Search results for: Turkish army forces
791 Study of Mechanical Behavior of Unidirectional Composite Laminates According
Authors: Deliou Adel, Saadalah Younes, Belkaid Khmissi, Dehbi Meriem
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Composite materials, in the most common sense of the term, are a set of synthetic materials designed and used mainly for structural applications; the mechanical function is dominant. The mechanical behaviors of the composite, as well as the degradation mechanisms leading to its rupture, depend on the nature of the constituents and on the architecture of the fiber preform. The profile is required because it guides the engineer in designing structures with precise properties in relation to the needs. This work is about studying the mechanical behavior of unidirectional composite laminates according to different failure criteria. Varying strength parameter values make it possible to compare the ultimate mechanical characteristics obtained by the criteria of Tsai-Hill, Fisher and maximum stress. The laminate is subjected to uniaxial tensile membrane forces. Estimates of their ultimate strengths and the plotting of the failure envelope constitute the principal axis of this study. Using the theory of maximum stress, we can determine the various modes of damage of the composite. The different components of the deformation are presented for different orientations of fibers.Keywords: unidirectional kevlar/epoxy composite, failure criterion, membrane stress, deformations, failure envelope
Procedia PDF Downloads 88790 Analysis of the Suspension Rocker of Formula SAE Prototype by Finite Element Method
Authors: Jessyca A. Bessa, Darlan A. Barroso, Jonas P. Reges, Auzuir R. Alexandria
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This work aims to study the rocker. This is a device of the suspension of Formula SAE vehicle that receives efforts from the motion scrolling of the vehicle and transmits them to the chassis frame minimized by a momentum ratio and smoothed by the set spring - damper. A review of parameters used in vehicle dynamics and a geometric analysis of the forces and stresses caused by such was carried out. The main function of the rocker is to reduce the force transmitted to the frame due to movement of rolling and subsequent application of the suspension. This functions is taken as satisfactory, since the force applied to the wheel and which would be transmitted to the chassis is reduced from 3833.9N to 3496.48N. From these values can be further more detailed simulations using the finite element method aimed at mass reduction or even rocker manufacturing feasibility aluminum. Then, the analysis by the finite element method was applied. This analysis uses the theory of discretization of systems and examines the strength of the component based on the distortion energy, determining the maximum straining experienced by the component and the region of higher demand.Keywords: rocker, suspension, the finite element method, mechatronics engineering
Procedia PDF Downloads 541789 A Simple Approach for the Analysis of First Vibration Mode of Layered Soil Profiles
Authors: Haizhong Zhang, Yan-Gang Zhao
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Fundamental period, mode shape, and participation factor are important basic information for the understanding of earthquake response of ground. In this study, a simple approach is presented to calculate these basic information of layered soil profiles. To develop this method, closed form equations are derived for analysis of free vibration of layered soil profiles firstly, based on equilibrium between inertia and elastic forces. Then, by further associating with the Madera procedure developed for estimation of fundamental period, a simple method that can directly determine the fundamental period, mode shape and participation factor is proposed. The proposed approach can be conveniently implemented in simple spreadsheets and easily used by practicing engineers. In addition, the accuracy of the proposed approach is investigated by analyzing first vibration mode of 67 representative layered soil profiles, it is found that results by the proposed method agree very well with accurate results.Keywords: layered soil profile, natural vibration, fundamental period, fundamental mode shape
Procedia PDF Downloads 326788 Autonomous Rendezvous for Underactuated Spacecraft
Authors: Espen Oland
