In making inference on the relation between failure and exposure histories in the Cox semiparametric model, the maximum partial likelihood estimator (MPLE) of the finite dimensional parameter, and the Breslow estimator of the baseline survival function, are known to achieve full efficiency when data is available for all time on all cohort members, even when the covariates are time dependent. Wh...

SOLTRAN is a flexible computer model for the direct solar beam intensity spectrum at the earth's surface. It has been derived by combining the extra-terrestrial solar spectrum with the atmospheric transmittance spectrum. Application of SOLTRAN to the calculation of the potential efficiency of photovoltaic cells demonstrates the effect of atmospheric absorption bands. These bands prevent unequiv...

The paper outlines a method to determine the sedimentation efficiency in modernized tanks with incorporated lamella packets. The method takes into account the properties of the suspension (density, viscosity, solid phase distribution) and tank design parameters – flow intensity and settling surface. Several types of grain size distributions are considered: the log-normal distribution and genera...

We investigate the influence of the energy levels on the power conversion efficiency of a P3HT:PCBM and a MEH-PPV:PV bulk heterojunction cell. We calculate the upper-limit for the efficiency, and make realistic assumptions to predict efficiencies obtainable in the near future. The ideal position of the energy levels of donor and acceptor are obtained from these calculations, giving an idea how ...

A metallic coupler is proposed to interface a silicon on insulator (SOI) waveguide with a narrow hybrid plasmonic waveguide (200× 200 nm). The device operation is investigated and optimized to attain the best tradeoff between the mode confinement and the propagation loss. Calculations reveal that a high confinement and low loss of the energy is achieved from a silicon slab waveguide into the di...

Laser fusion simulations are carried out for DT and D- He pellets by using a hydrodynamic code including heating from all charged reaction products and neutrons. It is shown that the inclusion of the side reactions and heating from all reaction products in the fuel pellets have an appreciable effect on the plasma temperature, the ICF drive energy requirement, fusion gain and the ignition c...

Oceanic depth profiles of plankton respiration are described by a power function, RCO2 = (RCO2 )0(z/z0) , similar to the vertical carbon flux profile. Furthermore, because both ocean processes are closely related, conceptually and mathematically, each can be calculated from the other. The exponent b, always negative, defines the maximum curvature of the respiration–depth profile and controls th...

Large industrial aerodynamic calculations are nowadays performed indifferently on parallel vector computers or on clusters of SMPs. From a software design point of view it is crucial to ensure the best possible sustained megaflops rate on both platforms while for sake of minimal labour effort it is important to maintain only one source code. In this paper we describe software techniques that ha...

Oceanic depth profiles of plankton respiration are described by a power function, RCO2 = (RCO2 )0 (z/z0) b similar to the vertical carbon flux profile. Furthermore, because both ocean processes are closely related, conceptually and mathematically, each can be calculated from the other. The exponent, b, always negative, defines the maximum curvature of the respiration depth-profile and controls ...