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Progress on research and mitigation of wind-blown sand risk in Dunhuang Singing Sand Mountain and Crescent Spring Scenic area,China

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寒旱区科学:英文版 2023年第3期15卷 113-121页

作者： BenLi Liu KeCun Zhang JianJun Qu HaiJiang Li QingHe Niu ZhiShan An yingjun pang LiHai Tan GenSheng Yang Laboratory of Ecological Safety and Sustainable Development in Arid Lands/Research Station of Gobi Desert Ecology and Environment in Dunhuang Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) GuangzhouGuangdong 51145China Administrative Office of the Dunhuang Singing Sand Mountain and Crescent Spring National Scenic Spot DunhuangGansu 736200China Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China

The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark.This scenic area underwent a 30-year transformation,i.e.,from a severe sand risk with spring water threatened by sand burial due to dune deformation,to restoration of the original sand flow field and mitigation of the sand burial problem.The current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring,observation of wind and sand flow movement,and then restoring the harmonic vibration of the sand particles(singing sand)that were previously silenced.The existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods,guiding the implementation of mitigating measures with significant ameliorative effects.Contrast to common sand control practices that aim to reduce wind speed and stop blown sands,our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding dunes.These mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport activity.Such research and mitigation efforts ensure the scientific protection and restoration of the special desert landform,and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites.

关键词： Singing Sand Mountain Crescent Spring Wind-blown sand problem Wind flow field Star dune

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Spatiotemporal changes in terrestrial water storage in the Beijing-Tianjin Sandstorm Source Region from GRACE satellites

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International Soil and Water Conservation Research 2020年第3期8卷 295-307页

作者： yingjun pang Bo Wu Yanping Cao Xiaohong Jia Institute of Desertification Studies Chinese Academy of ForestryBeijing100091China Key Laboratory of Desert Ecosystem and Global Change State Administration of Forestry and GrasslandBeijing100091China The College of Environment and Planning of Henan University Kaifeng475004HenanChina

The Sandstorm Source Control Project in and around the Beijing-Tianjin region was one of the most important ecological projects in China.Terrestrial water storage(TWS)has important impacts on the ecological construction,agriculture,industry,and resident's lives.Based on the Gravity Recovery and Climate Experiment(GRACE)data,meteorological and Moderate Resolution Imaging Spectroradiometer(MODIS)data,etc.,this paper analyzed spatiotemporal characteristics of TWS,groundwater storage,and precipitation,and explored the influencing factors of regional TWS combined with land use and land cover(LULC),social and economic data.The most important results were as follows:(1)From 2003 to 2016,TWS in the Beijing-Tianjin Sandstorm Source Region showed a decreasing trend with a rate of 3.14 mm yr-1.(2)The TWS decline was caused mainly by groundwater overexploitation,but not pre-cipitation variation.(3)Spatiotemporal variations of TWS were related to LULC.The area with the most serious decrease of TWS was mainly located in the southwestern part of the region,where farmland percentage and population density were greater.(4)Reducing the percent of farmland and tree planting,and adding the shrub and grass planting,could be a viable choice for the Beijing-Tianjin Sandstorm Source Control Project.These results provide a scientific basis for regional water resource and ecological management.

关键词： Terrestrial water storage Beijing-Tianjin Sandstorm Source Region Groundwater LULC

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Quantitative analysis on the dynamic characteristics of megadunes around the Crescent Moon Spring, China

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Journal of Arid Land 2014年第3期6卷 255-263页

作者： yingjun pang JianJun QU KeCun ZHANG ZhiShan AN QingHe NIU Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Dunhuang Gobi and Desert Research Station Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Gansu Center for Sand Hazard Reduction Engineering and Technology

The Crescent Moon Spring is a precious natural heritage. However, the dynamic characteristics of megadunes around the Crescent Moon Spring are not well known. This paper quantitatively studied the character- istics and changes of megadunes around the Crescent Moon Spring by interpreting aerial photographs taken in 1985 and 2004 and analysing the dune crestlines and the wind data collected from 2011 to 2012. Results revealed that pyramid dunes were formed by a complex wind regime. The Crescent Moon Spring was not buried by shifting sands because of the stable wind regime and relative stability of pyramid dunes. The crestlines of the dunes around the spring moved northward between 1985 and 2004. The south-facing slip faces were also exposed to wind ero- sion, whereas the other faces were under deposition, thus indicating that the southerly wind was relatively en- hanced. Limiting the scale of tall windbreaks and architectures in the Dunhuang oasis at the north of the spring was necessary to maintain the dynamic equilibrium of the wind regime and sand transport.

