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Flexible,high-density,laminated ECoG electrode array for high spatiotemporal resolution foci diagnostic localization of refractory epilepsy 被引量:1
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作者 Yafeng Liu Zhouheng Wang +4 位作者 Yang Jiao Ying Chen Guangyuan Xu Yinji Ma Xue Feng 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第4期388-398,共11页
High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillim... High spatiotemporal resolution brain electrical signals are critical for basic neuroscience research and high-precision focus diagnostic localization,as the spatial scale of some pathologic signals is at the submillimeter or micrometer level.This entails connecting hundreds or thousands of electrode wires on a limited surface.This study reported a class of flexible,ultrathin,highdensity electrocorticogram(ECoG)electrode arrays.The challenge of a large number of wiring arrangements was overcome by a laminated structure design and processing technology improvement.The flexible,ultrathin,high-density ECoG electrode array was conformably attached to the cortex for reliable,high spatial resolution electrophysiologic recordings.The minimum spacing between electrodes was 15μm,comparable to the diameter of a single neuron.Eight hundred electrodes were prepared with an electrode density of 4444 mm^(-2).In focal epilepsy surgery,the flexible,high-density,laminated ECoG electrode array with 36 electrodes was applied to collect epileptic spike waves inrabbits,improving the positioning accuracy of epilepsy lesions from the centimeter to the submillimeter level.The flexible,high-density,laminated ECoG electrode array has potential clinical applications in intractable epilepsy and other neurologic diseases requiring high-precision electroencephalogram acquisition. 展开更多
关键词 Electrocorticogram(ECoG)electrode EPILEPSY High density High resolution Laminated structure
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Advancing ophthalmic delivery of flurbiprofen via synergistic chiral resolution and ion-pairing strategies
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作者 Zhining Ma Yuequan Wang +3 位作者 Huiyang He Tong Liu Qikun Jiang Xiaohong Hou 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第3期177-189,共13页
Flurbiprofen(FB),a nonsteroidal anti-inflammatory drug,is widely employed in treating ocular inflammation owing to its remarkable anti-inflammatory effects.However,the racemic nature of its commercially available form... Flurbiprofen(FB),a nonsteroidal anti-inflammatory drug,is widely employed in treating ocular inflammation owing to its remarkable anti-inflammatory effects.However,the racemic nature of its commercially available formulation(Ocufen^(R))limits the full potential of its therapeutic activity,as the(S)-enantiomer is responsible for the desired antiinflammatory effects.Additionally,the limited corneal permeability of FB significantly restricts its bioavailability.In this study,we successfully separated the chiral isomers of FB to obtain the highly active(S)-FB.Subsequently,utilizing ion-pairing technology,we coupled(S)-FB with various counter-ions,such as sodium,diethylamine,trimethamine(TMA),and l-arginine,to enhance its ocular bioavailability.A comprehensive evaluation encompassed balanced solubility,octanol-water partition coefficient,corneal permeability,ocular pharmacokinetics,tissue distribution,and in vivo ocular anti-inflammatory activity of each chiral isomer salt.Among the various formulations,S-FBTMA exhibited superior water solubility(about 1–12 mg/ml),lipid solubility(1<lgP_(ow)<3)and corneal permeability.In comparison to Ocufen^(R),S-FBTMA demonstrated significantly higher in vivo antiinflammatory activity and lower ocular irritability(such as conjunctival congestion and tingling).The findings from this research highlight the potential of chiral separation and ion-pair enhanced permeation techniques in providing pharmaceutical enterprises focused on drug development with a valuable avenue for improving therapeutic outcomes. 展开更多
关键词 FLURBIPRofEN ANTI-INFLAMMATORY Ophthalmic delivery Chiral resolution ION-PAIRING
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A Unified Model Fusing Region of Interest Detection and Super Resolution for Video Compression
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作者 Xinkun Tang Feng Ouyang +2 位作者 Ying Xu Ligu Zhu Bo Peng 《Computers, Materials & Continua》 SCIE EI 2024年第6期3955-3975,共21页
