基于光谱指数的区域土壤盐分三维空间变异研究

为揭示中原黄泛区土壤盐分三维空间分布特点,以河南省封丘县为研究区域,综合应用土壤采样数据与遥感影像数据,利用光谱指数法与三维反距离权重法(IDW)对三维土壤盐分空间变异特征进行了解析与评价,显著提升了区域土壤盐分的三维预测精度。研究区域土壤电导率变异系数在0.218～0.324之间,属中等变异强度;各层土壤电导率的平均值在0.121～0.154 ds·m-1之间,土壤盐分高值区主要分布在天然渠与黄河沿线区域,研究区盐渍土剖面类型属“底聚型”,即随着深度增加土壤盐分含量逐渐增大,呈现底土积盐的趋势;该研究表明应用以光谱指数数据为基础的三维IDW方法对区域土壤盐分三维特征进行解析可以达到较高精度。该研究为中原黄泛区盐渍障碍耕地的治理利用提供了可靠技术方法。     

植被冠层水平叶绿素含量的高光谱估测

植物的叶绿素含量指示了其健康状况。大区域范围内植被叶绿素含量信息的提取可以用于评价植被的生长状况,实现对生态环境的监测。对于农田系统而言,作物叶绿素含量的估测还可以对施肥等田间操作提供支持。文章利用辐射传输模型模拟多组不同状态下的植被冠层光谱反射率,通过对模拟数据的冠层叶绿素含量以及冠层光谱之间关系的分析,构建了估测植被冠层水平叶绿素含量的光谱指数模型。该模型对冠层叶绿素含量的方差解释量达到了75%以上。分别使用野外实测冠层光谱和Hyperion高光谱遥感影像对试验区进行验证。结果证明该模型对冠层水平的叶绿素含量估测效果较好,具有应用价值。     

Beltrami-de Sitter时空和de Sitter不变的狭义相对论

分析了在相对论体系中狭义相对性原理和宇宙学原理之间的关系以及Beltrami-de Sitter -陆启铿疑难.指出可以把狭义相对性原理推广到非零常曲率时空，在具有Beltrami度规 的de Sitter/反de Sitter时空中建立狭义相对论的运动学和粒子动力学. 在这类狭义相对 论中,相对于Beltrami坐标同时性，Beltrami坐标系就是惯性坐标系，相应的观测者为惯 性观测者; 对于自由粒子和光讯号, 惯性定律成立;可以定义可观测量,它们不但守恒而且还 满足推广的爱因斯坦关系.除了Beltrami坐标时同时性之外，对于共动观测, 还可以取固 有时同时性;此时，Beltrami度规成为Robertson-Walker型的度规，其3维空间是闭的,对 于平坦的偏离为宇宙学常数的量级.这表明,在这类狭义相对论中,相对性原理与“完美”宇 宙学原理之间存在内在联系,并不存在那些问题.进而,基于最新观测事实，重述了Mach原 理；指出对于Beltrami-de Sitter/反de Sitter时空，宇宙学常数恰恰给出惯性运动的起 源. 关键词： 狭义相对性原理 宇宙学原理 de Sitter不变的狭义相对论 Beltrami-de Sitter时空 同时性 Mach原理     

利用MODIS图像反演中国近海海域的气溶胶光学特性

针对中国近海海域的水体大多是混浊水体和其上空有较多吸收性气溶胶的情况,提出了适合反演该区域上空气溶胶光学特性的新算法.该算法利用多个查找表和基于经验得到下垫而为等效干净水体的晴空图像,采用插值方法实现了对中国近海海域上空气溶胶光学特性的反演.经过在东山岛地区同地面同步观测多次实验对比,结果发现该算法可行且具有较高的精度;并以渤海湾地区为例,进行了初步的反演应用研究.该算法不仅能为我国海洋和风云系列卫星资料的大气校正研究提供相关的技术基础,还可以直接利用刚发射的FY-3卫星上的CMODIS数据来反演近海海域的气溶胶光学特性.     

