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Sensitivity studies of a high accuracy surface modeling method

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Science China Earth Sciences 2014年第10期57卷 2386-2396页

作者： ZHAO Na YUE TianXiang ZHAO MingWei du zhengping FAN ZeMeng CHEN ChuanFa State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Geomatics College Shandong University of Science and Technology

The sensitivities of the initial value and the sampling information to the accuracy of a high accuracy surface modeling(HASM) are investigated and the implementations of this new modeling method are modified and enhanced. Based on the fundamental theorem of surface theory, HASM is developed to correct the error produced in geographical information system and ecological modeling process. However, the earlier version of HASM is theoretically incomplete and its initial value must be produced by other surface modeling methods, such as spline, which limit its promotion. In other words, we must use other interpolators to drive HASM. According to the fundamental theorem of surface theory, we modify HASM, namely ***, by adding another important nonlinear equation to make it independent of other methods and, at the same time, have a complete and solid theory foundation. Two mathematic surfaces and monthly mean temperature of 1951–2010 are used to validate the effectiveness of the new method. Experiments show that the modified version of HASM is insensitive to the selection of initial value which is particular important for HASM. We analyze the sensitivities of sampling error and sampling ratio to the simulation accuracy of ***. It is found that sampling information plays an important role in the simulation accuracy of ***. Another feature of the modified version of HASM is that it is theoretically perfect as it considers the third equation of the surface theory which reflects the local warping of the surface. The modified HASM may be useful with a wide range of spatial interpolation as it would no longer rely on other interpolation methods.

关键词： HASM spatial interpolation initial value sensitivity accuracy temperature

HASM quantum machine learning

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Science China Earth Sciences 2023年第9期66卷 1937-1945页

作者： Tianxiang YUE Chenchen WU Yi LIU zhengping du Na ZHAO Yimeng JIAO Zhe XU Wenjiao SHI State Key Laboratory of Resources and Environment Information System Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Yanqi Lake Beijing Institute of Mathematical Sciences and Applications Beijing 101408China College of Resources and Environment University of Chinese Academy of SciencesBeijing 101499China College of Land Resources and Environment Jiangxi Agricultural UniversityNanchang 330045China

The miniaturization of transistors led to advances in computers mainly to speed up their *** miniaturization has approached its fundamental ***,many practices require better computational resources than the capabilities of existing ***,the development of quantum computing brings light to solve this *** briefly review the history of quantum computing and highlight some of its advanced *** on current studies,the Quantum Computing Advantage(QCA)seems *** challenge is how to actualize the practical quantum advantage(PQA).It is clear that machine learning can help with this *** method used for high accuracy surface modelling(HASM)incorporates reinforced machine *** can be transformed into a large sparse linear system and combined with the Harrow-Hassidim-Lloyd(HHL)quantum algorithm to support quantum machine *** has been successfully used with classical computers to conduct spatial interpolation,upscaling,downscaling,data fusion and model-data assimilation of ecoenvironmental ***,a training experiment on a supercomputer indicates that our HASM-HHL quantum computing approach has a similar accuracy to classical HASM and can realize exponential acceleration over the classical algorithms.A universal platform for hybrid classical-quantum computing would be an obvious next step along with further work to improve the approach because of the many known limitations of the HHL *** addition,HASM quantum machine learning might be improved by:(1)considerably reducing the number of gates required for operating HASM-HHL;(2)evaluating cost and benchmark problems of quantum machine learning;(3)comparing the performance of the quantum and classical algorithms to clarify their advantages and disadvantages in terms of accuracy and computational speed;and(4)the algorithms would be added to a cloud platform to support applications and gather active feedback from users

关键词： Quantum computing Machine learning Eco-environmental surface High accuracy surface modelling Quantum computational advantage Practical quantum advantage

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A four-band index for both liquid and solid water and its applications in the Aral Sea Basin

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Science China Earth Sciences 2024年第3期67卷 769-788页

作者： Bing YUE Xi CHEN Saibo LI zhengping du John WILSON Junhui YANG Yimen JIAO Shuangyan HUANG Chenghu ZHOU Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Institute of Geographical Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Spatial Sciences Institute University of Southern CaliforniaLos AngelesCA 90089-0374USA

