Search results for: Variable compression ratio CI engine
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3250

Search results for: Variable compression ratio CI engine

1960 Optical Switching Based On Bragg Solitons in A Nonuniform Fiber Bragg Grating

Authors: Abdulatif Abdusalam, Mohamed Shaban

Abstract:

In this paper, we consider the nonlinear pulse propagation through a nonuniform birefringent fiber Bragg grating (FBG) whose index modulation depth varies along the propagation direction. Here, the pulse propagation is governed by the nonlinear birefringent coupled mode (NLBCM) equations. To form the Bragg soliton outside the photonic bandgap (PBG), the NLBCM equations are reduced to the well known NLS type equation by multiple scale analysis. As we consider the pulse propagation in a nonuniform FBG, the pulse propagation outside the PBG is governed by inhomogeneous NLS (INLS) rather than NLS. We then discuss the formation of soliton in the FBG known as Bragg soliton whose central frequency lies outside but close to the PBG of the grating structure. Further, we discuss Bragg soliton compression due to a delicate balance between the SPM and the varying grating induced dispersion. In addition, Bragg soliton collision, Bragg soliton switching and possible logic gates have also been discussed.

Keywords: Bragg grating, Nonuniform fiber, Nonlinear pulse.

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1959 Effect of Birks Constant and Defocusing Parameter on Triple-to-Double Coincidence Ratio Parameter in Monte Carlo Simulation-GEANT4

Authors: F. Abubaker, F. Tortorici, M. Capogni, C. Sutera, V. Bellini

Abstract:

This project concerns with the detection efficiency of the portable Triple-to-Double Coincidence Ratio (TDCR) at the National Institute of Metrology of Ionizing Radiation (INMRI-ENEA) which allows direct activity measurement and radionuclide standardization for pure-beta emitter or pure electron capture radionuclides. The dependency of the simulated detection efficiency of the TDCR, by using Monte Carlo simulation Geant4 code, on the Birks factor (kB) and defocusing parameter has been examined especially for low energy beta-emitter radionuclides such as 3H and 14C, for which this dependency is relevant. The results achieved in this analysis can be used for selecting the best kB factor and the defocusing parameter for computing theoretical TDCR parameter value. The theoretical results were compared with the available ones, measured by the ENEA TDCR portable detector, for some pure-beta emitter radionuclides. This analysis allowed to improve the knowledge of the characteristics of the ENEA TDCR detector that can be used as a traveling instrument for in-situ measurements with particular benefits in many applications in the field of nuclear medicine and in the nuclear energy industry.

Keywords: Birks constant, defocusing parameter, GEANT4 code, TDCR parameter.

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1958 Numerical Simulation of Wall Treatment Effects on the Micro-Scale Combustion

Authors: R. Kamali, A. R. Binesh, S. Hossainpour

Abstract:

To understand working features of a micro combustor, a computer code has been developed to study combustion of hydrogen–air mixture in a series of chambers with same shape aspect ratio but various dimensions from millimeter to micrometer level. The prepared algorithm and the computer code are capable of modeling mixture effects in different fluid flows including chemical reactions, viscous and mass diffusion effects. The effect of various heat transfer conditions at chamber wall, e.g. adiabatic wall, with heat loss and heat conduction within the wall, on the combustion is analyzed. These thermal conditions have strong effects on the combustion especially when the chamber dimension goes smaller and the ratio of surface area to volume becomes larger. Both factors, such as larger heat loss through the chamber wall and smaller chamber dimension size, may lead to the thermal quenching of micro-scale combustion. Through such systematic numerical analysis, a proper operation space for the micro-combustor is suggested, which may be used as the guideline for microcombustor design. In addition, the results reported in this paper illustrate that the numerical simulation can be one of the most powerful and beneficial tools for the micro-combustor design, optimization and performance analysis.

Keywords: Numerical simulation, Micro-combustion, MEMS, CFD, Chemical reaction.

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1957 Automatic Text Summarization

Authors: Mohamed Abdel Fattah, Fuji Ren

Abstract:

This work proposes an approach to address automatic text summarization. This approach is a trainable summarizer, which takes into account several features, including sentence position, positive keyword, negative keyword, sentence centrality, sentence resemblance to the title, sentence inclusion of name entity, sentence inclusion of numerical data, sentence relative length, Bushy path of the sentence and aggregated similarity for each sentence to generate summaries. First we investigate the effect of each sentence feature on the summarization task. Then we use all features score function to train genetic algorithm (GA) and mathematical regression (MR) models to obtain a suitable combination of feature weights. The proposed approach performance is measured at several compression rates on a data corpus composed of 100 English religious articles. The results of the proposed approach are promising.

Keywords: Automatic Summarization, Genetic Algorithm, Mathematical Regression, Text Features.

