全球价值链视角下中国与印度信息产业国际竞争力的比较分析     

耿溪谣  胡洋 《世界地理研究》2022,31(2):270-279

信息产业是推动国民经济发展的重要引擎,也关乎国家未来的发展前景。目前,无论是发达国家还是新兴工业化经济体,都将提升信息产业竞争力作为关注焦点。中国和印度均高度重视信息产业,但在促进产业发展的策略和模式上截然不同。基于全球价值链的视角,运用附加值贸易数据测算中、印两国信息产业在全球价值链中的参与程度和分工地位,并从国家产业政策和区位条件的角度比较两国信息产业融入全球价值链的机制和效果。研究发现：加强“硬件”制造能显著提升中国信息产业的国际竞争力,而“软件”优先的政策导向并未改善印度信息产业的整体实力,中国优先发展“硬件”并兼顾“软件”的产业政策更有利于信息产业的高质量、可持续发展。从区位条件来看,印度缺乏全面发展“硬件”制造的基础条件,中国则为“硬件”制造和“软件”服务创造了良好的发展空间。  相似文献   

苏皖北部地区晚元古代地层的马尔柯夫链分析     

王翔 《地球科学与环境学报》1988,(2)

本文运用数学地质理论中的马尔柯夫链分析方法,对苏皖北部地区及鲁西南地区晚元古代地层进行了初步研究。文中选择6条比较典型的剖面,分别对它们进行了转移概率、极限概率、差值阵、置换分析和熵分析等方面的计算,并对所得结果做了相应的地质解释。分析结果,从定量方面揭示出了晚元古代时期苏皖海盆基底的“波动”史及其上覆地层的主要沉积韵律类型,以及盆地内不同部位、不同时代岩性变化的主要趋势及其阶段性;并认为,在晚元古代早期苏皖海盆中很可能同时存在有南、北两个沉积中心,而并非像以往所认为的那样,只有一个沉积中心。  相似文献   

一个简易的CRM系统的设计与实现--汽修连锁资源管理系统     

崔冬霞  蔡淮 《成都信息工程学院学报》2004,19(4):507-510

首先提出引入CRM和连锁经营的必要性和紧迫性,并分析了国内外现状,接着对客户关系管理和连锁经营的基本概念及其相关理论进行阐述,最后具体实现这个系统,包括硬件架构和软件模型.  相似文献   

Statistical properties of the number of runs of matches between two random stratigraphic sections     

J. Vrbik 《Mathematical Geology》1985,17(1):29-40

A quantity based on the number of runs of matches between two lithological sequences is suggested as an alternative or a supplement to the coefficient of cross-association. It is shown that, in many practical situations, the proposed random variable can serve as a more sensitive indicator of nonrandom similarities between two such sequences. Formulas pertaining to its asymptotic properties under the assumption of independence are derived.  相似文献   

大洋调查中海山地磁测量的静日变化校正方法   总被引：2，自引：1，他引：1       下载免费PDF全文

刘保华  刘晨光  裴彦良  阚光明 《海洋学报》2008,30(6):94-98

针对大洋调查中海山地磁测量时难以设立静日变化观测站的问题,提出了一种基于多项式拟合最小二乘算法的日变校正方法,即假设静日变化磁场可以用一个关于时间的高阶多项式来拟合,利用主测线和联络测线交点误差的最小二乘估计求得多项式的系数,从而得到静日变化曲线。从调查测得的磁场中减掉静日变化磁场即可得消除静日变化影响后的海山地磁异常。理论模型和实际资料处理都表明,这种方法不仅可以较好地消除静日变化的影响,而且用计算机实现也简单。为了提高静日变化校正结果,讨论了为提高静日变化校正效果,在大洋调查中测量海山地磁时应注意的几个问题。  相似文献   

中太平洋海山区富钴结壳构造与地球化学特征及意义     

崔迎春  任向文  刘季花  石学法  尹京武  郝金华 《海洋科学进展》2008,26(1):35-43

为了释读蕴藏在富钴结壳中的环境变化信息,运用电子探针技术对中太平洋海山CXD05结壳进行了详细的构造和地球化学研究.结果表明:1)CXD05结壳约从19.4 Ma BP(早中新世)开始发育,从基部至顶部依次发育了斑杂构造、柱状构造和纹层构造;2)结壳中亲氧元素和碎屑组分从老至新发生规律性变化.结壳构造序列反映了其生长过程中海洋动力环境能量由高到低的变化;而壳层亲氧元素和碎屑组分的变化则记录了海水的氧化程度和风尘影响强度的变化.  相似文献   

Sequence analysis and quantitative detection of Norwalk-like viruses in cultured oysters of China     

Jun Wang  Qingjuan Tang  Zhiqin Yue  Zhaojie Li  Jin Zhang  Changhu Xue 《中国海洋大学学报(英文版)》2008,7(2):223-227

