909 resultados para Environmental performance
Resumo:
Brazil is doing a major effort to find alternatives to diesel oil as combustible. Some study lines are oriented to the development of vegetable oils used as fuel, as a source of getting cheaper and have higher energy density than the converted vegetable oils, and less risk of environmental contamination. The aim of this study was to evaluate the performance, the useful life of the lubricant and some components of a Diesel Cycle engine, with an electronic injection system, in a long-term test operating with a preheated blend (65°C) of 50% (v v-1) of soybean oil in petrodiesel. There was a reduction of the useful life of the injectors which presented failure because of high wear with 264 hours of operation and showed an increase in emissions of particulate matter (opacity) which may be assigned to the failures occurred in the injection system. An increase in the useful life of the lubricant, when compared with the literature was also observed. The electronic injection system may favor the burning of the tested fuel. The test was interrupted with 264 hours because of failures in the injection system.
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This work presents the implementation and comparison of three different techniques of three-dimensional computer vision as follows: • Stereo vision - correlation between two 2D images • Sensorial fusion - use of different sensors: camera 2D + ultrasound sensor (1D); • Structured light The computer vision techniques herein presented took into consideration the following characteristics: • Computational effort ( elapsed time for obtain the 3D information); • Influence of environmental conditions (noise due to a non uniform lighting, overlighting and shades); • The cost of the infrastructure for each technique; • Analysis of uncertainties, precision and accuracy. The option of using the Matlab software, version 5.1, for algorithm implementation of the three techniques was due to the simplicity of their commands, programming and debugging. Besides, this software is well known and used by the academic community, allowing the results of this work to be obtained and verified. Examples of three-dimensional vision applied to robotic assembling tasks ("pick-and-place") are presented.
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The global concern about sustainability has been growing and the mining industry is questioned about its environmental and social performance. Corporate social responsibility (CSR) is an important issue for the extractive industries. The main objective of this study was to investigate the relationship between CSR performance and financial performance of selected mining companies. The study was conducted by identifying and comparing a selection of available CSR performance indicators with financial performance indicators. Based on the result of the study, the relationship between CSR performance and financial performance is unclear for the selected group of companies. The result is mixed and no industry specific realistic way to measure CSR performance uniformly is available. The result as a whole is contradictory and varies at company level as well as based on the selected indicators. The result of this study confirms that the relationship between CSR performance and financial performance is complicated and difficult to determine. As an outcome, evaluation of benefits of CSR in the mining sector could better be analyzed based on different attributes.
Resumo:
This study is a part of the Ecologically Friendly Port Ust-Luga (EFP) project. The purpose of this study is to examine the environmental status of the Finnish ports and, more specifically, the Port of HaminaKotka. An analysis of the environmental status is performed mainly as a literature review, because the Finnish ports must comply with Finnish and EU legislation and with the binding international regulations and conventions created by different organizations. The International Maritime Organisation (IMO) has done groundbreaking work in the field of maritime safety and maritime environmental protection. The MARPOL convention has a great impact on decreasing pollution from international shipping and it applies to 99% of the world’s merchant tonnage. Pollution prevention covers: Oil pollution, Chemical pollution, Air pollution and GHG Emissions, Dumping of Wasted and Other Matters, Garbage, Sewage, Port Reception Facilities, Special Areas under MARPOL and Particularly Sensitive Sea Areas. There is also Pollution Prevention for other treaties like anti-fouling systems used on ships, the transfer of alien species by ships’ ballast water and the environmentally sound recycling of ships. There are more than twenty different EU and international regulations that influence ports and port operations in Finland. In addition, there is also national legislation that has an effect on Finnish ports. For the most part, the legislation for ports is common in the EU area, but the biggest and most important difference between the legislation in Finland and other EU countries is due to the Act on Environmental Impact Assessment Procedure. The Act states that the environmental impact assessment procedure shall be applied to projects that may have significant adverse environmental impacts, due to the special features of Finland`s nature and environment. In this Act, the term environmental impact refers to the direct and indirect effects inside and outside Finnish territory of a project or operations on human health, living conditions and amenity; soil, water, air, climate, organisms, interaction between them and biodiversity; community structure, buildings, landscape, townscape and cultural heritage; utilization of natural resources. In Finland, the Environmental Permit requires that ports collect all necessary information concerning environmental effects and make required reports to the Finnish authorities, stakeholders and the public. Commonly, environmental reporting is public and environmental achievements are emphasized in reporting and in media. At the moment, the problem in environmental reporting is that it’s difficult to compare data from different ports. There is enough data concerning the environmental effects and performance, but the manner of reporting and the quality of the data varies between ports. There are differences in the units and codes used, in some cases the information is not sufficient and it can even be rather unreliable. There are also differences regarding the subjects that are emphasized in reporting.
