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基于卫星遥感海面温度数据的海洋锋分海区分析方法 被引量:5
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作者 陈标 马亮 +2 位作者 张春华 李冰 刘洪伟 《海洋工程》 CSCD 北大核心 2018年第2期108-118,共11页
为了能够合理准确地描述海洋锋特征体系以及锋区本身的各种结构要素,提出了一种中国近海海洋锋分海区分析方法:首先,在对中国近海27条典型海洋锋的时空分布特征和季节演变系统归纳的基础上,基于多年卫星遥感海面温度数据锋面出现频率图... 为了能够合理准确地描述海洋锋特征体系以及锋区本身的各种结构要素,提出了一种中国近海海洋锋分海区分析方法:首先,在对中国近海27条典型海洋锋的时空分布特征和季节演变系统归纳的基础上,基于多年卫星遥感海面温度数据锋面出现频率图,得出中国近海海区锋面系统划分方法;然后,利用日益更新的高时空分辨率卫星遥感海面温度数据,对各划分海区内海洋锋时空分布特征进行分析,调整纠正以往锋面系统分析的偏差或空缺,对中国近海锋面系统进行补充完善,为中国近海各锋面系统特征参数的规范化分析和准确的特征描述奠定基础。该方法对完善我国近海锋面系统研究具有长远的应用价值,对形成中远海及世界大洋海洋锋时空分布特征具有指导作用。 展开更多
关键词 海洋锋 分海区 卫星遥感 海面温度
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海岛地区分区大风预报探讨 被引量:9
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作者 王雷 王坚侃 《气象科技》 2005年第5期404-407,共4页
利用海岛自动测风站网的风力资料分析了舟山海域风力的分布特征,在此基础上有针对性地把舟山海域划分为5个海区,针对目前舟山沿海海面风力预报(公众预报)范围偏大,不能正确反映舟山海域风力局地特征的重大缺陷,提出了以分海区大风预报... 利用海岛自动测风站网的风力资料分析了舟山海域风力的分布特征,在此基础上有针对性地把舟山海域划分为5个海区,针对目前舟山沿海海面风力预报(公众预报)范围偏大,不能正确反映舟山海域风力局地特征的重大缺陷,提出了以分海区大风预报代替舟山沿海海面风力预报的设想和预报技术思路。预报实践表明:与目前的舟山沿海海面风力预报相比,分海区大风预报不仅更加客观合理和具有针对性,而且能够有效地解决海上安全与效益之间的矛盾,适合在海岛地区推广应用。 展开更多
关键词 舟山海域 自动测风站 风力特征 分海区大风预报 大风预报 海岛地区 舟山海域 舟山沿海 技术思路 海上安全 风力 海区
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Clarifying the relationship between PM2.5 and ozone complex pollution and synoptic patterns in a typical petrochemical city in the Bohai Rim region of China:Implications for air pollution forecasting and control 被引量:1
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作者 Yongxin Yan Cong An +7 位作者 Junling Li Yuanyuan Ji Rui Gao Hong Wang Fanyi Shang Linlin Ma Xiaoshuai Gao Hong Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期45-52,共8页
Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Don... Meteorological conditions are vital to PM_(2.5)and ozone(O_(3))complex pollution.Herein,the T-mode principal com-ponent analysis method was employed to objectively classify the 925-hPa geopotential height field of Dongying from 2017 to 2022.Synoptic patterns associated with four pollution types-namely,PM_(2.5)-only pollution,O_(3)-only pollution,Co-occurring of PM_(2.5)and O_(3)pollution,Non-occurring of PM_(2.5)and O_(3)pollution-were characterized at different time scales.The results indicated that synoptic classes conducive to PM_(2.5)-only pollution were“high-pressure top front”,“offshore high-pressure rear”,and“high-pressure inside”,while those conducive to O_(3)-only pollution were“offshore high-pressure rear”,“subtropical high”,and“high and low systems”.The Co-occurring of PM_(2.5)and O_(3)pollution were influenced by high pressure,and the Non-occurring of PM_(2.5)and O_(3)pollution were linked to precipitation and strong northerly winds.The variation in dominant synoptic patterns is crucial in the frequency changes of the four pollution types,which was further validated through the analysis of typical cases.Under the favorable meteorological conditions of high-pressure control with strong northerly winds or a subtropical high and inverted trough both with strong precipitation,there is potential to achieve coordinated control of PM_(2.5)and O_(3)in Dongying.Additionally,measures like artificially manipulating local humidity could be adopted to alleviate pollution levels.This study reveals the importance of comprehending the meteorological factors contributing to the formation of PM_(2.5)and O_(3)complex pollution for the improvement of urban air quality in the Bohai Rim region of China when emissions are high and the concentration of air pollutants exhibits high meteorological sensitivity. 展开更多
