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Syllabus in the Light of Keeping Pace with the Times
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作者 郝雁南 《Sino-US English Teaching》 2006年第8期42-44,共3页
Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates' English level, the availabl... Drawing up of syllabus plays a very important role in directing college English teaching. With the fast developing pace of the situation and the increasing requirements for undergraduates' English level, the available Syllabus is obviously far from satisfaction. This paper, from six perspectives, expounds the inadequacies and drawbacks of the Syllabus. It points out that college English teaching and the Syllabus need reform and should keep pace with the times. 展开更多
关键词 SYLLABUS inadequacy and drawback keep pace with the times
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Keeping Pace With the Times and Making In novation in a Pioneering Spirit
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作者 Staff Reporter Deng Fei 《International Understanding》 2003年第3期34-36,共3页
关键词 in keeping pace with the times and Making In novation in a Pioneering Spirit In
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Trends in the survival of patients with nasopharyngeal carcinoma between 1976 and 2005 in Sihui, China: a population-based study 被引量:12
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作者 Qing Liu Jin-Ou Chen +1 位作者 Qi-Hong Huang Yan-Hua Li 《Chinese Journal of Cancer》 SCIE CAS CSCD 2013年第6期325-333,共9页
Both the incidence a nd mortality of nasopharyngeal carcinoma(NPC) have decreased in Hong Kong and Taiwan but not in China's Mainland. The goal of this study was to analyze trends in NPC patient survival between 1... Both the incidence a nd mortality of nasopharyngeal carcinoma(NPC) have decreased in Hong Kong and Taiwan but not in China's Mainland. The goal of this study was to analyze trends in NPC patient survival between 1976 and 2005 in Sihui, an area of China's Mainland with a population at high risk for NPC. A total of 1,761 patients diagnosed with NPC between 1976 and 2005 according to the records of Sihui Cancer Registry were followed to the end of 2006. We determined their observed and relative survival rates and used Cox proportional hazards regression analysis to predict prognosis. Our results showed that the 5-year and 10-year observed survival rates of NPC patients in Sihui were 50.5% and 36.9% , respectively, and the median survival time was 5.1 years. The 5-year observed survival rate of NPC patients diagnosed after 2000 was 69.8%, significantly higher than that of patients diagnosed between 1976 and 1985 (42.5% ; P<0.001, relative risk=0.28). Similarly, the 5-year relative survival rate was 84.8% between 2000 and 2005 but 51.8% between 1976 and 1985. Besides date of diagnosis, other prognostic factors included patient sex and age and NPC clinical stage and histologic type. The relative risks of death from NPC were 0.76 [95% confidence interval (CI): 0.65-0.90] for female comparing to male and 1.28 (95% CI: 1.00-1.64) for WHO type I comparing to WHO types II and III. For the eldest age group and the latest clinical stage group, the relative risks were 2.22 (95% CI: 1.73-2.84) and 3.41 (95% CI: 2.34-4.49), respectively. Our results indicate that the survival of NPC patients in Sihui has significantly increased in recent years and this increase is not influenced by patient's sex, age, histologic type, and clinical stage. A reduction in mortality rate is expected in coming years. 展开更多
关键词 中国大陆地区 鼻咽癌 四会市 患者 人口 基础 世界卫生组织 NPC
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Hydrogen Energy in Shandong:Building on the Momentum and Joining the Trend of Our Times
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作者 Wen Ling 《Engineering》 SCIE EI 2021年第6期726-727,共2页
1.Introduction Hydrogen energy is one of the most promising clean energies in the world and can be widely used in transportation,the industrial sector,electricity,construction,and other fields.As a strategic and leadi... 1.Introduction Hydrogen energy is one of the most promising clean energies in the world and can be widely used in transportation,the industrial sector,electricity,construction,and other fields.As a strategic and leading emerging industry,hydrogen energy represents an important direction in future technological revolution and energy development.Major developed countries and regions such as the United States,Japan,the Republic of Korea. 展开更多
关键词 times SHANDONG trend
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Trend of the Times
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作者 ZHAO YANG 《China Today》 2023年第6期40-42,共3页
