期刊文献+
共找到26,440篇文章
< 1 2 250 >
每页显示 20 50 100
Characterization of Aquifers in Crystalline and Crystallophyll Basement Zones Using the Electrical Resistivity Method (Trails and Electrical Soundings) in the Gagnoa Region, (Central-Western Côte d’Ivoire)
1
作者 Oscar Zahibo Onétié Assoué Kouakou Sylvestre Kouadio +1 位作者 Kotchi Rodrigue Orou Maxime Assa Abe 《International Journal of Geosciences》 CAS 2024年第6期511-523,共13页
Introduction: Located in the central-western part of Côte d’Ivoire, the subsoil of the Gagnoa region is made up of sedimentary volcano formations and granitoids with developed fracturing. This complex Precambria... Introduction: Located in the central-western part of Côte d’Ivoire, the subsoil of the Gagnoa region is made up of sedimentary volcano formations and granitoids with developed fracturing. This complex Precambrian basement contains most of the region’s water resources. This is at the origin of the high failure rate during the various hydrogeological prospecting campaigns. Methodology: The database consists of resistivities from 42 holes and 51 trails drilled as part of the implementation of high-throughput drilling in the study area. The objective of this study is to deepen the knowledge of the fissured basement by interpreting profile curves and electrical soundings. It will be a question of classifying the different types of anomalies obtained on the profiles and their shapes. The orientation of the lineaments observed on the profiles was determined. Results: The interpretation of the geophysical data revealed various anomalies, the main ones being of the CC (Conductor Compartment) and CEDP (Contact between two bearings) types. These types of anomalies are mainly expressed in various forms: the “V”, “W” and “U” shapes. From these anomalies and the appearance of the electrical profiles, lineaments and their orientations were identified with N90-100, N130-140, N170-180 as major orientations. Conclusion: These results could contribute to a better understanding of the fractured environment of the Gagnoa region. 展开更多
关键词 BASEMENT Electrical Profiles sounding Curves Resistivities
在线阅读 下载PDF
A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China
2
作者 Fang YUAN Zijiang ZHOU Jie LIAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2192-2202,共11页
High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for ... High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations. 展开更多
关键词 L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting
在线阅读 下载PDF
Corrections of shipboard GPS radiosonde soundings and applications on historical records in the eastern tropical Indian Ocean and South China Sea
3
作者 Zewen Wu Xin Liu +3 位作者 Yunkai He Haoyu Jiang Bo Peng Ke Huang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期54-69,共16页
Shipboard radiosonde soundings are important for detecting and quantifying the multiscale variability of atmosphere-ocean interactions associated with mass exchanges.This study evaluated the accuracies of shipboard Gl... Shipboard radiosonde soundings are important for detecting and quantifying the multiscale variability of atmosphere-ocean interactions associated with mass exchanges.This study evaluated the accuracies of shipboard Global Positioning System(GPS)soundings in the eastern tropical Indian Ocean and South China Sea through a simultaneous balloon-borne inter-comparison of different radiosonde types.Our results indicate that the temperature and relative humidity(RH)measurements of GPS-TanKong(GPS-TK)radiosonde(used at most stations before 2012)have larger biases than those of ChangFeng-06-A(CF-06-A)radiosonde(widely used in current observation)when compared to reference data from Vaisala RS92-SGP radiosonde,with a warm bias of 5℃and dry bias of 10%during daytimes,and a cooling bias of-0.8℃and a moist bias of 6%during nighttime.These systematic biases are primarily attributed to the radiation effects and altitude deviation.An empirical correction algorithm was developed to retrieve the atmospheric temperature and RH profiles.The corrected profiles agree well with that of RS92-SGP,except for uncertainties of CF-06-A in the stratosphere.These correction algorithms were applied to the GPS-TK historical sounding records,reducing biases in the corrected temperature and RH profiles when compared to radio occultation data.The correction of GPS-TK historical records illustrated an improvement in capturing the marine atmospheric structure,with more accurate atmospheric boundary layer height,convective available potential energy,and convective inhibition in the tropical ocean.This study contributes significantly to improving the quality of GPS radiosonde soundings and promotes the sharing of observation in the eastern tropical Indian Ocean and South China Sea. 展开更多
关键词 shipboard GPS radiosonde soundings CORRECTIONS temperature relative humidity eastern tropical Indian Ocean South China Sea
在线阅读 下载PDF
Semi-Active Sound Absorption Method with Acoustic Impedance Matching
