基于激光雷达数据SVM分类的室内环境识别研究

语义地图构建对移动机器人导航与规划具有重要意义，而环境分类是语义地图构建的核心问题。目前所采用的环境分类方法匹配率较低，已成为语义地图构建所面临的主要问题。对此笔者提出了一种基于支持向量机的分类方法，该方法利用激光雷达数据提取环境几何特征，训练SVM分类器对机器人工作空间模式进行识别，并将所提算法用于室内环境的语义分类。实验结果表明，该分类方法具有较高的识别率，可有效地实现语义地图构建。     

开源教学平台的可用性研究——以Sakai为例

越来越多的国内外高校开始考虑使用基于开源软件的网络教学平台,在投入使用之前,开源教学平台一般需要进行二次开发过程,其中需要重点解决平台的可用性问题,因为网络教学平台的可用性是影响学习效果的重要因素.发现并解决网络教学环境中的可用性问题,是促进人机交互、提高学习效率的重要途径.开源教学平台的可用性指的是系统的有效性、效率和满意度,分析了网络教学平台的可用性诉求,并以浙江大学Sakai开放学习平台为例,进行个案研究.使用了ThinkAloud、观察法和访谈法等可用性测试方法,研究结果发现,浙江大学Sakai开放学习平台主要功能人机交互设计合理,但是由于文化差异和用户使用习惯问题,部分功能存在一定的可用性问题,值得学习平台设计者借鉴.     

微机Windows 9X平台上的分子模拟技术

通过例子介绍了微机Windows平台上的分子模拟技术——分子结构的生成、分子力学量子化学计算及计算结果的图形显示等内容。     

手机广告链中移动运营商的努力动机研究与仿真

建立了由单手机广告主、手机广告代理商和移动运营商构成的三级广告产业链之间的基于协作的收益共享契约模型,分析了在以移动运营商为主导的手机广告链中,移动运营商的努力动机受收益共享和努力成本补偿参数的影响.采用量化分析和模拟仿真结合的方法,得出契约参数只有在满足一定条件下,移动运营商所做出的最优努力水平投入决策,将使得整个手机产业链收益最大化,实现多方共赢.     

Application of nanodiamonds in human body fluid analysis by matrix-assisted laser desorption/ionization mass spectrometry

Direct mass spectrometric analysis of complex biological samples is very important and challenging. In this paper, nanodiamonds have been successfully used in matrix-assisted laser desorption/ionization mass spectrometric analysis of human serum and urine. As a practical tool and platform, it can be widely used in the field of humoral proteomics, and it plays a very promising role in clinical diagnosis, including identification of novel disease-associated biomarkers.     

化学化工虚拟仿真实验教学平台的建设与应用

Virtual simulation teaching is a new type of teaching mode in recent years, which is a fusion of multiple disciplines, multiple regions and multi-level laboratory teaching methods. Taking virtual simulation experiment platform construction of chemical engineering in Tianjin University as an example, this paper introduces the chemical safety knowledge, the integration of theoretical knowledge, the experimental content, the specific content of virtual simulation resources, and the characteristic of virtual simulation experiment platform. This platform provides a new model of efficient combination of virtual simulation resources and traditional teaching resources, which promotes the development of chemical laboratory teaching.     

Spectrum planning and performance evaluation between heterogeneous satellite networks

A new network has been recently proposed for the provision of fixed broadband services via high altitude platform stations (HAPS) in the 48/47 GHz band. One of the critical issues of this technology is spectrum sharing with the fixed satellite service. This paper examines the effect of Earth-to-stratosphere co-channel interference produced by ground stations of HAPS network to geostationary orbit (GEO) satellite receivers and proposes an interference-to-noise (I/N) calculation model for the evaluation of the current HAPS ground stations power characteristics set by ITU-R. Analytical and simulation results for archetypal systems in realistic scenarios indicate that efficient use of the spectrum shared between heterogeneous HAPS and Fixed Satellite Networks is feasible. Certain consideration is needed prior to the HAPS network development in suburban areas for latitudes from 55° to 65°, and in rural areas for latitudes from 60° to 75°.     

Use of a displacement model for solvent sorption to study non-specific selectivity in reversed-phase liquid chromatography

Summary A thermodynamic equation is derived for the non-specific selectivity of alkyl bonded phases as a function of the mobile phase composition using a displacement mechanism to model the sorption of solvents into the bonded phase. The equation is used to calculate the thermodynamic parameters which characterize the incremental behavior of a hydrophobic group in ethyl alkanoate and methyl perfluoroalkanoate ester solutes chromatographed with water-methanol and water-acetonitrile mobile phases on both octyl and octadecyl bonded phases.     

铁氰化钴修饰石墨烯平面电极对过氧化氢的传感作用

利用高分子支撑法将气相沉积(CVD)石墨烯从铜基底上转移到聚对苯二甲酸乙二醇酯(PET)基底上,制备出石墨烯平面电极(GPE), 通过循环伏安法将铁氰化钴(CoHCF)纳米颗沉积到GPE上,得到铁氰化钴修饰石墨烯平面电极(CoHCF/GPE).研究表明,此电极对过氧化氢具有良好的传感作用,从而构建一种新型无酶过氧化氢传感器.此传感器在过氧化氢浓度为5.0-1200 μmol/L范围内,响应电流与浓度呈现良好的线性关系,检出限为7.1 nmol/L (S/N=3),响应时间约为2 s,具有稳定性好、抗干扰能力强、制备简单等优点.