Search results for: hollow profiles
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 460

Search results for: hollow profiles

220 The Crack Propagation on Glass in Laser Thermal Cleavage

Authors: Jehnming Lin

Abstract:

In the laser cleavage of glass, the laser is mostly adopted as a heat source to generate a thermal stress state on the substrates. The crack propagation of the soda-lime glass in the laser thermal cleavage with the straight-turning paths was investigated in this study experimentally and numerically. The crack propagation was visualized by a high speed camera with the off-line examination on the micro-crack propagation. The temperature and stress distributions induced by the laser heat source were calculated by ANSYS software based on the finite element method (FEM). With the cutting paths in various turning directions, the experimental and numerical results were in comparison and verified. The fracture modes due to the normal and shear stresses were verified at the turning point of the laser cleavage path. It shows a significant variation of the stress profiles along the straight-turning paths and causes a change on the fracture modes.

Keywords: Laser cleavage, glass, fracture, stress analysis.

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219 Isolation and Probiotic Characterization of Arsenic-Resistant Lactic Acid Bacteria for Uptaking Arsenic

Authors: Jatindra N. Bhakta, Kouhei Ohnishi, Yukihiro Munekage, Kozo Iwasaki

Abstract:

The growing health hazardous impact of arsenic (As) contamination in environment is the impetus of the present investigation. Application of lactic acid bacteria (LAB) for the removal of toxic and heavy metals from water has been reported. This study was performed in order to isolate and characterize the Asresistant LAB from mud and sludge samples for using as efficient As uptaking probiotic. Isolation of As-resistant LAB colonies was performed by spread plate technique using bromocresol purple impregnated-MRS (BP-MRS) agar media provided with As @ 50 μg/ml. Isolated LAB were employed for probiotic characterization process, acid and bile tolerance, lactic acid production, antibacterial activity and antibiotic tolerance assays. After As-resistant and removal characterizations, the LAB were identified using 16S rDNA sequencing. A total of 103 isolates were identified as As-resistant strains of LAB. The survival of 6 strains (As99-1, As100-2, As101-3, As102-4, As105-7, and As112-9) was found after passing through the sequential probiotic characterizations. Resistant pattern pronounced hollow zones at As concentration >2000 μg/ml in As99-1, As100-2, and As101-3 LAB strains, whereas it was found at ~1000 μg/ml in rest 3 strains. Among 6 strains, the As uptake efficiency of As102-4 (0.006 μg/h/mg wet weight of cell) was higher (17 – 209%) compared to remaining LAB. 16S rDNA sequencing data of 3 (As99- 1, As100-2, and As101-3) and 3 (As102-4, As105-7, and As112-9) LAB strains clearly showed 97 to 99% (340 bp) homology to Pediococcus dextrinicus and Pediococcus acidilactici, respectively. Though, there was no correlation between the metal resistant and removal efficiency of LAB examined but identified elevated As removing LAB would probably be a potential As uptaking probiotic agent. Since present experiment concerned with only As removal from pure water, As removal and removal mechanism in natural condition of intestinal milieu should be assessed in future studies.

Keywords: Lactic acid bacteria, As-resistant, characterization, Pediococcus sp., As removal probiotic.

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218 Gene Selection Guided by Feature Interdependence

Authors: Hung-Ming Lai, Andreas Albrecht, Kathleen Steinhöfel

Abstract:

Cancers could normally be marked by a number of differentially expressed genes which show enormous potential as biomarkers for a certain disease. Recent years, cancer classification based on the investigation of gene expression profiles derived by high-throughput microarrays has widely been used. The selection of discriminative genes is, therefore, an essential preprocess step in carcinogenesis studies. In this paper, we have proposed a novel gene selector using information-theoretic measures for biological discovery. This multivariate filter is a four-stage framework through the analyses of feature relevance, feature interdependence, feature redundancy-dependence and subset rankings, and having been examined on the colon cancer data set. Our experimental result show that the proposed method outperformed other information theorem based filters in all aspect of classification errors and classification performance.

Keywords: Colon cancer, feature interdependence, feature subset selection, gene selection, microarray data analysis.

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217 Modeling of Gas Turbine Cooled Blades

Authors: A. Pashayev, D. Askerov, R. Sadiqov, A. Samedov, C. Ardil

Abstract:

In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and quasi-stationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine first stage nozzle blade.

Keywords: Gas turbine, cooled blade, nozzle blade, temperature field.

