?radiometric

radiometric發(fā)音

[?re?d????metr?k]

英：　　美：

radiometric中文意思翻譯

adj. 輻射測量的；輻射度的

radiometric常見(jiàn)例句

1 、radiometric assay of microorganism───微生物的放射分析(法), 微生物放射測定法

2 、A Study on Relative Radiometric Correction of Multitemporal Remote Sensing Images───多時(shí)相遙感圖像相對輻射校正

3 、radiometric sampling───放射取樣法

4 、Because of these advantages, sedimentary evidence can be dated with sufficient accuracy by radiometric methods to establish a precise chronology of the ice ages.───因為這些優(yōu)點(diǎn)，沉積物證據可通過(guò)輻射測量的方法提供足夠精確性來(lái)建立精細的冰河世紀年代表。

5 、Measurement chain of influence quantities and uncertainty of radiometric calibration for imaging spectrometer[J].───引用該論文 李幼平,禹秉熙,王玉鵬,方偉.

6 、radiometric polarography───放射極譜法

7 、Using radiometric dating methods, Sugden determined that the ash settled into the fissure after a volcanic eruption 8.1 million years ago.───使用放射性斷代法，蘇格丹發(fā)現火山灰早在810萬(wàn)年前的一次火山噴發(fā)后，就已進(jìn)入了裂縫。

8 、radiometric sextant───無(wú)線(xiàn)電六分儀

9 、Simulation of microwave radiometric images on complex scene[J].───引用該論文 黃全亮,張祖蔭,郭偉.

10 、radiometric measure───放射性測量

11 、Estimation of Heihe Basin Net Primary Productivity Using the CASA and Multi-spectral Radiometric Data───基于CASA和多光譜遙感數據的黑河流域NPP研究

12 、Keywords Radiometric method;oil and gas radioactive anomaly;anomalous pattern;───放射性方法;油氣放射性異常;異常模式;

13 、The calibration of radiometric sensors is critical to ensure the accuracy of the remote sensing data and their usability.───光輻射傳感器的定標是保證遙感數據精度及可利用價(jià)值的基礎支撐技術(shù)。

14 、Level 1G data product of DMC remote sensing mini-satellite has been processed by band registering, radiometric correction and systematically geometric correction.───DMC遙感小衛星1G級數據產(chǎn)品雖然經(jīng)過(guò)了波段配準、輻射校正和系統幾何校正處理,但尚不能作為海嘯災害解譯和評估的基礎圖像。

15 、Based on radiometric and geometrical correction of ASTER imagery data, the land-use classification of coastal area in the east of Shenzhen were investigated in this study.───摘要以深圳市東部濱海地區為試驗區，對2004年11月21日ASTER遙感數據進(jìn)行輻射和幾何精校正處理，實(shí)地建立分類(lèi)樣地；

16 、Radiometric Calibration of FY-2C Meteorological Satellite and Its Result Analysis───FY-2C星輻射定標及其結果分析

17 、Spectral radiometric calibration───光譜輻射定標

18 、An effective radiometric calibration method which is useful for the FourierTransform Imaging Spectrometer data with low SNR is proposed. 5.───4、針對低信噪比干涉數據，提出一種行之有效的干涉光譜輻射定標方法；

19 、radiometric cross-calibration───交叉定標

20 、Diagnosis and Application of Compton Backscattering Technique in Storage Ring for Electron Beam I Accurate Measurement of the Electron Beam Energy and Experimental Stations of Radiometric Standard───康普頓背散射技術(shù)對貯存環(huán)電子束診斷及其應用 I電子束能量的精確測量及光學(xué)標準實(shí)驗站

21 、radiometric gauge───放射性計器

22 、radiometric age dating───地質(zhì)年代的放射性測定

23 、HIGHLY ACCURATE RADIOMETRIC CALIBRATION FOR ERB-NS TOTAL WAVELENGTH CHANNEL WITH A WIDE FIELD-OF-VIEW───大視場(chǎng)ERB-NS全波探測通道的高精度輻射定標

24 、Synchrotron radiation be used for spectral radiometric standards───同步輻射光源用于光譜輻射標準

