Search results for: output response
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2623

Search results for: output response

2293 Optimization of PEM Fuel Cell Biphasic Model

Authors: Boubekeur Dokkar, Nasreddine Chennouf, Noureddine Settou, Belkhir Negrou, Abdesslam Benmhidi

Abstract:

The optimal operation of proton exchange membrane fuel cell (PEMFC) requires good water management which is presented under two forms vapor and liquid. Moreover, fuel cells have to reach higher output require integration of some accessories which need electrical power. In order to analyze fuel cells operation and different species transport phenomena a biphasic mathematical model is presented by governing equations set. The numerical solution of these conservation equations is calculated by Matlab program. A multi-criteria optimization with weighting between two opposite objectives is used to determine the compromise solutions between maximum output and minimal stack size. The obtained results are in good agreement with available literature data.

Keywords: Biphasic model, PEM fuel cell, optimization, simulation, specie transport.

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2292 Financial Regulations in the Process of Global Financial Crisis and Macroeconomics Impact of Basel III

Authors: M. Okan Tasar

Abstract:

Basel III (or the Third Basel Accord) is a global regulatory standard on bank capital adequacy, stress testing and market liquidity risk agreed upon by the members of the Basel Committee on Banking Supervision in 2010-2011, and scheduled to be introduced from 2013 until 2018. Basel III is a comprehensive set of reform measures. These measures aim to; (1) improve the banking sector-s ability to absorb shocks arising from financial and economic stress, whatever the source, (2) improve risk management and governance, (3) strengthen banks- transparency and disclosures. Similarly the reform target; (1) bank level or micro-prudential, regulation, which will help raise the resilience of individual banking institutions to periods of stress. (2) Macro-prudential regulations, system wide risk that can build up across the banking sector as well as the pro-cyclical implication of these risks over time. These two approaches to supervision are complementary as greater resilience at the individual bank level reduces the risk system wide shocks. Macroeconomic impact of Basel III; OECD estimates that the medium-term impact of Basel III implementation on GDP growth is in the range -0,05 percent to -0,15 percent per year. On the other hand economic output is mainly affected by an increase in bank lending spreads as banks pass a rise in banking funding costs, due to higher capital requirements, to their customers. Consequently the estimated effects on GDP growth assume no active response from monetary policy. Basel III impact on economic output could be offset by a reduction (or delayed increase) in monetary policy rates by about 30 to 80 basis points. The aim of this paper is to create a framework based on the recent regulations in order to prevent financial crises. Thus the need to overcome the global financial crisis will contribute to financial crises that may occur in the future periods. In the first part of the paper, the effects of the global crisis on the banking system examine the concept of financial regulations. In the second part; especially in the financial regulations and Basel III are analyzed. The last section in this paper explored the possible consequences of the macroeconomic impacts of Basel III.

Keywords: Banking Systems, Basel III, Financial regulation, Global Financial Crisis.

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2291 A Performance Appraisal of Neural Networks Developed for Response Prediction across Heterogeneous Domains

Authors: H. Soleimanjahi, M. J. Nategh, S. Falahi

Abstract:

Deciding the numerous parameters involved in designing a competent artificial neural network is a complicated task. The existence of several options for selecting an appropriate architecture for neural network adds to this complexity, especially when different applications of heterogeneous natures are concerned. Two completely different applications in engineering and medical science were selected in the present study including prediction of workpiece's surface roughness in ultrasonic-vibration assisted turning and papilloma viruses oncogenicity. Several neural network architectures with different parameters were developed for each application and the results were compared. It was illustrated in this paper that some applications such as the first one mentioned above are apt to be modeled by a single network with sufficient accuracy, whereas others such as the second application can be best modeled by different expert networks for different ranges of output. Development of knowledge about the essentials of neural networks for different applications is regarded as the cornerstone of multidisciplinary network design programs to be developed as a means of reducing inconsistencies and the burden of the user intervention.

Keywords: Artificial Neural Network, Malignancy Diagnosis, Papilloma Viruses Oncogenicity, Surface Roughness, UltrasonicVibration-Assisted Turning.

