Assessing students' conceptual understanding using an online three‐tier diagnostic test

When solving a mathematical problem, students who do not have sufficient conceptual understanding may perform poorly and exhibit misconceptions. This study was aimed to examine students' conceptual understanding and significant misconceptions when solving number sense‐related problems. An online three‐tier diagnostic test was administered to 125 fifth‐grade students with varied socio‐economic backgrounds in Hong Kong. Only 14.40% of the students exhibited high performance with high confidence, indicating that these students had a profound conceptual understanding of number sense. In addition, the majority of the students (66.40%) did not demonstrate number sense; these students exhibited several significant misconceptions and could solve the questions only by using a rule‐based method or guessing. Accordingly, most students performed unsatisfactorily on number sense‐related problems. This study is imperative in identifying early predictors and provides information for further compatible interventions in the teaching and learning of number sense in Hong Kong in particular and worldwide in general.     

期刊稿件网络采编系统的建立

《中国冶金》杂志社全面启用的科技期刊稿件采编系统是以Internet为载体，具有作者在线投稿、在线查询、上传校样、专家在线审理稿件、提交审稿意见、上传审改稿、编辑在线加工处理稿件等作用，完全实现了稿件从收稿到发稿的全程数字化管理，同时建立了数据齐全、操作简便的作者、审稿专家和稿件的数据库，改进了传统的操作方法和管理模式，提高了工作效率。杂志社采用该系统还可以进行网刊发布、管理以及期刊征订和发行处理。     

混沌精英哈里斯鹰优化算法

针对哈里斯鹰优化（HHO）算法存在的收敛精度低、收敛速度慢、易于陷入局部最优的不足,提出了一种混沌精英哈里斯鹰优化（CEHHO）算法。首先,引入精英等级制度策略,以充分利用优势种群来增强种群多样性以及提升算法收敛速度和精度;其次,利用Tent混沌映射调整算法关键参数;然后,使用一种非线性能量因子调节策略来平衡算法的开发与探索;最后,使用高斯随机游走策略对最优个体施加扰动,并在算法停滞时,利用随机游走策略使算法有效跳出局部最优。通过对20个基准测试函数在不同维度下进行仿真实验,来评估算法的寻优能力。实验结果表明,改进算法的表现优于鲸鱼优化算法（WOA）、灰狼优化（GWO）算法、粒子群优化（PSO）算法和生物地理优化（BBO）算法,性能较原始HHO算法有明显提升,验证了改进算法的有效性。     

多元醇胺对钢铁渣粉溶解特性的影响

为了解决钢铁渣粉溶解性差所引起的活性低的问题,研究了三乙醇胺( TEA)、三异丙醇胺( TIPA)和二乙醇单异丙醇胺( DEIPA)对钢铁渣粉在碱性环境下溶解的影响规律,通过电导率仪、酸度计、电感耦合等离子体原子发射光谱仪( inductively coupled plasma atomic emission spectroscopy,ICP-AES)和八通道微量热仪对钢铁渣粉的溶解特性进行了表征。结果表明：多元醇胺降低了钢铁渣粉液相的pH并提高了液相电导率,主要表现为增加了液相中Fe、Ca、Al元素的质量浓度,其中TEA和DEIPA的影响效果大于TIPA;多元醇胺提高了钢铁渣粉早期的溶解热和最大水化热峰值,进一步证实了多元醇胺对钢铁渣粉具有增溶作用。     

Compensation of hysteresis in piezoelectric actuator with iterative learning control

This paper presents the application of iterative learning control (ILC) to compensate hysteresis in a piezoelectric actuator. The proposed controller is a hybrid of proportional-integral-differential (PID) control, whose main function is for trajectory tracking, and a chatter-based ILC, whose main function is for hysteresis compensation. Stability analysis of the proposed ILC is presented, with the PID included in the dynamic of the piezoelectric actuator. The performance of the proposed controller is analysed through simulation and verified with experiment with a piezoelectric actuator.     

基于S3C6410的DMA数据跟踪技术在TD-LTE中的实现

基于TD-LTE系统中数据跟踪技术的研究与DMA获取系统总线的不同模式,设计并分析比较了在S3C6410上通过DMA实现原语跟踪的两种方案。根据TD-LTE无线综合测试仪中的设计要求,选择了中断标志查询模式获取系统总线的方案,实现了TD-LTE系统原语的实时跟踪,满足了系统对CPU资源利用率以及数据传输速度和准确性的要求。     

Molecularly imprinted poly(acrylonitrile‐co‐acrylic acid) matrix with sclareol

There are presented results regarding a new set of molecularly imprinted polymers (MIPs) based on acrylonitrile:acrylic acid (AN:AA) copolymer matrix. As template, it was used sclareol, an important anticancer bioactive compound, never used before for molecular imprinting. An emerging and insufficient studied MIP preparation method, namely the phase inversion, was used to prepare 0.8 mm spherical sclareol MIPs (S‐MIPs). Three AN:AA copolymers, having the initial monomer ratios 90:10, 80:20, and 70:30, were synthesized by radical copolymerization in emulsion, without emulsifier. After that, each copolymer was dissolved in the presence of the template (sclareol) in dimethylformamide. The imprinting and the morphology of these new materials were analyzed by rheology, elemental analysis, infrared spectroscopy, size exclusion chromatography, thermogravimetric analysis, differential scanning calorimetry, batch rebinding tests, and Scatchard analysis. The conclusion was that the AN:AA‐80:20 matrix proved to be the optimized solution between high rigidity (given by the AN segments) and high affinity for the template (given by AA segments), the average imprinting factor for this system being 2.67. POLYM. ENG. SCI., 54:1484–1494, 2014. © 2013 Society of Plastics Engineers     

Piezo-Spectroscopic Coefficients of Tetragonal-Prime Yttria-Stabilized Zirconia

The Raman piezo-spectroscopic constants of tetragonal prime yttria-stabilized zirconia under uniaxial compression have been determined. Although the Raman band at 461 cm⁻¹ is not the most intense, it is the most appropriate peak for stress measurement because of its large stress-induced peak shift and the minimum overlap with the other Raman peaks. The peak separation between bands at 258 and 461 cm⁻¹ or 258 and 638 cm⁻¹ can also be used to measure stress.     

The user model-based summarize and refine approach improves information presentation in spoken dialog systems

A common task for spoken dialog systems (SDS) is to help users select a suitable option (e.g., flight, hotel, and restaurant) from the set of options available. As the number of options increases, the system must have strategies for generating summaries that enable the user to browse the option space efficiently and successfully. In the user-model based summarize and refine approach (UMSR, Demberg and Moore, 2006), options are clustered to maximize utility with respect to a user model, and linguistic devices such as discourse cues and adverbials are used to highlight the trade-offs among the presented items. In a Wizard-of-Oz experiment, we show that the UMSR approach leads to improvements in task success, efficiency, and user satisfaction compared to an approach that clusters the available options to maximize coverage of the domain (Polifroni et al., 2003). In both a laboratory experiment and a web-based experimental paradigm employing the Amazon Mechanical Turk platform, we show that the discourse cues in UMSR summaries help users compare different options and choose between options, even though they do not improve verbatim recall. This effect was observed for both written and spoken stimuli.