关键词： Dunhuang city Crescent Moon Spring pyramid dunes dynamic characteristics erosion and deposition

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Morphology and formation mechanism of sand shadow dunes on the Qinghai-Tibet Plateau

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Journal of Arid Land 2015年第1期7卷 10-26页

作者： JianHua XIAO JianJun QU ZhengYi YAO yingjun pang KeCun ZHANG Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences Dunhuang Gobi and Desert Ecology and Environment Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Gansu Center for Sand Hazard Reduction Engineering and Technology

The formation and development of dunes depend on wind-blown sand movement which is affected by the characteristics of sand material, topography, wind regimes and other factors. In this paper, we investigated two sand shadow dune groups in Shigatse and Za＇gya Zangbo of Tibet and an individual dune in Da Qaidam of Qinghai, and analyzed their topographies and morphologies, and the physical characteristics of the sand, wind regime and sand transport. Formed under harsh conditions behind hills, these mature sand shadow dunes are hundreds of meters long, have significant ridges and crescent dunes downwind, and have a hill pass on one or both sides. Wind tunnel experiments revealed that the hill gap and wind velocity are important factors in the formation of these dunes Sand shadow dunes formed only when the gap spacing is two-thirds of the hill height. When wind velocities are 20 m/s, the sand body is divided into two parts. The hill pass allows the transport of sand by wind, creating a ＂nar- row-pipe effect＂, which causes the transported material to gradually accumulate in the center of the shadow zone. We observed that the following are needed for sand shadow dunes to form：（1） strong winds, sufficient sand, suitable obstacles and a dry climate; （2） one or both sides of the obstacle forming the shadow zone must have a hill pass; and （3） the windward side of the obstacle must have a wide, flat area, providing adequate spacing for wind flow and transport of material and the leeward side must have a sufficiently broad, flat area to allow the release of the transported material. Research results on these newly discovered dunes on the Qinghai-Tibet Plateau could contribute to the understanding of dune geomorphology.

关键词： sand shadow dune morphology aeolian landform wind tunnel Qinghai-Tibet Plateau

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Wind-proof and sand-fixing effects of Artemisia ordosica with different coverages in the Mu Us Sandy Land,northern China

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Journal of Arid Land 2022年第8期14卷 877-893页

作者： pang yingjun WU Bo JIA Xiaohong XIE Shengbo Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China Institute of Ecological Conservation and Restoration Chinese Academy of ForestryBeijing 100091China Key Laboratory of Desert Ecosystem and Global Change National Forestry and Grassland AdministrationBeijing 100091China Kumtag Desert Ecosystem Research Station National Forestry and Grassland AdministrationDunhuang 736200China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Wind erosion is a key global environmental problem and has many adverse effects.The Mu Us Sandy Land of northern China is characterized by an arid climate,where vegetation patches and bare sand patches are usually distributed mosaically,and aeolian activities occur frequently.Vegetation plays a significant role in controlling wind erosion.Artemisia ordosica is the most dominant native plant species in the Mu Us Sandy Land.It is urgent to study the wind-proof and sand-fixing effects of Artemisia ordosica in the Mu Us Sandy Land.This study analyzed the wind-proof and sand-fixing effects of Artemisia ordosica based on the field data of wind regimes,aeolian sediment transport,and surface change of Artemisia ordosica plots with four coverages(denoted as site A,site B,site C,and site D)in the Mu Us Sandy Land during the period from 1 June 2018 to 29 June 2019.The coverages of Artemisia ordosica at site A,site B,site C,and site D were 2%,16%,29%,and 69%,respectively.The annual average wind speeds at 2.0 m height above the ground for site A,site B,site C,and site D were 3.47,2.77,2.21,and 1.97 m/s,respectively.The annual drift potentials were 193.80,69.72,15.05,and 6.73 VU at site A,site B,site C,and site D,respectively.The total horizontal aeolian sediment fluxes during the period from 2-3 June 2018 to 6 June 2019 at site A,site B,site C,and site D were 4633.61,896.80,10.54,and 6.14 kg/m,respectively.Site A had the largest surface changes,and the surface changes at site B were significantly weaker than those at site A,whereas the surface changes at site C and site D were minimal.The results indicated that Artemisia ordosica significantly reduced the wind speed,drift potential,aeolian sediment transport,and surface changes.The higher the coverage of Artemisia ordosica is,the more obvious the effects of wind-proof and sand-fixing.Wind erosion would be effectively controlled in the Mu Us Sandy Land if the coverage of Artemisia ordosica is greater than 29%.These results provide a scientific basis for evaluating the ecosyste

关键词： Artemisia ordosica wind-proof sand-fixing wind erosion aeolian sediment flux Mu Us Sandy Land

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Experimental definition and its significance on the minimum safe distance of blown sand between the proposed Qinghai-Tibet Expressway and the existing Qinghai-Tibet Railway

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Science China(Technological Sciences) 2020年第12期63卷 2664-2676页