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2290 Subarray Based Multiuser Massive MIMO Design Adopting Large Transmit and Receive Arrays

Authors: Tetsuki Taniguchi, Yoshio Karasawa

Abstract:

This paper describes a subarray based low computational design method of multiuser massive multiple input multiple output (MIMO) system. In our previous works, use of large array is assumed only in transmitter, but this study considers the case both of transmitter and receiver sides are equipped with large array antennas. For this aim, receive arrays are also divided into several subarrays, and the former proposed method is modified for the synthesis of a large array from subarrays in both ends. Through computer simulations, it is verified that the performance of the proposed method is degraded compared with the original approach, but it can achieve the improvement in the aspect of complexity, namely, significant reduction of the computational load to the practical level.

Keywords: Massive multiple input multiple output (MIMO), multiuser, large array, subarray, zero forcing, singular value decomposition.

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2289 Nanocrystalline Na0.1V2O5.nH2O Xerogel Thin Film for Gas Sensing

Authors: M. S. Al-Assiri, M. M. El-Desoky, Ahmed A. Ibrahim, M. Abaker, A. A. Bahgat

Abstract:

Nanocrystalline thin film of Na0.1V2O5.nH2O xerogel obtained by sol gel synthesis was used as gas sensor. Gas sensing properties of different gases such as hydrogen, petroleum and humidity were investigated. Applying XRD and TEM the size of the nanocrystals is found to be 7.5 nm. SEM shows a highly porous structure with submicron meter-sized voids present throughout the sample. FTIR measurement shows different chemical groups identifying the obtained series of gels. The sample was n-type semiconductor according to the thermoelectric power and electrical conductivity. It can be seen that the sensor response curves from 130oC to 150oC show a rapid increase in sensitivity for all types of gas injection, low response values for heating period and the rapid high response values for cooling period. This result may suggest that this material is able to act as gas sensor during the heating and cooling process.

Keywords: Sol gel, Thermoelectric power, XRD, TEM, Gas sensing.

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2288 Hypertensive Response to Maximal Exercise Test in Young and Middle Age Hypertensive on Blood Pressure Lowering Medication: Monotherapy vs. Combination Therapy

Authors: James Patrick A. Diaz, Raul E. Ramboyong

Abstract:

Background: Hypertensive response during maximal exercise test provides important information on the level of blood pressure control and evaluation of treatment. Method: A single center retrospective descriptive study was conducted among 117 young (aged 20 to 40) and middle age (aged 40 to 65) hypertensive patients, who underwent treadmill stress test. Currently on maintenance frontline medication either monotherapy (Angiotensin-converting enzyme inhibitor/Angiotensin receptor blocker [ACEi/ARB], Calcium channel blocker [CCB], Diuretic - Hydrochlorthiazide [HCTZ]) or combination therapy (ARB+CCB, ARB+HCTZ), who attained a maximal exercise on treadmill stress test (TMST) with hypertensive response (systolic blood pressure: male >210 mm Hg, female >190 mm Hg, diastolic blood pressure >100 mmHg, or increase of >10 mm Hg at any time during the test), on Bruce and Modified Bruce protocol. Exaggerated blood pressure response during exercise (systolic [SBP] and diastolic [DBP]), peak exercise blood pressure (SBP and DBP), recovery period (SBP and DBP) and test for ischemia and their antihypertensive medication/s were investigated. Analysis of variance and chi-square test were used for statistical analysis. Results: Hypertensive responses on maximal exercise test were seen mostly among female population (P < 0.000) and middle age (P < 0.000) patients. Exaggerated diastolic blood pressure responses were significantly lower in patients who were taking CCB (P < 0.004). A longer recovery period that showed a delayed decline in SBP was observed in patients taking ARB+HCTZ (P < 0.036). There were no significant differences in the level of exaggerated systolic blood pressure response and during peak exercise (both systolic and diastolic) in patients using either monotherapy or combination antihypertensives. Conclusion: Calcium channel blockers provided lower exaggerated diastolic BP response during maximal exercise test in hypertensive middle age patients. Patients on combination therapy using ARB+HCTZ exhibited a longer recovery period of systolic blood pressure.

Keywords: Antihypertensive, exercise test, hypertension, hypertensive response.

