有源电力滤波器在谐波治理中的应用分析

阐述了谐波污染对公用电网和其他系统的危害,介绍了谐波抑制和治理的解决方法,重点对有源电力滤波器的应用有关技术进行了分析。     

鄱阳湖微生物资源多样性及药用开发研究进展及策略

研究发现,湖泊环境的微生物中蕴藏着丰富的生物和化学多样性,是创新药物先导化合物的重要源泉。鄱阳湖特殊的地理及气候特征,形成了一个独特的自然环境,生存于其中的微生物必然具备相对独特的分子生物学机制和生理生化特性,它们很可能具有一些不相同的代谢途径和次级代谢产物。因此有必要构建鄱阳湖环境微生物宏基因组文库,探讨微生物的多样性,并从鄱阳湖环境微生物中寻找高新活性先导化合物。     

Information literacy instruction in four Vietnamese university libraries

This case study explored the perceptions of academic stakeholders about the development and delivery of information literacy (IL) programs in four universities, and identified elements necessary to establishing IL credit courses in Vietnamese higher education. The following research questions framed this study: 1) How do library administrators, instruction librarians, and faculty perceive the current implementation of information literacy instruction (ILI) programs for undergraduates studies in universities libraries in Vietnam? 2) What are the challenges to including IL as a credit course in the curriculum as perceived by library administrators, instruction librarians, and faculty? Respondents were purposefully recruited from four universities, including library administrators, instruction librarians, and faculty. Three online surveys were distributed to 537 individuals through Survey Monkey with 149 replies and a final receipt of 133 completed surveys. Interview and focus group data collection included 23 face-to-face interviews and nine focus groups. Findings showed IL is considered the domain of librarians and has not influenced Vietnamese campus culture. IL activities at four university libraries take the form of lectures, workshops, and basic IL skills modules. Few ILI activities are subject discipline-related. Respondents reported challenges to an ILI credit course revolve around the lasting impact of teacher-centered instruction and rote learning, misperceptions about the effect of IL on student learning outcomes, degree of support of IL by academic stakeholders, degree of faculty–librarian collaboration, and scarcity of resources. Recommendations are given for academic librarians in Vietnam implementing ILI programs and considering developing IL credit courses.     

对构建和谐班级的几点感触

一个良好的班集体需要构建和谐的师生关系。新型的师生关系应该是教师和学生在人格上是平等的、在交互活动中是民主的、在相处的氛围上是和谐的．因此，班主任在工作中需要关爱、尊重、研究学生，让学生自主参与，并且改变自己，加强自身修养。     

Active control of structural vibration by piezoelectric stack actuators

INTRODUCTION Passive methods have played an important role for a long time (Snowdon, 1973; Nelson, 1982; Pan et al., 1992) in vibration and noise control. However, with inrush of some novel engineering structures and machines, such as super high-speed machine tools, long-span bridges, thin shell structures, micro elec- tromechanical systems and so on, traditional passive control approaches are not efficient enough for con- trolling structure noise and vibration from these novel systems an…     

Synthesis of acetals and ketals catalyzed by tungstosilicic acid supported on active carbon

INTRODUCTION Acetals and ketals are among the most importantperfume materials and industrial materials of organicsynthesis. There are now many methods to synthesizethem. The H2SO4 conventionally used as catalyst infactories (Li and Fan, 1981) causes many problems,such as erosion of equipment, difficulty for af-ter-treatment, low quality of the products, etc. Withthe use of anhydrous copper sulfate (Hanzlik andLeinwetter, 1978), molecular sieve (Wang and Qian,1993), montmorillonite…     

利用ASP实现网上考试系统

研究了ASP的工作模式和利用ASP访问数据库的关键技术,并在此基础上讨论了一个利用ASP实现网上考试系统的成功实例.     

Non-linear improvement in generic problem-solving skills of university students: a longitudinal study

ABSTRACT

Problem solving has been characterized as one of the ‘employability skills’ due to the high demand for such abilities in a modern workplace. Most universities do not monitor progress of the generic problem-solving skills (PSS) of their students due to a lack of available assessment tools. We used previously reported 15-min tests to measure the generic PSS of students over the first three years of university. More than 600 students participated in this study, including 144 who wrote PSS tests in Year 1 and then again in Year 3 of their studies. Two versions of the PSS test were administered in September and December of both years. We observed a non-linear increase in PSS test scores with a significant growth during the first three months of Year 1, a similar increase over the next 21 months, then no change during the first three months of Year 3. Further studies are necessary to pinpoint the instructional techniques and situational factors facilitating the PSS development of students over the first three years of studies. Moreover, the plateau we observe in the third year indicates that proactive steps by universities and individual instructors are required to advance this important skill set in upper-year students.     

Who is the engaged citizen? Correlates of secondary school students’ concepts of good citizenship

The opinions about what characterises a good citizen are diverse, yet survey research usually employs variable-centred analytical strategies to examine people’s concepts of good citizenship. The present study builds on a person-centred approach towards good citizenship and validates previously identified types of good citizenship among Australian secondary school students. Following an in-depth characterisation of these types by sociodemographic variables and civic attitudes, this study incorporates multinomial regression analysis to take a closer look at very extreme but practically important patterns. These analyses suggest that students need to believe in the value of civic action to become political enthusiasts and not politically alienated. Civic knowledge may prevent political alienation; however, it is not the ultimate solution as it is negatively correlated with political enthusiasm when controlling for multiple predictors. The results are discussed with respect to their significance for civics and citizenship teaching and learning.