Search results for: Age Difference at Marriage
595 Convective Heat Transfer of Viscoelastic Flow in a Curved Duct
Authors: M. Norouzi, M. H. Kayhani, M. R. H. Nobari, M. Karimi Demneh
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In this paper, fully developed flow and heat transfer of viscoelastic materials in curved ducts with square cross section under constant heat flux have been investigated. Here, staggered mesh is used as computational grids and flow and heat transfer parameters have been allocated in this mesh with marker and cell method. Numerical solution of governing equations has being performed with FTCS finite difference method. Furthermore, Criminale-Eriksen- Filbey (CEF) constitutive equation has being used as viscoelastic model. CEF constitutive equation is a suitable model for studying steady shear flow of viscoelastic materials which is able to model both effects of the first and second normal stress differences. Here, it is shown that the first and second normal stresses differences have noticeable and inverse effect on secondary flows intensity and mean Nusselt number which is the main novelty of current research.Keywords: Viscoelastic, fluid flow, heat convection, CEF model, curved duct, square cross section.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2155594 Study on Connecting Method of Box Pontoons
Authors: Young-Jun You, Youn-Ju Jeong, Min-Su Park, Du-Ho Lee
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Due to a lot of limited conditions, a large box type floating structure is inevitably constructed by connecting many pontoons. When a floating structure is made with concrete, concrete shear key with saw-teeth shape is often used to carry shear force. Match casting for the shear key and precise construction on a sea are very important for making separated two pontoons as one body but those are not easy work and may increase construction time and cost. To solve this problem, one-way shear key is studied in this paper for a connected part where there is some difference between upward and downward shear force. It has only one inclined plane and can resist shear force in one direction. Big shear force is resisted by concrete which forms an inclined plane and small shear force is resisted by steel bar. This system can reduce manufacturing cost of individual pontoon and construction time and cost for constructing a floating structure on a sea. In this paper, the feasibility study about one-way shear key system is performed by comparing with design example.
Keywords: Connection, floating container terminal, pontoon, pre-stressing, shear key.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3112593 Comparative Evaluation of Color-Based Video Signatures in the Presence of Various Distortion Types
Authors: Aritz Sánchez de la Fuente, Patrick Ndjiki-Nya, Karsten Sühring, Tobias Hinz, Karsten Müller, Thomas Wiegand
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The robustness of color-based signatures in the presence of a selection of representative distortions is investigated. Considered are five signatures that have been developed and evaluated within a new modular framework. Two signatures presented in this work are directly derived from histograms gathered from video frames. The other three signatures are based on temporal information by computing difference histograms between adjacent frames. In order to obtain objective and reproducible results, the evaluations are conducted based on several randomly assembled test sets. These test sets are extracted from a video repository that contains a wide range of broadcast content including documentaries, sports, news, movies, etc. Overall, the experimental results show the adequacy of color-histogram-based signatures for video fingerprinting applications and indicate which type of signature should be preferred in the presence of certain distortions.
Keywords: color histograms, robust hashing, video retrieval, video signature
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1447592 An Attack on the Lucas Based El-Gamal Cryptosystem in the Elliptic Curve Group Over Finite Field Using Greater Common Divisor
Authors: Lee Feng Koo, Tze Jin Wong, Pang Hung Yiu, Nik Mohd Asri Nik Long
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Greater common divisor (GCD) attack is an attack that relies on the polynomial structure of the cryptosystem. This attack required two plaintexts differ from a fixed number and encrypted under same modulus. This paper reports a security reaction of Lucas Based El-Gamal Cryptosystem in the Elliptic Curve group over finite field under GCD attack. Lucas Based El-Gamal Cryptosystem in the Elliptic Curve group over finite field was exposed mathematically to the GCD attack using GCD and Dickson polynomial. The result shows that the cryptanalyst is able to get the plaintext without decryption by using GCD attack. Thus, the study concluded that it is highly perilous when two plaintexts have a slight difference from a fixed number in the same Elliptic curve group over finite field.
