845 resultados para efficiency wage


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This study aimed to evaluate the effect of Moringa oleifera Lam extract on the removal of total solids (TS), total suspended solids (TSS) and chemical oxygen demand (COD), in different filter media for treating wastewater of dairy cattle breeding (DCW). The moringa seed extract was obtained by grinding 50 g of seeds in one liter of distilled water and, after passing the solution through a quantitative paper filter of 25 microns, 60 mL of the extract were added to wastewater from cattle breeding before the filtration process in organic filters made of thin coal, bamboo leaves, eucalyptus leaves, gliricidia branches and sawdust. This was followed by the completely randomized experimental design, adopting a factorial of 5 x 2. Aliquots of filtered effluent were collected and the total solids (TS) concentrations, total suspended solids (TSS) and chemical oxygen demand (COD) were determined. It was found that the increase in the efficiency of removal of COD and total solids can be attributed to the coagulating power of the moringa seed extract, wherein the filter medium with bamboo leaves presented the best performance, showing potential for use as alternative filter material in the primary treatment of DCW.

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Citrus orchards are very important in Brazil, especially in São Paulo State, where occupy an area of 600,000 ha approximately. To identify sustainability degree of citrus production system, an energy analysis allows evaluating efficiency of direct and indirect applied inputs. Thus, this study aimed to evaluate citrus production system under energetic point of view, in which invested energy is paid back with citrus production; being compared within three scenarios for operational field efficiency. As result, by sensitivity analysis was determined that fuel was the main energy demander, followed by pesticides and fertilizers. In operational work capacity analysis, all combinations between efficiency (minimum, typical and maximum) and yield levels became positive in the seventh year, except for the combination minimum efficiency and 10 % less yield, positive in the eighth year. The best combination (maximum efficiency and 10 % more yield) has promoted investment payoff around the sixth and seventh year. By this study, it is possible to determine the total energy demand to produce citrus and indentify the applied inputs that need more attention by the decision-makers. Labor and seedlings can be ommited for further studies with citrus, since they were irrelevant. Management of agricultural machinery may pose an important role on decreasing environmental impact of citrus production.

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ABSTRACT The objective of this research was to evaluate the thermal efficiency of roofs used on individual shelters during milk-feeding stage of Girolando calves. The research was conducted at a farm located in a dry region of Pernambuco state, Brazil. The experimental design was completely randomized, with 27 Holstein × Gir dairy crossbred calves housed in shelters with three roofing materials (fibre cement tile, recycled tile, and thatched roofs). The recycled tiles and thatched roofs provided reductions of 18.7 and 14.6% in radiant thermal load, respectively. Regardless the roofing material, all animals increased their respiratory rate to maintain thermal equilibrium.

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The purpose of this master’s thesis was to study ways to increase the operating cost-efficiency of the hydrogen production process by optimizing the process parameters while, at the same time, maintaining plant reliability and safety. The literature part reviewed other hydrogen production and purification processes as well as raw material alternatives for hydrogen production. The experimental part of the master’s thesis was conducted at Solvay Chemicals Finland Oy’s hydrogen plant in spring 2012. It was performed by changing the process parameters, first, one by one, aiming for a more efficient process with clean product gas and lower natural gas consumption. The values of the process parameters were tested based on the information from the literature, process simulation and experiences of previous similar processes. The studied parameters were reformer outlet temperature, shift converter inlet temperature and steam/carbon ratio. The results show that the optimal process conditions are a lower steam/carbon ratio and reformer outlet temperature than the current values of 3.0 and 798 °C. An increase/decrease in the shift conversion inlet temperature does not affect natural gas consumption, but it has an effect on minimizing the process steam overload.

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This study investigates futures market efficiency and optimal hedge ratio estimation. First, cointegration between spot and futures prices is studied using Johansen method, with two different model specifications. If prices are found cointegrated, restrictions on cointegrating vector and adjustment coefficients are imposed, to account for unbiasedness, weak exogeneity and prediction hypothesis. Second, optimal hedge ratios are estimated using static OLS, and time-varying DVEC and CCC models. In-sample and out-of-sample results for one, two and five period ahead are reported. The futures used in thesis are RTS index, EUR/RUB exchange rate and Brent oil, traded in Futures and options on RTS.(FORTS) For in-sample period, data points were acquired from start of trading of each futures contract, RTS index from August 2005, EUR/RUB exchange rate March 2009 and Brent oil October 2008, lasting till end of May 2011. Out-of-sample period covers start of June 2011, till end of December 2011. Our results indicate that all three asset pairs, spot and futures, are cointegrated. We found RTS index futures to be unbiased predictor of spot price, mixed evidence for exchange rate, and for Brent oil futures unbiasedness was not supported. Weak exogeneity results for all pairs indicated spot price to lead in price discovery process. Prediction hypothesis, unbiasedness and weak exogeneity of futures, was rejected for all asset pairs. Variance reduction results varied between assets, in-sample in range of 40-85 percent and out-of sample in range of 40-96 percent. Differences between models were found small, except for Brent oil in which OLS clearly dominated. Out-of-sample results indicated exceptionally high variance reduction for RTS index, approximately 95 percent.

