|
|
|
题名
|
作者
|
年代
|
出处
|
被引量
|
| 1 | Plant phenological responses to climate change on the Tibetan Plateau: research status and challenges显示文摘Phenology studies the cycle of events in nature that are initiated and driven by an annually recurring environment. Plant phenology is expected to be one of the most sensitive and easily observable natural indicators of climate change. On the Tibetan Plateau(TP), an accelerated warming since the mid-1980 s has resulted in signiicant environmental changes. hese new conditions are accompanied by phenological changes that are characterized by considerable spatiotemporal heterogeneity. Satellite remote sensing observed widespread advance in the start of the plant growing season across the plateau during the 1980 s and 1990 s but substantial delay over 2000–2011 in the southwest although it continued to advance in the northeast regions of the TP. Both observational studies and controlled experiments have revealed, to some extent, the positive role of higher preseason temperature and even more precipitation in advancing the leaf onset and irst lowering date of the TP. However, a number of rarely visited research issues that are essential for understanding the role of phenology in ecosystem responses and feedback processes to climate change remain to be solved. Our review recommends that addressing the following questions should be a high priority. How did other phenological events change, such as lowering and fruiting phenology? What are the inluences from environmental changes other than temperature and precipitation, including human activities such as grazing? What are the genetic and physiological bases of plants phenological responses?How does phenological change inluence ecosystem structure and function at diferent scales and feedback to the climate system? Investigating these research questions requires, irst of all, new data of the associated environmental variables, and consistent and reliable phenological observation using diferent methodologies(i.e. in situ observations and remote sensing). | Miaogen Shen Shilong Piao Tsechoe Dorji Qiang Liu Nan Cong Xiaoqiu Chen Shuai An Shiping Wang Tao Wang Gengxin Zhang | 2015 | National Science Review2015，2，4： | 13 |
| 2 | COVERAGE PERFORMANCES ANALYSIS ON COMBINED-GEO-IGSO SATELLITE CONSTELLATION显示文摘The Combined-GEO-IGSO constellation is the combination of Geostationary Earth Orbit(GEO) satellite and Inclining GeoSynchronous Orbit(IGSO) satellite.The Combined-GEO-IGSO constellation can integrate the advantages of GEO and IGSO to achieve regional coverage.In order to discuss the performances of the Combined-GEO-IGSO constellation,the performances of coverage,elevation,diversity,and transmission are simulated in China and surrounding regions by Satellite Tool Kit(STK).The simulation results show that:the combined constellation can reach higher multi-satellite coverage and higher communication elevation in China and surrounding areas;the Doppler shift,delay,and propagation loss of this constellation have little impact on the system.As regional coverage constellation,the Combined-GEO-IGSO is feasible. | Jiang Yong Yang Sen Zhang Gengxin Li Guangxia | 2011 | Journal of Electronics(China)2011，28，2： | 12 |
| 3 | Discovery of carbonaceous compressions and their multicellular tissues from the Changzhougou Formation (1 800 Ma) in the Yanshan range, North China显示文摘In 1997 and 1998, hundreds of specimens of megascopic carbonaceous compressions or algal fossils were found from - 1800-million-year old Changzhougou Formation, which is the lowermost unit of the latest Palaeoproterozoic Changcheng Group (~1 600-1 800 Ma) in the Xinglong-Kuancheng areas at the middle Yanshan Range, North China. They are discoid, ellipsoid and sausage-like, namely shaped like Chuaria Shouhsiennia (Ellipsophyta) and Tawuia. By adopting HF acid-resistant maceration coupled with scanning electron microscope and petrologic section, the authors made a preliminary research on the histology for some circular and ellipsoid carbonaceous compressions, namely Chuaria- and Shouhsienia-llke forms, in addition to their morphology. The following three types of multicellular tissues have been found in the fragments of them: colony-like, pseudoparenchyma-like and parenchyma-like. All of the new data about multicelluar tissues not only supply a very important basis in histology to determine the | ZHU Shixing SUN Shufen HUANG Xueguang HE Yuzhen ZHU Gengxin SUN Lixin ZHANG Kuan | 2000 | Chinese Science Bulletin2000，45，9： | 10 |
