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The Organizing of Database from Surlari National Geomagnetic Observatory 认领
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作者 Natalia-Silvia Asimopolos Laurentiu Asimopolos +1 位作者 Bogdan Balea Adrian Aristide Asimopolos 《环境科学与工程:A》 2021年第1期26-33,共8页
Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform... Our paper describes the organizing of database,remarks about SNGO(Surlari National Geomagnetic Observatory)and network infrastructure.Based on the geomagnetic data acquired and stored on the database server,we perform the processing and analysis of geomagnetic parameters through different spectral,statistical and correlation methods.All these parameters are included in the geomagnetic database on server.The web interface for the database meets the different needs of handling the data collected,raw or processed.The server-side programming language used for design is php.This allow us to select different periods for which access to stored data,required for different search filters and different parameters or data from different time periods can be compared.For a more in-depth analysis of the stored data,through JavaScript programming language graphs for different parameters can be drawn.Access to the web interface can be done with or without authentication,depending on the need to ensure the security of certain data collected,stored and processed.The applications are scalable for different devices that will access it:mobile,tablets,laptops or desktops. 展开更多
关键词 Geomagnetic observatory DATABASE data in real time data acquisition data processing
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国企收购上市公司股权定价的研究 认领
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作者 吴熙君 《上海管理科学》 2021年第1期46-51,共6页
资本市场是资源合理配置的有效场所。国有企业通过并购重组收购上市公司股权提升资产证券化率,实现国有资产保值增值的目标。国有企业收购上市公司股权过程中,定价是最核心的问题,然而,不确定性资产定价又是非常复杂的事情。对目标企业... 资本市场是资源合理配置的有效场所。国有企业通过并购重组收购上市公司股权提升资产证券化率,实现国有资产保值增值的目标。国有企业收购上市公司股权过程中,定价是最核心的问题,然而,不确定性资产定价又是非常复杂的事情。对目标企业的定价除考虑定价理论和估值方法外,还考虑控制权、流动性、协同效应、支付方式等因素。虽然交易方式更加丰富多样,但从本质上讲,所有方式的背后都会通过定价反映出来。 展开更多
关键词 国企 收购 上市公司 股权 定价 价格 复杂性
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基于TOPSIS法的岸基救助船优选研究 认领
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作者 邹沛霖 《中国海事》 2021年第1期61-65,共5页
船舶发生海难事故,需要选取最适合的救助力量开展救助工作,海上恶劣的环境和搜救时间的紧迫性,对选取救助船有很高的要求。文章以水上人命救助为背景,从岸基专业救助船优选角度出发,分别构建两种模型:层次分析法(AHP)、加权和法相结合... 船舶发生海难事故,需要选取最适合的救助力量开展救助工作,海上恶劣的环境和搜救时间的紧迫性,对选取救助船有很高的要求。文章以水上人命救助为背景,从岸基专业救助船优选角度出发,分别构建两种模型:层次分析法(AHP)、加权和法相结合的优选评价模型,组合赋权、理想解排序法(TOPSIS)相结合的综合评价模型,通过实例将以上两种模型的优选结果与实际结果进行比较,验证了组合赋权-TOPSIS法能够较好的完成优选评价,优选结果与海上实际救助结果相吻合。 展开更多
关键词 船舶优选 理想解排序法 人命救助
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基于FPGA的FTIR光谱仪采集系统的设计 认领
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作者 贾明俊 陆安江 +3 位作者 赵麒 白忠臣 卢学敏 袁钱图 《仪表技术与传感器》 北大核心 2021年第2期47-51,共5页
为了满足人们对于食品药品安全检测快速便携的需要,团队设计一种高速便携,延时低、精度高的新型FTIR光谱仪。光谱采集系统分为上位机和下位机2部分,系统的上位机软件设计是采用跨平台的C++图形用户界面应用程序,该框架(QT Creator)是由... 为了满足人们对于食品药品安全检测快速便携的需要,团队设计一种高速便携,延时低、精度高的新型FTIR光谱仪。光谱采集系统分为上位机和下位机2部分,系统的上位机软件设计是采用跨平台的C++图形用户界面应用程序,该框架(QT Creator)是由编程实现的,下位机的光电部分采用了MEMS微镜使仪器小型化,而下位机采集部分控制主板使用了ZYBO。使用了DAC驱动动镜移动以及ADC用于参考光和样本光数据的同步采集,进而利用多个串口实现了与上位机的完成指令控制以及采集数据传输。低波特率串口用于接收上位机控制指令。2个高波特率串口发送FIFO缓存的光谱数据。经试验验证采集系统的ADC、DAC及UART的时序控制满足了高速高效的需求。但是在便携上可进一步提高,下一步考虑通过利用Linux将上位机部分移植ZYBO内。采集控制设计完全使用了verilog代码进行了仿真与实测,发挥了FPGA的灵活特性,利用例化法提高了采集速率。 展开更多
关键词 FTIR 光谱仪 采集 FPGA ADC DAC UART MEMS ZYBO
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基于条件限定式造句法的中日同形词搭配习得研究——以「深刻」与名词的搭配为例 认领
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作者 王灿娟 《天津外国语大学学报》 2021年第1期92-104,160,共14页
中日同形词的搭配偏误在母语为汉语的日语学习者中较为普遍,但围绕同形词搭配习得的实证性研究却为数不多,且其调查方法均存在一定的局限性。本研究选取形容词-名词型搭配偏误频发的「深刻」,基于笔者设计的条件限定式造句法,调查了母... 中日同形词的搭配偏误在母语为汉语的日语学习者中较为普遍,但围绕同形词搭配习得的实证性研究却为数不多,且其调查方法均存在一定的局限性。本研究选取形容词-名词型搭配偏误频发的「深刻」,基于笔者设计的条件限定式造句法,调查了母语为汉语的日语学习者的搭配习得状况,发现偏误较多的学习者均或多或少地受到了不严谨的日汉词典义项或参考资料解说的影响。为有效防止偏误,有必要对其进行订正和完善,且应充分利用大型语料库及与之相配套的在线搭配检索系统,并构建中日同形词在线搭配词典。 展开更多
关键词 中日同形词 搭配 形容词-名词 习得
