Fast design optimization of UWB antenna with WLAN Band-Notch

In this paper, a methodology for rapid design optimization of an ultra-wideband ( UWB) monopole antenna with a lower WLAN band-notch is presented. The band-notch is realized using an open loop resonator implemented in the radiation patch of the antenna. Design optimization is a two stage process, with the first stage focused on the design of the antenna itself, and the second stage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. Both optimization stages are realized using surrogate-based optimization involving variable-fidelity electromagnetic ( EM) simulation models as well as an additive response correction ( first stage), and sequential approximate optimization ( second stage). The final antenna design is obtained at the CPU cost corresponding to only 23 high-fidelity EM antenna simulations

Cultural Records shown by the songs of Perunkadungo

Culture is capable of giving humanity greatness, welfare, and specific identities. Cultural elements take the lead in the construction of individual superiority and social improvements. Literature plays a significant role in the factors that reveal the cultural environment of a society. In this way, the Sangam literary texts are of great help in understanding the cultural milieu of the Sangam era. The great poets of the Sangam age recorded in their poems the cultural aspects of the people who lived at that time. The cultures of the Sangam era can be called the Thinai culture and the Ainthinai culture. Perunkadungo is one of the great poets of the Sangam age. He belonged to Kongu Nadu, one of the ancient kingdoms of Tamil Nadu. He is good at singing Paalai Thinai songs. Therefore, he is called Perunkadugo, who sang paalai. He has revealed the cultural aspects of the period through the Agathinai people in his songs. The purpose of this paper is to project them

Impact of Fii in recent stock market volatility / D. S. Selvakumar

The growth of relationship of interdependence between individuals and institutions across geographical and political boundaries through globalisation leads to increase of flow of investments capital. Globalisation refers to a process of increasing economic integration and growing economic interdependence between countries in the world economy. For a developing country, opening up of the stock market to FII can act as catalyst in improving efficiency of the market. As FII arrival is associated with the importation of sophisticated financial technology, adoption of the technology to the domestic environment, and greater investments in improving information processing and financial services. However these benefits should be weighted against uncertainties associated with opening up of the market. One of the major concerns is that the portfolio funds may lead to greater volatility in domestic stock prices. If foreign stock prices for any reason fluctuate the domestic prices will also respond to the fluctuations. This paper focuses on the impact of FIIs in the stock market volatility in recent times

2D-ACAR Studies on Swift Heavy Ion Si-Implanted GaAs

AbstractMaterial properties modification by high energy heavy ion implantation is a prospective technology leading to many device fabrications. This technique induces defects and hence the physical properties of the materials are modified. The effects of swift heavy ion implantation induced defects by 120 MeV 28+Si ion implantation and doping in SI-GaAs are presented from the electron momentum distribution (EMD) of vacancy-type defects studied by two-dimensional angular correlation of annihilation radiation (2D-ACAR). The positron trapping due to the influence of high-energy Si- implantation in GaAs (n-type) is compared with the corresponding spectra of SI- GaAs and with Si-doped (n-type) GaAs. The EMD of the implanted sample shows a distinct increased isotropic distribution with a characteristic transform of its structure as evident from the low momentum region compared to the pristine sample. The characteristics of defects created by Si doping and by 120 MeV 28+Si ion implantation of undoped semi-insulating (SI) GaAS are discussed. These results indicate the nature of positron trapping in open volume defects such as vacancy clusters created by implantation

Evolution of a Hybrid Model for an Effective Perimeter Security Device

Clustering and classification models, or hybrid models are the most widely used models that can handle the diverse nature of NIDS dataset. Dirichlet process clustering technique is a non-parametric Bayesian mixture model that considers the data distribution of the dataset for the formation of distinct clusters. The number of clusters is not known a priori and it differs across different datasets. Determining the number of clusters based on the distribution of data instances can increase the performance of the model. Naive Bayes model, a supervised learning classification technique, maintains a better computational efficiency, by reducing the training time. In this paper, we propose a hybrid model to exploit the positive aspect of proper clustering of data instances and the computational efficiency in building a NIDS. RIPPER algorithm is used to extract rules from the traffic description for updation of the rule database. Experiments were conducted in the KDD CUP’99 and SSENet-2011 datasets to study the performance of the proposed model. Also, a comparison of three hybrid methods with the proposed hybrid model was carried out. The results showed that the proposed hybrid model is superior in building a robust perimeter security device

SERVICE LIFE PREDICTION FOR CONCRETE COMPOSITE WITH CARBON FIBRES FOR MARINE ENVIRONMENT

As construction technologies are improved and as we go for advanced technologies in construction of infrastructure facilities the importance of concrete technology is also more demanding. The field of concrete technology has many new admixtures which improves the properties of concrete. Durability and performance of structures are the main focus now. In view of this, apart from just proportioning a concrete mix, researchers are now interested in testing the performance of the material in varied environmental conditions. Service life prediction is the evaluation of the performance of the structure over a period of time. The prediction involves knowledge of materials science, laboratory testing and data from structures that are in service. It is a complex area where interpretation of correct data has been used and it involves systematic approaches. Researchers have used numerous methodologies and mathematical formulae that are used for the service life prediction. Accelerated laboratory tests forms the basis for these kinds of predictions. This paper deals with proportioning of concrete composite that can be used in aggressive marine environment, subject to severe exposure and the service life prediction of the material in such environment. Admixtures play a major role in making concrete durable. This paper discusses the properties of concrete composite that has been customized with silica fume, fly ash and copper slag for improving the strength of concrete. Carbon fibres have been added to resist the impact of sea waves and also to improve the flexural toughness of concrete. As there are various factors that have been considered in proportioning this particular concrete mix, experimental trials have been designed with reference to central composite design of Response Surface methodology using Design Expert software. The trials were cast using these design mixes and tests were conducted for strength properties and durability parameters. The experimental results have been analyzed for ANOVA to test the accuracy of results. Multiple optimizations have been done to get the best mix with maximum strength and minimum durability issues

GC-MS ANALYSIS OF BIOACTIVE CONSTITUENTS OF METHANOLIC EXTRACT OF LEAVES OF ACTINODAPHNE BOURDILLONII GAMBLE

Objective: The investigation was carried out to characterize the chemical constituents present in the methanolic extracts of leaves of Actinodaphne bourdillonii Gamble using GC-MS. Methods: The chemical constituents of methanolic extract of A. bourdillonii were studied by using Perkin Elmer Gas Chromatography- Mass Spectroscopy. Results: The GC-MS analysis of the methanolic extract revealed the presence of 18 compounds. The major chemical constituents are Tobacco compounds- 4,8,13-Cyclotetradecatriene-1,3-diol, 1,5,9-trimethyl-12-(1-methylethyl)- (33.47%), Terpene alcohol compounds - 3,7,11,15-Tetramethyl-2-hexadecen-1-ol (10.78%), Myirstic acid - Tetradecanoic acid (9.89%) and Sugar moiety compounds -1,6-Anhydro-2,4-dideoxy-á-D-ribo-hexopyranose (7.93%). The analysis of bioactive principles of methanolic extract of leaves of A. bourdillonii has not been reported previously. Conclusion: A. bourdillonii is a valuable tree with numerous medicinal properties which contains various bioactive principles. Such studies will be very much help full in designing a new drugs for the therapeutic values