4
作者 ZHU Congyun ZHANG Shaoqi DING Guofang 《Journal of Donghua University(English Edition)》 2025年第1期64-70,共7页
The active sound absorption technique excels in mitigating low-frequency sound waves,yet it falls short when dealing with medium and high-frequency sound waves.To enhance the sound-absorbing effect of medium and high-... The active sound absorption technique excels in mitigating low-frequency sound waves,yet it falls short when dealing with medium and high-frequency sound waves.To enhance the sound-absorbing effect of medium and high-frequency sound waves,a novel semi-active sound absorption method has been introduced.This method modulates the surface impedance of a loudspeaker positioned behind the sound-absorbing material,thereby altering the sound absorption coefficient.The theoretical sound absorption coefficient is calculated using MATLAB and compared with the experimental one.Results show that the method can effectively modulates the absorption coefficient in response to varying incident sound wave frequencies,ensuring that it remains at its peak value. 展开更多
关键词 acoustic impedance semi-active sound absorption rigid wall cavity depth sound absorption coefficient
在线阅读 下载PDF
Real-time monitoring of disc cutter wear in tunnel boring machines:A sound and vibration sensor-based approach with machine learning technique
5
作者 Mohammad Amir Akhlaghi Raheb Bagherpour Seyed Hadi Hoseinie 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1700-1722,共23页
Large portions of the tunnel boring machine(TBM)construction cost are attributed to disc cutter consumption,and assessing the disc cutter's wear level can help determine the optimal time to replace the disc cutter... Large portions of the tunnel boring machine(TBM)construction cost are attributed to disc cutter consumption,and assessing the disc cutter's wear level can help determine the optimal time to replace the disc cutter.Therefore,the need to monitor disc cutter wear in real-time has emerged as a technical challenge for TBMs.In this study,real-time disc cutter wear monitoring is developed based on sound and vibration sensors.For this purpose,the microphone and accelerometer were used to record the sound and vibration signals of cutting three different types of rocks with varying abrasions on a laboratory scale.The relationship between disc cutter wear and the sound and vibration signal was determined by comparing the measurements of disc cutter wear with the signal plots for each sample.The features extracted from the signals showed that the sound and vibration signals are impacted by the progression of disc wear during the rock-cutting process.The signal features obtained from the rock-cutting operation were utilized to verify the machine learning techniques.The results showed that the multilayer perceptron(MLP),random subspace-based decision tree(RS-DT),DT,and random forest(RF)methods could predict the wear level of the disc cutter with an accuracy of 0.89,0.951,0.951,and 0.927,respectively.Based on the accuracy of the models and the confusion matrix,it was found that the RS-DT model has the best estimate for predicting the level of disc wear.This research has developed a method that can potentially determine when to replace a tool and assess disc wear in real-time. 展开更多
关键词 TBM disc cutter WEAR sound VIBRATION Machine learning Real-time wear estimation
在线阅读 下载PDF
A WKB method based on parabolic cylinder function for very-low-frequency sound propagation in deep ocean
6
作者 Jian-Kang Zhan Sheng-Chun Piao +3 位作者 Li-Jia Gong Yang Dong Yong-Chao Guo Guang-Xue Zheng 《Chinese Physics B》 2025年第3期433-446,共14页
A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the re... A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the reference functions method to describe the solution to the depth-separated wave equation approximately using parabolic cylinder functions.The conditions for the validity of this approximation are also discussed.Furthermore,a formula that incorporates waveguide effects for the modal group velocity is derived,revealing that boundary effects at very low frequencies can have a significant impact on the propagation characteristics of even low-order normal modes.The present method not only offers improved accuracy compared to the classical WKB approximation and the uniform asymptotic approximation based on Airy functions,but also provides a wider range of depth applicability.Additionally,this method exhibits strong agreement with numerical methods and offers valuable physical insights.Finally,the method is applied to the study of very-low-frequency sound propagation in the South China Sea,leading to sound transmission loss predictions that closely align with experimental observations. 展开更多
关键词 WKB method normal modes very-low-frequency sound propagation parabolic cylinder function
在线阅读 下载PDF
Development of multi-channel observation and inversion for IP electrical sounding method 被引量:5
