102 resultados para combustione biomasse materiale particolato (PM) idrocarburi policiclici aromatici (IPA) stufe a pellet


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Management of project knowledge is a critical factor for project success. Project Management Office (PMO) is a unit within organisations to centrally facilitate, manage and control organisational project for improving the rate of project success. Due to increasing interest of developing PMO, the Project Management Maturity Model (PMMM) has been proposed to develop PMOs gradually. The PMMM contributes to evolvement of PMO from immature to mature level through addressing appropriate PM practices. Despite the importance of project knowledge, it has not been extensively investigated in project environments. In addition, the existing PMMMs not only do not address management of project knowledge, but also they recommend little criteria to assess the maturity of PMO from KM point of view. The absence of KM discussion in current PMMMs was defined as the subject of a research project in order for addressing KM practices at various maturity levels of PMO. In order to address the mentioned gap, a framework has been developed based on the current discussions of both PM and KM. The proposed framework comprises three premises: KM processes and practices, PMMM, and KM Maturity Model (KMMM). The incorporation of KMMM practices at various maturity levels of PMO is one of the significance of this framework. It proposes numbers of KM strategies, processes, and practices to address project knowledge management at various levels PMO. This framework shall be useful guidance for developing PMOs from KM perspective. In other words, it contributes to management of project knowledge, as a key for project success. The proposed framework follows the process-based approach and it could be employed alongside the current PMMMs for PMO development. This paper presents the developed framework, theoretical background, premises, proposed KM practices, and processes to be employed in Project-based Organisations and PMOs. This framework has been examined at numbers of case studies with different maturity levels. The case studies outcomes, which will be subjects for future papers, have not shown any significant contradiction yet, however, more investigations are being conducted to validate the proposed framework.

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Knowledge Management (KM) is vital factor to successfully undertake projects. The temporary nature of projects necessitates employing useful KM practices to reduce any issues such as knowledge leakiness and rework. The Project Management Office (PMO) is a unit within organisations to facilitate and oversee organisational projects. Project Management Maturity Models (PMMM) show the development of PMOs from immature to mature levels. The existing PMMMs have focused on discussing Project Management (PM) practices, however, the management of project knowledge is yet to be addressed, at various levels of maturity. A research project was undertaken to investigate the mentioned gap for addressing KM practices at the existing PMMMs. Due to the exploratory and inductive nature of this research, qualitative methods using case studies were chosen as the research methodology to investigate the problem in the real world. In total, three cases selected from different industries: research; mining and government organisations, to provide broad categories for research and research questions were examined using the developed framework. This paper presents the findings from the investigation of the research organisation with the lowest level of maturity. From KM process point of view, knowledge creation and capturing are the most important processes, while knowledge transferring and reusing received less attention. In addition, it was revealed that provision of “knowledge about client” and “project management knowledge” are the most important types of knowledge that are required at this level of maturity. The results also revealed that PMOs with higher maturity level have better knowledge management, however, some improvement is needed. In addition, the importance of KM processes varies at different levels of maturity. In conclusion, the outcomes of this paper could provide powerful guidance to PMOs at lowest level of maturity from KM point of view.

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It has been well established that organic compounds with adjacent hydroxyl groups in Bayer process liquor can inhibit gibbsite precipitation by acting as seed poisons. The degree of inhibition is a function of the number and stereochemistry of the hydroxyl groups. Seed poisons generally adsorb strongly onto hydrate surfaces, implying that surface coverage is the mechanism for yield inhibition. There are examples however of organics that strongly adsorb but do not lead to yield inhibition. There is a possibility that this apparent contradiction may be an artifact of differences in conditions between the adsorption and precipitation experiments. The present work investigates the adsorption and inhibition effects of a range of compounds under strictly similar conditions to clarify the role of adsorption on yield inhibition.

