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校本课程开发的“环境模式”剖析——以太仓市部分小学校本课程开发为例 被引量:1
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作者 朱强 《江苏教育研究》 2003年第6期58-61,共4页
关键词 校本课程开发 太仓市 小学 课程改革 课程资源 “环境模式”
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浅谈“环境”领导模式
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作者 李洪群 郭燕 蔡迎莺 《山东电力高等专科学校学报》 2002年第1期8-10,共3页
论文通过实际分析与理论探讨 ,分析了市场经济条件下企业对基于创造环境的领导行为的需求 ,并提供了三种可借鉴的领导方式。
关键词 “环境”领导模式 企业领导 市场经济 计划经济 古典经济理论
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体育校本课程开发的思想基础 被引量:13
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作者 董翠香 李兴艳 王珊 《上海体育学院学报》 CSSCI 北大核心 2007年第5期91-94,共4页
基于国家课程开发模式与各个学校多样性和学生差异性之间的矛盾,阐述体育校本课程开发的思想基础:"实践模式"、"过程模式"与"环境模式"。分析三种模式的主体思想及其对我国体育校本课程开发的借鉴意义。... 基于国家课程开发模式与各个学校多样性和学生差异性之间的矛盾,阐述体育校本课程开发的思想基础:"实践模式"、"过程模式"与"环境模式"。分析三种模式的主体思想及其对我国体育校本课程开发的借鉴意义。认为:应根据文化背景,合理借鉴此三种课程开发模式的积极思想,开发各具特色的体育校本课程。 展开更多
关键词 体育校本课程 开发 “实践模式” “过程模式” “环境模式”
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信息化教育中的“媒体等同”现象探析 被引量:2
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作者 滕芳 石明虹 《电化教育研究》 CSSCI 北大核心 2006年第6期15-18,共4页
在各种媒体介质应用日益丰富的信息化教育中,“媒体等同”现象十分突出。本文在探究“媒体等同”概念体系的基础上,分析了信息化教育中的“媒体等同”现象,即虚拟教育环境体验和现实教育环境体验等同以及不同教学媒体的传播效果等同,并... 在各种媒体介质应用日益丰富的信息化教育中,“媒体等同”现象十分突出。本文在探究“媒体等同”概念体系的基础上,分析了信息化教育中的“媒体等同”现象,即虚拟教育环境体验和现实教育环境体验等同以及不同教学媒体的传播效果等同,并指出“媒体等同”使得教育信息化的学习模式从“工具—任务”模式转变为“环境—认知”模式,从而为充分利用各种教育媒体,提高学习者的学习积极性、教学效果和教学效率指明了新的途径。 展开更多
关键词 媒体等同 信息化教育 “工具-任务”模式 “环境-认知”模式 教学效率 学习积极性 教育环境
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ANALYSIS OF HABITAT PATTERN CHANGE OF RED-CROWNED CRANES IN THE LIAO HE DELTA USING SPATIAL DIVERSITY INDEX 被引量:3
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作者 WANGLing LIXiu-zhen +1 位作者 HUYuan-man GUODu-fa 《Chinese Geographical Science》 SCIE CSCD 2003年第2期164-170,共7页
Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. Th... Habitat pattern change of red-crowned cranes (Grus japonensis) in t he Liaohe Delta between 1988 and 1998 was analyzed with the help of Spatial Dive rsity Index based on remote sensing data and field investigation. The result sho wed that the influence from human activities on the wetland habitat of red-crow ned cranes was prominent with the development of oil and agricultural exploitati on, and the habitat pattern of red-crowned cranes had been obviously changed by the human disturbance during the ten years. The areas with high Spatial Diversi ty values (SD≥0.65) and that with mid-high values (0.5≤SD< 0.65), which const ituted the main part of suitable habitat of red-crowned cranes,had reduced to 9142ha and 5576ha respectively, with the shrinking of natural land cover, such a s reed and Suaeda community. The habitat pattern became more fragmented, which w as caused by roads and wells during oil exploration. It was indicated that the s uitability and quality of habitat for red-crowned cranes in the Liaohe Delta we re degraded in the last decade. The results also showed that diversity index cou ld reflect the habitat suitability of red-crowned cranes quantitatively and des cribe the spatial pattern of the habitat explicitly. This study will provide a s cientific basis for habitat protection of red-crowned cranes and other rare spe cies in wetlands. 展开更多
关键词 spatial diversity Index red-crowned crane ( GrUS japonensis) habitatpattern the liaohe delta
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Dynamic Assessment on Regional Eco-environmental Quality Using AHP-Statistics Model—A Case Study of Chaohu Lake Basin 被引量:8
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作者 LI Ruzhong 《Chinese Geographical Science》 SCIE CSCD 2007年第4期341-348,共8页
An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessmen... An indicator system closely connected with eco-environment, in which indicator involves in such fields as society, economy, resources, environment and ecology, is first proposed for eco-environmental quality assessment. Then, a hierarchical model with four levels is established by virtue of these indicators and attributes. In the model, weights of indicators and attributes are determined by combining Delphi method with the Analytic Hierarchy Process (AHP) and a statistic method is used to eliminate the influences arising from the differences in dimension and magnitude of indicators. On these grounds, an AHP-statistics model is provided for regional eco-environmental quality assessment. As a case, such AHP-statistics model is utilized in the dynamic analysis of regional eco-environmental assessment in Chaohu Lake basin. Study results show that natural environmental quality in the watershed was in the declining state while social environmental quality was in a markedly improved situation from 1996, and the synthetic eco-environmental quality was gradually and slowly improved under the common influences of both natural and social environmental factors. Example of application testified the capacities of above methodology to evaluate the real and dynamic state of regional eco-environmental quality. 展开更多
关键词 eco-environmental quality assessment AHP-statistics model Chaohu Lake
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Strength failure and crack coalescence behavior of sandstone containing single pre-cut fissure under coupled stress, fluid flow and changing chemical environment 被引量:3