The rise of the Chinese economy and China’s cultural confidence is driving the popularity of brands rooted in the unique Chinese culture.LITERALLY meaning a national wave or national trend,Guochao denotes a new consu... The rise of the Chinese economy and China’s cultural confidence is driving the popularity of brands rooted in the unique Chinese culture.LITERALLY meaning a national wave or national trend,Guochao denotes a new consumer trend emerging in China in recent years.With the rise of the Chinese economy,domestic brands are embracing traditional cultural elements boosted by the Chinese pride in the achievements of the nation.Traditional culture has become a unique feature of Chinese brands going abroad and even foreign brands courting the Chinese market.From clothing and daily necessities to cell phones and cars。 展开更多
关键词 times driving trend
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Strengthening Exchanges and Cooperation in the Northeast Asia Region Follows the Trend of the Times——Sidelights of the 10^(th) Northeast Asia Youth Forum
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作者 Wen Desheng Bai Ruijun 《International Understanding》 2013年第4期33-35,共3页
The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seve... The 10thNortheast Asia Youth Forum,with the theme of China-ROK-Japan Youth Employment Guidance,sponsored by Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea was held in Seoul and Cheonan from August 12 to 17.Seventy five college students from 37 universities sent by China International Youth Exchange Center,Moral Re-Armament/Initiatives of Change(MRA/IC)-Korea and Japan Society attended the Forum.Lee Boksil,Vice-Minister of Ministry of 展开更多
关键词 Re Sidelights of the 10 Strengthening Exchanges and Cooperation in the Northeast Asia Region Follows the trend of the times TH Northeast Asia Youth Forum Asia
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Changing trends of clinicopathologic features and survival duration after surgery for gastric cancer in Northeast China 被引量:2
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作者 Zhao Zhai Zi-Yu Zhu +11 位作者 Xi-Liang Cong Bang-Ling Han Jia-Liang Gao Xin Yin Yu Zhang Sheng-Han Lou Tian-Yi Fang Yi-Min Wang Chun-Feng Li Xue-Feng Yu Yan Ma Ying-Wei Xue 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2020年第10期1119-1132,共14页
BACKGROUND Through analyzing the data from a single institution in Northeast China,this study revealed the possible clinicopathologic characteristics that influence the prognosis of patients with gastric cancer(GC).AI... BACKGROUND Through analyzing the data from a single institution in Northeast China,this study revealed the possible clinicopathologic characteristics that influence the prognosis of patients with gastric cancer(GC).AIM To evaluate the changing trends of clinicopathologic features and survival duration after surgery in patients with GC in Northeast China,which is a highprevalence area of GC.METHODS The study analyzed the difference in clinicopathologic features and survival duration after surgery of 5887 patients who were histologically diagnosed with GC at the Harbin Medical University Cancer Hospital.The study mainly analyzed the data in three periods,2000 to 2004(Phase 1),2005 to 2009(Phase 2),and 2010 to 2014(Phase 3).RESULTS Over time,the postoperative survival rate significantly increased from 2000 to 2014.In the past 15 years,compared with Phases 1 and 2,the tumor size was smaller in Phase 3(P<0.001),but the proportion of high-medium differentiated tumors increased(P<0.001).The proportion of early GC gradually increased from 3.9%to 14.4%(P<0.001).A surprising improvement was observed in the mean number of retrieved lymph nodes,ranging from 11.4 to 27.5(P<0.001).The overall 5-year survival rate increased from 24%in Phase 1 to 43.8%in Phase 3.Through multivariate analysis,it was found that age,tumor size,histologic type,tumor-node-metastasis stage,depth of invasion,lymph node metastasis,surgical approach,local infiltration,radical extent,number of retrieved lymph nodes,and age group were independent risk factors that influenced the prognosis of patients with GC.CONCLUSION The clinical features of GC in Northeast China changed during the observation period.The increasing detection of early GC and more standardized surgical treatment effectively prolonged lifetimes. 展开更多
关键词 Gastric cancer Clinicopathologic features SURVIVAL Time trends EPIDEMIOLOGY GASTRECTOMY
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Conforming to the Trend at An Appropriate Time——My Thoughts on the Building of the Silk Road Economic Belt 被引量:2
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作者 Zhang Zhiming Pu Zhuangyi 《International Understanding》 2013年第4期6-8,共3页
During his state visit to Kazakhstan this September,President Xi Jinping made a concrete proposal to build a Silk Road Economic Belt(SREB for short in the following paragraphs)from the aspects of policy communication,... During his state visit to Kazakhstan this September,President Xi Jinping made a concrete proposal to build a Silk Road Economic Belt(SREB for short in the following paragraphs)from the aspects of policy communication,road connectivity, 展开更多
