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1.
中华人民共和国人口电子地图集系统设计   总被引:1,自引:0,他引:1  
“中华人民共和国人口电子地图集”是我国最新的第五次人口普查数据的集成,是以地图、文字、数字、图表等多种信息表达手段,全面反映了中国人口发展基本现状和趋势的科学参考图集。它可以实现对人口数据的输入/输出、分类、存储、查询、统计、制图、分析和管理,提供给决策者和研究者分析人口问题和制定人口政策的辅助工具。本文详细介绍了图集的系统总体设计、主要功能模块设计、内容组成等。在总体设计上,提出了以电子地图制作子系统、图集管理与集成子系统、图集浏览查询子系统和人口数据查询子系统为四大主要部分的系统结构,并进而对系统中的主要模块进行了介绍.如专题制图符号模型、数据库的目录树管理、电子地图集的管理与集成,通过这些模块,分析了系统的运行机制和流程;在图集内容上,在分析“五普”数据和我国人口实际国情的基础上,选取涉及十项主题(环境、人口分布、性别与年龄、人口变动、民族、家庭婚姻、生育、教育、就业、住房)近200幅地图组成图集的内容,反映我国人口的基本现状、动态变化、地域分布、结构构成等;最后,给出了使用不同制图符号建立的人口地图实例,可以直观地反映各项人口指标的区域差异和变化规律。  相似文献   

2.
多粒度时空对象的行为特征是描述全空间信息系统中不同对象之间控制与响应的重要方面,是体现时空实体相互作用、动态变化、多能自主的核心,是全空间信息系统作为一个"活"的信息系统的亮点所在。本文面向全空间信息系统,对多粒度时空对象行为的基本概念、触发方式、分类方式、描述框架进行了阐述,在此基础上,提出了多粒度时空对象行为特征的总体形式化描述方法,并分别从行为能力、环境影响因素、行为触发条件、行为作用对象和行为计算模型5个方面对对象的行为特征进行详细描述,为全空间场景中多粒度时空对象的行为建模提供了基本思路。  相似文献   

3.
中国省级行政区边界形状的GIS分析   总被引:1,自引:0,他引:1  
本文借助GIS软件支持,计算了我国32个省的平面轮廓形状的分维、形状指数和紧凑度。结果表明,形状复杂(边缘复杂程度高,破碎度较大)的省(区)主要集中在东部及沿海地区;形状较紧凑的省(区)主要集中在西部地区,东部省与西部省的形状特征有较大差异。另探讨了各地区的地理气候环境和历史人文特征所致的主要原因,并初步分析了各特征对交通等组织的影响。  相似文献   

4.
多粒度时空对象关联关系描述现实世界客观实体之间存在的各种关系及其相互影响,是对实体间关联、作用关系的表达,按照其描述主体的不同主要分为时间关联关系、空间关联关系、属性关联关系和综合关联关系。本文从全空间信息系统的背景出发,对多粒度时空对象关联关系的基本概念进行了阐述,明确了其形式化表达方式和分类。在此基础上,对关联关系的构建和管理进行阐述和分析,说明了静态构建方式和动态构建方式的适用场景。关联关系通过约束作用和行为传导机制来维持数据世界的一致性和联动,本文最后对关联关系的约束类型及其定义和关系-行为传导机制进行了简要说明。  相似文献   

5.
With the astounding development and gradual improvement of remote sensing technology, as an advancedscience technology, it is used to provide multi-temporal, large scope real-time information for land-use dynamic change,and also is one of the best efficient methods for studying the earth resources and environment. Remote sensing image hasits characteristics of ample information and reflecting the objective realities. The paper uses multi-temporal TM images in1986, 1996 and 2000, and relevant statistic data to analyze land-use changes of Dalian City in Liaoning Province of Chi-na over ten years by means of the correlation analysis method. The results have shown that two methods could con-formably reflect the present land-use change. Urbanization is closely correlative to natural factors and economic develop-ment. Especially in recent 20 years, under the influence of the reform and open-up policy, Dalian, as a specific coastcity, is becoming an international metropolis.  相似文献   