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Transportation and warehousing are large and growing sectors in the society, and their efficiency is of high importance. Transportation also has a large share of global carbondioxide emissions, which are one the leading causes of anthropogenic climate warming. Various countries have agreed to decrease their carbon emissions according to the Kyoto protocol. Transportation is the only sector where emissions have steadily increased since the 1990s, which highlights the importance of transportation efficiency. The efficiency of transportation and warehousing can be improved with the help of simulations, but models alone are not sufficient. This research concentrates on the use of simulations in decision support systems. Three main simulation approaches are used in logistics: discrete-event simulation, systems dynamics, and agent-based modeling. However, individual simulation approaches have weaknesses of their own. Hybridization (combining two or more approaches) can improve the quality of the models, as it allows using a different method to overcome the weakness of one method. It is important to choose the correct approach (or a combination of approaches) when modeling transportation and warehousing issues. If an inappropriate method is chosen (this can occur if the modeler is proficient in only one approach or the model specification is not conducted thoroughly), the simulation model will have an inaccurate structure, which in turn will lead to misleading results. This issue can further escalate, as the decision-maker may assume that the presented simulation model gives the most useful results available, even though the whole model can be based on a poorly chosen structure. In this research it is argued that simulation- based decision support systems need to take various issues into account to make a functioning decision support system. The actual simulation model can be constructed using any (or multiple) approach, it can be combined with different optimization modules, and there needs to be a proper interface between the model and the user. These issues are presented in a framework, which simulation modelers can use when creating decision support systems. In order for decision-makers to fully benefit from the simulations, the user interface needs to clearly separate the model and the user, but at the same time, the user needs to be able to run the appropriate runs in order to analyze the problems correctly. This study recommends that simulation modelers should start to transfer their tacit knowledge to explicit knowledge. This would greatly benefit the whole simulation community and improve the quality of simulation-based decision support systems as well. More studies should also be conducted by using hybrid models and integrating simulations with Graphical Information Systems.

