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221.
Yangjie Song Chee-Kit Looi 《International Journal of Computer-Supported Collaborative Learning》2012,7(1):129-159
The links uncovered by research connecting teacher beliefs to classroom practice and student inquiry-based learning are tenuous.
This study aims at examining (a) how teacher beliefs influenced practices; and (b) how the influence on practices, in turn, impacted student inquiry learning in a CSCL environment. Through a fine-grained comparative
analysis of two cases, this study explores how two teachers with different collections of beliefs enacted the same mathematics
lesson on division and fractions in a CSCL environment premised on inquiry principles, and what the connections between different
enactments and students’ progressive inquiry process and outcomes were. The findings suggest that the two teachers’ adherence
to different beliefs led to different practices, which in turn contributed to different student learning processes and outcomes.
We interpret these differences that shaped the students’ opportunities for progressive inquiry in the CSCL environment. We
conclude that the teacher holding “innovation-oriented” beliefs tended to enact the lesson in patterns of inquiry-principle-based
practices and technology-enhanced orchestration; these patterns interacted with each other to contribute to student inquiry
learning and effective use of technology affordances. 相似文献
222.
Yong Song Yi-bin Li Cai-hong Li Gui-fang Zhang 《International Journal of Control, Automation and Systems》2012,10(1):166-172
This article demonstrates that Q-learning can be accelerated by appropriately specifying initial Q-values using dynamic wave
expansion neural network. In our method, the neural network has the same topography as robot work space. Each neuron corresponds
to a certain discrete state. Every neuron of the network will reach an equilibrium state according to the initial environment
information. The activity of the special neuron denotes the maximum cumulative reward by following the optimal policy from
the corresponding state when the network is stable. Then the initial Q-values are defined as the immediate reward plus the
maximum cumulative reward by following the optimal policy beginning at the succeeding state. In this way, we create a mapping
between the known environment information and the initial values of Q-table based on neural network. The prior knowledge can
be incorporated into the learning system, and give robots a better learning foundation. Results of experiments in a grid world
problem show that neural network-based Q-learning enables a robot to acquire an optimal policy with better learning performance
compared to conventional Q-learning and potential field-based Qlearning. 相似文献
223.
1 INTRODUCTIONTheorthorhombicalloysareofgreattech nolog icalinterestinhightemperatureapplicationssincetheyhaveagoodbalanceamongst 相似文献
224.
Wang Weihua Xu Wenjie Song Weilin Yang Bin Li Li Guo Xuhong Wu Lianghua Liu Hongxing 《Catalysis Letters》2021,151(8):2326-2338
Catalysis Letters - Novel Mo-V-PMMA and Mo-V-PS catalysts are prepared by addition of hard polymethyl methacrylate (PMMA) and polystyrene (PS) nanospheres into Mo/V compounds in the preparation... 相似文献
225.
Journal of Porous Materials - Nitrogen and oxygen co-doped hierarchical porous carbons (NOPCs) is prepared by the pyrolysis of polyethylene glycol-200 (PEG) and triazine carbon forming agent (CFA)... 相似文献
226.
Youxian Hu Zhenlin Jiang Min Zhu Shiqiang Song Liang Jin Hong Ji Chaosheng Wang Jianhua Wang 《乙烯基与添加剂工艺杂志》2021,27(2):432-444
Polyester is widely used in household products because of its good mechanical properties and wears resistance, but polyester is easy to ignite and inclined to produce droplet, so its application range is limited. The cross-linkable magnesium hydroxide nanoparticles were incorporated into flame-retardant polyester, which enables the phosphorus-containing copolyester with thermal cross-linking and anti-meltdrop properties. The nanoparticles were achieved by in situ polymerization and acted as a nucleating agent for improving the crystalline properties of the copolyester. Furthermore, the nanoparticles also enhanced anti-meltdrop properties and reduced the heat and gas release during the combustion process of the copolyester. The maximum heat release rate and total smoke release reduced by 39.8% and 74.4% compared with pure polyester. Specifically, the combustion products of the nanoparticles and phosphorus flame retardant could act a barrier role by covering the carbon layer to isolate air and heat, thereby resulting in excellent anti-meltdrop properties. The simple modification method reported here realizes the collaborative modification of flame retardant and anti-meltdrop properties of phosphorous flame-retardant copolyesters by thermal cross-linking. 相似文献
227.
Amirah Mohammad-Sidik Jian Sun Ryoung Shin Zhizhong Song Youzheng Ning Elsa Matthus Katie A. Wilkins Julia M. Davies 《International journal of molecular sciences》2021,22(2)
Extracellular ATP (eATP) has long been established in animals as an important signalling molecule but this is less understood in plants. The identification of Arabidopsis thaliana DORN1 (Does Not Respond to Nucleotides) as the first plant eATP receptor has shown that it is fundamental to the elevation of cytosolic free Ca2+ ([Ca2+]cyt) as a possible second messenger. eATP causes other downstream responses such as increase in reactive oxygen species (ROS) and nitric oxide, plus changes in gene expression. The plasma membrane Ca2+ influx channels involved in eATP-induced [Ca2+]cyt increase remain unknown at the genetic level. Arabidopsis thaliana Annexin 1 has been found to mediate ROS-activated Ca2+ influx in root epidermis, consistent with its operating as a transport pathway. In this study, the loss of function Annexin 1 mutant was found to have impaired [Ca2+]cyt elevation in roots in response to eATP or eADP. Additionally, this annexin was implicated in modulating eATP-induced intracellular ROS accumulation in roots as well as expression of eATP-responsive genes. 相似文献
228.
229.
Operational optimization of a building-level
integrated energy system considering
additional potential benefits of energy
storage 下载免费PDF全文
Sai Liu Cheng Zhou Haomin Guo Qingxin Shi Tiancheng E. Song Ian Schomer Yu Liu 《电力系统保护与控制》2021,6(1):55-64
As a key component of an integrated energy system (IES), energy storage can effectively alleviate the problem of
the times between energy production and consumption. Exploiting the benefits of energy storage can improve the
competitiveness of multi-energy systems. This paper proposes a method for day-ahead operation optimization of a
building-level integrated energy system (BIES) considering additional potential benefits of energy storage. Based on
the characteristics of peak-shaving and valley-filling of energy storage, and further consideration of the changes in
the system’s load and real-time electricity price, a model of additional potential benefits of energy storage is
developed. Aiming at the lowest total operating cost, a bi-level optimal operational model for day-ahead operation
of BIES is developed. A case analysis of different dispatch strategies verifies that the addition of the proposed
battery scheduling strategy improves economic operation. The results demonstrate that the model can exploit
energy storage’s potential, further optimize the power output of BIES and reduce the economic cost. 相似文献
230.
研究了13种不同加工热处理制度的Zr-1Nb合金在堆外高压釜内360℃、19MPa水中的吸氢性能,对其影响因素和吸氢机理进行了分析,并讨论了吸氢动力学,建立了吸氢动力学方程,计算了吸氢动力学参数。 相似文献