关键词 Synoptic classification T-mode principal component analysis Complex air pollution Correlation analysis Bohai Rim region
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Spatial Distribution of Soil Salinization Based on GIS in Tianjin Binhai New Area 被引量:3
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作者 廉晓娟 李明悦 +3 位作者 王艳 张余良 贺宏达 王正祥 《Agricultural Science & Technology》 CAS 2012年第5期1046-1049,共4页
The distribution of soil salinization was investigated based on GIS and field sampling in Tianjin Binhai New Area. The results showed that the average soil total salt content was 0.818%, with an average pH of 8.43, an... The distribution of soil salinization was investigated based on GIS and field sampling in Tianjin Binhai New Area. The results showed that the average soil total salt content was 0.818%, with an average pH of 8.43, and the average CI and Na+ contents were 0.27% and 0.22%, respectively. Presenting zonal distribution feature, the soil total salt content increased gradually from west to east of Binhai New Area. Statistics on the distribution areas of different salinization degrees showed that the area of non-salinzed soils only accounted for 3.18% of the total area; with an area of 107.43 km2, mild saline soil accounted for 6.34% of the total area; the area of moderate saline soil was 173.51 km2, accounting for 10.24%; and the area of sal- inzed soils was 217.36 km2, accounting for 12.82% of the total soil area. The area of saline soils (total salt content 〉0.6%) was 1 142.8 km2, accounting 67.42% of the total land area in Binhai New Area. And the areas for the soils with total salt content of 0.6%-1.0%, 1.0%-1.5%, 〉1.5% were respectively 388.47, 411.82, 342.51 km2, accounting for 22.92%, 24.3%, 20.21% of the total area. 展开更多
关键词 GIS Soil satinization Soil total salt content Binhai New Area Spatial distribution
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Analysis to the Driving Force Model and Driving Factor on the Utilized Changes of Cultivated Land in Gonghe County 被引量:14
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作者 俞文政 刘丹 +1 位作者 祁英香 史军 《Agricultural Science & Technology》 CAS 2009年第4期178-182,共5页
Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system d... Using gradually regression analysis to establish the driving force model of utilized change of cultivated land in Gonghe County, and using path analysis, correlation analysis, partial correlation analysis and system dynamics method to inspect the effect of driving changing on cultivated land change under different change situations. Driving factors, action mechanism and process of utilized change of cultivated land were analyzed from the county territory scale level. At last, some corresponding policies and measures were put forward. 展开更多
关键词 Gonghe County Utilized Change of cultivated land Driving force model Driving factors
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Vegetation Evolution in the Northern South China Sea Region Since 40 ka BP - An Attempt to Reconstruct Palaeovegetation Based on Biomization 被引量:3
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作者 罗运利 孙湘君 《Acta Botanica Sinica》 CSCD 2001年第11期1202-1206,共5页
