791 resultados para cost-minimizing
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This study compares the procurement cost-minimizing and productive efficiency performance of the auction mechanism used by independent system operators (ISOs) in wholesale electricity auction markets in the U.S. with that of a proposed alternative. The current practice allocates energy contracts as if the auction featured a discriminatory final payment method when, in fact, the markets are uniform price auctions. The proposed alternative explicitly accounts for the market clearing price during the allocation phase. We find that the proposed alternative largely outperforms the current practice on the basis of procurement costs in the context of simple auction markets featuring both day-ahead and real-time auctions and that the procurement cost advantage of the alternative is complete when we simulate the effects of increased competition. We also find that a trade-off between the objectives of procurement cost minimization and productive efficiency emerges in our simple auction markets and persists in the face of increased competition.
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No âmbito da unidade curricular Dissertação/Projeto/Estágio do 2ºano do Mestrado em Engenharia mecânica – Ramo Gestão Industrial do Instituto Superior de Engenharia do Porto, o presente trabalho de dissertação foi enquadrado num projeto industrial de melhoria com Instituto Kaizen, empresa de consultoria operacional. O projeto foi desenvolvido numa empresa de produção de componentes em ferro nodular destinados à indústria automóvel do mercado europeu, a Sakthi Portugal,SA. A realização deste projeto teve como objetivo a implementação do sistema de planeamento em Pull (produção puxada) na logística interna da Sakthi Portugal,SA recorrendo à metodologia Kaizen. Esta metodologia consiste na aplicação de ferramentas de TFM - Total Flow Management, integradas no Kaizen Management System. Neste projeto recorreu-se especialmente a um dos pilares que o constituem, o pilar do “Fluxo da Logística Interna”. Neste pilar encontram-se as várias metodologias utilizadas na otimização do fluxo de material e informação na logística interna. Estas metodologias foram aplicadas, com o objetivo do sistema produtivo operar de acordo com a necessidade do cliente, obtendo deste modo a minimização dos custo e o aumento da produtividade e qualidade. Em resultado da aplicação da metodologia seguida, foi possível atingir-se os objetivos definidos inicialmente e em alguns casos foi possível superar esses objetivos. Em função da abordagem integrada que foi seguida, conseguiu-se uma diminuição do “lead time” do processo de fabrico, redução dos produtos em curso de fabrico, libertação de espaço e redução de inventários. Estas melhorias resultaram numa movimentação interna na fábrica mais facilitada e num aumento global da produtividade. Como consequência positiva dos efeitos deste trabalho, pode-se apontar o facto de que a Sakthi Portugal SA aumentou a sua competitividade por tornar-se numa empresa mais dinâmica, mais adaptada ao mercado e com níveis de satisfação do cliente muito superiores.
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Dissertação para obtenção do Grau de Doutor em Ambiente
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Tutkielmassa analysoidaan kunnan kassanhallinnan likvidimpien varojen prosessien toteuttamista, kun tavoitteena on kustannustehokkuuden parantaminen. Lisäksi selvitetään Etelä-Karjalan ydinkuntien eli Lappeenrannan, Imatran ja Joutsenon mahdollisuuksia tehostaa yhteistyötä taloushallinnon alueella. Työn teoriaosassa tarkastellaan kuntasektorin kassanhallintaa erityisesti myyntisaamisten ja ostovelkojen hallinnan osalta. Keskeistä on löytää prosesseista kustannuksia ja viivettä minimoivia menettelytapoja, joita olisi mahdollista hyödyntää kunnan kassanhallinnassa. Tehokkaassa kassanhallinnassa korostuu yhä enenevissä määrin informaatioteknologian rooli. Tästä johtuen tutkimuksessa kartoitetaan perinteisten menettelytapojen automatisoinnin mahdollisuuksia ja etuja. Empiirisessä osassa tarkastellaan kohdekuntien kassanhallinnan menettelytapoja sekä niiden yhtäläisyyksiä ja eroavuuksia. Lisäksi kartoitetaan yhteistyön lisäämisen mahdollisuuksia ja esteitä sekä määritetään käytetyn aineiston perusteella tehokkaan kassanhallinnan edellyttämät menettelytavat. Tutkimuksesta voidaan päätellä kuntien tavoittelevan joustavampia ja kustannuksia minivoivia kassanhallinnan menettelytapoja vaikka perinteisten menetelmien uudistaminen ei aina olekaan helppoa. Automatisointi ja prosessien virtaviivaistaminen on taloudellisen menestyksen ja kilpailussa mukana pysymisen edellytys. Tehokkuuden etsiminen tiiviimmän yhteistyön kautta olisi järkevää, mutta asenteet ja kontrollin menettämisen pelko estävät yhteistyöhön perustuvien suuruuden etujen saavuttamisen.
