Search results for: Error diffusion method
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9130

Search results for: Error diffusion method

1330 Ultra-High Frequency Passive Radar Coverage for Cars Detection in Semi-Urban Scenarios

Authors: Pedro Gómez-del-Hoyo, Jose-Luis Bárcena-Humanes, Nerea del-Rey-Maestre, María-Pilar Jarabo-Amores, David Mata-Moya

Abstract:

A study of achievable coverages using passive radar systems in terrestrial traffic monitoring applications is presented. The study includes the estimation of the bistatic radar cross section of different commercial vehicle models that provide challenging low values which make detection really difficult. A semi-urban scenario is selected to evaluate the impact of excess propagation losses generated by an irregular relief. A bistatic passive radar exploiting UHF frequencies radiated by digital video broadcasting transmitters is assumed. A general method of coverage estimation using electromagnetic simulators in combination with estimated car average bistatic radar cross section is applied. In order to reduce the computational cost, hybrid solution is implemented, assuming free space for the target-receiver path but estimating the excess propagation losses for the transmitter-target one.

Keywords: Bistatic radar cross section, passive radar, propagation losses, radar coverage.

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1329 Characterization and Detection of Cadmium Ion Using Modification Calixarene with Multiwalled Carbon Nanotubes

Authors: Amira Shakila Razali, Faridah Lisa Supian, Muhammad Mat Salleh, Suraini Abu Bakar

Abstract:

Water contamination by toxic compound is one of the serious environmental problems today. These toxic compounds mostly originated from industrial effluents, agriculture, natural sources and human waste. These studies focus on modification of multiwalled carbon nanotube (MWCNTs) with nanoparticle of calixarene and explore the possibility of using this modification for the remediation of cadmium in water. The nanocomposites were prepared by dissolving calixarene in chloroform solution as solvent, followed by additional multiwalled carbon nanotube (MWCNTs) then sonication process for 3 hour and fabricated the nanocomposites on substrate by spin coating method. Finally, the nanocomposites were tested on cadmium ion (10 mg/ml). The morphology of nanocomposites was investigated by FESEM showing the formation of calixarene on the outer walls of carbon nanotube and cadmium ion also clearly seen from the micrograph. This formation was supported by using energy dispersive x-ray (EDX). The presence of cadmium ions in the films, leads to some changes in the surface potential and Fourier Transform Infrared spectroscopy (FTIR).The nanocomposites MWCNTs-calixarene have potential for development of sensor for pollutant monitoring and nanoelectronics devices applications.

Keywords: Calixarene, Multiwalled Carbon Nanotubes, Cadmium, Surface Potential.

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1328 Influence of p-y curves on Buckling Capacity of Pile Foundation

Authors: Praveen Huded M., Suresh R. Dash

Abstract:

Pile foundations are one of the most preferred deep foundation systems for high rise or heavily loaded structures. In many instances, the failure of the pile founded structures in liquefiable soils had been observed even in many recent earthquakes. Failure of pile foundation have occurred because of buckling, as the pile behaves as an unsupported slender structural element once the surrounding soil liquefies. However, the buckling capacity depends on the depth of soil liquefied and its residual strength. Hence it is essential to check the pile against the possible buckling failure. Beam on non-linear Winkler Foundation is one of the efficient methods to model the pile-soil behavior in liquefiable soil. The pile-soil interaction is modelled through p-y springs, there are different p-y curves available for modeling liquefiable soil. In the present work, the influence of two such p-y curves on the buckling capacity of pile foundation is studied considering the initial geometric and non-linear behavior of pile foundation. The proposed method is validated against experimental results. A significant difference in the buckling capacity is observed for the two p-y curves used in the analysis. A parametric study is conducted to understand the influence of pile flexural rigidity, different initial geometric imperfections, and different soil relative densities on the buckling capacity of pile foundation.

Keywords: pile foundation, liquefaction, buckling load, non-linear p-y curve

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1327 A Study on Removal Characteristics of (Mn2+) from Aqueous Solution by CNT

Authors: Nassereldeen A. Kabashi, Suleyman A. Muyibi. Mohammed E. Saeed., Farhana I. Yahya

Abstract:

