The question of optimal portfolio is addressed. The conventional Markowitz portfolio optimisation is discussed and the shortcomings due to non-Gaussian security returns are outlined. A method is proposed to minimise the likelihood of extreme non-Gaussian drawdowns of the portfolio value. The theory is called leptokurtic, because it minimises the effects from ”fat tails” of returns. The leptokur...

Aquifer information carried by aquifer test data may be affected by the presence of a finite thickness skin around the wellbore. The mathematical treatment for an aquifer accounting for the skin zone can be characterized by five parameters, that is, the outer radius of the skin zone and the transmissivity and storativity for each of the skin and aquifer zones. Sensitivity analysis was performed...

The present study examined the effect of the geometric parameters of the Rockfill dams on the 2D static analysis of slope stability. In this regard, several numerical models analyzed for eight heights, three slopes of upstream and downstream, three vertical and skewed core thicknesses and four different impounding time stages namely, "End of Construction", "Full Reservoir", "Half Full Reservoir...

We study the class of Azéma–Yor processes defined from a general semimartingale with a continuous running supremum process. We show that they arise as unique strong solutions of the Bachelier stochastic differential equation which we prove is equivalent to the Drawdown equation. Solutions of the latter have the drawdown property: they always stay above a given function of their past supremum. W...

This work can be considered as an effort to recognize the relationships between the drawdown and recovery data for the aquifer system, and instead of separated two graphs including Cooper – Jacob for the pumping test and Theis recovery straight line methods, Elhag (2014) innovational simplified solution agrees with more complicated solutions, and useful for determine aquifer parameter values in...

[1] Transient hydraulic tomography (THT) is a potentially cost-effective and highresolution technique for mapping spatial distributions of the hydraulic conductivity and specific storage in aquifers. Interpretation of abundant well hydrographs of a THT survey, however, is a computational challenge. We take on this challenge by developing an estimation approach that utilizes the zeroth and first...

This study uncovers the impact of COVID-19 on Islamic equity markets compared to their conventional counterparts. The extremely large-scale drawdown across signifies an indiscriminate impact. To some extent, Asian show relative resilience Both and non-Islamic signpost a quicker recovery than rest regions, Middle East & Africa, Europe, America. It appears that higher return leads smaller maximum...

Motivated by evaluating the limiting distribution of randomly biased random walks on trees, we compute the exact value of a negative moment of the maximal drawdown of the standard Brownian meander.

Ice surface altimetry from ICESat-1 and NASA aircraft altimeter overflights spanning 2002– 09 indicate that a region of lower Crane Glacier, Antarctic Peninsula, shows an unusual temporal pattern of elevation loss: a period of very rapid drawdown ( 91ma between September 2004 and September 2005) bounded by periods of large but more moderate rates (23ma until September 2004; 12ma after September...

Proposed withdrawal of groundwater from the surficial aquifer system confined zone, or the upper and lower Brunswick aquifers in eastern Camden County, Georgia, could result in drawdown extending beneath the Cumberland Sound and potentially could affect groundwater levels and natural resources at Cumberland Island National Seashore. Using a nonequilibrium formula, estimated drawdown after 5 yea...