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作者 鲁祖德 陈从新 +1 位作者 冯夏庭 张友良 《Journal of Central South University》 SCIE EI CAS 2014年第3期1176-1183,共8页
In order to study the strength failure and crack coalescence characteristics of cracked rocks, uniaxial compression experiments were conducted on cylindrical sandstone specimens, sampled from Longyou Grottoes of Zheji... In order to study the strength failure and crack coalescence characteristics of cracked rocks, uniaxial compression experiments were conducted on cylindrical sandstone specimens, sampled from Longyou Grottoes of Zhejiang Province, China, with a single pre-cut crack soaking in different chemical solutions. Based on the results of uniaxial compressive test under different chemical solutions and velocities of flow, the effect of strength and deformation characteristics and main modes of crack coalescence for cracked rocks under chemical corrosion were analyzed. The results show that the pH value and velocity of the chemical solutions both have great influence on the sandstone sample's uniaxial compressive strength and deformation characteristics. Cracked sandstone samples are tension-destructed under uniaxial compression, and the crack propagation directions are consistent with the loading direction. The phenomena of crack initiation, propagation and coalescence of sandstone are well observed. Four different crack types are identified based on the crack propagation mechanism by analyzing the ultimate failure modes of sandstone containing a single pre-cut fissure. The failure process of specimen in air is similar with the specimen under chemical solutions, however, the initial time of crack occuring in specimen under chemical solutions is generally earlier than that in the natural specimen, and the crack propagation and coalescence process of specimen under chemical solutions are longer than those of the natural specimen due to softening of structure of rock caused by hydro-chemical action. Immersion velocity of flow and chemical solutions does not have influence on the ultimate modes of crack coalescence. 展开更多
关键词 strength and deformation characteristics crack coalescence SANDSTONE single pre-cut fissure chemical environment
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UWB channel modeling for indoor line-of-sight environment 被引量:5
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作者 汪洋 许洪光 +1 位作者 张钦宇 张乃通 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第6期866-870,共5页
SV/IEEE 802.15.3a model has been the standard model for Ultra-wide bandwidth (UWB) indoor non-line-of-sight (NLOS) wireless propagation,but for line-of-sight (LOS) case,it is not well defined. In this paper,a new stat... SV/IEEE 802.15.3a model has been the standard model for Ultra-wide bandwidth (UWB) indoor non-line-of-sight (NLOS) wireless propagation,but for line-of-sight (LOS) case,it is not well defined. In this paper,a new statistical distribution model exclusively used for LOS environment is proposed based on investigation of the experimental data. By reducing the number of the visible random arriving clusters,the model itself and the parameters estimating of the corresponding model are simplified in comparison with SV/IEEE 802.15.3a model. The simulation result indicates that the proposed model is more accurate in modeling small-scale LOS environment than SV/IEEE 802.15.3a model when considering cumulative distribution functions (CDFs) for the three key channel impulse response (CIR) statistics. 展开更多
关键词 UWB LINE-OF-SIGHT indoor propagation channel MULTIPATH statistical model
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Model of wind-generated ambient noise in stratified shallow water 被引量:3
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作者 林建恒 高天赋 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期144-151,共8页
In order to build a rapid ocean ambient noise model adapted for a stratified shallow water, a hybrid model of normal mode method (for far field) and ray method (for near field) is suggested which combines the advantag... In order to build a rapid ocean ambient noise model adapted for a stratified shallow water, a hybrid model of normal mode method (for far field) and ray method (for near field) is suggested which combines the advantages of both methods. Since the near field of wind-generated noise is not sensitive to the sound speed pro- file, the sound speed profile is regarded as a constant; which makes the model rapid and accurate. The simulation results are in agreement with those of the wave model. 展开更多
关键词 wind-generated ambient noise RAY normal mode hybrid model
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Spatial distribution of Cd and Cu in soils in Shenyang Zhangshi Irrigation Area(SZIA),China 被引量:1
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作者 Li-na SUN Xiao-bo YANG +2 位作者 Wen-qing WANG Li MA Su CHEN 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第3期271-278,共8页
