高光谱影像数据预处理技术评价     

孙婷张立朝  唐汉松 《测绘科学与工程》2007,27(1):59-62

高光谱影像数据预处理是构建高效的影像数据库以及实现地理目标成分信息反演与地理目标识别的基础。本文从反射率演算、光谱微分技术以及高光谱影像数据的降维处理等三个方面对高光谱影像数据预处理进行了研究。实现了基于高光谱影像的反射率反演算法，针对高光谱遥感数据影像分辨率比较低的现状，提出了直方图均衡化、色调平衡、对比度调整等影像处理算法，并给出了实验结果。  相似文献   

不同群体团头鲂生长性能分析     

朱春华 《广东海洋大学学报》1998,(1)

用随机区组试验方法,比较四种不同的选育群体团头鲂的后代和一个对照群体团头鲂的生长性能。结果表明：在同一环境条件下,远交群体比近交群体生长优势明显（|xi-xj|＞D0.01）;亲本年龄大（3足龄）的群体后代生长性能优于亲本年龄小（2足龄）的群体后代（|xi-xj|＞D0.05）;对照群体团头鲂与近交群体后代生长性能相当。  相似文献   

高压实膨润土热湿力性能测试   总被引：1，自引：0，他引：1  

沈珍瑶  李书绅 《水文地质工程地质》1998,25(2):8-9

本文介绍了高压实样品的制样特点,测试了高压实膨润土样的导热系数,热膨胀系数,对高压实膨润土热湿力特性研究有较大参考价值。  相似文献   

矩形钢筋混凝土水处理池震害预测方法及抗震对策   总被引：2，自引：0，他引：2  

郭恩栋  冯启民  高惠瑛  翟桐  廖旭 《地震工程与工程振动》1998,18(2):33-37

提出了矩形钢筋混凝土水处理池的一种震害预测方法,并对海口市米铺水厂中的水处理池进行了计算分析,论述了水处理池的对抗对策。  相似文献   

强夯地基效应及加固机制浅析   总被引：6，自引：0，他引：6  

卢小兵  张倬元 《地质灾害与环境保护》1998,9(4):11-15,20

强夯地基效应,是指经强夯处理使地基土的结构形式,强度和变形大小,及其作用过程发生的改变。通过对强夯过程中一系列的现象分析,揭示强夯地基效应的形成机制,对强夯地基效应的三个方面及其之间的联系进行分析,其结论对于强夯处理设计和加固机制的认识有较大意义。  相似文献   

超临界萃取技术在生物资源开发和有机废水处理中的应用研究   总被引：1，自引：0，他引：1  

刘华 《矿物岩石地球化学通报》1998,(1)

超临界萃取技术在生物资源开发和有机废水处理中的应用研究＠刘华￥中国科学院地球化学研究所超临界ＣＯ＿２萃取,有机废水处理,珊瑚姜油,辣椒色素超临界萃取技术在生物资源开发和有机废水处理中的应用研究刘华（中国科学院地球化学研究所,贵阳５５０００２）收稿日期：１９...  相似文献   