Various investigations have been conducted to analyze the water-coverage area of the Aral Sea and the Aral Sea Basin(ASB). However, the investigations incorporated considerable uncertainty and the used water indices had misclassification problem, which made different research groups present different results. Thus we first ascertain the boundaries of the ASB, the Syr and Amu river basins as well as their upper, middle and lower reaches. Then a four-band index for both liquid and solid water(ILSW) is proposed to address the misclassification problems of the classic water indices. ILSW is calculated by using the reflectance values of the green, red, near infrared, and thermal infrared bands, which combines the normalized difference water index(NDWI) and land surface temperature(LST) together. Validation results show that the ILSW water index has the highest accuracy by far in the Aral Sea Basin. Our results indicate that annual average decline of the water-coverage area was 963 km^(2) in the southern Aral Sea, whereas the northern Aral Sea has experienced little change. In the meanwhile, permanent ice and snow in upper reach of ASB has retreated considerably. Annual retreating rates of the permanent ice and snow were respectively 6233and 3841 km^(2) in upper reaches of Amu river basin(UARB) and Syr river basin(USRB). One of major reasons is that climate has become warmer in ASB. The climate change has caused serious water deficit problem. The water deficit had an increasing trend since the 1990s and its increasing rates was 3.778 billion m^(3) yearly on average. The total water deficit was 76.967 billion m^(3) on average in the whole area of ASB in the 2010s. However, up reaches of Syr river basin(USRB), a component area of ASB, had water surplus of 25.461 billion m^(3). These conclusions are useful for setting out a sustainable development strategy in ASB.

关键词： Aral Sea Basin Syr river basin Amu river basin Water indices Water-coverage area Water deficit Climate change

Development of a surface modeling method for mapping soil properties

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Journal of Geographical Sciences 2012年第4期22卷 752-760页

作者： SHI Wenjiao LIU Jiyuan du zhengping YUE Tianxiang Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China

High accuracy surface modeling （HASM） is a method which can be applied to soil property interpolation. In this paper, we present a method of HASM combined geographic information for soil property interpolation （HASM-SP） to improve the accuracy. Based on soil types, land use types and parent rocks, HASM-SP was applied to interpolate soil available P, Li, pH, alkali-hydrolyzable N, total K and Cr in a typical red soil hilly region. To evaluate the performance of HASM-SP, we compared its performance with that of ordinary kriging （OK）, ordinary kriging combined geographic information （OK-Geo） and stratified kriging （SK）. The results showed that the methods combined with geographic information including HASM-SP and OK-Geo obtained a lower estimation bias. HASM-SP also showed less MAEs and RMSEs when it was compared with the other three methods （OK-Geo, OK and SK）. Much more details were presented in the HASM-SP maps for soil properties due to the combination of different types of geographic information which gave abrupt boundary for the spatial varia- tion of soil properties. Therefore, HASM-SP can not only reduce prediction errors but also can be accordant with the distribution of geographic information, which make the spatial simula- tion of soil property more reasonable. HASM-SP has not only enriched the theory of high accuracy surface modeling of soil property, but also provided a scientific method for the ap- plication in resource management and environment planning.

关键词： high accuracy surface modeling (HASM) spatial interpolation accuracy geostatistics soil properties red soil hilly legion in South China

A new horizon for neuroscience:terahertz biotechnology in brain research

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Neural Regeneration Research 2025年第2期20卷 309-325页

作者： zhengping Pu Yu Wu Zhongjie Zhu Hongwei Zhao Donghong Cui Shanghai Key Laboratory of Psychotic Disorders Shanghai Mental Health CenterShanghai Jiao Tong University School of MedicineShanghaiChina Department of Psychiatry Kangci Hospital of JiaxingTongxiangZhejiang ProvinceChina Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of ScienceShanghaiChina National Facility for Protein Science in Shanghai Shanghai Advanced Research InstituteChinese Academy of SciencesShanghaiChina

Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain *** this article,we review the development of terahertz biotechnology and its applications in the field of *** evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin *** vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric *** the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic ***,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical *** review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages.

