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Spatial heterogeneity of the driving forces of cropland change in china

Science china Earth sciences 2005年第12期48卷 2231-2240页

作者： liu xuhua1,2. wang jinfeng1,{2.,{3.,2.3.1. institute of geographic sciences and natural resources research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of sciences, Beijing 10003., china 3. College of Arts and sciences of Beijing Union University, Beijing 100083. china 4. School of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL3.849, USA 1. institute of geographic {2. and {3. resources research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. School of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in{2.. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of{2., natural condition changes and geographical background were the main constraints and drivers, while in Eastern{2., social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in{2. recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

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Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & liu Changming1, 2.1. School of Environmental sciences, Beijing Normal University, Beijing 100875,{2. 2. institute of {3. Science and natural resources research, Beijing 100101,{2. Beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982.1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982.to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3. the evapotranspiration of 3.00-3.00 km3. and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

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The study on Sanmenxia annual flow forecasting in the Yellow River with mix regression model

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Science china(Technological sciences) 2004年第z1期47卷 118-126页

作者： JIANG Xiaohui1, liu Changming1,2. wang Yu3.& wang Hongrui1 1. Beijing Normal University, Beijing 100875, china 2. {3. of geographic Science and natural resources, Chinese Academy of sciences, Beijing 100101, china 3. Reconnaissance, Planning, Design and {13. {3., YRCC, Zhengzhou 450003. china Beijing Normal Univ Beijing 100875 Peoples R China Chinese Acad Sci Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China YRCC Reconnaissance Planning Design & Res Inst Zhengzhou 450003 Peoples R China

This paper established mix regression model for simulating annual flow, in which annual runoff is auto-regression factor, precipitation, air temperature and water consumption are regression factors; we adopted 9 hypothesis climate change schemes to forecast the change of annual flow of Sanmenxia Station. The results show : (1) When temperature is steady, the average annual runoff will increase by 8.3. if precipitation increases by 10%; when precipitation decreases by 10%, the average annual runoff will decrease by 8.2.; when precipitation is steady, the average annual runoff will decrease by 2.4% if temperature increases 1℃; if temperature decreases 1℃, runoff will increase by 1.2.. The mix regression model can well simulate annual runoff. (2. As to 9 different temperature and precipitation scenarios, scenario 9 is the most adverse to the runoff of Sanmenxia Station of Yellow River; i.e. temperature increases 1℃ and precipitation decreases by 10%. Under this condition, the simulated average annual runoff decreases by 10.8%. On the contrary, scenario 1 is the best to the enhancement of runoff; i.e. when temperature decreases 1 ℃ precipitation will increase by 10%, which will make the annual runoff of Sanmenxia increase by 10.6%.

关键词： forecast annual flow, mix regression model, Sanmenxia Station

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Point Cloud Classification Using Content-Based Transformer via Clustering in Feature Space

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 231-239页

作者： Yahui liu bin Tian Yisheng Lv Lingxi Li Fei-Yue {2. the State Key Laboratory for Management and Control of Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100190 IEEE the Transportation and Autonomous Systems institute(TASI)and the Department of Electrical and Computer Engineering Purdue School of Engineering and TechnologyIndiana University-Purdue University Indianapolis(IUPUI)Indianapolis 46202 USA

Recently, there have been some attempts of Transformer in 3. point cloud classification. In order to reduce computations, most existing methods focus on local spatial attention,but ignore their content and fail to establish relationships between distant but relevant points. To overcome the limitation of local spatial attention, we propose a point content-based Transformer architecture, called PointConT for short. It exploits the locality of points in the feature space(content-based), which clusters the sampled points with similar features into the same class and computes the self-attention within each class, thus enabling an effective trade-off between capturing long-range dependencies and computational complexity. We further introduce an inception feature aggregator for point cloud classification, which uses parallel structures to aggregate high-frequency and low-frequency information in each branch separately. Extensive experiments show that our PointConT model achieves a remarkable performance on point cloud shape classification. Especially, our method exhibits 90.3. Top-1 accuracy on the hardest setting of ScanObjectN N. Source code of this paper is available at https://***/yahuiliu99/PointC onT.

