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Initial Exploration on Eco-environmental Issues in Tibet “One River and Two Streams” Agricultural Basin during New Period
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作者 ZHANG Huaguo 《Journal of Landscape Research》 2017年第1期57-60,共4页
Agricultural economic development of Tibet Autonomous Region mainly concentrates in the "One River and Two Streams" agricultural production basin. The basin is main concentrated place for agricultural resour... Agricultural economic development of Tibet Autonomous Region mainly concentrates in the "One River and Two Streams" agricultural production basin. The basin is main concentrated place for agricultural resources development,economic construction and population aggregation,and the region playing the advantages of Tibetan agriculture,corresponding with the practice,and enhancing self development and innovation. In the multi-year development and construction,it develops regional large agriculture,builds irrigation and water conservancy facilities,vigorously changes medium and low-yield land,actively develops animal husbandry and agriculture,and gradually promotes the effective combination of traffic industry and transportation industry,which has made considerable achievements. But in the face of today's increasingly advocated theme of "building beautiful Tibet and constructing ecological home",the construction of environmental problems lacking the systemic research is the prominent and fundamental problem in the "One River and Two Streams" agricultural production basin. Meanwhile,environment construction is an important part of economic development planning,and the solving of environmental protection problem is the historical mission in the contemporary and future generations. Therefore,it is very necessary to study the environment problems in Tibet "One River and Two Streams" agricultural production basin. The "One River and Two Streams" agricultural production basin is preliminarily explored for providing reference for the relevant environmental departments. 展开更多
关键词 "one river and Two Streams" Agriculture Eco-environment Initial exploration
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The Ecological Environment Problems and Countermeasures of Resources Development and Economy Development in Tibet "One River and Two Streams" Agricultural Ecological Basin during the New Period
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作者 Zhang Huaguo 《Meteorological and Environmental Research》 CAS 2017年第4期25-28,33,共5页
The integrated development of Tibet "one river and two streams" agricultural ecological basin should control the generated environmental problems and prevent new environmental problems,thereby promoting coor... The integrated development of Tibet "one river and two streams" agricultural ecological basin should control the generated environmental problems and prevent new environmental problems,thereby promoting coordinated development of agricultural economy in the region. It is very necessary and urgent to explore main environmental problems of Tibet " one river and two streams" agricultural ecological basin and effective countermeasures. When developing resources and economy,the principle of combining prevention with control,dominated by prevention and integrated control should be followed; regional advantages,characteristics and environmental self restoring ability should be sufficiently played and used; the policy of integrated prevention and utilization should be used; compensation method,prevention control measures and planning assumption for main environmental problems should be proposed,which could prevent that systemic development of Tibet " one river and two streams" agricultural ecological basin takes the old path of " firstly destroying and then controlling". 展开更多
关键词 "one river and two streams" ECOLOGICAL environment Problem COUNTERMEASURE
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Problems in the Development of Plateau Modern Agriculture in Tibet“One River and Two Streams”Agroecological Basin and Countermeasures
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作者 Zhang Huaguo 《Meteorological and Environmental Research》 CAS 2017年第2期90-94,共5页
Tibet Autonomous Region is located in the southwest of China. As a special area with high altitude,low temperature,abundant and diverse resources,the development of agricultural modernization has itself development at... Tibet Autonomous Region is located in the southwest of China. As a special area with high altitude,low temperature,abundant and diverse resources,the development of agricultural modernization has itself development attribute and feature. Agricultural development area of Tibet mainly concentrates in the " one river and two streams" basin. In this paper,combining the development of modern agriculture on the plateau,the connotation and characteristics of the development of plateau modern agriculture are illustrated from the angle of environment economics. Based on the observation method,linking theory with practice and combining literature research method,descriptive study is conducted,and the specific problems in the development of plateau modern agriculture in the agricultural basin are found. For example,the development of agriculture in Tibet has low utilization rate of resources and unbalanced distribution,agricultural mechanization shows gradient development,productivity and agricultural extension are backward,efforts to promote innovation and science knowledge are not enough,agricultural pollution expands,and the awareness of environmental protection is low. In view of the above problems,we put forward some countermeasures and suggestions: developing local advantage characteristic agriculture,developing cooperative economic organization,establishing the training promotion mode of theory combining with practice,establishing agricultural industry system of sightseeing tourism ecology. The research could provide theoretical suggestions for the future development of plateau modern agriculture. 展开更多