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Layout planning is a process of sizing and placing rooms (e.g. in a house) while a t t empt ing to optimize various criteria. Often the r e are conflicting c r i t e r i a such as construction cost, minimizing the distance between r e l a t ed activities, and meeting the area requirements for these activities. The process of layout planning ha s mostly been done by hand, wi th a handful of a t t empt s to automa t e the process. Thi s thesis explores some of these pa s t a t t empt s and describes several new techniques for automa t ing the layout planning process using evolutionary computation. These techniques a r e inspired by the existing methods, while adding some of the i r own innovations. Additional experimenLs are done to t e s t the possibility of allowing polygonal exteriors wi th rectilinear interior walls. Several multi-objective approaches are used to evaluate and compare fitness. The evolutionary r epr e s ent a t ion and requirements specification used provide great flexibility in problem scope and depth and is worthy of considering in future layout and design a t t empt s . The system outlined in thi s thesis is capable of evolving a variety of floor plans conforming to functional and geometric specifications. Many of the resulting plans look reasonable even when compared to a professional floor plan. Additionally polygonal and multi-floor buildings were also generated.
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Aus den im Rahmen dieser Forschungsarbeit empirisch gewonnenen Erkenntnissen werden Gestaltungsempfehlungen für das Public Debt Management abgeleitet. Diese zeigen, dass ein wirtschaftliches Public Debt Management nicht ein ausschließlich kostenminimierendes (sparsames), sondern ein kosten-risiko-optimales Public Debt Management mit effektiven internen und externen Überwachungsinstrumenten und wirksamer externer Finanzkontrolle sein muss.
Aversión al riesgo y eficiencia de escala en los bancos: Incluyendo variables de riesgo y regulación
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Este artículo aplica las teorías del enfoque moderno en la medición de la actividad bancaria. Con el fin de determinar la eficiencia de escala y el nivel de aversión al riesgo en los directivos de los bancos en Colombia, utiliza una función de costos translogarítmica multiproducto, que incorpora variables de riesgo y de regulación que caracterizaron y afectaron la actividad bancaria durante el período de crisis financiera. Encuentra que los directivos son adversos al riesgo y por lo tanto, la utilidad está en función de otras variables adicionales al beneficio. Demuestra que las medidas de regulación además de incrementar los costos generan un mayor nivel de aversión al riesgo de los directivos de los bancos, aumentando la demanda de capital financiero hasta niveles que no les permiten minimizar costos. Por último, encuentra que no existen economías de escala al incluir en su medición variables de riesgo y de regulación durante el período de desarrollo de la crisis financiera
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This thesis consists of a summary and five self-contained papers addressing dynamics of firms in the Swedish wholesale trade sector. Paper [1] focuses upon determinants of new firm formation in the Swedish wholesale trade sector, using two definitions of firms’ relevant markets, markets defined as administrative areas, and markets based on a cost minimizing behavior of retailers. The paper shows that new entering firms tend to avoid regions with already high concentration of other firms in the same branch of wholesaling, while right-of-the-center local government and quality of the infrastructure have positive impacts upon entry of new firms. The signs of the estimated coefficients remain the same regardless which definition of relevant market is used, while the size of the coefficients is generally higher once relevant markets delineated on the cost-minimizing assumption of retailers are used. Paper [2] analyses determinant of firm relocation, distinguishing between the role of the factors in in-migration municipalities and out-migration municipalities. The results of the analysis indicate that firm-specific factors, such as profits, age and size of the firm are negatively related to the firm’s decision to relocate. Furthermore, firms seems to be avoiding municipalities with already high concentration of firms operating in the