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数字资源采购合约核心条款量化研究 认领
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作者 蔺洪全 魏辅轶 吴婷 《图书馆杂志》 北大核心 2021年第1期57-66,共10页
本研究从数字资源采购合约的结构入手,分析当前数字资源采购中图书馆存在的偏好和盲区。进一步论述了学科包条款的成因和重要性,指出"学科包"购买实质上是数据库商的高销售额策略和图书馆追求低成本选择在利益共赢上达成的一... 本研究从数字资源采购合约的结构入手,分析当前数字资源采购中图书馆存在的偏好和盲区。进一步论述了学科包条款的成因和重要性,指出"学科包"购买实质上是数据库商的高销售额策略和图书馆追求低成本选择在利益共赢上达成的一个特定的合约结果。研究分析了11个高校图书馆数字资源采购联盟联合采购的期刊类数据库的合约结构,研究了学科包条款的数量、价格和期刊种类的多样性,并设计了3个指标:自由度F、零整比系数P和重复率系数Q来科学地反映出合约的合理性和科学性,为数字资源合约标准化提供了可以量化的参考标准。 展开更多
关键词 图书馆 合约 数字资源 DRAA 采购 标准 量化 学科包 数据库
获得感视角下的学生党员培养体系探索——“一带一领”工程构建 认领
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作者 余婷婷 《黑龙江生态工程职业学院学报》 2021年第2期110-112,144,共4页
学生党员的培养是基层党组织的一项重要任务,党员培养的质量也关系着党组织的先进性和战斗力。管理学院学生党支部构建从"获得感"角度思考的学生党员培养体系,通过一系列层级式的规范化实践项目,使学生党员参与并投入志愿服... 学生党员的培养是基层党组织的一项重要任务,党员培养的质量也关系着党组织的先进性和战斗力。管理学院学生党支部构建从"获得感"角度思考的学生党员培养体系,通过一系列层级式的规范化实践项目,使学生党员参与并投入志愿服务实践活动,从知识收获、行为规范、体系优化到情感归属的获得感逐渐内化,持续产生正向主观感受,进而坚定理想信念。 展开更多
关键词 获得感 学生党员 培养 坚定信念
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量子定位系统中捕获与粗跟踪控制研究 认领
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作者 丛爽 汪海伦 +1 位作者 邹紫盛 陈鼎 《控制工程》 北大核心 2021年第2期193-199,共7页
首先推导出经过地面站正上方的卫星运行轨道,以及从地面获取的卫星运行轨迹的空间信号函数;然后对整个捕获和粗跟踪过程的控制系统进行离散型模型的建立;采用分行式螺旋扫描捕获策略进行信号捕获,对电流-速度-位置三闭环粗跟踪控制系统... 首先推导出经过地面站正上方的卫星运行轨道,以及从地面获取的卫星运行轨迹的空间信号函数;然后对整个捕获和粗跟踪过程的控制系统进行离散型模型的建立;采用分行式螺旋扫描捕获策略进行信号捕获,对电流-速度-位置三闭环粗跟踪控制系统进行控制器设计,并在Simulink环境下,对卫星经过地面站可见区域的4个不同阶段,分别进行信号捕获及其粗跟踪两轴信号的系统仿真实验,并对不同情况下的捕获与粗跟踪控制性能进行了对比分析。本文所做研究为后续的精跟踪过程和超前瞄准提供了保障。 展开更多
关键词 量子定位系统 粗跟踪 捕获 坐标转换 系统仿真实验
Optimal Grading Policies in the Online Acquisition of Used Products 认领
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作者 Xiang Chu Zhong Wen Jian Chen 《Journal of Systems Science and Systems Engineering》 SCIE EI 2021年第1期29-43,共15页
Although online reverse commerce(recommerce)is convenient and efficient,it is not without caveats.It limits recommerce firms’flexibility to offer personalized prices and may cause mismatched grading between the firms... Although online reverse commerce(recommerce)is convenient and efficient,it is not without caveats.It limits recommerce firms’flexibility to offer personalized prices and may cause mismatched grading between the firms and sellers of used products.This study examines a recommerce firm’s decision on grading criteria and prices.We find that the firm’s optimal policy exhibits two distinctly different patterns depending on the trade value of the product.We demonstrate that sellers’overestimate and underestimate errors have qualitatively different effects on firm profitability,and the effects crucially rely on the type of optimal policy.These findings can apprise firms on how to preset sorting criteria and prices as well as reduce grading errors. 展开更多
关键词 Closed-loop supply chains used-product acquisition management recommerce grading error grading policy
The Interference of First Language in Second Language Learning 认领
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作者 申洁 《海外英语》 2021年第2期110-111,共2页
Second Language Acquisition mainly contributes to the process of second language learning to provide a scientific explanation for language learners’language ability and communicative ability.This paper focuses on the... Second Language Acquisition mainly contributes to the process of second language learning to provide a scientific explanation for language learners’language ability and communicative ability.This paper focuses on the learners whose first language is Chinese and learn English as a second language,and analyzes the interference brought by first language from the perspective of the lexicon,grammar,and cultural differences to analyze the factors causing a negative impact on second language learning. 展开更多
关键词 Second Language Acquisition INTERFERENCE LEXICON GRAMMAR cultural differences
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机载设备离散开关量采集系统设计 认领
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作者 王力 李宏伟 胡先智 《科学技术创新》 2021年第2期115-116,共2页