关键词 one river and two STREAMS Development PLATEAU modern AGRICULTURE COUNTERMEASURES China
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An Analysis of Labor Resources “One River and Two Tributaries” Region in Tibet, China
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作者 PENGChuan-zhong LIXiang-mei +1 位作者 LIUJian ZHONGXiang-hao 《Wuhan University Journal of Natural Sciences》 CAS 2005年第4期751-758,共8页
Focusing on the region of Yarlung Zangbo River and the middle reaches of its two tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the “One River and Two Tributaries” region), and based... Focusing on the region of Yarlung Zangbo River and the middle reaches of its two tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the “One River and Two Tributaries” region), and based on the data from China 3rd, 4th and 5th population censuses, the article has analyzed change patterns of this region’s labor force. Major findings from the study are summarized as follows: ① Compared with the data from the 3rd census, labor force population in 2000 has increased significantly. ② Children dependency coefficient has dropped, while old people dependency coefficient has changed very slightly with an increase of 0.047% only. ③ Compared 2000 with 1982, illiteracy and semi-illiteracy rate of the population above 15 years old have decreased significantly by 30.69 percentage points, but still higher than the national average. ④ Women’s illiteracy rate has dropped faster than men’s, but up to 2000 it was generally quite high. The upgrading of the entire population’s overall quality has a long way to go. 展开更多
关键词 中国 西藏 劳动力资源 依赖系数 教育水平 经济水平
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Yellowstone Region Drainage History as Determined from the 1955 Ashton, Idaho, Montana, and Wyoming 1:250,000 Scale Topographic Map, USA
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作者 Eric Clausen 《Open Journal of Geology》 CAS 2024年第3期317-338,共22页
The United States Geological Survey (USGS) 1955 (revised in 1972) Ashton topographic map (Ashton map) with a 1:250,000 scale and a 200-foot (about 60-meter) contour interval covers almost all of Yellowstone National P... The United States Geological Survey (USGS) 1955 (revised in 1972) Ashton topographic map (Ashton map) with a 1:250,000 scale and a 200-foot (about 60-meter) contour interval covers almost all of Yellowstone National Park and some adjacent regions to the south and west. In spite of numerous publications discussing Yellowstone region geologic history the drainage system and erosional landform evidence on the Ashton map appears to have been ignored. Drainage divides identifiable on the Ashton map separate the north-oriented Yellowstone, Gallatin, Madison, and Jefferson River drainage basins (which are located to the north and east of the continental divide with their water flowing to the Missouri River and ultimately the Gulf of Mexico) from the south-oriented Snake River drainage basin (with its water eventually reaching the Pacific Ocean). The Ashton map shows water-eroded passes and through valleys which link diverging and converging valleys which drain in opposite directions from the continental divide. These diverging and converging valleys suggest large volumes of south-oriented water once flowed across the Yellowstone region continental divide and some other Ashton map drainage divides. The accepted geology and glacial history paradigm (accepted paradigm) cannot satisfactorily explain the Ashton map drainage system and erosional landform evidence, which may be why geomorphologists have never addressed the map evidence. A new and fundamentally different geology and glacial history paradigm requiring the Yellowstone region to be located on the rim of a continental ice sheet created and occupied deep “hole” (which was uplifted as immense meltwater floods flowed across it) explains Ashton map drainage system and erosional landform evidence, but raises questions about previously published Yellowstone region geologic histories. 展开更多
关键词 Continental Divide Firehole river Gallatin river GEOMORPHOLOGY Madison river Snake river
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Adaptive interaction driven by the learning effect in the spatial prisoner's dilemma
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作者 李佳奇 张建磊 刘群 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期160-169,共10页
We propose a computing model in which individuals can automatically adjust their interaction intensity with their mentor according to the learning effect.This model is designed to investigate the cooperative dynamics ... We propose a computing model in which individuals can automatically adjust their interaction intensity with their mentor according to the learning effect.This model is designed to investigate the cooperative dynamics of the spatial prisoner's dilemma.More specifically,when the cumulative payoff of a learner is more than his reference earning,he will strengthen his interaction with his mentor;otherwise,he will reduce it.The experimental results indicate that this mechanism can improve the emergence of cooperation in a networked population and that the driving coefficient of interaction intensity plays an important role in promoting cooperation.Interestingly,under a certain social dilemma condition,there exists a minimal driving coefficient that leads to optimal cooperation.This occurs due to a positive feedback effect between the individual's satisfaction frequency and the number of effective neighbors.Moreover,we find that the experimental results are in accord with theoretical predictions obtained from an extension of the classical pair-approximation method.Our conclusions obtained by considering relationships with mentors can provide a new perspective for future investigations into the dynamics of evolutionary games within structured populations. 展开更多
