(1+1+1)维时空光孤子控制

本文通过数值地求解孤子控制系统下的（1＋1＋1）维非线性薛定谔方程,讨论在一定的孤子控制系统中传输的时空光孤子。结果表明,在一定的孤子控制系统中,（1＋1＋1）维时空光孤子可较稳定地传输。最后,讨论时空光孤子传输过程的稳定性。结果表明,在白噪声扰动下,时空光孤子传输过程是稳定的。     

HNCO hydrolysis performance in urea-water solution thermohydrolysis process with and without catalysts

The thermolysis of urea-water solution and its product, HNCO hydrolysis is investigated in a dual-reactor system. For the thermal decomposition below about 1073 K, the main products are ammonia (NH3) and isocyanic acid (HNCO) whereas at higher temperatures the oxidation processes take effect and the products include a low concentration of nitric oxide (NO) and nitrous oxide (N2O). The gas HNCO is quite stable and a high yield of HNCO is observed. The ratio of NH3 to HNCO increases from approximately 1.2 to 1.7 with the temperature. The chemical analysis shows that H radical is in favor of HNCO hydrolysis by instigating the reaction HNCO+H·→·NH2+CO and high temperature has positive effect on H radical. The hydrolysis of HNCO over an alumina catalyst made using a sol-gel process (designated as γ-Al2O3) is investigated. The conversion of HNCO is high even at the high space velocities (6×105 h-1) and low temperatures (393–673 K) in the tests with catalysts, which enhances HNCO hydrolysis and raises the ratio of NH3 to HNCO to approximately 100. The pure γ-Al2O3 shows a better catalytic performance than CuO/γ-Al2O3. The addition of CuO not only reduces the surface area but also decreases the Lewis acid sites which are recognized to have a positive effect on the catalytic activity. The apparent activation energy of the hydrolysis reaction amounts to about 25 kJ/mol in 393–473 K while 13 kJ/mol over 473 K. The overall hydrolysis reaction rate on catalysts is mainly determined by external and internal mass-transfer limitations.     

Numerical computations of the flow in a finite diverging channel

The flow in a finite diverging channel opening into a large space and resembling the experimental prototype of Putkaradze and Vorobieff （2006） was numerically investigated. The effects of the Reynolds number, initial condition, intersection angle, length of the wedge edges, and the outer boundary condition were examined. The numerical results showed that the flow in the wedge undergoes a change from symmetrical flow to unsymmetrical flow with a weak backflow, then a vortical （circulation） flow and finally an unsteady jet flow as the Reynolds number is increased for an intersection angle of 32° and a wedge edge of length 30 times the width of the inlet slit. For the unsteady flow, the jet attached to one side of the wedge constantly loses stability and rolls up into a mushroom-shaped vortex-pair near the outlet of the wedge. As the intersection angle is increased to 50°, a stable jet flow is observed as a new regime between the vortex and unsteady regimes. Both the intersection angle and the wedge length have negative effects on the stability of the flow, although the effect of the wedge length on the critical Reynolds number for the symmetry-breaking instability is not pronounced. The outer boundary condition was found not to affect the flow patterns inside the wedge significantly. At a certain Re regime above the onset of symmetry-breaking instability, the flows evolve into steady state very slowly except for the initial stage in the case of decreasing flow flux. Two different solutions can be observed within the normal observation time for the experiment, providing a possible explanation for the hysteresis phenomenon in the experiment.     

高校科研型开放实验室安全管理问题分析与对策

高校科研型开放实验室的安全管理问题是学校安全管理工作的一项重要内容.结合实验室管理工作实践,针对高校科研型开放实验室在安全管理中存在的问题,对相关管理制度实施的具体情况加以讨论,提出了实践中切实有效的几项管理措施.     

基于椭圆曲线的RFID标签访问安全机制研究

射频识别（Radio Frequency Identification,RFID）系统中读写器对标签的读写最为频繁,为了保证电子标签的安全,在开放信道内,读写信息不能以明文形式传输,需要采用高安全等级的密钥管理系统,弥补电子标签自身的安全设计不足,保证电子标签的安全运行。在分析各种加解密方案的基础上,提出了基于椭圆曲线的RFID标签访问安全适用的解决方案,为RFID信息安全做出探索性研究。     

湖湘传统生态价值观的内容与特征

源远流长的湖湘传统生态价值观在自然与人的关系问题上强调天地一体、万物平等,以天地和谐为目标。这种生态价值观在强调整体的同时,也认为天大地大人亦大,拥有万物皆为我所用的傲然气势。这样的湖湘生态价值观传统相对中国生态价值观传统而言,虽也难免局限,但却更具有一种主动和进取精神,必当可以为当下重塑人与自然的和谐关系提供宝贵的思想资源。     

人力资源管理中中层管理人员执行力的提高策略

在人力资源管理中,要想提高中层管理人员的执行力,首先要构建中层管理人员执行力的平台,另外要做好中层管理人员执行力的系统工程,重视中层管理人员的职业发展和职业规划,培养中层管理者的专业技能与团队合作意识。而在这个过程中,中层管理人员要把握好角色定位。     

浅谈企业眼中的中职校企合作

企业是校企合作的载体,本文从企业参与校企合作的原因着手,从企业的角度分析目前校企合作存在的问题,从学校的角度寻找对策,获取企业的认同,从而进一步推动校企合作的深层发展.     

基于FCM聚类及抖动半调的数码迷彩生成方法

数码迷彩因其不规则、不平滑的边缘特征而具备更强的伪装适应性．为快速有效地生成实用型数码迷彩,在传统迷彩基础上,提出一种基于误差扩散（E—D）抖动半调的数码迷彩生成算法．利用像素的三基色分量值作为特征值对迷彩原图作模糊C均值（FCM）聚类分析以提取迷彩主色,结合图像缩放、Gaussian滤波等图像处理,运用E—D抖动半调方法将传统迷彩图转换成数码迷彩图．实验证明,生成图既保持了迷彩原图的颜色分布及纹理特征,也具备了不规则的、锯齿状的边缘特征,有效地提高了迷彩的伪装隐蔽性能．     

试论英国在第一次柏林危机中的对苏冷战政策

1948年初,英国政府认为德国的分裂已经不可避免。与此同时,苏联为了警告西方国家分裂德国的行为,开始对西柏林采取封锁措施。为了保留西方国家在西柏林的地位,英国对苏联采取了强硬态度。1948年6月24日,苏联全面封锁西柏林,第一次柏林危机爆发,英国联合美国采取向柏林空运物资,以及让美国战略轰炸机进驻英国本土等措施与苏联对抗。同时,英国极力避免同苏联发生武装冲突,力图以"冷战"的方式与苏联对抗。