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摘要： This paper presents an in-depth study and analysis of the image feature extraction technique for ancient ceramic identification using an algorithm of partial differential equations. Image features of ancient ceramics are closely related to specific raw material selection and process technology, and complete acquisition of image features of ancient ceramics is a prerequisite for achieving image feature identification of ancient ceramics, since the quality of extracted area-grown ancient ceramic image feature extraction method is closely related to the background pixels and does not have generalizability. In this paper, we propose a deep learning-based extraction method, using Eased as a deep learning support platform, to extract and validate 5834 images of 272 types of ancient ceramics from kilns, celadon, and Yue kilns after manual labelling and training learning, and the results show that the average complete extraction rate is higher than 99%. The implementation of the deep learning method is summarized and compared with the traditional region growth extraction method, and the results show that the method is robust with the increase of the learning amount and has generalizability, which is a new method to effectively achieve the complete image feature extraction of ancient ceramics. The main content of the finite difference method is to use the ratio of the difference between the function values of two adjacent points and the distance between the two points to approximate the partial derivative of the function with respect to the variable. This idea was used to turn the problem of division into a problem of difference. Recognition of ancient ceramic image features was realized based on the extraction of the overall image features of ancient ceramics, the extraction and recognition of vessel type features, the quantitative recognition of multidimensional feature fusion ornamentation image features, and the implementation of deep learning based on inscription model

关键词： Acute lymphoblastic leukemia   Long non-coding RNA   mRNA   Next generation sequencing   Transcriptome network  

摘要： Background: Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides (nt) that are involved in the pathogenesis and development of various cancers including B cell acute lymphoblastic leukemia (B-ALL). To determine the potential roles of lncRNAs involved in pathogenesis of B-ALL, we analyzed the expression profile of lncRNAs and mRNAs in B-ALL, respectively, and constructed lncRNAs/mRNAs interaction network. Methods: We performed RNA sequencing of 10 non-leukemic blood disease donors and 10 B-ALL patients for Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Interactions among mRNAs were predicted using the STRING database. Quantitative real time PCR (qRT-PCR) was performed to verify the RNA-seq data of lncRNAs and mRNAs. Potential functions of subtype-specific lncRNAs were determined by using coexpression-based analysis on distally (trans-pattern) located protein-coding genes. Results: A total of 1813 differentially expressed transcripts (DETs) and 2203 lncRNAs were identified. Moreover, 10 dysregulated lncRNAs and 10 mRNAs were randomly selected, and further assessed by RT-qPCR in vitro. Go and KEGG analysis demonstrated that the differentially expressed mRNAs were most closely associated with myeloid leukocyte activation and in transcriptional misregulation in cancer, respectively. In addition, co-expression analysis demonstrated that these lncRNAs, including MSTRG.27994.3, MSTRG.21740.1, ENST00000456341, MSTRG.14224.1 and MSTRG.20153.1, may mediate the pathogenesis and development of B-ALL via lncRNA-mRNA network interactions. Conclusions: These results showed that several mRNAs and lncRNAs are aberrantly expressed in the bone marrow of B-ALL patients and play potential roles in B-ALL development, and be useful for diagnostic and/or prognostic purposes in pediatric B-ALL.

关键词： Optical signal processing  

摘要： Signal processing is a focused topic with communication technologies developing rapidly nowadays. However, optical signal processing methods are not so mature compared to the digital signal processors. Here, we propose an all-optical differentiator in frequency domain designed with fundamental optical elements, which is able to give the first order differentiation of the input signal. A fully theoretical description of the differentiator and its transfer function are demonstrated and discussed. According to experiments, the differentiator is proved reliable and the results match well with simulations. Moreover, an application of the frequency domain differentiator for measuring small time delay changes is also demonstrated and discussed. We believe that this work can give different perspectives of optical signal processing in frequency domain.

关键词： Dynamical system   optimal stopping   impulse control   dynamic programming   total cost  

摘要： When solving optimal impulse control problems, one can use the dynamic programming approach in two different ways: at each time moment, one can make the decision whether to apply a particular type of impulse, leading to the instantaneous change of the state, or apply no impulses at all;or, otherwise, one can plan an impulse after a certain interval, so that the length of that interval is to be optimised along with the type of that impulse. The first method leads to the differential Bellman equation, while the second method leads to the integral Bellman equation. The target of the current article is to prove the equivalence of those Bellman equations in many specific models. Those include abstract dynamical systems, controlled ordinary differential equations, piece-wise deterministic Markov processes and continuous-time Markov decision processes.

