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.     

基于深度残差学习的自动驾驶道路场景理解

随着道路场景理解技术的快速发展，自主驾驶领域取得了长足的进步。在相关任务中，包括道路分割、分类和车辆检测的实时性和准确性是安全性的一个关键问题。为此，提出了一个具有编/解码器网络结构的基于深度残差学习的方法。一方面，编码器网络结构使用不同层次的残差网络来提取高维中的抽象特征，这些特征在接下来的三个任务中共享使用；另一方面，解码器网络结构采用一种子任务的并行计算机制，即道路分割、车辆检测和道路分类任务同时执行。此外，全卷积神经网络用于对提取的图像特征进行上采样以解决道路分割问题。最终，实验结果表明在保证高精度的前提下处理帧率可达到15 fps以上。     

航空装备保障智能化发展认识与探讨

自新一代人工智能技术迅猛发展以来，世界各国在智能领域动作频繁，军事化应用明显有加速之势，给装备保障带来了变革性发展的机遇。紧密围绕作战-装备-技术-保障之间的依托关系，从作战需求、装备特点、装备设计、诊断测试和技术驱动等五个角度梳理了装备保障发展的关键因素，给出了装备保障60余载发展历程的诸多原因和显著成果；通过对未来作战模式和未来作战平台保障需求的前瞻性判断，分析了未来作战需求和装备牵引装备保障转变的典型技术特征；并在装备保障领域人工智能技术的发展和应用现状总结分析的基础上，系统地提出了装备保障智能化发展的建设性意见和建议，为国内装备保障智能化发展探索了一个可能的技术方向。     

No-reference quality assessment of dynamic sports videos based on a spatiotemporal motion model

This paper proposes an approach to improve the performance of no-reference video quality assessment for sports videos with dynamic motion scenes using an efficient spatiotemporal model. In the proposed method, we divide the video sequences into video blocks and apply a 3D shearlet transform that can efficiently extract primary spatiotemporal features to capture dynamic natural motion scene statistics from the incoming video blocks. The concatenation of a deep residual bidirectional gated recurrent neural network and logistic regression is used to learn the spatiotemporal correlation more robustly and predict the perceptual quality score. In addition, conditional video block-wise constraints are incorporated into the objective function to improve quality estimation performance for the entire video. The experimental results show that the proposed method extracts spatiotemporal motion information more effectively and predicts the video quality with higher accuracy than the conventional no-reference video quality assessment methods.     

一种无线网络优化中挖掘LTE小区场景突变的方法研究

研究了一种检测无线网络优化中挖掘LTE小区场景突变的方法，通过筛选过滤出场景突变的LTE小区数据集，分析确认是否由于某些性能指标或者参数原因而导致的小区场景突变，最终挖掘得到发生场景突变的LTE小区。     

Reviews of clean coal conversion technology in China:Situations & challenges

It is important to develop the advanced coal to chemicals industry (ACCI) against a backdrop of coal-based energy structures,excessive imported oil and natural gas,and strict environmental con-straints in China.In this study,the technology and industry of China's ACCI are reviewed to explain the effect of using coal to replace oil and natural gas,and the corresponding resource and environmental burdens that this will create.Development trends in technology and industry are also proposed to explore future scenarios.The review shows that although excellent progress has been made on an indus-trial scale,demonstrative level,and in terms of technology and equipment,the lack of strategic under-standing,severe external constraints,partly underdeveloped technologies,and weak foundations must be immediately addressed.Therefore,it is necessary to clarify the importance that the ACCI has on the energy revolution and energy system.Based on technological innovation,a variety of external factors should be considered as a whole with emphasis on filling the knowledge gap of theoretical foundations and industry standards to support high-quality development for ACCI.     

CBE教改在职业教育中的应用

通过矿山电气化专业CBE教改过程 ,系统介绍了CBE教改实施情况并提出了自己的建议     

Java3D技术与虚拟现实

当前的虚拟现实建模主要采用OpenGL,VRML等语言,分别存在着难以掌握、不易控制等缺点。为此,针对Java3D语言中对复杂形体构造困难的特点,给出了两种构建方法,充分利用Java语言的面向对象的特征和初学者易学易用的特点来构造虚拟现实场景图。     

规范城市桥梁检测与维修养护工作

从规范城市桥梁检测与维修养护工作全过程出发,对实际工作中的桥粱检测制度及维修养护制度进行了阐述,并针对实际操作过程中出现的问题提出了几点建议。