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216 Personalization and the Universal Communications Identifier Concept

Authors: Françoise Petersen, Mike Pluke, Tatiana Kovacikova, Giovanni Bartolomeo

Abstract:

As communications systems and technology become more advanced and complex, it will be increasingly important to focus on users- individual needs. Personalization and effective user profile management will be necessary to ensure the uptake and success of new services and devices and it is therefore important to focus on the users- requirements in this area and define solutions that meet these requirements. The work on personalization and user profiles emerged from earlier ETSI work on a Universal Communications Identifier (UCI) which is a unique identifier of the user rather than a range of identifiers of the many of communication devices or services (e.g. numbers of fixed phone at home/work, mobile phones, fax and email addresses). This paper describes work on personalization including standardized information and preferences and an architectural framework providing a description of how personalization can be integrated in Next Generation Networks, together with the UCI concept.

Keywords: Interoperability, Next Generation Network (NGN), Personalization, Universal Communications Identifier (UCI), User Profile Management (UPM)

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215 Mathematical Modeling of Gas Turbine Blade Cooling

Authors: А. Pashayev, C. Ardil, D. Askerov, R. Sadiqov, A. Samedov

Abstract:

In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and quasistationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine first stage nozzle blade.

Keywords: Mathematical Modeling, Gas Turbine Blade Cooling, Neural Networks, BIEM and FDM.

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214 Effect of Replacement of Unripe Banana Flour for Rice Flour on Physical Properties and Resistant Starch Content of Rice Noodle

Authors: W. Tiboonbun, M. Sungsri-in, A. Moongngarm

Abstract:

This work was conducted to improve the level of resistant starch (RS) in a rice noodle using unripe banana flour and to investigate the effect of substitution of unripe banana flour for rice flour on the physical properties of rice noodle. In order to prepare rice noodles, the unripe banana flour were replaced the rice flour with different degrees of substitutions including 0, 20, 40, 60, 80, and 100%. The results indicated that substitution of unripe banana flour was significantly affected the viscosity properties of noodle flour, color, cooking loss, RS and total starch content of noodle. It was found that the noodle prepared from 100% unripe banana indicated the greatest changes on the viscosity properties and color profiles. It also showed the highest values of cooking loss (2.53%), tensile strength (129.03%), and RS content (13.15%).

Keywords: Banana flour, Rice noodle, Resistant starch, Unripebanana flour

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213 Student Satisfaction Data for Work Based Learners

Authors: Rosie Borup, Hanifa Shah

Abstract:

This paper aims to describe how student satisfaction is measured for work-based learners as these are non-traditional learners, conducting academic learning in the workplace, typically their curricula have a high degree of negotiation, and whose motivations are directly related to their employers- needs, as well as their own career ambitions. We argue that while increasing WBL participation, and use of SSD are both accepted as being of strategic importance to the HE agenda, the use of WBL SSD is rarely examined, and lessons can be learned from the comparison of SSD from a range of WBL programmes, and increased visibility of this type of data will provide insight into ways to improve and develop this type of delivery. The key themes that emerged from the analysis of the interview data were: learners profiles and needs, employers drivers, academic staff drivers, organizational approach, tools for collecting data and visibility of findings. The paper concludes with observations on best practice in the collection, analysis and use of WBL SSD, thus offering recommendations for both academic managers and practitioners.

Keywords: Student satisfaction data, work based learning, employer engagement, NSS.

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212 Molding Properties of Cobalt-Chrome-Based Feedstocks Used in Low-Pressure Powder Injection Molding

Authors: Ehsan Gholami, Vincent Demers

Abstract:

Low-pressure powder injection molding is an emerging technology for cost-effectively producing complex shape metallic parts with the proper dimensional tolerances, either in high or in low production volumes. In this study, the molding properties of cobalt-chrome-based feedstocks were evaluated for use in a low-pressure powder injection molding process. The rheological properties of feedstock formulations were obtained by mixing metallic powder with a proprietary wax-based binder system. Rheological parameters such as reference viscosity, shear rate sensitivity index, and activation energy for viscous flow, were extracted from the viscosity profiles and introduced into the Weir model to calculate the moldability index. Feedstocks were experimentally injected into a spiral mold cavity to validate the injection performance calculated with the model.

Keywords: Binder, feedstock, moldability, powder injection molding, viscosity.

