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161.
黄河流域在中国经济社会发展和生态安全方面具有十分重要的地位。本文基于2005—2017年黄河流域沿线57个城市的面板数据,通过Super-SBM模型测算流域内各城市的绿色发展效率,构建Tobit模型,实证分析黄河流域绿色发展效率的影响因素。研究发现:①全流域的绿色发展效率整体呈现波动上升趋势,上游最高,下游次之,中游最低,效率高值集中在西宁、郑州、西安、太原等省会中心城市和中卫、武威、鄂尔多斯等地区中心城市。②从Tobit回归结果来看,经济发展和产业结构升级可以显著促进黄河流域绿色发展效率的提高,城镇化对黄河流域绿色发展效率的影响呈现“U”型曲线关系,外资利用和科技水平对黄河流域的绿色发展效率有负向影响,环境规制对绿色发展效率的影响不明显。③从各影响因素作用的区域异质性来看,科技水平和外资利用对上游绿色发展效率的影响不显著,经济发展水平对中游的影响有限,而产业结构升级对中游的绿色发展效率有显著的负向作用,外资利用对下游的影响不显著。本文对提升黄河流域的绿色发展水平、助推该地区的高质量发展具有重要意义。 相似文献
162.
一般认为,我国的传统文化在文革时期已全部消亡,不复存在。实际上,从文革时期传唱的歌词看,传统文化中的“礼乐一体”、“乐教”和“集体意识”等特征得以强化甚至发生畸变,“乐教”的宣传教育特征极度彰显,抒情传统退隐淡化。 相似文献
163.
利用达坂城气象站1981-2010年逐年气温、降水和大风资料,分析了近30年来气温、降水及大风的年、季变化特征,结果表明:年均气温总体呈上升趋势,线性倾向率为0.33℃/10a,年1内气温的季节变化存在差异,秋季增温明显,春夏季次之;降水量线性倾向率为9.44mm/10a,气候变湿显著,降水年际变率较大且季节分配不均;Mann-Kendall突变检验表明,气温在1991年发生一次突变,变暖趋势显著,降水在1986年发生由少向多的突变过程;大风日数、平均风速呈现波动下降过程,大风日数线性趋向率为-30.5d/10a,平均风速递减率为-0.76(m/s)/10a,春季大风发生频率最高,为33%,静风频率为10.32%;主导风向以偏西风(WNW)和东南风(SE)为主。 相似文献
164.
高灿钦 《开封教育学院学报》2011,31(4):112-114
1949年中华人民共和国成立,中国共产党实现了由革命党到执政党的"地位转变",并由此开始了与执政地位相适应的"思维方式"的转变,由于阶级斗争思维在执政实践中的过度延伸,到十一届三中全会前,党没能及时实现由传统意义的革命党思维向现代意义的执政党思维转型。改革开放后,随着中国共产党执政意识的理性觉醒,执政党思维方式开始由"革命与斗争"向"建设与整合"全面转型。 相似文献
165.
In previous research, few studies have examined the effects of adolescents’ stress in school on the change rates of their academic achievement. In the present study, we seek to examine the longitudinal relationships between adolescents’ stress in school and the change rates of their academic achievement. The results indicated that for those whose academic achievement significantly declined over time, the students’ stress from teacher–student interaction significantly predicted the change rates of their academic achievement. The findings provided support to the notion that stress was a risk factor in students’ academic development. 相似文献
166.
Social anxiety in learning is prevalent amongst traditional-age students and has a marked effect on their engagement with higher education. It receives little attention from academic or support services and there is a presumption that students will manage their anxieties. Yet it is unclear what psychosocial resources they might bring to this task and how these may develop through the undergraduate years. This study sought to identify possible change processes in student social anxiety by analysing qualitative responses obtained from Level 2 undergraduate students (n=39) in relation to their experience of learning situations such as lectures, seminars and group presentations. Thematic analysis suggested a four-stage developmental progression for students in terms of their experience and orientation to coping with social anxiety. Implications for staff development and student support are outlined. 相似文献
167.
Shyh-ming Lin 《Environmental Education Research》2016,22(5):658-682
This study applied environmental behavioural theories to develop a personal carbon footprint management system and used persuasive technology to implement it. The system serves as an educational system to improve the determinants of students’ low-carbon behaviours, to promote low-carbon concepts and to facilitate their carbon management. To assess the validity of the system, high school students were chosen to participate in an experiment, the results of which reveal (1) the system has significant and positive short-term and relatively long-term effects on the reduction of their self-reported carbon footprint, (2) the system significantly improves their carbon footprint awareness and perceived behavioural control (PBC), and it also promotes behavioural subjective norms, (3) reduction of their self-reported carbon footprint is significantly correlated to PBC, carbon footprint awareness and attitude and (4) PBC is the most critical determinant of carbon reduction. Suggestions are accordingly made. 相似文献
168.
Mustafa Baser 《Journal of Science Education and Technology》2006,15(5-6):367-381
The objective of this research is to investigate the effects of simulations based on conceptual change conditions (CCS) and traditional confirmatory simulations (TCS) on pre-service elementary school teachers’ understanding of direct current electric circuits. The data was collected from a sample consisting of 89 students; 48 students in the experimental group who were taught simulations based on CCS, and 41 students in control group who followed the TCS. Subjects in both groups used open source software (Qucs) to simulate electric circuits. All students were administered Electric Circuits Concepts Test (DIRECT), Science Process Skills Test, Physics Attitude Scale, and Computer Attitude Scale before the treatment. Pre-test analyses revealed that there is no significant difference between experimental and control groups in terms of understanding of direct current electricity. After completing 3 weeks treatment, all students received the DIRECT again as a post-test. Analysis of covariance was used. Science process skills and attitudes toward computers were taken as covariates. The results showed that the conceptual change based simulations caused significantly better acquisition of conceptual change of direct current electricity concepts than the confirmatory simulation. While science process skills and attitudes towards computer made significant contributions to the variations in achievement, gender differences and interactions between gender and treatment did not. Eleven weeks later, the DIRECT was reapplied to the students in both groups. Eleven weeks delayed post-test results showed that the experimental group outperformed the control group in understanding of direct current electric concepts. 相似文献
169.
田运林 《临沂师范学院学报》2010,32(3):47-50
通过对延庆县上辛庄径流试验站两年监测数据的分析,结果表明,植被覆盖度的提高可以明显抑制径流、土壤的流失强度,并且可消弱坡度、降雨对水土流失的影响程度.同时,30%的植被覆盖可能是该区能有效控制水土流失的临界值;污染物的流失强度随植被覆盖度的变化规律与径流与植被覆盖度的变化规律一致,即随着植被覆盖度增加而降低,说明植被措施对污染物流失的控制主要是通过减少径流泥沙而起作用的,但植被措施对不同污染物的抑制效果存在差异. 相似文献
170.
世界经济结构正经历巨大的转型,具体表现为农业所占GDP的比例显著下降,而制造业,尤其是服务业则不断提高.中国、澳大利亚与美国是3个具有代表性的国家,经济上的这种变化对教育以及数学课程都产生了影响,反映了当今社会中对人们所需的"数学素养"的全新要求.中国、澳大利亚与美国义务教育阶段国家级数学课程都强调了"统计思想"与"关系性思维"这两个重要内容. 相似文献