Keywords: Decryption, encryption, elliptic curve, greater common divisor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 705591 Ready or Not? Markers of Starting Romantic Intimacy at Emerging Adulthood: The Turkish Experience
Authors: Ali Eryılmaz, Hasan Atak
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Emerging adulthood, the new period which is especially prevalent in the developed or industrialized countries during ages 18 to 29, is a new conceptualization proposed by Arnett. Intimacy is a superordinate concept which includes intimate interaction and intimate relationship. This study includes two proceses which are scale development and conduction of gender differences about markers of starting romantic intimacy among Turkish emerging adults. In first process, Markers of Starting Romantic Intimacy Scale, with 17 items and 5 factors, was developed using by 220 participants. In the second step, the scale was administered to 318 Turkish male and female emerging adults between ages 22 and 25. Results show that there is no significant difference between gender and total score of the scale. With respect to gender, there are significant differences between gender and in four subscales which are self perception, affective and cognitive intimacy, self knowledge and romantic verbalizations. Moreover, there is no significant relationship between gender and behavioral intimacy subscale.Keywords: Emerging Adulthood, Turkey, Romantic Intimac, Relationship, Marker.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1997590 Creating Maintenance Cost Model for University Buildings
Authors: AbdulLateef A. Olanrewaju, Arazi Idrus, Mohd F. Khamidi
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Maintenance costs incurred on building differs. The difference can be as results of the types, functions, age, building health index, size, form height, location and complexity of the building. These are contributing to the difficulty in maintenance development of deterministic maintenance cost model. This paper is concerns with reporting the preliminary findings on the creation of building maintenance cost distributions for universities in Malaysia. This study is triggered by the need to provide guides on maintenance costs distributions for decision making. For this purpose, a survey questionnaire was conducted to investigate the distribution of maintenance costs in the universities. Altogether, responses were received from twenty universities comprising both private and publicly owned. The research found that engineering services, roofing and finishes were the elements contributing the larger segment of the maintenance costs. Furthermore, the study indicates the significance of maintenance cost distribution as decision making tool towards maintenance management.Keywords: Performance matrix, university buildings, costmodel, Malaysia
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2037589 A Semi-Implicit Phase Field Model for Droplet Evolution
Authors: M. H. Kazemi, D. Salac
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A semi-implicit phase field method for droplet evolution is proposed. Using the phase field Cahn-Hilliard equation, we are able to track the interface in multiphase flow. The idea of a semi-implicit finite difference scheme is reviewed and employed to solve two nonlinear equations, including the Navier-Stokes and the Cahn-Hilliard equations. The use of a semi-implicit method allows us to have larger time steps compared to explicit schemes. The governing equations are coupled and then solved by a GMRES solver (generalized minimal residual method) using modified Gram-Schmidt orthogonalization. To show the validity of the method, we apply the method to the simulation of a rising droplet, a leaky dielectric drop and the coalescence of drops. The numerical solutions to the phase field model match well with existing solutions over a defined range of variables.