It is important to remove manganese from water because of its effects on human and the environment. Human activities are one of the biggest contributors for excessive manganese concentration in the environment. The proposed method to remove manganese in aqueous solution by using adsorption as in carbon nanotubes (CNT) at different parameters: The parameters are CNT dosage, pH, agitation speed and contact time. Different pHs are pH 6.0, pH 6.5, pH 7.0, pH 7.5 and pH 8.0, CNT dosages are 5mg, 6.25mg, 7.5mg, 8.75mg or 10mg, contact time are 10 min, 32.5 min, 55 min, 87.5 min and 120 min while the agitation speeds are 100rpm, 150rpm, 200rpm, 250rpm and 300rpm. The parameters chosen for experiments are based on experimental design done by using Central Composite Design, Design Expert 6.0 with 4 parameters, 5 levels and 2 replications. Based on the results, condition set at pH 7.0, agitation speed of 300 rpm, 7.5mg and contact time 55 minutes gives the highest removal with 75.5%. From ANOVA analysis in Design Expert 6.0, the residual concentration will be very much affected by pH and CNT dosage. Initial manganese concentration is 1.2mg/L while the lowest residual concentration achieved is 0.294mg/L, which almost satisfy DOE Malaysia Standard B requirement. Therefore, further experiments must be done to remove manganese from model water to the required standard (0.2 mg/L) with the initial concentration set to 0.294 mg/L.

Keywords: Adsorption, CNT, DOE, Manganese, Parameters.

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1326 Non-parametric Linear Technique for Measuring the Efficiency of Winter Road Maintenance in the Arctic Area

Authors: Mahshid Hatamzad, Geanette Polanco

Abstract:

Improving the performance of Winter Road Maintenance (WRM) can increase the traffic safety and reduce the cost as well as environmental impacts. This study evaluates the efficiency of WRM technique, named salting, in the Arctic area by using Data Envelopment Analysis (DEA), which is a non-parametric linear method to measure the efficiencies of decision-making units (DMUs) based on handling multiple inputs and multiple outputs at the same time that their associated weights are not known. Here, roads are considered as DMUs for which the efficiency must be determined. The three input variables considered are traffic flow, road area and WRM cost. In addition, the two output variables included are level of safety in the roads and environment impacts resulted from WRM, which is also considered as an uncontrollable factor in the second scenario. The results show the performance of DMUs from the most efficient WRM to the inefficient/least efficient one and this information provides decision makers with technical support and the required suggested improvements for inefficient WRM, in order to achieve a cost-effective WRM and a safe road transportation during wintertime in the Arctic areas.

Keywords: DEA, environmental impacts, risk and safety, WRM.

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1325 Study on Influencing Factors of Walkability of Rail Transit Station Area

Authors: Yang Wenjuan, Xu Yilun

Abstract:

Based on the comparative analysis of the relevant evaluation methods of walking environment, this paper selects the combined evaluation method of macro urban morphology analysis and micro urban design quality survey, then investigates and analyzes the walking environment of three rail transit station area in Nanjing to explore the influence factor and internal relation of walkability of rail transit station area. Analysis shows that micro urban design factors have greater impact on the walkability of rail transit station area compared with macro urban morphology factors, the convenience is the key factor in the four aspects of convenience, security, identity and comfortability of the urban design factors, the convenience is not only affected by the block network form, but also related to the quality of the street space. The overall evaluation of walkability comes from the overlapping and regrouping of the walking environment at different levels, but some environmental factors play a leading role. The social attributes of pedestrians also partly influence their walking perception and evaluation.

Keywords: Rail transit station area, walkability, evaluation, influence factors.

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1324 Selection of Photovoltaic Solar Power Plant Investment Projects - An ANP Approach

Authors: P. Aragonés-Beltrán, F. Chaparro-González, J. P. Pastor Ferrando, M. García-Melón

Abstract:

In this paper the Analytic Network Process (ANP) is applied to the selection of photovoltaic (PV) solar power projects. These projects follow a long management and execution process from plant site selection to plant start-up. As a consequence, there are many risks of time delays and even of project stoppage. In the case study presented in this paper a top manager of an important Spanish company that operates in the power market has to decide on the best PV project (from four alternative projects) to invest based on risk minimization. The manager identified 50 project execution delay and/or stoppage risks. The influences among elements of the network (groups of risks and alternatives) were identified and analyzed using the ANP multicriteria decision analysis method. After analyzing the results the main conclusion is that the network model can manage all the information of the real-world problem and thus it is a decision analysis model recommended by the authors. The strengths and weaknesses ANP as a multicriteria decision analysis tool are also described in the paper.

Keywords: Multicriteria decision analysis, Analytic Network Process, Photovoltaic solar power projects.

