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131.
根据“三个代表”的思想 ,社会主义宪法应该代表先进生产力的发展要求。中国的宪法发展说明 ,什么时候代表了中国先进社会生产力发展的要求 ,什么时候中国宪法就能健康发展 相似文献
132.
133.
本文介绍一种无线数据传接口及控制装置。装置中采用计算机软件实现串—并、并—串变换及频率调制、其硬件成本低廉,工作可靠,可用于速率为50、300、600或1200bps的数传通信。 相似文献
134.
健康是影响不同国家和地区发展的关键因素,全面了解“一带一路”成员国的居民健康状况,是探讨“一带一路”成员国之间健康医疗合作的重要基础。本文选择了4个代表性的健康状况指标(出生期望寿命、总生育率、过早非传染性疾病死亡率和结核病发病率),利用Moran's I指数、Getis-Ord G指数对“一带一路”135个成员国的健康状况进行时空统计,分析了健康状况的空间相关性和空间分布模式,研究了健康状况的时空格局。研究发现:① 2000—2016年“一带一路”大部分成员国的各项健康状况指标均朝着改善和优化方向发展;健康状况指标均呈现显著的正空间自相关性;② 总体而言,在“一带一路”成员国中,欧洲国家的居民健康状况最好;南北美洲和大洋洲国家的居民健康状况良好;亚洲国家的居民健康状况总体良好,但东南亚部分国家的结核病发病率较高;非洲国家的居民健康状况虽有明显改善,但仍处于较低状态。因此,“一带一路”成员国应进一步加强健康医疗合作,共同推动健康丝绸之路的发展。 相似文献
135.
Modelling the flexural buckling failure of stratified rock slopes based on the multilayer beam model
The buckling failure of stratified rock slopes intersected by a set of steep discontinuities that are approximately parallel to the slope surface is frequently encountered while constructing railways and roadways in mountainous areas. In this study, an analytical approach based on the energy equilibrium principle is presented to solve the flexural buckling stability of stratified rock slopes within the framework of multilayer beam theory. The generalized HoekBrown failure criterion is introduced to reflect the influences of slope size(scale effects) on the buckling stability. Subsequently, numerical and physical modellings from previous literatures are employed to validate the proposed approach. Furthermore, a practical case of Bawang Mountain landslide is also used for the comparative analysis. The study shows that the present analytical approach is capable to provide a more reasonable assessment for the buckling failure of stratified rock slopes, compared with several existing analytical approaches. Finally, a detailed parametric study is implemented, and the results indicate that the effects of rock strength, rock deformation modulus, geological strength index, layer thickness and disturbance degree of rock mass on the buckling failure of stratified rock slopes are more significant than that of rock type and slope angle. 相似文献
136.
为了解乌鲁木齐冬季污染天气形成过程中大气颗粒物化学组分的变化,探讨霾天气快速形成的主要原因,应用扫描电镜/X射线能谱仪(SEM/EDX)对2013年2月乌鲁木齐东南郊一次典型霾天和正常天气所采集的大气颗粒物(PM10)样品进行了微观形貌和化学组成的对比分析。结果表明:伴随着霾形成过程细粒子浓度呈现急剧上升趋势,PM1.0/PM10比值高达0.77。SEM/EDX观测显示,霾天形成前后,PM10的形态结构和元素组成存在较明显的差异,霾天规则的石膏颗粒占规则颗粒的71.1%,明显高于正常天气,表明大气颗粒物的硫化现象比较普遍,大量硅铝酸盐飞灰说明采样点周边有较明显的燃煤源输送;二次无机颗粒组成主要为硫酸盐颗粒,由正常天气的16.1%增加到24.6%,高浓度硫酸盐与乌鲁木齐东南郊此次霾形成有密切的联系。 相似文献
137.