7
作者 刘海飞 柳建新 +3 位作者 郭荣文 童孝忠 龚露 彭艳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期816-823,共8页
In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are s... In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are studied. First of all, four multi-channel observation methods are developed based on conventional IP electrical method, namely three-electrode and four-electrode arrays of unilateral and bilateral current transmitting. Then the maximum smoothness constrained inversion method of the least squares sense for IP electrical sounding data is proposed, and the inversion software is programmed. Finally, the simulation and inversion results of geo-electrical model for the proposed observation methods are analyzed. And the comparison results show that three-electrode array of bilateral current transmitting gives the best result, but the intensity in field work is larger than others; unilateral three-electrode and four-electrode arrays give the better results. Taking detection results and convenience of field exploration work into consideration, these two methods are more suitable for practical application; bilateral observation method of four-electrode array is not suitable for the detection of the steep ore bodies. 展开更多
关键词 IP electrica-1 sounding multi-channel observation deep exploration inversion imaging
在线阅读 下载PDF
Comparison and Analysis between Two Types of Sounding Data of China
8
作者 陈哲 臧海佳 《Agricultural Science & Technology》 CAS 2009年第6期175-177,共3页
The upper air weather forecast data used in current business and research and digital data of the recently finished upper air meteorological monthly report were comparatively analyzed in complete data and quality cond... The upper air weather forecast data used in current business and research and digital data of the recently finished upper air meteorological monthly report were comparatively analyzed in complete data and quality condition of data, and sounding curve change caused by the difference of complete data was also compared, which evaluated advantages and disadvantages of two types of data. 展开更多
关键词 sounding Coded messages for upper-level data Monthly tables of sounding
在线阅读 下载PDF
Crustal Structure Revealed by a Deep Seismic Sounding Profile of Baijing-Gaoming-Jinwan in the Pearl River Delta 被引量:11
9
作者 ZHANG Xiang YE Xiuwei +2 位作者 LV Jinshui SUN Jinlong WANG Xiaona 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第1期186-194,共9页
The Pearl River Estuary area, located in the middle part of the southern China coastal seismic belt, has long been considered a potential source of strong earthquakes above magnitude 7.0. To scientifically assess the ... The Pearl River Estuary area, located in the middle part of the southern China coastal seismic belt, has long been considered a potential source of strong earthquakes above magnitude 7.0. To scientifically assess the potential strong earthquake risk in this area, a three-dimensional artificial seismic sounding experiment, consisting of a receiving array and seabed seismograph, was performed to reveal the deep crustal structure in this region. We used artificial ship-borne air-gun excitation shots as sources, and fixed and mobile stations as receivers to record seismic data from May to August 2015. This paper presents results along a line from the western side of the Pearl River Estuary to the western side of the Baijing-Gaoming-Jinwan profile. A two-dimensional velocity structure was constructed using seismic travel-time tomography. The inversion results show that the Moho depth is 27 km in the coastal area and 30 km in the northwest of the Pearl River Estuary area, indicating that the crust thins from land to sea. Two structural discontinuities and multiple low-velocity anomalies appear in the crustal section. Inside both discontinuity zones, a low-velocity layer, with a minimum velocity of 6.05 km s^(-1), exists at a depth of about 15 km, and another, with a minimum velocity of 6.37 km s^(-1), exists at a depth of about 21.5 km between the middle and lower crust. These low velocities suggest that the discontinuities may consist of partly molten material. Earthquakes with magnitudes higher than 5.0 occurred in the low-velocity layer along the profile. The deep Kaiping-Enping fault, rooted in the crust, may be one of the most important channels for deep material upwelling and is related to tectonic movement since the Cretaceous in the Pearl River Delta tectonic rift basin. 展开更多
关键词 PEARL River Estuary seismic sounding PROFILE CRUSTAL structure Kaiping-Enping fault earthquake potential
在线阅读 下载PDF
A New Infrared Atmospheric Sounding Interferometer Channel Selection and Assessment of Its Impact on Met Office NWP Forecasts 被引量:8
10
作者 Young-Chan NOH Byung-Ju SOHN. +3 位作者 Yoonjae KIM Sangwon JOO William BELL Roger SAUNDERS 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第11期1265-1281,共17页