关键词 My Thoughts on the Building of the Silk Road Economic Belt Conforming to the trend at An Appropriate Time
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The Trend and Fluctuation of Historical Floods in the Middle Reaches of the Yangtze River
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作者 Wu Yi-jin +2 位作者 William A.Gough 《Wuhan University Journal of Natural Sciences》 CAS 2003年第01A期91-94,共4页
The middle reaches of the Yangtze River are the worst flood area of the whole basin. To study the variation regulation of the fl oods in this area over a long historical period assure improvement in prediction s of ... The middle reaches of the Yangtze River are the worst flood area of the whole basin. To study the variation regulation of the fl oods in this area over a long historical period assure improvement in prediction s of floods in the region. The trend of flood occurred frequency has close relat ionship with human activities near the river. By using statistics analysis, the fluctuations for the time series of floods since 1525 are studied. The results show that the main cycle of flood variation can be identified obviously the per iod of 2, 8 and 40 years with exceeding the level of confidence 0.03. 展开更多
关键词 floods trend and fluctuation Yangtze river hi storical time
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Space-time analysis of the changing patterns of population pressure on the ecological environment in China 被引量:1
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作者 Dongqi Sun Jinliang Jiang +2 位作者 Jianbin Xu Liang Zhou Yi Hu 《Chinese Journal of Population,Resources and Environment》 2015年第4期341-348,共8页
This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrat... This paper examines the temporal change and spatial variation of population pressure on the ecological environment in China.We have collected sufficient data from the statistical yearbooks of 31 provincial administrative areas in 1990,1995,2000,2005,and 2010.Using a geographic information system(GIS) and relevant models,we analyzed the trend of the population pressure on ecological environment and the change of the gravity center of ecological environment quality.We conclude that:(1) generally,population pressure on the ecological environment in China was becoming higher during1990-2010,especially in some areas where the population and environment were in serious imbalance and the ecological environment experienced severe pollution;(2) during a certain period,population pressure on the ecological environment was becoming lower in some areas,but the ecological environment was getting worse;(3) the areas with super-high population pressure on the ecological environment were Beijing,Tianjin,and Shanghai;(4) the gravity center of population pressure on the ecological environment and the center of ecological environment quality move differently during the study time period,but the general trend was similar- both of them were moving from west to east.Based on the analysis,this paper also provides some policy suggestions on the control of ecological environment quality. 展开更多
关键词 Chinese POPULATION ECO-ENVIRONMENT ECO-ENVIRONMENTAL pressure CHANGING trend Space-TIME analysis
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Research on the Developmental Trend of Data Journalism under the Background and Time of Big Data
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作者 Hui Zhi 《International Journal of Technology Management》 2016年第1期42-44,共3页
In this paper, we conduct research on the developmental trend of the data journalism under the current background and the time of big data. Big data is not only a concept, but also a description of a state of society... In this paper, we conduct research on the developmental trend of the data journalism under the current background and the time of big data. Big data is not only a concept, but also a description of a state of society: in the era of the big data, data become important social resources and production data, the news media is no exception. In the time of the data had not been so seriously, the core of the news resources is a reporter on the scene to get first-hand material, is based on the reporter can see, smell, feel the fact description, data is often only a supplementary role. However, in today' s era of big data, although the scene is also very important, but based on the various aspects of data mining and analysis and the depth of the formation of information has become more and more important. Our research proposes the novel paradigm for the issues that is meaningful. 展开更多
关键词 Big Data Developmental trend Data Journalism Contemporary Era and Time.