same industrial branch of wholesaling and also to be more reluctant to leave municipalities governed by right-of-the- center parties. Lastly, firms seem to avoid moving to municipalities characterized with high population density. Paper [3] addresses determinants of firm growth, adopting OLS and a quantile regression technique. The results of this paper indicate that very little of the firm growth can be explained by the firm-, industry- and region-specific factors, controlled for in the estimated models. Instead, the firm growth seems to be driven by internal characteristics of firms, factors difficult to capture in conventional statistics. This result supports Penrose’s (1959) suggestion that internal resources such as firm culture, brand loyalty, entrepreneurial skills, and so on, are important determinants of firm growth rates. Paper [4] formulates a forecasting model for firm entry into local markets and tests this model using data from the Swedish wholesale industry. The empirical analysis is based on directly estimating the profit function of wholesale firms and identification of low- and high-return local markets. The results indicate that 19 of 30 estimated models have more net entry in high-return municipalities, but the estimated parameters is only statistically significant at conventional level in one of our estimated models, and then with unexpected negative sign. Paper [5] studies effects of firm relocation on firm profits of relocating firms, employing a difference-in-difference propensity score matching. Using propensity score matching, the pre-relocalization differences between relocating and non-relocating firms are balanced, while the difference-in-difference estimator controls for all time-invariant unobserved heterogeneity among firms. The results suggest that firms that relocate increase their profits significantly, in comparison to what the profits would be had the firms not relocated. This effect is estimated to vary between 3 to 11 percentage points, depending on the length of the analyzed period.
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The objective of this article is to study (understand and forecast) spot metal price levels and changes at monthly, quarterly, and annual horizons. The data to be used consists of metal-commodity prices in a monthly frequency from 1957 to 2012 from the International Financial Statistics of the IMF on individual metal series. We will also employ the (relatively large) list of co-variates used in Welch and Goyal (2008) and in Hong and Yogo (2009) , which are available for download. Regarding short- and long-run comovement, we will apply the techniques and the tests proposed in the common-feature literature to build parsimonious VARs, which possibly entail quasi-structural relationships between different commodity prices and/or between a given commodity price and its potential demand determinants. These parsimonious VARs will be later used as forecasting models to be combined to yield metal-commodity prices optimal forecasts. Regarding out-of-sample forecasts, we will use a variety of models (linear and non-linear, single equation and multivariate) and a variety of co-variates to forecast the returns and prices of metal commodities. With the forecasts of a large number of models (N large) and a large number of time periods (T large), we will apply the techniques put forth by the common-feature literature on forecast combinations. The main contribution of this paper is to understand the short-run dynamics of metal prices. We show theoretically that there must be a positive correlation between metal-price variation and industrial-production variation if metal supply is held fixed in the short run when demand is optimally chosen taking into account optimal production for the industrial sector. This is simply a consequence of the derived-demand model for cost-minimizing firms. Our empirical evidence fully supports this theoretical result, with overwhelming evidence that cycles in metal prices are synchronized with those in industrial production. This evidence is stronger regarding the global economy but holds as well for the U.S. economy to a lesser degree. Regarding forecasting, we show that models incorporating (short-run) commoncycle restrictions perform better than unrestricted models, with an important role for industrial production as a predictor for metal-price variation. Still, in most cases, forecast combination techniques outperform individual models.