应用随机模型方法预测汽车风噪声

采用随机模型方法,对简化汽车头部外形进行风噪声数值模拟.将计算区域分为声源区域和传播区域,在声源区域采用随机模型构造湍流脉动速度场,传播区域通过求解带源项的线化欧拉方程实现声波向外传播得到声场解.同直接模拟方法相比,该方法具有计算量小、计算所需内存少等优点.数值模拟结果与实验数据吻合较好,验证了该方法预测汽车风噪声的可行性,为研究实际汽车外形的风噪声问题打下基础.     

素因子分解FFT算法及其指数映射

本文研究了一类素因子分解ＦＦＴ算法的指数映射，用这些指数映射方法可以构成一类新的素因子分解ＦＦＴ算法（ＰＦＡ）。此类算法可以用非同址的方式实现，也可以用同址的方式实现；既可以输入输出皆为同一顺序而不需要混序，也可以输入输出不为同一顺序而需要混序。本类算法具有新的算法结构，在计算每一维的小点数ＤＦＴ时，需要变换数据模块的地址。理论分析与计算机仿真实验表明，新算法不仅保持了传统ＰＦＡ［３］能够节省存贮量、提高运算速度的优点，而且具有可以顺序输入输出、同址计算、无需混序操作的特点。     

基于光谱指数法的植被含水量遥感定量监测及分析

在分析植被光谱特征与光谱和植被水分相关性的基础上,初步确定几个波段或波段组合为植被含水量的光谱指数.利用数据对植被含水量FMC(Fuel Moisture Content)与上述水份光谱指数分别建立最优函数关系.通过分析不同光谱指数的关系及其相对误差,确定以1600 nm和820 nm处反射率的比值SR作为建立本研究区植被含水量模型的特征参数;并利用实测光谱反射率与植被含水量建立SR与FMC之间的模型关系.根据植被含水量模型、ETM和ASTER遥感数据.在IDL7.0开发平台下实现研究区植被含水量的定量反演,并利用区内实测数据和本底调查数据对反演结果进行了综合评价与分析.结果表明,光谱指数SR可以较好地剔除环境背景以及冠层结构等外界因素的影响,植被含水量遥感反演精度较高,能真实反映研究区植被含水量的时空变化规律与特征.     

利用牛顿环装置测量平玻璃折射率

在牛顿环实验装置半透半反镜和移测显微镜物镜之间垂直光路位置放置待测平玻璃,改变平玻璃倾角,使干涉条纹产生水平位移,测量水平位移和倾角之间的关系,通过数据拟合测出平玻璃折射率的大小.该方法的关键是平玻璃倾角和水平微小位移的准确测量.实验中充分利用实验室现有条件组装角度测量仪测量倾角,利用牛顿环高精度移测显微镜以干涉环为参照读取微小位移,实现了对折射率较高精度的测量.     

基于△Ts-Albedo光谱信息的土壤水分监测新指数研究

土壤水分的遥感监测在农业干旱和水资源管理方面具有重要的意义.利用MODIS反射率和温度产品来获取地表昼夜温差(△Ts)和宽波段反照率(Albedo),构建△Ts-Albedo光谱特征空间,提出温差-反照率干旱指数(temperature difference albedo drought index,TDADI)用来监测土壤水分,并利用宁夏实测0～10cm平均土壤含水量数据验证该指数的精度,结果表明:它们之间的相关性较好,R2变化范围为0.36～0.52.TDADI与TAD/相比,该指数具有更高的土壤水分监测精度.然而,由于数据获取的局限性,只采用了宁夏平原数据对TDADI进行验证,在其他区域仍需要进一步验证.     

量子光学中的一种新变换

我们发现量子光学理论中一个新的积分变换,它不但能够反映量子光学中的Baker-Hausdorff公式的功效,而且可以实现相空间多项式和纠缠态的函数空间之间的变换.此变换可逆,且满足类Parseval定理.在相空间中结合Wigner变换和此新积分变换,可以得到相空间函数h(p,q)和其Weyl-Wigner对应算符之间的一个新的积分变换公式.     

