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1.
我们从心理语言学的角度,对空间隐喻进行相似性分类和计算,使用多维量表和聚类方法,以聋人为被试分别进行了两个实验。实验结果表明,聋人为实现空间隐喻理解的计算,使用了地形空间和语法空间的特征信息,同时受手语语言特点的影响,其空间隐喻的认知主题包括手势者自身参照系、参照物的相对坐标系、手势空间的饱和度、以手部或胸部为边界。同时表明由于两种空间的存在,聋人大脑对空间隐喻的理解存在着层次,并且在长期使用手语交流的过程中,其地形空间和语法空间相互作用,影响了聋人大脑空间隐喻的结构和表征,从而导致了独特的高效快速空间隐喻计算。
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2.
物理化学多媒体课件的利弊及改进措施   总被引:2,自引:0,他引:2  
随着社会的发展,多媒体教学已经在高校广泛应用起来,计算机已成为教学与科研工作的一个强有力的工具.物理化学以传统的教学方式教学,效果不理想,物理化学多媒体课件在教学中的应用则可以克服以上困难,将抽象的概念蕴含于一些简单明了的动画中,使学生一目了然,同时也促进了学生对物理化学这门课程本身的学习,激发了学生的学习兴趣.本文分析了多媒体教学的优缺点,并指出了相应的改进措施.  相似文献   
3.
Bimetallic Cu/Ni/olivine oxygen carriers (OCs) were prepared using olivine as support material for chemical looping gasification (CLG). The cyclic redox behaviors and oxygen carrying capacity (Ro) of OCs were evaluated by thermo-gravimetric analysis. The effect of Cu/Ni ratio, gasification temperature, steam to biomass ratio (S/B), oxygen carrier to biomass ratio (OC/B) on CLG of cotton stalk has been studied in a fixed bed. The OCs characterized using BET surface area, scanning electron microscopy (SEM), X-ray diffraction (XRD), temperature-programmed reduction (TPR) to investigate the physicochemical property of OCs during CLG. Result shows that the sintering problem of OC was progressively alleviated with the increasing Cu/Ni ratio. The olivine behaves as suitable OC support with oxygen carrying capacity of 1.07%. The redox reactivity of all of the OCs kept well during multiple redox cycles. The Ro of OCs progressively increased with the Cu/Ni ratio. By comparing the product gas concentration, carbon conversion, H2 + CO yield and gas yield over the invested OCs, the Cu9/Ni6/O was found to demonstrate better comprehensive CLG performance due to the synergistic effect of Cu and Ni. The maximum gas yield, H2 + CO yield and carbon conversion with Cu9/Ni6/O can be obtained at the S/B of 0.8 and OC/B of 2. Compared to theoretical value, 65% of lattice oxygen has been supplied by Cu9/Ni6/O during actual CLG process. The OC displayed better reactivity due to basic crystalline phase being preserved well during multiple CLG cycles.  相似文献   
4.
阿里红中多糖的分离纯化及其组分分析   总被引:1,自引:1,他引:0  
目的对阿里红中的多糖进行分离纯化,并对得到的两种多糖组分进行基础结构分析。方法阿里红经水提醇沉法除蛋白后,再经DEAE纤维素-52、Sepharose CL-6B和葡聚糖凝胶Sephadex G-100柱层析分离纯化得到两种多糖组分FOPS-a和FOPS-b。采用凝胶过滤法分析其纯度和相对分子量,经气相色谱法分析其单糖组成,并对多糖组分进行部分酸水解,高碘酸氧化和Smith降解分析。结果分离纯化得到的阿里红多糖组分FOPS-a、FOPS-b的相对分子质量为199 kDa和87 kDa。单糖组成均为甘露糖、阿拉伯糖、半乳糖。FOPS-a主链单糖残基为甘露糖,末端残基和分支单糖残基为阿拉伯糖、半乳糖、甘露糖和鼠李糖;FOPS-b主链单糖残基为甘露糖,末端残基和分支单糖残基为阿拉伯糖、半乳糖、甘露糖和葡萄糖。结论该研究可为阿里红多糖的开发与利用提供技术参考。  相似文献   
5.