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The objective of this article is to study (understand and forecast) spot metal price levels and changes at monthly, quarterly, and annual frequencies. Data consists of metal-commodity prices at a monthly and quarterly frequencies from 1957 to 2012, extracted from the IFS, and annual data, provided from 1900-2010 by the U.S. Geological Survey (USGS). We also employ the (relatively large) list of co-variates used in Welch and Goyal (2008) and in Hong and Yogo (2009). We investigate short- and long-run comovement by applying the techniques and the tests proposed in the common-feature literature. One of the main contributions of this paper is to understand the short-run dynamics of metal prices. We show theoretically that there must be a positive correlation between metal-price variation and industrial-production variation if metal supply is held fixed in the short run when demand is optimally chosen taking into account optimal production for the industrial sector. This is simply a consequence of the derived-demand model for cost-minimizing firms. Our empirical evidence fully supports this theoretical result, with overwhelming evidence that cycles in metal prices are synchronized with those in industrial production. This evidence is stronger regarding the global economy but holds as well for the U.S. economy to a lesser degree. Regarding out-of-sample forecasts, our main contribution is to show the benefits of forecast-combination techniques, which outperform individual-model forecasts - including the random-walk model. We use a variety of models (linear and non-linear, single equation and multivariate) and a variety of co-variates and functional forms to forecast the returns and prices of metal commodities. Using a large number of models (N large) and a large number of time periods (T large), we apply the techniques put forth by the common-feature literature on forecast combinations. Empirically, we show that models incorporating (short-run) common-cycle restrictions perform better than unrestricted models, with an important role for industrial production as a predictor for metal-price variation.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Economic models have demonstrated the efficiency of curbside collection taxes. This paper demonstrates that such efficiencies disappear in economies with centralized recycling options - where recyclable materials can be removed from the waste stream either by households or at a centralized recycling facility. In such economies a curbside garbage tax not only fails to encourage the centralized recycler to internalize the external costs of waste disposal, but introduces inefficiencies to the cost-minimizing mix of household and centralized recycling efforts. The optimal waste policy is a tax assessed further downstream at the landfill rather than at the curb.
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This paper estimates the average social cost of municipal waste management as a function of the recycling rate. Social costs include all municipal costs and revenues, costs to recycling households to prepare materials estimated with an original method, external disposal costs, and external recycling benefits. Results suggest average social costs are minimized with recycling rates well below observed and mandated levels in Japan. Cost-minimizing municipalities are estimated to recycle less than the optimal rate. These results are robust to changes in the components of social costs, indicating that Japan and perhaps other developed countries may be setting inefficiently high recycling goals. (C) 2014 Elsevier Inc. All rights reserved.
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In this paper we develop a simple economic model to analyze the use of a policy that combines a voluntary approach to controlling nonpoint-source pollution with a background threat of an ambient tax if the voluntary approach is unsuccessful in meeting a pre-specified environmental goal. We first consider the case where the policy is applied to a single farmer, and then extend the analysis to the case where the policy is applied to a group of farmers. We show that in either case such a policy can induce cost-minimizing abatement without the need for farm-specific information. In this sense, the combined policy approach is not only more effective in protecting environmental quality than a pure voluntary approach (which does not ensure that water quality goals are met) but also less costly than a pure ambient tax approach (since it entails lower information costs). However, when the policy is applied to a group of farmers, we show that there is a potential tradeoff in the design of the policy. In this context, lowering the cutoff level of pollution used for determining total tax payments increases the likely effectiveness of the combined approach but also increases the potential for free riding. By setting the cutoff level equal to the target level of pollution, the regulator can eliminate free riding and ensure that cost-minimizing abatement is the unique Nash equilibrium under which the target is met voluntarily. However, this cutoff level also ensures that zero voluntary abatement is a Nash equilibrium. In addition, with this cutoff level the equilibrium under which the target is met voluntarily will not strictly dominate the equilibrium under which it is not. We show that all results still hold if the background threat instead takes the form of reducing government subsidies if a pre-specified environmental goal is not met.
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This study of the wholesale electricity market compares the cost-minimizing performance of the auction mechanism currently in place in U.S. markets with the performance of a proposed replacement. The current mechanism chooses an allocation of contracts that minimizes a fictional cost calculated using pay-as-offer pricing. Then suppliers are paid the market clearing price. The proposed mechanism uses the market clearing price in the allocation phase as well as in the payment phase. In concentrated markets, the proposed mechanism outperforms the current mechanism even when strategic behavior by suppliers is taken into account. The advantage of the proposed mechanism increases with increased price competition.