High-resolution video transmission requires a substantial amount of bandwidth.In this paper,we present a novel video processing methodology that innovatively integrates region of interest(ROI)identification and super-... High-resolution video transmission requires a substantial amount of bandwidth.In this paper,we present a novel video processing methodology that innovatively integrates region of interest(ROI)identification and super-resolution enhancement.Our method commences with the accurate detection of ROIs within video sequences,followed by the application of advanced super-resolution techniques to these areas,thereby preserving visual quality while economizing on data transmission.To validate and benchmark our approach,we have curated a new gaming dataset tailored to evaluate the effectiveness of ROI-based super-resolution in practical applications.The proposed model architecture leverages the transformer network framework,guided by a carefully designed multi-task loss function,which facilitates concurrent learning and execution of both ROI identification and resolution enhancement tasks.This unified deep learning model exhibits remarkable performance in achieving super-resolution on our custom dataset.The implications of this research extend to optimizing low-bitrate video streaming scenarios.By selectively enhancing the resolution of critical regions in videos,our solution enables high-quality video delivery under constrained bandwidth conditions.Empirical results demonstrate a 15%reduction in transmission bandwidth compared to traditional super-resolution based compression methods,without any perceivable decline in visual quality.This work thus contributes to the advancement of video compression and enhancement technologies,offering an effective strategy for improving digital media delivery efficiency and user experience,especially in bandwidth-limited environments.The innovative integration of ROI identification and super-resolution presents promising avenues for future research and development in adaptive and intelligent video communication systems. 展开更多
关键词 Super resolution region of interest detection video compression
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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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Numerical Simulation of Super-Resolution Structured Illumination Microscopy (SIM) Using Heintzmann-Cremer Algorithm with Non-Continuous Spatial Frequency Support
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作者 Mesfin Woldeyohannes William McCray Weiguo Yang 《Optics and Photonics Journal》 2024年第5期75-90,共16页
We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact ... We report a comprehensive numerical study of super resolution (SR) structured illumination microscopy (SIM) utilizing the classic Heintzmann-Cremer SIM process and algorithm. In particular, we investigated the impact of the diffraction limit of the underlying imaging system on the optimal SIM grating frequency that can be used to obtain the highest SR enhancement with non-continuous spatial frequency support. Besides confirming the previous theoretical and experimental work that SR-SIM can achieve an enhancement close to 3 times the diffraction limit with grating pattern illuminations, we also observe and report a series of more subtle effects of SR-SIM with non-continuous spatial frequency support. Our simulations show that when the SIM grating frequency exceeds twice that of the diffraction limit, the higher SIM grating frequency can help achieve a higher SR enhancement for the underlying imaging systems whose diffraction limit is low, though this enhancement is obtained at the cost of losing resolution at some lower resolution targets. Our simulations also show that, for underlying imaging systems with high diffraction limits, however, SR-SIM grating frequencies above twice the diffraction limits tend to bring no significant extra enhancement. Furthermore, we observed that there exists a limit grating frequency above which the SR enhancement effect is lost, and the reconstructed images essentially have the same resolution as the one obtained directly from the underlying imaging system without using the SIM process. 展开更多
关键词 Structured Illumination Microscopy Super resolution Imaging Spatial Frequency Support Diffraction Limit
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Role of Media in Promoting Peace and Conflict Resolution in North Kivu, Democratic Republic of Congo
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作者 Jean-Paul Paluku Kamili Richard Muhindo Taghembwa Jean-Baptiste Kakule Mbakula 《Journalism and Mass Communication》 2024年第2期101-111,共11页
The research examined the role of media in promoting peace and conflict resolution in North Kivu,Democratic Republic of Congo.The security situation in the Democratic Republic of the Congo(DRC),particularly in the eas... The research examined the role of media in promoting peace and conflict resolution in North Kivu,Democratic Republic of Congo.The security situation in the Democratic Republic of the Congo(DRC),particularly in the eastern region of North Kivu,has been deteriorating.The study was anchored in social identity theory.The research methodology employed for this study was qualitative,focusing on the analysis of Mr.Edgar Mateso’s contributions to Radio Okapi’s“Dialogue entre Congolais”program during the period from 2019 to 2023.The research was conducted within the broader context of the persistent war and conflict in the Democratic Republic of Congo,providing valuable insights into the dynamics and challenges of addressing the ongoing insecurity and violence in the region.The study found that media,exemplified by Radio Okapi,plays a multifaceted and significant role in promoting peace and conflict resolution in North Kivu,Democratic Republic of Congo(DRC).It