Finite element modeling of superplastic co-doped yttria-stabilized tetragonal-zirconia polycrystals     

Hsuan-Teh Hu  Shih-Tsung Tseng  Alice Hu 《浙江大学学报(A卷英文版)》2016,17(12):989-999

Yttria-stabilized tetragonal-zirconia polycrystals (Y-TZP) have been shown to have superplastic properties at high temperatures, opening a way for the manufacture of complex pieces for industrial applications by a variety of techniques. However, before that is possible, it is important to analyze the deformation and fracture mechanisms at a macroscopic level based on continuum theory. In this paper, an elastic-plastic material model with a theoretical large deformation is constructed to simulate the true stress-true strain relationships of superplastic ceramics. The simplified constitutive law used for the numerical simulations is based on piecewise linear connections at the turning points of different deformation stages on the experimental stress-strain curves. The finite element model (FEM) is applied to selected tensile tests on 3-mol%-Y-TZP (3Y-TZP) co-doped with germanium oxide and other oxides (titanium, magnesium, and calcium) to verify its applicability. The results show that the stress-strain characteristics and the final deformed shapes in the finite element analysis (FEA) agree well with the tensile test experiments. It can be seen that the FEM presented can simulate the mechanical behavior of superplastic co-doped 3Y-TZP ceramics and that it offers a selective numerical simulation method for advanced development of superplastic ceramics.  相似文献   

Cultural conflicts of the child‐centered approach to early childhood education in Taiwan     

I‐Fang Lee  Chao‐Ling Tseng 《Early Years: An International Journal of Research and Development》2008,28(2):183-196

This paper discusses the cultural conflicts around the Western notion of child‐centeredness in Taiwanese preschools. The implementation and translation of Developmentally Appropriate Practice (DAP) in Taiwan is highlighted as an example to understand productions of differences, norms and cultural conflicts in Taiwanese early childhood education. Throughout this paper, it is argued that multiplicities and differences are not acknowledged but instead are dangerously ignored while assumptions are made about a singular norm and homogeneous universal standard. From this perspective, it is asserted that the global circulation of a particular Western notion of child‐centeredness should be (re)conceptualized as a cultural construct through which a particular system of reasoning or cultural knowledge is perpetuated.  相似文献   

How to Help Teachers Develop Inquiry Teaching: Perspectives from Experienced Science Teachers     

Chung-Hsien Tseng  Hsiao-Lin Tuan  Chi-Chin Chin 《Research in Science Education》2013,43(2):809-825

This study has two purposes: the first is to explore experienced science teachers’ perspectives on inquiry teaching, and the second is to categorize these perspectives into patterns. Fifteen junior high school science teachers experienced at inquiry teaching were selected, and a semi-structured interview was conducted to collect the teachers’ perspectives on inquiry and inquiry teaching. The findings indicate that these experienced science teachers hold multiple perspectives on inquiry and inquiry teaching. The two patterns generated from these teachers’ perspectives of inquiry and inquiry teaching were systematic-based inquiry instruction and learning-based inquiry instructions. Suggestions for science teacher educators are discussed in this paper.  相似文献   

Distance Learners' Self-efficacy and Information Literacy Skills     

Yingqi Tang  Hung Wei Tseng 《The Journal of Academic Librarianship》2013

This study investigates distance learners' information literacy skills in using digital library resources and the factors (online learning and information manipulation) that correlate with learners' information seeking self-efficacy. In addition, distance learners' preferences with regard to digital resources selection and interests of developing information seeking skills were examined. 3517 students enrolled in one or more distance education courses were invited to participate in the online survey; 219 students completed the survey, for a response rate of 6.2%. The results revealed that distance learners who have higher self-efficacy for information seeking and proficiency in information manipulation exhibited higher self-efficacy for online learning. Moreover, students with high self-efficacy demonstrated superior knowledge of digital resources selection. Students who have low self-efficacy with regard to information seeking were more likely to express interest in learning how to use the library resources, although learning techniques for database searching was the exception.  相似文献   