| 4 | Spectrum Sensing via Temporal Convolutional Network显示文摘In this paper,we investigate a spectrumsensing system in the presence of a satellite,where the satellite works as a sensing node.Considering the conventional energy detection method is sensitive to the noise uncertainty,thus,a temporal convolutional network(TCN)based spectrum-sensing method is designed to eliminate the effect of the noise uncertainty and improve the performance of spectrum sensing,relying on the offline training and the online detection stages.Specifically,in the offline training stage,spectrum data captured by the satellite is sent to the TCN deployed on the gateway for training purpose.Moreover,in the online detection stage,the well trained TCN is utilized to perform real-time spectrum sensing,which can upgrade spectrum-sensing performance by exploiting the temporal features.Additionally,simulation results demonstrate that the proposed method achieves a higher probability of detection than that of the conventional energy detection(ED),the convolutional neural network(CNN),and deep neural network(DNN).Furthermore,the proposed method outperforms the CNN and the DNN in terms of a lower computational complexity. | Tao Ni Xiaojin Ding Yunfeng Wang Jun Shen Lifeng Jiang Gengxin Zhang | 2021 | China Communications2021，18，9： | 6 |
| 5 | BLIND SYMBOL RATE ESTIMATION OF SATELLITE COMMUNICATION SIGNAL BY HAAR WAVELET TRANSFORM显示文摘As the raised cosine shaping filter is often employed in practical satellite communication system,the envelope fluctuation at the symbol transition point is decreased which leads to the failure of the common wavelet algorithm under low SNR.Accordingly,a method of blind symbol rate estimation using signal preprocessing and Haar wavelet is proposed in this paper.Firstly,the effect of filter shaping can be reduced by the signal preprocessing.Then,the optimal scale factor is searched and the signal is processed and analyzed by the Haar wavelet transform.Finally,the symbol rate line is extracted and a nonlinear filter method is inducted for improving the estimation performance.Theoretical analysis and computer simulation show the efficiency of the proposed algorithm under low SNR and small roll-off factor. | Wang Long Zhang Gengxin Bian Dongming Xie Zhidong Hu Jing | 2011 | Journal of Electronics(China)2011，28，2： | 6 |
| 6 | Joint Precoding Schemes for Flexible Resource Allocation in High Throughput Satellite Systems Based on Beam Hopping显示文摘Beam hopping technology provides a foundation for the flexible allocation and efficient utilization of satellite resources,which is considered as a key technology for the next generation of high throughput satellite systems.To alleviate the contradiction between resource utilization and co-frequency interference in beam hopping technology,this paper firstly studies dynamic clustering to balance traffic between clusters and proposes cluster hopping pool optimization method to avoid inter-cluster interference.Then based on the optimization results,a novel joint beam hopping and precoding algorithm is provided to combine resource allocation and intra-cluster interference suppression,which can make efficient utilization of system resources and achieve reliable and near-optimal transmission capacity.The simulation results show that,compared with traditional methods,the proposed algorithms can dynamically adjust to balance demand traffic between clusters and meet the service requirements of each beam,also eliminate the co-channel interference to improve the performance of satellite network. | Chen Zhang Xudong Zhao Gengxin Zhang | 2021 | China Communications2021，18，9： | 5 |
| 7 | Application of the Gravity Method to the Iron Ore Exploration in Eastern Hebei Province显示文摘The nation-wide iron ore exploration is primarily based on aeromagnetic survey,based upon which a series of ground follow-up and drilling examination were carried out,and then reconnaissance and detailed investigation and exploration were fulfilled.However,for some large, | ZHANG Guoli ZHAO Gengxin HE Fuqing SU Yongjun TENG Fei KUANG Haiyang | 2015 | Acta Geologica Sinica(English Edition)2015，89，6： | 5 |
| 8 | Application of Multi-agent Models to Urban Expansion in Medium and Small Cities: A Case Study in Fuyang City,Zhejiang Province,China显示文摘In this study,three-phase satellite images were used to define rules for the allocation of time and space in construction land resources based on a complex adaptive system and game theory.The decision behavior and rules of government agent,enterprise agent and resident agent in construction land growth were explored.A distinctive and dynamic simulation model of construction land growth was built,which integrated multi-agent,GIS technology and RS data and described the interaction among influencing agents.Taking Fuyang City in the Changjiang River Delta as an example,an assessment process for the remote sensing data in construction land and scenario planning was constructed.Repast and ArcGIS were used as simulation platforms.A simulation of the spatial pattern in land-use planning and the setting of scenario planning were conducted by using the incomplete active game,which was based on different natural,social and economic levels.Through this model,a simulation of urban planning space and decision-making for Fuyang City was created.Relevant non-structured problems arising from urban planning management could be identified,and the process and logic of urban planning spatial decision-making could thus be improved.Cel1-by-cel1 comparison showed that the simulation accuracy was over 72%.This model has great potential for use by government and town planners in decision support and technique support in the policy-making process. | ZHANG Jing WANG Ke SONG Gengxin ZHANG Zhongchu CHEN Xinming YU Zhoulu | 2013 | Chinese Geographical Science2013，23，6： | 5 |