Vegetation evolution in the northern South China Sea region since 40 500 a BP is reconstructed using biomization procedure based on pollen data from deep sea core 17940. The result shows that, it is feasible to recons... Vegetation evolution in the northern South China Sea region since 40 500 a BP is reconstructed using biomization procedure based on pollen data from deep sea core 17940. The result shows that, it is feasible to reconstruct palaeovegetation using biomization procedure, when pollen, particularly Pinus pollen, transported by mind over long distance is excluded. Results from factor analysis suggest that humidity and temperature are the two main factors determining vegetation evolution on land around the northern South China Sea. From 40 500 a BP to 11 100 a BP, broad-leaved evergreen forest (WAMF), and montane conifers(MGRF) occurred on hills and low mountains; while steppe (STEP) predominated on the exposed shelf. The main feature of the vegetation evolution is the frequent alternation between MGRF (or WAMF) and STEP, implying abrupt changes in millennium scale between humid/cold and dry/temperate climate. All abrupt climate events could be broadly correlated with Henrich events and Dansggard-Oscherge events. One of the events around 12 700 a BP, sees the occurrence of MGRF, suggesting that climate turned humid and cold rapidly. This may be correlated with the Younger Dryas event; Broad-leaved evergreen (WAMF) predominates since 11 000 a BP. During the early Holocene and late Holocene tropical rainforest (TRFO) or tropical seasonal forest (TSFO) occurred several times. 展开更多
关键词 POLLEN Biomization factor analysis South China Sea PALAEOVEGETATION
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Diversity and Florogenesis of Subnival Flora of the Caucasus 被引量:1
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作者 Shamil Shetekauri David Chelidze Nana Barnaveli 《Journal of Life Sciences》 2012年第8期917-930,共14页
This paper presents the results of systematic, ecopathological, and chorological studies of the diversity of the subnival belt (zone) flora of the Caucasus Mountains, peculiarity of altitudinal distribution, endemis... This paper presents the results of systematic, ecopathological, and chorological studies of the diversity of the subnival belt (zone) flora of the Caucasus Mountains, peculiarity of altitudinal distribution, endemism and florogenesis. Comparative analysis of the diversity of the subnival flora on different types of stone and at different altitudes in various parts of the Caucasus has been made. It is based on field investigation and on literature research. 226 species, 96 genera and 35 families were recorded in the subnival belt of the Caucasus within a range of 2,800 (2,900)-4,000 m a.s.l. Among these 117 species or 51% are common endemics of the Greater Caucasus and Caucasus. It is proved that floristic elements of different origin (authochronic and aloctonic) and age (Miocene-Pliocene and Pleistocene) contributed to the florogenesis of the subnival belt of the Caucasus. The Caucasian, the Eu-Caucasian, the Eastern Asian, the Minor Asian, the Dagestan-lranian, the Caucasia-European groups plaied an important role in the florogenesis. Criophilic evolution on the of the some plants was related to oreophytizacion during formation of the Caucasus mountains (in the second half of the Tertiary), as well as the glaciations scale. Species composition and coenotic role are different in various parts of the Caucasus and within each part. This is conditioned by the different hypsometry of various parts of the Caucasus, the character of glatiations, edaphic and climatic conditions, lythological diversity. Compared with the Greater Caucasus, the relative floristic poverty of the Lesser Caucasus is due to low elevations and extensive rather recent vulcanism. 展开更多
关键词 Caucasus mountain subnival flora geographycal isolation ENDEMIC glatiation volcanogenic rock-screes.