A new set of Infrared Atmospheric Sounding Interferometer (IASI) channels was re-selected from 314 EUMETSAT channels. In selecting channels, we calculated the impact of the individually added channel on the improvem... A new set of Infrared Atmospheric Sounding Interferometer (IASI) channels was re-selected from 314 EUMETSAT channels. In selecting channels, we calculated the impact of the individually added channel on the improvement in the analysis outputs from a one-dimensional variational analysis (1D-Var) for the Unified Model (UM) data assimilation system at the Met Office, using the channel score index (CSI) as a figure of merit. Then, 200 channels were selected in order by counting each individual channel's CSI contribution. Compared with the operationally used 183 channels for the UM at the Met Office, the new set shares 149 channels, while the other 51 channels are new. Also examined is the selection from the entropy reduction method with the same 1D-Var approach, Results suggest that channel selection can be made in a more objective fashion using the proposed CSI method. This is because the most important channels can be selected across the whole IASI observation spectrum. In the experimental trial runs using the UM global assimilation system, the new channels had an overall neutral impact in terms of improvement in forecasts, as compared with results from the operational channels. However, upper-tropospheric moist biases shown in the control run with operational channels were significantly reduced in the experimental trial with the newly selected channels. The reduction of moist biases was mainly due to the additional water vapor channels, which are sensitive to the upper-tropospheric water vapor. 展开更多
关键词 Hyperspectral IR sounding channel selection 1D-Vat data assimilation
在线阅读 下载PDF
Bathymetry predicted from vertical gravity gradient anomalies and ship soundings 被引量:10
11
作者 Hu Minzhang Li Jiancheng +1 位作者 Li Hui Xin Lelin 《Geodesy and Geodynamics》 2014年第1期41-46,共6页
In this paper, the admittance function between seafloor undulations and vertical gravity gradient anomalies was derived. Based on this admittance function, the bathymetry model of 1 minute resolution was predicted fro... In this paper, the admittance function between seafloor undulations and vertical gravity gradient anomalies was derived. Based on this admittance function, the bathymetry model of 1 minute resolution was predicted from vertical gravity gradient anomalies and ship soundings in the experimental area from the northwest Pacific. The accuracy of the model is evaluated using ship soundings and existing models, including ETOPO1, GEBCO, DTU10 and V15.1 from SIO. The model's STD is 69. 481m, comparable with V15.1 which is generally believed to have the highest accuracy. 展开更多
关键词 BATHYMETRY vertical gravity gradient admittance function ship soundings ISOSTASY
在线阅读 下载PDF
AN ALGORITHM FOR AUTOMATIC CARTOGRAPHIC SOUNDING SELECTION 被引量:2
12
作者 Sui Haigang Cheng Penggen +1 位作者 Zhang Anming Gong Jianya 《Geo-Spatial Information Science》 1999年第1期96-99,共4页
Soundings on nautical charts provide information about the shape of ocean bottom between chart depth curves. A single chart may have thousands of soundings posted on it. This paper describes a new algorithm for select... Soundings on nautical charts provide information about the shape of ocean bottom between chart depth curves. A single chart may have thousands of soundings posted on it. This paper describes a new algorithm for selecting soundings automatically. At first,the problem encountered in automatic cartographic sounding selection is presented. Then the authors give the principle of the new algorithm,and the implementation is illuminated in detail. At last the experiments prove the rationality and efficiency of the new algorithm. 展开更多
关键词 sounding AUTOMATIC sounding SELECTION DEPTH CURVES influence circle TIN
在线阅读 下载PDF
Use of Total Precipitable Water Classification of A Priori Error and Quality Control in Atmospheric Temperature and Water Vapor Sounding Retrieval 被引量:4
13
作者 Eun-Han KWON Elisabeth WEISZ 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第2期263-273,共11页
This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared ... This study investigates the use of dynamic a priori error information according to atmospheric moistness and the use of quality controls in temperature and water vapor profile retrievals from hyperspectral infrared (IR) sounders. Temperature and water vapor profiles are retrieved from Atmospheric InfraRed Sounder (AIRS) radiance measurements by applying a physical iterative method using regression retrieval as the first guess. Based on the dependency of first-guess errors on the degree of atmospheric moistness, the a priori first-guess errors classified by total precipitable water (TPW) are applied in the AIRS physical retrieval procedure. Compared to the retrieval results from a fixed a priori error, boundary layer moisture retrievals appear to be improved via TPW classification of a priori