6.
Quality of life(QOL) is a hotspot issue that has attracted increasing attention from the Chinese Government and scholars, it is also a vital issue that should be addressed during the cause of ′establishing overall well-off society′. Northeast China is one of the most import old industrial bases in China, however, the industrial structure of heavy chemical industry and the development mode of ′production first, living last′ have leaded to series of social problems, which have also become a serious bottleneck to social stability and economic sustainable development. Through applying the methods of BP neural network, exploratory spatial data analysis(ESDA) and spatial regression model, this paper examines the space-time dynamics of QOL of the residents in Northeast China. We first investigate the indexes of QOL of the residents and then use ESDA methods to visualize its space-time relationship. We have found a spatial agglomeration of QOL of the residents in middle-southern Liaoning Province, central Jilin Province and Harbin-Qiqihar-Daqing area of Heilongjiang Province. Two third of the counties are low-low spatial correlation, and the correlative type of about 60% of the prefecture level areas keeps stable, indicating QOL of the residents in Northeast China shows a certain character of path dependence or spatial locked. We have also found that economic strength and development levels of service industry have positive and obvious effect on QOL of the residents, while the effect of such indexes as the social service level and the proportion of the tertiary industries are less.  相似文献   

7.
红鳍笛鲷弧菌病病原的研究   总被引:7,自引:0,他引:7  
从广东湛江特呈岛鱼排取患病红鳍笛鲷进行病原分离、纯化,得到一株病原菌Ls 1。该菌 为革兰阴性短杆菌,有运动性,菌落半透明,最适温度28~30℃,需盐生长,氧化酶反应阳性,发酵 葡萄糖不产气,不发酵肌醇,对弧菌抑制剂O/129敏感。经API ID32E细菌鉴定系统及弧菌科细 菌生化鉴定管鉴定,该菌为一株溶藻弧菌(Vibrioaginolyticus);其对红鳍笛鲷的半数致死量为6.32 ×105mL-1。药敏试验结果表明,该菌对阿莫西林、先锋V不敏感,对新生霉素、卡那霉素、多粘菌 素B、四环素中度敏感,而对庆大霉素、氟哌酸、氯霉素、红霉素、链霉素和复方新诺明等有较高的敏 感性。  相似文献   

8.
五种鲤科鱼类生长激素cDNA的克隆和序列分析   总被引:1,自引:0,他引:1  
通过RT-PCR方法,以草鱼、鳙鱼、鲫鱼、鲤鱼、齐口裂腹鱼等5种鲤科重要经济鱼类的垂体总RNA为模板扩增出其生长激素(fish growth hormone,fGH)的完整ORF序列,并克隆到pMD18-T载体上,命名为pMD-1(草鱼)、pMD-2(鳙鱼)、pMD-3(鲫鱼)、pMD-4(鲤鱼)、pMD-5(齐口裂腹鱼)。测序结果显示,ORF序列其长度均为633 bp。序列分析表明,所有ORF序列均以ATG为起始密码,以TAG为终止密码,编码210个氨基酸残基,推导的生长激素前体由22个氨基酸的信号肽和188个氨基酸的成熟肽组成。同源性分析表明,草鱼、鳙鱼、鲤鱼、鲫鱼和齐口裂腹鱼的fGH同源性在93.3%~99.5%之间。  相似文献   

9.
以库仑破裂应力变化计算为基础,研究断层的相互作用。从震源断层和投影断层两个角度出发,研究5种地震断层模型分别描述地震断层和投影断层时库仑破裂应力变化的分布特征,分析震源断层以及投影断层的不同滑动机制对库仑破裂应力变化分布的影响。分析发现,断层的相互作用与断层的滑动机制关系密切;走滑断层还与其左右旋有一定关系;除斜滑断层外,其他断层之间的相互作用呈现一定的对称关系。  相似文献   

10.
Oceanic uptake of anthropogenic carbon dioxide results in a decrease in seawater pH, a process known as "ocean acidification". The pearl oyster Pinctada fucata, the noble scallop Chlamys nobilis, and the green-lipped mussel Perna viridis are species of economic and ecological importance along the southern coast of China. We evaluated the effects of seawater acidification on clearance, respiration, and excretion rates in these three species. The animals were reared in seawater at pH 8.1 (control), 7.7, or 7.4. The clearance rate was highest at pH 7.7 for P. fucata and at pH 8.1 for C. nobilis and P. viridis. The pH had little effecton the respiration rate of P. fucata and P. viridis. In contrast, the respiration rate was significantly lower atpH 7.4 in C. nobilis. The excretion rate was significantly lower at pH 7.4 than pH 8.1 for all species. Theresults indicate that the reduction in seawater pH likely affected the metabolic process (food intake, oxygenconsumption, and ammonia excretion) of these bivalves. Different species respond differently to seawateracidification. Further studies are needed to demonstrate the exact mechanisms for this effect and evaluateadaptability of these bivalves to future acidified oceans.  相似文献   