Keywords: Coalescence, leaky dielectric, numerical method, phase field, rising droplet, semi-implicit method.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 878588 The Temperature Effects on the Microstructure and Profile in Laser Cladding
Authors: P. C. Chiu, Jehnming Lin
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In this study, a 50-W CO2 laser was used for the clad of 304L powders on the stainless steel substrate with a temperature sensor and image monitoring system. The laser power and cladding speed and focal position were modified to achieve the requirement of the workpiece flatness and mechanical properties. The numerical calculation is based on ANSYS to analyze the temperature change of the moving heat source at different surface positions when coating the workpiece, and the effect of the process parameters on the bath size was discussed. The temperature of stainless steel powder in the nozzle outlet reacting with the laser was simulated as a process parameter. In the experiment, the difference of the thermal conductivity in three-dimensional space is compared with single-layer cladding and multi-layer cladding. The heat dissipation pattern of the single-layer cladding is the steel plate and the multi-layer coating is the workpiece itself. The relationship between the multi-clad temperature and the profile was analyzed by the temperature signal from an IR pyrometer.Keywords: Laser cladding, temperature, profile, microstructure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1067587 Water Reallocation Policies – The Importance of Rural and Urban Differences in Alberta, Canada
Authors: Henning Bjornlund, Alec Zuo, Sarah Wheeler, Rob de Loë
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There is currently intensive debate in Alberta, Canada, regarding rural to urban water reallocation. This paper explores the demographic and attitudinal influences that are associated with the acceptance of water reallocation policies and whether such acceptance differs between urban and rural residents. We investigate three policy orientations in regards to water policies: i) government intervention; ii) environmental protection; and iii) protecting irrigators- water rights. We find that urban dwellers are more likely to favour government intervention while rural dwellers are more likely to support policies that aim at protecting irrigators- water rights. While urban dwellers are also more likely to favour environmental protection, the difference is not statistically significant. We also find that other factors have a significant impact on policy choice irrespective of residence such as demographic and socioeconomic factors as well as the values people hold toward water and the environment.Keywords: Canada, rural, urban, water transfers.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1397586 Eosinophils and Platelets: Players of the Game in Morbid Obese Boys with Metabolic Syndrome
Authors: Orkide Donma, Mustafa M. Donma
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Childhood obesity, which may lead to increased risk for heart diseases in children as well as adults, is one of the most important health problems throughout the world. Prevalences of morbid obesity and metabolic syndrome (MetS) are being increased during childhood age group. MetS is a cluster of metabolic and vascular abnormalities including hypercoagulability and an increased risk of cardiovascular diseases (CVDs). There are also some relations between some components of MetS and leukocytes. The aim of this study is to investigate complete blood cell count parameters that differ between morbidly obese boys and girls with MetS diagnosis. A total of 117 morbid obese children with MetS consulted to Department of Pediatrics in Faculty of Medicine Hospital at Namik Kemal University were included into the scope of the study. The study population was classified based upon their genders (60 girls and 57 boys). Their heights and weights were measured and body mass index (BMI) values were calculated. WHO BMI-for age and sex percentiles were used. The values above 99 percentile were defined as morbid obesity. Anthropometric measurements were performed. Waist-to-hip and head-to-neck ratios as well as homeostatic model assessment of insulin resistance (HOMA-IR) were calculated. Components of MetS (central obesity, glucose intolerance, high blood pressure, high triacylglycerol levels, low levels of high density lipoprotein cholesterol) were determined. Hematological variables were measured. Statistical analyses were performed using SPSS. The degree for statistical significance was p ≤ 0.05. There was no statistically significant difference between the ages (11.2±2.6 years vs 11.2±3.0 years) and BMIs (28.6±5.2 kg/m2 vs 29.3±5.2 kg/m2) of boys and girls (p ≥ 0.05), respectively. Significantly increased waist-to-hip ratios were obtained for boys (0.94±0.08 vs 0.91±0.06; p=0.023). Significantly elevated values of hemoglobin (13.55±0.98 vs 13.06±0.82; p=0.004), mean corpuscular hemoglobin concentration (33.79±0.91 vs 33.21±1.14; p=0.003), eosinophils (0.300±0.253 vs 0.196±0.197; p=0.014), and platelet (347.1±81.7 vs 319.0±65.9; p=0.042) were detected for boys. There was no statistically significant difference between the groups in terms of neutrophil/lymphocyte ratios as well as HOMA-IR values (p ≥ 0.05). Statistically significant gender-based differences were found for hemoglobin as well as mean corpuscular hemoglobin concentration and hence, separate reference intervals for two genders should be considered for these parameters. Eosinophils may contribute to the development of thrombus in acute coronary syndrome. Eosinophils are also known to make an important contribution to mechanisms related to thrombosis pathogenesis in acute myocardial infarction. Increased platelet activity is observed in patients with MetS and these individuals are more susceptible to CVDs. In our study, elevated platelets described as dominant contributors to hypercoagulability and elevated eosinophil counts suggested to be related to the development of CVDs observed in boys may be the early indicators of the future cardiometabolic complications in this gender.Keywords: Children, complete blood count, gender, metabolic syndrome.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1071585 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