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Cluster ions and charged and neutral nanoparticle concentrations were monitored using a neutral cluster and air ion spectrometer (NAIS) over a period of one year in Brisbane, Australia. The study yielded 242 complete days of usable data, of which particle formation events were observed on 101 days. Small, intermediate and large ion concentrations were evaluated in real time. In the diurnal cycle, small ion concentration was highest during the second half of the night while large ion concentrations were a maximum during the day. The small ion concentration showed a decrease when the large ion concentration increased. Particle formation was generally followed by a peak in the intermediate ion concentration. The rate of increase of intermediate ions was used as the criteria for identifying particle formation events. Such events were followed by a period of growth to larger sizes and usually occurred between 8 am and 2 pm. Particle formation events were found to be related to the wind direction. The gaseous precursors for the production of secondary particles in the urban environment of Brisbane have been shown to be ammonia and sulfuric acid. During these events, the nanoparticle number concentrations in the size range 1.6 to 42 nm, which were normally lower than 1x104 cm-3, often exceeded 5x104 cm-3 with occasional values over 1x105 cm-3. Cluster ions generally occurred in number concentrations between 300 and 600 cm-3 but decreased significantly to about 200 cm-3 during particle formation events. This was accompanied by an increase in the large ion concentration. We calculated the fraction of nanoparticles that were charged and investigated the occurrence of possible overcharging during particle formation events. Overcharging is defined as the condition where the charged fraction of particles is higher than in charge equilibrium. This can occur when cluster ions attach to neutral particles in the atmosphere, giving rise to larger concentrations of charged particles in the short term. Ion-induced nucleation is one of the mechanisms of particle formation in the atmosphere, and overcharging has previously been considered as an indicator of this process. The possible role of ions in particle formation was investigated.

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Thin film nanostructured gas sensors typically operate at temperatures above 400°C, but lower temperature operation is highly desirable, especially for remote area field sensing as this reduces significantly power consumption. We have investigated a range of sensor materials based on both pure and doped tungsten oxide (mainly focusing on Fe-doping), deposited using both thermal evaporation and electron-beam evaporation, and using a variety of post-deposition annealing. The films show excellent sensitivity at operating temperatures as low as 150°C for detection of NO2. There is a definite relationship between the sensitivity and the crystallinity and nanostructure obtained through the deposition and heat treatment processes, as well as variations in the conductivity caused both by doping and heat treatmetn. The ultimate goal of this work is to control the sensing properties, including selectivity to specific gases through the engineering of the electronic properties and the nanostructure of the films.

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Data was collected to measure shopper’s attitudes toward the proposed Sunday and limited public holiday trading in Dalby. Survey questionnaires were conducted between 29th August to 31st August at Coles Dalby and Dalby Shoppingtown Plaza. In total, 150 respondents participated in the survey. Overall, the findings suggest that most respondents, especially males, couples with children, fulltime workers and those under the age of 49 years, embrace the proposed Sunday and limited holiday trading in Dalby. While there are concerns over increasing competition for smaller retailers who already trade on Sundays, a majority of respondents indicated it would suit their lifestyle, be convenient, provide more jobs, increase trade for smaller retailers within the area, reduce queues and congestion observed on Saturdays. The majority of those shoppers that indicated they currently did some shopping on a Sunday reported they would continue to support smaller retailers who currently trade on Sundays and some public holidays, if changes came about. Those opposed to changes to trading hours indicated a belief that existing trading hours were sufficient. Most people indicated the proposed extension of trading hours would not harm the community or have a negative, detrimental effect on themselves or their family. The main findings presented in the report are as follows: - 96.8% of respondents surveyed reported to be local, permanent residents of Dalby. - Residents of Dalby visited shopping centres and stores on average 2.8 times per week. This frequency is proportionately higher than the average Australian shopping behaviour at 2.5 times per week (Roy Morgan Supermarket Monitor). - It was determined that weekday evenings (after 5 pm) were the busiest times for shopping, with Saturday the next most popular day to shop. - 68% of respondents support the proposal of the extended trading hours at supermarkets, department stores and the shopping centre in Dalby, 26% oppose and 6% are unsure. - 90% of the respondents agreed that residents of Dalby should be allowed the same choice as other regional towns and cities in supporting/opposing changes to trading hours. The remaining 10% expressed a disagreement. - A larger percentage of males supported the proposal for Sunday and limited holiday trading. Of all the males surveyed, 80% were in support, 15% were opposed and 5% unsure. 60% of female respondents support the proposal, while 33% oppose it and 5% were unsure. - The highest percentage of support exists in fulltime workers with 90% of those respondents supporting the proposal. - In contrast, the lowest percentage of support was found in the non-working (retired/unemployed) respondents, where 67% opposed the application. - It was noted that 71% of respondents employed casually also indicated opposition against proposed changes. Further questioning identified an underlying concern from casually employed persons that Sunday trade would force them onto Sunday work rosters. - 92% of shared households expressed support for Sunday and limited public holiday trading, while 83% of both couples with children and single parent with children at home also supported the application. - 72% of the respondents often find it necessary to do some grocery shopping in Dalby on a Sunday. 76% of shoppers who indicated they already undertook some shopping on Sunday, indicated would continue to shop and support smaller retailers. - Of the respondents surveyed, 44% have travelled outside of Dalby on a Sunday to shop. This indicates that such residents find it necessary to undertake some shopping on a Sunday and in order to do so, drive an hour to Toowoomba in order to access a range of retailers. - The most cited reasons for supporting Sunday and limited public holiday trade were; ‘More choice about when I shop and that is convenient’ (69%), ‘Sunday trade will create job opportunities’ (71%), ‘Sunday trade will be helpful when preparing school lunches and getting ready for the working week’ (62%), and ‘Sunday trade will reduce shopping congestion during peak shopping periods’ (62%) - The most cited reasons for opposing the proposed changes are that ‘Sunday trade may increase competition for small retailers who already trade on Sunday’ (41%), ‘Shops are already open 6 days a week which is enough’ (31%), and ‘Sunday is a day of rest or a religious day and shopping should not be allowed’ (23%). - 97% of respondents indicated they would not change their sporting or social commitment if changes to trading hours were implemented.