Heavy metal contamination of soils,derived from sewage irrigation,mining and inappropriate utilization of various agrochemicals and pesticides,and so on,has been of wide concern in the last several decades.The Shenyan... Heavy metal contamination of soils,derived from sewage irrigation,mining and inappropriate utilization of various agrochemicals and pesticides,and so on,has been of wide concern in the last several decades.The Shenyang Zhangshi Irrigation Area(SZIA) in China is a representative area of heavy metal contamination of soils resulting from sewage irrigation for about 30 years.This study investigated the spatial distribution and temporal variation of soil cadmium(Cd) and copper(Cu) contamination in the SZIA.The soil samples were collected from the SZIA in 1990 and 2004;Cd and Cu in soils was analyzed and then the spatial distribution and temporal variation of Cd and Cu in soils were modeled using Kriging methods.The results show that long-term sewage irrigation had caused serious Cd and Cu contamination in soils.The mean and the maximum of soil Cd are markedly higher than the levels in second grade standard soil(LSGSS) in China,and the maximum of soil Cu is close to the LSGSS in China in 2004 and is more than the LSGSS in China in 1990.The contamination magnitude of soil Cd and the soil extent of Cd contamination had evidently increased since sewage irrigation ceased in 1992.The contamination magnitude of soil Cu and the soil extent of Cu contamination had evidently increased in topsoil,but obviously decresed in subsoil.The soil contamination of Cd and Cu was mainly related to Cd and Cu reactivation of contaminated sediments in Shenyang Xi River and the import of Cd and Cu during irrigation.The eluviation of Cd and Cu in contaminated topsoil with rainfall and irrigation water was another factor of temporal-spatial variability of Cd and Cu contamination in soils. 展开更多
关键词 Cadmium (Cd) Copper (Cu) Contamination of soils Spatial distribution Shenyang Zhangshi Irrigation Area (SZLA)
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A comparison of landscaping plant utilization in some residential quarters in Beijing
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作者 王晓晓 谭峰 《Agricultural Science & Technology》 CAS 2005年第1期24-31,共8页
A dwelling district is the most direct space of people’s living environment. The environmental construction should take the improvement and maintenance of the ecologically balance in housing estate as its aim and the... A dwelling district is the most direct space of people’s living environment. The environmental construction should take the improvement and maintenance of the ecologically balance in housing estate as its aim and the coexistence between man and nature as its goal. By making an analysis of the current situation of afforestation, landscape, functional requirements and humanistic environment of the six residential quarters of Huilongguan Fengyayuan, Sainaweila,Xinxinjiayuan of the Asian Games, and others in Beijing, this paper presents an arrangement mode of plants in dwelling districts. 展开更多
关键词 PLANT LANDSCAPE dwelling district BEIJING
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Hydrodynamic Comparison of a Semi-submersible,TLP,and Spar:Numerical Study in the South China Sea Environment 被引量:5
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作者 Binbin Li Kun Liu +1 位作者 Gongwei Yan Jinping Ou 《Journal of Marine Science and Application》 2011年第3期306-314,共9页
The South China Sea contains tremendous oil and gas resources in deepwater areas. However, one of the keys for deepwater exploration, the investigation of deepwater floating platforms, is very inadequate. In this pape... The South China Sea contains tremendous oil and gas resources in deepwater areas. However, one of the keys for deepwater exploration, the investigation of deepwater floating platforms, is very inadequate. In this paper, the authors studied and compared the hydrodynamics and global motion behaviors of typical deepwater platforms in the South China Sea environment. The hydrodynamic models of three main types of floating platforms, e.g. the Semi-submersible, tension leg platform (TLP), and Truss Spar, which could potentially be utilized in the South China Sea, were established by using the 3-D potential theory. Additionally, some important considerations which significantly influence the hydrodynamics were given. The RAOs in frequency domains as well as global motions in time domains under time-varying wind, random waves, and current in 100-y, 10-y, and 1-y return period environment conditions were predicted, compared, and analyzed. The results indicate that the heave and especially the pitch motion of the TLP are favorable. The heave response of the Truss Spar is perfect and comparable with that of the TLP when the peak period of random waves is low. However, the pitch motion of Truss Spar is extraordinarily lar^er than that of Semi-submersible and TLP. 展开更多
关键词 SEMI-SUBMERSIBLE Spar tension leg platform (TLP) South China Sea HYDRODYNAMICS
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Response of the North Pacific Oscillation to global warming in the models of the Intergovernmental Panel on Climate Change Fourth Assessment Report 被引量:1
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作者 CHEN Zheng GAN Bolan WU Lixin 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期601-611,共11页
