This study examines the optimal allocation of funds between national and urban parks.Since travel costs to national parks are significantly higher than to urban parks, poor households tend to visit the latter more Accessories frequently, whereas rich households favor the former.Therefore, allocating public funds to improving the quality of national

Abstract To investigate the influences of heterogeneity and waning immunity on measles transmission, we formulate a network model with periodic transmission rate, and theoretically examine the threshold dynamics.We numerically find that the waning of immunity can lead to an increase in the basic reproduction number R 0 $R_{0}$ and the density of in

Abstract This article discusses the uncertainty of risk-sharing rules in local financial governance.That Sheetmetal Drill Set is, when the formal risk-sharing rules of financial transactions are agreed upon in advance, actual operations are uncertain.First, the institutional contradiction at the macro-level is an important structural source of the