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Transformation from Town Gas to Renewable Energy Business
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作者 Don Cheng Hill-kwong Charles Tsoi Chau-chi 《China Oil & Gas》 2025年第1期82-86,共5页
As an established environmental scholar once mentioned,“we do not inherit resources from the earth,we borrow them from the future”.Since 2011,the concentration of greenhouse gases in the atmosphere has continued to ... As an established environmental scholar once mentioned,“we do not inherit resources from the earth,we borrow them from the future”.Since 2011,the concentration of greenhouse gases in the atmosphere has continued to rise.In 2019,the annual average concentration of carbon dioxide reached 410 ppm,methane reached 1,866 ppb,and nitrous oxide reached 332 ppb. 展开更多
关键词 TRANSFORMATION mentioned dioxide
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Modeling of Precipitation over Africa:Progress,Challenges,and Prospects
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作者 A.A.AKINSANOLA C.N.WENHAJI +21 位作者 R.BARIMALALA P.-A.MONERIE R.D.DIXON A.T.TAMOFFO M.O.ADENIYI V.ONGOMA I.DIALLO M.GUDOSHAVA C.M.WAINWRIGHT R.JAMES K.C.SILVERIO A.FAYE S.S.NANGOMBE M.W.POKAM D.A.VONDOU N.C.G.HART I.PINTO M.KILAVI S.HAGOS E.N.RAJAGOPAL R.K.KOLLI S.JOSEPH 《Advances in Atmospheric Sciences》 2026年第1期59-86,共28页
In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and cha... In recent years,there has been an increasing need for climate information across diverse sectors of society.This demand has arisen from the necessity to adapt to and mitigate the impacts of climate variability and change.Likewise,this period has seen a significant increase in our understanding of the physical processes and mechanisms that drive precipitation and its variability across different regions of Africa.By leveraging a large volume of climate model outputs,numerous studies have investigated the model representation of African precipitation as well as underlying physical processes.These studies have assessed whether the physical processes are well depicted and whether the models are fit for informing mitigation and adaptation strategies.This paper provides a review of the progress in precipitation simulation overAfrica in state-of-the-science climate models and discusses the major issues and challenges that remain. 展开更多
关键词 RAINFALL MONSOON climate modeling CORDEX CMIP6 convection-permitting models
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Recent Progress in JAXA Project of Boiling Two-Phase Flow Experiment onboard ISS
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作者 Kiyosumi Fujii Masato Komasaki +8 位作者 Takashi Kurimoto Haruo Kawasaki Kenichiro Sawada Koichi Suzuki Hitoshi Asano Osamu Kawanami Ryoji Imai Yasuhisa Shinmoto Haruhiko Ohta 《Journal of Physical Science and Application》 2012年第4期71-79,共9页
The amount of waste heat in a space facility became larger, because of increase in the space platform size and its power consumption. It requires development of high-performance space thermal management systems handli... The amount of waste heat in a space facility became larger, because of increase in the space platform size and its power consumption. It requires development of high-performance space thermal management systems handling a large amount of waste. Boiling two-phase flow could become powerful means for this system because a boiling and condensation system is one of the most efficient modes of heat transfer due to phase change (liquid-vapor). However, gravity effects on boiling two-phase flow phenomena and the corresponding heat transfer characteristics are not clear. Therefore, we prepare the experiments of boiling two-phase flow utilizing a long-term microgravity environment onboard a Japanese Experimental Module "KIBO" in the International Space Station (ISS) as one of the JAXA official projects. In this paper, recent progress of the preparation for the project is reported. 展开更多
关键词 Boiling two-phase flow space science space technology ISS experiment microgravity.
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Foundation Treatments for Embankments over Highly Compressible Peat in CKE Project
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作者 Qi Zhang Xiaqiang Qin +1 位作者 Heping Dong Xia Yan 《Journal of Civil Engineering and Architecture》 2011年第12期1138-1141,共4页
The construction of CKE road embankments is undertaken over soft soils,which include peats,organic soils,clays and sludge.The moisture content of peat is up to 700%and void ratio is up to 11.99.It's very easy for ... The construction of CKE road embankments is undertaken over soft soils,which include peats,organic soils,clays and sludge.The moisture content of peat is up to 700%and void ratio is up to 11.99.It's very easy for the embankments of high moisture content,high void ratio and of the high compression nature to cause too much settlement and loss of stability.Embankment stability during construction and residual settlement of pavement during service period are two major challenges to be faced of the design and construction.This paper outlines the site investigation,laboratory tests and monitoring data in a few selected existing preloading areas,and presents the back-analysis results of the modified secondary compression indices of in-situ soft materials.It is found that the early monitoring data after primary settlement completion are a more reliable approach to estimate the residual settlements within a nominated duration. 展开更多
关键词 Highly compressible peat study of residual settlement.
