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Projected Changes in Temperature and Precipitation Extremes over China as Measured by 50-yr Return Values and Periods Based on a CMIP5 Ensemble 被引量:15
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作者 Ying XU Xuejie GAO +4 位作者 Filippo GIORGI Botao ZHOU Ying SHI Jie WU Yongxiang ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2018年第4期376-388,共13页
Future changes in the 50-yr return level for temperature and precipitation extremes over China's Mainland are investigated based on a CMIP5 multi-model ensemble for RCP2.6, RCP4.5 and RCP8.5 scenarios. The followi... Future changes in the 50-yr return level for temperature and precipitation extremes over China's Mainland are investigated based on a CMIP5 multi-model ensemble for RCP2.6, RCP4.5 and RCP8.5 scenarios. The following indices are analyzed: TXx and TNn (the annual maximum and minimum of daily annual maximum consecutive 5-day precipitation) and CDD maximum and minimum surface temperature), RX5day (the (maximum annual number of consecutive dry days). After first validating the model performance, future changes in the 50-yr return values and return periods for these indices are investigated along with the inter-model spread. Multi-model median changes show an increase in the 50-yr return values of TXx and a decrease for TNn, more specifically, by the end of the 21st century under RCP8.5, the present day 50-yr return period of warm events is reduced to 1.2 yr, while extreme cold events over the country are projected to essentially disappear. A general increase in RX5day 50-yr return values is found in the future. By the end of the 21st century under RCP8.5, events of the present RX5day 50-yr return period are projected to reduce to 〈 10 yr over most of China. Changes in CDD-50 show a dipole pattern over China, with a decrease in the values and longer return periods in the north, and vice versa in the south. Our study also highlights the need for further improvements in the representation of extreme events in climate models to assess the future risks and engineering design related to large-scale infrastructure in China. 展开更多
关键词 CMIP5 EXTREMES return values and periods China
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Clinical Application of Sex Hormone in Different Physiological Periods in the Diagnosis of Infertility Patients
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作者 Jianhong Nong Daxian Tan +4 位作者 Arshad Mehmood Tingchao Wang Xin Liu Li Deng Bowen Wei 《Natural Science》 2024年第6期102-110,共9页
Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different ... Background: Infertility is characterized by the inability to conceive after a year of regular unprotected intercourse. Aims: This study aimed to investigate the diagnostic value of sex hormone levels during different physiological periods in the diagnosis of infertility patients. Methods: From December 2019 to May 2021, a total of 93 infertility patients were admitted and selected as the observation group. Among them, 31 cases were in the follicular stage, 31 cases in the ovulation stage, and 31 cases in the luteal stage. Ninety-three healthy women for fertility evaluation due to male infertility were selected as the control group. The control group included 31 women in the follicular phase, 31 women in the ovulatory phase, and 31 women in the luteal phase. The levels of sex hormones (prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E2), testosterone (T), and progesterone (P)) during different physiological phases were compared between the observation and control groups. Results: The follicular phase showed no significant difference in LH levels between the observation group and the control group. The observation group showed higher levels of PRL and P compared to the control group, while the levels of FSH, E2, and T were lower in the observation group compared to the control group. The ovulation phase showed no significant difference in PRL levels between the two groups. The observation group showed lower levels of LH, FSH, E2, T, and P compared to the control group. The luteal phase showed no statistical difference in E2 levels between the two groups. The observation group showed higher levels of PRL, LH, and FSH compared to the control group, while the levels of T and P were lower in the observation group compared to the control group. Conclusion: Infertile women show variations in hormone levels compared to the normal levels during the follicular phase, ovulatory phase, and luteal phase. 展开更多
关键词 Different periods Sex Hormone Level Detection INFERTILITY Auxiliary Diagnosis
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Oriental Reed Warblers do not abandon Common Cuckoo chicks during prolonged nestling periods
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作者 Hanlin Yan Huahua Zhao +3 位作者 Haixia Luo Longwu Wang Laikun Ma Wei Liang 《Avian Research》 SCIE CSCD 2024年第3期369-373,共5页
