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Microwave-absorptive polymer composite materials provide protection against interference to communication systems caused by microwave-inducing devices. Microwave-absorptive polymer composites were prepared from polylactic acid (PLA) biocomposite blended with oil palm empty fruit bunch (OPEFB) fiber and commercial Iron oxide (Fe2O3) as filler using the melt-blending method. The composites characterization was carried out using the scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The coefficient of reflection S11 and coefficient of transmission S21 of the composites for various Fe2O3 filler percentages were determined using a rectangular waveguide in connection with microwave vector network analyser (HP/Agilent model PNA N5227). These coefficients were then used to calculate microwave-absorption properties (in decibels). XRD analysis showed that increasing amounts of reinforced material (Fe2O3) reduces the crystallinity of the composites. SEM data indicated that Fe2O3 filler ratio increased in the composites, and adhesion to the cellulose fiber grew gradually until the highest percentage of filler was added. The complex relative permittivity and relative permeability were obtained within the broad frequency range of 8–12 GHz at room temperature for various percentages of filler and were measured by the transmission/reflection method using a vector network analyser. Fe2O3 embedment in OPEFB/PLA was observed to have resulted in enhancing the dielectric and magnetic properties. The values of permittivity and permeability increased with increasing Fe2O3 filler content. Theoretical simulation studied the relation between e′ and e″ of the relative complex permittivity in terms of Cole-Cole dispersion law. The result indicated that the processes of Debye relaxation in Fe2O3/OPEFB/PLA, the unique dielectric characteristics of Fe2O3 cannot be accounted for by both the Debye dipolar relaxation and natural resonance. Results further showed that the material transmission, reflection, and absorption properties could be controlled by changing the percentage of Fe2O3 filler in the composites.

This paper engages in a microhistory of international law, grounded in the contests surrounding theMuscat Dhowscase brought by Great Britain against France in 1905. At the heart of the case was the question of whether the French consul had the right to grant flags and navigation passes to dhows from the southern Omani port of Sur that were suspected of transporting slaves. The case became foundational to studies of the law of the sea, and the ruling is still cited in footnotes in law school textbooks. Buried in the case's proceedings, however, are a series of petitions by the dhow captains that give historians a window into the legal imaginaries of Indian Ocean mariners in an age of empire. Through a close reading of the petitions, I explore how captains located themselves within an imperial legal geography, and appropriated legal technologies—passes and flags—to help them shape the legal possibilities of a changing political and economic seascape. I argue that the claims the captains articulated and the practices they engaged in at sea reveal a maritime legal culture at work, one animated by a long history of encountering regional and global empires at sea. Their documentary practices illuminate how they engaged in and domesticated a body of international law, and illustrate how the regime manifested itself in an ocean that ran thick with legal idioms.

This is an ambitious book that the author deserves high praise for writing. Thomas McDow draws on a broad range of sources in a number of different languages and from far-flung archives and librari...

This paper presents the electromagnetic interference properties of multi-walled carbon nanotubes (MWCNTs) as a novel nano-reinforcement filler in poly (lactic acid) (PLA)/poly (ethylene glycol) (PEG) polymer matrix that was prepared via melt blending mode. Plasticization of PLA was first carried out by PEG, which overcomes its brittleness problem, in order to enhance its flexibility. A waveguide adapter technique was used to measure the dielectric properties &epsilon, r, and S-parameters reflection (S11) and transmission (S21) coefficients. The dielectric properties, microwave attenuation performances, and electromagnetic interference shielding effectiveness (EMISE) for all the material under test have been calculated over the full X-Band (8&ndash, 12 GHz) due to its importance for military and commercial applications. The prepared samples were studied while using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Fourier transforms infrared spectroscopy (FTIR), mechanical properties measurements, as well as thermogravimetric analysis (TGA). The results showed that the dielectric properties increased with increased multi-walled carbon nanotubes (MWCNTs) filler, as well as the shielding effectiveness of the MWCNT/PLA/PEG nanocomposites increased with the increasing of MWCNTs. The highest SE total value was found to be 42.07 dB at 12 GHz for 4 wt% filler content. It is also observed that the attenuation values of the nanocomposites increased with an increase in MWCNTs loading, as well as the power loss values for all of the samples increased with the increase in MWCNTs loading, except the amount of the transmitted wave through the nanocomposites.