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This paper presents a solution to the problem of autonomous rendezvous for spacecraft equipped with one main thruster for translational control and three reaction wheels for rotational control. With fewer actuators than degrees of freedom, this constitutes an underactuated control problem, requiring a coupling between the translational and rotational dynamics to facilitate control. This paper shows how to obtain this coupling, and applies the results to autonomous rendezvous between a follower spacecraft and a leader spacecraft. Additionally, since the thrust is constrained between zero and an upper bound, no negative forces can be generated to slow down the speed of the spacecraft. A combined speed and attitude control logic is therefore created that can be divided into three main phases: 1) The orbital velocity vector is pointed towards the desired position and the thrust is used to obtain the desired speed, 2) during the coasting phase, the attitude is changed to facilitate deceleration using the main thruster, 3) the speed is decreased as the spacecraft reaches its desired position. The results are validated through simulations, showing the capabilities of the proposed approach.Keywords: attitude control, spacecraft rendezvous, translational control, underactuated rigid body
Procedia PDF Downloads 292787 Investigation of Dynamic Characteristic of Planetary Gear Set Based On Three-Axes Torque Measurement
Authors: Masao Nakagawa, Toshiki Hirogaki, Eiichi Aoyama, Mohamed Ali Ben Abbes
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A planetary gear set is widely used in hybrid vehicles as the power distribution system or in electric vehicles as the high reduction system, but due to its complexity with planet gears, its dynamic characteristic is not fully understood. There are many reports on two-axes driving or displacement of the planet gears under these conditions, but only few reports deal with three-axes driving. A three-axes driving condition is tested using three-axes torque measurement and focuses on the dynamic characteristic around the planet gears in this report. From experimental result, it was confirmed that the transition forces around the planet gears were balanced and the torques were also balanced around the instantaneous rotation center. The meshing frequency under these conditions was revealed to be the harmonics of two meshing frequencies; meshing frequency of the ring gear and that of the planet gears. The input power of the ring gear is distributed to the carrier and the sun gear in the dynamic sequential change of three fixed conditions; planet, star and solar modes.Keywords: dynamic characteristic, gear, planetary gear set, torque measuring
Procedia PDF Downloads 381786 Intellectual Capital Disclosure: A Study of Australia and Sri Lanka
Authors: Puwanenthiren Pratheepkanth
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This study considers whether national development level influences a firm’s voluntary intellectual capital disclosure (ICD) provided by a sample of 100 Australian and 100 Sri Lankan firms in terms of a two-years during 2015-16. This two-nation study uses a content analysis and literature-review analysis to provide an understanding of the underlying forces and issues. It was found that Australian firms tend to rely heavily on external structure disclosures (with particular attention to brands, customer loyalty, and research collaborations), but Sri Lankan relatively larger firms prefer intellectual property disclosures and the smaller firms tend to be as adept at external structure as their Australian counterparts. It was also found that the nature of a firm tends to trump the nurture of the development level of the country in which the firm is embedded. While a wider diffusion of better ICD methodology under International Financial Reporting Standard (IFRS) could improve the cost-effectiveness of financial reporting and generally increase efficiency, this is unlikely to occur until competition is more of a spur.Keywords: developed countries, developing countries, content analysis, intellectual capital disclosure
Procedia PDF Downloads 170785 Rotor Dynamic Analysis for a Shaft Train by Using Finite Element Method
Authors: M. Najafi
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In the present paper, a large turbo-generator shaft train including a heavy-duty gas turbine engine, a coupling, and a generator is established. The method of analysis is based on finite element simplified model for lateral and torsional vibration calculation. The basic elements of rotor are the shafts and the disks which are represented as circular cross section flexible beams and rigid body elements, respectively. For more accurate results, the gyroscopic effect and bearing dynamics coefficients and function of rotation are taken into account, and for the influence of shear effect, rotor has been modeled in the form of Timoshenko beam. Lateral critical speeds, critical speed map, damped mode shapes, Campbell diagram, zones of instability, amplitudes, phase angles response due to synchronous forces of excitation and amplification factor are calculated. Also, in the present paper, the effect of imbalanced rotor and effects of changing in internal force and temperature are studied.Keywords: rotor dynamic analysis, finite element method, shaft train, Campbell diagram
