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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change Sea level variance X-bar S control charts
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Effect of psychological nursing intervention on anxiety level and quality of life in patients with gastrointestinal peptic ulcer
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作者 Xiao-Rong Zhang Yan-Song Li Ya-Na Xu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2953-2960,共8页
BACKGROUND Peptic ulcer is a common gastrointestinal disease,and psychological intervention has an important influence on its occurrence and development.AIM To investigate the effect of psychological nursing intervent... BACKGROUND Peptic ulcer is a common gastrointestinal disease,and psychological intervention has an important influence on its occurrence and development.AIM To investigate the effect of psychological nursing intervention on the anxiety level and quality of life of patients with gastrointestinal peptic ulcers.METHODS Two groups of patients with peptic ulcer were selected from January to December 2012,with 60 cases in each group,and psychological nursing intervention and routine treatment were respectively performed.Psychological nursing interven-tions include cognitive behavioral therapy,psychological support and relaxation training.Self-rating anxiety scale(SAS)and quality of life questionnaire were used to evaluate the anxiety level and quality of life of patients before,during and after treatment.RESULTS The SAS scores of the experimental group significantly decreased over the course of treatment,from 52.3 before treatment to 30.5 after treatment,while SAS scores of the control group did not change significantly.Meanwhile,the experimental group's quality of life score(SF-36)significantly improved over the course of treatment,from 65.2 to 85.2,while the control group remained stable.Further analysis showed that sex and age had no significant influence on the effect of psychotherapy.Both men and women,young and old,showed similar trends in anxiety relief and improved quality of life after treatment.CONCLUSION Psychological nursing-based intervention program has a positive effect on the anxiety level and quality of life of patients with gastrointestinal peptic ulcer. 展开更多
关键词 Gastrointestinal peptic ulcer Psychological nursing anxiety level Quality of life Cognitive behavioral therapy
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Spatio-temporal variation of depth to groundwater level and its driving factors in arid and semi-arid regions of India
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作者 Suchitra PANDEY Geetilaxmi MOHAPATRA Rahul ARORA 《Regional Sustainability》 2024年第2期103-122,共20页
Climate change and increasing anthropogenic activities,such as over-exploitation of groundwater,are exerting unavoidable stress on groundwater resources.This study investigated the spatio-temporal variation of depth t... Climate change and increasing anthropogenic activities,such as over-exploitation of groundwater,are exerting unavoidable stress on groundwater resources.This study investigated the spatio-temporal variation of depth to groundwater level(DGWL)and the impacts of climatic(precipitation,maximum temperature,and minimum temperature)and anthropogenic(gross district product(GDP),population,and net irrigated area(NIA))variables on DGWL during 1994-2020.The study considered DGWL in 113 observation wells and piezometers located in arid western plains(Barmer and Jodhpur districts)and semi-arid eastern plains(Jaipur,Ajmer,Dausa,and Tonk districts)of Rajasthan State,India.Statistical methods were employed to examine the annual and seasonal patterns of DGWL,and the generalized additive model(GAM)was used to determine the impacts of climatic and anthropogenic variables on DGWL.During 1994-2020,except for Barmer District,where the mean annual DGWL was almost constant(around 26.50 m),all other districts exhibited increase in DGWL,with Ajmer District experiencing the most increase.The results also revealed that 36 observation wells and piezometers showed a statistically significant annual increasing trend in DGWL and 34 observation wells and piezometers exhibited a statistically significant decreasing trend in DGWL.Similarly,32 observation wells and piezometers showed an statistically significant increasing trend and 37 observation wells and piezometers showed a statistically significant decreasing trend in winter;33 observation wells and piezometers indicated a statistically significant increasing trend and 34 had a statistically significant decreasing trend in post-monsoon;35 observation wells and piezometers exhibited a statistically significant increasing trend and 32 observation wells and