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Naypyitaw Office Held Multilingual Speech Contest for Local Staff
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作者 Ge Qianbing Xia Donglun 《China Oil & Gas》 CAS 2022年第2期54-55,共2页
In order to enrich the life of the local staff,make their voices heard,and promote the cultural integration between China and Myanmar,as the Myanmar Songkran was approaching,the SinoMyanmar Pipeline project Naypyidaw ... In order to enrich the life of the local staff,make their voices heard,and promote the cultural integration between China and Myanmar,as the Myanmar Songkran was approaching,the SinoMyanmar Pipeline project Naypyidaw office(hereinafter referred to as“Naypyitaw office”)held the annual multilingual speech contest for Myanmar staff on 9 April to welcome the Myanmar New Year,and 27 in-service Myanmar employees all participated enthusiastically in the contest. 展开更多
关键词 service OFFICE APPROACHING
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Current Situation and Prospect of Water Conservancy Project Operation and Management
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作者 SHI Jiangfeng 《外文科技期刊数据库(文摘版)工程技术》 2021年第3期554-558,共5页
Based on a series of investigation and Research on the current situation of water conservancy project operation and management, this paper will point out some problems existing in the current management work for the r... Based on a series of investigation and Research on the current situation of water conservancy project operation and management, this paper will point out some problems existing in the current management work for the relevant industry. This paper expounds the actual situation of water conservancy project operation and management in the current society, and analyzes some problems that should be paid attention to in the operation and management of water conservancy projects. 展开更多
关键词 water conservancy project operation management security management
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Multi-granularity feature enhancement network for maritime ship detection
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作者 Li Ying Duoqian Miao +2 位作者 Zhifei Zhang Hongyun Zhang Witold Pedrycz 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第3期649-664,共16页
Due to the characteristics of high resolution and rich texture information,visible light images are widely used for maritime ship detection.However,these images are suscep-tible to sea fog and ships of different sizes... Due to the characteristics of high resolution and rich texture information,visible light images are widely used for maritime ship detection.However,these images are suscep-tible to sea fog and ships of different sizes,which can result in missed detections and false alarms,ultimately resulting in lower detection accuracy.To address these issues,a novel multi-granularity feature enhancement network,MFENet,which includes a three-way dehazing module(3WDM)and a multi-granularity feature enhancement module(MFEM)is proposed.The 3WDM eliminates sea fog interference by using an image clarity automatic classification algorithm based on three-way decisions and FFA-Net to obtain clear image samples.Additionally,the MFEM improves the accuracy of detecting ships of different sizes by utilising an improved super-resolution reconstruction con-volutional neural network to enhance the resolution and semantic representation capa-bility of the feature maps from YOLOv7.Experimental results demonstrate that MFENet surpasses the other 15 competing models in terms of the mean Average Pre-cision metric on two benchmark datasets,achieving 96.28%on the McShips dataset and 97.71%on the SeaShips dataset. 展开更多
关键词 object classification object recognition rough sets rough set theory
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Recent advances in geology and exploration in the Balkash-western Junggar region(Kazakhstan and Xinjiang,China):Report on the“International workshop on the large Balkash-western Junggar copper-gold province” 被引量:1
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作者 Yongfeng Zhu Qinming Yan +1 位作者 Huadong Ma Bernd Lehmann 《Episodes》 2011年第3期208-211,共4页
An“International workshop on the large Balkash-western Junggar copper-gold province”,supported by National 305 Project Office,International S&T Cooperation Program of China,the National Natural Science Foundatio... An“International workshop on the large Balkash-western Junggar copper-gold province”,supported by National 305 Project Office,International S&T Cooperation Program of China,the National Natural Science Foundation of China,and PetrolChina Xinjiang Branch,was held in Karamay,Xinjiang Uygur Autonomous Region,from 22 to 27 August,2011(Fig.1). 展开更多