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1956 Buckling Resistance of Basalt Fiber Reinforced Polymer Infill Panel Subjected to Elevated Temperatures

Authors: Viriyavudh Sim, Woo Young Jung

Abstract:

Performance of Basalt Fiber Reinforced Polymer (BFRP) sandwich infill panel system under diagonal compression was studied by means of numerical analysis. Furthermore, the variation of temperature was considered to affect the mechanical properties of BFRP, since their composition was based on polymeric material. Moreover, commercial finite element analysis platform ABAQUS was used to model and analyze this infill panel system. Consequently, results of the analyses show that the overall performance of BFRP panel had a 15% increase compared to that of GFRP infill panel system. However, the variation of buckling load in terms of temperature for the BFRP system showed a more sensitive nature compared to those of GFRP system.

Keywords: Basalt Fiber Reinforced Polymer, Buckling performance, numerical simulation, temperature dependent materials.

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1955 Robust and Transparent Spread Spectrum Audio Watermarking

Authors: Ali Akbar Attari, Ali Asghar Beheshti Shirazi

Abstract:

In this paper, we propose a blind and robust audio watermarking scheme based on spread spectrum in Discrete Wavelet Transform (DWT) domain. Watermarks are embedded in the low-frequency coefficients, which is less audible. The key idea is dividing the audio signal into small frames, and magnitude of the 6th level of DWT approximation coefficients is modifying based upon the Direct Sequence Spread Spectrum (DSSS) technique. Also, the psychoacoustic model for enhancing in imperceptibility, as well as Savitsky-Golay filter for increasing accuracy in extraction, is used. The experimental results illustrate high robustness against most common attacks, i.e. Gaussian noise addition, Low pass filter, Resampling, Requantizing, MP3 compression, without significant perceptual distortion (ODG is higher than -1). The proposed scheme has about 83 bps data payload.

Keywords: Audio watermarking, spread spectrum, discrete wavelet transform, psychoacoustic, Savitsky-Golay filter.

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1954 Evaluation of Forage Yield and Competition Indices for Intercropped Barley and Legumes

Authors: Abdollah Javanmard, Fariborz Shekari, Hasan Dehghanian

Abstract:

Barley (Hordeum vulgare L.), vetch (Vicia villosa), and grass pea (Lathyrus sativus L.) monocultures as well as mixtures of barley with each of the above legumes, in three seeding ratios (i.e., barley: legume 75:25, 50:50 and 25:75, based on seed numbers) were used to investigated forage yield and competition indices. The results showed that intercropping reduced the dry matter yield of the three component plants, compared with their respective monocrops. The greatest value of total dry matter yield was obtained from barley25- grasspea75 (5.44 t ha-1) mixture, followed by grass pea sole crop (4.99 t ha-1). The total actual yield loss (AYL) values were positive and greater than 0 in all mixtures, indicating an advantage from intercropping over sole crops. Intercropped barley had a higher relative crowding coefficient (K=1.64) than intercropped legumes (K=1.20), indicating that barley was more competitive than legumes in mixtures. Furthermore, grass pea was more competitive than vetch in mixtures with barley. The highest land equivalent ratio (LER), system productivity index (SPI) and monetary advantage index (MAI) were obtained when barley was mixed at a rate of 25% with 75% seed rate of grass pea. It is concluded that intercropping of barley with grass pea has a good potential to improve the performance of forage with high land-use efficiency.

Keywords: Forage, grass pea, intercropping, land equivalent ratio (LER), monetary advantage.

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1953 Effect of Chemical Pretreatments and Dehydration Methods on Quality Characteristics of Tomato Powder and Its Storage Stability

Authors: Reihaneh Ahmadzadeh Ghavidel, Mehdi Ghiafeh Davoodi

Abstract:

Dehydration process was carried out for tomato slices of var. Avinash after giving different pre-treatments such as calcium chloride (CaCl2), potassium metabisulphite (KMS), calcium chloride and potassium metabisulphite (CaCl2 +KMS), and sodium chloride (NaCl). Untreated samples served as control. Solar drier and continuous conveyor (tunnel) drier were used for dehydration. Quality characteristics of tomato slices viz. moisture content, sugar, titratable acidity, lycopene content, dehydration ratio, rehydration ratio and non-enzymatic browning as affected by dehydration process were studied. Storage study was also carried out for a period of six months for tomato powder packed into different types of packaging materials viz. metalized polyester (MP) film and low density poly ethylene (LDPE). Changes in lycopene content and non-enzymatic browning (NEB) were estimated during storage at room temperature. Pretreatment of 5 mm thickness of tomato slices with calcium chloride in combination with potassium metabisulphite and drying using a tunnel drier with subsequent storage of product in metalized polyester bags was selected as the best process.

