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The environmental analysis and site selection of mussel and large yellow croaker aquaculture areas based on high resolution remote sensing
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作者 Lina Cai Jie Yin +3 位作者 Xiaojun Yan Yongdong Zhou Rong Tang Menghan Yu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期66-86,共21页
Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was propose... Mussel aquaculture and large yellow croaker aquaculture areas and their environmental characteristics in Zhoushan were analyzed using satellite data and in-situ surveys.A new two-step remote sensing method was proposed and applied to determine the basic environmental characteristics of the best mussel and large yellow croaker aquaculture areas.This methodology includes the first step of extraction of the location distribution and the second step of the extraction of internal environmental factors.The fishery ranching index(FRI1,FRI2)was established to extract the mussel and the large yellow croaker aquaculture area in Zhoushan,using Gaofen-1(GF-1)and Gaofen-6(GF-6)satellite data with a special resolution of 2 m.In the second step,the environmental factors such as sea surface temperature(SST),chlorophyll a(Chl-a)concentration,current and tide,suspended sediment concentration(SSC)in mussel aquaculture area and large yellow croaker aquaculture area were extracted and analyzed in detail.The results show the following three points.(1)For the extraction of the mussel aquaculture area,FRI1 and FRI2 are complementary,and the combination of FRI1 and FRI2 is suitable to extract the mussel aquaculture area.As for the large yellow croaker aquaculture area extraction,FRI2 is suitable.(2)Mussel aquaculture and the large yellow croaker aquaculture area in Zhoushan are mainly located on the side near the islands that are away from the eastern open waters.The water environment factor template suitable for mussel and large yellow croaker aquaculture was determined.(3)This two-step remote sensing method can be used for the preliminary screening of potential site selection for the mussels and large yellow croaker aquaculture area in the future.the fishery ranching index(FRI1,FRI2)in this paper can be applied to extract the mussel and large yellow croaker aquaculture areas in coastal waters around the world. 展开更多
关键词 mussel aquaculture area large yellow croaker aquaculture area high resolution satellite site selection environmental analysis
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Earthquake-triggered landslide interpretation model of high resolution remote sensing imageries based on bag of visual word
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作者 Ruyue Bai Zegen Wang +7 位作者 Heng Lu Chen Chen Xiuju Liu Guohao Deng Qiang He Zhiming Ren Bin Ding Xin Ye 《Earthquake Research Advances》 CSCD 2023年第2期39-45,共7页
Traditional visual interpretation is often inefficient due to its excessively workload professional knowledge and strong subjectivity.Therefore,building an automatic interpretation model on high spatial resolution rem... Traditional visual interpretation is often inefficient due to its excessively workload professional knowledge and strong subjectivity.Therefore,building an automatic interpretation model on high spatial resolution remote sensing images is the key to the quick and efficient interpretation of earthquake-triggered landslides.Aiming at addressing this problem,a landslide interpretation model of high-resolution images based on bag of visual word(BoVW)feature was proposed.The high-resolution images were pre-processed,and then BoVW feature and support vector machine(SVM)was adopted to establish an automatic landslide interpretation model.This model was further compared with the currently widely used Histogram of Oriented Gradient(HoG)feature extraction model.In order to test the effectiveness of the method,typical landslide images were selected to construct a landslide sample library,which was subsequently utilized as the foundation for conducting an experimental study.The results show that the accuracy of landslide extraction using this method reaches as high as 89%,indicating that the method can be used for the automatic interpretation of landslides in disaster-prone areas,and has high practical value for regional disaster prevention and damage reduction. 展开更多
关键词 Earthquake-triggered landslide BoVW high resolution imagery Interpretation model
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Archean Basement and a Paleoproterozoic Collision Orogen in the Huoqiu Area at the Southeastern Margin of North China Craton: Evidence from Sensitive High Resolution Ion Micro-Probe U-Pb Zircon Geochronology 被引量:36
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作者 WAN Yusheng DONG Chunyan WANG Wei XIE Hangqiang LIU Dunyi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第1期91-104,共14页
This paper reports sensitive high resolution ion micro-probe U-Pb zircon ages for the "Huoqiu Group" and granitoids of the Early Precambrian basement in the Huoqiu area, southeastern margin of the North China Craton... This paper reports sensitive high resolution ion micro-probe U-Pb zircon ages for the "Huoqiu Group" and granitoids of the Early Precambrian basement in the Huoqiu area, southeastern margin of the North China Craton. The "Huoqiu Group" is similar in rock association and metamorphism to the khondalite series, apart from it containing considerable amounts of banded iron formation. All detrital zircons from the "Huoqiu Group" meta-sedimentary rocks are 3.0 Ga and 2.75 Ga, without any 2.5 Ga and younger ones, as is commonly found in Paleoproterozoic khondalite series in other areas of the North China Craton. In the Huoqiu area, 2.75 Ga and 2.56 Ga granitoids have also been identified. This basement assemblage underwent strong metamorphism during the late Paleoproterozoic (-1.84 Ga) tectonothermal event that is widely developed in the North China Craton. Thus the formation time of the "Huoqiu Group" can be constrained between 2.75 and 1.84 Ga in terms of detrital and metamorphic zircon ages. It is considered, combined with regional data, that there may be a Paleoproterozoic collision orogen extending in a NWW-SEE direction to the southern margin of the North China Craton. 展开更多
