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991.
992.
The ease with which 3D CAD models may be modified and reused are two key aspects that improve the design-intent variable and that can significantly shorten the development timelines of a product. A set of rules are gathered from various authors that take different 3D modelling strategies into account. These rules are then applied to CAD strategic-knowledge learning methodology and included in 3D CAD modelling exercises for students following the degree in mechanical engineering at the University of Burgos (Spain). The experiment was conducted in two groups with a total of 75 students. The design-intent rules were introduced in the different exercises that the teacher explained in both the theoretical and the practical classes. In addition, a summary of the different design rules in each of the practical exercises was explained in the practical classes in only one of the groups. The experimental results, reported in this paper, tested the influence of these summaries on overall improvements in 3D modelling and on the design-intent variable, which is subdivided into four sections: skeleton, structures, alterations and constraints. The use of the summaries of the design intent rules led to statistically significant improvements in 3D modelling in the experimental group, in comparison with the group of students to whom those summaries were not explained.  相似文献   
993.
More than a year after a court invalidated its “net neutrality” rules on broadband Internet service providers (ISPs), the Federal Communications Commission (FCC) decided to extend public-utility (Title II) regulation on broadband services. This paper uses traditional event analysis of the movements in the values of major communications and media companies’ equities at key moments in the FCC’s path to this decision to estimate the financial market’s assessment of the likely effects of regulation on ISPs, traditional media companies, and new digital media companies. The results are surprising: the markets penalized only three large cable companies to any extent, and even these effects appear to have been short-lived. The media companies, arguably the intended beneficiaries of the regulations, were unaffected.  相似文献   
994.
The legal framing of a firm’s pricing strategy can determine whether it constitutes online resale price maintenance (RPM) or online most favored nation (MFN). Together, cases that involve online RPM and MFN can be viewed as a natural experiment of how antitrust economics and law may adapt to an online world. Thus far, legal theories that have been inconsistent with economic theories have dictated enforcement across jurisdictions, which has led to confusion that thwarts potentially efficient business practices. This paper distinguishes issues of online RPM from traditional RPM and online RPM from online MFN. We apply the economics learning to RPM and analyze the antitrust cases of online RPM and MFN to date in the United States, Europe, and Australia. Finally, we offer policy recommendations that reduce the confusion in current legal doctrine.  相似文献   
995.
The reorientations of energy policy, and in particular the promotion of renewables, have changed the market conditions for energy companies significantly. Over recent years, the resulting challenges put the energy companies’ financial ratios under severe stress. As the need to invest remains urgent, energy firms seek to broaden and diversify their sources of funding. Against this backdrop, the article addresses an innovative form of securities-based debt financing for energy companies, which explicitly links the financing transaction to the investing of funds in renewable energy projects. Due to the early stage of development of so called green (project) bonds, an initial disambiguation is essential. Thereafter, current market processes, structures and rules are considered. Based hereupon, it is possible to discuss the new opportunities that green project bonds afford energy companies.  相似文献   
996.
Germany has only very limited domestic energy resources. Seventy percent of primary energy needs must be covered by imports. The markets for energy are marked by a wide diversity and a large number of providers. The oil market has been intensely competitive for decades now. Lignite and hard coal are subjected to fierce substitution competition, especially with natural gas. The natural gas and electricity markets were fully liberalized in 1998. Consumers can freely choose from a vast number of suppliers. Since the beginning of this century, however, state interference particularly in the electricity market has increased. The expansion of renewables has been promoted since the year 2000 by feed-in priority and feed-in remunerations regulated by the state. The energy transition initiated in 2011 is characterized by ambitious energy and climate policy targets. Key pillars include the conversion of electricity generation from production on the basis of conventional energy sources to a system based mainly on renewable energies combined with stringent requirements designed to enhance energy efficiency and what are probably the most ambitious climate protection targets worldwide. As regards the expansion of renewables and the phase-out of nuclear energy, Germany is keeping to its target path. By contrast, there are no signs yet that the objectives formulated in terms of the lowering of primary energy consumption and the reduction in greenhouse gas emissions will be achieved.  相似文献   
997.
998.
We propose a valuation method for financial assets subject to default risk, where investors cannot observe the state variable triggering the default but observe a correlated price process. The model is sufficiently general to encompass a large class of structural models and can be seen as a generalization of the model of Duffie and Lando (Econometrica 69:633–664, [2001]). In this setting we prove that the default time is totally inaccessible in the market’s filtration and derive the conditional default probabilities and the intensity process. Finally, we provide pricing formulas for default-sensitive claims and illustrate in particular examples the shapes of the credit spreads.   相似文献   
999.
The purpose of this paper is to describe the appropriate mathematical framework for the study of the duality principle in option pricing. We consider models where prices evolve as general exponential semimartingales and provide a complete characterization of the dual process under the dual measure. Particular cases of these models are the ones driven by Brownian motions and by Lévy processes, which have been considered in several papers. Generally speaking, the duality principle states that the calculation of the price of a call option for a model with price process S=e H (with respect to the measure P) is equivalent to the calculation of the price of a put option for a suitable dual model S′=e H (with respect to the dual measure P′). More sophisticated duality results are derived for a broad spectrum of exotic options. The second named author acknowledges the financial support from the Deutsche Forschungsgemeinschaft (DFG, Eb 66/9-2). This research was carried out while the third named author was supported by the Alexander von Humboldt foundation.  相似文献   
1000.
International travellers are frequently offered the opportunity to purchase a certain quantity of goods duty-free. Individuals differ in their opportunities to benefit from duty-free shopping, and we focus on the implications of these differences for optimal commodity taxation within a version of the optimal tax model of Mirrlees (Review of Economic Studies, 38, 175–208, 1971). We show how duty-free alters the constraints on the use of commodity taxes to reduce the distortionary costs of income taxation or to reflect externalities. Beyond characterising optimal taxes in the duty-free regime, we discuss conditions under which allowing duty-free would increase or reduce social welfare.   相似文献   
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