Artículos de revistas: "Medium scale DSGE framework"

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Vitek, Francis, Vitor Gaspar y Tobias Adrian. "A Medium-Scale DSGE Model for the Integrated Policy Framework". IMF Working Papers 2022, n.º 015 (enero de 2022): 1. http://dx.doi.org/10.5089/9781616359706.001.

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Haider, Adnan y Safdar Ullah Khan. "A Small Open Economy DSGE Model for Pakistan". Pakistan Development Review 47, n.º 4II (1 de diciembre de 2008): 963–1008. http://dx.doi.org/10.30541/v47i4iipp.963-1008.

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In recent years there has been a growing interest in academics, international policy institutions and central banks1 in developing small-to-medium, even large-scale, open economy macroeconomic models called Dynamic Stochastic General Equilibrium (DSGE) models based on new-Keynesian framework.2 The term DSGE was originally used by Kydland and Prescott (1982) in their seminal contribution on Real Business Cycle (RBC) model. The RBC model is based on neoclassical framework with micro-founded optimisation behaviour of economic agents with flexible prices. One of the critical assumptions of this model is that fluctuations of real quantities are caused by real shock only; that is, only stochastic technology or government spending shocks play their role. Later research in DSGE models however included Keynesian short-run macroeconomic features (called nominal rigidities), such as Calvo (1983) type staggered pricing behaviour and Taylor (1980) type wage contracts. Hence this new DSGE modeling framework labeled as new-neoclassical synthesis or new-Keynesian modeling paradigm. 3 This new approach combines micro-foundations of both households and firms optimisation problems and with a large collection of both nominal and real (price/wage) rigidities that provide plausible short-run dynamic macroeconomic fluctuations with a fully articulated description of the monetary policy transmission mechanism; see, for instance, Christiano, et al. (2005) and Smets and Wouters (2003). The key advantage of modern DSGE models, over traditional reduce form macroeconomic models, is that the structural interpretation of their parameters allows to overcome the famous Lucas critique (1976).4 Traditional models contained equations linking variables of interest of explanatory factors such as economic policy variables. One of the uses of these models was therefore to examine how a change in economic policy affected these variables of interest, other things being equal. In using DSGE models for practical purposes and to recommend how central banks and policy institutions should react to the short-run fluctuations, it is necessary to first examine the possible sources,5 as well as to evaluate the degree of nominal and real rigidities present in the economy. In advanced economies, like US and EURO area, it is easy to determine the degree of nominal and real rigidities as these economies are fully documented. In developing economies like Pakistan, where most of economic activities are un-documented (also labeled as informal economy, black economy, or underground economy), it is very difficult to determine the exact degree of nominal and real rigidities present in the economy. However, one can approximate results using own judgments and through well defined survey based methods

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Barthélemy, Jean y Guillaume Cléaud. "TRADE BALANCE AND INFLATION FLUCTUATIONS IN THE EURO AREA". Macroeconomic Dynamics 22, n.º 4 (11 de julio de 2017): 931–60. http://dx.doi.org/10.1017/s1365100516000456.

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We estimate a medium-scale dynamic stochastic general equilibrium (DSGE) model for the euro area in an open-economy framework. The model includes structural trends on all variables, allowing us to estimate on gross data. First, we provide a theoretical balanced growth path consistent with permanent productivity shocks, inflation target changes, and permanent shocks to the openness of the economies. We then define the cycle as the gap between this sustainable trajectory and the gross data. Hence, we can properly deal with persistent deviations of the trade balance. Finally, we find persistent and strong effects from the asymmetric increase of euro-area imports during the last 10 years on domestic inflation. From 2000Q1 to 2008Q4, we estimate the contribution of the imbalanced development of international trade on euro-area inflation to an average of −0.7%, and on nominal interest rate, to an average of −1.4%.

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4

Slobodyan, Sergey y Raf Wouters. "Learning in an estimated medium-scale DSGE model". Journal of Economic Dynamics and Control 36, n.º 1 (enero de 2012): 26–46. http://dx.doi.org/10.1016/j.jedc.2011.01.016.

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5

Ivashchenko, Sergey y Rangan Gupta. "Forecasting using a Nonlinear DSGE Model". Journal of Central Banking Theory and Practice 7, n.º 2 (1 de mayo de 2018): 73–98. http://dx.doi.org/10.2478/jcbtp-2018-0013.

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Abstract A medium-scale nonlinear dynamic stochastic general equilibrium (DSGE) model was estimated (54 variables, 29 state variables, 7 observed variables). The model includes an observed variable for stock market returns. The root-mean square error (RMSE) of the in-sample and out-of-sample forecasts was calculated. The nonlinear DSGE model with measurement errors outperforms AR (1), VAR (1) and the linearised DSGE in terms of the quality of the out-of-sample forecasts. The nonlinear DSGE model without measurement errors is of a quality equal to that of the linearised DSGE model.

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6

ZUBAIRY, SARAH. "ON FISCAL MULTIPLIERS: ESTIMATES FROM A MEDIUM SCALE DSGE MODEL". International Economic Review 55, n.º 1 (22 de enero de 2014): 169–95. http://dx.doi.org/10.1111/iere.12045.

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Chaim, Pedro y Márcio Poletti Laurini. "Data Cloning Estimation and Identification of a Medium-Scale DSGE Model". Stats 6, n.º 1 (24 de diciembre de 2022): 17–29. http://dx.doi.org/10.3390/stats6010002.

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We apply the data cloning method to estimate a medium-scale dynamic stochastic general equilibrium model. The data cloning algorithm is a numerical method that employs replicas of the original sample to approximate the maximum likelihood estimator as the limit of Bayesian simulation-based estimators. We also analyze the identification properties of the model. We measure the individual identification strength of each parameter by observing the posterior volatility of data cloning estimates and access the identification problem globally through the maximum eigenvalue of the posterior data cloning covariance matrix. Our results corroborate existing evidence suggesting that the DSGE model of Smeets and Wouters is only poorly identified. The model displays weak global identification properties, and many of its parameters seem locally ill-identified.

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8

Wang, Rui. "Unconventional Monetary Policy in Japan: Empirical Evidence from Estimated Shadow Rate DSGE Model". Journal of International Commerce, Economics and Policy 10, n.º 02 (junio de 2019): 1950007. http://dx.doi.org/10.1142/s1793993319500078.

