does not introduce any SSD, and the thoroughly etched surface is a perfectly single crystal. A rapid SSD screening ability is also demonstrated, showing that this method is a promising approach for the rapid detection of SSD

Molecular Control of Follicular Helper T cell Development and Differentiation

Follicular helper T cells (Tfh) are specialized helper T cells that are predominantly located in germinal centers and provide help to B cells. The development and differentiation of Tfh cells has been shown to be regulated by transcription factors, such as B-cell lymphoma 6 protein (Bcl-6), signal transducer and activator of transcription 3 (STAT3) and B lymphocyte-induced maturation protein-1 (Blimp-1). In addition, cytokines, including IL-21, have been found to be important for Tfh cell development. Moreover, several epigenetic modifications have also been reported to be involved in the determination of Tfh cell fate. The regulatory network is complicated, and the number of novel molecules demonstrated to control the fate of Tfh cells is increasing. Therefore, this review aims to summarize the current knowledge regarding the molecular regulation of Tfh cell development and differentiation at the protein level and at the epigenetic level to elucidate Tfh cell biology and provide potential targets for clinical interventions in the future

A reference-grade wild soybean genome

Wild relatives of crop plants are invaluable germplasm for genetic improvement. Here, Xie et al. report a reference-grade wild soybean genome and show that it can be used to identify structural variation and refine quantitative trait loci

A reference-grade wild soybean genome

Efficient crop improvement depends on the application of accurate genetic information contained in diverse germplasm resources. Here we report a reference-grade genome of wild soybean accession W05, with a final assembled genome size of 1013.2 Mb and a contig N50 of 3.3 Mb. The analytical power of the W05 genome is demonstrated by several examples. First, we identify an inversion at the locus determining seed coat color during domestication. Second, a translocation event between chromosomes 11 and 13 of some genotypes is shown to interfere with the assignment of QTLs. Third, we find a region containing copy number variations of the Kunitz trypsin inhibitor (KTI) genes. Such findings illustrate the power of this assembly in the analysis of large structural variations in soybean germplasm collections. The wild soybean genome assembly has wide applications in comparative genomic and evolutionary studies, as well as in crop breeding and improvement programs

Two Antarctic penguin genomes reveal insights into their evolutionary history and molecular changes related to the Antarctic environment. GigaScience

Abstract Background: Penguins are flightless aquatic birds widely distributed in the Southern Hemisphere. The distinctive morphological and physiological features of penguins allow them to live an aquatic life, and some of them have successfully adapted to the hostile environments in Antarctica. To study the phylogenetic and population history of penguins and the molecular basis of their adaptations to Antarctica, we sequenced the genomes of the two Antarctic dwelling penguin species, the Adélie penguin [Pygoscelis adeliae] and emperor penguin [Aptenodytes forsteri]. Results: Phylogenetic dating suggests that early penguins arose~60 million years ago, coinciding with a period of global warming. Analysis of effective population sizes reveals that the two penguin species experienced population expansions from~1 million years ago to~100 thousand years ago, but responded differently to the climatic cooling of the last glacial period. Comparative genomic analyses with other available avian genomes identified molecular changes in genes related to epidermal structure, phototransduction, lipid metabolism, and forelimb morphology. Conclusions: Our sequencing and initial analyses of the first two penguin genomes provide insights into the timing of penguin origin, fluctuations in effective population sizes of the two penguin species over the past 10 million years, and the potential associations between these biological patterns and global climate change. The molecular changes compared with other avian genomes reflect both shared and diverse adaptations of the two penguin species to the Antarctic environment

A study on pentacene organic thin-film transistors with Hf-based oxideas gate dielectric