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1323 Thermodynamic Analysis of a Vapor Absorption System Using Modified Gouy-Stodola Equation

Authors: Gulshan Sachdeva, Ram Bilash

Abstract:

In this paper, the exergy analysis of vapor absorption refrigeration system using LiBr-H2O as working fluid is carried out with the modified Gouy-Stodola approach rather than the classical Gouy-Stodola equation and effect of varying input parameters is also studied on the performance of the system. As the modified approach uses the concept of effective temperature, the mathematical expressions for effective temperature have been formulated and calculated for each component of the system. Various constraints and equations are used to develop program in EES to solve these equations. The main aim of this analysis is to determine the performance of the system and the components having major irreversible loss. Results show that exergy destruction rate is considerable in absorber and generator followed by evaporator and condenser. There is an increase in exergy destruction in generator, absorber and condenser and decrease in the evaporator by the modified approach as compared to the conventional approach. The value of exergy determined by the modified Gouy-Stodola equation deviates maximum i.e. 26% in the generator as compared to the exergy calculated by the classical Gouy-Stodola method.

Keywords: Exergy analysis, Gouy-Stodola, refrigeration, vapor absorption.

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1322 CAD Model of Cole Cole Representation for Analyzing Performance of Microstrip Moisture Sensing Applications

Authors: Settapong Malisuwan, Jesada Sivaraks, Wasan Jaiwong, Veerapat Sanpanich

Abstract:

In the past decade, the development of microstrip sensor application has evolved tremendously. Although cut and trial method was adopted to develop microstrip sensing applications in the past, Computer-Aided-Design (CAD) is a more effective as it ensures less time is consumed and cost saving is achieved in developing microstrip sensing applications. Therefore microstrip sensing applications has gained popularity as an effective tool adopted in continuous sensing of moisture content particularly in products that is administered mainly by liquid content. In this research, the Cole-Cole representation of reactive relaxation is applied to assess the performance of the microstrip sensor devices. The microstrip sensor application is an effective tool suitable for sensing the moisture content of dielectric material. Analogous to dielectric relaxation consideration of Cole-Cole diagrams as applied to dielectric materials, a “reactive relaxation concept” concept is introduced to represent the frequency-dependent and moisture content characteristics of microstrip sensor devices.

Keywords: Microstrip, Sensor, Cole-Cole Representation, Moisture content.

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1321 An Improved Fast Video Clip Search Algorithm for Copy Detection using Histogram-based Features

Authors: Feifei Lee, Qiu Chen, Koji Kotani, Tadahiro Ohmi

Abstract:

In this paper, we present an improved fast and robust search algorithm for copy detection using histogram-based features for short MPEG video clips from large video database. There are two types of histogram features used to generate more robust features. The first one is based on the adjacent pixel intensity difference quantization (APIDQ) algorithm, which had been reliably applied to human face recognition previously. An APIDQ histogram is utilized as the feature vector of the frame image. Another one is ordinal histogram feature which is robust to color distortion. Furthermore, by Combining with a temporal division method, the spatial and temporal features of the video sequence are integrated to realize fast and robust video search for copy detection. Experimental results show the proposed algorithm can detect the similar video clip more accurately and robust than conventional fast video search algorithm.

Keywords: Fast search, Copy detection, Adjacent pixel intensity difference quantization (APIDQ), DC image, Histogram feature.

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1320 Digital Encoder Based Power Frequency Deviation Measurement

Authors: Syed Javed Arif, Mohd Ayyub Khan, Saleem Anwar Khan

Abstract:

In this paper, a simple method is presented for measurement of power frequency deviations. A phase locked loop (PLL) is used to multiply the signal under test by a factor of 100. The number of pulses in this pulse train signal is counted over a stable known period, using decade driving assemblies (DDAs) and flip-flops. These signals are combined using logic gates and then passed through decade counters to give a unique combination of pulses or levels, which are further encoded. These pulses are equally suitable for both control applications and display units. The experimental circuit developed gives a resolution of 1 Hz within the measurement period of 20 ms. The proposed circuit is also simulated in Verilog Hardware Description Language (VHDL) and implemented using Field Programing Gate Arrays (FPGAs). A Mixed signal Oscilloscope (MSO) is used to observe the results of FPGA implementation. These results are compared with the results of the proposed circuit of discrete components. The proposed system is useful for frequency deviation measurement and control in power systems.

Keywords: Frequency measurement, digital control, phase locked loop, encoding, Verilog HDL.