11.
The Chinese “Yangtze” alligator is a rare reptile that has been listed as an “endangered species” by the United Nations, so its preservation has become an urgent task. A study of its habitats through analysis of their Landsat images will provide a scientific basis for the government departments concerned to select the best locations for its breeding. The Chinese alligator is a subtropical reptile of freshwater rivers, lakes and ponds. Found only in China, it is now distributed only in the border region between the three provinces of Anhui, Zhejiang and Jiangsu. On the basis of previous investigations by Chinese scientists, and from an analysis and interpretation of their Landsat images, we made a special study, review, and classification of the natural environment of the alligator’s present habitats (and the modern changes in the natural background of these hatitats) so that the government departments concerned with the preservation of the reptiles may have a scientific basis for determining the best locations for the breeding and propagation of the alligator. This paper was published in Chinese inOcean. Linn. Sin. 16(1): 35–41, 1985.  相似文献   

12.
皮质衣服作为服饰的一种,与人类社会发展及文化变迁关系极其密切。诞生初始,皮衣以实用功能为主,但已有原始人类审美意识的萌芽。后来与封建礼制和封建特权结合起来,负有浓厚的政治权势色彩,成为特权阶级的享用品,功利性明显地渗透于审美意趣之中。在商品经济的现代社会,皮衣又成为时尚和消费的符号,呈现出审美和文化的多元化特点。  相似文献   

13.
The liquid state, especially water, has long been regarded as the most formidable problem in the field of statistical mechanics. The coefficient of viscosity of water is calculated using a simplified model based on the microstructure of water and methods similar to that used by Rice et al. (1961) who studied the non-equilibrium statistical mechanics of simple liquids, such as liquid argon. derived From the Liouville equation. This work's singlet and doublet equations are somewhat different From those derived by Rice et al. (1961) and solutions were obtained by the perturbation method. The calculated coefficient of viscosity of water at different temperature. using this method agree well with standard values.  相似文献   

14.
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??API?????T3?????????????????м????????????????У????????顢???????????????????????????顢???????????????????顢?????λ??????????鼰??????????????????????,????????????????????в?????????????????????У?????????????????????λ??????????????????????????;???????????????????λ??????????????????????????????к???????????  相似文献   

15.
几种因子对鞍带石斑鱼精子活力的影响   总被引:3,自引:0,他引:3  
研究不同梯度的盐度、pH、温度及低温保存时间对鞍带石斑鱼精子活力的影响。结果表明:鞍带石斑鱼精子活力的适宜盐度范围为27.5~35.0,最适盐度为32.5,此时精子的快速运动时间和寿命分别为13.2min和14.8min;最适pH为8.5,精子的快速运动时间及寿命最长,分别达12.7min和17.3min;温度范围为27~31℃,以29℃时快速运动时间最长,达16.6min;在0~4℃冰箱保存6h后鞍带石斑鱼精子活力未显著降低,其中保存前精子快速运动时间为18.4min,保存6h后为18.2min,保存120h后仍有活力,精子快速运动时间为2.3min,精子激活率为3.3%。以x为保存时间,快速运动时间y和寿命y′符合线性方程y=-0.8334x+19.164(R2=0.9856),y′=-1.1358x+27.8(R2=0.9573)。  相似文献   