25 、Keywords Imaging spectroscopy;Data processing;Data compression;Radiometric calibration;Spectral unmixing;Target detection;───光譜成像技術(shù);數據處理;數據壓縮;輻射定標;光譜解混合;目標探測;

26 、Of a radiation. Description of the spectral character of a radiation by the relative spectral distribution of some radiometric quantity (radiant flux (power), radiant intensity, etc.).───對輻射而言。用某一輻射度量（輻射功率，輻射強度等）的相對光譜分布對一輻射的光譜特性進(jìn)行的描述。

27 、Radiometric Geophysics───放射性物探

28 、Radiometric correction is a very important preprocess in the dynamic monitoring of landuse.It can improve the precision of landuse classification and the change detection.───在土地利用變化動(dòng)態(tài)監測中,輻射校正是非常重要的一項預處理過(guò)程,它能夠提高土地利用分類(lèi)及土地利用變化檢測的精度。

29 、radiometric sorter───放射性分選機

30 、Radiometric Cross-calibration of the FY1D/VIRR and EOS/MODIS in the Visible and Near-infrared Spectral Bands───利用EOS/MODIS交叉定標FY1D/VIRR可見(jiàn)光-近紅外通道

31 、radiometric curve───放射能曲線(xiàn)

32 、radiometric titration───放射滴定

33 、STUDY ON GRAND-BASED MILLIMETER WAVE RADIOMETRIC IMAGE SIMULATION───地基毫米波輻射圖像模擬生成方法的研究

34 、Ground Simultaneous Measurements and Analysis of Radiometric Characterization of Dunhuang Test Site for Calibrating CBERS-1 Sensors───CBERS-1CCD相機飛行絕對輻射標定試驗地面同步測量與場(chǎng)地輻射特性分析

35 、In the image fuse step, a radiometric and color compensation stage allows the development of an automatic and seamless mosaicing system.───在圖像融合方面，有效消除了顏色和光照差異，最終實(shí)現自動(dòng)的無(wú)縫拼接系統。

36 、radiometric respirometer───放射測量用呼吸測定器

37 、Relative radiometric normalization of remotely sensed images based on improved automatic scattergram-controlled regression───基于改進(jìn)的自動(dòng)散點(diǎn)控制回歸算法的遙感影像相對輻射歸一化

38 、Radiometric techniques are not always appropriate to search for uranium deposits.───放射性方法在鈾礦普查中并不總是有效的。

39 、Research on a Radiometric Calibration Device for a Large Aperture Infrared Opto-electric System on Spot───大口徑紅外光電系統現場(chǎng)輻射定標裝置的研制

40 、A MMW Radiometric Image Partition Method Based on Low Brightness Temperature Target───一種基于低亮溫目標的毫米波輻射圖像分割方法

41 、radiometric instruments───微輻射探測儀

42 、A STUDY OF THE DIFFERENCE BETWEEN TRUE SURFACE TEMPERATURE AND RADIOMETRIC SURFACE TEMPERATURE───地表溫度和地表輻射溫度差值分析

43 、Utility of Assimilating Surface Radiometric Temperature Observations for Evaporative Fraction and Heat Transfer Coefficient Retrieval───同化地面輻射儀的溫度觀(guān)測對蒸發(fā)部分和熱傳輸系數反演效用

44 、Subsequent discoveries were made by geological mapping and low-level airborne radiometric surveys───地質(zhì)填圖和低空放射性航測又繼續探明了一批礦點(diǎn)。

45 、radiometric age───放射測年代

46 、Clutter Rejection Method in SAR Radiometric Calibration───SAR輻射定標中的地物雜波抑制方法

47 、A method of optical radiometric calibration based on correlated photons was proposed to improve calibration precision.It was independent of the methods based on radiometric source or detectors.───為提高定標精度, 提出一種基于相關(guān)光子的光輻射定標方法, 它是一種獨立于基于輻射源和基于探測器的定標方法。

48 、radiometric exploration───放射性勘探

49 、Analysis on the influence factors of microwave radiometric imaging quality[J].───引用該論文 桂良啟,張祖蔭,郭偉.

