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In order to improve the effect of injection–production coupling development to improve crude oil recovery in complex fault-block reservoirs, we carried out a physical simulation experiment based on a sandpack model of transforming water-driven development into injection–production coupling development and quantitatively evaluated the influence of rounds of injection pressure coupling on the crude oil mobilization in reservoirs with different permeability levels and on oil recovery. Meanwhile, the characteristics of residual oil were studied via a numerical simulation method. The mechanism of increased oil production via injection–production coupling development was revealed by analyzing the water and oil contents, formation pressure, and streamline fields through the establishment of mechanism models. The results of the physical experiment show that injection–production coupling can improve the recovery effect of medium- and low-permeability reservoirs by 55.66%. With an increase in the injection pressure, the oil recovery percentage of the low-permeability sandpack model at 20 MPa is 100%, and this study finds that injection–production coupling is the main way to develop the recoverable oil in a low-permeability reservoir. The numerical simulation results show that among the four remaining oil distribution types (interwell-enriched, low-permeability zone-enriched, well network imperfection, and mismatch between injection and production), the interwell-enriched type of the remaining oil reserves accounts for the highest proportion (48.52%). The simulation results of the mechanism model show that water-driven development easily leads to streamline solidification, resulting in ineffective circulation of the injected water. Compared with conventional water-driven development, the pressure propagation range is significantly increased in injection–production coupling development. The reservoir streamline distribution is more continuous and uniform, and the flooding wave is wider in volume and range. This research provides a theoretical basis for the injection–production coupling technology policy in complex fault-block reservoirs. [ABSTRACT FROM AUTHOR]

Background: The widespread use and misuse of antimicrobials are the major driving factor for antimicrobial resistance (AMR) that threatens the health of human beings globally. Thus, monitoring antimicrobial consumption at national level is crucial to prevent and contain AMR. Nevertheless, there is no well-established system for recording and reporting of antimicrobial consumption in Ethiopia. Hence, the national antimicrobial consumption survey was conducted to generate evidence for decision-making on the appropriate use of antimicrobials in Ethiopia and tackle AMR. Methods: All imported and locally manufactured antimicrobials from 2017 to 2019 were from the Ethiopian Food and Drug Authority and local manufacturers database, respectively. Data were collected and analyzed descriptively in accordance with the World Health Organization (WHO) Anatomical Therapeutic Chemical (ATC) and defined daily doses (DDD) classification and methodology. Results: The average DDD/1,000 inhabitants for all antimicrobials was 15.36. The DDD/1,000 inhabitants fell down sharply from 37.03 in 2017 to 4.30 in 2018, before slightly rising to 4.75 in 2019. The majority of the consumed antimicrobials were comprised of oral antimicrobials (98.6%), while parenteral antimicrobials made up 1.4%. Tetracyclines (35.81%), fluoroquinolones (20.19%), macrolides (13.92%), antiretrovirals (10.57%), and cephalosporins (9.63%) were the most frequently consumed classes of antimicrobials during the three years period. About 75.83% of the consumed antimicrobials fall under the WHO AWaRe classification and 67.87% of antimicrobial consumption was from the WHO Access class medications, with Watch and Reserve classes accounting for 32.13% and <1%, respectively. Similarly, about 86.90% of the antimicrobials fall under the Ethiopian AWaRe classification, with Access, Watch, and Reserve accounting for 87.73%, 12.26%, and <1%, respectively. Conclusion: Due to the peculiarities of our settings, our findings may have some similarities and differences with similar studies from other countries. Hence, we recommend for all concerned bodies to work collaboratively to improve monitoring of antimicrobial consumption at different levels of the Ethiopian healthcare tier system. Future work is necessary to establish a strong system of reporting of antimicrobial consumption patterns in Ethiopia. [ABSTRACT FROM AUTHOR]

The western Baltic Sea cod (WBC) stock is at historically low levels, mainly attributed to high fishing pressure and low recruitment. Stable stock assessment metrics suggested recovery potential, given appropriate fisheries management measures. However, changing environmental conditions violate stability assumptions, may negatively affect WBC, and challenge the resource management. The present study explored 42 years of changes in WBC biological parameters. WBC body condition gradually decreased over the last decades for juveniles and adults, with a rapid decrease in recent years when a single cohort dominated the overfished stock. The hepato-somatic index and the muscle weight decreased by 50% and 10% in the last 10 years, respectively, suggesting severely decreasing energy reserves and productivity. The changes in energy reserves were associated with changes in environmental conditions (increase in bottom water temperature, expansion of hypoxic areas during late summer/autumn), and changes in diet composition (less herring). A key bottleneck is the warming and longer-lasting summer period when WBC, trapped between warmed shallow waters and hypoxic deeper waters, have to mobilize energy reserves to account for reduced feeding opportunities and thermal stress. Our results suggest that stock recovery is unlikely to happen by fisheries management alone if environmental trajectories remain unchanged. [ABSTRACT FROM AUTHOR]