piezometers showed a statistically significant decreasing trend in pre-monsoon;and 36 observation wells and piezometers reflected a statistically significant increasing trend and 30 observation wells and piezometers reflected a statistically significant decreasing trend in monsoon.Interestingly,most of the observation wells and piezometers with increasing trends of DGWL were located in Dausa and Jaipur districts.Furthermore,the GAM analysis revealed that climatic variables,such as precipitation,significantly affected DGWL in Barmer District,and DGWL in all other districts was influenced by anthropogenic variables,including GDP,NIA,and population.As a result,stringent regulations should be implemented to curb excessive groundwater extraction,manage agricultural water demand,initiate proactive aquifer recharge programs,and strengthen sustainable management in these water-scarce regions. 展开更多
关键词 Climate change Generalized additive model(GaM) Depth to groundwater level(DGWL) Climatic and anthropogenic variables arid and semi-arid regions
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Abnormal Thyroid Stimulating Hormone Level and Heavy Menstrual Bleeding
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作者 Varatharaja Vasantharaja Registrar 《Open Journal of Obstetrics and Gynecology》 2024年第1期110-123,共14页
Heavy Menstrual Bleeding is one of the common Gynaecological issues. There are several causes. Some of the women presented with these issues found to have underling thyroid abnormality which was not discovered earlier... Heavy Menstrual Bleeding is one of the common Gynaecological issues. There are several causes. Some of the women presented with these issues found to have underling thyroid abnormality which was not discovered earlier. This research tries to find the prevalence of the Thyroid Disorder among the women present with Heavy menstrual bleeding in Sri Lankan women. 展开更多
关键词 Heavy Menstrual Bleeding TSH levels Thyroid Disorders
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Shaped beam pattern synthesis with desired nulling level and minimum sidelobe level
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作者 Li-Ming Xu Qiang-Jian Song +3 位作者 Shi-Wen Lei Bo Chen Jing Tian Hao-Quan Hu 《Journal of Electronic Science and Technology》 CAS CSCD 2023年第1期35-45,共11页
For the anti-interference/denoise purpose,it usually requires minimizing the sidelobe level(SLL)of a wide-beam pattern with a desired low nulling level(NL)in the nulling region.To realize such an objective,the shaped-... For the anti-interference/denoise purpose,it usually requires minimizing the sidelobe level(SLL)of a wide-beam pattern with a desired low nulling level(NL)in the nulling region.To realize such an objective,the shaped-beam pattern synthesis(SBPS)is the most commonly used approach.However,since the SBPS problem focuses on synthesizing a predetermined beam shape,the minimum SLL via this approach cannot ensure to obtain the maximum power gain.Conversely,it cannot obtain the lowest SLL with a certain power gain requirement.Based on such consideration,this paper tries to further minimize SLL of a wide-beam pattern with a desired low NL nulling region,by solving the power gain pattern synthesis(PGPS)problem.The PGPS problem selects the array excitation by directly optimizing the power gain.Hence,it has the potential to reduce SLL,when achieving the equal mainlobe power gain constraint via SBPS.An iterative algorithm which converts the primal optimization problem into convex sub-problems is proposed,resulting in an effective problem-solving scheme.Numerical simulations demonstrate the proposed algorithm can obtain about 10-dB lower SLL than the existing algorithms. 展开更多
关键词 array synthesis Minimum sidelobe level(SLL) Nulling level(NL) Pattern synthesis Wide-beam
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A new decomposition model of sea level variability for the sea level anomaly time series prediction
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作者 Qinting SUN Jianhua WAN +2 位作者 Shanwei LIU Jinghui JIANG Yasir MUHAMMAD 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第5期1629-1642,共14页