Procedia PDF Downloads 136784 Wind Interference Effects on Various Plan Shape Buildings Under Wind Load
Authors: Ritu Raj, Hrishikesh Dubey
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This paper presents the results of the experimental investigations carried out on two intricate plan shaped buildings to evaluate aerodynamic performance of the building. The purpose is to study the associated environment arising due to wind forces in isolated and interference conditions on a model of scale 1:300 with a prototype having 180m height. Experimental tests were carried out at the boundary layer wind tunnel considering isolated conditions with 0° to 180° isolated wind directions and four interference conditions of twin building (separately for both the models). The research has been undertaken in Terrain Category-II, which is the most widely available terrain in India. A comparative assessment of the two models is performed out in an attempt to comprehend the various consequences of diverse conditions that may emerge in real-life situations, as well as the discrepancies amongst them. Experimental results of wind pressure coefficients of Model-1 and Model-2 shows good agreement with various wind incidence conditions with minute difference in the magnitudes of mean Cp. On the basis of wind tunnel studies, it is distinguished that the performance of Model-2 is better than Model-1in both isolated as well as interference conditions for all wind incidences and orientations respectively.Keywords: interference factor, tall buildings, wind direction, mean pressure-coefficients
Procedia PDF Downloads 128783 Media Response to Kashmir Conflict: How Press Differed in Highlighting Protest Shutdowns between 1990-2010
Authors: Danish Gadda
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Kashmir has been a bleeding-spot in the South Asian politics since 1947 when the subcontinent was bifurcated into Hindu, India and Muslim Pakistan by the departing British colonisers. Kashmir couldn’t accede to either of the two new-born, sovereign nations until tribal invasion from Pakistan forced an unfortunate change of events. India, driven by conditional accession signed by the Kashmir’s last monarch, sent its army to defend Kashmir Valley, with a promise, made subsequently, that the region’s fate would be decided by the natives through an internationally-monitored plebiscite. The country, however, broke its promise, choosing not to withdraw its military to allow the plebiscite, and, instead, strengthened its claim over Kashmir, which it later started describing as her integral part. War, fought in the shape of three and a half bloody battles, ensued between India and Pakistan, even as the United Nations’ intervention managed a ceasefire as early as in the 1950s, though not before Kashmir had come to be divided into its India-controlled and Pakistan-controlled halves. Prolonged, the dispute over Kashmir took a violent turn in 1989-90 with the start of an anti-India armed rebellion. Kashmiris have been fighting for their right to self-determination, and bringing their own life to a grinding halt has been one of their preferred forms of protest against the Indian rule. This form of resistance is locally called ‘Hartals’, and recognised as shutdowns, which have often been prolonged and violent. Since 1989-90, the shutdowns have become only more frequent and forceful, and there are marked days on which Kashmir shuts down in protest every year, like a ritual. This paper is based on a study of how the Indian and Kashmir press covered the shutdowns observed in the troubled valley on four such days: January 26 (Indian Republic Day), February 11 (the day on which India executed a prominent Kashmiri resistance leader), August 15 (India’s Independence Day), and October 27 (the day on which the Indian military has landed in Kashmir). The coverage given by the Indian and Kashmiri press to the shutdowns observed on these days has been studied using the multi-tier content analysis approach: 1) Difference in the number of shutdowns covered by the two section is looked at, 2) the placement of the stories in the two section of the press is analysed, 3) the discourse highlighted by the two section of the press is compared, and 4) the editorials written by the two section of the press about the shutdowns are analysed. The findings show the Indian and the local press have been focussing on the two, predictable extremes of the situation: the Indian press has favoured the state, while the Kashmir or the local press has focussed on the narrative opposing the state’s. The difference is noticed in the quantitative as well as the qualitative aspects of their coverage.Keywords: Indo-Pak tension, Kashmir conflict, protest shutdowns, South-Asian politics
Procedia PDF Downloads 232782 Managing and Marketing a Modern Art Museum in a Small Town: A Case Study on Odunpazarı Modern Museum
Authors: Mehmet Sinan Erguven