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211 Knowledge Mining in Web-based Learning Environments

Authors: Nittaya Kerdprasop, Kittisak Kerdprasop

Abstract:

The state of the art in instructional design for computer-assisted learning has been strongly influenced by advances in information technology, Internet and Web-based systems. The emphasis of educational systems has shifted from training to learning. The course delivered has also been changed from large inflexible content to sequential small chunks of learning objects. The concepts of learning objects together with the advanced technologies of Web and communications support the reusability, interoperability, and accessibility design criteria currently exploited by most learning systems. These concepts enable just-in-time learning. We propose to extend theses design criteria further to include the learnability concept that will help adapting content to the needs of learners. The learnability concept offers a better personalization leading to the creation and delivery of course content more appropriate to performance and interest of each learner. In this paper we present a new framework of learning environments containing knowledge discovery as a tool to automatically learn patterns of learning behavior from learners' profiles and history.

Keywords: Knowledge mining, Web-based learning, Learning environments.

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210 New Technologies for Modeling of Gas Turbine Cooled Blades

Authors: A. Pashayev, D. Askerov, R.Sadiqov, A. Samedov, C. Ardil

Abstract:

In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and cvazistationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine 1st stage nozzle blade

Keywords: multiconnected systems, method of the boundary integrated equations, splines, neural networks.

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209 Numerical Modeling of Gas Turbine Engines

Authors: A. Pashayev, D. Askerov, C. Ardil, R. Sadiqov

Abstract:

In contrast to existing methods which do not take into account multiconnectivity in a broad sense of this term, we develop mathematical models and highly effective combination (BIEM and FDM) numerical methods of calculation of stationary and quasi-stationary temperature field of a profile part of a blade with convective cooling (from the point of view of realization on PC). The theoretical substantiation of these methods is proved by appropriate theorems. For it, converging quadrature processes have been developed and the estimations of errors in the terms of A.Ziqmound continuity modules have been received. For visualization of profiles are used: the method of the least squares with automatic conjecture, device spline, smooth replenishment and neural nets. Boundary conditions of heat exchange are determined from the solution of the corresponding integral equations and empirical relationships. The reliability of designed methods is proved by calculation and experimental investigations heat and hydraulic characteristics of the gas turbine first stage nozzle blade.

Keywords: Multiconnected systems, method of the boundary integrated equations, splines, neural networks.

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208 Comparison of the Performance of GaInAsSb and GaSb Cells under Different Temperature Blackbody Radiations

Authors: Liangliang Tang, Chang Xu, Xingying Chen

Abstract:

GaInAsSb cells probably show better performance than GaSb cells in low-temperature thermophotovoltaic systems due to lower bandgap; however, few experiments proved this phenomenon so far. In this paper, numerical simulation is used to evaluate GaInAsSb and GaSb cells with similar structures under different radiation temperatures. We found that GaInAsSb cells with n-type emitters show slightly higher output power densities compared with that of GaSb cells with n-type emitters below 1,550 K-blackbody radiation, and the power density of the later cells will suppress the formers above this temperature point. During the temperature range of 1,000~2,000 K, the efficiencies of GaSb cells are about twice of GaInAsSb cells if perfect filters are used to prevent the emission of the non-absorbed long wavelength photons. Several parameters that affect the GaInAsSb cell were analyzed, such as doping profiles, thicknesses of GaInAsSb epitaxial layer and surface recombination velocity. The non-p junctions, i.e., n-type emitters are better for GaInAsSb cell fabrication, which is similar to that of GaSb cells.

Keywords: Thermophotovoltaic cell, GaSb, GaInAsSb, diffused emitters.

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207 Simultaneous Clustering and Feature Selection Method for Gene Expression Data

Authors: T. Chandrasekhar, K. Thangavel, E. N. Sathishkumar

Abstract:

Microarrays are made it possible to simultaneously monitor the expression profiles of thousands of genes under various experimental conditions. It is used to identify the co-expressed genes in specific cells or tissues that are actively used to make proteins. This method is used to analysis the gene expression, an important task in bioinformatics research. Cluster analysis of gene expression data has proved to be a useful tool for identifying co-expressed genes, biologically relevant groupings of genes and samples. In this work K-Means algorithms has been applied for clustering of Gene Expression Data. Further, rough set based Quick reduct algorithm has been applied for each cluster in order to select the most similar genes having high correlation. Then the ACV measure is used to evaluate the refined clusters and classification is used to evaluate the proposed method. They could identify compact clusters with feature selection method used to genes are selected.