关键词 khondalite series trondhjemite-tonalite-granodiorite sensitive high resolution ion micro-probe U-Pb dating ARCHEAN PALEOPROTEROZOIC collision orogen North China Craton
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Quantification of trace amounts of impurities in high purity cobalt by high resolution inductively coupled plasma mass spectrometry 被引量:10
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作者 XIE Hualin HUANG Kelong +1 位作者 NIE Xidu TANG Yougen 《Rare Metals》 SCIE EI CAS CSCD 2007年第3期286-291,共6页
A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, ... A An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of 24 elements (Be, Mg, A1, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn Sb, Ba, Pt, Au, and Pb) in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCI. The matrix effects because of the presence of excess HCI and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits were 0.016-1.50 ].tg·g^-1, the recovery ratios were 92.2%-111.2%, and the RSD was less than 3.6%. The method was accurate, quick, and convenient. It was applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 high resolution inductively coupled plasma mass spectrometry high purity cobalt trace impurities matrix effect standard addition method
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Technical foundation research on high resolution remote sensing system of China's coastal zone 被引量:9
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作者 YANGXiaomei LANRongqin +1 位作者 DUYunyan CHENXiufa 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第1期109-118,共10页
China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic ... China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic development and modern management.Laying a theoretical foundation for the modern management of China's costal zone is aimed at. This research focuses on the following processing and analyzing technologies for coastal zone high-resolution remote sensing data: organization and management of large amounts of high-resolution remote sensing data, quick and precise spatial positioning system,algorithms for image fusion in feature level and coastal zone feature extraction. They will form a technical foundation of the system. And, if combined with other research results such as coastal zone remote sensing classification system and its mapping subsystem, an advanced technical frame for remote sensing investigation of coastal zone resource will be constructed. 展开更多
关键词 China's coastal zone high resolution remote sensing technical platform
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Radar high resolution range profile recognition via multi-SV method 被引量:5
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作者 Long Li Zheng Liu Tao Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第5期879-889,共11页
For radar high resolution range profile (HRRP) recognition, three aspects are of great importance to improve the performance, i.e. discrimination for outlier, classification for inner and an accurate description for f... For radar high resolution range profile (HRRP) recognition, three aspects are of great importance to improve the performance, i.e. discrimination for outlier, classification for inner and an accurate description for feature space. To tackle these issues, a novel target recognition method is designed, denoted by the multiple support vectors (multi-SV) method. With the proposed method, a special framework is constructed by a treble correlate support vector model to segment the feature space to two regions with the distribution of density, and then the description and classification hyperplane for each region are achieved. Based on the support vector framework, this method needs less memory and computation complexity to fit practical radar HRRP recognition. Finally, the experiment based on the measured data verifies the excellent performance of this method. 展开更多
关键词 radar target recognition high resolution range profile support vector DISCRIMINATION CLASSIFICATION
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High resolution range profile analysis based on multicarrier phase-coded waveforms of OFDM radar 被引量:5
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作者 Kai Huo Bin Deng Yongxiang Liu Weidong Jiang Junjie Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第3期421-427,共7页
Orthogonal frequency division multiplexing(OFDM) radar with multicarrier phase-coded waveforms has been recently introduced to achieve high range resolution.The conventional method for obtaining the high resolution ... Orthogonal frequency division multiplexing(OFDM) radar with multicarrier phase-coded waveforms has been recently introduced to achieve high range resolution.The conventional method for obtaining the high resolution range profile(HRRP) is based on matched filters.A method of synthesizing HRRP based on the fast Fourier transform(FFT) and decoding is proposed.The mathematical expressions of HRRP are derived by assuming an elementary scenario of point-scattering targets.Based on the characteristic of OFDM multicarrier signals,it mainly analyzes the influence on HRRP exerted by several factors,such as velocity compensation errors,the sampling frequency offset,and so on.The conclusions are significant for the design of the OFDM imaging radar.Finally,the simulation results demonstrate the validity of the conclusions. 展开更多
关键词 orthogonal frequency division multiplexing(OFDM) high resolution range profile(HRRP) MULTICARRIER phase-coded frequency offset.
