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Co-occurrence of extreme ozone and heat waves in two cities from Morocco
Get PDFTemperature is the first meteorological factor to be directly involved in leading ozone (O3) extreme events. Generally, upward temperatures increase the probability of having exceedance in ozone adopted thresholds. In the global climate change context more frequent and/or persistent heat waves and extreme ozone (O3) episodes are likely to occur during in coming decades and a key question is about the coincidence and co-occurrence of these extremes. In this paper, using 7 years of surface temperature and air quality observations over two cities from Morocco (Casablanca and Marrakech) and implementing a percentile thresholding approach, we show that the extremes in temperature and ozone (O3) cluster together in many cases and that the outbreak of ozone events generally match the first or second days of heat waves. This co-occurrence of extreme episodes is highly impacted by humidity and may be overlapping large-scale episodes
Application of Phylogenetic Analysis in the Study of Mitochondrial Genetic Diseases
Get PDFMitochondrial genetic diseases are receiving increasing attention. However, the common case-control methods are susceptible to genetic background, population stratification, data quality and other factors that may lead to false positive results. The field of genetic diseases has not been paid enough attention. Therefore, this paper reviews this method and promotes the extensive and in-depth use of mitochondrial gene
A detailed study on LDPC encoding techniques
Get PDFThis survey deals with LDPC encoding techniques. Different types of error detection and correction codes have been studied. BHC codes, Turbo code, LDPC Codes, Hamming codes are some of the vast classes of codes. Low Decoding complexity and efficient throughput are the achieved by using LDPC codes. Robert G.Gallager introduced this code so LDPC codes are Gallager code. After then Mackay and Neal in 1995 rediscovered LDPC codes because of its bit error performance. It consist of sparse of ones ie., low density of one’s because of this property decoding is simple. The major setback in LDPC codes are Encoding Complexity. WLAN (IEEE 802.11n) and MIMO OFDM are some of the applications of code. This code is a class of forward error correction (FEC) technique that exhibits capacity of impending near Shannon’s limit. LDPC codes are well identified for their capacity-approaching performance The LDPC codes have been selected as forward error correction in application including digital video broadcasting (DVBS2), 10 Gigabit Ethernet (10GBASE-T) broadband wireless access (Wi-Max), wireless local area network, deep-space communications
Choose the Appropriate Cluster Head for Decrease Energy Consume in Wireless Sensor Networks Based on Gravitational Emulation Local Search Algorithm
Get PDFNew Wireless Sensor Networks (WSN), is the new generation of real-time embedded systems with limited computation, energy and storage which have variety usage, especially when that is not possible using traditional networks. Given that, in this networks energy problem is important major challenge, using Clustering model can be considered as a solution to overcome this problem. In this instruction, sensor nodes grouped in a set of cluster and pick out a central node for Cluster Head (CH) node. Choose the appropriate cluster, reduce energy consumption in these networks, as a result increase networks lifetime. Hence, in this study, unlike previous studies, used Gravitational Emulation Local Search Algorithm (GELS), for clustering and select appropriate CH. This method is based on three descriptors of energy, dispersion and centrality of nodes, and simulations indicate, where the CH only selected based on local data set, significantly increase network lifetime
Bridge monitoring utilizing handheld devices
Get PDFNatural Frequencies of structures is an elegant intrinsic property that is essential for many Civil Structural applications, as Structural Health Monitoring and Simulation Modeling. The physically tangible relation between the frequency of the structures and its dynamic characteristics was the impetus for using different time/frequency based methods to quantify this fundamental property. Unfortunately, the disruption effect of noise requires incorporating advanced sensors, that provide signals with a low noise-intensity, to accurately identify the fundamental frequencies of the structure. This article solves this bottleneck via exploiting the Stochastic Resonance (SR) phenomena to extract the fundamental frequencies of a bridge using an acceleration recorded by a conventional portable sensor as the sensor implemented in small portable accelerometer. The portable accelerometer device has an M9 motion coprocessor designed mainly for tracking human activities. Human activities have an exaggerated amplitude when it is compared to the structural responses. Therefore, if an iPhone device is used to record the response of the structure (for example a bridge) the structure response will be swamped by severe surrounding noise because of its small amplitude. Therefore, in this vein, the SR phenomena has been employed to use rather than suppress the noise to magnify the feeble bridge response in the recorded acceleration and hence identify the corresponding frequency. The fidelity of the proposed approach has been verified using the data of a field experiment. The bridge frequencies are identified first using conventional vibration analysis, thereafter, the portable accelerometer has been attached to the bridge rail to record the bridge vibration under the passing traffic. The recorded data has been processed using a new Developed Underdamped Pinning Stochastic Resonance (DUPSR) technique to quantify the bridge frequency
