Search results for: incubation efficiency
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2551

Search results for: incubation efficiency

1471 Hierarchical Checkpoint Protocol in Data Grids

Authors: Rahma Souli-Jbali, Minyar Sassi Hidri, Rahma Ben Ayed

Abstract:

Grid of computing nodes has emerged as a representative means of connecting distributed computers or resources scattered all over the world for the purpose of computing and distributed storage. Since fault tolerance becomes complex due to the availability of resources in decentralized grid environment, it can be used in connection with replication in data grids. The objective of our work is to present fault tolerance in data grids with data replication-driven model based on clustering. The performance of the protocol is evaluated with Omnet++ simulator. The computational results show the efficiency of our protocol in terms of recovery time and the number of process in rollbacks.

Keywords: Data grids, fault tolerance, chandy-lamport, clustering.

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1470 Fuzzy Based Problem-Solution Data Structureas a Data Oriented Model for ABS Controlling

Authors: Ahmad Habibizad Navin, Mehdi Naghian Fesharaki, Mohamad Teshnelab, Ehsan Shahamatnia

Abstract:

The anti-lock braking systems installed on vehicles for safe and effective braking, are high-order nonlinear and timevariant. Using fuzzy logic controllers increase efficiency of such systems, but impose a high computational complexity as well. The main concept introduced by this paper is reducing computational complexity of fuzzy controllers by deploying problem-solution data structure. Unlike conventional methods that are based on calculations, this approach is based on data oriented modeling.

Keywords: ABS, Fuzzy controller, PSDS, Time-Memory tradeoff, Data oriented modeling.

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1469 A Bi-Objective Model to Address Simultaneous Formulation of Project Scheduling and Material Ordering

Authors: Babak H. Tabrizi, Seyed Farid Ghaderi

Abstract:

Concurrent planning of project scheduling and material ordering has been increasingly addressed within last decades as an approach to improve the project execution costs. Therefore, we have taken the problem into consideration in this paper, aiming to maximize schedules quality robustness, in addition to minimize the relevant costs. In this regard, a bi-objective mathematical model is developed to formulate the problem. Moreover, it is possible to utilize the all-unit discount for materials purchasing. The problem is then solved by the E-constraint method, and the Pareto front is obtained for a variety of robustness values. The applicability and efficiency of the proposed model is tested by different numerical instances, finally.

Keywords: E-constraint method, material ordering, project management, project scheduling.

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1468 A Quantum-Inspired Evolutionary Algorithm forMultiobjective Image Segmentation

Authors: Hichem Talbi, Mohamed Batouche, Amer Draa

Abstract:

In this paper we present a new approach to deal with image segmentation. The fact that a single segmentation result do not generally allow a higher level process to take into account all the elements included in the image has motivated the consideration of image segmentation as a multiobjective optimization problem. The proposed algorithm adopts a split/merge strategy that uses the result of the k-means algorithm as input for a quantum evolutionary algorithm to establish a set of non-dominated solutions. The evaluation is made simultaneously according to two distinct features: intra-region homogeneity and inter-region heterogeneity. The experimentation of the new approach on natural images has proved its efficiency and usefulness.

Keywords: Image segmentation, multiobjective optimization, quantum computing, evolutionary algorithms.

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1467 Optimal Operation of a Photovoltaic Induction Motor Drive Water Pumping System

Authors: Nelson K. Lujara

Abstract:

The performance characteristics of a photovoltaic induction motor drive water pumping system with and without maximum power tracker is analyzed and presented. The analysis is done through determination and assessment of critical loss components in the system using computer aided design (CAD) tools for optimal operation of the system. The results can be used to formulate a well-calibrated computer aided design package of photovoltaic water pumping systems based on the induction motor drive. The results allow the design engineer to pre-determine the flow rate and efficiency of the system to suit particular application.

Keywords: Photovoltaic, water pumping, losses, induction motor.

