结合矩阵分解的混合型社会化推荐算法

推荐系统是用来解决当今时代信息过载的重要工具。随着在线社交网络的出现和普及,一些基于网络推荐算法研究的出现,已经引起研究者的广泛关注。信任是社会网络中的重要信息之一,通常用来改进基于社交网络的推荐系统,然而,大多数信任感知的推荐系统忽略了用户有不同行为偏好在不同的兴趣域;本文不仅考虑了用户间特定域信任网络,并且结合推荐项目之间特征属性信息,提出了一种新型社会化推荐算法(H-PMF)。实验表明,H-PMF算法在评分误差和推荐精度上都取得了更好的效果。     

Exploring teachers' perceptions on different CSCL script editing tools

Despite the apparent maturity of the learning design field, and the variety of tooling available to support it, adoption among the teacher community (one of its alleged main targets) is still low. There is a lack of research on teachers' perception and use of different technological learning design tools, as existing evaluations are often restricted to a single tool. In order to explore whether there are common factors hampering teacher adoption, and which tool features might appeal to different teachers, more studies involving multiple authoring tools are needed. This paper provides a first step in this direction, describing a mixed methods study performed around a professional development workshop with 18 university teachers from multiple disciplines. This workshop exposed teachers to two different authoring tools (WebCollage and EDIT2), as they learned to create computer-supported collaborative learning (CSCL) designs and implement them. The findings of our interpretive study (which included questionnaires, observations, or group discussion recordings) support the idea that there is no single tool or set of features that are globally perceived as better, although our evidence also highlights certain factors as important for participant teachers – amongst others, the integration of learning designs with the ICT platforms for enactment, as well as with other tools that they already use in their everyday practice.     

生物陶瓷人工骨制备的新方法

主要介绍了近年来发展起来的两种新技术 :快速原型制造技术和放电等离子烧结技术。概括了两种技术的原理、特点以及在人工骨制备中的应用 ,提出了用这两种技术制备人工骨的设想。     

Solving a multi-floor layout design model of a dynamic cellular manufacturing system by an efficient genetic algorithm

This paper presents a mixed-integer programming model for a multi-floor layout design of cellular manufacturing systems (CMSs) in a dynamic environment. A novel aspect of this model is to concurrently determine the cell formation (CF) and group layout (GL) as the interrelated decisions involved in the design of a CMS in order to achieve an optimal (or near-optimal) design solution for a multi-floor factory in a multi-period planning horizon. Other design aspects are to design a multi-floor layout to form cells in different floors, a multi-rows layout of equal area facilities in each cell, flexible reconfigurations of cells during successive periods, distance-based material handling cost, and machine depot keeping idle machines. This model incorporates with an extensive coverage of important manufacturing features used in the design of CMSs. The objective is to minimize the total costs of intra-cell, inter-cell, and inter-floor material handling, purchasing machines, machine processing, machine overhead, and machine relocation. Two numerical examples are solved by the CPLEX software to verify the performance of the presented model and illustrate the model features. Since this model belongs to NP-hard class, an efficient genetic algorithm (GA) with a matrix-based chromosome structure is proposed to derive near-optimal solutions. To verify its computational efficiency in comparison to the CPLEX software, several test problems with different sizes and settings are implemented. The efficiency of the proposed GA in terms of the objective function value and computational time is proved by the obtained results.     

列车用CAN协议一致性测试平台的设计与实现

列车用CAN总线协议一致性测试是保证不同设备制造厂家生产的CAN通信设备之间实现互联、互通和互操作的前提。在对协议一致性测试原理和CAN总线协议特点进行简要分析的基础上,提出了针对CAN总线协议一致性测试的协同测试方法和相应的一致性测试内容,设计并构建了相应的一致性测试硬件平台,并对测试软件平台中可执行测试实例产生、测试执行、测试评估以及测试管理等诸多环节所涉及的基本功能软件进行了设计和实现,完成了CAN协议一致性测试的基本功能。实际运行和测试结果表明：所设计的测试平台达到了预期结果,为下一步列车用CAN总线协议的一致性测试打下了基础。     

中药企业MES系统的研发及应用

该文针对中药制造企业计划层与控制层相互脱节的现状,即决策管理层的管理信息如ERP和底层的控制系统(DCS)处于相对独立的状态,在对中药制造企业资源管理现状分析的基础上,利用过程运行信息,以产品产量、质量、节能降耗、过程优化等为目标,研究适合中药制造企业的MES系统,并针对某中药企业做应用研究,证实其有效提高了企业管理水平,并降低能耗.     

以设计为中心的虚拟制造技术及在化工过程装备中的应用

简述了虚拟制造技术的内涵、关键技术及应用现状。在分析化工过程装备特点基础上 ,对过程装备虚拟制造技术平台的体系结构进行了探讨 ,以典型过程装备螺旋片导流式气液分离器为例 ,对其数字化建模方法、数值仿真技术、虚拟设计和制造环境进行了研究。初步结果表明 :以设计为中心的虚拟制造技术的应用 ,可以有效地减少产品开发的时间和成本 ,提高产品质量     

光气生产技术及光气化产品开发进展

综述了光气生产工艺技术、安全措施及主要光气下游产品种类。介绍了国内外光气生产及应用现状，涉及一氧化碳制备、氯气干燥、光气合成、废气处理和安全生产等技术。简述了光气化产品开发研究方向，提出重点开发IPDI(异佛尔酮二异氰酸酯)、NDI(1，5-萘二异氰酸酯)、氯磺酰异氰酸酯和较大分子量的氯代甲酸酯等光气化产品。     

数控技术在机械制造中的发展应用

随着计算机技术的快速发展,数控加工技术凭借精确和高效的优势,已经成为机械制造中的主流技术。主要分析了数控技术的发展现状和特点,并分析了数控技术在机械制造中的应用优势,以促进机械制造业的快速发展。