关键词： biological effect brain neuron neuropsychiatry neuroscience non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology

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等高线树构建及高保真DEM构建

中国图象图形学报 2011年第7期16卷 1255-1261页

作者：宋敦江岳天祥杜正平中国科学院科技政策与管理科学研究所北京100190 中国科学院地理科学与资源研究所北京100101

研究正负地貌等高线(含未闭合等高线)的空间关系。首先将未闭合等高线分为完全开放等高线和贴边等高线,分别进行自动闭合处理。然后使用多边形叠加分析的方法判断闭合等高线之间的关系,构建等高线树。通过对等高线树结构的遍历,获取格... 详细信息

研究正负地貌等高线(含未闭合等高线)的空间关系。首先将未闭合等高线分为完全开放等高线和贴边等高线,分别进行自动闭合处理。然后使用多边形叠加分析的方法判断闭合等高线之间的关系,构建等高线树。通过对等高线树结构的遍历,获取格网点高程值的上下界,将上下界输入到高精度曲面建模区域优化控制方法进行约束优化控制模拟,能保证模拟结果的回放等高线与原始等高线的最大距离不超过一个栅格的宽度。最后对高斯合成曲面和扫描矢量化等高线两个实例进行论证。

关键词：等高线树正地貌负地貌高精度曲面建模区域优化控制等高线回放

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高精度曲面建模最佳表达形式的数值实验分析

地球信息科学 2006年第3期8卷 83-87页

作者：岳天祥杜正平中国科学院地理科学与资源研究所北京100101

高精度曲面建模的发展过程在理论上可归结为对高斯方程组中单个方程不同组合的数值模拟分析比较和检验过程。数值实验分析结果表明,因有限差分所带来的数值困难,高斯方程组中的交叉项方程是影响高精度曲面建模误差和模拟速度的关键因素... 详细信息

高精度曲面建模的发展过程在理论上可归结为对高斯方程组中单个方程不同组合的数值模拟分析比较和检验过程。数值实验分析结果表明,因有限差分所带来的数值困难,高斯方程组中的交叉项方程是影响高精度曲面建模误差和模拟速度的关键因素,高精度曲面建模的最佳数学表达是除交叉项方程之外的其他两个方程的组合。

关键词：高精度曲面建模计算时间模拟误差

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肾移植术后早期急性排斥反应84例回顾分析

广东医学 2005年第4期26卷 481-483页

作者：杜正平于立新南方医科大学南方医院器官移植中心广州510515

目的　探讨肾移植早期急性排斥反应的危险因素、诊断、鉴别诊断及治疗。方法　肾移植4 2 8例中对84例(19 6 % )发生早期(1个月内)急性排斥反应的危险因素、诊断及治疗进行回顾性分析。结果　84例早期急性排斥反应经治疗后,82例成功,2例... 详细信息

目的　探讨肾移植早期急性排斥反应的危险因素、诊断、鉴别诊断及治疗。方法　肾移植4 2 8例中对84例(19 6 % )发生早期(1个月内)急性排斥反应的危险因素、诊断及治疗进行回顾性分析。结果　84例早期急性排斥反应经治疗后,82例成功,2例失败,移植肾均于术后短期予以摘除,对2例在短期内作了再次移植,均取得成功。结论　急性排斥反应仍是各类排斥反应最常见的一种,目前对早期急性排斥反应的治疗是肾移植成功的关键。

关键词：肾移植术后急性排斥反应危险因素诊断鉴别诊断治疗

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引入第二种共聚单体的聚乙烯产品性能

塑料工业 2023年第12期51卷 103-109页

作者：杜正平周文忠郝雪丽国家能源集团宁夏煤业有限责任公司烯烃二分公司宁夏银川750004

采用共聚改性对聚乙烯产品进行改性,具体方式为在聚乙烯主链上引入共聚单体1-丁烯的同时引入少量丙烯。通过不断增加丙烯量同时减少等量的1-丁烯,探究了在不同丙烯进料量下聚乙烯产品的各项指标及性能。引入丙烯后,聚乙烯反应活性由初始... 详细信息

采用共聚改性对聚乙烯产品进行改性,具体方式为在聚乙烯主链上引入共聚单体1-丁烯的同时引入少量丙烯。通过不断增加丙烯量同时减少等量的1-丁烯,探究了在不同丙烯进料量下聚乙烯产品的各项指标及性能。引入丙烯后,聚乙烯反应活性由初始的427 kg(PE)/(gTi·h)提升至529 kg(PE)/(gTi·h),峰值出现在丙烯进料量为0.6 t/h处。聚乙烯产品堆积密度由之前的0.311 g/cm^(3)增长至0.379 g/cm^(3),聚乙烯堆积密度峰值同样出现在丙烯进料量为0.6 t/h处。在此处,均聚聚乙烯的分子间隙中生成了乙丙橡胶相,产品拉伸断裂应力最大,而熔体质量流动速率受生成橡胶相影响并未升高。聚乙烯产品雾度则是随着引入丙烯含量增多而线性递减。

关键词：共聚改性聚乙烯橡胶相共聚单体支链