首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9篇
  免费   0篇
能源动力   5篇
轻工业   1篇
一般工业技术   1篇
自动化技术   2篇
  2018年   1篇
  2016年   1篇
  2011年   1篇
  2008年   2篇
  2007年   1篇
  2006年   1篇
  2002年   1篇
  1989年   1篇
排序方式: 共有9条查询结果,搜索用时 62 毫秒
1
1.

The production of caricatures is a particularly interesting field of art, because it aims to highlight the very essence of a given face. Caricature generation systems traditionally rely on two approaches: they either follow extracted rules through learning algorithms, or follow rules that were directly programmed by experts. This paper attempts to reduce the reliance on heuristic methods, by proposing a novel method that provides a set of well-defined rules, which can be put to use for the purpose of caricature generation. The method is based on the notion of anti-face in conjunction with unbiased distortions. In addition, we indicate the usefulness of the anti-face as a means to perceive, for our own sake, the degree to which our face seems peculiar to others. Finally, we deploy a reverse variant of the method in order to attain beautification.

  相似文献   
2.
An enhanced beam element is proposed for the nonlinear dynamic analysis of skeletal structures. The formulation extends the displacement based elastic Timoshenko beam element. Shear-locking effects are eliminated using exact shape functions. A variant of the Bouc–Wen model is implemented to incorporate plasticity due to combined axial, shear and bending deformation components. Interaction is introduced through the implementation of yield functions, expressed in the stress resultant space. Three additional hysteretic degrees of freedom are introduced to account for the hysteretic part of the deformation components. Numerical results are presented that demonstrate the advantages of the proposed element in simulating cyclic phenomena, in which shear deformations are significant.  相似文献   
3.
In this paper we discuss the implementation of advanced variable connectivity Monte Carlo (MC) simulation methods for studying large (>105 atom) polymer systems at the atomic level. Such codes are intrinsically difficult to optimize since they involve a mixture of many different elementary MC steps, such as reptation, flip, end rotation, concerted rotation and volume fluctuation moves. In particular, connectivity altering MC moves, such as the recently developed directed end bridging (DEB) algorithm, are required in order to vigorously sample the configuration space. Techniques for effective vector implementation of such moves are described. We also show how a simple domain decomposition method can provide a general and efficient means of parallelizing these complex MC protocols. Benchmarks are reported for a 192,000 atom simulation of polydisperse linear polyethylene with an average chain length C6000, for simulations using 1 to 8 processors and a variety of MC protocols.  相似文献   
4.
Increased efficiency of energy demand is generally recognized as a very cost-effective strategy to reduce energy requirements and the related environmental impacts (e.g. the greenhouse effect). In order to improve energy efficiency the use of innovative market mechanisms, such as the White Certificates (WhC), has been proposed. The basic idea underlying this policy instrument is that specific energy saving targets are set for energy suppliers or energy distributors. These requirements must be fulfilled in a predefined time frame. The focus of this paper is on the effect on energy efficiency improvement, on the behavior of the end consumers and the market of energy efficiency measures. Furthermore, we study the possible effects of WhC in The Netherlands by means of a theoretical analysis and an empirical bottom-up model. We compare concrete energy efficient technologies in terms of cost-effectiveness and energy efficiency improvement. In combination with existing Dutch policies for energy efficiency improvement in the built environment, the contribution of this innovative scheme could enhance the accomplishment of energy efficiency targets. In this paper, two packages of energy saving measures of a WhC scheme are studied for Dutch households. The costs of these technologies are estimated through the use of different discount rates, which imply overcoming of the market barriers through the use of the WhC. A scheme that includes all available technologies as flexible options appears as a realistic solution and can generate cost effectively up to 180 PJ primary energy savings and 4550 M€ cumulative net savings in the year 2020, at a discount rate of 5%, under the precondition that the policy and administrative costs can be kept low.  相似文献   
5.
Hastening the energy saving rate in the built environment is a common goal of both the Dutch and the Greek government within the context of EU2020 strategy. In view of the recast Directive on the Energy Performance of Buildings (EPBD) (2010/31/EC), considered to be an important route towards exploiting the energy saving potential of the building stock, this paper conducted an ex-post assessment of the national Regulations on Energy Performance of Buildings (REPB) including energy performance certificates (EPCs), as transposed and implemented in Greece and the Netherlands. Results suggest that the implementation of the new EPBD requirements is still at an early stage for both countries. Similarities in the design of the two national schemes are demonstrated regarding quality assurance systems, while enforcement regimes show contrasting approaches with the Dutch EPCs operating at a voluntary basis. Both Dutch and the Greek scheme present a similar case regarding their low implementability, attributed though to dissimilar causes and external influences. Policy incoherence is another common characteristic traced between the two national yet different administration styles across governance levels, lacking of policy integration and coordination. The evaluation framework sheds some light on the understanding of the policy outcomes and design characteristics of the transposed REPB schemes in relation to the theory behind their implementation, while dealing with regulatory elements verified by observations and experiences, which need to be considered.  相似文献   
6.