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The Zero Lower Bound (ZLB) on short nominal interest rates has imposed serious constraint on stimulating and stabilizing economy of major central banks. Analysis of monetary policy by Dynamic Stochastic General Equilibrium (DSGE) models under the existence of ZLB has also been an important issue from both practical and academic views for central banks and macroeconomists. However, the nonlinearity of ZLB constraint makes linear solution and estimation techniques of DSGE models unreliable and impractical. In many recent empirical works, it has been proved that the shadow rate can be used as an accurate proxy to represent the stance of unconventional monetary policy in the ZLB environment. We use shadow rate to estimate a medium-scale DSGE model based on the theoretical foundation proposed by Wu and Zhang (2016). A shadow rate New Keynesian model (No. w22856). National Bureau of Economic Research, and conduct counterfactual simulation exercises to quantify the macroeconomic effects of unconventional monetary policy implemented by Bank of Japan (BoJ). Compared with the estimation results of pre-ZLB sub-sample (1980Q1–1998Q4), the structural parameters estimated from full-sample (1980Q1–2016Q3) with the shadow rate still have very reasonable values that are consistent with most related medium-scale DSGE literature. The statistical properties of model dynamics implied by two groups of estimation are also very close. Counterfactual simulation shows that without the unconventional monetary policy, macroeconomic variables would have worse performance than their actual realizations.

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Bekiros, Stelios D. y Alessia Paccagnini. "Bayesian forecasting with small and medium scale factor-augmented vector autoregressive DSGE models". Computational Statistics & Data Analysis 71 (marzo de 2014): 298–323. http://dx.doi.org/10.1016/j.csda.2013.09.018.

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Abilov, N. "A Medium-Scale Bayesian DSGE Model for Kazakhstan with Incomplete Exchange Rate Pass-Through". International Economic Journal 35, n.º 4 (2 de octubre de 2021): 486–522. http://dx.doi.org/10.1080/10168737.2021.1999298.

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Slobodyan, Sergey y Raf Wouters. "Learning in a Medium-Scale DSGE Model with Expectations Based on Small Forecasting Models". American Economic Journal: Macroeconomics 4, n.º 2 (1 de abril de 2012): 65–101. http://dx.doi.org/10.1257/mac.4.2.65.

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This paper evaluates the empirical performance of a medium-scale DSGE model with agents forming expectations using small forecasting models updated by the Kalman filter. The adaptive learning model fits the data better than the rational expectations (RE) model. Beliefs about the inflation persistence explain the observed decline in the mean and the volatility of inflation as well as Phillips curve flattening. Learning about inflation results in lower estimates for the persistence of the exogenous shocks that drive price and wage dynamics in the RE version of the model. Expectations based on small forecasting models are closely related to the survey evidence on inflation expectations. (JEL C53, D83, D84, E13, E17, E31)

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Nymoen, Ragnar. "On the Low Degree of Entropy Implied by the Solutions of Modern Macroeconomic Models". Entropy 24, n.º 12 (25 de noviembre de 2022): 1728. http://dx.doi.org/10.3390/e24121728.

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The non-causal (“forward-looking”) solution used routinely in academic macroeconomics may represent a violation of a law of entropy, namely that the direction of time is one way (from the past and towards the present), and that the variance of economic processes increases with time. In order to re-establish a degree of compatibility with the law of entropy, so called hybrid forms are required add-ins to DSGE (Dynamic Stochastic General Equilibrium) models. However, the solution that uses hybrid forms is a particular special case of a causal solutions of autoregressive distributed lags, VARs and recursive and simultaneous equations models well known from empirical macro econometrics. Hence, hybrid forms of small scale DSGE models can be analysed and tested against competing model equations, using an econometric encompassing framework.

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Hirose, Yasuo. "AN ESTIMATED DSGE MODEL WITH A DEFLATION STEADY STATE". Macroeconomic Dynamics 24, n.º 5 (14 de noviembre de 2018): 1151–85. http://dx.doi.org/10.1017/s1365100518000743.

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Benhabib et al. [(2001) Journal of Economic Theory 96, 40–69] argue that there exists a deflation steady state when the zero lower bound on the nominal interest rate is considered in a Taylor-type monetary policy rule. This paper estimates a medium-scale DSGE model with a deflation steady state for the Japanese economy during the period from 1999 to 2013, when the Bank of Japan conducted a zero interest rate policy and the inflation rate was almost always negative. Although the model exhibits equilibrium indeterminacy around the deflation steady state, a set of specific equilibria is selected by Bayesian methods. According to the estimated model, positive shocks to households’ preferences and wage markup, and a negative shock to monetary policy do not necessarily have an inflationary effect, in contrast to a standard model with a targeted-inflation steady state. An economy in the deflation equilibrium could experience unexpected volatility because of sunspot fluctuations, but it turns out that sunspot shocks have a limited effect on Japan’s output fluctuations and rather contribute to stabilizing the economy after the global financial crisis.

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DEW-BECKER, IAN. "Bond Pricing with a Time-Varying Price of Risk in an Estimated Medium-Scale Bayesian DSGE Model". Journal of Money, Credit and Banking 46, n.º 5 (24 de julio de 2014): 837–88. http://dx.doi.org/10.1111/jmcb.12130.

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15

Erceg, Christopher, Andrea Prestipino y Andrea Raffo. "Trade policies and fiscal devaluations". International Finance Discussion Paper 2022, n.º 1347 (22 de junio de 2022): 1–78. http://dx.doi.org/10.17016/ifdp.2022.1347.

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Fiscal devaluations—an increase in import tariffs and export subsidies (IX) or an increase in value-added taxes and payroll subsidies (VP)—have been shown to provide as much stimulus under fixed exchange rates as a currency devaluation. We find that if agents expect policies to be reversed and the tax pass-through is large, VP is contractionary and IX provides a modest boost. In our medium-scale DSGE model, both features are crucial in accounting for Germany’s underperformance in response to VP in 2007. These findings cast doubt on fiscal devaluations as a cyclical stabilization tool when monetary policy is constrained.

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Bilbiie, Florin O., Tommaso Monacelli y Roberto Perotti. "Is Government Spending at the Zero Lower Bound Desirable?" American Economic Journal: Macroeconomics 11, n.º 3 (1 de julio de 2019): 147–73. http://dx.doi.org/10.1257/mac.20150229.