serves as a critical source of accurate information,enabling informed decision-making regarding ceasefire agreements,peace talks,and humanitarian aid.Media fosters dialogue and understanding among different stakeholders,contributing to reconciliation efforts.Additionally,it raises awareness about the human cost of the conflict,challenges misinformation,monitors peace agreements,amplifies the concerns of the affected population,and promotes human rights and justice.Media also engages youth,serves as an early warning system,and attracts global attention to the conflict.It is recommended that media organizations in North Kivu continue their efforts to facilitate dialogue and understanding among different stakeholder groups.Additionally,media should maintain its focus on raising awareness about the human cost of the conflict,ensuring that the suffering of civilians remains in the spotlight and generates international empathy and support.Media outlets should also continue their role as watchdogs by closely monitoring the implementation of ceasefire agreements and reporting any violations transparently.To strengthen media’s role in promoting peace,there should be continued advocacy for peace through dedicated radio programs,news reports,and editorial content.Internationally,media should continue to provide comprehensive coverage of the conflict in North Kivu,attracting global attention and shaping the perception of the conflict on the global stage.Lastly,media organizations should preserve a lasting legacy of peace by archiving peace-related content,documentaries,and narratives of reconciliation. 展开更多
关键词 MEDIA peace building conflict resolution North-Kivu
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High-Resolution Remote Sensing Imagery for the Recognition of Traditional Villages
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作者 Mengchen Wang Linshuhong Shen 《Journal of Architectural Research and Development》 2024年第1期75-83,共9页
Traditional Chinese villages,vital carriers of traditional culture,have faced significant alterations due to urbanization in recent years,urgently necessitating artificial intelligence data updates.This study integrat... Traditional Chinese villages,vital carriers of traditional culture,have faced significant alterations due to urbanization in recent years,urgently necessitating artificial intelligence data updates.This study integrates high spatial resolution remote sensing imagery with deep learning techniques,proposing a novel method for identifying rooftops of traditional Chinese village buildings using high-definition remote sensing images.Using 0.54 m spatial resolution imagery of traditional village areas as the data source,this method analyzes the geometric and spectral image characteristics of village building rooftops.It constructs a deep learning feature sample library tailored to the target types.Employing a semantically enhanced version of the improved Mask R-CNN(Mask Region-based Convolutional Neural Network)for building recognition,the study conducts experiments on localized imagery from different regions.The results demonstrated that the modified Mask R-CNN effectively identifies traditional village building rooftops,achieving an of 0.7520 and an of 0.7400.It improves the current problem of misidentification and missed detection caused by feature heterogeneity.This method offers a viable and effective approach for industrialized data monitoring of traditional villages,contributing to their sustainable development. 展开更多
关键词 Traditional villages Building rooftops High spatial resolution remote sensing Instance segmentation
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Research on Risk Prevention and Resolution Strategies of College Network Ideology in the Context of the Internet
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作者 Feifei Huang 《Journal of Contemporary Educational Research》 2024年第5期85-90,共6页
With the rapid development of the Internet,the network ideology of colleges and universities is facing severe challenges.This paper deeply analyzes the root of the risk of network ideology and makes a specific investi... With the rapid development of the Internet,the network ideology of colleges and universities is facing severe challenges.This paper deeply analyzes the root of the risk of network ideology and makes a specific investigation of the status quo of network public opinion in colleges and universities.On this basis,the study explores and puts forward a series of targeted risk prevention and resolution strategies,aiming at providing a systematic solution for the network ideology security of colleges and universities.In this paper,with the combination of theory and practice as the path,we verify the effectiveness and applicability of the proposed strategy through the analysis of the implementation effect of the strategy.This study also provides theoretical support and practical guidance for the prevention and control of ideological risks and public opinion guidance in universities under the network environment,which has important practical significance.With the continuous progress of network technology,the threats to the network ideology of colleges and universities are increasing.For example,the spread of false information has become a serious problem affecting the security of college network ideology. 展开更多