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APPROACH TO THE REGIONALIZATION OF A GRICULTURAL-PASTURALIZATION AROUND CHANGSHAN ISLANDS IN NORTHERN YELLOW SEA 被引量:1
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作者 ZHANG Yao-guang,DONG Li-jing,LI Chun-ping(Institute of Marine Resource,Liaon ing Normal University,Dalian 116029,P.R.China) 《Chinese Geographical Science》 SCIE CSCD 2002年第3期218-225,共8页
Based on the data of resources,environment and foundation of productio n,applying principal compo-nents-clustering quantitative analysis,this article divides the maritime space of Changshan Islands into three regions ... Based on the data of resources,environment and foundation of productio n,applying principal compo-nents-clustering quantitative analysis,this article divides the maritime space of Changshan Islands into three regions of agricultural-pasturalization,pr oviding a scientific basis for the ra tional distribution of marine culti vation.The three re-gions are as follows:1)The region of an agricultural-pastu ralization in the northern part of ma ritime space.It includes Da Wangjia and Shicheng islands.The ma in production is cultivation of praw n and molluscs in sea beach,float raft culture of mussel in shallow sea and scallop,and breeding of sea cucumber in subma rine.2)The region of agricultur-al-pasturalization in the middle we stern part of maritime space.It includes Da Changshan and Guanglu island s,and west-ern part of Xiao Chengshan Island.The main production is float raft cultu re of mussel and scallop in shallow se a,and breed-ing of sea cucumber in submarine.3)The region of agricultural-pastura lization of the southeastern part of maritime space.It includes the eastern part of Xiao ChangShan Island,Haiyang and Zhangzi islands.The main production is bre eding of abalone,sea cucumber,algaes and fish. 展开更多
关键词 Changshan Islands agricultural-pasturalization of seash ore principal compo-nents-clustering analysis region alization
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A new species of Eunice (Polychaeta: Eunicidae) from Hainan Island, South China Sea 被引量:1
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作者 吴旭文 孙瑞平 刘瑞玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期134-139,共6页
Ataxonomic survey of benthic marine animals from coastal regions of Hainan Island, South China Sea, revealed specimens of a new species of Eunice (Polychaeta: Eunicida: Eunicidae), Eunice uschakovi n. sp., collected f... Ataxonomic survey of benthic marine animals from coastal regions of Hainan Island, South China Sea, revealed specimens of a new species of Eunice (Polychaeta: Eunicida: Eunicidae), Eunice uschakovi n. sp., collected from the intertidal zone. The species belongs to the group of Eunice that has yellow tridentate subacicular hooks and branchiae scattered over an extensive region of the body. It resembles E. miurai and E. havaica in having both bidentate and tridentate falcigers, but can be readily distinguished by branchial features. Comparisons between E. uschakovi and the two related species are presented. 展开更多
关键词 ANNELIDA Eunicida TAXONOMY coastal regions intertidal zone
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Construction of Porphyra yezoensis Pure Line from Protoplasts and Its 18S rDNA Sequence Determination 被引量:3
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作者 LIUHongquan YUWengong +3 位作者 DAIJixun GONGQianhong SHIXiaochong YANGKunfeng 《Journal of Ocean University of China》 SCIE CAS 2004年第1期60-64,共5页
The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure lin... The wild Porphyra yezoensis collected from the Qingdao coast was used to prepare protoplasts by enzyme digestion. The pure line was constructed by cultivating the protoplasts. The 18S rDNA of the P. yezoensis pure line was cloned and sequenced. Sequence analysis was executed for this sequence and other 22 sequences retrieved from GenBank. A phylogenetic tree was constructed using the neighbor joining method. The results revealed a high diversity of 18S rDNA sequences in genus Porphyra and the considerable variation of 18S rDNA sequences in different strains of the same species P. yezoensis and P. tenera. Significant difference of 18S rDNA sequence was observed between P. yezoensis from Qingdao, China, and the two strains of P. yezoensis from Japan, but the three strains of P. yezoensis formed a stable clade in the phylogenetic tree. These results indicate the possibility of interspecies and intraspecies discrimination of Porphyra using the 18S rDNA sequences. 展开更多
关键词 Porphyra yezoensis 18S rDNA sequence analysis phylogenetic tree
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Integrating Remote Sensing and Field Survey to Map Shallow Water Benthic Habitat for the Kingdom of Bahrain
