我国三大地带国内旅游市场竞争态及转移分析     

姚宏  孙根年 《地域研究与开发》2008,27(3):53-57

国内旅游已经成为我国旅游市场的主体,对省级区域国内旅游市场竞争状况进行分析,可以进一步明确其发展竞争现状与局势.依据1996-2005年我国大陆31个省区市的国内旅游客流量统计指标,运用旅游市场竞争态及其转移理论,分析了1997,2001,2005年3个特征时段各省区市国内旅游市场竞争态,按东、中、西3个地带划分出各自的4种市场竞争态类型;并通过对3个时段的比较,揭示国内旅游市场竞争态的转移及核心驱动因素,将其归纳为相对稳定型、持续增长型、跳跃增长型、周期波动型、稳定回落型5种转移类型.  相似文献   

Evaluation of Procedures for Prediction of Unconventional Gas in the Presence of Geologic Trends     

Emil D. Attanasi  Timothy C. Coburn 《Natural Resources Research》2009,18(3):153-171

This study extends the application of local spatial nonparametric prediction models to the estimation of recoverable gas volumes in continuous-type gas plays to regimes where there is a single geologic trend. A transformation is presented, originally proposed by Tomczak, that offsets the distortions caused by the trend. This article reports on numerical experiments that compare predictive and classification performance of the local nonparametric prediction models based on the transformation with models based on Euclidean distance. The transformation offers improvement in average root mean square error when the trend is not severely misspecified. Because of the local nature of the models, even those based on Euclidean distance in the presence of trends are reasonably robust. The tests based on other model performance metrics such as prediction error associated with the high-grade tracts and the ability of the models to identify sites with the largest gas volumes also demonstrate the robustness of both local modeling approaches.

Emil D. AttanasiEmail:

  相似文献   

Competitive interactions among beam trawlers exploiting local patches of flatfish in the North Sea   总被引：5，自引：4，他引：1  

Rijnsdorp  A. D.; van Mourik Broekman  P. L.; Visser  E. G. 《ICES Journal of Marine Science》2000,57(4):894-902

  相似文献   

Measuring the need for primary health care: an index of relative disadvantage     

Ken Field   《Applied geography (Sevenoaks, England)》2000,20(4)

The prime objective of primary health care provision is the maintenance or improvement of the population's health. The equitable distribution of resources is paramount to this and measures of disadvantage are implemented to assess differential levels of need as a basis for calculating deprivation payments according to general practitioner workload. Despite research that highlights the benefits of measures of social disadvantage, indices have not been used to fundamentally shape resource allocation for health authorities. This paper uses the results from a patient survey into utilization behaviour to define and model the determinants of the need for health care based on components of relative need and accessibility. Proxy indicators are derived from routine sources of data to create an Index of Relative Disadvantage (IRD). A sensitivity analysis confirms the robustness of the index and shows that—although the index employs a wider range of variables than most previous deprivation indices—there is no gross data redundancy. Simplified versions of the index are also explored and evaluated. The IRD developed here is closely correlated with other indices of disadvantage, but its greater breadth and more logical construction mean that it may be more likely to be a more widely applicable instrument for health care planning of resource allocation.  相似文献   

Experimental study of the interspecific competition between two sibling marine herbivorous rotifers in relation to food availability and initial population density     

Divya S P  Kathiresan K  Asha P  Sekar V  Rajasekaran R 《海洋学报(英文版)》2012,31(4):113-126

Our laboratory study concerns the competitive interaction between two marine rotifer species Brachionus plicatilis and Brachionus rotundiformis at five algal (Nannochloropsis salina) concentrations (0.4×10⁶ to 32.4×10⁶ cells/ml) and at four initial inoculation densities (numerically, 100% B. plicatilis; 75% B. plicatilis and 25% B. rotundiformis, 50% each of the two species; 25% B. plicatilis and 75% B. rotundiformis and 100% B. rotundiformis. The initial biomass varied as 0.33 and 0.22 μg/ml for B. plicatilis and B. rotundiformis respectively. Experiments were performed at (25±1)℃. Population densities were enumerated and the medium was changed daily up to 8 d in the experiment. At the lowest food level tested, B. rotundiformis formed superior competitor than B. plicatilis, regardless of starting inoculation density. Generally when the food concentrations increased, B. plicatilis showed a greater increase in biomass than B. rotundiformis. B. rotundiformis formed the largest in population growth, regardless of increasing food concentrations. When grown alone, B. plicatilis reached peak abundances of (1.311 5±0.028) and (137.5±0.014) μg/ml at low and high food densities respectively. The corresponding values of B. rotundiformis were 0.724 5±0.016 and 18.15±0.021. The adverse effects of B. rotundiformis on the peak abundances of B. plicatilis were observed at the lowest food level and higher initial density. The rate of population growth in controls varied from (0.792±0.162) to (1.482±0.132) μm/d for B. plicatilis and (0.445±0.041) to (0.856±0.012) μm/d for B. rotundiformis, depending on food level. When both species were introduced together, low food levels favoured higher abundance of B. rotundiformis than B. plicatilis, suggesting that increased population density of the smaller B. rotundiformis was more successfull than larger B. plicatilis in brackish waters. Our work reveals that available food (type and quantity) along with starting inoculation density had significant effect on the interspecific competition between marine sibling rotifer species in zooplankton community structure.  相似文献   