The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra repro... The Oriental Reed Warbler(Acrocephalus orientalis)is one of the most commonly used hosts for the parasitic Common Cuckoo(Cuculus canorus).However,as hosts that feed unrelated parasitic nestlings may suffer extra reproductive costs,they may be less willing to care for nestlings that have prolonged nestling periods.To test this hypothesis,the duration of feeding by Oriental Reed Warblers under natural conditions for their own nestlings was compared with the duration of feeding under natural conditions for Common Cuckoo nestlings and for artificially prolonged cuckoo nestlings.The results showed that Oriental Reed Warblers did not starve,drive away,or desert any of the nestlings in the experiment,and neither parent was left alone.Our experimental study indicates that both Oriental Reed Warbler parents were willing to care for nestlings with a prolonged nestling period(up to 30 days,twice the average duration time that the Oriental Reed Warblers fed their own chicks in natural conditions).However,further experiments and observations are required in other host bird species to examine whether both parents or one of the parents may exhibit the behavior of abandoning nestlings with a prolonged nestling period. 展开更多
关键词 Brood parasitism Common Cuckoo Deserted nestling Oriental Reed Warbler Prolonged nestling period
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Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods
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作者 PANG Jinghao LIANG Shen +5 位作者 LIU Yabin LI Shengwei WANG Shu ZHU Haili LI Guorong HU Xiasong 《Journal of Mountain Science》 SCIE CSCD 2024年第3期835-849,共15页
Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic cha... Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery periods.We selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear tests.The results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery period.The shear strength of the rooted soil and the recovery period exhibited a quadratic function relationship.There is no significant function relationship between the peak displacement and the recovery period.Significant positive correlations(P<0.05)exists between the shear strength of the root-soil composite and the root biomass density,root volume density,and root area ratio,and they show significant linear correlations(P<0.05).There are no significant correlations(P>0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P<0.05)exists between the peak displacement of the rooted soil and the coarse-grain content,but no significant correlations(P>0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope gradient.The coarse-grain content is the main factor controlling the peak displacement of the rooted soil. 展开更多
关键词 Alpine mine dump Artificial vegetation restoration period Rooted soil Shear resistance characteristics Root traits Soil physical properties
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Hydrology and Estimation of Real Erosion in the Patria Nueva Micro-Basin for Five Return Periods
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作者 Martín Mundo-Molina José Luis Pérez-Díaz 《Journal of Water Resource and Protection》 CAS 2022年第12期783-789,共7页
This paper will discuss the actual erosion estimation of the Patria Nueva micro basin in tons/ha/year (E), located in Tuxtla Gutiérrez Chiapas, Mexico. We used the universal soil loss equation (USLE), considered ... This paper will discuss the actual erosion estimation of the Patria Nueva micro basin in tons/ha/year (E), located in Tuxtla Gutiérrez Chiapas, Mexico. We used the universal soil loss equation (USLE), considered one of the best theoretical tools for planning and soil preservation in the USA and other countries. The actual erosion rates were estimated for 5, 20, 50, 100, and 500 years return periods (Rp), with elevated results due to high degrees of anthropogenic alteration of the micro-basin, especially in the last 50 years. High erosion rates generate the following problems: loss of soil, which is unfavorable for plant life, due to the soil being a non-renewable resource, the undermine can never renovate, the hydraulic area in the main channel reduces during the rainy season (when the river overflows). The sediment accumulates at the lower part of the micro-basin along with waste, garbage, and mud. 展开更多
关键词 EROSION return periods BASINS USLE SEDIMENT
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Climate Change Characteristics and Return Periods of Heavy Precipitation in the Northeast Side of Qinghai-Tibet Plateau
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作者 Tao Huang 《Meteorological and Environmental Research》 CAS 2013年第7期10-14,共5页
[ Objective] The study aimed to discuss analyze climate change characteristics and return periods of heavy precipitation in the northeast side of Qinghai-Tibet Plateau. [ Method] Based on the data of daily precipitati... [ Objective] The study aimed to discuss analyze climate change characteristics and return periods of heavy precipitation in the northeast side of Qinghai-Tibet Plateau. [ Method] Based on the data of daily precipitation from 1943 to 2008 in 6 representative meteorological stations in Linxia located in the northeast side of Qinghai-Tibet Plateau, the climate change characteristics of heavy precipitation were analyzed, and the return periods of heavy precipitation were calculated by Pearson-Ill probability distribution method. [ Result] Days of heavy precipitation in Linxia region in- creased conspicuously since the 1990s. The return periods of heavy precipitation in the six stations on August 20, 2008 were consistent with the re- sults of artificial estimation. [ Conclusion] The research could provide scientific references for the reasonable utilization of climate resources, disas- ter prevention and rational arranqement of anricultural plantina svstems in Linxia reaion. 展开更多