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作者 Sabah Aljenaid Eman Ghoneim +5 位作者 Mohammed Abido Khalil AlWedhai Ghadeer Khadim Saeed Mansoor Wisam EL-Deen Mohd Nadir Abd Hameed 《Journal of Environmental Science and Engineering(B)》 2017年第4期176-200,共25页
Identification and classification, as well as mapping of marine habitats, are of primary importance to plan management activities, especially in disturbed ecosystems like the ones in the marine areas of Bahrain. Remot... Identification and classification, as well as mapping of marine habitats, are of primary importance to plan management activities, especially in disturbed ecosystems like the ones in the marine areas of Bahrain. Remotely sensed Landsat-8 imagery coupled with field survey was used to identify, classify and map the benthic habitats in Bahrain marine area. The used geospatial techniques include advanced image processing procedures, which comprise of radiometric and atmospheric corrections, sun glint removal, water depth correction and image classification. Extensive ground-truthing analyses through in-situ field surveys by a team of scuba divers were conducted in October 2014 and June 2015 to inform and refine the classifications. The variables collected from this survey included physical and chemical characteristics of the water, habitat type, substrata, fauna and flora. A total of 176 field points were collected and utilized to perform an accurate assessment of the image classification. Initial habitat classification resulted in 20 habitat categories. However, due to the inability of the Landsat-8 sensors to accurately discriminate that level of classification, categories were merged into seven classes. The derived map shows that the benthic marine habitats of Bahrain consist of deep water (2,523 km2), rock (1,738 km2), sand (1,191 km2), deep water/sand (1,006 km2), algae (922 km2), seagrass (591 km2) and corals (275.50 km2). Although limited by the spatial and spectral resolutions of Landsat 8, the used methods produced a suitable map of the benthic habitats within the marine area of Bahrain with an overall accuracy of 84.1%. The use of very high spatial resolution satellite imagery will most likely increase such accuracy significantly. 展开更多
关键词 Landsat 8 MARINE water column correction scuba diving GIS (Geographic Information System)
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Analysis of geological conditions and thermal reservoir characteristics of Guantao Formation in new coastal region 被引量:1
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作者 JIANG Guosheng HUANG Xianlong +3 位作者 HU Liangjun ZHANG Liandi LIU Zan LU Bao 《Global Geology》 2013年第4期201-206,共6页
Geothermal resources is one of the most practical and competitive new energy at present,and there is abundant geothermal resources in the new coastal region.The article get the three following conclusion through the g... Geothermal resources is one of the most practical and competitive new energy at present,and there is abundant geothermal resources in the new coastal region.The article get the three following conclusion through the geothermal geological condition by the drilling strata and the condition of the reducing test:stratigraphic division is done by the analysis of formation lithology and the drilling aging;the water yield is higher than 100m3/h,the flow temperature is 67℃--71℃;the average geothermal gradient of the overlying strata is 3.08℃--3.33℃/100 m. 展开更多
关键词 the new coastal region geothermal well Guantao Formation drilling time aging
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A Preliminary Study on the New Activity Features of the Lajishan Mountain Fault Zone in Qinghai Province 被引量:3
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作者 Yuan Daoyang Zhang Peizhen +2 位作者 Lei Zhongsheng Liu Baichi Liu Xiaolong 《Earthquake Research in China》 2005年第4期391-401,共11页
The Lajishan Mountain fault zone consists of two NE_protruding arcuate faults, i.e. the northern and southern margin fault of Lajishan Mountain with the fault length of 230km and 220km respectively. The fault zone is ... The Lajishan Mountain fault zone consists of two NE_protruding arcuate faults, i.e. the northern and southern margin fault of Lajishan Mountain with the fault length of 230km and 220km respectively. The fault zone is located in the large_scale compressional structure zone and tectonic gradient zone in_between the NNW_trending right_lateral strike_slip Reshui_Riyueshan fault zone and the NWW_trending left_lateral strike_slip northern margin of west Qinling Ranges fault zone is also an important boundary fault zone, separating the Xining_Minhe basin and the Xunhua_Hualong basin at the southern and northern sides of the Lajishan Mountain respectively. Geologic geomorphic evidences of new activity revealed by field investigations indicate that the latest movement of the Lajishan fault zone was in late Epipleistocene (only a few segments were active in early Holocene) and is mainly of compressive thrusting with slightly left_lateral strike_slip component. The above movement has possibly resulted in the occurrence of about 20 moderate earthquakes of magnitude around 5.0. The Lajishan region can therefore be regarded as a seismotectonic window to reflect tectonic movement and earthquake activity. 展开更多