关键词 Network ideology Colleges and universities Risk prevention Public opinion management resolution strategy Theory and practice
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Error Analysis on Gradient Information of Sloping Land Derived from the Low-resolution DEM 被引量:6
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作者 王莉 贺秀斌 +2 位作者 鲍玉海 南宏伟 刘艳锋 《Agricultural Science & Technology》 CAS 2010年第1期109-112,共4页
With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel rang... With digital elevation model (DEM),sloping data were extracted automatically and soil erosion situation was also investigated. Compared with field survey and the related studies,the results showed that parallel range-gorge landform in Three Gorges reservoir area,the inter-bedded structures formed by Jurassic purple clay (page) rocks and human activities were the key controlling factors for small-scale sloping terrain. 展开更多
关键词 Sloping land resolution of DEM Land use Soil erosion
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REGULARIZATION APPROACH FOR FAST INTEGER AMBIGUITY RESOLUTION OF MEDIUM-LONG BASELINE GPS NETWORK RTK 被引量:4
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作者 罗孝文 欧吉坤 袁运斌 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期235-242,共8页
An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be imp... An improved method based on the Tikhonov regularization principle and the precisely known reference station coordinate is proposed to design the regularized matrix. The ill-conditioning of the normal matrix can be improved by the regularized matrix. The relative floating ambiguity can be computed only by using the data of several epochs. Combined with the LAMBDA method, the new approach can correctly and quickly fix the integer ambiguity and the success rate is 100% in experiments. Through using measured data sets from four mediumlong baselines, the new method can obtain exact ambiguities only by the Ll-frequency data of three epochs. Compared with the existing methods, the improved method can solve the ambiguities of the medium-long baseline GPS network RTK only using L1-frequency GPS data. 展开更多
关键词 GPS network RTK integer ambiguity fast resolution
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Classification of Chinese Traditional Drug-"Beimu" (Bulbus Fritillariae) by Pyrolysis High Resolution Gas Chromatography-Pattern Recognition 被引量:2
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作者 房杏春 李萍 +1 位作者 田琳 安登魁 《Journal of Chinese Pharmaceutical Sciences》 CAS 1992年第2期65-72,共8页
The combination of pyrolysis high resolution gas chromatography and pat- tern recognition techniques is a powerful tool for the classification of traditional Chinese drug.A study has been completed on 55 Beimu samples... The combination of pyrolysis high resolution gas chromatography and pat- tern recognition techniques is a powerful tool for the classification of traditional Chinese drug.A study has been completed on 55 Beimu samples of five different geographic origins: Eastern China.Central China.South-western China,North-western China and North-eastern China.Principal component analysis and SIMCA are applied to effectively classifying the samples according to the origin of the plants.The chemical information contained in the high resolution gas chromatographic data is sufficient to characterize the geographic origin of sam- pies. 展开更多
关键词 Beimu FRITILLARIA Pyrolysis High resolution Gas Chromatography Pattern Recognition
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Effects of Gabor transform parameters on signa time-frequency resolution
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作者 尹陈 贺振华 黄德济 《Applied Geophysics》 SCIE CSCD 2006年第3期169-173,共5页
In this paper, it is described that the time-frequency resolution of geophysical signals is affected by the time window function attenuation coefficient and sampling interval and how such effects are eliminated effect... In this paper, it is described that the time-frequency resolution of geophysical signals is affected by the time window function attenuation coefficient and sampling interval and how such effects are eliminated effectively. Improving the signal resolution is the key to signal time-frequency analysis processing and has wide use in geophysical data processing and extraction of attribute parameters. In this paper, authors research the effects of the attenuation coefficient choice of the Gabor transform window function and sampling interval on signal resolution. Unsuitable parameters not only decrease the signal resolution on the frequency spectrum but also miss the signals. It is essential to first give the optimum window and range of parameters through time-frequency analysis simulation using the Gabor transform. In the paper, the suggestions about the range and choice of the optimum sampling interval and processing methods of general seismic signals are given. 展开更多
关键词 Gabor transform time-frequency analysis resolution Gaussion window sampling interval.