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This thesis consists of four articles and an introductory section. The main research questions in all the articles refer to the changes in the representativeness of the Finnish Paper Workers' Union. Representativeness stands for the entire entity of external, internal, legal and reputational factors that enable the labor union to represent its members and achieve its goals. This concept is based on an extensive reading of quantitative and qualitative industrial relations literature, which includes works based on Marxist labor-capital relations (such as Hyman's industrial relations studies), and more recent union density studies as well as gender- and ethnic diversity-based 'union revitalization' studies. Müller-Jentsch's German studies of industrial relations have been of particular importance as well as Streeck's industrial unionism and technology studies. The concept of representativeness is an attempt to combine the insights of these diverse strands of literature and bring the scientific discussion of labor unions back to the core of a union's function: representing its members. As such, it can be seen as a theoretical innovation. The concept helps to acknowledge both the heterogeneity of the membership and the totality of a labor union organization. The concept of representativeness aims to move beyond notions of 'power'. External representativeness can be expressed through the position of the labor union in the industrial relations system and the economy. Internal representativeness focuses on the aspects of labor unions that relate to the function of the union as an association with members, such as internal democracy. Legal representativeness lies in the formal legal position of the union – its rights and instruments. This includes collective bargaining legislation, co-decision rules and industrial conflict legislation. Reputational representativeness is related to how the union is seen by other actors and the general public, and can be approximated using data on strike activity. All these aspects of representativeness are path-dependent, and show the results of previous struggles over issues. The concept of representativeness goes beyond notions of labor union power and symbolizes an attempt to bring back the focus of industrial relations studies to the union's basic function of representing its members. The first article shows in detail the industrial conflict of the Finnish paper industry in 2005. The intended focus was the issue of gender in the negotiations over a new collective agreement, but the focal point of the industrial conflict was the issue of outsourcing and how this should be organized. Also, the issue of continuous shifts as an issue of working time was very important. The drawn-out conflict can be seen as a struggle over principles, and under pressure the labor union had to concede ground on the aforementioned issues. The article concludes that in this specific conflict, the union represented its' female members to a lesser extent, because the other issues took such priority. Furthermore, because of the substantive concessions. the union lost some of its internal representativeness, and the stubbornness of the union may have even harmed the reputation of the union. This article also includes an early version of the representativeness framework, through which this conflict is analyzed. The second article discusses wage developments, union density and collective bargaining within the context of representativeness. It is shown that the union has been able to secure substantial benefits for its members, regardless of declining employment. Collective agreements have often been based on centralized incomes policies, but the paper sector has not always joined these. Attention is furthermore paid to the changing competition of the General Assembly, with a surprisingly strong position of the Left Alliance still. In an attempt to replicate analysis of union density measures, an analysis of sectoral union density shows that similar factors as in aggregate data influence this measure, though – due to methodological issues – the results may not be robust. On this issue, it can be said that the method of analysis for aggregate union density is not suitable for sectoral union density analysis. The increasingly conflict-ridden industrial relations predicted have not actually materialized. The article concludes by asking whether the aim of ever-increasing wages is a sustainable one in the light of the pressures of globalization, though wage costs are a relatively small part of total costs. The third article discusses the history and use of outsourcing in the Finnish paper industry. It is shown using Hyman's framework of constituencies that over time, the perspective of the union changed from 'members of the Paper Workers' Union' to a more specific view of who is a core member of the union. Within the context of the industrial unionism that the union claims to practice, this is an important change. The article shows that the union more and more caters for a core group, while auxiliary personnel is less important to the union's identity and constituencies, which means that the union's internal representativeness has decreased. Maintenance workers are an exception; the union and employers have developed a rotating system that increases the efficient allocation of these employees. The core reason of the exceptional status of maintenance personnel is their high level of non-transferable skills. In the end it is debatable whether the compromise on outsourcing solves the challenges facing the industry. The fourth article shows diverging discourses within the union with regard to union-employer partnership for competitiveness improvements and instruments of local union representatives. In the collective agreement of 2008, the provision regulating wage effects of significant changes in the organization or content of work was thoroughly changed, though this mainly reflected decisions by the Labor Court on the pre-2008 version of the provision. This change laid bare the deep rift between the Social Democratic and Left Alliance (ex-Communist) factions of the union. The article argues that through the changed legal meaning of the provision, the union was able to transform concession bargaining into a basis for partnership. The internal discontent about this issue is nonetheless substantial and a threat to the unity of the union, both locally and at the union level. On the basis of the results of the articles, other factors influencing representativeness, such as technology and EU law and an overview of the main changes in the Finnish paper industry, it is concluded that, especially in recent years, the Finnish Paper Workers' Union has lost some of its representativeness. In particular, the loss of the efficiency of strikes is noted, the compromise on outsourcing which may have alienated a substantial part of the union's membership, and the change in the collective agreement of 2008 have caused this decline. In the latter case, the internal disunion on that issue shows the constraints of the union's internal democracy. Furthermore, the failure of the union to join the TEAM industrial union (by democratic means), the internal conflicts and a narrow focus on its own sector may also hurt the union in the future, as the paper industry in Finland is going through a structural change. None of these changes in representativeness would have been so drastic without the considerable pressure of globalization - in particular changing markets, changing technology and a loss of domestic investments to foreign investments, which in the end have benefited the corporations more than the Finnish employees of these corporations. Taken together, the union risks becoming socially irrelevant in time, though it will remain formally very strong on the basis of its institutional setting and financial situation.