Resumo:
The performance measurement produces information about the operation of the business process. On the basis of this information performance of the company can be followed and improved. Balanced performance measurement system can monitor performance of several perspectives and business processes can be led according to company strategy. Major part of the costs of a company is originated from purchased goods or services are an output of the buying process emphasising the importance of a reliable performance measurement of purchasing process. In the study, theory of balanced performance measurement is orientated and framework of purchasing process performance measurement system is designed. The designed balanced performance measurement system of purchasing process is tested in case company paying attention to the available data and to other environmental enablers. The balanced purchasing performance measurement system is tested and improved during the test period and attention is paid to the definition and scaling of objectives. Found development initiatives are carried out especially in the scaling of indicators. Finally results of the study are evaluated, conclusions and additional research areas proposed.
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Sales and operations research publications have increased significantly in the last decades. The concept of sales and operations planning (S&OP) has gained increased recognition and has been put forward as the area within Supply Chain Management (SCM). Development of S&OP is based on the need for determining future actions, both for sales and operations, since off-shoring, outsourcing, complex supply chains and extended lead times make challenges for responding to changes in the marketplace when they occur. Order intake of the case company has grown rapidly during the last years. Along with the growth, new challenges considering data management and information flow have arisen due to increasing customer orders. To manage these challenges, case company has implemented S&OP process, though initial process is in early stage and due to this, the process is not managing the increased customer orders adequately. Thesis objective is to explore extensively the S&OP process content of the case company and give further recommendations. Objectives are categorized into six different groups, to clarify the purpose of this thesis. Qualitative research methods used are active participant observation, qualitative interviews, enquiry, education, and a workshop. It is notable that demand planning was felt as cumbersome, so it is typically the biggest challenge in S&OP process. More proactive the sales forecasting can be, more expanded the time horizon of operational planning will turn out. S&OP process is 60 percent change management, 30 percent process development and 10 percent technology. The change management and continuous improvement can sometimes be arduous and set as secondary. It is important that different people are required to improve the process and the process is constantly evaluated. As well as, process governance is substantially in a central role and it has to be managed consciously. Generally, S&OP process was seen important and all the stakeholders were committed to the process. Particular sections were experienced more important than others, depending on the stakeholders’ point of views. Recommendations to objective groups are evaluated by the achievable benefit and resource requirement. The urgent and easily implemented improvement recommendations should be executed firstly. Next steps are to develop more coherent process structure and refine cost awareness. Afterwards demand planning, supply planning, and reporting should be developed more profoundly. For last, information technology system should be implemented to support the process phases.
Resumo:
The main objective of this thesis is to evaluate the economic and environmental effectiveness of three different renewable energy systems: solar PV, wind energy and biomass energy systems. Financial methods such as Internal Rate of Return (IRR) and Modified Internal Rate of Return (MIRR) were used to evaluate economic competitiveness. Seasonal variability in power generation capability of different renewable systems were also taken into consideration. In order to evaluate the environmental effectiveness of different energy systems, default values in GaBi software were taken by defining the functional unit as 1kWh. The results show that solar PV systems are difficult to justify both in economic as well as environmental grounds. Wind energy performs better in both economic and environmental grounds and has the capability to compete with conventional energy systems. Biomass energy systems exhibit environmental and economic performance at the middle level. In each of these systems, results vary.