球形赖氨酸芽孢杆菌(Lysinibacillus sphaericus)对斑马鱼幼鱼生长、肠道菌群及代谢的影响          下载免费PDF全文

王涵颖  张心月  彭怀云  杨君烨  邱浩宇  黄玲  陶晨智  王萍 《海洋与湖沼》2024,55(1):265-278

旨在探究养殖水体中添加球形赖氨酸芽孢杆菌对斑马鱼幼鱼生长、抗氧化免疫、肠道菌群与代谢的影响。将初体重为(0.019±0.003) g的270尾斑马鱼随机均分为3组, ZF0组(对照组, 基础饲料)、ZF5组(基础饲料+10⁵CFU/mL球形赖氨酸芽孢杆菌)与ZF7组(基础饲料+10⁷CFU/mL球形赖氨酸芽孢杆菌), 每组3个平行,试验周期为33 d。实验结果表明: (1) 各组间的终末体重、增重率和特定生长率都没有显著性差异(P>0.05)。(2) ZF5和ZF7组的GPT活性显著高于ZF0组(P<0.05), ZF5组AKP的活性显著高于其他组(P<0.05)。(3) ZF7组胰蛋白酶和脂肪酶的活性相对于ZF0和ZF5组显著提高(P<0.05)。(4) ZF7组肠道绒毛高度、V/C都显著高于ZF0与ZF5组(P<0.05); ZF7组的隐窝深度显著低于其他两组(P<0.05)。(5) 从肠道菌群组成来看, 各组间优势菌门均为变形菌门(Proteobacteria), ZF5和ZF7组显著降低了肠道中梭杆菌门(Fusobacteriota)的丰度并显著提高了放线菌门(Actinobacteriota)的丰度(P<0.05)。属水平上, 对照组与试验组的优势菌属为鲸杆菌属(Cetobacterium), 试验组显著减少了邻单胞菌属(Plesiomonas)的丰度同时显著提高了戈登氏菌属(Gordonia)、细杆菌属(Microbacterium)等有益菌属的丰度(P<0.05)。(6)ZF5和ZF7组与ZF0组的肠道代谢物差异明显, 其中Lipoxin a4、Prostaglandin g2和11-dehydrothromboxane b2显著上调(P<0.05), 5''-phosphoribosyl- 5-amino-4-imidazolecarboxamide (aicar)显著下调(P<0.05)。差异代谢物主要富集在ABC转运蛋白、神经活性配体-受体相互作用以及丙氨酸、天冬氨酸和谷氨酸通路中。综上所述,养殖水体中添加球形赖氨酸芽孢杆菌有利于改善斑马鱼幼鱼的肠道消化性能、组织结构和微生物多样性及其代谢产物。  相似文献   

Experimental study and constitutive modelling of elasto‐plastic damage in heat‐treated mortar     

Xiao‐Ting Chen  J. F. Shao  C. A. Davy  F. Skoczylas 《国际地质力学数值与分析法杂志》2010,34(4):357-382

This study investigates the effect of a heat‐treatment upon the thermo‐mechanical behaviour of a model cement‐based material, i.e. a normalized mortar, with a (w/c) ratio of 0.5. First, a whole set of varied experimental results is provided, in order to either identify or validate a thermo‐mechanical constitutive model, presented in the second paper part. Experimental responses of both hydraulic and mechanical behaviour are given after different heating/cooling cycling levels (105, 200, 300, 400^°C). The reference state, used for comparison purposes, is taken after mass stabilization at 60^°C. Typical uniaxial compression tests are provided, and original triaxial deviatoric compressive test responses are also given. Hydraulic behaviour is identified simultaneously to triaxial deviatoric compressive loading through gas permeability K_gas assessment. K_gas is well correlated with volumetric strain evolution: gas permeability increases hugely when ε_v testifies of a dilatant material behaviour, instead of contractile from the test start. Finally, the thermo‐mechanical model, based on a thermodynamics approach, is identified using the experimental results on uniaxial and triaxial deviatoric compression. It is also positively validated at residual state for triaxial deviatoric compression, but also by using a different stress path in lateral extension, which is at the origin of noticeable plasticity. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

C++虚拟继承状态下对象复制语义的分析研究     

楚丁  彭宗锦 《成都信息工程学院学报》2007,22(5):593-597

分析C 虚拟继承状态下的对象复制语义学.通过分析当前主流C 编译器对这个语义的支持情况,比较了它们之间实现上的差异;最后提出一种基于软件编码的实现方案,并比较了各种方案的性能优劣,以求更大限度的发挥C 的性能.  相似文献   

Experimental Study on Response Performance of VIV of A Flexible Riser with Helical Strakes   总被引：1，自引：1，他引：0  

高云  付世晓  曹静  陈一帆 《海洋工程》2015,29(5):673-690

Laboratory tests were conducted on a flexible riser with and without helical strakes. The aim of the present work is to further understand the response performance of the vortex induced vibration (VIV) for a riser with helical strakes. The experiment was accomplished in the towing tank and the relative current was simulated by towing a flexible riser in one direction. Based on the modal analysis method, the displacement responses can be obtained by the measured strain. The strakes with different heights are analyzed here, and the response parameters like strain response and displacement response are studied. The experimental results show that the in-line (IL) response is as important as the cross-flow (CF) response, however, many industrial analysis methods usually ignore the IL response due to VIV. The results also indicate that the response characteristics of a bare riser can be quite distinct from that of a riser with helical strakes, and the response performance depends on the geometry on the helical strakes closely. The fatigue damage is further discussed and the results show that the fatigue damage in the CF direction is of the same order as that in the IL direction for the bare riser. However, for the riser with helical strakes, the fatigue damage in the CF direction is much smaller than that in the IL direction.  相似文献