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Accelerated generation of holograms with ultra-low memory symmetrically high-compressed look-up table
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作者 杨燕 朱建英 +1 位作者 孙敏远 毕勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期466-471,共6页
Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents... Computer-generated holography technology has been widely applied,and as research in this field deepens,the demand for memory and computational power in small AR and VR devices continues to increase.This paper presents a hologram generation method,i.e.,a symmetrically high-compressed look-up table method,which can reduce memory usage by50%.In offline computing,half of the basic horizontal and vertical modulation factors are stored,halving the memory requirements without affecting inline speed.Currently,its potential extends to various holographic applications,including the production of optical diffraction elements. 展开更多
关键词 computergenerated hologram look-up table HOLOGRAPHY
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Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test 被引量:1
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作者 Wu Houli Guo Endong +2 位作者 Wang Jingyi Dai Xin Dai Chenxi 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期163-178,共16页
As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scal... As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much attention.This paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame structure.Different material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic performance.Floor response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical simulation.The acceleration response and displacement response of different combinations are compared.The results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes. 展开更多
关键词 water supply pipe different materials shaking table test amplification factor seismic fragility
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Prevalence of Enteric Pathogens Associated with Infections among Table Egg Consumers in Some Primary Health Establishments in the Center Region of Cameroon
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作者 Mariane Lucie Ngueguim Bernard Viban Tangwa +2 位作者 Victor Ngu Ngwa Albert Ngakou Abdoulmoumini Mamoudou 《Advances in Infectious Diseases》 CAS 2024年第3期606-619,共14页
Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains o... Method: In Cameroon limited data are available regarding the prevalence of enteric bacteria associated with table egg consuming infections. As such, a situational-based study was performed in patients with complains of stomach disorders after egg consumption. Data related to sociodemographic characteristics and other factors were collected using a structured based questionnaire. Stool culture of utmost importance in stomach disorders patients and serum were collected for typhoid serological test. Results: A total of 207 participants took part in the survey, Results indicated nontyphoidal Salmonella infections were highest in the 3 areas of study with Mfoundi (73.44%) having the highest level of infection compared to other bacterial infection. other enteric bacteria associated to this infection were E. coli serotype 157, Aeromonas, Citrobacter freundii, Enterobacter cloaca and typhi salmonella. Meanwhile salmonelosis caused by typhic salmonella had highest prevalence in the Lekie Division (13.11%) as a result of poor hygienic practices associated with the conservation and preparation of eggs, Stool culture was observed to detect more positive cases in the diagnosis of typhoid fever than Widal test, but with no statistically significant (p > 0.05) difference between the stool culture and Widal test in the 3 areas of study. Conclusion: this study revealed that egg consumers are pruned to enteric bacterial and salmonella infections depending on how and where egg is consumed. 展开更多
关键词 Enteric Pathogens table Eggs Consumption Center Region Cameroon
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Effects of water tables and nitrogen application on soil bacterial community diversity, network structure, and function in an alpine wetland, China
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作者 HAN Yaoguang CHEN Kangyi +7 位作者 SHEN Zhibo LI Keyi CHEN Mo HU Yang WANG Jiali JIA Hongtao ZHU Xinping YANG Zailei 《Journal of Arid Land》 SCIE CSCD 2024年第11期1584-1603,共20页
Nitrogen deposition and water tables are important factors to control soil microbial community structure.However,the specific effects and mechanisms of nitrogen deposition and water tables coupling on bacterial divers... Nitrogen deposition and water tables are important factors to control soil microbial community structure.However,the specific effects and mechanisms of nitrogen deposition and water tables coupling on bacterial diversity,abundance,and community structure in arid alpine wetlands remain unclear.The nitrogen deposition(0,10,and 20 kg N/(hm^(2)•a))experiments were conducted in the Bayinbulak alpine wetland with different water tables(perennial flooding,seasonal waterlogging,and perennial drying).The 16S rRNA(ribosomal ribonucleic acid)gene sequencing technology was employed to analyze the changes in