Performance analysis of 2 level DWT-SVD based non blind and blind video watermarking using range conversion method

Microsystem Technologies - The recent availability of inexpensive digital recording and storage devices have created an environment to obtain, replicate and distribute digital content without any...     

Bioactive Chemical Constituents from the Brown Alga Homoeostrichus formosana

A new chromene derivative, 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-hydroxy-2,6-dimethyl-2H-chromene (1) together with four known natural products, methylfarnesylquinone (2), isololiolide (3), pheophytin a (4), and β-carotene (5) were isolated from the brown alga Homoeostrichus formosana. The structure of 1 was determined by extensive 1D and 2D spectroscopic analyses. Acetylation of 1 yielded the monoacetylated derivative 2-(4'',8''-dimethylnona-3''E,7''-dienyl)-8-acetyl-2,6-dimethyl-2H-chromene (6). Compounds 1–6 exhibited various levels of cytotoxic, antibacterial, and anti-inflammatory activities. Compound 2 was found to display potent in vitro anti-inflammatory activity by inhibiting the generation of superoxide anion (IC₅₀ 0.22 ± 0.03 μg/mL) and elastase release (IC₅₀ 0.48 ± 0.11 μg/mL) in FMLP/CB-induced human neutrophils.     

A fully integrated low-IF CMOS GPS radio with on-chip analog image rejection

A fully integrated Global Positioning System (GPS) radio is presented. Low-IF architecture was used for a high level of integration and low power consumption. An on-chip analog image-reject filter provides 18 dB of image-noise rejection to prevent noise figure (NF) degradation. With image rejection performed in the analog radio, a single-path (nonquadrature) output was used. The integrated synthesizer only requires an off-chip phase-locked loop-filter to function. Implemented in a 0.35-/spl mu/m 2P4M CMOS process, the integrated radio has a chip area of 9.5 mm/sup 2/. The radio operates over a wide range of voltage and temperature, from 2.2 to 3.6 V and from -40/spl deg/C to +85/spl deg/C and consumes 27 mW from a 2.2-V supply. The receiver has 4 dB NF.     

Highly basic CaO nanoparticles in mesoporous carbon materials and their excellent catalytic activity

Highly basic CaO nanoparticles immobilized mesoporous carbon materials (CaO-CMK-3) with different pore diameters have been successfully prepared by using wet-impregnation method. The prepared materials were subjected to extensive characterization studies using sophisticated techniques such as XRD, nitrogen adsorption, HRSEM-EDX, HRTEM and temperature programmed desorption of CO2 (TPD of CO2). The physico-chemical characterization results revealed that these materials possess highly dispersed CaO nanoparticles, excellent nanopores with well-ordered structure, high specific surface area, large specific pore volume, pore diameter and very high basicity. We have also demonstrated that the basicity of the CaO-CMK-3 samples can be controlled by simply varying the amount of CaO loading and pore diameter of the carbon support. The basic catalytic performance of the samples was investigated in the base-catalyzed transesterification of ethylacetoacetate by aryl, aliphatic and cyclic primary alcohols. CMK-3 catalyst with higher CaO loading and larger pore diameter was found to be highly active with higher conversion within a very short reaction time. The activity of 30% CaO-CMK3-150 catalyst for transesterification of ethylacetoacetate using different alcohols increases in the following order: octanol > butanol > cyclohexanol > benzyl alcohol > furfuryl alcohol.     

Improved Cloud Storage Encryption Using Block Cipher-Based DNA Anti-Codify Model

When it comes to data storage, cloud computing and cloud storage providers play a critical role. The cloud data can be accessed from any location with an internet connection. Additionally, the risk of losing privacy when data is stored in a cloud environment is also increased. A variety of security techniques are employed in the cloud to enhance security. In this paper, we aim at maintaining the privacy of stored data in cloud environment by implementing block-based modelling to boost the privacy level with Anti-Codify Technique (ACoT) and block cipher-based algorithms. Initially, the cipher text is generated using Deoxyribo Nucleic Acid (DNA) model. Block-cipher-based encryption is used by ACoT, but the original encrypted file and its extension are broken up into separate blocks. When the original file is broken up into two separate blocks, it raises the security level and makes it more difficult for outsiders to cloud data access. ACoT improves the security and privacy of cloud storage data. Finally, the fuzzy-based classification is used that stores various access types in servers. The simulation results shows that the ACoT-DNA method achieves higher entropy against various block size with reduced computational cost than existing methods.     

