A Mathematical Model and Programme Support for Determination of the Values of the Marginal Reserve Requirement as Instrument of Monetary Policy

This paper studies the problem of interdependence between central bank and commercial bank goals. The basic central bank task is to achieve and to maintain price stability. Croatian external debt has been increasing for years and so the activities of the Croatian National Bank are designed to correct this situation. In order to stop the further increase of the external debt, the Croatian National Bank uses several monetary policy instruments, among which is the marginal reserve requirement. On the other hand, the goal of commercial banks is to maximise profits. Banks take loans from abroad at a lower interest rate and invest this money in Croatia at a higher interest rate, thus fulfilling their goal. In order to obtain the desired effects of the marginal reserve requirement, its optimal percentage value should be determined. This problem is modelled as a bi-level mixed 0-1 programming problem. The objective of the leader (Croatian National Bank) is to minimize the increase in household loans by setting different percentages of the reserve requirements for loans extended to households and for those granted to enterprises. The objective of the followers (banks) is to maximize profits. In order to solve this NP-hard problem a heuristic is proposed. In order to verify the model, the paper ends with simulations and the presentation of computational results.monetary policy instruments, commercial banks credit activity, marginal reserve requirement, bi-level mixed 0-1 programming problem, NP-hard problem, heuristic

Dual-polarized, broadband metasurface cloaks for antenna applications

A communication system that reduces the mutual influence of antennas operating in similar or different frequency bands. The communication system includes a first and a second antenna operating in a first and a second frequency band, respectively, and placed in close proximity to each other. The first antenna is covered by a conformal mantle metasurface with anti-phase scattering properties thereby cancelling the scattering in the second frequency band. The conformal mantle metasurface consists of a patterned metallic sheet comprising slits both in an azimuthal and a vertical direction to reduce both vertical and horizontal polarization scattering. When the first antenna is a low-band dipole antenna and when the second antenna is a high-band dipole antenna, the conformal mantle metasurface reduces the low-band blockage without disrupting the performance of both antennas in terms of radiation pattern and impedance matching.Board of Regents, University of Texas Syste

Employment uncertainty a year after the irruption of the covid-19 pandemic

This paper examines the evolution of consumer uncertainty about unemployment one year after the irruption of the covid-19 pandemic in European countries. Since uncertainty is not directly observable, we use two alternative methods to directly approximate it. Both approaches are based on qualitative expectations elicited form the consumer survey conducted by the European Commission. On the one hand, following Dibiasi and Iselin (2019), we use the share of consumers unable to formalize expectations about unemployment (Knightian-type uncertainty). On the other hand, we use the geometric discrepancy indicator proposed by Claveria et al. (2019) to quantify the proportion of disagreement in business and consumer expectations. We have used information from 22 European countries. We find that both uncertainty measures covary. Although we observe marked differences across countries, in most cases the perception of employment uncertainty peaked before the outbreak of the crisis, plummeted during the first months of the lockdown, and started rising again since the past few months. When testing for cointegration with the unemployment rate, we find that the discrepancy indicator exhibits a long- term relationship with unemployment in most countries, while the Knightian uncertainty indicator shows a purely short-run relationship. The impact of both indicators on unemployment is characterised by considerable asymmetries, showing a more intense reaction to decreases in the level of uncertainty. While this finding may seem counterintuitive at first sight, it somehow reflects the fact that during recessive periods, the level of disagreement in the employment expectations of consumers drops considerably

Atomistic submodel implementation and application within microstructure analysis by molecular dynamics

Classical continuum mechanics faces substantial difficulties for adequately describe stress and strain distributions around microstructural material discontinuities such as crystallographic defects, voids, and grain boundaries. One way to improve the microstructural model is the development of the atomistic submodel that provides a minimal increase in the amount of atomistic data, but provides more accurate stress predictions without time consuming calculation of full atomistic model. In the proposed approach continuum model, discretized by finite elements, provides a displacement field for atoms on the edge of the simulation cell of the the atomistic submodel driven by molecular dynamics. The final result is the utilization of the best from both worlds, calculation speed of the constinuum mechanics using finite elements method and informing it with relevant material properties inferred from atomistic simulations by using molecular dynamics where it is the necessary