Keywords: Clustering, Feature selection, Gene expression data, Quick reduct.

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206 Image Processing on Geosynthetic Reinforced Layers to Evaluate Shear Strength and Variations of the Strain Profiles

Authors: S. K. Khosrowshahi, E. Güler

Abstract:

This study investigates the reinforcement function of geosynthetics on the shear strength and strain profile of sand. Conducting a series of simple shear tests, the shearing behavior of the samples under static and cyclic loads was evaluated. Three different types of geosynthetics including geotextile and geonets were used as the reinforcement materials. An image processing analysis based on the optical flow method was performed to measure the lateral displacements and estimate the shear strains. It is shown that besides improving the shear strength, the geosynthetic reinforcement leads a remarkable reduction on the shear strains. The improved layer reduces the required thickness of the soil layer to resist against shear stresses. Consequently, the geosynthetic reinforcement can be considered as a proper approach for the sustainable designs, especially in the projects with huge amount of geotechnical applications like subgrade of the pavements, roadways, and railways.

Keywords: Image processing, soil reinforcement, geosynthetics, simple shear test, shear strain profile.

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205 Flow and Heat Transfer Mechanism Analysis in Outward Convex Asymmetrical Corrugated Tubes

Authors: Huaizhi Han, Bingxi Li, Yurong He, Rushan Bie, Zhao Wu

Abstract:

The flow and heat transfer mechanism in convex corrugated tubes have been investigated through numerical simulations in this paper. Two kinds of tube types named as symmetric corrugated tube (SCT) and asymmetric corrugated tube (ACT) are modeled and studied numerically based on the RST model. The predictive capability of RST model is examined in the corrugation wall in order to check the reliability of RST model under the corrugation wall condition. We propose a comparison between the RST modelling the corrugation wall with existing direct numerical simulation of Maaß C and Schumann U [14]. The numerical results pressure coefficient at different profiles between RST and DNS are well matched. The influences of large corrugation tough radii to heat transfer and flow characteristic had been considered. Flow and heat transfer comparison between SCT and ACT had been discussed. The numerical results show that ACT exhibits higher overall heat transfer performance than SCT.

Keywords: Asymmetric corrugated tube, RST, DNS, flow and heat transfer mechanism.

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204 A Numerical Study of the Interaction between Residual Stress Profiles Induced by Quasi-Static Plastification

Authors: G. F. Guimarães, A. R. de Faria, R. R. Rego, A. L. R. D’Oliveira

Abstract:

One of the most relevant phenomena in manufacturing is the residual stress state development through the manufacturing chain. In most cases, the residual stresses have their origin in the heterogenous plastification produced by the processes. Although a few manufacturing processes have been successfully approached by numerical modeling, there is still lack of understanding on how these processes' interactions will affect the final stress state. The objective of this work is to analyze the effect of the grinding procedure on the residual stress state generated by a quasi-static indentation. The model consists in a simplified approach of shot peening, modeling four cases with variations in indenter size and force. This model was validated through topography, measured by optical 3D focus-variation. The indentation model configured with two loads was then exposed to two grinding procedures and the result was analyzed. It was observed that the grinding procedure will have a significant effect on the stress state.

Keywords: plasticity, residual stress, finite element method, manufacturing

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203 Nanomechanical Characterization of Titanium Alloy Modified by Nitrogen Ion Implantation

Authors: Josef Sepitka, Petr Vlcak, Tomas Horazdovsky, Vratislav Perina

Abstract:

An ion implantation technique was used for designing the surface area of a titanium alloy and for irradiation-enhanced hardening of the surface. The Ti6Al4V alloy was treated by nitrogen ion implantation at fluences of 2·1017 and 4·1017 cm-2 and at ion energy 90 keV. The depth distribution of the nitrogen was investigated by Rutherford Backscattering Spectroscopy. The gradient of mechanical properties was investigated by nanoindentation. The continuous measurement mode was used to obtain depth profiles of the indentation hardness and the reduced storage modulus of the modified surface area. The reduced storage modulus and the hardness increase with increasing fluence. Increased fluence shifts the peak of the mechanical properties as well as the peak of nitrogen concentration towards to the surface. This effect suggests a direct relationship between mechanical properties and nitrogen distribution.

Keywords: Nitrogen ion implantation, titanium-based nanolayer, storage modulus, hardness, microstructure.