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2287 Analysis and Performance Evaluation of Noise-Reduction Transformer

Authors: Toshiaki Yanada, Kazumi Ishikawa

Abstract:

The present paper deals with the analysis and development of noise-reduction transformer that has a filter function for conductive noise transmission. Two types of prototype noise-reduction transformers with two different output voltages are proposed. To determine an optimum design for the noise-reduction transformer, noise attenuation characteristics are discussed based on the experiments and the equivalent circuit analysis. The analysis gives a relation between the circuit parameters and the noise attenuation. High performance step-down noise-reduction transformer for direct power supply to electronics equipment is developed. The input voltage of the transformer is 100 V and the output voltage is 5 V. Frequency characteristics of noise attenuation are discussed, and prevention of pulse noise transmission is demonstrated. Normal mode noise attenuation of this transformer is –80 dB, and common mode exceeds –90 dB. The step-down noise-reduction transformer eliminates pulse noise efficiently.

Keywords: conductive noise, EMC, EMI, noise attenuation, transformer.

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2286 Modeling of Bisphenol A (BPA) Removal from Aqueous Solutions by Adsorption Using Response Surface Methodology (RSM)

Authors: Mohammad Ali Zazouli, Farzaneh Veisi, Amir Veisi

Abstract:

Bisphenol A (BPA) is an organic synthetic compound that has many applications in various industries and is known as persistent pollutant. The aim of this research was to evaluate the efficiency of bone ash and banana peel as adsorbents for BPA adsorption from aqueous solution by using Response Surface Methodology. The effects of some variables such as sorbent dose, detention time, solution pH, and BPA concentration on the sorption efficiency was examined. All analyses were carried out according to Standard Methods. The sample size was performed using Box-Benken design and also optimization of BPA removal was done using response surface methodology (RSM). The results showed that the BPA adsorption increases with increasing of contact time and BPA concentration. However, it decreases with higher pH. More adsorption efficiency of a banana peel is very smaller than a bone ash so that BPA removal for bone ash and banana peel is 62 and 28 percent, respectively. It is concluded that a bone ash has a good ability for the BPA adsorption.

Keywords: Adsorbent, banana peel, bisphenol A (BPA), bone ash, wastewater treatment.

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2285 Optimization of Lipase Production Using Bacillus subtilis by Response Surface Methodology

Authors: A. Shyamala Devi, K. Chitra Devi, R. Rajendiran

Abstract:

A total of 6 isolates of Bacillus subtilis were isolated from oil mill waste collected in Namakkal district, Tamilnadu, India. The isolated bacteria were screened using lipase screening medium containing Tween 80. BS-3 isolate exhibited a greater clear zone than the others, indicating higher lipase activity. Therefore, this isolate was selected for media optimization studies. Ten process variables were screened using Plackett–Burman design and were further optimized by central composite design of response surface methodology for lipase production in submerged fermentation. Maximum lipase production of 16.627 U/min/ml were predicted in medium containing yeast extract (9.3636g), CaCl2 (0.8986g) and incubation periods (1.813 days). A mean value of 16.98 ± 0.2286 U/min/ml of lipase was acquired from real experiments.

Keywords: Bacillus subtilis, extracellular lipase, Plackett–Burman design, response surface methodology.

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2284 High Performance In0.42Ga0.58As/In0.26Ga0.74As Vertical Cavity Surface Emitting Quantum Well Laser on In0.31Ga0.69As Ternary Substrate

Authors: Md. M. Biswas, Md. M. Hossain, Shaikh Nuruddin

Abstract:

This paper reports on the theoretical performance analysis of the 1.3 μm In0.42Ga0.58As /In0.26Ga0.74As multiple quantum well (MQW) vertical cavity surface emitting laser (VCSEL) on the ternary In0.31Ga0.69As substrate. The output power of 2.2 mW has been obtained at room temperature for 7.5 mA injection current. The material gain has been estimated to be ~3156 cm-1 at room temperature with the injection carrier concentration of 2×1017 cm-3. The modulation bandwidth of this laser is measured to be 9.34 GHz at room temperature for the biasing current of 2 mA above the threshold value. The outcomes reveal that the proposed InGaAsbased MQW laser is the promising one for optical communication system.

Keywords: Quantum well, VCSEL, output power, materialgain, modulation bandwidth.