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1466 Applications of Social Marketing in Road Safety of Georgia

Authors: Charita Jashi

Abstract:

The aim of the paper is to explore the role of social marketing in changing the behavior of consumers on road safety, identify critical aspects and priority needs which impede the implementation of road safety program in Georgia. Given the goals of the study, a quantitative method was used to carry out interviews for primary data collection. This research identified the awareness level of road safety, legislation base, and marketing interventions to change behavior of drivers and pedestrians. During several years the non-governmental sector together with the local authorities and media have been very intensively working on the road safety issue in Georgia, but only seat-belts campaign should be considered rather successful. Despite achievements in this field, efficiency of road safety programs far from fulfillment and needs strong empowering.

Keywords: Road safety, social marketing interventions, behavior change, well-being.

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1465 Development of a Novel Pneumatic Hybrid Engine

Authors: Yu-Ta Shen, Yean-Ren Hwang

Abstract:

Although electrical motors are still the main devices used in vehicular exhaust comprises more than 95 percent of the air pollution in Taiwan's largest city, Taipei. On average, all commuters in Taipei travel 13.6 km daily, while motorcycle commuters travel 12.2 km. The convenience and mobility of motorcycles makes them irreplaceable in Taiwan city traffic but they add significantly to air pollution problems. In order to improve air pollution conditions, some new types of vehicles have been proposed, such as fuel cell driven and hybrid energy vehicles. In this study, we develop a model pneumatic hybrid motorcycle system and simulate its acceleration and mileage (km/L) performance. The results show that the pneumatic hybrid motorcycle can improve efficiency.

Keywords: vehicular, exhaust, air pollution, pneumatic, hybrid, motorcycle

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1464 Miniaturized Wideband Single-Feed Shorted-Edge Stacked Patch Antenna for C-Band Applications

Authors: Abdelheq Boukarkar, Omar Guermoua

Abstract:

In this paper, we propose a miniaturized and wideband patch antenna for C-band applications. The antenna miniaturization is obtained by loading shorting vias along one patch edge. At the same time, the wideband performance is achieved by combining two resonances using one feed line. The measured results reveal that the antenna covers the frequency band 4.32 GHz to 6.52 GHz (41%) with a peak gain and a peak efficiency of 5.5 dBi and 87%, respectively. The antenna occupies a relatively small size of only 26 x 22 x 5.6 mm3, making it suitable for compact wireless devices requiring a stable unidirectional gain over a wide frequency range.

Keywords: Miniaturized antennas, patch antennas, stable gain, wideband antennas.

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1463 Selective Intra Prediction Mode Decision for H.264/AVC Encoders

Authors: Jun Sung Park, Hyo Jung Song

Abstract:

H.264/AVC offers a considerably higher improvement in coding efficiency compared to other compression standards such as MPEG-2, but computational complexity is increased significantly. In this paper, we propose selective mode decision schemes for fast intra prediction mode selection. The objective is to reduce the computational complexity of the H.264/AVC encoder without significant rate-distortion performance degradation. In our proposed schemes, the intra prediction complexity is reduced by limiting the luma and chroma prediction modes using the directional information of the 16×16 prediction mode. Experimental results are presented to show that the proposed schemes reduce the complexity by up to 78% maintaining the similar PSNR quality with about 1.46% bit rate increase in average.

Keywords: Video encoding, H.264, Intra prediction.

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1462 Using Finite Element Method for Determination of Poles Number in Optimal Design of Linear Motor

Authors: Abdolamir Nekoubin

Abstract:

One of Effective parameters on the performance of linear induction motors is number of poles which must be selected and optimized to increase power efficiency and motor performance significantly. In this paper a double-sided linear induction motor with different poles number by using MAXWELL3D software is designed and with finite element method is analyzed electromagnetically. Then for dynamic simulation, linear motor by using MATLAB software is simulated. The results show that by adding poles number, system time response is increased and motor after more time reaches to steady state. Also propulsion force of motor is increased.

Keywords: Linear motor, poles number, finite element method.

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1461 Numerical Analysis for the Performance of a Thermoelectric Generator According to Engine Exhaust Gas Thermal Conditions

Authors: Jinkyu Park, Yungjin Kim, Byungdeok In, Sangki Park, Kihyung Lee

Abstract:

Internal combustion engines rejects 30-40% of the energy supplied by fuel to the environment through exhaust gas. thus, there is a possibility for further significant improvement of efficiency with the utilization of exhaust gas energy and its conversion to mechanical energy or electrical energy. The Thermo-Electric Generator (TEG) will be located in the exhaust system and will make use of an energy flow between the warmer exhaust gas and the external environment. Predict to th optimum position of temperature distribution and the performance of TEG through numerical analysis. The experimental results obtained show that the power output significantly increases with the temperature difference between cold and hot sides of a thermoelectric generator.

