Search results for: Flow behavior
1837 Neutral to Earth Voltage Analysis in Harmonic Polluted Distribution Networks with Multi- Grounded Neutrals
Authors: G. Ahmadi, S.M. Shahrtash
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A multiphase harmonic load flow algorithm is developed based on backward/forward sweep to examine the effects of various factors on the neutral to earth voltage (NEV), including unsymmetrical system configuration, load unbalance and harmonic injection. The proposed algorithm composes fundamental frequency and harmonic frequencies power flows. The algorithm and the associated models are tested on IEEE 13 bus system. The magnitude of NEV is investigated under various conditions of the number of grounding rods per feeder lengths, the grounding rods resistance and the grounding resistance of the in feeding source. Additionally, the harmonic injection of nonlinear loads has been considered and its influences on NEV under different conditions are shown.
Keywords: NEV, Distribution System, Multi-grounded, Backward/Forward Sweep, Harmonic Analysis
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20561836 Equalization Algorithms for MIMO System
Authors: Said Elkassimi, Said Safi, B. Manaut
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In recent years, multi-antenna techniques are being considered as a potential solution to increase the flow of future wireless communication systems. The objective of this article is to study the emission and reception system MIMO (Multiple Input Multiple Output), and present the different reception decoding techniques. First we will present the least complex technical, linear receivers such as the zero forcing equalizer (ZF) and minimum mean squared error (MMSE). Then a nonlinear technique called ordered successive cancellation of interferences (OSIC) and the optimal detector based on the maximum likelihood criterion (ML), finally, we simulate the associated decoding algorithms for MIMO system such as ZF, MMSE, OSIC and ML, thus a comparison of performance of these algorithms in MIMO context.
Keywords: Multiple Input Multiple Outputs (MIMO), ZF, MMSE, Ordered Interference Successive Cancellation (OSIC), ML, Interference Successive Cancellation (SIC).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28271835 Static Modeling of the Delamination of a Composite Material Laminate in Mode II
Authors: Y. Madani, H. Achache, B. Boutabout
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The purpose of this paper is to analyze numerically by the three-dimensional finite element method, using ABAQUS calculation code, the mechanical behavior of a unidirectional and multidirectional delaminated stratified composite under mechanical loading in Mode II. This study consists of the determination of the energy release rate G in mode II as well as the distribution of equivalent von Mises stresses along the damaged zone by varying several parameters such as the applied load and the delamination length. It allowed us to deduce that the high energy release rate favors delamination at the free edges of a stratified plate subjected to bending.
Keywords: Delamination, energy release rate, finite element method, stratified composite.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7081834 Temporal Variation of Surface Runoff and Inter-Rill Erosion in Different Soil Textures of a Semi-Arid Region, Iran
Authors: Ali Reza Vaezi, Naser Fakori Ivand, Fereshteh Azarifam
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Inter-rill erosion is the detachment and transfer of soil particles between the rills which occurs due to the impact of raindrops and the shear stress of shallow surface runoff. This erosion can be affected by some soil properties such as texture, amount of organic matter and stability of soil aggregates. Information on the temporal variation of inter-rill erosion during a rainfall event and the effect of soil properties on it can help develop better methods to soil conservation in the hillslopes. The importance of this study is especially grate in semi-arid regions, where the soil is weakly aggregated and vegetation cover is mostly poor. Therefore, this research was conducted to investigate the temporal variation of surface flow and inter-rill erosion and the effect of soil properties on it in some semi-arid soils. A field experiment was done in eight different soil textures under simulated rainfalls with uniform intensity. A total of twenty four plots were installed for eight study soils with three replicates in the form of a random complete block design along the land. The plots were 1.2 m (length) × 1 m (width) in dimensions which designed with a distance of 3 m from each other across the slope. Then, soil samples were purred into the plots. Rainfall simulation experiments were done using a designed portable simulator with an intensity of 60 mm per hour for 60 minutes. Runoff production and soil loss were measured during 1 hour time with 5-min intervals. Soil properties including particle size distribution, aggregate stability, bulk density, exchangeable sodium percentages (ESP) and hydraulic conductivity (Ks) were determined in the soil samples. Correlation and regression analysis was done to determine the effect of soil properties on runoff and inter-rill erosion. Results indicated that the study soils have lower both organic matter content and aggregate stability. The soils, except for coarse textured textures, are calcareous and with relatively higher ESP. Runoff production and soil loss did not occur in sand texture, which was associated with higher infiltration and drainage rates. A strong relationship was found between inter-rill erosion and surface runoff (R2 = 0.75, p < 0.01). The correlation analysis showed that surface runoff was significantly affected by some soil properties consisting of sand, silt, clay, bulk density, gravel, Ks, lime (calcium carbonate), and ESP. The soils with lower Ks such as fine-textured soils, produced higher surface runoff and more inter-rill erosion. In the soils, surface runoff production temporally increased during rainfall and finally reached a peak after about 25-35 min. Time to peak was very short (30 min) in fine-textured soils, especially clay, which was related to their lower infiltration rate.