作者： XIE ShengBo QU JianJun HAN QingJie pang yingjun Key Laboratory of Desert and Desertification Dunhuang Gobi and Desert Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China

The Qinghai-Tibet Expressway is a major strategic project planned by China that will be built along the Qinghai-Tibet Engineering Corridor. At present,important traffic line projects,such as the Qinghai-Tibet Railway,have been built within this narrow corridor,particularly at the blown sand sections. How to ensure that the wind speed and its flow field between the new expressway and existing railway subgrades are not affected by each other is a priority to prevent breaking the dynamic balance of the blown sand movement of the existing subgrade,thereby avoiding aggravating or inducing new blown sand hazards and ensure the safe operation of the existing Qinghai-Tibet Railway. Therefore,defining the minimum distance of the wind speed and its flow field,which are not affected by each other,between the subgrades become a scientific problem that should be solved immediately to implement the construction of the Qinghai-Tibet Expressway. For this purpose,the minimum safe distance between the subgrades of the Qinghai-Tibet Expressway and Qinghai-Tibet Railway was investigated from the perspective of blown sand by making subgrade models for conducting wind tunnel experiments and combining the observation data of the local field. Results indicated that the minimum safe distance between the two subgrades is 45–50 times the subgrade height when the Qinghai-Tibet Expressway is located at the downwind direction of the Qinghai-Tibet Railway,and 50 times the subgrade height when the former is located at the upwind direction of the latter. These results have guiding significance for the route selection,survey,and design of the Qinghai-Tibet Expressway at the blown sand sections and for the traffic line projects in other similar sandy regions.

关键词： Qinghai-Tibet Expressway Qinghai-Tibet Railway wind speed wind flow field safety distance

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Morphological characteristics and dynamic changes of seif dunes in the eastern margin of the Kumtagh Desert,China

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Journal of Arid Land 2020年第5期12卷 887-902页

作者： pang yingjun WU Bo LI Yonghua XIE Shengbo Institute of Desertification Studies Chinese Academy of ForestryBeijing 100091China Key Laboratory of Desert Ecosystem and Global Change State Administration of Forestry and GrasslandBeijing 100091China Kumtagh Desert Ecosystem Research Station State Administration of Forestry and GrasslandDunhuang 736200China Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The seif dune field over the gravel desert surface in the eastern margin of the Kumtagh Desert is a valuable experimental site for the observation of dune formation and dynamics.We used high-resolution remote sensing and station observation approaches,combined with wind and grain size data,to study the characteristics of the aeolian environment and the morphologies of and dynamic changes in seif dunes.We observed the ratio of the resultant drift potential(RDP)to the drift potential(DP),which was 0.37,associated with an obtuse bimodal wind regime.The drift potentials in the west-northwest(WNW)and east-northeast(ENE)directions were dominant,and the angle between the two primary DP directions was 135.00°.The dune orientations ranged from 168.75°-213.75°,which were parallel to the resultant drift direction(186.15°).The dune lengths ranged from 51.68 to 1932.1 m with a mean value of 344.91 m.The spacings of the dunes ranged from 32.34 to 319.77 m with a mean value of 93.39 m.The mean grain size of the sediments became finer,and the sorting became better from upwind tail to downwind tip,which indicated that the sediment of the seif dunes in the study region may be transported from northward to southward.The rate of increase in the length,the mean longitudinal migration rate of the dune tail,and the mean longitudinal extension rate of the dune tip(also called elongation rate)were 4.93,4.63,and 9.55 m/a,respectively.The mean lateral migration vector of the seif dunes was approximately 0.11 m/a towards the west(-0.11 m/a),while the mean amplitude of lateral migration was 0.53 m/a,ignoring the direction of lateral migration.We found that the seif dune field formed first beside seasonal rivers,which can provide sediment,and then expanded downwind.

关键词： seif dune Kumtagh Desert elongation migration drift potential

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Current assessment and management of measurable residual disease in patients with acute lymphoblastic leukemia in the setting of CAR-T-cell therapy

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Chinese Medical Journal 2024年第2期137卷 140-151页

作者： Minghao Lin Xiaosu Zhao yingjun Chang Xiangyu Zhao Peking University People’s Hospital Peking University Institute of HematologyNational Clinical Research Center for Hematologic DiseaseBeijing Key Laboratory of Hematopoietic Stem Cell TransplantationBeijing 100044China

Chimeric antigen receptor(CAR)-modified T-cell therapy has achieved remarkable success in the treatment of acute lymphoblastic leukemia(ALL).Measurable/minimal residual disease(MRD)monitoring plays a significant role in the prognostication and management of patients undergoing CAR-T-cell therapy.Common MRD detection methods include flow cytometry(FCM),polymerase chain reaction(PCR),and next-generation sequencing(NGS),and each method has advantages and limitations.It has been well documented that MRD positivity predicts a poor prognosis and even disease relapse.Thus,how to perform prognostic evaluations,stratify risk based on MRD status,and apply MRD monitoring to guide individual therapeutic decisions have important implications in clinical practice.This review assesses the common and novel MRD assessment methods.In addition,we emphasize the critical role of MRD as a prognostic biomarker and summarize the latest studies regarding MRD-directed combination therapy with CAR-T-cell therapy and allogeneic hematopoietic stem cell transplantation(allo-HSCT),as well as other therapeutic strategies to improve treatment effect.Furthermore,this review discusses current challenges and strategies for MRD detection in the setting of disease relapse after targeted therapy.