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Objective Lower lipid and insulin levels are found during a glucose-tolerance test in obese black than obese white South African women. Therefore, β-cell function and lipid metabolism were compared in these populations during a mixed meal. Research Methods and Procedures Blood concentrations of glucose, free fatty acids (FFAs), insulin, lipograms, and in vivo FFA oxidation were determined at fasting and for 7 hours after oral administration of a mixed emulsion containing glucose-casein-sucrose-lipid and [1-13C] palmitic acid in 8 lean black women (LBW), 10 obese black women (OBW), 9 lean white women (LWW), and 10 obese white women (OWW). Subcutaneous and visceral fat mass was assessed by computerized tomography. Results Visceral fat area was higher in OWW (152.7 ± 17.0 cm2) than OBW (80.0 ± 6.7 cm2; p < 0.01). In OBW, 30-minute insulin levels were higher (604.3 ± 117.6 pM) than OWW (311.0 ± 42.9 pM; p < 0.05). Total triglyceride was higher in OWW (706.7 ± 96.0 mM × 7 hours) than OBW (465.7 ± 48.2 mM × 7 hours; p < 0.05) and correlated with visceral fat area (β = 0.38, p = 0.05). Palmitate oxidation was higher in lean than obese women in both ethnic groups and correlated negatively with fat mass (β = −0.58, p < 0.005). Discussion The higher 30-minute insulin response in OBW may reflect a higher insulinotropic effect of FFAs or glucose. The elevated triglyceride level of OWW may be due to their higher visceral fat mass and possibly reduced clearance by adipose tissue.

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We have developed a new protein microarray (Immuno-Flow Protein Platform, IFPP) that utilizes a porous nitrocellulose (NC) membrane with printed spots of capture probes. The sample is pumped actively through the NC membrane, to enhance binding efficiency and introduce stringency. Compared to protein microarrays assayed with the conventional incubation-shaking method the rate of binding is enhanced on the IFPP by at least a factor of 10, so that the total assay time can be reduced drastically without compromising sensitivity. Similarly, the sensitivity can be improved. We demonstrate the detection of 1 pM of C-reactive protein (CRP) in 70 mu L of plasma within a total assay time of 7 min. The small sample and reagent volumes, combined with the speed of the assay, make our IFPP also well-suited for a point-of-care/near-patient setting. The potential clinical application of the IFPP is demonstrated by validating CRP detection both in human plasma and serum samples against standard clinical laboratory methods.