50 、atmospheric and radiometric correction───大氣輻射校正

51 、Keywords Low sulphidation epithermal Au deposit;hydrothermal alteration;high resolution aeromagnetic survey;Airborne radiometric sensor;Gravity anomaly;───低硫化物淺成熱液金礦床;熱液蝕變;高分辨率航空磁測;航空放射性測量;重力異常;

52 、rapid radiometric───快速輻射測量的

53 、Radiometric characterization of field radiometers in support of the 1997 Lunar Lake, Nevada, experiment to determine surface reflectance and top-of-atmosphere radiance───1997年內華達月亮湖確定表面輻射和大氣頂輻射試驗所用的場(chǎng)輻射計的輻射特征

54 、The rocks that held the fossils didn't have the right minerals for radiometric dating.───包住這些化石的巖石中沒(méi)有確定放射測量日期所要求的那些礦物質(zhì)。

55 、The three chemical mutagens were mitomycin C(MMC,DNA crosslinker),bleomycin(BLM,radiometric agent),methyl methanesulfonate(MMS,alkylating agent).───3種化學(xué)誘變劑是絲裂霉素C(MMC ,DNA交聯(lián)劑 )、博來(lái)霉素 (BLM ,似X線(xiàn)劑 )、甲基甲烷磺酸酯 (MMS ,烷化劑 )。

56 、Secondly, the relation between high resolution spaceborne SAR radiometric calibration and SMP is discussed.───其次，討論了高分辨率星載SAR輻射定標與衛星運動(dòng)參數的關(guān)聯(lián)技術(shù)。

57 、Measuremeut of Appareut Temperature of Typical Terrestrial Materials aud Radiometric Imaging Experiments at 8.63 mm Wavelength───63毫米波長(cháng)典型地物的視在溫度測量和輻射成象實(shí)驗

58 、The data analysis for FY-2B and FY-2C shows that the South China Sea is a suitable radiometric calibration site for geostationary meteorological satellites.───在分別對FY-2B與FY-2C的測量數據處理后,初步確定我國南海海面可以作為我國靜止氣象衛星在軌輻射定標的場(chǎng)地.

59 、radiometric method───放射測量法

60 、Implement of Solar Photometer Calibration by Transferring of Radiometric Radiator[J].───引用該論文 羅軍,易維寧,何超蘭,彭妮娜.

61 、Comparison and sensitivity analysis of instruments and radiometric methods for LAI estimation: assessments from a boreal forest site───LAI估算的儀器和輻射測量方法較及靈敏度分析:來(lái)自北方森林站點(diǎn)的評估

62 、In-flight radiometric calibration of advanced remote sensing systems───先進(jìn)遙感系統的飛行中輻射定標

63 、Radiometric dating proves this rock is about 450 million years old.─── 放射性定年法證明 這塊巖石大約有4.5億年的歷史

64 、Analytical services include potassium-argon age determinations, stable isotope ratio analyses, radiocarbon age determinations as well as other radiometric analyses.───分析包括鉀-氬測年，穩定同位素豐度分析，放射性碳測年，以及其他放射性分析。

65 、IN-FLIGHT VICARIOUS RADIOMETRIC CALIBRATION FOR VIS-NIR CHANNELS OF FY-1C SATELLITE SENSOR AT DUNHUANG SITE───FY-1C遙感器可見(jiàn)近紅外各通道在軌輻射定標

66 、integrated technologic system based on remote sensing spectrum and airborne radiometric gamma energy spectrum───光-能譜集成技術(shù)系統

67 、A Modified Fitting Algorithm for Radiometric Correction of Sea Surface───改進(jìn)的擬合算法在海面輻射校正中的應用

68 、5. Consequently, radiometric dating has advanced briskly in the past 30 years.───因此，新近三十年來(lái)，放射性計時(shí)迅猛發(fā)展。

69 、A MATHEMATICAL MORPHOLOGICAL FOR EDGE DETECTION IN MILLIMETER WAVE RADIOMETRIC IMAGES───基于數學(xué)形態(tài)學(xué)的毫米波圖像邊緣檢測方法

