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1.
对可用于复合系统协调管理建模的方法作了分析,并以区域经济,资源,环境协调发展问题为背景,探讨了一种基于“流”的复合系统协调管理模型的建模及协调控制方法,并就一简单的经济-资源-环境复合系统,建立了基于“流”的协调管理模型。  相似文献   

2.
复合系统整体协调度模型研究   总被引:24,自引:0,他引:24  
分析了复合系统协调的协同学特征,研究了复合系统复合因子,协调度等概念,在此基础上建立了一类可以实际计算的复合系统整体协调度模型。  相似文献   

3.
基于系统论的复合系统理论,结合系统协调度的本质意义,构建了城市交通-土地利用复合系统的距离协调度模型,并依此提出一种定量评价城市交通与土地利用系统协调度的新方法。本文通过对南京都市区进行实证分析,得出南京市城市交通与土地利用复合系统协调度呈凸曲线发展趋势。  相似文献   

4.
科技—经济系统协调模型研究   总被引:21,自引:0,他引:21  
本文以科技-经济系统为研究对象,研究其协调度的定量分析方法,建立了科技-经济系统协调度模型,应用此模型分析了某市科技-经济系统协调发展现状及趋势。  相似文献   

5.
在构建乡村"三生"复合系统耦合协调评价指标体系的基础上,运用改进的熵值法与耦合协调测度模型,测算了西南地区2005—2016年乡村"三生"复合系统及子系统两两间的耦合协调度,并对其演化状态进行比较与分析.结果表明,西南地区乡村"三生"复合系统耦合协调时间序列表现为失调衰退、过渡发展和协调发展3种演化类型,经历了极度失调、严重失调、中度失调、轻度失调、濒临失调、勉强协调、初级协调和中级协调8种演化状态;空间秩序呈现"极度失调均衡,严重失调与中度失调聚集,初级协调与中级协调交错"的格局演化特征.省级单元乡村"三生"复合系统耦合协调异质性较显著,子系统两两间的耦合协调发展不均衡,生活-生态系统耦合协调水平相对滞后.  相似文献   

6.
区域高等教育-经济发展复合系统协调性研究   总被引:1,自引:0,他引:1  
高等教育-经济发展复合系统的协调运行已成为研究的热点,但缺乏相应的定量研究。运用系统科学理论,提出高等教育-经济发展系统协调的实质是充分利用和促进其间的积极关系,并建立了协调度模型。对1990-2003年江苏省高等教育-经济发展系统协调度进行实证分析,结果表明这一时期复合系统发展分为3个阶段:1991-1994年的无序化、1995-1998年的有序化慢速发展、1999年后的有序化快速发展,说明自1995年以来江苏省率先实施的高等教育扩张政策,与区域经济发展要求相一致,复合系统运行的协调度在不断提高。  相似文献   

7.
论文针对供应链金融信息生态系统四元主体协调度评价展开研究,通过构建供应链金融信息生态系统四元结构模型和复合系统协调度评价模型和实例分析对其进行系统展开研究,为全面认识供应链金融信息生态系统四元主体协调度作出努力。  相似文献   

8.
在构建乡村生产-生活-生态复合系统耦合协调评价指标体系的基础上,运用嫡值法和耦合协调测度模型,测算安徽省16个地级市2010—2019年乡村“三生”复合系统的耦合协调度,并对其时空特征与演化状态进行比较和分析。结果表明:安徽省16个地级市的乡村生产-生活-生态系统综合发展水平整体上均呈波动上升趋势;乡村“三生”复合系统耦合协调水平呈现中度失调、轻度失调、濒临失调、勉强协调,初级协调、中级协调、良好协调7种演化状态,总体经过了升—降—升的过程,大多数城市在10年间均有不同程度的上升,且乡村“三生”复合功能耦合协调演化地域异质性较为明显。  相似文献   

9.
在阐述环境经济协调度概念的基础上,针对辽宁省的具体情况,构建了环境系统与经济系统发展指标体系,运用系统论理论,建立了环境与经济协调度模型,计算出环境系统、经济系统以及环境经济复合系统的协调度,并进行了评价.发现辽宁经济与环境系统之间不协调,经济发展是以牺牲环境为代价的,环境也会进一步制约经济的发展,需要进一步加大环保力度,发展循环经济、实施清洁生产.  相似文献   

10.
在阐述环境经济协调度概念的基础上,针对辽宁省的具体情况,构建了环境系统与经济系统发展指标体系,运用系统论理论,建立了环境与经济协调度模型,计算出环境系统、经济系统以及环境经济复合系统的协调度,并进行了评价。发现辽宁经济与环境系统之间不协调,经济发展是以牺牲环境为代价的,环境也会进一步制约经济的发展,需要进一步加大环保力度,发展循环经济、实施清洁生产。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

17.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

18.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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