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131.
Air Pollution Potential: Regional Study in Argentina   总被引:4,自引:0,他引:4  
/ Air pollution potential is a measure of the atmospheric conditions that are unable to transport and dilute pollutants into the air, independently of the existence of sources. This potential can be determined from two atmospheric parameters: mixing height and transport wind. In this paper a statistical analysis of the mixing height and transport wind, in order to determine the areas with high or poor atmospheric ventilation in Argentina, is presented. In order to achieve this, meteorological data registered during 1979-1982 at eight meteorological stations were used. Daily values of the maximum mixing height were calculated from observations of daily temperatures at different heights and maximum surface temperature. At the same time as the maximum mixing height, the values of the transport wind were determined from the surface windspeed and the characteristics of the ground in the surroundings of each meteorological station. The mean seasonal values for both parameters were obtained. Isopleths of the mean seasonal of the maximum mixing heights were drawn. The percentage of seasonal frequencies of poor ventilation conditions were calculated and the frequency isopleths were also drawn to determine areas with minor and major relative frequencies. It was found that the northeastern and central-eastern regions of Argentina had a high air pollution potential during the whole year. Unfavorable atmospheric ventilation conditions were also found in the central-western side of the country during the cold seasons (37.5% in autumn and 56.9% in winter). The region with the greatest atmospheric ventilation is located south of 40 degrees S, where the frequency of poor ventilation varies between 8.0% in summer and 10.8% in winter.  相似文献   
132.
Nanotechnology has the potential for the development of new materials and processes that can substitute for toxic materials now used in industry. Excitement over this possibility is tempered, however, by the potential adverse environmental health and safety aspects of the new nanomaterials. Although a few examples from the literature are encouraging, e.g., wire and cable insulation, great care must be taken to perform complete alternatives assessment evaluations of any new nanotechnology-enabled product before its adoption.  相似文献   
133.
Within modern society, business organizations have a co-evolutionary relationship with society and ecosystems. Business organizations face highly diverse risks which they have to recognize, reflect on and handle. Climate change and its impacts clarify the need for managing overall system risk. Research has shown that climate vulnerability of business organizations in the German food industry is characterized by impacts that, in particular, affect business organizations indirectly. Indirect climate change caused impacts are complex, uncertain and characterized by a high degree of unpredictability. They focus on the derived social, ecological, economic and cultural consequences of the direct physical impacts from a worldwide perspective. This paper shows that introducing resilience thinking helps to identify strategic risks and opportunities coping with climate change caused impacts in sense of corporate climate adaptation strategies. Furthermore, it is shown from a strategic management perspective that mitigation is a profound element of long term adaptation strategies.  相似文献   
134.
Bioenergy and biomass-based products offer the greatest new opportunities for diversifying business in the forest cluster. In particular, biorefineries, which can be integrated into the pulp and paper industry, seem to have immense future potential. This article aims to explore the biorefinery concept and related new products and business operations, as well as new business strategies and company models, which are part of the biorefinery value chain. These factors, which contribute to the establishment and success of forest biorefineries, were examined using internet survey responses and compared between Scandinavia, North America and South America. This article looks at the results of the survey - primarily from the Finnish perspective - to help identify competitive advantages upon which successful business operations in the Finnish forest cluster can be built.According to the survey, the outlooks for technical and raw material choices, as well as barriers to biorefinery diffusion, are very similar in all the studied areas. Biorefineries and related energy products are considered the way to sustainably guarantee the forest cluster’s success. An increase in the price of oil motivates the development of forest biorefineries and wood-based biofuels; however, it is obvious that there is a need to revaluate from a fresh perspective the utilisation of wood and the wood-refining chain in the forest cluster.The survey respondents consider wood-based biofuel and chemical production a serious business opportunity for the forest cluster. In Finland, there is a strong confidence in the production of biofuels. However, all the countries included in the study trust in their own national strengths and in their chance to be a leading actor in the forest biorefinery business worldwide. The forest biorefinery business seems to have market potential, and global competition can thus be expected.  相似文献   
135.
Tumble dryers sold on the market today are labelled according to their energy efficiency. This labelling system has primarily two purposes: to guide buyers to a product with low energy use, lower cost and lower environmental impact and to encourage producers to develop even more energy-efficient products. Tumble dryers are optimized for their maximum capacity, which is used as the standard load for determining the energy label. Three different tumble dryers have been tested with different drying loads. Results indicate that all the tested tumble dryers have significantly lower energy efficiency when drying small loads. In order to encourage the development of tumble dryers with high energy efficiency at drying loads used in ordinary households, the standards for the energy labelling system should be revised.  相似文献   
136.
Industrial symbioses (ISs) and eco-industrial parks (EIPs) are key concepts of industrial ecology (IE). The aim of ISs and EIPs is to minimise inefficient material and energy use by utilising local by-product and energy flows. Industrial symbioses tend to develop through spontaneous action of economic actors, for gaining of economic benefit, but these systems can be designed and promoted via policy instruments as well. A literature review showed that national programmes for eco-industrial parks can be found in different parts of the world. In the action programmes and other sustainable consumption and production (SCP) policy documents of the EU, on the other hand, industrial symbioses gain less recognition as a path to enhanced sustainable production. In this article, we consider this and also analyse how the evolution and environmental performance of an industrial symbiosis system centred on a Finnish pulp and paper mill have been affected by SCP policy instruments. With regard to the system forming the subject of the case study, and Finnish industrial systems in general, policy instruments have succeeded in reducing emissions but not in systematically encouraging operators toward symbiosis-like activities. All in all, few studies exist on the overall impact of policy instruments promoting design of eco-industrial parks. It is not self-evident that symbiosis-like production systems would be sustainable in every case, as the background assumptions for political promotion of EIPs suggest. We concluded that industrial symbioses should be analysed and developed on a life cycle basis, with documentation of the real environmental benefits due to efficient resource use and decreased emissions in comparison to standalone production. ISs can then bring eco-competitiveness to companies in relation to SCP tools, such as environmental permits, ecolabels, and future product regulation based on the Ecodesign Directive in Europe. Indirect encouragement of symbiosis through land-use regulation and planning, in such a way that material fluxes between companies are possible both in operations and in financial terms, may prove effective. The same holds for waste policies that encourage increased reuse of a company’s waste by other enterprises.  相似文献   
137.