Based on 22 of the climate models from phase 3 of the Coupled Model Intercomparison Project, we investigate the ability of the models to reproduce the spatiotemporal features of the wintertime North Pacific Oscillatio... Based on 22 of the climate models from phase 3 of the Coupled Model Intercomparison Project, we investigate the ability of the models to reproduce the spatiotemporal features of the wintertime North Pacific Oscillation(NPO), which is the second most important factor determining the wintertime sea level pressure field in simulations of the pre-industrial control climate, and evaluate the NPO response to the future most reasonable global warming scenario(the A1B scenario). We reveal that while most models simulate the geographic distribution and amplitude of the NPO pattern satisfactorily, only 13 models capture both features well. However, the temporal variability of the simulated NPO could not be significantly correlated with the observations. Further analysis indicates the weakened NPO intensity for a scenario of strong global warming is attributable to the reduced lower-tropospheric baroclinicity at mid-latitudes, which is anticipated to disrupt large-scale and low-frequency atmospheric variability, resulting in the diminished transfer of energy to the NPO, together with its northward shift. 展开更多
关键词 North Pacific Oscillation(NPO) greenhouse gas warming CMIP3 climate models atmospheric baroclinicity climate change empirical orthogonal function
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A study on tourism development model with dynamic mechanism of circular economy 被引量:1
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作者 WU Li-yun DONG Suo-cheng CHEN Fang-ying 《Ecological Economy》 2010年第4期439-446,共8页
With the social and economic development,conflict among the shortage of resources,environmental destruction and economic development is ever more pronounced.In this context,the circular economy was gradually accepted.... With the social and economic development,conflict among the shortage of resources,environmental destruction and economic development is ever more pronounced.In this context,the circular economy was gradually accepted.Guided by sustainable development concept and promoted by six external forces,tourism circular economy take tourism micro-cycle model as the core,implement in corporate and social levels,improve resource utilization efficiency,reduce tourism's adverse impacts on the surrounding environment through recycling,reducing and reusing resources,achieve economic,social and environmental development of the organic unity. 展开更多
关键词 Tourism circular economy Development model Dynamic mechanism
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Mechanisms of species divergence through visual adaptation and sexual selection:Perspectives from a cichlid model system 被引量:3
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作者 Martine E.MAAN Ole SEEHAUSEN 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第3期285-299,共15页
The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can ... The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process,because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. Whendivergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence.Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selectionagainst intermediate phenotypes that are maladapted to their (sensory) environment. For Lake Victoria cichlids, the visual environmentconstitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigatethe direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours(red and blue) in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extractgeneral principles, and discuss future perspectives [Current Zoology 56 (3): 285-299, 2010]. 展开更多
关键词 CICHLID Sexual selection Species divergence Visual adaptation
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Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change 被引量:3
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作者 Niels SCHWAB Udo SCHICKHOFF +5 位作者 Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND 《Journal of Mountain Science》 SCIE CSCD 2017年第3期453-473,共21页
Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. ... Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths (3700-4200 m) at 50 plots in 2013 and 2014. We quantified species - environment relationships, i.e. the change of environmental conditions (e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species - environment relationships suggest that the investigated krummholz belt will largely prevent the upward migration of other tree constrain the future response species and thus of Himalayan krummholz treelines to climate warming. 展开更多
关键词 HIMALAYA Nepal Population structure Rhododendron campanulatum Spatial patterns Species-environment relationships Stand density Variation partitioning
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A Survey on Students' Group Discussion in Conversation Class 被引量:1
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作者 Cuiyun Cai 《Sino-US English Teaching》 2005年第11期75-78,共4页
