Transport studies of Kondo behavior,ferromagnetic and antiferromagnetic order in U1−xThxSb

We report electrical resistivity, Hall effect and magnetization measurements in the system U_1?xTh_xSb for magnetic fields up to 100 kOe. In U_0.14Th_0.86Sb a Kondo-like behavior of the resistivity is detected and the interaction J_df between the conduction d electrons and the uranium f electrons is found to be about ?0.2 eV. The dilution of USb by ThSb leads to large modifications of the electrical transport properties, reflecting the change from antiferromagnetism to ferromagnetism and simultaneously a decrease of the ordered magnetic moment per uranium atom occurs. A simple model is presented which accounts for this decrease assuming that all the conduction electrons added by thorium are polarized antiparallel to the remaining uranium f electrons due to the negative J_df. The Kondo temperature is used to estimate the band width and the binding energy of the 5f state.     

An Integer Goal Programming Model for Determining Military Aircraft Expenditures

The decision-making process involved in the procurement of military weapon systems, although quite critical and complex, still encompasses the basic characteristics of a capital budgeting problem. Given a number of expenditure items and a limited budget, it is desired to procure those weapon systems that will achieve the goals and objectives of the government and/or military in the most efficient manner. Since these objectives are typically numerous and diverse, traditional decision-making techniques are not applicable. As such, integer goal programming is suggested as a technique to be employed to determine the number of military aircraft to be procured, given conflicting expenditure, budget and effectiveness goals. This method is demonstrated via a case example in which the solution results are presented.     

Vector two-point functions in maximally symmetric spaces

We obtain massive and massless vector two-point functions in maximally symmetric spaces (and vacua) of any number of dimensions. These include de Sitter space and anti-de Sitter space, and their Euclidean analogsS ⁿ andH ⁿ. Our method is based on a simple way of constructing every possible maximally symmetric bitensorT _a...bc...d(x, x) which carries tangent-space indicesa...b atx andc...d atx.