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排序方式: 共有2783条查询结果,搜索用时 31 毫秒
1.
科学评价大学生科研创新能力对我国科研水平的提高具有重要意义.采用机器学习模型来预测大学生科研能力可以起到良好的效果,提出一种GAXGBoost模型来实现对大学生的科研能力预测.此模型是以Xgboost算法为基础,然后充分利用遗传算法的全局搜索能力自动搜索Xgboost最优超参数,避免了人为经验调参不准确的缺陷,最后采用精英选择策略以此确保每一轮都是最佳的进化结果.通过分析表明,所采用的GAXGBoost模型在大学生科研能力预测的结果中具有很高的精度,将此模型与Logistic Regression、Random Forest、SVM等模型进行对比,GAXGBoost模型的预测精度最高.  相似文献   
2.
The article presents a study of face-to-face verbal communication when pupils work with geometry in pairs and share a stand-alone computer with Geoboard software. The work sessions of pairs of 9th grade pupils are video recorded, and a screen recorder is used to capture their computer activity. The study focuses on identifying and characterizing good communication practices that enhance mathematics learning through joint research reflections between the pupils, the teacher, and the researcher. The major finding concerns how two of the pupils have diverging perspectives on how to communicate mathematics, yet they manage to have productive collaboration. The differences generate collaborative challenges for the pupils and an opportunity to discuss how pupils’ communication qualities can prove important in fruitfully managing such challenges.  相似文献   
3.
Lin Huang 《中国物理 B》2021,30(11):114203-114203
A novel organized multipulse pattern and its birth dynamics under strong optomechanical effect in microfiber-assisted ultrafast fiber laser are investigated in this work. The background pulses are observed to obviously exhibit selectively amplifying self-organized process of evolving into quasi-stable equidistant clusters. The radio frequency spectrum of the multipulse pattern displays a harmonic mode-locking-like behavior with a repetition rate of 2.0138 GHz, corresponding to the frequency of torsional-radial (TR2m) acoustic mode in microfiber. The results show the evidence of optomechanical effect in dominating the birth dynamics and pattern of multipulse.  相似文献   
4.
Newly established in 2018, the UK Research and Innovation (UKRI) strengthens the strategic coordination of the UK research and innovation system by bringing together seven Research Councils, Research England, and Innovate UK. Through its nine organizations, UKRI funds multidisciplinary and interdisciplinary research in a number of priority areas. It also runs the Strategic Priorities Fund to support multidisciplinary and interdisciplinary research in strategic areas identified by government policies as well as the Global Challenges Research Fund to promote challenge-led interdisciplinary research needed by developing countries. The UKRI makes significant efforts to engage stakeholders in the development, design, and implementation of multidisciplinary and interdisciplinary programs. It has also developed a range of mechanisms to improve the evaluation of multidisciplinary and interdisciplinary projects. Chinese science and innovation funding agencies could draw upon the UKRI experience from four aspects to advance interdisciplinary research in China.  相似文献   
5.
It has been two months since a boom of online education triggered by the epidemic in China. At present, we are keeping focus on how to optimize our online class. In the case of chemistry laboratory courses, there's not much that can be done to experimental operations through online teaching. While for the traditional teaching procedure, there is still room for improvement in terms of integrating research to teaching, interactivity, etc. This paper will present some design strategies for improving teaching the organic chemistry laboratory online. To be specific, it describes how teaching materials like the lesson plan and virtual lab were coordinated into the online teaching. And we will also discuss the holistic approach to a better outcome for students' active learning and integration research into teaching by redesigning multiple phases, such as the pre-laboratory preparation, live online class, experimental operations.  相似文献   
6.
王诺  丁凯  吴迪  吴暖 《运筹与管理》2019,28(6):118-128
针对若干远海岛礁群系统封闭性的分布特点,将中心岛礁选址、各岛礁建设泊位数量和规模、仓库储存量、运输船型和数量以及航线设置、班期组织等作为规划内容,以整个运输网络系统总成本最低为原则,综合考虑了仓库存储理论,建立了兼顾“选址-库存-路径”的规划模型。结合所建模型特点,提出了双层并行搜索遗传算法,构建了以海上运输为基本交通方式的双向物流系统。最后,以我国南海为例进行建模并求解,采用不同算法并通过多组不同规模的算例进行演算比较,验证了所建模型和算法的有效性与合理性。  相似文献   
7.
The study explored the impact of Please Go Bring Me-COnceptual Model-based Problem Solving (PGBM-COMPS) computer tutoring system on multiplicative reasoning and problem solving of students with learning disabilities. The PGBM-COMPS program focused on enhancing the multiplicative reasoning and problem solving through nurturing fundamental mathematical ideas and moving students above and beyond the concrete level of operation. This is achieved by taking advantages of the constructivist approach from mathematics education and explicit conceptual model-based problem solving approach from special education. Participants were three elementary students with learning disabilities (LD). A mixed method design was employed to investigate the effect of the PGBM-COMPS program on enhancing students’ multiplicative reasoning and problem solving. It was found that the PGBM-COMPS program significantly improved participating students’ problem solving performance not only on researcher developed criterion tests but also on a norm-referenced standardized test. Qualitative and quantities data from this study indicate that, in addition to nurturing fundamental concept of composite units, it is necessary to help students to understand underlying problem structures and move toward mathematical model-based problem representation and solving for generalized problem solving skills.  相似文献   
8.
围绕学校高水平应用型人才培养目标,依托省级重点实验室与省级化学化工大学生创新训练中心等科研教学平台,将“零排放型化学镀镍及其废液资源化为掺杂型LiFePO4/C复合材料”的科研成果进行拆解和提炼,设计为分阶段、多层次的10个教学实验项目,并予以实践。结果表明,该科教融合模式营造出良好的科研氛围,有利于学生科研素养与创新意识的培养、实践能力与创新能力的提升。  相似文献   
9.
《Discrete Mathematics》2022,345(3):112711
We investigate certain nonassociative binary operations that satisfy a four-parameter generalization of the associative law. From this we obtain variations of the ubiquitous Catalan numbers and connections to many interesting combinatorial objects such as binary trees, plane trees, lattice paths, and permutations.  相似文献   
10.
Self-explicated approaches are popular preference measurement approaches for products with many attributes. This article classifies previous self-explicated approaches according to their evaluation types, i.e. trade-off- versus non-trade-off-based, and outlines their advantages and disadvantages. In addition, it proposes a new method, the presorted adaptive self-explicated approach that is based on Netzer and Srinivasan’s (2011) adaptive self-explicated approach and that combines trade-off- and non-trade-off-based evaluation types. Two empirical studies compare this new method with the most popular existing self-explicated approaches, including the adaptive self-explicated approach and paired comparison preference measurement. The new method overcomes the insufficient discrimination between importance weights, as usually found in non-trade-off-based evaluation types; discourages respondents’ simplification strategies, as are frequently encountered in trade-off evaluation types; is easy to implement; and yields high predictive validity compared with other popular self-explicated approaches.  相似文献   
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