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Diagnostic model construction and example analysis of habitat degradation in enclosed bay: II. spatiotemporal variations in habitat degradation in Sansha Bay 被引量:2
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作者 于格 孙芃 +3 位作者 刘光兴 徐东晖 丁光茂 黄东仁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期636-644,共9页
The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habi... The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources. 展开更多
关键词 enclosed bay habitat degradation diagnostic analysis Sansha Bay spatiotemporal variations
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Diagnostic model construction and example analysis of habitat degradation in enclosed bay: I. diagnostic model construction
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作者 于格 孙芃 +3 位作者 刘光兴 徐东晖 丁光茂 黄东仁 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期626-635,共10页
Presently, research is lacking regarding the diagnosis and evaluation of habitat degradation in enclosed bay systems. We established a diagnostic model for enclosed bay habitat degradation(EBHD model) using a multi-ap... Presently, research is lacking regarding the diagnosis and evaluation of habitat degradation in enclosed bay systems. We established a diagnostic model for enclosed bay habitat degradation(EBHD model) using a multi-approach integrated diagnostic method in consideration of driving force-pressurestate-infl uence-response. The model optimizes the indicator standardization with annual average change rate of habitat degradation as the basic element, to refl ect accurately the impact of the change and speed of degradation on the diagnostic results, to quantify reasonably the contribution of individual diagnostic indicator to habitat degradation, and to solve the issue regarding the infl uence of subjective factors on the evaluation results during indicator scoring. We then applied the EBHD model for the Sansha Bay in Fujian Province, China, evaluated comprehensively the situation of habitat degradation in the bay, and screened out the major controlling factors in the study area. Results show that the diagnostic results are consistent in overall with the real situation of the study area. Therefore, the EBHD model is advantageous in terms of objectivity and accuracy, making a breakthrough in diagnosis and evaluation for habitat degradation in enclosed bay systems. 展开更多
关键词 enclosed bay habitat degradation diagnostic model Sansha Bay
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Comparison on construction of strut-and-tie models for reinforced concrete deep beams 被引量:2
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作者 仇一颗 刘霞 《Journal of Central South University》 SCIE EI CAS 2011年第5期1685-1692,共8页
With consideration of the differences between concrete and steel,three solutions using genetic evolutionary structural optimization algorithm were presented to automatically develop optimal strut-and-tie model for dee... With consideration of the differences between concrete and steel,three solutions using genetic evolutionary structural optimization algorithm were presented to automatically develop optimal strut-and-tie model for deep beams.In the finite element analysis of the first method,the concrete and steel rebar are modeled by a plane element and a bar element,respectively.In the second method,the concrete and steel are assigned to two different plane elements,whereas in the third method only one kind of plane element is used with no consideration of the differences of the two materials.A simply supported beam under two point loads was presented as an example to verify the validity of the three proposed methods.The results indicates that all the three methods can generate optimal strut-and-tie models and the third algorithm has powerful capability in searching more optimal results with less computational effort.The effectiveness of the proposed algorithm III has also been demonstrated by other two examples. 展开更多
关键词 reinforced concrete deep beam topology optimization strut-and-tie model genetic evolutionary structural optimization
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Reconstructing Spatial Distribution of Historical Cropland in China′s Traditional Cultivated Region: Methods and Case Study 被引量:4
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作者 YANG Xuhong GUO Beibei +2 位作者 JIN Xiaobin LONG Ying ZHOU Yinkang 《Chinese Geographical Science》 SCIE CSCD 2015年第5期629-643,共15页
As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ... As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ′top-down′ decision-making behaviors, here are two global historical land-use datasets, generally referred as the Sustainability and the Global Environment datasets(SAGE datasets) and History Database of the Global Environment datasets(HYDE datasets). However, at the regional level, these global datasets have coarse resolutions and inevitable errors. Considering various factors that influenced cropland distribution, including cropland connectivity and the limitation of natural and human factors, this study developed a reconstruction model of historical cropland based on constrained Cellular Automaton(CA) of ′bottom-up′. Then, an available labor force index is used as a proxy for the amount of cropland to inspect and calibrate these spatial patterns. Applied the reconstruction model to Shandong Province, we reconstructed its spatial distribution of cropland during 8 periods. The reconstructed results show that: 1) it is properly suitable for constrained CA to simulate and reconstruct the spatial distribution of cropland in traditional cultivated region of China; 2) compared with ′SAGE datasets′ and ′HYDE datasets′, this study have formed higher-resolution Boolean spatial distribution datasets of historical cropland with a more definitive concept of spatial pattern in terms of fractional format. 展开更多
