电动车能量再生技术

1　Introduction　Therateddistanceisoneofkeyfactorstolimitthedevelopmentofelectricvehicle (EV)sinceEVwasin vented .Itisawayforincreasingtherateddistancetoputtheadvancedenergyregenerationtechnologyintouse .Manyexperimentsprovethattheactualrateddistanceofaelectricscooterunderthecityroadsur roundingsisabout 35 - 45kmwhileitisabout 5 5 - 6 5kmunderthestandard proving ground .Moreover ,JapanToyotaalsoprovedthattherateddistancecouldbeincreasedby 2 0 %whenusingtheenergyregenera tionsysteminEV .Soi…     

How Does the Degree of Guidance Support Students’ Metacognitive and Problem Solving Skills in Educational Robotics?

Educational robotics (ER) is an innovative learning tool that offers students opportunities to develop higher-order thinking skills. This study investigates the development of students’ metacognitive (MC) and problem-solving (PS) skills in the context of ER activities, implementing different modes of guidance in two student groups (11–12 years old, N1 = 30, and 15-16 years old, N2 = 22). The students of each age group were involved in an 18-h group-based activity after being randomly distributed in two conditions: “minimal” (with minimal MC and PS guidance) and “strong” (with strong MC and PS guidance). Evaluations were based on the Metacognitive Awareness Inventory measuring students’ metacognitive awareness and on a think-aloud protocol asking students to describe the process they would follow to solve a certain robot-programming task. The results suggest that (a) strong guidance in solving problems can have a positive impact on students’ MC and PS skills and (b) students reach eventually the same level of MC and PS skills development independently of their age and gender.     

Erosion behavior and mechanism of boronised steels

Boronising of steels is a hardening process to get high surface hardness. The erosion resistance of boronised steels was researched with the use of four kinds of erodent, i.e. glass, alumina, quartz and silicon carbide. The erosion rate increases rapidly with erodent hardness and severe erosion occurs with high impacting angle range of hard particles. SEM analysis indicated that chipping is caused by repetitive impacting of glass and quartz, whereas by alumina and silicon carbide impacting, chipping, and that plastic flow take place simultaneously and the erosion rate reaches the peak value when the impacting angle is above 60°.     

Games for boys: a qualitative study of experiences with commercial off the shelf gaming

Boys are less likely to receive praise and recognition for good schoolwork, to consider school important, and have fewer opportunities to do the things that they do best (Lopez and Calderon in How America’s boys become psychological dropouts. The gallup blog, 2013). Traditional school cultures have come in conflict with the normal and natural ways that boys behave. As a result, boys have had alienating experiences and high levels of disengagement and lowered academic success in school due to rejection of boy culture, which includes aggressive play, competition, and violent fantasy. The purpose of this study was to explore ways in which we can re-engage boys and enhance their learning opportunities in traditional classroom settings. Boys are drawn to video games, which offer a unique environment where they can engage in learning activities. By taking seriously the indigenous knowledge of this portion of boy culture, we may identify ways in which their expertise can become useful towards common learning goals (Carr-Chellman 2007; Carr-Chellman and Savoy 2004). The current analysis represents the first of a multiphase study that uses an interpretive lens within a CHAT framework to identify relevant learning in Commercial of the Shelf (COTS) games. This phenomenological design identifies learning accounts that map to the United States Common Core State Standards. Our findings suggest that engaged learning can occur for these boys as a result of playing games. COTS games engage boys in normal and natural ways, and consequently can be relevant learning tools that educators, researchers and instructional designers might employ toward traditional learning objectives.     

Association between polymorphisms of prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a condition with complex etiologies, to which both genetic and environmental factors may contribute. During the last decade, studies indicated that the expression patterns of the prokineticin receptor (PKR1 and PKR2) are closely related to early pregnancy. However, there are few studies on the role of PKR1 and PKR2 in RPL. In this study, we purpose to investigate the association between polymorphisms of the prokineticin receptor (PKR1 rs4627609 and PKR2 rs6053283) and RPL on a group of 93 RPL cases and 169 healthy controls. Genotyping of the single nucleotide polymorphisms (SNPs) was performed using a Sequenom MassARRAY iPLEX system. The results revealed a significant association between PKR2 rs6053283 polymorphism and RPL (P=0.003), whereas no association was observed between PKR1 rs4627609 polymorphism and RPL (P=0.929) in the Chinese Han population.     

Social network analysis of international student mobility: uncovering the rise of regional hubs

Research on the patterns of international student mobility and the dynamics shaping these patterns has been dominated by studies reflecting a Western orientation, discourse, and understanding. Considering political, economic, cultural, historical, and ecological factors, this study argues that international student mobility is not only an issue of the economically developed, politically stable, and academically advanced Western world but also one that involves countries with different economic, political, and academic characteristics. Taking into account various theoretical orientations, this study argues that political, economic, cultural, and historical factors have led to the emergence of non-traditional destinations for international students; these countries are labeled as emergent regional hubs. In order to empirically test this, a social network analysis was conducted on a worldwide dataset representing 229 countries. The findings evidenced the strong position of traditional destinations for international students. However, the results also suggest the rise of several regional hubs, which are undergoing internationalization processes in different forms and with different rationales. The mobility patterns in emerging regional hubs deviate from those in traditional destinations, which fundamentally change the nature of internationalization in this context.     

Goethe’s Conception of “Experiment as Mediator” and Implications for Practical Work in School Science

There has been growing criticism over the aims, methods, and contents of practical work in school science, particularly concerning their tendency to oversimplify the scientific practice with focus on the hypothesis-testing function of experiments. In this article, we offer a reading of Johann Wolfgang von Goethe’s scientific writings—particularly his works on color as an exquisite articulation of his ideas about experimentation—through the lens of practical school science. While avoiding the hasty conclusions made from isolated experiments and observations, Goethe sought in his experiments the interconnection among diverse natural phenomena and rejected the dualistic epistemology about the relation of humans and nature. Based on a close examination of his color theory and its underlying epistemology, we suggest three potential contributions that Goethe’s conception of scientific experimentation can make to practical work in school science.     

Concurrent and longitudinal predictors of calculation skills in preschoolers

Early calculation abilities in preschoolers are predictive of mathematics achievement in subsequent grades (e.g., Jordan et al. 2009). Two studies were conducted to evaluate concurrent and longitudinal predictors of early calculation skills. In the first study, 102 preschoolers (57.8 % female; mean age?=?60.57?±?8.66 months) were given vocabulary, language comprehension, and verbal working memory tasks and a test battery that evaluated components of early number competence (quantity comparison, counting, number line, size seriation, semantic knowledge of digits, visual-spatial memory). The children were also asked to complete early calculation tasks, including addition and subtraction calculations. The results of this task constituted the dependent variable. The results showed that vocabulary, size seriation, and visual-spatial memory were significant concurrent predictors of early calculation competence. In the second study, 43 children completed the early number competence battery at time 1 (53.5 % female; mean age?=?59.30?±?3.46 months) and the linguistic and early calculation tasks at time 2, about 10 months later (mean age?=?69.43?±?3.31 months). The analysis of the longitudinal predictors of early calculation showed significant effects for counting and size seriation. The implications for preschool assessment and intervention are discussed.     

CPV边界积分的对称数值求积法

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