This paper proposes a comprehensive methodology for determining the converter droop settings to ensure the voltage security in a multi-terminal direct current (MTDC) grid. The novelty lies in the introduction of the concept of over- and under-voltage containment reserves in analogy to the frequency containment reserves in AC systems. This not only gives a distinction of the contribution between the converters in rectifying and inverting modes, but also significantly facilitates the sizing of the necessary amount of reserves within their available headroom capacity of power. In particular, the constraints of converter outages, converter rating, and DC voltage deviations are all taken into account in the design of reserves. The effectiveness of the proposed approach is demonstrated by a contingency power flow analysis algorithm and EMT simulations of a four-terminal MTDC grid. [ABSTRACT FROM AUTHOR]

Global warming is increasing the vulnerability of ecosystems, especially in peninsular Spain. Biosphere Reserves are internationally protected areas that seek to protect biodiversity and, at the same time, promote sustainable development. Evaluating these protected areas is essential to verify environmental changes and establish priorities in their management. In this work, we have studied the time trends of NDVI in the high mountain Biosphere Reserves of Spain from 2001 to 2016 to check if the trend patterns are associated with some environmental variables. Significant differences were found between NDVI trends and high mountain Biosphere Reserves. Firstly, significant positive trends in NDVI were observed when analysing both reserves together. However, significant differences were found between the two reserves. The Ordesa-Viñamala Reserve shows higher positive NDVI trends and lower negative trends, while this pattern is reversed in Sierra Nevada. We observed how the fluctuations in temperature and drought due to climate change have already negatively affected the Mediterranean reserve (Sierra Nevada). In contrast, the alpine reserve (Ordesa-Viñamala) maintains positive NDVI trends. This study helps to close the gap in information related to Biosphere Reserves, which gives value to the work that is being carried out by the local communities that make up them, generating statistically significant results that Biosphere Reserves are protected areas that help us understand how to manage and govern socioecological systems sustainably. • The study assesses NDVI trend in the Spanish high mountain Biosphere Reserves. • We analysis the association between NDVI trends and environmental variables. • Significant differences in NDVI trend frequency found between the reserves. • Climate change is having effects on reserves NDVI trends. • Trend data is key to ensuring reserves take into account in political decisions. [ABSTRACT FROM AUTHOR]

The complex pattern of gold production in Canada, which differs from the classic Hubbert´s curve, is modeled, and a short-term forecast is made, via the Fundamental Equation of Mineral Production (FEMP). For intervals of time with a variable production to reserves ratio, a discrete piecewise version of the equation updates the reserves and the Production to Reserves Ratio (PRR) by units of time. These piecewise linear portions of the PRR correspond to sub-cycles of rising and declining production embedded in the overall history of production. This version of the FEMP allows modelling of any pattern of mineral production at a universal range of scales. The Hubbert´s linearization indicates the official account of reserves underestimates the real amount of gold resources in Canada. The equivalence between the Hubbert's formula and the FEMP is introduced. The Hubbert curve is shown as a case study of the Fundamental Equation, featured as the product of a quadratic function of the cumulative production and a rational function of the PRR with time. The forecast for Canada's current gold production illustrates the metal output is about to peak with an all-time record high in the near future, unless new findings or influential global economic factors are introduced (i.e., a sharp and sustained growth of gold demand from regional markets), allowing an increase of the slope of the linear function featured by the PRR of the FEMP-based model. [ABSTRACT FROM AUTHOR]

The article describes a method for estimating the U.S. government's overall programmatic credit risk exposure that recognizes the covariance across its guarantee programs. The government is urged to have a capital reserve for covering aggregate losses that is lower than the sum of the capital reserves appropriate for each separate guarantee program. Also presented is evidence of loss distributions of government-sponsored enterprises (GSEs) in the context of Fannie Mae and Freddie Mac.

