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991.
A neuro-space mapping(Neuro-SM) for modeling heterojunction bipolar transistor(HBT) is presented, which can automatically modify the input signals of the given model by neural network. The novel Neuro-SM formulations for DC and small-signal simulation are proposed to obtain the mapping network. Simulation results show that the errors between Neuro-SM models and the accurate data are less than 1%, demonstrating that the accurcy of the proposed method is higher than those of the existing models. 相似文献
992.
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein. 相似文献
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995.
Matthew E. Ritzman 《Performance Improvement》2016,55(1):14-22
Workplace bullying is a significant problem impacting both individual performance and performance of organizations as a whole. This article describes how a systematic approach was utilized by focusing on the organizational subsystem of human resources as it relates to preventing, identifying, and addressing workplace bullying. Human resource (HR) professionals play a vital role in applying anti‐bullying policies and performance improvement interventions. The article outlines the interventions and policies utilized by HR professionals to alleviate and manage bullying that have been cited in the literature. 相似文献
996.
Lauren H. Howard Annette M. E. Henderson Cristina Carrazza Amanda L. Woodward 《Child development》2015,86(1):259-275
Although children can use social categories to intelligently select informants, children's preference for in‐group informants has not been consistently demonstrated across age and context. This research clarifies the extent to which children use social categories to guide learning by presenting participants with a live or video‐recorded action demonstration by a linguistic in‐group and/or out‐group model. Participants’ (N = 104) propensity to imitate these actions was assessed. Nineteen‐month‐olds did not selectively imitate the actions of the in‐group model in live contexts, though in‐group preferences were found after watching the demonstration on video. Three‐year‐olds selectively imitated the actions demonstrated by the in‐group member regardless of context. These results indicate that in‐group preferences have a more nuanced effect on social learning than previous research has indicated. 相似文献
997.
Mark E. Jonas 《Educational theory》2015,65(1):39-51
While a great deal has been written on Plato's Lysis in philosophy and philology journals over the last thirty years, nothing has been published on Lysis in the major Anglo‐American philosophy of education journals during that time. Nevertheless, this dialogue deserves attention from educators. In this essay, Mark Jonas argues that Lysis can serve as a model for educators who want to move their students beyond mere aporia, but also do not want to dictate answers to students. Although the dialogue ends in Socrates's affirmation of aporia, his affirmation is actually meant to persuade his interlocutors to reflect on an epiphany they had previously experienced. In what follows, Jonas offers a close reading of relevant passages of Lysis, demonstrating the way that Socrates leads his interlocutors to an epiphany without forcing his answers upon them. 相似文献
998.
This study investigated development of the Big Five personality traits from early childhood into adulthood. An initial group of 137 Swedish children were assessed eight times between ages 2 and 29 years. Initial decreases in extraversion leveled off in early adulthood; agreeableness and conscientiousness increased from ages 2 to 29; neuroticism initially increased, leveled off in later childhood and adolescence, and decreased throughout early adulthood; while openness to experience showed an initial increase, then decreased and leveled off in early adulthood. Individual developmental trajectories varied significantly, particularly in relation to gender. Personality traits became increasingly stable, and the fact that childhood scores predicted scores in adulthood indicated that personalities are fairly stable across this portion of the life span. 相似文献
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Video game learning dynamics: Actionable measures of multidimensional learning trajectories 下载免费PDF全文
Debbie Denise Reese Barbara G. Tabachnick Robert E. Kosko 《British journal of educational technology : journal of the Council for Educational Technology》2015,46(1):98-122
Valid, accessible, reusable methods for instructional video game design and embedded assessment can provide actionable information enhancing individual and collective achievement. Cyberlearning through game‐based, metaphor‐enhanced learning objects (CyGaMEs) design and embedded assessment quantify player behavior to study knowledge discovery and application. CyGaMEs is grounded by analogical reasoning theory, cognitive task analysis and knowledge representation. A construct representation argument for validity using evidence‐centered design warrants CyGaMEs, its web‐based learning environment, Selene: A Lunar Construction GaME, its embedded assessment, and a learning dynamics approach to student, measurement and statistical models. Two studies (US volunteers, Study 1: n = 267, mean (M)age = 15; Study 2: n = 90, Mage = 12) cross‐validate learning dynamics (learner progress, rate of progress and changes in that rate) for Selene's multidimensional goals while players learn and apply standard‐based science about fundamental geology and space science concepts. Gameplay data analyzed using regression, calculus and hierarchical linear modeling exhibit overall relatively high standardized rates of progress toward each goal statistically higher than zero. For example, adjusting for nesting within individual players, average rate of progress toward the goal of accreting lunar mass is a z‐score of 1.4 (99% confidence interval = 1.40lower, 1.48upper) or 1.4 standard deviations above zero. 相似文献