Software defined networking for wireless sensor networks: a survey

One main feature of Software Defined Networking (SDN) is the basic principle of decoupling a device’s control plane from its data plane. This simplifies network management and gives network administrators a remarkable control over the network elements. As the control plane for each device within the network is now implemented on a separate controller, this reliefs individual devices from the overhead caused by complex routing. Specifically, this feature has been shown to be extremely beneficial in the case of resource-constrained Wireless Sensor Networks (WSNs). By keeping the control logic away from the low-powered nodes, the WSNs can resolve their major issues of resource underutilisation and counter-productivity. This paper highlights the importance of adopting the SDN in the WSNs as a relatively new networking paradigm. This is introduced through a comprehensive survey on relevant networking paradigms and protocols supported by a critical evaluation of the advantages and disadvantages of these mechanisms. Furthermore, open research issues and challenges are pointed out shedding a light on future innovations in this field

A study of non-profit leaders\u27 risk-taking propensity and managerial leadership styles

Risks are an inherent part of life and in nonprofit organizations (NPOs) in particular. Nonprofit organizations struggle to respond to changes imposed by external and internal environmental influences. These influences revolve around the myriad social, cultural, political, environmental, and economic changes and their attendant challenges. The NPOs now face yet another challenge, which is a significant managerial leadership deficit. The purpose of this quantitative study is to examine whether nonprofit leaders’ risk-taking propensity (RTP) is associated with their managerial leadership styles (MLS). Furthermore, the study will examine if age, gender, level of education, size of an organization, and number of employees have any effect on a leader’s style and his or her propensity for risk-taking. The study utilized a quantitative correlational research design. This was appropriate, as the purpose of this study was to measure the correlation between two variables. Of the 82 NPOs invited to participate, 125 leaders responded positively to the request. The 73 valid survey responses received were complete. This represents a 58.4% valid response rate for this study. Findings indicated that nonprofit leaders who participated in this correlational study considered themselves to utilize transformation leadership style, and the most common risk domain is the ethical domain. Also, a positive significant relationship between leader’s risk-taking propensity and his or her transformation leadership style

Survey and comparison of different classification techniques for select appropriate classifier of image

In human visual system, visual object classification is easy and effortless but in computer vision systems it is extremely hard Because of the various images of different objects within a specific class may have together with the various viewing conditions had led to have a serious problem. If some images have noisy contents or it contains blurry data, thus it is very hard to classify these types of images. Images processing introduces several techniques which be able to classify the data, but if image is blurry or noisy so they can not able to give the acceptable results. In this survey discuss the main classification methods consider, Supervised learning and unsupervised learning. The major motivation of this survey is to gives a brief comparison among different images classification techniques and methods. Finally, it is determined method that more accurately if an image contains blurry or noisy data

EFFECT OF DIFFERENT SOLVENTS ON THE CHEMICAL COMPOSITION AND ANTI-DIABETIC ACTIVITY OF ACACIA ARABICA AND ZIZYPHUS MAURITIANA

The current study was designed to investigate the effect of solvents on chemical composition and antidiabetic activity of Zizyphus mauritiana and Acacia Arabica extracts. Total five solvents were used for this purpose (100% methanol, 50% aqueous methanol, 100% ethanol, 50% aqueous ethanol and aqueous). The data obtained from the investigation was subjected to the statistical analysis by using analysis of variance technique. The present study revealed that maximum antioxidant activity was attributed to Acacia arabica (96.53 ± 0.46%) followed by Zizyphus mauritiana (94.33 ± 0.52% by 50% aqueous ethanol extracts). Maximum total phenolic content of both Zizyphus mauritiana and Acacia arabica (670.83 ± 1.46 mg GAE/100g and 934.34 ± 0.89 mg GAE/100g) were shown by 50% aqueous ethanol extracts while maximum total flavonoid content (146.36 ± 0.81 mg QE/100 g, 172.52 ± 0.99 mg QE/100 g) was exhibited by 50% aqueous ethanol extract. The maximum (IC 50= 49.63 ± 0.12 µg/mL) antidiabetic activity was found in aqueous extract of Acacia arabica while in Zizyphus mauritiana the aqueous extract indicated excellent (IC 50= 46.90 ± 0.23 µg/mL) antidiabetic activity

The Plant Regulator Soaking Seeds and its Reflections on Growth and Yield Quality of Wheat

A greenhouse pot experiment was carried out during November 2013 to May 2014. Winter wheat grains (Triticum aestivum L.), cultivars Abu-Ghureb and Cham6 were used to investigate the effect of soaking seeds in 300ppm of benzyl adenine (BA) or daminozide solutions for 6 hours before sowing vegetative, yield components, leaf chlorophylls and some chemical constituents of seeds. BA treatment led to significant increases in tiller number plant-1, chlorophyll b, P, dry gluten, N and protein contents of seeds. It also led to significant decreases in number of leaves plant-1. In addition, the number of tillers plant-1, shoots dry weight plant-1, P, N and protein contents of seeds were increased by daminozide treatment, but this caused a significant decrease in the plant height, number of leaves plant-1 and flag leaf area. Number of grains plant-1, weight of 1000 grains and grains yield were significantly increased by both treatments. Cultivar variability was noted for some tested parameters. The tall, N, P content and protein content of Abu-Ghureb cultivar were higher significantly than Sham6. The case was opposite with number of leaves plant-1, flag leaf area, shoots dry weight plant-1, spike length and grain number plant-1

Energy efficient resource allocation in 5G hybrid heterogeneous networks: A game theoretic approach