Keywords: Erosion plot, rainfall simulator, soil properties, surface flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 631833 The Application of Rhizophora Wood to Design: A Walking Stick for Elderly
Authors: Noppadon Sangwalpetch
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The objective of this research is to use Rhizophora wood to design a walking stick for elderly. The research was conducted by studying the behavior and the type of walking sticks used by 70 elderly aged between 60-80 years in Pragnamdaeng Sub-District, Samudsongkram Province. Questionnaires were used to collect data which were calculated to find percentage, mean, and standard deviation. The results are as follows: 1) most elderly use walking sticks due to the Osteoarthritis of the knees. 2) Most elderly need to use walking sticks because the walking sticks help to balance their positioning and prevent from stumble. 3) Most elderly agree that Rhizophora wood is suitable to make a walking stick because of its strength and toughness. 4) The design of the walking stick should be fine and practical with comfortable handle and the tip of the stick must not be slippery.
Keywords: Elderly, Product design, Rhizophora wood, Walking Stick.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20421832 Power Line Carrier Equipment Supporting IP Traffic Transmission in the Enterprise Networks of Energy Companies
Authors: M. S. Anton Merkulov
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This article discusses the questions concerning of creating small packet networks for energy companies with application of high voltage power line carrier equipment (PLC) with functionality of IP traffic transmission. The main idea is to create converged PLC links between substations and dispatching centers where packet data and voice are transmitted in one data flow. The article contents description of basic conception of the network, evaluation of voice traffic transmission parameters, and discussion of header compression techniques in relation to PLC links. The results of exploration show us, that convergent packet PLC links can be very useful in the construction of small packet networks between substations in remote locations, such as deposits or low populated areas.
Keywords: packet PLC, VoIP, time delay, packet traffic, overhead compression
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21641831 Development of Motor and Controller for VVA Module of Gasoline Vehicle
Authors: Joon Sung Park, Jun-Hyuk Choi, Jin-Hong Kim, In-Soung Jung
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Due to environmental concerns, the recent regulation on automobile fuel economy has been strengthened. The market demand for efficient vehicles is growing and automakers to improve engine fuel efficiency in the industry have been paying a lot of effort. To improve the fuel efficiency, it is necessary to reduce losses or to improve combustion efficiency of the engine. VVA (Variable Valve Actuation) technology enhances the engine's intake air flow, reduce pumping losses and mechanical friction losses. And also, VVA technology is the engine's low speed and high speed operation to implement each of appropriate valve lift. It improves the performance of engine in the entire operating range. This paper presents a design procedure of DC motor and drive for VVA system and shows the validity of the design result by experimental result with prototype.
