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141.
This research explores the factors that shape the evolving geographic distribution of business headquarters (HQ) activity. We address an understudied influence on HQ geographies: metropolitan HQ changes driven by the process of small, rapidly expanding businesses growing into mature companies. This investigation focuses on the developmental paths followed by fast-growing firms (FGFs) and the geographic distinctions that can be observed in a FGF tracking study of Canada’s metropolitan regions from 1987 to 2005. Our research findings indicate that geography plays an important role in this development, as FGF tracking records throughout Canada’s metropolitan areas diverge sharply. We find that most FGFs that emerged in Vancouver and Toronto continued as ongoing businesses following their rapid growth phase, while a high proportion of FGFs based in Montréal and Calgary did not. These results contribute to a greater understanding of metropolitan economies, business development, and HQ location in Canada 相似文献
142.
Extreme rainfalls in Eastern Himalaya and southern slope of Meghalaya Plateau and their geomorphologic impacts 总被引:3,自引:0,他引:3
This paper presents the detailed rainfall characteristics of 3 key areas located in the eastern monsoon India: the margin of Darjeeling Himalaya, the margin of Bhutanese Himalaya and the Cherrapunji region at the southern slope of Meghalaya Upland. All these areas are sensitive to changes but differ in annual rainfall totals (2000–4000 mm, 4000–6000 m and 6000–23,000 mm respectively) and in the frequency of extreme rainfalls. Therefore the response of geomorphic processes is different, also due to various human impact. In the Darjeeling Himalaya the thresholds may be passed 2–3 times in one century and the system may return to the former equilibrium. At the margin of western Bhutanese Himalaya in 1990s, the clustering of three events caused an acceleration in the transformation and formation of a new trend of evolution, especially in the piedmont zone. In the Cherrapunji of Meghalaya region in the natural conditions the effects of dozens of extreme rainfalls every year were checked by the dense vegetation cover. After deforestation and extensive land use the fertile soil was removed and either the exposed bedrock or armoured debris top layer protect the surface against degradation and facilitate only rapid overland flow. A new “sterile” system has been formed. 相似文献
143.
Maxim Shoshany Asaf Even‐Paz Shlomo Bekhor 《International journal of geographical information science》2013,27(7):777-797
Recent developments in sensing and tracking technologies have enabled large geographical databases to be established that represent spatial dynamics of ‘behavioral entities’. Within this type of dynamics there are several levels and modes of organization that need to be revealed. Clusters are high‐level groupings of entities, where change in their location and form, including split and merge events, represents self‐organization and functioning patterns. Such information may contribute for better understanding spatially complex dynamic patterns. The main objective of this article is to develop an adaptable methodology that facilitates exploration of spatial order and processes in point pattern dynamics. The approach presented here utilizes data‐clustering at each snapshot of the moving pattern, and then involves pairwise linking between the clusters identified at each snapshot and those identified in the following snapshot. Such linking is based on a new methodology that defines well globally optimized solutions for numerous possible linking combinations based on Linear Programming. A preliminary assessment of the approach was conducted with an existing Ants' simulation tool, capable of creating data sets covering in detail a substantial portion of the nest's life cycle. 相似文献
144.
145.
采用聚类分析法,对北方农牧林交错带上的科尔沁右翼前旗的土地利用类型进行了分类,在此基础上,对各土地利用区的土地利用类型及结构特点进行了分析与评价,并对今后合理利用土地资源提出了意见。 相似文献
146.
全球-地方出口溢出效应对新企业进入出口市场的影响 总被引:4,自引:2,他引:4
出口增长是驱动中国经济发展的关键力量,新出口企业进入是出口增长的微观体现。新贸易理论认为集聚外部性带来的知识溢出是影响企业出口决策的关键因素。出口地、目的国维度的知识溢出均有利于企业获取必要的出口知识,降低进入出口市场的难度。演化经济地理理论强调认知邻近是出口溢出发挥作用的前提,出口地、目的国维度的出口经验、产品关联是出口溢出的主要内容。论文利用2002—2011年中国海关贸易数据库,分析出口地、目的国溢出对新企业进入出口市场的作用。结果发现:① 出口溢出可以显著提升新出口企业进入概率,私营企业更倾向于进入出口溢出更强的出口地、目的国市场;② 出口溢出对跟随型企业,特别是本土跟随型企业进入的促进作用更强,国有集体企业更强调整体出口经验溢出,私营企业更强调产品知识溢出;③ 出口地溢出有利于新出口企业拓展到新目的国,目的国溢出有利于新出口企业拓展到新产品。论文完善了出口企业空间动态研究,拓展了出口溢出对出口决策作用的空间维度,也有助于深化对中国贸易空间的理解。 相似文献
147.
