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The AquaCrop simulation model, originally designed for annual crops, is expanded here to simulate alfalfa, a perennial forage crop. A new routine was added to the model to mimic the assimilate partitioning between above and below-ground plant parts to account for the utilization of reserves in Spring and for their storage in the Fall. The simulation of the transfer of assimilates requires only three extra crop parameters which makes the model also easy to calibrate. To evaluate the model, yield data collected in Louvain-La-Neuve (Belgium), Isparta (Turkey), and Ottawa (Canada) for different alfalfa cultivars, various years and field and irrigation management strategies were used. To assess the accuracy and robustness of the simple assimilate remobilization process, simulations were run for the three different environments with a common set of crop parameters which were parameterized. The dispersion between the observed and simulated cumulative dry above-ground biomass during the growing cycle was small (r² = 0.97; nRMSE = 11%; Nash-Sutcliffe model EF = 0.97), and a systematic over- or underestimation by the model was not observed (Willmott's index of agreement, d = 0.99). When evaluating the goodness of fit of the 81 individual harvest events, the results were still very satisfactory although the nRMSE doubled. The simulations indicated that the AquaCrop model adapted to perennial crops and with a novel storage-remobilization routine, could predict well alfalfa yields in various climates and environments, with and without water and fertility stress, and for three different alfalfa cultivars. • The AquaCrop simulation model is expanded to simulate perennial forage crops. • A simple routine describes the transfer of assimilates between the above ground biomass and the below-ground storage organs. • Variations in partitioning along the season was simulated by increasing or reducing the crop water productivity. • Simulations were run with a common set of crop parameters for different years, alfalfa cultivars, climates, and environments. • The simulations indicated that AquaCrop can well predict the total yield of alfalfa that can be expected in various environments. [ABSTRACT FROM AUTHOR]

In recent years, numerous research works have been reported on the flexural response of aluminium alloy tubular cross-sections. However, studies on monosymmetric cross-sections and particularly channel (C-) sections are limited, albeit their increased usage in structural applications. This paper aims to address this knowledge gap providing an improved understanding about the minor axis bending behaviour of C-sections through an experimental and numerical investigation. In total 14 specimens made from 6082-T6 heat-treated aluminium alloy were subjected to four-point bending. Tensile coupon tests were also performed to determine the mechanical properties of the examined aluminium alloy. The obtained experimental results are analysed and discussed. A series of geometrically and materially nonlinear analyses were also carried out to study the flexural performance of C-sections in two aluminium alloys and two bending orientations over a range of cross-sectional aspect ratios and slendernesses. The experimental and numerical results are utilised to assess the European design standards. The applicability of the Continuous Strength Method and the Direct Strength Method is also evaluated. An alternative design method based on the plastic effective width concept is proposed for slender C-sections subjected to minor axis bending. This method accounts for the inelastic reserve capacity which is in accordance with the experimental and numerical observations. • Flexural response of aluminium alloy C-sections is investigated. • 14 four-point minor axis bending tests are reported. • A wide parametric study is carried out. • Current codified design provisions are assessed. • The plastic effective width method is proposed for slender C-sections under minor axis bending. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes a novel financing scheme, reserve financing, for government infrastructure investment in China. A two-sector open economy model explores the consequences and policy implications of a surge in infrastructure investment financed by international reserves. The results show that reserve financing, coupled with a managed float exchange rate system, can maintain the country's fast growth rate while mitigating fiscal pressure on local governments. Productive infrastructure capital stimulates domestic demand, reducing the country's dependence on exports. To promote growth and maintain price stability, three factors are critical: return on infrastructure, swift fiscal adjustment, and rapid infrastructure financing. [Copyright &y& Elsevier]

Abstract: We model a stylized banking system where banks are characterized by the amount of capital, cash reserves and their exposure to the interbank loan market as borrowers as well as lenders. A network of interbank lending is established that is used as a transmission mechanism for the failure of banks through the system. We trigger a potential banking crisis by exogenously failing a bank and investigate the spread of this failure within the banking system. We find the obvious result that the size of the bank initially failing is the dominant factor whether contagion occurs, but for the extent of its spread the characteristics of the network of interbank loans are most important. These results have implications for the regulation of banking systems that are briefly discussed, most notably that a reliance on balance sheet regulations is not sufficient but must be supplemented by considerations for the structure of financial linkages between banks. [Copyright &y& Elsevier]

Abstract: Although the economic literature on the optimal management of bank excess reserves is age-old and large, here we suggest a fresh, more practical approach based on queuing theory. [Copyright &y& Elsevier]

Abstract: Energy companies can adjust the estimation of their reserves. We investigate how these revisions impact on the value of these firms. We analyze 100 revisions in seventeen countries for the period 2000-2010. We use an event study and find that the revisions of energy reserves significantly impact on the market value of the firm. We also discover an asymmetry in this response as the market’s reaction to downward revisions is much larger than that to upward revisions. Furthermore, the response to revisions in Australia, Canada, UK and US is smaller than that in the other 13 countries and the response is smaller in the years with turmoil on the energy markets. [Copyright &y& Elsevier]