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Modern art is relatively new but a popular area in Turkish art society. Modern art museums are mainly located in big cities like Istanbul and Ankara where cultural life is more dynamic. Odunpazarı Modern Museum (OMM) will open its doors on September 2019 and be the only modern art museum located in a small town in Turkey. OMM executives declare the mission of the museum as; art must go beyond the metropolises of the world, give a new lease of life to cities that make a difference with their cultural texture, and reach a greater audience through that expansion. So OMM will not only serve as a museum but a landmark for regenerating the city brand of Eskişehir like the Guggenheim in Bilbao. OMM is located in the Odunpazarı area, the heart of Eskişehir. Named after the historical timber market it once hosted, Odunpazarı is a nominated site for the UNESCO Intangible Cultural Heritage List, and is Eskişehir’s first area of settlement. This study focuses on the complex nature of opening a modern art museum in a small town. The management and marketing dynamics of OMM are discussed in the study. Content analysis technique is used on local and national news to display the perception differences before and after the opening of OMM. In depth interviews with the executives of the museum are conducted in order to enlighten the insights of opening a modern art museum in a small town. Early findings of the content analysis point out that, the comments on the national press are mostly positive. On the other hand, different views occur on the local press. The location OMM is constructed and grandness of the museum building are criticized by some of the local newspapers. OMM’s potential as a tourist attraction is agreed by most of the media. OMM executives stated the most challenging task as reaching the different target audiences on international, national and local levels. These early findings will be improved and compared shortly before and after the opening of the museum.Keywords: management, marketing, Odunpazarı modern museum, small town
Procedia PDF Downloads 231781 Effect of Vegetable Oil Based Nanofluids on Machining Performance: An Experimental Investigation
Authors: Krishna Mohana Rao Gurram, R. Padmini, P. Vamsi Krishna
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As a part of extensive research for ecologically safe and operator friendly cutting fluids, this paper presents the experimental investigations on the performance of eco-friendly vegetable oil based nanofluids in turning operation. In order to assess the quality of nano cutting fluids used during machining, cutting temperatures, cutting forces and surface roughness under constant cutting conditions are measured. The influence of two types of nanofluids prepared from nano boric acid and CNT particles mixed separately with coconut oil, on machining performance during turning operation is examined. Comparative analysis of the results obtained is done under dry and lubricant environments. Results obtained using cutting fluids prepared from vegetable oil based nanofluids are encouraging and more pronouncing by the application of CCCNT at machining zone. The extent of improvement in reduction of cutting temperatures, main cutting force, tool wear and surface roughness is tracked to be 13%, 37.5%, 44% and 40% respectively by the application of CCCNT compared to dry machining.Keywords: nanoparticles, vegetable oil, machining, MQL, surface roughness
Procedia PDF Downloads 359780 English Language Teaching Graduate Students' Use of Discussion Moves in Research Articles
Authors: Gamzegul Koca, Evrim Eveyik-Aydin
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Genre and discipline-specific knowledge of academic discourse in writing has long been acknowledged as being a core skill to achieve formidable tasks that are expected of graduate students in academic settings. Genre analysis approaches can be adopted to unveil the challenges encountered in these tasks to be able to take instructional actions addressing the aspects of graduate writing that need improvement. In an attempt to find genre-specific academic writing needs of Turkish students enrolled in a graduate program in ELT, this study examines the rhetorical structure of discussion sections of research articles written during the course load stage of their graduate studies. The 35.437-word specialized corpus of graduate papers compiled for the purpose of the study includes discussions of 58 unpublished reports of empirical studies, 31 written in MA courses and 27 in Ph.D. courses by a total of 44 graduate students. The study does sentence-based move structure analysis using the framework developed by Eveyik-Aydın, Karabacak and Akyel in a corpus-based study that analyzed the discussion moves of expert writers in published articles in ELT journals indexed by Social Sciences Citation. The coding of 1577 sentences by three graders using this framework revealed that while the graduate papers included the same moves used in published articles, the rhetorical structure of MA and Ph.D. papers showed considerable differences in terms of the frequency of occurrence of main discussion moves, including interpretation of the results and drawing implications. The implications of these findings will be discussed with respect to the needs of graduate writers and the expectations of discourse community.Keywords: discussion moves, genre-specific rhetorical structure, move analysis, research articles, the specialized corpus of graduate papers
