摘要：Free electron lasers provide high-power and ultrashort pulses with extreme brightness. In order to improve a facility's capabilities and explore the possibility of performing high-resolution time-resolved experiments, a beam arrival time resolution under 100 fs is required. In this article, a novel beam arrival time monitor(BAM)equipped with two cavities has been designed and a beam flight time measurement scheme based on the BAM prototype has been proposed to estimate phase jitter in the signal measurement system. The two BAM cavities work at different frequencies and the frequency difference is designed to be 35 MHz. Therefore, a self-mixing intermediate frequency signal can be generated using the two cavities. The measured beam flight time shows a temporal deviation of 37 fs(rms).

摘要：Antimicrobial peptides may be regarded as a potential source of future antibiotics, and the modes of action have implicated the cationic and hydrophobic nature of their interaction with bacterial membranes. In the present study, a 16-residue peptide (LGR16) was developed with the aim of examining the feasibility of designing an antimicrobial peptide by segregating hydrophobic residues in the nonpolar side and positively charged residues in the polar side, based on the helical wheel projections. Antimicrobial activity, hemolytic activity, cytotoxicity against mammalian cells and bactericidal kinetics were investigated to fully evaluate the biological function of the peptide. The results showed that the peptide LGR16 had strong antimicrobial activity, and its MICs against Gram-negative and Gram-positive bacteria were 8 and 4 μg/mL, respectively. LGR16 also exhibited rapid bactericidal action and had totally eradicated the bacteria at 10 min. LGR16 showed only weak hemolysis against chicken red blood cells and cytotoxicity aginst Vero cells at its MICs, and the concentration that caused 50% hemolysis exceeded its MICs 8-fold. Overall, antimicrobial peptides can be designed by assembling hydrophobic residues in the hydrophobic side and basic residues in the opposite side. The peptide LGR16 may be developed as a prospective candidate for an antimicrobial drug.

摘要：针对当前边缘提取算法的实时性问题,提高图像边缘连续性,提出基于量子柔性表示(flexible representation of quantum,FRQ)的边缘提取算法。将图像进行量子柔性表示,利用量子序列的叠加态存储图像的所有像素,通过量子并行计算显著提高效率,得到FRQ图像;对FRQ图像进行X、Y方向的平移变换,获得整个图像的邻域像素的相对量子;根据量子比特定义量子黑盒UΩ,结合Sobel算子计算像素的Sobel梯度,判断不同类别的像素并提取图像的边缘。实验结果表明,与当前边缘提取算法相比,所提方法具有更好的边缘连续性与更丰富的细节边缘。

摘要：This paper proposes a kind of programmable logic element(PLE)based on Sense-Switch pFLASH *** programming Sense-Switch pFLASH,all three-bit look-up table(LUT3)functions,partial four-bit look-up table(LUT4)functions,latch functions,and d flip flop(DFF)with enable and reset functions can be *** PLE uses a choice of operational logic(COOL)approach for the operation of logic functions,it allows any logic circuit to be implemented at any ratio of combinatorial logic to *** intrinsic property makes it close to the basic application specific integrated circuit(ASIC)cell in terms of fine granularity,thus allowing ASIC-like cell-based mappers to apply all their optimization *** measuring Sense-Switch pFLASH and PLE circuits,the results show that the“on”state driving current of the Sense-Switch pFLASH is about 245.52μA,and that the“off”state leakage current is about 0.1 *** programmable function of PLE works *** delay of the typical combinatorial logic operation AND3 is 0.69 ns,and the delay of the sequential logic operation DFF is 0.65 ns,both of which meet the requirements of the design technical index.

摘要：The presentation and modeling of turbulence anisotropy are crucial for studying large-scale turbulence structures and constructing turbulence ***,accurately capturing anisotropic Reynolds stresses often relies on expensive direct numerical simulations(DNS).Recently,a hot topic in data-driven turbulence modeling is how to acquire accurate Reynolds stresses by the Reynolds-averaged Navier-Stokes(RANS)simulation and a limited amount of data from *** existing studies use mean flow characteristics as the input features of machine learning models to predict high-fidelity Reynolds stresses,but these approaches still lack robust generalization *** this paper,a deep neural network(DNN)is employed to build a model,mapping from tensor invariants of RANS mean flow features to the anisotropy invariants of high-fidelity Reynolds *** the aspects of tensor analysis and input-output feature design,we try to enhance the generalization of the model while preserving invariance.A functional framework of Reynolds stress anisotropy invariants is derived *** irreducible invariants are then constructed from a tensor group,serving as alternative input features for ***,we propose a feature selection method based on the Fourier transform of periodic *** results demonstrate that the data-driven model achieves a high level of accuracy in predicting turbulence anisotropy of flows over periodic hills and converging-diverging ***,the well-trained model exhibits strong generalization capabilities concerning various shapes and higher Reynolds *** approach can also provide valuable insights for feature selection and data generation for data-driven turbulence models.