Resumo:
Several automated reversed-phase HPLC methods have been developed to determine trace concentrations of carbamate pesticides (which are of concern in Ontario environmental samples) in water by utilizing two solid sorbent extraction techniques. One of the methods is known as on-line pre-concentration'. This technique involves passing 100 milliliters of sample water through a 3 cm pre-column, packed with 5 micron ODS sorbent, at flow rates varying from 5-10 mUmin. By the use of a valve apparatus, the HPLC system is then switched to a gradient mobile phase program consisting of acetonitrile and water. The analytes, Propoxur, Carbofuran, Carbaryl, Propham, Captan, Chloropropham, Barban, and Butylate, which are pre-concentrated on the pre-column, are eluted and separated on a 25 cm C-8 analytical column and determined by UV absorption at 220 nm. The total analytical time is 60 minutes, and the pre-column can be used repeatedly for the analysis of as many as thirty samples. The method is highly sensitive as 100 percent of the analytes present in the sample can be injected into the HPLC. No breakthrough of any of the analytes was observed and the minimum detectable concentrations range from 10 to 480 ng/L. The developed method is totally automated for the analysis of one sample. When the above mobile phase is modified with a buffer solution, Aminocarb, Benomyl, and its degradation product, MBC, can also be detected along with the above pesticides with baseline resolution for all of the analytes. The method can also be easily modified to determine Benomyl and MBC both as solute and as particulate matter. By using a commercially available solid phase extraction cartridge, in lieu of a pre-column, for the extraction and concentration of analytes, a completely automated method has been developed with the aid of the Waters Millilab Workstation. Sample water is loaded at 10 mL/min through a cartridge and the concentrated analytes are eluted from the sorbent with acetonitrile. The resulting eluate is blown-down under nitrogen, made up to volume with water, and injected into the HPLC. The total analytical time is 90 minutes. Fifty percent of the analytes present in the sample can be injected into the HPLC, and recoveries for the above eight pesticides ranged from 84 to 93 percent. The minimum detectable concentrations range from 20 to 960 ng/L. The developed method is totally automated for the analysis of up to thirty consecutive samples. The method has proven to be applicable to both purer water samples as well as untreated lake water samples.
Resumo:
Les troubles reliés à la dépression, l’épuisement professionnel et l’anxiété sont de plus en plus répandus dans notre société moderne. La consommation croissante d’antidépresseurs dans les différents pays du monde est responsable de la récente détection de résidus à l’état de traces dans les rejets urbains municipaux. Ainsi, ces substances dites « émergentes » qui possèdent une activité pharmacologique destinée à la régulation de certains neurotransmetteurs dans le cerveau suscitent maintenant de nombreuses inquiétudes de la part de la communauté scientifique. L’objectif principal de ce projet de doctorat a été de mieux comprendre le devenir de plusieurs classes d’antidépresseurs présents dans diverses matrices environnementales (i.e. eaux de surfaces, eaux usées, boues de traitement, tissus biologiques) en développant de nouvelles méthodes analytiques fiables capables de les détecter, quantifier et confirmer par chromatographie liquide à haute performance couplée à la spectrométrie de masse en tandem (LC-QqQMS, LC-QqToFMS). Une première étude complétée à la station d’épuration de la ville de Montréal a permis de confirmer la présence de six antidépresseurs et quatre métabolites N-desmethyl dans les affluents (2 - 330 ng L-1). Pour ce traitement primaire (physico-chimique), de faibles taux d’enlèvement (≤ 15%) ont été obtenus. Des concentrations d’antidépresseurs atteignant près de 100 ng L-1 ont également été détectées dans le fleuve St-Laurent à 0.5 km du point de rejet de la station d’épuration. Une seconde étude menée à la même station a permis l’extraction sélective d’antidépresseurs dans trois tissus (i.e. foie, cerveau et filet) de truites mouchetées juvéniles exposées à différentes concentrations d’effluent dilué traité et non-traité à l’ozone. Un certain potentiel de bioaccumulation dans les tissus (0.08-10 ng g-1) a été observé pour les spécimens exposés à l’effluent non-traité (20% v/v) avec distribution majoritaire dans le foie et le cerveau. Une intéressante corrélation a été établie entre les concentrations de trois antidépresseurs dans le cerveau et l’activité d’un biomarqueur d’exposition (i.e. pompe N/K ATPase impliquée dans la régulation de la sérotonine) mesurée à partir de synaptosomes de truites exposées aux effluents. Une investigation de l’efficacité de plusieurs stations d’épuration canadiennes opérant différents types de traitements a permis de constater que les traitements secondaires (biologiques) étaient plus performants que ceux primaires (physico-chimiques) pour enlever les antidépresseurs (taux moyen d’enlèvement : 30%). Les teneurs les plus élevées dans les boues traitées (biosolides) ont été obtenues avec le citalopram (1033 ng g-1), la venlafaxine (833 ng g-1) et l’amitriptyline (78 ng g-1). Des coefficients de sorption expérimentaux (Kd) calculés pour chacun des antidépresseurs ont permis d’estimer une grande sorption des composés sertraline, desméthylsertraline, paroxetine et fluoxetine sur les solides (log Kd > 4). Finalement, un excellent taux d’enlèvement moyen de 88% a été obtenu après ozonation (5 mg L-1) d’un effluent primaire. Toutefois, la caractérisation de nouveaux sous-produits N-oxyde (venlafaxine, desmethylvenlafaxine) par spectrométrie de masse à haute résolution (LC-QqToFMS) dans l’effluent traité à l’ozone a mis en lumière la possibilité de formation de multiples composés polaires de toxicité inconnue.