Procedia PDF Downloads 166779 The Characteristcs and Amino Acid Profile of Edible Coating Extracted from Pigskin Gelatin
Authors: Meity Sompie, Agnes Triasih, Wisje Ponto
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Edible coating is thin layers that act as a barrier to the external factors and protect the food products. The addition of the plasticizer to the edible coating is required to overcome film caused by extensive intermolecular forces. The potential development of pigskin with different ages as a raw material for the manufacture of edible films had not been widely publicized. This research was aimed to determine the influence of gelatin concentration and different type of plasticizer on the edible coating characteristics extracted from pigskin gelatin. This study used Completely Randomized Design (CRD) with two factors and three replicates of treatments. The first factor was consisted of pigskin gelatin concentration ( 10, 20, and 30 %) and the second factor was different type of plasticizer (glycerol, sorbitol and PEG). The results show that the interaction between the use of gelatin concentrations and type of plasticizer had significant effect (P< 0.05) on the thickness, tensile strength, elongation, water vapor transmission rate (WVTR), water content and amino acid profile of edible coating. It was concluded that the edible coating from pigskin gelatin with plasticizer gliserol had the best film characteristics, and it can be applied as an edible coating.Keywords: edible coating, edible film, pigskin gelatin, plasticizer
Procedia PDF Downloads 214778 Macroalgae as a Gaseous Fuel Option: Potential and Advanced Conversion Technologies
Authors: Muhammad Rizwan Tabassum, Ao Xia, Jerry D. Murphy
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The aim of this work is to provide an overview of macroalgae as an alternative feedstock for gaseous fuel production and key innovative technologies. Climate change and continuously depleting resources are the key driving forces to think for alternative sources of energy. Macroalgae can be favored over land based energy crops because they are not in direct competition with food crops. However, some drawbacks, such as high moisture content, seasonal variation in chemical composition and process inhibition limit the economic practicability. Macroalgae, like brown seaweed can be converted into gaseous and liquid fuel by different conversion technologies. Biomethane via anaerobic digestion is the appealing technology due to its dual advantage of a commercially applicable and environment friendly technology. Other technologies like biodiesel and bioethanol conversion technologies from seaweed are still under progress. Screening of high yielding macroalgae species, peak harvesting season and process optimization make the technology economically feasible for alternative source of feedstock for biofuel production in future.Keywords: anaerobic digestion, biofuels, bio-methane, advanced conversion technologies, macroalgae
Procedia PDF Downloads 307777 Computational Fluid Dynamics Analysis and Optimization of the Coanda Unmanned Aerial Vehicle Platform
Authors: Nigel Q. Kelly, Zaid Siddiqi, Jin W. Lee
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It is known that using Coanda aerosurfaces can drastically augment the lift forces when applied to an Unmanned Aerial Vehicle (UAV) platform. However, Coanda saucer UAVs, which commonly use a dish-like, radially-extending structure, have shown no significant increases in thrust/lift force and therefore have never been commercially successful: the additional thrust/lift generated by the Coanda surface diminishes since the airstreams emerging from the rotor compartment expand radially causing serious loss of momentums and therefore a net loss of total thrust/lift. To overcome this technical weakness, we propose to examine a Coanda surface of straight, cylindrical design and optimize its geometry for highest thrust/lift utilizing computational fluid dynamics software ANSYS Fluent®. The results of this study reveal that a Coanda UAV configured with 4 sides of straight, cylindrical Coanda surface achieve an overall 45% increase in lift compared to conventional Coanda Saucer UAV configurations. This venture integrates with an ongoing research project where a Coanda prototype is being assembled. Additionally, a custom thrust-stand has been constructed for thrust/lift measurement.Keywords: CFD, Coanda, lift, UAV