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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
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1938584 MCDM Spectrum Handover Models for Cognitive Wireless Networks
Authors: Cesar Hernández, Diego Giral, Fernando Santa
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Spectrum handover is a significant topic in the cognitive radio networks to assure an efficient data transmission in the cognitive radio user’s communications. This paper proposes a comparison between three spectrum handover models: VIKOR, SAW and MEW. Four evaluation metrics are used. These metrics are, accumulative average of failed handover, accumulative average of handover performed, accumulative average of transmission bandwidth and, accumulative average of the transmission delay. As a difference with related work, the performance of the three spectrum handover models was validated with captured data of spectrum occupancy in experiments performed at the GSM frequency band (824 MHz - 849 MHz). These data represent the actual behavior of the licensed users for this wireless frequency band. The results of the comparison show that VIKOR Algorithm provides a 15.8% performance improvement compared to SAW Algorithm and, it is 12.1% better than the MEW Algorithm.Keywords: Cognitive radio, decision making, MEW, SAW, spectrum handover, VIKOR.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2155583 Comparative Study of Transformed and Concealed Data in Experimental Designs and Analyses
Authors: K. Chinda, P. Luangpaiboon
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This paper presents the comparative study of coded data methods for finding the benefit of concealing the natural data which is the mercantile secret. Influential parameters of the number of replicates (rep), treatment effects (τ) and standard deviation (σ) against the efficiency of each transformation method are investigated. The experimental data are generated via computer simulations under the specified condition of the process with the completely randomized design (CRD). Three ways of data transformation consist of Box-Cox, arcsine and logit methods. The difference values of F statistic between coded data and natural data (Fc-Fn) and hypothesis testing results were determined. The experimental results indicate that the Box-Cox results are significantly different from natural data in cases of smaller levels of replicates and seem to be improper when the parameter of minus lambda has been assigned. On the other hand, arcsine and logit transformations are more robust and obviously, provide more precise numerical results. In addition, the alternate ways to select the lambda in the power transformation are also offered to achieve much more appropriate outcomes.Keywords: Experimental Designs, Box-Cox, Arcsine, Logit Transformations.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1622582 Kinetic Spectrophotometric Determination of Ramipril in Commercial Dosage Forms
Authors: Nafisur Rahman, Habibur Rahman, Syed Najmul Hejaz Azmi
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This paper presents a simple and sensitive kinetic spectrophotometric method for the determination of ramipril in commercial dosage forms. The method is based on the reaction of the drug with 1-chloro-2,4-dinitrobenzene (CDNB) in dimethylsulfoxide (DMSO) at 100 ± 1ºC. The reaction is followed spectrophotometrically by measuring the rate of change of the absorbance at 420 nm. Fixed-time (ΔA) and equilibrium methods are adopted for constructing the calibration curves. Both the calibration curves were found to be linear over the concentration ranges 20 - 220 μg/ml. The regression analysis of calibration data yielded the linear equations: Δ A = 6.30 × 10-4 + 1.54 × 10-3 C and A = 3.62 × 10-4 + 6.35 × 10-3 C for fixed time (Δ A) and equilibrium methods, respectively. The limits of detection (LOD) for fixed time and equilibrium methods are 1.47 and 1.05 μg/ml, respectively. The method has been successfully applied to the determination of ramipril in commercial dosage forms. Statistical comparison of the results shows that there is no significant difference between the proposed methods and Abdellatef-s spectrophotometric method.Keywords: Equilibrium method, Fixed-time (ΔA) method, Ramipril, Spectrophotometry.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2301581 Porous Effect on Heat Transfer of Non Uniform Velocity Inlet Flow Using LBM
Authors: A. Hasanpour, M. Farhadi, K.Sedighi, H.R.Ashorynejad
