The Effects of MIMO Antenna System Parameters and Carrier Frequency on Active Control Suppression of EM Fields

In this paper we propose a new approach employing adaptive active control algorithms combined with a Multiple-Input Multiple-Output (MIMO) antenna system to suppress the electromagnetic field at a certain volume in space (e.g., at the human head). We will investigate the effects of the size and number of MIMO antenna elements on the system performance and test the algorithms at different carrier frequencies (e.g., GSM bands and UMTS)

On the Uniqueness of Solution of Magnetostatic Vector‐potential Problems by Three‐dimensional Finite‐element Methods

In this paper, particular attention is paid to the impact of finite‐element approximation on uniqueness and to approximations implicit in finite element formulations from the uniqueness requirements standpoint. It is also shown that the flux density is unique without qualifications. The theoretical and numerical uniqueness of the magnetic vector potential in three‐dimensional problems is also given. This analysis is restricted to linear, isotropic media with Dirichlet Boundary conditions. As an interesting consequence of this analysis it is shown that, under usual conditions adopted in obtaining three‐dimensional finite‐element solutions, it is not necessary to specify div Ā in order that Ā be uniquely defined

Identification and visualization of cellulase activities from Neurospora crassa

To elucidate the nature of cellulase activities found in Neurospora crassa, we analyzed the induced spent culture medium for the components of the cellulase enzyme complex

Risky Sexual Behavior and Associated Factors Among High School Students in Gondar City, Northwest Ethiopia

According to World Health Organization (WHO), youth are young people within 15-24 years old. Studies reported that more than half of all new HIV infections occur among people between the ages of 15 and 24 years. Institution based quantitative cross-sectional study was conducted among high school students in Gondar city. Multistage sampling technique was employed to recruit study participants. Data were collected using pretested structured self-administered questionnaire. Data were entered in Epi Info version 7 and analyzed using SPSS version 21. Descriptive statistics were computed to describe important variables in relation to the outcome variable, Binary and multivariable logistic regressions were used to identify independent predictors of the outcome variable. The overall prevalence of risky sexual behavior was 12.8%. Two out of five sexually active respondents ever had unprotected sexual intercourse. Ever used alcohol ((AOR, 3.53 95% CI (1.73-7.19)), had no parental monitor (AOR, 12.21 95% CI (6.55-22.78), ever watched pornographic film (AOR, 2.24 95% CI (1.15-4.35), had no parental discussion on sexual and reproductive health issues (AOR, 2.57 95% CI (1.36-4.85) and peer pressure (AOR,2.50, 95%CI (1.20-5.21), were factors which significantly increases the odds of risky sexual behavior among youth. Risky sexual behavior among high school students in Gondar city administration was very high and worrisome; so that collaborated effort is needed from parents, schools, health facilities and health policy makers to bring healthy sexual behavior among school youth

Investigation and Scaling of Hydrogen Production by Klebsiella sp. ABZ11 for Optimal Yield and the Kinetics of Batch Fermentation Process

The slow metabolism of bacteria at low temperatures affects the catalytic efficiency of enzymes and productivity. This article investigates the use of a psychrotolerant bacteria (Klebsiella sp. ABZ11) for biohydrogen production, yield and scaling at optimal temperature, pH and glucose in a batch fermentation process within a 2-liter bioreactor using Response Surface Methodology (RSM) to report the process performance. The results show 33.5°C, pH 6.75 and 9.15 g glucose as the optimal conditions. Scale-up yielded 137.56 mol/L biohydrogen, 22.13% more than production under optimized conditions. Biomass grew at 0.081/h and doubled in 17 h with 0.71 g cells to reach maximum production. Compared to 0.062/h, 22 h with 0.87 g cells in optimal condition to achieve maximum biohydrogen production. This result shows the potential of biohydrogen production using Antarctic psychrotolerant bacteria at mesophilic temperature

The cranking formula and the spurious behaviour of the mass parameters

We discuss some aspects of the approach of the mass parameters by means of the simple cranking model. In particular, it is well known that the numerical application of this formula is often subject to ambiguities or contradictions. It is found that these problems are induced by the presence of two derivatives in the formula. To overcome these problems, we state a useful ansatz and we develop a number of simple arguments which tend to justify the removal of these terms. As soon as this is done, the formula becomes simpler and easier to interpret. In this respect, it is shown how the shell effects affect the mass parameters. A number of numerical tests help us in our conclusions.Comment: version 3 corrigendum of the ansatz of section V, corrigendum of the legend of Fig3. Submission = text file + 5 figure