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We build a medium-scale DSGE model and calibrate it to fit the main macroeconomic variables during the US Great Recession. Using it to evaluate the welfare effects of increasing government consumption at the zero lower bound beyond what was actually observed in the data, we reach three main results. First, the increase in government consumption after 2008, albeit small in present value terms, was close to optimal. Second, frontloading the same stimulus would have been welfare-improving. Third, larger welfare effects occur in our model for parameter values implying either large welfare costs of modest recessions (e.g., high consumption curvature), or outright large recessions. (JEL E12, E32, E43, E62, H50)

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Kara, Engin y Leopold von Thadden. "INTEREST RATE EFFECTS OF DEMOGRAPHIC CHANGES IN A NEW KEYNESIAN LIFE-CYCLE FRAMEWORK". Macroeconomic Dynamics 20, n.º 1 (14 de julio de 2014): 120–64. http://dx.doi.org/10.1017/s1365100514000273.

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This paper develops a small-scale DSGE model that embeds a demographic structure within a monetary policy framework. We extend the nonmonetary overlapping-generations model of Gertler and present a small synthesis model that combines the setup of Gertler with a New Keynesian structure, implying that the short-run dynamics related to monetary policy can be compared with that of the standard New Keynesian model. In sum, the model offers a New Keynesian platform that can be used to characterize the response of macroeconomic variables to demographic shocks, similarly to the responses to technology or monetary policy shocks. We offer such characterizations for flexible and sticky price equilibria. Empirically, we calibrate the model to demographic developments projected for the euro area. The main finding is that the projected slowdown in population growth and the increase in longevity contribute slowly over time to a decline in the equilibrium interest rate.

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SAHUC, JEAN-GUILLAUME y FRANK SMETS. "Differences in Interest Rate Policy at the ECB and the Fed: An Investigation with a Medium-Scale DSGE Model". Journal of Money, Credit and Banking 40, n.º 2-3 (marzo de 2008): 505–21. http://dx.doi.org/10.1111/j.1538-4616.2008.00124.x.

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Born, Benjamin y Johannes Pfeifer. "THE NEW KEYNESIAN WAGE PHILLIPS CURVE: CALVO VS. ROTEMBERG". Macroeconomic Dynamics 24, n.º 5 (27 de noviembre de 2018): 1017–41. http://dx.doi.org/10.1017/s1365100518000615.

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We systematically evaluate how to translate a Calvo wage duration into an implied Rotemberg wage adjustment cost parameter in medium-scale New Keynesian DSGE models by making use of the well-known equivalence of the two setups at first order. We consider a wide range of felicity functions and show that the assumed household insurance scheme and the presence of labor taxation greatly matter for this mapping, giving rise to differences of up to one order of magnitude. Our results account for the inclusion of wage indexing, habit formation in consumption, and the presence of fixed costs in production. We also investigate the conditional and unconditional welfare implications of the wage-setting schemes under efficient and distorted steady states.

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Bilbiie, Florin O. "Optimal Forward Guidance". American Economic Journal: Macroeconomics 11, n.º 4 (1 de octubre de 2019): 310–45. http://dx.doi.org/10.1257/mac.20170335.

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Optimal forward guidance is the simple policy of keeping interest rates low for some optimally determined number of periods after the liquidity trap ends and moving to normal-times optimal policy thereafter. I solve for the optimal duration in closed form in a new Keynesian model and show that it is close to fully optimal Ramsey policy. The simple rule “announce a duration of half of the trap’s duration times the disruption” is a good approximation, including in a medium-scale dynamic stochastic general equilibrium (DSGE) model. By anchoring expectations of Delphic agents (who mistake commitment for bad news), the simple rule is also often welfare-preferable to Odyssean commitment. (JEL D84, E12, E43, E52, E56)

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Papageorgiou, Dimitris. "Macroeconomic effects of shocks to import and services sector prices". Economic bulletin, n.º 54 (1 de diciembre de 2021): 7–22. http://dx.doi.org/10.52903/econbull20215401.

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This paper investigates the macroeconomic implications of inflationary shocks that originate from the import and services sectors. The set-up is a medium-scale Dynamic Stochastic General Equilibrium (DSGE) model calibrated for the Greek economy. The results suggest that a temporary increase in import price inflation adversely affects economic activity and drives up domestic inflation. The largest output losses occur in the medium term, since in the short term the adverse effects are dampened by the presence of price rigidities and an import substitution effect that induces expenditure to switch towards domestically produced goods. Additionally, the findings suggest that a temporary increase in the price of the services sector exerts strong inflationary pressures and negatively affects economic activity. Finally, the results show that inflation persistence matters for the effects on the macroeconomy. The more persistent inflation is in imports and the services sector, the larger the output losses.

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Thakkar, Jitesh, Arun Kanda y S. G. Deshmukh. "Supply chain performance measurement framework for small and medium scale enterprises". Benchmarking: An International Journal 16, n.º 5 (28 de agosto de 2009): 702–23. http://dx.doi.org/10.1108/14635770910987878.

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23

Lhuissier, Stéphane. "THE REGIME-SWITCHING VOLATILITY OF EURO AREA BUSINESS CYCLES". Macroeconomic Dynamics 22, n.º 2 (22 de junio de 2017): 426–69. http://dx.doi.org/10.1017/s1365100516000274.

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We document the strong evidence of time variation in the volatility of Euro Area business cycles since 1970. Then we provide the quantitative sources of these changes using a medium-scale DSGE model allowing time variation in structural disturbance variances. We show that (1) the size of different types of shock oscillates, in a synchronized manner, between two regimes over time, with the high-volatility regime prevailing predominantly in the 1970s, sporadically in the 1980s and 1990s, and during the Great Recession; (2) their relative importance remains, however, unchanged across regimes, where neutral technology shocks and marginal efficiency of investment shocks are the dominant sources of business cycle fluctuations; and 3) these investment shocks, which affect the transformation of savings into productive capital, can be interpreted as an indicator of credit conditions.

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Haddar, H. y P. Joly. "Homogenized model for a laminar ferromagnetic medium". Proceedings of the Royal Society of Edinburgh: Section A Mathematics 133, n.º 3 (junio de 2003): 567–98. http://dx.doi.org/10.1017/s0308210500002547.

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We study the homogenization of ferromagnetic equations with periodic coefficients in space dimension 2. The obtained nonlinear homogenized law can only be written using a two-scale framework, which couples microscopic and macroscopic scales. It also involves corrector terms, at the microscopic scale, in the form of pseudo-differential operators. We prove the L2 two-scale strong convergence in the laminar case (one-dimensional periodicity).