Keywords: DC motor, Inverter, VVA, Electric Drive.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15931830 Relationships between Social Entrepreneurship, CSR and Social Innovation: In Theory and Practice
Authors: Krisztina Szegedi, Gyula Fülöp, Ádám Bereczk
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The shared goal of social entrepreneurship, corporate social responsibility and social innovation is the advancement of society. The business model of social enterprises is characterized by unique strategies based on the competencies of the entrepreneurs, and is not aimed primarily at the maximization of profits, but rather at carrying out goals for the benefit of society. Corporate social responsibility refers to the active behavior of a company, by which it can create new solutions to meet the needs of society, either on its own or in cooperation with other social stakeholders. The objectives of this article are to define concepts, describe and integrate relevant theoretical models, develop a model and introduce some examples of international practice that can inspire initiatives for social development.
Keywords: Corporate social responsibility, CSR, social innovation, social entrepreneurship.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41461829 Quantitative Study for Exchange of Gases from Open Sewer Channel to Atmosphere
Authors: Asif Mansoor, Nasiruddin Khan, Noreen Jamil
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In this communication a quantitative modeling approach is applied to construct model for the exchange of gases from open sewer channel to the atmosphere. The data for the exchange of gases of the open sewer channel for the year January 1979 to December 2006 is utilized for the construction of the model. The study reveals that stream flow of the open sewer channel exchanges the toxic gases continuously with time varying scale. We find that the quantitative modeling approach is more parsimonious model for these exchanges. The usual diagnostic tests are applied for the model adequacy. This model is beneficial for planner and managerial bodies for the improvement of implemented policies to overcome future environmental problems.Keywords: Open sewer channel, Industrial waste, Municipalwaste, Gases exchange, Atmosphere, Stochastic models, Diagnosticschecks.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15541828 Validation of a Fluid-Structure Interaction Model of an Aortic Dissection versus a Bench Top Model
Authors: K. Khanafer
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The aim of this investigation was to validate the fluid-structure interaction (FSI) model of type B aortic dissection with our experimental results from a bench-top-model. Another objective was to study the relationship between the size of a septectomy that increases the outflow of the false lumen and its effect on the values of the differential of pressure between true lumen and false lumen. FSI analysis based on Galerkin’s formulation was used in this investigation to study flow pattern and hemodynamics within a flexible type B aortic dissection model using boundary conditions from our experimental data. The numerical results of our model were verified against the experimental data for various tear size and location. Thus, CFD tools have a potential role in evaluating different scenarios and aortic dissection configurations.
Keywords: Aortic dissection, fluid-structure interaction, in vitro model, numerical.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9441827 Removal of Lead in High Rate Activated Sludge System
Authors: Mamdouh Y. Saleh, Gaber EL Enany, Medhat H. Elzahar, Mohamed Z. Elshikhipy, Rana Hamouda
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The heavy metals pollution in water, sediments and fish of Lake Manzala affected form the disposal of wastewater, industrial and agricultural drainage water into the lake on the environmental situation. A pilot plant with an industrial discharge flow of 135L/h designed according to the activated sludge plant to simulate between the biological and chemical treatment with the addition of alum to the aeration tank with dosages of 100, 150, 200 and 250 mg/L. The industrial discharge had concentrations of Lead and BOD5 with an average range 1.22, 145mg/L respectively. That means the average Pb was high up to 25 times than the allowed permissible concentration. The optimization of the chemical-biological process using 200mg/L Alum dosage compared has improvement of Lead and BOD5 removal efficiency to 61.76% and 56% respectively.
Keywords: Industrial wastewater, Activated sludge, BOD5, Lead, Alum salt.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25721826 Managing a Manufacturing System with Integration of Walking Worker and Lean Thinking
Authors: Said Rabah Azzam, Laura Carolina Arias, Shikun Zhou
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A product goes through various processes in a production flow which is also known as assembly line in manufacturing process management. Toyota created a new concept which is known as lean concept in manufacturing industry. Today it is the leading model in manufacturing plants through the globe. The linear walking worker assembly line is a flexible assembly system where each worker travels down the line carrying out each assembly task at each station; and each worker accomplishes the assembly of a unit from start to finish. This paper attempts to combine the flexibility of the walking worker and lean in order to quantify the benefits from applying the shop floor principles of lean management.