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202 Context for Simplicity: A Basis for Context-aware Systems Based on the 3GPP Generic User Profile

Authors: Enrico Rukzio, George N. Prezerakos, Giovanni Cortese, Eleftherios Koutsoloukas, Sofia Kapellaki

Abstract:

The paper focuses on the area of context modeling with respect to the specification of context-aware systems supporting ubiquitous applications. The proposed approach, followed within the SIMPLICITY IST project, uses a high-level system ontology to derive context models for system components which consequently are mapped to the system's physical entities. For the definition of user and device-related context models in particular, the paper suggests a standard-based process consisting of an analysis phase using the Common Information Model (CIM) methodology followed by an implementation phase that defines 3GPP based components. The benefits of this approach are further depicted by preliminary examples of XML grammars defining profiles and components, component instances, coupled with descriptions of respective ubiquitous applications.

Keywords: 3GPP, context, context-awareness, context model, information model, user model, XML

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201 Numerical Simulation of the Kurtosis Effect on the EHL Problem

Authors: S. Gao, S. Srirattayawong

Abstract:

In this study, a computational fluid dynamics (CFD) model has been developed for studying the effect of surface roughness profile on the EHL problem. The cylinders contact geometry, meshing and calculation of the conservation of mass and momentum equations are carried out using the commercial software packages ICEMCFD and ANSYS Fluent. The user defined functions (UDFs) for density, viscosity and elastic deformation of the cylinders as the functions of pressure and temperature are defined for the CFD model. Three different surface roughness profiles are created and incorporated into the CFD model. It is found that the developed CFD model can predict the characteristics of fluid flow and heat transfer in the EHL problem, including the main parameters such as pressure distribution, minimal film thickness, viscosity, and density changes. The results obtained show that the pressure profile at the center of the contact area directly relates to the roughness amplitude. A rough surface with kurtosis value of more than 3 has greater influence over the fluctuated shape of pressure distribution than in other cases.

Keywords: CFD, EHL, Kurtosis, Surface roughness.

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200 Reliability Assessment of Bangladesh Power System Using Recursive Algorithm

Authors: Nahid-Al-Masood, Jubaer Ahmed, Amina Hasan Abedin, S. R. Deeba, Faeza Hafiz, Mahmuda Begum

Abstract:

An electric utility-s main concern is to plan, design, operate and maintain its power supply to provide an acceptable level of reliability to its users. This clearly requires that standards of reliability be specified and used in all three sectors of the power system, i.e., generation, transmission and distribution. That is why reliability of a power system is always a major concern to power system planners. This paper presents the reliability analysis of Bangladesh Power System (BPS). Reliability index, loss of load probability (LOLP) of BPS is evaluated using recursive algorithm and considering no de-rated states of generators. BPS has sixty one generators and a total installed capacity of 5275 MW. The maximum demand of BPS is about 5000 MW. The relevant data of the generators and hourly load profiles are collected from the National Load Dispatch Center (NLDC) of Bangladesh and reliability index 'LOLP' is assessed for the period of last ten years.

Keywords: Recursive algorithm, LOLP, forced outage rate, cumulative probability.

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199 One-Dimensional Numerical Investigation of a Cylindrical Micro-Combustor Applying Electrohydrodynamics Effect

Authors: Behrouzinia P., Irani R. A., Saidi M.H.

Abstract:

In this paper, a one-dimensional numerical approach is used to study the effect of applying electrohydrodynamics on the temperature and species mass fraction profiles along the microcombustor. Premixed mixture is H2-Air with a multi-step chemistry (9 species and 19 reactions). In the micro-scale combustion because of the increasing ratio of area-to-volume, thermal and radical quenching mechanisms are important. Also, there is a significant heat loss from the combustor walls. By inserting a number of electrodes into micro-combustor and applying high voltage to them corona discharge occurs. This leads in moving of induced ions toward natural molecules and colliding with them. So this phenomenon causes the movement of the molecules and reattaches the flow to the walls. It increases the velocity near the walls that reduces the wall boundary layer. Consequently, applying electrohydrodynamics mechanism can enhance the temperature profile in the microcombustor. Ultimately, it prevents the flame quenching in microcombustor.