Keywords: Thermoelectric generator, Numerical analysis, Seebeck coefficient, Figure of merit

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1460 A Study of Color Transformation on Website Images for the Color Blind

Authors: Siew-Li Ching, Maziani Sabudin

Abstract:

In this paper, we study on color transformation method on website images for the color blind. The most common category of color blindness is red-green color blindness which is viewed as beige color. By transforming the colors of the images, the color blind can improve their color visibility. They can have a better view when browsing through the websites. To transform colors on the website images, we study on two algorithms which are the conversion techniques from RGB color space to HSV color space and self-organizing color transformation. The comparative study focuses on criteria based on the ease of use, quality, accuracy and efficiency. The outcome of the study leads to enhancement of website images to meet the color blinds- vision requirements in perceiving image detailed.

Keywords: Color blind, color transformation, HSV (Hue, Saturation, Value), RGB (Red, Green, Blue).

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1459 Decision Support System for Suppliers

Authors: Babak Tashakori Bafghi, Laleh Tashakori, Reza Allahyari Soeini, Mohammad Mokhtari

Abstract:

Supplier selection is a multi criteria decision-making process that comprises tangible and intangible factors. The majority of previous supplier selection techniques do not consider strategic perspective. Besides, uncertainty is one of the most important obstacles in supplier selection. For the first, time in this paper, the idea of the algorithm " Knapsack " is used to select suppliers Moreover, an attempt has to be made to take the advantage of a simple numerical method for solving model .This is an innovation to resolve any ambiguity in choosing suppliers. This model has been tried in the suppliers selected in a competitive environment and according to all desired standards of quality and quantity to show the efficiency of the model, an industry sample has been uses.

Keywords: Knapsack, linear programming, supplier select, supply chain management.

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1458 Study of Incineration of Acacia Wood Chips for Biomass Power Plant of the Royal Thai Navy in Sattahip, Chonburi Province, Thailand

Authors: Thanapong Suriyea, Teeratas Pornyungyuen, Koonlaya Kanokjaruvijit

Abstract:

This research is aimed to find optimal values of parameters of acacia wood chips combustion in a bubbling fluidized bed for electrification within the area of the Royal Thai Navy in Sattahip, Chonburi province, Thailand. The size of wood chips falls in the range of 25 mm in diameter. The bed temperature is set within the range of 800±10 oC with the air flow rate of 2.1-3.1 m/min corresponding to the air-fuel ratio between 0.71 to 1.03. The resulting thermal efficiency is approximately 95% with a thermal output of 474.76 kWth, which produced the electricity 0.131 kW-hr.

Keywords: Acacia Wood Chips, Biomass, Combustion, Fluidized Bed.

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1457 Slow Pyrolysis of Biowastes: Environmental, Exergetic, and Energetic Assessment

Authors: Daniela Zalazar-Garcia, Erick Torres, Germán Mazza

Abstract:

Slow pyrolysis of a pellet of pistachio waste was studied using a lab-scale stainless-steel reactor. Experiments were conducted at different heating rates (5, 10, and 15 K/min). A 3-E (environmental, exergetic, and energetic) analysis for the processing of 20 kg/h of biowaste was carried out. Experimental results showed that biochar and gas yields decreased with an increase in the heating rate (43% to 36% and 28% to 24%, respectively), while the bio-oil yield increased (29% to 40%). Finally, from the 3-E analysis and the experimental results, it can be suggested that an increase in the heating rate resulted in a higher pyrolysis exergetic efficiency (70%), due to an increase of the bio-oil yield with high-energy content.

Keywords: 3E assessment, biowaste pellet, life cycle assessment, slow pyrolysis.

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1456 How Can We Carry Out Green Incentives Most Efficiently?

