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Application of deep learning technique to the sea surface height prediction in the South China Sea

Acta Oceanologica Sinica 2021年第7期40卷 68-76页

作者： Tao Song ningsheng Han Yuhang Zhu Zhongwei Li Yineng Li Shaotian Li Shiqiu Peng College of Computer and Communication Engineering China University of Petroleum(East China)Qingdao 266580China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Science and Technology on Operational Oceanography Chinese Academy of SciencesGuangzhou 511458China Guangxi Key Laboratory of Marine Disaster in the Beibu Gulf Bubei Gulf UniversityQinzhou 535011China Department of Artificial Intelligence Faculty of Computer SciencePolytechnical University of MadridBoadilla del Monte 28660MadridSpain

A deep-learning-based method,called ConvLSTMP3,is developed to predict the sea surface heights(SSHs).ConvLSTMP3 is data-driven by treating the SSH prediction problem as the one of extracting the spatial-temporal features of SSHs,in which the spatial features are“learned”by convolutional operations while the temporal features are tracked by long short term memory(LSTM).Trained by a reanalysis dataset of the South China Sea(SCS),ConvLSTMP3 is applied to the SSH prediction in a region of the SCS east off Vietnam coast featured with eddied and offshore currents in *** results show that ConvLSTMP3 achieves a good prediction skill with a mean RMSE of 0.057 m and accuracy of 93.4%averaged over a 15-d prediction *** particular,ConvLSTMP3 shows a better performance in predicting the temporal evolution of mesoscale eddies in the region than a full-dynamics ocean *** the much less computation in the prediction required by ConvLSTMP3,our study suggests that the deep learning technique is very useful and effective in the SSH prediction,and could be an alternative way in the operational prediction for ocean environments in the future.

关键词： deep learning sea surface height prediction convolutional operation long short term memory

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Big Disaster from Small Watershed:Insights into the Failure and Disaster‑Causing Mechanism of a Debris Flow on 25 September 2021 in Tianquan,China

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International Journal of Disaster Risk Science 2024年第4期15卷 622-639页

作者： Runing Hou Mingyang Wu Zhi Li ningsheng Chen Xiaohu Chen Taixin Peng Na Huang Key Laboratory of Mountain Hazards and Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China School of Geosciences Yangtze UniversityWuhan 430100China Academy of Plateau Science and Sustainability Xining 810016China University of Chinese Academy of Sciences Beijing 100049China

The occurrence of debris flow events in small-scale watersheds with dense vegetation in mountainous areas that result in significant loss of life and missing individuals challenges our understanding and expertise in investigating and preventing these disasters. This has raised concerns about the occurrence of large debris flow disasters from small watersheds. This study focused on a catastrophic debris flow that took place in Longtou Gully(0.45 km^(2)) in Tianquan County, Ya'an City on 25 September 2021, which resulted in 14 deaths and missing individuals. Through comprehensive field investigations, highprecision remote sensing data analyses, and numerical simulations, we analyzed the triggering mechanisms and dynamic processes of this event. Our results indicate that the convergence hollow at the channel head exhibited higher hydraulic conditions during rainfall compared to gentle slopes and convex terrains, leading to the instability of colluvial soil due to the expansion of the saturated zone near the soil–bedrock interface. The entrainment of material eroded from the channel resulted in an approximately 4.7 times increase in volume, and the channel scarp with a height of about 200 m amplified the destructive power of the debris flow. We emphasize the need to take seriously the possibility of catastrophic debris flows in small-scale watersheds, with colluvial deposits in hollows at the channel head under vegetation cover that serve as precursor material sources, and the presence of channel scarps formed by changes in the incision rate of the main river, which is common in the small watershed on both sides. This study provides insights for risk assessment of debris flows in small-scale catchments with dense vegetation cover in mountainous areas, highlighting the importance of vigilance in addressing disasters in small-scale catchments, particularly in regions with increasing human–environment conflicts.