| 9 | A SURVEY OF DEEP SPACE COMMUNICATIONS显示文摘Deep space communications has played an important role in deep space exploration. Compared with common satellite and terrestrial communications, deep space communications faces more challenging environment. The paper investigated the unique features of deep space communica-tions in detail, discussed the key technologies and its development trends for deep space communica-tions. | Zhang Gengxin Xie Zhidong Bian Dongming Sun Qian | 2011 | Journal of Electronics(China)2011，28，2： | 3 |
| 10 | Upper Ocean Temperatures Hit Record High in 2020显示文摘The long-term warming of the ocean is a critical indicator of both the past and present state of the climate system. It also provides insights about the changes to come, owing to the persistence of both decadal variations and secular trends,which the ocean records extremely well(Hansen et al., 2011;IPCC, 2013;Rhein et al., 2013;Trenberth et al., 2016;Abram et al., 2019). | Lijing CHENG John ABRAHAM Kevin ETRENBERTH John FASULLO Tim BOYER Ricardo LOCARNINI Bin ZHANG Fujiang YU Liying WAN Xingrong CHEN Xiangzhou SONG Yulong LIU Michael EMANN Franco RESEGHETTI Simona SIMONCELLI Viktor GOURETSKI Gengxin CHEN Alexey MISHONOV Jim REAGAN Jiang ZHU | 2021 | Advances in Atmospheric Sciences2021，38，4： | 2 |
| 11 | Spectroscopic studies of dye-surfactant interactions with the co-existence of heavy metal ions for foam fractionation显示文摘The interaction between a cationic dye Methylene Blue(MB) and an anionic surfactant sodium dodecyl sulfate(SDS) with the presence of Cd2+ was investigated spectrophotometrically in a certain concentration range.The spectrophotometric measurements of dye-metal ion-surfactant system were carried out.The results indicated that the SDS concentration had a significant influence on the dye spectrum,while the addition of Cd2+ hardly caused change of the maximum value of absorbance.According to this observation,we concluded that electrostatic and hydrophobic interaction between dye and surfactant occurred up to a certain level,and the homo-ions Cd2+ almost exerted no effect on the dye-surfactant complexation,establishing a theoretical foundation for simultaneous removal of organic dye and heavy metal using foam fractionation.Meanwhile,the effects of their interaction on foam performance were investigated.The results showed that the addition of Cd2+ favored the tendency to ameliorate foam properties just contrary to MB.The feasibility of foam separation for dye and heavy metal removal from simulated wastewater was also confirmed using a continuous foam fractionator.In the simultaneous removal process,with the initial SDS concentration ranging from 0.5 to 5.0mmol/L,the maximum removal efficiencies of MB and Cd2+ were obtained as 99.69% and 99.61%,respectively.The enrichment ratios were reduced from24.34 to 7.65 for MB and from22.01 to 3.35 for Cd2+. | Dongmei Zhang Guangming Zeng Jinhui Huang Wenkai Bi Gengxin Xie | 2012 | Journal of Environmental Sciences2012，24，12： | 2 |
| 12 | Space-Terrestrial Integrated Architecture for Internet of Things显示文摘To realize the ultimate vision of Internet of Things(IoT),only depending on terrestrial network is far from enough.As a supplement and extension of terrestrial network,satellite network can offer powerful support to realize the depth and breadth of the coverage.However,existing satellite networks are usually designed for particular purposes.Moreover,traditional satellite networks and terrestrial networks are developed and operated separately,consequently they cannot meet the need of network flexibility required by IoT.In this paper,a space-terrestrial architecture is conceived for constructing a spaceterrestrial based IoT(ST-IoT) system.Additionally,a reliable identification procedure,an integrated access and communication procedure,as well as a clustering cooperative transmission strategy are also presented. | ZHANG Gengxin DING Xiaojin QU Zhicheng | 2020 | ZTE Communications2020，18，4： | 2 |
| 13 | Another Record: Ocean Warming Continues through 2021 despite La Nina Conditions显示文摘The increased concentration of greenhouse gases in the atmosphere from human activities traps heat within the climate system and increases ocean heat content(OHC). Here, we provide the first analysis of recent OHC changes through 2021 from two international groups. The world ocean, in 2021, was the hottest ever recorded by humans, and the 2021 annual OHC value is even higher than last year’s record value by 14 ± 11 ZJ(1 zetta J = 1021 J) using the IAP/CAS dataset and by16 ± 10 ZJ using NCEI/NOAA dataset. The long-term ocean warming is larger in the Atlantic and Southern Oceans than in other regions and is mainly attributed, via climate model simulations, to an increase in anthropogenic greenhouse gas concentrations. The year-to-year variation of OHC is primarily tied to the El