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1.
This article presents the results of a three-year effort at applying information technology to the problem of collaborative natural resource management in San Diego Bay. As such, it represents an approach to integrated coastal zone management (ICZM). This effort resulted from a collaboration between the San Diego Supercomputer Center at the University of California, San Diego and the San Diego Bay Interagency Water Quality Panel for the purpose of (1) developing an environmental data repository to facilitate the acquisition and sharing of data and (2) the development of a visual model of the bay in support of the development of a comprehensive, coordinated management plan for San Diego Bay. It was determined from this study that information technology is an important and key component to ICZM but that sociopolitical factors may override the benefits of decision-support systems and should be considered at the outset of any project of this kind.  相似文献   
2.
This study explores the relationship between Australian's attitudes toward climate change impacts on the Great Barrier Reef (GBR) and environmentally responsible behavior (ERB). We hypothesize that general attitudes toward climate change, subjective norms, and perceived behavioral control predict intended and reported behavior, and that attitude negatively influences constraints on adopting ERB. The moderating effect of residential condition (urban vs. rural contexts) was tested across these hypothesized relationships. We randomly selected 200 individuals from eight regions: Five within 50 km of the GBR Coastline and three from the Statistical Metropolitan Areas in Australia. We yielded 1,623 surveys by telephone interviews. Findings confirm our hypotheses and suggest the most important predictor of intentions is perceived behavioral control. The two groups of respondents (urban vs. rural) illustrate different relationships. This study offers insight on how managers of the GBR can effectively shape residents' behavioral tendencies that minimize human impacts on the natural environment.  相似文献   
3.
This paper describes a model to synchronize the management and query of temporal and spatially referenced transportation data in geographic information systems (GIS). The model employs a method referred to as dynamic location, which facilitates spatial intersect queries from geographic shapes without the use of topological relationships. This is the inverse of how dynamic segmentation works in GIS. In contrast to dynamic segmentation, dynamic location stores geometry as an object within a single database field. This is an efficient, precise iconic model superseding the need for data decomposition into a complex set of tables. As an object model, the dynamic location process lends itself to high performance in an Internet, data-intensive, enterprise environment. Linear events are stored as {x, y} features, and not referenced to any route system. Route systems are built from {x, y, m} values (m for measure) and serve as number lines for mathematical operations. Any {x, y} object can then be referenced to either the Cartesian grid or any selected number line. This method offers the benefits of linear referencing, while making full use of a stable geodetic datum. Combinations of any {x, y} events may be placed over any {x, y, m} number line (route) and an intersect determined by looking through stacked {x, y, m} vertices of the coincident shapes. Since both geometry and shape reside in the same record, the use of “begin” and “end” dates facilitates full spatial and temporal version control. From a business process perspective, this creates a spatially enabled database, pulling GIS business functions back into the information technology mainstream.  相似文献   
4.
混凝土由于其适应性强,长期以来被选作重大隧道工程的材料,这就使得严密而准确的混凝土试验显得十分重要.由于不经过现场的准确试验,拌合物的性质将会在极大的范围内变化,其结果是产生质量问题和安全度的降低.  相似文献   
5.
Encouraging pro-environmental behavior among protected area visitors and other stakeholders has become a priority for marine resource managers. However, there exists a lack of understanding of the human dimensions of resource management regarding the perceptions and attitudes of stakeholders. Using the value-belief-norm theory of environmentalism (VBN) as a framework, the purposes of this investigation were to: 1) test a model of variables that influence stakeholders' intentions to adopt pro-environmental behavior in two marine protected areas (i.e., the Great Barrier Reef Marine Park and the Florida Keys National Marine Sanctuary); and 2) using the relevant literature and information gleaned from the model, suggest techniques that managers can use to encourage pro-environmental intentions. Acceptable goodness-of-fit indices for both of the structural equation models (one for each protected area) provided empirical support for the usefulness of the VBN framework to guide both research in marine contexts and marine protected area management efforts to encourage stakeholders' intentions to engage in pro-environmental behavior. Specific suggestions include increasing stakeholders. knowledge about impacts via environmental education strategies, increasing their awareness of their impacts and their efficacy in mitigating those impacts (e.g., workshops), and developing interpersonal relationships among managers and stakeholders (e.g., implementation intention and follow-up strategies).  相似文献   
6.