关键词 national project EXPLORATION large balkash western junggar copper gold province national project officeinternational international s t cooperation program natural science foundation national natural science foundation international workshop
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Turbulent Variance Characteristics of Temperature and Humidity over a Non-uniform Land Surface for an Agricultural Ecosystem in China 被引量:9
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作者 高志球 卞林根 +2 位作者 谌志刚 Michael SPARROW 张佳华 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2006年第3期365-374,共10页
This paper describes the application of the variance method for flux estimation over a mixed agricultural region in China. Eddy covariance and flux variance measurements were conducted in a near-surface layer over a n... This paper describes the application of the variance method for flux estimation over a mixed agricultural region in China. Eddy covariance and flux variance measurements were conducted in a near-surface layer over a non-uniform land surface in the central plain of China from 7 June to 20 July 2002. During this period, the mean canopy height was about 0.50 m. The study site consisted of grass (10% of area), beans (15%), corn (15%) and rice (60%). Under unstable conditions, the standard deviations of temperature and water vapor density (normalized by appropriate scaling parameters), observed by a single instrument, followed the Monin-Obukhov similarity theory. The similarity constants for heat (CT) and water vapor (Cq) were 1.09 and 1.49, respectively. In comparison with direct measurements using eddy covariance techniques, the flux variance method, on average, underestimated sensible heat flux by 21% and latent heat flux by 24%, which may be attributed to the fact that the observed slight deviations (20% or 30% at most) of the similarity "constants" may be within the expected range of variation of a single instrument from the generally-valid relations. 展开更多
关键词 turbulent fluxes eddy covariance flux variance non-uniform land surface
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Active and passive smoking with breast cancer risk for Chinese females: a systematic review and meta-analysis 被引量:13
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作者 Chuan Chen Yu-Bei Huang +9 位作者 Xue-Ou Liu Ying Gao Hong-Ji Dai Feng-Ju Song Wei-Qin Li Jing Wang Ye Yan Pei-Shan Wang Yao-Gang Wang Ke-Xin Chen 《Chinese Journal of Cancer》 SCIE CAS CSCD 2014年第6期306-316,共11页
Previous studies suggested that smoking and passive smoking could increase the risk of breast cancer, but the results were inconsistent, especially for Chinese females. Thus, we systematically searched cohort and case... Previous studies suggested that smoking and passive smoking could increase the risk of breast cancer, but the results were inconsistent, especially for Chinese females. Thus, we systematically searched cohort and case-control studies investigating the associations of active and passive smoking with breast cancer risk among Chinese females in four English databases(PubMed, Embase, ScienceDirect, and Wiley) and three Chinese databases(CNKI, WanFang, and VIP). Fifty-one articles(3 cohort studies and 48 casecontrol studies) covering 17 provinces of China were finally included in this systematic review. Among Chinese females, there was significant association between passive smoking and this risk of breast cancer [odds ratio(OR): 1.62; 95% confidence interval(CI): 1.39–1.85; I2 = 75.8%, P < 0.001; n = 26] but no significant association between active smoking and the risk of breast cancer(OR: 1.04; 95% CI: 0.89–1.20; I2 = 13.9%, P = 0.248; n = 31). The OR of exposure to husband's smoking and to smoke in the workplace was 1.27(95% CI: 1.07–1.50) and 1.66(95% CI: 1.07–2.59), respectively. The OR of light and heavy passive smoking was 1.11 and 1.41, respectively, for women exposed to their husband's smoke(< 20 and ≥ 20 cigarettes per day), and 1.07 and 1.87, respectively, for those exposed to smoke in the workplace(< 300 and ≥ 300 min of exposure per day). These results imply that passive smoking is associated with an increased risk of breast cancer, and the risk seems to increase as the level of passive exposure to smoke increases among Chinese females. Women with passive exposure to smoke in the workplace have a higher risk of breast cancer than those exposed to their husband's smoking. 展开更多
关键词 被动吸烟 乳腺癌 风险 中国 女性 系统 工作场所 队列研究
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A bird's eye view of the air pollution-cancer link in China 被引量:7
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作者 Yu-Bei Huang Feng-Ju Song +3 位作者 Qun Liu Wei-Qin Li Wei Zhang Ke-Xin Chen 《Chinese Journal of Cancer》 SCIE CAS CSCD 2014年第4期176-188,共13页