关键词 Northeast side of Qinghai-Tibet Plateau Climate change Heavy precipitation Characteristic analysis return period China
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Return to work in young and middle-aged colorectal cancer survivors:Factors influencing self-efficacy,fear,resilience,and financial toxicity
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作者 Dan Hu Yue Li +6 位作者 Hua Zhang Lian-Lian Wang Wen-Wen Liu Xin Yang Ming-Zhao Xiao Hao-Ling Zhang Juan Li 《World Journal of Gastroenterology》 SCIE CAS 2025年第1期79-92,共14页
BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their... BACKGROUND Return to work(RTW)serves as an indication for young and middle-aged colorectal cancer(CRC)survivors to resume their normal social lives.However,these survivors encounter significant challenges during their RTW process.Hence,scientific research is necessary to explore the barriers and facilitating factors of returning to work for young and middle-aged CRC survivors.AIM To examine the current RTW status among young and middle-aged CRC survivors and to analyze the impact of RTW self-efficacy(RTW-SE),fear of progression(FoP),eHealth literacy(eHL),family resilience(FR),and financial toxicity(FT)on their RTW outcomes.METHODS A cross-sectional investigation was adopted in this study.From September 2022 to February 2023,a total of 209 participants were recruited through a convenience sampling method from the gastrointestinal surgery department of a class A tertiary hospital in Chongqing.The investigation utilized a general information questionnaire alongside scales assessing RTW-SE,FoP,eHL,FR,and FT.To analyze the factors that influence RTW outcomes among young and middle-aged CRC survivors,Cox regression modeling and Kaplan-Meier survival analysis were used.RESULTS A total of 43.54%of the participants successfully returned to work,with an average RTW time of 100 days.Cox regression univariate analysis revealed that RTW-SE,FoP,eHL,FR,and FT were significantly different between the non-RTW and RTW groups(P<0.05).Furthermore,Cox regression multivariate analysis identified per capita family monthly income,job type,RTW-SE,and FR as independent influencing factors for RTW(P<0.05).CONCLUSION The RTW rate requires further improvement.Elevated levels of RTW-SE and FR were found to significantly increase RTW among young and middle-aged CRC survivors.Health professionals should focus on modifiable factors,such as RTW-SE and FR,to design targeted RTW support programs,thereby facilitating their timely reintegration into mainstream society. 展开更多
关键词 return to work Colorectal neoplasms return-to-work self-efficacy Fear of progression Family resilience Financial toxicity
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Insulin-induced severe thyrotoxic periodic paralysis:A case report
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作者 Yan-Li Wang Jian Li 《World Journal of Clinical Cases》 SCIE 2025年第7期46-51,共6页
BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue... BACKGROUND Thyrotoxic periodic paralysis(TPP)is an endocrine emergency caused by thyrotoxicosis,manifesting mainly as periodic myasthenia and hypokalemia,and posing a serious threat to the patient's health.Fatigue,strenuous exercise,alcohol abuse,high carbohydrate intake and insulin injections are common triggers of paralysis.This article reports a case of severe TPP induced by insulin injection,elucidates the characteristics and pathogenesis of the disease,analyses the risk factors for triggering TPP,and hopefully provides more clinical data for TPP patients.CASE SUMMARY A 38-year-old Asian man presented to the emergency department with a oneweek history of limb weakness and worsening half-day.His medical history included poorly controlled type 2 diabetes and he had been switched to Aspart50 a week earlier.He was alert and oriented with upper extremity strength grade 3 and lower extremity strength grade 1.Emergency department tests showed hypokalemia of 1.6 mmol/L.The paramedics administered 1.5 g of potassium intravenously,followed by 4.0 g orally.Weakness in the arms and legs improved.He was referred to endocrinology where he was diagnosed with Graves'disease,with suboptimal control and insulin injections possibly causing TPP.We stopped his insulin and he was discharged with a potassium level of 4.0 mmol/L.CONCLUSION Insulin is a trigger for TPP and should be avoided in patients with hyperthyroidism.Early recognition and treatment of TPP is crucial,especially in patients presenting with hypokalemic periodic paralysis. 展开更多
关键词 Thyrotoxic periodic paralysis Potassium metabolism disorders INSULIN Triggers of paralysis Case report
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Effect of MnO_4^- and silver content on electrochemical behaviour of Pb-Ag alloy anodes during potential decay periods 被引量:4
