• Journal of Electrical Engineering and Technology
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• v.10 no.6
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• pp.2406-2412
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• 2015

Multi-user multi-input multi-output (MU-MIMO) system has attracted the 4^th generation wireless network as one of core technique for performance enrichment. In this system rate control is a challenging problem and another problem is optimization. Proper scheduling can resolve these problems by deciding which set of user and at which rate the users send their data. This paper proposes a new multi-parameter based scheduling (MPS) for downlink multi-user multiple-input multiple-output (MU-MIMO) system under space-time block coding (STBC) transmissions. Goal of this MPS scheme is to offer improved link level performance in terms of a low average bit error rate (BER), high packet delivery ratio (PDR) with improved resource utilization and service fairness among the user. This scheme allows the set of users to send data based on their channel quality and their demand rates. Simulation compares the MPS performance with other scheduling scheme such as fair scheduling (FS), normalized priority scheduling (NPS) and threshold based fair scheduling (TFS). The results obtained prove that MPS has significant improvement in average BER performance with improved resource utilization and fairness as compared to the other scheduling scheme.

• Journal of Crop Science and Biotechnology
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• v.11 no.1
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• pp.63-68
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• 2008

The induced genetic divergence was estimated in 44 mutant lines of finger millet variety GPU 26, developed by single and combination treatments with gamma rays, EMS and NG using three multivariate analyses. The mutant lines were grouped into eight genetically diverse clusters by multivariate D2 and canonical analyses and 11 clusters by dendrogram grouping through Gower's similarity coefficient. The clustering pattern in these three methods was almost similar. Twelve mutant lines in D2 and 13 in the dendrogram grouping method were grouped in the parental cluster(Cluster I) indicating that they did not possess enough divergence from the parent to be classified as micromutant lines. However a large proportion of mutant lines showed divergence from the parent variety and also among themselves. No definite relationship of mutagenic origin and clustering of mutant lines were observed. The mutant lines developed from the same mutagenic treatments often grouped into different clusters indicating that each mutagenic treatment was effective in inducing diverse types of changes in the nine traits studied. The hybridization program between the divergent mutant lines GE 2-2 or GE 3-4 with GG 3-1 is expected to give promising and desirable segregants in subsequent generations. Traits such as days to 50% flowering and days to maturity had major contributions to the induced genetic divergence.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.1978-1987
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• 2014

Power requirement to the induction heating system varies during the heating process. A closed loop control is required to have a smooth control over the power. In this work, a constant frequency pulse density modulation based power tracking control scheme for domestic induction heating system is developed using the Fuzzy Logic Controller. In the conventional power modulation schemes, the switching losses increase with the change in the load. The proposed pulse density modulation scheme maintains minimum switching losses for the entire load range. This scheme is implemented for the class-D series resonant inverter system. Fuzzy logic controller based power tracking control scheme is developed for domestic induction heating power supply for various power settings. The open loop and closed loop simulation studies are done using the MATLAB/Simulink simulation tool. The control logic is implemented in hardware using the PIC16F877A microcontroller. Fuzzy controller tracks the set power by changing the pulse density of the gate pulses applied to the inverter. The results obtained are used to know the effectiveness of the fuzzy logic controller to achieve the set power.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1821-1834
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• 2017

Medium voltage control applications due to obtain better output voltage and reduced electro-magnetic interference multi level inverter is used. In closed loop control with inverter, the PI controller does not operate satisfactorily when the operating point changes. This paper presents the performance of Co-Efficient diagram PI controller based indirect vector controlled induction motor drive fed from three-level inverter under different operating conditions (dynamic and steady state). The proposed Co-Efficient diagram PI controller based three level inverter significantly reduces the torque ripple compared to that of conventional PI controller. The performance of the indirect vector controlled induction motor drive has been simulated at different operating conditions. For three-level inverter control, a simplified space vector modulation technique is implemented, which reduces the coordinate transformations complications in the algorithms. The performance parameters, torque ripple contents and THD of induction motor drive with three-level inverter is compared under different operating conditions using CDM-PI and conventional PI controllers.

• Structural Engineering and Mechanics
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• v.19 no.1
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• pp.97-106
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• 2005

The standard practice is to seismically qualify the safety related equipment and structural components used in the nuclear power plants. Among several qualification approaches the qualification by the analysis using finite element (FE) method is the most common approach used in practice. However the predictions by the FE model for a structure is known to show significant deviations from the dynamic behaviour of 'as installed' structure in many cases. Considering such limitation, few researchers have advocated re-qualification of such structures after installation at site to enhance the confidence in qualification vis-$\grave{a}$-vis plant safety. For such an exercise the validation of FE model with experimental modal data is important. A validated FE model can be obtained by the Model Updating methods in conjugation with the in-situ experimental modal data. Such a model can then be used for qualification. Seismic analysis using the updated FE model and its advantage has been presented through an example of an in-core component - a perforated horizontal tube of a nuclear reactor.

