Excited multiplets of Eu in GaN

A method to calculate the multiplet states of lanthanide impurities in solids is presented. This approach is based on a semi-empirical density functional method which includes corrections to account for the correlation and spin-orbit coupling of the 4f electrons. Specific multiplet states of the rare earth are produced by constraining the system. This approach is then used to investigate some of the properties of substitutional europium impurities in gallium nitride, reproducing the relative energy of two multiplets, and discussing a potential excitation mechanism for these centers

Choice Valuation of Traffic Restrictions: Perspectives on Noise, Pollution and Congestion Preferences

This paper focuses on the choice valuation of traffic restrictions while entering Lisbon city based on individual preferences for noise, pollution and congestion. The analysis employs a questionnaire distributed in 2007 to ascertain the significant characteristics of traveling to Lisbon, with the aim of curbing the number of cars that enter the city daily. A random parameter logit model is used to analyze the characteristics (e.g. individual characteristics, motivations, type of transport used) that are associated with the probability of individuals supporting a fee on private cars entering the city. The model also takes into account the uncontrolled heterogeneity of the data. Some policy implications are also presented.Transportation; Lisbon; Mixed Logit Model; Public Policy.

How a Student’s Ideal College Experience Influences Where They Live

A student survey was created to understand how students decide where to live during college. Interviews with ISU Department of Housing administrators were also conducted to understand how administrators adapt to changes in student demographics and desires. From these interviews, I found that administrators have a good understanding of student decision-making with regard to housing. Perceptions of monetary cost were overestimated in their effect on years spent on campus, but every other factor was well assessed. Students are more motivated by their desired college experience, which varies by grade classification, major, and initial satisfaction with on-campus housing. As students progress in their college education, they desire more diverse experiences. Engineering students live on campus longer than business students due to different valuations of convenience and the full college experience. The more positive a student’s initial on-campus experience, the more likely they will return to on-campus housing. This research will help provide the Department of Residence with potential groups to target when they are concerned about re-contracting and ideas to improve overall student satisfaction with on-campus housing

Samarium Magnetism Studied on SmPd2Al3 Single Crystal

In this paper, specific features of Sm magnetism in an intermetallic compound have been studied. For this purpose, a high-quality single crystal of SmPd2Al3 was grown and subjected to detailed measurements of specific heat, magnetization, ac susceptibility, and electrical resistivity with respect to temperature and a magnetic field applied along the principal crystallographic directions. SmPd2Al3 magnetism was found to be strongly anisotropic with the easy-magnetization direction along the c axis where the main magnetic features are concentrated. The a-axis response remains weak, paramagneticlike, even in the magnetically ordered state. Ferromagnetism with TC=12.4 K has been indicated by all the measured physical properties. At lower temperatures, three successive order-order phase transitions have been observed on the temperature dependence of the specific heat as three anomalies: at 3.4, 3.9, and 4.4 K, respectively. The low-temperature magnetization data can be understood within a scenario that considers the antiferromagnetic ground state as being gradually destroyed through a series of four metamagnetic transitions at 0.03, 0.35, 0.5, and 0.75 T, as detected in the 1.8 K magnetization data. The experimental data are discussed together with the results of electronic-structure and crystal-field calculations from first principles, which were performed as an important part of the study for comprehension and explanation of the observed behavior of the SmPd2Al3 compound