Most methods used in the field of linear and nonlinear time series analysis assume stationarity of the considered data. Non–stationarity is very likely to lead to wrong results. This is especially true for tests for nonlinearity. A common approach is to split the time series into segments which can be considered nearly stationary and perform individual tests. But for short time series or not to...

I remember the time when I had no problem with spam. There simply was no spam at a bit of history that time. It was truly wonderful. Unfortunately, these happy times didn’t last too long—slowly but inevitably spammers got me. I now receive about 30–40 unwanted junk e-mails a day. And that’s, according to some individuals, not too many. Well, tell you what: when I reach the limit of, let’s say. ...

Let ‖ · ‖ denote the distance to the nearest integer and, for a prime number p, let | · |p denote the p-adic absolute value. In 2004, de Mathan and Teulié asked whether infq≥1 q · ‖qα‖ · |q|p = 0 holds for every badly approximable real number α and every prime number p. Among other results, we establish that, if the complexity of the sequence of partial quotients of a real number α grows too ra...

We study the population dynamics of lytic viruses which replicate slowly in dividing host cells within an organism or cell culture, and find a range of viral replication rates that allows viruses to persist, avoiding extinction of host cells or dilution of viruses at too rapid or too slow viral replication. For the within-host competition between viral strains with different replication rates, ...

Several reports have demonstrated associations between falls and nocturia in the elderly. However, little information is available regarding other age groups. This study evaluated the relationship between the frequency of nocturia and falls in men using a large, population-based survey in Korea, and the results were adjusted for various confounding factors. Data from a 2011 Korean community hea...

In friction stir welding (FSW), the real contact conditions between tool and workpiece range of strain rates experienced remain quite unclear. this work, a coupled 3D thermo-mechanical numerical model was used to simulate FSW process. A Parametric finite element analysis evolution conditions, temperatures with processing parameters, dimensions base material plastic properties conducted. The abl...