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]

Why have emerging market economies (EMEs) been stockpiling international reserves? We find that motives have varied over time; vulnerability to current account shocks was relatively important in the 1980s but, as EMEs became more financially integrated, factors related to the magnitude of potential capital outflows gained importance. Reserve accumulation as a by-product of undervalued currencies has also become more important since the Asian crisis. Correspondingly, using quantile regressions, we find that the reason for holding reserves varies according to the country's position in the global reserves distribution. High-reserve holders, who tend to be more financially integrated, are motivated by insurance against capital account rather than current account shocks and are more sensitive to the cost of holding reserves than are low-reserve holders. Currency undervaluation is a significant determinant across the reserves distribution, albeit for different reasons. [ABSTRACT FROM AUTHOR]

China is both a major trading partner of the United States and the largest official holder of U.S. assets in the world. The value of Chinese foreign exchange reserves peaked at just over $4 trillion in June 2014 but has since declined to $3.19 trillion (as of August 2016). This very large decline in foreign exchange reserves is unprecedented, and some analysts have speculated that continued sales of these (mostly U.S.) assets might significantly impact the U.S. and global economies. This article explains the reasons for this large decline in official assets, China's available policy choices, and how these choices could affect the U.S. economy. [ABSTRACT FROM AUTHOR]

We present evidence from 260,000 online auctions of second-hand cars to identify the impact of public reserve prices on auction outcomes. We exploit multiple discontinuities in the relationship between reserve prices and vehicle characteristics to present causal regression-discontinuity estimates of reserve price impacts. We find an increase in reserve price decreases the number of bidders, increases the likelihood the object remains unsold, and increases expected revenue conditional on sale. We then combine these estimates to calibrate the reserve price effect on the auctioneer's ex ante expected revenue. This reveals the auctioneer's reserve price policy to be locally optimal. ( JEL D44, L11, L62) [ABSTRACT FROM AUTHOR]

Previous literature believes that a commercial depreciation is associated with higher financial premium and more depletion of foreign reserves. This study re-investigates this belief. Analytical results indicate that a commercial depreciation with higher financial premium and more depletion of foreign reserves depend on the combined influences of the conditions that individuals are impatient as well as foreign interest rates are bigger than time preference rates rather than only policies of commercial depreciation. Non-distortion taxation does not solve the balance-of-payments difficulties. An exact negative relationship between foreign reserves and the financial premium cannot be found. [ABSTRACT FROM AUTHOR]

The article focuses on the rejection of the idea of implementing trillion-dollar coin idea by the U.S. Department of the Treasury and the Federal Reserve to avoid the debt limit in the U.S. It informs that the U.S. government bonds issued by the Treasury aimed to pay for health care are not debt. It also informs that printing of money means to create reserves.

This article examines the interaction between the emerging and traditional powers in global governance reform, and asks whether we are heading towards an international financial system that is more fragmented, where power is more diffused and national and regional arrangements play a more prominent role, at the expense of global multilateral institutions. It begins with a brief discussion of the global systemic and country-specific factors that motivate Brazil, China and other emerging countries to accumulate large currency reserves. We find that national arrangements for managing financial and currency crises will continue to hold sway for emerging countries in the wake of the global crisis. However, the actual capacity of regional arrangements in managing future financial crises is uncertain, and the significance of regional alternatives in the emerging architecture should not be overstated. The real capacity of East Asian regional arrangements to manage financial crises, payments problems or currency attacks is still untested, and key thresholds in multilateralization still lie ahead. In South America, multilateral lender-of-last-resort support inside the region is largely confined to the sub-regional level and is limited by Brazil's reticence. Enduring reliance on bilateral measures for financial crisis management is noted. Where there has been progress in regional solutions, since the global crisis, has been in the role of regional development banks in providing financing for developing countries to enact counter-cyclical policies. Such support also provides insulation for states in the region against the contagion effects of international financial crisis. We are in the midst of transitioning to a more diverse and multi-tiered global financial and monetary system. A reformed IMF could have a role to play in addressing global imbalances and encouraging a shift from national reserves to collective insurance, however, it would be preconditioned by significant shifts in the policy, lending operations, and internal governance of the Fund, and willingness among the G20 to strike a new consensus on how to deal with imbalances, and new accommodation on acceptable reserve levels. [ABSTRACT FROM AUTHOR]

