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Effects of grain size on the corrosion resistance of pure magnesium by cooling rate-controlled solidification

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Frontiers of Materials Science 2015年第3期9卷 247-253页

作者： yichi liu Debao liu then YOU Minfang CHEN School of Materials Science and Engineering Tianjin University of Technology Tianjin 300384 China

The aim of this study was to investigate the effect of grain size on the corrosion resistance of pure magnesium developed for biomedical applications. High- purity magnesium samples with different grain size were prepared by the cooling rate- controlled solidification, Electrochemical and immersion tests were employed to measure the corrosion resistance of pure magnesium with different grain size. The electrochemical polarization curves indicated that the corrosion susceptibility increased as the grain size decrease. However, the electrochemical impedance spectroscopy （EIS） and immersion tests indicated that the corrosion resistance of pure magnesium is improved as the grain size decreases. The improvement in the corrosion resistance is attributed to refine grain can produce more uniform and density film on the surface of sample.

关键词： pure magnesium solidification cooling rate grain size corrosion resistance

Effects of solidification cooling rate on the corrosion resistance of Mg–Zn–Ca alloy

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Progress in Natural Science:Materials International 2014年第5期24卷 452-457页

作者： Debao liu yichi liu Yan Huang Rong Song Minfang Chen School of Materials Science and Engineering Tianjin University of Technology BCAST Brunel University

This study was carried out to investigate the effect of solidification cooling rate on the corrosion resistance of an Mg–Zn–Ca alloy developed for biomedical applications. A wedge shaped copper mould was used to obtain different solidification cooling rates. Electrochemical and immersion tests were employed to measure the corrosion resistance of Mg–Zn–Ca alloy. It was found that increasing cooling rate resulted in a significant improvement in the corrosion resistance of the Mg–Zn–Ca alloy. The findings were explained in terms of solidification behaviour in association with the change in solubility of the alloying elements, microstructural homogeneity and refinement and chemical homogeneity as well as the increased cooling rates.

关键词： Mg–Zn–Ca alloy Solidification cooling rate Microstructure Corrosion resistance

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基于ACNN的配电网故障识别与定位研究

微型电脑应用 2024年第2期40卷 149-153页

作者：吴方权代湘蓉刘亦驰贵州电网有限责任公司信息中心贵州贵阳550003

针对目前配电网故障诊断时存在计算时间长、定位精度低的问题,提出了一种基于自适应卷积神经网络的配电网故障识别与定位模型。通过自适应卷积神经网络训练电力数据特征,从而有效提取配电网电力故障特征信息,并基于全连接层对故障进行分... 详细信息

针对目前配电网故障诊断时存在计算时间长、定位精度低的问题,提出了一种基于自适应卷积神经网络的配电网故障识别与定位模型。通过自适应卷积神经网络训练电力数据特征,从而有效提取配电网电力故障特征信息,并基于全连接层对故障进行分类,从而实现端对端的故障检测。通过双端故障定位模型实现故障精确定位。实验结果表明,与DBN模型相比,所提ACNN模型综合性能更优,检测精度提高7.12%时,模型训练时间减少了42.7%。

关键词：配电网故障识别故障定位深度学习

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A highly reliable encoding and decoding communication framework based on semantic information

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Digital Communications and Networks 2024年第3期10卷 509-518页

作者： yichi Zhang Haitao Zhao Kuo Cao Li Zhou Zhe Wang Yueling liu Jibo Wei College of Electronic Science and Technology National University of Defense TechnologyChangsha 410073China

Increasing research has focused on semantic communication,the goal of which is to convey accurately the meaning instead of transmitting symbols from the sender to the *** this paper,we design a novel encoding and decoding semantic communication framework,which adopts the semantic information and the contextual correlations between items to optimize the performance of a communication system over various *** the sender side,the average semantic loss caused by the wrong detection is defined,and a semantic source encoding strategy is developed to minimize the average semantic *** further improve communication reliability,a decoding strategy that utilizes the semantic and the context information to recover messages is proposed in the *** simulation results validate the superior performance of our strategies over state-of-the-art semantic coding and decoding policies on different communication channels.

关键词： Semantic information Semantic encoding method Context-based decoding method

Extended context-based semantic communication system for text transmission

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Digital Communications and Networks 2024年第3期10卷 568-576页

作者： Yueling liu Shengteng Jiang yichi Zhang Kuo Cao Li Zhou Boon-Chong Seet Haitao Zhao Jibo Wei College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China Department of Electrical and Electronic Engineering Auckland University of TechnologyAucklandNew Zealand

Context information is significant for semantic extraction and recovery of messages in semantic ***,context information is not fully utilized in the existing semantic communication systems since re-lationships between sentences are often *** this paper,we propose an Extended Context-based Semantic Communication(ECSC)system for text transmission,in which context information within and between sentences is explored for semantic representation and *** the encoder,self-attention and segment-level relative attention are used to extract context information within and between sentences,*** addition,a gate mechanism is adopted at the encoder to incorporate the context information from different *** the decoder,Transformer-XL is introduced to obtain more semantic information from the historical communication processes for semantic *** results show the effectiveness of our proposed model in improving the semantic accuracy between transmitted and recovered messages under various channel conditions.