关键词： Content-based Transformer deep learning feature aggregator local attention point cloud classification

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COVID-19 vaccine updates for people under different conditions

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Science china Life sciences 2024年第11期67卷 2323-2343页

作者： Yijiao Huang Weiyang wang Yan liu Zai wang {3. Cao National Center for Respiratory Medicine State Key Laboratory of Respiratory Health and Multimorbidity National Clinical research Center for Respiratory Diseases institute of Respiratory Medicine Chinese Academy of Medical Sciences Department of Pulmonary and Critical Care Medicine Center of Respiratory Medicine China-Japan Friendship Hospital School of Basic Medical sciences Tsinghua Medicine Tsinghua University Tsinghua University-Peking University Joint Centre for Life sciences Tsinghua University Peking Union Medical College Chinese Academy of Medical Sciences Department of Infectious Disease The Affiliated Yantai Yuhuangding Hospital of Qingdao University institute of Clinical Medical sciences China-Japan Friendship Hospital Changping Laboratory Department of Respiratory Medicine Capital Medical University New Cornerstone Science Laboratory China-Japan Friendship Hospital

SARS-Co V-2.has caused global waves of infection since December 2.19 and continues to persist today. The emergence of SARS-Co V-2.ariants with strong immune evasion capabilities has compromised the effectiveness of existing vaccines against breakthrough ***, it is important to determine the best utilization strategies for different demographic groups given the variety of vaccine options available. In this review, we will discuss the protective efficacy of vaccines during different stages of the epidemic and emphasize the importance of timely updates to target prevalent variants, which can significantly improve immune protection. While it is recognized that vaccine effectiveness may be lower in certain populations such as the elderly, individuals with chronic comorbidities(e.g., diabetes with poor blood glucose control, those on maintenance dialysis), or those who are immunocompromised compared to the general population,administering multiple doses can result in a strong protective immune response that outweighs potential risks. However, caution should be exercised when considering vaccines that might trigger an intense immune response in populations prone to inflammatory flare or other complications. In conclusion, individuals with special conditions require enhanced and more effective immunization strategies to prevent infection or reinfection, as well as to avoid the potential development of long COVID.

关键词： SARS-CoV-2 vaccine variants of concern elderly immunocompromised

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Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai

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Science china Earth sciences 2005年第7期48卷 939-949页

作者： SHAO Xuemei1, HUANG Lei1, liu Hongbin2. LIANG Eryuan1, FANG Xiuqi3.& {2. Lili1 1. institute of geographic {3. and natural resources research, Chinese Academy of {3., Beijing 100101, china 2. National Climate Center, Beijing 100081, china 3. Beijing Normal University, Beijing 100875, china institute of geographic {2. Natural Resources Research Chinese Academy of Sciences Beijing 100101 China National Climate Center Beijing 100081 China Beijing Normal University Beijing 100875 China

Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD152.—163. and 193.—2.01, whereas dry intervals in 142.—1519 and 163.—1741. In ad- dition, the magnitude in precipitation variation was lower before 143. with about 15 mm, but it increased to 3. mm during the period of 143. to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 2.st century.

关键词： northeastern part of the Qaidam Basin tree-ring width series of Qilian juniper precipitation reconstruction in 1000 years.

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Indoor imitation experimental study on driving factors of rainfall-runoff process

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Science china Earth sciences 2005年第3期48卷 417-428页

作者： ZHANG Shifeng1, liu Changming 1, XIA Jun1, TAN Ge 1, LI Lin1, liu Caitang1, ZHOU Changqing 1 & GUO Lei2.1. {2. of geographic sciences and {3. resources research, Chinese Academy of sciences, Beijing 100101, china 2. College of Water resources and Hydropower Engineering, Wuhan University, Wuhan 43.072. china 1. institute of geographic {2. and {3. resources research Chinese Academy of Sciences 100101 Beijing China 2. College of Water resources and Hydropower Engineering Wuhan University 430072 Wuhan China

The driving actions of rainfall-runoff process can be attributed to two aspects. The first is the influence of precipitation process, and the second is that of the ground pad. The re- search results of 179 indoor experiments conducted to imitate rainfall-runoff process indicate that both precipitation duration and intensity play important roles in affecting confluence lag time, which is obviously inconsistent with the traditional hypotheses. The nonlinear relationship is of great significance to the confluence curve especially when the precipitation duration is less than the total confluence time or the precipitation intensity is small. Therefore it can be concluded that the unit hydrograph (UH) can be applied to rainfall-runoff process imitation in the humid areas in the south china region. However, the UH application should be strictly modified in accordance with precipitation conditions in the arid and semiarid region of north china where the precipitation duration is short and the intensity is unstable. It will be hard to get ideal imitation results if the UH is applied blindly without considering specific conditions in the north china region. This also explains the unsatisfactory imitation results caused by using various hydrological models in the north china region. When the precipitation duration is short, and the watershed has not reached total watershed concentration, the characteristics of confluence change greatly, which reflects the actual situation in the north china region. Therefore necessary nonlinear corrections should be made when UH is applied. If the duration is longer than the total confluence time and the balance between pondage and discharge is stricken, the imitation research results will be applicable to both rainfall-runoff relation with longer duration in the south china region and the basic theoreti- cal research on runoff generation and concentration. On conditions of adequate rainfall, peak discharge is in linear relationship with inten

关键词： rainfall-runoff, driving factors, indoor imitation, experiment.