first-guess errors. Six quality control (QC) tests, which check non-converged or bad retrievals, large residuals, high terrain and desert areas, and large temperature and moisture deviations from the first guess regression retrieval, are also applied in the AIRS physical retrievals. Significantly large errors are found for the retrievals rejected by these six QCs, and the retrieval errors are substantially reduced via QC over land, which suggest the usefulness and high impact of the QCs, especially over land. In conclusion, the use of dynamic a priori error information according to atmospheric moistness, and the use of appropriate QCs dealing with the geographical information and the deviation from the first-guess as well as the conventional inverse performance are suggested to improve temperature and moisture retrievals and their applications. 展开更多
关键词 atmospheric sounding AIRS total precipitable water a priori error quality control
在线阅读 下载PDF
Deep seismic sounding investigation into the deep structure of the magma system in Changbaishan-Tianchi volcanic region 被引量:6
14
作者 张先康 张成科 +7 位作者 赵金仁 杨卓欣 李松林 张建狮 刘宝峰 成双喜 孙国伟 潘素珍 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第2期143-151,共9页
The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly ... The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly characterized by low velocity of P wave, can be divided into three parts in terms of depth. At the depth range of 9-15 km, the distribution of the magma system is characterized by extensiveness, large scale and near-SN orientation. This layer is the major place for magma storage. From the depth of 15 km down to the lower crust, it is characterized by small lateral scale, which indicates the 'trace' of magma intrusion from the upper mantle into the crust and also implies that the magma system most probably extends to the upper mantle, or even deeper.(less than 8-9 km deep), the range of magma distribution is even smaller, centering on an SN-oriented area just north of the Tianchi crater. If low velocity of P wave is related to the magma system, it then reflects that the magma here is still in a state of relatively high temperature. In this sense, the magma system of Changbaishan-Tianchi volcanic region is at least not 'remains', in other words, it is in an 'active' state. 展开更多
关键词 Changbaishan-Tianchi volcanic region 3-D deep seismic sounding magma system
在线阅读 下载PDF
Analysis of Atmospheric Boundary Layer Height Characteristics over the Arctic Ocean Using the Aircraft and GPS Soundings 被引量:14
15
作者 DAI Cheng-Ying GAO Zhi-Qiu +1 位作者 WANG Qing CHENG Gang 《Atmospheric and Oceanic Science Letters》 2011年第2期124-130,共7页
Utilizing aircraft sounding data collected from the Surface Heat Budget of the Arctic Ocean (SHEBA, 1998) campaign, the authors evaluated commonly-used profile methods for Arctic ABL height estimation by validating ag... Utilizing aircraft sounding data collected from the Surface Heat Budget of the Arctic Ocean (SHEBA, 1998) campaign, the authors evaluated commonly-used profile methods for Arctic ABL height estimation by validating against the'true'ABL height from aircraft sounding profiles, where ABL height is defined as the top of the layer with significant turbulence. Furthermore, the best performing method was used to estimate ABL height from the one-year GPS soundings obtained during SHEBA (October 1997-October 1998). It was found that the temperature gradient method produces a reliable estimate of ABL height. Additionally, the authors determined optimal threshold values of temperature gradient for stable boundary layer (SBL) and convective boundary layer (CBL) to be 6.5 K/100 m and 1.0 K/100 m, respectively. The maximum ABL height during the year was 1150 m occurred in May. Median values of Arctic ABL height in May, June, July, and August were 400 m, 430 m, 180 m, and 320 m, respectively. Arctic ABL heights are clearly higher in the spring than in the summer. 展开更多
关键词 aircraft sounding Arctic boundary layer boundary layer height GPS sounding turbulence
在线阅读 下载PDF
Study on the detection of abnormal sounding data based on LS-SVM 被引量:3
16
作者 HUANG Xianyuan ZHAI Guojun +1 位作者 SUI Lifen CHAI Hongzhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第6期115-120,共6页
A new method of detecting abnormal sounding data based on LS-SVM is presented.The theorem proves that the trend surface filter is the especial result of LS-SVM.In order to depict the relationship of trend surface filt... A new method of detecting abnormal sounding data based on LS-SVM is presented.The theorem proves that the trend surface filter is the especial result of LS-SVM.In order to depict the relationship of trend surface filter and LS-SVM,a contrast is given.The example shows that abnormal sounding data could be detected effectively by LS-SVM when the training samples and kernel function are reasonable. 展开更多
关键词 LS-SVM trend surface filter kernel function abnormal sounding data
在线阅读 下载PDF