70 、Discussion on effectiveness of application of air-borne radiometric data to prospecting for non-radioactive metallic mineral resources───應用航放資料尋找非放射性金屬礦產(chǎn)效果探討

71 、radiometric end-point───放射測定終點(diǎn)

72 、Atmospheric and radiometric correction is the basis and key for quantificational remote sensing.───衛星遙感數據的大氣輻射校正是定量遙感的基礎與關(guān)鍵。

73 、radiometric calorimetry───放射量熱法

74 、Keywords sorting;photometric sorting;X-ray sorting;radiometric sorting;───揀選;光電分選;X射線(xiàn)分選、放射性分選;

75 、radiometric sorting───放射性分選

76 、ON-ORBIT RADIOMETRIC CALIBRATION OF FENGYUN GEOSTATIONARY METEOROLOGICAL SATELLITE'S INFRARED CHANNELS BASED ON SEA-SURFACE MEASUREMENTS IN THE SOUTH CHINA SEA───利用南海水面開(kāi)展我國靜止氣象衛星紅外通道在軌輻射定標

77 、radiometric dating───同位素年齡測定放射性測定年代

78 、Multivariate Statistical Integration of Satellite Infrared and Microwave Radiometric Measurements for Rainfall Retrieval at the Geostationary Scale───在對地靜止尺度上的降雨反演人造衛星紅外線(xiàn)和微波輻射儀測量的多變量統計積分

79 、An Automatic and Robust Relative Radiometric Calibration Method for Multitemporal Remote Sensing Images───一種穩健的多時(shí)相遙感圖像相對輻射校正方法

80 、Zhang GK, Chen C, Xing F, Zang HY, Zhao YS.Spectral Radiometric Calibration Research of Quick Bird Digital Image.Spectroscopy and Spectral Analysis(in press).(SCI───張亮,邢福*,劉曉莉.論大學(xué)本科教學(xué)中生態(tài)觀(guān)教育之必要性與實(shí)施途徑.人文學(xué)術(shù)研究,主編王亞范,趙紅,吉林人民出版社,2006,512-516.

81 、Surface radiometric temperature───地表溫度

landsat8影像DN值為什么都那么大？

landsat8數據采用16位16bit才反映DN值，DN范圍在0-65535之間，以前的是8bit的，DN值在0-255，所以不同。不過(guò)DNVI（landsat8）=(b5-b4)/(b5+b4)，而不是以前的4-3波段了，公式需要變的。

你用envi下的DNVI工具可以直接求得DNVI的值，這個(gè)值是最正確的。

同時(shí)影像做NDVI前先大氣校正下，radiometric collebration----flaash。。。做好這兩步在做dnvi即可

The Study of Image Restoration Techniques for Aerial Radiometric Data

Zhang Yu jun

（Research Institute of Areo-Geophysics,Center of Acro-Geophysics and Remote Sensing, Minjstry of Geology and Mineral Resouces,Beijing 100083,China）

This paperpresents a very specific method for restoration of images of airborne radiometric data.High-lights of this paper indude the advancement of the principles and theory, the establishment of the processing flow-diagram, the formulation of the means for reestablishment of the gridded data file, the evaluation of the restoration results and the errors involved.

Key words: Aeroradiometric data, Atmospheric background, Image processing, lmage restoration techniques.

1 INTRODUCTION

Since the adoption of prismatic NaI（T1）crystals in the early 70's, the sensitivity and effectiveness of airbome radiometric surveying have increased significantly.The demands on aerial radiometrics by geologists and geophysicists have also changed.