关键词 self-adapting interaction evolutionary game MENTOR spatial prisoner's dilemma
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MF2-DMTD: A Formalism and Game-Based Reasoning Framework for Optimized Drone-Type Moving Target Defense
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作者 Sang Seo Jaeyeon Lee +2 位作者 Byeongjin Kim Woojin Lee Dohoon Kim 《Computers, Materials & Continua》 SCIE EI 2023年第11期2595-2628,共34页
Moving-target-defense(MTD)fundamentally avoids an illegal initial compromise by asymmetrically increasing the uncertainty as the attack surface of the observable defender changes depending on spatial-temporal mutation... Moving-target-defense(MTD)fundamentally avoids an illegal initial compromise by asymmetrically increasing the uncertainty as the attack surface of the observable defender changes depending on spatial-temporal mutations.However,the existing naive MTD studies were conducted focusing only on wired network mutations.And these cases have also been no formal research on wireless aircraft domains with attributes that are extremely unfavorable to embedded system operations,such as hostility,mobility,and dependency.Therefore,to solve these conceptual limitations,this study proposes normalized drone-type MTD that maximizes defender superiority by mutating the unique fingerprints of wireless drones and that optimizes the period-based mutation principle to adaptively secure the sustainability of drone operations.In addition,this study also specifies MF2-DMTD(model-checkingbased formal framework for drone-type MTD),a formal framework that adopts model-checking and zero-sum game,for attack-defense simulation and performance evaluation of drone-type MTD.Subsequently,by applying the proposed models,the optimization of deceptive defense performance of drone-type MTD for each mutation period also additionally achieves through mixed-integer quadratic constrained programming(MIQCP)and multiobjective optimization-based Pareto frontier.As a result,the optimal mutation cycles in drone-type MTD were derived as(65,120,85)for each control-mobility,telecommunication,and payload component configured inside the drone.And the optimal MTD cycles for each swarming cluster,ground control station(GCS),and zone service provider(ZSP)deployed outside the drone were also additionally calculated as(70,60,85),respectively.To the best of these authors’knowledge,this study is the first to calculate the deceptive efficiency and functional continuity of the MTD against drones and to normalize the trade-off according to a sensitivity analysis with the optimum. 展开更多
关键词 Moving-target-defense(MTD) DRone formal methods game theory
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Intelligent BCI Headphone for a Healthier and a Deeper Immersive Gameplay
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作者 Ilman Shazhaev Dmitry Mikhaylov Abdulla Shafeeg 《International Journal of Intelligence Science》 2023年第2期23-32,共10页
The developments in the area of brain research by analysing brain activity of individuals have given rise to many useful applications, such as diagnosing mental disorders more efficiently, treatment of cognitive disor... The developments in the area of brain research by analysing brain activity of individuals have given rise to many useful applications, such as diagnosing mental disorders more efficiently, treatment of cognitive disorders, and developing of brain-computer interfaces for treatment, communication and entertainment purposes. However, the development of such applications is hindered by a shortage of easy-to-use and comfortable sensors, as well as a lack of high-quality brain activity data. In the first part of this paper, a review of the status of BCI applications is presented followed by a proposal of a framework for developing an intelligent BCI headphone that takes leverages of the huge amount of data coming from playing video games to let the players experience a full immersive gaming experience. 展开更多
关键词 BCI Immersive Gaming Artificial Intelligence VIDEOgameS HEALTH
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A cooperative detection game:UAV swarm vs.one fast intruder
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作者 XIAO Zhiwen FU Xiaowei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1565-1575,共11页
This paper studies a special defense game using unmanned aerial vehicle(UAV)swarm against a fast intruder.The fast intruder applies an offensive strategy based on the artificial potential field method and Apollonius c... This paper studies a special defense game using unmanned aerial vehicle(UAV)swarm against a fast intruder.The fast intruder applies an offensive strategy based on the artificial potential field method and Apollonius circle to scout a certain destination.As defenders,the UAVs are arranged into three layers:the forward layer,the midfield layer and the back layer.The co-defense mechanism,including the role derivation method of UAV swarm and a guidance law based on the co-defense front point,is introduced for UAV swarm to co-detect the intruder.Besides,five formations are designed for comparative analysis when ten UAVs are applied.Through Monte Carlo experiments and ablation experiment,the effectiveness of the proposed co-defense method has been verified. 展开更多
关键词 cooperative detection game unmanned aerial vehicle(UAV)swarm fast intruder defensive strategy co-defense mechanism.