Air pollution in China comes from multiple sources,including coal consumption,construction and industrial dust,and vehicle exhaust.Coal consumption in particular directly determines the emissions of three major air po... Air pollution in China comes from multiple sources,including coal consumption,construction and industrial dust,and vehicle exhaust.Coal consumption in particular directly determines the emissions of three major air pollutants:dust,sulfur dioxide(SO2),and nitrogen oxide(NOx).The rapidly increasing number of civilian vehicles is expected to bring NOx emission to a very high level.Contrary to expectations,however,existing data show that the concentrations of major pollutants[particulate matter-10(PM10),SO2,and nitrogen dioxide(NO2)]in several large Chinese cities have declined during the past decades,though they still exceed the national standards of ambient air quality.Archived data from China does not fully support that the concentrations of pollutants directly depend on local emissions,but this is likely due to inaccurate measurement of pollutants.Analyses on the cancer registry data show that cancer burden related to air pollution is on the rise in China and will likely increase further,but there is a lack of data to accurately predict the cancer burden.Past experience from other countries has sounded alarm of the link between air pollution and cancer.The quantitative association requires dedicated research as well as establishment of needed monitoring infrastructures and cancer registries.The air pollution-cancer link is a serious public health issue that needs urgent investigation. 展开更多
关键词 空气污染物 中国城市 癌症 链接 鸟瞰图 NOX排放 环境空气质量 公共卫生问题
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Application of multi-attribute matching technology based on geological models for sedimentary facies:A case study of the 3rd member in the Lower Jurassic Badaowan Formation,Hongshanzui area,Junggar Basin,China 被引量:4
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作者 Zong-Quan Yao Fan Yang +6 位作者 Deleqiati Jianatayi Wei Wang Yang Gao Le Sun Wen-Feng Wang Bo-Yu Mu Pin-Bai Pan 《Petroleum Science》 SCIE CAS CSCD 2022年第1期116-127,共12页
Regarding high drilling costs,an effort should be made to substantially reduce the drilling operation.To achieve this goal,exploration and development stages should be carried out precisely with maximum information ac... Regarding high drilling costs,an effort should be made to substantially reduce the drilling operation.To achieve this goal,exploration and development stages should be carried out precisely with maximum information acquired from the reservoir.The use of multi-attribute matching technology to predict sedimentary system has always been a very important but challenging task.To resolve the challenges,we utilized a quantitative analysis method of seismic attributes based on geological models involving high resolution 3D seismic data for sedimentary facies.We developed a workflow that includes core data,seismic attribute analysis,and well logging to highlight the benefit of understanding the facies distribution in the 3 rd Member of the Lower Jurassic Badaowan Formation,Hongshanzui area,Junggar Basin,China.1)Data preprocessing.2)Cluster analysis.3)RMS attribute based on a normal distribution constrains facies boundary.4)Mapping the sedimentary facies by using MRA(multiple regression analysis)prediction model combined with the lithofacies assemblages and logging facies assemblages.The confident level presented in this research is 0.745,which suggests that the methods and data-mining techniques are practical and efficient,and also be used to map facies in other similar geological settings. 展开更多
关键词 Clustering analysis Mapping the sedimentary facies Normal distribution Multi-attribute matching Hongshanzui area
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Physical Properties of Liquid Terbium Measured by Levitation Techniques 被引量:2
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作者 Paul-Francois Paradis Takehiko Ishikawa +1 位作者 Noriyuki Koike Yuki Watanabe 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第6期665-669,共5页
To understand the nature and behavior of rare earth metals in their liquid phases, accurate values of their physical properties are essential. However, to measure their physical properties, the samples should be maint... To understand the nature and behavior of rare earth metals in their liquid phases, accurate values of their physical properties are essential. However, to measure their physical properties, the samples should be maintained in liquid phases for prolonged time, and this raises a formidable challenge. This is mainly explained by their high melting temperatures (e.g., 1629 K for Tb), high vapor pressure, and the risk of melt contamination with a crucible or support. An electrostatic levitation furnace alleviated these difficulties and allowed the determination of density, surface tension, and viscosity of several metals above their melting temperature. Here, first, the levitation furnace facility