During the past 20 years, the atmospheric radon background（or atmospheric background for short）could never he accurately corrected.This has been the main problem affecting the successful application of the airborne-radiomctric method.This problem manifests itself through the presence of stripes on maps and this seriously affects the usefulness of these maps.The reason can be summarized[1]as follows: the radioac-tivity measured in the air comes from the earth and also from the airframe itself,from cosmtc radiation and from atmospheric radon and its products.The latter is referred to as the atmospheric background and is influ-enced by changes in the seasonal climate, in the wind-force and wind direction, in the temperature, in the time of the day, etc.The interference of atmospheric background has different levels from flight to flight.The uranium channel suffers the most, the potassium channel is next.Although the thorium channel and the total count channel are least effected, their errors should not be neglected（see Fig.3 and Fig.4 in color plate 7）.As a result of this type of interference, the geologic informationfrom the earth is often masked.Fig.3 a（in color.plate 7）shows the restored image composed of the three elements: K（red）, Th（green）, U（blue）in the Hamitudun survey region.Fig.3 b（colored plate 7）is the composite image of the raw data.Fig.4a（colored plate 7）shows the data taken in the morning and evening for use in the correction of the flight data.Fig.4b（colored plate 7）is the raw data image of thetotal count channel.The existence of the banding noise can be compared to a striped colored veil hanging against the image of useful in-formation.With the presence of this severe noisy disturbance, it is almost impossible to generate any accept able contour maps using the raw radiomctric data from this survey region.

Noise on radiometric maps is a“world-wide”problem[2].The removal of the atmospheric background has been discussed by a number of authors.For regions having many bodies of water, Darnley and Grasty[1]recommended background corrections based on counts collected during frequentflights over large lakes.Foote[3]used an upward-looking detector shielded from ground radiation and multiple flights to estimate the atmospheric radiation in the uranium channel.Later in 1986, Grasty[4]suggested using the average of the normal section of flight line, instead of the background, when no lakes are present in the survey region.

The method introduced here is entirely different from the methods used by others.This method is an image restoration technique for aerial radiometric data.According to digital image processing terminology, image restoration is commonly defined as the reconstruction or estimation of an image field to correct image degradation and to approximate as closely as possible an ideal degradation.freeimagefield by using priori knowledge of degradation.The procedure of restoration is to model the image degradation effects and then perform operations to“undo”the model, producing an image which has been restored to a certain degree.

Dr.Cannon[5]developed a pattern removal technique or image restoration technique with the capability of removing a fingerprint from a regular pattern（fabric）, improved defocusing, capable of overcoming severe detector-to-detector noise on Landsat MSS image, clarification of motion blurred image, and so on.A similar study has been reported by Srinivasan[6].Zhang Yu-jun etal.[7]studied the image restoration problem in photos of deep-sea manganese nodules from the angle of light degradation due to a nonhomogeneous light-source.

The image restoration technique for aerial radiometrie data is a new application of the digital image restoration technique in geology.The degradation of the image of aerial radiometric data is specific and different from the above mentioned instances.This method has been tested and verified in preliminary research for 6 survey regions.

2 PRINCIPLE AND THEORY OF IMAGE RESTORATION TECHNIQUE FOR AERIAL RADIOMETRIC DATA

A degraded image G（x,y）is obtained by aerial radiometric survey.It can be regarded as the sum of the degradation-free ideal image F（x,y）and an interfering imageη（x,y），The degradation process can be simplified and is shown in Fig.1.

Fig.1 Diagram for degradation of imago of aerial radiometric data.

The priori knowledge of degradation for aerial radiometric data image can be obtained by the analysis of an aerial radiometric survey and the raw data image.During the survey,the information originating from the geologic bodies is independent of time,but the interfering signal is essentially time dependent.On the image the interfering signal can be represented as a function of（x, y）asfollows:

but

so

張玉君地質(zhì)勘查新方法研究論文集

張玉君地質(zhì)勘查新方法研究論文集

張玉君地質(zhì)勘查新方法研究論文集

The change ofηcan be divided into two parts: the stepped change between flights and the gradual change within a flight, see Fig.4（in color plate 7）.The interfering signal can be considered as a constant on each flight line T, If x（the column on an image）expoesses the direction perpendicular to the flight line, the functionη（x,y）may be simplified into（x），thus

張玉君地質(zhì)勘查新方法研究論文集

The purpose of restoration of the aerial radiometric image is simply to find an approximateη（x）and to approxjmately obtain the F（x, y）.In this connection, convolution can be conducted several times along the flight line direction for the raw data image using a long narrow window with several lines and a single column,leading to:

張玉君地質(zhì)勘查新方法研究論文集

W is the plate of convolution, and it is a weighting matrix.Convolution is a type of linear operation, the operatorHis space-invariant.Since the operator is linear, the operation is additive.Thus, the response of the sum of two inputs equals the sam of the two respones