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A numerical study of flow in a horizontally channel partially filled with a porous screen with non-uniform inlet has been performed by lattice Boltzmann method (LBM). The flow in porous layer has been simulated by the Brinkman-Forchheimer model. Numerical solutions have been obtained for variable porosity models and the effects of Darcy number and porosity have been studied in detail. It is found that the flow stabilization is reliant on the Darcy number. Also the results show that the stabilization of flow field and heat transfer is depended to Darcy number. Distribution of stream field becomes more stable by decreasing Darcy number. Results illustrate that the effect of variable porosity is significant just in the region of the solid boundary. In addition, difference between constant and variable porosity models is decreased by decreasing the Darcy number.Keywords: Lattice Boltzmann Method, Porous Media, Variable Porosity, Flow Stabilization
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1929580 A Study of Structural Damage Detection for Spacecraft In-Orbit Based on Acoustic Sensor Array
Authors: Lei Qi, Rongxin Yan, Lichen Sun
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With the increasing of human space activities, the number of space debris has increased dramatically, and the possibility that spacecrafts on orbit are impacted by space debris is growing. A method is of the vital significance to real-time detect and assess spacecraft damage, determine of gas leak accurately, guarantee the life safety of the astronaut effectively. In this paper, acoustic sensor array is used to detect the acoustic signal which emits from the damage of the spacecraft on orbit. Then, we apply the time difference of arrival and beam forming algorithm to locate the damage and leakage. Finally, the extent of the spacecraft damage is evaluated according to the nonlinear ultrasonic method. The result shows that this method can detect the debris impact and the structural damage, locate the damage position, and identify the damage degree effectively. This method can meet the needs of structural damage detection for the spacecraft in-orbit.
Keywords: Acoustic sensor array, spacecraft, damage assessment, leakage location.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1121579 Improving Water Productivity of Chickpea by the Use of Deficit Irrigation with Treated Domestic Wastewater
Authors: Hirich A., Choukr-allah R., Jacobsen S-E., Hamdy A., El youssfi L., El Omari H.
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An experiment was performed in the south of Morocco in order to evaluate the effect of deficit irrigation by treated wastewater on chickpea production. We applied six irrigation treatments on a local variety of chickpea by supplying alternatively 50 or 100% of ETm in a completely randomized design. We found a highly significant difference between treatments in terms of biomass production. Drought stress during the vegetative period showed highest yield with 6.5 t/ha which was more than the yield obtained for the control (4.9 t/ha). The optimal crop stage in which deficit irrigation can be applied is the vegetative growth stage, as the crop has a chance to develop its root system, to be able to cover the plant needs for water and nutrient supply during the rest of cycle, and non stress conditions during the flowering and seed filling stages allow the plant to optimize its photosynthesis and carbon translocation, therefore increase its productivity.Keywords: chickpea, crop stages, drought stress, water productivity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3521578 Experimental and Theoretical Investigation on Notched Specimens Life Under Bending Loading
Authors: Nasim Daemi, Gholam Hossein Majzoobi
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In this work, bending fatigue life of notched specimens with various notch geometries and dimensions is investigated by experiment and Manson-Caffin theoretical method. In this theoretical method, fatigue life of notched specimens is calculated using the fatigue life obtained from the experiments for plain specimens (without notch). Three notch geometries including ∪-shape, ∨-shape and C -shape notches are considered in this investigation. The experiments are conducted on a rotary bending Moore machine. The specimens are made of a low carbon steel alloy, which has wide application in industry. The stress- life curves are captured for all notched specimen by experiment. The results indicate that Manson-Caffin analytical method cannot adequately predict the fatigue life of notched specimen. However, it seems that the difference between the experiments and Manson-Caffin predictions can be compensated by a proportional factor.Keywords: fatigue life, Mason-Caffin method, notchedspecimen, stress-life curve.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1950577 Antimicrobial Properties of Copper in Gram-Negative and Gram-Positive Bacteria
Authors: Travis J. Meyer, Jasodra Ramlall, Phyo Thu, Nidhi Gadura
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For centuries humans have used the antimicrobial properties of copper to their advantage. Yet, after all these years the underlying mechanisms of copper mediated cell death in various microbes remain unclear. We had explored the hypothesis that copper mediated increased levels of lipid peroxidation in the membrane fatty acids is responsible for increased killing in Escherichia coli. In this study we show that in both gram positive (Staphylococcus aureus) and gram negative (Pseudomonas aeruginosa) bacteria there is a strong correlation between copper mediated cell death and increased levels of lipid peroxidation. Interestingly, the non-spore forming gram positive bacteria as well as gram negative bacteria show similar patterns of cell death, increased levels of lipid peroxidation, as well as genomic DNA degradation, however there is some difference in loss in membrane integrity upon exposure to copper alloy surface.