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The management of port-related supply chains is challenging due to the complex and heterogeneous operations of the ports with several actors and processes. That is why the importance of information sharing is emphasised in the ports. However, the information exchange between different port-related actors is often cumbersome and it still involves a lot of manual work and paper. Major ports and port-related actors usually have advanced information systems in daily use but these systems are seldom interoperable with each other, which prevents economies of scale to be reached. Smaller ports and companies might not be equipped with electronic data transmission at all. This is the final report of the Mobile port (MOPO) project, which has sought ways to improve the management and control of port-related sea and inland traffic with the aid of ICT technologies. The project has studied port community systems (PCS) used worldwide, evaluated the suitability of a PCS for the Finnish port operating environment and created a pilot solution of a Finnish PCS in the port of HaminaKotka. Further, the dry port concept and its influences on the transportation system have been explored. The Mobile Port project comprised of several literature reviews, interviews of over 50 port-related logistics and/or ICT professionals, two different kinds of simulation models as well as designing and implementing of the pilot solution of the Finnish PCS. The results of these multiple studies are summarised in this report. Furthermore, recommendations for future actions and the topics for further studies are addressed in the report. The study revealed that the information sharing in a typical Finnish port-related supply chain contains several bottlenecks that cause delays in shipments and waste resources. The study showed that many of these bottlenecks could be solved by building a port community system for the Finnish port community. Almost 30 different kinds of potential services or service entities of a Finnish PCS were found out during the study. The basic requirements, structure, interfaces and operation model of the Finnish PCS were also defined in the study. On the basis of the results of the study, a pilot solution of the Finnish PCS was implemented in the port of HaminaKotka. The pilot solution includes a Portconnect portal for the Finnish port community system (available at https://www.portconnect.fi) and two pilot applications, which are a service for handling the information flows concerning the movements of railway wagons and a service for handling the information flows between Finnish ports and Finland-Russian border. The study also showed that port community systems can be used to improve the environmental aspects of logistics in two different ways: 1) PCSs can bring direct environmental benefits and 2) PCSs can be used as an environmental tool in a port community. On the basis of the study, the development of the Finnish port community system should be continued by surveying other potential applications for the Finnish PCS. It is also important to study if there is need and resources to extend the Finnish PCS to operate in several ports or even on a national level. In the long run, it could be reasonable to clarify whether there would be possibilities to connect the Finnish PCS as a part of Baltic Sea wide, European-wide or even worldwide maritime and port-related network in order to get the best benefit from the system

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Besides the sustaining of healthy and comfortable indoor climate, the air conditioning system should also achieve for energy efficiency. The target indoor climate can be ob-tained with different systems; this study focuses on comparing the energy efficiency of different air conditioning room unit systems in different climates. The calculations are made with dynamic energy simulation software IDA ICE by comparing the indoor cli-mate and energy consumption of an office building with different systems in different climates. The aim of the study is to compare the energy efficiency of chilled beam systems to other common systems: variable air volume, fan coil and radiant ceiling systems. Besides the annual energy consumption also the sustainability of target indoor climate is compared between the simulations. Another aim is to provide conclusions to be used in the product development of the chilled beam systems’ energy efficiency. The adaptable chilled beam system and the radiant ceiling system prove to be energy efficient independent of the climate. The challenge of reliable comparison is that other systems are not able to reach the target indoor climate as well as the others. The complex calculation environment of the simulation software, made assumptions and excluding of the financial aspects complicate comparing the big picture. The results show that the development of the chilled beam systems should concentrate on energy efficient night heating, flexible demand based ventilation and capacity control and possibilities on integrating the best practices with other systems. 

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The power demand of many mobile working machines such as mine loaders, straddle carriers and harvesters varies significantly during operation, and typically, the average power demand of a working machine is considerably lower than the demand for maximum power. Consequently, for most of the time, the diesel engine of a working machine operates at a poor efficiency far from its optimum efficiency range. However, the energy efficiency of dieseldriven working machines can be improved by electric hybridization. This way, the diesel engine can be dimensioned to operate within its optimum efficiency range, and the electric drive with its energy storages responds to changes in machine loading. A hybrid working machine can be implemented in many ways either as a parallel hybrid, a series hybrid or a combination of these two. The energy efficiency of hybrid working machines can be further enhanced by energy recovery and reuse. This doctoral thesis introduces the component models required in the simulation model of a working machine. Component efficiency maps are applied to the modelling; the efficiency maps for electrical machines are determined analytically in the whole torque–rotational speed plane based on the electricalmachine parameters. Furthermore, the thesis provides simulation models for parallel, series and parallel-series hybrid working machines. With these simulation models, the energy consumption of the working machine can be analysed. In addition, the hybridization process is introduced and described. The thesis provides a case example of the hybridization and dimensioning process of a working machine, starting from the work cycle of the machine. The selection and dimensioning of the hybrid system have a significant impact on the energy consumption of a hybrid working machine. The thesis compares the energy consumption of a working machine implemented by three different hybrid systems (parallel, series and parallel-series) and with different component dimensions. The payback time of a hybrid working machine and the energy storage lifetime are also estimated in the study.