This paper presents a study on the structural, morphological and elastic properties of erbium oxide nanoparticles doped bio-silicate borotellurite glass system fabricated using the technique of melt-quenching with chemical compositional formula {[(TeO2)0.7 (B2O3)0.3]0.8 (SiO2)0.2}1−y (Er2O3 NPs)y where 0.01 ≤ y ≤ 0.05. The objective of the work was to study the some elastic and thermal parameters associated with non-destructive ultrasonic technique, with the aim of utilizing the glasses for erbium doped fiber amplifier application. Various measurements and Characterizations techniques which includes density and molar volume measurements, energy dispersive X-ray fluorescence, X-ray diffraction (XRD), Fourier transform infrared (FTIR), Transmission electron microscopy and Pulse-echo technique were carried out in this study. The density values for the glasses increased from 4.1900 to 4.6003 gcm−3 with the addition of 1–5% of Er2O3 NPs in the glass structure. The increase can be ascribed to increase in the overall molar weight of the glass due to incorporation of heavy Er3+ ions. The XRD patterns revealed no presence of sharp peaks with the observed broad hump around 2θ = 20–30° indicating the glassy and amorphous nature of the studied glasses. The FTIR spectra showed absorption with peaks around 1362–1385 cm−1, 1221–1250 cm−1, 655–689 cm−1 and 602–630 cm−1 wave number ranges, indicating the presences of H3BO3, SiO4, BO3, TeO3 and TeO4 structural units in the glass system. The microstructural nature observed in the glass morphology showed nanoparticle agglomerations in the glasses. The ultrasonic velocities, elastic moduli, microhardness, Poisson ratio, softening and Debye’s temperatures, thermal expansion coefficient as well as other important parameters were calculated from the density and ultrasonic data. The values of the ultrasonic velocities, elastic moduli, Debye’s temperature, softening temperature, thermal expansion coefficient and the acoustic impedance increased with increase in the Er2O3 NPs concentration.

Aerospace Industry is making breakthrough development with Quantum System. Along with, security of the system is the most promising issue. Where Quantum Physics play a vital role in the security and challenges of Aircraft, a lot of cryptographic algorithms used for securing the Aerial communication. In this research, we discuss the contribution of Airbus Company in aerospace industry and adaptation of Quantum System for solving future challenges. One of the most awakening issues is the security of Aerospace industry, where Quantum Cryptography algorithms are used. Here, we are trying to replace QKD with HD-QKD, because during data/key transmission photon efficiency rate effects. By using the BB84 Protocol with HDQKD, we tried to enhance photon rate efficiency, and proposed a HDQKD based Model for Aerial and Non Aerial Communication. So, Quantum Cryptography with HDQKD techniques enhances the security of Aerospace industry more firmly.

IEEE 802.15.4 is a standard for low rate wireless personal area network (i.e. LR-WPANs) and ZigBee based wireless sensor networks (WSNs). This research presents an analysis of clustering based hybrid mobility in IEEE 802.15.4 PAN. This paper unfolds: (1) performance analysis of IEEE 802.15.4 from little to expansive scale PAN; (2) utilization of clustering mobility on remote node prompts to loss of packets. The hybrid mobility designs (directed and undirected mobility) on a remote node has been researched and claimed to contrast in a variable size network. The simulation results expound the relationship of the arbitrary mobility on remote sensor node with influences over the performance metrics of the network, for example, the end-to-end delay, packet loss, and throughput.

Mobile cloud computing MCC provide to a certain extent many settlement like battery timing, memory, consistency and scalability. Though, still there some sort essential elements, those should be discussed and make their implementation effective in MCC. Some of its most prominent challenges are Security of Wireless Devices, Cloud Privacy and certainty, data bandwidth and transfer rate, synchronizing and managing the data, battery capacity, Energy Efficiency (EE), and heterogeneity. In this research we present a detailed overview of Mobile Cloud Computing and proposed a Heterogeneity Model for Cloud Computing. The main problem in MCC is security privacy and trust, so we are trying to solve this issue using RSA Cryptographic Algorithms.