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作者 张伟 涂常青 +2 位作者 陈艺锋 Houlachi GEORGEOS 肖利 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2174-2180,共7页
The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay ... The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy (EIS) analysis. 展开更多
关键词 electrochemical behaviour Pb-Ag anode permanganate ion potential decay periods zinc sulphate electrolyte
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Bi-normalized response spectra and scalar periods for developing uniform seismic design spectra 被引量:3
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作者 徐龙军 谢礼立 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期266-271,共6页
Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of... Aiming at the uniform features of acceleration response spectra, two scalar periods-the response spectral predominant period Tp and the smoothed spectral predominant period To are employed to normalize the abscissa of the normalized response spectra (NRS) of ground motions, respectively. Engineering characteristics of 5% -damped NRS, and the bi-normalized response spectra (BNRS) are investigated accounting for the effects of soil condition and fault distance. Nearly 600 horizontal ground motion components during the Chi-Chi earthquake are included in the analysis. It shows that the NRS strongly depends on soil condition and fault distance. However, soil condition and distance have only a slight influence on two kinds of BNRS. Dispersion analysis indicates that such normalization can reduce scatter in the derivation of response spectral shapes. Finally, a parametric analysis of the scalar periods (Tp, To) is performed and then compared with those of previous studies. These special and particular aspects of earthquake response spectra and scalar periods need to be considered in developing earthquake-resistant design criteria. 展开更多
关键词 ground motion normalized response spectrum bi-normalized response spectra scalar period
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Effects of Nitrogen Application Amount during Various Periods on Yield of High Grade Hybrid Rapeseed 被引量:1
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作者 赵继献 任廷波 程国平 《Agricultural Science & Technology》 CAS 2012年第6期1292-1297,共6页
[Objective] The paper was to study the nitrogen application amount and nitrogen application model for high grade hybrid rapeseed (Brassica napus L.) to get high yield. [Method] With "Youyan 599" and "Sanbei 98" ... [Objective] The paper was to study the nitrogen application amount and nitrogen application model for high grade hybrid rapeseed (Brassica napus L.) to get high yield. [Method] With "Youyan 599" and "Sanbei 98" as materials, using quadratic regression orthogonal gyration combination design, the impact of nitrogen application amount during various periods on rapeseed yield was studied. [Result] The combinations of factors to obtain the highest yield index (2 898.211 kg / hm 2 ) of "Youyan 599" were as follows: living rape fertilizer 89.27 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 101.12 kg / hm 2 , total nitrogen application amount 310.39 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12th lunar month fertilizer were 28.76%, 38.66% and 32.58%, respectively. The combinations of factors to obtain the highest yield index (2 870.14 kg/hm 2 ) of "Sanbei 98" were as follows: living rape fertilizer 120 kg / hm 2 , opening fertilizer 120 kg / hm 2 , 12 th lunar month fertilizer 37.55kg / hm 2 , total nitrogen application amount 277.55 kg / hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 43.24%, 43.24% and 13.53%, respectively. The combinations of factors to obtain the highest yield index of two combined varieties (2 813.82 kg/hm 2 )were as follows: living rape fertilizer 120 kg/hm 2 , opening fertilizer 120 kg/hm 2 , 12 th lunar month fertilizer 76.23 kg/hm 2 , total nitrogen application amount 316.23 kg/hm 2 . The proportions of living rape fertilizer, opening fertilizer and 12 th lunar month fertilizer were 37.95% , 37.95% and 24.11% , respectively. [Conclusion] The paper provided theoretical basis for high yield cultivation of high grade hybridized rapeseed. 展开更多
关键词 Hybrid rapeseed Application period of nitrogen fertilizer Application amount of nitrogen PROPORTION
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A new method to estimate wave height of specified return period 被引量:5
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作者 王莉萍 许新 +2 位作者 刘桂林 陈柏宇 陈正寿 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第5期1002-1009,共8页
In this paper, we propose a new method to estimate the wave height of a specifi c return period based on the Hurst rule and a self-affi ne fractal formula. A detailed description of our proposed model is presented in ... In this paper, we propose a new method to estimate the wave height of a specifi c return period based on the Hurst rule and a self-affi ne fractal formula. A detailed description of our proposed model is presented in this paper. We use the proposed model to analyze wave height data recorded along the coast of Chaolian Island from 1963 to 1989. The results show that the performance of our proposed model in estimating design wave heights is superior to traditional models. 展开更多