Sunglint Impact on Atmospheric Soundings from Hyperspectral Resolution Infrared Radiances 被引量:1
17
作者 姚志刚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第3期455-463,共9页
The mid-wave infrared band (3-5 #rn) has been widely used for atmospheric soundings. The sunglint impact on the atmospheric parameter retrieval using this band has been neglected because the reflected radiances in t... The mid-wave infrared band (3-5 #rn) has been widely used for atmospheric soundings. The sunglint impact on the atmospheric parameter retrieval using this band has been neglected because the reflected radiances in this band are significantly less than those in the visible band. In this study, an investigation of sunglint impact on the atmospheric soundings was conducted with Atmospheric InfraRed Sounder ob- servation data from 1 July to 7 July 2007 over the Atlantic Ocean. The impact of sunglint can lead to a brightness temperature increase of 1.0 K for the surface sensitive sounding channels near 4.58 #m. This contamination can indirectly cause a positive bias of 4 g kg-1 in the water vapor retrieval near the ocean surface, and it can be corrected by simply excluding those contaminated channels. 展开更多
关键词 atmospheric sounding hyperspectral resolution infrared radiances sunglint
在线阅读 下载PDF
The application of the high-frequency electromagnetic sounding method in the exploration of underground thermal water 被引量:4
18
作者 Cao Hui He Lanfang +1 位作者 He Zhanxiang Zhao Xiaoming 《Applied Geophysics》 SCIE CSCD 2006年第4期248-254,共7页
High-frequency electromagnetic sounding is an electromagnetic exploration method using the natural high-frequency electromagnetic field as a field source. It has higher resolution and greater depth penetration than th... High-frequency electromagnetic sounding is an electromagnetic exploration method using the natural high-frequency electromagnetic field as a field source. It has higher resolution and greater depth penetration than the direct current method and is especially fit for geothermal energy exploration and low- and mid-level groundwater detection. We introduce a successful application of high-frequency electromagnetic sounding for evaluating geothermal water resources. The high frequency electromagnetic system (MT-USA with a frequency range from 10 KHz to 1 Hz) is first applied to sample field data from China. A remote reference station is used to assure sampled data quality. We then perform 2D inversion image processing with the electrical method data. The results basically indicate the spatial distribution of underground geothermal water and provide favorable clues to finding the sources of the subsurface geothermal water in this area. 展开更多
关键词 High-frequency electromagnetic sounding geothermal resource groundwater exploration.
在线阅读 下载PDF
A Miniature Robotic Plane Meteorological Sounding System 被引量:1
19
作者 马舒庆 陈洪滨 +2 位作者 汪改 潘毅 李强 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第6期890-896,共7页
This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control sys... This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control system, and a ground-based system. Take-o? and landing of the miniature aircraft are guided by radio control, and the ?ight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all ?ight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of ?ight for atmospheric sounding. 展开更多
关键词 miniature Unmanned Aerial Vehicle atmospheric sounding Flight test
在线阅读 下载PDF
Genetic algorithm in seismic waveform inversion and its application in deep seismic sounding data interpretation 被引量:1
20
作者 王夫运 张先康 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第2期163-172,共10页
A genetic algorithm of body waveform inversion is presented for better understanding of crustal and upper mantle structures with deep seismic sounding (DSS) waveform data. General reflection and transmission synthet... A genetic algorithm of body waveform inversion is presented for better understanding of crustal and upper mantle structures with deep seismic sounding (DSS) waveform data. General reflection and transmission synthetic seismogram algorithm, which is capable of calculating the response of thin alternating high and low velocity layers, is applied as a solution for forward modeling, and the genetic algorithm is used to find the optimal solution of the inverse problem. Numerical tests suggest that the method has the capability of resolving low-velocity layers, thin alternating high and low velocity layers, and noise suppression. Waveform inversion using P-wave records from Zeku, Xiahe and Lintao shots in the seismic wide-angle reflection/refraction survey along northeastern Qinghai-Xizang (Tibeteau) Plateau has revealed fine structures of the bottom of the upper crust and alternating layers in the middle/lower crust and topmost upper mantle. 展开更多
关键词 genetic algorithm waveform inversion numerical test deep seismic sounding fine crustal structure
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部