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1319 Modeling of Pulping of Sugar Maple Using Advanced Neural Network Learning

Authors: W. D. Wan Rosli, Z. Zainuddin, R. Lanouette, S. Sathasivam

Abstract:

This paper reports work done to improve the modeling of complex processes when only small experimental data sets are available. Neural networks are used to capture the nonlinear underlying phenomena contained in the data set and to partly eliminate the burden of having to specify completely the structure of the model. Two different types of neural networks were used for the application of Pulping of Sugar Maple problem. A three layer feed forward neural networks, using the Preconditioned Conjugate Gradient (PCG) methods were used in this investigation. Preconditioning is a method to improve convergence by lowering the condition number and increasing the eigenvalues clustering. The idea is to solve the modified problem where M is a positive-definite preconditioner that is closely related to A. We mainly focused on Preconditioned Conjugate Gradient- based training methods which originated from optimization theory, namely Preconditioned Conjugate Gradient with Fletcher-Reeves Update (PCGF), Preconditioned Conjugate Gradient with Polak-Ribiere Update (PCGP) and Preconditioned Conjugate Gradient with Powell-Beale Restarts (PCGB). The behavior of the PCG methods in the simulations proved to be robust against phenomenon such as oscillations due to large step size.

Keywords: Convergence, Modeling, Neural Networks, Preconditioned Conjugate Gradient.

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1318 Side Effects of Dental Tooth Whitening: Data from Literature

Authors: Saimir Heta, Ilma Robo, Emela Dalloshi, Nevila Alliu, Vera Ostreni

Abstract:

The dental whitening process, beyond the fact that it is a mini-invasive dental treatment, has effects on the dental structure or on the pulp of the tooth where it is applied. The electronic search was performed using keywords to find articles published within the last 10 years about side effects, assessed as such, of the minimally invasive dental bleaching treatment. The aim of the study was to evaluate the side effects of bleaching based on the percentage and type of solution used, where the latter was evaluated on the basic solution used for bleaching. The side effects of bleaching are evaluated in selected articles depending on the method of bleaching application, which means it is carried out with recommended solutions, or with mixtures of alternative solutions or substances based on Internet information. The dental bleaching process has side effects which have not yet been definitively evaluated, experimentally in large samples of individuals or animals (mice or cattle) to arrive at accurate numerical conclusions. The trend of publications about this topic is increasing in recent years, as long as the trend for aesthetic facial treatments, including dental ones, is increasing.

Keywords: Teeth whitening, side effects, permanent teeth, formed dental apex.

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1317 Mannequin Evaluation of 3D-Printed Intermittent Oro-Esophageal Tube Guide for Dysphagia

Authors: Yujin Jeong, Youkyung Son, Myounghwan Choi, Sanghyub Lee, Sangyeol Lee, Changho Hwang, Kyo-in Koo

Abstract:

Dysphasia is difficulty in swallowing food because of oral cavity impairments induced by stroke, muscle damage, tumor. Intermittent oro-esophageal (IOE) tube feeding is one of the well-known feeding methods for the dysphasia patients. However, it is hard to insert at the proper position in esophagus. In this study, we design and fabricate the IOE tube guide using 3-dimensional (3D) printer. The printed IOE tube is tested in a mannequin (Airway Management Trainer, Co., Ltd., Copenhagen, Denmark) mimicking human’s esophagus. The gag reflex point is measured as the design point in the mannequin. To avoid the gag reflex, we design various shapes of IOE tube guide. One structure is separated into three parts; biting part, part through oral cavity, connecting part to oro-esophageal. We designed 6 types of IOE tube guide adjusting length and angle of these three parts. To evaluate the IOE tube guide, it is inserted in the mannequin, and through the inserted guide, an endoscopic camera successfully arrived at the oro-esophageal. We had planned to apply this mannequin-based design experience to patients in near future.

Keywords: Dysphagia, feeding method, IOE tube guide, 3-D printer.

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1316 Automatic Translation of Ada-ECATNet Using Rewriting Logic

Authors: N. Boudiaf

Abstract:

One major difficulty that faces developers of concurrent and distributed software is analysis for concurrency based faults like deadlocks. Petri nets are used extensively in the verification of correctness of concurrent programs. ECATNets are a category of algebraic Petri nets based on a sound combination of algebraic abstract types and high-level Petri nets. ECATNets have 'sound' and 'complete' semantics because of their integration in rewriting logic and its programming language Maude. Rewriting logic is considered as one of very powerful logics in terms of description, verification and programming of concurrent systems We proposed previously a method for translating Ada-95 tasking programs to ECATNets formalism (Ada-ECATNet) and we showed that ECATNets formalism provides a more compact translation for Ada programs compared to the other approaches based on simple Petri nets or Colored Petri nets. We showed also previously how the ECATNet formalism offers to Ada many validation and verification tools like simulation, Model Checking, accessibility analysis and static analysis. In this paper, we describe the implementation of our translation of the Ada programs into ECATNets.