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Aggregation-induced T_(1)/T_(2. contrast enhancement for magnetic resonance imaging-guided intraoperative surgery

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Science china Chemistry 2024年第6期67卷 2046-2055页

作者： Wenbo Sun bin Yu Dianshuai Huang Chunhuan Jiang Wei wang Jianhua {2. Zonghua wang Lehui Lu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China College of Chemistry and Chemical Engineering Shandong Sino-Japanese Center for Collaborative Research of Carbon NanomaterialsQingdao Application Technology Innovation Center of Photoelectric Biosensing for Clinical Diagnosis and TreatmentQingdao UniversityQingdao266071China Department of Radiology Second Hospital of Jilin UniversityChangchun130041China

Magnetic resonance imaging(MRI)plays an important role in precision medicine that is hampered by the lack of contrast agents with high efficiency and the ability to translate diagnostic accuracy into therapeutic ***,we demonstrate a DNA-based MRI probe that overcomes previous single-mode enhancement and provides a mechanism of action for aggregationinduced dual-modal MRI signal enhancement.A facile method is developed to produce aggregated T_(1)/T_(2.dual-modal NaGdF_(4):Dy@PDA-DNA(PDA=polydopamine)MRI *** aggregated,this probe can further amplify MRI signal intensity and exhibit improved geometrical and positional stability in *** performance of the NaGdF_(4):Dy@PDA-DNA MRI probe toward MRI-guided preoperative planning and visualization-guided surgery is verified using an orthotopic tumor-bearing mouse *** result shows that the rapid metabolism of the degraded probe leads to the mitigation of long-term toxic ***,the developed high-performance MRI probe is of great significance for enhancing MRI diagnostic accuracy into precision medical therapeutic interventions.

关键词： MRI probe DNA aggregation-induced T_(1)/T_(2.contrast enhancement precision medicine degradable probe

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Orientation controlled photogenerated carriers on selfsupporting CdS/Ni_(3.S_(2. paper toward photocatalytic hydrogen evolution and biomass upgrading

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Rare Metals 2024年第5期43卷 2015-2025页

作者： Xiao-Yan liu Qing Cao Gui-Xiang Li Hui liu Li-Li Zeng Li-Li Zhao {2. Chang Xi-Wen {3. Hong liu Wei-Jia Zhou institute for Advanced Interdisciplinary research School of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China institute of Chemical sciences and Engineering Ecole Polytechnique Federale de Lausanne1015LausanneSwitzerland KAUST Catalysis Center King Abdullah University of Science and TechnologyThuwal 23955-6900Kingdom of Saudi Arabia School of Environment and Energy South China University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China State Key Laboratory of Crystal Materials Shandong UniversityJinan250100China School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710054China

The appropriate regulation of band structure is an effective strategy in constructing efficient photocatalytic *** photocatalytic system mainly employs powder photocatalysts,which makes their recovery reliant on expensive separation processes and severely limits their industrial ***,we constructed a novel CdS/Ni_(3.S_(2.heterostructure using free-standing and flexible nickel fiber paper as the *** regulated energy band structure achieves effective electron–hole *** as-synthesized flexible photocatalyst exhibits considerable photocatalytic activity toward the H_(2.evolution reaction under visible-light irradiation,with an H_(2.production rate of5.63.mol·cm^(-2.·h^(-1)(14.1 mmol·g^(-1)cat·h^(-1)according to the catalyst loading content).Additionally,the otherwisewasted excited holes simultaneously drive organic transformations to yield value-added organic products,thus markedly improving the photocatalytic H_(2.evolution *** a photocatalytic system is scaled up further,where a self-supported 2. cm×2. cm sample achieves a champion H_(2.production rate of 60-80μmol·h^(-1)under practical sun *** newly developed self-supported photocatalyst produces opportunities for practical solar H2.roduction with biomass upgrading.

关键词： Self-supporting photocatalyst CdS/Ni_(3.S_(2. heterojunction Hydrogen evolution Biomass upgrading Large-scaleapplication

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Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. liu Chuang1, 3.1. institute of {2. sciences and {3. resources research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate University of Chinese Academy of sciences, Beijing 100049, china 3. College of resources Science and Technology, Beijing Normal University, Beijing 100875, china institute of geographic {2. and {3. resources research Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of sciences Beijing China College of resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993.the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth {2. satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993.to 2.08. There were 12.63..54 hm2.cropland de-creased between 1993.and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world {2. {3.es.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection

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