A proportional fair scheduling strategy using multiobjective gradient-based African buffalo optimization algorithm for effective resource allocation and interference minimization

The increased usage of Internet of Things (IoT) applications in several areas, like healthcare, agriculture, and business, has aggravated mobile traffic issues to a large extent. The deployment of 5G technology has resulted in increased traffic globally. These coherent devices, on the other hand, use the internet to fine-tune the quality of service in order to provide scalability, anonymity, and accessibility. Despite its numerous virtues, it is bound to encounter issues with interference management, fairness, throughput, and computational complexities. In this paper, a novel Multi-Objective Gradient-based African Buffalo Optimization (MOGABO) algorithm is developed to handle proportional fairness scheduling, improve interference management, increase throughput, and reduce computational complexities in cellular communication systems, particularly device-to-device (D2D) communication. The simulation analysis is done against other approaches such as the Hungarian technique, DDDPG technique, heuristic technique, and SC-FDMA technique demonstrates that this method has improved system fairness over the existing approaches. Our method maximizes throughput, and for 500 UE, the throughput is 10.4 Mbps, with an average queuing delay of 24 ms. As a result, when compared to the existing method, MOGABO method offers a 1.2% increase in throughput. Thus, our method offers better coverage and throughput for D2D cellular communication with the reduction of computational complexities.     

Krempfielins Q and R,Two New Eunicellin-Based Diterpenoids from the Soft Coral Cladiella krempfi

Two new eunicellin-based diterpenoids, krempfielins Q and R (1 and 2), and one known compound cladieunicellin K (3) have been isolated from a Formosan soft coral Cladiella krempfi. The structures of these two new metabolites were elucidated by extensive spectroscopic analysis. Anti-inflammatory activity of new metabolites to inhibit the superoxide anion generation and elastase release in N-formyl-methionyl-leucyl phenylalanine/cytochalasin B (FMLP/CB)-induced human neutrophil cells and cytotoxicity of both new compounds toward five cancer cell lines were reported.     

Temperature dependent damping studies of Ni-Mn-Ga polymer composites

Mechanical properties of ferromagnetic shape memory alloy (FSMA) polyurethane (PU) polymer composites are studied using dynamic mechanical analysis (DMA) at different temperatures. The sample used in the study is Ni-Mn-Ga/PU polymer composite. DMA studies reveal that the mechanical modulus decreases, when the temperature increases. The peak in internal friction (tanδ) appears twice due to martensite transformation of the reinforced particles and glass transition of the polymer matrix. The strain is due to the motion of twin boundaries rather than the phase transformations. Twin boundary motion is found to be the root cause for the martensite-austenite transformation and vice versa, and leads to enhanced damping mechanism. Speculations on twin boundaries of this sample to show concrete evidence on change in internal friction (tanδ) are still underway. This paper proposes that Ni-Mn-Ga/PU polymer composites can be used as efficient dampers.     

The isopropylation of biphenyl over H-mordenite — Roles of 3- and 4-isopropylbiphenyls

The isopropylation of biphenyl (BP) and 3- and 4-isopropylbiphenyls (3- and 4-IPBPs) was examined over H-mordenites (MOR) to elucidate the mechanism of shape-selective formation of 4,4′-diisopropylbiphenyl (4,4′-DIPB). The isopropylation of BP occurred predominantly to form 4-isopropylbiphenyl (4-IPBP) from BP and 4,4′-DIPB from 4-IPBP. However, 3-IPBP, a minor isomer from BP, cannot participate effectively in the formation of 3,4′-DIPB due to steric restriction of its isopropyl moiety with MOR channels. Selective formation of 4,4′-DIPB was observed at low to moderate temperatures: 225–275 °C. However, the selectivities for 4,4′-DIPB were decreased at high temperatures, 300–350 °C under propene pressure, 0.8MPa, by the isomerization of 4,4′-DIPB at external acid sites. The isomerization of 4,4′-DIPB occurred under low propene pressure even at 250 °C. The roles of 3- and 4-IPBPs in the formation of DIPB isomers were examined in the isopropylation of their mixtures. 4-IPBP was consumed much faster than 3-IPBP in all cases examined. 4-IPBP was an exclusive precursor to DIPB isomers, particularly 4,4′-DIPB. 4,4′-DIPB was also found as a predominant isomer in encapsulated products at all conditions examined. These results show that 4-IPBP can preferentially establish active transition state with propene and acid site in MOR channels, resulting in selective formation of 4,4′-DIPB. It is concluded that the isopropylation of BP over MOR occurs through reactant selectivity mechanism and restricted transition state mechanism, but not through product selectivity mechanism.     

A 20 mW 3.24 mm2 Fully Integrated GPS Radio for Location Based Services

The challenges in the co-existence of a GPS receiver with cellular phones for location based services are addressed in this paper. A fully integrated GPS radio, realized in a 0.18 mum SiGe technology, demonstrates a 1 dB gain desensitization at 1.9 GHz of -8 dBm, a noise figure of 5 dB, with 20 mW power consumption. Chip area is 3.24 mm² . The receiver includes a highly selective LNA, key to minimize desensitization and reciprocal mixing due to the large cellphone leakage, a novel quadrature VCO topology capable of directly driving quadrature passive mixer with high swing and low power consumption, complex bandpass filter, variable gain amplifier, automatic gain control, 2-bit quantizer, and a fractional-N sigma-delta-based PLL that can lock to any crystal frequency