Keywords: Ada tasking, Analysis, Automatic Translation, ECATNets, Maude, Rewriting Logic.

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1315 Semi-Automatic Analyzer to Detect Authorial Intentions in Scientific Documents

Authors: Kanso Hassan, Elhore Ali, Soule-dupuy Chantal, Tazi Said

Abstract:

Information Retrieval has the objective of studying models and the realization of systems allowing a user to find the relevant documents adapted to his need of information. The information search is a problem which remains difficult because the difficulty in the representing and to treat the natural languages such as polysemia. Intentional Structures promise to be a new paradigm to extend the existing documents structures and to enhance the different phases of documents process such as creation, editing, search and retrieval. The intention recognition of the author-s of texts can reduce the largeness of this problem. In this article, we present intentions recognition system is based on a semi-automatic method of extraction the intentional information starting from a corpus of text. This system is also able to update the ontology of intentions for the enrichment of the knowledge base containing all possible intentions of a domain. This approach uses the construction of a semi-formal ontology which considered as the conceptualization of the intentional information contained in a text. An experiments on scientific publications in the field of computer science was considered to validate this approach.

Keywords: Information research, text analyzes, intentionalstructure, segmentation, ontology, natural language processing.

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1314 Barrier Properties of Starch - Ethylene Vinyl Alcohol Nanocomposites

Authors: Farid Amidi-Fazli, Neda Amidi-Fazli

Abstract:

Replacement of plastics used in the food industry seems to be a serious issue to overcome mainly the environmental problems in recent years. This study investigates the hydrophilicity and permeability properties of starch biopolymer which ethylene vinyl alcohol (EVOH) (0-10%) and nanocrystalline cellulose (NCC) (1-15%) were used to enhance its properties. Starch -EVOH nanocomposites were prepared by casting method in different formulations. NCC production by acid hydrolysis was confirmed by scanning electron microscopy. Solubility, water vapor permeability, water vapor transmission rate and moisture absorbance were measured on each of the nanocomposites. The results were analyzed by SAS software. The lowest moisture absorbance was measured in pure starch nanocomposite containing 8% NCC. The lowest permeability to water vapor belongs to starch nanocomposite containing 8% NCC and the sample containing 7.8% EVOH and 13% NCC. Also the lowest solubility was observed in the composite contains the highest amount of EVOH. Applied Process resulted in production of bio films which have good resistance to water vapor permeability and solubility in water. The use of NCC and EVOH leads to reduced moisture absorbance property of the biofilms.

Keywords: Starch, EVOH, nanocrystalline cellulose, Hydrophilicity.

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1313 Investigation of Passive Solutions of Thermal Comfort in Housing Aiming to Reduce Energy Consumption

Authors: Josiane R. Pires, Marco A. S. González, Bruna L. Brenner, Luciana S. Roos

Abstract:

The concern with sustainability brought the need for optimization of the buildings to reduce consumption of natural resources. Almost 1/3 of energy demanded by Brazilian housings is used to provide thermal solutions. AEC sector may contribute applying bioclimatic strategies on building design. The aim of this research is to investigate the viability of applying some alternative solutions in residential buildings. The research was developed with computational simulation on single family social housing, examining envelope type, absorptance, and insolation. The analysis of the thermal performance applied both Brazilian standard NBR 15575 and degree-hour method, in the scenery of Porto Alegre, a southern Brazilian city. We used BIM modeling through Revit/Autodesk and used Energy Plus to thermal simulation. The payback of the investment was calculated comparing energy savings and building costs, in a period of 50 years. The results shown that with the increment of envelope’s insulation there is thermal comfort improvement and energy economy, with a pay-back period of 24 to 36 years, in some cases.

Keywords: Civil construction, design, thermal performance, energy, economic analysis.

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1312 A DMB-TCA Simulation Method for On-Road Traffic Travel Demand Impact Analysis

Authors: Zundong Zhang, Limin Jia, Zhao Tian, Yanfang Yang

Abstract:

Travel Demands influence micro-level traffic behavior, furthermore traffic states. In order to evaluate the effect of travel demands on traffic states, this paper introduces the Demand- Motivation-Behaviors (DMB) micro traffic behavior analysis model which denotes that vehicles behaviors are determines by motivations that relies on traffic demands from the perspective of behavior science. For vehicles, there are two kinds of travel demands: reaching travel destinations from orientations and meeting expectations of travel speed. To satisfy travel demands, the micro traffic behaviors are delivered such as car following behavior, optional and mandatory lane changing behaviors. Especially, mandatory lane changing behaviors depending on travel demands take strong impact on traffic states. In this paper, we define the DMB-based cellular automate traffic simulation model to evaluate the effect of travel demands on traffic states under the different δ values that reflect the ratio of mandatory lane-change vehicles.