关键词 Hurst rule SELF-AFFINITY fractal formula wave height of specific return period
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Microphysical Characteristics of Precipitation during Pre-monsoon,Monsoon, and Post-monsoon Periods over the South China Sea 被引量:9
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作者 Qingwei ZENG Yun ZHANG +5 位作者 Hengchi LEI Yanqiong XIE Taichang GAO Lifeng ZHANG Chunming WANG Yanbin HUANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2019年第10期1103-1120,共18页
Raindrop size distribution (RSD) characteristics over the South China Sea (SCS) are examined with onboard Parsivel disdrometer measurements collected during marine surveys from 2012 to 2016. The observed rainfall is d... Raindrop size distribution (RSD) characteristics over the South China Sea (SCS) are examined with onboard Parsivel disdrometer measurements collected during marine surveys from 2012 to 2016. The observed rainfall is divided into premonsoon, monsoon, and post-monsoon periods based on the different large-scale circumstances. In addition to disdrometer data, sounding observation, FY-2E satellite, SPRINTARS (Spectral Radiation-Transport Model for Aerosol Species), and NCEP reanalysis datasets are used to illustrate the dynamical and microphysical characteristics associated with the rainfall in different periods. Significant variations have been observed in respect of raindrops among the three periods. Intercomparison reveals that small drops (D < 1 mm) are prevalent during pre-monsoon precipitation, whereas medium drops (1?3 mm) are predominant in monsoon precipitation. Overall, the post-monsoon precipitation is characterized by the least concentration of raindrops among the three periods. But, several large raindrops could also occur due to severe convective precipitation events in this period. Classification of the precipitation into stratiform and convective regimes shows that the lg(Nw) value of convective rainfall is the largest (smallest) in the pre-monsoon (post-monsoon) period, whereas the Dm value is the smallest (largest) in the pre-monsoon (post-monsoon) period. An inversion relationship between the coefficient A and the exponential b of the Z?R relationships for precipitation during the three periods is found. Empirical relations between Dm and the radar reflectivity factors at Ku and Ka bands are also derived to improve the rainfall retrieval algorithms over the SCS. Furthermore, the possible causative mechanisms for the significant RSD variability in different periods are also discussed with respect to warm and cold rain processes, raindrop evaporation, convective activities, and other meteorological factors. 展开更多
关键词 PRECIPITATION RAINDROP size distribution South China Sea MONSOON period STRATIFORM and convective cloud
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Different characteristics of the structure of atmospheric boundary layer between dry and rainy periods over the northern Tibetan Plateau 被引量:6
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作者 Ishikawa Hirohiko Shinya Ogino 《Research in Cold and Arid Regions》 2011年第6期509-516,共8页
In this paper, based on in-situ observational data of the Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan'Plateau (CAMP-Tibet), structure of the Atmospheric Bou... In this paper, based on in-situ observational data of the Coordinated Enhanced Observing Period (CEOP) Asia-Australia Monsoon Project (CAMP) on the Tibetan'Plateau (CAMP-Tibet), structure of the Atmospheric Boundary Layer (ABL) was preliminarily studied during the dry and rainy seasons. The main results show: (a) Diurnal variation of the ABL is obvious over the northern Tibetan Plateau area. The height of the ABL is different with the season change, which ranges from 2,211 m to 4,430 m during the pre-monsoon season and from 1,006 m to 2,212 m during the monsoon season. The ABL height is higher during the dry period than during the rainyigeriod. (b) The humidity is lower during the dry period than during the rainy period, and there are reverse humidity during both periods. (c) Horizontal wind direction is mostly west during the dry period, east under the height of 2,500 m and west above the height of 2,500 m during the rainy period. The wind speed is low during both the rainy and dry periods in the lower ABL layer. The wind speed is stronger within the upper ABL during the dry period than dtn-ing the rainy period. 展开更多
关键词 Tibetan Plateau structure characteristics alrnospheric boundary layer dry period rainy period
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The difference between the joint probability distributions of apparent wave heights and periods and individual wave heights and periods 被引量:5
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作者 ZHENGGuizhen JIANGXiulan HANShuzong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2004年第3期399-406,共8页
