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广播收听率“月变化”对节目调整的必要性
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作者 樊华 樊辉 《科技传播》 2015年第12期157 142-,142,共2页
广播收听率是广播电台分析听众收听情况的重要参考数据,其"月变化"指标则以一段中等长度时间段内收听率波动情况反映了节目质量与效果。本文介绍了广播收听率存在意义,分析了广播收听率"月变化"对节目调整的必要性... 广播收听率是广播电台分析听众收听情况的重要参考数据,其"月变化"指标则以一段中等长度时间段内收听率波动情况反映了节目质量与效果。本文介绍了广播收听率存在意义,分析了广播收听率"月变化"对节目调整的必要性,以期为广大媒体从业人员提供参考。 展开更多
关键词 广播 收听率 “月变化” 节目调整 必要性
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Annual and Monthly Variations in Litter Macronutrients of Three Subalpine Forests in Western China 被引量:49
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作者 YANG Wan-Qin WANG Kai-Yun +1 位作者 S. KELLOMAKI ZHANG Jian 《Pedosphere》 SCIE CAS CSCD 2006年第6期788-798,共11页
Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) ... Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter (LL) than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems. 展开更多
关键词 LITTERFALL macronutrient return monthly variation nutrient concentration subalpine forest
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Monthly Variation in Crustacean Assemblage(Decapod and Stomatopod) and Its Relationships with Environmental Variables in Laizhou Bay,China 被引量:5
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作者 WU Qiang WANG Jun +2 位作者 ZHANG Bo CHEN Ruisheng JIN Xianshi 《Journal of Ocean University of China》 SCIE CAS 2016年第2期370-378,共9页
In this study,we investigated the community structure of crustaceans(decapod and stomatopod) inhabiting the sandy mud bottoms of Laizhou Bay(northeastern China) monthly from May 2011 to April 2012.Investigation was st... In this study,we investigated the community structure of crustaceans(decapod and stomatopod) inhabiting the sandy mud bottoms of Laizhou Bay(northeastern China) monthly from May 2011 to April 2012.Investigation was stopped from December 2011 to February 2012 because of the extreme weather and sea ice.A total of 205,057 specimens belonging to 31 species(shrimp,15;crab,15;and stomatopod,1) were collected in 148 hauls.From 2011 to 2012,Oratosquilla oratoria was the dominant biomass species(47.80%),followed by Charybdis japonica(15.49%),Alpheus japonicas(12.61%),Portunus trituberculatus(6.46%),and Crangon spp.(4.19%).Crangon spp.was the most dominant species by individual(32.55%).O.oratoria was the most-frequently encountered species(81.76%),followed by Palaemon gravieri(70.95%),C.japonica(65.54%),A.japonicas(62.16%),and P.trituberculatus(54.73%).The biomass density increased from August to September 2011 and decreased from March 2012 to April 2012.The dynamics of the ecological indices evolve in a similar manner,with high values of diversity and evenness and rich species from May to June 2011 and low values from September to October 2011.O.oratoria,C.japonica,and P.trituberculatus differed by biomass data between groups I(samples obtained from September to October 2011) and II(samples in other months).These species contributed more than 70% to the similarity of the crustacean community structure.Furthermore,the subsets of environmental variables that best matched the crustacean-assemblage structure were as follows:water depth(WD) in summer(June to August);sea surface temperature(SST),dissolved oxygen(DO),and WD in autumn(September to November);and DO,salinity,and WD in spring(March to May).The calculated correlation coefficients and significance level were higher in the period of July to August 2011 than in other months.Comparing 2011 to 2012 with 1982 to 1983,the species composition remained stable.However,the dominant species changed significantly.High value and large species,such as F.chinensis,P.trituberculatus,and T.curvirostris,have been replaced by low value and small species(i.e.,Crangon spp.,P.gravieri,and C.japonica). 展开更多
关键词 monthly variation crustacean-assemblage structure environmental variable Laizhou Bay
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Change in the body temperature of healthy term infant over the first 72 hours of life 被引量:5
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作者 李萌霞 孙革 NEUBAUERHenning 《Journal of Zhejiang University Science》 CSCD 2004年第4期486-493,共8页