Authors: Peter Yang

Abstract:

Green incentives are included in the “American Recovery and Reinvestment Act of 2009" (ARRA). It is, however, unclear how these government incentives can be carried out most effectively according to market-based principles and if they can serve as a catalyst for an accelerated green transformation and an ultimate solution to the current U.S. and global economic and financial crisis. The article will compare the existing U.S. green economic policies with those in Germany, identify problems, and suggest improvements to allow the green stimulus incentives to achieve the best results in the process of an accelerated green transformation. The author argues that the current U.S. green stimulus incentives can only be most successful if they are carried out as part of a visionary, comprehensive, long-term, and consistent strategy of the green economic transformation.

Keywords: Green incentives, financial crisis, green economy, renewable energy sources, energy efficiency.

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1455 Electromagnetic Flow Meter Efficiency

Authors: Andrey D. Andreev, Ilona I. Iatcheva, Dimitar N. Karastoyanov, Rumena D. Stancheva

Abstract:

A study of electromagnetic flow meter is presented in the paper. Comparison has been made between the analytical and the numerical results by the use of FEM numerical analysis (Quick Field 5.6) for determining polarization voltage through the circle cross section of the polarization transducer. Exciting and geometrical parameters increasing its effectiveness has been examined. The aim is to obtain maximal output signal. The investigations include different variants of the magnetic flux density distribution around the tube: homogeneous field of magnitude Bm, linear distribution with maximal value Bm and trapezium distribution conserving the same exciting magnetic energy as the homogeneous field.

Keywords: Effectiveness, electromagnetic flow meter, finite element method, polarization voltage.

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1454 Performance Evaluation of Content Based Image Retrieval Using Indexed Views

Authors: Tahir Iqbal, Mumtaz Ali, Syed Wajahat Kareem, Muhammad Harris

Abstract:

Digital information is expanding in exponential order in our life. Information that is residing online and offline are stored in huge repositories relating to every aspect of our lives. Getting the required information is a task of retrieval systems. Content based image retrieval (CBIR) is a retrieval system that retrieves the required information from repositories on the basis of the contents of the image. Time is a critical factor in retrieval system and using indexed views with CBIR system improves the time efficiency of retrieved results.

Keywords: Content based image retrieval (CBIR), Indexed view, Color, Image retrieval, Cross correlation.

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1453 Rotor Flow Analysis using Animplicit Harmonic Balance Method

Authors: D. Im, S. Choi, H. Kwon, S. H. Park, J. H. Kwon

Abstract:

This paper is an extension of a previous work where a diagonally implicit harmonic balance method was developed and applied to simulate oscillatory motions of pitching airfoil and wing. A more detailed study on the accuracy, convergence, and the efficiency of the method is carried out in the current paperby varying the number of harmonics in the solution approximation. As the main advantage of the method is itsusage for the design optimization of the unsteady problems, its application to more practical case of rotor flow analysis during forward flight is carried out and compared with flight test data and time-accurate computation results.

Keywords: Design optimization, Implicit harmonic balancemethod, number of harmonics, rotor flows

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1452 Ecotoxicity Evaluation and Suggestion of Remediation Method of ZnO Nanoparticles in Aqueous Phase

Authors: Hyunsang Kim, Younghun Kim, Younghee Kim, Sangku Lee

Abstract:

We investigated ecotoxicity and performed experiment for removing ZnO nanoparticles in water. Short term exposure of hatching test using fertilized eggs (O. latipes) showed deformity in 5ppm of ZnO nanoparticles solution. And in 10ppm ZnO nanoparticles solution delayed hatching was observed. Hereine, chemical precipitation method was suggested for removing ZnO nanoparticles in water. The precipitated ZnO nanoparticles showed the form of ZnS after addition of Na2S, and the form of Zn3(PO4)2 for Na2HPO4. The removal efficiency of ZnO nanoparticles in water was closed to 100% for two cases. In ecotoxicity evaluation of as-precipitated ZnS and Zn3(PO4)2, they did not cause any acute toxicity for D. magna. It is noted that this precipitation treatment of ZnO is effective to reduce the potential cytotoxicity.

Keywords: ZnO nanoparticles, ZnS, Zn3(PO4)2, ecotoxicity evaluation, chemical precipitation.