摘要：基于ANSYS Workbench建立了重型装备与储运装置的三维模型、离散化模型、接触模型。以储存与起吊为典型工况,计算了超静定储运装置的刚度和强度状态;基于Mises屈服理论,对储运装置的强度进行评估;通过调整承载部位刚度,优化了储运装置各承载部位力的分配,提高了储运装置钢架节点受力合理性。研究结果表明,有限元方法能够为超静定结构的储运装置提供设计和优化依据。

摘要：分析了北京顺义文化创意产业空间发展历程和特征,比较了顺义文创产业聚集情况与北京中心城区的关系。发现其空间布局较为凌乱,没有充分利用顺义现有的各类资源禀赋,与其空间区位优势不匹配、且东西空间发展差异巨大。文章归纳了文化创意产业对空间的需求特征,并根据文创产业发展趋势,针对性地提出了空间优化策略。

摘要：Due to the wide railway network and different characteristics of many earthquake zones in China,considering the running safety performance of trains(RSPT)in the design of high-speed railway bridge structures is very *** this study,in order to provide the seismic design and evaluation measure of the bridge structure based on the RSPT,a calculation model of RSPT on bridge under earthquake was established,and the track surface response measure when the derailment coefficient reaches the limit value was calculated by referring to 15 commonly used ground motion(GM)intensity *** on the coefficient of variation of the limit value obtained from multiple GM samples,the optimal measures were ***,the limit value of bridge seismic response based on RSPT with different train speeds and structural periods was determined.

摘要：目的:针对空降兵军事体能训练中存在的训练方式单一、训练计划缺乏针对性、训练伤发生率偏高等问题,设计一种基于人体成分分析的智能化空降兵军事体能训练系统。方法:该系统基于浏览器/服务器(Browser/Server,B/S)架构设计,采用Python语言开发,主要包括空降兵信息采集、训练者体能状态评估、体能训练计划推荐、空降兵军事体能训练计划评价4个功能模块。其中空降兵信息采集模块基于人体成分分析仪采集并分析训练者的生理参数信息,并根据军事体能训练需求明确与体能训练相关的参数特征,构建训练者体能评估参数模型;训练者体能状态评估模块基于机器学习方法构建训练者体能状态评估模型,实现空降兵阶段性体能评价功能;体能训练计划推荐模块基于体能训练特征相似性算法及图嵌入理论构建,为空降兵体能训练提供计划制订辅助决策;空降兵军事体能训练计划评价模块通过列表、图表等方式对比训练前后体能、评价结果,并基于评估结果调用空降兵军事体能训练计划推荐模块更新训练计划。结果:采用该系统辅助空降兵军事体能训练,可在受训者肌体评估的基础上建立个性化体能训练推荐机制,并通过阶段性训练评价的对比、反馈及时调整计划,从而降低训练伤发生率,并提高训练效果。结论:该系统提高了空降兵军事体能训练的科学性及可靠性,为我军的智能化军事训练提供了参考。

摘要：目的超现实主义的艺术具有虚幻性和无穷的想象力,其理念一直引领着创新。旨在基于超现实主义雕塑的艺术理念,对家具创新设计进行研究,挖掘超现实主义优质特色,打破家具设计边界,实现艺术与技术统一,达到功能、情感与文化的融合。方法通过定性研究对超现实主义雕塑内涵与形式进行整理,了解其现状;从外观与内涵层面汲取设计灵感,提炼最具代表性的设计元素;运用跨学科研究法重点分析超现实主义雕塑的技术手法;最后从审美功能、实用功能、情感功能三方面出发,结合技术手法,将超现实主义雕塑元素与椅子外观和功能相融合,完成设计实践。结论基于超现实主义雕塑的椅子设计不仅有利于打破家具设计呆板的局面,为我国家具情感化设计的研究提供新思路,而且也为中国家具设计挖掘传统、走向国际市场提供了方法借鉴。