Endogenous agmatine has a significant role in learning and memory processes as a neurotransmitter. Various studies described the physiological role of endogenous agmatine in learning and memory of multiple cognitive tasks suggesting elevated levels of agmatine during the learning process in the rat brain. Dietary intake of choline showed correlation with cognitive functions in human subjects and treatment with choline supplements validated the ability to diminish learning and cognitive impairment dementias.36 Albino rats were equally divided into three groups previously: a) control-water, b) Test I - AlCl3 (100 mg/Kg body weight), and c) Test II - Forced swim stress (FSS) for 14 days. On the next day of AlCl3 and FSS last administration, animals were allocated into further three groups and received the following treatments: a. water was given orally to the control group, b. Agmatine (100 mg/Kg Body Weight) group, and c. Choline (100 mg/Kg Body Weight) group for the next 14 days. Behaviors were assessed in Light/Dark Box, Open Field, Novel Object Recognition Test (NOR), T Maze Test, and Morris Water Maze Test.Animals administered with agmatine demonstrated increased time spent in bright areas of light/dark box and square crossed while improved spatial memory in Morris water maze and T maze test and enhanced discrimination of novel object in NOR were observed in learning and memory paradigms along with choline.The present study determines that agmatine at the dose of (100 mg/kg body weight) attenuates memory and cognitive impairment in comparison with choline supplements.

Mandibular third molar is the most frequently impacted tooth (prevalence 16.7% to 68.6%) [1] and is commonly removed by surgery. The surgical intervention is associated with moderate to severe postoperative pain, swelling and trismus. [2,3] Pain is generated by release of inflammatory endogenous chemical mediators such as bradykinin and prostaglandin. [4] Different anti-inflammatory and antibacterial drugs and insertion of cones or drains saturated with analgesic and antibiotic agents have been used by oral and maxillofacial surgeons for pain control. [5] Drugs of different classes with different mode of actions may also be combined to optimize their analgesic efficacy and tolerability. [6] The efficacy of paracetamol-codeine (PC) combination has proven a superior pain control over paracetamol alone but with associated complications of codeine like sedation, dizziness, nausea, vomiting and constipation. [7] Paracetamol has also been combined with tramadol (PT), an atypical weak opioid with a dual mechanism of action inclusive of a μ-opioid receptor activation and an enhancement of serotonin and norepinephrine transmission, for moderate to severe pain. [8] A significantly lower incidence of constipation, vomiting and other side effects have been reported with PT combination as compared to PC combination. [9] PT combination has not been widely reported for use in oral surgery. our study has several limitations. As one may argue that there is no control group receiving placebo, considering the surgical procedure being invasive one, placebo control group was not even possible. Also in our study, pain was evaluated after 24 hours post op and was not evaluated at different time points, with which more accurate results could have been achieved.

Er2O3 doped silica borotellurite glasses were synthesized using the melt-quenching technique with a chemical compositional formula (1 – x){(SiO2)0.2 [(B2O3)0.3 (TeO2)0.7]0.8} (Er2O3)x. Using the XRD, FTIR, UV–Vis, and photoluminescence spectroscopies, the structural, optical and spectroscopic properties of the glasses were studied. The absorption spectra and the refractive index, penetration depth, extinction coefficient, absorption coefficient, dielectric constant, optical conductivity for the glasses were presented. The absorption and emission cross-sections, cross-sectional gain, effective bandwidth, and bandwidth quality factor were also calculated using the UV–Vis data. Photoluminescence and the upconversion luminescence of the glasses were presented for pump wavelengths of 350 nm and 540 nm respectively. The studied glasses presented a high refractive index with values between 2.452 and 2.5153. The emission cross-section, effective bandwidth, bandwidth quality factor increased respectively from 3.53 × 10–22 to 1.3637 × 10–20 cm2, 66.3–103 nm, and 3.636 × 1028–91.095 × 1028 cm3 with increase in the Er3+ ions concentration in the glass system. The synthesized glasses exhibits a high-quality up-conversion emissions around 397.5 nm, 426 nm, and 475 nm from an excitation due to a pump of 540 nm wavelength. Furthermore, a high-quality luminescence emission around 543 nm, 500 nm, 475 nm and 425 nm from an excitation due to a pump of 350 nm wavelength was observed. Considering the values of the glasses refractive index, dielectric behaviour, absorption and emission cross-sections, effective bandwidths and other parameters presented, the synthesized glasses possess great potential for optoelectronic, laser and Erbium dope fibre amplifier (EDFA) applications.