Keywords: Drying pretreatments, Solar drying, Tomato powder, Tunnel drying

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1952 Incorporation Mechanism of Stabilizing Simulated Lead-Laden Sludge in Aluminum-Rich Ceramics

Authors: Xingwen Lu, Kaimin Shih

Abstract:

This study investigated a strategy of blending lead-laden sludge and Al-rich precursors to reduce the release of metals from the stabilized products. Using PbO as the simulated lead-laden sludge to sinter with γ-Al2O3 by Pb:Al molar ratios of 1:2 and 1:12, PbAl2O4 and PbAl12O19 were formed as final products during the sintering process, respectively. By firing the PbO + γ-Al2O3 mixtures with different Pb/Al molar ratios at 600 to 1000 °C, the lead transformation was determined through X-ray diffraction (XRD) data. In Pb/Al molar ratio of 1/2 system, the formation of PbAl2O4 is initiated at 700 °C, but an effective formation was observed above 750 °C. An intermediate phase, Pb9Al8O21, was detected in the temperature range of 800-900 °C. However, different incorporation behavior for sintering PbO with Al-rich precursors at a Pb/Al molar ratio of 1/12 was observed during the formation of PbAl12O19 in this system. In the sintering process, both temperature and time effect on the formation of PbAl2O4 and PbAl12O19 phases were estimated. Finally, a prolonged leaching test modified from the U.S. Environmental Protection Agency-s toxicity characteristic leaching procedure (TCLP) was used to evaluate the durability of PbO, Pb9Al8O21, PbAl2O4 and PbAl12O19 phases. Comparison for the leaching results of the four phases demonstrated the higher intrinsic resistance of PbAl12O19 against acid attack.

Keywords: Sludge, Lead, Stabilization, Leaching behavior

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1951 Numerical Investigation on the Progressive Collapse Resistance of an RC Building with Brick Infills under Column Loss

Authors: Meng-Hao Tsai, Tsuei-Chiang Huang

Abstract:

Interior brick-infill partitions are usually considered as non-structural components and only their weight is accounted for in practical structural design. In this study, their effect on the progressive collapse resistance of an RC building subjected to sudden column loss is investigated. Three notional column loss conditions with four different brick-infill locations are considered. Column-loss response analyses of the RC building with and without brick infills are carried out. Analysis results indicate that the collapse resistance is only slightly influenced by the brick infills due to their brittle failure characteristic. Even so, they may help to reduce the inelastic displacement response under column loss. For practical engineering, it is reasonably conservative to only consider the weight of brick-infill partitions in the structural analysis.

Keywords: Progressive collapse, column loss, brick-infill partition, compression strut.

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1950 Acoustic and Flow Field Analysis of a Perforated Muffler Design

Authors: Zeynep Parlar, Şengül Ari, Rıfat Yilmaz, Erdem Özdemir, Arda Kahraman

Abstract:

New regulations and standards for noise emission increasingly compel the automotive firms to make some improvements about decreasing the engine noise. Nowadays, the perforated reactive mufflers which have an effective damping capability are specifically used for this purpose. New designs should be analyzed with respect to both acoustics and back pressure. In this study, a reactive perforated muffler is investigated numerically and experimentally. For an acoustical analysis, the transmission loss which is independent of sound source of the present cross flow, the perforated muffler was analyzed by COMSOL. To be able to validate the numerical results, transmission loss was measured experimentally. Back pressure was obtained based on the flow field analysis and was also compared with experimental results. Numerical results have an approximate error of 20% compared to experimental results.

Keywords: Back Pressure, Perforated Muffler, Transmission Loss.

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1949 Conversion in Chemical Reactors using Hollow Cylindrical Catalyst Pellet

Authors: Mohammad Asif

Abstract:

Heterogeneous catalysis is vital for a number of chemical, refinery and pollution control processes. The use of catalyst pellets of hollow cylindrical shape provide several distinct advantages over other common shapes, and can therefore help to enhance conversion levels in reactors. A better utilization of the catalytic material is probably most notable of these features due to the absence of the pellet core, which helps to significantly lower the effect of the internal transport resistance. This is reflected in the enhancement of the effectiveness factor. For the case of the first order irreversible kinetics, a substantial increase in the effectiveness factor can be obtained by varying shape parameters. Important shape parameters of a finite hollow cylinder are the ratio of the inside to the outside radii (κ) and the height to the diameter ratio (γ). A high value of κ the generally helps to enhance the effectiveness factor. On the other hand, lower values of the effectiveness factors are obtained when the dimension of the height and the diameter are comparable. Thus, the departure of parameter γ from the unity favors higher effectiveness factor. Since a higher effectiveness factor is a measure of a greater utilization of the catalytic material, higher conversion levels can be achieved using the hollow cylindrical pellets possessing optimized shape parameters.