关键词 Lajishan Mountain Active fault Historical earthquake New activity
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A Storm Surge Intensity Classification Based on Extreme Water Level and Concomitant Wave Height 被引量:4
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作者 DONG Sheng GAO Junguo +2 位作者 LI Xue WEI Yong WANG Liang 《Journal of Ocean University of China》 SCIE CAS 2015年第2期237-244,共8页
Storm surge is one of the predominant natural threats to coastal communities. Qingdao is located on the southern coast of the Shandong Peninsula in China. The storm surge disaster in Qingdao depends on various influen... Storm surge is one of the predominant natural threats to coastal communities. Qingdao is located on the southern coast of the Shandong Peninsula in China. The storm surge disaster in Qingdao depends on various influencing factors such as the intensity, duration, and route of the passing typhoon, and thus a comprehensive understanding of natural coastal hazards is essential. In order to make up the defects of merely using the warning water level, this paper presents two statistical distribution models(Poisson Bi- variable Gumbel Logistic Distribution and Poisson Bi-variable Log-normal Distribution) to classify the intensity of storm surge. We emphasize the joint return period of typhoon-induced water levels and wave heights measured in the coastal area of Qingdao since 1949. The present study establishes a new criterion to classify the intensity grade of catastrophic storms using the typhoon surge estimated by the two models. A case study demonstrates that the new criterion is well defined in terms of probability concept, is easy to implement, and fits well the calculation of storm surge intensity. The procedures with the proposed statistical models would be useful for the disaster mitigation in other coastal areas influenced by typhoons. 展开更多
关键词 storm surge Poisson Bi-variable Gumbel Logistic distribution Poisson Bi-variable Log-normal distribution intensityclassification joint return period
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Tidal analysis in the venturi-shaped area between Zhenhai and Shenjiamen in the East China Sea 被引量:2
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作者 吕华庆 胡建炯 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期103-111,共9页
In order to better understand the general tidal features in the venturi-shaped area between Zhenhai and Shenjiamen in the northern coastal region of Zhejiang Province in the East China Sea, the tidal data were obtaine... In order to better understand the general tidal features in the venturi-shaped area between Zhenhai and Shenjiamen in the northern coastal region of Zhejiang Province in the East China Sea, the tidal data were obtained from both the three permanent tide stations of Zhenhai, Dinghai and Shenjiamen, and four temporary tide stations of Mamu, Chuanshan, Guoju and Liuheng, along with the current speed being observed at Luotou Waterway. Results from harmonic analysis show that: (1) The area was dominated by shallow water tides with irregular semi-diurnal features, and the smallest tidal range occurred in the area near a crossing line between Zhenhai and Dinghai stations, indicating that a tidal node existed in the southern Hangzhou Bay; (2) Formulae, HS2/HM2 >0.4 and gM2-(gK1+gO1)=270° (where H and g are harmonic constants), could be used as judging criteria for high and low tidal level diurnal inequalities; (3) The duration difference between ebb and flood tides could be roughly assessed by the ratio of HM4 vs. HM2; and the larger the ratio is, the bigger the duration difference is. At the same time, the duration period could be assessed by 2gM2-gM4, the epoch difference between M2 and M4 tidal constituents. If 2gM2-gM4 <180°, then the ebb duration is longer than the flood duration; if 180°< 2gM2-gM4 <360°, the result is reversed; (4) Taking Dinghai station as a center point, the highest tidal levels and the average high tidal levels, as well as the average tidal ranges at all stations became higher and larger both southeastwards and northwestwards, while the lowest tidal levels and the average low tidal levels appeared to be lower both southeastwards and northwestwards; and (5) The tidal patterns were not all in line with the tidal current patterns. As a conclusion, the smallest tidal range occurred in the narrow part of the venturi-shaped area. Along the both sides of the area, the highest tidal level and tidal range became higher and larger, while the lowest tidal level became lower with the increase of the distance from the narrow throat area. This is somehow different from the theory that the tidal level increases gradually when it moves towards the top narrow area of a V-shaped bay or estuary. 展开更多