The study of the Middle East is witnessing a sea change (excuse the maritime metaphor). The traditional geographic poles of Middle East studies (Turkey, Egypt, the Levant, and Iraq) stand firm, but are now facing a challenge from places once thought to be peripheral to the historiography: namely, South Arabia and the Gulf. The rising tide of scholarship on those areas is due in large measure to the opportunities that now present themselves in resituating them historically, and thinking about them as part of broader transoceanic worlds. This reorientation has made itself clear in the growing number of publications that wrestle with the Middle East's maritime frontiers—especially in the sister disciplines of history and anthropology. Here I limit myself to just one of those disciplines—history—and chart out the waves of contact between historians of the Middle East and the Indian Ocean. I offer no argument, but rather a survey of where the field has been and the opportunities that lie ahead.

Our goal in this paper is introduce the action of hesienberg group on finite dimention manifold M. the interrelation ship between hesienberg group and the finite dimention manifold M is an old and vast subject. To simplify this treatment we work with liealgebra defined on a finite dimention manifold M, the heisenberg group forned an action over these liealgebra on finite manifold M. No doubt, anotion on the heisnberg group can constitute avery important situation in the a differential finite manifold M, therefore, our work presents a key role mainly in some properties and characteriztions of the action of heinberg group on finite dimention manifold M, and also we study characterization on the relation between heisnberg group and finite dimention manifold M, then we introduce an an action of heisnberg group by the tensor product of the two repersentation which are (Acolyte groups) on hom (V2, V1’) be the tensor product of two representations of heisberg group and construct the definition of AC-heisnberg group, also study the properties of this action.

In this study, a nanocomposite of reduced graphene oxide (RGO) nanofiller-reinforcement poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) matrix was prepared via the melt blending method. The flexibility of PLA was improved by blending the polymer with a PEG plasticizer as a second polymer. To enhance the electromagnetic interference shielding properties of the nanocomposite, different RGO wt % were combined with the PLA/PEG blend. Using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction, the structural, microstructure, and morphological properties of the polymer and the RGO/PLA/PEG nanocomposites were examined. These studies showed that the RGO addition did not considerably affect the crystallinity of the resulting nanomaterials. Thermal analysis (TGA) reveals that the addition of RGO highly improved the thermal stability of PLA/PEG nanocomposites. The dielectric properties and electromagnetic interference shielding effectiveness of the synthesized nanocomposites were calculated and showed a higher SE total value than the target value (20 dB). On the other hand, the results showed an increased power loss by increasing the frequency and conversely decreased with an increased percentage of filler.

Cognitive radio, ad hoc networks' applications are continuously increasing in wireless communication globally. In vehicles' environment, cognitive radio technology with mobile ad hoc networks (MANETs) enables vehicles to monitor the available channels and to effectively function in these frequencies through sharing ongoing information with drivers and different frameworks to enhance traffic safety on roads. To fulfill the computational storage resources’ limitations of a specific vehicle, Vehicular Cloud Computing (VCC) is used by merging VANET with cloud computing. Cloud computing requires high security and protection because authenticate users and attackers have the same rights in VCC. The security is enhanced in CRVANETs, but the distributed nature of cloud unlocks a door for dissimilar attacks, such as trust modal, data security, connection fault and query tracking attacks. This paper proposes an effective and secured blockchain scheme-based distributed cloud architecture in place of conventional cloud architecture to secure the drivers’ privacy with low cost and on-demand sensing procedure in CRVANETs ecosystem.