关键词： China Colluvial soil Low-frequency debris fows Risk reduction Topographic hollows

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Optimized selection of suitable sites for farmland consolidation projects using multi-objective genetic algorithms

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International Journal of Agricultural and Biological Engineering 2014年第3期7卷 19-27页

作者： Wang Lu Huang ningsheng Kuang Yaoqiu Zhou Jinhao Zhao Yuan Zhang Zhen Hu Yueming Guangzhou Institute of Geochemistry Chinese Academic of ScienceGuangzhou 510640Guangdong ProvinceChina University of Chinese Academic of Sciences Beijing 100039China College of Information South China Agricultural UniversityGuangzhou 510642Guangdong ProvinceChina Guangdong Province Land Use and Remediation of the Key Laboratory Guangzhou 510642Guangdong ProvinceChina

In order to select suitable sites for farmland consolidation projects,correlation analysis and evolutionary algorithms were used to optimize the evaluation of ecological,social and economic factors,avoiding subjective selection and ignorance of spatial relationships among land ***-objective Genetic Algorithms(MOGA)were applied to select the best sites from the perspective of spatial relationship and land attribute *** carefully defined restrictions and variables,multi-objective optimization is able to select several suitable sites for farmland consolidation *** results from a case study in Yangshan,Guangdong of China showed that the selected sites were on the central and southern Yangshan with expected flat terrain and abundant water *** empirical experiment also demonstrated that the proposed method is able to provide well selected sites for land consolidation projects.

关键词： farmland consolidation site selection evaluation index system multi-objective optimization genetic algorithm suitability

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播期对不同熟期马铃薯生育期及产量的影响

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作物研究 2018年第3期32卷 198-201页

作者：张磊徐宁生潘哲超杨琼芬李燕山包丽仙白建明李先平隋启君云南省农业科学院经济作物研究所/农业部云贵高原马铃薯与油菜科学观测实验站昆明650205

试验以3个不同成熟期类型马铃薯品种为供试材料,设4个播期处理,研究云南秋作区播期对不同熟期马铃薯品种的生育期、产量、产量构成及总产值的影响,为不同品种的合理播期提供依据。结果表明:‘云薯505’适宜播期为7月中旬,‘丽薯6号’为... 详细信息

试验以3个不同成熟期类型马铃薯品种为供试材料,设4个播期处理,研究云南秋作区播期对不同熟期马铃薯品种的生育期、产量、产量构成及总产值的影响,为不同品种的合理播期提供依据。结果表明:‘云薯505’适宜播期为7月中旬,‘丽薯6号’为7月中旬到8月上旬,‘云薯401’为7月中旬到8月初。如以追求产值最大化为目的,3个品种均建议尽早播种。

关键词：马铃薯播种期生育期产量

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May-June mean maximum temperature change during 1360-2005 as reconstructed by tree rings of Sabina Tibetica in Zaduo,Qinghai Province

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Chinese Science Bulletin 2010年第26期55卷 3023-3029页

作者： SHI XingHe QIN ningsheng ZHU HaiFeng SHAO xueMei WANG QingChun ZHU XiDe Institute of Plateau Meteorology China Meteorological Administration Chengdu 610072 China Climate Date Center ofQinghai Qinghai Meteorological Bureau Xining 810001 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Based on tree-ring samples collected from Zaduo area in southern Qinghai Province, a 646-year ring-width series was established. Using response function, correlation function and partial correlation analysis we found that the ring-width series is sensitive most to May and June mean maximum air temperature at Zaduo meteorological stations and the correlation is significantly negative. Therefore, May-June mean maximum air temperature in Zaduo area since 1360 is reconstructed using this ring-width series. The regression equation was cross-validated in the calibration period of 1961-2005. The calibration equation can explain 59.8% of the total variance. Since high temperature could reinforce evapotranspiration and result in water stress, the high values are more reliable than the low values in the reconstructed series. By further analyzing upon the reconstructed series, it shows that on the in-ter-annual scale there are 6 periods with higher temperature: 1438-1455, 1572-1612, 1684-1700, 1730-1754, 1812-1829 and 1853-1886; while there are 5 periods with lower temperature: 1547-1571, 1701-1729, 1755-1777, 1830-1852 and 1887-1910. There is no significant rising of temperature in recent 50 years. By comparison with the rings-width series nearby which are also sensitive to the mean maximum air temperature and the mean maximum temperature reconstruction by ring-widths, it is found that the variation of inter-annual scale is fairly common in the region.