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2283 Development and Validation of the Response to Stressful Situations Scale in the General Population

Authors: C. Barreto Carvalho, C. da Motta, M. Sousa, J. Cabral, A. L. Carvalho, E. B. Peixoto

Abstract:

The aim of the current study was to develop and validate a Response to Stressful Situations Scale (RSSS) for the Portuguese population. This scale assesses the degree of stress experienced in scenarios that can constitute positive, negative and more neutral stressors, and also describes the physiological, emotional and behavioral reactions to those events according to their intensity. These scenarios include typical stressor scenarios relevant to patients with schizophrenia, which are currently absent from most scales, assessing specific risks that these stressors may bring on subjects, which may prove useful in non-clinical and clinical populations (i.e. Patients with mood or anxiety disorders, schizophrenia). Results from Principal Components Analysis and Confirmatory Factor Analysis of two adult samples from general population allowed to confirm a three-factor model with good fit indices: χ2 (144)= 370.211, p = 0.000; GFI = 0.928; CFI = 0.927; TLI = 0.914, RMSEA = 0.055, P(rmsea ≤0.005) = .096; PCFI = .781. Further data analysis of the scale revealed that RSSS is an adequate assessment tool of stress response in adults to be used in further research and clinical settings, with good psychometric characteristics, adequate divergent and convergent validity, good temporal stability and high internal consistency.

Keywords: Assessment, stress events, stress response, stress vulnerability.

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2282 Data Envelopment Analysis under Uncertainty and Risk

Authors: P. Beraldi, M. E. Bruni

Abstract:

Data Envelopment Analysis (DEA) is one of the most widely used technique for evaluating the relative efficiency of a set of homogeneous decision making units. Traditionally, it assumes that input and output variables are known in advance, ignoring the critical issue of data uncertainty. In this paper, we deal with the problem of efficiency evaluation under uncertain conditions by adopting the general framework of the stochastic programming. We assume that output parameters are represented by discretely distributed random variables and we propose two different models defined according to a neutral and risk-averse perspective. The models have been validated by considering a real case study concerning the evaluation of the technical efficiency of a sample of individual firms operating in the Italian leather manufacturing industry. Our findings show the validity of the proposed approach as ex-ante evaluation technique by providing the decision maker with useful insights depending on his risk aversion degree.

Keywords: DEA, Stochastic Programming, Ex-ante evaluation technique, Conditional Value at Risk.

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2281 Effect of Size of the Step in the Response Surface Methodology using Nonlinear Test Functions

Authors: Jesús Everardo Olguín Tiznado, Rafael García Martínez, Claudia Camargo Wilson, Juan Andrés López Barreras, Everardo Inzunza González, Javier Ordorica Villalvazo

Abstract:

The response surface methodology (RSM) is a collection of mathematical and statistical techniques useful in the modeling and analysis of problems in which the dependent variable receives the influence of several independent variables, in order to determine which are the conditions under which should operate these variables to optimize a production process. The RSM estimated a regression model of first order, and sets the search direction using the method of maximum / minimum slope up / down MMS U/D. However, this method selects the step size intuitively, which can affect the efficiency of the RSM. This paper assesses how the step size affects the efficiency of this methodology. The numerical examples are carried out through Monte Carlo experiments, evaluating three response variables: efficiency gain function, the optimum distance and the number of iterations. The results in the simulation experiments showed that in response variables efficiency and gain function at the optimum distance were not affected by the step size, while the number of iterations is found that the efficiency if it is affected by the size of the step and function type of test used.

Keywords: RSM, dependent variable, independent variables, efficiency, simulation

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2280 Design, Simulation and Experimental Realization of Nonlinear Controller for GSC of DFIG System

Authors: R.K. Behera, S.Behera

Abstract:

In a wind power generator using doubly fed induction generator (DFIG), the three-phase pulse width modulation (PWM) voltage source converter (VSC) is used as grid side converter (GSC) and rotor side converter (RSC). The standard linear control laws proposed for GSC provides not only instablity against comparatively large-signal disturbances, but also the problem of stability due to uncertainty of load and variations in parameters. In this paper, a nonlinear controller is designed for grid side converter (GSC) of a DFIG for wind power application. The nonlinear controller is designed based on the input-output feedback linearization control method. The resulting closed-loop system ensures a sufficient stability region, make robust to variations in circuit parameters and also exhibits good transient response. Computer simulations and experimental results are presented to confirm the effectiveness of the proposed control strategy.

Keywords: Doubly fed Induction Generator, grid side converter, machine side converter, dc link, feedback linearization.