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1451 An Integrated Mixed-Integer Programming Model to Address Concurrent Project Scheduling and Material Ordering

Authors: Babak H. Tabrizi, Seyed Farid Ghaderi

Abstract:

Concurrent planning of project scheduling and material ordering can provide more flexibility to the project scheduling problem, as the project execution costs can be enhanced. Hence, the issue has been taken into account in this paper. To do so, a mixed-integer mathematical model is developed which considers the aforementioned flexibility, in addition to the materials quantity discount and space availability restrictions. Moreover, the activities duration has been treated as decision variables. Finally, the efficiency of the proposed model is tested by different instances. Additionally, the influence of the aforementioned parameters is investigated on the model performance.

Keywords: Material ordering, project scheduling, quantity discount, space availability.

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1450 Wireless Neural Stimulator with Adjustable Electrical Quantity

Authors: Young-Seok Choi

Abstract:

The neural stimulation has been gaining much interest in neuromodulation research and clinical trials. For efficiency, there is a need for variable electrical stimulation such as current and voltage stimuli as well as wireless framework. In this regard, we develop the wireless neural stimulator capable of voltage and current stimuli. The system consists of ZigBee which is a wireless communication module and stimulus generator. The stimulus generator with 8-bits resolution enable both mono-polar and bi-polar waveform in voltage (-3.3~3.3V) and current(-330~330µA) stimulus mode which is controllable. The experimental results suggest that the proposed neural stimulator can play a role as an effective approach for neuromodulation.

Keywords: Neural stimulator, current stimulation, voltage stimulation, neuromodulation

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1449 Restarted GMRES Method Augmented with the Combination of Harmonic Ritz Vectors and Error Approximations

Authors: Qiang Niu, Linzhang Lu

Abstract:

Restarted GMRES methods augmented with approximate eigenvectors are widely used for solving large sparse linear systems. Recently a new scheme of augmenting with error approximations is proposed. The main aim of this paper is to develop a restarted GMRES method augmented with the combination of harmonic Ritz vectors and error approximations. We demonstrate that the resulted combination method can gain the advantages of two approaches: (i) effectively deflate the small eigenvalues in magnitude that may hamper the convergence of the method and (ii) partially recover the global optimality lost due to restarting. The effectiveness and efficiency of the new method are demonstrated through various numerical examples.

Keywords: Arnoldi process, GMRES, Krylov subspace, systems of linear equations.

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1448 Sustainability Strategy and Firm Performance in Residential Trade and Industry: A Conceptual Analysis

Authors: Martin Macion

Abstract:

The request for a sustainable development challenges both managers and consumers to rethink habitual practices and activities. While consumers are challenged to develop sustainable consumption patterns, companies are asked to establish managerial systems and structures considering economical, ecological, and social issues. As this is in particular true for housing associations, this paper aims first, at providing an understanding of sustainability strategy in residential trade and industry (RTI) by identifying relevant facets of this construct and second, at conceptually analyzing the impact of sustainability strategy in RTI on operational efficiency and performance of municipal housing companies. The author develops a model of sustainability strategy in RTI and its effects and further, sheds light in priorities for future research.

Keywords: firm performance, sustainability strategy, residentialtrade and industry

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1447 A Review on the Outlook of the Circular Economy in the Automotive Industry

Authors: A. Buruzs, A. Torma

Abstract:

The relationship of the automotive industry with raw material supply is a major challenge and presents obstacles. Automobiles are ones of the most complex products using a large variety of materials. Safety, eco-friendliness and comfort requirements, physical, chemical and economic limitations set the framework in which this industry continuously optimizes the efficient and responsible use of resources. The concept of circular economy covers the issues of waste generation, resource scarcity and economic advantages. However, circularity is already known for the automobile industry – several efforts are done to foster material reuse, product remanufacturing and recycling. The aim of this study is to give an overview on how the producers comply with the growing demands on one hand, and gain efficiency and increase profitability on the other hand from circular economy.

Keywords: Automotive industry, circular economy, international requirements, natural resources.