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Perspective of Chinese GF-1 high-resolution satellite data in agricultural remote sensing monitoring 被引量:22
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作者 ZHOU Qing-bo YU Qiang-yi +2 位作者 LIU Jia WU Wen-bin TANG Hua-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期242-251,共10页
High-resolution satellite data have been playing an important role in agricultural remote sensing monitoring. However, the major data sources of high-resolution images are not owned by China. The cost of large scale u... High-resolution satellite data have been playing an important role in agricultural remote sensing monitoring. However, the major data sources of high-resolution images are not owned by China. The cost of large scale use of high resolution imagery data becomes prohibitive. In pace of the launch of the Chinese "High Resolution Earth Observation Systems", China is able to receive superb high-resolution remotely sensed images (GF series) that equalizes or even surpasses foreign similar satellites in respect of spatial resolution, scanning width and revisit period. This paper provides a perspective of using high resolution remote sensing data from satellite GF-1 for agriculture monitoring. It also assesses the applicability of GF-1 data for agricultural monitoring, and identifies potential applications from regional to national scales. GF-1's high resolution (i.e., 2 m/8 m), high revisit cycle (i.e., 4 days), and its visible and near-infrared (VNIR) spectral bands enable a continuous, efficient and effective agricultural dynamics monitoring. Thus, it has gradually substituted the foreign data sources for mapping crop planting areas, monitoring crop growth, estimating crop yield, monitoring natural disasters, and supporting precision and facility agriculture in China agricultural remote sensing monitoring system (CHARMS). However, it is still at the initial stage of GF-1 data application in agricultural remote sensing monitoring. Advanced algorithms for estimating agronomic parameters and soil quality with GF-1 data need to be further investigated, especially for improving the performance of remote sensing monitoring in the fragmented landscapes. In addition, the thematic product series in terms of land cover, crop allocation, crop growth and production are required to be developed in association with other data sources at multiple spatial scales. Despite the advantages, the issues such as low spectrum resolution and image distortion associated with high spatial resolution and wide swath width, might pose challenges for GF-1 data applications and need to be addressed in future agricultural monitoring. 展开更多
关键词 GF-1 high resolution agricultural monitoring remote sensing CHARMS
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The Impact of Horizontal Resolution on the CNOP and on Its Identified Sensitive Areas for Tropical Cyclone Predictions 被引量:16
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作者 ZHOU Feifan MU Mu 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第1期36-46,共11页
In this study, the ilnpacts of horizontal resolution on the conditional nonlinear optimal perturbation (CNOP) and on its identified sensitive areas were investigated for tropical cyclone predictions. Three resolutio... In this study, the ilnpacts of horizontal resolution on the conditional nonlinear optimal perturbation (CNOP) and on its identified sensitive areas were investigated for tropical cyclone predictions. Three resolutions, 30 km, 60 km, and 120 kin, were studied for three tropical cyclones, TC Mindulle (2004), TC Meari (2004), and TC Matsa (2005). Results show that CNOP may present different structures with different resolutions, and the major parts of CNOP become increasingly localized with increased horizontal resolution. CNOP produces spiral and baroclinic structures, which partially account for its rapid amplification. The differences in CNOP structures result in different sensitive areas, but there are common areas for the CNOP-identified