The buildup of reserves in the US. banking system during the financial crisis has fueled concerns that the Federal Reserve's policies may have failed to stimulate the flow of credit in the economy: banks, it appears, are amassing funds rather than lending them out. However, a careful examination of the balance sheet effects of central bank actions shows that the high level of reserves is simply a by-product of the Fed's new lending facilities and asset purchase programs. The total quantity of reserves in the banking system reflects the scale of the Fed's policy initiatives, but conveys no information about the initiatives' effects on bank lending or on the economy more broadly. [ABSTRACT FROM AUTHOR]

In this paper, we consider an insurance company whose surplus (reserve) is modeled by a jump diffusion risk process. The insurance company can invest part of its surplus in n risky assets and purchase proportional reinsurance for claims. Our main goal is to find an optimal investment and proportional reinsurance policy which minimizes the ruin probability. We apply stochastic control theory to solve this problem. We obtain the closed form expression for the minimal ruin probability, optimal investment and proportional reinsurance policy. We find that the minimal ruin probability satisfies the Lundberg equality. We also investigate the effects of the diffusion volatility parameter, the market price of risk and the correlation coefficient on the minimal ruin probability, optimal investment and proportional reinsurance policy through numerical calculations. [ABSTRACT FROM AUTHOR]

This paper uses binary classification trees (BCTs) to predict capital account crises. BCTs successively compare candidate variables and thresholds to split the data into two subsamples, allowing for a large number of indicators to be considered and complex interactions to emerge in a way that standard regressions cannot easily replicate. We identify a robust leading indicator role for three variables (international reserves, current account balance, and short-term external debt) as well as a reserve cover measure that combines them. External indebtedness and domestic GDP growth forecasts are also important predictors of vulnerability. Out of sample, we were able to capture some of the main emerging market crises with relatively few false alarms but the overall out-of-sample performance of our forecasts was mixed. Global cyclical variables help explain vulnerability to crises but they are difficult to predict and, therefore, are of limited use for forecasting purposes. [ABSTRACT FROM AUTHOR]

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]

The article discusses the startling emergence of the Deutsche Mark (DM), the most stable German currency for more than a generation, from 1968-1969 wherein speculators and small savers across Western Europe raced to exchange their currencies for the Deutsche Mark in Germany. The reserves of West Germany's central bank, the Bundesbank, has increased by DM 9.4 million in the first three weeks of November 1968 with DM 7.3 billion arriving in just three days of trading. It also examines the learning curve of DM to give way to a more cooperative understanding of the international monetary system. However, the Social Democrats' vision prevailed the cost of awakening expectations among West German workers, which would not easily be satisfied.

This paper provides a simple, quantitative, net-worth-based approach to assessing the need for central bank capital. It derives a concept of "core capital" (a function of the central bank's operating expenditures and the carrying cost of its international reserves) as the minimum capital needed by a central bank to ensure the credibility of its inflation target. The approach is illustrated with the published accounts of three loss-making central banks and selected accounting entries for a broader sample of central banks. Policy implications are explored. In particular, the paper argues that central bank capitalizations cannot be automatic and require instead a broad policy debate. [ABSTRACT FROM AUTHOR]

Focuses on the economic cooperation between India and the United Arab Emirates in the 1990s. Maintenance of a high level of per capita income by United Arab Emirates; Amount of gross international reserves of India; Contribution of the oil sector to the UAE's gross domestic product.

The article starts with Haslag's (1998) model of the bank's demand for reserves and reformulates it with a cash-in-advance approach for both financial intermediary and consumer. This gives a demand for a base of cash plus reserves that is not sensitive to who gets the inflation tax transfer. It extends the model to formulate a demand for demand deposits, yielding an Mi-type demand, and then includes exchange credit, yielding an M2-type demand. Based on the comparative statics of the model, it provides an interpretation of the evidence on monetary aggregates. This explanation relies on the nominal interest as well as technology factors of the banking sector. [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]

Argues that reserve requirement ratio changes should not be viewed simply as a tool for monetary policy or as a tool used to directly alter the liquidity of financial institutions in the U.S. Criticism of the notion that higher reserve requirements lead to greater safety and lower default risk for depository institutions; Evidence on the 1992 reserve requirement ration changes and perceived bank safety; Relationship between reserve requirement changes and monetary policy.

Focuses on the controversy concerning the implementation of the fractional reserve banking in Austria. Advantages and disadvantages of fractional reserve banking; Reasons behind the rejection of fractional reserve banking; Implications of the fractional reserve banking for business enterprises.

