针对信息安全专业《近世代数》课程改革的探讨

针对信息安全专业的《近世代数》教学,分析信息安全专业学生与数学专业学生在《近世代数》学习上存在的差异性,并因此提出如何调整《近世代数》的教学内容使其更适合信息安全专业学生的学习,探讨针对信息安全专业《近世代数》学习的教学方法改革,从而提高信息安全专业学生学习《近世代数》的积极性和效果。     

精确实验数据曲线方程的求解

针对精确实验数据的曲线拟合方程化处理方法已不再适应高精度测试技术的问题,提出了用三次样条插值函数进行曲线方程化处理的新方法,并创建了用MATLAB语言编写遗传算法程序进行曲线斜率求解的方法,通过实例表明,采用遗传算法求解出的三次样条插值函数非常适合精确实验数据的曲线方程化处理。     

Radial gas mixing in a fluidized bed using response surface methodology

Radial gas mixing in a fluidized bed was studied using response surface methodology (RSM), which enables effect examinations of parameters with a moderate number of experiments. All experiments were conducted in a 0.29-m ID fluidized-bed cold model. The gas dispersion process within the bed is described using the dispersed plug flow model. Pure carbon dioxide was used as the tracer gas, continuously injected into the center of the bed by a point source. The downstream radial tracer concentration profile was measured using a gas chromatograph.The radial gas dispersion coefficient, D_r, was well correlated with operating parameters and the particle and gas properties: (U−U_mf)/U_mf, H_s/d_b, φ_d, and Ar, with a determination coefficient R² of 0.966. Effect test indicates that the dimensionless characteristic velocity, (U−U_mf)/U_mf, has the most significant influence on D_r, while the static bed height to bed diameter ratio, H_s/d_b, is less remarkable. The interactions of (U−U_mf)/U_mf with the distributor open-area ratio, φ_d, and with the Archimedes number, Ar, both play important roles. An evolutive response surface model was proposed to describe the radial gas mixing in the bubbling/slugging fluidization regimes.     

Water uptake and tensile properties of carboxylated styrene butadiene rubber based water born paints: Models for water uptake prediction

Despite significant advances in water based surface coating technology, the presence of surfactants in emulsion polymer binders leads to loss of performance after prolonged immersion in water, relative to solvent based coatings that are free of surfactant impurities. This study begins with water uptake evaluation of a range of emulsion polymer binders. A carboxylated styrene butadiene rubber latex (c-SBR) performed best in the latter evaluations and was selected for the formulation of an exterior grade paint and construction of a mathematical model to predict water uptake of the dry film. The c-SBR was then compounded with a range of inorganic fillers and water uptake and tensile properties were evaluated. Talc was found to be the best performing filler, and was used in a three factorial central composite design study where the simultaneous effects of talc, titanium dioxide and phenolic stabiliser on water up take were evaluated and fitted to response equations. A quadratic model was found to provide the most accurate prediction of effects associated with interactions between talc and TiO₂. Certain combinations of talc and titanium dioxide were found to be synergistic in reducing the water uptake. This was considered to be associated with a packing effect stemming from the vast difference in particle size between talc and titanium dioxide particles. An optimised formulation was finally prepared to meet one of the final formulation objectives; i.e., minimised water uptake. Preparation of such a formulation showed that the predicted and measured water uptake responses were in excellent agreement. This study illustrates the effectiveness of statistical experimental design methods in predicting the water uptake characteristics of water-based coatings.     

End-User Development of Mashups with NaturalMash

Context: The emergence of the long-tail in the market of software applications is shifting the role of end-users from mere consumers to becoming developers of applications addressing their unique, personal, and transient needs. On the Web, a popular form of such applications is called mashup, built out of the lightweight composition of Web APIs (reusable software components delivered as a service through the Web). To enable end-users to build mashups, there is a key problem that must be overcome: End-users lack programming knowledge as well as the interest to learn how to master the complex set of Web technologies required to develop mashups. End-User Development (EUD) is an emerging research field dealing with this type of problems. Its main goal is to design tools and techniques facilitating the development of software applications by non-programmers.Objective: The paper describes the design and evaluation of NaturalMash, an innovative EUD tool for mashups (a mashup tool). NaturalMash aims at enabling non-professional users without any knowledge of programming languages and skills to create feature-rich, interactive, and useful mashups.Methods: The design of NaturalMash adopts a formative evaluation approach, and has completed three design and evaluation iterations. The formative evaluations utilize usability testing, think aloud protocol, questionnaires, observation, and unstructured interviews. Additionally, we compare the expressive power of naturalmash with the state-of-the-art mashup tools.Results: The results from the formative evaluations helped us identify important usability problems. From an assessment point of view, the results were promising and sggested that the proposed tool has a short and gentle learning curve in a way that even non-programmers are able to rapidly build useful mashups. Also, the comparative evaluation results showed that NaturalMash offers a competitive level of expressive power compared with existing mashup tools targeting non-programmers.Conclusion: As the evaluation results indicate, NaturalMash provides a high level of expressive power while it is still highly usable by non-programmers. These suggest that we have successfully achieved the objective of the proposed tool, distinguishing it from existing mashup tools that are either too limited or highly specialized for non-professional users.     

计算机网络课程实验教学设计的研究

实验教学是计算机网络课程的不可缺少的一部分,是提高学生分析解决问题能力和实际动手能力的重要途径。针对实验教学中存在的问题,对计算机网络实验课程的学情、教学目标,教学内容、教学过程和教学评价进行分析和设计,力图扩大知识面,完善实验教学环节,提高学生学习兴趣,改善教学效果。     

顾桥煤矿东风井冻结粘土本构关系实验研究

我国两淮矿区分布深厚粘土层,矿井建设一般采用冻结法施工,冻结粘土的物理力学性能是决定冻结法参数选择的主要因素,因此以顾桥煤矿东风井深厚粘土层为研究对象,找到冻土在单轴应力条件下的应力、应变、温度和时间相互作用的关系,并照C．C．维亚洛夫推荐公式,运用统计的方法,推导出冻结粘土的本构方程。该方程在两淮矿区冻结井壁的强度和变形进行理论计算和冻结参数选取方面具有重要的参考价值和推广意义。     

关于进一步加强典型建设的思考

典型建设是政治思想工作的优良传统和重要内容,要适应新形势下典型建设中出现的一些新变化,就要进一步营造和优化先进典型的生长环境,坚持和强化先进典型的基本特性,发掘和发挥先进典型的积极作用,助推企业快速发展。     

Optimisation of specimen temperature and pulse fraction in atom probe microscopy experiments on a microalloyed steel

This paper details the effects of systematic changes to the experimental parameters for atom probe microscopy of microalloyed steels. We have used assessments of the signal-to-noise ratio (SNR), compositional measurements and field desorption images to establish the optimal instrumental parameters. These corresponded to probing at the lowest possible temperature (down to 20 K) with the highest possible pulse fraction (up to 30%). A steel containing a fine dispersion of solute atom clusters was used as an archetype to demonstrate the importance of running the atom probe at optimum conditions.     

实验课协同化管理系统

根据社会就业形势,各个学校都加强了对实验课程教学的力度,实验课越来越成为教学环节中的重要内容.如何使实验课教学更规范,更生动活泼,有效降低实验课的管理成本,提高实验课的教学效果,增加学生的学习热情,这些都是本课题研究的内容.