sensitive areas at various resolutions, and the size of the common areas is different from case to case. Generally, the forecasts benefit more from the reduction of the initial errors in the sensitive areas identified using higher resolutions than those using lower resolutions. However, the largest improvement of the forecast can be obtained at the resolution that is not the highest for some cases. In addition, the sensitive areas identified at lower resolutions are also helpful for improving the forecast with a finer resolution, but the sensitive areas identified at the same resolution as the forecast would be the most beneficial. 展开更多
关键词 horizontal resolution CNOP sensitive area TC prediction
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Dependence of Hurricane Intensity and Structures on Vertical Resolution and Time-Step Size 被引量:16
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作者 Da-Lin ZHANG and Xiaoxue WANGDepartment of Meteorology, University of Maryland, College Park, Maryland, 20742 USA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2003年第5期711-725,共15页
In view of the growing interests in the explicit modeling of clouds and precipitation, the effects of varying vertical resolution and time-step sizes on the 72-h explicit simulation of Hurricane Andrew (1992) are stud... In view of the growing interests in the explicit modeling of clouds and precipitation, the effects of varying vertical resolution and time-step sizes on the 72-h explicit simulation of Hurricane Andrew (1992) are studied using the Pennsylvania State University/National Center for Atmospheric Research (PSU/NCAR) mesoscale model (i.e., MM5) with the finest grid size of 6 km. It is shown that changing vertical resolution and time-step size has significant effects on hurricane intensity and inner-core cloud/precipitation, but little impact on the hurricane track. In general, increasing vertical resolution tends to produce a deeper storm with lower central pressure and stronger three-dimensional winds, and more precipitation. Similar effects, but to a less extent, occur when the time-step size is reduced. It is found that increasing the low-level vertical resolution is more efficient in intensifying a hurricane, whereas changing the upper-level vertical resolution has little impact on the hurricane intensity. Moreover, the use of a thicker surface layer tends to produce higher maximum surface winds. It is concluded that the use of higher vertical resolution, a thin surface layer, and smaller time-step sizes, along with higher horizontal resolution, is desirable to model more realistically the intensity and inner-core structures and evolution of tropical storms as well as the other convectively driven weather systems. 展开更多
关键词 hurricane intensity vertical resolution numerical weather prediction
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无寄生运动3-DOF 2T1R并联机构拓扑设计与分析
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作者 沈惠平 傅增 +2 位作者 李菊 叶鹏达 李涛 《农业机械学报》 EI CAS CSCD 北大核心 2024年第6期424-433,共10页
为充分研究少自由度并联机构所具备优势,拓宽其应用领域,设计并研究一种含冗余支链且无寄生运动三自由度两平移一转动(2T1R)并联机构,完成运动学和动力学分析。基于方位特征集(POC)的拓扑机构学理论方法,设计了一种含冗余支链且无寄生... 为充分研究少自由度并联机构所具备优势,拓宽其应用领域,设计并研究一种含冗余支链且无寄生运动三自由度两平移一转动(2T1R)并联机构,完成运动学和动力学分析。基于方位特征集(POC)的拓扑机构学理论方法,设计了一种含冗余支链且无寄生运动的两平移一转动并联机构,并进行拓扑分析,结果表明:该机构还具有部分运动解耦特性;根据基于拓扑特征运动学的建模方法,求得机构位置正反符号解;又基于位置反解分析了机构奇异性,基于位置正解给出了工作空间;基于虚功原理的序单开链法对机构进行动力学建模,求得了该机构移动副处的驱动力以及两个子运动链(SKC)连接处的支反力;概念设计了该机构的一种应用场景。 展开更多
关键词 并联机构 方位特征 运动学 奇异性 序单开链 动力学
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SINGULAR INTEGRAL EQUATIONS ALONG AN OPEN ARC WITH SOLUTIONS HAVING SINGULARITIES OF HIGHER ORDER 被引量:5
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作者 钟寿国 《Acta Mathematica Scientia》 SCIE CSCD 2005年第2期193-200,共8页