关键词 East China Sea harmonic analysis Luotou Waterway tidal features venturi-shaped area Zhejiang coastal water
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A STUDY OF PARTITIONING Q VECTOR ON BACKGROUND CONDITIONS OF A TORRENTIAL RAINFALL OVER SHANGHAI,CHINA ON 25 AUGUST 2008 被引量:4
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作者 岳彩军 鲁小琴 +1 位作者 李小凡 宗志平 《Journal of Tropical Meteorology》 SCIE 2011年第3期231-247,共17页
A rainfall that occurred during 0200–1400 Beijing Standard Time(BST)25 August 2008 shows the rapid development of a convective system,a short life span,and a record rate of 117.5 mm h-1for Xujiahui station since 1872... A rainfall that occurred during 0200–1400 Beijing Standard Time(BST)25 August 2008 shows the rapid development of a convective system,a short life span,and a record rate of 117.5 mm h-1for Xujiahui station since 1872.To study this torrential rainfall process,the partitioning method of Q vector is developed,in which a moist Q vector is first separated into a dry ageostrophic Q vector(DQ)and a diabatic-heating component.The dry ageostrophic Q vector is further partitioned along isothermal lines in the natural coordinate to identify different scale forcing in adiabatic atmosphere,and the large-scale and convective condensational heating in non-uniform saturated atmosphere,convective condensational heating, and Laplace of diabatic heating that includes radiative heating and other heating and cooling processes,are calculated to study the forcing from diabatic heating.The effects of the environmental conditions on the development of the rainfall processes are diagnosed by performing the partitioning of Q vector based on 6-hourly NCEP/NCAR Final Analysis(FNL)data with the horizontal resolution of 1°×1°.The results include the following:(1)a low-pressure inverted trough associated with the landfall of Typhoon Nuri (2008),a strong southwesterly jet along the western side of the subtropical high,and an eastward-propagating westerly low-pressure trough provide favorable synoptic conditions for the development of torrential rainfall;(2)the analysis of DQ vector showed that the upward motions forced by the convergence of DQ vector in the lower troposphere(1000–600 hPa)favor the development of torrential rainfall.When DQ vector converges in the upper troposphere(500–100 hPa),upward motions in the whole air column intensify significantly to accelerate the development of torrential rainfall;(3)the partitioning analysis of DQ vector reveals that large-scale forcing persistently favors the development of torrential rainfall whereas the mesoscale forcing speeds up the torrential rainfall;(4)the calculations of large-scale condensational heating in non-uniform saturated atmosphere,convective condensational heating, and Laplace of diabatic heating showed that the forcing related to diabatic heating has the positive feedback on the convective development,and such positive feedback decays and dissipates when the convective system propagates eastward and weakens. 展开更多
关键词 background conditions of torrential rainfall partitioning of Q vector dry ageostrophic Q vector diabatic heating
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Chlorophyll a and Trophic State in the Boka Kotorska Bay (Eastern Adriatic Sea)
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作者 S. Krivokapic B. Pestoric 《Journal of Environmental Science and Engineering》 2011年第4期420-427,共8页
The monthly changes in chlorophyll a, phytoplankton abundance and physicochemical parameters at two stations in Boka Kotorska Bay were investigated between 2003-2004. Nutrient salts varied widely, with maximum 3.65 μ... The monthly changes in chlorophyll a, phytoplankton abundance and physicochemical parameters at two stations in Boka Kotorska Bay were investigated between 2003-2004. Nutrient salts varied widely, with maximum 3.65 μmol.L^-1 for nitrates and 0.23 μmol.L^-1 for phosphate. Chlorophyll a concentration ranged from 0.25 to 7.63 mg·m^3 and the highest value was measured in winter period of year. It seems that reason for this is the land-based nutrient input into the coastal area here. According to chlorophyll a, nitrates and phosphates concentrations, the area could be oligomesotrophic to mesotrophic during winter. 展开更多
关键词 Chlorophyll a EUTROPHICATION Adriatic Sea.
