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201.
供应链上下游企业合作研发模式选择--宝钢-大众激光拼焊项目案例分析 总被引:8,自引:0,他引:8
企业供应链的发展促使企业合作研发寻求新的模式。分析了上下游大型企业进行合作研发的诱因及其模式选择问题,结合宝钢一上海大众激光拼焊案例,重点讨论了建立股权制合作研发对上下游企业的影响和供应链创新的意义。 相似文献
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Students rarely ask questions related to course content in large-format introductory classes. The use of a Web-based forum devoted to student-generated questions was explored in a second-semester introductory biology course. Approximately 80% of the enrolled students asked at least one question about course content during each of three semesters during which this approach was implemented. About 95% of the students who posted questions reported reading the instructor's response to their questions. Although doing so did not contribute to their grade in the course, approximately 75% of the students reported reading questions posted by other students in the class. Approximately 60% of the students reported that the Web-based question-asking activity contributed to their learning of biology. 相似文献
204.
Marital conflict and conduct problems in Children of Twins 总被引:3,自引:0,他引:3
Harden KP Turkheimer E Emery RE D'Onofrio BM Slutske WS Heath AC Martin NG 《Child development》2007,78(1):1-18
The Children-of-Twins design was used to test whether associations between marital conflict frequency and conduct problems can be replicated within the children of discordant twin pairs. A sample of 2,051 children (age 14-39 years) of 1,045 twins was used to estimate the genetic and environmental influences on marital conflict and determine whether genetic or environmental selection processes underlie the observed association between marital conflict and conduct problems. Results indicate that genetic and nonshared environmental factors influence the risk of marital conflict. Furthermore, genetic influences mediated the association between marital conflict frequency and conduct problems. These results highlight the need for quasiexperimental designs in investigations of intergenerational associations. 相似文献
205.
Kohlberg's (1966) hypothesis that the attainment of gender constancy motivates children to attend to gender norms was reevaluated by examining these links in relation to age. Ninety-four 3- to 7-year-old children were interviewed to assess whether and how constancy mediates age-related changes in gender-related beliefs. As expected, results indicated a general pattern of an increase in stereotype knowledge, the importance and positive evaluation of one's own gender category, and rigidity of beliefs between the ages of 3 and 5. Moreover, the stability phase, rather than full constancy, mediated some of these relations. After age 5, rigidity generally decreased with age, with relations primarily mediated by consistency. 相似文献
206.
R. K. Upadhyay S. K. Gaur V. P. Agrawal K. C. Arora 《European Journal of Engineering Education》2007,32(1):21-33
Quality assurance in engineering education is a multifaceted problem further augmented by the stakeholders of engineering education. Students, parents and employers are rightfully questioning the quality of the curriculum, the instructional delivery, the learning environment, accessibility to learning technologies and equipment, employability as well as the possibilities of lifelong learning and the improvement of knowledge (Karapetrovic 2002). The purpose of the study is, therefore, to identify the parameters that influence the quality of an engineering education system and develop an integrated model of hierarchical structuring and a concept map for pre-identified concept elements through a process of iterative-interactive consensus-driven methodology, as advocated by second-generation system design paradigm for evolving knowledge scenario of concepts related to quality engineering education. 相似文献
207.
This study employed an exploratory sequential mixed-methods design to examine the intersection of race and gender among Black American adolescents, aged 11–19. The quantitative component (n = 344) used survey data to examine gender differences in peer-perpetrated and adult-perpetrated racial discrimination experiences, and no gender differences were evident. Qualitative data (n = 42) probed how males and females interpret discrimination experiences given the intersection of race and gender. Although the majority of participants believed that Black males and females have similar experiences, some believed that Black males face more racial discrimination. However, analyses revealed social disadvantages for Black females given that they report inappropriate comments and unwelcome hair touching and limited opportunities for interracial dating compared with Black males. 相似文献
208.
Mariola C. Gremmen Christian Berger Allison M. Ryan Christian E.G. Steglich René Veenstra Jan K. Dijkstra 《Child development》2019,90(2):e192-e211
This study examined to what extent adolescents’ and their friends’ risk behaviors (i.e., delinquency and alcohol use) hinder or promote their academic achievement (grade point average [GPA]), and vice versa. Longitudinal data were used (N = 1,219 seventh- to ninth-grade adolescents; Mage = 13.69). Results showed that risk behaviors negatively affected adolescents’ GPA, whereas GPA protected against engaging in risk behaviors. Moreover, adolescents tended to select friends who have similar behaviors and friends’ behaviors became more similar over time (same-behavior selection and influence). Furthermore, although same-behavior effects seemed to dominate, evidence was found for some cross-behavior selection effects and a tendency in seventh grade for cross-behavior influence effects. Concluding, it is important to investigate the interplay between different behaviors with longitudinal social network analysis. 相似文献
209.
L. DiAnne Borders Laura M. Gonzalez Lindsey K. Umstead Kelly L. Wester 《Counselor Education & Supervision》2019,58(4):293-308
Eighteen new counselor educators shared in‐depth reports of their efforts to establish an early record of scholarly productivity, critical to their success in academe. Analyses of their experiences using consensual qualitative research methods revealed components of both highly positive and highly discouraging program environments and their impact on participants’ research goals. 相似文献
210.
Although widely touted as important, there is little evidence regarding the influence of teaching experience on elementary teachers' science subject matter knowledge (SMK). To better understand this phenomenon, we administered an assessment of science topics taught in the fifth and sixth grades to 169 preservice teachers, 231 fifth-grade teachers, and 208 sixth-grade teachers. We then compared the mean scores of teachers at different stages in the career cycle using one-way and two-way ANOVA and explored the relationship between SMK scores and years of teaching experience using regression analysis. Findings indicate that (i) being assigned to a specific grade level had an impact on teachers' SMK for topics included in the grade level, (ii) teachers' SMK scores were lower later in their careers for both science topics they had never taught and for science topics they were responsible for teaching, and (iii) results differed for fifth and sixth grades. This study adds to the existing literature through the examination of a large sample of elementary teachers, with teachers of varying years of experience, while focusing on the science topics these teachers are responsible for teaching. The results of this study provide strong evidence that (i) years of experience teaching specific science topics is associated with the development of teachers' knowledge of these topics, and (ii) teaching experience, what teachers do in the context of their everyday practice, can be an effective means of self-directed learning for teachers. There is also evidence that this influence is not uniform across years of teaching experience or science topics taught. These findings raise important implications about future research into the mechanism of SMK development through teaching experience and teacher grade-level assignments. 相似文献