Search

Richard Flanagan Question 7 New York. Knopf. 2024. 288 pages. RICHARD FLANAGAN begins his latest book by visiting a coal mine where Japanese soldiers interned his father during World War [...]

The paper proposes a solution to the problem of distributing electricity originating from various sources. In the proposed model, each source has a different cost of acquisition and is characterized by varying energy efficiency factors. Additionally, in the case of renewable sources, the costs of storing energy are taken into consideration as well. This work presents a fair and cost-efficient approach to distributing the demands of energy providers. A model has been developed and verified for the purpose of corroborating the process. [ABSTRACT FROM AUTHOR]

Promoting energy efficiency in iron and steel production provides opportunities for mitigating environmental impacts from this energy-intensive industry. Energy efficiency technologies differ in investment costs, fuel-saving potentials, and environmental performance. Hence the decision-making of the adoption strategy needs to prioritize technological combinations concerning these multi-dimensional objectives. To address this problem, this study proposes a hybrid multi-criteria decision-support model for adopting energy efficiency technologies in the iron and steel industry. The modeling framework integrates a linear programming model that determines the optimal technology adoption rates based on the techno-economic, energy, and environmental performance details and an interactive multi-criteria model analysis tool for diverse modeling environments. A real case study was performed in which a total number of 56 energy efficiency technologies were investigated against various criteria concerning economics, energy, and environmental performances. The results examine the tradeoffs and synergies were examined with regard to seven criteria. A balanced solution shows that a total investment of 13.4 billion USD could save 2.51 Exajoule fuel consumption, cut 67.4 million tons (Mton) CO2 emissions, and reduce air pollution of 1.5 Mton SO2, 1.41 Mton NOx, and 0.86 Mton PM, respectively. The case study demonstrates the effectiveness and applicability of the proposed multi-criteria decision-making support framework. [ABSTRACT FROM AUTHOR]

A method of structured modeling for intergovernmental negotiations for improving European air quality is presented. The model integrates object-oriented programming, simulation methods, multiple-criteria decision-making methods and database management systems.

A formal study of the theoretical performance of switched-capacitor (SC) dc-dc voltage multiplier circuits is given. A question concerning the necessary number of circuit elements to realize a given conversion ratio is addressed. In response to the question the bound on attainable voltage ratio for a given number of capacitors k and the bound on the number of switches required in any circuit configuration have been established. The maximum step-up or step-down ratio is given by the kth Fibonacci number, while the bound on the number of switches required in any SC circuit is 3k - 2. The complete set of attainable dc conversion ratios is found. A canonical circuit realization of the maximum voltage ratio is discussed and illustrative examples are included. Necessary and sufficient conditions for the realizability of a dc conversion ratio are determined and formal proofs are given.

The application of the higher order primal-dual method (HOPDM) to real-life linear programming problems is evaluated. The study also considers the system's application for the Food and Agriculture Project (FAP) at the International Institute for Applied Systems Analysis, particularly for land use and development planning. It is shown that the HOPDM applies particularly well for FAP problems with greater size.

The realization of line and load regulation in switched-capacitor (SC)-based converters is discussed. A duty-cycle control is based on partial charging of the capacitors in the circuit. The influence on the efficiency is pointed out. The use of inductors in SC-based converters is discussed. Index Terms--Efficiency, switched-capacitor (SC) converter, voltage regulation.

Issues relating to decision making problems are examined in detail, with a focus on non-linear models, and applications to intergovernmental negotiations dealing with air quality.

Robustness or insensitivity is a desirable property of decisions; however, most texts on robustness and/or sensitivity analysis do not define it precisely. A broad literature in this field concentrates on robust design of decisions (including robust optimization). This paper focuses on robustness testing, that is, checking whether a design has actually resulted in robust properties of the system if some of basic assumptions are changed. We propose a general framework of such robustness testing and show that robustness is a property of the relation between three (classes of) models: a basic model of the decision situation, a second model of possible perturbations of the first model, and a model of implementation of the decision, optionally taking into account some measurements of the impact of perturbations. Typical approaches to robustness or sensitivity analysis assume tacitly that the first two models can be combined and analyze parameters deviations in one combined model. However, the role of the first two models can be asymmetric if some optimization of the decision is performed on the first model. We extend this framework, intended originally for single criteria (scalar) optimization to multiple criteria (vector) optimization. The proposed approach is illustrated by diverse examples. [ABSTRACT FROM AUTHOR]

Issues relating to the development of decision support systems for problems such as the management of water quality and sustainable development are examined in detail.

BSTRACT: This paper presents the implementation of one element of a decision support system (DSS) for regional water quality management, applied to the Nitra River Basin in Slovakia. A model-based, aspiration-led methodology for multicriteria decision support has been used for the study. Several reusable, modular software tools have been developed and implemented: a problem-specific generator to produce the core part of the mathematical programming model, tools for the generation and interactive modification of multicriteria problems, and a solver for the resulting mixed-integer optimization problem. Provided in the paper are the following: a complete formulation of the mathematical model (including the imbedded water quality model), a summary of the aspiration-reservation-led multiple criteria optimization approach applied to decision support, and an overview of results that illustrate the applied approach and provide some interesting insights to the case study. [ABSTRACT FROM AUTHOR]

The realization of line and load regulation in switched-capacitor (SC)-based converters is discussed. A duty-cycle control is based on partial charging of the capacitors in the circuit. The influence on the efficiency is pointed out. The use of inductors in SC-based converters is discussed. [ABSTRACT FROM AUTHOR]

There is a growing interest in the power-to-liquid (PTL) technology, especially in using electricity from renewable sources to generate H 2 , and then coupled with CO 2 captured from various sources (e.g., coal-fired power plants) to produce liquid fuels (e.g., gasoline). As a negative emission technology, the product of PTL could be used in the internal combustion engine vehicles (ICEV) and thus cause limited shifts in current energy infrastructure and automobile industry compared with the electrification paths. However, it is still unknown whether the PTL technology could be adopted and contributed to reaching carbon neutrality in China's transportation sector. Against this, a novel model of the liquid fuel supply system considering multiple low-emission technologies, including PTL, is constructed to evaluate PTL's potential contribution and cost to the carbon-neutral target of China's transportation sector. Results show the following: First, PTL can achieve a maximum 93% carbon emission reduction compared with oil to liquid (OTL). Second, the most cost-effective deployment strategy for PTL is to increase the total cost by 5–10%. Third, international oil prices and technology-learning effects have significant impacts on the diffusion of PTL. Fourth, PTL can be a supplementary solution to achieve net-zero emissions in the transportation sector. • We construct a liquid fuel supply system model under the MESSAGE ix framework. • We assess whether PTL (power-to-liquid) will appear in the liquid fuel systems. • We analyse how oil price and technological learning rate affect the diffusion of PTL. • PTL is a supplementary solution to achieve net-zero emissions in the transportation sector. [ABSTRACT FROM AUTHOR]