• Structural Engineering and Mechanics
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• v.25 no.2
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• pp.239-268
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• 2007

This paper deals with optimal stacking sequence design of laminate composite structures. The stacking sequence optimisation of laminate composites is formulated as a combinatorial problem and is solved using Simulated Annealing (SA), an algorithm devised based on inspiration of physical process of annealing of solids. The combinatorial constraints are handled using a correction strategy. The SA algorithm is strengthened by embedding Tabu search in order to prevent recycling of recently visited solutions and the resulting algorithm is referred to as tabu embedded simulated Annealing (TSA) algorithm. Computational performance of the proposed TSA algorithm is enhanced through cache-fetch implementation. Numerical experiments have been conducted by considering rectangular composite panels and composite cylindrical shell with different ply numbers and orientations. Numerical studies indicate that the TSA algorithm is quite effective in providing practical designs for lay-up sequence optimisation of laminate composites. The effect of various neighbourhood search algorithms on the convergence characteristics of TSA algorithm is investigated. The sensitiveness of the proposed optimisation algorithm for various parameter settings in simulated annealing is explored through parametric studies. Later, the TSA algorithm is employed for multi-criteria optimisation of hybrid composite cylinders for simultaneously optimising cost as well as weight with constraint on buckling load. The two objectives are initially considered individually and later collectively to solve as a multi-criteria optimisation problem. Finally, the computational efficiency of the TSA based stacking sequence optimisation algorithm has been compared with the genetic algorithm and found to be superior in performance.

• Structural Engineering and Mechanics
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• v.64 no.1
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• pp.59-69
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• 2017

The field of fracture mechanics has gained significance because of its ability to address the behaviour of cracks. Predicting the fracture properties of concrete based on experimental investigations is a challenge considering the quasi-brittle nature of concrete. So, there is a need for developing a standard numerical tool which predicts the fracture energy of concrete which is at par with experimental results. The present study is an attempt to evaluate the fracture energy and characteristic length for different grades of concrete using Concrete Damage Plasticity (CDP) model. Indian Standard and EUROCODE are used for the basic input parameters of concrete. Numerical evaluation is done using Finite Element Analysis Software ABAQUS/CAE. Hsu & Hsu and Saenz stress-strain models are adopted for the current study. Mesh sensitivity analysis is also carried to study the influence of type and size of elements on the overall accuracy of the solution. Different input parameters like dilatation angle, eccentricity are varied and their effect on fracture properties is addressed. The results indicated that the fracture properties of concrete for various grades can be accurately predicted without laboratory tests using CDP model.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2829-2832
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• 2012

Background: This study aimed to research the awareness of screening colonoscopy (SC) among patients with colorectal cancer (CRC) and their relatives. Methodology: A questionnaire form including information and behavior about colonoscopic screening for CRCs of patients and their first-degree relatives (FDRs) was prepared. Results: A total of 406 CRC patients were enrolled into the study, with 1534 FDRs (siblings n: 1381 and parents n: 153). Positive family history for CRC was found in 12% of the study population. Previous SC was performed in 11% of patients with CRC. Mean age of the patients whose FDRs underwent SC was lower than the patients whose FDRs did not (52 vs 57 years; p<0,001). The frequency of SC in FDRs was 64% in patients diagnosed CRC under 35 years of age. Persons having a positive family history of CRC had SC more often (51 vs 22%, p<0,001). FDRs of patients having a higher educational level and income had SC more frequently. Conclusions: When screening for CRC is planned, elderly subjects, those with family history for CRC, and those with low educational and lower income should be given esspecial attention in order that they be convinced to undergo screening for CRC.

• Animal cells and systems
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• v.11 no.2
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• pp.161-164
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• 2007

Oxidative stress is prerequisite for the development of atherosclerosis. Apart from the traditional risk factors that contribute to this devastating condition, in the past few decades, much attention has been focused on plasma total homocysteine mainly because of its strong association with coronary artery disease. It has been suggested that homocysteine induces oxidative stress and hence the present work was undertaken to assess the total homocysteine status and plasma total antioxidant capacity in the acute myocardial infarction (AMI) patients among Tamil population. The study subjects included only the Tamil population. Blood samples were collected from 100 AMI patients and 100 controls. Plasma was separated and the total antioxidant status was assessed as a measure of ferric reducing power of antioxidants using spectrophotometric method. Plasma total homocysteine concentrations were assessed by automated chemiluminescence method. While Total antioxidant status was significantly decreased, the plasma homocysteine concentrations were elevated in AMI patients compared to the controls. However, there was no correlation between the homocysteine levels and total antioxidant status. The findings of this study may have therapeutic implications, including food sources rich in antioxidants for all AMI patients to minimize the effect of free radicals formed during oxidative stress among Tamil population.

• BMB Reports
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• v.41 no.4
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• pp.338-343
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• 2008

Dehydrins (DHNs) compose a family of intrinsically unstructured proteins that have high water solubility and accumulate during late seed development at low temperature or in water-deficit conditions. They are believed to play a protective role in freezing and drought-tolerance in plants. A full-length cDNA encoding DHN (designated as ClDhn) was isolated from an oriental medicinal plant Codonopsis lanceolata, which has been used widely in Asia for its anticancer and anti-inflammatory properties. The full-length cDNA of ClDhn was 813 bp and contained a 477 bp open reading frame (ORF) encoding a polypeptide of 159 amino acids. Deduced ClDhn protein had high similarities with other plant DHNs. RT-PCR analysis showed that different abiotic stresses such as salt, wounding, chilling and light, triggered a significant induction of ClDhn at different time points within 4-48 hrs post-treatment. This study revealed that ClDhn assisted C. lanceolata in becoming resistant to dehydration.