Numerous economic time series do not have a constant mean and in practical situations, we often see that the variance of observational error is subject to a substantial variability over time. This phenomenon is known ...Numerous economic time series do not have a constant mean and in practical situations, we often see that the variance of observational error is subject to a substantial variability over time. This phenomenon is known as volatility. To take into account the presence of volatility in an economic series, it is necessary to resort to models known as conditional heteroscedastic models. In these models, the variance of a series at a given time point depends on past information and other data available up to that time point, so that a conditional variance must be defined, which is not constant and does not coincides with the overall variance of the observed series. There is a very large variety of nonlinear models in the literature, which are useful for the analysis of any economic time series with volatility, but we will focus in analyzing our series of interest using ARCH type models introduced by Engle （1982） and their extensions. These models are non-linear in terms of variance. Our objective will be the study of the monthly inflation data of Argentina for the period from January 1943 to December 2013. The data is officially published by the National Institute of Statistics and Censuses （or INDEC as it is known in Argentina）. Although it is a very long period in which various changes and interventions took place, it can be seen that certain general patterns of behavior have persisted over time, which allows us to admit that the study can be appropriately based on available information.展开更多
A computational framework for parachute inflation is developed based on the immersed boundary/finite element approach within the open-source IBAMR library.The fluid motion is solved by Peskin's diffuse-interface i...A computational framework for parachute inflation is developed based on the immersed boundary/finite element approach within the open-source IBAMR library.The fluid motion is solved by Peskin's diffuse-interface immersed boundary(IB)method,which is attractive for simulating moving-boundary flows with large deformations.The adaptive mesh refinement technique is employed to reduce the computational cost while retain the desired resolution.The dynamic response of the parachute is solved with the finite element approach.The canopy and cables of the parachute system are modeled with the hyperelastic material.A tether force is introduced to impose rigidity constraints for the parachute system.The accuracy and reliability of the present framework is validated by simulating inflation of a constrained square plate.Application of the present framework on several canonical cases further demonstrates its versatility for simulation of parachute inflation.展开更多
Inflationary spectral index from the Langevin equation is calculated under the frame of warm inflationary scenario with inflaton interacting with U(1) gauge fields through the Chern–Simons coupling ∝ФF_(μv)F^(μv)...Inflationary spectral index from the Langevin equation is calculated under the frame of warm inflationary scenario with inflaton interacting with U(1) gauge fields through the Chern–Simons coupling ∝ФF_(μv)F^(μv). Under the strong dissipative condition, the spectral index is calculated in terms of the ratio of Hubble parameter to temperature H/T. Then relation between H/T and other cosmic parameters is analytically expressed, based on which a spectral index related to the Chern–Simons coupling strength is further obtained. Numerical results show that cosmic temperature T closes to a constant during inflation and decreases after inflation without a reheating process. Meanwhile, the ratio H/T tends to a constant if the gauged coupling constant is less than a threshold. This phenomenon shows that cosmic temperature may be an important physical parameter with a special value and adiabatic approximation still holds. We obtain the estimate H/T ≤ 0.3377 during inflation from Planck data and other constraint conditions.展开更多
On August 16<sup>th</sup>, 2022, Public Law 117-169, The Inflation Reduction Act of 2022, was signed into law by the President of the United States, Joseph R. Biden Jr. The Inflation Reduction Act of 2022 ...On August 16<sup>th</sup>, 2022, Public Law 117-169, The Inflation Reduction Act of 2022, was signed into law by the President of the United States, Joseph R. Biden Jr. The Inflation Reduction Act of 2022 provides the Native Hawaiian community an opportunity to engage in activities of climate resilience and adaptation through making funds available to support such actions. This article provides a preliminary policy analysis of the Inflation Reduction Act of 2022 to identify the opportunities presented by this legislation that can provide ecological and cultural benefit to the Native Hawaiian community. Findings suggest policy language included in this Act is broad which emphasizes the need for the Senior Program Director of the Office of Native Hawaiian Relations, who is tasked with fund distribution, to rely upon the knowledge of the Native Hawaiian community and ecological experts to direct funds in a manner that best benefits the Native Hawaiian community.展开更多
We extend the Standard Model with a scalar warm dark matter field S with an interaction with the Higgs boson ∅. This warm dark matter scenario is in agreement with cosmological observations if S and ∅ come into t...We extend the Standard Model with a scalar warm dark matter field S with an interaction with the Higgs boson ∅. This warm dark matter scenario is in agreement with cosmological observations if S and ∅ come into thermal and diffusive equilibrium before the temperature drops below the Higgs boson mass m<sub>H</sub>. We study inflation driven by the fields ∅ or S, and also study preheating and reheating, in order to constrain the parameters of this extension of the Standard Model. It is remarkable that, with the current data, these models pass a closure test with no free parameters.展开更多
This paper empirically examined the impact of fiscal policy on inflation in Nigeria.Time series data on inflation,government revenue,government expenditure,and gross domestic product were sourced from the Central Bank...This paper empirically examined the impact of fiscal policy on inflation in Nigeria.Time series data on inflation,government revenue,government expenditure,and gross domestic product were sourced from the Central Bank of Nigeria(CBN).The aforementioned secondary data cover the period from 1981 to 2021.The Augmented Dickey Fuller(ADF)unit root test and Johansen co-integration test were used to testing for data stationarity and the existence or otherwise of co-integrating equations respectively.Thereafter,data were analyzed using Ordinary Least Square and Parsimonious Error Correction techniques.Findings from the study show that government expenditure and revenue both have a positive relationship with the rate of inflation,though the latter is not statistically significant.Also,there is a positive but insignificant relationship between inflation and gross domestic product.In line with the above findings,we,therefore,recommend that the Nigerian government at all levels(local,state,and federal)should be tactful in the use of fiscal policy tools to avoid triggering inflationary pressure and its negative multiplier effects on the welfare of its citizenry.展开更多
文摘Numerous economic time series do not have a constant mean and in practical situations, we often see that the variance of observational error is subject to a substantial variability over time. This phenomenon is known as volatility. To take into account the presence of volatility in an economic series, it is necessary to resort to models known as conditional heteroscedastic models. In these models, the variance of a series at a given time point depends on past information and other data available up to that time point, so that a conditional variance must be defined, which is not constant and does not coincides with the overall variance of the observed series. There is a very large variety of nonlinear models in the literature, which are useful for the analysis of any economic time series with volatility, but we will focus in analyzing our series of interest using ARCH type models introduced by Engle （1982） and their extensions. These models are non-linear in terms of variance. Our objective will be the study of the monthly inflation data of Argentina for the period from January 1943 to December 2013. The data is officially published by the National Institute of Statistics and Censuses （or INDEC as it is known in Argentina）. Although it is a very long period in which various changes and interventions took place, it can be seen that certain general patterns of behavior have persisted over time, which allows us to admit that the study can be appropriately based on available information.