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2279 Optimization Approaches for a Complex Dairy Farm Simulation Model

Authors: Jagannath Aryal, Don Kulasiri, Dishi Liu

Abstract:

This paper describes the optimization of a complex dairy farm simulation model using two quite different methods of optimization, the Genetic algorithm (GA) and the Lipschitz Branch-and-Bound (LBB) algorithm. These techniques have been used to improve an agricultural system model developed by Dexcel Limited, New Zealand, which describes a detailed representation of pastoral dairying scenarios and contains an 8-dimensional parameter space. The model incorporates the sub-models of pasture growth and animal metabolism, which are themselves complex in many cases. Each evaluation of the objective function, a composite 'Farm Performance Index (FPI)', requires simulation of at least a one-year period of farm operation with a daily time-step, and is therefore computationally expensive. The problem of visualization of the objective function (response surface) in high-dimensional spaces is also considered in the context of the farm optimization problem. Adaptations of the sammon mapping and parallel coordinates visualization are described which help visualize some important properties of the model-s output topography. From this study, it is found that GA requires fewer function evaluations in optimization than the LBB algorithm.

Keywords: Genetic Algorithm, Linux Cluster, LipschitzBranch-and-Bound, Optimization

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2278 Economic Efficiency of Cassava Production in Nimba County, Liberia: An Output-Oriented Approach

Authors: Kollie B. Dogba, Willis Oluoch-Kosura, Chepchumba Chumo

Abstract:

In Liberia, many of the agricultural households cultivate cassava for either sustenance purposes, or to generate farm income. Many of the concentrated cassava farmers reside in Nimba, a north-eastern County that borders two other economies: the Republics of Cote D’Ivoire and Guinea. With a high demand for cassava output and products in emerging Asian markets coupled with an objective of the Liberia agriculture policies to increase the competitiveness of valued agriculture crops; there is a need to examine the level of resource-use efficiency for many agriculture crops. However, there is a scarcity of information on the efficiency of many agriculture crops, including cassava. Hence the study applying an output-oriented method seeks to assess the economic efficiency of cassava farmers in Nimba County, Liberia. A multi-stage sampling technique was employed to generate a sample for the study. From 216 cassava farmers, data related to on-farm attributes, socio-economic and institutional factors were collected. The stochastic frontier models, using the Translog functional forms, of production and revenue, were used to determine the level of revenue efficiency and its determinants. The result showed that most of the cassava farmers are male (60%). Many of the farmers are either married, engaged or living together with a spouse (83%), with a mean household size of nine persons. Farmland is prevalently obtained by inheritance (95%), average farm size is 1.34 hectares, and most cassava farmers did not access agriculture credits (76%) and extension services (91%). The mean cassava output per hectare is 1,506.02 kg, which estimates average revenue of L$23,551.16 (Liberian dollars). Empirical results showed that the revenue efficiency of cassava farmers varies from 0.1% to 73.5%; with the mean revenue efficiency of 12.9%. This indicates that on average, there is a vast potential of 87.1% to increase the economic efficiency of cassava farmers in Nimba by improving technical and allocative efficiencies. For the significant determinants of revenue efficiency, age and group membership had negative effects on revenue efficiency of cassava production; while farming experience, access to extension, formal education, and average wage rate have positive effects. The study recommends the setting-up and incentivizing of farmer field schools for cassava farmers to primarily share their farming experiences with others and to learn robust cultivation techniques of sustainable agriculture. Also, farm managers and farmers should consider a fix wage rate in labor contracts for all stages of cassava farming.

Keywords: Economic efficiency, frontier production, and revenue functions, Liberia, Nimba County, output-oriented, revenue efficiency.

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2277 Advanced Pulse Width Modulation Techniques for Z Source Multi Level Inverter

Authors: B. M. Manjunatha, D. V. Ashok Kumar, M. Vijay Kumar

Abstract:

This paper proposes five level diode clamped Z source Inverter. The existing PWM techniques used for ZSI are restricted for two level. The two level Z Source Inverter have high harmonic distortions which effects the performance of the grid connected PV system. To improve the performance of the system the number of voltage levels in the output waveform need to be increased. This paper presents comparative analysis of a five level diode clamped Z source Inverter with different carrier based Modified Pulse Width Modulation techniques. The parameters considered for comparison are output voltage, voltage gain, voltage stress across switch and total harmonic distortion when powered by same DC supply. Analytical results are verified using MATLAB.