Keywords: Toyota Production System, TPS, LeanManufacturing, Walking Worker, Lean Management, Management, Linear Assembly Lines, U-shaped Assembly Lines, Shop FloorManagement
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18221825 Incorporation of Long-Term Redundancy in ECG Time Domain Compression Methods through Curve Simplification and Block-Sorting
Authors: Bachir Boucheham, Youcef Ferdi, Mohamed Chaouki Batouche
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We suggest a novel method to incorporate longterm redundancy (LTR) in signal time domain compression methods. The proposition is based on block-sorting and curve simplification. The proposition is illustrated on the ECG signal as a post-processor for the FAN method. Test applications on the new so-obtained FAN+ method using the MIT-BIH database show substantial improvement of the compression ratio-distortion behavior for a higher quality reconstructed signal.Keywords: ECG compression, Long-term redundancy, Block-sorting, Curve Simplification.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15201824 Influence of Flame-Holder on Existence Important Parameters in a Duct Combustion Simulator
Authors: M. M. Doustdar, M. Mojtahedpoor
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The effects of flame-holder position, the ratio of flame holder diameter to combustion chamber diameter and injection angle on fuel propulsive droplets sizing and effective mass fraction have been studied by a cold flow. We named the mass of fuel vapor inside the flammability limit as the effective mass fraction. An empty cylinder as well as a flame-holder which are a simulator for duct combustion has been considered. The airflow comes into the cylinder from one side and injection operation will be done by four nozzles which are located on the entrance of cylinder. To fulfill the calculations a modified version of KIVA-3V code which is a transient, three-dimensional, multiphase, multi component code for the analysis of chemically reacting flows with sprays, is used.Keywords: KIVA-3V, flame-holder, duct combustion, effective mass fraction, mean diameter of droplets.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17421823 A Performance Evaluation of Oscillation Based Test in Continuous Time Filters
Authors: Eduardo Romero, Marcelo Costamagna, Gabriela Peretti, Carlos Marqués
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This work evaluates the ability of OBT for detecting parametric faults in continuous-time filters. To this end, we adopt two filters with quite different topologies as cases of study and a previously reported statistical fault model. In addition, we explore the behavior of the test schemes when a particular test condition is changed. The new data reported here, obtained from a fault simulation process, reveal a lower performance of OBT not observed in previous work using single-deviation faults, even under the change in the test condition.
Keywords: Testing, analog fault simulation, analog filter test, oscillation based test.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14431822 Lightweight High-Pressure Ratio Centrifugal Compressor for Vehicles-Investigation of Pipe Diffuser Designs by Means of CFD
Authors: Eleni Ioannou, Pascal Nucara, Keith Pullen
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The subject of this paper is the investigation of the best efficiency design of a compressor diffuser applied in new lightweight, ultra efficient micro-gas turbine engines for vehicles. The Computational Fluid Dynamics (CFD) results are obtained utilizing steady state simulations for a wedge and an ”oval” type pipe diffuser in an effort to identify the beneficial effects of the pipe diffuser design. The basic flow features are presented with particular focus on the optimization of the pipe diffuser leading to higher efficiencies for the compressor stage. The optimised pipe diffuser is designed to exploit the 3D freedom enabled by Selective Laser Melting, hence purposely involves an investigation of geometric characteristics that do not follow the traditional diffuser concept.Keywords: CFD, centrifugal compressor, micro-gas turbine, pipe diffuser, SLM, wedge diffuser.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19271821 A Study on Changing of Energy-Saving Performance of GHP Air Conditioning System with Time-Series Variation
Authors: Ying Xin, Shigeki Kametani
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This paper deals the energy saving performance of GHP (Gas engine heat pump) air conditioning system has improved with time-series variation. There are two types of air conditioning systems, VRF (Variable refrigerant flow) and central cooling and heating system. VRF is classified as EHP (Electric driven heat pump) and GHP. EHP drives the compressor with electric motor. GHP drives the compressor with the gas engine. The electric consumption of GHP is less than one tenth of EHP does.