Keywords: Antimicrobial, copper, gram positive, gram negative.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5593576 Development of Organizational Justice in Incentive Allocation of the Thai Public Sector
Authors: Kalayanee Koonmee
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An incentive for performance, as one subsystem of a new performance management system, has been implemented in the Thai public sector since 2004. This research investigates the development of organizational justice in the incentive allocation by comparing the roles of distributive and procedural justice on national personnel-s attitudinal outcomes (incentive satisfaction and job performance) between 2 periods, i.e. 2006 and 2008. The data were collected via self-administered questionnaires completed by national government officers and employees. They were stratified using multistage sampling with 2,600 usable samples or 72.0% response rate in 2006, and 1,969 usable samples or 59.3% in 2008. The findings are: (1) There is no difference in means between the two periods relating to distributive justice, procedural justice, incentive satisfaction and job performance. (2) Distributive justice and procedural justice played more important roles in predicting incentive satisfaction and job performance in 2008 than in 2006.Keywords: Distributive justice, incentive allocation, proceduraljustice, Thai public sector.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1524575 Influence of Solution Chemistry on Adsorption of Perfluorooctanesulfonate (PFOS) and Perfluorooctanoate (PFOA) on Boehmite
Authors: Fei Wang, Kaimin Shih
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The persistent nature of perfluorochemicals (PFCs) has attracted global concern in recent years. Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are the most commonly found PFC compounds, and thus their fate and transport play key roles in PFC distribution in the natural environment. The kinetic behavior of PFOS or PFOA on boehmite consists of a fast adsorption process followed by a slow adsorption process which may be attributed to the slow transport of PFOS or PFOA into the boehmite pore surface. The adsorption isotherms estimated the maximum adsorption capacities of PFOS and PFOA on boehmite as 0.877 μg/m2 and 0.633 μg/m2, with the difference primarily due to their different functional groups. The increase of solution pH led to a moderate decrease of PFOS and PFOA adsorption, owing to the increase of ligand exchange reactions and the decrease of electrostatic interactions. The presence of NaCl in solution demonstrated negative effects for PFOS and PFOA adsorption on boehmite surfaces, with potential mechanisms being electrical double layer compression, competitive adsorption of chloride.
Keywords: PFOS, PFOA, adsorption, electrostatic interaction, ligand exchange
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2356574 Flight Control of TUAV with Coaxial Rotor and Ducted Fan Configuration by NARMA-L2 Controllers for Enhanced Situational Awareness
Authors: Igor Astrov, Andrus Pedai, Boris Gordon
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This paper focuses on a critical component of the situational awareness (SA), the control of autonomous vertical flight for tactical unmanned aerial vehicle (TUAV). With the SA strategy, we proposed a two stage flight control procedure using two autonomous control subsystems to address the dynamics variation and performance requirement difference in initial and final stages of flight trajectory for an unmanned helicopter model with coaxial rotor and ducted fan configuration. This control strategy for chosen model of TUAV has been verified by simulation of hovering maneuvers using software package Simulink and demonstrated good performance for fast stabilization of engines in hovering, consequently, fast SA with economy in energy can be asserted during search-and-rescue operations.
