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51.
为了实现对假手的智能控制,文中提出一种基于语音控制的设计方案。语音识别系统接收发音人的语音命令,并将语音命令转换成主控系统能识别的数字信号。主控系统接收数字信号,同时根据命令向指关节发送数据驱动指关节伺服电机正向或反向转动。指关节转动的角度被指关节电位器转换成相应的电信号。主控系统将角度电信号转换成数字信号,并将此数字信号和命令初始数据比较,从而发出修正命令数据,驱动指关节伺服电机走到指定的位置。在抓握不同物品时,本系统中在每个指尖安装有高灵敏度的压力传感器以检测指尖的受力,确保物品既被抓牢又不被压坏,从而实现对假手的智能控制。 相似文献
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本文在介绍我院电气工程及其自动化专业自2006年开展"2+6"实践教学改革的基础上,围绕"卓越计划"校企联合培养应重点关注的问题,从实习企业、教学内容、时间安排、教学方法、管理考核和教学成效等方面。本文举例说明了我院进行"卓越计划"校企联合培养的做法。 相似文献
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为了改善1Cr5Mo耐热钢焊接接头拉伸力学性能,利用CO2激光对其进行了表面改性处理,通过拉伸试验考察了激光热处理对拉伸性能的影响.利用扫描电镜观察了焊接接头的断裂形式和断口形貌,并用能谱仪分析了激光热处理前后试样表面化学元素的组成,讨论了残余应力和残余奥氏体对拉伸性能的影响.结果表明,激光热处理前后试样的拉伸断口均为韧性断裂,激光热处理后断裂性能有所提高;激光热处理试样表面产生晶粒细化和残余压应力的强化层,其屈服强度和抗拉强度分别提高了3.4%和13.7%,拉伸性能得到进一步提高;激光热处理试样的残余奥氏体含量有所降低,导致焊接接头的断面收缩率下降了18.61%,而延伸率基本不变,其均匀变形能力有所增强. 相似文献
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为了研究水印辅助的低密度奇偶校验(LDPC)方 案在高速相干接收光通信系统 中的译码性能,提出了一种适用于相干光通信系统的水印符号辅助的LDPC前向纠错方案 ,与传统LDPC相比,可以大大提高相干接 收机的抗噪声能力。在100Gbit/s 16进制正 交幅度高制(16QAM)相干接收光通信系统上的仿真实验结果表明, 在误码率(BER)为10-9时, 所提出的前向纠错方案与传统LDPC相比 较,信噪比(SNR)增益提高了0.45dB ;同时,在相同BER下,水印符号辅助的LDPC方 案的译码迭代次数有很明显的降低。 相似文献
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Siriwan Ongchai Natthakarn Chiranthanut Siriwan Tangyuenyong Nawarat Viriyakhasem Patiwat Kongdang 《Molecules (Basel, Switzerland)》2021,26(6)
Kaempferia parviflora Wall. ex Baker (KP) has been reported to attenuate cartilage destruction in rat model of osteoarthritis. Previously, we demonstrated that KP rhizome extract and its active components effectively suppressed mechanisms associated with RA in SW982 cells. Here, we further evaluated the anti-arthritis potential of KP extract by using multi-level models, including a complete Freund’s adjuvant-induced arthritis and a cartilage explant culture model, and to investigate the effects of KP extract and its major components on related gene expressions and underlying mechanisms within cells. In arthritis rats, the KP extract reduced arthritis indexes, with no significant changes in biological parameters. In the cartilage explant model, the KP extract exerted chondroprotective potential by suppressing sulfated glycosaminoglycans release while preserving high accumulation of proteoglycans. In human chondrocyte cell line, a mixture of the major components equal to their amounts in KP extract showed strong suppression the expression of genes-associated inflammatory joint disease similar to that of the extract. Additionally, KP extract significantly suppressed NF-κB and MAPK signaling pathways. The suppressing expression of necroptosis genes and promoted anti-apoptosis were also found. Collectively, these results provided supportive evidence of the anti-arthritis properties of KP extract, which are associated with its three major components. 相似文献
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Luminita Marin Marcel Popa Alexandru Anisiei Stefan-Andrei Irimiciuc Maricel Agop Tudor-Cristian Petrescu Decebal Vasincu Loredana Himiniuc 《Molecules (Basel, Switzerland)》2021,26(7)
The aim of the study was to create a mathematical model useful for monitoring the release of bioactive aldehydes covalently bonded to the chitosan by reversible imine linkage, considered as a polymer–drug system. For this purpose, two hydrogels were prepared by the acid condensation reaction of chitosan with the antifungal 2-formyl-phenyl-boronic acid and their particularities; influencing the release of the antifungal aldehyde by shifting the imination equilibrium to the reagents was considered, i.e., the supramolecular nature of the hydrogels was highlighted by polarized light microscopy, while scanning electron microscopy showed their microporous morphology. Furthermore, the in vitro fungicidal activity was investigated on two fungal strains and the in vitro release curves of the antifungal aldehyde triggered by the pH stimulus were drawn. The theoretical model was developed starting from the hypothesis that the imine-chitosan system, both structurally and functionally, can be assimilated, from a mathematical point of view, with a multifractal object, and its dynamics were analyzed in the framework of the Scale Relativity Theory. Thus, through Riccati-type gauges, two synchronous dynamics, one in the scale space, associated with the fungicidal activity, and the other in the usual space, associated with the antifungal aldehyde release, become operational. Their synchronicity, reducible to the isomorphism of two SL(2R)-type groups, implies, by means of its joint invariant functions, bioactive aldehyde compound release dynamics in the form of “kink–antikink pairs” dynamics of a multifractal type. Finally, the theoretical model was validated through the experimental data. 相似文献