The quantitative composition of the essential oils from two different Sideritis (Labiatae) species (S cladestina spp cyllenea and S sipylea) is reported. Over 80 components have been identified in each species by means of GC and GC? MS analysis, and a number of substances have been identified for the first time in these essential oils.  相似文献   
7.
In this paper, we analyze the experiences gained from tradable green certificate (TGC) schemes and extract some policy lessons that can lead to a successful design of a market-based approach for energy efficiency improvement, alias tradable white certificate schemes. We use tradable green certificate schemes existing in the Netherlands and Sweden as case studies. Departing from an assessment of both TGC schemes, we identify several institutional and market aspects that have affected their performance. We conduct the analysis by addressing key evaluation criteria (i.e., cost and energy effectiveness, administrative burden, technological innovation, political feasibility, and transaction costs). It is not our intention to demonstrate to the reader a normative aspect of designing tradable white certificate schemes. Rather, we identify some key policy lessons which can be summarized as: a binding long-term target must be clearly expressed in terms of policy time frame and certainty, a proper liquid market must be ensured for tradability of certificates, the scheme should be technology neutral, transaction costs should be kept low, and the energy efficiency target should not only address ‘low hanging fruits’ but also promote innovation.
Vlasis OikonomouEmail:
  相似文献   
8.
In this paper we analyze interactions of two energy policy instruments, namely a White Certificates (WhC) scheme as an innovative policy instrument for energy efficiency improvement and energy taxation. These policy instruments differ in terms of objectives and final impacts on the price of electricity. We examine the effect of these policy instruments in the electricity sector, focusing on electricity producers and suppliers in a competitive market. Using microeconomic theory, we identify synergies between market players and demonstrate the total effect on the electricity price when suppliers internalize the behaviour of producers in their decisions. This model refers to an ideal market situation of full liberalization. The cases we examine consist of electricity producers with and without a carbon tax, electricity suppliers with and without an electricity tax, and with WhC obligations. Furthermore, we present a parallel implementation of WhC for electricity suppliers with carbon tax on electricity producers and an electricity tax with WhC obligations to electricity suppliers. We demonstrate differences in optimization behaviour of producers and suppliers. Based on a couple of cases of WhC with carbon and electricity taxes, various positive and negative effects of both schemes in terms of target achievement and efficiency are present, which can lead to an added value of such schemes in the policy mix, although uncertainties of outcomes are quite high. A basic finding is that in a merit order several parameters can increase final electricity price after the implementation of different policies: demand for electricity and electricity supply cost at a large scale and then follow the level of level of obligation for energy saving, level of penalty, and price of WhC (representing the marginal costs of energy saving projects). The impact magnitude of parameters depends on the values chosen and on the initial position of suppliers (i.e. if their actual behaviour deviates from full compliance with targets).  相似文献   
9.
Worldwide, industry is responsible for about 40% of greenhouse gas (GHG) emissions, making it an important target for climate policy. Energy-intensive industries may be particularly vulnerable to higher energy costs caused by climate policy. If companies cannot offset rising energy costs and would face increased competition from countries without climate policy, they may decide to relocate their industrial production to the countries without climate policy. The resulting net effect of climate policy on GHG emissions in foreign countries is typically referred to as “carbon leakage”. Carbon leakage may lead to higher global GHG emissions due to the use of less advanced technology in less developed countries. Based on a literature review of climate policy, earlier environmental policy and analyses of historical trends, this paper assesses the carbon leakage effects of climate policy for energy-intensive industries. Reviews of past trends in production location of energy-intensive industries show an increased global production share of Non-Annex 1 countries. However, from empirical analyses we conclude that the trend is primarily driven by regional demand growth. In contrast, climate policy models show a strong carbon leakage. Even though future climate policy may have a more profound impact than environmental policies in the past, the modelling results are doubtful. Leakage generally seems to be overestimated in current models, especially as potential positive spillovers are often not included in the models. The ambiguity of the empirical analyses and the modelling results warrants further research in the importance of production factors for relocation.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号