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Greenhouse Gas Reduction Pathways: In the UNFCCC Process up to 2025
Meeting the EU objective of limiting global average temperature increase to 2 degrees Celsius above pre-industrial levels requires a peak in global greenhouse gas emissions within the next two decades. This means that early participation of developing countries in global emission control is needed, even under a significant strengthening of the commitments of Annex I countries under the Kyoto Protocol. The study has shown that it is possible to design a set of consistent rules for the attribution of the long-term emission endowments of the different world regions. The gains from participating in global emission trading and from reduced air pollution damage and/or abatement costs does substantially enhance, from a developing country perspective, the attractiveness of an early participation in a regime based on greenhouse gas reduction pathways, provided that the level and the form of their commitment is well designed so as to minimise economic risks
Technological Change in Economic Models of Environmental Policy: A Survey
This paper provides an overview of the treatment of technological change in economic models of environmental policy. Numerous economic modeling studies have confirmed the sensitivity of mid- and long-run climate change mitigation cost and benefit projections to assumptions about technology costs. In general, technical progress is considered to be a noneconomic, exogenous variable in global climate change modeling. However, there is overwhelming evidence that technological change is not an exogenous variable but to an important degree endogenous, induced by needs and pressures. Hence, some environmenteconomy models treat technological change as endogenous, responding to socio-economic variables. Three main elements in models of technological innovation are: (i) corporate investment in research and development, (ii) spillovers from R&D, and (iii) technology learning, especially learning-by-doing. The incorporation of induced technological change in different types of environmental-economic models tends to reduce the costs of environmental policy, accelerates abatement and may lead to positive spillover and negative leakage
GAIN MARGINS AND ROOT LOCUS ASYMPTOTIC-BEHAVIOR IN MULTIVARIABLE DESIGN .1. PROPERTIES OF MARKOV PARAMETERS AND USE OF HIGH FEEDBACK GAIN
From a root locus point of view the ability of a feedback system to tolerate high gains depends on the distribution of the finite zeros (FZ) and the infinite zeros (IZ). The asymptotic directions of the closed loop poles that tend to the IZ with increasing scalar gain are determined by the eigfenproperties of a set of parameters called the projected Markov parameters (PMP). Furthermore the points of radiation of the asymptotes called the pivots may also be computed in terms of the elementary state space matrices. The dependence of the order of the IZ and therefore the distribution of the asymptotes on the null structure of the PMP is discussed first and subsequently a design technique which aims at the reduction of the order of the IZ as well as the placement of the corresponding pivots is proposed. The effectiveness of such a desigfn technique in improving the gain margins of feedback systems is illustrated by means of a numerical example
GEOMETRIC APPROACH TO INVERSION OF MULTIVARIABLE SYSTEMS
The input and output matrix maps B and C of a linear multivariable system S(A,B,C) play an important role in determining the behaviour of the system. Square systems with the produce CB full rank possess a simple state-space geometry which is deployed in the present paper for the derivation of an explicit state-space characterization of the inverse system. An efficient algorithm for the inversion of a system is then obtained. The elegance of the results discussed enables the examination of the duality between poles/modes and zeros/zero-directions. Finally, an extension of the above to systems with CB rank-deficient is undertaken
COMPLEX ALIGN - A TECHNIQUE FOR THE CHARACTERISTIC LOCUS METHOD OF DESIGN
Eigenvector alignment techniques play an important role in the characteristic locus design of commutative controllers for multivariable systems. Previous work restricted attention to the approximation of eigenvectors by real constant vectors. The paper extends the flexibility and effectiveness of the design by considering the approximation of eigenvector pairs by constant complex-conjugate vectors
GAIN MARGINS AND ROOT LOCUS ASYMPTOTIC-BEHAVIOR IN MULTIVARIABLE DESIGN .2. CRITICAL APPRAISAL OF FREQUENCY-RESPONSE METHODS FROM A ROOT LOCUS POINT OF VIEW
The inverse Nyquist array (INA) and characteristic locus (CL) techniques are considered here. It is shown that attempts to achieve diagonal dominance, a feature necessary for the application of the INA, may on certain occasions lead to infinite zeros of higher order and thus may severely curtail the system gain margins. The alignment of the characteristic directions at high frequencies, used by the CL on the other hand for the reduction of the misalignment angles, is shown to have a beneficial effect on the structure of the projected Markov parameters. Insight gained by such an appraisal reinforces the belief that root locus and frequency response methods used in a complementary manner may lead to a hybrid design philosophy which is more flexible and effective than either of the two approaches applied separately
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