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数据库系统中纵向二维表数据全屏幕编辑程序的设计
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作者 高茂庭 刘积芬 《计算机与现代化》 1997年第1期35-38,共4页
本文介绍了一个在FoxBASE+2.00和FoxPro2.5环境下实现的纵向二维表数据全屏幕编辑处理程序的设计技巧.并介绍了程序实现的具体方法。
关键词 数据库 FOXBASE FOXPRO 纵向二维
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新疆学业水平质量监测汉语试卷的纵向量表化实证研究
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作者 袁硕 彭恒利 《中国考试》 2014年第7期3-9,共7页
作为一种典型的增长模型,纵向量表化(Vertical Scaling,也称垂直等值、垂直标定等)方法常用于评估被试的学业或能力发展状况。本研究以新疆少数民族四至六年级学生在2011年至2013年三次学业水平质量监测汉语考试中的答题数据为样本,采... 作为一种典型的增长模型,纵向量表化(Vertical Scaling,也称垂直等值、垂直标定等)方法常用于评估被试的学业或能力发展状况。本研究以新疆少数民族四至六年级学生在2011年至2013年三次学业水平质量监测汉语考试中的答题数据为样本,采取共同题设计进行数据收集,并运用Thurstone方法和IRT同时标定的方法进行量表分数构建,最终完成了三个年级间的分数连接,实现了对新疆双语班四至六年级学生汉语学业水平增长的测量,为学业水平监测工作提供了可参考的量化指标。 展开更多
关键词 纵向 Thurstone方法 IRT同时标定 学业质量监测
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纵向量表制作浅谈
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作者 刘志明 《考试研究》 2005年第2期76-83,共8页
等值(equating)和纵向量表化(vertical scaling)的功用是建立来自不同考试的分数之间的关系。等值是施用于相同年级,相同性质的试卷,而纵向量表化则用于不同年级而性质相似的试卷。纵向量表化是将不同年级的成绩放置于统一的成长分数量... 等值(equating)和纵向量表化(vertical scaling)的功用是建立来自不同考试的分数之间的关系。等值是施用于相同年级,相同性质的试卷,而纵向量表化则用于不同年级而性质相似的试卷。纵向量表化是将不同年级的成绩放置于统一的成长分数量表之中。纵向量表(vertical scale)是一种延伸的分数,其度量跨越和串连不同年级之间,用以评估学生连继性的成就成长(Nitko,2004)。在教学中,学生的进度可以利用纵向量表来监察和评估。而在教育研究上,纵向量表可成为长期跟踪调查(longitudinal study)之有力工具。本文讨论纵向量表化的方法论,包括成长定义(definition of growth),数据收集(data collection)方法,试卷设计和使用项目反应理论(Item Response Theory)的方法以及对制作纵向量表提供一些实际的建议。 展开更多
关键词 纵向 纵向
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简易纤维形态特征显微显示法
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作者 柯娜 《中国纤检》 1997年第10期26-27,共2页
纺织纤维的鉴别方法有很多种,但对化学结构相似、化学性质接近或相同的纤维,就必须根据其纤维的微细形态结构差别及纤维直径的大小等方面来鉴别检验。若其直径接近,只有依靠其纤维的微细形态结构特征来鉴别。例如:棉和麻类纤维经过加工... 纺织纤维的鉴别方法有很多种,但对化学结构相似、化学性质接近或相同的纤维,就必须根据其纤维的微细形态结构差别及纤维直径的大小等方面来鉴别检验。若其直径接近,只有依靠其纤维的微细形态结构特征来鉴别。例如:棉和麻类纤维经过加工处理后制成的纯棉、纯麻以及棉麻混纺织物时,要想知道织物中的纤维类别及各类纤维的含量,就只有靠分析纤维的微细形态结构来进行鉴别检验。然而未经染色的苎麻、亚麻、大麻纤维的纵向结构在光镜下。 展开更多
关键词 纤维形态特征 微显示 鉴别检验 形态结构特征 混纺织物 鉴别方法 条纹显示 纵向表 纺织纤维 大麻纤维
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得实公司推出家用汉字打印机
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《印刷世界》 1995年第1期42-19,共2页
北京得实公司最近在国内首次推出多功能家用汉字打印机AR3200和AR2100.这种多功能的汉字打印机具有专用数字。
关键词 汉字打印机 国内首次 家用 多功能 高速打印机 彩色打印机 双向打印 计算机 通和断 纵向表
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Effects of continuous casting mould fluxes on reducing longitudinal and star cracks on a slab surface 被引量:1
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作者 WANGQian WANGYu +4 位作者 CHIJinghao XIEBing HEYuming ZHUBing CHENWenman 《Journal of Chongqing University》 CAS 2004年第1期65-68,共4页
In the continuous casting production of medium carbon steel (whose mass fraction of carbon is 0.09 % to 0.16 %) and high strength low alloy steel (whose mass fraction of Mn is 0.90 % to 1.40 %), flecks occurring the m... In the continuous casting production of medium carbon steel (whose mass fraction of carbon is 0.09 % to 0.16 %) and high strength low alloy steel (whose mass fraction of Mn is 0.90 % to 1.40 %), flecks occurring the most often are usually longitudinal and star cracks. In additional to the employment of a galvanized plate mould, two kinds of fluxes with special properties were studied and used to harmonize the conflicts between the function of heat transfer and lubrication. An industrial application revealed that the crystallizing temperature (Tc) and crystal ratio (R) of fluxes have a crucible effect on impeding the occurrence of above defects on a slab surface. In the case of slab section (180 to 240) mm(1000 to 1400) mm and casting speed Vc of (0.7 to 1.2) m/min, the optimized parameters of fluxes are Tc of (1170 to 1190) ℃, R of 80 % to 95 % for medium carbon steel, and Tc of (1100 to 1150) ℃, plus R of 40 % to 60 % for high strength low alloy steel. 展开更多