Rising sea level is of great significance to coastal societies;predicting sea level extent in coastal regions is critical.When carrying out predictions,the subsequences obtained using decomposition methods may exhibit... Rising sea level is of great significance to coastal societies;predicting sea level extent in coastal regions is critical.When carrying out predictions,the subsequences obtained using decomposition methods may exhibit a certain regularity and therefore can provide multidimensional information that can be used to improve prediction models.Traditional decomposition methods such as seasonal and trend decomposition using Loess(STL)focus mostly on the fluctuating trend of time series and ignore its impact on prediction.Methods in the signal decomposition domain,such as variational mode decomposition(VMD),have no physical significance.In response to the above problems,a new decomposition method for sea level anomaly time series prediction(DMSLAP)is proposed.With this method,the trend term in a time series can be isolated and the effects of abnormal sea level change behaviors can be attenuated.We decompose multiperiod characteristics using this method while maintaining the smoothness of the analyzed series.Satellite altimetry data from 1993 to 2020 are used in experiments conducted in the study area.The results are then compared with predictions obtained using existing decomposition methods such as the STL and VMD methods and time varying filtering based on empirical mode decomposition(TVF-EMD).The performance of DMSLAP combined with a prediction method resulted in optimal sea level anomaly(SLA)predictions,with a minimum root mean square error(RMSE)of 1.40 cm and a maximum determination coefficient(R^(2))of 0.93 during 2020.The DMSLAP method was more accurate when predicting 1-year data and 3-year data.The TVF-EMD and DMSLAP methods had comparable accuracies,and the periodic term decomposed by the DMSLAP method was more in line with the actual law than that derived using the TVF-EMD method.Thus,DMSLAP can decompose SLA time series better than existing methods and is an effective tool for obtaining short-term SLA prediction. 展开更多
关键词 time series decomposition satellite altimetry China Sea and its vicinity sea level change
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Organic Carbon Deposition on the Inner Shelf of the East China Sea Constrained by Sea Level and Climatic Changes Since the Last Deglaciation
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作者 ZHANG Mingyu LIU Xiting +7 位作者 XU Fangjian LI Anchun GU Yu CHANG Xin ZHUANG Guangchao ZHANG Kaidi BI Naishuang WANG Houjie 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1300-1312,共13页
The East China Sea(ECS),which is located in the transitional zone between land and ocean,is the main site for the burial of sedimentary organic carbon.Despite good constraints of the modern source to the sinking proce... The East China Sea(ECS),which is located in the transitional zone between land and ocean,is the main site for the burial of sedimentary organic carbon.Despite good constraints of the modern source to the sinking process of organic carbon,its fate in response to changes in climate and sea level since the last deglaciation remains poorly understood.We aim to fill this gap by presenting a high-resolution sedimentary record of core EC2005 to derive a better understanding of the evolution of the depositional environment and its control on the organic deposition since 17.3 kyr.Our results suggest that sedimentary organic carbon was deposited in a terrestrial environment before the seawater reached the study area around 13.1 kyr.This significant transition from a terrestrial environment to a marine environment is reflected by the decrease in TOC/TN and TOC/TS ratios,which is attributed to deglacial sea level rise.The sea level continued to rise until it reached its highstand at approximately 7.3 kyr when the mud depocenter was developed.Our results further indicate that the deposition of the sedimentary organic carbon could respond quickly to abrupt cold events,including the Heinrich stadial 1 and the Younger Dryas during the last deglaciation,as well as‘Bond events'during the Holocene.We propose that the rapid response of the organic deposition to those cold events in the northern hemisphere is linked to the East Asian winter monsoon.These new findings demonstrate that organic carbon deposition and burial on the inner shelf could effectively document sea level and climatic changes. 展开更多
关键词 organic carbon East China Sea mud sediments sea level changes environmental evolution
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Relation between Economic Development Level and Resource and Environment Carrying Capacity of Central Area of Yunnan Province Based on Decoupling Analysis 被引量:4
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作者 程超 童绍玉 +2 位作者 彭海英 闫少凯 刘玲 《Agricultural Science & Technology》 CAS 2015年第12期2829-2832,共4页
Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling ... Based on the decoupiing theory and method, an indicator system was built for the relation between economic development level and resource and environment carrying capacity. And the study was carried out on decoupling degree and temporal changes of economic development level and resource and environment carrying ca- pacity in the central area of Yunnan Province. Results indicated that (i) the economic development level and resource and environment carrying capacity in the central area of Yunnan Province mainly experienced strong decoupling, weak decoupling, and ex- pansive negative coupling, and in general it was strong decoupling, and it took on re- verse "N" in temporal changes. (ii) Change rate of economic development level in the central area of Yunnan Province was greater than zero, but the amplitude of change was not large, while the change rate of resource and environment carrying capacity was negative in 2007-2008, and it was positive in the rest years; from 2007, it took on gradual expansion trend, and scissors difference gradually increased after experi- encing reverse "V" change. (iii) The strong decoupling was the main situation and it reached the peak value in T5 period and T6 pedod. 展开更多
关键词 The central area of Yunnan Province Economic development level Re- source and environment carrying capacity Decoupling analysis Scissors difference
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Effects of Nitrogen Level and High Temperature Stress on Yield, SPAD Value and Soluble Sugar Content of Early Rice Ganxin 203 被引量:2
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作者 杨军 余秋英 +10 位作者 陈小荣 朱昌兰 彭小松 贺晓鹏 傅军如 欧阳林娟 边建民 胡丽芳 孙晓棠 徐杰 贺浩华 《Agricultural Science & Technology》 CAS 2016年第2期385-390,共6页
This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar con... This study aimed to investigate the combined effects of nitrogen level (high and ordinary) and high temperature stress (37 ℃, 4 d) at the late panicle ini- tiation stage on yield, SPAD value and soluble sugar content of Ganxin 203, an early rice cultivar. The results showed that under both high and ordinary nitrogen levels, high temperature stress reduced the seed-setting rate, yield per stem, SPAD value and soluble sugar content of Ganxin 203; under both high and ordinary tem- peratures, high nitrogen level increased the seed-setting rate, yield per stem and soluble sugar content of Ganxin 203; the seed-setting rate, yield per stem and yield per plant of Ganxin 203 under high temperature and high nitrogen level were higher than those under high temperature and ordinary nitrogen level. It suggests that ap- propriate high nitrogen level contributes to weakening the negative effects of high temperature stress on rice yield. 展开更多
关键词 RICE Late panicle initiation stage High temperature YIELD SPaD value Nitrogen level
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Coral Reef and High Sea Level at Luhuitou, Hainan Island during the Holocene 被引量:2
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作者 黄德银 施祺 张叶春 《Marine Science Bulletin》 CAS 2007年第2期61-70,共10页
According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-st... According to the field survey and ^14C dating at Luhuitou, southern Hainan Island, a subsiding area, the authors conclude the high sea level history recorded by coral reef in the Holocene. At least 4 sea level high-stands can be identified from the distribution of coral reef ages: 7300 - 6000 cal.aBP, 4800 - 4700 cal.aBP, 4300 - 4200 cal.aBP and 3100 - 2900 cal.aBP. The highest sea level occurred around 7300 - 6700 cal.aBP, and biological-morphological zones took their shape during the stage. The later coral reefs developed in ponds, depressions, and developed outwards on both sides of Luhuitou peninsula. The modern coral reefs are developing in out reef flat and reef-front slope. Moreover, the time of high sea levels in the northern South China Sea recorded by coral reefs in the Luhuitou peninsula can link up with that in other parts of South China Sea. That means the high sea levels in the South China Sea during the Holocene, which are relative to the warming climate, have the global background. 展开更多
关键词 coral reef high sea level Luihuitou HOLOCENE
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Effect of Fertilizing Level and Planting Densities on Yield and Nitrogen Utilization in Maize 被引量:1
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作者 谭华 邹成林 +7 位作者 郑德波 黄爱花 莫润秀 韦新兴 吴永升 蒋维萍 韦慧 黄开健 《Agricultural Science & Technology》 CAS 2015年第3期504-509,共6页