Compared with its inorganic counterpart, organic thin-film transistor (OTFT) has advantages such as low-temperature fabrication, adaptability to large-area flexible substrate, and low cost. However, they usually need high operating voltage and thus are not suitable for portable applications. Although reducing their gate–dielectric thickness can lower the operating voltage, it increases their gate leakage. A better way is making use of high-κ gate dielectric, which is the main theme of this research. Firstly, pentacene OTFTs with HfO2 gate dielectric nitrided in N2O or NH3 at 200 oC were studied. The NH3-annealed OTFT displayed higher carrier mobility, larger on/off current ratio, smaller sub-threshold swing and smaller Hooge?s parameter than the N2O-annealed device. All these advantages were attributed to more nitrogen incorporation at the dielectric surface by the NH3 annealing which provided stronger passivation of surface traps. The incorporation of lanthanum to hafnium oxide was demonstrated to realize enhanced interface in the pentacene OTFTs. Therefore, pentacene OTFTs with HfLaO gate dielectric annealed in N2, NH3, O2 or NO at 400 oC were investigated. Among the 4 devices, the NH3-annealed OTFT obtained the highest carrier mobility, smallest sub-threshold swing and smallest 1/f noise. All these should be attributed to the improved interface between the gate dielectric and the organic semiconductor associated with the passivation effects of the NH3 annealing on the dielectric surface. The processing temperature of OTFTs is a big concern because use of flexible or glass substrate is the trend in organic electronics. Therefore, the HfLaO gate dielectric was annealed in N2, NH3, or O2 at two different temperatures, 200 oC and 400 oC. For all the annealing gases, the OTFTs annealed at 400 oC achieved higher carrier mobility, which could be supported by SEM image that pentacene tended to form larger grains (thus less carrier scattering) on HfLaO annealed at 400 oC. Furthermore, the HfLaO film annealed at 400 oC achieved much smaller leakage because more thermal energy at higher annealing temperature could remove oxide defects more effectively. Fluorination of the HfLaO film (annealed in N2 or NH3 at 400 oC) in a plasma based on CHF3 and O2 was also proposed. For both annealing gases, the OTFT with a 100-s plasma treatment achieved higher carrier mobility and smaller 1/f noise than that without plasma treatment. All these improvements should be due to fluorine incorporation at the dielectric surface which passivated the traps there. By contrast, for longer time (300 s or 900 s) of plasma treatment, the performance of the OTFTs deteriorated due to damage of dielectric surface induced by excessive plasma treatment. Lastly, a comparative study was done on pentacene OTFTs with HfLaO or La2O3 as gate dielectric. For the same annealing gas (H2, N2, NH3, or O2 at 400 oC), the OTFT with La2O3 gate dielectric obtained lower carrier mobility, smaller on/off current ratio, and larger threshold voltage than that based on HfLaO. The worse performance of the OTFTs with La2O3 gate dielectric was due to the degradation of La2O3 film caused by moisture absorption.published_or_final_versionElectrical and Electronic EngineeringDoctoralDoctor of Philosoph

Simulation Research on Ventilation Control of Gaseous Pollutants in Urban Sentry Boxes

The tiny spaces of sentry boxes in cities, such as mobile security guards, highway toll booths, etc., are mostly located beside roads with harsh outdoor environments. Due to office demands, work windows often need to be kept or frequently opened. The intrusion of outdoor pollutants through the windows leads to the deterioration of the indoor air quality, and threatens the health of employees. This paper takes the gaseous pollutant NO2 as the representative and discusses the effective ventilation design scheme for improving the air quality in the sentry box with openings using two attached ventilation modes as the carrier. Taking the vertical wall-attached ventilation as an example, the formation of the air curtain at the window hole and its barrier performance to outdoor pollutants were studied. The conclusion is that when the air supply velocity is sufficient to form a complete air curtain at the window hole, it can effectively block the pollutants. The horizontal wall-attached ventilation shows that clean air is delivered to the space with openings, and the indoor air quality can also be well improved due to the dilution effect, but the effect of positive pressure control is not obvious due to the large opening. The conclusions can provide guidance for the ventilation design of sentry boxes with openings