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Multiple grain-size fraction analysis of heavy minerals and the provenance identification of sediments from the abandoned Huanghe River,eastern China
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作者 Mengyao WANG Bingfu JIN Jianjun JIA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期921-935,共15页
The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrita... The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrital grains,provide a reliable provenance-tracing approach.We developed a mineral identification method to analyze the multiple grain-size fraction of sediments,from which the elemental geochemistry of hornblende was used to compare the characteristics of sediments from the Huaihe River and Huanghe(Yellow)River in eastern China.Elements that were statistically identified as being able to discriminate sediment provenance were employed to perform a quantitative analysis of the sources of sediments of the abandoned Huanghe River.Results reveal that the Huaihe River is characterized by a high amphibole content of>60%and that the Huanghe and abandoned Huanghe rivers have greater abundances of limonite and carbonate minerals compared with those of the Huaihe River.The contents of trace elements and rare earth elements in hornblende show that the sediments of the abandoned Huanghe River are similar to those of the Huanghe River but different from those of the Huaihe River.Furthermore,chemical mass balance was used to calculate the relative contributions of different provenances of sediment from the abandoned Huanghe River,and nine trace elements of hornblende were identified as discriminators of provenance.Approximately 2%of the hornblende in the abandoned Huanghe River is derived from the Huaihe River and 98%from the Huanghe River.Considering the proportion of hornblende in the total sediment,it is inferred that the contribution of Huaihe River sediment to the abandoned Huanghe River is approximately 0.5%.This study shows that mineral analysis using multiple grain-size fractions(within the wide range of 1Φto 6Φ)with assessment in elemental geochemistry of hornblende can characterize the provenance of fluvial material in coastal zones. 展开更多
关键词 quantitative provenance analysis heavy mineral multiple grain-size fraction HORNBLENDE elemental geochemistry fluvial sediment the abandoned Huanghe river
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Study on strength properties and soil behaviour type classification of Huanghe River Delta silts based on variable rate piezocone penetration test
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作者 Yunuo Liu Guoqing Lin +3 位作者 Yan Zhang Shenggui Deng Lei Guo Tao Liu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期146-158,共13页
Fine-grained silt is widely distributed in the Huanghe River Delta(HRD)in China,and the sedimentary structure is complex,meaning that the clay content in the silt is variable.The piezocone penetration test(CPTu)is the... Fine-grained silt is widely distributed in the Huanghe River Delta(HRD)in China,and the sedimentary structure is complex,meaning that the clay content in the silt is variable.The piezocone penetration test(CPTu)is the most widely approved in situ test method.It can be used to invert soil properties and interpret soil behavior.To analyse the strength properties of surface sediments in the HRD,this paper evaluated the friction angle and its inversion formula through the CPTu penetration test and monotonic simple shear test and other soil unit experiments.The evaluation showed that the empirical formula proposed by Kulhawy and Mayne had better prediction and inversion effect.The HRD silts with clay contents of 9.2%,21.4%and 30.3%were selected as samples for the CPTu variable rate penetration test.The results show as follows.(1)The effects of the clay content on the tip resistance and the pore pressure of silt under different penetration rates were summarized.The tip resistance Q_t is strongly dependent on the clay content of the silt,the B_(q)value of the silt tends to 0 and is not significantly affected by the change of the CPTu penetration rate.(2)Five soil behavior type classification charts and three soil behavior type indexes based on CPTu data were evaluated.The results show that the soil behavior type classification chart based on soil behavior type index ISBT,the Robertson 2010 behavior type classification chart are more suitable for the silty soil in the HRD. 展开更多