Objective: To determine the range of body temperature in a group of healthy Chinese term neonates over the first 72 hours of life and to assess the influence of body weight, gestational age and route of delivery. Meth... Objective: To determine the range of body temperature in a group of healthy Chinese term neonates over the first 72 hours of life and to assess the influence of body weight, gestational age and route of delivery. Method: All 200 consecutive cases of neonates delivered at our hospital from March to August 2001 were included in this retrospective study. Temperatures were measured immediately after delivery, after 30 minutes, 1 hour, 2 hours, 8 hours and 15 hours and on the 2nd and 3rd day. Axillary temperatures ranging from 36.5 篊 to 37 篊 were regarded as normal. No cases of maternal fever or systemic infection of the newborns were discovered. All infants were discharged in good general condition. Results: The mean rectal temperature at birth was 37.19 篊. The lowest average temperature was reached at 1 hour after delivery (36.54 篊) with a significant difference between natural delivery (36.48 篊) and section (36.59 篊) (P<0.05). Temperature subsequently rose to 36.70 篊 at 8 hours and 36.78 篊 at 15 hours (P<0.05). Hypothermia was seen in 51.8% and hypothermia in 42.5% of the patients. On the 3rd day after delivery, 96% of all temperatures were in the normal range. A significant relation was found between hypothermia and both low birth weight (P<0.001) and low gestational age (P<0.05). Conclusion: The ref-erence range presently used did not include all physiological temperatures in the first 72 hours of life. Considering other factors, such as birth weight, route of delivery, gestational age and body temperature on the 2nd and 3rd day of life, may help to correctly assess the significance of temperatures beyond the reference range. 展开更多
关键词 Body temperature Term infant Rectal temperature Axillary temperature
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THE INTERANNUAL AND DECADAL VARIABILITY OF PRECIPITATION FOR YUNNAN PROVINCE IN RAINY SEASON AND ITS RELATIONSHIP WITH TROPICAL UPPER LAYER TEAT CONTENT
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作者 郑春怡 黄菲 普贵明 《Journal of Tropical Meteorology》 SCIE 2003年第2期164-172,共9页
Based on the monthly precipitation data of 126 observation stations from 1961 to 2000 in Yunnan Province, the interannual and decadal variability of precipitation in rainy seasons are studied by using wavelet analysis... Based on the monthly precipitation data of 126 observation stations from 1961 to 2000 in Yunnan Province, the interannual and decadal variability of precipitation in rainy seasons are studied by using wavelet analysis. It is shown that there is a 2-6 year oscillation at the interannual time scales and a quasi-30 year oscillation at the decadal time scales. These periodic oscillations relate to the distribution of tropical heat content. When the precipitation is much more (less) than normal, the upper seawater is colder (warmer) in almost all the tropical Indian Ocean, and warmer (colder) in the western Pacific as well as colder (warmer) in the eastern Pacific. The key areas of the anomaly heat content distribution that have significant correlation to the Yunnan precipitation in rainy season are in the southern hemispheric Indian Ocean with a dipole pattern in the winter as well as in the deep basin of the South China Sea (SCS) before the Yunnan rainy season begins. Therefore, the anomalous distributions of the heat content in the southern Indian Ocean and the SCS In winter are good indicators for predicting drought or flood in Yunnan Province in the following rainy season. 展开更多
关键词 rainy season precipitation in Yunnan Province interannual and decadal variability tropical oceans heat content
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Summer Monsoon and Annual Variability of Sea Surface Slope and Their Effects on Alongshore Current near Qingdao
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作者 蒲书箴 程军 +3 位作者 张义钧 石强 骆敬新 范文静 《Marine Science Bulletin》 CAS 2004年第2期1-8,共8页
Based on the monthly mean sea level data obtained from 3 years’ (1999— 2001) tide-gauge measurements, the annual variability of the sea level near Qingdao and Jiaozhou Bay is studied and discussed in this paper. Res... Based on the monthly mean sea level data obtained from 3 years’ (1999— 2001) tide-gauge measurements, the annual variability of the sea level near Qingdao and Jiaozhou Bay is studied and discussed in this paper. Results show that the sea surface height at all the tide gauges becomes higher in summer than that in winter, with an obvious seasonal variability. Furthermore the sea surface height measured at a short distance outside the bay is lower than that in the bay, showing a sea surface slope downward from north to south. The reasons for the formation of the slope are explained as well. The dynamic action of the summer monsoon and the sea surface slope, and their effects on the monthly mean current are studied by means of dynamics principles. The importance of the summer monsoon and the pressure gradient generated by the sea surface slope, with their effects on the alongshore current, is pointed out and emphasized in this paper. 展开更多
关键词 Jiaozhou Bay sea surface slope MONSOON alongshore current
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THE ANALYSIS ON THE STATISTICAL CHARACTER OF QUIKSCAT SCATTEROMETER WINDS AND STRONG WIND FREQUENCY USING REMOTE SENSOR DATA FROM QUIKSCAT