Keywords: Demand-Motivation-Behavior, Mandatory Lane Changing, Traffic Cellular Automata.

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1311 Synthesis and Characterization of Nickel and Sulphur Sensitized Zinc Oxide Structures

Authors: Ella C. Linganiso, Bonex W. Mwakikunga, Trilock Singh, Sanjay Mathur, Odireleng M. Ntwaeaborwa

Abstract:

The use of nanostructured semiconducting material to catalyze degradation of environmental pollutants still receives much attention to date. One of the desired characteristics for pollutant degradation under ultra-violet visible light is the materials with extended carrier charge separation that allows for electronic transfer between the catalyst and the pollutants. In this work, zinc oxide n-type semiconductor vertically aligned structures were fabricated on silicon (100) substrates using the chemical bath deposition method. The as-synthesized structures were treated with nickel and sulphur. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy were used to characterize the phase purity, structural dimensions and elemental composition of the obtained structures respectively. Photoluminescence emission measurements showed a decrease in both the near band edge emission as well as the defect band emission upon addition of nickel and sulphur with different concentrations. This was attributed to increased charger-carrier-separation due to the presence of Ni-S material on ZnO surface, which is linked to improved charge transfer during photocatalytic reactions.

Keywords: Carrier-charge-separation, nickel, sulphur, zinc oxide, photoluminescence.

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1310 Synthetic Aperture Radar Remote Sensing Classification Using the Bag of Visual Words Model to Land Cover Studies

Authors: Reza Mohammadi, Mahmod R. Sahebi, Mehrnoosh Omati, Milad Vahidi

Abstract:

Classification of high resolution polarimetric Synthetic Aperture Radar (PolSAR) images plays an important role in land cover and land use management. Recently, classification algorithms based on Bag of Visual Words (BOVW) model have attracted significant interest among scholars and researchers in and out of the field of remote sensing. In this paper, BOVW model with pixel based low-level features has been implemented to classify a subset of San Francisco bay PolSAR image, acquired by RADARSAR 2 in C-band. We have used segment-based decision-making strategy and compared the result with the result of traditional Support Vector Machine (SVM) classifier. 90.95% overall accuracy of the classification with the proposed algorithm has shown that the proposed algorithm is comparable with the state-of-the-art methods. In addition to increase in the classification accuracy, the proposed method has decreased undesirable speckle effect of SAR images.

Keywords: Bag of Visual Words, classification, feature extraction, land cover management, Polarimetric Synthetic Aperture Radar.

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1309 A Robust Extrapolation Method for Curtailed Aperture Reconstruction in Acoustic Imaging

Authors: R. Bremananth

Abstract:

Acoustic Imaging based sound localization using microphone array is a challenging task in digital-signal processing. Discrete Fourier transform (DFT) based near-field acoustical holography (NAH) is an important acoustical technique for sound source localization and provide an efficient solution to the ill-posed problem. However, in practice, due to the usage of small curtailed aperture and its consequence of significant spectral leakage, the DFT could not reconstruct the active-region-of-sound (AROS) effectively, especially near the edges of aperture. In this paper, we emphasize the fundamental problems of DFT-based NAH, provide a solution to spectral leakage effect by the extrapolation based on linear predictive coding and 2D Tukey windowing. This approach has been tested to localize the single and multi-point sound sources. We observe that incorporating extrapolation technique increases the spatial resolution, localization accuracy and reduces spectral leakage when small curtail aperture with a lower number of sensors accounts.

Keywords: Acoustic Imaging, Discrete Fourier Transform (DFT), k-space wavenumber, Near-Field Acoustical Holography (NAH), Source Localization, Spectral Leakage.

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1308 Statistical Optimization of Medium Components for Biomass Production of Chlorella pyrenoidosa under Autotrophic Conditions and Evaluation of Its Biochemical Composition under Stress Conditions

Authors: N. P. Dhull, K. Gupta, R. Soni, D. K. Rahi, S. K. Soni

Abstract:

The aim of the present work was to statistically design an autotrophic medium for maximum biomass production by Chlorella pyrenoidosa using response surface methodology. After evaluating one factor at a time approach, K2HPO4, KNO3, MgSO4.7H2O and NaHCO3 were preferred over the other components of the fog’s medium as most critical autotrophic medium components. The study showed that the maximum biomass yield was achieved while the concentrations of MgSO4.7H2O, K2HPO4, KNO3 and NaHCO3 were 0.409 g/L, 0.24 g/L, 1.033 g/L, and 3.265 g/L, respectively. The study reported that the biomass productivity of C. pyrenoidosa improved from 0.14 g/L in defined fog’s medium to 1.40 g/L in modified fog’s medium resulting 10 fold increase. The biochemical composition biosynthesis of C. pyrenoidosa was altered using nitrogen limiting stress bringing about 5.23 fold increase in lipid content than control (cell without stress), as analyzed by FTIR integration method.

