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121.
In the industrial risk field, Hazmat Logistics research is growing as a sector of special relevance. The road transport of these substances is an activity with an elevated risk, involving drivers, logistics systems, industries, infrastructures, urban areas, etc.In the study of risk and safety of the logistics of hazardous materials there is a special relevance for new and complex elements, as human factors and mental models involved in managing critical incidents ‘‘on the road”. Moreover, the ‘‘emergency management training” of human resources in this field is often limited, and this represents another factor of vulnerability.In collaboration with SBG (one of the leading European Hazmat Logistics corporations), we developed a quali-quantitative study on cognitive representations and semantic perceptions of risk and emergency management procedures in tanker drivers. The main innovation of the study, with the direct involvement of the stakeholder and 47 drivers, is represented by the construction and use of ‘‘ad hoc” psychometrical and knowledge-elicitation, allowing a deeper analysis of workers’ mental models.The application of PCP tools of adapted RepGrid and Landfield Laddering Procedures allows to analyze some of the main qualitative structures of mental models held by drivers about Hazmat Logistics. Through the analysis of these mental models, it could become possible to set up efficient preventive actions for this type of industrial risk. We are going to discuss the consequences of these findings and methodological approaches for the industrial risk-and-safety field.  相似文献   
122.
One of the basic assumptions of the travel cost method for recreational demand analysis is that the travel cost is always incurred for a single purpose recreational trip. Several studies have skirted around the issue with simplifying assumptions and dropping observations considered as nonconventional holiday-makers or as nontraditional visitors from the sample. The effect of such simplifications on the benefit estimates remains conjectural. Given the remoteness of notable recreational parks, multi-destination or multi-purpose trips are not uncommon. This article examines the consequences of allocating travel costs to a recreational site when some trips were taken for purposes other than recreation and/or included visits to other recreational sites. Using a multi-purpose weighting approach on data from Gros Morne National Park, Canada, we conclude that a proper correction for multi-destination or multi-purpose trip is more of what is needed to avoid potential biases in the estimated effects of the price (travel-cost) variable and of the income variable in the trip generation equation.  相似文献   
123.
An approach to sustainable municipal solid waste (MSW) management is presented, with the aim of supporting the decision on the optimal flows of solid waste sent to landfill, recycling and different types of treatment plants, whose sizes are also decision variables. This problem is modeled with a non-linear, multi-objective formulation. Specifically, four objectives to be minimized have been taken into account, which are related to economic costs, unrecycled waste, sanitary landfill disposal and environmental impact (incinerator emissions). An interactive reference point procedure has been developed to support decision making; these methods are considered appropriate for multi-objective decision problems in environmental applications. In addition, interactive methods are generally preferred by decision makers as they can be directly involved in the various steps of the decision process. Some results deriving from the application of the proposed procedure are presented. The application of the procedure is exemplified by considering the interaction with two different decision makers who are assumed to be in charge of planning the MSW system in the municipality of Genova (Italy).  相似文献   
124.
Historical decline in coral reef growth after the Panama Canal   总被引:1,自引:0,他引:1  
Guzman HM  Cipriani R  Jackson JB 《Ambio》2008,37(5):342-346
The Panama Canal is near its vessel size and tonnage handling capacity, and Panamanians have decided to expand it. The expansion of the Canal may consider the historical long-lasting impacts on marine coastal habitats particularly on sensitive coral reefs. These potential impacts were discussed during the national referendum as were other equally important issues, such as its effects on forests, watersheds, and water supply. Coral growth rates provide a direct measure of coral fitness and past environmental conditions comparable to analyses of tree rings. We examined stable isotopes, metal geochemical tracers, and growth rates on a century-long (1880-1989) chronology based on 77 cores of the dominant reef-building coral Siderastrea siderea collected near the Caribbean entrance to the canal. Our results showed a gradual decline in coral growth unrelated to changes in sea surface temperature but linked to runoff and sedimentation to coastal areas resulting from the construction and operation of the Panama Canal.  相似文献   
125.