16.
全空间地理信息系统的建设和智慧城市等GIS应用的发展,需对各类地理实体或地理现象抽象成的时空对象采集多类型的属性数据,这些属性数据一般具有多尺度、多维度、动态性的特点,带给时空对象属性特征的表达和管理一定的挑战。本文针对当前时空对象属性特征表达方法中存在的组织结构不清晰、存储冗余、语义异构等表达问题,提出了一套顾及语义尺度和动态特性的属性特征的表达和操作方法。该方法基于概念分类理论实现时空对象属性信息的分类组织,在属性特征表达中引入独立于时空对象空间特征的时间标记,结合属性表达的原始集族和更新集族来记录和管理不同时间节点下的时空对象属性特征;进而面向具有不同语义尺度表达需求的属性特征,设置知识参考表达集合,并在属性特征表达中增加语义尺度标识,对其语义尺度及不同语义尺度间的转换关系进行描述。最后,基于独立时间标记、知识参照表达集合及语义尺度标识,给出属性信息表达在时间尺度转换和语义尺度转化的操作方法,并举例给出了该属性特征动态表达和操作方法的一种实现。本文提出的方法有助于减少时空对象数据模型的存储冗余,提高其属性信息的操作效率,初步实现了时空对象属性特征的多时间尺度和多语义尺度的认知方式,为时空对象属性特征的精细化管理提供了新思路。  相似文献   

17.
企业管理者存在着管理动力不足和淘空企业的现象,这在很大程度上是内部控制环境出了问题.文章提出了优化董事会决策机制,理顺董事会与经理层关系;完善企业内部监控体系和信息系统;构建合理的管理组织架构;营造良好的企业文化以增强员工的素质等内部控制环境建设的基本思路.  相似文献   

18.
地理对象之间的关联关系是地理对象之间的相互作用形式。任何地理对象都不是独立存在的,与其他的地理对象有一定的关联关系,并且这些关联关系是复杂多样的。地理场景就是在地理对象之间普遍存在的、复杂多样的关联作用下形成的一个统一的整体。传统GIS数据模型对地理对象之间关联关系的描述多侧重于空间关系,其他的关联关系往往需要经过比较复杂的计算和推理后求得,难以完整地表达地理对象之间复杂的相互作用关系,不完全符合人类对地理现象的认知情况。然而,在全空间系统中,可以根据常见的地理分析需求对多粒度时空对象间关联、作用关系进行分类表达,便于客观实体全方位的抽象与表达。对象间的关联关系可主要分为空间关系、时间关系、属性关系、因果关系、认知关系5大类。本文用地理实体作为案例,分析了关联关系的表达模型。  相似文献   

19.
Actinomycetes population from continental slope sediment of the Bay of Bengal was studied. Samples were collected during two voyages of FORV Sagar Sampada in 2004 (May-June) and 2005 (July) respectively from 11 transects (each transect had ca. 200 m, 500 m, and 1 000 m depth stations). The physicochemical parameters of overlying water, and sediment samples were also recorded. The actinomycete population ranged from 5.17 to 51.94 CFU/g dry sediment weight and 9.38 to 45.22 CFU/g dry sediment weight during the two cruises respectively. No actinomycete colony was isolated from stations in 1 000 m depth. Two-way analysis of variance showed significant variation among stations (ANOVA two-way, P〈0.05), but no significance was found between the two cruises (ANOVA two-way, P〈0.05). Populations in stations in 500 m depth in both cruises were higher than that of 200 m depth stations with statistically insignificant difference (ANOVA two-way, P〉0.05). Three actinomycetes genera were identified. Streptomyces was found to be the dominating one in both the cruises, followed by Micromonospora, and Actinomyces. The spore of Streptomyces isolates showed the abundance in spiral spore chain. Spore surface was smooth. Multiple regression analysis revealed that the influencing physico-chemical factors were sediment pH, sediment temperature, TOC, porosity, salinity, and pressure. The media used in the present study was prepared with seawater. Thus, they may represent an autochthonous marine flora and deny the theory of land runoff carriage into the sea for adaptation to the salinity of the seawater and sediments.  相似文献   

20.
通过对雷州半岛蔗区甘蔗营养状况的普查 ,利用数理统计方法 ,分析了养分间、养分与经济性状间的相关关系。结果表明 :增N、提高土壤pH值可显著提高茎长 ,茎长的提高可促进单茎重、工业蔗产量、含糖量极显著提高。增K、Mg可显著提高有效茎 ,有效茎的提高可促进工业蔗产量显著提高 ,却导致锤度显著下降。偏施Mg会导致锤度极显著下降。因而采取的措施为增N、K ,合理配施镁含量低的石灰和P肥 ,以促进茎长、单茎重、有效茎的提高 ,从而提高产量 ;控施Mg肥 ,达到提高糖分含量的目的  相似文献   

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