Casey D. SULLIVAN CHEN Pengju Justine Shanti ALEXANDER BAI Defeng SHI Kun 《资源与生态学报(英文版)》2018,9(5):554-565
Human-wildlife conflict (HWC) is a global conservation issue of increasing concern, and understanding the factors driving conflict is crucial for preventing or mitigating it. In many parts of China, large human populations and increasing development has led to an escalation in HWC with both carnivore and prey species. In this paper we assess herder attitudes toward blue sheep (Pseudaois nayaur, Hodgson, 1833), white lipped deer (Carvus albirostris, Przewalski, 1883), red deer (Cervus elaphus, Linnaeus, 1758), and marmot (Marmota himalayana Hodgson, 1841) through interview-based surveys conducted in 46 households across 8 villages in Qilianshan National Nature Reserve, Gansu, China. We also examine the perceived impact of three ecological-restoration policies (anti-grazing, sustainable grazing, and grass-planting policies) on livelihoods, and how this affects attitudes toward wildlife. Herders reported neutral attitudes toward wildlife species in general, but reported negative attitudes towards blue sheep. Mixed-effects modeling revealed that herder attitudes toward the target species varied significantly across villages, but other socioeconomic variables had limited explanatory power for attitudes. Furthermore, we found that while policy implementation was negatively perceived by herders, anti-grazing policy implementation and total policy implementation were positively correlated with positive attitudes toward wildlife, highlighting a potential gap between perceived threats and actual threats. Finally, we show that the leading cause of reported livestock death is preventable disease, alleviation of which may help improve attitudes toward wildlife. 相似文献
138.
地理认知理论内涵分析 总被引:18,自引:2,他引:18
在分析现有地理信息系统以及地理专家系统的研究特点之后,提出对于以研究和模拟地理学家的逻辑思维方式为目的的“地理认知理论”进行了研究。 相似文献
139.
M. Kun † J. Vinkó ‡ L. Szabados 《Monthly notices of the Royal Astronomical Society》2000,319(3):777-790
In order to reveal the star-forming history of the molecular cloud complex we studied the intermediate mass stellar population in the Cepheus Flare region. (Paper I dealt with the distance and the young stellar object candidates of the region.) Correlating the IRAS Point Source Catalogue and Faint Source Catalogue positions with those of 1214 B8–A8 and 1760 F0–F5 type stars brighter than and classified during an objective prism survey, we identified 19 stars showing far-infrared excess emission in the Cepheus Flare region. In addition to the 16 stars whose counterparts are given in the IRAS catalogues, we found three more stars with infrared excess not recognized before. In order to identify the young medium-mass stars associated with the Cepheus Flare molecular clouds we observed the optical spectra of the IR-excess stars, and using published optical photometry and the IRAS data we examined their spectral energy distributions (SEDs) and IRAS two-colour diagram. The observations resulted in the discovery of a new Herbig Ae/Be star, BD +68°1118, coinciding with IRAS 21169+6842. More evolved HAe/Be stars may be SAO 19953, BD +67°1314 and BD +69°1231, whose H α lines showed weak emission components. Possible β Pictoris- or Vega-type stars may be HD 203854, HD 212826 and HD 216486, whereas the far-infrared fluxes at the positions of BD +72°1018, HD 210806 and HD 217903 can be attributed to the heating of the interstellar environment. We used distances and radial velocities of the stars derived from the spectroscopy and published optical photometry as indicators of their relations to the clouds. Information on the environment of the observed stars deduced from the diffuse interstellar band at λ 6613 is briefly discussed. 相似文献
140.
兼顾生态保护和经济增长的生态安全网络对引导滨水城市走可持续发展道路具有重要指导意义。本文以九江市为例,采用景观生态数据集和产业信息数据集,结合最小累积阻力模型(MCR)和连续空间的产业集聚测度指数(DO)构建了综合评价方法,分别对景观生态格局和经济生产空间进行分析,诊断二者的空间冲突确定战略节点并构建生态安全网络。结果表明:① 研究区包含重要生态源地29个,总面积为7323 km2;生态安全阻力高值区面积占39.69%,位于城市中部和东部连片区域,低值区则处于外围,且连通过渡区域较少,呈现空间上两极分化的“中心—外围”景观生态格局;② 经济生产空间临近水资源分布,呈现为小尺度集聚、大尺度分散的空间格局;主要产业集聚区的平均长度和数量均显示出重度污染行业>轻度污染行业>中度污染行业的空间关系;③ 识别出景观生态廊道总长685.57 km,选取了25个生态—经济战略节点,规划了18条总长424.53 km的重要绿带和26条总长662.46 km的一般绿带,共同构成了“蜂巢状”九江市生态安全网络格局。本文采用自然和经济条件相结合的综合分析视角,为生态安全格局的构建提供了多样化的实现途径。 相似文献