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Gandhi, Vaibhav, Parag Paija, Tarang Joshi, Jay Vekariya, Priyank Zaveri y Vimal N. Patel. "A Framework to Create Employability Skills for Small and Medium Scale Industry". Journal of Engineering Education Transformations 34 (31 de enero de 2021): 628. http://dx.doi.org/10.16920/jeet/2021/v34i0/157233.

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Mohapatra, Sanjay y Anuj Jindal. "Green IT framework for small and medium scale Indian IT services companies". International Journal of Green Economics 4, n.º 3 (2010): 245. http://dx.doi.org/10.1504/ijge.2010.037526.

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27

Wang, Rui. "Evaluating the Unconventional Monetary Policy of the Bank of Japan: A DSGE Approach". Journal of Risk and Financial Management 14, n.º 6 (7 de junio de 2021): 253. http://dx.doi.org/10.3390/jrfm14060253.

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When the nominal interest rate reaches the zero lower bound (ZLB), a conventional monetary policy, namely, the adjustment of short-term interest rate, may become impractical and ineffective for central banks. Therefore, quantitative easing (QE) is one of the few available policy options of central banks for stimulating the economy and dealing with deflationary pressure. Since February 1999, the Bank of Japan (BoJ) has conducted several unconventional monetary policy programs. Considering the scarce research in this field from a structural macroeconomic model approach, a medium-scale New Keynesian DSGE model with government bonds of different maturities was developed to check the portfolio rebalancing channel of quantitative qualitative easing (QQE) conducted by the BoJ from April 2013 on the basis of the assumption of imperfect asset substitutability. The model was calibrated on the basis of the structure of the Japanese economy in April 2013. The main conclusion is that the BoJ’s asset purchase has a real effect on pushing output and inflation higher, and long-term interest rates lower. Sensitivity simulation analysis shows that, given the same size of asset purchase, the persistence of asset purchase determines the peak effect in the short run. A long-lasting asset purchase can push up inflation higher, and long-term interest rates lower for a relatively longer period, but the long-run effect on output and investment does not have much difference. The policy implication for BoJ is just to announce a long-lasting QE program and make it credible to the market.

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Drygalla, Andrej, Oliver Holtemöller y Konstantin Kiesel. "THE EFFECTS OF FISCAL POLICY IN AN ESTIMATED DSGE MODEL—THE CASE OF THE GERMAN STIMULUS PACKAGES DURING THE GREAT RECESSION". Macroeconomic Dynamics 24, n.º 6 (22 de noviembre de 2018): 1315–45. http://dx.doi.org/10.1017/s1365100518000858.

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In this paper, we analyze the effects of the stimulus packages adopted by the German government during the Great Recession. We employ a standard medium-scale dynamic stochastic general equilibrium (DSGE) model extended by non-optimizing households and a detailed fiscal sector. In particular, the dynamics of spending and revenue variables are modeled as feedback rules with respect to the cyclical components of output, hours worked and private investment. Based on the estimated rules, fiscal shocks are identified. According to the results, fiscal policy, in particular public consumption, investment, and transfers prevented a sharper and prolonged decline of German output at the beginning of the Great Recession, suggesting a timely response of fiscal policy. The overall effects, however, are small when compared to other domestic and international shocks that contributed to the economic downturn. Our overall findings are not sensitive to considering fiscal foresight.

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SHEN, JIAN QI. "ISOTROPIC NEGATIVELY-REFRACTING ATOMIC-VAPOR MEDIUM". Modern Physics Letters B 21, n.º 12 (20 de mayo de 2007): 717–28. http://dx.doi.org/10.1142/s0217984907012979.

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A new scenario to realize negative refraction with a photonic-resonant vapor material that can exhibit both electric and magnetic responses via multilevel quantum coherence is suggested. Compared with the previous method of artificial composite metamaterial, where the mechanism was considered by means of classical electromagnetic theory and the materials produced have anisotropic millimetre-scale composite structures, the present scheme suggested within the framework of quantum optics can be used to design and fabricate isotropic negatively-refracting materials with atomic-scale microscopic structure units. Such an advantage may lead to a potentially important application in the techniques of superlens and perfect imaging.

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Melesse, Wondemhunegn Ezezew. "Business cycles in Ethiopia under alternative monetary policy rules". African Journal of Economic and Management Studies 10, n.º 3 (2 de septiembre de 2019): 299–313. http://dx.doi.org/10.1108/ajems-12-2018-0395.

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Purpose The purpose of this paper is to compare business cycle fluctuations in Ethiopia under interest rate and money growth rules. Design/methodology/approach In order to achieve this objective, the author constructs a medium-scale open economy dynamic stochastic general equilibrium (DSGE) model. The model features several nominal and real distortions including habit formation in consumption, price rigidity, deviation from purchasing power parity and imperfect capital mobility. The paper also distinguishes between liquidity-constrained and Ricardian households. The model parameters are calibrated for the Ethiopian economy based on data covering the period January 2000–April 2015. Findings The main result suggests that: the model economy with money growth rule is substantially less powerful or more muted for the amplification and transmission of exogenous shocks originating from government spending programs, monetary policy, technological progress and exchange rate movements. The responses of output to fiscal policy shocks are relatively stronger under autarky which appears to confirm the findings of Ilzetzki et al. (2013) who suggest bigger multipliers in self-sufficient, closed economies. With regard to positive productivity shock, however, the model with interest rate feedback rule generates a decline in output and an increase in inflation, which are at odds with conventional empirical regularities. Research limitations/implications The major implication is that a central bank regulating some measure of monetary stocks should not expect (fear) as much expansion (contraction) in output following currency devaluation (liquidity withdrawal) as a sister central bank that relies on an interest rate feedback rule. As emphasized by Mishra et al. (2010) the necessary conditions for stronger transmission of interest-rule-based monetary policy shocks are hardly existent in emerging and developing economies targeting monetary aggregates; hence the relatively weaker responses of output and inflation in the model economy with money growth rule. Monetary policy authorities need to be cautious when using DSGE models to analyze business cycle dynamics. Quite often, DSGE models tend to mimic the proverbial “crooked house” built to every man’s advise. Whenever additional modification is made to an existing baseline model, previously established regularities break down. For instance, this paper documented negative response of output to technology shock. Such contradictions are not uncommon. For example, Furlanetto (2006) and Ramayandi (2008) have also found similarly inconsistent responses to fiscal and productivity shocks, respectively. Originality/value Using DSGE models for research and teaching purposes is not common in developing economies. To the best of the author’s knowledge, only one other Ethiopian author did apply DSGE model to study business cycle fluctuation in Ethiopia albeit under the implausible assumption of perfect capital mobility and a central bank following interest rate rule. The contribution of this paper is that it departs from these two unrealistic assumptions by allowing international risk premium as a function of the net foreign asset position of the country and by applying money growth rule which closely mimics the behavior of central banks in low-income economies such as Ethiopia.