关键词：树木年轮三江源自然保护区温度变化月平均青海省平均最高气温年轮宽度年际尺度

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Role of in-situ Formed Nonoxides Bonded Phases in Property Improvement of Alumina ULC Castables

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China's Refractories 2013年第1期22卷 17-20页

作者： YU Renhong DU Penghui ZHOU ningsheng LI Cuixia High Temperature Materials Institute Henan University of Science and Technology Sinosteel Refractory Co. Ltd

In order to enhance performance of pre-cast shapes of alumina based castables, the present work explored the approach of forming in-situ bonding phases by incorporating Si powders and then heating in carbon, embedded atmosphere. Using tabular alumina as aggregates, tabular alumina, SiC powders, Si powders, calcium aluminate cenwnt, microsilica and ultrafine α-A12 03 powders as matrix, alumina based ultra low cement （ULC） castables were prepared. Influences of Si powder addition at O, 4% , 6% , 8% alul 10% （in nutss ） on regular properties, cold modulus of rupture （CMOR）, hot modulus of rupture （HMOR）, thermal shock resistance （TSR） and microstructure of the castables after carbonization were investigated. After incorporation of Si powders and carbon embedded heating, the in-situ mullite and nonoxide phases such as SiAION and SiC can be fornwd by oxidation, nitridation or carbomlzation reaction. HMOR and TSR of the castables with in-situ nonoxides bonding are obviously improted. After carbon embedded heating, the HMOR at 1 400 ℃ increases from 1.6 MPa to 8. 3 MPa, and the residual CMOR ratio after thermal shock increases from 64. 9% to 137. 9% when Si addition increases from 0 to 10%.

关键词： alumina based castables silicon powder carbon embedding carbonization nonoxide

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CO2 residual concentration of potassium-promoted hydrotalcite for deep CO/CO2 purification in H2-rich gas

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Journal of Energy Chemistry 2017年第5期26卷 956-964页

作者： xuancan Zhu Yixiang Shi ningsheng Cai Key Laboratory for Thermal Science and Power Engineer of Ministry of Education Department of Thermal EngineeringTsinghua UniversityBeijing 100084China

Elevated-temperature pressure swing adsorption is a promising technique for producing high purity hydrogen and controlling greenhouse gas emissions. Thermodynamic analysis indicated that the CO in H-rich gas could be controlled to trace levels of below 10 ppm by in situ reduction of the COconcentration to less than 100 ppm via the aforementioned process. The COadsorption capacity of potassiumpromoted hydrotalcite at elevated temperatures under different adsorption（mole fraction, working pressure） and desorption（flow rate, desorption time, steam effects） conditions was systematically investigated using a fixed bed reactor. It was found that the COresidual concentration before the breakthrough of COmainly depended on the total amount of purge gas and the COmole fraction in the inlet *** residual COconcentration and uptake achieved for the inlet gas comprising CO（9.7 mL/min） and He（277.6 mL/min） at a working pressure of 3 MPa after 1 h of Ar purging at 300 mL/min were 12.3 ppm and0.341 mmol/g, respectively. Steam purge could greatly improve the cyclic adsorption working capacity, but had no obvious benefit for the recovery of the residual COconcentration compared to purging with an inert gas. The residual COconcentration obtained with the adsorbent could be reduced to 3.2 ppm after 12 h of temperature swing at 450 °C. A new concept based on an adsorption/desorption process, comprising adsorption, steam rinse, depressurization, steam purge, pressurization, and high-temperature steam purge, was proposed for reducing the steam consumption during CO/COpurification.