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Analysis of the Main Factors Influencing Food Production in China Based on Time Series Trend Chart
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作者 Shuangjin WANG Jianying LI 《Asian Agricultural Research》 2014年第6期37-42,共6页
Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effectiv... Based on the annual sample data on food production in China since the reform and opening up,we select 8 main factors influencing the total food production( growing area,application rate of chemical fertilizer,effective irrigation area,the affected area,total machinery power,food production cost index,food production price index,financial funds for supporting agriculture,farmers and countryside),and put them into categories of material input,resources and environment,and policy factors. Using the factor analysis,we carry out the multi-angle analysis of these typical influencing factors one by one through the time series trend chart. It is found that application rate of chemical fertilizer,the growing area of food crops and drought-affected area become the key factors affecting food production. On this basis,we set forth the corresponding recommendations for improving the comprehensive food production capacity. 展开更多
关键词 FOOD PRODUCTION Influencing FACTORS TIME SERIES TR
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The epidemiology of colorectal cancer in China 被引量:13
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作者 Rongshou Zheng Hongmei Zeng +6 位作者 Siwei Zhang Xiuying Gu Kexin Sun Changfa Xia Zhixun Yang He Li Wanqing Chen 《Global Health Journal》 2018年第3期8-20,共13页
Objective:Colorectal cancer(CRC)is one of the most common cancers and the major cause of cancer death in China.The aim of this study was to estimate the burden of CRC in China.Materials and methods:Data from the Natio... Objective:Colorectal cancer(CRC)is one of the most common cancers and the major cause of cancer death in China.The aim of this study was to estimate the burden of CRC in China.Materials and methods:Data from the National Cancer Center(NCC)of China was used and stratified by area(urban/rural),sex(male/female)for analyzing the age-speci c incidence and mortality rates.Time trend of colorectal cancer was calculated based on the 22 high-quality cancer registries in China.National new cases and deaths of colorectal cancer were estimated using age-speci c rates multiplied by the corresponding national population in 2014.The Chinese population in 2000 and Segi’s world population were used to calculate age-standardized rates of colorectal cancer in China.Results:Overall,370,400 new colorectal cancer cases and 179,600 deaths were estimated in China in 2014,with about 214,100 new cases in men and 156,300 in women.Meanwhile,104,000 deaths cases of colorectal cancer were men and 75,600 deaths were women,which accounted for 9.74%and 7.82%of all cancer incidence and deaths in China,separately.Relatively higher incidence and mortality was observed in urban areas of China.And the Eastern areas of China showed the highest incidence and mortality.The age-standardized incidence and mortality rate of colorectal cancer has increased by about 1.9%per year for incidence and about 0.9%per year for mortality rate from 2000 to 2014.Conclusion:With gradually higher incidence and mortality rate in the past 15 years,colorectal cancer became a major challenge to China’s public health.E ective control strategies are needed in China. 展开更多
关键词 COLORECTAL cancer time trendS INCIDENCE MORTALITY China
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Analysis of stochastic characteristics of the Benue River flow process 被引量:1
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作者 Martins Y. OTACHE Mohammad BAKIR 李致家 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第2期142-151,共10页
Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity. The streamflow process is investigated for trend, non-stationarity and seasonality for a time period of... Stochastic characteristics of the Benue River streamflow process are examined under conditions of data austerity. The streamflow process is investigated for trend, non-stationarity and seasonality for a time period of 26 years. Results of trend analyses with Mann-Kendall test show that there is no trend in the annual mean discharges. Monthly flow series examined with seasonal Kendall test indicate the presence of positive change in the trend for some months, especially the months of August, January, and February. For the stationarity test, daily and monthly flow series appear to be stationary whereas at 1%, 5%, and 10% significant levels, the stationarity alternative hypothesis is rejected for the annual flow series. Though monthly flow appears to be stationary going by