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Ming, Li. "A Deep Learning-Based Framework for Human Resource Recommendation". Wireless Communications and Mobile Computing 2022 (22 de julio de 2022): 1–12. http://dx.doi.org/10.1155/2022/2377143.

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Recently, small- and medium-scale organizations have gained favorable responses due to the dramatic economic growth in China. This rise is due to international collaborations and social-economic growth by providing good quality and quantity services. However, when compared with other developing countries, small- and medium-scale organizations in China face many restrictions considering size and contributions. Few organizations are still facing a challenge because of the difficulties and lesser quality and also with lack of human resources. The prime objective of this study is to identify the current scenario of human resources for small- and medium-scale organizations, the factors affecting it, and the steps that can be effective in overcoming these challenges. In this study, human resource data is analyzed and managed using deep learning. The functionalities of human resources are realized by the deep learning approach, and further, business volume is reduced for enhancing the efficiency of human resources. The forecasting model is proposed and tested in human resource data by implementing a gradient descent process. Additionally, a deep neural network is implemented to enhance the accuracy of the proposed model. Experimental analysis is conducted by considering several neurons at the hidden layer, iteration count, and different types of decent gradient processes. The training accuracy and validation accuracy of the proposed model by implementing a deep neural network are observed as 95.67% and 94.53%. The experimental observations reveal the potential and significance of the proposed model.

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Liu, Qiankun, Jingang Jiang, Changwei Jing, Zhong Liu y Jiaguo Qi. "A New Water Environmental Load and Allocation Modeling Framework at the Medium–Large Basin Scale". Water 11, n.º 11 (15 de noviembre de 2019): 2398. http://dx.doi.org/10.3390/w11112398.

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Waste load allocation (WLA), as a well-known total pollutant control strategy, is designed to distribute pollution responsibilities among polluters to alleviate environmental problems, but the current policy is unfair and limited to single scale or single pollution types. In this paper, a new, alternative, multi-scale, and multi-pollution WLA modeling framework was developed, with a goal of producing optimal and fair allocation quotas at multiple scales. The new WLA modeling framework integrates multi-constrained environmental Gini coefficients (EGCs) and Delphi-analytic hierarchy process (Delphi-AHP) optimization models to achieve the stated goal. The new WLA modeling framework was applied in a case study in the Xian-jiang watershed in Zhejiang Province, China, in order to test its validity and usefulness. The results, in comparison with existing practices by the local governments, suggest that the simulated pollutant load quota at the watershed scale is much fairer than the existing policies and even has some environmental economic benefits at the pollutant source scale. As the new WLA is a process-based modeling framework, it should be possible to adopt this approach in other similar geographic areas.

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Shikhmurzaev, Yulii D. y James E. Sprittles. "Wetting front dynamics in an isotropic porous medium". Journal of Fluid Mechanics 694 (2 de febrero de 2012): 399–407. http://dx.doi.org/10.1017/jfm.2012.16.

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AbstractA new approach to the modelling of wetting fronts in porous media on the Darcy scale is developed, based on considering the types (modes) of motion the menisci go through on the pore scale. This approach is illustrated using a simple model case of imbibition of a viscous incompressible liquid into an isotropic porous matrix with two modes of motion for the menisci, the wetting mode and the threshold mode. The latter makes it necessary to introduce an essentially new technique of conjugate problems that allows one to link threshold phenomena on the pore scale with the motion on the Darcy scale. The developed approach (a) makes room for incorporating the actual physics of wetting on the pore scale, (b) brings in the physics associated with pore-scale thresholds, which determine when sections of the wetting front will be brought to a halt (pinned), and, importantly, (c) provides a regular framework for constructing models of increasing complexity.

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34

Alam, Intakhab, Nadeem Sarwar y Iram Noreen. "Statistical analysis of software development models by six-pointed star framework". PLOS ONE 17, n.º 4 (1 de abril de 2022): e0264420. http://dx.doi.org/10.1371/journal.pone.0264420.

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Software Development Process Model (SDPM) develops software according to the needs of the client within the defined budget and time. There are many software development models such as waterfall, Iterative, Rapid Application Development (RAD), Spiral, Agile, Z, and AZ model. Each development model follows a series of steps to develop a product. Each model has its strengths and weaknesses. In this study, we have investigated different software development process models using the six-pointed star framework. Six-point star is a framework of project management industry standards maintained by Project Management Body of Knowledge (PMBOK). A survey is designed to evaluate the performance of well-known software process models in the context of factors defined by the six-point star framework. The survey is conducted with experienced users of the software industry. The statistical analysis and comparison of results obtained by the survey are further used to examine the effectiveness of each model for the development of high-quality software concerning lightweight and heavyweight methodologies for small, medium and large scale projects. After exploring the results of all factors of the six-pointed star model, we conclude that lightweight methodology easily handles small-scale projects. The heavyweight methodology is suitable for medium and large-scale projects, whereas the AZ model, which is one of the latest models, works efficiently with both small-scale and large-scale categories of projects.

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Oladokun, V. O. y F. T. Olagunju. "A Framework for the Development of a Manufacturing Resources Planning System". International Journal of Engineering Research in Africa 13 (diciembre de 2014): 49–59. http://dx.doi.org/10.4028/www.scientific.net/jera.13.49.