Application of mixed meshless solution procedures for deformation modeling in gradient elasticity

The present study is related to the utilization of the mixed Meshless Local PetrovGalerkin (MLPG) methods for solving problems in gradient elasticity, which are governed by fourth-order differential equations. Here, three different numerical MLPG methods are presented, where the continuity requirements for the approximation functions are lowered by applying different mixed procedures to improve the numerical accuracy and efficiency. The first one is based on the direct solution of the problem, where the primary variable (displacement) and its independently chosen higher-order variables are approximated separately. The global discretized system of equations consists of appropriate equilibrium and compatibility equations written for each node and the solution vector contains all unknown independent nodal variables. Such approach demands only the first-order continuity of meshless approximation functions. The second and third procedures are both based on the displacement-based operator-split approach, where the original gradient elasticity problem is solved as two uncoupled problems governed by the second-order differential equations. Herein, in both uncoupled problems only primary variable (displacement) and its first derivative (strain) are approximated independently. In these procedures the original problem is solved by a staggered approach, where the solution of the first uncoupled equation is utilized as an input in the second equation. The main difference in the second and third procedure is that the one is based on the solution of the local weak forms of the governing equations, while the other is based on solution of the strong forms of the same equations. The accuracy of the presented computational methods is compared to analytical solutions and demonstrated on a one-dimensional benchmark problem of axial bar in gradient elasticity

The Analysis of Local Subsoil Failure

The paper deals with a case history of a local foundation failure caused by removing the neighbouring building. Displacement measurements after removing the neighbouring all the working stages at the site. The shape of the deformation curve points to failure after removing the neighbouring old building. The foundation soil is a Moscow sand typical for the large part of the urban Moscow area. It is a poorly graded fine sand of a medium density. Using back analysis for all working stages the peak and residual parameters caused by foundation failure were defined. The ratio of residual to peak value of 0 for a foundation sand corresponds very well to literature sources referring to this type of soil. Numerical model proved that the Fs value was satisfactory after the completion of protection works. On the other hand, measured displacement values showed that the displacement gradient mainly dropped to the negligible value

Evolutionary particulars of COVID-19 in elderly patients

Scientific Laboratory of Gerontology, Geriatrics and Occupational Medicine, Nicolae Testemitanu State University of Medicine and Pharmacy, Chisinau, the Republic of Moldova. The 75th anniversary of Nicolae Testemitanu State University of Medicine and Pharmacy of the Republic of Moldova (1945-2020)Background: The new SARS-CoV-2 coronavirus affects a large number of people worldwide, and the elderly are particularly affected because of their vulnerability. Thus, the elderly patients and those with comorbidities have an increased risk of developing a severe disease and show an increased mortality rate. Although they may show mild symptoms of illness and low-grade fever in the early days, they may worsen clinically rapidly, requiring ongoing monitoring. Material and methods: The prospective study was performed on a group of 96 patients (mean age 61.41 ± 3.42 years), with a predominance of men, hospitalized in the Holy Trinity Hospital of Chisinau who met the clinical case definition and were laboratory case-confirmed with COVID-19. Patients were clinically and paraclinically investigated according to the WHO Provisional National Clinical Protocol for COVID-19 infection reporting. The data were statistically processed by the Statistics 10 program. Results: Of the 96 patients with COVID-19, 85 (88.54%) reported at least one had a comorbidity. The prevalence of comorbidities was the following: chronic coronary syndromes (40.1%), hypertension (39.7%), diabetes (16.04%), chronic obstructive pulmonary disease (17.3%), malignancy (13.04%), cerebrovascular disease (10.6%), chronic kidney disease (4.3%) and viral hepatitis B (1.8%). Severe cases of the disease were revealed – 58, medium severity – 38 cases. All critical cases resulting in death (7.29%) showed comorbidities with respiratory symptoms, as well as with the onset of acute respiratory failure. Conclusions: The elderly, male gender and the presence of comorbidities in patients with COVID-19 determine the severe course of the disease and an increased mortality rate

