M-GEAR: Gateway-Based Energy-Aware Multi-Hop Routing Protocol for WSNs

In this research work, we advise gateway based energy-efficient routing protocol (M-GEAR) for Wireless Sensor Networks (WSNs). We divide the sensor nodes into four logical regions on the basis of their location in the sensing field. We install Base Station (BS) out of the sensing area and a gateway node at the centre of the sensing area. If the distance of a sensor node from BS or gateway is less than predefined distance threshold, the node uses direct communication. We divide the rest of nodes into two equal regions whose distance is beyond the threshold distance. We select cluster heads (CHs)in each region which are independent of the other region. These CHs are selected on the basis of a probability. We compare performance of our protocol with LEACH (Low Energy Adaptive Clustering Hierarchy). Performance analysis and compared statistic results show that our proposed protocol perform well in terms of energy consumption and network lifetime.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

One-minute rain rate statistics prediction using Ito-Hosoya model in Malaysia

This paper investigates one-minute rain rate in Kuala Lumpur, Malaysia predicted based on Ito-Hosoya model. The model is categorized into meteorological based model as it receives as input local meteorological parameter. The best part about this model is it does not requires measured rain rate data to be converted into one-minute, instead it depends on long-term meteorological parameter values which widely available from various sources. In this paper, the local meteorological parameters are extracted from TRMM database which are average accumulation rainfall (from TMPA 3B43) and thunderstorm ratio (from TRMM PR 3A25 and TMI 3A12). The result shows that this model could be promising for use in Malaysia region as it produces better performance compared to the ITU-R model

EFFICIENCY OPTIMIZATION OF AN OPENLOOP CONTROLLED PERMANENT MAGNET SYNCHRONOUS MOTOR DRIVE USING ADAPTIVE NEURAL NETWORKS

When a Permanent Magnet Synchronous Machine (PMSM) is utilized for applications where high dynamic performance is not a requirement, a simple open loop control strategy can be used to control them. PMSMs however are prone to instability when operated open loop in a variable speed drive, particularly at mid-frequencies/speeds. This paper presents an open-loop control strategy based on a direct adaptive neural network controller is developed for efficiency optimization of open-loop controlled PMSM drive. Stability constraints of the drive system which was previously reported are used to maintain both stable and highly efficient operation of the drive system. The adopted neural network can be viewed as a method for nonlinear adaptive system identification, relying on pattern recognition of stability limits and maximum obtainable efficiency. Results from computer simulation show that a stable and highly efficient operation can be maintained for the drive system under study irrespective of load and supply variations. The obtained results are also found in correlation with previously reported experiments and observations

ASSESSMENT OF SEASONAL VARIABILITY FOR WIND SPEED AND SIGNIFICANT WAVE HEIGHT USING SATELLITE ALTIMETER OVER MALAYSIAN SEAS

Malaysia is located in the equatorial region and experienced climate hot, humid and rainy throughout the year. These have brought four monsoon seasons to Malaysia which can be categorised as Northeast monsoon, Southwest monsoon, First-inter monsoon and Second-inter monsoon. Although Malaysia is surrounded by large scale marine resources, the lack of understanding in seasonal variability has affected the spatial and temporal analysis. Thus, this study will highlight the assessment of seasonal variability of wind speed and significant wave height over the Malaysian seas. For more than two decades satellite altimeter data were used to generate a prolonged trend of regional ocean wind speed and significant wave height in order to study the monsoons in Malaysia. A set of wind speed and significant wave height data are compared with the in-situ measurement to validate the accuracy of the wind speed and significant wave height observation using the satellite altimeter. Two selected buoys were using as benchmarks and assessed using the statistical analysis by conducting a root mean square error and a correlation calculation. Seasonal variations assessment is conducted with significance to analyse the monsoon effect towards the wind speed and significant wave height condition. As a result, both ocean parameters present a good value of root mean square error and positive correlation which were 0.7976 (wind speed) and 0.92 (significant wave height), which proves the measurement from satellite altimeter is reliable to use. In addition, the seasonal variation assessment illustrates during the Northeast monsoon, each part of the Malaysian seas experienced with great wind speed and significant wave height

Impacts des eaux polluées sur la croissance, les teneurs en chlorophylles et substances organiques dans les feuilles de deux Poaceae

Dans le contexte actuel de conservation de la biodiversité, les questions liées à la protection de l’environnement sont essentielles et vitales. La ville de Douala fait partie des villes du Cameroun où la pollution des eaux est mieux ressentie. Une étude comparative des paramètres de croissance notamment, le nombre des feuilles, la surface foliaire, la hauteur et le diamètre des tiges, les teneurs en chlorophylles et substances organiques dans les feuilles de Zea mays et Eleusine indica poussant en milieu pollué et non pollué a été réalisée. Quelques paramètres physiques de l’eau polluée ont été analysés et certains paramètres physico-chimiques ont été acquis. Les résultats montrent que les valeurs moyennes du nombre de feuilles, des hauteurs et des diamètres des tiges de Zea mays et Eleusine indica sont plus élevées en milieu pollué comparativement au milieu naturel. Les concentrations moyennes des chlorophylles (a + b) dans les feuilles de ces deux espèces rencontrées au voisinage du marécage pollué sont significativement plus faibles que celles obtenues en milieu non pollué. Les teneurs en glucides et lipides (exprimés en % de matière sèche) dans les échantillons de feuilles de Zea mays et Eleusine indica qui poussaient en milieu pollué ont diminué alors que celles des protides ont augmenté.© 2010 International Formulae Group. All rights reserved.Mots clés : chlorophylle, croissance, Eleusine indica, feuille, pollution, Zea mays

The efficacy of an extraoral scavenging device on reduction of splatter contamination during dental aerosol generating procedures: an exploratory study

Correction to: The efficacy of an extraoral scavenging device on reduction of splatter contamination during dental aerosol generating procedures: an exploratory study. Br Dent J (2020). https://doi.org/10.1038/s41415-020-2288-

Mini-DSAEK for Macro Corneal Perforations

PURPOSE: We present a technique that preserves good vision in paracentral macroperforations and avoids challenges of tectonic lamellar or penetrating keratoplasty in eyes with poor visual potential. METHOD: A wet laboratory was implemented for mini-Descemet stripping endothelial keratoplasty to seal macroperforations ab interno. This included a suture support technique designed to prevent graft herniation. We also present 3 cases who were treated successfully with this technique. RESULTS: The laboratory test confirmed that mini-Descemet stripping endothelial keratoplasty can successfully seal macroperforations without the need of large incisions. The minidisc is introduced through the perforation, and a double mattress suture prevents graft herniation. The technique allowed us to preserve 20/15 unaided vision in a case with paracentral macroperforation. It also restored eye globe integrity and achieved long-term stability in 2 cases with limbal stem-cell deficiency. CONCLUSIONS: Mini-Descemet stripping-automated endothelial keratoplasty technique can be an alternative approach to avoid poor visual outcomes of tectonic keratoplasty in paracentral perforations. It also offers host tissue preservation in eyes with high risk of rejection for tectonic grafts