Villisca Municipal Power Plant, Independent Auditor's Reports Financial Statements and Supplemental Information Schedule of Findings, December 31, 2003

Other Audit Report - Utilities

Power Comic Reader : Lector de comics para plataforma iOS

Lector de comics para plataforma iOS para dispositivos iPad.

Interplay of spectral efficiency, power and doppler spectrum for reference-signal-assisted wireless communication

Expressions relating spectral efficiency, power, and Doppler spectrum, are derived for Rayleigh-faded wireless channels with Gaussian signal transmission. No side information on the state of the channel is assumed at the receiver. Rather, periodic reference signals are postulated in accordance with the functioning of most wireless systems. The analysis relies on a well-established lower bound, generally tight and asymptotically exact at low SNR. In contrast with most previous studies, which relied on block-fading channel models, a continuous-fading model is adopted. This embeds the Doppler spectrum directly in the derived expressions, imbuing them with practical significance. Closed-form relationships are obtained for the popular Clarke-Jakes spectrum and informative expansions, valid for arbitrary spectra, are found for the low- and high-power regimes. While the paper focuses on scalar channels, the extension to multiantenna settings is also discussed.

Optimum power allocation for parallel Gaussian channels with arbitrary input distributions

The mutual information of independent parallel Gaussian-noise channels is maximized, under an average power constraint, by independent Gaussian inputs whose power is allocated according to the waterfilling policy. In practice, discrete signalling constellations with limited peak-to-average ratios (m-PSK, m-QAM, etc) are used in lieu of the ideal Gaussian signals. This paper gives the power allocation policy that maximizes the mutual information over parallel channels with arbitrary input distributions. Such policy admits a graphical interpretation, referred to as mercury/waterfilling, which generalizes the waterfilling solution and allows retaining some of its intuition. The relationship between mutual information of Gaussian channels and nonlinear minimum mean-square error proves key to solving the power allocation problem.

High-SNR power offset in multiantenna communication

The analysis of the multiantenna capacity in the high-SNR regime has hitherto focused on the high-SNR slope (or maximum multiplexing gain), which quantifies the multiplicative increase as function of the number of antennas. This traditional characterization is unable to assess the impact of prominent channel features since, for a majority of channels, the slope equals the minimum of the number of transmit and receive antennas. Furthermore, a characterization based solely on the slope captures only the scaling but it has no notion of the power required for a certain capacity. This paper advocates a more refined characterization whereby, as function of SNRjdB, the high-SNR capacity is expanded as an affine function where the impact of channel features such as antenna correlation, unfaded components, etc, resides in the zero-order term or power offset. The power offset, for which we find insightful closed-form expressions, is shown to play a chief role for SNR levels of practical interest.

Optimum power allocation for multiuser OFDM with arbitrary signal constellations

This paper formulates power allocation policies that maximize the region of mutual informationsachievable in multiuser downlink OFDM channels. Arbitrary partitioning ofthe available tones among users and arbitrary modulation formats, possibly different forevery user, are considered. Two distinct policies are derived, respectively for slow fadingchannels tracked instantaneously by the transmitter and for fast fading channels knownonly statistically thereby. With instantaneous channel tracking, the solution adopts theform of a multiuser mercury/waterfilling procedure that generalizes the single-user mercury/waterfilling introduced in [1, 2]. With only statistical channel information, in contrast,the mercury/waterfilling interpretation is lost. For both policies, a number of limitingregimes are explored and illustrative examples are provided.

Per-antenna rate and power control for MIMO layered architectures in the low- and high-power regimes

In a MIMO layered architecture, several codewordsare transmitted from a multiplicity of antennas. Although thespectral efficiency is maximized if the rates of these codewordsare separately controlled, the feedback rate within the linkadaptation loop is reduced if they are constrained to be identical.This poses a direct tradeoff between performance andfeedback overhead. This paper provides analytical expressionsthat quantify the difference in spectral efficiency between bothapproaches for arbitrary numbers of antennas. Specifically, thecharacterization takes place in the realm of the low- and highpowerregimes via expansions that are shown to have a widerange of validity.In addition, the possibility of adjusting the transmit powerof each codeword individually is considered as an alternative tothe separate control of their rates. Power allocation, however,turns out to be inferior to rate control within the context of thisproblem.

The Outlook for Asian Dairy Markets: The Role of Demographics, Income, and Prices, June 2005

The paper first presents a 10-year outlook for major Asian dairy markets (China, India, Indonesia, Japan, South Korea, Malaysia, the Philippines, Thailand, and Vietnam) based on a world dairy model. Then, using Heien and Wessells’s technique, dairy product consumption growth is decomposed into contributions generated by income growth, population growth, price change, and urbanization and these contributions are quantified. Using the world dairy model, the paper also analyzes the impacts of alternative assumptions of higher income levels and technology development in Asia on Asian dairy consumptions and world dairy prices. The outlook projects that Asian dairy consumption will continue to grow strongly in the next decade. The consumption decomposition suggests that the growth would be mostly driven by income and population growth and, as a result, would raise world dairy prices. The simulation results show that technology improvement in Asian countries would dampen world dairy prices and meanwhile boost domestic dairy consumption.