Keywords: Finite hollow cylinder, Catalyst pellet, Effectiveness factor, Thiele Modulus, Conversion

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1948 Effect of Transmission Codes on Hybrid SC/MRC Diversity Reception MQAM system over Rayleigh Fading Channels

Authors: J.S. Ubhi, M.S. Patterh, T.S. Kamal

Abstract:

In this paper, the effect of transmission codes on the performance of coherent square M-ary quadrature amplitude modulation (CSMQAM) under hybrid selection/maximal-ratio combining (H-S/MRC) diversity is analysed. The fading channels are modeled as frequency non-selective slow independent and identically distributed Rayleigh fading channels corrupted by additive white Gaussian noise (AWGN). The results for coded MQAM are computed numerically for the case of (24,12) extended Golay code and compared with uncoded MQAM under H-S/MRC diversity by plotting error probabilities versus average signal to noise ratio (SNR) for various values L and N in order to examine the improvement in the performance of the digital communications system as the number of selected diversity branches is increased. The results for no diversity, conventional SC and Lth order MRC schemes are also plotted for comparison. Closed form analytical results derived in this paper are sufficiently simple and therefore can be computed numerically without any approximations. The analytical results presented in this paper are expected to provide useful information needed for design and analysis of digital communication systems over wireless fading channels.

Keywords: Error probability, diversity reception, Rayleigh fading channels, wireless digital communications.

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1947 Fabrication of Single Crystal of Mg Alloys Containing Rare Earth Elements

Authors: Joon Ho Kim, Tae Kwon Ha

Abstract:

Single crystals of Magnesium alloys such as Mg-1Al, Mg-1Zn-0.5Y, Mg-3Li, and AZ31 alloys were successfully fabricated in this study by employing the modified Bridgman method. Single crystals of pure Mg were also made in this study. To determine the exact orientation of crystals, Laue back-reflection method and pole figure measurement were carried out on each single crystal. Dimensions of single crystals were 10 mm in diameter and 120 mm in length. Hardness and compression tests were conducted and the results revealed that hardness and the strength strongly depended on the orientation. The closer to basal one the orientation was, the higher hardness and compressive strength were. The effect of alloying was not higher than that of orientation. After compressive deformation of single crystals, the orientation of the crystals was found to rotate and to be parallel to the basal orientation.

Keywords: Compressive strength, Hardness, Mg alloys, Modified Bridgman method, Orientation, Pole figure, Single crystal.

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1946 The Reproducibility and Repeatability of Modified Likelihood Ratio for Forensics Handwriting Examination

Authors: O. Abiodun Adeyinka, B. Adeyemo Adesesan

Abstract:

The forensic use of handwriting depends on the analysis, comparison, and evaluation decisions made by forensic document examiners. When using biometric technology in forensic applications, it is necessary to compute Likelihood Ratio (LR) for quantifying strength of evidence under two competing hypotheses, namely the prosecution and the defense hypotheses wherein a set of assumptions and methods for a given data set will be made. It is therefore important to know how repeatable and reproducible our estimated LR is. This paper evaluated the accuracy and reproducibility of examiners' decisions. Confidence interval for the estimated LR were presented so as not get an incorrect estimate that will be used to deliver wrong judgment in the court of Law. The estimate of LR is fundamentally a Bayesian concept and we used two LR estimators, namely Logistic Regression (LoR) and Kernel Density Estimator (KDE) for this paper. The repeatability evaluation was carried out by retesting the initial experiment after an interval of six months to observe whether examiners would repeat their decisions for the estimated LR. The experimental results, which are based on handwriting dataset, show that LR has different confidence intervals which therefore implies that LR cannot be estimated with the same certainty everywhere. Though the LoR performed better than the KDE when tested using the same dataset, the two LR estimators investigated showed a consistent region in which LR value can be estimated confidently. These two findings advance our understanding of LR when used in computing the strength of evidence in handwriting using forensics.

Keywords: Logistic Regression LoR, Kernel Density Estimator KDE, Handwriting, Confidence Interval, Repeatability, Reproducibility.

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1945 Walsh-Hadamard Transform for Facial Feature Extraction in Face Recognition

Authors: M. Hassan, I. Osman, M. Yahia

Abstract:

This Paper proposes a new facial feature extraction approach, Wash-Hadamard Transform (WHT). This approach is based on correlation between local pixels of the face image. Its primary advantage is the simplicity of its computation. The paper compares the proposed approach, WHT, which was traditionally used in data compression with two other known approaches: the Principal Component Analysis (PCA) and the Discrete Cosine Transform (DCT) using the face database of Olivetti Research Laboratory (ORL). In spite of its simple computation, the proposed algorithm (WHT) gave very close results to those obtained by the PCA and DCT. This paper initiates the research into WHT and the family of frequency transforms and examines their suitability for feature extraction in face recognition applications.