A novel rGO/AgCl QDs composites have been obtained by an ultrasonic-assisted method for the first time. Photoelectrocatalytic (PEC) performances of the obtained samples were studied by the degradation of 20 mg/L Tetracycline (TC) under visible light irradiation with an applied bias potential of 1.5 V (vs Ag/AgCl). Degradation of TC by different processes including Photocatalysis (PC), Electrocatalysis (EC), and PEC was compared, and the effect of different bias potential on the PEC degradation of TC was discussed. Results showed that rGO/AgCl QDs composites had displayed superior PEC activity than that of pristine AgCl QDs with degrading 85.2% of TC during 120 minutes, which was about 1.5 times higher than that of AgCl QDs (33%). Besides, compared to PC and EC removal of TC, PEC process showed the highest degradation efficiency of TC (85.2%) by rGO/AgCl QDs, which was about three times and one time higher than that of PC (39.18%) and EC (20.73%) system, respectively. Moreover, the reusibility and stability of the samples were tested by five times cycling tests, and results demonstrated that the stability of bare AgCl QDs was improved after the introduction of rGO. The enhanced PEC activity and stability of the samples could be attributed to the intimate contact between rGO and AgCl QDs and external electric field, which had benefitted the formation of more active sites and accelerated electron-hole separation.  相似文献   
6.
THUUyMorph (Tsinghua University Uyghur Morphology Segmentation Corpus)是由清华大学自然语言处理与社会人文计算实验室构建的维吾尔语形态切分语料库。原始语料从2016年的天山网维文版http: //uy.ts.cn/下载,题材内容包含新闻、法律、财经、生活等。语料库构建步骤为: 爬虫、校对原始语料、分句、校对分句、人工和自动形态切分结合、人工标注语音和谐变化现象、人工校对形态切分和语音和谐变化现象。语料库包含10 596个文档、69 200个句子,词语类型为89 923个,分为词级和句子级两类标注,开源网址为http://thuuymorph.thunlp.org/。该研究不仅对维吾尔语语料库的建设具有参考意义,而且为维吾尔语自然语言处理的研究提供了有益的资源。  相似文献   
7.
分类词谓语是手语中一种独特的语言现象。中国大陆学者对分类词谓语的研究刚开始涉足,尚未见到系统的研究报道。该文试图从语言学的角度对中国手语分类词谓语做了语义认知分析,首先结合Talmy的动态事件和代形词的分析,解释中国手语的分类词谓语现象,分析主体和背景的代形词如何形成以达到手语同时性和序列性要求,并由此确定主体代形词和背景代形词通常是由非运动的手形组成;另一方面也说明中国手语与汉语的相互影响,对“动作”和“位于”这两类的手语代形词做了较为详细的描述及分类。  相似文献   
8.
随着风电技术的发展,双馈风力发电系统高电压穿越问题日益受到研究人员的重视。针对双馈风力发电系统高电压穿越问题,详细分析电网电压骤升时双馈风力发电机运行机理,提出了定子侧变阻值撬棒电路的高电压故障主动穿越方法。对投入撬棒电路后的双馈电机电磁暂态过程进行研究,确定定子撬棒电阻的阻值范围,基于已确定的阻值范围,提出定子侧撬棒保护电路的投切控制策略。最后通过Matlab/Simulink仿真得出双馈风力发电机在电压骤升故障时能更平稳地运转,并且能应对大幅电压骤升故障。验证了定子侧变阻值撬棒电路能够有效完成高电压穿越,提高了双馈风力发电系统的稳定性。  相似文献   
9.
Hierarchical CdS quantum dots (QDs)/ Bi2WO6 three-dimensional (3D) heterojunction photocatalyst was successfully synthesized by a facile green ultrasonic method for the first time. Photocatalytic activities under visible light irradiation were tested by the degradation of Rhodamine B (RhB) and tetracycline hydrochloride (TC), and the reduction of Cr(VI) in aqueous solution. As compared to pure CdS and Bi2WO6, CdS QDs/ Bi2WO6 heterojunctions manifested a significantly enhanced photocatalytic activity for these treatments. When the effect of the mass ratio of CdS QDs to Bi2WO6 was investigated, 3% CdS QDs/ Bi2WO6 heterojunction showed the highest photocatalytic efficiency: the efficiency for RhB degradation was 94.5% for 30?min and this value was about 6 times and 1.5 times higher than those of pure Bi2WO6 and CdS QDs. This enhancement was majorly accredited to the synergetic effect between Bi2WO6 and CdS QDs, which included intimate contact and matched band gap potentials between 0D CdS QDs and 3D Bi2WO6, which contributed to the efficient electron-hole separation and fast transfer of charge carriers between CdS QDs and Bi2WO6. A possible Z-scheme photocatalytic mechanism was proposed, in which the sample was provided with the efficient charge transfer pathway and was endowed with excellent oxidation and reduction ability.  相似文献   
10.
Universal Access in the Information Society - The natural language processing (NLP) of sign language aims to make human sign language “understandable” to computers. In achieving this...  相似文献   
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