Advantage of populous countries in the trends of innovation efficiency

A flurry of studies indicates that population size has a positive effect on innovation, however, cross-country empirical evidence remains sparse. In this paper, we add to the literature by investigating the relationship between population size and innovation efficiency at the country level through constructing three relative indexes based on the datasets of patent applications and Research and Development (R&D) investment. Different from previous studies based on absolute innovation indicators, the relative indexes can reflect the core innovation efficiency of economies by excluding the impact from the difference of economic development level, with a view putting all economies into a comparable standard framework. For all of the three relative indexes, their long-term trends show significant correlations with population size, and the economy with a larger population usually has better and stable performance on the trends of innovation efficiency. In addition, we find that there is a critical population size, over which the economy would be more likely to have a spontaneous improvement on innovation efficiency. This study provides direct evidence in supporting the population size advantage on the trends of innovation efficiency at the economy level and provides new insight to understand the rapid development of innovation in a few populous countries.     

Spatial Correlation Network and Regional Differences for the Development of Digital Economy in China

The rapid development of the digital economy is a powerful driving force to promote high-quality economic growth all over the world. Although a number of studies have been conducted to investigate the development of the digital economy in China, these studies pay little attention to the spatial linkages between the 30 provinces in China and the developmental differences between northern and southern China. Using Chinese digital economic data from 2004 to 2019, we propose an index system to measure the developmental levels of the digital economy and obtain the annual developmental levels of these provinces by using the factor analysis method. We analyze the regional differences of developmental levels by using the Theil index and kernel density estimation method. More importantly, the network method is used to analyze the correlations between the developmental levels of the digital economy in all provinces of China. By decomposing regional differences, our study shows that polarized and uncoordinated development is prominent. The development level of the digital economy in the southern region is higher than that in the northern region. In terms of regional correlations, the network study suggests that there are beneficial and spillover effects of the digital economy development between provinces. Based on the analysis results, we propose policies for improving the development of the digital economy in China.     

Sustainable Development and Spatial Inhomogeneities

Historical data, theory and computer simulations support a connection between growth and economic inequality. Our present world with large regional differences in economic activity is a result of fast economic growth during the last two centuries. Because of limits to growth we might expect a future world to develop differently with far less growth. The question that we here address is: “Would a world with a sustainable economy be less unequal?” We then develop integrated spatial economic models based on limited resources consumption and technical knowledge accumulation and study them by the way of computer simulations. When the only coupling between world regions is diffusion we do not observe any spatial unequality. By contrast, highly localized economic activities are maintained by global market mechanisms. Structures sizes are determined by transportation costs. Wide distributions of capital and production are also predicted in this regime.     

The “S” curve relationship between export diversity and economic size of countries

The highly detailed international trade data among all countries in the world during 1971-2000 shows that the kinds of export goods and the logarithmic GDP (gross domestic production) of a country have an S-shaped relationship. This indicates that all countries can be divided into three stages accordingly. First, the small economies always export very few kinds of products as we expect. Second, once the economic size magnitude (log(GDP)) of a country is beyond a threshold, its export diversity may increase dramatically. However, this is not the case for large economies because a ceiling on the export diversity is observed when their logarithmic GDPs are higher than another threshold. This pattern is very stable for different years although the concrete parameters of the fitting sigmoid functions may change with time. In addition, we also discussed other relationships such as import diversity with respect to logarithmic GDP, diversity of exporters with respect to the number of export goods etc.; all of these relationships show S-shaped or power law patterns which can be derived by the “S” curve relations. Although this paper does not explain the origin of the S-shaped curve, it may provide a basic empirical fact and insights for economic diversity.     

Nuclear relativistic technologies for energy production and utilization of spent nuclear fuel: Results of first experiments on substantiation of nuclear relativistic technologies

A fundamentally new scheme of the electronuclear method based on nuclear relativistic technologies is discussed; this scheme includes the formation and utilization of a limiting hard neutron spectrum in the volume of the deep subcritical active core. It is demonstrated that the development and application of nuclear relativistic technologies can be promising for solving the problem of utilizing spent nuclear fuel and global challenges of power production. The results of the first experiments performed at the Joint Institute for Nuclear Research indicate the realistic character of the main principles of relativistic nuclear technologies, in particular, the growth of beam-power amplification by a factor of 2 for a deuteron beam irradiating a massive (315 kg) uranium target with the beam energy increasing from 1 to 4 GeV.     