bacterial community diversity,network structure,and function in the soil.Results indicated that bacterial diversity was the highest under seasonal waterlogging condition.However,nitrogen deposition only affected the bacterial Chao1 and beta diversity indices under seasonal waterlogging condition.The abundance of bacterial communities under different water tables showed significant differences at the phylum and genus levels.The dominant phylum,Proteobacteria,was sensitive to soil moisture and its abundance decreased with decreasing water tables.Although nitrogen deposition led to changes in bacterial abundance,such changes were small compared with the effects of water tables.Nitrogen deposition with 10 kg N/(hm^(2)•a)decreased bacterial edge number,average path length,and robustness.However,perennial flooding and drying conditions could simply resist environmental changes caused by 20 kg N/(hm^(2)•a)nitrogen deposition and their network structure remain unchanged.The sulfur cycle function was dominant under perennial flooding condition,and carbon and nitrogen cycle functions were dominant under seasonal waterlogging and perennial drying conditions.Nitrogen application increased the potential function of part of nitrogen cycle and decreased the potential function of sulfur cycle in bacterial community.In summary,composition of bacterial community in the arid alpine wetland was determined by water tables,and diversity of bacterial community was inhibited by a lower water table.Effect of nitrogen deposition on bacterial community structure and function depended on water tables. 展开更多
关键词 nitrogen application alpine wetland bacterial community bacterial network water tables
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The Periodic Table of Primes
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作者 Han-Lin Li Shu-Cherng Fang Way Kuo 《Advances in Pure Mathematics》 2024年第5期394-419,共26页
Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers... Over millennia, nobody has been able to predict where prime numbers sprout or how they spread. This study establishes the Periodic Table of Primes (PTP) using four prime numbers 2, 3, 5, and 7. We identify 48 integers out of a period 2×3×5×7=210 to be the roots of all primes as well as composites without factors of 2, 3, 5, and 7. Each prime, twin primes, or composite without factors of 2, 3, 5, and 7 is an offspring of the 48 integers uniquely allocated on the PTP. Three major establishments made in the article are the Formula of Primes, the Periodic Table of Primes, and the Counting Functions of Primes and Twin Primes. 展开更多
关键词 PRIMES COMPOSITES the Periodic table of Primes
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Opinions of Students on the Contribution of the DIVA 3D Virtual Dissection Table to the Teaching of Anatomy at the Faculty of Medicine and Odontostomatology of Bamako
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作者 Abdoulaye Kanté Tata Touré +8 位作者 Ousmane Toumany Chérif Haidara Uhl Jean François Mariam Daou Mamadou A. Keita Bakary Keïta Bréhima Bengaly Drissa Traoré Adégné Togo Nouhoum Ongoïba 《Forensic Medicine and Anatomy Research》 2024年第2期13-25,共13页
Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from Nov... Objective: Study the contribution of the DIVA 3D dissection table in the teaching of anatomy at the Faculty of Medicine and Odontology of Bamako. Material and Methods: This was a qualitative study carried out from November 1 to December 30, 2023 at the clinical and morphological anatomy laboratory of the Faculty of Medicine and Odontostomatology of Bamako. Included in this study were students who participated in practical and tutorial sessions. The variables studied during this study were: the previous performance of dissection on a cadaver by the students, the opinion of the students on dissection on a cadaver, the replacement of dissection on a cadaver by virtual dissection in the absence of a body, the level student satisfaction. Results: We surveyed 130 participants. The average age was 22 ± 0.2 years with extremes of 17 and 29 years. 95.3% of participants were students. According to 66.7% of participants, virtual dissection is a good palliative in the absence of a corpse. 95.3% of participants found using the virtual dissection table easy with an average of 7.88 ± 1.4. The overall assessment was well rated by 99.3% of participants. Conclusion: According to the results of this study, the virtual dissection table should be improved by integrating commented videos. The use of the DIVA 3D virtual dissection table during practical and tutorial sessions is well appreciated by the students. We believe that the teaching of anatomy using 3D digital technology should be included in the study programs of the Faculty of Medicine and Odontostomatology. 展开更多
关键词 Student Opinion CONTRIBUTION DIVA 3D Virtual Dissection table Anatomy Teaching FMOS
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Improving Video Watermarking through Galois Field GF(2^(4)) Multiplication Tables with Diverse Irreducible Polynomials and Adaptive Techniques
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作者 Yasmin Alaa Hassan Abdul Monem S.Rahma 《Computers, Materials & Continua》 SCIE EI 2024年第1期1423-1442,共20页
Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4))... Video watermarking plays a crucial role in protecting intellectual property rights and ensuring content authenticity.This study delves into the integration of Galois Field(GF)multiplication tables,especially GF(2^(4)),and their interaction with distinct irreducible polynomials.The primary aim is to enhance watermarking techniques for achieving imperceptibility,robustness,and efficient execution time.The research employs scene selection and adaptive thresholding techniques to streamline the watermarking process.Scene selection is used strategically to embed watermarks in the most vital frames of the video,while adaptive thresholding methods ensure that the watermarking process adheres to imperceptibility criteria,maintaining the video's visual quality.Concurrently,careful consideration is given to execution time,crucial in real-world scenarios,to balance efficiency and efficacy.The Peak Signal-to-Noise Ratio(PSNR)serves as a pivotal metric to gauge the watermark's imperceptibility and video quality.The study explores various irreducible polynomials,navigating the trade-offs between computational efficiency and watermark imperceptibility.In parallel,the study pays careful attention to the execution time,a paramount consideration in real-world scenarios,to strike a balance between efficiency and efficacy.This comprehensive analysis provides valuable insights into the interplay of GF multiplication tables,diverse irreducible polynomials,scene selection,adaptive thresholding,imperceptibility,and execution time.The evaluation of the proposed algorithm's robustness was conducted using PSNR and NC metrics,and it was subjected to assessment under the impact of five distinct attack scenarios.These findings contribute to the development of watermarking strategies that balance imperceptibility,robustness,and processing efficiency,enhancing the field's practicality and effectiveness. 展开更多
关键词 Video watermarking galois field irreducible polynomial multiplication table scene selection adaptive thresholding
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Evaluation of the effects of EPS composite soil replacement on the dynamic performance of caisson structure using shaking table tests
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作者 Gao Hongmei Ji Zhanpeng +3 位作者 Zhang Xinlei Zhang Shushan Wang Zhihua Shen Guangming 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期829-843,共15页
The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The ma... The seismic performance of a caisson structure under two types of models with a saturated sandy foundation(CSS)and an expanded polystyrene(EPS)composite soil foundation(CES)are studied using shaking table tests.The macro phenomena of the two different foundation models are described and analyzed.The effects of the replacement of EPS composite soil on seismic-induced liquefaction of backfill and the dynamic performance of a caisson structure are evaluated in detail.The results show that the excess pore water pressure generation in the CES is significantly slower than that in the CSS during the shaking.The dynamic earth pressure acting on the caisson has a triangular shape.The response of horizontal acceleration,displacement,settlement,and rotation angle of the caisson in the CES is smaller than that in the CSS,which means the caisson in the CES has a better seismic performance.Furthermore,the out-of-phase phenomenon between dynamic earth thrust and inertial force in the CES is more obvious than that in the CSS,which is beneficial to reduce the lateral force and improve the stability of the caisson structure. 展开更多
关键词 EPS composite soil foundation Caisson-type quay wall shaking table test phase difference rotation angle
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Numerical analysis on seismic performance of underground structures in liquefiable interlayer sites from centrifuge shaking table test
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作者 Yan Guanyu Xu Chengshun +2 位作者 Zhang Zihong Du Xiuli Wang Xuelai 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第4期781-798,共18页
When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response... When an underground structure passes through a liquefiable soil layer,the soil liquefaction may pose a significant threat to the structure.A centrifuge shaking table test was performed to research the seismic response of underground structures in liquefiable interlayer sites,and a valid numerical model was obtained through simulation model test.Finally,the calibrated numerical model was used to perform further research on the influence of various distribution characteristics of liquefiable interlayers on the seismic reaction of underground structures.The key findings are as follows.The structure faces the most unfavorable condition once a liquefiable layer is located in the middle of the underground structure.When a liquefiable layer exists in the middle of the structure,the seismic reactions of both the underground structure and model site will increase with the rise of the thickness of the liquefiable interlayer.The inter-story drift of the structure in the non-liquefiable site is much smaller than that in the liquefiable interlayer site.The inter-story drift of the structure is not only associated with the site displacement and the soil-structure stiffness ratio but also closely associated with the slippage of the soil-structure contact interface under the condition of large deformation of the site. 展开更多
