MASSIVE MIMO FOR HIGH-SPEED TRAIN COMMUNICATION SYSTEMS

With the current development in wireless communications in high-mobility systems such as high-speed train (HST), the HST scenario is accepted as among the different scenarios for the fifth-generation (5G). Massive Multiple-Input-Multiple-Output (MIMO) systems, which are equipped with tens or hundreds of antennas has become an improved MIMO system which can assist in achieving the ever-growing demand of data for 5G wireless communication systems. In this study, the associated 5G technologies, as well as the equivalent channel modeling in HST settings and the challenges of deploying massive MIMO on HST, was investigated The channel model was modeled using the WINNER II channel model. With regrads, the proposed non-stationary IMT-A massive MIMO channel models, the essential statistical properties such as the spatial cross-correlation function (CCF), local temporal autocorrelation function (ACF) of the massive MIMO channel model using different propagation scenarios such as open space, viaduct and cutting was analyzed and investigated. The results from the simulations were compared with the analytical results in other to show that the statistical properties vary with time as a result of the non-stationarity of the proposed channel model. The agreement between the stationary interval of the non-stationary IMT-A channel model and the HST under different propagation scenarios shows the efficiency of the proposed channel model. Based on findings; the impact of the deployment of a large antenna on the channel capacity should be thoroughly investigated under different HST propagation scenario. Also, more HST train propagation scenarios such as the tunnel, hilly terrain, and the station should be considered in the non-stationary IMT-A massive MIMO channel models

Phyto-metals screening of selected anti-diabetic herbs and infused concoctions

Objective: To determine the levels of some selected heavy metals in both the selected anti-diabetic herbal plants and infused concoctions for diabetes treatment. Methods: Ten anti-diabetic plant samples: pawpaw leaves (Carica papaya), bitter melon leaves (Momordica charantia), holy basil leaves (Ocimum sanctum), bitter leaf (Vernonia amygdalina), ginger rhizome (Zingiber officinale), garlic (Allium sativum), African red pepper fruits (Capsicum frutescens), negro pepper grain (Xylopia aethiopica), cashew leaves (Anacardium occidentale) and onion bulb (Allium cepa) were evaluated for heavy metals. These were digested using standard methods and analyzed for manganese, copper, nickel, chromium, zinc, cadmium and lead using atomic absorption spectrophotometer. The infused concoctions (I and II) prepared from these medicinal herbs administered to diabetic patients were also analyzed for these heavy metals. Concoction I contained all the plants and honey with the exception of Momordica charantia and Ocimum sanctum which constituted concoction II with water only. The data obtained were subject to descriptive (mean and standard deviation) and inferential (ANOVA and DMRT) statistics. Results: Chromium and nickel levels were below detection limits in concoction I while manganese [(0.11 ± 0.01) μg/g] and zinc [(0.09 ± 0.01) μg/g] were detected in concoction II. Honey contained manganese [(0.10 ± 0.01) μg/g] and nickel [(0.70 ± 0.01) μg/g]. The anti-diabetic medicinal herbs and infused concoctions (I and II) were observed to contain heavy metals below the compared limits. Conclusions: The study thus shows that the herbs and concoctions are safe from the heavy metals considered. However, right dosage of the anti-diabetic concoctions should always be considered to prevent possible chronic side effects from bio-accumulation of heavy metals