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Decentralized PID neural network control for a quadrotor helicopter subjected to wind disturbance 被引量:10
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作者 陈彦民 何勇灵 周岷峰 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第1期168-179,共12页
A decentralized PID neural network(PIDNN) control scheme was proposed to a quadrotor helicopter subjected to wind disturbance. First, the dynamic model that considered the effect of wind disturbance was established vi... A decentralized PID neural network(PIDNN) control scheme was proposed to a quadrotor helicopter subjected to wind disturbance. First, the dynamic model that considered the effect of wind disturbance was established via Newton-Euler formalism.For quadrotor helicopter flying at low altitude in actual situation, it was more susceptible to be influenced by the turbulent wind field.Therefore, the turbulent wind field was generated according to Dryden model and taken into consideration as the disturbance source of quadrotor helicopter. Then, a nested loop control approach was proposed for the stabilization and navigation problems of the quadrotor subjected to wind disturbance. A decentralized PIDNN controller was designed for the inner loop to stabilize the attitude angle. A conventional PID controller was used for the outer loop in order to generate the reference path to inner loop. Moreover, the connective weights of the PIDNN were trained on-line by error back-propagation method. Furthermore, the initial connective weights were identified according to the principle of PID control theory and the appropriate learning rate was selected by discrete Lyapunov theory in order to ensure the stability. Finally, the simulation results demonstrate that the controller can effectively resist external wind disturbances, and presents good stability, maneuverability and robustness. 展开更多
关键词 quadrotor helicopter PID neural network(PIDNN) turbulent wind field discrete Lyapunov theory
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The Biodiversity of Cyprus Island
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作者 Alessandro Lentini 《Journal of Environmental Science and Engineering(B)》 2015年第3期125-131,共7页
The aspects considered in this paper refer to remains of food plants found in the archaeological area of Pyrgos (Early Bronze Age, 2000 B.C.) near Limassol in Cyprus, related to the history of agriculture and cultiv... The aspects considered in this paper refer to remains of food plants found in the archaeological area of Pyrgos (Early Bronze Age, 2000 B.C.) near Limassol in Cyprus, related to the history of agriculture and cultivated plant processing technologies. For the purposes of an initial comparison of the archaeobotanical data, the authors updated a map of rainfall distribution on Cyprus with rainfall and temperature data for the period from 1973 to 2007, to produce an updated view of possible microclimates on the island. Cyprus was one of the Mediterranean islands whose particular orographic features encouraged the phylogenetic evolution of many species, and today it is especially rich in endemic species. Cyprus located at the southeastern boundary among the Mediterranean region, the Pontic region (the Irano-Turanic element) and the Near East (the Syriac and Nubo-Sindic elements) it doesn't seem to have effectively influenced the most important endemic species, they were probably preserved by the island's microclimates and particular edaphic conditions. 展开更多
关键词 BIODIVERSITY Cyprus geobotany ARCHAEOLOGY seeds macroremains Mediterranean basin.
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The Impact of Colonial Rule on the Gyaman State
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作者 Agyemang, Joseph Kwadwo Ofosu-Mensah Ababio Emmanuel Gyamerah Ebenezer Yaw 《History Research》 2013年第6期389-405,共17页
The balkanisation of the African continent by the European powers in the nineteenth century caused the territorial division of people with the same ancestry into two or more states under different European governments... The balkanisation of the African continent by the European powers in the nineteenth century caused the territorial division of people with the same ancestry into two or more states under different European governments. During the partition, the European powers did not take into consideration the cultural and historical boundaries of the people of Africa. In West Africa for example, the partition made some Nzema people to be found in La Cote d'Ivoire and in Ghana. Some Dagarti are also found in Burkina Faso and while others remained in Ghana. Ewes today can be found in the three countries of Ghana, Togo and Benin. The same applies to the Bono in Gyaman. Some of the Gyaman people can be found in the Ivory Coast with others in Ghana. This article discusses Gyaman under the British and French colonial rule. It focuses on the responses of Gyaman authorities to colonialism and details out British and French colonial policies and their impact on the Gyaman people. 展开更多
关键词 Gyaman BRITISH FRENCH COLONIAL Ghana Cote d'Ivoire.
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