基于鹰鸽量子博弈理论评价科研院所的科技自主创新能力

科研院所的科技自主创新能力是推动国家科技进步和经济发展,应对国际经济危机的主要动力,创建科学、完善的科技创新能力评价方法有助于提升科研院所科技创新能力,并为国家制定科技创新决策提供参考依据。本文基于鹰鸽量子博弈理论,提出了一种评价科研院所自主创新能力的方法。介绍了量子博弈论的各基本要素在科技自主创新体系中所对应的物理内涵,根据鹰鸽量子博弈理论建立了科技自主创新能力评价模型,分析了纠缠度与收益矩阵之间的关系,确立了依靠各参与者在鹰鸽量子博弈中的纠缠度来表征科技自主创新能力的方法。给出了科研院所科技自主创新能力的量子博弈论解释,构建了科技自主创新能力评价指标体系,并确定了评价的合成计算方法,即量子纠缠度的计算方法。最后,以中科院部分研究所为实例进行了科技自主创新能力的评价,并利用主成份分析法和中物院的简单统计方法对得到的数据进行了对比分析,结果证明了提出的方法合理且有可操作性。     

New Measure of Economic Development Based on the Four-Colour Theorem

The location quotient is one of the basic quantitative tools for identifying the regional poles and the turnpikes of economic growth in spatial economy. The disadvantage of this traditional measure is the limited scope of economic information contained in it. The new measure of economic development proposed in the article encompasses a complex spectrum of phenomena in one number, as it takes into account the influence of the public administration sector, as well as top technology in the form of ICT and its practical business models. It also takes into account the digital prosumption and the platforms for participation. The participation platforms in the public administration sector are the websites of municipal public administration offices. A cluster analysis was used to distinguish four quality classes of these websites. These classes were assigned four different colours, which were then used to draw up a map of the selected province. Each municipality is marked with a colour that corresponds to the quality class of the website of the state administration office operating on its territory. The colour system resulting from the four-colour theorem and the corresponding dual graph play the role of a reference system in relation to each empirical colour distribution and another dual graph related to it. The measure of the economic development of a region is the degree of reduction of the dual graph corresponding to the empirical distribution of colours, which identifies the actual growth poles and determines the routes of growth. The presented indicator better and more precisely identifies poles and routes of economic growth than the traditional location quotient.     

小麦生长过程中光能利用率和光化学反射指数的相关性研究

以不同品种的小麦为材料,同时测量小麦生长过程的光谱反射率和光能利用率,研究了小麦整个生长期内光化学反射指数和光能利用率之间的关系变化,讨论二者之间关系的时间效应.实验结果表明,对小麦的整个生长期,光化学反射指数并不能作为估算光能利用率的一个有效指数.由于叶片叶绿素含量和叶面积指数的影响,在小麦的生长初期和末期,光化学反射指数和光能利用率之间的相关性不高,相关系数R2分别为0.222 4和0.210 6.对于小麦生长力旺盛的阶段,光化学反射指数可以作为估算光能利用率的一个可行方法,能够获得一定准确度的光能利用率,相关系数R2分别为0.612 7、0.641 2和0.601 1.     

X射线掠入射显微成像诊断技术研究进展

高精密的X射线成像诊断是深入理解内爆过程，揭示点火尺度下未知物理问题的关键。基于掠入射反射的X射线显微镜，结合亚纳米级的超光滑球面或非球面反射镜，能够实现空间分辨优于5 μm的高分辨成像。介绍了国际惯性约束聚变领域的X射线显微成像技术发展及应用，重点展示了我国在高分辨X射线（KB）显微镜、多通道X射线KB显微镜以及大视场X射线KBA显微镜方向的进展，分析了下一阶段超高分辨X射线显微成像的研究计划。通过不断的技术创新，我国的X射线显微成像诊断能力已经达到国际先进水平。     

Routh Order Reduction Method of Relativistic Birkhoffian Systems

Routh order reduction method of the relativistic Birkhoffian equations is studied.For a relativistic Birkhoffian system,the cyclic integrals can be found by using the perfect differential method.Through these cyclic integrals,the order of the system can be reduced.If the relativistic Birkhoffian system has a cyclic integral,then the Birkhoffian equations can be reduced at least by two degrees and the Birkhoffian form can be kept.The relations among the relativistic Birkhoffian mechanics,the relativistic Hamiltonian mechanics,and the relativistic Lagrangian mechanics are discussed,and the Routh order reduction method of the relativistic Lagrangian system is obtained.And an example is given to illustrate the application of the result.