关键词： Differential game theory   dynamic game theory   optimal state-feedback strategies   state-feedback Nash equilibrium   pursuit-evasion games  

摘要： In this manuscript we formulate the general Target-Attacker-Defender differential game of degree in both its continuous-time and discrete-time turn-based variants in n-dimensional euclidean space. In this three-agent engagement, the Attackers goal is to get as close as possible to the Target before collision with the Defender, whilst the Target and Defender coordinate to achieve the opposite. The most general setting for this zero-sum differential game is considered, where the agents move at speeds not necessarily equal, and the Nash equilibrium strategies are proven in the discrete-time turn-based variant.

关键词： Differential steering   steering control   steering performance   multiobjective optimisation   in-wheel motors   steer-by-wire  

摘要： Differential steering is an emerging steering concept based on traction force differences between left and right sides of vehicles equipped with independently actuated wheels. Actually, this concept is only used to support classical vehicle designs utilising rack and pinion steering components. However, it may fully substitute such devices to reduce complexity and cut down costs. Since we do not have well-established design rules for such kind of vehicles, this paper will overcome the missing experience and explore the general applicability of such a new steering concept by using multiobjective optimisation. Three design objectives and three constraints are defined with respect to the dynamic, steady-state and low-speed steering performance of the vehicle. Since mechanical and control parts are strongly coupled, their parameters are optimised simultaneously by a multiobjective genetic algorithm aided by iteratively updated neural network-based response surface metamodels. Optimisation results in a variety of technically feasible Pareto-optimal designs. Investigation of a particular optimal design shows that a vehicle with differential steering is able to provide convincing steering performance.

关键词： Differential inclusions   homogeneous systems   stability  

摘要： The present paper is devoted to solution of the robust stabilisation problem for generalised homogeneous differential inclusions via dynamical feedback. The stability criterion is obtained. It is shown that asymptotically stable homogeneous differential inclusion is topologically equivalent to quadratically stable one via corresponding coordinate transformation. The results are supported with numerical examples of dynamical feedback design for an active suspension system.

关键词： Speech synthesis   pattern classifier   multilayer differential neuralnetworks   EEG signal analysis   EEG signal processing  

摘要： This manuscript proposes the design of a speech synthesis algorithm based on measured electroencephalographic (EEG) signals previously classified by a class of neural network with continuous dynamics. A novel multilayer differential neural network (MDNN) classifies a database with the EEG studies of 20 volunteers. The database contains information described by input-output pairs corresponding to EEG signals and a corresponding word imagined by the volunteer. The suggested MDNN estimates the unknown relationship between the information instances and suggests the most-likely word that the user wants mentioning. The proposed MDNN satisfactory classifies over 95% a set of words obtained from the suggested EEG study in which, the users have to watch four different geometric figures on a screen.

关键词： Singularity   C-1 positive solutions of impulsive differential equations   transformation technique   L-p-integrable   Sharp conditions  

摘要： Using a transformation technique to deal with the impulse term of a second-order singular impulsive differential equation, this paper establishes sharp conditions to guarantee the existence of C-1[0, 1] positive solutions. The results significantly extend and improve many known results for both the continuous case and more general nonsingular case.

关键词： Adsorption   clonal selection   ochratoxin A   phenolics   wine making   yeasts  

摘要： To design a rapid, simple, and low-cost procedure for yeast selection with differential adsorption activities toward phenolics and ochratoxin A, 284 yeast strains were screened. This was done by evaluating the type of growth during grape must fermentation, acetic acid production on Chalk agar, H2S production on BiGGY agar, and spore-formation on acetate agar. After that initial step, 84 strains were pre-selected and further studied by Petri plate tests and to determine their wine-making ability in trials and evaluating their differential adsorption activities toward phenolics and ochratoxin A. Three yeast strains were selected based on the above evaluations. After confirming that they belonged to Saccharomyces cerevisiae species and were diploids, a spore clonal selection was performed. The strain Sc1741A_1D was selected and used in winemaking at six Calabrian wineries and found to be suitable as wine starter to improve quality and safety of red wines.