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Applied Mathematics and Mechanics(English Edition) 1990年第11期11卷 1043-1054页

作者： Fu Bao-lian li nong Yanshan University Qinhuangdao Luoyang Technology Institute.Luoyang

In this paper, applying the method of reciprocal theorem, we give the distributions of the amplitude of bending moments along clamped edges and the amplitude of deflections along free edges of rectangular plates with ... 详细信息

关键词： the method of reciprocal theorem force vibration the amplitude of bending moment the amplitude of deflection elastic thin plate

Ridge-furrow rainwater harvesting with supplemental irrigation to improve seed yield and water use efficiency of winter oilseed rape(Brassica napus L.)

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Journal of Integrative Agriculture 2017年第5期16卷 1162-1172页

作者： GU Xiao-bo li Yuan-nong DU Ya-dan YIN Min-hua College of Water Resources and Architectural Engineering Northwest A&F University/Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid AreaMinistry of EducationYangling 712100P.R.China

Ridge-furrow rainwater harvesting （RFRH） planting pattern can lessen the effect of water deficits throughout all crop growth stages, but water shortage would remain unavoidable during some stages of crop growth in arid and semiarid areas. Supplemental irrigation would still be needed to achieve a higher production. Field experiments were conducted for two growing seasons （2012-2013 and 2013-2014）to determine an appropriate amount of supplemental irrigation to be applied to winter oilseed rape at the stem-elongation stage with RFRH planting pattern. Four treatments, including supplemental irrigation amount of 0 （I1）, 60 mm （I2） and 120 mm （I3） with RFRH planting pattern and a control （CK） irrigated with 120 mm with flat planting pattern, were set up to evaluate the effects of supplemental irrigation on aboveground dry matter （ADM）, nitrogen nutrition index （NNI）, radiation use efficiency （RUE）, water use efficiency （WUE）, and seed yield and oil content of the oilseed rape. Results showed that supplemental irrigation improved NNI, RUE, seed yield and oil content, and WUE. However, the NNI, RUE, seed yield and oil content, and WUE did not increase significantly or even showed a downward trend with excessive irrigation. Seed yield was the highest in 13 for both growing seasons. Seed yield and WUE in 13 averaged 3235 kg ha^-1 and 8.85 kg ha^-1 mm-1, respectively. The highest WUE was occurred in 12 for both growing seasons. Seed yield and WUE in 12 averaged 3089 kg ha^-1 and 9.63 kg ha^-1 mm^-1, respectively. Compared to 13, 12 used 60 mm less irrigation amount, had an 8.9% higher WUE, but only 4.5 and 0.4% lower seed yield and oil content, respectively. 12 saved water without substantially sacrificing yield or oil content, so it is recommended as an appropriate cultivation and irrigation schedule for winter oilseed rape at the stem-elongation stage.

关键词： ridge-furrow rainwater harvesting (RFRH) supplemental irrigation winter oilseed rape seed yield oil content water use efficience (WUE)

Mechanism of subsidence-buckling and instability of slopes in thick-layered rigid rock under mining

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Journal of Mountain Science 2023年第8期20卷 2370-2387页

作者： DENG Jie ZHAO Jian-jun LAI Qi-yi li Ai-nong XIE Ming-li li Qing-miao ZHAO Xiao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China POWERCHINA Chengdu Engineering Corporation limited Chengdu 610072China

The deformation and failure of mining slopes in layered rocks predominantly result from shear ***,the instability process of the Pusa rock avalanche in Guizhou,China,revealed a unique damage phenomenon:prominent breaking and toppling of rock blocks occurred in the central section of the mountain,with a lack of commonly observed shear landslide *** paper aims to investigate the underlying reasons behind this distinctive damage *** study employs various methods including geological survey,UAV aerial survey,physical simulation,and discrete element numerical *** findings indicate that the geological conditions,characterized by a hard upper layer and a soft lower layer along with underground mining activities,play a significant role in triggering the ***,the presence of a columnar structured rock mass emerges as the primary factor influencing the instability of the Pusa rock *** elucidate the mining failure mechanism of the rock mass with vertical joints,we propose a"subsidence-buckling"failure *** the subsidence and collapse of the roof rock mass in the goaf,the columnar rock mass in the upper and middle portions of the slope undergoes deflection and deformation,forming a three-hinged arch *** structural configuration converts the pressure exerted by the overlying rock mass into both vertical pressure and lateral *** the influence of external loads,the slope experiences buckling failure,ultimately leading to instability upon *** shedding light on these findings,this study contributes to a better understanding of the spatiotemporal evolution of mining slope fractures and their impact on slope stability.

