遥感影像建筑物阴影中树木阴影的去除方法

高分辨率多光谱遥感影像中的建筑物阴影具有重要作用。针对检测到的建筑物阴影经常受高大树木阴影影响的问题,在可分离亮度的Lab颜色空间建立树木颜色模型,使用查表法准确检测遥感影像中的树木区域。提出根据树木区域和光照方向去除建筑物阴影中树木阴影的方法,通过实验证明其有效性。     

可信计算发展研究

可信计算是目前信息安全技术研究的一个热点,它是在计算系统的基础上发展来的。从科学计算、容错计算到可信计算,介绍了可信计算的起源和发展,重点分析了可信计算属性、可信计算机系统和可信平台的体系结构等关键技术,并对目前可信计算的研究现状和可信软件系统存在的难点问题进行了总结。     

KKK算法研究及改进

研究一种为RFID标签和低运算能力设备建立动态密钥的算法——KKK算法,探讨算法的原理及发展现状。建立KKK算法仿真环境,在此基础上对各类KKK类算法进行比较。提出一种新的KKK类算法——KKK干扰算法,该算法与目前安全性较高的KKK-询问算法相比,性能效率更高。     

在不可靠网络环境下的时间戳服务方案

由于网络环境及各种外部条件导致有些网络的数据传输受到影响,网络时断时续,传输速度时快时慢,在这种情况下,的时间戳应用较为困难。就此情况提出了一种时间戳应用方案,通过引入了可信计算平台技术,利用可信计算平台模块中的滴答计数器与时间戳服务器相结合的方法,实现了在此种不可靠网络环境中的时间戳服务。     

Modeling of ice formation in porous solids with regard to the description of frost damage

The freezing and thawing of liquid in porous media in connection with the question concerning the frost durability of solid materials is an important subject for discussion in civil engineering. Each construction or body which is in contact with liquid and frozen water is criticized by its resistance to the environment. The durability concerning frost attacks of a building material is affected by its porosity and the pore size distribution. The ice formation is a phenomenon of coupled heat and mass transport in freezing porous media, and is primarily caused by the expansion of ice in connection with hydraulic pressure. The volume increases due to the freezing front inside the porous solid. Taking into account the aforementioned effects in porous materials, a simplified macroscopic model within the framework of the Theory of Porous Media (TPM) for the numerical simulation of initial and boundary value problems of freezing and thawing processes of super saturated porous solids will be presented. The phase change between the ice and the liquid phase is modeled by different real densities of the phases.     

Modeling of thermal mass transfer in porous media with applications to the organic phase transition in landfills

In order to describe the thermomechanical behavior of landfills, a constitutive model based on the macromechanical Theory of Porous Media (TPM) for a saturated thermoelastic porous body has been developed. The body under investigation consists of an organic and inorganic solid phase and a gas phase. All interaction relations between the constituents such as mass transfers, interaction forces and energy supplies are taken into consideration. Based on a consistent thermomechanical treatment the governing equations are obtained as a set of equations which consists of the balance equations of momentum and mass for each individual constituent, the balance equation of energy for the mixture and the physical constrained conditions. In this set of macroscopic equations, several parameters are contained. They are interrelated by constitutive relationships in order to complete the system of equations. This procedure renders the set of equations solvable. Thus, we obtain a mathematical concept to describe the motion of the solid phase, the pressure of the gas phase, the temperature of the mixture and the biodegradation of organic material into a gas mixture of methane and carbon dioxide produced by bacterial decomposition during stable methane fermentation (biogas).     

基于香气活力值的烤烟烟叶清(青)香风格特征分析

为探究不同烤烟烟叶(玉溪C3F和许昌C3F复烤烟叶)的清香风格特征,采用半制备型高效液相色谱(HPLC)和气相色谱-质谱联用(GC-MS)等技术分离鉴定了浓香型和清香型烟叶主流烟气中的香气成分,确定了11种清(青)香成分,通过建立GC-MS内标标准曲线测定了其在烟叶主流烟气中的释放量,计算了相应的香气活力值(OAV),比较了11种清香成分对烟气清香香韵的贡献度,并基于OAV对两种烟叶的清香风格特征进行了分析。结果表明:①2种烟叶主流烟气中11种清香成分的总释放量分别为5.16和4.47μg/支,其中3-乙酰基吡啶和香叶基丙酮的释放量较高;②2种烟叶主流烟气中2-乙基己醇的OAV均小于1,对烟气清香香韵的贡献较小,β-大马酮和二氢大马酮的OAV均较大,在彰显烟气清香香韵方面起主要作用;③除OAV小于1的2-乙基己醇外,其余10种清香成分在玉溪C3F烟叶主流烟气中的总OAV为8.91×106,是许昌C3F烟叶的5倍,这与玉溪C3F烟叶清甜香突出、清香明显的感官评价结果一致。     

卷烟主流烟气中一氧化碳的研究

CO是卷烟的有害成分之一。通过测定国内44种卷烟烟气成分,确定烟气中CO产生量与卷烟烟气中焦油、总粒相物(TPM)的关系;同时通过外加助燃剂考察了燃烧状态对烟气中CO的影响。气相色谱法测定卷烟烟气中的水分和非散射红外法测定卷烟烟气中的CO,实验数据采用回归分析。结果表明:高焦油、高TPM的卷烟烟气中CO含量也高;添加助燃剂有助于降低卷烟烟气中的CO,且对烟气TPM和焦油影响较小。     

部分国产卷烟主流烟气水分的分析研究

采用气相色谱法和非散射红外法分别对全国81种卷烟烟气中的水分、烟碱和CO进行了检测;芒森.沃克法测定烟丝中总糖;评吸法确定烟气水分大小对喉部感受的影响。同时,还考察了六种添加物对烟气水分的影响。结果表明:①烟气水分存在一定的规律性,水分大小与喉部舒适程度成正比;②烟气水分与TPM、CO和烟气烟碱呈一定的相关性,与烟丝的水分和总糖无明显的关联。烟气水分是多种因素共同作用的结果。     

浅议TPM在油田设备管理系统中的推行和运用

在了解TPM发展历程的基础上,认识到TPM在企业生产管理中发挥着重要作用,从而将TPM引进到油田企业设备管理中来,促进了油田企业设备管理的水平,提高了企业的经济效益。