Keywords: Face Recognition, Facial Feature Extraction, Principal Component Analysis, and Discrete Cosine Transform, Wash-Hadamard Transform.

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1944 Study The Effects of Conventional and Low Input Production System on Energy Efficiency of Silybum marianum L.

Authors: M. Haj Seyed Hadi, M. Darzi, E. Sharifi Ashoorabadi

Abstract:

Medicinal plants are most suitable crops for ecological production systems because of their role in human health and the aim of sustainable agriculture to improve ecosystem efficiency and its products quality. Calculations include energy output (contents of energy in seed) and energy inputs (consumption of fertilizers, pesticides, labor, machines, fuel and electricity). The ratio of output of the production to inputs is called the energy outputs / inputs ratio or energy efficiency. One way to quantify essential parts of agricultural development is the energy flow method. The output / input energy ratio is proposed as the most comprehensive single factor in pursuing the objective of sustainability. Sylibum marianum L. is one of the most important medicinal plants in Iran and has effective role on health of growing population in Iran. The objective of this investigation was to find out energy efficiency in conventional and low input production system of Milk thistle. This investigation was carried out in the spring of 2005 – 2007 in the Research Station of Rangelands in Hamand - Damavand region of IRAN. This experiment was done in split-split plot based on randomized complete block design with 3 replications. Treatments were 2 production systems (Conventional and Low input system) in the main plots, 3 planting time (25 of March, 4 and 14 of April) in the sub plots and 2 seed types (Improved and Native of Khoozestan) in the sub-sub plots. Results showed that in conventional production system energy efficiency, because of higher inputs and less seed yield, was less than low input production system. Seed yield was 1199.5 and 1888 kg/ha in conventional and low input systems, respectively. Total energy inputs and out puts for conventional system was 10068544.5 and 7060515.9 kcal. These amounts for low input system were 9533885.6 and 11113191.8 kcal. Results showed that energy efficiency for seed production in conventional and low input system was 0.7 and 1.16, respectively. So, milk thistle seed production in low input system has 39.6 percent higher energy efficiency than conventional production system. Also, higher energy efficiency were found in sooner planting time (25 of March) and native seed of Khoozestan.

Keywords: energy efficiency, milk thistle, production system

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1943 Statistical Measures and Optimization Algorithms for Gene Selection in Lung and Ovarian Tumor

Authors: C. Gunavathi, K. Premalatha

Abstract:

Microarray technology is universally used in the study of disease diagnosis using gene expression levels. The main shortcoming of gene expression data is that it includes thousands of genes and a small number of samples. Abundant methods and techniques have been proposed for tumor classification using microarray gene expression data. Feature or gene selection methods can be used to mine the genes that directly involve in the classification and to eliminate irrelevant genes. In this paper statistical measures like T-Statistics, Signal-to-Noise Ratio (SNR) and F-Statistics are used to rank the genes. The ranked genes are used for further classification. Particle Swarm Optimization (PSO) algorithm and Shuffled Frog Leaping (SFL) algorithm are used to find the significant genes from the top-m ranked genes. The Naïve Bayes Classifier (NBC) is used to classify the samples based on the significant genes. The proposed work is applied on Lung and Ovarian datasets. The experimental results show that the proposed method achieves 100% accuracy in all the three datasets and the results are compared with previous works.

Keywords: Microarray, T-Statistics, Signal-to-Noise Ratio, FStatistics, Particle Swarm Optimization, Shuffled Frog Leaping, Naïve Bayes Classifier.

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1942 Determination of Seismic Wave of Consolidated Granite Rock in Penang Island: UltrasonicTesting Method Vs Seismic Refraction Method

Authors: Mohd Hafiz Musa, Zulfadhli Hasan Adli, M . N . Khairul Arifin

Abstract:

In seismic survey, the information regarding the velocity of compression wave (Vp) as well as shear wave (Vs) are very useful especially during the seismic interpretation. Previous studies showed that both Vp and Vs determined by above methods are totally different with respect to each other but offered good approximation. In this study, both Vp and Vs of consolidated granite rock were studied by using ultrasonic testing method and seismic refraction method. In ultrasonic testing, two different condition of rock are used which is dry and wet. The differences between Vp and Vs getting by using ultrasonic testing and seismic refraction were investigated and studied. The effect of water content in granite rock towards the value of Vp and Vs during ultrasonic testing are also measured. Within this work, the tolerance of the differences between the velocity of seismic wave getting from ultrasonic testing and the velocity of seismic wave getting from seismic refraction are also measured and investigated.