Millimeter wave (mmWave) technology integrated with heterogeneous networks (HetNets) has emerged as a new wave to overcome the thirst for higher data rates and severe shortage of spectrum. In this paper, we consider the uplink of a hybrid HetNet with femtocells overlaid on a macrocell, and formulate a two layer game theoretic framework to maximise the energy efficiency (EE) while optimising the network resources. The outer layer allows each femtocell access point (FAP) to maximise the data rate of its users by selecting the frequency band either from the sub-6 GHz and the mmWave. The solution to this non-cooperative game can be obtained by using pure strategy Nash equilibrium. The inner layer ensures the energy efficient user association method subject to the minimum rate and maximum transmission power constraints by using dual decomposition approach. Simulation results show that the proposed hybrid HetNet scheme exploiting the mmWave frequency band improves the sum-rate and EE in comparison to the scenario where all the networks operate at sub-6 GHz frequency band. The performance can further be enhanced by incorporating the power control mechanism

A proteomic investigation of Aspergillus carbonarius exposed to yeast volatilome or to its major component 2-phenylethanol reveals major shifts in fungal metabolism

The use of yeast-derived volatile organic compounds (VOCs) represents a promising strategy for the biological control of various plant pathogens, including mycotoxin-producing fungi. Previous studies demonstrated the efficacy of the low-fermenting yeast Candida intermedia isolate 253 in reducing growth, sporulation, and ochratoxin A biosynthesis by Aspergillus carbonarius MPVA566. This study aimed to investigate whether the inhibitory effect of the yeast volatilome is solely attributable to 2-phenylethanol, its major component, or if a synergistic effect of all volatilome components is required to achieve an effective control of the fungal growth and metabolism. Microbiological methods, HPLC measurements and a UPLC-MS/MS approach were used to investigate the metabolic profile of A. carbonarius MPVA566 at different growing conditions: standard incubation (control), exposed to C. intermedia 253 volatilome, and incubation in the presence of 2-phenylethanol. Both yeast volatilome and 2-phenylethanol succeeded in the macroscopic inhibition of the radial mycelial growth, along with a significant reduction of ochratoxin A production. Functional classification of the fungal proteome identified in the diverse growing conditions revealed a different impact of both yeast VOCs and 2-phenylethanol exposure on the fungal proteome. Yeast VOCs target an array of metabolic routes of fungal system biology, including a marked reduction in protein biosynthesis, proliferative activity, mitochondrial metabolism, and particularly in detoxification of toxic substances. Exposure to 2-phenylethanol only partially mimicked the metabolic effects observed by the whole yeast volatilome, with protein biosynthesis and proliferative activity being reduced when compared with the control samples, but still far from the VOCs-exposed condition. This study represents the first investigation on the effects of yeast-derived volatilome and 2-phenylethanol on the metabolism of a mycotoxigenic fungus by means of proteomics analysis. Chemical compounds studied or used in this article: 2-Phenylethanol (PubChem CID: 6054); ochratoxin-A (PubChem CID: 442530); sodium dodecyl sulfate (PubChem CID: 3423265); dithiothreitol (PubChem CID: 446094); phenylmethylsulfonyl fluoride (PubChem CID: 4784); iodoacetamide (PubChem CID: 3727); ammonium bicarbonate (PubChem CID: 14013); acetic acid (PubChem CID: 176); and acetonitrile (PubChem CID: 6342). - 2019 The AuthorsThis publication was made possible by NPRP grant # 8-392-4-003 from the Qatar National Research Fund (a member of Qatar Foundation). The findings achieved herein are solely the responsibility of the authors.Scopu

Minimizing the Transaction Time Difference for NOMA-Based Mobile Edge Computing

Non orthogonal multiple access (NOMA) and mobile edge computing (MEC) are evolving as key enablers for fifth generation (5G) networks as this combination can provide high spectral efficiency, improved quality-of-service (QoS), and lower latency. This letter aims to minimize the transaction time difference of two NOMA paired users offloading data to MEC servers by optimizing their transmission powers and computational resources of severs using a successive convex approximation method. The equalization of transaction time for paired users reduces the wastage of both frequency and computational resources, and improves effective throughput of the system to 19% on average

Focused Ion Beam Tomography

To study the fundamental effect of shape and morphology of any material on its properties, it is very essential to know and study its morphology. Focused ion beam (FIB) tomography is a 3D chemical and structural relationship studying technique. The instrumentation of FIB looks like that of the scanning electron microscopy (SEM), but there is a major difference in the beam used for scanning. For SEM, a beam of electrons is used with scanning medium whereas in FIB, a much focused beam of ions is used for scanning. FIB can be used for lithography and ablation purposes, but due to advancements and high-energy focused beam, it is nowadays being used as a tomographic technique. Tomography is defined as imaging by sectoring or cross-sectioning any desired area. The hyphenation of FIB with energy-dispersive spectrometry or secondary ion mass spectrometry can give us elemental analysis with very high-resolution 3D images for a sample. This technique contributes to acquaintance of qualitative and quantitative analyses, 3D volume creations, and image processing. In this chapter, we will discuss the advancements in FIB instrumentation and its use as 3D imaging tool for different samples ranging from nanometer (nm)-sized materials to micrometer (μm)-sized biological samples

Joint optimization of Age of Information and Energy Efficiency in IoT Networks

Age of information (AoI) refers to the freshness of data generated by a status-update system. It is a crucial metric in networks such as Internet of things (IoT), specially when the underlying application demands fresh update. In environmental monitoring and smart agriculture, apart from the importance of AoI, energy efficiency (EE) becomes inevitable owing to network longevity. This paper studies an IoT network where the end devices transfer their information to a central gateway residing on a moving platform such as a tractor, which collects information from a large number of sensors in an agri-field. An optimal trajectory of the mobile reader is proposed using a modified nearest neighbor algorithm to gather the information from randomly distributed sensors. A clustering algorithm is also used to cluster the data in such a way that the overall EE of the network is maximized keeping a desired AoI and outage probability