关键词 centrifuge shaking table test underground structure liquefiable interlayer sites seismic response validation of numerical model
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A novel control strategy for reproducing the floor motions of high-rise buildings by earthquake-simulating shake tables
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作者 Yuteng Cao Zhe Qu Xiaodong Ji 《Earthquake Research Advances》 CSCD 2024年第1期67-75,共9页
To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Tab... To enable the experimental assessment of the seismic performance of full-scale nonstructural elements with multiple engineering parameters(EDPs),a three-layer testbed named Nonstructural Element Simulator on Shake Table(NEST)has been developed.The testbed consists of three consecutive floors of steel structure.The bottom two floors provide a space to accommodate a full-scale room.To fully explore the flexibility of NEST,we propose a novel control strategy to generate the required shake table input time histories for the testbed to track the target floor motions of the buildings of interest with high accuracy.The control strategy contains two parts:an inverse dynamic compensation via simulation of feedback control systems(IDCS)algorithm and an offline iteration procedure based on a refined nonlinear numerical model of the testbed.The key aspects of the control strategy were introduced in this paper.Experimental tests were conducted to simulate the seismic responses of a full-scale office room on the 21^(st)floor of a 42-story high-rise building.The test results show that the proposed control strategy can reproduce the target floor motions of the building of interest with less than 20%errors within the specified frequency range. 展开更多
关键词 Shake table test Nonstructural element High-rise building Open-loop IDCS algorithm Off-line iteration
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Pre-training transformer with dual-branch context content module for table detection in document images
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作者 Yongzhi LI Pengle ZHANG +2 位作者 Meng SUN Jin HUANG Ruhan HE 《虚拟现实与智能硬件(中英文)》 EI 2024年第5期408-420,共13页
Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such... Background Document images such as statistical reports and scientific journals are widely used in information technology.Accurate detection of table areas in document images is an essential prerequisite for tasks such as information extraction.However,because of the diversity in the shapes and sizes of tables,existing table detection methods adapted from general object detection algorithms,have not yet achieved satisfactory results.Incorrect detection results might lead to the loss of critical information.Methods Therefore,we propose a novel end-to-end trainable deep network combined with a self-supervised pretraining transformer for feature extraction to minimize incorrect detections.To better deal with table areas of different shapes and sizes,we added a dualbranch context content attention module(DCCAM)to high-dimensional features to extract context content information,thereby enhancing the network's ability to learn shape features.For feature fusion at different scales,we replaced the original 3×3 convolution with a multilayer residual module,which contains enhanced gradient flow information to improve the feature representation and extraction capability.Results We evaluated our method on public document datasets and compared it with previous methods,which achieved state-of-the-art results in terms of evaluation metrics such as recall and F1-score.https://github.com/Yong Z-Lee/TD-DCCAM. 展开更多
关键词 table detection Document image analysis TRANSFORMER Dilated convolution Deformable convolution Feature fusion
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Impact of water table on hierarchically nested groundwater flow system
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作者 Jun Zhang Rong-zhe Hou +2 位作者 Kun Yu Jia-qiu Dong Li-he Yin 《Journal of Groundwater Science and Engineering》 2024年第2期119-131,共13页
Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flo... Water table configuration gives rise to hierarchically nested groundwater flow systems.However,there remains a lack of comprehensive understanding regarding the controlling factors of water table and its impact on flow systems.Moreover,it remains challenging to identify characteristics of water table space variation through limited groundwater observations at the regional scale.Based on two ideal two-dimensional cross-section analytical models,this study presents a simplified approach to preliminarily assess the nonlinear interactions between water table variation and three driving factors:Topography,geol-ogy and climate.Two criteria,C1 and C2,are utilized to address issues at different scales ranging from basin to local:(i)the influence of various factors on water table configuration;and(ii)the influence of water table on groundwater flow pattern.Then,the Ordos Plateau is taken as an example to explore the role of the water table in nested groundwater systems using the provided approach and criterion.The applica-tion of this approach in the Ordos Plateau demonstrates its appropriateness as a practical method for prelim-inarily determining the characteristics of water table configuration and its impact on flow systems.The study explores the mechanism influencing spatial variation in the water table and improves understanding of the interaction between topography,geology,and climate on groundwater flow patterns. 展开更多