and the noncontact diagnostic procedures were briefly discussed, followed by the explanation of their thermophysical property measurements over wide temperature ranges. The density was obtained using an ultraviolet-based imaging technique that allowed excellent illumination, even at elevated temperatures. Over the 1615 to 1880 K temperature span, the density measurements could be expressed as p(T) =7.84 × 10^3 -0.47 (T - Tm) (kg · m^-3) with Tm = 1629 K, yielding a volume expansion coefficient a(T) = 6.0 × 10^-5 (K^-1). In addition, the surface tension and the viscosity could be determined by inducing a drop oscillation to a molten sample. Using this technique, the surface tension data could be expressed as σ(T) = 8.93 × 10^2 - 0.10 (T - Tm)(mN· m^-1) and those for viscosity as η(T) =0.583 exp [4.1 × 10^4/(RT)] (MPa·s) over the 1690 to 1980 K temperature range 展开更多
关键词 LEVITATION LIQUID NONCONTACT TERBIUM rare earths
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Validating the Runoff from the PRECIS Model Using a Large-Scale Routing Model 被引量:3
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作者 曹丽娟 董文杰 +2 位作者 许吟隆 张勇 Michael SPARROW 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第5期855-862,共8页
The streamflow over the Yellow River basin is simulated using the PRECIS (Providing REgional Climates for Impacts Studies) regional climate model driven by 15-year (1979-1993) ECMWF reanalysis data as the initial ... The streamflow over the Yellow River basin is simulated using the PRECIS (Providing REgional Climates for Impacts Studies) regional climate model driven by 15-year (1979-1993) ECMWF reanalysis data as the initial and lateral boundary conditions and an off-line large-scale routing model (LRM). The LRM uses physical catchment and river channel information and allows streamflow to be predicted for large continental rivers with a 1°×1° spatial resolution. The results show that the PRECIS model can reproduce the general southeast to northwest gradient distribution of the precipitation over the Yellow River basin, The PRECIS- LRM model combination has the capability to simulate the seasonal and annual streamflow over the Yellow River basin. The simulated streamflow is generally coincident with the naturalized streamflow both in timing and in magnitude. 展开更多
关键词 regional climate model large-scale routing model model validation RUNOFF the Yellow River
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Geochronology and Geochemistry of the Early Paleozoic Ore-host Volcanic Sequence in the Kalatag Area,East Tianshan,NW China:Implications for the Tectonic Evolution 被引量:2
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作者 ZHANG Zhenlong YANG Fuquan +4 位作者 ZHOU Taofa GENG Xinxia ZHANG Zhixin YANG Chengdong QIU Zhanlin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第5期1372-1387,共16页
The East Tianshan contains many late Paleozoic magmatic and polymetallic deposits.Recent studies demonstrate that the early Paleozoic volcanic rocks discovered in the northern region of East Tianshan can be subdivided... The East Tianshan contains many late Paleozoic magmatic and polymetallic deposits.Recent studies demonstrate that the early Paleozoic volcanic rocks discovered in the northern region of East Tianshan can be subdivided into the Daliugou,Hongliuxia and Kalatag formations.Here,we report zircon U-Pb ages of volcanic rocks and quartz diorite porphyry,together with whole-rock geochemical and Sr-Nd isotope data of early Paleozoic volcanic rocks,in order to investigate their petrogenesis and geodynamic setting.Zircon U-Pb analyses of the rocks suggest that the Kalatag Formation formed at ca.438-413 Ma.Geochemical characteristics of the early Paleozoic volcanic rocks exhibit typical subduction-related features.They have high Mg^(#)(44-75),positiveε_(Nd)(t)values(0.25-7.88),low^(87)Sr/^(86)Sr ratios(0.70457 to 0.70588)and young two-stage Hf isotope model ages(551-446 Ma),consistent with a depleted mantle origin with limited crustal contamination.The basaltic andesite and andesite have relatively high MgO contents(6.1-9.4 wt%),suggesting that they belong to high-magnesian andesites.They were most likely derived from the partial melting of mantle peridotite caused by the addition of fluids released by subducted oceanic slab.Based on regional geology,geochemical characteristics and previous studies,we infer that the southward subduction of the Junggar Ocean slab resulted in the generation of early Paleozoic volcanic rocks and arc setting-related metallogenic systems in the Kalatag area. 展开更多
关键词 geodynamic setting VMS deposit petrogeochemistry Kalatag area East Tianshan
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A dual-period response of the Kuroshio Extension SST to Aleutian Low activity in the winter season 被引量:1