Keywords: Compressional wave, Granite, Shear Wave, Velocity

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1941 A PIM (Processor-In-Memory) for Computer Graphics : Data Partitioning and Placement Schemes

Authors: Jae Chul Cha, Sandeep K. Gupta

Abstract:

The demand for higher performance graphics continues to grow because of the incessant desire towards realism. And, rapid advances in fabrication technology have enabled us to build several processor cores on a single die. Hence, it is important to develop single chip parallel architectures for such data-intensive applications. In this paper, we propose an efficient PIM architectures tailored for computer graphics which requires a large number of memory accesses. We then address the two important tasks necessary for maximally exploiting the parallelism provided by the architecture, namely, partitioning and placement of graphic data, which affect respectively load balances and communication costs. Under the constraints of uniform partitioning, we develop approaches for optimal partitioning and placement, which significantly reduce search space. We also present heuristics for identifying near-optimal placement, since the search space for placement is impractically large despite our optimization. We then demonstrate the effectiveness of our partitioning and placement approaches via analysis of example scenes; simulation results show considerable search space reductions, and our heuristics for placement performs close to optimal – the average ratio of communication overheads between our heuristics and the optimal was 1.05. Our uniform partitioning showed average load-balance ratio of 1.47 for geometry processing and 1.44 for rasterization, which is reasonable.

Keywords: Data Partitioning and Placement, Graphics, PIM, Search Space Reduction.

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1940 A Hybrid Recommendation System Based On Association Rules

Authors: Ahmed Mohammed K. Alsalama

Abstract:

Recommendation systems are widely used in e-commerce applications. The engine of a current recommendation system recommends items to a particular user based on user preferences and previous high ratings. Various recommendation schemes such as collaborative filtering and content-based approaches are used to build a recommendation system. Most of current recommendation systems were developed to fit a certain domain such as books, articles, and movies. We propose1 a hybrid framework recommendation system to be applied on two dimensional spaces (User × Item) with a large number of Users and a small number of Items. Moreover, our proposed framework makes use of both favorite and non-favorite items of a particular user. The proposed framework is built upon the integration of association rules mining and the content-based approach. The results of experiments show that our proposed framework can provide accurate recommendations to users.

Keywords: Data Mining, Association Rules, Recommendation Systems, Hybrid Systems.

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1939 A Prospective Study on Alkali Activated Bottom Ash-GGBS Blend in Paver Blocks

Authors: V. Revathi, J. Thaarrini, M. Venkob Rao

Abstract:

This paper presents a study on use of alkali activated bottom ash (BA) and ground granulated blast furnace slag (GGBS) blend in paver blocks. A preliminary effort on alkali-activated bottom ash, blast furnace slag based geopolymer (BA-GGBS-GP) mortar with river sand was carried out to identify the suitable mix for paver block. Several mixes were proposed based on the combination of BA-GGBS. The percentage ratio of BA: GGBS was selected as 100:0, 75:25, 50:50, 25:75 and 0:100 for the source material. Sodium based alkaline activators were used for activation. The molarity of NaOH was considered as 8M. The molar ratio of SiO2 to Na2O was varied from 1 to 4. Two curing mode such as ambient and steam curing 60°C for 24 hours were selected. The properties of paver block such as compressive strength split tensile strength, flexural strength and water absorption were evaluated as per IS15658:2006. Based on the preliminary study on BA-GGBS-GP mortar, the combinations of 25% BA with 75% GGBS mix for M30 and 75% BA with 25% GGBS mix for M35 grade were identified for paver block. Test results shows that the combination of BA-GGBS geopolymer paver blocks attained remarkable compressive strength under steam curing as well as in ambient mode at 3 days. It is noteworthy to know BA-GGBS-GP has promising future in the construction industry.

Keywords: Bottom ash, GGBS, alkali activation, paver block.

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1938 Investigating what Effects Aviation Fluids Have on the Flatwise Compressive Strength of Nomex® Honeycomb Core Material

Authors: G. Kim, R. Sterkenburg

Abstract:

One of the disadvantages of honeycomb sandwich structure is that they are prone to fluid intrusion. The purpose of this study is to determine if the structural properties of honeycomb core are affected by contact with a fluid. The test specimens were manufactured of fiberglass prepreg for the facesheets and Nomex® honeycomb core for the core material in accordance with ASTM C-365/365M. Test specimens were soaked in several different kinds of fluids, such as aircraft fuel, turbine engine oil, hydraulic fluid, and water for a period of 60 days. A flatwise compressive test was performed, and the test results were analyzed to determine how the contact with aircraft fluids affected the compressive strength of the Nomex® honeycomb core and how the strength was recovered when the specimens were dry. In addition, the investigation of de-bonding between facesheet and core material after soaking were performed to support the study.

Keywords: Debonding, environmental degradation, honeycomb sandwich structure.