This paper attempts to clarify the meaning of corporate social responsibility (CSR) in the context of the European maritime sector and examines its application in the case of the Greek-owned short sea shipping companies. CSR is assessed in terms of a number of variables such as employees’ satisfaction, corporate productivity and efficiency, social welfare, awareness and social accountability of managers and directors, et al. Focus is given on the applicability of CSR to shipping companies of small and medium size. For this purpose a survey has been conducted. Based on the findings of the qualitative research performed, it is concluded that the application of CSR is restricted only to companies that either are subsidiaries of international conglomerates or owned by ship-owners personally aware of the corporate benefits derived from social responsible behaviour . Based on improved knowledge of managers’ and directors’ attitudes and views towards CSR solutions, the paper offers some ways forward for policy informing. 相似文献
148.
Koji Nishiyama Shinichi Endo Kenji Jinno Cintia Bertacchi Uvo Jonas Olsson Ronny Berndtsson 《Atmospheric Research》2007,83(2-4):185-200
In order to systematically and visually understand well-known but qualitative and complex relationships between synoptic fields and heavy rainfall events in Kyushu Islands, southwestern Japan, during the BAIU season, these synoptic fields were classified using the Self-Organizing Map (SOM), which can convert complex non-linear features into simple two-dimensional relationships. It was assumed that the synoptic field patterns could be simply expressed by the spatial distribution of (1) wind components at the 850 hPa level and (2) precipitable water (PW) defined by the water vapor amount contained in a vertical column of the atmosphere. By the SOM algorithm and the clustering techniques of the U-matrix and the K-means, the synoptic fields could be divided into eight kinds of patterns (clusters). One of the clusters has the notable spatial features represented by a large PW content accompanied by strong wind components known as low-level jet (LLJ). The features of this cluster indicate a typical synoptic field pattern that frequently causes heavy rainfall in Kyushu during the rainy season.In addition, an independent data set was used for validating the performance of the trained SOM. The results indicated that the SOM could successfully extract heavy rainfall events related to typical synoptic field patterns of the BAIU season. Interestingly, one specific SOM unit was closely related to the occurrence of disastrous heavy rainfall events observed during both training and validation periods. From these results, the trained SOM showed good performance for identifying synoptic fields causing heavy rainfall also in the validation period. We conclude that the SOM technique may be an effective tool for classifying complicated non-linear synoptic fields and identifying heavy rainfall events to some degree. 相似文献
149.
Clustering debris-flow events, namely many debris flows simultaneously triggered by a regional rainstorm in a large-scale mountainous area, occurred in four regions of Wenchuan earthquake stricken areas in 2008 and 2010. The characteristics of the clustering debris flows are examined with regard to triggering rainfall, formation process, and relationship with the earthquake by field survey and remote sensing interpretation. It is found that the clustering events occurred nearly at the same time with the local peak rainstorms, and the rainfall intensity-duration bottom limit line for clustering debris flows is higher than the worldwide line. It means that more rainfall is needed for the occurrence of the clustering debris flows. Four kinds of major formation processes for these debris flows are summarized: tributary-dominated, mainstream- dominated, transformation from slope failures, and mobilization or liquefaction of landslide. The four regions has a spatial correlation with the strong- quake-influenced zone with the peak ground acceleration = 0.2 g and the seismic intensity 〉 X. 相似文献
150.
苟浩锋 《沙漠与绿洲气象(新疆气象)》2020,14(1):108-114
利用兰州地区2013—2018年4—10月139个自动气象站逐时累积降水量和降水小时数资料,通过K均值聚类分析方法进行二维聚类分区,分析不同区域降水精细化时空分布特征。结果表明:(1)K均值聚类方法将兰州地区降水划分为3个区域,年平均降水量分别为246、317和427 mm,降水小时数分别为306、404和454 h。分区结果同地理位置、地形高度相适应,与主观分区结果较一致但更加科学精细;(2)3个区域降水分布特征相似,但也存在较明显的地域性差异,降水量集中在7—8月,分别占46%、45%、44%,降水小时数集中在6—9月,分别占55%、53%和53%;(3)从日变化特征看,降水量、降水小时数、降水强度的高值分别集中在7—8月的午后至前半夜、7月的16—17时、8月的00—04时和16—23时。 相似文献