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51.
基于Wu-Ritt特征集方法和V.Gerdt的对合除法, 我们定义了非线性偏微分方程组的关于一般延拓方向的对合特征集 (ICS). 影响ICS方法的两个主要因素为: 延拓方向和变量的序. 本文中, 应用ICS方法处理在计算偏微分方程组的对称群过程中产生的大型偏微分方程组. 在实验的基础上, 总结了对于ICS方法较好的延拓方向和变量的序. 相似文献
52.
The Technology Acceptance Model (TAM) is a key model describing teachers' intentions to use technology. This meta-analysis clarifies some of the contradictory findings surrounding the relations within the TAM for a sample of 45 studies comprising 300 correlations. We evaluate the overall fit of the TAM and its structural parameters, and quantify the between-sample variation through meta-analytic structural equation modeling. The TAM fitted the data well, and all structural parameters were statistically significant. On average, the TAM variables explained 39.2% of the variance in teachers' intentions to use technology. Several sample, measurement, and publication characteristics, including teachers’ experience and the representation of the TAM variables, moderated the relations within the TAM. Overall, the TAM represents a valid model explaining technology acceptance—however, the degree of explanation and the relative importance of predictors vary across samples. Implications for further research, in particular the generalizability of the TAM, are discussed. 相似文献
53.
数学建模的思想已经渗入理科各个学科,而数学建模真正走进课堂还需要认真探讨与实践。分析了高等数学教学中结合数学建模思想的重要性与可行性,联系高等数学教学中的一个内容即微分方程问题,探讨了高等数学教学与数学建模的有机结合. 相似文献
54.
管训贵 《青岛职业技术学院学报》2011,24(4):47-48
设p为奇素数,a为整数,若ap-1≡(1mod p2),则a名为费马解。根据华罗庚给出的几个特殊的费马解,可以探求费马解的一般方法。利用初等方法及原根的性质研究同余方程xp-1≡(1modpl),l≥1的可解性,可以得到该同余方程的一切正整数解和费马解。 相似文献
55.
通过线性函数数据建模,以偏微分方程理论为依据,使用Visual C#作为编程设计语言,通过串行通信口送入大量实验数据,并对海量数据进行实证分析,由此获取线性方程的数据建模方法,得到相应程序算法模型,在Visual C#环境下编写程序进行调试分析与测试,并详细介绍了该方法的具体设计过程,给出了关键程序代码,同时给出了利用该方法进行数据处理的一个实例。对于利用采样的海量数据获得线性函数的相关研究有一定的参考价值。 相似文献
56.
BackgroundPrior researches have implicated a relationship of recidivism with childhood trauma (CT) and emotional intelligence (EI). However, the internal mechanism by which CT and EI influence the recidivism has not been examined.ObjectiveThis study aimed to map the road from CT and EI to recidivism in Chinese male offenders.Participants and settingThree thousand one hundred and eighty-one Chinese adult male offenders participated in this study and completed Childhood Trauma Questionnaire (CTQ) and Wong Law Emotional Intelligence Scale (WLEIS). Recidivism was quantified by the number of convictions according to official records.MethodsAfter controlling for age, education levels, family criminal history, and nature of offence, logistic regression sanalysis was performed to examine the effects of CT and EI on severity of recidivism. Structural Equation Modeling (SEM) was applied to explore the mediation model between CT, EI and recidivism.ResultsLogistic regression model shows a significant effect of CT (OR = 1.008, p < 0.01), rather than EI, on recidivism. SEM supported a full mediating effect of CT in the relationship between EI and severity of recidivism.ConclusionsOur findings suggest that EI has no direct effect on the recidivism, but exerts indirect influence on the recidivism through the mediating role of childhood trauma. 相似文献
57.
Georg Krammer Barbara Pflanzl Johannes Mayr 《Assessment & Evaluation in Higher Education》2019,44(4):596-609
Comparing self-perceived quality of teaching to students’ perception can be used in higher education to improve the quality of teaching of pre-service teachers in teacher education. However, comparing these measurements from different perspectives is only meaningful if the same constructs are being measured. To shed light on this comparison’s meaningfulness, we scrutinised whether aspects of quality of teaching are measured in the same way across pre-service teachers and their students by means of measurement invariance analyses. To do so, 272 pre-service teachers in teacher education rated aspects of their quality of teaching, and were rated by their 4851 students. Measurement invariance across these perspectives was tested in multilevel structural equation models. Strong measurement invariance held for two aspects of quality of teaching; for the third, one item lacked weak measurement invariance. Pre-service teachers perceived their quality of teaching lower than their students. In conclusion, aspects of quality of teaching can be compared across perspectives, and teacher education should encourage pre-service teachers to use students’ feedback as a valuable resource for improving their quality of teaching. 相似文献
58.
利用有限差分法求解波动方程边值问题,得到了相应的稳定性分析,并进行了数值模拟.模拟结果表明;该方法求得的数值解有较高的精度和较快的运行速度. 相似文献
59.
Recent privacy-related incidents of mobile services have shown that app stores and providers face the challenge of mobile users’ information privacy concerns, which can prevent users from installing mobile apps or induce them to uninstall an app. In this paper, we investigate the role of app permission requests and compare the impact on privacy concerns with other antecedents of information privacy concerns, i.e., prior privacy experience, computer anxiety, and perceived control. To test these effects empirically, we conducted an online survey with 775 participants. Results of our structural equation modeling show that prior privacy experience, computer anxiety, and perceived control have significant effects on privacy concerns. However, concerns for app permission requests have approximately twice as much predictive value than the other factors put together to explain mobile users’ overall information privacy concerns. We expect that our findings can provide a theoretical contribution for future mobile privacy research as well as practical implications for app stores and providers. 相似文献
60.
Growing evidence suggests that social identities may have profound implications for physical activity participation. Real-world examinations of this relationship have, however, been lacking, with research predominantly examining intentions and hypothetical scenarios. To address this shortcoming and further advance understanding in this area, the present study tested relationships between group identification, participation, two exercise-specific outcomes (exercise-specific satisfaction and group cohesion), and a broad health indicator (life satisfaction) among individuals recruited from parkrun. Participants (N = 289) completed questionnaires measuring all variables except participants’ parkrun participation, which was objectively assessed. Structural equation modeling demonstrated that group identification was significantly associated with greater participation, exercise-specific satisfaction, group cohesion, and life satisfaction. Findings provide real-world evidence of the health-related benefits associated with forming strong social identities in exercise settings. 相似文献