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作者 刘春霞 何溪澄 《Journal of Tropical Meteorology》 SCIE 2003年第2期113-123,共11页
The statistical character of QuikSCAT scatterometer winds is showed. And Monthly change and special distribution character of strong wind frequency and monthly wind fields in South China Sea is analyzed. It is shown i... The statistical character of QuikSCAT scatterometer winds is showed. And Monthly change and special distribution character of strong wind frequency and monthly wind fields in South China Sea is analyzed. It is shown in the result that the QuikSCAT scatterometer winds can be relied upon for the South China Sea; two winds, one the wintertime northeasterly and the other summertime southwesterly. The northeasterly centers at the Bashi Strait and Taiwam Strait and its secondary center and the maximum center of the southwesterly are in the central and southern South China Sea. 展开更多
关键词 QuikSCAT scatterometer winds strong wind frequency wind fields
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MULTI-TIMESCALE VARIATIONS OF SOMALI JET AND ITS RELATION WITH PRECIPITATION IN CHINA
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作者 代玮 肖子牛 《Journal of Tropical Meteorology》 SCIE 2015年第2期185-193,共9页
Based on the ERA reanalysis winds data, the multi-time scale variations of Somali jet are analyzed synthetically. The jet's influences on rainfall in China on interannual, interdecadal and sub-monthly scales are a... Based on the ERA reanalysis winds data, the multi-time scale variations of Somali jet are analyzed synthetically. The jet's influences on rainfall in China on interannual, interdecadal and sub-monthly scales are also studied using correlation and composite analyses. The results demonstrate that the interdecadal variations of the jet are significant.The Somali jet became weaker in the 1960 s and became the weakest in the early 1970 s before enhancing slowly in the late 1970 s. Moreover, the relation between the Somali jet and summer precipitation in China is close, but varies on different timescales. Preliminary analysis shows that the intensity variations in May and June during the early days of establishment are well correlated with summer precipitation in China. The Somali jet intensity on the interdecadal scale is closely related with interdecadal variations of the precipitation in China. Regardless of leading or contemporaneous correlation, the correlations between the Somali jet intensity and the rainfall in northern and southern China show obvious interdecadal variations. Moreover, the link between the anomalies of the jet intensity in May-August and precipitation evolution on synoptic scale in China is further studied. China has more rainfall with positive anomalies of the Somali jet but less rainfall with negative anomalies during the active period of the jet. The influence of positive Somali jet anomalies on China precipitation is more evident. 展开更多
关键词 multi-timescale variations Somali jet intensity precipitation in China
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INTENSITY INDEX OF SOUTH CHINA SEA MONSOON AND ITS VARIATION CHARACTERISTICS 被引量:2
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作者 吴尚森 梁建茵 《Journal of Tropical Meteorology》 SCIE 2002年第1期1-9,共9页
According to the basic characteristics of the activities of summer monsoon in the South China Sea, a standardized index, sI, has been designed that integrates a dynamic factor (southwesterly component) and a thermodyn... According to the basic characteristics of the activities of summer monsoon in the South China Sea, a standardized index, sI, has been designed that integrates a dynamic factor (southwesterly component) and a thermodynamic factor (OLR) for the indication of summer monsoon in the South China Sea. With the index determined for individual months of June, July and August and the entire summertime from 1975 to 1999, specific months and years are indicated that are either strong or weak in monsoon intensity. The variation is studied for the patterns and sI抯 relationship is revealed with the onset of summer monsoon and the precipitation in Guangdong province and China. The results show that there are quasi-10 and quasi-3-4 year cycles in the interannual variation of the monsoon over the past 25 years. When it has an early (late) onset, the summer monsoon is usually strong (weak). In the strong (weak) monsoon years, precipitation tends to be more (less) in the first raining season of the year but normal or less (normal) in the second, in the province, but it would be more (less) in northeastern China and most parts of the northern China and south of the lower reaches of the Changjiang River and less (more) in the middle and lower reaches of the river, western part of northern China and western China. 展开更多