Along the coast facing the Pacific Ocean in the province of Esmeraldas (Ecuador) one can observe some stretches where a process of rapid erosion is currently in progress. If it is not prevented, it seriously risks compromising the development of any form of utilization. In this paper, which summarizes the observations carried out in three different periods (1989, 1992 and 1999), we express the opinion that this process is the product of two distinct main causes. Along the Atacames bay, which may be considered as the main seaside resort of Quito, the capital of Ecuador, progressive cliff retreat is not only very dangerous for the existing tourist settlements, but also hinders their further development. The shoreline dynamics that seems to be due only to ‘natural’ causes (sea level rising, or the lastEl Niño event) are so active that defence works are not recommended. At Camarones the erosion of the coast is clearly due to the systematic destruction of mangroves by man. Also as a result of the lastEl Niño event, the situation has become alarming and it could rapidly get worse. By means of the present contribution, the Authors intend to attract the attention of the international scientific community upon the processes, not surveyed so far, affecting the ‘weakest’ stretches of the Ecuadorian coast.  相似文献   
126.
127.
A chrome tanning process which allows the reuse of tanning floats has been developed. The most commonly used chromium salts were replaced by highly masked and basified ones. This substitution eliminates basification operation and prevents pH change and the considerable neutral salts concentration increase in the tanning float. Consequently, tanning float can be reused several times. An optimum chromium salt concentration in the tanning float between 10% and 12.5% has been determined. It has been shown that the number of times the tanning float can be reused depends on the quality of the leather grain to be manufactured. In the best case, a saving of 18 L of water per kilogram of tanned leather is calculated. This means savings of 90% of water normally used.  相似文献   
128.
Sicyos polyacanthus is one of the most important weed in sugarcane crops of Tucumán (Argentina). The objective of this work was to establish strategies that would decrease the weed incidence in the crop to a minimum level. The study was carried out during 1998--2003 at five localities of sugarcane production of Tucumán (Argentina). The plots were 20 m long (192 m2) with 6 furrows and each plot was replicated five times. Treatments were: (i) Mechanical-chemical cultivation without fire; (ii) Mechanical-chemical culltivation with fire; (iii) Mechanical cultivation with handle pulled and with fire; (iv) Mechanical cultivation with handle pulled without fire; (v) Mechanical and chemical variants with fertilization and without fertilization; (vi) Mechanical and chemical variants with watering and without watering; (vii) Fallow and rotation, at the sugarcane crop renovation; (viii) Mechanical and chemical variants for plant cane and ratoon cane; and (ix) Mulching of harvest rests. The results suggest that besides the use of preemergent herbicides, fire marks the entry point of control, influencing fluxes and seed viability. It appears that fallow, mulching, and rotation of crops is fundamental for eliminating seeds that live short time in the soil and increase the mortality rate of species.  相似文献   
129.
The Venice Lagoon and its drainage basin form a vast system, where historical and recent cities, large and medium-small industrial districts and intensive agricultural activities coexist within a peculiar environment. The drainage basin constituted of an ensemble of tributary sub-basins with contrasting characteristics and freshwater fluxes; the hydraulic pathways are generally complex and not univocally established. With the main objectives to measure the annual freshwater discharge into the Venice Lagoon and to estimate the related load of pollutants, an intense field activity was carried out in the ambit of the DRAIN project. The 12 main tributaries of the drainage basin were monitored for more than 2 years (1998-2000), obtaining a relevant data set of hydrodynamic, physico-chemical and chemical data. Integrative investigations were also developed in a multidisciplinary approach, covering the existing knowledge gaps on the hydrology and behaviour of such a complex system. The paper describes the characteristics of the system, the selected approach to investigate it, and the main project outcomes.  相似文献   
130.
The subject of this theoretical study is a country park with a very delicate natural environment, located near large urban areas, as a result of which it receives a heavy inflow of visitors.The problem is that of determining the best organization of the park to achieve a distribution of visitors which is compatible with the protection of the natural environment. Therefore a mathematical model is sought which describes the distribution of visitors in relation to the various zones within the park.In this paper the mathematical model and its subsequent calibration are described.  相似文献   
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