In the modern era where the use of computer systems in software houses is mandatory and in various organizations has increased, it has given rise to the level of stress of employees working for hours at the system as well. Employees working in software houses are prone to have increased stress and anxiety level. It is important to detect the stress level of the employees so that various solutions can be applied in the working environment to get a better output. This paper would be beneficial for detecting the stress level of employees working on the computer using various inputs i.e. heart rate, pupil contraction, facial expressions, skin temperature, blood pressure, age and number of hours working on the computer. This research would indicate the raised level of stress of employees and this indication can be used to increase the yield of the quality of work and satisfaction of employees working in a particular organization. According to the levels of stress, within the working environment, during break hours various steps can be taken as a solution and applied during break hours of employees to ensure maximum satisfaction and the improved quality of work.

The internet of medical things (IoMT) is playing a substantial role in improving the health and providing medical facilities to people around the globe. With the exponential growth, IoMT is having a huge influence in our everyday life style. Instead of going to the hospital, patient clinical related data is remotely observed and processed in a real time data system and then is transferred to the third party for future use such as the cloud. IoMT is intensive data domain with a continuous growing rate which means that we must secure a large amount of sensitive data without being tampered. Blockchain is a temper proved digital ledger which provides us peer-to-peer communication. Blockchain enables communication between non-trusting members without any intermediary. In this paper we first discuss the technology behind Blockchain then propose IoMT based security architecture employing Blockchain to ensure the security of data transmission between connected nodes.

Data security is becoming more important in cloud computing. Biometrics is a computerized method of identifying a person based on a physiological characteristic. Among the features measured are our face, fingerprints, hand geometry, DNA etc. Biometric can fortify to store the cloud server using bio-cryptography. The Bio-cryptography key is used to secure the scrambled data in the cloud environment. The Bio-cryptography technique uses fingerprint, voice or iris as a key factor to secure the data encryption and decryption in the cloud server. In this paper, the security of the biometric system through cloud computing is discussed along with improvement regarding its performance to avoid the criminal to access the data. Biometric is a genuine feature for the cloud provider. Cryptography algorithm will be explained using blockchain technology to overcome security issues. The blockchain technology will provide more protection through cryptographic keys to secure biometric data.

The present review deals with the fundamental approaches that cover the numerical solutions of singular and hypersingular integrals. The contribution of this work is to highlight and gather the most important background with the current modification of such work and provide the reader with an accurate image of today’s knowledge regarding the approximate solutions of singular integrals. The review provides a clear understanding of various numerical approaches from the 1960s up to the present day. Some interesting applications in physics and engineering are also given.

SDN (Software Defined Networking) is an architecture that aims to improve the control of network and flexibility. It is mainly connected with open flow protocol and ODIN V2 for wireless communication. Its architecture is central, agile and programmatically configured. This paper presents a security analysis that enforces the protection of GUI by requiring authentication, SSL/TLS integration and logging/security audit services. The role based authorization FortNOX and ciphers like AES and DES will be used for encryption of data and improving the security of SDN environment. These techniques are useful for enhancing the security framework of the controller.

The preparation of chemically reduced graphene oxide (rGO) and the optimization of epoxy resins&rsquo, properties using micro or nanofillers are now common practices. rGO nanoparticles (60 nm) based on an epoxy resin polymer were prepared at the concentrations of 0, 1, 2, 3, 4, and 5% weight percentage with fixed 6-mm thicknesses. The dielectric properties of the composites were measured by the reflection/transmission technique in connection with a vector network analyser (VNA) at a frequency range of 8&ndash, 12 GHz. The microwave absorption and shielding effectiveness properties were calculated by using the reflection S11 and transmission S21 results. The microstructure and morphology of the polymer and the rGO/cured epoxy composites were studied by field emission scanning electron microscopy (FE-SEM), Fourier-transform infrared (FT-IR) spectroscopy, and the X-ray Diffraction (X-RD) technique for characterizing crystalline materials. The dielectric and other properties of the rGO/cured epoxy composites were investigated based on the filler load and frequency. It was found that the applied frequency and the filler concentrations affected the dielectric properties of the rGO/cured epoxy composites. The results showed that the introduction of rGO particles to the composites increased their dielectric properties smoothly. The study of the dependence on frequency of both the dielectric constant &epsilon, &prime, and the dielectric loss &epsilon, &Prime, showed a decrease in both quantities with increasing frequency, indicating a normal behaviour of the dielectrics. Cole&ndash, Cole plots were drawn with &epsilon, and &epsilon, A theoretical simulation in terms of the Cole&ndash, Cole dispersion law indicates that the Debye relaxation processes in the rGO/cured epoxy composites are improved due to the presence of the rGO filler. Moreover, with the addition of rGO as a filler into the Epoxy matrix, it now exhibits promise as a lightweight material for microwave absorption as well as an effective electromagnetic interference (EMI) shielding material.