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1937 Investigation of the Effect of Number of Story on Different Structural Components of RC Building

Authors: Zasiah Tafheem, Mahadee Hasan Shourav, Zahidul Islam, Saima Islam Tumpa

Abstract:

The paper aims at investigating the effect of number of story on different structural components of reinforced concrete building due to gravity and lateral loading. For the study, three building models having same building plan of three, six and nine stories are analyzed and designed using software package. All the buildings are residential and are located in Dhaka city of Bangladesh. Lateral load including wind and earthquake loading are applied to the building along both longitudinal and transverse direction as per Bangladesh National Building Code (BNBC, 2006). Equivalent static force method is followed for the applied seismic loading. The present study investigates as well as compares mainly total steel requirement in different structural components for those buildings. It has been found that total longitudinal steel requirement for beams at each floor is 48.57% for three storied building, 61.36% for six storied building when the total percentage is taken as 100% in case of nine storied building. For an exterior column, the steel ratio is 2.1%, 3.06%, 4.55% for three, six and nine storied building respectively for the first three floors. In addition, it has been noted that total weight of longitudinal reinforcement of an interior column is 14.02 % for threestoried building and 43.12% for six storied building when the total reinforcement is considered 100% for nine storied building for the first three floors.

Keywords: Equivalent Static Force Method, longitudinal reinforcement, seismic loading, steel ratio.

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1936 Solar Energy Collection using a Double-layer Roof

Authors: S. Kong Wang

Abstract:

The purpose of this study is to investigate the efficiency of a double-layer roof in collecting solar energy as an application to the areas such as raising high-end temperature of organic Rankine cycle (ORC). The by-product of the solar roof is to reduce building air-conditioning loads. The experimental apparatus are arranged to evaluate the effects of the solar roof in absorbing solar energy. The flow channel is basically formed by an aluminum plate on top of a plywood plate. The geometric configurations in which the effects of absorbing energy is analyzed include: a bare uncovered aluminum plate, a glass-covered aluminum plate, a glass-covered/black-painted aluminum plate, a plate with variable lengths, a flow channel with stuffed material (in an attempt on enhancement of heat conduction), and a flow channel with variable slanted angles. The experimental results show that the efficiency of energy collection varies from 0.6 % to 11 % for the geometric configurations mentioned above. An additional study is carried out using CFD simulation to investigate the effects of fins on the aluminum plate. It shows that due to vastly enhanced heat conduction, the efficiency can reach ~23 % if 50 fins are installed on the aluminum plate. The study shows that a double-layer roof can efficiently absorb solar energy and substantially reduce building air-conditioning loads. On the high end of an organic Rankine cycle, a solar pond is used to replace the warm surface water of the sea as OTEC (ocean thermal energy conversion) is the driving energy for the ORC. The energy collected from the double-layered solar roof can be pumped into the pond and raise the pond temperature as the pond surface area is equivalently increased by nearly one-fourth of the total area of the double-layer solar roof. The effect of raising solar pond temperature is especially prominent if the double-layer solar roofs are installed in a community area.

Keywords: solar energy collection, double-layer solar roof, energy conservation, ORC, OTEC

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1935 Comparison of Different Advanced Oxidation Processes for Degrading 4-Chlorophenol

Authors: M.D. Murcia, M. Gomez, E. Gomez, J.L. Gomez, N. Christofi

Abstract:

The removal efficiency of 4-chlorophenol with different advanced oxidation processes have been studied. Oxidation experiments were carried out using two 4-chlorophenol concentrations: 100 mg L-1 and 250 mg L-1 and UV generated from a KrCl excilamp with (molar ratio H2O2: 4-chlorophenol = 25:1) and without H2O2, and, with Fenton process (molar ratio H2O2:4- chlorophenol of 25:1 and Fe2+ concentration of 5 mg L-1). The results show that there is no significant difference in the 4- chlorophenol conversion when using one of the three assayed methods. However, significant concentrations of the photoproductos still remained in the media when the chosen treatment involves UV without hydrogen peroxide. Fenton process removed all the intermediate photoproducts except for the hydroquinone and the 1,2,4-trihydroxybenzene. In the case of UV and hydrogen peroxide all the intermediate photoproducts are removed. Microbial bioassays were carried out utilising the naturally luminescent bacterium Vibrio fischeri and a genetically modified Pseudomonas putida isolated from a waste treatment plant receiving phenolic waste. The results using V. fischeri show that with samples after degradation, only the UV treatment showed toxicity (IC50 =38) whereas with H2O2 and Fenton reactions the samples exhibited no toxicity after treatment in the range of concentrations studied. Using the Pseudomonas putida biosensor no toxicity could be detected for all the samples following treatment due to the higher tolerance of the organism to phenol concentrations encountered.

Keywords: 4-chlorophenol, Fenton, photodegradation, UV, excilamp.