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A 23.75-GHz frequency comb with two low-finesse filtering cavities in series for high resolution spectroscopy 被引量:3
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作者 侯磊 韩海年 +4 位作者 王薇 张龙 庞利辉 李德华 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期202-206,共5页
A laser frequency comb with several tens GHz level is demonstrated,based on a Yb-doped femtosecond fiber laser and two low-finesse Fabry-Perot cavities(FPCs) in series.The original 250-MHz mode-line-spacing of the s... A laser frequency comb with several tens GHz level is demonstrated,based on a Yb-doped femtosecond fiber laser and two low-finesse Fabry-Perot cavities(FPCs) in series.The original 250-MHz mode-line-spacing of the source comb is filtered to 4.75 GHz and 23.75 GHz,respectively.According to the multi-beam interferences theory of FPC,the side-mode suppression rate of FPC schemes is in good agreement with our own theoretical results from 27 dB of a single FPC to43 dB of paired FPCs.To maintain long-term stable operation and determine the absolute frequency mode number in the23.75-GHz comb,the Pound-Drever-Hall(PDH) locking technology is utilized.Such stable tens GHz frequency combs have important applications in calibrating astronomical spectrographs with high resolution. 展开更多
关键词 laser frequency comb Fabry-P6rot cavity high repetition rate high resolution spectroscopy
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Quantification of Trace Amounts of Impurities in High Purity Cobalt by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:3
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作者 Hua Lin XIE Xi Du NIE You Gen TANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第8期1077-1080,共4页
An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, ... An analytical method using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) for rapid simultaneous determination of Be, Mg, Al, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, As, Se, Mo, Ag, Cd, Sn, Sb, Ba, Pt, Au and Pb in high purity cobalt was described. Sample digestions were performed in closed microwave vessels using HNO3 and HCl. The matrix effects due to the presence of excess HCl and Co were evaluated. The usefulness of high mass resolution for overcoming some spectral interference was demonstrated. The optimum conditions for the determination was tested and discussed. Correction for matrix effects, Sc, Rh and Bi were used as internal standards. The detection limits is 0.003-0.57 μg/g, the recovery ratio is 92.2%-111.2%, and the RSD is less than 3.6%. The method is accurate, quick and convenient. It has been applied to the determination of trace impurities in high purity cobalt with satisfactory results. 展开更多
关键词 high resolution inductively coupled plasma mass spectrometry high purity cobalt trace impurities matrix effect spectral interference internal standards.