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Many Small and medium scale enterprises (SMEs), because of the limited scope and size of their operations consider investment in proprietary Enterprise Systems unattractive. Meanwhile In-house development approach has been identified as a way deepening the adoption of these productivity enhancement systems among SMEs in developing economies. This paper presents a framework for developing Manufacturing Resources Planning software adaptable for SMEs in Nigeria and other developing economies. After the critical study and analysis of manufacturing systems, algorithms were developed for generating the material requirement plans for four different lot-sizing techniques. Subsystems for determining Labour and machine capacity requirements and costs, subsystems for material and running costs were integrated into the MRP algorithms. User friendly software of the resulting system was developed using visual basic. The system components were tested using a small-scale process and a middle-scale process to ensure proper functionality. The software which comes with various graphical reporting tools like tables and bar charts was shown to be flexible and accurate, suitable for small and medium enterprises.Keyword: Enterprise Systems, inventory, Material Requirement Planning, Resources planning

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Tsvetkov, Pavel. "A theoretical framework for economic assessment of small-scale LNG projects". E3S Web of Conferences 266 (2021): 06010. http://dx.doi.org/10.1051/e3sconf/202126606010.

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The production of small-scale liquefied natural gas (SLNG) is a promising area of the gas industry, which allows to solve the problem of energy carriers distribution between end users. This differs SLNG from medium- and large-scale projects that concentrate LNG in hubs. The implementation of SLNG projects assumes the creation of an extensive network that allows covering vast territories that are not covered by centralized gas supply networks, rather than the development of single production capacities. In this paper, we propose a theoretical framework that allows to assess the attractiveness of SLNG networks development not only in terms of direct, but also indirect effects, which differ depending on the composition of project stakeholders, as well as on the stage of technological chain. The essence of term “flexibility” in relation to LNG projects has also been clarified.

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Modi, Prateek y A. M. Rawani. "An Empirical Investigation of Innovative Management Practices of Small and Medium Scale Enterprises (SMEs)". International Journal of E-Entrepreneurship and Innovation 11, n.º 1 (enero de 2021): 17–35. http://dx.doi.org/10.4018/ijeei.2021010102.

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Innovation is considered an essential activity for small and medium-scale enterprises (SMEs). The contribution of innovation in the Indian economy is very noticeable. India is continuously improving and has jumped to the 52nd position in the overall world ranking in 2019. The objectives of this study are to identify the factors of innovative management practices indulged in SMEs to achieve innovation and to propose a framework for measuring firm performance in the region of Chhattisgarh state in India. Data was gathered using a self-monitored questionnaire survey and an exploratory factor analysis (EFA) method using SPSS 20.0 software was applied to get the factors of innovative management practices. This study identified eight factors of innovative management practices involved in SMEs. Further, their reliability test and mean value analysis has been done. A conceptual framework of firm performance measurement is also presented at the end. Also, this study contributes a good amount of work in innovation management literature which will help scholars and academicians for future work.

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Aladhadh, Suliman, Shabana Habib, Muhammad Islam, Mohammed Aloraini, Mohammed Aladhadh y Hazim Saleh Al-Rawashdeh. "An Efficient Pest Detection Framework with a Medium-Scale Benchmark to Increase the Agricultural Productivity". Sensors 22, n.º 24 (12 de diciembre de 2022): 9749. http://dx.doi.org/10.3390/s22249749.

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Insect pests and crop diseases are considered the major problems for agricultural production, due to the severity and extent of their occurrence causing significant crop losses. To increase agricultural production, it is significant to protect the crop from harmful pests which is possible via soft computing techniques. The soft computing techniques are based on traditional machine and deep learning-based approaches. However, in the traditional methods, the selection of manual feature extraction mechanisms is ineffective, inefficient, and time-consuming, while deep learning techniques are computationally expensive and require a large amount of training data. In this paper, we propose an efficient pest detection method that accurately localized the pests and classify them according to their desired class label. In the proposed work, we modify the YOLOv5s model in several ways such as extending the cross stage partial network (CSP) module, improving the select kernel (SK) in the attention module, and modifying the multiscale feature extraction mechanism, which plays a significant role in the detection and classification of small and large sizes of pest in an image. To validate the model performance, we develop a medium-scale pest detection dataset that includes the five most harmful pests for agriculture products that are ants, grasshopper, palm weevils, shield bugs, and wasps. To check the model’s effectiveness, we compare the results of the proposed model with several variations of the YOLOv5 model, where the proposed model achieved the best results in the experiments. Thus, the proposed model has the potential to be applied in real-world applications and further motivate research on pest detection to increase agriculture production.

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Beraja, Martin, Erik Hurst y Juan Ospina. "The Aggregate Implications of Regional Business Cycles". Econometrica 87, n.º 6 (2019): 1789–833. http://dx.doi.org/10.3982/ecta14243.

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Making inferences about aggregate business cycles from regional variation alone is difficult because of economic channels and shocks that differ between regional and aggregate economies. However, we argue that regional business cycles contain valuable information that can help discipline models of aggregate fluctuations. We begin by documenting a strong relationship across U.S. states between local employment and wage growth during the Great Recession. This relationship is much weaker in U.S. aggregates. Then, we present a methodology that combines such regional and aggregate data in order to estimate a medium‐scale New Keynesian DSGE model. We find that aggregate demand shocks were important drivers of aggregate employment during the Great Recession, but the wage stickiness necessary for them to account for the slow employment recovery and the modest fall in aggregate wages is inconsistent with the flexibility of wages we observe across U.S. states. Finally, we show that our methodology yields different conclusions about the causes of aggregate employment and wage dynamics between 2007 and 2014 than either estimating our model with aggregate data alone or performing back‐of‐the‐envelope calculations that directly extrapolate from well‐identified regional elasticities.

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40

Odedairo, B. O. y N. Nwabuokei. "Framework for Operational Performance Measurements in Small and Medium Scale Industries Using Discrete Event Simulation Approach". Engineering, Technology & Applied Science Research 8, n.º 4 (18 de agosto de 2018): 3103–7. http://dx.doi.org/10.48084/etasr.2106.

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Globally, production systems must cope with limitations arising from variabilities and complexities due to globalization and technological advancements. To survive in spite of these challenges, critical process measures need to be closely monitored to ensure improved system performance. For production managers, the availability of accurate measurements which depict the status of production activities in real time is desired. This study is designed to develop an operational data decision support tool (ODATA-DST) using discrete event simulation approach. The work-in-process and processing time of each workstation/buffer station in a bottled water production system were investigated. The status of each job as they move through the system was used to simulate a routing matrix. The production output data for 50cl and 75cl product from 2014-2016 were collected. A mathematical model for routing jobs from the point of arrival to the point of departure was developed using discrete event simulation. A graphical user interface (GUI) was designed based on the factory’s performance measurement algorithm. Simulating the factory’s work-in-process with respect to internal benchmarks yielded a cycle time of 4.4, 6.23, 5.04 and throughput of 0.645, 0.455, 0.637 for best case scenario, worst case scenario and practical worst case scenario respectively. The factory performed below the simulated benchmark at 26%, 28%, 28% for the 50cl and at 51%, 54%, 59% for 75cl regarding the year 2014, 2015 and 2017 respectively. Performance measurement decision support tool has been developed to enhance the production manager’s decision making capability. The tool can improve production data analysis and performance predictions.