A new algorithm is presented to provide a general solution for a first type Hyper singular Integral Equation (HSIE). The singular integral has been converted into a regular form by cancelling the singularity and then transforming it into a system of algebraic equation based orthogonal poly- nomials. We applied the convergence method presented by (Obaiys, 2013) to conform the numerical solution of the regularized Hadamard equation, which has shown an absolute agreement with the exact solution within small values of n. The proposed method has been examined by various HSIEs where the displacement function satisfies the HO§lder-continuous first derivative. Such equations are particularly important inmany physics and engineering problems, such as fracture mechanics, acoustics and elasticity.

The dielectric properties of composites based on nickel-zinc-ferrite (NZF) filler can be improved by the addition of various types of materials. Amongst others, ferrite–polymer composites have been subjected to wide range of research, due to their extensive applications: electromagnetic interference shielding, microwave absorption, electrodes and sensors. In this study, Ni0.5Zn0.5Fe2O4 (NZF) was prepared via conventional solid-state method. While NZF–OPEFB-PCL composite has been prepared via the mechanical milling mode and then characterized by X-ray powder diffraction. Dielectric properties of the composite, such as dielectric constant, loss factor and loss tangent were measured at different filler percentage over a wide range of frequency (0.20MHz-20GHz). An open ended coaxial probe connected to a vector network analyzer (VNA) was utilized for the evaluation of dielectric properties for materials and composites under test at the room temperature. Both dielectric constant and loss factor values increased due to the filler increment in the polymer matrix, where the composition of 15% NZF gives the extreme permittivity value at the used microwave frequency. Furthermore, the obtained results confirmed that dielectric properties of the composite can be controlled by the proper loading and the wise filler choosing. The adjusted properties support the purpose of polymer composite materials for microwave and communicational applications.

In this work, Bio-composite of oil palm empty fruit bunch fibre (OPEFB)-filler andpolycaprolactone (PCL)-polymer has been prepared and characterized. The functional groups and morphology of theprepared samples were characterized by Fourier transform infrared spectroscopy (FT-IR). By using the NicholsonRoss-Weir(NRW) mode, both of real and imaginary relative permittivity values of the samples were obtainedsimultaneously from the reflection and transmission coefficient measurements of the materials. Whereas, theattenuation with the field distribution at the waveguide filled with a sample were considered by using the FiniteElement Method (FEM). The magnitude of the reflection and transmission (R/T) coefficients of the composite withdifferent filler percentages were measured using rectangular waveguide in conjunction with a microwave vectornetwork analyzer (VNA) in X-band range of frequency. The computations of the S-parameters were achieved byusing the FEM technique along with NRW mode. Then, the obtained results were compared with the measured R/Tcoefficients. Relative error results nominated the FEM mode due to its highly accurate results than the other method. Keywords: Microwave measurements, OPEFB, PCL, Bio-composite

Regression testing is considered to be one of the most costly, time-taking, and important activity which is performed in an environment with a number of certain restrictions for ensuring the validity of a modified software. Therefore, it becomes necessary to pick the sequence of test cases which is correct as well as it should have the ability to traverse all the faults taking minimum execution time. Prioritizing the test cases helps to achieve performance requirements in which important test cases are executed before than those having lower degree of importance. Studies have shown that prioritization approaches based on test factors like Importance, Volatility, Complexity, Fault Rate, Time, Coverage have good results and also the approaches based on intelligent techniques like Ant Colony, genetic algorithms, have been very promising. Hence, this paper presents a hybrid of these two approaches which first generates the test cases based on the priorities, which are assigned using test factors, and then, the best sequence having least execution time and highest fault rate is calculated by the Ant Colony Optimization algorithm.