Road distance and travel time for an improved house price Kriging predictor     

Henry Crosby  Theo Damoulas  Alex Caton  Paul Davis  João Porto de Albuquerque  Stephen A. Jarvis 《地球空间信息科学学报》2018,21(3):185-194

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Towards a pro-community-based water resource management system in Northwest Cameroon: practical evidence and lessons of best practices     

Tantoh  Henry Bikwibili  Simatele  Danny Mulala  Ebhuoma  Eromose  Donkor  Kwabena  McKay  Tracey J. M. 《GeoJournal》2021,86(2):943-961

This paper examines community-based water supply management (CBWSM) in three rural districts of Northwest Cameroon as well as a review of the literature focusing on some successful community-based natural resource management initiatives in sub-Saharan Africa. Using empirical and secondary data collected through participatory research methods, it is argued that CBWSM has failed to achieve sustainable water supplies in Northwest Cameroon. Findings revealed that centralized control, the prevalence of poverty, passive involvement of public, private and grassroots community has continued to thwart water supplies within these districts. It is important to note that in any natural resource management system, power becomes a crucial factor as it determines who has and does not have access to common-pool resources. This paper argues that argues that strong traditional leadership, resolute devolution, and active participation of rural communities will facilitate and invigorate a platform for capturing the views of diverse user groups and this can bring about a people-centered and community-driven development process. Some aspects of best practice arising from successful case studies in Cameroon can contribute significantly to promoting the development of effective CBWSM in other rural communities with similar characteristics in and out of Cameroon. This will be possible only if rural groups are involved and engaged in the management of their resources while integrating some aspects of best practice.

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Location of hydrogen atoms in hydronium jarosite     

Henry J. Spratt  Maxim Avdeev  Michael C. Pfrunder  John McMurtrie  Llew Rintoul  Wayde N. Martens 《Physics and Chemistry of Minerals》2014,41(7):505-517

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A Representation of Tidal Currents Based on Energy Flux     

R. F. Henry  M. G. G. Foreman 《Marine Geodesy》2013,36(3):139-152

This article shows that the current associated with a tidal constituent can be represented as the sum of two vectors, one in phase with the surface elevation, the other in quadrature with the elevation. The in-phase component, which accounts for all the mean energy flux, resembles a traveling wave, while the quadrature component has some properties in common with standing waves.  相似文献   

信息技术对企业空间组织的影响——以诺基亚北京星网工业园为例   总被引：31，自引：4，他引：27  

刘卫东  Peter Dicken  杨伟聪 《地理研究》2004,23(6):845-855

最近通信技术的进展引发了对经济活动集聚和扩散力量的争论。本文以坐落于北京经济技术开发区的星网工业园为例 ,探讨在新的信息技术下地方企业集群的动力机制。过去几十年中 ,新的信息技术在经济空间变化中起着越来越重要的作用 ,但是它只是一种提供可能或促成发生的介质 ,并不是决定性的。新的信息技术的应用会导致企业的“虚拟集群” ,这是运用信息技术整合和缩短供应链的必然结果 ,但是零部件厂是否选择在地理空间上与整装厂集中在一起还取决于其他因素。在这个过程中 ,时间成本正成为企业空间组织的重要影响因素  相似文献   

The Regionalization of Chinese Business Networks: A Study of Singaporean Firms in Hainan,China     

Chia‐Zhi Tan  Henry Wai‐chung Yeung 《The Professional geographer》2000,52(3):437-454

This paper examines the central role of social and political institutions behind motivations and strategies of ethnic Chinese Singaporean investment in Hainan, China. Drawing upon 22 case studies of Singaporean firms in Hainan, we show that Singaporean investment in Hainan is embedded in Chinese business networks and their associated institutions. At the personal level, direct investments are largely motivated by the cultural attachments of Singaporean Hainanese to Hainan. Their small‐ and medium‐sized joint ventures largely reflect the characteristics of ethnically‐based Chinese business networks that stress connections, or guanxi. Similarly, the influence of social organizations (e.g., clan associations) and government institutions (e.g., public and quasi‐public agencies) on Singaporean investment strategies in Hainan reveals the significance of ongoing social relations institutionalized at the broader societal level.  相似文献   

Superlarge-scale structure in the Durham/UKST Galaxy Redshift Survey     

Andrei G. Doroshkevich  Richard Fong  Henry J. McCracken  rew Ratcliffe  Tom Shanks  Victor I. Turchaninov 《Monthly notices of the Royal Astronomical Society》2000,315(4):767-777

