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191.
Gizem Hülür Oliver Wilhelm Stefan Schipolowski 《Learning and individual differences》2011,21(6):742-746
We investigated the usefulness of the Over-Claiming Questionnaire (OCQ) as a measure of cognitive abilities. In OCQs respondents are asked to rate their familiarity with items of academic or everyday knowledge (Paulhus, Harms, Bruce, & Lysy, 2003). Some items exist in reality (reals), and others do not (foils). We developed four OCQs, each consisting of 40 reals and 8 foils from the domains of Science, Humanities and Civics. The OCQs were administered in a longitudinal rotation design to 112 participants who attended the 9th school grade at the beginning of the study. In latent variable regression analyses 53% of variation in the reals could be explained by fluid and crystallized intelligence and over-claiming as indicated by responses to foils. Further variation in responses to reals and foils was explained by intellectual engagement. Our results show that self-reported knowledge, although positively related to measures of ability, to a large extent reflects over-claiming. 相似文献
192.
Leslie Jordan Albert Camille S. Johnson 《Decision Sciences Journal of Innovative Education》2011,9(3):421-436
Many universities are pursuing increases in on‐line course offerings as a means of offsetting the rising costs of providing high‐quality educational opportunities and of better serving their student populations. However, enrollments in online courses are not always sufficient to cover their costs. One possible way of improving enrollments is through marketing campaigns targeted to specific demographic groups. In this study, we take a first look into how students’ perceptions of e‐learning systems, prior to their enrollment in an online course, vary across socioeconomic status and gender. Findings suggest that prior to taking an online course, working‐class students perceive e‐learning systems more positively than their middle‐class peers but that little difference exists between genders. Armed with this knowledge, universities may improve online course enrollments by marketing online courses specifically to working‐class students or through campaigns aimed at improving middle‐class students’ perceptions of e‐learning systems. 相似文献
193.
殷和素 《海南广播电视大学学报》2011,12(3):111-115
信息技术影响到外语教与学的方方面面。对学生进行调查后发现,近半数学生喜欢通过网络和手机等电子工具学习英语;有1/3左右的学生喜欢通过虚拟学习环境学习英语;只有很少一部分学生喜欢去自主学习中心学习英语。从学生视角对造成上述现象原因进行分析有助于帮助学生提高学习能力。 相似文献
194.
陈训先 《韩山师范学院学报》2011,32(2):6-9
该文根据国家权威档案文献,论述1860年汕头开埠始末的曲折过程;指出,汕头开埠是第二次鸦片战争清政府屈辱妥协外交路线的产物,是中华民族的屈辱史,是粤东门户被迫"开放"史,也是潮汕历史大走向的重要转折点。今人应以胡乔木《国史事典》的题词"在沉重的历史中,汲取奋进的力量"为警示,"知耻近于勇",爆发奋进之力,建设美好家园。 相似文献
195.
庄承州 《韩山师范学院学报》2011,(6):17-21
设G=(V,E)是一个图,G的Geometric—Arithmetic指数(简称GA指数)在某些化学物品的物理性质方面具有良好的预测作用.通过计算,给出了直链、锯齿链四角系统和转向细胞个数为1的链状四角系统的GA指数公式;证明了六角系统中完全冷凝苯类的GA指数是其转向六边形个数和分枝六边形个数的单调递增函数. 相似文献
196.
Radar cross section (RCS) of non-spherical raindrops is calculated by using the software CST based on finite integral method
and compared with RCS of spherical raindrops. The revised factor of non-spherical raindrops is obtained. The radar reflectivity
with precipitation change of four distribution models of M-P, Gamma, JD and JT combining the revised factor is gotten using
trapezoidal integration. When the influence of non-spherical raindrops is considered, the accuracy of precipitation measurement
of four distribution models can be separately improved 8.77%, 8.47%, 10.53% and 8.04% in the case of rain intensity is 100
mm/h. 相似文献
197.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering
method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction
(XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence
of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the
resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film. 相似文献
198.
This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6... 相似文献
199.
张娟 《上海大学学报(英文版)》2011,15(1):31-34
A novel flat-top and low-dispersion optical interleaver using ring cavities (RCs) in a Mach-Zehnder interferometer (MZI) is proposed. It is composed of eight mirrors and two nested prism pairs. Each prism and the two mirrors behave as a RC. Phase shift of RC is a periodic function of the frequency of the input light which acts as a phase dispersive mirror. The two phase shifts needed to achieve a flat-top spectral passband are provided by Fresnel reffectivities at the prism-air interface of the two RCs. The... 相似文献
200.
Depth maps are used for synthesis virtual view in free-viewpoint television (FTV) systems.When depth maps are derived using existing depth estimation methods,the depth distortions will cause undesirable artifacts in the synthesized views.To solve this problem,a 3D video quality model base depth maps (D-3DV) for virtual view synthesis and depth map coding in the FTV applications is proposed.First,the relationships between distortions in coded depth map and rendered view are derived.Then,a precisely 3DV quali... 相似文献