The frequent best practice for managing large low-grade run-of-mine (ROM) stockpiles is to average the entire stockpile to only one grade. Modern ore control and mineral processing procedures need better precision. Low-precision models hinder the ability to create a digital mine-to-mill model and optimize the holistic mining process. Prior to processing, poorly characterized stockpiles are often drilled and sampled, despite there being no geological reason for relationships between samples to exist. Stockpile management is also influenced by reserve accounting and lacks a common operational workflow. This paper provides a review of base and precious metal run-of-mine (ROM) pre-crusher stockpiles in the mining industry, and demonstrates how to build a spatial model of a large long-term stockpile using fleet management system (FMS) data and geostatistical code in Python and R Studio. We demonstrate a framework for modelling a stockpile believed to be readily workable for most modern mines through use of established geostatistical modelling techniques applied to the type of data generated in a FMS. In the method presented, each bench of the stockpile is modeled as its own geological domain. Size of dump loads is assumed to contain the same volume of material and grade values that match those of the grade data tracked in the FMS. Despite the limitations of these inputs, existing interpolation techniques can lead to increased understanding of the grade distribution within stockpiles. Using the framework demonstrated in this paper, engineers and stockpile managers will be able to leverage operational data into valuable insight for empowered decision making and smoother operations. [ABSTRACT FROM AUTHOR]

En a series of papers, Taylor (1971, 1977, 1979) has proposed a theoretical model of Credit Union behavior emphasizing their non-profit and cooperative nature. Taylor (1979) represents the model in its most developed form. In this note his work is surveyed and a modification is proposed, namely the incorporation of current period endogenous reserve accumulation, which is very important in practice and which, it is suggested, fills a significant gap and makes his model more satisfactory as a representation of credit union behaviour in periods of asset growth or decline. [ABSTRACT FROM AUTHOR]

The effects of federal deficits on Federal Reserve behavior as proxied by changes in the growth rate of the monetary base are analyzed in this study. Multivariate Granger-causality tests are employed in the analysis. The deficit measure that is the focus of the analysis is the change in the real market value of privately held federal debt. The tests indicate that the deficit Granger causes the monetary base. Additionally, concerns for financial market stability, real output, and exchange rate movements in the period of floating rates also affect Federal Reserve behavior. [ABSTRACT FROM AUTHOR]

Describes and constructs a measure of changes in required reserves caused by changes in reserve requirement ratios for the United States from 1929 through 1993. History of adjustment factors; Construction of reserve step index; Comparison of reserve step index (RS) and Saint Louis Federal Reserve Bank's Reserve Adjustment Measure (RAM). INSET: Frost's logarithmic adjustment factor..

The article summarizes the experiences of Canada, Japan and Sweden regarding the accumulation of trust fund reserves and the investment of those reserves. Canada has universal pension program Old-Age Security which provides coverage for all residents, and the employment-related pension program Canada Pension Plan. In 1985, the two major social security programs in Japan, the Employees' Pension Insurance and the National Pension Insurance were combined in one system.

With the depletion of traditional energy resources, the share of heavy-oil production has been increasing recently. According to some estimates, their reserves account for 80% of the world's oil resources. Costs for extraction of heavy oil and natural bitumen are 3–4 times higher than the costs of extracting light oil, which is due not only to higher density and viscosity indicators but also to insufficient development of equipment and technologies for the extraction, transportation, and processing of such oils. Currently, a single pipeline system is used to pump both light and heavy oil. Therefore, it is necessary to take into account the features of the heavy-oil pumping mode. This paper presents mathematical models of heavy-oil flow in oil-field pipelines. The rheological properties of several heavy-oil samples were determined by experiments. The dependencies obtained were used as input data for a simulation model using computational fluid dynamics (CFD) methods. The modeling condition investigates the range of shear rates up to 300 s−1. At the same time, results up to 30 s−1 are considered in the developed computational models. The methodology of the research is, thus, based on a CFD approach with experimental confirmation of the results obtained. The proposed rheological flow model for heavy oil reflects the dynamics of the internal structural transformation during petroleum transportation. The validity of the model is confirmed by a comparison between the theoretical and the obtained experimental results. The results of the conducted research can be considered during the selection of heavy-oil treatment techniques for its efficient transportation. [ABSTRACT FROM AUTHOR]