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991.
罗雷  黄敏  苏曼 《科教文汇》2011,(32):170-170,175
中介语是用来描述介于二语学习者母语与目的语之间的一种非连续性的语言体系,目前在二语习得研究中日益受到关注。文章以我国英语专业学习者中介语的翻译语料为基础,以学习者中介语的语篇、语用、学习策略等为研究本体,通过多种形式,系统地研究并揭示汉英中介语在英语学习者提高翻译技能的过程中所体现出的发展规律及其影响作用。  相似文献   
992.
As advances in microfluidics continue to make contributions to diagnostics and life sciences, broader awareness of this expanding field becomes necessary. By leveraging low-cost microfabrication techniques that require no capital equipment or infrastructure, simple, accessible, and effective educational modules can be made available for a broad range of educational needs from middle school demonstrations to college laboratory classes. These modules demonstrate key microfluidic concepts such as diffusion and separation as well as "laboratory on-chip" applications including chemical reactions and biological assays. These modules are intended to provide an interdisciplinary hands-on experience, including chip design, fabrication of functional devices, and experiments at the microscale. Consequently, students will be able to conceptualize physics at small scales, gain experience in computer-aided design and microfabrication, and perform experiments-all in the context of addressing real-world challenges by making their own lab-on-chip devices.  相似文献   
993.
Huang CT  Weng CH  Jen CP 《Biomicrofluidics》2011,5(4):44101-4410111
Particle focusing in microfluidic devices is a necessary step in medical applications, such as detection, sorting, counting, and flow cytometry. This study proposes a microdevice that combines insulator-based and metal-electrode dielectrophoresis for the three-dimensional focusing of biological cells. Four insulating structures, which form an X pattern, are employed to confine the electric field in a conducting solution, thereby creating localized field minima in the microchannel. These electrodes, 56-μm-wide at the top and bottom surfaces, are connected to one electric pole of the power source. The electrodes connected to the opposite pole, which are at the sides of the microchannel, have one of three patterns: planar, dual-planar, or three-dimensional. Therefore, low-electric-field regions at the center of the microchannel are generated to restrain the viable HeLa cells with negative dielectrophoretic response. The array of insulating structures aforementioned is used to enhance the performance of confinement. According to numerical simulations, three-dimensional electrodes exhibit the best focusing performance, followed by dual-planar and planar electrodes. Experimental results reveal that increasing the strength of the applied electric field or decreasing the inlet flow rate significantly enhances focusing performance. The smallest width of focusing is 17 μm for an applied voltage and an inlet flow rate of 35 V and 0.5 μl/min, respectively. The effect of the inlet flow rate on focusing is insignificant for an applied voltage of 35 V. The proposed design retains the advantages of insulator-based dielectrophoresis with a relatively low required voltage. Additionally, complicated flow controls are unnecessary for the three-dimensional focusing of cells.  相似文献   
994.
995.
The purpose of this study was to examine (a) the effects of three curricular activities on students'situational motivation (intrinsic motivation [IM], identified regulation [IR], external regulation, and amotivation [AM]) and physical activity (PA) levels, and (b) the predictive strength of situational motivation to PA levels. Four hundred twelve students in grades 7-9 participated in three activities (cardiovascular fitness, ultimate football, and Dance Dance Revolution [DDR]) in physical education. ActiGraph GT1M accelerometers were used to measure students' PA levels for three classes for each activity. Students also completed a Situational Motivation Scale (Guay, Vallerand, & Blanchard, 2000) at the end of each class. Multivariate analysis of variance revealed that students spent significantly higher percentages of time in moderate-to-vigorous PA (MVPA) in fitness and football classes than they did in DDR class. Students reported higher lM and IR toward fitness than DDR They also scored higher in IR toward fitness than football. In contrast, students displayed significantly lower AM toward fitness than football and DDR Hierarchical Linear Modeling revealed that IM was the only positive predictor for time in MVPA (p = .02), whereas AM was the negative predictor (p < .01). The findings are discussed in regard to the implications for educational practice.  相似文献   
996.