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The application of very high resolution satellite image in urban vegetation cover investigation:a case study of Xiamen City 被引量:4
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作者 CHENG Chengqi,Li Bin,MA Ting(Institute of Remote Sensing & GIS, Peking University, Beijing 100871, China) 《Journal of Geographical Sciences》 SCIE CSCD 2003年第3期265-270,共6页
With the technological improvements of satellite sensors, we will acquire more information about the earth so that we have reached a new application epoch of observation on earth environmental change... With the technological improvements of satellite sensors, we will acquire more information about the earth so that we have reached a new application epoch of observation on earth environmental change and cartography. But with the enhancement of spatial resolution, some questions have arisen in the application of using traditional image processing and classification methods. Aiming for such questions, we studied the application of IKONOS very high resolution image (1 m) in Xiamen City on Urban Vegetation Cover Investigation and discussed the difference between the very high resolution image and traditional low spatial resolution image at classification, information abstraction etc. It is an advantageous test for the large-scale application of very high resolution data in the future. 展开更多
关键词 high resolution remote sensing vegetation cover investigation
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HIGH RESOLUTION STUDY OF TWINS IN Al_(20)Cu_2Mn_3 PHASE 被引量:2
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作者 LI Chunzhi WANG Shuncai JIN Yan Institute of Aeronautical Materials,Beijing,Laboratory of Atomic Imaging of Solids,Institute of Metal Research,Academia Sinica,Shenyang,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第4期227-230,共4页
The dispersoid phase Al_(20)Cu_2Mn_3 in a 2024 Al alloy is commonly composed of twins,An ob- servation of corresponding high resolution image shows that the twin boundary plane is a glide plane other than mirror one.T... The dispersoid phase Al_(20)Cu_2Mn_3 in a 2024 Al alloy is commonly composed of twins,An ob- servation of corresponding high resolution image shows that the twin boundary plane is a glide plane other than mirror one.Two neighbouring components of twins are not symmetry of re- flection or rotation,but of glide reflection.The“diamond”glide plane is(101)and the glide vector is(1/4)(-).Components of twins in the phase take shape of prism with the longitudinal edge being parallel to[010]and side faces being{101}and{100}. 展开更多
关键词 TWIN glide reflection high resolution image Al-Cu-Mn alloy
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Direct Determination of Trace Impurities in High Purity Zinc Oxide by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:2
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作者 谢华林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第2期28-32,共5页
The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry ( HR-ICP-MS ) was investigated. To overcome some poteutially problematic spectral iuter... The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry ( HR-ICP-MS ) was investigated. To overcome some poteutially problematic spectral iuterference, measurements were acquired in both middle and high resolution modes. The matrix effects due to the presence of excess HCl and zinc were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits ranged from 0.02μg/ g to 6 μg/ g depending on the elements. The experimental resalts for the determination of Na, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Mo, Cd, Sb and Pb in several high purity zinc oxide powders were presented. 展开更多
关键词 high purity zinc oxide trace impurities high resolution inductively coupled plasma mass spectrometry spectral interferences microwave digestion
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Detection with High Resolution Radar: Advanced Topics & Potential Applications 被引量:2
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作者 Alfonso Farina Flavio A.Studer ALENIA S.p.A. 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第1期21-34,共14页
In a previous companion paper [1], the potential advantages of high resolution radar for improved target detection were introduced. In particular, the concept of shaping both the transmitted waveform and the receiving... In a previous companion paper [1], the potential advantages of high resolution radar for improved target detection were introduced. In particular, the concept of shaping both the transmitted waveform and the receiving processor in accordance to the expected target down-range profile was highlighted and performance predictions were provided. In this paper, we present and evaluate an adaptive scheme devised to on-line estimate the target profile, in order to overcome a limited a-priori knowledge. In addition, we introduce a more general model of target impulse response, based on a statistical description, and we discuss the corresponding processing scheme and detection performance. 展开更多
关键词 high resolution radar Radar detection Adaptive imaging Design criteria.
