新工科背景下现代设计方法教学探讨

“现代设计方法”是机电工程专业一门重要的专业必修课程。聚集于新工科中解决复杂工程问题的能力这一重要目标,针对目前教学中存在的一些不足之处,本文从教学内容、教学模式与教学方法等角度提出了相应的教学改革措施,为进一步培养学生解决复杂工程问题能力提供借鉴。     

A Low‐Complexity 128‐Point Mixed‐Radix FFT Processor for MB‐OFDM UWB Systems

In this paper, we present a fast Fourier transform (FFT) processor with four parallel data paths for multiband orthogonal frequency‐division multiplexing ultra‐wideband systems. The proposed 128‐point FFT processor employs both a modified radix‐2⁴ algorithm and a radix‐2³ algorithm to significantly reduce the numbers of complex constant multipliers and complex booth multipliers. It also employs substructure‐sharing multiplication units instead of constant multipliers to efficiently conduct multiplication operations with only addition and shift operations. The proposed FFT processor is implemented and tested using 0.18 µm CMOS technology with a supply voltage of 1.8 V. The hardware‐ efficient 128‐point FFT processor with four data streams can support a data processing rate of up to 1 Gsample/s while consuming 112 mW. The implementation results show that the proposed 128‐point mixed‐radix FFT architecture significantly reduces the hardware cost and power consumption in comparison to existing 128‐point FFT architectures.     

复杂约束条件下伴随修理任务多目标动态调度

针对战时伴随修理任务重、修理时间有限、约束复杂的问题,提出了伴随修理装备维修任务调度的多目标动态调度方法。考虑复杂约束的伴随修理装备维修任务调度军事需求,构建了多目标动态调度模型。该模型在修理能力及修理时间限制的基础上,引入修理时间窗、非遍历约束,考虑修理能力变化以及修复状态的不确定性,以修竣装备总数、修竣装备重要度总和、获得的二次作 战总时间最大为调度目标,进行维修任务的调度决策。设计了基于改进非支配排序遗传算法（NSGA-II）的改进多目标遗传算法进行模型求解,并通过示例仿真与分析验证了该模型和算法的合理性及有效性。     

双波长共振全息CT测量燃烧场的理论研究

双波长共振全息干涉图信息提取靠条纹的移动和强度衰减的测量,而信息的准确获得需要建立极好的复折射率模型。本文介绍了经典理论模型,推导了量子理论的复折射率表达式,并由此通过测量条纹的移动和强度衰减程度,获得燃烧场的温度和组分浓度的信息。     

Functional Materials for Memristor-Based Reservoir Computing: Dynamics and Applications

The booming development of artificial intelligence (AI) requires faster physical processing units as well as more efficient algorithms. Recently, reservoir computing (RC) has emerged as an alternative brain-inspired framework for fast learning with low training cost, since only the weights associated with the output layers should be trained. Physical RC becomes one of the leading paradigms for computation using high-dimensional, nonlinear, dynamic substrates. Among them, memristor appears to be a simple, adaptable, and efficient framework for constructing physical RC since they exhibit nonlinear features and memory behavior, while memristor-implemented artificial neural networks display increasing popularity towards neuromorphic computing. In this review, the memristor-implemented RC systems from the following aspects: architectures, materials, and applications are summarized. It starts with an introduction to the RC structures that can be simulated with memristor blocks. Specific interest then focuses on the dynamic memory behaviors of memristors based on various material systems, optimizing the understanding of the relationship between the relaxation behaviors and materials, which provides guidance and references for building RC systems coped with on-demand application scenarios. Furthermore, recent advances in the application of memristor-based physical RC systems are surveyed. In the end, the further prospects of memristor-implemented RC system in a material view are envisaged.     

反舰导弹武器系统如何提高复杂电磁环境下的抗干扰能力

分析了反舰导弹武器系统面临的复杂电磁环境,提出了复杂电磁环境下反舰导弹武器系统面临的挑战,在此基础上给出了反舰导弹武器系统提高复杂电磁环境下抗干扰能力应采取的措施。     

分析大口径凹形结构散射的一种混合射线方法

在大口径凹形结构散射的特点及有关分析方法的基础上,提出了一类基于复射线方法和几何绕射方法的分析处理大口径凹形结构散射的混合射线方法,即用复射线法计算反射场,以几体绕射法来计算边缘绕射场。基于所设计的便于工程上实现的计算流程,有关分析及相关结果说明了这一方法的可行性和可靠性。     

High triplet energy Al complex as a host material for blue phosphorescent organic light-emitting diodes

An Al complex, tris((2-(pyrazol-1-yl)pyridin-3-yl)oxy)aluminum (Al(pypy)₃), was synthesized as a high triplet energy host material for blue phosphorescent organic light-emitting diodes. A high triplet energy ligand, 2-(1H-pyrazol-1-yl)pyridin-3-ol, was coordinated to the Al to develop the high triplet energy host material derived from Al. The Al(pypy)₃ host showed a high triplet energy of 2.86 eV for efficient energy transfer to blue triplet emitter. A maximum quantum efficiency of 20.5% was achieved in blue device using the Al(pypy)₃ host material.     

Synthesis and optoelectronic properties of novel fluorene-bridged dinuclear cyclometalated iridium (III) complex with A–D–A framework in the single-emissive-layer WOLEDs

To explore the influence of push–pull chromophores on properties of emitter in organic light-emitting devices (OLEDs), an acceptor–donor–acceptor (A–D–A)-based dinuclear iridium (III) complex of (dfppy)₄Ir₂(dipic-FL) was synthesized via Suzuki coupling reaction, in which dfppy is 2-(2,4-difluorophenyl)pyridine and dipic-FL is 2,7-di(5-pyridyl-2-carboxyl)-9,9-dioctyl-9H-fluorene. An intense emission peak at about 480 nm resulting from the (dfppy)₂Ir(pic) chromophore and a weak long-wavelength emission band at 580–660 nm attributed to intramolecular charge transfer transition were exhibited for (dfppy)₄Ir₂(dipic-FL) in dichloromethane solution. But a remarkably hypsochromic photoluminescence profile with an intense characteristical emission peak at 422 nm was observed, which is attributed to the intraligand (IL) π–π^∗ excited states in its thin film. White emission with a maximum luminance of 1040 cd/m² and current efficiency of 1.2 cd/A was obtained in its single-emissive-layer (SEL) OLEDs with a configuration of ITO/PEDOT:PSS/(dfppy)₄Ir₂(dipic-FL) (10 wt%):TCTA/TPBi/LiF/Al. To our knowledge, this is one of the best examples in term of dinuclear iridium complex as single dopant in the high-performance white-emitting SEL-OLEDs.     

二维TE波中的HIE-CPML算法

文中将坐标伸缩完全匹配层CPML引入到弱无条件稳定算法HIE-FDTD中研究其吸波性能。详细推导了2维TE波模型中CPML在HIE-FDTD算法中应用的差分公式。为检验本文所提方法的吸波效能,建立了计算模型,将其与其它吸收边界条件的吸波性能进行了综合比较,计算了HIE-FDTD算法选取不同条件数时的反射误差,并详细说明如何合理选取α,κmax和σmax来实现最佳相对误差。结果显示：当将本文所提方法的CPML层数设置为8时,其反射误差为-62 dB,低于传统FDTD方法的-58 dB;当选取α=0.05,κmax=10,σmax/σopt=1.3可以实现低至-83 dB的最大相对误差;在仿真中,其比传统FDTD方法也约减少48%的计算时间。