关键词 Huanghe river Delta piezocone penetration test silty soils clay content friction angle soil behaviour type classification
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Genetic progress in stem lodging resistance of the dominant wheat cultivars adapted to Yellow-Huai River Valleys Winter Wheat Zone in China since 1964 被引量:7
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作者 ZHANG Hong-jun LI Teng +9 位作者 LIU Hong-wei MAI Chun-yan YU Guang-jun LI Hui-li YU Li-qiang MENG Ling-zhi JIAN Da-wei YANG Li LI Hong-jie ZHOU Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第2期438-448,共11页
Analysis of genetic progress for lodging-related traits provides important information for further improvement of lodging resistance.Forty winter wheat cultivars widely grown in the Yellow-Huai River Valleys Winter Wh... Analysis of genetic progress for lodging-related traits provides important information for further improvement of lodging resistance.Forty winter wheat cultivars widely grown in the Yellow-Huai River Valleys Winter Wheat Zone(YHWZ)of China during the period of 1964–2015 were evaluated for several lodging-related traits in three cropping seasons.Plant height,height at center of gravity,length of the basal second internode,and lodging index decreased significantly in this period,and the average annual genetic gains for these traits were–0.50 cm or–0.62%,–0.27 cm or–0.60%,–0.06 cm or–0.63%,and–0.01 or–0.94%,respectively.Different from other traits,stem strength showed a significant increasing trend with the breeding period,and the annual genetic gains were 0.03 N or 0.05%.Correlation analysis showed that lodging index was positively correlated with plant height,height at center of gravity,and length of the basal second internode,but negatively correlated with stem strength.Meanwhile,significantly positive correlations were observed between plant height,height at center of gravity,and length of the basal first and second internodes.By comparison with the wild types,dwarfing genes had significant effects on all lodging-related traits studied except for length of the basal first internode and stem strength.Principle component analysis demonstrated that plant height and stem strength were the most important factors influencing lodging resistance.Clustering analysis based on the first two principle components further indicated the targets of wheat lodging-resistant breeding have changed from reducing plant height to strengthening stem strength over the breeding periods.This study indicates that the increase of stem strength is vital to improve lodging resistance in this region under the high-yielding condition when plant height is in an optimal range. 展开更多
关键词 Triticum aestivum lodging resistance stem strength genetic progress Yellow-Huai river Valleys Winter Wheat Zone
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Restoration processes of pollution zones in Hanjiang River 被引量:2
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作者 Shen Yunfen Tan Yuyun +1 位作者 Feng Weisong Gu Manru (Institute of Hydrobiology, Chinese Academy of Sciences, Wuchang 430072, China) He Chengying (Environmental Protection Station of Xiantao City ,China) Li Aiguo (Environmental Protection Station of Xiangfan Ci 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第2期178-184,共7页
RestorationprocessesofpollutionzonesinHanjiangRiver¥ShenYunfen;TanYuyun;FengWeisong;GuManru(InstituteofHydro... RestorationprocessesofpollutionzonesinHanjiangRiver¥ShenYunfen;TanYuyun;FengWeisong;GuManru(InstituteofHydrobiology,ChineseAc... 展开更多
关键词 RESTORATION process MICROBIAL COMMUNITY BIOMONITORING river POLLUTION zone.
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THE OPTIMAL CONTROL FOR PROMOTING THE COOPERATION IN EVOLUTION GAME GENERATED BY PRISONER'S DILEMMA 被引量:2
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作者 王先甲 董瑞 陈琳 《Acta Mathematica Scientia》 SCIE CSCD 2018年第1期73-92,共20页
