41 research outputs found

    Power Quality Improvement Using Series Active Power Filter Based On Gravitational Search Algorithm

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    This paper proposes a heuristic control of the series active power filter for power quality enhancement. In this context, the series active filter is better utilized as a voltage source controller contrary to its conventional usage as variable impedance. The present-day utility system as a linear model is unsatisfactory and the steps are laid down to discuss utility system as a nonlinear model. This paper deals power quality disturbances like voltage sag/swell, voltage error and THD with robust heuristic algorithms like the gravitational search algorithms (GSA) and it is further compared with firefly (FF) algorithm. The harmonic reduction in the source current and mitigation of sags/swells in the load voltage is carried out with optimal tuning of the PI controller. The series active power filter as a harmonic suppressor with a specific reference controlled strategy is discussed in this paper. The synchronous reference frame (SRF) theory is used to generate the reference voltage signals required for compensation. The hysteresis band current controller (HBCC) is used to perform the switching operation of Voltage Source Inverter. Simulations are carried out in the MATLAB/SIMULINK environment

    A comparative study on time efficiency management of self ligating brackets with conventional ligating brackets on orthodontic subjects in North Karnataka

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    Background: Self-Ligating brackets were originally designed with the intention to reduce the time needed to change wires compared with the use of wire ligatures. However, the advent of elastomeric ligatures meant that this perceived advantage was diminished. Objective: To compare aligning efficiency, rate of retraction and torque expression of Self Ligating bracket (SLB) system with Conventional Pre adjusted Edgewise bracket (CLB) system. Materials and Methods: Twelve patients were selected and divided into two groups treated with self ligating brackets (SLB, n=6) and conventional ligating brackets (CLB, n=6). The brackets used were 0.22 slot McLaughlin Bennet Trevesi (MBT) prescription. Aligning was evaluated with 0.14 Niti followed by 19X25 Heat Activated Ni Ti and then 19X25 stainless steel wires for retraction within 4 months. The rate of retraction was evaluated per month and torque loss after space closure was also estimated. Results: Alignment Efficiency shows significant changes with SLB compared to CLB and also save more than 30% of chair side time during wire adjustments while rate of en masse retraction in SLB shows statistically non significance as compared to CLB system. In case of upper incisor changes when compared between two groups showed less torque loss in SLB than CLB although which was statistically no significant but % difference show SLB have better improvement result than CLB

    Markets and marketing research on poverty and its alleviation: Summarizing an evolving logic toward human capabilities, well-being goals and transformation

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    Marketing practitioners and business scholars now view some of the world’s poorest communities as profitable growth markets. Hence a market-based approach to poverty alleviation has gathered momentum. This article traces the evolution of such a market-based approach over four decades and highlights a gradual trend away from a deficit-reduction approach (focused on constraints and justice) towards an opportunity-expansion approach (focused on capabilities and well-being). This trend is summarized in an analytical framework of human capabilities, well-being goals and transformative impact evolved from the literature. The framework is then used to analyse the practice of sanitation marketing, which has emerged as a key method in one of the highest priority domains in international development discourse – sanitation. The article concludes with a discussion of how contemporary work can further take forward the key tenets of the framework and guide the development of ‘good markets’ for the poor

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    A beginning in the reversible logic synthesis of sequential circuits

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    This paper provides the initial threshold to building of more complex system having reversible sequential circuits as a primitive component and which can execute more complicated operations using quantum computers. The reversible circuits form the basic building block of quantum computers as all quantum operations are reversible. The important reversible gates used for reversible logic synthesis are Feynman Gate, New Gate and Fredkin gate. The novelty of the paper is the reversible designs of Flip Flops. The Flip Flops that are synthesized using reversible logic are RS Flip Flop, JK Flip Flop, D Flip Flop, T Flip Flop and Master Slave Flip Flo

    Voltage Reduced Self Refresh (VRSR) for optimized energy savings in DRAM Memories

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    Modern computing systems demand DRAMs with more capacity and bandwidth to keep pace with the onslaught of new data-intensive applications. Though DRAM scaling offers higher density devices to realize high memory capacity systems, energy consumption has become a key design limiter. This is owing to the fact that the memory sub-system continues to be responsible for a significant fraction of overall system energy. Self-refresh mode is one low power state that consumes the least DRAM energy, and this is an essential operation to avoid data loss. However, self-refresh energy also continues to grow with density scaling. This paper carries out a detailed study of reducing self-refresh energy by reducing the supply voltage. PARSEC benchmarks in Gem5 full-system mode are used to quantify the merit of self-refresh energy savings at reduced voltages for normal, reduced, and extended temperature ranges. The latency impacts of basic operations involved in self-refresh operation are evaluated using the 16 nm SPICE model. Possible limitations in extending the work to real hardware are also discussed. As a potential opportunity to motivate for future implementation, DRAM architectural changes, additional low power states and entry/exit flow to exercise reduced voltage operation in self-refresh mode are proposed. We present this new low power mode as Voltage Reduced Self-Refresh (VRSR) operation. Our simulation results show that there is a maximum of ∌12.4% and an average of ∌4% workload energy savings, with less than 0.7% performance loss across all benchmarks, for an aggressive voltage reduction of 150 mV

    Referring Expression Generation in Interaction: A Graph-based perspective

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    An informative and comprehensive overview of the state-of-the-art in natural language generation (NLG) for interactive systems, this guide serves to introduce graduate students and new researchers to the field of natural language processing and artificial intelligence, while inspiring them with ideas for future research. Detailing the techniques and challenges of NLG for interactive applications, it focuses on the research into systems that model collaborativity and uncertainty, are capable of being scaled incrementally, and can engage with the user effectively. A range of real-world case studies is also included. The book and the accompanying website feature a comprehensive bibliography, and refer the reader to corpora, data, software and other resources for pursuing research on natural language generation and interactive systems, including dialog systems, multimodal interfaces and assistive technologies. It is an ideal resource for students and researchers in computational linguistics, natural language processing and related fields. Description of state of the art brings readers up to speed on the techniques and challenges of the field A comprehensive bibliography enables researchers and practitioners to find related work in this area The accompanying website allows researchers and practitioners to find and use data sets and cod
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