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Obioma,H, Onyeaghala,. "Servqual Model as Performance Evaluation Instrument for Small and Medium Sized Enterprises (SME): Evidence From Customers in Nigeria". European Scientific Journal, ESJ 12, n.º 28 (31 de octubre de 2016): 520. http://dx.doi.org/10.19044/esj.2016.v12n28p520.

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It is the intention of this study to ascertain if SERVQUAL model can serve as an instrument for measuring performance of small and medium scale enterprises in Nigeria. The study adopted the Kano model as the theoretical framework. Empirical works on service quality and customer satisfaction were reviewed. Survey research design was adopted and conducted with the use of structured questionnaire designed in a 5 point likert scale format ranging from strongly agree, agree, strongly disagree, disagree and undecided. Twelve (12) small and medium scale enterprises operating in six geo-political zones of Nigeria were judgmentally selected, from where a sample of 60 was drawn using Taro Yamane formula. The questionnaire was validated and its reliability established. Data presentation and analysis was carried out using tables and simple percentages. Chi-square statistic; a nonparametric technique was employed in the test of the three hypotheses formulated to guide the study. This led to rejection of the three null hypotheses indicating that: Service quality dimensions has relationship with performance of small and medium scale enterprises; tangibility, reliability, responsiveness, assurance and empathy services can be used to measure performance of small and medium scale enterprises. This justifies that SERVQUAL dimensions; tangibility, reliability, responsiveness, assurance and empathy are indicators of customer satisfaction, implying that they can be employed as performance evaluation tools for small and medium scale enterprises. It is recommended that small and medium scale enterprises should direct their operations in line with SERVQUAL dimensions, if they want to achieve customer satisfaction and business performance.

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Haider, Husnain, Rehan Sadiq y Solomon Tesfamariam. "Multilevel performance management framework for small to medium sized water utilities in Canada". Canadian Journal of Civil Engineering 42, n.º 11 (noviembre de 2015): 889–900. http://dx.doi.org/10.1139/cjce-2015-0227.

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In Canada, small to medium sized water utilities (SMWU) do not often participate in National Water and Wastewater Benchmarking Initiative due to lesser economies of scale, lack of resources, and data limitations. Consequently, such SMWU are managing their functional components (i.e., environmental, personnel, operational, physical assets, customer satisfaction, public health, and financial) without quantitatively assessing and knowing if they are meeting their performance objectives. A multilevel performance management framework, consisting of five modules has been developed and implemented for SMWU in BC, Canada. The framework provides an approach to identify and select the suitable performance indicators for SMWU, and to use them for inter-utility performance benchmarking under limited data. The subsequent modules can be used for detailed performance management at utility, system, and sub-component levels. The utility managers can effectively employ this framework to identify the underperforming functional components and can rationally take corrective actions, and address customer satisfaction with efficient inventory management and data analyses.

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43

Ina Ibor, Bassey, Amenawo Ikpa Offiong y Enyeokpon Samuel Mendie. "FINANCIAL INCLUSION AND PERFORMANCE OF MICRO, SMALL AND MEDIUM SCALE ENTERPRISES IN NIGERIA". International Journal of Research -GRANTHAALAYAH 5, n.º 3 (31 de marzo de 2017): 104–22. http://dx.doi.org/10.29121/granthaalayah.v5.i3.2017.1758.

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Financial inclusion assures easy access to financial services by enabling the disadvantaged and vulnerable sections of the society to actively contribute to development and protect themselves against socio-economic shocks. Nigeria has a sizeable rural poor population with limited access to conventional financial institutions or services. This study investigated the impact of financial inclusion on the micro, small and medium enterprises (MSMEs) performance in Nigeria. The survey research design method was used, involving the use of questionnaires, in collecting data from respondents. Data were analyzed using the Pearson Chi-square technique. The results show that, whereas financial inclusion positively and significantly impacts the operations and growth of MSMEs, distance to financial services access points and infrastructural deficiency challenged fast and effective access to financial services by MSMEs in Nigeria. The study recommends that deliberate efforts should be made to spread access points to more rural areas and improve infrastructure to promote FI. This should include a policy roadmap for expanding financial services access points to unbanked and underserved areas using the financial services geospatial map. Furthermore, the digitizing of payments across the country should be prioritized to include enhanced ICT/E-banking tools and a consumer protection framework.

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44

Pérez-Ràfols, Francesc, Fredrik Forsberg, Gunnar Hellström y Andreas Almqvist. "A Stochastic Two-Scale Model for Rarefied Gas Flow in Highly Heterogeneous Porous Media". Transport in Porous Media 135, n.º 1 (16 de septiembre de 2020): 219–42. http://dx.doi.org/10.1007/s11242-020-01476-z.

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Abstract This paper presents the development of a model enabling the analysis of rarefied gas flow through highly heterogeneous porous media. To capture the characteristics associated with the global- and the local-scale topology of the permeable phase in a typical porous medium, the heterogeneous multi-scale method, which is a flexible framework for constructing two-scale models, was employed. The rapid spatial variations associated with the local-scale topology are accounted for stochastically, by treating the permeability of different local-scale domains as a random variable. The results obtained with the present model show that an increase in the spatial variability in the heterogeneous topology of the porous medium significantly reduces the relevance of rarefaction effects. This clearly shows the necessity of considering a realistic description of the pore topology and questions the applicability of the results obtained for topologies exhibiting regular pore patterns. Although the present model is developed to study low Knudsen number flows, i.e. the slip-flow regime, the same development procedure could be readily adapted for other regimes as well.

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Amoroso, Ricardo O., Ana M. Parma, J. M. (Lobo) Orensanz y Domingo A. Gagliardini. "Zooming the macroscope: medium-resolution remote sensing as a framework for the assessment of a small-scale fishery". ICES Journal of Marine Science 68, n.º 4 (12 de noviembre de 2010): 696–706. http://dx.doi.org/10.1093/icesjms/fsq162.