Keywords: micro-combustor, electrohydrodynamics, temperature profile, wall quenching

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198 Kerma Profile Measurements in CT Chest Scans– a Comparison of Methodologies

Authors: Bruno B. Oliveira, Arnaldo P. Mourão, Teógenes A. da Silva

Abstract:

The Brazilian legislation has only established diagnostic reference levels (DRLs) in terms of Multiple Scan Average Dose (MSAD) as a quality control parameter for computed tomography (CT) scanners. Compliance with DRLs can be verified by measuring the Computed Tomography Kerma Index (Ca,100) with a pencil ionization chamber or by obtaining the kerma distribution in CT scans with radiochromic films or rod shape lithium fluoride termoluminescent dosimeters (TLD-100). TL dosimeters were used to record kerma profiles and to determine MSAD values of a Bright Speed model GE CT scanner. Measurements were done with radiochromic films and TL dosimeters distributed in cylinders positioned in the center and in four peripheral bores of a standard polymethylmethacrylate (PMMA) body CT dosimetry phantom. Irradiations were done using a protocol for adult chest. The maximum values were found at the midpoint of the longitudinal axis. The MSAD values obtained with three dosimetric techniques were compared.

Keywords: Kerma profile, CT, MSAD, patient dosimetry

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197 Formulation and Evaluation of Niosomes Containing an Antihypertensive Drug

Authors: Sunil Kamboj, Suman Bala, Vipin Saini

Abstract:

Niosomes were formulated with an aim of enhancing the oral bioavailability of losartan potassium and formulated in different molar ratios of surfactant, cholesterol and dicetyl phosphate. The formulated niosomes were found in range of 54.98 µm to 107.85 µm in size. Formulations with 1:1 ratio of surfactant and cholesterol have shown maximum entrapment efficiencies. Niosomes with sorbitan monostearate showed maximum drug release and zero order release kinetics, at the end of 24 hours. The in vivo study has shown the significant enhancement in oral bioavailability of losartan potassium in rats, after a dose of 10 mg/kg. The average relative bioavailability in relation with pure drug solution was found 2.56, indicates more than two fold increase in oral bioavailability. A significant increment in MRT reflects the release retarding ability of the vesicles. In conclusion, niosomes could be a promising delivery of losartan potassium with improved oral bioavailability and prolonged release profiles.

Keywords: Non-ionic surfactant vesicles, losartan potassium, oral bioavailability, controlled release.

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196 Potential cIBR-Conjugated PLGA Nanoparticles for Selective Targeting to Leukemic Cells

Authors: Rungsinee Phongpradist, Sawitree Chiampanichayakul, Singkome Tima, Teruna J. Siahaan, Cory J. Berkland, Songyot Anuchapreeda, Chadarat Ampasavate

Abstract:

The expression of LFA-1 diverges from the physiological condition, thus active targeting carrier can provide the benefits from difference into LFA-1 expression in various conditions. Here, the selectivity of cIBR-conjugated nanoparticles (cIBR-NPs), in terms of uptake, was investigated using PBMCs, Mixed PBMCMolt- 3 cells and Molt-3 cells. The expressions of LFA-1 on Molt-3 cells, from flow cytometry and Western blot, possessed the highest level whereas PBMCs showed the lowest level. The kinetic uptake profiles of cIBR-NPs were obtained by flow cytometry, which the degree of cellular uptake presented a similar trend with the level of LFA-1 indicating the influence of LFA-1 expression on the cellular uptake of cIBR-NPs. The conformation of LFA-1 had a slight effect on the cellular uptake of cIBR-NPs. Overall we demonstrated that cIBR-NPs enhanced cellular uptake and improved the selectivity of drug carriers to LFA-1 on the leukemia cells, which related with the order of LFA-1 expression.

Keywords: cIBR, LFA-1, Molt-3, PBMCs

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195 Intelligent Path Tracking Hybrid Fuzzy Controller for a Unicycle-Type Differential Drive Robot

Authors: Abdullah M. Almeshal, Mohammad R. Alenezi, Muhammad Moaz

Abstract:

In this paper, we discuss the performance of applying hybrid spiral dynamic bacterial chemotaxis (HSDBC) optimisation algorithm on an intelligent controller for a differential drive robot. A unicycle class of differential drive robot is utilised to serve as a basis application to evaluate the performance of the HSDBC algorithm. A hybrid fuzzy logic controller is developed and implemented for the unicycle robot to follow a predefined trajectory. Trajectories of various frictional profiles and levels were simulated to evaluate the performance of the robot at different operating conditions. Controller gains and scaling factors were optimised using HSDBC and the performance is evaluated in comparison to previously adopted optimisation algorithms. The HSDBC has proven its feasibility in achieving a faster convergence toward the optimal gains and resulted in a superior performance.

