改进灰色模型在中长期电力负荷预测中的应用

针对中长期电力系统负荷预测,在前人已有成果的基础之上,对普通灰色模型进行了改进.一方面对历史数据进行二次平滑处理,大大消除了干扰因素;另一方面利用带有马尔可夫链符号估计的残差修正技术对未来残差的符号进行预测以修正灰色模型的预测结果.以某地区多年以来的历史数据为基础,建立了数学模型,通过实际数据计算表明:改进后的灰色负荷预测方法可以应用于电力系统中长期负荷预测,而且较普通灰色预测模型在预测精度上有着明显的提高,尤其是对于较远时间的负荷预测有着较为理想的预测精度,表明了该种方法的有效性和实用性.     

8407模具钢表面渗铝的研究

为了防止模具表面产生热疲劳裂纹,通过冷喷涂在8407钢试样表面形成了一层铝涂层,再进行扩散处理,在试样表面形成了渗层.通过理论分析确定低温渗铝的工艺参数,并与渗铝实验进行检验,重点研究了扩散温度和扩散时间对渗层质量的影响.结果表明,8407钢经过冷喷涂铝后再进行扩散处理能够实现低温渗铝.在550℃下扩散4 h左右形成的渗层质量比较理想.     

Effective prediction of DEA model by neural network

In this paper,a fast neural network model for the forecasting of effective points by DEA model is proposed,which is based on the SPDS training algorithm.The SPDS training algorithm overcomes the drawbacks of slow convergent speed and partially minimum result for BP algorithm.Its training speed is much faster and its forecasting precision is much better than those of BP algorithm.By numeric examples,it is showed that adopting the neural network model in the forecasting of effective points by DEA model is valid.     

Prevention of rockburst by guide holes based on numerical simulations

We studied variations in the stress field around guide holes drilled during tunnel excavation to understand the mechanical mechanism by which these holes help prevent rockburst. The study used elasto-plastic analysis of a circular chamber under non-axisymmetrical loads. The results showed that the unloading of in-situ stresses, and the forming of a secondary stress field, leads to a severe change in the stress field around the guide holes. This causes the formation of an X-shaped area of plastic deformation, which prevents the rockburst. Adopting a sub-model finite dement technique, we analyzed the factors that influence the distribution of the plastic area, such as the guide hole distribution and the in-situ stress state. The calculations showed that higher initial stresses result in greater adjustment to the stress field. When the stress concentration is greater the size of the plastic area surrounding the guide hole is larger. A multi-row distribution of the guide holes shaped like a quincunX can increase the interconnectivity of the plastic areas and allow the plastic area to extend from the tunnel wall deep into the surrounding rock. An optimized design was put forward based on the distribution of the plastic area around guide holes and the factors that influence it.     

Relation between structural evolution of the Longmenshan orogenic zone and sedimentation of its foreland basin

In order to determine the area for oil and gas exploration in China's north Sichuan basin, we have divided the time during which the Longmenshan foreland basin was formed into five periods, based on the sedimentary response relationship of the fore-land basin to structural evolution: 1) a late Triassic Noric period; 2) an early-Middle Jurassic period; 3) a late Jurassic to early Cre-taceous period; 4) a late Cretaceous to Paleogene-Neogene period and 5) the Quaternary period. As well, we analyzed the sedimen-tary environment and lithologic features of every basin-forming period. The results show that there are several favorable source-reservoir-cap assemblages in our study area, making it a major region for future oil and gas exploration in China's northern Sichuan basin.     

周期阵列压痕奇异应力场与开裂（PartⅡ：压痕开裂临界载荷）

周期阵列压痕方法是研究微观摩擦学的工具之一。由于周期阵列刚性压头压在半平面弹性体的表面时,会产生周期的Ⅰ型奇异压应力场,该奇异应力场的应力集中达到一定程度时,即达到临界条件时,该奇异应力场所在的边界将开裂。压痕边界的开裂问题是一个新型的断裂力学问题,通过边界移动的能量释放率的分析给出了压痕边界开裂能量释放率数学表征,并给出边界开裂的临界载荷和临界开裂角。     

复合掺杂Nd（III）和Zn（II）非晶态Ni（OH）2电极活性材料的制备及其表征

以NiSO4、ZnSO4和Nd（NO3）3为原料,采用共沉淀快速冷冻法制备出了复合掺杂稀土Nd（III）和Zn（II）的非晶态氢氧化镍粉体材料。测试发现：样品材料微结构无序性强,结晶水含量较高。将样品材料制备成镍电极并组装成MH—Ni电池,在80mA／g恒电流充电5．5h、40mA／g恒电流放电、终止电压为1．0V的充放电制度下,复合掺杂6％Nd（III）和6％Zn（II）样品材料电池的放电平台为1．2624V,放电比容量为343．12mAh／g,远高于目前应用的B-Ni（OH）2电极活性材料的放电比容量。     

基于图像的静脉输液无液检测的新方法

针对国内外为实现静脉输液无液自动检测而采用的各种传感器技术存在的各种问题,提出基于图像的静脉输液无液检测的新方法.通过CCD摄像机采集输液器液位图像,数字化后输入计算机,由计算机软件进行图像处理和分析,得到输液器是否无液的信息.该方法的研究,实现了将数字图像处理技术融合到静脉输液无液检测应用中,丰富了图像处理内容的同时为静脉输液无液检测提供了新思路.