Fade Depth Prediction Using Human Presence for Real Life WSN Deployment

Current problem in real life WSN deployment is determining fade depth in indoor propagation scenario for link power budget analysis using (fade margin parameter). Due to the fact that human presence impacts the performance of wireless networks, this paper proposes a statistical approach for shadow fading prediction using various real life parameters. Considered parameters within this paper include statistically mapped human presence and the number of people through time compared to the received signal strength. This paper proposes an empirical model fade depth prediction model derived from a comprehensive set of measured data in indoor propagation scenario. It is shown that the measured fade depth has high correlations with the number of people in non-line-of-sight condition, giving a solid foundation for the fade depth prediction model. In line-of-sight conditions this correlations is significantly lower. By using the proposed model in real life deployment scenarios of WSNs, the data loss and power consumption can be reduced by the means of intelligently planning and designing Wireless Sensor Network

Textural properties of infra red dried apple slices as affected by high power ultrasound pre-treatment

Drying is a process frequently used in food industry, often based on the use of conventional methods using heat exchange by conduction or convection. This kind of method may lead to quality loss in structure, texture and  sensory characteristics of final products. Consequently, the need for research of new drying methods arises.  One of such methods is power ultrasound aided drying. The aim of this work was to investigate the impact of  high power ultrasound pre-treatment on drying rate and textural properties of the infra red dried apple slices.  Ultrasound device working at a frequency of 24 kHz with a power capacity of 200 W was used for ultrasound  pre-treatment. The amplitudes used for ultrasonic pre-treatment were 50 and 100%. The results showed that  the use of different amplitudes of ultrasound reduces the time of drying and allows elimination of more water  from the apple slices. Usage of 50 and 100% of ultrasonic amplitude in great extent shortened the duration of  drying (up to 40%). The results showed that hardness of samples gradually increases (50% amplitude –  97.260 N; 100% of amplitude – 217.90 N) with increase of ultrasound intensity. As a result, hardness of  untreated apple slices (41.037N) was significantly lower (p < 0.05).Key words: High power ultrasound, amplitude, drying, apple

Household, community, sub-national and country-level predictors of primary cooking fuel switching in nine countries from the PURE study

Introduction. Switchingfrom polluting (e.g. wood, crop waste, coal)to clean (e.g. gas, electricity) cooking fuels can reduce household air pollution exposures and climate-forcing emissions.While studies have evaluated specific interventions and assessed fuel-switching in repeated cross-sectional surveys, the role of different multilevel factors in household fuel switching, outside of interventions and across diverse community settings, is not well understood. Methods.We examined longitudinal survey data from 24 172 households in 177 rural communities across nine countries within the Prospective Urban and Rural Epidemiology study.We assessed household-level primary cooking fuel switching during a median of 10 years offollow up (∼2005–2015).We used hierarchical logistic regression models to examine the relative importance of household, community, sub-national and national-level factors contributing to primary fuel switching. Results. One-half of study households(12 369)reported changing their primary cookingfuels between baseline andfollow up surveys. Of these, 61% (7582) switchedfrom polluting (wood, dung, agricultural waste, charcoal, coal, kerosene)to clean (gas, electricity)fuels, 26% (3109)switched between different polluting fuels, 10% (1164)switched from clean to polluting fuels and 3% (522)switched between different clean fuels