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591.
One of the major barriers to addressing complex social–ecological issues through integrated coastal management (ICM) is a lack of intergovernmental coordination and cooperation (horizontal and vertical fragmentation). This article describes an effort to overcome the barriers to ICM in Sri Lanka by fostering intergovernmental collaboration and initiating adaptive governance to restore one town, Hikkaduwa, and its associated marine protected area (MPA) and coastal zone habitats. Administrators from 12 national and local governmental agencies that are responsible for aspects of coastal management in the town of Hikkaduwa participated in a series of formal and informal workshops and a week-long tour of ICM projects in the Philippines. Outcomes demonstrate that these informal and formal meetings, workshops, and travel experiences fostered trust, social capital, and attitudinal organizational commitment (AOC). The experiences motivated members to overcome vertical and horizontal governance fragmentation through the formation of an independent intergovernmental committee for the restoration of Hikkaduwa into a sustainable and resilient community. ICM activities undertaken by the newly formed organization suggest that internal leadership capacity, effective local–national partnerships, explicitly linked ecological–economic projects, and long-term commitment are necessary conditions for success. Overall, attainment of sustainability and resilience through successful ICM should be thought of as a journey and not a destination. 相似文献
592.
Timothy B. Werner Luis Paulo Pinto Guilherme Fraga Dutra Paulo Gustavo Do Prado Pereira 《Coastal management》2013,41(1):99-108
The Abrolhos bank, an area of continental shelf off the coast of Bahia, Brazil, has the most biologically diverse coral reefs in the entire southern Atlantic Ocean. The coral reefs and nearby coastal ecosystems constitute a global conservation priority and are the target of the Abrolhos 2000 project, initiated by Conservation International as part of its global marine conservation strategy. Although portions of the Abrolhos reefs are located within a marine park, they are not afforded adequate protection due to insufficient conservation resources and a failure to be part of a broader integrated coastal management program. Through partnerships with government agencies, nongovernmental organizations, local communities, the private sector, and other stakeholders, Abrolhos 2000 is working to provide these needs while establishing local capacity for conserving coastal and marine ecosystems. The project's initial successes provide examples of useful strategies for making integrated coastal management work in the context of emerging economies. 相似文献
593.
Intermodal road-rail freight transport works best within markets with relatively large flows occurring over long distances, which corresponds poorly to the current demand for transport in the European Union. The purpose of this paper is to compare the capabilities of conventional European intermodal transport, with special reference to the competitiveness in markets with small flows over short distances, and to explore innovative concepts. Using a technological systems approach, key functions are identified as being the inducement and blocking mechanisms that affect the development and diffusion path of this 'small flows over short distances' (SFSD) system, providing a tool for empirical delineation of the system. These concepts are illustrated and analysed through a case study of the Swedish development project Light-combi. The results show that market and financial uncertainties, insufficient network connectivity and policies favouring the existing technology paradigm, severely hamper the development and diffusion of SFSD systems. 相似文献
594.
595.
Yang J.Wei B.Qi S.Guo W. 《现代隧道技术》2018,(6):183-190
The CCS Hydropower Station in Ecuador is a water diversion type power station, in which two superdeep vertical shafts with depth of 537.9 m are arranged. After comparison of alternative options, a new type of 1088DC RHINO raise boring machine was chosen to construct the vertical shafts. The construction process with the raise boring machine is divided into 3 stages, i.e. pilot hole construction by forward drilling, pilot shaft construction by reverse expanded excavation and shaft construction by manual expanded excavation. In view of the problems of buried drill bits and pilot hole deflection in the first stage, the problems of shaft collapse and cutter damage in the second stage, and the problems of collapse, water inflow and shaft blocking in the third stage, some preventive and treatment measures were proposed based on causes analysis, and good construction effect was achieved. The success- ful construction of super-deep vertical shafts at CCS hydropower station with raise boring method is significant to improve the construction level of deep shafts of domestic water conservancy and hydropower engineering, and the re- lated research can provide a reference for the similar shaft engineering construction. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved. 相似文献
596.