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1446 Analysis of Some Solutions to Protect the Tombolo of GIENS

Authors: Yves Lacroix, Van Van Than, Didier Leandri, Pierre Liardet

Abstract:

The tombolo of Giens is located in the town of Hyères (France). We recall the history of coastal erosion, and prominent factors affecting the evolution of the western tombolo. We then discuss the possibility of stabilizing the western tombolo. Our argumentation relies on a coupled model integrating swells, currents, water levels and sediment transport. We present the conclusions of the simulations of various scenarios, including pre-existing propositions from coastal engineering offices. We conclude that beach replenishment seems to be necessary but not sufficient for the stabilization of the beach. Breakwaters reveal effective particularly in the most exposed northern area. Some solutions fulfill conditions so as to be elected as satisfactory. We give a comparative analysis of the efficiency of 14 alternatives for the protection of the tombolo.

Keywords: Breakwaters, coupled models, replenishment, silting.

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1445 JREM: An Approach for Formalising Models in the Requirements Phase with JSON and NoSQL Databases

Authors: Aitana Alonso-Nogueira, Helia Estévez-Fernández, Isaías García

Abstract:

This paper presents an approach to reduce some of its current flaws in the requirements phase inside the software development process. It takes the software requirements of an application, makes a conceptual modeling about it and formalizes it within JSON documents. This formal model is lodged in a NoSQL database which is document-oriented, that is, MongoDB, because of its advantages in flexibility and efficiency. In addition, this paper underlines the contributions of the detailed approach and shows some applications and benefits for the future work in the field of automatic code generation using model-driven engineering tools.

Keywords: Conceptual modeling, JSON, NoSQL databases, requirements engineering, software development.

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1444 Comparison of BER Performances for Conventional and Non-Conventional Mapping Schemes Used in OFDM

Authors: Riddhi Parmar, Shilpi Gupta, Upena Dalal

Abstract:

Orthogonal Frequency Division Multiplexing (OFDM) is one of the techniques for high speed data rate communication with main consideration for 4G and 5G systems. In OFDM, there are several mapping schemes which provide a way of parallel transmission. In this paper, comparisons of mapping schemes used by some standards have been made and also has been discussed about the performance of the non-conventional modulation technique. The Comparisons of Bit Error Rate (BER) performances for conventional and non-conventional modulation schemes have been done using MATLAB software. Mentioned schemes used in OFDM system can be selected on the basis of the requirement of power or spectrum efficiency and BER analysis.

Keywords: BER, π/4 differential quadrature phase shift keying (Pi/4 DQPSK), OFDM, phase shift keying, quadrature phase shift keying.

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1443 Inexact Alternating Direction Method for Variational Inequality Problems with Linear Equality Constraints

Authors: Min Sun, Jing Liu

Abstract:

In this article, a new inexact alternating direction method(ADM) is proposed for solving a class of variational inequality problems. At each iteration, the new method firstly solves the resulting subproblems of ADM approximately to generate an temporal point ˜xk, and then the multiplier yk is updated to get the new iterate yk+1. In order to get xk+1, we adopt a new descent direction which is simple compared with the existing prediction-correction type ADMs. For the inexact ADM, the resulting proximal subproblem has closedform solution when the proximal parameter and inexact term are chosen appropriately. We show the efficiency of the inexact ADM numerically by some preliminary numerical experiments.

Keywords: variational inequality problems, alternating direction method, global convergence

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1442 Nano-Alumina Sulfuric Acid: An Efficient Catalyst for the Synthesis of α-Aminonitriles Derivatives

Authors: Abbas Teimouri, Alireza Najafi Chermahini, Leila Ghorbanian

Abstract:

An efficient and green protocol for the synthesis of α- aminonitriles derivatives by one-pot reaction of different aldehydes with amines and trimethylsilyl cyanides has been developed using natural alumina, alumina sulfuric acid (ASA), nano-γ-alumina, nanoalumina sulfuric acid (nano-ASA) under microwave irradiation and solvent-free conditions. The advantages of methods are short reaction times, high yields, milder conditions and easy work up. The catalysts can be recovered for the subsequent reactions and reused without any appreciable loss of efficiency.

Keywords: Nano-γ-alumina, nano-alumina sulfuric acid, green synthesis, microwave irradiation, α-aminonitriles derivatives.

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