this test, because of high seasonality, it could be said to exhibit periodic stationarity based on the seasonality analysis. The following conclusions are drawn: (1) There is seasonality in both the mean and variance with unimodal distribution. (2) Days with high mean also have high variance. (3) Skewness coefficients for the months within the dry season period are greater than those of the wet season period, and seasonal autocorrelations for streamflow during dry season are generally larger than those of the wet season. Precisely, they are significantly different for most of the months. (4) The autocorrelation functions estimated "over time" are greater in the absolute value for data that have not been deseasonalised but were initially normalised by logarithmic transformation only, while autocorrelation functions for i = 1, 2 365 estimated "over realisations" have their coefficients significantly different from other coefficients. 展开更多
关键词 trend stationarity SEASONALITY over time over realisation STOCHASTIC SKEWNESS
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Analysis on the Climate Characteristics of Thunderstorm in Fujian Province during 1960-2007 被引量:1
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作者 LIN Xiu-fang1,YOU Li-hang2,WEN Ming-zhang1 1.Fujian Climate Center,Fuzhou 350001,China 2.Meteorological Service Center in Fujian Province,Fuzhou 350001,China 《Meteorological and Environmental Research》 CAS 2011年第3期21-24,共4页
[Objective] The research aimed to study the activity characteristics and climate rule of thunderstorm in Fujian Province.[Method] Based on the daily thunderstorm data in 67 meteorological stations of Fujian Province d... [Objective] The research aimed to study the activity characteristics and climate rule of thunderstorm in Fujian Province.[Method] Based on the daily thunderstorm data in 67 meteorological stations of Fujian Province during 1960-2007,the spatial and temporal distribution characteristics of thunderstorm in Fujian Province were analyzed by using the climate tendency rate,the trend coefficient and so on.[Result] The distribution of thunderstorm days showed the northeast-southwest direction and increased gradually from the coast to the inland in Fujian Province during 1960-2007.The high value zone was in Longyan,and the thunderstorm days in the coastal islands were the fewest.The thunderstorm days had the obvious decrease trend in Fujian Province in 48 years.The decrease speeds in the central coastal area and most of inland mountain area were 3.5 and 4.5 d/10 a.The decrease speed was 5.5 d/10 a in the north of Ningde,the east of Sanming and some areas in Nanping.The trend coefficient variation of thunderstorm days had the obvious regional characteristic.Especially the decrease trend in the inland mountain area was more obvious than that in the coast.The decrease of thunderstorm day trend coefficient in the north of Nanping was the most,and the trend coefficient was-0.65.But the decrease trend in the central coastal area wasn’t obvious,and the coefficient was only-0.15.The thunderstorm day had the obvious seasonal variation.The multi-occurrence period of thunderstorm was during March-september and reached the maximum value in August.Started from September,the thunderstorm quickly decreased.From October to February in next year,the thunderstorm happened seldom.The average first thunderstorm date in the northwest area was earlier than that in the southeast area.The difference of average final thunderstorm date in the north and south areas wasn’t big.For the first thunderstorm date in the north and west of Fujian was early,and the final thunderstorm date was later,the thunderstorm activity time in the whole year was longer than that in the coast.They differed by nearly one month.[Conclusion] The research provided the scientific basis for the climate feasibility demonstration of major project items,provided the theory basis about the weather climate aspect for the thunder prevention and disaster reduction,and also laid the foundation for further studying the formation mechanism of thunderstorm in Fujian. 展开更多
关键词 THUNDERSTORM Time and space characteristics trend coefficient Fujian Province China
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Trend and Periodicity of Temperature Time Series in Ontario 被引量:1
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作者 Syed Imran Ahmed Ramesh Rudra +1 位作者 Trevor Dickinson Motahir Ahmed 《American Journal of Climate Change》 2014年第3期272-288,共17页
