Performance Analysis in Heterogeneous Networks with Spatiotemporal Traffic and Scheduling

In this work, we consider interference performance under direct data transmission in a heterogeneous network. The heterogeneous network consists of K-tier base stations and users, whose locations follow independent Poisson point processes (PPPs). Packet arrivals of users follow independent Bernoulli processes. Two different scheduling policies, round-robin (RR) and random scheduling (RS), are employed to all the Base Stations (BS). The universal frequency reuse mode is adopted to reveal actual spectrum reuse. By leveraging stochastic geometry and queueing theory, the interference interactions of the proposed network are accurately modelled. Accurate expressions for the mean packet throughputs of the network under universal frequency reuse mode are derived. The simulation results explore the optical bias factors in heterogeneous networks to maximize the mean packet throughput. Under a given user density, by changing BS densities, we achieved a certain mean packet throughput level.

Sunflower breeding for resistance to the new races of broomrape (Orobanche cumana Wallr.) in Romania

The actual spectrum of the broomrape races in Romania has changed. The study of the sunflower differential set for the broomrape races, under natural and artificial infestation demonstrated the existence of a new spectrum of these races. We assigned the new race with F and the corresponding gene for resistance, with Or6 gene. In our breeding work for resistance to this new race of the parasite, the results we have this far achieved in introducing genes for resistance to broomrape into sunflower value inbred lines are important. Our use of convergent crosses based on transgressive recombination has proven very suitable as a method for incorporating resistance genes into standard sunflower lines. The χ² test has shown the inheritance of resistance to be controlled by a single dominant gene. The results have also confirmed that the presence of broomrape in plant materials can be diagnosed very early in the season using a modification of the Pancenko method. An assessment made 40 days after sowing showed that broomrape plants were for the most part well developed by that time.

Pursuit of quantum monodromy in the far-infrared and mid-infrared spectra of NCNCS using synchrotron radiation

Quantum monodromy in NCNCS produces this predicted complex rotational and rovibrational spectral pattern, which guided our search for the actual spectrum.

A Critical Look at the Use of Design Spectrum Shape for Seismic Risk Assessment

The effects of using design spectrum shape over actual response spectra on earthquake damage estimates has been investigated. A series of numerical simulations were conducted to estimate the expected damage. The simulations were conducted with four different spectral shapes, two different ground-motion prediction equations (GMPEs) and three different soil classes. As a result of the numerical simulations, it was observed that the use of design spectrum shape leads to over- or underestimation of damage estimates relative to those obtained from the actual spectrum computed using GMPE. The damage estimates were observed to be sensitive to the selected design spectrum shape, the GMPE used to compute the spectral values, the soil type, and the fundamental period of the building typology. It was also observed that Eurocode- and IBC-type design spectrum shapes led to significantly different damage estimates compared to one another.

Model of Noise Source for HF Interference Calculation in a Converter Station

For high-frequency (HF) interference in an HVDC converter station, the modeling of the noise source which causes interference with the power line carrier (PLC) remains a problem. Based on the profound analysis of the basic principles on which HF noise in PLC band is produced during the commutation process, the equivalent model of the HVDC valve with a snubber circuit is applied to the simulation of the GUI-GUANG HVDC project in PSCAD/EMTDC. Then spectrum plots of the noise source in the frequency domain are obtained by FFT analysis of the voltage waveforms gained from the simulation. Through analyzing the spectrum characteristics of the noise source in various operating modes, the main factors influencing the level of HF noise are found. Furthermore, a modified empirical model used to calculate the level of the noise source is introduced, with particular explanation of the physical quantities used in the model. The spectra of the noise source gained from the modified empirical model and from the simulation are compared with an actual spectrum based on the GUI-GUANG HVDC project. The results show that the modified empirical model can meet the requirement of HF interference calculation.