关键词 Water table configuration Groundwater flow pattern Analytical models Top boundary condi-tions Ordos Plateau
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Fine Doppler shift acquisition algorithm for BeiDou software receiver by a look-up table 被引量:3
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作者 QIU Wenqi ZENG Qingxi +1 位作者 GAO Chang LYU Chade 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第3期612-625,共14页
The BeiDou software receiver uses the fast Fourier transform(FFT)to perform the acquisition.The Doppler shift estimation accuracy should be less than 500 Hz to ensure satellite signals to enter a locked state in the t... The BeiDou software receiver uses the fast Fourier transform(FFT)to perform the acquisition.The Doppler shift estimation accuracy should be less than 500 Hz to ensure satellite signals to enter a locked state in the tracking loop.Since the frequency step is usually 500 Hz or larger,the Doppler shift estimation accuracy cannot guarantee that satellite signals are brought into a stable tracking state.The straightforward solutions consist in increasing the sampling time and using zero-padding to improve the frequency resolution of the FFT.However,these solutions intensify the complexity and amount of computation.The contradiction between the acquisition accuracy and the computational load leads us to research for a more simple and effective algorithm,which achieves fine acquisition by a look-up table.After coarse acquisition using the parallel frequency acquisition(PFA)algorithm,the proposed algorithm optimizes the Doppler shift estimation through the look-up table method based on the FFT results to improve the acquisition accuracy of the Doppler shift with a minimal additional computing load.When the Doppler shift is within the queryable range of the table,the proposed algorithm can improve the Doppler shift estimation accuracy to 50 Hz for the BeiDou B1I signal. 展开更多
关键词 fine acquisition fast Fourier transform(FFT) table look-up parallel frequency acquisition(PFA) BEIDOU
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Accurate and fast table look-up models for leakage current analysis in 65nm CMOS technology
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作者 薛冀颖 李涛 余志平 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2009年第2期42-47,共6页
Novel physical models for leakage current analysis in 65 nm technology are proposed. Taking into consideration the process variations and emerging effects in nano-scaled technology, the presented models are capable of... Novel physical models for leakage current analysis in 65 nm technology are proposed. Taking into consideration the process variations and emerging effects in nano-scaled technology, the presented models are capable of accurately estimating the subthreshold leakage current and junction tunneling leakage current in 65 nm technology. Based on the physical models, new table look-up models are developed and first applied to leakage current analysis in pursuit of higher simulation speed. Simulation results show that the novel physical models are in excellent agreement with the data measured from the foundry in the 65 nm process, and the proposed table look-up models can provide great computational efficiency by using suitable interpolation techniques. Compared with the traditional physical-based models, the table look-up models can achieve 2.5X speedup on average on a variety of industry circuits. 展开更多
关键词 leakage current 65 nm technology table look-up model INTERPOLATION
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A general purpose exact Rayleigh scattering look-up table for ocean color remote sensing 被引量:5
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作者 HE Xianqiang PAN Delu +1 位作者 BAI Yan GONG Fang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期48-56,共9页
The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table (LUT), which is usually created for a special remote sensor and cannot be applied to other sensors. For practica... The current exact Rayleigh scattering calculation of ocean color remote sensing uses the look-up table (LUT), which is usually created for a special remote sensor and cannot be applied to other sensors. For practical application, a general purpose Rayleigh scattering LUT which can be applied to all ocean color remote sensors is generated. An adding-doubling method to solve the vector radiative transfer equation in the plane-parallel atmosphere is deduced in detail. Compared with the exact Rayleigh scattering radiance derived from the MODIS exact Rayleigh scattering LUT, it is proved that the relative error of Rayleigh scattering calculation with the adding-doubling method is less than 0.25%, which meets the required accuracy of the atmospheric correction of ocean color remote sensing. Therefore, the adding-doubling method can be used to generate the exact Rayleigh scattering LUT for the ocean color remote sensors. Finally, the general purpose exact Rayleigh scattering LUT is generated using the adding-doubling method. On the basis of the general purpose LUT, the calculated Rayleigh scattering radiance is tested by comparing with the LUTs ofMODIS, SeaWiFS and the other ocean color sensors, showing that the relative errors are all less than 0.5%, and this general purpose LUT can be applied to all ocean color remote sensors. 展开更多