Elite maize hybrid Guidan0810 was selected as material, and the effects of fertilizing level and planting densities on yield and nitrogen utilization were dis- cussed in the study. In field experiments as per double-c... Elite maize hybrid Guidan0810 was selected as material, and the effects of fertilizing level and planting densities on yield and nitrogen utilization were dis- cussed in the study. In field experiments as per double-cropping system, 4 main plots (fertilization levels) and 6 subplots (planting densities) were set in a split plot design. The results suggested that yield had close relationship with fertilization levels and planting densities. Different fertilization levels and planting densities significantly affected yield. With the increase of nitrogen fertilization, nitrogen use efficiency, nitrogen agronomic efficiency and nitrogen physiological efficiency declined. Under the same fertilization level, nitrogen use efficiency, nitrogen agronomic efficiency and nitrogen physiological efficiency grew a little with the increase of planting density, so nitrogen efficiency could be improved by regulating planting density. The results also showed that A2 (including N 225.0 kg/hm2, P205 75.0 kg/hm^2, K20 187.5 kg/hm^2) matching to B3 (52 500 plants/hm^2) or B4(60 000 plants/hm^2) was a better design, which could obtain a higher yield in the range of 7 913.2-8 207.8 kg/hm2, respectively. 展开更多
关键词 Maize hybrid Fertilizing level Planting density Effects
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Assimilating the along-track sea level anomaly into the regional ocean modeling system using the ensemble optimal interpolation 被引量:4
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作者 LYU Guokun WANG Hui +3 位作者 ZHU Jiang WANG Dakui XIE Jiping LIU Guimei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2014年第7期72-82,共11页
The ensemble optimal interpolation (EnOI) is applied to the regional ocean modeling system (ROMS) with the ability to assimilate the along-track sea level anomaly (TSLA). This system is tested with an eddy-resol... The ensemble optimal interpolation (EnOI) is applied to the regional ocean modeling system (ROMS) with the ability to assimilate the along-track sea level anomaly (TSLA). This system is tested with an eddy-resolving system of the South China Sea (SCS). Background errors are derived from a running seasonal ensemble to account for the seasonal variability within the SCS. A fifth-order localization function with a 250 km localization radius is chosen to reduce the negative effects of sampling errors. The data assimilation system is tested from January 2004 to December 2006. The results show that the root mean square deviation (RMSD) of the sea level anomaly decreased from 10.57 to 6.70 cm, which represents a 36.6% reduction of error. The data assimilation reduces error for temperature within the upper 800 m and for salinity within the upper 200 m, although error degrades slightly at deeper depths. Surface currents are in better agreement with trajectories of surface drifters after data assimilation. The variance of sea level improves significantly in terms of both the amplitude and position of the strong and weak variance regions after assimilating TSLA. Results with AGE error (AGE) perform better than no AGE error (NoAGE) when considering the improvements of the temperature and the salinity. Furthermore, reasons for the extremely strong variability in the northern SCS in high resolution models are investigated. The results demonstrate that the strong variability of sea level in the high resolution model is caused by an extremely strong Kuroshio intrusion. Therefore, it is demonstrated that it is necessary to assimilate the TSLA in order to better simulate the SCS with high resolution models. 展开更多
关键词 ensemble optimal interpolation regional ocean modeling system along-track sea level anomaly South China Sea variability
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High level architecture evolved modular federation object model 被引量:3
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作者 Wang Wenguang Xu Yongping +3 位作者 Chen Xinx Chen Xin Li Qun Wang Weiping 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期625-635,共11页
To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic federation object model (FOM), a modular FOM is proposed by high level architecture (HLA) evolved p... To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic federation object model (FOM), a modular FOM is proposed by high level architecture (HLA) evolved product development group. This paper reviews the state-of-the-art of HLA evolved modular FOM. In particular, related concepts, the overall impact on HLA standards, extension principles, and merging processes are discussed. Also permitted and restricted combinations, and merging rules are provided, and the influence on HLA interface specification is given. The comparison between modular FOM and base object model (BOM) is performed to illustrate the importance of their combination. The applications of modular FOM are summarized. Finally, the significance to facilitate compoable simulation both in academia and practice is presented and future directions are pointed out. 展开更多
关键词 MODEL federation object model REVIEW modular federation object model base object model COMPOSaBILITY high level architecture evolved simulation.