Keywords: Autotrophic condition, Chlorella pyrenoidosa, FTIR, Response Surface Methodology, Optimization.

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1307 The Comparative Investigation and Calculation of Thermo-Neutronic Parameters on Two Gens II and III Nuclear Reactors with Same Powers

Authors: Mousavi Shirazi, Seyed Alireza, Rastayesh, Sima

Abstract:

Whereas in the third generation nuclear reactors, dimensions of core and also the kind of coolant and enrichment percent of fuel have significantly changed than the second generation, therefore in this article the aim is based on a comparative investigation between two same power reactors of second and third generations, that the neutronic parameters of both reactors such as: K∞, Keff and its details and thermal hydraulic parameters such as: power density, specific power, volumetric heat rate, released power per fuel volume unit, volume and mass of clad and fuel (consisting fissile and fertile fuels), be calculated and compared together. By this comparing the efficiency and modification of third generation nuclear reactors than second generation which have same power can be distinguished. In order to calculate the cited parameters, some information such as: core dimensions, the pitch of lattice, the fuel matter, the percent of enrichment and the kind of coolant are used. For calculating the neutronic parameters, a neutronic program entitled: SIXFAC and also related formulas have been used. Meantime for calculating the thermal hydraulic and other parameters, analytical method and related formulas have been applied.

Keywords: Nuclear reactor, second generation, third generation, thermo-neutronics parameters.

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1306 Effects of Operating Conditions on Calcium Carbonate Fouling in a Plate Heat Exchanger

Authors: K. Pana-Suppamassadu, P. Jeimrittiwong, P. Narataruksa, S. Tungkamani

Abstract:

The aim of this work is to investigate on the internalflow patterns in a plate heat exchanger channel, which affect the rate of sedimentation fouling on the heat transfer surface of the plate heat exchanger. The research methodologies were the computer simulation using Computational Fluid Dynamics (CFD) and the experimental works. COMSOL MULTIPHYSICS™ Version 3.3 was used to simulate the velocity flow fields to verify the low and high flow regions. The results from the CFD technique were then compared with the images obtained from the experiments in which the fouling test rig was set up with a singlechannel plate heat exchanger to monitor the fouling of calcium carbonate. Two parameters were varied i.e., the crossing angle of the two plate: 55/55, 10/10, and 55/10 degree, and the fluid flow rate at the inlet: 0.0566, 0.1132 and 0.1698 m/s. The type of plate “GX-12" (the surface area 0.12 m2, the depth 2.9 mm, the width of fluid flow 215 mm and the thickness of stainless plate of 0.5 mm) was used in this study. The results indicated that the velocity distribution for the case of 55/55 degree seems to be very well organized when compared with the others. Also, an increase in the inlet velocity resulted in the reduction of fouling rate on the surface of plate heat exchangers.

Keywords: Computational fluid dynamics, crossing angles, finite element method, plate heat exchanger.

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1305 Development of Accident Predictive Model for Rural Roadway

Authors: Fajaruddin Mustakim, Motohiro Fujita

Abstract:

This paper present the study carried out of accident analysis, black spot study and to develop accident predictive models based on the data collected at rural roadway, Federal Route 50 (F050) Malaysia. The road accident trends and black spot ranking were established on the F050. The development of the accident prediction model will concentrate in Parit Raja area from KM 19 to KM 23. Multiple non-linear regression method was used to relate the discrete accident data with the road and traffic flow explanatory variable. The dependent variable was modeled as the number of crashes namely accident point weighting, however accident point weighting have rarely been account in the road accident prediction Models. The result show that, the existing number of major access points, without traffic light, rise in speed, increasing number of Annual Average Daily Traffic (AADT), growing number of motorcycle and motorcar and reducing the time gap are the potential contributors of increment accident rates on multiple rural roadway.