Unpacking immigration in youths' academic and occupational pathways     

Tseng V 《Child development》2006,77(5):1434-1445

This study sought to unpack how immigration is associated with youths' educational choices during the transition to college and adulthood. Surveys and school records were collected on 789 youth (ages 18-25) with Asian Pacific, Latino, African/Afro-Caribbean, and European backgrounds. The results indicated generational differences in educational choices, such that children of immigrants chose courses of study with higher math and science content than that of their peers with U.S.-born parents. Mediation analyses indicated that children of immigrants reported higher social and economic aspirations than did their peers, and their economic aspirations accounted for part of the generational difference in educational choices. Generational differences in educational choices were also mediated by verbal achievement test scores and perceived English skills.  相似文献   

How to promote knowledge transfer through a problem-based learning Internet platform for vocational high school students     

Shi-Jer Lou  Kuo-Hung Tseng  C. Ray Diez  Huei-Yin Tsai 《European Journal of Engineering Education》2010,35(5):539-551

This study aimed to explore how vocational high school students transfer knowledge through a problem-based learning (PBL) Internet platform. A PBL Internet platform was provided to 33 sophomore mechanical engineering students for a 6-week teaching experiment. A survey questionnaire, observation and interview were research instruments. The findings include: 1) factual, conceptual and process knowledge are the major types of knowledge and the sources of knowledge transfer (KT) include students, instructors and industries, but may be acquired differently depending on the level of problem-solving needs; 2) students’ KT includes highly experienced tacit knowledge and more concrete explicit knowledge; 3) students’ attitudes toward the six domains of using the PBL Internet platform all show positive significance, including the platform, the platform instructors, the platform mobility, online interaction, the PBL and the platform interface mechanism of students’ perceptions; 4) the capability and the willingness for KT in instructors, industries and students all have some impact on the effectiveness of KT.  相似文献   

The geographic accessibility and inequality of community-based elderly learning resources: a remodeling assessment, 2009–2017     

Ming-Hseng Tseng 《Educational gerontology》2018,44(4):226-246

Continuous elderly learning activities not only empower elderly populations’ knowledge about health but also enhance these populations’ social connections and social abilities, which can enhance their overall quality of life. Geographic accessibility is a determinant factor for elderly participation in social activities. In this study, we proposed six measurement methods and employed the Gini coefficient to discuss the geographic accessibility and geographic inequality of community-based elderly learning resources. This study provides three methodological contributions for future research. First, we propose an origin–destination cost matrix analysis that incorporates a post-pruning technique. Applying this technique allows for the consideration of policy restrictions in relation to resource utilization. This approach also contributes to the ability to obtain a reliable assessment of the accessibility of resources. Second, this study proposes a new, more direct and convenient, method of calculating the Gini coefficient. Third, we find that the different distance-decay index β indicates the impact of distance factors on the efficiency of resource utilization. The distance-decay index β should carefully discern when distance is under 1 km. These results indicate that assessing accessibility does not only consider length and traffic distance but also requires a deliberate and weighted calculating process depending on the distance, elderly demand population, and supply capacities of learning centers. Although our study focuses on Taiwanese cases, our methodologies and results illustrate possibilities for other contributions that assess geographic accessibility and resource-allocation inequality for elderly learning policy planning and implementation.  相似文献   

泰国兔儿风属(菊科)一新种     

程用谦 《中国科学院研究生院学报》1988,26(1):74-75

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中国胡椒属新分类群     

程用谦 《中国科学院研究生院学报》1986,24(5):382-386

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A study on customer,supplier, and competitor knowledge using the knowledge chain model     

Shu-Mei Tseng 《International Journal of Information Management》2009

In the new economy, firms are willing to pay abundant premiums for the significant entrepreneurial capacities of management and staff in order to develop, build, protect, transfer and integrate knowledge. Although companies and scholars have indeed recognized the value of knowledge management, they have not generally included customer, supplier, and competitor knowledge, preferring to emphasize the process of knowledge acquisition and sharing that takes place within organizations. Thus, this study proposes a conceptual framework, and uses interpretative case studies, to explore how an enterprise obtains the three types of external knowledge. Moreover, through the following five primary activities – acquisition, selection, generation, internalization, and externalization – this study will illustrate how enterprises apply the internal knowledge chain to transform their customer, supplier, and competitor knowledge to enhance enterprise competitiveness.  相似文献