关键词： Potassium-promoted hydrotalcite Warm gas clean-up Elevated-temperature pressure swing adsorption CO deep purification High purity hydrogen production

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Two Times Spline Interpolant in Power Exponent Form under the First Boundary Condition

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Journal of Systems Science and Information 2006年第1期4卷 89-95页

作者： ningsheng Yan Department of Fundamental Courses Beijing Institute of Clothing Technology t3eijing 100029 China

In this paper the concept of first boundary condition （i）（i = 0, 1, 2,…, n） is proposed based on [1], the existence of two times spline interpolant under first boundary condition is proved using constructivity me... 详细信息

关键词： two times spline interpolant in power exponent form cubic spline interpolant in power exponent form first boundary condition

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FGF8-mediated signaling regulates tooth developmental pace during odontogenesis

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Journal of Genetics and Genomics 2022年第1期49卷 40-53页

作者： Chensheng Lin ningsheng Ruan Linjun Li Yibin Chen Xiaoxiao Hu YiPing Chen xuefeng Hu Yanding Zhang Fujian Key Laboratory of Developmental and Neural Biology and Southern Center for Biomedical Research College of Life SciencesFujian Normal UniversityFuzhouFujian 350117China Department of Cell and Molecular Biology Tulane UniversityNew OrleansLA 70118USA

The developing human and mouse teeth constitute an ideal model system to study the regulatory mechanism underlying organ growth control since their teeth share highly conserved and well-characterized developmental processes, and their developmental tempo varies notably. In the current study, we manipulated heterogenous recombination between human and mouse dental tissues and demonstrated that the dental mesenchyme dominates the tooth developmental tempo and FGF8 could be a critical player during this developmental process. Forced activation of FGF8 signaling in the dental mesenchyme of mice promoted cell proliferation, prevented cell apoptosis via p38 and perhaps PI3 K-Akt intracellular signaling,and impelled the transition of the cell cycle from G1-to S-phase in the tooth germ, resulting in the slowdown of the tooth developmental pace. Our results provide compelling evidence that extrinsic signals can profoundly affect tooth developmental tempo, and the dental mesenchymal FGF8 could be a pivotal factor in controlling the developmental pace in a non-cell-autonomous manner during mammalian odontogenesis.

关键词： FGF8 Tooth Developmental pace Non-cell-autonomous

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Modelling the temporal-varied nonlinear velocity profile of debris flow using a stratification aggregation algorithm in 3D-HBP-SPH framework

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Journal of Mountain Science 2024年第12期21卷 3945-3960页

作者： HAN Zheng XIE Wendu ZENG Chuicheng LI Yange CHEN Guangqi CHEN ningsheng HU Guisheng WANG Weidong School of Civil Engineering Central South UniversityChangsha 410075China Hunan Provincial Key Laboratory for Disaster Prevention and Mitigation of Rail Transit Engineering Structures Changsha 410075China The Key Laboratory of Engineering Structures of Heavy Haul Railway Ministry of EducationChangsha 410075China Department of Civil Engineering Kyushu UniversityFukuoka 819-0395Japan Key Lab of Mountain Hazards and Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Estimation of velocity profile within mud depth is a long-standing and essential problem in debris flow *** now,various velocity profiles have been proposed based on the fitting analysis of experimental measurements,but these are often limited by the observation conditions,such as the number of configured ***,the resulting linear velocity profiles usually exhibit limitations in reproducing the temporal-varied and nonlinear behavior during the debris flow *** this study,we present a novel approach to explore the debris flow velocity profile in detail upon our previous 3D-HBPSPH numerical model,i.e.,the three-dimensional Smoothed Particle Hydrodynamic model incorporating the Herschel-Bulkley-Papanastasiou ***,we propose a stratification aggregation algorithm for interpreting the details of SPH particles,which enables the recording of temporal velocities of debris flow at different mud *** analyze the velocity profile,we introduce a logarithmic-based nonlinear model with two key parameters,that a controlling the shape of velocity profile and b concerning its temporal *** verify the proposed velocity profile and explore its sensitivity using 34 sets of velocity data from three individual flume experiments in previous *** results demonstrate that the proposed temporalvaried nonlinear velocity profile outperforms the previous linear profiles.

关键词： Debris flow Velocity profile Temporal varied feature Nonlinear Stratification aggregation algorithm

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