Keywords: Coaxial rotors, ducted fan, NARMA-L2 neurocontroller, situational awareness, tactical unmanned aerial vehicle.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2313573 Profit and Nonprofit Sports Clubs: Financial and Organizational Comparison in Poland
Authors: Wojciech B. Cieśliński, Igor Perechuda
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The paper identifies the features of Polish sports clubs in the particular organizational forms: profit and nonprofit. Identification and description of these features is carried out in terms of financial efficiency of the given organizational form. Under the terms of the efficiency the research allows you to specify the advantages of particular organizational sports club form and the following limitations. Paper considers features of sports clubs in range of Polish conditions as legal regulations. The sources of the functioning efficiency of sports clubs may lie in the organizational forms in which they operate. Each of the available forms can be considered either a for-profit or nonprofit enterprise. Depending on this classification there are different capabilities of increasing organizational and financial efficiency of a given sports club. Authors start with general classification and difference between for-profit and non-profit sport clubs. Next identifies specific financial and organizational conditions of both organizational form and then show examples of mixed activity forms and their efficiency effect.Keywords: Financial efficiency, for-profit, non-profit, sports club.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2039572 Tool Wear of (Ti,W,Si)N-Coated WC-Ni-Based Cemented Carbide in Cutting Hardened Steel
Authors: Tadahiro Wada, Shinichi Enoki, Hiroyuki Hanyu
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In this study, WC-Ni-based cemented carbides having different nickel contents were used as the substrate for cutting tool materials. Hardened steel was turned by a (Ti,W,Si)N-coated WC-Ni-based cemented carbide tool, and the tool wear was experimentally investigated. The following results were obtained: (1) In the (Ti,W,Si)N-coated WC-Ni-based cemented carbide, the hardness of the coating film was not much different from the content of the binding material, Ni, and the adhesion strength increased with a decrease in Ni content. (2) There is little difference between the wear progress of the (Ti,W,Si)N-coated WC-7%Ni-based cemented carbide tool and that of the (Ti,W,Si)N-coated WC-6%Co-based cemented carbide tool. (3) The wear progress of the (Ti,W,Si)N-coated WC-Ni-based cemented carbide became slower with a decrease in Ni content.
From the above, it is has become clear that WC-Ni-based cemented carbide can be used as a substrate for cutting tool materials.
Keywords: Rare metals, turning, WC-Ni-based cemented carbide, (Ti, W, Si)N coating film, hardened steel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2839571 1-D Modeling of Hydrate Decomposition in Porous Media
Authors: F. Esmaeilzadeh, M. E. Zeighami, J. Fathi
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This paper describes a one-dimensional numerical model for natural gas production from the dissociation of methane hydrate in hydrate-capped gas reservoir under depressurization and thermal stimulation. Some of the hydrate reservoirs discovered are overlying a free-gas layer, known as hydrate-capped gas reservoirs. These reservoirs are thought to be easiest and probably the first type of hydrate reservoirs to be produced. The mathematical equations that can be described this type of reservoir include mass balance, heat balance and kinetics of hydrate decomposition. These non-linear partial differential equations are solved using finite-difference fully implicit scheme. In the model, the effect of convection and conduction heat transfer, variation change of formation porosity, the effect of using different equations of state such as PR and ER and steam or hot water injection are considered. In addition distributions of pressure, temperature, saturation of gas, hydrate and water in the reservoir are evaluated. It is shown that the gas production rate is a sensitive function of well pressure.
Keywords: Hydrate reservoir, numerical modeling, depressurization, thermal stimulation, gas generation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2054570 The Role of the Ethnos of Intellect in Legal and Informatical Observation of “Information Society“
Authors: Guranda Tevdoradze
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By the end of XX century in the structure of humanity some changes have been provoked: a new ethnos - Ethnos of Intellect is formed and is still being formed, beside the historical types of ethnoses: open ethnos, closed ethnos, wandering ethnos, dead ethnos, - and this event was caused by the technical progress, development of informational and transport communications, especially - by creation of Internet. The Ethnos of Intellect is something very close to the ÔÇ×Information Society“ described by J. Ellule and Y. Masuda that was regarded as the culture of XXI century, being an antithesis for technical and technicistical civilizations, but it-s necessary to indicate also the essential difference between these concepts: the Ethnos of Intellect is the antithesis of Socium. The existence of such an ethnos within human society that has already become an Information Society itself is extremely important in observing legally and informatically a new kind of reins in the hands of the political power, revealing every attempt to violate the human rights of simple citizens. A concrete example of some conjunction points of legal informatics and informatical law in a certain kind of ambiental studies of the project ''State Registre of Population'' in Russia is very eloquent.
