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A method of forecasting the balance of electricity consumption of urban development objects, civil purposes using discrete macromodels is proposed. We consider the power supply system (PSS) of the district, which is characterised by power supply from general-purpose power grids, as well as having its own generation of electricity from renewable energy sources (RES). Such a local electric power system (LES) under certain conditions can be operated as an independent balanced electrical facility. For optimal operation of the LES under these conditions, it is necessary to predict its power consumption schedules. The proposed macromodelling method allows to develop deterministic models of power consumption with the required accuracy on the basis of retrospective information without the use of data preprocessing procedures. The solution to the problem of forecasting electricity consumption schedules is simplified by using only basic or deterministic characteristics in the construction of the model. These include fractal properties of PSS load schedules.

In this paper a two-phase pandemic-economic model is proposed, with phase-specific modeling and policy variables – as suggested by the chronicle of pandemic and economic policy developments over the period 2020–2021. In a first phase, the spread of a pandemic disease is the primary concern of authorities, that still also pay attention to economic activity. A dynamic model is introduced, embedding a two-way interaction between an extended epidemic Susceptible-Infected-Recovered (SIR) model and output gap dynamics. In the second phase, posterior to lockdowns when waves fade away, monetary policy becomes the control variable, pursuing again a joint objective, of supporting a non-inflationary recovery without causing significant fatalities. We then use a standard stylized model for the macroeconomy with simplified infection dynamics, that also enter the policy objective. The two phases are thus studied in a regime change model where the control and state variables as well as the objective function are allowed to change across phases. We solve the model over a finite horizon and derive the optimal lockdown or monetary policy path that jointly minimizes pandemic and economic losses. The two-phase finite horizon decision model is empirically calibrated and numerically solved by discretization and optimization methods. In the first phase, albeit with lasting adverse effects on output, lockdown-based control can be effective in reducing infection rates, but less so when starting from a negative output gap. In the second phase, accommodative monetary policy appears to be effective on both fronts, with even an eventual need for a return to tightening as output gap closes and inflation resumes.

Carbon taxes are likely to play a key role in meeting greenhouse gas emission targets that are consistent with the Paris Agreement. In this article, we assess the macroeconomic effects of a carbon tax on the global economy, paying particular attention to the terms-of-trade implications for importers and exporters of fossil fuels. We use a modified version of the National Institute's Global Econometric Model, NiGEM. In the stylized scenarios, all countries and regions impose a permanent and uniform carbon tax immediately. Our simulations show that demand for fossil fuels falls substantially in response to the tax, global (pre-tax) prices of fossil fuels decline, and the tax can raise substantial revenue for the government. The overall impact on GDP growth and inflation in each country depends on the fossil fuel intensity of output, the net losses/gains in terms of trade and the macroeconomic policy reaction. [ABSTRACT FROM AUTHOR]

Modelling for very fast transients (VFTs) requires good knowledge of the behaviour of gas insulated substation (GIS) components when subjected to high frequencies. Modelling usually takes the form of circuit-based insulation coordination type studies, in an effort to determine the maximum overvoltages and waveshapes present around the system. At very high frequencies, standard transmission line modelling assumptions may not be valid. Therefore, the approach to modelling of these transients must be re-evaluated. In this work, the high frequency finite element analysis (FEA) was used to enhance circuit-based models, allowing direct computation of parameters from geometric and material characteristics. Equivalent models that replicate a finite element model’s frequency response for bus-spacer and 90° elbow components were incorporated in alternative transients program-electromagnetic transients program (ATP-EMTP) using a pole-residue equivalent circuit derived following rational fitting using the well-established and robust method of vector fitting (VF). A large model order is often required to represent this frequency dependent behaviour through admittance matrices, leading to increased computational burden. Moreover, while highly accurate models can be derived, the data extracted from finite element solutions can be non-passive, leading to instability when included in time domain simulations. A simple method of improved stability for FEA derived responses along with a method for identification of a minimum required model order for stability of transient simulations is proposed.

Development of “new economies” leading to economies mostly based on knowledge implies the construction of new long-term macroeconometric models. They should incorporate the impacts of new technologies being endogenized, as well as human capital. The paper discusses several issues related to the extension of the notion of production function. They cover first of all the measurement and explanation of total factor productivity (TFP), the role of domestic and foreign R&D expenditures, as well as educational expenditures. The discussion is extended to include proposals to construct new submodels explaining the sections of research and education and also the ICT industries. [ABSTRACT FROM AUTHOR]

The design of MultiProcessor Systems-on-Chip (MPSoC) emphasizes intellectual-property (IP)-based communication-centric approaches. Therefore, for the optimization of the MPSoC interconnect, the designer must develop traffic models that realistically capture the application behavior as executing on the IP core. In this paper, we introduce a Reactive IP Emulator (RIPE) that enables an effective emulation of the IP-core behavior in multiple environments, including bit- and cycle-true simulation. The RIPE is built as a multithreaded abstract instruction-set processor, and it can generate reactive traffic patterns. We compare the RIPE models with cycle-true functional simulation of complex application behavior (task-synchronization, multitasking, and input/output operations). Our results demonstrate high-accuracy and significant speedups. Furthermore, via a case study, we show the potential use of the RIPE in a design-space-exploration context. [ABSTRACT FROM AUTHOR]

In this paper the approach of BRASIL in modelling digitalintegrated circuits is presented. BRASIL consists of a timingsimulator for digital MOS circuits coupled with an algorithmfor circuit simulation. The timing simulation is based upon afast macromodelling approach and the calculation of time-variantRC networks. The circuit simulator takes advantage of structuringthe system of nodal equations. With BRASIL a fast and accuratesimulation of digital circuits, with special regard to the analogbehaviour of highly integrated systems is possible. [ABSTRACT FROM AUTHOR]

Modelling for very fast transients (VFTs) requires good knowledge of the behaviour of gas insulated substation (GIS) components when subjected to high frequencies. Modelling usually takes the form of circuit-based insulation coordination type studies, in an effort to determine the maximum overvoltages and waveshapes present around the system. At very high frequencies, standard transmission line modelling assumptions may not be valid. Therefore, the approach to modelling of these transients must be re-evaluated. In this work, the high frequency finite element analysis (FEA) was used to enhance circuit-based models, allowing direct computation of parameters from geometric and material characteristics. Equivalent models that replicate a finite element model's frequency response for bus-spacer and 90° elbow components were incorporated in alternative transients program-electromagnetic transients program (ATP-EMTP) using a pole-residue equivalent circuit derived following rational fitting using the well-established and robust method of vector fitting (VF). A large model order is often required to represent this frequency dependent behaviour through admittance matrices, leading to increased computational burden. Moreover, while highly accurate models can be derived, the data extracted from finite element solutions can be non-passive, leading to instability when included in time domain simulations. A simple method of improved stability for FEA derived responses along with a method for identification of a minimum required model order for stability of transient simulations is proposed. [ABSTRACT FROM AUTHOR]