Natural selection opposes the evolution of cooperation unless specific mechanisms are at work in Prisoner's Dilemma. By taking advantage of the modern control theory, the controller design is discussed and the opt... Natural selection opposes the evolution of cooperation unless specific mechanisms are at work in Prisoner's Dilemma. By taking advantage of the modern control theory, the controller design is discussed and the optimal control is designed for promoting cooperation based on the recent advances in mechanisms for the evolution of cooperation. Two control strategies are proposed: compensation control strategy for the cooperator when playing against a defector and reward control strategy for cooperator when playing against a cooperator. The feasibility and effectiveness of these control strategies for promoting cooperation in different stages are analyzed. The reward for cooperation can't prevent defection from being evolutionary stable strategy(ESS). On the other hand, compensation for the cooperator can't prevent defection from emerging and sustaining. By considering the effect and the cost, an optimal control scheme with constraint on the admissible control set is put forward.By analyzing the special nonlinear system of replicator dynamics, the exact analytic solution of the optimal control scheme is obtained based on the maximum principle. Finally, the effectiveness of the proposed method is illustrated by examples. 展开更多
关键词 evolutionary games Prisoner’s Dilemma evolution of cooperation promoting cooperation control optimal control
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基于River 2D模型的黄河花园口河段生态流量研究
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作者 龙瑞昊 马永胜 +1 位作者 任姗 雷凯旋 《水利与建筑工程学报》 2024年第1期213-219,共7页
针对目前生态流量研究方法难以充分考虑鱼类栖息地等生境因素的问题,以黄河花园口鲤鱼核心保护区为研究区域,选取黄河鲤鱼为研究物种,基于耦合水动力学模型和栖息地模型的River 2D模型确定黄河鲤鱼的生态流量,将水深和流速作为鱼类生存... 针对目前生态流量研究方法难以充分考虑鱼类栖息地等生境因素的问题,以黄河花园口鲤鱼核心保护区为研究区域,选取黄河鲤鱼为研究物种,基于耦合水动力学模型和栖息地模型的River 2D模型确定黄河鲤鱼的生态流量,将水深和流速作为鱼类生存保护的限定性因子,采用栖息地模型模拟不同流量下对应的黄河鲤鱼的适宜栖息地面积。计算结果表明:花园口河段鲤鱼产卵期的最小生态流量为230 m^(3)/s,生长期的最小生态流量为430 m^(3)/s,越冬期的最小生态流量为150 m^(3)/s。计算结果可以为花园口核心鱼类保护区的鱼类保护以及黄河小浪底水库的生态调度提供参考。 展开更多
关键词 生态流量 river 2D模型 栖息地 加权可用面积 黄河鲤鱼
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Geological Features of the Eastern Sector of the Bangong Co-Nujiang River Suture Zone:Tethyan Evolution 被引量:10
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作者 WANG Jianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期229-235,共7页
According to an analysis of the geological features in the eastern sector of the Bangong Co-Nujiang River suture zone, the Tethyan evolution can be divided into three stages. (1) The Embryo-Tethyan stage (Pz1): An imm... According to an analysis of the geological features in the eastern sector of the Bangong Co-Nujiang River suture zone, the Tethyan evolution can be divided into three stages. (1) The Embryo-Tethyan stage (Pz1): An immature volcanic arc developed in Taniantaweng (Tanen Taunggyi) Range, indicating the existence of an Embryo-Tethyan ocean. (2) The Palaeo-Tethyan stage (C-T2): During the Carboniferous the northern side of the Taniantaweng Range was the main domain of the Pa-laeo-Tethyan ocean, in which developed flysch sediments intercalated with bimodal volcanic rocks and oceanic tholeiite, and Pemian-Early Triassic arc granites were superimposed on the Taniantaweng magmatic arc; on the southern side the Dengqen-Nujiang zone started secondary extension during the Carboniferous, in which the Nujiang ophiolite developed, and the Palaeo-Tethyan ocean closed before the Middle Triassic. (3) The Neo-Tethyan stage (T3-E): During the Late Triassic the Dengqen zone developed into a relatively matural ocean basin, 展开更多
关键词 Bangong Co-Nujiang river suture zone Tethyan evolution Embryo-Tethys Palaeo-Tethys NEO-TETHYS
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UNITED INTERNATIONAL CENTRAL CITY: A NEW SPATIAL ORGANIZATION MODEL IN TUMEN RIVER ECONOMY DEVELOPMENT ZONE 被引量:2
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作者 张平宇 《Chinese Geographical Science》 SCIE CSCD 1998年第4期83-89,共0页
I.INTRODUCTIONSince1980,NortheastAsiahasexperiencedarapidregionaleconomicunificationagainsteconomicglobaliza... I.INTRODUCTIONSince1980,NortheastAsiahasexperiencedarapidregionaleconomicunificationagainsteconomicglobalization.TheTumenRive... 展开更多
关键词 UNITED international CENTRAL city SPATIAL structure SPATIAL ORGANIZATION Tumen river ECONOMY Development Zone
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非对称Colonel Blotto博弈模型下的多信道功率分配抗干扰 被引量:1
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作者 魏鹏 王世练 +1 位作者 陆锐敏 骆俊杉 《国防科技大学学报》 EI CAS CSCD 北大核心 2023年第1期35-48,共14页