Keywords: Culturology, Legal Informatics, Sociology of Groups.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1552569 Optimization of Propulsion in Flapping Micro Air Vehicles Using Genetic Algorithm Method
Authors: Mahdi Abolfazli, Ebrahim Barati, Hamid Reza Karbasian
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In this paper the kinematic parameters of a regular Flapping Micro Air Vehicle (FMAV) is investigated. The optimization is done using multi-objective Genetic algorithm method. It is shown that the maximum propulsive efficiency is occurred on the Strouhal number of 0.2-0.3 and foil-pitch amplitude of 15°-30°. Furthermore, increasing pitch amplitude with respect to power optimization increases the thrust slightly until pitch amplitude around 30°, and then the trust is increased notably with increasing of pitch amplitude. Additionally, the maximum mean thrust coefficient is computed of 2.67 and propulsive efficiency for this value is 42%. Based on the thrust optimization, the maximum propulsive efficiency is acquired 54% while the mean thrust coefficient is 2.18 at the same propulsive efficiency. Consequently, the maximum propulsive efficiency is obtained 77% and the appropriate Strouhal number, pitch amplitude and phase difference between heaving and pitching are calculated of 0.27, 31° and 77°, respectively.
Keywords: Flapping foil propulsion, Genetic algorithm, Micro Air Vehicle (MAV), Optimization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2155568 Study of Natural Convection Heat Transfer of Plate-Fin Heat Sink in a Closed Enclosure
Authors: Han-Taw Chen, Tzu-Hsiang Lin, Chung-Hou Lai
Abstract:
The present study applies the inverse method and three-dimensional CFD commercial software in conjunction with the experimental temperature data to investigate the heat transfer and fluid flow characteristics of the plate-fin heat sink in a rectangular closed enclosure. The inverse method with the finite difference method and the experimental temperature data is applied to determine the approximate heat transfer coefficient. Later, based on the obtained results, the zero-equation turbulence model is used to obtain the heat transfer and fluid flow characteristics between two fins. T0 validate the accuracy of the results obtained, the comparison of the heat transfer coefficient is made. The obtained temperature at selected measurement locations of the fin is also compared with experimental data. The effect of the height of the rectangular enclosure on the obtained results is discussed.Keywords: Inverse method, FLUENT, Plate-fin heat sink, Heat transfer characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2251567 A Simulation Model and Parametric Study of Triple-Effect Desalination Plant
Authors: Maha BenHamad, Ali Snoussi, Ammar Ben Brahim
Abstract:
A steady-state analysis of triple-effect thermal vapor compressor desalination unit was performed. A mathematical model based on mass, salinity and energy balances is developed. The purpose of this paper is to develop a connection between process simulator and process optimizer in order to study the influence of several operating variables on the performance and the produced water cost of the unit. A MATLAB program is used to solve the model equations, and Aspen HYSYS is used to model the plant. The model validity is examined against a commercial plant and showed a good agreement between industrial data and simulations results. Results show that the pressures of the last effect and the compressed vapor have an important influence on the produced cost, and the increase of the difference temperature in the condenser decreases the specific heat area about 22%.
Keywords: Steady-state, triple effect, thermal vapor compressor, MATLAB, Aspen HYSYS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1071566 A Comparison of Double Sided Friction Stir Welding in Air and Underwater for 6mm S275 Steel Plate
Authors: Philip Baillie, Stuart W. Campbell, Alexander M. Galloway, Stephen R. Cater, Norman A. McPherson
Abstract:
This study compared the mechanical and microstructural properties produced during friction stir welding (FSW) of S275 structural steel in air and underwater. Post weld tests assessed the tensile strength, micro-hardness, distortion, Charpy impact toughness and fatigue performance in each case. The study showed that there was no significant difference in the strength, hardness or fatigue life of the air and underwater specimens. However, Charpy impact toughness was shown to decrease for the underwater specimens and was attributed to a lower degree of recrystallization caused by the higher rate of heat loss experienced when welding underwater. Reduced angular and longitudinal distortion was observed in the underwater welded plate compared to the plate welded in air.
Keywords: Charpy impact toughness, distortion, fatigue, friction stir welding (FSW), micro-hardness, underwater.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2733