Multilateral Trade and Agricultural Policy Reforms in Sugar Markets, September 2005

We analyze the impact of trade liberalization, removal of production subsidies, and elimination of consumption distortions in world sugar markets using a partial-equilibrium international sugar model calibrated on 2002 market data and current policies. The removal of trade distortions alone induces a 27% price increase while the removal of all trade and production distortions induces a 48% increase by 2011/12 relative to the baseline. Aggregate trade expands moderately, but location of production and trade patterns change substantially. Protectionist OECD countries (the EU, Japan, the US) experience an import expansion or export reduction and significant contraction in production in unfettered markets. Competitive producers in both OECD countries (Australia) and non-OECD countries (Brazil, Cuba), and even some protected producers (Indonesia, Turkey), expand production when all distortions are removed. Consumption distortions have marginal impacts on world markets and location of production. We discuss the significance of these results in the context of mounting pressures to increase market access in highly protected OECD countries and the impact on non-OECD countries.

Spectral efficiency in reference-signal-assisted low-power wireless communication

Expressions relating spectral efficiency, power and Doppler spectrum are derived for low-power Rayleighfaded wireless channels with proper complex signaling. Noside information on the state of the channel is assumed at the receiver. Rather, periodic reference signals are postulated inaccordance with the functioning of most wireless systems. In contrast with most previous studies, which relied on block-fading channel models, a continuous-fading model is adopted. This embeds the Doppler spectrum directly in thederived expressions thereby imbuing them with practical significance.

Dairy Markets in Asia: An Overview of Recent Findings and Implications, September 2005

This paper is an overview of important findings regarding the ongoing evolution of Asian dairy markets based on a series of new economic investigations. These investigations provide systematic empirical foundations for assessing Asian dairy markets with their new consumption patterns, changing industries, and trade prospects under different domestic and trade policy regimes. The findings are drawn from four case studies (China, India, Japan, and Korea), as well as a prospective analysis of future regional patterns of consumption and a policy analysis of trade liberalization of Asian dairy markets. The overview distills the findings of these new investigations and integrates them in the earlier economic literature; it draws policy implications and identifies lessons for countries outside of Asia, especially for emerging exporters in Latin America.

Discourse, knowledge, power and politics: towards critical epistemic discourse analysis

Although both are fundamental terms in the humanities and social sciences, discourse and knowledge have seldom been explicitly related, and even less so in critical discourse studies. After a brief summary of what we know about these relationships in linguistics, psychology, epistemology and the social sciences, with special emphasis on the role of knowledge in the formation of mental models as a basis for discourse, I examine in more detail how a critical study of discourse and knowledge may be articulated in critical discourse studies. Thus, several areas of critical epistemic discourse analysis are identified, and then applied in a study of Tony Blair’s Iraq speech on March 18, 2003, in which he sought to legitimatize his decision to go to war in Iraq with George Bush. The analysis shows the various modes of how knowledge is managed and manipulated of all levels of discourse of this speech.

The dynamics of the Swiss electricity market : three essays

Executive Summary Electricity is crucial for modern societies, thus it is important to understand the behaviour of electricity markets in order to be prepared to face the consequences of policy changes. The Swiss electricity market is now in a transition stage from a public monopoly to a liberalised market and it is undergoing an "emergent" liberalisation - i.e. liberalisation taking place without proper regulation. The withdrawal of nuclear capacity is also being debated. These two possible changes directly affect the mechanisms for capacity expansion. Thus, in this thesis we concentrate on understanding the dynamics of capacity expansion in the Swiss electricity market. A conceptual model to help understand the dynamics of capacity expansion in the Swiss electricity market is developed an explained in the first essay. We identify a potential risk of imports dependence. In the second essay a System Dynamics model, based on the conceptual model, is developed to evaluate the consequences of three scenarios: a nuclear phase-out, the implementation of a policy for avoiding imports dependence, and the combination of both. We conclude that the Swiss market is not well prepared to face unexpected changes of supply and demand, and we identify a risk of imports dependence, mainly in the case of a nuclear phase-out. The third essay focus on the opportunity cost of hydro-storage power generation, one of the main generation sources in Switzerland. We use and extended version of our model to test different policies for assigning an opportunity cost to hydro-storage power generation. We conclude that the preferred policies are different for different market participants and depend on market structure.