Keywords: Diode Clamped, Pulse Width Modulation, total harmonic distortion, Z Source Inverter.

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2276 Response of BGA-Urea Fertigation as N2 Source on Growth Parameters and Yield of Paddy (Oryza sativa L.) in Agra (India)

Authors: Guru Prasad Satsangi, Sanjay Yadav

Abstract:

Paddy being cultivated since about 10,000 years B.C in Ganga Valley in India, its production reached up to 99 million tons in the year 2012. BGA are of much ecological importance for maintaining the soil fertility and reclaiming the alkalinity. In present investigation attempts were made to identify the local cyanobacterial genera from the paddy fields, BGA application for green farming enabling the paddy to utilize more amount of nitrogen released and to examine its impact along with Urea upon growth and yield responses of the Paddy crop. It was observed that combined treatment of BGA with Urea proved better response in almost all growth parameters and yield attributes except number of tillers/ Plant and grains/ panicle as compared to application of either Urea or BGA alone. The Paddy growers should be encouraged to adopt BGA along with Urea as source of Nitrogen for Paddy cultivation.

Keywords: BGA/Urea fertigation, Response, Paddy.

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2275 Design of Two-Channel Quadrature Mirror Filter Banks Using Digital All-Pass Filters

Authors: Ju-Hong Lee, Yi-Lin Shieh

Abstract:

The paper deals with the minimax design of two-channel linear-phase (LP) quadrature mirror filter (QMF) banks using infinite impulse response (IIR) digital all-pass filters (DAFs). Based on the theory of two-channel QMF banks using two IIR DAFs, the design problem is appropriately formulated to result in an appropriate Chebyshev approximation for the desired group delay responses of the IIR DAFs and the magnitude response of the low-pass analysis filter. Through a frequency sampling and iterative approximation method, the design problem can be solved by utilizing a weighted least squares approach. The resulting two-channel QMF banks can possess approximately LP response without magnitude distortion. Simulation results are presented for illustration and comparison.

Keywords: Chebyshev approximation, Digital All-Pass Filter, Quadrature Mirror Filter, Weighted Least Squares.

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2274 Blind Impulse Response Identification of Frequency Radio Channels: Application to Bran A Channel

Authors: S. Safi, M. Frikel, M. M'Saad, A. Zeroual

Abstract:

This paper describes a blind algorithm for estimating a time varying and frequency selective fading channel. In order to identify blindly the impulse response of these channels, we have used Higher Order Statistics (HOS) to build our algorithm. In this paper, we have selected two theoretical frequency selective channels as the Proakis-s 'B' channel and the Macchi-s channel, and one practical frequency selective fading channel called Broadband Radio Access Network (BRAN A). The simulation results in noisy environment and for different data input channel, demonstrate that the proposed method could estimate the phase and magnitude of these channels blindly and without any information about the input, except that the input excitation is i.i.d (Identically and Independent Distributed) and non-Gaussian.

Keywords: Frequency response, system identification, higher order statistics, communication channels, phase estimation.

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2273 Gas Sensing Properties of SnO2 Thin Films Modified by Ag Nanoclusters Synthesized by SILD Method

Authors: G. Korotcenkov, B. K. Cho, L. B. Gulina, V. P. Tolstoy

Abstract:

The effect of SnO2 surface modification by Ag nanoclusters, synthesized by SILD method, on the operating characteristics of thin film gas sensors was studied and models for the promotional role of Ag additives were discussed. It was found that mentioned above approach can be used for improvement both the sensitivity and the rate of response of the SnO2-based gas sensors to CO and H2. At the same time, the presence of the Ag clusters on the surface of SnO2 depressed the sensor response to ozone.

Keywords: Ag nanoparticles, deposition, characterization, gas sensors, optimization.

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2272 Dynamic Response of Fixed-base Core-tube and Base-isolated Frame Structure Subjected to Strong Earthquake Motions

Authors: Z.D. Yang, E.S.S. Lam

Abstract:

Considering the merits and limitations of energy dissipation system, seismic isolation system and suspension system, a new earthquake resistant system is proposed and is demonstrated numerically through a frame-core structure. Base isolators and story isolators are installed in the proposed system. The former “isolates" the frame from the foundation and the latter “separates" the frame from the center core. Equations of motion are formulated to study the response of the proposed structural system to strong earthquake motion. As compared with the fixed-base building system, the proposed structural system shows substantial reduction on structural response.