Short beam strength and flexural behavior of GFRP laminates embedded with short carbon fibers having notch
Get PDFThis paper examines the mechanical performance of eight-layered GFRP laminate embedded with short carbon fibers (SCF). Eight layered GFRP samples are prepared using press molding machine at 40 KN pressure. Notched samples (1 mm deep) at specific position from the center are tested, the doping of SCF is done to evaluate the improvement in mechanical properties using reinforcement at three different proportions 0, 1, 2 and 5 wt.%. The GFRP samples are prepared as per ASTM D2344 and ASTM D7264 for short beam strength (SBS) and flexural and respectively. Samples are tested using Hounsfield HK-50 universal testing machine (UTM) with 50KN capacity at room atmospheric conditions. Results of the experimental analysis justified that the improvement in mechanical properties with increase in doping percentage of SCF while at highest doping value i.e. 5 wt.% mechanical properties reduced
Physicho and electrochemical characterization of PVC incorporated ZP composite membrane and their important parameters through applying TMS equation
Get PDFThe synthetic organic-inorganic composite membranes have enormous applications in the field of filtration and purification processes. The newly synthesized PVC (polyvinyl chloride) incorporated ZP (zinc phosphate) composite membrane is used as a barrier for the transportation of some strong electrolyte solutions like KCl, NaCl and LiCl. The composite material which used to make the membrane was qualitatively synthesized by sol-gel method of material synthesis. To characterize the structural and thermal properties of membrane there are different techniques like FTIR, XRD, TGA/DTA, SEM-EDX, LCR have been used. By characterizations it is clear that the material has crystalline nature, thermally stable and no breakages or cracks are found on membrane the surface. The electrochemical observation was done by potentiometer, which shows that the membrane is cation selective. To determine the charge density of membrane Teorell-Meyer-Sievers method is used. The observed potential and charge density of the incubated membrane follows KClNaCl>LiCl order respectively. The other important parameters like transport number, mobility ratio, charge effectiveness are also calculated by observed potential values
The effect of foaming agent on mechanical and physical properties of Polypropylene
Get PDFIn this study, Polypropylene (PP) foam materials were used with injection parameters such as melting, molding and injection temperatures. To produce foam materials, chemical foaming agents were used, and added to polymer materials as 1wt.%, 1.5wt.%, 2wt.%, 2.5wt.%, 3wt.%. The mechanical properties of foam samples were determined based on the parameters. Cell morphology characterization such as cell diameter, cell count, skin layer thickness and cell density, and mechanical properties such as tensile and impact strength of polymer foams were examined.Generally, the closed-cell foam structure was obtained. The most important parameters affecting the cell morphology have been injection pressure, melt temperature and amount of foaming agent. With increasing the amount of foaming agent, cell density increased, foam density and mechanical properties decreased
FREE SEMIGROUP PRESENTATIONS
Get PDFLet and be two free semigroups. We define external direct product of two free semigroups as an ordered pair of words such that and .We investigate the presentations of external direct product of free semigroups, state and prove under some conditions that the external direct product of two finitely generated free semigroups is finitely generated, also the external direct product of two finitely presented free semigroups is finitely presented.
Green technology awareness: A case of Malaysia
Get PDFIn the context of technology, the organization should be well fitted to implement green practice. Environmental practices have been well studied but only a few studies have presented the green innovation practices of corporate firms in Malaysia. This study focused on the awareness of green practices which were concerted upon organizational (Training Program), environment (Government Regulation & Policies) and individual context (Knowledge). A total of 108 questionnaires were returned out of 200. Reliability analyses were applied to test reliability of the instrument. Meanwhile, regression analysis was applied to determine the predicted factors for green practices towards the awareness of green practices. The results of the analysis indicated knowledge of employees as the most influencing factors to the awareness of green practices. For the practicality of this study, green technology is anticipated to be well implemented when these practices are understood