The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyse... The trends and periodicities in the annual and seasonal temperature time series at fifteen weather stations within Ontario Great Lakes Basins have been analyzed, for the period 1941-2005, using the statistical analyses (Fourier series analysis, t-test, and Mann-Kendall test). The stations were spatially divided into three regions: northwest (NW), southwest (SW), and southeast (SE) to evaluate spatial variability in temperature. The results of the study reveal that the annual maximum mean temperature showed increasing trend for NW, and mixed trends for SW and SE regions. The variability was found to be more for northern stations as compared to southern stations for annual extreme minimum temperature. In addition, the trend slope per 100 years for the average annual extreme minimum temperature increased within the range of -0.8°C (Stratford) to 15°C (Porcupine). The seasonal analysis demonstrated that extreme maximum temperature has an increasing trend and maximum mean temperature has a decreasing trend during summer and winter. The extreme minimum temperature for winter illustrated an increasing trend (90%) with 22% statistically significant for NW region. For the SW region, the trend is also increasing (80%) for most of the temperature variables and 25% of temperature data were significantly increased in the SW region. The SE region stations showed overall very clear increasing trends (95%) for all the temperature variables. The data also showed that 47% of data were statistically significant in the SE region. The analysis of variance accounted for by trend, significant periodicities, and random component show that the pattern is similar for the percent of variance accounted for periodicities, and random component contribute dominantly for the four temperature variables and frost free days (FFD) for all three regions. Overall, the study reveals that the extreme minimum temperature is increasing annually and seasonally, with statistically significant at many stations. 展开更多
关键词 Time Series trend PERIODICITY MANN-KENDALL Test T-TEST FROST Free Days
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Research on trend prediction of component stock in fuzzy time series based on deep forest 被引量:1
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作者 Peng Li Hengwen Gu +1 位作者 Lili Yin Benling Li 《CAAI Transactions on Intelligence Technology》 SCIE EI 2022年第4期617-626,共10页
With the continuous development of machine learning and the increasing complexity of financial data analysis,it is more popular to use models in the field of machine learning to solve the hot and difficult problems in... With the continuous development of machine learning and the increasing complexity of financial data analysis,it is more popular to use models in the field of machine learning to solve the hot and difficult problems in the financial industry.To improve the effectiveness of stock trend prediction and solve the problems in time series data processing,this paper combines the fuzzy affiliation function with stock-related technical indicators to obtain nominal data that can widely reflect the constituent stocks in the case of time series changes by analysing the S&P 500 index.Meanwhile,in order to optimise the current machine learning algorithm in which the setting and adjustment of hyperparameters rely too much on empirical knowledge,this paper combines the deep forest model to train the stock data separately.The experimental results show that(1)the accuracy of the extreme random forest and the accuracy of the multi-grain cascade forest are both higher than that of the gated recurrent unit(GRU)model when the un-fuzzy index-adjusted dataset is used as features for input,(2)the accuracy of the extreme random forest and the accuracy of the multigranular cascade forest are improved by using the fuzzy index-adjusted dataset as features for input,(3)the accuracy of the fuzzy index-adjusted dataset as features for inputting the extreme random forest is improved by 18.89% compared to that of the un-fuzzy index-adjusted dataset as features for inputting the extreme random forest and(4)the average accuracy of the fuzzy index-adjusted dataset as features for inputting multi-grain cascade forest increased by 5.67%. 展开更多
关键词 deep forest fuzzy membership function price pattern time series trend forecast
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Winter sea ice albedo variations in the Bohai Sea of China 被引量:2
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作者 ZHENG Jiajia KE Changqing SHAO Zhude 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期56-63,共8页