关键词 South China Sea summer monsoon intensity index variation characteristics
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INDEX OF DIRECTION CHANGE OF ZONALLY AVERAGED WIND AND CHANGE OF SEASON
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作者 朱敏 徐建霞 张铭 《Journal of Tropical Meteorology》 SCIE 2011年第2期128-135,共8页
In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and season... In this paper, a Wind Direction Change Index (WI), which can describe four-dimensional spatiotemporal changes of the atmospheric circulation objectively and quantitatively, is defined to study its evolution and seasonal variation. The first four modes can be obtained by EOF expansion of the zonally averaged WI. The first mode reveals the basic spatial distribution of the annually averaged WI. The second mode reflects the quasi-harmonic parts of the WI deviations. Tropical, subtropical and extratropical monsoon areas can be clearly reflected by this mode. The third mode reflects the non-harmonic parts of the WI deviations. It shows the so-called February reverse in stratospheric atmosphere as well as the asymmetric seasonal changes from spring to fall and from fall to spring due to both the land-sea distribution contrast between the Northern and Southern Hemispheres and the nonlinear effect of atmospheric and ocean fluids. The fourth mode reveals the northward advancing of the global reversed wind fields from spring to summer and their southward withdrawal from summer to autumn. 展开更多
关键词 Wind Direction Change Index (WI) Empirical Orthogonal Function (EOF) four-dimensional space-time changes February stratospheric reverse
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Sub seasonal variations of weak stratospheric polar vortex in December and its impact on Eurasian air temperature 被引量:1
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作者 PENG Cheng FAN Ke DAI Haixia 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期369-375,共7页
Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar... Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar region.After the onset of a December WPV event,the dynamic processes influencing Eurasian temperature can be split into two separate periods.Period I(lag of 0-25 days)is referred to as the stratosphere-troposphere interactions period,as it is mainly characterized by stratospheric signals propagating downwards.In Period I,a stratospheric negative Northern Annular Mode(NAM)pattern associated with the WPV propagates downwards,inducing a negative NAM in the troposphere.The anomalous low centers over the Mediterranean and North Pacific bring cold advection to northern Eurasia,resulting in a north-cold-south-warm dipole pattern over Eurasia.The zero line between negative and positive temperature anomalies moves southwards during days 5-20.Stratospheric cold anomalies at midlatitudes propagate downwards to high latitudes in the troposphere and contribute to the dipole structure.During PeriodⅡ(lag of 25-40 days),as downward signals from the stratosphere have vanished,the dynamic processes mainly take place within the troposphere.Specifically,a wave train is initiated from the North Atlantic region to northern Europe.The propagation of wave activity flux intensifies a cyclonic anomaly over northern Europe,which brings cold advection to Scandinavia and warm advection to central Asia.Therefore,a northwest-cold-southeast-warm dipole structure occupies Eurasia and migrates southeastwards during this period. 展开更多
关键词 Stratospheric polar vortex weak stratospheric polar vortex events in December subseasonal variability stratosphere-troposphere interaction winter Eurasian air temperature(0-40 days)
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Effects of carbohydrate supplements on exercise-induced menstrual dysfunction and ovarian subcellular structural changes in rats
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作者 Can Zhao Xiao-Li Liu +3 位作者 Run-Xiao Hong He Li Rena Li Ren-Wei Wang 《Journal of Sport and Health Science》 SCIE 2014年第3期189-195,共7页