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The impact of mean dynamic topography on a sea-level anomaly assimilation in the South China Sea based on an eddy-resolving model 被引量:2
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作者 XU Dazhi ZHU Jiang +2 位作者 QI Yiquan LI Xichen YAN Youfang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第5期11-25,共15页
The sea-level anomaly (SLA) from a satellite altimeter has a high accuracy and can be used to improve ocean state estimation by assimilation techniques. However, the lack of an accurate mean dynamic topography (MDT... The sea-level anomaly (SLA) from a satellite altimeter has a high accuracy and can be used to improve ocean state estimation by assimilation techniques. However, the lack of an accurate mean dynamic topography (MDT) is still a bothersome issue in an ocean data assimilation. The previous studies showed that the errors in MDT have significant impacts on assimilation results, especially on the time-mean components of ocean states and on the time variant parts of states via nonlinear ocean dynamics. The temporal-spatial differences of three MDTs and their impacts on the SLA analysis are focused on in the South China Sea (SCS). The theoretical analysis shows that even for linear models, the errors in MDT have impacts on the SLA analysis using a sequential data assimilation scheme. Assimilation experiments, based on EnOI scheme and HYCOM, with three MDTs from July 2003 to June 2004 also show that the SLA assimilation is very sensitive to the choice of different MDTs in the SCS with obvious differences between the experimental results and observations in the centre of the SCS and in the vicinity of the Philippine Islands. A new MDT for assimilation of SLA data in the SCS was proposed. The results from the assimilation experiment with this new MDT show a marked reduction (increase) in the RMSEs (correlation coefficient) between the experimental and observed SLA. Furthermore, the subsurface temperature field is also improved with this new MDT in the SCS. 展开更多
关键词 data assimilation mean dynamic topography sea level anomaly South China Sea
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Defect suppression and energy level alignment in formamidinium-based perovskite solar cells 被引量:1
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作者 Yi Wang Xiaobing Wang +9 位作者 Chenhui Wang Renying Cheng Lanxin Zhao Xu Wang Xuewen Zhang Jingzhi Shang Huang Zhang Lichen Zhao Yongguang Tu Wei Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期65-72,共8页
The vast majority of high-performance perovskite solar cells(PSCs) are based on a formamidinium lead iodide(FAPbI_(3))-dominant composition. Nevertheless, the FA-based perovskite films suffer from undesirable phase tr... The vast majority of high-performance perovskite solar cells(PSCs) are based on a formamidinium lead iodide(FAPbI_(3))-dominant composition. Nevertheless, the FA-based perovskite films suffer from undesirable phase transition and defects-induced non-ideal interfacial recombination, which significantly induces energy loss and hinders the improvement of device performance. Herein, we employed 4-fluorophenylmethylammonium iodide(F-PMAI) to modulate surface structure and energy level alignment of the FA-based perovskite films. The superior optoelectronic films were obtained with reduced trap density, pure α-phase FAPbI_(3) and favorable energy band bending. The lifetime of photogenerated charge carriers increased from 489.3 ns to 1010.6 ns, and a more “p-type” perovskite film was obtained by the post-treatment with F-PMAI. Following this strategy, we demonstrated an improved power conversion efficiency of 22.59% for the FA-based PSCs with an open-circuit voltage loss of 399 m V. 展开更多
关键词 Perovskite solar cells Defect suppression Energy level alignment Phase transition 4-Fluorophenylmethylammonium iodide
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Spatiotemporal characteristics of the sea level anomaly in the Kuroshio Extension using a self-organizing map 被引量:1
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作者 MA Fang DIAO Yi-Na LUO De-Hai 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第6期471-478,共8页