The joint distribution of wave heights and periods of individual waves is usually approximated by the joint distribution of apparent wave heights and periods. However there is difference between them. This difference ... The joint distribution of wave heights and periods of individual waves is usually approximated by the joint distribution of apparent wave heights and periods. However there is difference between them. This difference is addressed and the theoretical joint distributions of apparent wave heights and periods due to Longuet-Higgins and Sun are modified to give more reasonable representations of the joint distribution of wave heights and periods of individual waves. The modification has overcome an inherent drawback of these joint PDFs that the mean wave period is infinite. A comparison is made between the modified formulae and the field data of Goda, which shows that the new formulae consist with the measurement better than their original counterparts. 展开更多
关键词 sea waves wave statistics wave height wave period
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Sequence stratigraphy, paleogeography, and coal accumulation regularity of major coal-accumulating periods in China 被引量:19
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作者 Longyi Shao Xuetian Wang +11 位作者 Dongdong Wang Mingpei Li Shuai Wang Yingjiao Li Kai Shao Chao Zhang Caixia Gao Daxiao Dong Aiguo Cheng Jing Lu Congwei Ji Di Gao 《International Journal of Coal Science & Technology》 EI 2020年第2期240-262,共23页
There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early C... There are 9 major coal-accumulating periods during geological history in China,including the Early Carboniferous,Late Carboniferous-Early Permian,Middle Permian,Late Permian,Late Triassic,Early-Middle Jurassic,Early Cretaceous,Paleogene and Neogene.The coal formed in these periods were developed in different coal-accumulating areas(CAA)including the North China,South China,Northwest China,Northeast China,the Qinghai–Tibet area,and China offshore area.In this paper,we investigated depositional environments,sequence stratigraphy,lithofacies paleogeography and coal accumulation pattern of five major coal-accumulating periods including the Late Carboniferous to Middle Permian of the North China CAA,the Late Permian of the South China CAA,the Late Triassic of the South China CAA,the Early-Middle Jurassic of the North and Northwest China CAA,and the Early Cretaceous in the Northeast China CAA.According to distribution of the coal-bearing strata and the regional tectonic outlines,we have identified distribution range of the coal-forming basins,sedimentary facies types and coal-accumulating models.The sequence stratigraphic frameworks of the major coal-accumulating periods were established based on recognition of a variety of sequence boundaries.The distribution of thick coals and migration patterns of the coal-accumulating centers in the sequence stratigraphic framework were analyzed.The lithofacies paleogeography maps based on third-order sequences were reconstructed and the distribution of coal accumulation centers and coal-rich belts were predicted. 展开更多
关键词 Coal-accumulating period Coal-accumulating area Sequence stratigraphy PALEOGEOGRAPHY China
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Key indicators affecting maize stalk lodging resistance of different growth periods under different sowing dates 被引量:21
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作者 WANG Qun XUE Jun +7 位作者 CHEN Jiang-lu FAN Ying-hu ZHANG Guo-qiang XIE Rui-zhi MING Bo HOU Peng WANG Ke-ru LI Shao-kun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第10期2419-2428,共10页
The accurate evaluation of maize stalk lodging resistance in different growth periods enables timely management of lodging risks and ensures stable and high maize yields.Here,we established five diferent sowing dates ... The accurate evaluation of maize stalk lodging resistance in different growth periods enables timely management of lodging risks and ensures stable and high maize yields.Here,we established five diferent sowing dates to create diferent conditions for maize growth.We evaluated the effects of the different growth conditions on lodging resistance by determining stalk morphology,moisture content,mechanical strength and dry matter,and the relationship between stalk breaking force and these indicators during the silking stage(R1),milk stage(R3),physiological maturity stage(R6),and 20 days after R6.Plant height at R1 positively affected stalk breaking force.At R3,the cofficient of ear height and the dry weight per unit length of basal internodes were key indicators of stalk lodging resistance.At R6,the key indicators were the coefficient of the center of gravity height and plant fresh weight.After R6,the key indicator was the coefficient of the center of gravity height.The crushing strength of the fourth internode correlated significanty and positively with the stalk breaking force from R1 to R6,which indicates that crushing strength is a reliable indicator of stalk mechanical strength.These results suggest that high stalk strength and low ear height beneft lodging resistance prior to R6.During and after R6,the cofficient of the center of gravity height and the mechanical strength of basal internodes can be used to evaluate plant lodging resistance and the appropriate time for harvesting in fields with a high lodging risk. 展开更多
关键词 MAIZE lodging resistance stalk strength growth periods breaking force