关键词： Measurable/minimal residual disease Acute lymphoblastic leukemia Chimeric antigen receptor-modified T-cell therapy Allogeneic hematopoietic stem cell transplantation Relapse

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Enhancing source domain availability through data and feature transfer learning for building power load forecasting

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Building Simulation 2024年第4期17卷 625-638页

作者： Fanyue Qian yingjun Ruan Huiming Lu Hua Meng Tingting Xu College of Mechanical and Energy Engineering Tongji UniversityShanghai200092China United Automotive Electronic Systems Co. LtdShanghai201206China

During the initial phases of operation following the construction or renovation of existing buildings,the availability of historical power usage data is limited,which leads to lower accuracy in load forecasting and hinders normal usage.Fortunately,by transferring load data from similar buildings,it is possible to enhance forecasting accuracy.However,indiscriminately expanding all source domain data to the target domain is highly likely to result in negative transfer learning.This study explores the feasibility of utilizing similar buildings(source domains)in transfer learning by implementing and comparing two distinct forms of multi-source transfer learning.Firstly,this study focuses on the Higashita area in Kitakyushu City,Japan,as the research object.Four buildings that exhibit the highest similarity to the target buildings within this area were selected for analysis.Next,the two-stage TrAdaBoost.R^(2) algorithm is used for multi-source transfer learning,and its transfer effect is analyzed.Finally,the application effects of instance-based(IBMTL)and feature-based(FBMTL)multi-source transfer learning are compared,which explained the effect of the source domain data on the forecasting accuracy in different transfer modes.The results show that combining the two-stage TrAdaBoost.R^(2) algorithm with multi-source data can reduce the CV-RMSE by 7.23%compared to a single-source domain,and the accuracy improvement is significant.At the same time,multi-source transfer learning,which is based on instance,can better supplement the integrity of the target domain data and has a higher forecasting accuracy.Overall,IBMTL tends to retain effective data associations and FBMTL shows higher forecasting stability.The findings of this study,which include the verification of real-life algorithm application and source domain availability,can serve as a theoretical reference for implementing transfer learning in load forecasting.

关键词： building power load multi-source transfer learning two-stage TrAdaBoost.R2 source domain availability

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Design and calibration of spoke piezoelectric six-dimensional force/torque sensor for space manipulator

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Chinese Journal of Aeronautics 2024年第1期37卷 218-235页

作者： yingjun LI Guicong WANG Shuai ZHANG Yuanqin ZHOU Hongyu LI Zhenguang QI School of Mechanical Engineering University of JinanJinan 250022China

The large manipulator outside the space cabin is a multi-degree of freedom actuator for space operations.In order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoelectric six-dimensional force/torque sensor with redundancy ability,high stiffness and good decoupling performance is innovatively proposed.Based on the deformation coordination relationship,the redundancy measurement mechanism is revealed.The mathematical models of the sensor with and without branch fault are established respectively.The finite element model is established to verify the feasibility of structure and redundancy measuring principle of the sensor.Depending on the theoretical analysis and simulation analysis,the prototype of the sensor is developed.Static and dynamic calibration experiments are carried out.The actual output voltage signal of the six-dimensional force/torque sensor is collected to establish the equation between the standard input applied load and the actual output voltage signal.Based on ant colony optimized BP algorithm,performance indexes of the sensor with and without branch fault are analyzed respectively.The experimental results show that the spoke piezoelectric sixdimensional force/torque sensor with the eight-point support structure has good accuracy and reliability.Meanwhile,it has strong decoupling characteristic that can effectively shield the coupling between dimensions.The nonlinear errors and maximum interference errors of decoupled data with and without branch faults are less than 1% and 2%,respectively.The natural frequency of the sixdimensional force sensor can reach 2856.45 Hz and has good dynamic characteristics.The research content lays a theoretical and experimental foundation for the design,development and application of the new six-dimensional force/torque sensors with redundancy.Meanwhile,it will significantly improve the research level in this field,and provide a strong guarantee for the smooth implementation of force feedback control of th

关键词： Decoupling algorithm Piezoelectric Redundancy Six-dimensional force/torque sensor Space manipulator

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