关键词： Mining landslide Failure mechanism Block structure Failure characteristics Soft-hard interbedding

Validation of Global Land Surface Satellite (GLASS) Downward Shortwave Radiation Product in the Rugged Surface

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Journal of Mountain Science 2013年第5期10卷 812-823页

作者： JIN Hua-an li Ai-nong BIAN Jin-hu ZHANG Zheng-jian HUANG Cheng-quan li Meng-xue Institute of Mountain Hazards and Environment Chinese Academy of Sciences Department of Geographical Sciences University of MarylandCollege Park

The downward shortwave radiation(DSR) is an essential parameter of land surface radiation budget and many land surface models that characterize hydrological,ecological and biogeochemical *** new Global LAnd Surface Satellite(GLASS) DSR datasets have been generated recently using multiple satellite data in *** study investigates the performances of direct comparison approach,which is mostly used for validation of surface insolation retrieved from satellite data over the plain area,and indirect comparison approach,which needs a fine resolution map of DSR as reference,for validation of GLASS DSR product in time-steps of 1 and 3 hours over three Chinese Ecosystem Research Network sites located in the rugged *** suggest that it probably has a large uncertainty to assess GLASS DSR product using the direct comparison method between GLASS surface insolation and field measurements over complex terrain,especially at *** 3,000 m station with root mean square error of 279.04 and 229.06 W/m2in time-steps of 1 and 3 hours,*** improvement for validation of GLASS DSR product in the rugged surface is suggested by generation of a fine resolution map of surface insolation and comparison of the aggregated fine resolution map with GLASS product in the rugged *** validation experience demonstrates that the GLASS DSR algorithm is satisfactory with determination coefficient of 0.83 and root mean square error of 81.91W/m2over three Chinese Ecosystem Research Network sites,although GLASS product overestimates DSR compared to the aggregated fine resolution map of surface insolation.

关键词： Downward shortwave radiation Validation Complex terrain

Auto-registration and Orthorecification Algorithm for the Time Series HJ-1A/B CCD Images

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Journal of Mountain Science 2013年第5期10卷 754-767页

作者： BIAN Jin-hu li Ai-nong JIN Hua-an LEI Guang-bin HUANG Cheng-quan li Meng-xue Digital Mountain and Remote Sensing Application Center Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences University of Chinese Academy of Sciences Department of Geography University of Maryland2181 LeFrak HallCollege Park

How to deal with geometric distortion is an open problem when using the massive amount of satellite images at a national or global scale, especially for multi-temporal image analysis. In this paper, an algorithm is proposed to automatically rectify the geometric distortion of time-series CCD multi- spectral data of small constellation for environmental and disaster mitigation （HJ-1A/B） which was launched by China in 2008. In this algorithm, the area-based matching method was used to automatically search tie points firstly, and then the polynomial function was introduced to correct the systematic errors caused by the satellite motion along the roll, pitch and yaw direction. The improved orthorectification method was finally used to correct pixel displacement caused by off-nadir viewing of topography, which are random errors in the images and cannot be corrected by the polynomial equation. Nine scenes of level 2 HJ CCD images from one path/row were taken as the warp images to test the algorithm. The test result showed that the overall accuracy of the proposed algorithm was within 2 pixels （the average residuals were 37.8 m, and standard deviations were 19.8 m）. The accuracies of 45.96% validation points （VPs） were within 1 pixel and 90.33% VPs were within 2 pixels. The discussion showed that three main factors including the distortion patterns of HJ CCD images, pereent of cloud cover and the varying altitude of the satellite orbit may affect the search of tie points and the accuracy of results. Although the influence of varying altitude of the satellite orbits is less than the other factors, it is noted that detailed satellite altitude information should be given in the future to get a more precise result. The proposed algorithm should be an efficient tool for the geo-correction of HJ CCD multi-spectral images.