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Better constrained selection of the Paleozoic West Gondwana (South America) paleomagnetic poles for the APWP determination     

Bernard Henry  Mohamed E. M. Derder  Mohamed Amenna  Said Maouche  Boualem Bayou 《Studia Geophysica et Geodaetica》2017,61(2):185-198

The reliability of an Apparent Polar Wander Path (APWP) obviously depends on the paleomagnetic poles used to determine it. The APWP of Africa and South America are fairly well defined for the 330–260 Ma interval. However, this study pointed out a moderate shift between these two curves, and an incoherency of the South American data, contrary to the African ones, which are homogeneous. A number of South American pole positions were re-evaluated in an effort to better constrain the APWP for the entire continent. Most of discarded poles correspond to sites at the area of the junction of Cordillera with the stable craton. That could have structural implications for the evolution of the western margin of the Gondwana. A new criterion for the evaluation of paleomagnetic poles reliability for APWP is presented. Based on comparison of data from different continents and labeled “coherence” criterion, it is independent from Van der Voo’s ones.  相似文献   

Factors controlling variations in suspended sediment concentration for single-valued sediment rating curves,Fraser River,British Columbia,Canada     

Henry M. Sichingabula 《水文研究》1998,12(12):1869-1894

Functional (regression) and cause-and-effect analytical methods were employed in the investigation of factors controlling single-value sediment–discharge relationships for individual hydrological events in the Fraser River Basin. Of 1025 hydrological events identified in the 97 years of the 9-stations discharge record monitored by the Water Survey of Canada (1960–1988), 49 were associated with linear, non-linear (concave and convex) sediment rating curves. Analysis revealed that time of events offered a partial explanation for the occurrence of single-valued curves because events occurring in isolation or in quick succession did not always produce single-valued curves owing to variations in hydrograph characteristics and temporal and spatial peak attenuation factors. Hydrologically, linear and non-linear sediment rating curves were distinguished by the influence of preceding discharge or antecedent moisture, which tends to generate quick or delayed runoff, thereby causing rapid or slow increases in sediment concentration in concert with discharge changes. Hydraulically, linear curves were shown to be controlled by rates of stream bed scour (rising stage) similar to those for channel filling (falling stage); concave curves by rates of scouring (rising stage) similar to those of filling but different from those of rescouring (falling stage); and convex curves by rates of filling and scouring (rising stage) different from those of filling and rescouring (falling stages), all in relation to the timing of the exceedance of the threshold discharge for stream bed scour. Meteorologically, bed scour and fill approximately coincided with the timing of precipitation, if any, on the rising and/or falling stages under subzero (T≤0 °C), low (1≤T≤9 °C) and moderate (10≤T≤19 °C) temperature conditions. It is concluded that a combination of temporal, spatial, hydrological, hydraulic and meteorological factors control variations in sediment concentration during single hydrological events on the Fraser River in a complex fashion. Multivariate analysis of these factors should greatly improve prediction of sediment transport in the Fraser River Basin. © 1998 John Wiley & Sons, Ltd.  相似文献   

Characterizing solute transport in undisturbed soil cores using electrical and X‐ray tomographic methods     

P. A. Olsen  A. Binley  S. Henry‐Poulter  W. Tych 《水文研究》1999,13(2):211-221

Solute transport in undisturbed soil is a complex process and detailed information on the transport characteristics is needed to provide fundamental understanding of the processes involved. X‐ray computer tomography (CT) and electrical resistivity tomography (ERT) have been used to gain information on the transport characteristics. Both methods are non‐intrusive and do not disturb the soil, in contrast to other methods. CT provides high resolution information on bulk density and macropores, while ERT provides a three‐dimensional image of the internal resistivity structure. By adding a suitable solute under steady‐state flow, the internal resistivity changes can be interpreted as a change in resident concentrations. In our experiment two cores from different field sites were investigated. The ERT measurements revealed two transport modes (one fast and one slow) in one of the cores and only one mode in the other. This was consistent with the results of transfer function modelling on the independently measured breakthrough curves (BTCs). The fast transport mode is perhaps a result of many connected macropores, detected by CT, but this could not be verified with the ERT measurements because of the coarser resolution. However, with ERT in both cases we were able to explain the observed BTC qualitatively. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献