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1.
《全球能源互联网(英文)》2022,5(6):618-626
A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper. In this method, the original image sequence data is first separated from the foreground and background. Then, the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction. Finally, human posture nodes are extracted from each frame of the image sequence, which are then used to identify the abnormal behavior of the human. Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification. 相似文献
2.
Qian-Yun Han Fang Liu Yuan-Ying Ni 《International Journal of Food Science & Technology》2022,57(2):920-930
The gene sequence coding for the membrane-bound polyphenol oxidase (mPPO) with a length of 1761 bp was cloned by PCR method and shown to contain one highly conserved sequence encoding a di-copper-binding region. The predicted three-dimensional structure of mPPO indicated that the active site was located near two copper ions and composed of a typical bundle of four α-helices. Each of the two catalytic copper ions was coordinated with three histidine residues in the hydrophobic pocket, yielding His 180, His 201, His 210, His 332, His 336 and His 366. Docking studies showed that 4-methylcatechol and chlorogenic acid have different binding models due to different ligand sizes and binding sites in the active centre, and it was found that the smaller compound exhibited a higher affinity for mPPO. Molecular dynamic simulation results indicated that Phe 353 is important in controlling enzymatic activity through influencing substrate coordination in the active site. 相似文献
3.
ABSTRACTThis paper studies stochastic optimization problems with polynomials. We propose an optimization model with sample averages and perturbations. The Lasserre-type Moment-SOS relaxations are used to solve the sample average optimization. Properties of the optimization and its relaxations are studied. Numerical experiments are presented. 相似文献
4.
Araliya Mosleh Kheirollah Sepahvand Humberto Varum José Jara Mehran S. Razzaghi Steffen Marburg 《Structure and Infrastructure Engineering》2018,14(10):1324-1338
This paper focuses on the stochastic response of concrete bridges considering uncertainty in bearing and abutment stiffness. A multi-span simply supported bridge with concrete girders is selected. A 3D-dimensional model is prepared, and nonlinear response history analyses are performed. For the numerical dynamic simulation, the non-sampling stochastic method based on generalized polynomial chaos (gPC) expansion is utilised. The uncertain parameters include the vertical and shear stiffness of bearings and the lateral stiffness of abutments are presented by the truncated gPC expansions. Furthermore, the system response such as base shear, acceleration, velocity and displacement in different columns is presented by gPC expansion with unknown deterministic coefficients. The stochastic Galerkin projection is employed to calculate a set of deterministic equations. A non-intrusive solution, as a set of collocation points, determines the unknown gPC coefficients of the system response and the results are compared with Monte Carlo simulations. The key advantage of spectral discretization is the combination of the mentioned method with the spatial discretization, e.g. finite element model. This study also emphasises the accuracy in results and time efficiency of the proposed non-sampling method for uncertainty quantification of stochastic systems comparing to sampling procedure (e.g. Monte Carlo simulation). 相似文献
5.
Dr. Hu Zeng Bo He Prof. Chengqi Yi 《Chembiochem : a European journal of chemical biology》2019,20(15):1898-1905
Over the past few decades, various DNA modification detection methods have been developed; many of the high-resolution methods are based on bisulfite treatment, which leads to DNA degradation, to a degree. Thus, novel bisulfite-free approaches have been developed in recent years and shown to be useful for epigenome analysis in otherwise difficult-to-handle, but important, DNA samples, such as hmC-seal and hmC-CATCH. Herein, an overview of advances in the development of epigenome sequencing methods for these important DNA modifications is provided. 相似文献
6.
The effect of ZnO/K2O (Z/K) ratio on the crystallization sequence and microstructure of lithium disilicate (Li2Si2O5: LS2) glass-ceramics was carefully investigated for the SiO2-Li2O-K2O-ZnO-P2O5 system. The Z/K ratios of precursor glasses were varied from 0 to 3.5 while the nucleating agent of P2O5 and glass modifiers of ZnO plus K2O were fixed to have 1.5 and 4.5 mol% relative to LS2, respectively. For the samples prepared by two-stage heat treatments of 500 °C for 1 h and 800 °C for 2 h in air, the LS2 nucleation rate was increased with increasing the Z/K ratio due to the variation in crystallization sequence from type II (Li2SiO3: LS) to type I (LS + LS2) in addition to an amorphous phase separation in base glass. Consequently, with increasing the Z/K ratio, the LS2 crystalline phase within the glass matrix continuously changed from larger acicular ones to smaller equiaxed ones. 相似文献
7.
8.
针对自然语言处理(NLP)生成式自动摘要领域的语义理解不充分、摘要语句不通顺和摘要准确度不够高的问题,提出了一种新的生成式自动摘要解决方案,包括一种改进的词向量生成技术和一个生成式自动摘要模型。改进的词向量生成技术以Skip-Gram方法生成的词向量为基础,结合摘要的特点,引入词性、词频和逆文本频率三个词特征,有效地提高了词语的理解;而提出的Bi-MulRnn+生成式自动摘要模型以序列映射(seq2seq)与自编码器结构为基础,引入注意力机制、门控循环单元(GRU)结构、双向循环神经网络(BiRnn)、多层循环神经网络(MultiRnn)和集束搜索,提高了生成式摘要准确性与语句流畅度。基于大规模中文短文本摘要(LCSTS)数据集的实验结果表明,该方案能够有效地解决短文本生成式摘要问题,并在Rouge标准评价体系中表现良好,提高了摘要准确性与语句流畅度。 相似文献
9.
针对时域不确定信息的融合难题,为充分体现时域信息融合的动态性特点和时间因素对融合的影响,在证据理论的基础上,提出一种考虑决策者时序偏好的时域证据融合方法。首先将决策者对时序的偏好融入时域证据融合,通过分析时域证据序列的特点,在定义时序记忆因子的基础上,对决策者的时序偏好进行度量;然后通过构建优化模型求解时序权重,再结合证据信任度的概念,对证据源进行修正;最后利用Dempster组合规则对修正后的证据进行融合。数值算例表明,与没有考虑时间因素的融合方法相比,考虑决策者时序偏好的证据融合方法可以有效处理时域信息序列中的冲突信息,得到合理的融合结果;同时,所提方法充分考虑了时域证据序列的信任度和决策者的主观偏好,可以反映决策者主观因素对时域证据融合的影响,较好地体现了时域证据融合的动态性特点。 相似文献
10.
Mircea V. Diudea 《Fullerenes, Nanotubes and Carbon Nanostructures》2019,27(4):367-374
Rhombellanes are mathematical structures, proposed by us in 2017; they may appear both in periodic crystals or in finite structures. The simplest rhombellane is rbl.5 or K2.3, the complete bipartite graph. In this paper, rhombellation operation is iteratively applied on three classes of structures: cube, tori and cubic pcu-network, respectively. The structural topological parameters are detailed. 相似文献