关键词 traditional cultivated region historical cropland reconstruction constrained Cellular Automaton (CA) Shandong Province
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On Constructing the Cognitive Model of Knowledge Acquisition in Globalization-Oriented Study
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作者 ZHANG Jin-bao 《Sino-US English Teaching》 2013年第7期517-523,共7页
This paper which is directed to constructing the cognitive model of knowledge acquisition in view of the increasing need of globalization-oriented study, points out features of globalization-oriented study, and propos... This paper which is directed to constructing the cognitive model of knowledge acquisition in view of the increasing need of globalization-oriented study, points out features of globalization-oriented study, and proposes the importance and necessity for constructing the CMKAGS (cognitive model of knowledge acquisition in globalization-oriented study) which includes attention, background knowledge, and chunking memory that involves semantic chunking, information encoding as well as choice of information encoding. The cognitive model of knowledge acquisition in question aims at helping e-learners to memorize their learned knowledge and improve their studies effectively and efficiently, whether they study in enhanced conditions or in natural conditions 展开更多
关键词 globalization-oriented study cognitive psychology background knowledge cognitive model ofknowledge acquisition memory
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Research on the Multidimensional Constraint Stability of Bridge Structure Modeling based on Optimization Model
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作者 Cheng kang 《International Journal of Technology Management》 2016年第9期35-37,共3页
In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web str... In this paper, we conduct research on the multidimensional constraint stability of bridge structure modeling based on the optimization model. The current internal and the external research results to the truss web structure, the high internode the aspect ratio and the stiffness of the middle truss brace of the truss web, deffection of composite beams of the impact of stress is a very important problem in the design of the bridge. Structural health monitoring is the use of the field of the non-destructive sensing technology, including the structural response, including structural system characteristics analysis, to achieve the purpose of monitoring structural damage or degradation. Under this basis, this paper proposes the new idea on the modelling and simulates the performance. 展开更多
关键词 MULTIDIMENSIONAL Constraint Stability Bridge Structure Optimization Model.
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改革开放四十年电影融资模式流变 被引量:3
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作者 陶冶 《当代电影》 CSSCI 北大核心 2018年第6期14-19,共6页
改革开放四十年的中国电影史某种程度上亦是一部电影金融的历史,本文聚焦中国电影四十年的融资模式问题,站在金融史的视角重新审视这段历程,并对每一阶段的主要融资模式提出了模型化的建构,计划经济体系下财政拨付的"无忧"融... 改革开放四十年的中国电影史某种程度上亦是一部电影金融的历史,本文聚焦中国电影四十年的融资模式问题,站在金融史的视角重新审视这段历程,并对每一阶段的主要融资模式提出了模型化的建构,计划经济体系下财政拨付的"无忧"融资模型为第五代的横空出世提供了当时全世界最好的金融保障;市场化初期经历了"合拍融资模式"与"预售融资模型"的过渡,直到21世纪初实现与好莱坞同步的股本结构合理化的"拼盘融资模型";然而在2015年后,随着互联网金融对电影领域的深度介入,产生了以BAT为代表的"全产业链融资模型"和快鹿那样将电影项目作为"标的"的P2P融资模型;最后,我们假设以"创业融资模型"在电影项目中的应用来展望未来,前景不容乐观。 展开更多
关键词 改革开放四十年 电影融资 模式 模型化建构
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Reducing the climate shift in a new coupled model
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作者 Yanli Tang Lijuan Li +1 位作者 Wenjie Dong Bin Wang 《Science Bulletin》 SCIE EI CAS CSCD 2016年第6期488-494,共7页
Climate drift refers to spurious long-term changes that may be inherent in coupled models when external forcing factors are fixed. Understanding the sources of this drift and tuning the drift are crucial for obtaining... Climate drift refers to spurious long-term changes that may be inherent in coupled models when external forcing factors are fixed. Understanding the sources of this drift and tuning the drift are crucial for obtaining reasonable simulations from coupled models. To prepare for the upcoming Coupled Model Intercomparison Project Phase 6, a new coupled model has been constructed based on the Community Earth System Model and the Grid-point Atmospheric Model of IAP LASG version 2. However, the surface temperature predicted by the new model is too underestimated, and this underestimation is caused by a type of climate drift, i.e., ‘‘initial shock.'' This study analyzes the source of the cold surface temperature from the perspective of energy balance and attempts to reduce the surface temperature drift by tuning the relative humidity threshold for low cloud. 展开更多
关键词 Climate drift CESM–GAMIL2 Initial shock Relative humidity threshold
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