Keywords: Accident Trends, Black Spot Study, Accident Prediction Model

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1304 Some Investigations on Higher Mathematics Scores for Chinese University Student

Authors: Xun Ge, Jingju Qian

Abstract:

To investigate some relations between higher mathe¬matics scores in Chinese graduate student entrance examination and calculus (resp. linear algebra, probability statistics) scores in subject's completion examination of Chinese university, we select 20 students as a sample, take higher mathematics score as a decision attribute and take calculus score, linear algebra score, probability statistics score as condition attributes. In this paper, we are based on rough-set theory (Rough-set theory is a logic-mathematical method proposed by Z. Pawlak. In recent years, this theory has been widely implemented in the many fields of natural science and societal science.) to investigate importance of condition attributes with respective to decision attribute and strength of condition attributes supporting decision attribute. Results of this investigation will be helpful for university students to raise higher mathematics scores in Chinese graduate student entrance examination.

Keywords: Rough set, higher mathematics scores, decision attribute, condition attribute.

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1303 An Exploratory Study of the Student’s Learning Experience by Applying Different Tools for e-Learning and e-Teaching

Authors: Angel Daniel Muñoz Guzmán

Abstract:

E-learning is becoming more and more common every day. For online, hybrid or traditional face-to-face programs, there are some e-teaching platforms like Google classroom, Blackboard, Moodle and Canvas, and there are platforms for full e-learning like Coursera, edX or Udemy. These tools are changing the way students acquire knowledge at schools; however, in today’s changing world that is not enough. As students’ needs and skills change and become more complex, new tools will need to be added to keep them engaged and potentialize their learning. This is especially important in the current global situation that is changing everything: the Covid-19 pandemic. Due to Covid-19, education had to make an unexpected switch from face-to-face courses to digital courses. In this study, the students’ learning experience is analyzed by applying different e-tools and following the Tec21 Model and a flexible and digital model, both developed by the Tecnologico de Monterrey University. The evaluation of the students’ learning experience has been made by the quantitative PrEmo method of emotions. Findings suggest that the quantity of e-tools used during a course does not affect the students’ learning experience as much as how a teacher links every available tool and makes them work as one in order to keep the student engaged and motivated.

Keywords: Student, experience, e-learning, e-teaching, e-tools, technology, education.

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1302 Optimization of Pretreatment and Enzymatic Saccharification of Cogon Grass Prior Ethanol Production

Authors: Jhalique Jane R. Fojas, Ernesto J. Del Rosario

Abstract:

The dilute acid pretreatment and enzymatic saccharification of lignocellulosic substrate, cogon grass (Imperata cylindrical, L.) was optimized prior ethanol fermentation using simultaneous saccharification and fermentation (SSF) method. The optimum pretreatment conditions, temperature, sulfuric acid concentration, and reaction time were evaluated by determining the maximum sugar yield at constant enzyme loading. Cogon grass, at 10% w/v substrate loading, has optimum pretreatment conditions of 126°C, 0.6% v/v H2SO4, and 20min reaction time. These pretreatment conditions were used to optimize enzymatic saccharification using different enzyme combinations. The maximum saccharification yield of 36.68mg/mL (71.29% reducing sugar) was obtained using 25FPU/g-cellulose cellulase complex combined with 1.1% w/w of cellobiase, ß-glucosidase, and 0.225% w/w of hemicellulase complex, after 96 hours of saccharification. Using the optimum pretreatment and saccharification conditions, SSF of treated substrates was done at 37°C for 120 hours using industrial yeast strain HBY3, Saccharomyces cerevisiae. The ethanol yield for cogon grass at 4% w/w loading was 9.11g/L with 5.74mg/mL total residual sugar.

Keywords: Acid pretreatment, bioethanol, biomass, cogon grass, fermentation, lignocellylose, SSF.

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1301 Application of Relative Regional Total Energy in Rotary Drums with Axial Segregation Characteristics

Authors: Qiuhua Miao, Peng Huang, Yifei Ding

Abstract:

Particles with different properties tend to be unevenly distributed along an axial direction of the rotating drum, which is usually ignored. Therefore, it is important to study the relationship between axial segregation characteristics and particle crushing efficiency in longer drums. In this paper, a relative area total energy (RRTE) index is proposed, which aims to evaluate the overall crushing energy distribution characteristics. Based on numerical simulation verification, the proposed RRTE index can reflect the overall grinding effect more comprehensively, clearly representing crushing energy distribution in different drum areas. Furthermore, the proposed method is applied to the relation between axial segregation and crushing energy in drums. Compared with the radial section, the collision loss energy of the axial section can better reflect the overall crushing effect in long drums. The axial segregation characteristics directly affect the total energy distribution between medium and abrasive, reducing overall crushing efficiency. Therefore, the axial segregation characteristics should be avoided as much as possible in the crushing of the long rotary drum.

Keywords: Relative regional total energy, crushing energy, axial segregation characteristics, rotary drum.

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