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作者 YU Peilong ZHANG Lifeng +2 位作者 LIU Hu LIU Xing ZHU Juan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第9期1-9,共9页
Based on our previous work, the winter sea surface temperature(SST) in the Kuroshio Extension(KE) region showed significant variability over the past century with periods of ~6 a between 1930 and 1950 and ~10 a be... Based on our previous work, the winter sea surface temperature(SST) in the Kuroshio Extension(KE) region showed significant variability over the past century with periods of ~6 a between 1930 and 1950 and ~10 a between1980 and 2009. How the activity of the Aleutian Low(AL) induces this dual-period variability over the two different timespans is further investigated here. For the ~6 a periodicity during 1930–1950, negative wind stress curl(WSC)anomalies in the central subtropical Pacific associated with an intensified AL generate positive sea surface height(SSH) anomalies. When these wind-induced SSH anomalies propagate westwards to the east of Taiwan, China two years later, positive velocity anomalies appear around the Kuroshio to the east of Taiwan and then the mean advection via this current of velocity anomalies leads to a strengthened KE jet and thus an increase in the KE SST one year later. For the ~10 a periodicity during 1980–2009, a negative North Pacific Oscillation-like dipole takes2–3 a to develop into a significant positive North Pacific Oscillation-like dipole, and this process corresponds to the northward shift of the AL. Negative WSC anomalies associated with this AL activity in the central North Pacific are able to induce the positive SSH anomalies. These oceanic signals then propagate westward into the KE region after 2–3 a, favoring a northward shift of the KE jet, thus leading to the warming of the KE SST. The feedbacks of the KE SST anomaly on the AL forcing are both negative for these two periodicities. These results suggest that the dual-period KE SST variability can be generated by the two-way KE-SST-AL coupling. 展开更多
关键词 sea surface temperature Kuroshio Extension Aleutian Low activity dual-period variability
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Vegetation Mapping for Regional Ecological Research and Management: A Case of the Loess Plateau in China 被引量:1
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作者 LIU Yuanxin LYU Yihe +2 位作者 BAI Yingfei ZHANG Buyun TONG Xiaolin 《Chinese Geographical Science》 SCIE CSCD 2020年第3期410-426,共17页
Vegetation maps are fundamental for regional-scale ecological research. However, information is often not sufficiently up to date for such research. The Loess Plateau is a key area for vegetation restoration projects ... Vegetation maps are fundamental for regional-scale ecological research. However, information is often not sufficiently up to date for such research. The Loess Plateau is a key area for vegetation restoration projects and a suitable area for regional ecological research. To carry out regional vegetation mapping based on the principles of hierarchical classification, object-oriented methods, visual interpretation, and accuracy assessment, this study integrated land cover, high-resolution remote sensing images, background environmental data, bioclimate zoning data, and field survey data from the Loess Plateau. To further clarify the implications of vegetation mapping, we compared the deviation of the 2015 vegetation map of the Loess Plateau(VMLP) and the widely used vegetation map of China(VMC)(1 : 1 000 000) for the expressed vegetation information and the evaluation of ecosystem services. The results indicated that 1) the vegetation of the Loess Plateau could be divided into 9 vegetation type groups and 18 vegetation types with classification accuracies of 87.76% and 83.97%, respectively;2) the distribution of vegetation had obvious zonal regularity;3) a deviation of 29.56 × 10^4 km^2 occurred when the vegetation coverage area was quantified with the VMC;4) the vegetation classification accuracy affected the ecosystem service assessment, the total water yield of the Loess Plateau calculated by the VMC and other required parameters was overestimated by 2.2 × 10^6 mm in 2015. Because vegetation mapping is a basic and important activity, that requires greater attention, this study provides supporting data for subsequent multivariate vegetation mapping and vegetation management for conservation and restoration. 展开更多
关键词 vegetation map Loess Plateau spatial pattern vegetation classification ecosystem service
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Fishery analysis using gradient-dependent optimal interpolation 被引量:1
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作者 Chunling Zhang Danyang Wang Zhenfeng Wang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2022年第2期116-126,共11页
