Overcoming Trade Impediments: Considering SME Exporters from Nova Scotia     

Ronald V. Kalafsky  Darlene T. Duggan 《The Professional geographer》2016,68(4):613-623

Firms often encounter location-based impediments that hinder them from engaging with international markets. These challenges can be exacerbated for smaller firms, which often have limited resources and exposure to global markets. This article examines successful small and medium-sized exporters from Nova Scotia, a province with decreased export activity in recent years. It explores these firms’ trade-related motivations, their impediments, and the strategies that they have used to address possible location-related problems. Although geographical distance does not appear to be a competitive challenge, other issues emerge, including travel expenditures and the costs of export intelligence gathering. Successful exporters have overcome many potential impediments by using government trade programs, establishing and maintaining face-to-face contacts, and working with international partners.  相似文献   

现代海底块状硫化物矿床储量估算方法探讨     

张柏松 《地质与勘探》2018,54(4):723-734

海底块状硫化物矿床具有巨大的经济价值和良好的开发前景。但是由于勘探难度和技术手段的限制,在全球已经发现的600多个海底热液喷口和硫化物矿床中,不到5%的矿床进行了详细的勘探,进行资源量计算的矿床更是屈指可数。选择适当的方法估算储量对于深海资源开发意义重大。本文系统总结了前人估算海底硫化物储量的方法,并以勘探程度相对较高、数据资料相对丰富的Atlantis-II-Deep矿床和Solwara 1矿床为例,评析了前人采用不同储量计算方法得到的结果和各种方法计算的准确性;针对有一定钻孔数据的TAG硫化物堆丘,采用距离反比法重新计算了储量,并和块段法估算的结果进行对比。得到以下结论:(1)海底硫化物矿体形态是制约储量估算方法适用性的一个重要因素;(2)传统几何法可以在极低勘探条件下估算海底硫化物储量量级;(3)对于海底硫化物储量估算,地质统计学的精度高于传统几何法;(4)较高勘探条件下距离反比法可以与地质统计学相互对照、验证;(5)在一定钻孔数量的条件下,可以应用距离反比法进行海底硫化物储量估算。  相似文献   

Study on Water Internal Recycle Process and Mechanism in Typical Mountain Areas of Inland Basins,Northwest China: Progress and Challenge     

Yongjian Ding  Shiqiang Zhang 《地球科学进展》2018,33(7):719-728

The water resource and its change of mountainous area are very important to the oasis economic system and ecosystem in the arid areas of northwest China. Accurately understanding the water transfer and circulation process among vegetation, soil, and atmosphere over different hydrological units in mountainous areas such as snow and ice, cold desert, forest and grassland is the basic scientific issue of water research in cold and arid regions, which is also the basis of water resource delicacy management and regulation. There are many research results on the hydrological function of different land covers in mountain areas, basin hydrological processes, however, there are only very limited studies on the water internal recycle at basin scale. The quantitative study on the mechanism of water internal recycle is still at the starting stage, which faces many challenges. The key project “Study on water internal recycle processes and mechanism in typical mountain areas of inland basins, Northwest China” funded by National Natural Science Foundation of China will select the Aksu River and Shule River Basin, which have better observation basis, as study area. The internal mechanism of moisture transfer and exchange process of different land cover and atmosphere, the internal mechanism of water cycle in the basin, and water transfer paths in atmosphere will be studied through enhancing runoff plot experiments on different land cover, analyzing the mechanism of water vapor transfer and exchange between different land covers in the watershed by isotope tracing on the water vapor flux of vegetation water, soil moisture and atmospheric moisture, improving the algorithms of remote sensing inversion and ground verification on land surface evapotranspiration on different land cover, and analyzing the water vapor flux from reanalysis data, and the coupling modeling of regional climate model and land surface process model. At last, the effect of different land cover in hydrological process of mountain area, and the impact of land cover on downstream oasis will be systematically analyzed.  相似文献   

Revisiting the death of geography in the era of Big Data: the friction of distance in cyberspace and real space   总被引：1，自引：0，他引：1  

Su Yeon Han  Keith C. Clarke 《International Journal of Digital Earth》2018,11(5):451-469

Many scholars have argued that the importance of geographic proximity in human interactions has been diminished by the use of the Internet, while others disagree with this argument. Studies have noted the distance decay effect in both cyberspace and real space, showing that interactions occur with an inverse relationship between the number of interactions and the distance between the locations of the interactors. However, these studies rarely provide strong evidence to show the influence of distance on interactions in cyberspace, nor do they quantify the differences in the amount of friction of distance between cyberspace and real space. To fill this gap, this study used massive amounts of social media data (Twitter) to compare the influence of distance decay on human interactions between cyberspace and real space in a quantitative manner. To estimate the distance decay effect in both cyberspace and real space, the distance decay function of interactions in each space was modeled. Estimating the distance decay in cyberspace in this study can help predict the degree of information flow across space through social media. Measuring how far ideas can be diffused through social media is useful for users of location-based services, policy advocates, public health officials, and political campaigners.  相似文献   