Keywords: Differential drive robot, hybrid fuzzy controller, optimization, path tracking, unicycle robot.

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194 Effects of Photovoltaic System Introduction in Detached Houses with All-Electrified Residential Equipment in Japan

Authors: Qingrong Liu, Tetsuo Hayashi, Yuji Ryu

Abstract:

In this paper, in order to investigate the effects of photovoltaic system introduction to detached houses in Japan, two kinds of works were done. Firstly, the hourly generation amount of a 4.2kW photovoltaic system were simulated in 46 cities to investigate the potential of the system in different regions in Japan using a simulation model of photovoltaic system. Secondly, based on the simulated electricity generation amount, the energy saving, the environmental and the economic effect of the photovoltaic system were examined from hourly to annual timescales, based upon calculations of typical electricity, heating, cooling and hot water supply load profiles for Japanese dwellings. The above analysis was carried out using a standard year-s hourly weather data for the different city provided by the Expanded AMeDAS Weather Data issued by AIJ (Architectural Institute of Japan).

Keywords: Photovoltaic system, Energy saving, Environmental effect, Japanese dwelling, Detached house.

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193 Kinetic Parameter Estimation from Thermogravimetry and Microscale Combustion Calorimetry

Authors: Rhoda Afriyie Mensah, Lin Jiang, Solomon Asante-Okyere, Xu Qiang, Cong Jin

Abstract:

Flammability analysis of extruded polystyrene (XPS) has become crucial due to its utilization as insulation material for energy efficient buildings. Using the Kissinger-Akahira-Sunose and Flynn-Wall-Ozawa methods, the degradation kinetics of two pure XPS from the local market, red and grey ones, were obtained from the results of thermogravity analysis (TG) and microscale combustion calorimetry (MCC) experiments performed under the same heating rates. From the experiments, it was discovered that red XPS released more heat than grey XPS and both materials showed two mass loss stages. Consequently, the kinetic parameters for red XPS were higher than grey XPS. A comparative evaluation of activation energies from MCC and TG showed an insignificant degree of deviation signifying an equivalent apparent activation energy from both methods. However, different activation energy profiles as a result of the different chemical pathways were presented when the dependencies of the activation energies on extent of conversion for TG and MCC were compared.

Keywords: Flammability, microscale combustion calorimetry, thermogravity analysis, thermal degradation, kinetic analysis.

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192 Interaction of Building Stones with Inorganic Water-Soluble Salts

Authors: Z. Pavlík, J. Žumár, M. Pavlíková, R. Černý

Abstract:

Interaction of inorganic water-soluble salts and building stones is studied in the paper. Two types of sandstone and one type of spongillite as representatives of materials used in historical masonry are subjected to experimental testing. Within the performed experiments, measurement of moisture and chloride concentration profiles is done in order to get input data for computational inverse analysis. Using the inverse analysis, moisture diffusivity and chloride diffusion coefficient of investigated materials are accessed. Additionally, the effect of salt presence on water vapor storage is investigated using dynamic vapor sorption device. The obtained data represents valuable information for restoration of historical masonry and give evidence on the performance of studied stones in contact with water soluble salts.

Keywords: Moisture and chloride transport, sandstone, spongillite, moisture diffusivity, chloride diffusion coefficient.

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191 Spherical Harmonic Based Monostatic Anisotropic Point Scatterer Model for RADAR Applications

Authors: Eric Huang, Coleman DeLude, Justin Romberg, Saibal Mukhopadhyay, Madhavan Swaminathan

Abstract:

High-performance computing (HPC) based emulators can be used to model the scattering from multiple stationary and moving targets for RADAR applications. These emulators rely on the RADAR Cross Section (RCS) of the targets being available in complex scenarios. Representing the RCS using tables generated from EM simulations is oftentimes cumbersome leading to large storage requirements. In this paper, we proposed a spherical harmonic based anisotropic scatterer model to represent the RCS of complex targets. The problem of finding the locations and reflection profiles of all scatterers can be formulated as a linear least square problem with a special sparsity constraint. We solve this problem using a modified Orthogonal Matching Pursuit algorithm. The results show that the spherical harmonic based scatterer model can effectively represent the RCS data of complex targets.

Keywords: RADAR, RCS, high performance computing, point scatterer model

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