Demographic ageing is a key societal challenge in Europe as well as in many other western and non-western societies. A crucial dimension concerns elderly daily mobility patterns. While still partaking fewer and shorter trips than younger generations, today’s elderly have been found increasingly (auto)mobile. Although the elderly benefit from the independence, freedom of movement, and social inclusion, concerns may rise regarding the environmental and accessibility impacts of this induced mobility. The present study adds to the expanding literature on elderly mobility, an integrated analysis of the effects of socio-demographic, health, trip, spatial and weather attributes on elderly mobility. Utilizing travel diary data for Greater Rotterdam, The Netherlands, trip frequencies and transport mode choices of the elderly are analysed by means of zero-inflated negative binomial models as well as multinomial logit regression models, and contrasted to the non-elderly subpopulation to explore (dis)similarities. While the results show common determinants, the models also highlight important differences in the magnitude of the estimated coefficients and factors only influencing transport patterns for the elderly. Embedded in the context of an aging population, the empirical findings assist policy-makers and planners in several respects: For transportation plans and programs it is critical to recognize mobility needs of the elderly. As the seniors are becoming increasingly automobile, the results call for strategies to encourage older people to use more physically active and environmentally friendly transport modes such as public transport, walking and cycling. 相似文献
597.
The goal of this paper is to better understand home-to-work travel distances throughout the Montréal Metropolitan region.
A simultaneous equation modelling analysis is carried out to jointly explain commuter trip length and home–work location as
a function of neighbourhood typologies, commuter socio-demographics and measures of job and worker accessibility. First, a
factor and cluster analysis of urban form is performed over the entire region on a fine-scale grid pattern. The outcome of
this analysis is the classification of typologies at both home and job locations. Different measures of accessibility and
commuter socio-demographics are then incorporated into the analysis. Varied data sources including a detailed Montréal Origin–Destination
Survey on over 30,000 home-to-work automobile trips are analyzed. Among other results, commuters that live and work in a different
sub-region almost double the average trip distance and although socio-economic factors have a statistically significant correlation
with commuter distance, these factors have a marginal effect. Interestingly, our results highlight the importance of urban
form and job accessibility. Deciding on whether to live and work in the same sub-region was modelled as an endogenous binary
random utility model; unobserved heterogeneities seem to be simultaneously influencing both the home–work location choice
and trip-to-work distances. Our results underscore the importance of home–work location with respect to urban form and job
accessibility. Hence, policies that support more dense and mixed land-use in suburban areas would not be enough to reduce
commuter distances. These actions should be accompanied by other policy initiatives to discourage long car trips. 相似文献
598.
The development of microchannels with open flow for use in irrigation and rainy areas is challenged by electricity generation via hydrokinetic devices in shallo... 相似文献
599.
There are many ways of describing a solid,porous or fluid region of the computational domain when solving the Navier-Stokes equations(NSE)for flow motions.Amongst these the porous cell method is one of the most flexible approaches.In this method,a parameter is defined as a ratio of the volume open to water and air in a calculation cell to its cell volume.In the calculation,the same numerical procedure is applied to every cell and no explicit boundary conditions are needed at solid boundaries.The method is used to simulate flow through porous media,around solid bodies and over a moving seabed.The results compare well with experimental data and other numerical results.In our future work the porous cell method will be applied to more complex fluid-solid interaction situations. 相似文献
600.
Dan B. Marghitu David G. Beale S.C. Sinha 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》1997,28(1):41-55
Computer simulations of a driven vehicle are performed to assess and quantify the automobile stability. The analytical methodology is based on PoincarS maps and Floquet theory, which are commonly used to investigate the stability of periodic systems. The approach accommodates the study of the complex dynamics of vehicle locomotion under various configurations of the system. The proposed method does not require any knowledge regarding the inner structure of the vehicle model. Kinematic data is simply collected at the specific instants to conduct the analysis. It is found that this method has the potential for real time warning and control of vehicle instabilities. 相似文献