This article makes an investigation of 114 English majors' level of a particular communicative performance and the general ability to perform in small-group conversations in their conversation class, and thereafter e... This article makes an investigation of 114 English majors' level of a particular communicative performance and the general ability to perform in small-group conversations in their conversation class, and thereafter explores the reasons for their current level with the aid of questionnaire based on a rating scale, together with observation and interviews. Some countermeasures are provided to call for teachers' attention in their teaching practice. 展开更多
关键词 INTERACTION small group interaction COUNTERMEASURES
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Design and Implementation of Novel Precision Internet Marketing Patterns under the Big Data and Cloud Environment 被引量:1
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作者 Zaixia HAN 《International Journal of Technology Management》 2015年第7期86-88,共3页
Nowadays most of the cloud applications process large amount of data to provide the desired results. The Internet environment, the enterprise network advertising, network marketing plan, need partner sites selected as... Nowadays most of the cloud applications process large amount of data to provide the desired results. The Internet environment, the enterprise network advertising, network marketing plan, need partner sites selected as carrier and publishers. Website through static pages, dynamic pages, floating window, AD links, take the initiative to push a variety of ways to show the user enterprise marketing solutions, when the user access to web pages, use eye effect and concentration effect, attract users through reading web pages or click the page again, let the user detailed comprehensive understanding of the marketing plan, which affects the user' s real purchase decisions. Therefore, we combine the cloud environment with search engine optimization technique, the result shows that our method outperforms compared with other approaches. 展开更多
关键词 Precision Internet Marketing Big Data Cloud Environment Pattern Classification.
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Preliminary study on the cultivation of Porphyra yezoensis in Bohai bay
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作者 ZHANG Xue WANG Hong +5 位作者 FANG Enjun GAO Yan GUO Biao LIU Kefeng XU Xiaofu CHEN Wei 《Marine Science Bulletin》 CAS 2019年第1期87-96,共10页
Sampling survey was carried out on the whole growth cycle(except the ice period from mid-January to mid-march next year)of Porphyra yezoensis breeding in Bohai Bay from late November 2017 to early May 2018,and the mar... Sampling survey was carried out on the whole growth cycle(except the ice period from mid-January to mid-march next year)of Porphyra yezoensis breeding in Bohai Bay from late November 2017 to early May 2018,and the marine environment factor were monitored at the same time.According to the the analysis of the growth condition of P.yezoensis and the environmental factors,the preliminary results confirmed that P.yezoensis could grow well in the Bohai Bay,the water temperature,salinity,pH and Nitrite are important environmental factors to limit its growth,if hanging net curtain in time when environmental conditions in the area is suitable for the growth of P.yezoensis that its growth period will be extended to five months.Survey also found that how to streak through the winter ice period is the key problems to be solved for P.yezoensis cultivation in the area,this study also puts forward two kinds of schemes,which is the effective method remains to be further tested. 展开更多
关键词 Bohai Bay P.yezoensis environment factor Cultivation mode
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Shifting Sands: A Review of Global Trends in the Current Business Environment and a Preview into the Future
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作者 Mansi Kapoor 《Journal of Modern Accounting and Auditing》 2017年第4期174-179,共6页
The paper highlights some of the changes that are taking place across the entire spectrum of business environment with an objective of understanding this new context. Politics is changing to reflect shifts in economic... The paper highlights some of the changes that are taking place across the entire spectrum of business environment with an objective of understanding this new context. Politics is changing to reflect shifts in economics which is simultaneously causing social strife and unrest. Technology has disrupted many business models and with rapid advancements will change the way we live, work, and interact with each other. So much so that this new reality is being termed as the fourth industrial revolution. We are clearly on the edges of the new times but are trying to make sense of it all ironically with a mindset which is anchored in the past. To be future ready, the future has to be forecasted or imagined or even willed by the collective consciousness of humanity. This paper has captured the changes through extensive research and personal insights into the changing paradigms. The paper finally puts forth two likely scenarios that might emerge which need to be further researched upon so that more conclusions can be drawn. 展开更多
关键词 GLOBAL TRENDS business environment technology REVOLUTION Bitnation
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