关键词： HJ time series images Auto-geocorrection Topographic correction Widecoverage CCD cameras

Parameter Extension and the Quasi-Rational Solution of a Lattice Boussinesq Equation

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Chinese Physics Letters 2013年第4期30卷 1-4页

作者： nong li-Juan ZHANG Da-Jun SHI Ying ZHANG Wen-Ying Department of Mathematics Shanghai UniversityShanghai 200444

For a lattice Boussinesq equation,we introduce a simple-parameter invertible transformation by which the equation is transformed into an extended *** new equation admits solitons and nonzero quasi-rational solutions,b... 详细信息

关键词： equation. Boussinesq equation

A Secure communication method for a high-power information signal based on chaotic masking

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Chinese Physics B 2002年第11期11卷 1124-1127页

作者： li Jian-Fen(李建芬) li nong(李农) The Engineering Institute of the Air Force Engineering University Xi'an 710038 China

In this paper, we present a secure communication method for a high-power information signal based on chaoticmasking. In the transmitter, an adaptive controller is adopted to pick up the change of the information signal, andto inject the controller's error into the transmitting system. At the same time, the information is directly added tothe chaotic signal in transmission to drive the receiving system. In the receiver, another adaptive controller is usedto maintain chaotic synchronization of the transmitting and receiving systems and to recover the information *** the synchronization error is independent from the information signal, the power of the information signal can beequivalent to that of the chaotic signal, and the frequency of the information signal can be set within the range of theprincipal frequencies of the chaotic signal. The results of theoretical analysis and numerical simulation show that thepresented method not only enhances the degree of security of low-dimensional chaotic systems but also significantlyimproves the signal-to-noise ratio at the receiving end.

关键词： chaotic masking secure communications adaptive controllers Chua's circuits

Negation of the negation on beta-blockers in patients with cardiovascular diseases and noncardiac surgery

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医学争鸣 2013年第4期4卷 36-41页

作者： SUN Jian-Zhong DING Qian YAO li-nong Department of Anesthesiology Thomas Jefferson University Department of Anesthesiology Tangdu Hospital Fourth Military Medical University

The best protocol of perioperative beta-blockers remains *** studies have demonstrated that tight heart rate control by beta-blockers reduced perioperative myocardial ischemia and improved clinical ***,the recent studies have failed to provide evidence to support perioperative beta blockers,with potential increased mortality as showed in the POISE *** this paper,perioperative use of beta-blockers will be discussed,especially about the evolution of their perioperative therapeutic application and current status.

关键词：摘要编辑部编辑工作读者

Treatment response between Asian and non-Asian patients with type 2diabetes:is there any similarity or difference?

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Chinese Medical Journal 2019年第1期132卷 1-3页

作者： Xiao-ling Cai li-nong Ji Department of Endocrinology and Metabolism Peking University People's HospitalBeijing 100044China

Introduction According to the latest edition of Diabetes Atlas,the prevalence of diabetes is increasing globally,but the situation is particularly alarming in Asia and in China.[1,2,3] It was estimated that,for the same body mass index (BMI),Asian population had a higher prevalence of diabetes than the non-Asian counterparts,[4] because of the lower BMIs reported in Asian diabetes population.

关键词： Type 2 diabetes Asia body mass index (BMI)

Landscape Pattern Evolution Processes of Alpine Wetlands and Their Driving Factors in the Zoige Plateau of China

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Journal of Mountain Science 2013年第1期10卷 54-67页

作者： BAI Jun-hong LU Qiong-qiong WANG Jun-jing ZHAO Qing-qing OUYANG Hua DENG Wei li Ai-nong State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Zoige Plateau wetlands are located in the northeastern corner of the Qinghai-Tibet *** landscape pattern evolution processes in the Zoige Plateau and their driving factors were identified by analyzing the dynamic changes in landscape modification and conversion and their dynamic rates of alpine wetlands over the past four *** results showed that the landscape conversion between wetlands and non-wetlands mainly occurred during the period from 1966 to *** marsh wetland area converted from lake and river wetlands was larger because of swamping compared to other wetland ***,the larger area of marsh wetlands was also converted to lake wetlands more than other types of *** modification processes mainly occurred among natural wetland landscapes in the first three *** conversions were observed between wetland and nonwetland landscapes(i.e.,forestland,grassland,and other landscapes) in the Zoige *** natural wetland landscapes such as river,lake and marsh wetlands showed a net loss over the past four decades,whereas artificial wetland landscapes(i.e.,paddy field and reservoir and pond wetlands) showed a net *** annual dynamic rate of the whole wetland landscape was 0.72%,in which the annual dynamic rate of river wetlands was the highest,followed by lake wetlands,while marsh wetlands had the lowest dynamic *** integrated landscape dynamic rate showed a decreasing trend in the first three *** changes in wetland landscape patterns were comprehensively controlled by natural factors and human activities,especially human activities play an important role in changing wetland landscape patterns.

关键词： Zoige Plateau Alpine wetland Landscape pattern Modification Conversion Driving factors