In this paper, the difficulties on calculation in solving singular integral equations are overcome when the restriction of curve of integration to be a closed contour is cancelled. When the curve is an open arc and th... In this paper, the difficulties on calculation in solving singular integral equations are overcome when the restriction of curve of integration to be a closed contour is cancelled. When the curve is an open arc and the solutions for singular integral equations possess singularities of higher order, the solution and the solvable condition for characteristic equations as well as the generalized Noether theorem for complete equations are given. 展开更多
关键词 Open arc singular integral equation solutions with singularity of higher order Noether theorem characteristic equation
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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:37
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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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Improvement of GPS ambiguity resolution using prior height information. Part Ⅱ: The method of using quasi observation 被引量:12
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作者 朱建军 Rock Santerre 《Journal of Central South University of Technology》 2002年第4期260-266,共7页
This paper deals with the method of using quasi observation. In the paper a simple algorithm is developed for the adjustment computation with quasi observation at first. And then the ability of quasi observation to im... This paper deals with the method of using quasi observation. In the paper a simple algorithm is developed for the adjustment computation with quasi observation at first. And then the ability of quasi observation to improve ambiguity search technique is studied in detail. The robustness of the method is also discussed. A method to determine the weight of quasi observation is proposed. The results show that a prior height can be taken as a quasi observation and used together with GPS observations. It can strengthen residual tests, especially in situation where there are fewer satellites in the sky. It also can change structure of incorrect solutions, which will theoretically make less incorrect solutions left in search space. At last the field tests are carried out to show that the proposed method is effective. The success rate of ambiguity resolution in the four field tests is improved significantly. 展开更多
关键词 ambiquity resolution algorithm with QUASI OBSERVATION ROBUSTNESS
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Simulation study of energy resolution with changing pixel size for radon monitor based on Topmetal-Ⅱ^- TPC 被引量:6
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作者 Meng-Yao Huang Hua Pei +1 位作者 Xiang-Ming Sun Shu-Guang Zou 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第1期49-57,共9页
In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). T... In this paper, we study how pixel size influences energy resolution for a proposed pixelated detector—a high sensitivity, low cost, and real-time radon monitor based on a Topmetal-Ⅱ^- time projection chamber(TPC). This monitor was designed to improve spatial resolution for detecting radon alpha particles using Topmetal-Ⅱ^- sensors assembled by a 0.35 lm CMOS integrated circuit process.Owing to concerns that small pixel size might have the side effect of worsening energy resolution due to lower signalto-noise ratio, a Geant4-based simulation was used to investigate the dependence of energy resolution on pixel sizes ranging from 60 to 600 lm. A non-monotonic trend in this region shows the combined effect of pixel size and threshold on pixels, analyzed by introducing an empirical expression. Pixel noise contributes 50 keV full-width at half-maximum energy resolution for 400 lm pixel size at 1–4σ threshold that is comparable to the energy resolution caused by energy fluctuations in the TPC ionization process( ~20 keV). The total energy resolution after combining both factors is estimated to be 54 keV for a pixel size of 400 lm at 1–4σ threshold. The analysis presented in this paper would help choosing suitable pixel size for future pixelated detectors. 展开更多
关键词 GEANT4 Energy resolution PIXEL size RADON MONITOR Topmetal
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