机载设备使用了大量的离散量信号,作为各系统开关状态信号,利用机载计算机架构,设计了传统和新型的两种离散量采集电路,并根据系统需求配置驱动软件和数据管理软件。该设计可以大大提升离散量采集的可靠性和鲁棒性。
关键词 机载系统 离散量 采集
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文章速递《汉语作为第二语言习得手册》述评 认领
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作者 尹洪山 范琳 《西安外国语大学学报》 CSSCI 2021年第1期45-47,共3页
本文简要介绍了2018年劳特里奇出版社出版的《汉语作为第二语言习得手册》一书的主要内容,并从三个方面对该书的亮点和特色进行了评价。该书以其国际化的研究视角、跨学科的研究范式和应用性的研究取向展示了汉语二语习得研究的最新成果... 本文简要介绍了2018年劳特里奇出版社出版的《汉语作为第二语言习得手册》一书的主要内容,并从三个方面对该书的亮点和特色进行了评价。该书以其国际化的研究视角、跨学科的研究范式和应用性的研究取向展示了汉语二语习得研究的最新成果,对汉语教师和二语习得研究者来说不失为一部极具价值的参考书。 展开更多
关键词 汉语 第二语言 习得 课堂教学
文章速递A Study on Differences between Children’s First Language and Adults’Second Language Acquisition 认领
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作者 周大田 谢山玉 《海外英语》 2021年第5期259-261,264,共4页
Children’s first language(L1)acquisition is generally regarded as natural and effortless.However,adults’second language(L2)acquisition is rather painstaking.The assumption of innate universal language properties,the... Children’s first language(L1)acquisition is generally regarded as natural and effortless.However,adults’second language(L2)acquisition is rather painstaking.The assumption of innate universal language properties,the Universal Grammar and Language Acquisition Device,is proposed to explain the phenomenon of children’s ease in L1 acquisition.The Critical Period Hypothesis or Sensitive Period Hypothesis is also suggested.In terms of the differences in the processes of children’s L1 and adults’L2 acquisition,the following differences are presented:age,motivation,environment,and content.Meanwhile,interference to adults’L2 acquisition is also discussed. 展开更多
关键词 L1 L2 acquisition UG interference
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文章速递Semantics and English Teaching 认领
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作者 段晶 《海外英语》 2021年第6期271-272,共2页
Vocabulary teaching is important but difficult in language acquisition and teaching.Language teachers aims at finding a way to help learners acquire the meaning of words without so much difficulties.With the appearanc... Vocabulary teaching is important but difficult in language acquisition and teaching.Language teachers aims at finding a way to help learners acquire the meaning of words without so much difficulties.With the appearance of semantic theories,it is easy for us to reveal the veil of vocabulary learning.This paper introduces some theories of semantics and their application in vocabulary acquisition and teaching put forward some suggestions for vocabulary pedagogy and teaching strategies. 展开更多
关键词 semantics vocabulary acquisition learning vocabulary teaching
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Fine Doppler shift acquisition algorithm for BeiDou software receiver by a look-up table 认领
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作者 QIU Wenqi ZENG Qingxi +1 位作者 GAO Chang LYU Chade 《系统工程与电子技术:英文版》 SCIE EI CSCD 2020年第3期612-625,共14页
The BeiDou software receiver uses the fast Fourier transform(FFT)to perform the acquisition.The Doppler shift estimation accuracy should be less than 500 Hz to ensure satellite signals to enter a locked state in the t... The BeiDou software receiver uses the fast Fourier transform(FFT)to perform the acquisition.The Doppler shift estimation accuracy should be less than 500 Hz to ensure satellite signals to enter a locked state in the tracking loop.Since the frequency step is usually 500 Hz or larger,the Doppler shift estimation accuracy cannot guarantee that satellite signals are brought into a stable tracking state.The straightforward solutions consist in increasing the sampling time and using zero-padding to improve the frequency resolution of the FFT.However,these solutions intensify the complexity and amount of computation.The contradiction between the acquisition accuracy and the computational load leads us to research for a more simple and effective algorithm,which achieves fine acquisition by a look-up table.After coarse acquisition using the parallel frequency acquisition(PFA)algorithm,the proposed algorithm optimizes the Doppler shift estimation through the look-up table method based on the FFT results to improve the acquisition accuracy of the Doppler shift with a minimal additional computing load.When the Doppler shift is within the queryable range of the table,the proposed algorithm can improve the Doppler shift estimation accuracy to 50 Hz for the BeiDou B1I signal. 展开更多