Keywords: Base Isolator, Core-tube, Isolated frame, Seismic Mitigation, Story Isolator

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2271 Bibliometric Analysis of the Impact of Funding on Scientific Development of Researchers

Authors: Ashkan Ebadi, Andrea Schiffauerova

Abstract:

Every year, a considerable amount of money is being invested on research, mainly in the form of funding allocated to universities and research institutes. To better distribute the available funds and to set the most proper R&D investment strategies for the future, evaluation of the productivity of the funded researchers and the impact of such funding is crucial. In this paper, using the data on 15 years of journal publications of the NSERC (Natural Sciences and Engineering research Council of Canada) funded researchers and by means of bibliometric analysis, the scientific development of the funded researchers and their scientific collaboration patterns will be investigated in the period of 1996-2010. According to the results it seems that there is a positive relation between the average level of funding and quantity and quality of the scientific output. In addition, whenever funding allocated to the researchers has increased, the number of co-authors per paper has also augmented. Hence, the increase in the level of funding may enable researchers to get involved in larger projects and/or scientific teams and increase their scientific output respectively.

Keywords: Bibliometrics, Collaboration, Funding, Productivity.

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2270 Optical Multicast over OBS Networks: An Approach Based On Code-Words and Tunable Decoders

Authors: Maha Sliti, Walid Abdallah, Noureddine Boudriga

Abstract:

In the frame of this work, we present an optical multicasting approach based on optical code-words. Our approach associates, in the edge node, an optical code-word to a group multicast address. In the core node, a set of tunable decoders are used to send a traffic data to multiple destinations based on the received code-word. The use of code-words, which correspond to the combination of an input port and a set of output ports, allows the implementation of an optical switching matrix. At the reception of a burst, it will be delayed in an optical memory. And, the received optical code-word is split to a set of tunable optical decoders. When it matches a configured code-word, the delayed burst is switched to a set of output ports.

Keywords: Optical multicast, optical burst switching networks, optical code-words, tunable decoder, virtual optical memory.

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2269 Optical Multicast over OBS Networks: An Approach Based On Code-Words and Tunable Decoders

Authors: Maha Sliti, Walid Abdallah, Noureddine Boudriga

Abstract:

In the frame of this work, we present an optical multicasting approach based on optical code-words. Our approach associates, in the edge node, an optical code-word to a group multicast address. In the core node, a set of tunable decoders are used to send a traffic data to multiple destinations based on the received code-word. The use of code-words, which correspond to the combination of an input port and a set of output ports, allows the implementation of an optical switching matrix. At the reception of a burst, it will be delayed in an optical memory. And, the received optical code-word is split to a set of tunable optical decoders. When it matches a configured code-word, the delayed burst is switched to a set of output ports.

Keywords: Optical multicast, optical burst switching networks, optical code-words, tunable decoder, virtual optical memory.

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2268 Low Cost Real Time Robust Identification of Impulsive Signals

Authors: R. Biondi, G. Dys, G. Ferone, T. Renard, M. Zysman

Abstract:

This paper describes an automated implementable system for impulsive signals detection and recognition. The system uses a Digital Signal Processing device for the detection and identification process. Here the system analyses the signals in real time in order to produce a particular response if needed. The system analyses the signals in real time in order to produce a specific output if needed. Detection is achieved through normalizing the inputs and comparing the read signals to a dynamic threshold and thus avoiding detections linked to loud or fluctuating environing noise. Identification is done through neuronal network algorithms. As a setup our system can receive signals to “learn” certain patterns. Through “learning” the system can recognize signals faster, inducing flexibility to new patterns similar to those known. Sound is captured through a simple jack input, and could be changed for an enhanced recording surface such as a wide-area recorder. Furthermore a communication module can be added to the apparatus to send alerts to another interface if needed.

Keywords: Sound Detection, Impulsive Signal, Background Noise, Neural Network.