Sea ice conditions in the Bohai Sea of China are sensitive to large-scale climatic variations. On the basis of CLARA-A1-SAL data, the albedo variations are examined in space and time in the winter(December, January a... Sea ice conditions in the Bohai Sea of China are sensitive to large-scale climatic variations. On the basis of CLARA-A1-SAL data, the albedo variations are examined in space and time in the winter(December, January and February) from 1992 to 2008 in the Bohai Sea sea ice region. Time series data of the sea ice concentration(SIC), the sea ice extent(SIE) and the sea surface temperature(SST) are used to analyze their relationship with the albedo. The sea ice albedo changed in volatility appears along with time, the trend is not obvious and increases very slightly during the study period at a rate of 0.388% per decade over the Bohai Sea sea ice region.The interannual variation is between 9.93% and 14.50%, and the average albedo is 11.79%. The sea ice albedo in years with heavy sea ice coverage, 1999, 2000 and 2005, is significantly higher than that in other years; in years with light sea ice coverage, 1994, 1998, 2001 and 2006, has low values. For the monthly albedo, the increasing trend(at a rate of 0.988% per decade) in December is distinctly higher than that in January and February. The mean albedo in January(12.90%) is also distinctly higher than that in the other two months. The albedo is significantly positively correlated with the SIC and is significantly negatively correlated with the SST(significance level 90%). 展开更多
关键词 Bohai Sea sea ice region albedo variations in space and time trend sea ice concentration sea ice extent sea surface temperature
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Piecewise linear representation of time series based on mean trend in sliding window
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作者 袁同雨 吴绍春 +3 位作者 张建 谷蓉蓉 陈高照 徐勇泉 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期473-478,共6页
Seismic data show some important characteristics, such as big volume and strong timeliness. Specific to the time series data of earthquake precursory observations, a piecewise linear representation based on the slidin... Seismic data show some important characteristics, such as big volume and strong timeliness. Specific to the time series data of earthquake precursory observations, a piecewise linear representation based on the sliding window mean value (PLR_MTSW) algorithm is proposed. With this algorithm, the mutation points can be identified accurately according to the rate Of mean value change, while the main features of time series are maintained well. This algorithm can also smooth the noise and improve the compression accuracy with sliding window. Meanwhile the local extreme points can be identified effectively according to the change of mean value trend within window. 展开更多
关键词 earthquake precursor time series changing rate trend
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Characterizing the Urban Temperature Trend Using Seasonal Unit Root Analysis:Hong Kong from 1970 to 2015
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作者 Wai-Ming TO Tat-Wai YU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第12期1376-1385,共10页
This paper explores urban temperature in Hong Kong using long-term time series. In particular, the characterization of the urban temperature trend was investigated using the seasonal unit root analysis of monthly mean... This paper explores urban temperature in Hong Kong using long-term time series. In particular, the characterization of the urban temperature trend was investigated using the seasonal unit root analysis of monthly mean air temperature data over the period January 1970 to December 2013. The seasonal unit root test makes it possible to determine the stochastic trend of monthly temperatures using an autoregressive model. The test results showed that mean air temperature has increased by 0.169~ C (10 yr) - 1 over the past four decades. The model of monthly temperature obtained from the seasonal unit root analysis was able to explain 95.9% of the variance in the measured monthly data -- much higher than the variance explained by the ordinary least-squares model using annual mean air temperature data and other studies alike. The model accurately predicted monthly mean air temperatures between January 2014 and December 2015 with a root-mean-square percentage error of 4.2%. The correlation between the predicted and the measured monthly mean air temperatures was 0.989. By analyzing the monthly air temperatures recorded at an urban site and a rural site, it was found that the urban heat island effect led to the urban site being on average 0.865~C warmer than the rural site over the past two decades. Besides, the results of correlation analysis showed that the increase in annual mean air temperature was significantly associated with the increase in population, gross domestic product, urban land use, and energy use, with the R2 values ranging from 0.37 to 0.43. 展开更多
关键词 urban temperature trend urban heat island effect seasonal unit root tests long-term time series
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