关键词 fine acquisition fast Fourier transform(FFT) table look-up parallel frequency acquisition(PFA) BEIDOU
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De Novo Organelle Biogenesis in the Cyanobacterium TDX16 Released from the Green Alga <i>Haematococcus pluvialis</i> 认领
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作者 Qinglin Dong Xiangying Xing +2 位作者 Yang Han Xiaolin Wei Shuo Zhang 《细胞生物学(英文)》 2020年第1期29-84,共56页
It is believed that eukaryotes arise from prokaryotes, which means that organelles can form de novo in prokaryotes. Such events, however, had not been observed previously. Here, we report the biogenesis of organelles ... It is believed that eukaryotes arise from prokaryotes, which means that organelles can form de novo in prokaryotes. Such events, however, had not been observed previously. Here, we report the biogenesis of organelles in the endosymbiotic cyanobacterium TDX16 (prokaryote) that was released from its senescent/necrotic host cell of green alga Haematococcus pluvialis (eukaryote). Microscopic observations showed that organelle biogenesis in TDX16 initiated with cytoplasm compartmentalization, followed by de-compartmentalization, DNA allocation, and re-compartmentalization, as such two composite organelles-the primitive chloroplast and primitive nucleus sequestering minor and major fractions of cellular DNA respectively were formed. Thereafter, the eukaryotic cytoplasmic matrix was built up from the matrix extruded from the primitive nucleus;mitochondria were assembled in and segregated from the primitive chloroplast, whereby the primitive nucleus and primitive chloroplast matured into the nucleus and chloroplast respectively. While mitochondria subsequently turned into double-membraned vacuoles after matrix degradation. Results of pigment analyses, 16S rRNA and genome sequencing revealed that TDX16 is a phycocyanin-containing cyanobacterium resembling Chroococcidiopsis thermalis, which had acquired 9,017,401 bp DNAs with 10,301 genes from its host. Accordingly, we conclude that organelle biogenesis in TDX16 is achieved by hybridizing the acquired eukaryotic DNAs with its own one and expressing the hybrid genome. The formation of organelles in cyanobacterium TDX16 is the first case of organelle biogenesis in prokaryotes observed so far, which sheds an unprecedented light on eukaryotes and their connections with prokaryotes, and thus has broad implications on biology. 展开更多
关键词 ORGANELLE BIOGENESIS CYANOBACTERIUM DNA Acquisition Hybridization Transition
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上市公司章程反收购条款之法律界限 认领
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作者 张钰涵 《成都理工大学学报:社会科学版》 2020年第1期46-51,共6页
随着全球市场之自由化、开放化程度不断加深,公司控制权市场逐年升温。“敌意收购”和“反收购条款”,本质上是收购和反收购双方对公司控制权的争夺,是一种商业竞争行为。目前,在中国法律允许的范围内,董事交错条款、金色降落伞条款、... 随着全球市场之自由化、开放化程度不断加深,公司控制权市场逐年升温。“敌意收购”和“反收购条款”,本质上是收购和反收购双方对公司控制权的争夺,是一种商业竞争行为。目前,在中国法律允许的范围内,董事交错条款、金色降落伞条款、超级多数条款是实务中常见的反收购条款。收购人和目标公司控股股东或实际控制人的利益,应当具有相同的价值,他们之间的利益冲突应当在合法公平的环境下,通过商业竞争解决。 展开更多
关键词 收购 反收购 上市公司 公司章程 法律界限
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Application of FPGA in Process Tomography Systems 认领
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作者 Ling En Hong Yusri Bin Md. Yunos 《工程(英文)(1947-3931)》 2020年第10期790-809,共20页