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Abstract Amoroso, R. O., Parma, A. M., Orensanz, J. M., and Gagliardini, D. A. 2011. Zooming the macroscope: medium-resolution remote sensing as a framework for the assessment of a small-scale fishery. – ICES Journal of Marine Science, 68: 696–706. Management of small-scale fisheries targeting sedentary stocks requires integration of information about processes operating and observable at different spatial and temporal scales. An integrated approach was developed with a scallop (Aequipecten tehuelchus) fishery in a small, semi-enclosed Patagonian basin as a demonstration case. Medium-resolution (30 m2) satellite (Landsat) data, used to identify circulation patterns, were combined with information from fishery surveys and recruitment experiments to link oceanographic processes with population dynamics. A frontal system splits San José Gulf (northern Argentine Patagonia) into two oceanographic domains (East and West) with distinct hydrographic regimes. In the West Domain, where circulation is highly advective and governed by turbulent vorticial fluxes, larval settlement on artificial collectors was insignificant over five reproductive seasons and no important scallop grounds were ever found. In the East Domain, where the main fishing grounds are, spat abundance varied between sites and years, but was always significant. Growth rates displayed strong clinal variation within the East Domain, decreasing clockwise away from the entrance to the Gulf and reflecting inferred circulation and gradual nutrient extinction. A physical mechanism capable of dispersing larvae over long distances towards the north, into the adjacent San Matias Gulf, was identified from Landsat images. The large-scale patterns of variation in growth, distribution, and recruitment of the Tehuelche scallop stock could not have been interpreted without an integrative approach to data assemblage and analysis, including satellite remote sensing.

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46

Cheng, Zhixin, Xiao Hua Wang, Isabel Jalón-Rojas y Yue Liu. "Reconstruction of sedimentation changes under anthropogenic influence in a medium-scale estuary based on a decadal chronological framework". Estuarine, Coastal and Shelf Science 227 (octubre de 2019): 106295. http://dx.doi.org/10.1016/j.ecss.2019.106295.

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Di Nucci, Carmine y Daniele Celli. "From Darcy Equation to Darcy Paradox". Fluids 7, n.º 4 (22 de marzo de 2022): 120. http://dx.doi.org/10.3390/fluids7040120.

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This theoretical paper focuses on the single-phase fluid flow through a granular porous medium. The emphasis is on the Darcy flow regime (without free boundary) of a linear viscous fluid in a saturated, deformable, homogeneous porous medium. The approach is developed at the Darcy scale (also referred to as macroscale or phenomenological scale). Within this framework, some discrete aspects of the flow model are highlighted, the governing equations are revisited, the thermodynamic state functions are reconsidered, and the Darcy paradox is presented. The Darcy paradox is illustrated for the isoshoric-isothermal flow of a viscous fluid in the liquid state, in a homogenous porous medium. After some remarks about the intrinsic assumption of this kind of flow, the governing equations are reduced to a well-known parabolic equation. According to this equation, infinitesimal pressure disturbances diffuse at an infinite speed. To remove this paradox, a mathematical model, based on the elementary scales method, is employed.

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48

Stewart, Timothy, Sally Rehorick y Billy Perry. "Adapting the Canadian Language Benchmarks for Language Assessment". TESL Canada Journal 18, n.º 2 (30 de junio de 2001): 48. http://dx.doi.org/10.18806/tesl.v18i2.910.

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The purpose of this article is to describe the development of an instrument for assessing the writing development of students in an English-medium university in Japan. We begin with a description of the setting of the college and the unique nature of its program. Next we discuss the process of selecting a language proficiency framework suitable for the four years of the degree. The Canadian Language Benchmarks (Citizenship and Immigration Canada, 1996) were chosen and subsequently formed the basis for the development of the rating scale. The process of developing the scale held a number of challenges, given the target population and the requirement to have an instrument usable by both language development specialists and nonspecialists. Issues such as the institutional context, the framework for evaluating language development, and development and refinement of the assessment scale over the first two years of the project are discussed.

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49

Tóth, Boglárka y István Ihász. "Validation of subgrid scale ensemble precipitation forecasts based on the ECMWF’s ecPoint Rainfall project". Időjárás 125, n.º 3 (2021): 397–418. http://dx.doi.org/10.28974/idojaras.2021.3.2.

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Nowadays, state-of-the-art numerical weather prediction models successfully predict the general weather characteristics several days ahead, but forecasting extreme precipitation is quite challenging even in the short time range. In the framework of the ecPoint Project, the European Centre for Medium-Range Weather Forecasts (ECMWF) developed a new innovative probabilistic post-processing tool which produces 4-day precipitation forecast as accurate as the raw ensemble forecast at day 1. In the framework of the scientific co-operation between ECMWF and the Hungarian Meteorological Service (OMSZ), we were invited to participate in the validation of the experimental products. Quasi operational post-processed products have been available since July 1, 2018. During our work, besides using different verification technics, a new ensemble meteogram was also developed which can support operational forecasters during extreme precipitation events. As a result of our work, products of the ecPoint Project have been included in the operational forecasting activity.

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50

Falgarone, Edith, Benjamin Godard y Pierre Hily-Blant. "Turbulence in the Diffuse Interstellar Medium". Proceedings of the International Astronomical Union 7, S280 (junio de 2011): 187–202. http://dx.doi.org/10.1017/s1743921311024975.

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AbstractThe diffuse interstellar medium (ISM) hosts the first steps of interstellar chemistry and the seeds of dense structures. Since its turbulent pressure by far exceeds its thermal pressure, turbulence must play a prominent role in its evolution. Fed at galactic scales, turbulent energy cascades down to the dissipation scales, but as in both laboratory and atmospheric turbulence, it does so in an intermittent way : only a tiny fraction of the small-scales is fed by the turbulent cascade, so that dissipation occurs in bursts. In diffuse molecular clouds, where they can be observed, the signatures of intermittency are: (1) the non-Gaussian statistics of velocity increments, and (2) the existence of coherent structures of intense velocity-shear that appear to channel the large-scale turbulent energy down to milliparsec scales. Attempts at modelling the warm chemistry triggered in the diffuse ISM by bursts of turbulent dissipation are promising : in this framework, the so far unexplained molecular richness observed in this medium is naturally understood, in particular its CH+, HCO+ and CO abundances. Turbulent dissipation is also likely at the origin of the H2 rotational line emission of the diffuse ISM and of a significant fraction of its [C II] emission.

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