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City centres have large volumes of pedestrians and motorised traffic and increases in walking and cycling could potentially lead to more pedestrians and cyclists being injured. In this study, observers recorded cyclist characteristics, number of pedestrians within 1m and 5m radius and type of conflict (none, pedestrian, vehicle) for 1,971 cyclists in 2010 and 2,551 cyclists in 2012 at six locations in the Brisbane Central Business District. Only 1.7% of cyclists were involved in conflicts with a motor vehicle or pedestrian and no collisions were observed. Increased odds of a pedestrian-cyclist conflict was associated with: male riders, riders not wearing correctly fastened helmets, riding on the footpath, higher pedestrian density (within 1m but not within 5m), morning peak and 2-4 pm (compared with 4-6 pm), two-way roads, roads with more lanes, higher speed limits, and yellow marked bicycle symbols on the road.

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Several cell-free assays are currently used to quantify and detect the Reactive Oxygen Species (ROS). All of them have certain limitations, do not provide direct comparison of results and, to date, none of these assays have been acknowledged as the most suitable acellular assay and none has yet been adopted for investigation of potential PM toxicity. These assays include DTT, ascorbic acid, DCFHDA and PFN assays which have been used in measurements of the particles generated from various combustion sources such as diesel engine, wood smoke (or biomass burning) and cigarette smoke, as well as for outdoor measurements. All the probes use different units for expressing redox properties of PM. Also, their reactivity is being triggered by different types of ROS. This limits the direct comparison of the results that are reporting the toxicity of the same aerosol type measured with various probes. This study is evaluating and comparing the various assays in order to develop deeper understanding of their capabilities, selectivity as well as improve understanding of the underlying chemical mechanisms. Keywords: DTT, DCFH-DA, PFN, BPEA-nit, Ascorbic acid, oxidative potential

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Knowledge Management (KM) is vital factor to successfully undertake projects. The temporary nature of projects necessitates employing useful KM practices for tackling issues such as knowledge leakiness and rework. The Project Management Office (PMO) is a unit within organizations to facilitate and oversee organizational projects. Project Management Maturity Models (PMMM) shows the development of PMOs from immature to mature levels. The existing PMMMs have focused on discussing Project Management (PM) practices, however, the management of project knowledge is yet to be addressed, at various levels of maturity. This research project was undertaken to investigate the mentioned gap for addressing KM practices at the existing PMMMs. Due to the exploratory and inductive nature of this research, qualitative methods were chosen as the research methodology. In total, three cases selected from different industries: research; mining and government organizations, to provide broad categories for research and research questions were examined using the developed framework. This paper presents the partial findings of undertaken investigation of the research organisation with the lowest level of maturity. The result shows that knowledge creation and capturing are the most important processes, while knowledge transferring and reusing are not as important as the other two processes. In addition, it was revealed that provision of “knowledge about client” and “project management knowledge” are the most important types of knowledge that are required at this level of maturity. In conclusion, the outcomes of this paper shall provide powerful guidance to PMOs at lowest level of maturity from KM point of view.

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Objectives To quantify the mortality burden attributed to urban outdoor air pollution in South Africa in 2000. Design The study followed comparative risk assessment (CRA) methodology developed by the World Heath Organization (WHO). In most urban areas, annual mean concentrations of particulate matter (PM) with diameters less than 10 μum (PM10) from monitoring network data and PM with diameters less than 2.5 μm (PM2.5) derived using a ratio method were weighted according to population size. PM10 and PM2.5 data from air-quality assessment studies in areas not covered by the network were also included. Population-attributable fractions calculated using risk coefficients presented in the WHO study were weighted by the proportion of the total population (33%) in urban environments, and applied to revised estimates of deaths and years of life lost (YLLs) for South Africa in 2000. Setting South Africa. Subjects Children under 5 years and adults 30 years and older. Outcome measures Mortality and YLLs from lung cancer and cardiopulmonary disease in adults (30 years and older), and from acute respiratory infections (ARIs) in children aged 0 - 4 years. Results Outdoor air pollution in urban areas in South Africa was estimated to cause 3.7% of the national mortality from cardiopulmonary disease and 5.1% of mortality attributable to cancers of the trachea, bronchus and lung in adults aged 30 years and older, and 1.1% of mortality from ARIs in children under 5 years of age. This amounts to 4 637 or 0.9% (95% uncertainty interval 0.3 - 1.5%) of all deaths and about 42 000 YLLs, or 0.4% (95% uncertainty interval 0.1 - 0.7%) of all YLLs in persons in South Africa in 2000. Conclusion Urban air pollution has under-recognised public health impacts in South Africa. Fossil fuel combustion emissions and traffic-related air pollution remain key targets for public health in South Africa.