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Experimental Study on Effect of Compound Biejia Ruangan Prescription (复方鳖甲软肝方) on High Resolution Computerized Tomographic Images in Bleomycin Induced Pulmonary Fibrosis Rats 被引量:2
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作者 张东伟 王继峰 +2 位作者 牛建昭 高宝华 李贡宇 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第4期270-275,共6页
Objective: To study the therapeutic effect of Com pound Biejia Ruangan prescription (CBRP) on rat model with pulmonary fibrosis in duced by bleomycin. Methods: Fifty four male Sprague Dawley rats were rando mly divide... Objective: To study the therapeutic effect of Com pound Biejia Ruangan prescription (CBRP) on rat model with pulmonary fibrosis in duced by bleomycin. Methods: Fifty four male Sprague Dawley rats were rando mly divided into 6 groups (9 rats in each group). From the first day to the 28th day of the experiment, except to those in the sham model control group that were treated with normal saline, the same amount of bleomycin injection as the n ormal saline given to the control group was given through endotracheal instillat ion to all the rats in all the other groups. From the 29th day of the modeling, CBRP solution of different dosages was respectively injected into the rats in th e high, moderate and low CBRP dose group, while equal volume of normal saline w as given to those in the sham model control group and the model control group , and an equal volume of prednisone solution was given to rats in the prednisone group. On the 80th day, the high resolution computerized tomographic (HRCT) images were observed on an equal footing, and HRCT pathology was correlativel y studied. Results: Different HRCT pathological changes were shown in th e rats with pulmonary fibrosis, such as lung consolidation, thickening of interl obular septum and interlobular mesenchyma as well as lobular deformation, nodule shadow, abnormal brochiovascular tract, thickened pleura with irregular junctio n and polished glass like dense shadows. Honeycomb lung was observed in some cases. Pathological sections showed fibrotic proliferation of lung tissues and noticeable pulmonary interstitial fibrosis. CBRP could improve HRCT images of rats with pulmonary fibrosis, and lower fibrotic p roliferation of the lung tissue.Conclusion: CBRP plays its therapeutic role possibly through its effect on the structure of the lung in rats with pulmonary fibrosis. 展开更多
关键词 Compound Biejia Ruangan prescription rat s pulmonary fibrosis high resolution computerizd tomography
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Generation of high resolution sea surface temperature using multi-satellite data for operational oceanography 被引量:1
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作者 YANG Chan-Su KIM Sun-Hwa +1 位作者 OUCHI Kazuo BACK Ji-Hun 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第7期74-88,共15页
In the present article, we introduce a high resolution sea surface temperature (SST) product generated daily by Korea Institute of Ocean Science and Technology (KIOST). The SST product is comprised of four sets of... In the present article, we introduce a high resolution sea surface temperature (SST) product generated daily by Korea Institute of Ocean Science and Technology (KIOST). The SST product is comprised of four sets of data including eight-hour and daily average SST data of I km resolution, and is based on the four infrared (IR) satellite SST data acquired by advanced very high resolution radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS), Multifunctional Transport Satellites-2 (MTSAT-2) Imager and Meteorological Imager (MI), two microwave radiometer SSTs acquired by Advanced Microwave Scanning Radiometer 2 (AMSR2), and WindSAT with in-situ temperature data. These input satellite and in-situ SST data are merged by using the optimal interpolation (OI) algorithm. The root-mean-square-errors (RMSEs) of satellite and in-situ data are used as a weighting value in the OI algorithm. As a pilot product, four SST data sets were generated daily from Ianuary to December 2013. In the comparison between the SSTs measured by moored buoys and the daily mean KIOST SSTs, the estimated RMSE was 0.71~C and the bias value was -0.08~C. The largest RMSE and bias were 0.86 and -0.26~C respectively, observed at a buoy site in the boundary region of warm and cold waters with increased physical variability in the Sea of Iapan/East Sea. Other site near the coasts shows a lower RMSE value of 0.60~C than those at the open waters. To investigate the spatial distributions of SST, the Group for High Resolution Sea Surface Temperature (GHRSST) product was used in the comparison of temperature gradients, and it was shown that the KIOST SST product represents well the water mass structures around the Korean Peninsula. The KIOST SST product generated from both satellite and buoy data is expected to make substantial contribution to the Korea Operational Oceanographic System (KOOS) as an input parameter for data assimilation. 展开更多
关键词 SST SATELLITE IN-SITU high resolution OI
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A High Resolution Nonhydrostatic Tropical Atmospheric Model and Its Performance 被引量:1
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作者 沈学顺 Akimasa SUMI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期30-38,共9页