Resumo:
Paper industry is one of the oldest and largest industries in Kerala. Despite the developments in the industry in terms of growth in output , value added and employment generation, many of the units face grave problems. Irrespective of the size of the plant, the problems of the industry are general in nature. The problems are galore in the supply, not the demand side. Amomg the problems, the important ones are: raw material scarcity, energy deficiency and obsolete technology. Further, the industry is subject to many controls by the Government — price control, product control and raw materials control — which result in the dwindling of profits and investments. Equally important are the reservations against the industry for polluting the environment byeffluent disposal on the one hand and affecting ecological balance by depleting the existing forest on the other. Apart from the large, medium and small pulp and paper mills, there are about 30 hand made paper units in Kerala which can be categorised as village and cottage industry. Almost all of these units began at the initiative and support of Khadi and Village Industries Commission. The primary purpose of these units is employment generation, and not profit making. Currently many of these units are in the red and many others are on the verge of closure. Therefore, a separate analysis of the growth performance, and problems and prospects of the hand made paper industry has also been attempted. It is analysed separately because of the very small size of the hand made paper units
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Els Sistemes d'Aiguamolls Construïts (SAC) de Flux Subsuperficial Horitzontal (FSH) és una tecnologia apropiada pel sanejament d'aigües residuals procedents de nuclis de població petits. No obstant els SAC de FSH són considerats una tecnologia natural, l'operació i manteniment d'aquestes depuradores és crucial per a garantir el seu correcte funcionament. Aquestes necessitats d'operació i manteniment varien entre depuradores segons (1) les característiques de la comunitat, (2) la configuració de la depuradora i el disseny del SAC de FSH i (3) les característiques del medi receptor. En aquest sentit, en aquesta tesi es presenta el desenvolupament d'un Sistema d'Ajuda a la Decisió (SAD) per a la definició de protocols d'operació i manteniment per a SAC de FSH tenint en compte els factors que causen variabilitat entre aquest tipus de depuradores (1, 2 i 3).
Resumo:
Na sequência da integração da energia eólica em larga escala foram estabelecidos códigos de rede pelos vários operadores de sistema, exigindo que os parques eólicos permaneçam em serviço durante e após a ocorrência de defeitos na rede a montante. Nos parques eólicos equipados com sistemas de velocidade constante este requisito pode ser assegurado pela instalação, no ponto de interligação à rede, de equipamento de compensação dinâmica de potência reactiva, controlado como fonte de tensão, sendo as funções de controlo baseadas em medidas efectuadas no ponto de interligação relativamente às componentes directas da tensão e da corrente. Como a adopção deste tipo de soluções externas é adequada ao funcionamento do sistema em regime equilibrado, este artigo foca a avaliação do desempenho da solução no caso da ocorrência de defeitos assimétricos. Os resultados obtidos através das simulações dinâmicas evidenciam o aparecimento de sobre tensões nas fases não afectadas pelo defeito que poderão colocar o parque eólico fora de serviço.