Social factors of fragility in elderly people

Department of Internal Medicine, Geriatrics and Occupational Medicine, Gerontology Laboratory, "Nicolae Testemitanu" State University of Medicine and Pharmacy, Chisinau, Republic of MoldovaIntroduction Fragility is a clinical condition, associated with the pathological aging process, and represents a major risk in the occurrence of chronic non-communicable diseases and is closely related to functional disability and comorbidities, with the coexistence of these in 21.5% of the elderly. In case of people over 65, fragility is caused by many factors, some of which are social, which affect the quality and length of life that contributes to disability and polypathology. In societies where is a high unemployment rate, there are no opportunities to use the workforce of those elderly people who maintain their physical and mental potential at an acceptable level and can occasionally perform various activities. Also, the third age is characterized by a drastic restriction of social and professional roles, as well as by a massive presence of degenerative diseases, which reduce the mobility of the individual and increase the risk of his dependence on family and society. A frequent sign of old age is the loneliness, both physically and psychologically. Another widespread social phenomenon in contemporary society is violence, in front of which older people become one of the most vulnerable categories of the population. Purpose Evaluation of the widespread social factors in fragility syndrome of elderly patients in the geriatric ward. Material and methods The retrospective study included 410 electronic files (https://www.ams.md/siaams_scms/) in 2018 of patients aged over 65 years, the average being 71.11 ± 0.29 years. The female sex constituted 60%, and the male 40% of cases, hospitalized in the geriatric ward. The social factors of fragility included the loneliness of the elderly, employment, violence, isolation and income. The variables were expressed as number or percentage and arithmetic mean. Results The results of the evaluation of the social situation of the elderly in the study revealed the fragility syndrome - 28.29% of cases; the share of loneliness of the elderly of 34.14% of cases, the elderly living with one of the spouses - 49.75% of cases, with one of the parents - 1.46% and with the children's family - 17.80% of elderly patients. At the same time, the share of family isolated elderly people was established - 8.78% of cases and socially isolated elderly people - 7.07% of cases. In this study was established a percentage of the elderly who are subjected to violence, thus, domestic violence reported 2.19% of the elderly, physical violence - 0.73% of cases, moral violence - 3.17% of cases and violence outside the family - 4.14% of cases. The situation in relation to the elderly employed in the field of work was determined a percentage of 6.58% of elderly people over 65 years of age, employed in the field of work. At the same time, the monthly incomes of the elderly were evaluated, thus, the patients declared an average income of 1579.451 ± 38.04 lei. Beneficiaries of social service was 4.46% of elderly patients. Conclusions Aging causes a change in social lifestyle. The most common social factors are non-beneficiaries of social services (95.54%), unemployment (93.42%), loneliness (34.14%), violence (10.23%), which significantly alter the quality of life, which has important consequences in terms of social protection and health care for the elderly and increases the need for social services

An application of deep learning for exchange rate forecasting

This paper examines the performance of several state-of-the-art deep learning techniques for exchange rate forecasting (deep feedforward network, convolutional network and a long short-term memory). On the one hand, the configuration of the different architectures is clearly detailed, as well as the tuning of the parameters and the regularisation techniques used to avoid overfitting. On the other hand, we design an out-of-sample forecasting experiment and evaluate the accuracy of three different deep neural networks to predict the US/UK foreign exchange rate in the days after the Brexit took effect. Of the three configurations, we obtain the best results with the deep feedforward architecture. When comparing the deep learning networks to time-series models used as a benchmark, the obtained results are highly dependent on the specific topology used in each case. Thus, although the three architectures generate more accurate predictions than the time-series models, the results vary considerably depending on the specific topology. These results hint at the potential of deep learning techniques, but they also highlight the importance of properly configuring, implementing and selecting the different topologies