The current lack of high-precision information on subsurface seawater is a constraint in fishery research.Based on Argo temperature and salinity profiles,this study applied the gradient-dependent optimal interpolation... The current lack of high-precision information on subsurface seawater is a constraint in fishery research.Based on Argo temperature and salinity profiles,this study applied the gradient-dependent optimal interpolation to reconstruct daily subsurface oceanic environmental information according to fishery dates and locations.The relationship between subsurface information and matching yellowfin tuna(YFT)in the western and central Pacific Ocean(WCPO)was examined using catch data from January 1,2008 to August 31,2017.The seawater temperature and salinity results showed differences of less than±0.5°C and±0.01 compared with the truth observations respectively.Statistical analysis revealed that the most suitable temperature for YFT fishery was 28–29°C at the near-surface.The most suitable salinity range for YFT fishery was 34.5–36.0 at depths shallower than 300 m.The suitable upper and lower bounds on the depths of the thermocline were 90–100 m and 300–350 m,respectively.The thermocline characteristics were prominent,with a mean temperature gradient exceeding 0.08°C/m.These results indicate that the profiles constructed by gradient-dependent optimal interpolation were more accurate than those of the nearest profiles adopted. 展开更多
关键词 gradient-dependent optimal interpolation YFT Argo profiles WCPO
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Genetic relationships among sympatric varieties of Acer mono in the Chichibu Mountains and Central Hokkaido, Japan 被引量:1
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作者 Chunping Liu Jian Cong +3 位作者 Hailong Shen Cunxue Lin Yoko Saito Yuji Ide 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第4期699-704,共6页
Acer mono Maxim. is one of the major components of cool temperate forests in Japan. Some of its many varieties are distributed sympatrically. Because of its great variability, the intraspecific taxonomy and nomenclatu... Acer mono Maxim. is one of the major components of cool temperate forests in Japan. Some of its many varieties are distributed sympatrically. Because of its great variability, the intraspecific taxonomy and nomenclature of the species are controversial. To understand the genetic relationships among these varieties and whether hybridization or introgression occurred among the sympatric varieties, we studied the genetic relationships among sympatric varieties of A. mono in the Chichibu Mountains (A. mono var. ambiguum, A. mono var. connivens, A. mono var. marmoratum) and Central Hokkaido (A. mono var. mayrii and A. mono var. glabrum) in Japan. Our results showed that varieties in Chichibu are genetically close, suggesting that hybridization or introgression might occur between these varieties, which could explain the higher genetic diversity of varieties in Chichibu than in Hokkaido. In contrast to the close relationships between the varieties in Chichibu, varieties in Hokkaido seemed relatively separated from each other; indeed, there may be reproductive isolation between the two varieties. The results provide new insight for the taxonomy of the varieties of A. mono, especially the sympatric varieties, in Japan. 展开更多
关键词 Genetic differentiation HYBRIDIZATION INTROGRESSION MAPLE nSSR
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Modeling Indicator Systems for Evaluating Environmental Sustainable Development Based on Factor Analysis 被引量:1
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作者 WU Hao CHEN Xiaoling +3 位作者 HE Ying HE Xiaorong CAI Xiaobin XU Keya 《Wuhan University Journal of Natural Sciences》 CAS 2006年第4期997-1002,共6页
Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the paramete... Indicator systems of environmental sustainable development in the Poyang Lake Basin are established from 51 elementary indexes by factor analysis, which is composed of four steps such as the factor model, the parameter estimation, the factor rotation and the factor score. Under the condition that the cumulative proportion is greater than 85%, 5 explicit factors of environmental sustainable development as well as its factor score by region are carried out. The result indicates some impact factors to the basin environmental in descending sort order are volume of water, volume of waste gas discharge,volume of solid wasters.the degree to comprehensive utilization of waste gas, waste water and solid wastes, the emission volume of waste gas, waste water and solid wastes. It is helpful and important to provide decision support for constituting sustainable development strategies and evaluate the sustainable development status of each city. 展开更多
关键词 factor analysis the Poyang Lake Basin environment evaluation sustainable development indicator systems
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