Nino-Southern Oscillation(ENSO). In the seven maritime domains of the Indian, Tropical Atlantic, North Atlantic, Northwest Pacific, North Pacific, Southern oceans,and the Mediterranean Sea, robust warming is observed but with distinct inter-annual to decadal variability. Four out of seven domains showed record-high heat content in 2021. The anomalous global and regional ocean warming established in this study should be incorporated into climate risk assessments, adaptation, and mitigation. | Lijing CHENG John ABRAHAM Kevin ETRENBERTH John FASULLO Tim BOYER Michael EMANN Jiang ZHU Fan WANG Ricardo LOCARNINI Yuanlong LI Bin ZHANG Zhetao TAN Fujiang YU Liying WAN Xingrong CHEN Xiangzhou SONG Yulong LIU Franco RESEGHETTI Simona SIMONCELLI Viktor GOURETSKI Gengxin CHEN Alexey MISHONOV Jim REAGAN | 2022 | Advances in Atmospheric Sciences2022，39，3： | 1 |
| 14 | Stochastic Dynamic Modeling of Rain Attenuation: A Survey显示文摘Satellite communication systems(SCS) operating on frequency bands above 10 GHz are sensitive to atmosphere physical phenomena, especially rain attenuation. To evaluate impairments in satellite performance, stochastic dynamic modeling(SDM) is considered as an effective way to predict real-time satellite channel fading caused by rain. This article carries out a survey of SDM using stochastic differential equations(SDEs) currently in the literature. Special attention is given to the different input characteristics of each model to satisfy specific local conditions. Future research directions in SDM are also suggested in this paper. | Zhicheng Qu Gengxin Zhang Haotong Cao Jidong Xie | 2018 | China Communications2018，15，3： | 1 |
| 15 | The eddy pair off eastern Vietnam: Interannual variability and impact on thermohaline structure显示文摘 | Gengxin Chen Yijun Hou Qilong Zhang Xiaoqing Chu | 2009 | Continental Shelf Research2009，，7： | 1 |
| 16 | Microbial Diversity in Sediments of Saline Qinghai Lake, China: Linking Geochemical Controls to Microbial Ecology显示文摘 | Hailiang Dong Gengxin Zhang Hongchen Jiang Bingsong Yu Leah R. Chapman Courtney R. Lucas Matthew W. Fields | 2006 | Microbial Ecology2006，，1： | 1 |
| 17 | Performance Analysis of Spectrum Sensing Based on Distributed Satellite Clusters under Perturbation显示文摘In this paper,we investigate the spectrum sensing performance of a distributed satellite clusters(DSC)under perturbation,aiming to enhance the sensing ability of weak signals in the coexistence of strong and weak signals.Specifically,we propose a cooperative beamforming(BF)algorithm though random antenna array theory to fit the location characteristic of DSC and derive the average far-field beam pattern under perturbation.Then,a constrained optimization problem with maximizing the signal to interference plus noise ratio(SINR)is modeled to obtain the BF weight vectors,and an approximate expression of SINR is presented in the presence of the mismatch of signal steering vector.Finally,we derive the closedform expression of the detection probability for the considered DSC over Shadowed-Rician fading channels.Simulation results are provided to validate our theoretical analysis and to characterize the impact of various parameters on the system performance. | Yunfeng Wang Xiaojin Ding Tao Hong Gengxin Zhang | 2022 | China Communications2022，19，7： | 1 |
| 18 | PEI-grafted magnetic porous powder for highly effective adsorption of heavy metal ions显示文摘 | Ya Pang Guangming Zeng Lin Tang Yi Zhang Yuanyuan Liu Xiaoxia Lei Zhen Li Jiachao Zhang Gengxin Xie | 2011 | Desalination2011，，： | 1 |
| 19 | The eddy pair off eastern Vietnam: Interannual variability and impact on thermoha- line structure显示文摘 | Chen Gengxin Hou Yijun Zhang Qilong | 2010 | Continental Shelf Research2010，30，： | 1 |
| 20 | A hierarchical autonomous system based space information network architecture and topology control显示文摘SIN(Space Information Network)has recently emerged as a promising approach to solving the collaboration difficulty among current space programs.However,because of the SIN’s large scale,high component complexity,and dynamic characteristics,designing a proper SIN architecture is challenging.Firstly,we propose a novel SIN architecture,which is composed of GEO(Geostationary Earth Orbit)satellites as backbone network nodes,LEO(Low Earth Orbit)or other types of satellites as enhanced coverage nodes,and high-altitude platforms to meet the service requirements of emergency or hot-spot applications.Unlike most existing studies,the proposed architecture is AS(Autonomous-System)based.We decouple the complex SIN into simpler sub-networks using a hierarchical AS model.Then,we propose a topology control algorithm to minimize the time delay among sub-AS networks.We prove that the proposed algorithm achieves logical k-connectivity provided that the original physical topology has k-connectivity.Simulation results validate the theoretic analysis and effectiveness of the algorithm. | ZHANG Wei ZHANG Gengxin XIE Zhidong BIAN Dongming LI Yongqiang | 2016 | Journal of Communications and Information Networks2016，1，3： | 1 |
您所在的机构暂未开通此部分的功能，请联系管理员