关键词 continuous casting mould flux star crack longitudinal crack
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The Bipolar Field-Effect Transistor:II.Drift-Diffusion Current Theory(Two-MOS-Gates on Pure-Base)
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作者 薩支唐 揭斌斌 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1849-1859,共11页
This paper describes the drift-diffusion theory of the bipolar field-effect transistor (BiFET) with two identical and connected metal-oxide-silicon-gates (MOS-gates) on a thin-pure-base. Analytical solution is obt... This paper describes the drift-diffusion theory of the bipolar field-effect transistor (BiFET) with two identical and connected metal-oxide-silicon-gates (MOS-gates) on a thin-pure-base. Analytical solution is obtained by partitioning the two-dimensional transistor into two one-dimensional problems coupled by the parametric sur- face-electric-potential. Total and component output and transfer currents and conductances versus D. C. voltages from the drift-diffusion theory, and their deviations from the electrochemical (quasi-Fermi) potential-gradient theory,are presented over practical ranges of thicknesses of the silicon base and gate oxide. A substantial contri- bution from the longitudinal gradient of the square of the transverse electric field is shown. 展开更多
关键词 bipolar field-effect transistor theory MOS field-effect transistor simultaneous electron and holesurface and volume channels surface potential~ longitudinal gradient of transverse electric field
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Human Body Surface Oscillations Remote Measurements by Means of Laser Doppler Interferometer
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作者 Larisa A. Glushchenko Fedor A. Zapryagaev +1 位作者 Vladimir S. Makin Vadim Ya. Krokhalev 《Journal of Mathematics and System Science》 2012年第7期404-408,共5页
Experimental results of remote laser measurement of a time structure of a pulse waves are resulted. Occurrence of the pulse waves are connected with the rhythmic reduction of a myocardittm. Speed of pulse wave's prop... Experimental results of remote laser measurement of a time structure of a pulse waves are resulted. Occurrence of the pulse waves are connected with the rhythmic reduction of a myocardittm. Speed of pulse wave's propagation does not depend on speed of current of blood, it is defined by diameter of a vessel, by its walls thickness, by elasticity of a vessel, and also by rheological properties of blood. Measurement of parameters of pulse waves is important tbr definition of a condition of cardiovascular system. Ways of measurement of characteristics of pulse waves used now (acoustic, electric, optical) are contact. In some cases, for example, in clinics on treatment of burns and so forth, the question of remote measurement of processes hemodynamics by use of methods of laser sotmding is rather actual. The results described in work have shown outlook of development of laser methods of diagnostics for present purposes. The measurement technique used by authors is based on use of longitudinal Doppler effect which essence consists in change of frequency or length of a wave of radiation at reflection from moving surface. For smoothing the measured signal (clearing from noise) the program developed by authors on the basis of the wavelet-analysis was used. Experimental measurements are shown, that the laser method allows to register distinctly structure of pulse waves which is characterized by two peaks. The results of remote laser measurement of a time structure of a pulse waves confirm the assumption made on the basis of general-theoretical physical positions, that characteristics of pulse waves can be registered on the Doppler effect basis. 展开更多
关键词 Pulse wave Doppler effect laser remote methods.
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