Procedia PDF Downloads 141776 Econophysical Approach on Predictability of Financial Crisis: The 2001 Crisis of Turkey and Argentina Case
Authors: Arzu K. Kamberli, Tolga Ulusoy
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Technological developments and the resulting global communication have made the 21st century when large capitals are moved from one end to the other via a button. As a result, the flow of capital inflows has accelerated, and capital inflow has brought with it crisis-related infectiousness. Considering the irrational human behavior, the financial crisis in the world under the influence of the whole world has turned into the basic problem of the countries and increased the interest of the researchers in the reasons of the crisis and the period in which they lived. Therefore, the complex nature of the financial crises and its linearly unexplained structure have also been included in the new discipline, econophysics. As it is known, although financial crises have prediction mechanisms, there is no definite information. In this context, in this study, using the concept of electric field from the electrostatic part of physics, an early econophysical approach for global financial crises was studied. The aim is to define a model that can take place before the financial crises, identify financial fragility at an earlier stage and help public and private sector members, policy makers and economists with an econophysical approach. 2001 Turkey crisis has been assessed with data from Turkish Central Bank which is covered between 1992 to 2007, and for 2001 Argentina crisis, data was taken from IMF and the Central Bank of Argentina from 1997 to 2007. As an econophysical method, an analogy is used between the Gauss's law used in the calculation of the electric field and the forecasting of the financial crisis. The concept of Φ (Financial Flux) has been adopted for the pre-warning of the crisis by taking advantage of this analogy, which is based on currency movements and money mobility. For the first time used in this study Φ (Financial Flux) calculations obtained by the formula were analyzed by Matlab software, and in this context, in 2001 Turkey and Argentina Crisis for Φ (Financial Flux) crisis of values has been confirmed to give pre-warning.Keywords: econophysics, financial crisis, Gauss's Law, physics
Procedia PDF Downloads 153775 Analysis and Modeling of Stresses and Creeps Resulting from Soil Mechanics in Southern Plains of Kerman Province
Authors: Kourosh Nazarian
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Many of the engineering materials, such as behavioral metals, have at least a certain level of linear behavior. It means that if the stresses are doubled, the deformations would be also doubled. In fact, these materials have linear elastic properties. Soils do not follow this law, for example, when compressed, soils become gradually tighter. On the surface of the ground, the sand can be easily deformed with a finger, but in high compressive stresses, they gain considerable hardness and strength. This is mainly due to the increase in the forces among the separate particles. Creeps also deform the soils under a constant load over time. Clay and peat soils have creep behavior. As a result of this phenomenon, structures constructed on such soils will continue their collapse over time. In this paper, the researchers analyzed and modeled the stresses and creeps in the southern plains of Kerman province in Iran through library-documentary, quantitative and software techniques, and field survey. The results of the modeling showed that these plains experienced severe stresses and had a collapse of about 26 cm in the last 15 years and also creep evidence was discovered in an area with a gradient of 3-6 degrees.Keywords: Stress, creep, faryab, surface runoff
Procedia PDF Downloads 179774 Integrating Individual and Structural Health Risk: A Social Identity Perspective on the HIV/AIDS Pandemic in Sub-Saharan Africa
Authors: Orla Muldoon, Tamaryn Nicolson, Mike Quayle, Aisling O'Donnell
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Psychology most often considers the role of experience and behaviour in shaping health at the individual level. On the other hand epidemiology has long considered risk at the wider group or structural level. Here we use the social identity approach to integrate group-level risk with individual level behaviour. Using a social identity approach we demonstrate that group or macro-level factors impact implicitly and profoundly in everyday ways at the level of individuals, via social identities. We illustrate how identities related to race, gender and inequality intersect to affect HIV/AIDS risk and AIDS treatment behaviours; how social identity processes drive stigmatising consequences of HIV and AIDS, and promote positive and effective interventions. We conclude by arguing that the social identity approach offers the field an explanatory framework that conceptualizes how social and political forces intersect with individual identity and agency to affect human health.Keywords: social identity approach, HIV/AIDS, Africa, HIV risk, race, gender
