Analysis of Noisy Evolutionary Optimization When Sampling Fails

In noisy evolutionary optimization, sampling is a common strategy to deal with noise. By the sampling strategy, the fitness of a solution is evaluated multiple times (called \emph{sample size}) independently, and its true fitness is then approximated by the average of these evaluations. Previous studies on sampling are mainly empirical. In this paper, we first investigate the effect of sample size from a theoretical perspective. By analyzing the (1+1)-EA on the noisy LeadingOnes problem, we show that as the sample size increases, the running time can reduce from exponential to polynomial, but then return to exponential. This suggests that a proper sample size is crucial in practice. Then, we investigate what strategies can work when sampling with any fixed sample size fails. By two illustrative examples, we prove that using parent or offspring populations can be better. Finally, we construct an artificial noisy example to show that when using neither sampling nor populations is effective, adaptive sampling (i.e., sampling with an adaptive sample size) can work. This, for the first time, provides a theoretical support for the use of adaptive sampling

Majorana Dark matter with B+L gauge symmetry

We present a new model that extends the Standard Model (SM) with the local B+L symmetry, and point out that the lightest new fermion $\zeta$, introduced to cancel anomalies and stabilized automatically by the B+L symmetry, can serve as the cold dark matter candidate. We study constraints on the model from Higgs measurements, electroweak precision measurements as well as the relic density and direct detections of the dark matter. Numerical results reveal that the pseudo-vector coupling of $\zeta$ with $Z$ and the Yukawa coupling with the SM Higgs are highly constrained by the latest results of LUX, while there are viable parameter space that could satisfy all the constraints and give testable predictions.Comment: 17 pages, 4 figures, minor revision, more references adde

Vurdering av fôrverdi av korn og belgvekster til drøvtyggere ved bruk av in vitro gassproduksjon

This thesis consists of a literature background and laboratory experiment. The literature review contains knowledge of raw ingredients, ruminal digestion of nutrients and feed evaluation methods of ruminants. Feed quality crucially effect either milk yield or growth rate of ruminants. Both in vivo and in situ methods are largely limited on feed evaluation. Therefore, the purpose of experiment was to characterize different feed ingredients and explore the relationship between chemical composition and feed degradation using in vitro gas production technique. Nine different feeds and (or) ingredients (total mixed ration, barley, wheat, maize, oats, peas, horse bean, pea starch and horse bean starch) were milled to 1 mm particle size. The experiment was designed in 2 batches * 9 feed samples * three modules for each feed. Rumen fluid was collected from two non-lactating dairy cows with rumen cannula. Feed samples were incubated in buffered rumen fluid using in vitro gas production techniques. Gas production kinetics for 48 h incubation was measured and organic matter digestibility and metabolizable energy were calculated based on gas production and chemical composition of the feeds/ingredients.Denne avhandling består av en litteraturdel og egne undersøkelser. Litteraturdelen tar for seg råvarevurdering, fordøyelse av næringsstoffer og metoder for fôrmiddelvurdering til drøvtyggere. Fôrkvaliteten påvirker melkeyting og vekst hos drøvtyggere. Både in vivo og in situ metoder har sine begrensninger i vurdering av fôrverdi til drøvtyggere. Formålet med egne undersøkelser var å vurdere forskjellige fôrtyper med hensyn på fôrverdi ut fra kjemisk sammensetning og nedbrytning av fôr ved hjelp av in vitro gassproduksjonsteknikk. Ni ulike fôrtyper og/eller fôrprøver (blandet fôrrasjon, bygg, hvete, mais, havre, erter, åkerbønner, ertestivelse og åkerbønnestivelse) ble malt på 1 mm sold. Disse ble undersøkt med in vitro gassproduksjon i 2 batcher med tre gjentak for hver fôrtype. Vomvæske ble tatt fra to ikke-lakterende kyr via ei vomkanyle og blandet med buffer. Fôrprøvene ble inkubert i bufret vomvæske og in vitro gassproduksjon ble målt over 48 timer. Gassproduksjonskinetikk for de 48 timene, og fordøyelighet av organisk stoff (OMD), ble beregnet. Omsettelig energi (ME) ble beregnet basert på gassproduksjon og kjemisk sammensetning av fôrprøvene.M-F