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Stability analysis of networked control systems with time-varying sampling periods 被引量:8
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作者 Fuchun LIU Yu YAO FenghuaHE Songlin CHEN 《控制理论与应用(英文版)》 EI 2008年第1期22-25,共4页
In this paper, we present an interval model of networked control systems with time-varying sampling periods and time-varying network-induced delays and discuss the problem of stability of networked control systems usi... In this paper, we present an interval model of networked control systems with time-varying sampling periods and time-varying network-induced delays and discuss the problem of stability of networked control systems using Lyapunov stability theory. A sufficient stability condition is obtained by solving a set of linear matrix inequalities. In the end, the illustrative example demonstrates the correctness and effectiveness of the proposed approach. 展开更多
关键词 Networked control systems (NCS) Time-varying sampling periods Network-induced delay Linear matrix inequality(LMI)
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Stability of growth periods traits for soybean cultivars across multiple locations 被引量:2
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作者 WANG Xiao-bo LIU Zhang-xiong +12 位作者 YANG Chun-yan XU ran LU Wei-guo ZHANG Li-feng WANG Qian WEI Su-hong YANG Chun-ming WANG Hui-cai WANG Rui-zhen ZHOU Rong CHEN Huai-zhu CHANG Ru-zhen QIU Li-juan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第5期963-972,共10页
The growth periods(GPs, from planting/emergence to reproductive stage 8(R8) of soybean cultivars vary in different ecological regions, especially in China with a very complex soybean cropping system. In this study,... The growth periods(GPs, from planting/emergence to reproductive stage 8(R8) of soybean cultivars vary in different ecological regions, especially in China with a very complex soybean cropping system. In this study, a 3-yr experimental study was undertaken in three geographical locations of China from 2008 to 2010, including the Northeast(40.66-45.85°N), Huang-Huai(34.75-38.04°N) and southern(22.82-30.60°N) eco-regions with about 250 accessions in each region to clarify the classification of maturity group(MG) and identify the cultivars with stable GP to increase the knowledge about the GP distribution of soybean cultivars in China. GPs of soybean cultivars in different eco-regions were significant different with a gradual decrease from 115-125 d in the Northeast part to the 85-100 d in the southern part of China. The geographical location was the major factor for GP of cultivars from the Northeast, while the year of planting was the major factor affecting the stability of GPs in Huang-Huai summer and southern summer soybean. AMMI2(additive main effects and multiplicativeinteraction)-Biplot analysis showed that the GPs of soybean cultivars from the Northeast eco-region have a comparatively satisfactory environmental stability. Moreover, soybean cultivars with moderate GP/MG and stable environment adaptability in different eco-regions were identified based on the linear regression and AMMI analysis, which was important for the accurate classification of soybean MGs in future. Taken together, our results reflected the genetic diversity, geographical distribution and environmental stability of the Chinese soybean GP trait. Soybean cultivars with stable GP for various Chinese eco-regions would be beneficial for Chinese soybean genetic improvement, varietal introduction, exchange, and soybean breeding program for wide adaptability. 展开更多
关键词 SOYBEAN growth periods maturity group environmental stability
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Typhoon wind hazard model and estimation on return period of typhoon wind speed 被引量:1
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作者 Yunxia GUO Yijun HOU Peng QI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第2期420-436,共17页
Typhoons are one of the most serious natural disasters that occur annually on China’s southeast coast.A technique for analyzing the typhoon wind hazard was developed based on the empirical track model,and used to gen... Typhoons are one of the most serious natural disasters that occur annually on China’s southeast coast.A technique for analyzing the typhoon wind hazard was developed based on the empirical track model,and used to generate 1000-year virtual typhoons for Northwest Pacific basin.The influences of typhoon decay model,track model,and the extreme value distribution on the predicted extreme wind speed were investigated.We found that different typhoon decay models have least influence on the predicted extreme wind speed.Over most of the southeast coast of China,the predicted wind speed by the non-simplified empirical track model is larger than that from the simplified tracking model.The extreme wind speed predicted by different extreme value distribution is quite different.Four super typhoons Meranti(2016),Hato(2017),Mangkhut(2018)and Lekima(2019)were selected and the return periods of typhoon wind speeds along the China southeast coast were estimated in order to assess the typhoon wind hazard. 展开更多
关键词 TYPHOON empirical track model decay model extreme wind speed return period
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