关键词： semantic communication extended context Transformer-XL

NEODYMIUM: YAG LASER THERAPY IN APHAKIC PUPILLARY BLOCK GLAUCOMA AND APHAKIC MALIGNANT (CILIOVITREAL BLOCK) GLAUCOMA

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Eye Science 1990年第Z1期15卷 11-16页

作者： yichi liu Wenhui Yang Shaozhen Li Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou, China

Aphakic pupillary block glaucoma and malignant glaucoma (ciliovitreal block) are severe complications of the intracapsular cataract extraction, pesenting clinically as elevated intraocular pressure, persistent shallow anterior chamber and severe vitreal hernia. Six eyes (four women and two men) with aphakic pupi]lary block glaucoma and aphakic malignant glaucoma were resolved by Neodymium: YAG laser iridotomy and hyaloidotomy. The laser therapy resulted in immediate deepening of the anterior chamber and reducing of intraocular pressure. No side effect was observed. Neodymium: YAG laser iridotomy and hyaloidotomy may be more effective and simple than penetrating surgery in such cases.

关键词： glaucoma intraocular cataract penetrating hernia deepening chamber shallow elevated persistent

从2012—2016年国家社科基金立项项目看云南省哲学社会科学发展

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昆明学院学报 2017年第2期39卷 126-132页

作者：刘益池云南省民族艺术研究院艺术科学规划管理小组云南昆明650021

近年来,云南省国家社会科学基金项目立项数呈现稳中有升趋势。以2012—2016年云南省国家社科基金立项项目基础信息为样本,对其立项结构、立项学科、立项项目负责人基本情况等进行统计分析,可知云南省需要加大省级财政投入与管理,注重核... 详细信息

近年来,云南省国家社会科学基金项目立项数呈现稳中有升趋势。以2012—2016年云南省国家社科基金立项项目基础信息为样本,对其立项结构、立项学科、立项项目负责人基本情况等进行统计分析,可知云南省需要加大省级财政投入与管理,注重核心科研人才管理及中青年科研力量培养,加强优劣势学科交叉建设,用活间接经费高效管控项目等。

关键词：国家社科基金项目立项项目立项数量云南省哲学社会科学

地震作用下新疆喀什高台民居基于变形控制的土遗址边坡加固设计研究

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地震工程学报 2024年第2期46卷 388-398页

作者：张一驰刘健杨光新疆农业大学水利与土木工程学院新疆乌鲁木齐830052 新疆新工勘岩土工程勘察设计院有限公司新疆乌鲁木齐830052

为验证地震作用下格构式锚杆挡墙加固土遗址边坡的有效性,以新疆喀什高台民居土遗址边坡现有加固段为研究对象,利用有限元软件Midas/GTX NX建立三维动力分析模型,对地震作用下格构式锚杆挡墙加固土遗址边坡的变形控制进行研究分析。结... 详细信息

为验证地震作用下格构式锚杆挡墙加固土遗址边坡的有效性,以新疆喀什高台民居土遗址边坡现有加固段为研究对象,利用有限元软件Midas/GTX NX建立三维动力分析模型,对地震作用下格构式锚杆挡墙加固土遗址边坡的变形控制进行研究分析。结果表明:地震作用下土遗址边坡在坡顶与坡脚处产生严重的位移变形,且随着地震持时增加呈现累加效果;土遗址边坡加固后能有效控制水平方向与垂直方向的位移变形,最大位移变形值满足控制要求;土遗址边坡加固后地震作用下的稳定性系数提高至1.54,满足规范要求值1.15。研究成果验证了格构式锚杆挡墙加固土遗址边坡能够有效控制位移变形,并提高稳定性。

关键词：土遗址边坡地震格构式锚杆挡墙位移变形稳定性

血耳伴生菌胞外多糖的抗氧化活性及吸湿、保湿性能

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食品研究与开发 2023年第17期44卷 30-36页

作者：何林蔓柳宜池陈莎高梦祥李利长江大学生命科学学院湖北荆州434025 长江大学食品研究院湖北荆州434025

为探讨大型真菌血耳(Tremella sanguinea Peng)的伴生菌的活性物质及其开发利用价值,以血耳子实体中分离得到的伴生菌菌株韧革菌(Stereum sp.)XE02为菌种,利用液态发酵的方法获得发酵液多糖,经脱色、脱蛋白、乙醇沉淀得到胞外粗多糖,得... 详细信息

为探讨大型真菌血耳(Tremella sanguinea Peng)的伴生菌的活性物质及其开发利用价值,以血耳子实体中分离得到的伴生菌菌株韧革菌(Stereum sp.)XE02为菌种,利用液态发酵的方法获得发酵液多糖,经脱色、脱蛋白、乙醇沉淀得到胞外粗多糖,得率为(1.1±0.2)g/L。粗多糖经DEAE-52纤维素柱层析纯化,得到1个中性韧革菌多糖组分(Stereum exopolysaccharides,SEPS)。傅里叶变换红外光谱分析表明,SEPS具有多糖类物质的一般结构特征,单糖组成为吡喃糖,存在α和β两种类型的糖苷键。抗氧化活性分析表明,SEPS具有较好的羟自由基和超氧阴离子自由基清除能力,且呈剂量依赖性,在10 mg/mL时,清除率分别约为68%和74%。SEPS具有良好的吸湿、保湿性能,在相对湿度43%、81%的环境下,SEPS的吸湿率低于甘油,但优于海藻酸钠;在干燥硅胶环境下(相对湿度0%),SEPS保湿率优于甘油和海藻酸钠。

关键词：血耳伴生菌韧革菌胞外多糖抗氧化吸湿保湿