关键词 ocean color Rayleigh scattering look-up table radiative transfer adding-doubling method
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Performance of global look-up table strategy in digital image correlation with cubic B-spline interpolation and bicubic interpolation 被引量:4
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作者 Zhiwei Pan Wei Chen +3 位作者 Zhenyu Jiang Liqun Tang Yiping Liu Zejia Liu 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2016年第3期126-130,共5页
Global look-up table strategy proposed recently has been proven to be an efficient method to accelerate the interpolation, which is the most time-consuming part in the iterative sub-pixel digital image correlation (... Global look-up table strategy proposed recently has been proven to be an efficient method to accelerate the interpolation, which is the most time-consuming part in the iterative sub-pixel digital image correlation (DIC) algorithms. In this paper, a global look-up table strategy with cubic B-spline interpolation is developed for the DIC method based on the inverse compositional Gauss-Newton (IC-GN) algorithm. The performance of this strategy, including accuracy, precision, and computation efficiency, is evaluated through a theoretical and experimental study, using the one with widely employed bicubic interpolation as a benchmark. The global look-up table strategy with cubic B-spline interpolation improves significantly the accuracy of the IC-GN algorithm-based DIC method compared with the one using the bicubic interpolation, at a trivial price of computation efficiency. 展开更多
关键词 Digital image correlation Inverse compositional Gauss-Newton algorithm Cubic B-spline interpolation Bicubic interpolation Global look-up table
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Determination method of permafrost table in seasonal frozen soil areas under“Water-Heat-Salt”coupling
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作者 WANG Fang YANG Zhong +1 位作者 LIU Kai LU Chang-long 《Journal of Mountain Science》 SCIE CSCD 2023年第11期3266-3282,共17页
The permafrost table is an important index for the design and construction of roads in cold regions,so it is necessary to find a convenient,accurate and fast judgment method to determine the permafrost table.In this s... The permafrost table is an important index for the design and construction of roads in cold regions,so it is necessary to find a convenient,accurate and fast judgment method to determine the permafrost table.In this study,a three-field coupled model was established based on the hydrothermal salt coupling within the permafrost and the similarity theory,and the changes of the permafrost table under different temperature,moisture and salt conditions were numerically simulated by considering the transient temperature change and the influence of the permafrost layer on the seasonally thawed layer.In addition,an accelerated permafrost table test method was designed based on the time-domain variation and hydrothermal salt coupling by the similarity theory,which rapidly simulated the permafrost table change under different temperatures,moisture,and salts in the natural environment.Comparing the simulation and test results with the measured values in the field,the errors are less than 3%,which verified the feasibility of the method for determining the permafrost table,and the simulated results are better than the test results.Results show that the results of determining the permafrost table with a single index have different degrees of deviation,and the permafrost table obtained by the temperature index is the most accurate in general,and it is more accurate to use the average value of the three indexes as the permafrost table compared with a single index. 展开更多
关键词 Permafrost table Hydrothermal salt coupling Seasonally thawed layer Numerical simulation Accelerated test
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Research of NO_(2) vertical profiles with look-up table method based on MAX-DOAS
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作者 Yingying Guo Suwen Li +2 位作者 Fusheng Mou Hexiang Qi Qijin Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期332-338,共7页
Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution.In this article,a look-up table method based on multi-axis differential optical a... Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution.In this article,a look-up table method based on multi-axis differential optical absorption spectroscopy(MAX-DOAS)technology is established for retrieving the tropospheric NO_(2) vertical distribution profiles.This method retrieves the aerosol extinction profiles with minimum cost function.Then,the aerosol extinction profiles and the atmospheric radiation transfer model(RTM)are employed to establish the look-up table for retrieving the NO_(2) vertical column densities(VCDs)and profiles.The measured NO_(2) differential slant column densities(DSCDs)are compared with the NO_(2) DSCDs simulated by the atmospheric RTM,and the NO_(2) VCDs,the weight factor of NO_(2) in the boundary layer,and the boundary layer height are obtained by the minimization process.The look-up table is established to retrieve NO_(2) VCDs based on MAX-DOAS measurements in Huaibei area,and the results are compared with the data from Copernicus Atmospheric Monitoring Service(CAMS)model.It is found that there are nearly consistent and the correlation coefficient R2 is more than 0.86.The results show that this technology provides a more convenient and accurate retrieval method for the stereoscopic monitoring of atmospheric environment. 展开更多
关键词 multi-axis differential optical absorption spectroscopy look-up table method the cost function NO_(2)vertical profile
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WinoNet:Reconfigurable look-up table-based Winograd accelerator for arbitrary precision convolutional neural network inference
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作者 Wang Chengcheng Li He +3 位作者 Cao Yanpeng Song Changjun Yu Feng Tang Yongming 《Journal of Southeast University(English Edition)》 EI CAS 2022年第4期332-339,共8页
To solve the hardware deployment problem caused by the vast demanding computational complexity of convolutional layers and limited hardware resources for the hardware network inference,a look-up table(LUT)-based convo... To solve the hardware deployment problem caused by the vast demanding computational complexity of convolutional layers and limited hardware resources for the hardware network inference,a look-up table(LUT)-based convolution architecture built on a field-programmable gate array using integer multipliers and addition trees is used.With the help of the Winograd algorithm,the optimization of convolution and multiplication is realized to reduce the computational complexity.The LUT-based operator is further optimized to construct a processing unit(PE).Simultaneously optimized storage streams improve memory access efficiency and solve bandwidth constraints.The data toggle rate is reduced to optimize power consumption.The experimental results show that the use of the Winograd algorithm to build basic processing units can significantly reduce the number of multipliers and achieve hardware deployment acceleration,while the time-division multiplexing of processing units improves resource utilization.Under this experimental condition,compared with the traditional convolution method,the architecture optimizes computing resources by 2.25 times and improves the peak throughput by 19.3 times.The LUT-based Winograd accelerator can effectively solve the deployment problem caused by limited hardware resources. 展开更多
关键词 quantized neural networks look-up table(LUT)-based multiplier Winograd algorithm arbitrary precision
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Seasonal Effect on Weather Elements on Water Table Fluctuation in Potable Wells in Kono District, Eastern Sierra Leone
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作者 Richard Tamba Simbo Alhaji Brima Gogra +1 位作者 Yahaya Kudus Kawa Paul Juana Moiwo 《Open Journal of Applied Sciences》 2023年第11期2198-2209,共12页
The study investigated the seasonal effects of weather elements on water table fluctuations in drinking wells in Nimikoro and Tankoro Chiefdoms in Kono District, Eastern Sierra Leone. The study specifically determined... The study investigated the seasonal effects of weather elements on water table fluctuations in drinking wells in Nimikoro and Tankoro Chiefdoms in Kono District, Eastern Sierra Leone. The study specifically determined the trends in precipitation, air temperature and relative humidity relative to water table depth and water volume in both manually dug and mechanically drilled water wells in the chiefdoms. The key objective was to provide a clear guide on sustainable well development and operation in the study area and beyond. To do so, the depth of each well was taken and the water table measured. Also, data on key weather elements such as precipitation, air temperature and relative humidity were collected on the 15<sup>th</sup> of every month for a period of one year. The data were analyzed on Excel, SPSS and ArcGIS platforms for monthly and seasonal trends in the time-space fabric. The results showed that the depth to water table was high in the dries (small well water volume) and low in the rains (large well water volume) for both manually dug and mechanically drilled wells. Well water temperature increased as temperature increased during the dry season but decreased as temperature decreased during the rainy season. The study showed that weather elements such as precipitation and temperature had direct impact on groundwater availability. This is critical for groundwater development and management in the study area and in Sierra Leone at large. 展开更多
关键词 GROUNDWATER Water table Relative Humidity PRECIPITATION Temperature
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