Impact of land-use induced changes on agricultural productivity in the Huang-Huai-Hai River Basin     

《Physics and Chemistry of the Earth》2015

The water resource allocation is greatly influenced by the land use, agricultural productivity and farmers’ income. Therefore analyzing the impacts of land use changes on agricultural productivity and subsequent effects on farmer’s income is an important basis of the further study on the management mechanism and optimal water resource allocation. Taking the Huang-Huai-Hai River Basin as the study area, this study examined the impacts of conversion from cultivated land to built-up land from 2000–2005 and 2005–2008. Then the agricultural productivity was estimated with the Estimation System for Agricultural Productivity model, and the changes in agricultural productivity caused by land conversion were analyzed. Thereafter, Simultaneous Equations Model was used to analyze the impacts of the conversion from cultivated land to built-up land on the agricultural productivity and subsequent effects on farmer’s income. The results showed that: (1) The agricultural productivity was stable during the whole period, reaching about 2.84 ton/ha, 3.09 ton/ha and 2.80 ton/ha on average in 2000, 2005 and 2008, respectively, but the conversion from cultivated land to built-up land had important influence on the spatial pattern of agricultural productivity. (2) The land productivity, total power of agricultural machinery and the conversion from cultivated land to built-up land had an overall positive effect on the agricultural productivity. (3) The agricultural productivity and gross domestic product had positive influence on the farmers’ income, while the cultivated land area per capita and percentage of farming employee had negative influence, indicating that the farmer’s income was mainly contributed by non-agricultural income. These results in this study showed that optimal land use management can play an important role in promoting virtuous ecosystem cycle and sustainable socioeconomic development, which can also lay an important foundation for further research on the optimal allocation of water resources in the Huang-Huai-Hai River Basin.  相似文献   

高速铁路与国家地震台网信息接入及资源共享方式研究     

翟璐媛  黄志斌  杨陈  魏星  刘晓雨 《震灾防御技术》2015,10(3):646-656

本文对高速铁路与国家地震台网信息接入和资源共享方式进行了讨论。通过对组网模式和时延的分析及测试,在遵循目前地震系统信息传输模式的前提下,对于实时波形数据,可以根据实际情况采取国家中心型或者省局中心型的方式进行共享,用于高铁系统台站的补充,在地震预警发布阶段使用;对于地震速报信息,可以采取国家中心型的方式进行共享,用于地震信息的确认,在地震预警解除阶段使用。为了减小实时数据传输的时延以适应预警需求,应对数据采集器进行升级,并更新相应的流服务器的仪器适配器。  相似文献   

浅谈上海市地震局信息虚拟化建设     

王小明  李平  蔡长青  秦洪文 《震灾防御技术》2014,9(2):296-303

通过分析当前信息虚拟化技术的发展趋势,研究上海市地震局现有服务器存在的高功耗、低利用率等弊端,结合上海市地震局防震减灾大楼建设背景,提出了适合未来信息化发展的上海市地震局信息虚拟化建设方案。并基于刀片服务器、高性能存储、光纤交换机实现该方案,降低了能耗,提高了资源利用率,方便了服务器的统一管理,为数据库整合及桌面虚拟化工作打下了坚实基础。  相似文献   

深圳市入境旅游客源地竞争态变化趋势研究   总被引：2，自引：0，他引：2  

梁明珠  王倩 《世界地理研究》2010,19(2):78-83,77

深圳市入境旅游得到了快速的发展,但是一直缺乏相关研究。本文采用了市场竞争态模型对深圳市主要入境旅游客源地进行分析,总结出主要客源地的市场竞争态,继而针对不同的市场态势采取不同的发展策略。并针对该模型存在的不足,使用一元回归预测方法进行弥补,由此得出深圳市不同的市场态势及相应的旅游发展策略。  相似文献   

虚拟区域与城市竞合研究——对扬州区域发展战略的实证研究     

田冬  罗小龙  杨效忠  郑焕友 《世界地理研究》2010,19(4):98-105

基于虚拟区域理论视角,对扬州进行实证研究,探讨长三角虚拟区域和城市竞合的关系。研究认为多层次的虚拟区域已经在长三角出现,城市在空间定位、产业发展和基础设施建设上存在诸多竞争。与此同时,为缓和城市竞争,城市合作开始出现并不断深入,合作形式也越加多样。研究也指出各自利益考量浮现虚拟小区域、合作机制薄弱和省管县体制对区域一体化的负面影响等新问题,并提出相关对策建议。  相似文献