The future of US transport energy requirements and emissions is uncertain. Transport policy research has explored a number of scenarios to better understand the future characteristics of US light-duty vehicles. Deterministic scenario analysis is, however, unable to identify the impact of uncertainty on the future US vehicle fleet emissions and energy use. Variables determining the future fleet emissions and fuel use are inherently uncertain and thus the shortfall in understanding the impact of uncertainty on the future of US transport needs to be addressed. This paper uses a stochastic technology and fleet assessment model to quantify the uncertainties in US vehicle fleet emissions and fuel use for a realistic yet ambitious pathway which results in about a 50% reduction in fleet GHG emissions in 2050. The results show the probability distribution of fleet emissions, fuel use, and energy consumption over time out to 2050. The expected value for the fleet fuel consumption is about 450 and 350 billion litres of gasoline equivalent with standard deviations of 40 and 80 in 2030 and 2050, respectively. The expected value for the fleet GHG emissions is about 1360 and 850 Mt CO2 equivalent with standard deviation of 130 and 230 in 2030 and 2050 respectively. The parameters that are major contributors to variations in emissions and fuel consumption are also identified and ranked through the uncertainty analysis. It is further shown that these major contributors change over time, and include parameters such as: vehicle scrappage rate, annual growth of vehicle kilometres travelled in the near term, total vehicle sales, fuel economy of the dominant naturally-aspirated spark ignition vehicles, and percentage of gasoline displaced by cellulosic ethanol. The findings in this paper demonstrate the importance of taking uncertainties into consideration when choosing amongst alternative fuel and emissions reduction pathways, in the light of their possible consequences.  相似文献   
7.
Book reviews     
We show in this paper that the throughput data for the top 300 container ports reported each year by the various authorities follows a simple truncated lognormal distribution. This surprising phenomenon repeats itself every year from 1982 to 2006, despite many tumultuous changes in the container shipping world. The empirical data suggests that Gibrat's Law of proportionate growth indeed holds for the world container throughput data. Unfortunately, the classical stochastic growth model and other variants often used to explain the origin of this law appears to be too simplistic for the container terminal industry. We use instead the perspective that the container terminal throughput data are essentially an aggregate measure of the number of visitations as each container circulates on the world shipping network, and use this to propose a Markov chain based container circulation model to explain the origin of this phenomenon. Simulation results show that our network-based model is able to replicate the behavior of the empirical data to a reasonable degree of accuracy, and does not contradict the law of proportionate growth. More importantly, this model is able to replicate the relationship between the degree of connectivity of a port (i.e. number of linkages with other ports) and its association with the container throughput data, an empirical regularity which could not be explained using classical approaches.  相似文献   
8.
J. C. Sutton 《运输评论》2013,33(2):149-170

The ambulance service is the largest special needs transport operator in England and Wales and an important pillar of support to the National Health Service. In the last decade its size and role as a transport agency have been the subject of at least two government‐inspired reviews which have questioned the efficiency of the ambulance service and examined in some detail its operational performance. The ambulance service also faces constraints on its funding, like the rest of the health service, which raises questions as to its ability in the future to meet all patient demands for transport, especially in the area of non‐emergency outpatient services. The organization of the ambulance service is described from a number of perspectives: historical, institutional and managerial. These suggest that changes occurring in the approach to health care and management which are based on assumptions of cost‐effectiveness and competition, will likewise affect the organization and provision of patient transport services. The ambulance service may become an even more specialist operator competing or co‐operating in certain areas of work with other transport agencies especially in the area of non‐emergency outpatient services. Scenarios are outlined on how this may be achieved and the likely implications for the delivery of health care.  相似文献   
9.
During the period May 25–October 28, 2007, we collected data in face-to-face interviews on four sites in the North Carolina Research Reserve system. We subsequently conducted analyses on the effects of education, income, length of visitation, and frequency of visitation on visitor knowledge, perceptions, and attitudes regarding management. Visitors to the sites were well-educated, listed incomes above the state median, and were racially homogeneous. At the overall level, the majority (63%) knew who owned the sites, but only 43% correctly identified the managing agency. The majority also believed that overall conditions at the sites were stable, although those that had been visiting longer perceived conditions as deteriorating. Education was positively correlated with knowledge of ownership and management, and with support for additional rules and enforcement. Neither income, nor frequency of visitation showed any correlation with any of the dependent variables at the overall level. Some site-specific findings differed from the overall findings and varied from site to site. These differences were addressed individually.  相似文献   
10.
J. C. Sutton 《运输评论》2013,33(2):167-182
The changing role of Dial‐a‐Ride systems in the period 1969 to 1985 is reviewed as a case study in transport innovation. The first phase Dial‐a‐Ride systems were conceived and planned as transport services to complement and even replace conventional transit. However, their failure to attract any sizeable part of the public transport market combined with their high operating costs led to their demise in the mid‐1970s, to be superseded by the second phase Dial‐a‐Ride systems as paratransit services to the elderly and handicapped. These later systems were often initiated by community‐based transport agencies which have demonstrated their ability as transport innovators in meeting passenger needs. It is suggested that other transport services could learn valuable lessons from the experiences of community Dial‐a‐Ride, and that Dial‐a‐Ride itself will prove historically to be an important transitional agent in the reorganization of passenger transport services in the post‐deregulation environment of the late 1980s and 1990s.  相似文献   
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