Background: Exercise-associated menstrual dysfunction (EAMD) is a common health problem in female athletes as a part of female athlete triad (FAT), a condition related to low energy availability. In this study, w... Background: Exercise-associated menstrual dysfunction (EAMD) is a common health problem in female athletes as a part of female athlete triad (FAT), a condition related to low energy availability. In this study, we explored the possibility that carbohydrate supplements can improve the status of EAMD and prevent exercise-induced ovarian injury in a FAT rat model. This research aimed to provide experimental evidence with regard to the relationship of energy intervention and EAMD. Methods: Forty-five female Sprague-Dawley rats (2 months old) were randomly divided into five experimental groups: control group (C), 9-week exercise as model for EAMD (E), post-EAMD recovery group (R), oligosaccharide intervention group (O), and glucose intervention group (G). All rats were sacrificed at the end of 9 weeks. Serum samples were collected for measuring gonadotropin releasing hormone, follicle stimulating hormone, luteinizing hormone, 1713-estradiol and progesterone levels. The ovaries were taken for investigation of exercise- and carbohydrate-induced follicular subcellular structure changes. Results: Exercise induced irregular menstrual cycles and ovary subcellular structural damages, such as swollenness of mitochondria in rats from groups E and R. Both glucose and oligosaccharide supplements restored well-differentiated mitochondria in the ovarian follicular cells, and a significant improvement of endoplasmic reticulum and Golgi in swollenness in theca cells in groups O and G compared to groups C, E, and R. There was no difference in mitochondria subcellular structural changes between groups O and G. Group E showed attenuation of serum levels of 17β-estradiol and progesterone compared to C. There were no differences of 17β-estradiol serum levels among groups O, G, and R, while group G showed a lower level of progesterone than C. Conclusion: Female adult rats with 9-week continuous exercise can cause menstrual dysregulation as a model for EAMD. Post-EAMD intervention with glucose and oligosaccharide intake can normalize the menstrual cycle, restore the follicular subcellular structure, and reverse the exercise-induced reduction of ovary sex hormones. It suggests a positive feedback of hypothalamus-pituitary-ovary axis might be involved in the molecular mechanisms of energy intake in treating EAMD. 展开更多
关键词 Carbohydrate supplement ESTRADIOL Estrous cycle restrain Follicular subcellular injury Ovary PROGESTERONE RATS
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Corn cob modified by lauric acid and ethanediol for emulsified oil adsorption
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作者 季振 林海 +2 位作者 陈月芳 董颖博 Muhammad Imran 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2096-2105,共10页
Corn cob is a naturally renewable material with developed micropore and hydrophobic characteristics, which enables it to show good oil adsorption capacity. In order to improve oil adsorption capacity, corn cob was mod... Corn cob is a naturally renewable material with developed micropore and hydrophobic characteristics, which enables it to show good oil adsorption capacity. In order to improve oil adsorption capacity, corn cob was modified with lauric acid and ethanediol. The structure of raw and modified corn cob was investigated using Fourier transform infrared(FTIR) spectroscopy, scanning electron microscopy(SEM), Brunauer-Emmett-Teller(BET) method, thermogravimetric analysis(TGA) and Ze Ta potential analyzer. The effects of p H level, adsorption time, adsorbent dosage, and initial oil concentration on oil absorbency of corn cob were studied. The results indicate that the modification significantly improved the lipophilicity of corn cob, making the modified corn cob with much better adsorption capacity on oil absorbency. Compared with raw corn cob, the maximum saturated adsorption capacity of modified corn cob is 16.52 mg/g at p H 5, and the increasing percentage is found to be 141%, which indicates that the modification causes a better adsorption capacity for oil removal. In addition, due to high oil adsorption capacity, affordable price and low secondary pollution, the modified corn cob could be considered promising alternative for the traditional oil adsorbent to clean up the emulsified oily water. 展开更多
关键词 emulsified oil corn cob lauric acid ethanediol LIPOPHILICITY
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Constructing Invariant Tori for the Spatial Hill Lunar Problem
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作者 Dongfeng YAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2016年第1期125-136,共12页
In this paper, the spatial Hill lunar problem is investigated, and the existence of invariant tori of hyperbolic type in a neighborhood of its equilibrium is shown. Moreover,the author checks the non-degenerate condit... In this paper, the spatial Hill lunar problem is investigated, and the existence of invariant tori of hyperbolic type in a neighborhood of its equilibrium is shown. Moreover,the author checks the non-degenerate condition analytically and obtains two-dimensional elliptic invariant tori on its central manifold as well. 展开更多
关键词 Spatial Hill lunar problem KAM theorem Quasi-periodic orbits Elliptic invariant tori
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