Satellite altimeter SSH data in the Kuroshio Extension (KE) region gathered during the period January 1993 to December 2014 are analyzed using self-organizing map (SOM) analysis. Four spatial patterns (SOM1, SOM2... Satellite altimeter SSH data in the Kuroshio Extension (KE) region gathered during the period January 1993 to December 2014 are analyzed using self-organizing map (SOM) analysis. Four spatial patterns (SOM1, SOM2, SOM3, and SOM4) are extracted, and the corresponding time series are used to characterize the variation of the sea level anomaly. Except in some individual months, SOM1 and SOM2 with single-branch jet structures appear alternately during the periods 1993-1998 and 2002-2011. However, during 1999-2001 and 2012-2014, SOM3 and SOM4 with double-branch jet structures are dominant.The sea level anomalies exhibit interannual variations, while the KE stream demonstrates decadal variation. For SOM1, the change in the KE path is less evident, although the KE jet is strong and narrow. For SOM2, the KE jet is weakened and widened and its jet axis moves towards the southwest. Compared with the SOM3, for SOM4 the trough and ridge in the upstream KE region are deeper in the northeast-southwest direction, and accompanied by a jet weakening and splitting.This study shows that SOM analysis is a useful approach for characterizing KE variability. 展开更多
关键词 Sea level anomaly selforganizing map analysis self-organizing map patterns jet variability
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Causes of seasonal sea level anomalies in the coastal region of the East China Sea 被引量:3
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作者 WANG Hui LIU Kexiu +4 位作者 QI Dongmei GAO Zhigang FAN Wenjing ZHANG Zengjian WANG Guosong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第3期21-29,共9页
Based on the analysis of sea level, air temperature, sea surface temperature(SST), air pressure and wind data during 1980-2013, the causes of seasonal sea level anomalies in the coastal region of the East China Sea... Based on the analysis of sea level, air temperature, sea surface temperature(SST), air pressure and wind data during 1980-2013, the causes of seasonal sea level anomalies in the coastal region of the East China Sea(ECS) are investigated. The research results show:(1) sea level along the coastal region of the ECS takes on strong seasonal variation. The annual range is 30-45 cm, larger in the north than in the south. From north to south, the phase of sea level changes from 140° to 231°, with a difference of nearly 3 months.(2) Monthly mean sea level(MSL)anomalies often occur from August to next February along the coast region of the ECS. The number of sea level anomalies is at most from January to February and from August to October, showing a growing trend in recent years.(3) Anomalous wind field is an important factor to affect the sea level variation in the coastal region of the ECS. Monthly MSL anomaly is closely related to wind field anomaly and air pressure field anomaly. Wind-driven current is essentially consistent with sea surface height. In August 2012, the sea surface heights at the coastal stations driven by wind field have contributed 50%-80% of MSL anomalies.(4) The annual variations for sea level,SST and air temperature along the coastal region of the ECS are mainly caused by solar radiation with a period of12 months. But the correlation coefficients of sea level anomalies with SST anomalies and air temperature anomalies are all less than 0.1.(5) Seasonal sea level variations contain the long-term trends and all kinds of periodic changes. Sea level oscillations vary in different seasons in the coastal region of the ECS. In winter and spring, the oscillation of 4-7 a related to El Ni?o is stronger and its amplitude exceeds 2 cm. In summer and autumn, the oscillations of 2-3 a and quasi 9 a are most significant, and their amplitudes also exceed 2 cm. The height of sea level is lifted up when the different oscillations superposed. On the other hand, the height of sea level is fallen down. 展开更多
关键词 sea level anomalies ECS wind air pressure SST air temperature oscillations
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Characteristics and possible causes of the seasonal sea level anomaly along the South China Sea coast 被引量:1
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作者 WANG Hui LIU Kexiu +3 位作者 GAO Zhigang FAN Wenjing LIU Shouhua LI Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期9-16,共8页
Based on sea level, air temperature, sea surface temperature(SST), air pressure and wind data during 1980–2014,this paper uses Morlet wavelet transform, Estuarine Coastal Ocean Model(ECOM) and so on to investigat... Based on sea level, air temperature, sea surface temperature(SST), air pressure and wind data during 1980–2014,this paper uses Morlet wavelet transform, Estuarine Coastal Ocean Model(ECOM) and so on to investigate the characteristics and possible causes of seasonal sea level anomalies along the South China Sea(SCS) coast. The research results show that:(1) Seasonal sea level anomalies often occur from January to February and from June to October. The frequency of sea level anomalies is the most in August, showing a growing trend in recent years. In addition, the occurring frequency of negative sea level anomaly accounts for 50% of the total abnormal number.