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The study reported presents the findings relating to commercial growing of genetically-modified Bt cotton in South Africa by a large sample of smallholder farmers over three seasons (1998/99, 1999/2000, 2000/01) following adoption. The analysis presents constructs and compares groupwise differences for key variables in Bt v. non-Bt technology and uses regressions to further analyse the production and profit impacts of Bt adoption. Analysis of the distribution of benefits between farmers due to the technology is also presented. In parallel with these socio-economic measures, the toxic loads being presented to the environment following the introduction of Bt cotton are monitored in terms of insecticide active ingredient (ai) and the Biocide Index. The latter adjusts ai to allow for differing persistence and toxicity of insecticides. Results show substantial and significant financial benefits to smallholder cotton growers of adopting Bt cotton over three seasons in terms of increased yields, lower insecticide spray costs and higher gross margins. This includes one particularly wet, poor growing season. In addition, those with the smaller holdings appeared to benefit proportionately more from the technology (in terms of higher gross margins) than those with larger holdings. Analysis using the Gini-coefficient suggests that the Bt technology has helped to reduce inequality amongst smallholder cotton growers in Makhathini compared to what may have been the position if they had grown conventional cotton. However, while Bt growers applied lower amounts of insecticide and had lower Biocide Indices (per ha) than growers of non-Bt cotton, some of this advantage was due to a reduction in non-bollworm insecticide. Indeed, the Biocide Index for all farmers in the population actually increased with the introduction of Bt cotton. The results indicate the complexity of such studies on the socio-economic and environmental impacts of GM varieties in the developing world.
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This paper deconstructs the relationship between the Environmental Sustainability Index (ESI) and national income. The ESI attempts to provide a single figure which encapsulates environmental sustainability' for each country included in the analysis, and this allied with a 'league table' format so as to name and shame bad performers, has resulted in widespread reporting within the popular presses of a number of countries. In essence, the higher the value of the ESI then the more 'environmentally sustainable' a country is deemed to be. A logical progression beyond the use of the ESI to publicise environmental sustainability is its use within a more analytical context. Thus an index designed to simplify in order to have an impact on policy is used to try and understand causes of good and bad performance in environmental sustainability. For example the creators of the ESI claim that ESI is related to GDP/capita (adjusted for Purchasing Power Parity) such that the ESI increases linearly with wealth. While this may in a sense be a comforting picture, do the variables within the ESI allow for alternatives to the story, and if they do then what are the repercussions for those producing such indices for broad consumption amongst the policy makers, mangers, the press, etc.? The latter point is especially important given the appetite for such indices amongst non-specialists, and for all their weaknesses the ESI and other such aggregated indices will not go away. (C) 2007 Elsevier Ltd. All rights reserved.
Resumo:
The performance of the atmospheric component of the new Hadley Centre Global Environmental Model (HadGEM1) is assessed in terms of its ability to represent a selection of key aspects of variability in the Tropics and extratropics. These include midlatitude storm tracks and blocking activity, synoptic variability over Europe, and the North Atlantic Oscillation together with tropical convection, the Madden-Julian oscillation, and the Asian summer monsoon. Comparisons with the previous model, the Third Hadley Centre Coupled Ocean-Atmosphere GCM (HadCM3), demonstrate that there has been a considerable increase in the transient eddy kinetic energy (EKE), bringing HadGEM1 into closer agreement with current reanalyses. This increase in EKE results from the increased horizontal resolution and, in combination with the improved physical parameterizations, leads to improvements in the representation of Northern Hemisphere storm tracks and blocking. The simulation of synoptic weather regimes over Europe is also greatly improved compared to HadCM3, again due to both increased resolution and other model developments. The variability of convection in the equatorial region is generally stronger and closer to observations than in HadCM3. There is, however, still limited convective variance coincident with several of the observed equatorial wave modes. Simulation of the Madden-Julian oscillation is improved in HadGEM1: both the activity and interannual variability are increased and the eastward propagation, although slower than observed, is much better simulated. While some aspects of the climatology of the Asian summer monsoon are improved in HadGEM1, the upper-level winds are too weak and the simulation of precipitation deteriorates. The dominant modes of monsoon interannual variability are similar in the two models, although in HadCM3 this is linked to SST forcing, while in HadGEM1 internal variability dominates. Overall, analysis of the phenomena considered here indicates that HadGEM1 performs well and, in many important respects, improves upon HadCM3. Together with the improved representation of the mean climate, this improvement in the simulation of atmospheric variability suggests that HadGEM1 provides a sound basis for future studies of climate and climate change.