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Non-thermal plasma (NTP) is a promising candidate for controlling engine exhaust emissions. Plasma is known as the fourth state of matter, where both electrons and positive ions co-exist. Both gaseous and particle emissions of diesel exhaust undergo chemical changes when they are exposed to plasma. In this project diesel particulate matter (DPM) mitigation from the actual diesel exhaust by using NTP technology has been studied. The effect of plasma, not only on PM mass but also on PM size distribution, physico-chemical structure of PM and PM removal mechanisms, has been investigated. It was found that NTP technology can significantly reduce both PM mass and number. However, under some circumstances particles can be formed by nucleation. Energy required to create the plasma with the current technology is higher than the benchmark set by the commonly used by the automotive industry. Further research will enable the mechanism of particle creation and energy consumption to be optimised.

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Linear assets are engineering infrastructure, such as pipelines, railway lines, and electricity cables, which span long distances and can be divided into different segments. Optimal management of such assets is critical for asset owners as they normally involve significant capital investment. Currently, Time Based Preventive Maintenance (TBPM) strategies are commonly used in industry to improve the reliability of such assets, as they are easy to implement compared with reliability or risk-based preventive maintenance strategies. Linear assets are normally of large scale and thus their preventive maintenance is costly. Their owners and maintainers are always seeking to optimize their TBPM outcomes in terms of minimizing total expected costs over a long term involving multiple maintenance cycles. These costs include repair costs, preventive maintenance costs, and production losses. A TBPM strategy defines when Preventive Maintenance (PM) starts, how frequently the PM is conducted and which segments of a linear asset are operated on in each PM action. A number of factors such as required minimal mission time, customer satisfaction, human resources, and acceptable risk levels need to be considered when planning such a strategy. However, in current practice, TBPM decisions are often made based on decision makers’ expertise or industrial historical practice, and lack a systematic analysis of the effects of these factors. To address this issue, here we investigate the characteristics of TBPM of linear assets, and develop an effective multiple criteria decision making approach for determining an optimal TBPM strategy. We develop a recursive optimization equation which makes it possible to evaluate the effect of different maintenance options for linear assets, such as the best partitioning of the asset into segments and the maintenance cost per segment.

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This study is seeking to investigate the effect of non-thermal plasma technology in the abatement of particulate matter (PM) from the actual diesel exhaust. Ozone (O3) strongly promotes PM oxidation, the main product of which is carbon dioxide (CO2). PM oxidation into the less harmful product (CO2) is the main objective whiles the correlation between PM, O3 and CO2 is considered. A dielectric barrier discharge reactor has been designed with pulsed power technology to produce plasma inside the diesel exhaust. To characterise the system under varied conditions, a range of applied voltages from 11 kVPP to 21kVPP at repetition rates of 2.5, 5, 7.5 and 10 kHz, have been experimentally investigated. The results show that by increasing the applied voltage and repetition rate, higher discharge power and CO2 dissociation can be achieved. The PM removal efficiency of more than 50% has been achieved during the experiments and high concentrations of ozone on the order of a few hundreds of ppm have been observed at high discharge powers. Furthermore, O3, CO2 and PM concentrations at different plasma states have been analysed for time dependence. Based on this analysis, an inverse relationship between ozone concentration and PM removal has been found and the role of ozone in PM removal in plasma treatment of diesel exhaust has been highlighted.