In this study, the energy consumption data of GHP installed the junior high schools was collected. An annual and monthly energy consumption per rated thermal output power of each apparatus was calculated, and then their energy efficiency was analyzed. From these data, we investigated improvement of the energy saving of the GHP air conditioning system by the change in the generation.
Keywords: Energy-saving, VRF, GHP, EHP, Air Conditioning System.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18821820 Liquid Fuel Production via Catalytic Pyrolysis of Waste Oil
Authors: Malee Santikunaporn, Neera Wongtyanuwat, Channarong Asavatesanupap
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Pyrolysis of waste oil is an effective process to produce high quality liquid fuels. In this work, pyrolysis experiments of waste oil over Y zeolite were carried out in a semi-batch reactor under a flow of nitrogen at atmospheric pressure and at different reaction temperatures (350-450 oC). The products were gas, liquid fuel, and residue. Only liquid fuel was further characterized for its composition and properties by using gas chromatography, thermogravimetric analyzer, and bomb calorimeter. Experimental results indicated that the pyrolysis reaction temperature significantly affected both yield and composition distribution of pyrolysis oil. An increase in reaction temperature resulted in increased fuel yield, especially gasoline fraction. To obtain high amount of fuel, the optimal reaction temperature should be higher than 350 oC. A presence of Y zeolite in the system enhanced the cracking activity. In addition, the pyrolysis oil yield is proportional to the catalyst quantity.
Keywords: Waste oil, pyrolysis oil, Y zeolite, gasoline, diesel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8041819 Hardware Description Language Design of Σ-Δ Fractional-N Phase-Locked Loop for Wireless Applications
Authors: Ahmed El Oualkadi, Abdellah Ait Ouahman
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This paper discusses a systematic design of a Σ-Δ fractional-N Phase-Locked Loop based on HDL behavioral modeling. The proposed design consists in describing the mixed behavior of this PLL architecture starting from the specifications of each building block. The HDL models of critical PLL blocks have been described in VHDL-AMS to predict the different specifications of the PLL. The effect of different noise sources has been efficiently introduced to study the PLL system performances. The obtained results are compared with transistor-level simulations to validate the effectiveness of the proposed models for wireless applications in the frequency range around 2.45 GHz.
Keywords: Phase-locked loop, frequency synthesizer, fractional-N PLL, Σ-Δ modulator, HDL models
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37771818 Voltage Stability Enhancement Using Cat Swarm Optimization Algorithm
Authors: P. Suryakumari, P. Kantarao
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Optimal Power Flow (OPF) problem in electrical power system is considered as a static, non-linear, multi-objective or a single objective optimization problem. This paper presents an algorithm for solving the voltage stability objective reactive power dispatch problem in a power system .The proposed approach employs cat swarm optimization algorithm for optimal settings of RPD control variables. Generator terminal voltages, reactive power generation of the capacitor banks and tap changing transformer setting are taken as the optimization variables. CSO algorithm is tested on standard IEEE 30 bus system and the results are compared with other methods to prove the effectiveness of the new algorithm. As a result, the proposed method is the best for solving optimal reactive power dispatch problem.
Keywords: RPD problem, voltage stability enhancement, CSO algorithm.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24361817 Effects of Position and Shape of Atomic Defects on the Band Gap of Graphene Nano Ribbon Superlattices
Authors: Zeinab Jokar, Mohammad Reza Moslemi
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In this work, we study the behavior of introducing atomic size vacancy in a graphene nanoribbon superlattice. Our investigations are based on the density functional theory (DFT) with the Local Density Approximation in Atomistix Toolkit (ATK). We show that, in addition to its shape, the position of vacancy has a major impact on the electrical properties of a graphene nanoribbon superlattice. We show that the band gap of an armchair graphene nanoribbon may be tuned by introducing an appropriate periodic pattern of vacancies. The band gap changes in a zig-zag manner similar to the variation of band gap of a graphene nanoribbon by changing its width.