A high resolution nonhydrostatic tropical atmospheric model is developed by using a ready-made regional atmospheric modeling system. The motivation is to investigate the convective activities associated with the tropi... A high resolution nonhydrostatic tropical atmospheric model is developed by using a ready-made regional atmospheric modeling system. The motivation is to investigate the convective activities associated with the tropical intraseasonal oscillation (ISO) through a cloud resolving calculation. Due to limitations in computing resources, a 展开更多
关键词 high resolution nonhydrostatic model intraseasonal oscillation MICROPHYSICS CONVECTION
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Determination of Trace Elements in High Purity Gold by High Resolution Inductively Coupled Plasma Mass Spectrometry 被引量:1
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作者 谢华林 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2009年第4期608-612,共5页
Trace elements were determined in high purity gold by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Sample were decomposed by aqua regia. To overcome some potentially problematic spectra/... Trace elements were determined in high purity gold by high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). Sample were decomposed by aqua regia. To overcome some potentially problematic spectra/ interference, measurements were acquired in both medium and high resolution modes. The matrix effects due to the presence of excessive HCl and Au were evaluated. The optimum conditions for the determination was tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits range from 0.01ug/g to 0.28ug/g depending on the elements. The method is accurate, quick and convenient. It has been applied to the determination of trace elements in high purity gold with satisfactory results. 展开更多
关键词 high purity gold trace elements high resolution inductively coupled plasma mass spectrometry spectral interferences
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Retrieval of High Resolution Satellite Images Using Texture Features 被引量:1
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作者 Samia Bouteldja Assia Kourgli 《Journal of Electronic Science and Technology》 CAS 2014年第2期211-215,共5页
In this research, a content-based image retrieval (CBIR) system for high resolution satellite images has been developed by using texture features. The proposed approach uses the local binary pattern (LBP) texture ... In this research, a content-based image retrieval (CBIR) system for high resolution satellite images has been developed by using texture features. The proposed approach uses the local binary pattern (LBP) texture feature and a block based scheme. The query and database images are divided into equally sized blocks, from which LBP histograms are extracted. The block histograms are then compared by using the Chi-square distance. Experimental results show that the LBP representation provides a powerful tool for high resolution satellite images (HRSI) retrieval. 展开更多
关键词 Content-based image retrieval high resolution satellite imagery local binary pattern texture feature extraction
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Three-dimensional time-of-flight magnetic resonance angiography combined with high resolution T2-weighted imaging in preoperative evaluation of microvascular decompression 被引量:1
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作者 Chen Liang Ling Yang +2 位作者 Bin-Bin Zhang Shi-Wen Guo Rui-Chun Li 《World Journal of Clinical Cases》 SCIE 2022年第34期12594-12604,共11页
BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and H... BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD. 展开更多
关键词 Three-dimensional time-of-flight magnetic resonance angiography high resolution T2 weighted imaging Neurovascular compression Microvascular decompression META-ANALYSIS
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A Downsampled SAR-BM3D Despeckling Approach for Single-Look SAR Images in High Resolution 被引量:2
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作者 Wuchao Wang Xiaolin Liu Wenlong Zhang 《Journal of Computer and Communications》 2016年第15期126-131,共7页
SAR-BM3D is one of the state of the art despeckling algorithms for SAR images. However, when tackling with high resolution SAR images, it often has an unsatisfying despeckling performance in the homogeneous smooth reg... SAR-BM3D is one of the state of the art despeckling algorithms for SAR images. However, when tackling with high resolution SAR images, it often has an unsatisfying despeckling performance in the homogeneous smooth regions, together with a high time complexity. In this paper, a novel downsampled SAR-BM3D despeckling approach combined with edge compensation is proposed. The proposed algorithm consists of two steps. First, despeckle the image which is a downsampled version of original image with SAR-BM3D. Then, compensate edges in each level when upsampling. This approach not only utilizes the good ability of feature preservation, but also improves performance of smoothing homogenous regions. When it comes to high resolution SAR images, the efficiency can be raised by six to seven times, compared to original SAR-BM3D. Experiments on simulated and real SAR images show that the proposed method reaches a high level in terms of visual quality and act more efficiently. 展开更多
关键词 Despeckling SAR-BM3D Downsampling high resolution Synthetic Aperture Radar (SAR)
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