人工智能伦理准则与治理体系:发展现状和战略建议   总被引:1,自引:0,他引:1  
首先,界定人工智能伦理准则的基本概念,分析人工智能发展现状。然后,探讨导致人工智能伦理问题的主要原因,总结人工智能典型应用场景下的伦理问题,包括自动驾驶、智能媒体、智慧医疗、服务机器人等;此外,围绕应对人工智能伦理问题的基本原则探索治理框架体系,包括技术应对、道德规范、政策引导、法律规则等方面。最后,结合我国人工智能发展规划战略部署,指出在社会治理的落地过程中宜采取分层次、多维度的治理体系,并提出在人工智能伦理准则和治理方面的具体措施建议(2020-2035年),包括社会宣传、标准体系、法律法规等方面。  相似文献   
997.
利用元分析方法对国内外43篇组织忘却学习与绩效关系的实证研究进行分析,并探讨测量维度、地区文化和中介变量等因素是否会影响二者关系.研究结果表明,组织忘却学习与绩效显著正相关,测量维度、地区文化和中介变量对二者关系有显著的影响,在单维度测量、东方文化背景下或有中介变量存在时,组织忘却学习与其绩效的相关程度更高.  相似文献   
998.
黄传慧 《科技管理研究》2021,41(19):211-216
系统地梳理国外相关文献,旨在把握国外信息搜索行为研究进展,揭示国外信息搜索行为研究视角、研究方法、研究内容和研究趋势,以期为我国信息搜索行为研究提供借鉴和参考.对94篇文献采用综合、归纳、比较等方法进行综合分析,在知识脉络研究部分分研究对象、研究方法、研究内容进行梳理,信息搜索行为研究内容按科研人员、大学生、专业技术人员、其他人群分别进行述评.国外基于工作任务的信息搜索行为研究进展对我国搜索行为研究的启示,一是研究对象上要扩宽;二是在研究方法上寻求突破和创新;三是跨学科合作研究.  相似文献   
999.
地基承载力和地基沉降分析对自升式海洋平台安全作业极为重要.以舟山某海域自升式海洋平台为研究对象,分别采用理论分析和数值模拟的方法对不同入泥深度的桩靴地基承载力和沉降进行计算分析,并开展桩靴几何尺寸对地基承载力影响的敏感度分析.研究结果表明:(1)采用《海洋井场调查规范》理论分析和FLAC3D数值模拟所得到的桩靴安全插桩深度分别为15 m和14 m,结果接近.(2)采用《建筑地基基础设计规范》和FLAC3D数值模拟得到的地基沉降量分别为335.61 mm和260.55mm,相差约28.8%.(3)方形桩靴的长度对地基承载力的影响最大,桩靴长度增加11%,相应的地基承载力增加27%,桩靴高度和桩腿直径对地基承载力影响可以忽略不计.  相似文献   
1000.
Inertial microfluidics has brought enormous changes in the conventional cell/particle detection process and now become the main trend of sample pretreatment with outstanding throughput, low cost, and simple control method. However, inertial microfluidics in a straight microchannel is not enough to provide high efficiency and satisfying performance for cell/particle separation. A contraction–expansion microchannel is a widely used and multifunctional channel pattern involving inertial microfluidics, secondary flow, and the vortex in the chamber. The strengthened inertial microfluidics can help us to focus particles with a shorter channel length and less processing time. Both the vortex in the chamber and the secondary flow in the main channel can trap the target particles or separate particles based on their sizes more precisely. The contraction–expansion microchannels are also capable of combining with a curved, spiral, or serpentine channel to further improve the separation performance. Some recent studies have focused on the viscoelastic fluid that utilizes both elastic forces and inertial forces to separate different size particles precisely with a relatively low flow rate for the vulnerable cells. This article comprehensively reviews various contraction–expansion microchannels with Newtonian and viscoelastic fluids for particle focusing, separation, and microfluid mixing and provides particle manipulation performance data analysis for the contraction–expansion microchannel design.  相似文献   
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