Ultrahigh‐Working‐Frequency Embedded Supercapacitors with 1T Phase MoSe2 Nanosheets for System‐in‐Package Application

Commercial aluminium electrolyte capacitors (AECs) are too large for integration in future highly integrated electronic systems. Supercapacitors, in comparison, possess a much higher capacitance per unit volume and can be embedded as passive capacitors to address such challenges in electronics scaling. However, the slow frequency response (<10¹ Hz) typical of supercapacitors is a major hurdle to their practical application. Here, it is demonstrated that 1T‐phase MoSe₂ nanosheets obtained by laser‐induced phase transformation can be used as an electrode material in embedded micro‐supercapacitors. The metallic nature of MoSe₂ nanosheet‐based electrodes provides excellent electron‐ and ion‐transport properties, which leads to an unprecedented high‐frequency response (up to 10⁴ Hz) and cycle stability (up to 10⁶ cycles) when integrated in supercapacitors, and their power density can be ten times higher than that of commercial AECs. Furthermore, fabrication processes of the present device are fully compatible with system‐in‐package device manufacturing to meet stringent specifications for the size of embedded components. The present research represents a critical step forward in in‐package and on‐chip applications of electrolytic capacitors.     

TMS320C6701 DSP自动加载研究

在嵌入式系统中,经常要求上电后系统能自动把程序从DSP外部的ROM加载到片内RAM执行.给出一种基于TMS320C6701 DSP的ROM加载方案,通过配置CCS中DSP/BIOS模块的参数实现DSP程序中代码和数据段的先后分开加载,比传统的由手动编写连接命令文件(.CMD)实现自动加载更为方便.在此基础上,设计并实现了用CCS直接对FLASH芯片进行在线烧写.实验证明,该DSP加载方案稳定可靠,且易于实现.     

怀山药黄酒抗氧化活性的研究

以还原能力、DPPH自由基清除能力、羟基自由基清除能力和超氧阴离子自由基清除能力等4种抗氧化能力为指标,对怀山药黄酒和去皮怀山药黄酒在不同发酵时期的抗氧化活性进行研究,并与市售黄酒样品、自制黄酒和怀山药14%vol酒精浸泡液进行比较分析。结果表明,怀山药黄酒的抗氧化活性远高于其他样品,各指标分别为市售黄酒样品的1.71~9.09倍、自制黄酒的1.47~5.01倍、怀山药14%vol酒精浸泡液的1.96~5.41倍,且怀山药黄酒的抗氧化活性高于去皮怀山药黄酒。怀山药黄酒不同极性组分的萃取相中,还原能力的大小依次为正丁醇相>水相>乙酸乙酯相>二氯甲烷相>石油醚相,DPPH自由基清除能力依次为水相>石油醚相>正丁醇相>乙酸乙酯相>二氯甲烷相。     

The improved magnetic properties of FeSi powders cores composed with different size particles

Journal of Materials Science: Materials in Electronics - FeSi powder cores are prepared by cold pressing the mixture of 200 mesh and 400 mesh FeSi powders, the influence of 400 mesh powder (fine...     

微燃烧温差发电系统的研究进展

微燃烧温差发电系统由于结构简单,布置灵活,无运动部件等优点,更易应用于微小型设备中。文章对微燃烧温差发电系统的研究进行了概述,分析了目前存在的主要问题,为微燃烧温差发电系统的进一步研究提供了依据。     

Real option approach to evaluate cores for remanufacturing in service markets

Acquisition of cores is important for the success of remanufacturing business, but evaluating the value of cores is difficult due to many uncertain issues in the remanufacturing system. In this paper, we examine the value of cores using the real option valuation (ROV) approach, which well captures the production flexibility and represents different operations options in remanufacturing. First, in a system where the demand of remanufactured products is low, we focus on the uncertainty of price. We compare the cases where disposing cores occurs only at the expiration time and before that. The model also identifies under which circumstances disposing core early brings in more benefit. Furthermore, we study a remanufacturing system where demand and return are both uncertain. In this case, a spread option is used for evaluating the marginal value of obtaining additional cores. This approach also brings the advantage of linking the correlation between demand and return, which in fact is often exhibited in remanufacturing. The numerical experiments indicate that this correlation has an impact on collecting policies. This study illustrates the possibility of using ROV for core pricing modelling, and the study results also provide some managerial insights in managing returned cores.     

机器学习在听性脑干诱发电位数据分析中的应用研究

近年来,许多学者将机器学习算法应用到肌电信号(EMG)数据分析中,取得了良好的效果,但是主要针对手势识别等应用研究,较少有学者对辅助临床诊断进行研究。针对模型训练所需数据较大和机器学习在听性脑干诱发电位(ABR)数据分析中的应用较少两种问题。研究了机器学习方法在基于小型ABR数据集数据的计算机辅助诊断中的应用。收集了四川省中医医院的2 352份肌电图检查报告,通过设计纳入标准并进行数据清洗,构建了包含233份ABR报告的数据集。之后,使用数据标准化方法对数据进行数据预处理,再使用随机森林、线性回归、Logistic回归和人工神经网络4种机器学习算法对数据集进行分析处理。4种算法的性能对比表明随机森林算法性能最优,其准确率、召回率、精确率分别达到了0.995 7、0.989 7、0.950 0。此外还对每种算法在数据标准化前后的性能进行了比较,表明标准化处理对准确率的提高有一定的提升效果。随机森林算法输出的特征重要性表明,ABR检查中最重要的指标是L_latency_5、L_latency_A和L_Interval_35,其次是L_latency_b和L_latency_4。这些指标重要性融入上位机软件有助于提高临床诊断效率,在临床应用中具有较高的临床判读潜力。     

Microstructure and Electrical Properties of (K, Na, Li)NbO3–Pb(Zr,Ti)O3 Piezoelectric Ceramics

A new type (1− x )(K_0.485Na_0.485Li_0.03)NbO₃– x Pb(Zr_0.53Ti_0.47)O₃ piezoelectric ceramics was fabricated by conventional ceramics sintering technique. Their microstructure and electrical properties of the ceramics were also studied. X-ray diffraction and scanning electron microscopy patterns indicate that all ceramics samples exhibit a pure perovskite and highly dense structure, and the coexistence of the tetragonal and orthorhombic phases is formed; The ceramic with x =0.75 exhibits the following excellent properties: d ₃₃=363 pC/N, k _p=63%, Q _m=142, ɛ_r=1590, tan δ=1.70%, P _r=28.6 μC/cm², E _c=0.89 kV/mm, T _c=295°C. These results indicate that the ceramic is a promising candidate for piezoelectric ceramics in practical applications.