基于ICA/MNF变换的高分影像滑坡灾害检测方法研究

快速准确地从灾后影像中提取出受灾区域对于灾后救援具有重要意义。鉴于现有提取方法过度依赖滑坡在影像中的光学、纹理等特征的问题,研究了一种结合独立成分分析(ICA)与最小噪声比率变换(MNF)的变化检测方法,以单一时相的影像为基础,运用基于负熵最大化的Fast-ICA算法分离出两个时相影像相互正交的独立成分,并构建对应独立成分的差异影像,最后用最小噪声比率变换实现分布于各个差异影像上变化信息的集中,应用直方图阈值法得到了最终的滑坡灾害信息。选取了滑坡灾害前后两时相的高分辨率遥感影像数据进行实验,结果证实了方法的可行性。     

基于振型小波变换的铁路桥墩损伤识别研究

利用模态振型和小波变换对铁路桥墩损伤识别进行了研究,并通过数值模拟对该方法进行了验证。研究结果表明:利用低阶模态振型的小波变换能够对铁路桥墩的损伤进行定位,适当尺度上的低阶模态振型及模态振型差的小波变换对单一位置及多位置损伤识别均较有效,且可对损伤程度进行估计。     

江苏茅山断裂带中段重力异常多尺度分析及其构造识别

采用小波变换多尺度分析,将茅山断裂带中段的重力数据分解为不同尺度的重力异常,用于研究该区的地质构造特征。小波变换多尺度分析可以将重力数据分解为不同深度的局部异常和区域异常,局部异常解释为浅部地质体引起,区域异常解释为深部地质体引起。基于此种地质解释,分析了不同深度地质体与重力异常的对应关系,并对产生异常的原因进行解释,推断出该区的主要断裂构造,并对已有研究成果进行修正。研究结果表明,断裂带中段的构造形式与重力异常之间有较好的对应关系。     

相变式烟气换热器对湿法脱硫系统水耗量的影响

复合式相变换热技术是一项解决低温腐蚀难题的全新换热技术,通过此项技术可以深度利用锅炉烟气余热,降低了锅炉出口的烟气温度。通过采用该技术可以降低进入湿法脱硫系统内的烟气的温度,明显的减少了脱硫系统的工艺水耗量,本文主要探讨了锅炉增加复合式相变换热器后对湿法脱硫系统工艺水耗量的影响。     

Removal of arsenate with hydrous ferric oxide coprecipitation：Effect of humic acid

Insights from the adverse effect of humic acid(HA) on arsenate removal with hydrous ferric oxide(HFO) coprecipitation can further our understanding of the fate of As(V) in water treatment process. The motivation of our study is to explore the competitive adsorption mechanisms of humic acid and As(V) on HFO on the molecular scale. Multiple complementary techniques were used including macroscopic adsorption experiments, surface enhanced Raman scattering(SERS), extended X-ray absorption fine structure(EXAFS) spectroscopy, flow-cell attenuated total reflectance Fourier transform infrared(ATR-FTIR) measurement, and charge distribution multisite complexation(CDMUSIC) modeling. The As(V) removal efficiency was reduced from over 95% to about 10% with the increasing HA concentration to 25 times of As(V) mass concentration. The SERS analysis excluded the HA-As(V) complex formation. The EXAFS results indicate that As(V) formed bidentate binuclear surface complexes in the presence of HA as evidenced by an As-Fe distance of 3.26–3.31 ?. The in situ ATR-FTIR measurements show that As(V) replaces surface hydroxyl groups and forms innersphere complex. High concentrations of HA may physically block the surface sites and inhibit the As(V) access. The adsorption of As(V) and HA decreased the point of zero charge of HFO from 7.8 to 5.8 and 6.3, respectively. The CD-MUSIC model described the zeta potential curves and adsorption edges of As(V) and HA reasonably well.     

Graphene-supported nanoscale zero-valent iron：Removal of phosphorus from aqueous solution and mechanistic study

Excess phosphorus from non-point pollution sources is one of the key factors causing eutrophication in many lakes in China,so finding a cost-effective method to remove phosphorus from non-point pollution sources is very important for the health of the aqueous environment. Graphene was selected to support nanoscale zero-valent iron(nZVI)for phosphorus removal from synthetic rainwater runoff in this article. Compared with nZVI supported on other porous materials,graphene-supported nZVI(G-nZVI) could remove phosphorus more efficiently. The amount of nZVI in G-nZVI was an important factor in the removal of phosphorus by G-nZVI,and G-nZVI with 20 wt.% nZVI(20% G-nZVI)could remove phosphorus most efficiently. The nZVI was very stable and could disperse very well on graphene,as characterized by transmission electron microscopy(TEM) and scanning electron microscopy(SEM). X-ray photoelectron spectroscopy(XPS),Fourier Transform infrared spectroscopy(FT-IR) and Raman spectroscopy were used to elucidate the reaction process,and the results indicated that Fe-O-P was formed after phosphorus was adsorbed by G-nZVI. The results obtained from X-ray diffraction(XRD) indicated that the reaction product between nZVI supported on graphene and phosphorus was Fe3(PO4)2·8H2O(Vivianite). It was confirmed that the specific reaction mechanism for the removal of phosphorus with nZVI or G-nZVI was mainly due to chemical reaction between nZVI and phosphorus.     

鱼粉行业恶臭污染物产生与成分分析探讨

针对目前鱼粉行业废气污染严重、排放量大、成分复杂的特性和测定难度较大、监测准确度较低等实际情况，采用实际监测数据，利用傅立叶红外光谱分析仪，有针对性地对鱼粉生产过程中及采取治理措施后恶臭污染物的排放进行了现场连续监测，得到了全面的监测数据。     

基于特征融合的区域生态环境动态监测研究

以1993、2000、2006和2013年4期遥感影像为主体数据源,选取山西省翼城县为实验区,利用遥感和GIS的技术手段对研究区生态环境进行动态监测和评价。为了更好地体现和突出图像中的纹理特征,满足矿区土地利用和生态环境状况调查解译精度的要求,在HIS小波融合的基础上,通过选取每个像元的特征向量并对其进行主成分分析,将获得的主成分作为高频系数融合规则权重来对原图像进行融合处理,并在此基础上将结果应用于生态环境要素提取和生态环境状况评价中。结果表明:该方法的标准差与信息熵最大,均值适中,在抑制光谱信息扭曲和提高图像清晰度等评价参数上优于其他方法;与1993年相比较,2013年高植被覆盖度区域减少了9 240.87 hm2,中度植被覆盖区域增加了14 036.44 hm2,中度、强度和极强土壤侵蚀面积分别增加了2 955.2、4 850.9和278.43 hm2;实验区生态环境质量指数由37.5上升到40.7,2013年又下降到了33.1,表明了20年间生态环境质量呈现出先改善后恶化的局面。     

基于小波变换的行波故障测距系统

高压输电线路故障的准确定位,能够缩短故障修复时间,提高供电可靠性,减少停电损失.对于占绝对多数的瞬时性故障来讲,准确定位,可以找出故障的原因,及时发现隐患,防止事故再次发生.基于小波变换的行波故障测距系统将小波变换引入双端行波故障定位,实现了快速可靠的定位和选相.     

成都市春季大气飘尘目标变换因子分析

对成都市大气飘尘（ＳＭＰ〈１０μｍ）用目标变换因子分析（ＴＴＦＡ）作源解析。结果表明，主要排放源及其贡献为，道路交通尘（１６．８％），冶金尘（１９．２％），垃圾与草木焚烧烟尘（２４．８％），燃煤飞灰（５４．３％），大气尘污染以煤烟为主。