張玉君地質(zhì)勘查新方法研究論文集

Since it is assumed that thefunctionηonly correlates with x, and the convolution window is a singlecolumn one,

張玉君地質(zhì)勘查新方法研究論文集

The characteristics of function HF（x, y）will now be examined.Since a smooth average has been performed severaltimes along the y direction, the local anomalies are almost“drowned out”by the appar ent regional features which manifest themselves as a slow change along the flight line.If the local anomaly is expressed byf（x,y）and the apparent regional field byL（x,y），we have

張玉君地質(zhì)勘查新方法研究論文集

after thefollowing process

張玉君地質(zhì)勘查新方法研究論文集

It can be seen from equation（9）that the restored imagef（x,y）which is a result of the raw data image by the substraction of the noise image, closely approximates the ideal image from the point of view of the local anomalies.The error depends on the amplitude of change of the substracted“apparent regional background”along the flight line direction.

3 PROCEDURE FOR RESTORATION HANDLING OF AERIAL RADIOMETRIC DATA IMAGE

The study of the image restoration techniquefor aerial radiometric data is based on the theory of multivariate statistical analysis.It is accomplished by means of image processing.It demonstrates image processing as a directly visual and fast procedure.Its flow-chart is illustrated in Fig.2.

The method assumes that the noise background of aerial radiometric data is non-variable or only linear-ly variable, By a smooth averaging conducted several times along the flight line direction, the local anoma-lies will gradually disappear as they are“drowned out”by the noise background.The resultant noise image is linearly correlated with the noise background and subject to some edge compensation.After the substraction of noise, we conducted a median filtering and a Wallis transformation（space variant contrast stretch）.This finally led to the restoration effect.This restoration process is shown in the left-hand half of Fig.2.

The right-hand half of Fig.2 shows the reconstruction process of the gridded data file, which is indispensable in routine application.After classification and region separation we can get the mean-vectors for all classes before and after restoration.By a least-squares fitting we can obtain the element concentration values or the count-rates for the restored image.A gridded data file for contouring on the main-frame computer can finally be produced by the inverse transformation.

Fig.2　Procedure for restoration of handljng of aerial radiometric data image.

In this investigation we have also tried to get the noise levels by averaging all datafor each flight line, but the results are not as ideal as those gained by the above described method.

4 RESULTS AND ERROR EVALUATION

4.1 ResuIts of the I mage Restoration for AeriaI Radiometric Data

（1）Improved direct visual effect on maps

The image restoration process bears a striking analogy to the drawing aside of a striped colored veil to disclose the original clean features of the gamma-spectrum data that are hidden behind and obscured by the veil（see Fig.3 in color plate 7）.The sawtooth-shaped events occurring on the boundaries of some geologic bodies as aresult of inaccurate positioning of flight lines,bothforward and backward, are also much ameliorated（see Fig.5 in color plate 7）.Fig.5（colored plate 7）displays the comparison imagefor the total count channel:Fig.5a shows the raw data, Fig.5b the noise image,Fig.5c the noise-removed image and Fig.5d illustrates the restored image.

（2）The upgraded contour maps after data restoration

The contour maps of K,Th and U channels from the Hamitudun survey could not be drawn at first on the main-flame computer because of the severe banding interferences in the raw data.Only stacked profiles were supplied for these elements.Although the contour map for the total count channel was drawn,the banding effect was still distinctly visible.

By applying the technique of image restoration and by reconstructing the gridded data files and feeding them back to the main-frame computer,good quality contour maps were produced for TC, K,Th and U.Fig.6（color plate 7）.shows the contour map for K channel after restoration.Its anomalies have a good correlation with the geologic bodies on the geological map.There is also a good agreement between the radioactivities of the anomalies and the lithology.All this proves the effectiveness of this technique.The quality of the contour maps has been significantly upgraded by the process.The accuracy of these maps is further confirmed by the classification map using restored data（see Fig.7 in color plate 7）.In the classification image of Fig.7 there are 9 classes:1.ultrabasic,2.basic,3.granite,4.diorite,5.metamorphic,6.migmatite,7.Quaternary sediments,8.Tertiary and Quaternary sediments and 9.Tertiary sediments.