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2267 Behavioral Response of Bee Farmers to Climate Change in South East, Nigeria

Authors: Jude A. Mbanasor, Chigozirim N. Onwusiribe

Abstract:

The enigma climate change is no longer an illusion but a reality. In the recent years, the Nigeria climate has changed and the changes are shown by the changing patterns of rainfall, the sunshine, increasing level carbon and nitrous emission as well as deforestation. This study analyzed the behavioural response of bee keepers to variations in the climate and the adaptation techniques developed in response to the climate variation. Beekeeping is a viable economic activity for the alleviation of poverty as the products include honey, wax, pollen, propolis, royal jelly, venom, queens, bees and their larvae and are all marketable. The study adopted the multistage sampling technique to select 120 beekeepers from the five states of Southeast Nigeria. Well-structured questionnaires and focus group discussions were adopted to collect the required data. Statistical tools like the Principal component analysis, data envelopment models, graphs, and charts were used for the data analysis. Changing patterns of rainfall and sunshine with the increasing rate of deforestation had a negative effect on the habitat of the bees. The bee keepers have adopted the Kenya Top bar and Langstroth hives and they establish the bee hives on fallow farmland close to the cultivated communal farms with more flowering crops.

Keywords: Climate, smart, smallholder, farmer, socioeconomic, response.

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2266 Theoretical Investigations on Different Casing and Rotor Diameters Ratio to Optimize Shaft Output of a Vaned Type Air Turbine

Authors: Bharat Raj Singh, Onkar Singh

Abstract:

This paper details a new concept of using compressed air as a potential zero pollution power source for motorbikes. In place of an internal combustion engine, the motorbike is equipped with an air turbine transforms the energy of the compressed air into shaft work. The mathematical modeling and performance evaluation of a small capacity compressed air driven vaned type novel air turbine is presented in this paper. The effect of isobaric admission and adiabatic expansion of high pressure air for different rotor diameters, casing diameters and ratio of rotor to casing diameters of the turbine have been considered and analyzed. It is concluded that the work output is found optimum for some typical values of rotor / casing diameter ratios. In this study, the maximum power works out to 3.825 kW (5.20 HP) for casing diameter of 200 mm and rotor to casing diameter ratio of 0.65 to 0.60 which is sufficient to run motorbike.

Keywords: zero pollution, compressed air, air turbine, injectionangle, rotor / casing diameter ratio.

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2265 Performance of Steel Frame with a Viscoelastic Damper Device under Earthquake Excitation

Authors: M. H. Mehrabi, S. S. Ghodsi, Zainah Ibrahim, Meldi Suhatril

Abstract:

Standard routes for upgrading existing buildings to improve their seismic response can be expensive in terms of both time and cost due to the modifications required to the foundations. As a result, interest has grown in the installation of viscoelastic dampers (VEDs) in mid and high-rise buildings. Details of a low-cost viscoelastic passive control device, the rotary rubber braced damper (RRBD), are presented in this paper. This design has the added benefits of being lightweight and simple to install. Experimental methods and finite element modeling were used to assess the performance of the proposed VED design and its effect on building response during earthquakes. The analyses took into account the behaviors of non-linear materials and large deformations. The results indicate that the proposed RRBD provides high levels of energy absorption, ensuring the stable cyclical response of buildings in all scenarios considered. In addition, time history analysis was employed in this study to evaluate the RRBD’s ability to control the displacements and accelerations experienced by steel frame structures. It was demonstrated that the device responds well even at low displacements, highlighting its suitability for use in seismic events of varying severity.

Keywords: Dynamic response, passive control, performance test, seismic protection.

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2264 Design of an Stable GPC for Nonminimum Phase LTI Systems

Authors: Mahdi Yaghobi, Mohammad Haeri

Abstract:

The current methods of predictive controllers are utilized for those processes in which the rate of output variations is not high. For such processes, therefore, stability can be achieved by implementing the constrained predictive controller or applying infinite prediction horizon. When the rate of the output growth is high (e.g. for unstable nonminimum phase process) the stabilization seems to be problematic. In order to avoid this, it is suggested to change the method in the way that: first, the prediction error growth should be decreased at the early stage of the prediction horizon, and second, the rate of the error variation should be penalized. The growth of the error is decreased through adjusting its weighting coefficients in the cost function. Reduction in the error variation is possible by adding the first order derivate of the error into the cost function. By studying different examples it is shown that using these two remedies together, the closed-loop stability of unstable nonminimum phase process can be achieved.

Keywords: GPC, Stability, Varying Weighting Coefficients.

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