针对智能干扰条件下传输速率固定的通信系统多信道功率分配问题,建立了非对称Colonel Blotto博弈模型。在完全信息条件下,推导出了各种功率预算约束下通信方和干扰方的等效单信道最优功率分配策略,进而证明了通信方和干扰方存在唯一混... 针对智能干扰条件下传输速率固定的通信系统多信道功率分配问题,建立了非对称Colonel Blotto博弈模型。在完全信息条件下,推导出了各种功率预算约束下通信方和干扰方的等效单信道最优功率分配策略,进而证明了通信方和干扰方存在唯一混合纳什均衡策略,并求得了纳什均衡收益。基于等效单信道最优功率分布,提出了一种多重扫描直接列元素交换算法,可以快速构建多信道混合功率分配矩阵,且相比于线性规划方法,可适应更多的信道数和更广的功率分布范围。通过数值仿真,验证了所提多信道混合功率分配矩阵构造算法的有效性及多信道功率分配策略的最优性。 展开更多
关键词 非对称Colonel Blotto博弈 抗干扰 多信道功率分配 混合策略 纳什均衡
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Dynamic Analysis of Deformational Structures of the Xianniishan Fault Zone in the Three Gorges of the Yangtze River 被引量:1
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作者 WU Shuren Institute of Geomechanics,CAGS, Beijing 100081and WU Ganguo China University of Geosciences, Beijing 100083 Liu Xinzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第2期163-172,共10页
Field investigation and laboratory work reveal that inhomogeneity of the deformation of the Xiannushan fault is mainly characterized by lateral zonation, longitudinal segmentation and downward stratification. Based on... Field investigation and laboratory work reveal that inhomogeneity of the deformation of the Xiannushan fault is mainly characterized by lateral zonation, longitudinal segmentation and downward stratification. Based on these results, a 3-D deformational structure model of the fault was established and its geometrical and kinematic characteristics in two main deformational stages i.e. the main Yanshanian and Himalayan were discussed. The directions of principal and the differential stresses in these two stages were determined by using conjugate joints, striations of fault planes and microstructures of the fault zone. The direction of σI is N-S in direction with differential stresses of 150-250 MPa in the Yanshanian, and N70E with a differential stress ranging from 80-120 MPa in the Himalayan. 展开更多
关键词 three gorges of the YANGTZE river Xiannushan FAULT FAULT DEFORMATION structure differential stress
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Records of bulk organic matter and plant pigments in sediment of the "red-tide zone" adjacent to the Changjiang River estuary 被引量:1
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作者 亢振军 于仁成 +5 位作者 孔凡洲 王云峰 高岩 陈建华 郭伟 周名江 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第5期915-927,共13页
Cultural eutrophication caused by nutrient over-enrichment in coastal waters will lead to a cascading set of ecosystem changes and deleterious ecological consequences,such as harmful algal blooms(HABs) and hypoxia.Dur... Cultural eutrophication caused by nutrient over-enrichment in coastal waters will lead to a cascading set of ecosystem changes and deleterious ecological consequences,such as harmful algal blooms(HABs) and hypoxia.During the past two decades since the late 1990s,recurrent large-scale HABs(red tides)and an extensive hypoxic zone have been reported in the coastal waters adjacent to the Changjiang River estuary.To retrieve the history of eutrophication and its associated ecosystem changes,a sediment core was collected from the "red-tide zone" adjacent to the Changjiang River estuary.The core was dated using the^(210)Pb radioisotope and examined for multiple proxies,including organic carbon(OC),total nitrogen(TN),stable isotopes of C and N,and plant pigments.An apparent up-core increase of OC content was observed after the 1970s,accompanied by a rapid increase of TN.The concurrent enrichment of δ^(13)C and increase of the C/N ratio suggested the accumulation of organic matter derived from marine primary production during this stage.The accumulation of OC after the 1970 s well reflected the significant increase of primary production in the red-tide zone and probably the intensification of hypoxia as well.Plant pigments,including chlorophyll a,p-carotene,and diatoxanthin,showed similar patterns of variation to OC throughout the core,which further confirmed the important contribution of microalgae,particularly diatoms,to the deposited organic matter.Based on the variant profiles of the pigments representative of different microalgal groups,the potential changes of the phytoplankton community since the 1970s were discussed. 展开更多
关键词 EUTROPHICATION harmful algal bloom HYPOXIA PIGMENT sediment core Changjiang river estuary
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