基金supported by the Open Project of Key Laboratory of Aerospace EDLA,CASC(No.EDL19092208)。
文摘A computational framework for parachute inflation is developed based on the immersed boundary/finite element approach within the open-source IBAMR library.The fluid motion is solved by Peskin's diffuse-interface immersed boundary(IB)method,which is attractive for simulating moving-boundary flows with large deformations.The adaptive mesh refinement technique is employed to reduce the computational cost while retain the desired resolution.The dynamic response of the parachute is solved with the finite element approach.The canopy and cables of the parachute system are modeled with the hyperelastic material.A tether force is introduced to impose rigidity constraints for the parachute system.The accuracy and reliability of the present framework is validated by simulating inflation of a constrained square plate.Application of the present framework on several canonical cases further demonstrates its versatility for simulation of parachute inflation.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11864030 and 62061037)Inner Mongolia Natural Science Foundation (Grant Nos. 2021LHBS01001 and 2020BS02011)the Scientific Research Funding Project for Introduced High Level Talents of IMNU (Grant No. 2020YJRC001)。
文摘Inflationary spectral index from the Langevin equation is calculated under the frame of warm inflationary scenario with inflaton interacting with U(1) gauge fields through the Chern–Simons coupling ∝ФF_(μv)F^(μv). Under the strong dissipative condition, the spectral index is calculated in terms of the ratio of Hubble parameter to temperature H/T. Then relation between H/T and other cosmic parameters is analytically expressed, based on which a spectral index related to the Chern–Simons coupling strength is further obtained. Numerical results show that cosmic temperature T closes to a constant during inflation and decreases after inflation without a reheating process. Meanwhile, the ratio H/T tends to a constant if the gauged coupling constant is less than a threshold. This phenomenon shows that cosmic temperature may be an important physical parameter with a special value and adiabatic approximation still holds. We obtain the estimate H/T ≤ 0.3377 during inflation from Planck data and other constraint conditions.
文摘On August 16<sup>th</sup>, 2022, Public Law 117-169, The Inflation Reduction Act of 2022, was signed into law by the President of the United States, Joseph R. Biden Jr. The Inflation Reduction Act of 2022 provides the Native Hawaiian community an opportunity to engage in activities of climate resilience and adaptation through making funds available to support such actions. This article provides a preliminary policy analysis of the Inflation Reduction Act of 2022 to identify the opportunities presented by this legislation that can provide ecological and cultural benefit to the Native Hawaiian community. Findings suggest policy language included in this Act is broad which emphasizes the need for the Senior Program Director of the Office of Native Hawaiian Relations, who is tasked with fund distribution, to rely upon the knowledge of the Native Hawaiian community and ecological experts to direct funds in a manner that best benefits the Native Hawaiian community.
文摘We extend the Standard Model with a scalar warm dark matter field S with an interaction with the Higgs boson ∅. This warm dark matter scenario is in agreement with cosmological observations if S and ∅ come into thermal and diffusive equilibrium before the temperature drops below the Higgs boson mass m<sub>H</sub>. We study inflation driven by the fields ∅ or S, and also study preheating and reheating, in order to constrain the parameters of this extension of the Standard Model. It is remarkable that, with the current data, these models pass a closure test with no free parameters.
文摘This paper empirically examined the impact of fiscal policy on inflation in Nigeria.Time series data on inflation,government revenue,government expenditure,and gross domestic product were sourced from the Central Bank of Nigeria(CBN).The aforementioned secondary data cover the period from 1981 to 2021.The Augmented Dickey Fuller(ADF)unit root test and Johansen co-integration test were used to testing for data stationarity and the existence or otherwise of co-integrating equations respectively.Thereafter,data were analyzed using Ordinary Least Square and Parsimonious Error Correction techniques.Findings from the study show that government expenditure and revenue both have a positive relationship with the rate of inflation,though the latter is not statistically significant.Also,there is a positive but insignificant relationship between inflation and gross domestic product.In line with the above findings,we,therefore,recommend that the Nigerian government at all levels(local,state,and federal)should be tactful in the use of fiscal policy tools to avoid triggering inflationary pressure and its negative multiplier effects on the welfare of its citizenry.