This paper will provide some insights on the application of Field Programmable Gate Array (FPGA) in process tomography. The focus of this paper will be to investigate the performance of the technology with respect to ... This paper will provide some insights on the application of Field Programmable Gate Array (FPGA) in process tomography. The focus of this paper will be to investigate the performance of the technology with respect to various tomography systems and comparison to other similar technologies including the Application Specific Integrated Circuit (ASIC), Graphics Processing Unit (GPU) and the microcontroller. Fundamentally, the FPGA is primarily used in the Data Acquisition System (DAQ) due to its better performance and better trade-off as compared to competitor technologies. However, the drawback of using FPGA is that it is relatively more expensive. 展开更多
关键词 Data Acquisition System (DAQ) Field Programmable Gate Array (FPGA) Application Specific Integrated Circuit (ASIC) Graphics Processing Unit (GPU) MICROCONTROLLER
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A New Electronic Instrumentation Approach for the Acquisition of Microscopic Blood Smear Images for the Automatic Diagnosis of Anemia 认领
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作者 Jerome Nango Alico Sié Ouattara Alain Clement 《生命科学与技术进展(英文)》 2020年第6期237-255,共19页
Anemia is a blood abnormality that affects the quantity and quality of red blood cells in the human body. This sometimes banal sign spares no continent and no social stratum. This anomaly is generally appreciated thro... Anemia is a blood abnormality that affects the quantity and quality of red blood cells in the human body. This sometimes banal sign spares no continent and no social stratum. This anomaly is generally appreciated through biological analyzes of patients</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;"> blood. These analyzes, which boil down to the knowledge of hemato-metric constants, cannot by themselves allow the characterization of certain forms of anemia in the sense that most anemia are related to the morphology and color of red blood cells. Our work in this paper is to perform blood smears on patients and perform a morphological and colorimetric analysis of red blood cells on these smears. This approach allowed us to highlight on each erythrocyte morphological and colorimetric descriptors to accurately identify the types of anemia by image processing methods. This identification is performed in an automated environment to allow pathologists to respond quickly to anemia-related emergencies and also improve the treatment to be conducted. This automation required the implementation of a new approach to electronic instrumentation and the acquisition of microscopic blood smear images for the automatic and rapid diagnosis of anemia. 展开更多
关键词 ANEMIA INSTRUMENTATION ACQUISITION Automated Blood Smears Red Blood Cells Morphological Descriptors Colorimetric Descriptors Image Processing Diagnosis
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The Implications of Krashen's Second Language Acquisition Theory on College English Teaching 认领
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作者 冯勇 《海外英语》 2020年第1期19-20,共2页
Krashen's second language acquisition theory consists of language input theory,emotion filtering theory and languageoutput theory.In order to apply Krashen's second language acquisition theory to college Engli... Krashen's second language acquisition theory consists of language input theory,emotion filtering theory and languageoutput theory.In order to apply Krashen's second language acquisition theory to college English teaching,it is suggested to commence from the acquisition and learning theories to optimize the teaching environment and methods.On the basis of language input theory,emotional filtering theory and language output theory,English input quality could be improved,students'learning interests could be stimulated and English practical teaching could be accelerated respectively. 展开更多
关键词 Krashen’s Second LANGUAGE Acquisition THEORY College English Teaching LANGUAGE Input THEORY EMOTION FILTERING THEORY LANGUAGE Output THEORY
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