Keywords: Antidot, Atomistix ToolKit, Superlattice, Vacancy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27031816 Solutions for Comfort and Safety on Vibrations Resulting from the Action of the Wind on the Building in the Form of Portico with Four Floors
Authors: G. B. M. Carvalho, V. A. C. Vale, E. T. L. Cöuras Ford
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With the aim of increasing the levels of comfort and security structures, the study of dynamic loads on buildings has been one of the focuses in the area of control engineering, civil engineering and architecture. Thus, this work presents a study based on simulation of the dynamics of buildings in the form of portico subjected to wind action, besides presenting an action of passive control, using for this the dynamics of the structure, consequently representing a system appropriated on environmental issues. These control systems are named the dynamic vibration absorbers.
Keywords: Dynamic vibration absorber, structure, comfort, safety, wind behavior, structure.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7671815 Korean Men’s Interest in Gonzo Pornography and Use of Condoms
Authors: Chyng Sun
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This brief report examines correlations between Korean men’s interest in gonzo pornography, perceptions of pornography’s functional value, and use of condoms. The report found that, neither a higher interest in gonzo or the perception that pornography is a source of sexual information was directly related to condom utilization. However, interest in gonzo pornography interacted with pornography perceptions to predict condomless sex. The findings suggest that Korean men who 1) had higher interest in viewing gonzo pornography, and 2) had a tendency to view pornography as a source of sexual information, are more likely to have sex without condoms. That is, when viewers consider pornography to be a form of sexual education, they are more likely to use the learned pornographic script to inform their sexual behavior.Keywords: Korean, male, pornography, sexuality.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11921814 Structural Performance of a Timber-Concrete Bridge Prototype
Authors: Pedro Gutemberg de Alcântara Segundinho, José Antonio Matthiesen, Marcelo Rodrigo Carreira
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Timber-concrete structures were recently introduced in Brazil as a viable option for bridge construction on side roads. Binding between timber and concrete is fundamentally important to assure the rigidity and performance of this structural system. The objective of this study was to assess the structural performance of a timber-concrete bridge prototype with width of 170cm and span of 400cm, whose binding among timber beams and concrete slabs was made with metal pins, obtained from CA 50 construction steel bars of 12.5mm diameter. It was possible to conclude, from the results obtained experimentally in laboratory, that the timber-concrete bridge prototype showed a good structural performance. This structural system provides an economical, rapid implementation solution, which may be used on side roads, favoring regional integration and agricultural production flow.
Keywords: Binding, bridge prototype, timber and concrete
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21421813 Mechanism and Kinetic of Layers Growth: Application to Nitriding of 32CrMoV13 Steel
Authors: L. Torchane
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In this work, our goal is to optimize the nitriding treatment at a low-temperature of the steel 32CrMoV13 using gas mixtures of ammonia, nitrogen and hydrogen to improve the mechanical properties of the surface (good wear resistance, friction and corrosion), and of the diffusion layer of the nitrogen (good resistance to fatigue and good tenacity with heart). By limiting our work to the pure iron and to the alloys iron-chromium and iron-chromium-carbon, we have studied the various parameters which manage the nitriding: flow rate and composition of the gaseous phase, the interaction chromium-nitrogen and chromium-carbon by the help of experiments of nitriding realized in the laboratory by thermogravimetry. The acquired knowledge has been applied by the mastery of the growth of the γ' combination layer on the α diffusion layer in the case of the industrial steel 32CrMoV13.Keywords: Diffusion of nitrogen, Gaseous nitriding, Layer growth kinetic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15841812 PZ: A Z-based Formalism for Modeling Probabilistic Behavior
Authors: Hassan Haghighi