Procedia PDF Downloads 529773 Integrating the Athena Vortex Lattice Code into a Multivariate Design Synthesis Optimisation Platform in JAVA
Authors: Paul Okonkwo, Howard Smith
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This paper describes a methodology to integrate the Athena Vortex Lattice Aerodynamic Software for automated operation in a multivariate optimisation of the Blended Wing Body Aircraft. The Athena Vortex Lattice code developed at the Massachusetts Institute of Technology by Mark Drela allows for the aerodynamic analysis of aircraft using the vortex lattice method. Ordinarily, the Athena Vortex Lattice operation requires a text file containing the aircraft geometry to be loaded into the AVL solver in order to determine the aerodynamic forces and moments. However, automated operation will be required to enable integration into a multidisciplinary optimisation framework. Automated AVL operation within the JAVA design environment will nonetheless require a modification and recompilation of AVL source code into an executable file capable of running on windows and other platforms without the –X11 libraries. This paper describes the procedure for the integrating the FORTRAN written AVL software for automated operation within the multivariate design synthesis optimisation framework for the conceptual design of the BWB aircraft.Keywords: aerodynamics, automation, optimisation, AVL, JNI
Procedia PDF Downloads 582772 Effect of Microstructure of Graphene Oxide Fabricated through Different Self-Assembly Techniques on Alcohol Dehydration
Authors: Wei-Song Hung
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We utilized pressure, vacuum, and evaporation-assisted self-assembly techniques through which graphene oxide (GO) was deposited on modified polyacrylonitrile (mPAN). The fabricated composite GO/mPAN membranes were applied to dehydrate 1-butanol mixtures by pervaporation. Varying driving forces in the self-assembly techniques induced different GO assembly layer microstructures. XRD results indicated that the GO layer d-spacing varied from 8.3 Å to 11.5 Å. The self-assembly technique with evaporation resulted in a heterogeneous GO layer with loop structures; this layer was shown to be hydrophobic, in contrast to the hydrophilic layer formed from the other two techniques. From the pressure-assisted technique, the composite membrane exhibited exceptional pervaporation performance at 30 C: concentration of water at the permeate side = 99.6 wt% and permeation flux = 2.54 kg m-2 h-1. Moreover, the membrane sustained its operating stability at a high temperature of 70 C: a high water concentration of 99.5 wt% was maintained, and a permeation flux as high as 4.34 kg m-2 h-1 was attained. This excellent separation performance stemmed from the dense, highly ordered laminate structure of GO.Keywords: graphene oxide, self-assembly, alcohol dehydration, polyacrylonitrile (mPAN)
Procedia PDF Downloads 295771 Domains of Socialization Interview: Development and Psychometric Properties
Authors: Dilek Saritas Atalar, Cansu Alsancak Akbulut, İrem Metin Orta, Feyza Yön, Zeynep Yenen, Joan Grusec
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Objective: The aim of this study was to develop semi-structured Domains of Socialization Interview and its coding manual and to test their psychometric properties. Domains of Socialization Interview was designed to assess maternal awareness regarding effective parenting in five socialization domains (protection, mutual reciprocity, control, guided learning, and group participation) within the framework of the domains-of-socialization approach. Method: A series of two studies were conducted to develop and validate the interview and its coding manual. The pilot study, sampled 13 mothers of preschool-aged children, was conducted to develop the assessment tools and to test their function and clarity. Participants of the main study were 82 Turkish mothers (Xage = 34.25, SD = 3.53) who have children aged between 35-76 months (Xage = 50.75, SD = 11.24). Mothers filled in a questionnaire package including Coping with Children’s Negative Emotions Questionnaire, Social Competence and Behavior Evaluation-30, Child Rearing Questionnaire, and Two Dimensional Social Desirability Questionnaire. Afterward, interviews were conducted online by a single interviewer. Interviews were rated independently by two graduate students based on the coding manual. Results: The relationships of the awareness of effective parenting scores to the other measures demonstrate convergent, discriminant, and predictive validity of the coding manual. Intra-class correlation coefficient estimates were ranged between 0.82 and 0.90, showing high interrater reliability of the coding manual. Conclusion: Taken as a whole, the results of these studies demonstrate the validity and reliability of a new and useful interview to measure maternal awareness regarding effective parenting within the framework of the domains-of-socialization approach.Keywords: domains of socialization, parenting, interview, assessment