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This study is a survey of benefits and drawbacks of embedding a variable gearbox instead of a single reduction gear in electric vehicle powertrain from efficiency point of view. Losses due to a pair of spur gears meshing with involute teeth are modeled on the base of Coulomb’s law and fluid mechanics. The model for a variable gearbox is fulfilled and further employed in a complete vehicle simulation. Simulation model run for a single reduction gear then the results are taken as benchmark for other types of commonly used transmissions. Comparing power consumption, which is obtained from simulation model, shows that the extra load imposed by variable transmission components will shade the benefits of efficient operation of electric motor. The other accomplishment of this study is a combination of modified formulas that led to a new methodology for power loss prediction in gear meshing which is compatible with modern design and manufacturing technology.

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The behavioural finance literature expects systematic and significant deviations from efficiency to persist in securities markets due to behavioural and cognitive biases of investors. These behavioural models attempt to explain the coexistence of intermediate-term momentum and long-term reversals in stock returns based on the systematic violations of rational behaviour of investors. The study investigates the anchoring bias of investors and the profitability of the 52-week momentum strategy (GH henceforward). The relatively highly volatile OMX Helsinki stock exchange is a suitable market for examining the momentum effect, since international investors tend to realise their positions first from the furthest security markets by the time of market turbulence. Empirical data is collected from Thomson Reuters Datastream and the OMX Nordic website. The objective of the study is to provide a throughout research by formulating a self-financing GH momentum portfolio. First, the seasonality of the strategy is examined by taking the January effect into account and researching abnormal returns in long-term. The results indicate that the GH strategy is subject to significantly negative revenues in January, but the strategy is not prone to reversals in long-term. Then the predictive proxies of momentum returns are investigated in terms of acquisition prices and 52-week high statistics as anchors. The results show that the acquisition prices do not have explanatory power over the GH strategy’s abnormal returns. Finally, the efficacy of the GH strategy is examined after taking transaction costs into account, finding that the robust abnormal returns remain statistically significant despite the transaction costs. As a conclusion, the relative distance between a stock’s current price and its 52-week high statistic explains the profits of momentum investing to a high degree. The results indicate that intermediateterm momentum and long-term reversals are separate phenomena. This presents a challenge to current behavioural theories, which model these aspects of stock returns as subsequent components of how securities markets respond to relevant information.

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This study aimed to assess and evaluate the effects of Theileria equi infection on embryonic recovery, gestation and early embryonic loss. Thirteen Mangalarga Marchador Theileria equi positive donors (diagnosed through nested-PCR) and 40 embryos receptors were used. Donors were submitted to two embryo collections in two consecutive estrous cycles (GId); after, the same mares were treated with imidocarb dipropionate (1.2mg/kg IM.) in order to collect more embryos in two more estrous cycles (GIId). Receptors were divided into two groups (control and with treated) with 20 animals each, where one group was the control (GIr) and the other one (GIIr) treated with 1.2mg/kg IM of imidocarb dipropionate assessing the gestation rate at 15, 30, 45 and 60 days. After 52 embryo collections, the embryonic recovery rates were 53.84% (14/26) and 65.38% (17/26) (p> 0.05) for GId and GIId, respectively. The gestation rate was 70% (14/20) (p>0.05) at 15, 30, 45 and 60 days in group GIr and for GIIr was 85% (17/20) (p>0.05) at 15 days, 80% (16/20) (p>0.05) at 30, 45 and 60 days. The treatment with imidocarb dipropionate did not cause significant improvement in the reproductive efficiency at an ET program.

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Process planning is a very important industrial activity, since it determines how a part or a product is manufactured. Process planning decisions include machine selection, tool selection, and cutting conditions determination, and thus it is a complex activity. In the presence of unstable demand, flexibility has become a very important characteristic of today's successful industries, for which Flexible Manufacturing Systems (FMSs) have been proposed as a solution. However, we believe that FMS control software is not flexible enough to adapt to different manufacturing system conditions aiming at increasing the system's efficiency. One means to overcome this limitation is to include pre-planned alternatives in the process plan; then planning decisions are made by the control system in real time to select the most appropriate alternative according to the conditions of the shop floor. Some of the advantages of this approach reported in the literature are the reduction of the number of tool setups, and the selection of a replacement machine for executing an operation. To verify whether the presence of alternatives in process plans actually increases the efficiency of the manufacturing system, an investigation was carried out using simulation and design of experiments techniques for alternative plans on a single machine. The proposed methodology and the results are discussed within this paper.