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Probabilistic techniques in computer programs are becoming more and more widely used. Therefore, there is a big interest in the formal specification, verification, and development of probabilistic programs. In our work-in-progress project, we are attempting to make a constructive framework for developing probabilistic programs formally. The main contribution of this paper is to introduce an intermediate artifact of our work, a Z-based formalism called PZ, by which one can build set theoretical models of probabilistic programs. We propose to use a constructive set theory, called CZ set theory, to interpret the specifications written in PZ. Since CZ has an interpretation in Martin-L¨of-s theory of types, this idea enables us to derive probabilistic programs from correctness proofs of their PZ specifications.Keywords: formal specification, formal program development, probabilistic programs, CZ set theory, type theory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12021811 Designing a Low Speed Wind Tunnel for Investigating Effects of Blockage Ratio on Heat Transfer of a Non-Circular Tube
Authors: Arash Mirabdolah Lavasani, Taher Maarefdoost
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Effect of blockage ratio on heat transfer from non-circular tube is studied experimentally. For doing this experiment a suction type low speed wind tunnel with test section dimension of 14×14×40 and velocity in rage of 7-20 m/s was designed. The blockage ratios varied between 1.5 to 7 and Reynolds number based on equivalent diameter varies in range of 7.5×103 to 17.5×103. The results show that by increasing blockage ratio from 1.5 to 7, drag coefficient of the cam shaped tube decreased about 55 percent. By increasing Reynolds number, Nusselt number of the cam shaped tube increases about 40 to 48 percent in all ranges of blockage ratios.
Keywords: Wind tunnel, non-circular tube, blockage ratio, experimental heat transfer, cross-flow.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26291810 Design Alternatives for Lateral Force-Resisting Systems of Tall Buildings in Dubai, UAE
Authors: Mohammad AlHamaydeh, Sherif Yehia, Nader Aly, Ammar Douba, Layane Hamzeh
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Four design alternatives for lateral force-resisting systems of tall buildings in Dubai, UAE are presented. Quantitative comparisons between the different designs are also made. This paper is intended to provide different feasible lateral systems to be used in Dubai in light of the available seismic hazard studies of the UAE. The different lateral systems are chosen in conformance with the International Building Code (IBC). Moreover, the expected behavior of each system is highlighted and light is shed on some of the cost implications associated with lateral system selection.Keywords: Concrete, Dual, Dubai UAE Seismicity, Special Moment-Resisting Frames (SMRF), Special Shear Wall, Steel
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35231809 Dynamics, Hierarchy and Commensalities: A Study of Inter Caste Relationship in a North Indian Village
Authors: K. Pandey
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The present study is a functional analysis of the relationship between castes which indicates the dynamics of the caste structure in the rural setting. The researcher has tried to show both the cooperation and competition on important ceremonial and social occasions. The real India exists in the villages, so we need to know about their solidarity and also what the village life is and has been shaping into. We need to emphasize a microcosmic study of Indian rural life. Furthermore, caste integration is an acute problem country faces today. To resolve this we are required to know the dynamics of behavior of the people of different castes and for the study of the caste dynamics a study of caste relations are needed. The present study is an attempt in this direction.Keywords: Hierarchial groups, jajmani system, functional dependence, commensalities.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27271808 Preliminary Study of Desiccant Cooling System under Algerian Climates
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The interest in air conditioning using renewable energies is increasing. The thermal energy produced from the solar energy can be converted to useful cooling and heating through the thermochemical or thermophysical processes by using thermally activated energy conversion systems. The ambient air contains so much water that very high dehumidification rates are required. For a continuous dehumidification of the process air, the water adsorbed on the desiccant material has to be removed, which is done by allowing hot air to flow through the desiccant material (regeneration). A solid desiccant cooling system transfers moisture from the inlet air to the silica gel by using two processes: Absorption process and the regeneration process. The main aim of this paper is to study how the dehumidification rate, the generation temperature and many other factors influence the efficiency of a solid desiccant system by using TRNSYS software. The results show that the desiccant system could be used to decrease the humidity rate of the entering air.Keywords: Dehumidification, efficiency, humidity, TRNSYS.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 882