A model for integrated spatial land use characteristics linking to surface nutrient concentration   总被引：1，自引：0，他引：1  

Erqi Xu 《International Journal of Digital Earth》2018,11(10):1064-1084

Quantifying land use heterogeneity helps better understand how it influences biophysical systems. Land use area proportions have been used conventionally to predict water quality variables. Lacking an insight into the combined effect of various spatial characteristics could lead to the statistical bias and confused understanding in previous studies. In this study, using spatial techniques and mathematical models, a diagnostic model was developed and applied for quantifying and incorporating three spatial components, namely, slope, distance to sampling spots, and arrangement. The upper catchment of Miyun Reservoir was studied as the test area. Total nitrogen, total phosphorus, and chemical oxygen demand of water samples from field measurements were used to characterize the surface water quality in 52 sub-watersheds. Using parameter calibrations and determinations, combined spatial characteristics were explored and detected. Adjusted land use proportions were calculated by spatial weights of discriminating the relative contribution of each location to water quality and used to build the integrated models. Compared with traditional methods only using area proportions, our model increased the explanatory power of land use and quantified the effects of spatial information on water quality. This can guide the optimization of land use configuration to control water eutrophication.  相似文献   

TRANSIT: a GIS toolbox for estimating the duration of ancient sail-powered navigation     

Gianmarco Alberti 《制图学和地理信息科学》2018,45(6):510-528

Cost-surface analysis in Geographic Information System (GIS) environment has been less frequently used in the study of ancient sail navigation than in other studies of the human past. Navigation cost-surface analysis entails the use of GIS tools that are versatile but not very easy to grasp and to put to work. This article describes an ArcGIS toolbox built to facilitate cost-surface analysis of ancient sail navigation. It estimates the navigation time from a start location, considering parameters relevant for the generation of an accumulated anisotropic cost-surface, automating the complex workflow required to meaningfully pre- and post-process the data. Acknowledging the limitations inherent to the tool, and to the modeling of a complex matter such as sail navigation, the toolbox is first described and then used in a worked example. Historically recorded voyages in the Mediterranean during classical antiquity are compared to estimated durations generated by the toolbox. In spite of structural and expected limitations, the results indicate that the proposed toolbox may produce reasonable estimates. These should be thought of as values gravitating around, not matching, likely past durations. The estimated values may prove useful as an indication of the order of magnitude of past voyages’ duration, and as frame of reference in measuring ancient maritime space through time.  相似文献   

热带气旋西行造成的远距离降雨特征分析          下载免费PDF全文

姜艳 《高原山地气象研究》2019,39(1):20-25

2018年7月27~28日凉山州地区出现了持续性的强降水天气过程,本文运用水平分辨率为1°×1°的NECP6小时再分析资料、新型监测资料及常规观测资料进行分析。发现此次过程不同于常规的降水过程,环流背景上受副高外围的东南气流和热带气旋形成的东风波倒槽共同作用形成的急流轴影响,为降水地提供充足的水汽和能量补充,从而形势上形成了热带气旋远距离降水,同时副热带高压的稳定维持也阻挡了高原上的低值系统快速东移,使得降水机制长时间停滞,对降水地造成影响。  相似文献   

梅江河流域年均降雨量空间插值方法研究   总被引：10，自引：0，他引：10  

刘胤雯  赖格英  陈元增  黄丽 《亚热带资源与环境学报》2007,2(3):29-34

分析了降雨空间分布的影响要素及降雨空间插值的主要方法,并在此基础上,利用地理信息系统(GIS)的空间分析功能,综合考虑高程、坡度、坡向等影响降雨空间分布的多种要素,应用协克里金方法,探讨流域降雨量的空间插值问题及其应用,并与反距离权重法、克里金方法等单要素方法进行了降雨空间插值的效果比较.结果表明:应用协克里金方法,在综合考虑高程、坡度、坡向等影响要素的条件下,对降雨进行空间插值,其结果具有比较好的精度.  相似文献   

2007年宁洱6.4级地震强震动观测记录   总被引：2，自引：0，他引：2  

崔建文  李正光  赵云旭 《地震研究》2007,30(4):384-388

"十五"期间建设并投入试运行的中国数字强震动台网云南区域台网有20多个强震动台站记录到宁洱6.4级地震产生的地面运动。记录的最大峰值加速度为431.2cm/s2,这是我国大陆自开展强震动观测以来在一次强震中同时获取记录最多的一次,初步展现了"十五"强震动台站建设的成效。  相似文献   

中国滑雪场可达性及市场潜力测度   总被引：1，自引：0，他引：1  

窦文康  王世金  韩彤彤  颉佳 《地理科学》2021,41(2):319-327

利用可达性分析方法与潜力模型对中国滑雪场空间分布格局与市场潜力进行了系统分析,全面认识了滑雪场在交通可达性方面的优劣势,并针对不同区域提出了相应的发展或改进方向.研究表明:中国滑雪场距离城市中心的平均最短旅行时间为1.24 h,南方可达性普遍较差,北方同一城市内部差异较大.全国各城市到达某一滑雪场的最短时间呈圈层式分布...  相似文献