We isolated 4 Norwalk-like viruses (NLVs) contaminated oysters from 33 Chinese oysters collected from local commer-cial sources of Shandong Province. After amplification of the RNA-dependent RNA polymerase (RdRp) region of NLVs genomes with RT-PCR, the open reading frame 1 (ORF1) of the RdRp was sequenced and subjected to multiple-sequence alignment. The re-suits showed that NLVs in the four isolates belong to genogroup Ⅱ. The sequence comparison showed that the similarity between four Chinese oyster isolates were higher than 99.0%, which indicated that NLVs prevalent in close areas have high homogeneity in genome sequences. In addition, the most conserved sequences between diverse NLVs were used to design primers and TaqMan probes, then the real-time quantitative PCR assay was performed. According to the standard curve of GII NLVs, the original amounts (copies) of NLVs in positive patient's fecal isolate, positive Japanese oyster isolate, and the Chinese oyster isolate were 8.9×108, 1.25×108 and 4.7×101 respectively. The detecting limit of NLVs was 1×101 copies. This study will be helpful for routine diagnosis of NLVs pathogens in foods and thus for avoiding food poisoning in the future.  相似文献   

基于Servlet服务链的分布式Web GIS研究     

陈静  汪小蔓 《测绘科学》2007,32(3):94-95,98

本文从Servlet技术出发,探讨了Servlet技术在Web GIS服务器实现上的优势。针对目前分布式Web GIS中面临的数据和信息的分布存储、地理信息难以整合、多用户并发访问瓶颈等问题;探讨了通过构建Servlet服务链来实现分布式Web GIS的体系架构,基于Servlet服务链的分布式空间数据的调度与管理,Web GIS服务器端GIS Servlet服务链的构建。最后,通过实验验证了多Servlet服务链在Web GIS中分布数据处理,服务中多用户并发访问等方面的优势。  相似文献   

Deformation history and processes during accretion of seamounts in subduction zones: The example of the Durkan Complex (Makran,SE Iran)     

《地学前缘(英文版)》2023,14(2):101522

The Durkan Complex is a tectonic element of the Makran Accretionary Prism (SE Iran) that includes fragments of Late Cretaceous seamounts. In this paper, the results of map- to micro-scale structural studies of the western Durkan Complex are presented with the aim to describe its structural and tectono-metamorphic evolution. The Durkan Complex consists of several tectonic units bordered by mainly NNW-striking thrusts. Three main deformation phases (D₁, D₂, and D₃) are distinguished and likely occurred from the Late Cretaceous to the Miocene–Pliocene. D₁ is characterized by sub-isoclinal to close and W-verging folds associated with an axial plane foliation and shear zone along the fold limbs. This phase records the accretion of fragments of the seamount within the Makran at blueschist facies metamorphic conditions (160–300 °C and 0.6 – 1.2 GPa). D₂ is characterized by open to close folds with sub-horizontal axial plane that likely developed during the exhumation of previously accreted seamount fragments. An upper Paleocene – Eocene siliciclastic succession unconformably sealed the D₁ and D₂ structures and is, in turn, deformed by W-verging thrust faults typical of D₃. The latter likely testifies for a Miocene – Pliocene tectonic reworking of the accreted seamount fragments with the activation of out of sequence thrusts. Our results shed light on the mechanism of accretion of seamount materials in the accretionary prisms, suggesting that seamount slope successions favour the localization and propagation of the basal décollement. This study further confirms that the physiography of the subducting plates plays a significant role in the tectonic evolution of the subduction complexes.  相似文献   

全球锑原材料贸易格局演化分析     

王春辉  王安建  孙旭 《地球学报》2023,44(2):378-386

随着中国锑矿产量下降以及全球新能源领域对锑需求量的增加, 全球锑原材料供需格局正在改变。对全球锑原材料贸易格局的现状及演化过程开展分析, 有助于世界各国构建弹性的锑原材料供应链。本文基于物质流与复杂网络分析方法, 定量刻画了四类锑原材料(锑矿石、锑金属、锑初级加工品、再生锑)的全球贸易格局(2002—2020年), 分析了典型国家(地区)的锑原材料贸易结构及贸易地位变化特征, 总结了贸易格局的演化规律。研究发现: (1)锑初级加工品是全球最主要的贸易品种, 其贸易量占全球锑原材料总贸易量的一半以上; (2)中国和美国分别是贸易地位排名前两位的国家, 印度、欧盟、韩国是贸易地位上升最快三个国家(地区); (3)欧盟锑金属的进口来源呈现明显的多元化趋势, 显著降低了对中国的进口依赖, 表明欧盟近些年实施的关键原材料多元化进口战略取得了显著成效; (4)中国在全球锑原材料供应格局中的绝对优势地位在下降, 与此同时, 全球锑原材料贸易格局正朝着更加多元的方向发展。  相似文献