Abstract: This paper investigates the relationship between financing constraints and investment–cash flow sensitivities by focusing on cash holdings of firms as the main classification variable to separate firms into financially constrained and unconstrained categories. The idea is that high cash reserves increase the ability of firms to undertake profitable investment opportunities. Our classification is based on an optimal cash model, which helps us identify the firms that deviate significantly from their target cash ratio. We conduct the analysis for an emerging market, before and during a financial crisis to test the hypothesis that the hedging role of cash is more critical in states of the world characterized by high asymmetric information and excessive costs of external finance. The results are in line with our expectations and show that constrained firms exhibit greater investment–cash flow sensitivities than unconstrained firms. Also, there is strong evidence that cash stands as an effective device for firms, mainly during the crisis period. [Copyright &y& Elsevier]

Abstract: Using a small macroeconometric model that examines the determinants of India''s trade and inflation, this paper addresses the effects of a reform policy package similar to those implemented in 1991. Policy simulations using dynamic simulation method compare the responses to devaluation with the responses to tight credit policy. It is shown that the trade balance effects of tight credit policy are more enduring than that of devaluation, conditional on inflation being modelled in an open economy context. The simulations demonstrate that the devaluation actually worsens trade balance and hence devaluation cannot be an option in response to a negative trade shock, whereas the reduction in domestic credit reflecting demand contraction can produce a desirable improvement in the trade balance. [Copyright &y& Elsevier]

This article reconsiders the Hicksian multiplier-accelerator model with the "floor" related to the depreciation on actual capital stock. Through the introduction of the capital variable, a growth trend is created endogenously by the model itself, along with growth rate oscillations around it. The "ceiling" can be dispensed with altogether. As everything is growing in such a model, a variable transformation is introduced to focus relative dynamics of the income growth rate and the actual capital output ratio. [ABSTRACT FROM AUTHOR]

Developing countries’ reserves have increased dramatically in recent years—growing by over 60% since the Asian financial crisis. This paper explores the self-insurance motivation behind this. As a first step, it revisits the literature on international reserve demand. This paper then examines the reserve-holding trends in a sample of 65 developing countries. It seeks to answer the following: Have reserves increased across the board or have these been concentrated in a few countries? If so, does it represent a break in previous policy? At what cost? This paper concludes by briefly examining some policy implications and avenues for future research. [Copyright &y& Elsevier]

• Reserve capacity activation is explicitly modelled for hydropower plants. • A new hybrid stochastic-robust optimization model is formulated. • The column-and-constraint generation technique is used to create extreme scenarios. • The new hybrid model is compared to the standard stochastic and robust formulations. As the penetration of variable renewable power generation increases in power systems around the world, system security is challenged. It is crucial to coordinate the available flexible generating resources, such as hydropower, to meet the need for system balancing. However, reserved capacity on hydropower plants should only be activated if there is sufficient energy or storage capacity to either increase or decrease production. The potential change in production will also affect all reservoirs and plants connected by the cascaded topology. These issues are largely ignored or simplified in hydropower reserve scheduling models. To properly account for the possible activation of reserved capacity, several two-stage model formulations based on stochastic and robust optimization are presented and compared in this paper. The uncertainty in net load deviations due to forecasting errors in renewable power generation is considered the source of reserve capacity activation. The case study based on a real Norwegian watercourse clearly shows the benefit of using any of the two-stage model solutions over the standard deterministic reserve procurement. A novel hybrid stochastic-robust model formulation is presented and shown to efficiently increase the robustness of the solution without notably increasing the reserve procurement cost compared to the stochastic and robust models. [ABSTRACT FROM AUTHOR]

• A chance-constrained DCOPF with non-parametric correlated probabilistic forecasts of DLR and wind power. • The model co-optimizes energy and reserves with typical risk aversion levels of TSOs. • Assuming a normal distribution overestimates the probabilistic forecasts of DLR. • DLR reduces wind power curtailment and dispatch costs in highly congested networks. Compared to Seasonal Line Rating (SLR), Dynamic Line Rating (DLR) allows for higher power flows on overhead transmission lines, depending on the actual weather conditions. Nevertheless, the potential of DLR has to be traded off against the additional uncertainty associated with varying ratings. This paper proposes a DC-Optimal Power Flow (DCOPF) algorithm that accounts for DLR uncertainty by means of Chance-Constraints (CC). The goal is to determine the optimal day-ahead dispatch taking the cost of reserve procurement into account. The key contribution of this paper consists in considering both non-parametric predictive distributions of DLR and the combined wind power uncertainty in the optimization problem. Our results highlight the benefits of DLR in wind-dominated power systems, assuming typical risk aversion levels in the line rating estimation. [ABSTRACT FROM AUTHOR]

Reports on a transcript which highlights the role of technology. Reference to seminar for research library directors; Details of `Digitizing the Reserve Function: Steps Toward Electronic Document Delivery'; Relevant information.