Introduction

Fall-related occupational injuries and fatalities are serious problems in the U.S. construction industry, especially incidents related to unguarded holes. The National Institute for Occupational Safety and Health, Division of Safety Research, Morgantown, WV conducted a project to evaluate the effectiveness of guardrail systems to prevent falls through roof and floor holes.

Methods

Two commercial edge-protection products were evaluated when used as perimeter guarding around a roof hole. Installations of the commercial products were compared to job-built guardrails constructed of 2 × 4 construction-grade lumber. Occupational Safety and Health Administration (OSHA) regulations require that “a force of at least 200 pounds” must be supported by the top rail of a guardrail system “in any outward or downward direction at any point along the top edge.” A laboratory testing system was developed to evaluate this requirement. A dynamic 200-lb force was generated against the top rail using a weighted manikin mounted on a hinged steel frame. Nine construction workers, who served as test subjects, each built five different guardrail configurations.

Results

All 45 configurations met the 200-lb OSHA requirement. Installation time for one commercial product was 32% quicker than the job-built configuration (25.6 min vs. 37.9 min).

Impact on Industry

This study: (a) indicates that the two edge-protection products can be used as perimeter guarding; (b) highlights the importance of using proper materials and fasteners to construct guardrails to protect workers from falling into unguarded roof and floor holes; and (c) discusses an overall-strength-testing methodology that can be used by fall-protection researchers.  相似文献   
138.

Problem

Drilling overhead into concrete or metal ceilings is a strenuous task done by construction workers to hang ductwork, piping, and electrical equipment. The task is associated with upper body pain and musculoskeletal disorders. Previously, we described a field usability evaluation of a foot lever and inverted drill press intervention devices that were compared to the usual method for overhead drilling. Both interventions were rated as inferior to the usual method based on poor setup time and mobility.

Method

Three new interventions, which differed on the design used for aligning the drilling column to vertical, were compared to the usual method for overhead drilling by commercial construction workers (n = 16).

Results

The usual method was associated with the highest levels of regional body fatigue and the poorest usability ratings when compared to the three interventions.

Conclusion

Overall, the 'Collar Base' intervention design received the best usability ratings.

Impact on Industry

Intervention designs developed for overhead drilling may reduce shoulder fatigue and prevent subsequent musculoskeletal disorders. These designs may also be useful for other overhead work such as lifting and supporting materials (e.g., piping, ducts) that are installed near the ceiling. Workplace health and safety interventions may require multiple rounds of field-testing prior to achieving acceptable usability ratings by the end users.  相似文献   
139.

Problem

Construction workers suffer the most electrocutions among all industries. Currently, there are no electrical contact warning devices on the market to protect workers. This paper proposes a worker-worn electric-field sensor. As the worker is in proximity to, or in contact with, a live power-circuit, the sensor sets off an audible/visual warning alarm. The sensor also has the potential to wirelessly trip a wireless-capable circuit breaker, and to trigger a wireless transmitter to notify emergency response of an electrical contact.

Methods

An experiment was conducted to measure electric-field variation on simulated human-wrists (10 defrosted hog-legs) in various proximities and in electrical-contact to a simulated power-circuit. The purpose of these tests was to determine the feasibility of developing a worker-worn electric-field detection sensor for use in protecting workers from contact with energized electrical conductors.

Results

This study observed a significant electric-field-magnitude increase as a hog-leg approaches the live-circuit, and the distinct electric-field-magnitude jump as the leg contacts with the live-circuit. The observation indicates that this sensor can be an effective device to warn the workers of electrical hazards. Additionally, the sensor has the potential to wirelessly trip a wireless-capable circuit-breaker and trigger a wireless transmitter (such as a cell phone) to notify an emergency response. The prompt notification prevents the worker from further injury caused by postponed medical-care.

Impact on Industry

Widespread use of this sensor could lower electrocution and electrically related injury rates in the construction industry.  相似文献   
140.

Problem

Nail guns are a common source of acute, and potentially serious, injury in residential construction.

Method

Data on nail gun injuries, hours worked and hours of tool use were collected in 2008 from union apprentice carpenters (n = 464) through classroom surveys; this completed four years of serial cross-sectional data collection from apprentices. A predictive model of injury risk was constructed using Poisson regression.

Results

Injury rates declined 55% from baseline measures in 2005 with early training and increased use of tools with sequential actuation. Injury rates declined among users of tools with both actuation systems, but the rates of injury were consistently twice as high among those using tools with contact trip triggers.

Discussion and impact

Nail gun injuries can be reduced markedly through early training and use of tools with sequential actuation. These successful efforts need to be diffused broadly, including to the non-union sector.  相似文献   
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