（3）The enrichment of useful information

Multivariate statistica1analysis has been used in this studyfor the quantitative eva luation of the effectof image restorationfor aerial radiometric data.It is possible to evaluate this effect by the variation of useful information in some images.For this purpose it is necessary to calculate the mean variation,which is the average of the total variation for a single pixel.The symbols C,C´and G" express the mean variations for useful information in the primary image,for the interference information in the primary image andfor the useful information in the restored jmage,respectively.

In the statistics,G´（x,y）is approximately taken asη（x），while[G（x,y）－G´（x,y）]showsF（x,y）approximately,and P（x,y）represents thefinal restored image.It is assumed that there are no errors.

張玉君地質(zhì)勘查新方法研究論文集

The letters with a bar above them indicate the mean values.M,Nstandfor the numbers of lines and columns in an image.

Table 1 illustrates the statistical results for quantitative evaluation by using the above listedformula for the aerial radiometric data images of the Hamitudun survey region.

Table 1 demonstrates the remarkable increase of useful informationfor all the K,Th,U and TC restored images.Speaking about this survey region,the quality of primary images for TC and K channels is better than those for Th and U channels.

Table1　Statistical results for quantitative evaluation of the aerial radiometric data images of the Hamitudun survey region

4.2　The Evaluation of Accuracy and Error for the Restored I mages

The main error in a restored image comes from the“apparent regional background”L（x, y）formed by smooth averaging done several times.The following evaluationfor accuracy was found by the statistics of the profide data on the interfering images.

K±0.16%（absolute concentration）Th±2.1 ppm

U±0.15ppm TC±869.6counts

5 CONCLUSIONS

1.The method described here was suggested in China and overseas as a new specific technique of image restoration for aerial radiometric data.Its reliability and practicability were tested by data in several survey regions.

2.This technique can basically remove the banding noise on,radiometric data maps caused by the changing of atmospheric background and by unstable thresholds.It can basically restore the ideal image of the aerial radiometric data.It also provides preparation for further image processing（such as:enhancement, gradientation,classification,logic operation,etc.）.Therefore,it can be used as a quick method for data pretreatment.

3.This method can improve the sawtooth-shaped noise on the image at the boundaries of some geologic bodies as a result of inaccurate positioning.

4.The mean variation of useful information is suggested in this study as a measure for quantitative evaluation of restoration effects for the aerial radiometric data image.Also discussed in this study is the absolute error or accuracy of the method with which image restoration is used as a pre-treatment process.

ACKNOWLEDGEMENTS

Many people contributed to the success of this work.In particular,I would like to mention Lin Zhen-min for his valuable discussions,Shi Jian-wen for his taking part in the repeated tests,Zhang Zhi-min and Xie Xin who developed the programs for data transformation and least-squaresfitting, Shui En-hai who collected the correction data in the testing region,Lu Lin-sheng,who helped with English,and Li Wei-hua, who typed the text on a word processor.I am very grateful to all of them.

REFERENCES

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[3]Foote,R.S.,Improvement in airborne gamma-radiation data analysis by removal of environ-mental and pedologic radiation changes,in Sympos.on the Use of Nudear Techniques in Prospecting and Development of Mineral Resources: Internat.Atomic Energy Agency Mtg., Buenos Aires, 187-196,1968.

[4]Grasty,R.L.,Automated system for computing on-line atmospheric backgrounds,GSC paper, 1-52,1987.

[5]Cannon,M.,Lehar,A.and Preston,F.,Background pattern removal by power spectral filtering,Applied Optics,22,777-779,1983.

[6]Srinivasan,R.,Software image restoration techniques,Digital Design,16,4,29-34,1986.[7]Zhang Yu-jun and Shi Jian-wen,A study of image reconstruction and image processing techniques for photos of deep-sea polymetallic nodules,Geophysical and Geochemical Exploration（inChinese）13,435-441,1989.

原載《Chinese Journal of Geophysics》，1990,Vol.33,No.3.