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1934 Objective Performance of Compressed Image Quality Assessments

Authors: Ratchakit Sakuldee, Somkait Udomhunsakul

Abstract:

Measurement of the quality of image compression is important for image processing application. In this paper, we propose an objective image quality assessment to measure the quality of gray scale compressed image, which is correlation well with subjective quality measurement (MOS) and least time taken. The new objective image quality measurement is developed from a few fundamental of objective measurements to evaluate the compressed image quality based on JPEG and JPEG2000. The reliability between each fundamental objective measurement and subjective measurement (MOS) is found. From the experimental results, we found that the Maximum Difference measurement (MD) and a new proposed measurement, Structural Content Laplacian Mean Square Error (SCLMSE), are the suitable measurements that can be used to evaluate the quality of JPEG200 and JPEG compressed image, respectively. In addition, MD and SCLMSE measurements are scaled to make them equivalent to MOS, given the rate of compressed image quality from 1 to 5 (unacceptable to excellent quality).

Keywords: JPEG, JPEG2000, objective image quality measurement, subjective image quality measurement, correlation coefficients.

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1933 CFD Modeling of a Radiator Axial Fan for Air Flow Distribution

Authors: S. Jain, Y. Deshpande

Abstract:

The fluid mechanics principle is used extensively in designing axial flow fans and their associated equipment. This paper presents a computational fluid dynamics (CFD) modeling of air flow distribution from a radiator axial flow fan used in an acid pump truck Tier4 (APT T4) Repower. This axial flow fan augments the transfer of heat from the engine mounted on the APT T4. CFD analysis was performed for an area weighted average static pressure difference at the inlet and outlet of the fan. Pressure contours, velocity vectors, and path lines were plotted for detailing the flow characteristics for different orientations of the fan blade. The results were then compared and verified against known theoretical observations and actual experimental data. This study shows that a CFD simulation can be very useful for predicting and understanding the flow distribution from a radiator fan for further research work.

Keywords: Computational fluid dynamics (CFD), acid pump truck (APT) Tier4 Repower, axial flow fan, area weighted average static pressure difference, and contour plots.

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1932 Wet Flue Gas Desulfurization Using a New O-Element Design Which Replaces the Venturi Scrubber

Authors: P. Lestinsky, D. Jecha, V. Brummer, P. Stehlik

Abstract:

Scrubbing by a liquid spraying is one of the most effective processes used for removal of fine particles and soluble gas pollutants (such as SO2, HCl, HF) from the flue gas. There are many configurations of scrubbers designed to provide contact between the liquid and gas stream for effectively capturing particles or soluble gas pollutants, such as spray plates, packed bed towers, jet scrubbers, cyclones, vortex and venturi scrubbers. The primary function of venturi scrubber is the capture of fine particles as well as HCl, HF or SO2 removal with effect of the flue gas temperature decrease before input to the absorption column. In this paper, sulfur dioxide (SO2) from flue gas was captured using new design replacing venturi scrubber (1st degree of wet scrubbing). The flue gas was prepared by the combustion of the carbon disulfide solution in toluene (1:1 vol.) in the flame in the reactor. Such prepared flue gas with temperature around 150°C was processed in designed laboratory O-element scrubber. Water was used as absorbent liquid. The efficiency of SO2 removal, pressure drop and temperature drop were measured on our experimental device. The dependence of these variables on liquid-gas ratio was observed. The average temperature drop was in the range from 150°C to 40°C. The pressure drop was increased with increasing of a liquid-gas ratio, but no too much as for the common venturi scrubber designs. The efficiency of SO2 removal was up to 70 %. The pressure drop of our new designed wet scrubber is similar to commonly used venturi scrubbers; nevertheless the influence of amount of the liquid on pressure drop is not so significant.

Keywords: Desulphurization, absorption, flue gas, modeling.

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1931 The Delaying Influence of Degradation on the Divestment of Gas Turbines for Associated Gas Utilisation: Part 1

Authors: Mafel Obhuo, Dodeye I. Igbong, Duabari S. Aziaka, Pericles Pilidis

Abstract:

An important feature of the exploitation of associated gas as fuel for gas turbine engines is a declining supply. So when exploiting this resource, the divestment of prime movers is very important as the fuel supply diminishes with time. This paper explores the influence of engine degradation on the timing of divestments. Hypothetical but realistic gas turbine engines were modelled with Turbomatch, the Cranfield University gas turbine performance simulation tool. The results were deployed in three degradation scenarios within the TERA (Techno-economic and environmental risk analysis) framework to develop economic models. An optimisation with Genetic Algorithms was carried out to maximize the economic benefit. The results show that degradation will have a significant impact. It will delay the divestment of power plants, while they are running less efficiently. Over a 20 year investment, a decrease of $0.11bn, $0.26bn and $0.45bn (billion US dollars) were observed for the three degradation scenarios as against the clean case.

Keywords: Economic return, flared associated gas, net present value, optimisation.

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