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71.
ABSTRACT In this paper, we propose a method to regenerate Rational Polynomial Coefficients (RPCs) using KOMPSAT-3A imagery and to reduce the geolocation error using minimum ground control points (GCPs). To estimate the new RPCs, the physical sensor model fitted to KOMPSAT-3A imagery was utilized and virtual GCPs over the study area were created. The size of the virtual grid used was 20x20x20. To remove the sensor-related errors in physical sensor model, three different image correction models (image coordinate translation model, shift and drift model, and affine transformation model) were additionally applied. We evaluated our proposed method in two areas within Korea, one in urban (Seoul) and one in rural (Goheung) areas. The results showed that there was a significant improvement after applying the suggested approach in the two areas. The image coordinate translation model is suggested in terms of GCP requirement and expected errors estimated from the error propagation analysis using Gauss–Markov Model (GMM). 相似文献
72.
CT-1地震计传递函数测试仪的设计 总被引:6,自引:4,他引:2
将计算机控制技术应用到甚宽频带地震计的传递函数测试中。讨论了基本的测试方法和原理,阐述了传递函数测试系统的软、硬件设计,给出了测试系统的应用实例。该测试系统具有正弦波自动扫频、阶跃信号法和脉冲信号法等标定方法,满足了甚宽频带地震计的传递函数测试在观测频带、动态范围和测试精度等方面的要求。 相似文献
73.
74.
Application of the luciferase cell culture bioassay for the detection of refined petroleum products 总被引:1,自引:0,他引:1
A luciferase cell culture-based bioassay, developed to detect 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like activity of halo-genated and polycyclic aromatic hydrocarbons, was optimized to detect refined petroleum products and to determine their relative inducing potency. Quality control standards from 32 refined products (gasolines and diesels, jet fuels, lubricating oils, fuel oils and weathered products) and three commercial products were evaluated. Induction equivalents (I-EQs) were determined by direct comparison of the EC50 and EC20 values (based on the median and 20% TCDD maximal response, respectively) from dose-response curves for each product to those obtained with TCDD. Most petroleum products were active in the luciferase bioassay, with those products composed of fractions produced later in the distillation process (i.e. fuel oils) inducing higher levels. Additionally, weathering of products reduced their induction potency. Based on the high I-EQ estimates of many products, biological effects associated with exposure may have been previously underestimated using other diagnostic methods. 相似文献
75.
波动方程叠前深度偏移在地震勘探成像处理方面起着不可替代的作用。随着高性能大规模并行计算机技术的发展,波动方程叠前深度偏移计算在地震勘探中的应用有了很大进步。在波动方程叠前深度偏移处理中,庞大的数据规模与海量计算对计算性能提出了很高的要求。曙光4000A超级计算机系统是我国目前峰值速度最快的商用超级计算机系统,无论是硬件平台建设还是应用软件的配置方面,都具有良好的应用性能。基于该系统设计的三维波动方程叠前深度偏移(炮域)PSDM软件,采用动态负载平衡并行计算模式,具有较高的计算效率,高度的可扩展性和可靠性。 相似文献
76.
Neal Jackson Clive Tadhunter & William B. Sparks 《Monthly notices of the Royal Astronomical Society》1998,301(1):131-141
We present new Hubble Space Telescope ( HST ) continuum and spectral line images of the radio galaxy Cygnus A. The images show much complex structure in the central kpc2 . Continuum images show the central dust lane in detail, allowing detailed maps of E ( B − V ) to be constructed; the dust appears to follow a roughly Galactic extinction law. The emission-line components are resolved in the line images and investigated in detail. A clear 'opening cone' morphology is found, especially in the lines of Hα and [O i ]. Blue condensations are seen in the south-eastern emission component and surrounding the central region. These are almost certainly due to star formation, which began <1 Gyr ago as deduced from the colour of the regions. More extended blue continuum is also seen and corresponds to the blue polarized component detected by other recent spectropolarimetric observations. 相似文献
77.
腐泥煤变质系列热解色谱和氯仿沥青“A”的特点 总被引:2,自引:0,他引:2
对滕县、淄博两煤田与腐殖煤共生的不同煤级的腐泥煤进行了热解和氯仿沥青“A”的族组份分析,获得如下认识:热解的结果,Tmax、S1、S3、Ip全部高于共生腐殖煤,It全部低于共生腐殖煤,S2和Cp在低煤化阶段高于腐殖煤,而中,高煤化阶段则低于腐殖煤;氯仿沥青“A”都随煤级的增高而减少,腐泥煤全部高于腐殖煤,腐泥煤从低煤级到高煤级其族组份的排序从饱和烃>非烃>芳烃>沥青质变化到非烃>芳烃>沥青质>饱和烃;而腐殖煤族组份的排序则从沥青质>芳烃>非烃>饱和烃>沥青质。 相似文献
78.
M. C. Weisskopf M. Karovska G. G. Pavlov V. E. Zavlin T. Clarke 《Astrophysics and Space Science》2007,308(1-4):151-160
We present an overview of Chandra X-ray Observatory observations of neutron stars. The outstanding spatial and spectral resolution of this great observatory
have allowed for observations of unprecedented clarity and accuracy. Many of these observations have provided new insights
into neutron star physics. We present an admittedly biased and overly brief review of these observations, highlighting some
new discoveries made possible by the Observatory’s unique capabilities. This includes our analysis of recent multiwavelength
observations of the putative pulsar and its pulsar-wind nebula in the IC443 SNR.
相似文献
79.
1 STUDIEDREGIONANDANALYSISMETHODLocatedatnorthwesternmarginofTenggerDesertand70kmnortheastofMinqinCountyinGansuProvince,QingtuLakebelongstotheShiyangRiverDryDelta,andthealtitudeis1292-1310m.Theregionhasthecharacteroftemperatecontinentalariddesertcli… 相似文献
80.
应用修订的康拉德公式计算美国中东部温带地区日均温稳定≥10℃积温,并同我国相应纬度地区作了对比。这一对比揭示出我国东部温带并非世界同纬度地带夏半年热量资源最丰富。 相似文献