(2) The seasonal sea level anomalies are closely related to ENSO events. The negative anomalies always occurred during the El Ni?o events, while the positive anomalies occurred during the La Ni?a(late El Ni?o) events. In addition, the seasonal sea level oscillation periods of 4–7 a associated with ENSO are the strongest in winter, with the amplitude over 2 cm.(3) Abnormal wind is an important factor to affect the seasonal sea level anomalies in the coastal region of the SCS. Wind-driven sea level height(SSH) is basically consistent with the seasonal sea level anomalies. Moreover, the influence of the tropical cyclone in the coastal region of the SCS is concentrated in summer and autumn, contributing to the seasonal sea level anomalies.(4) Seasonal variations of sea level, SST and air temperature are basically consistent along the coast of the SCS, but the seasonal sea level anomalies have no much correlation with the SST and air temperature. 展开更多
关键词 seasonal sea level anomalies ENSO wind air pressure oscillations
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Characteristics and possible causes of sea level anomalies in the Xisha sea area
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作者 WANG Hui HAN Shuzong +3 位作者 FAN Wenjing WANG Guosong LIU Kexiu ZHANG Zengjian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第9期34-41,共8页
Based on the analysis of wind,ocean currents,sea surface temperature(SST) and remote sensing satellite altimeter data,the characteristics and possible causes of sea level anomalies in the Xisha sea area are investig... Based on the analysis of wind,ocean currents,sea surface temperature(SST) and remote sensing satellite altimeter data,the characteristics and possible causes of sea level anomalies in the Xisha sea area are investigated.The main results are shown as follows:(1) Since 1993,the sea level in the Xisha sea area was obviously higher than normal in 1998,2001,2008,2010 and 2013.Especially,the sea level in 1998 and 2010 was abnormally high,and the sea level in 2010 was 13.2 cm higher than the muti-year mean,which was the highest in the history.In 2010,the sea level in the Xisha sea area had risen 43 cm from June to August,with the strength twice the annual variation range.(2) The sea level in the Xisha sea area was not only affected by the tidal force of the celestial bodies,but also closely related to the quasi 2 a periodic oscillation of tropical western Pacific monsoon and ENSO events.(3)There was a significant negative correlation between sea level in the Xisha sea area and ENSO events.The high sea level anomaly all happened during the developing phase of La Ni-a.They also show significant negative correlations with Ni-o 4 and Ni-o 3.4 indices,and the lag correlation coefficients for 2 months and 3 months are–0.46 and –0.45,respectively.(4) During the early La Ni-a event form June to November in 2010,the anomalous wind field was cyclonic.A strong clockwise vortex was formed for the current in 25 m layer in the Xisha sea area,and the velocity of the current is close to the speed of the Kuroshio near the Luzon Strait.In normal years,there is a “cool eddy”.While in 2010,from July to August,the SST in the area was 2–3°C higher than that of the same period in the history. 展开更多
关键词 Xisha sea area sea level anomalies ENSO wind current SST
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Sea level anomalies in the northwestern Pacific during 2011 associated with La Nina and negative Indian Ocean Dipole
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作者 Fuwen Qiu Yun Qiu +2 位作者 Aijun Pan Jing Cha Shanwu Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第11期62-69,共8页
The sea level anomalies(SLAs)pattern in the northwestern Pacific delineated significant differences between La Ni?a events occurring with and without negative Indian Ocean Dipole(IOD)events.During the pure La Ni?a eve... The sea level anomalies(SLAs)pattern in the northwestern Pacific delineated significant differences between La Ni?a events occurring with and without negative Indian Ocean Dipole(IOD)events.During the pure La Ni?a events,positive the sea surface level anomalies(SLAs)appear in the northwestern Pacific,but SLAs are weakened and negative SLAs appear in the northwestern Pacific under the contribution of the negative IOD events in 2010/2011.The negative IOD events can trigger significant westerly wind anomalies in the western tropical Pacific,which lead to the breakdown of the pronounced positive SLAs in the northwestern Pacific.Meanwhile,negative SLAs excited by the positive wind stress curl near the dateline propagated westward in the form of Rossby waves until it approached the western Pacific boundary in mid-2011,which maintained and enhanced the negative phase of SLAs in the northwestern Pacific and eventually,it could significantly influence the bifurcation and transport of the North Equatorial Current(NEC). 展开更多
关键词 sea level anomalies La Nina negative IOD northwestern Pacific
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