Procedia PDF Downloads 189770 Effects of X and + Tail-Body Configurations on Hydrodynamic Performance and Stability of an Underwater Vehicle
Authors: Kadri Koçer, Sezer Kefeli
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This paper proposes a comparison of hydrodynamic performance and stability characteristic for an underwater vehicle which has two type of tail design, namely X and +tail-body configurations. The effects of these configurations on the underwater vehicle’s hydrodynamic performance and maneuvering characteristic will be investigated comprehensively. Hydrodynamic damping coefficients for modeling the motion of the underwater vehicles will be predicted. Additionally, forces and moments due to control surfaces will be compared using computational fluid dynamics methods. In the aviation, the X tail-body configuration is widely used for high maneuverability requirements. However, in the underwater, the + tail-body configuration is more commonly used than the X tail-body configuration for its stability characteristics. Thus it is important to see the effect and differences of the tail designs in the underwater world. For CFD analysis, the incompressible, three-dimensional, and steady Navier-Stokes equations will be used to simulate the flows. Also, k-ε Realizable turbulence model with enhanced wall treatment will be taken. Numerical results is verified with experimental results for verification. The overall goal of this study is to present the advantages and disadvantages of hydrodynamic performance and stability characteristic for X and + tail-body configurations of the underwater vehicle.Keywords: maneuverability, stability, CFD, tail configuration, hydrodynamic design
Procedia PDF Downloads 184769 Market Acceptance of a Murabaha-Based Finance Structure within a Social Network of Non-Islamic Small and Medium Enterprise Owners in African Procurement
Authors: Craig M. Allen
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Twenty two African entrepreneurs with Small and Medium Enterprises (SMEs) in a single social network centered around a non-Muslim population in a smaller African country, selected an Islamic financing structure, a form of Murabaha, based solely on market rationale. These entrepreneurs had all won procurement contracts from major purchasers of goods within their country and faced difficulty arranging traditional bank financing to support their supply-chain needs. The Murabaha-based structure satisfied their market-driven demand and provided an attractive alternative to the traditional bank-offered lending products. The Murabaha-styled trade-financing structure was not promoted with any religious implications, but solely as a market solution to the existing problems associated with bank-related financing. This indicates the strong market forces that draw SMEs to financing structures that are traditionally considered within the framework of Islamic finance.Keywords: Africa, entrepreneurs, Islamic finance, market acceptance, Murabaha, SMEs
Procedia PDF Downloads 181768 Adherence Induced Formwork Removal in Small-Scale Pull-Off Tensile Tests
Authors: Nicolas Spitz, Nicolas Coniglio, Mohamed El Mansori, Alex Montagne, Sabeur Mezghani
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Nowadays buildings' construction is performed by pouring concrete into molds referred to as formworks that are usually prefabricated metallic modules. Defects such as stripping may possibly form during the removal of the formwork if the interfacial bonding between the concrete and the formwork is high. A new pull-off tensile test was developed in our laboratory to simulate small-scale formwork removals. The concrete-to-formwork adherence force was measured on bare and coated formworks with different surface signatures. The used concrete was a mixture largely used on building sites and contains CEM I Portland cement and calcareous filler. The concrete surface appearance and the type of failures at the concrete-formwork interface have been investigated. The originality of this near-to-surface test was to compare the laboratory-measured adherence forces to the on-site observations. Based upon the small-scale laboratory test results, functional formwork specifications with low adherence to concrete was proposed in terms of superficial signature characteristics.Keywords: concrete-formwork adherence, interfacial bonding, skin formwork functionality, small-scale pull-off tensile test
Procedia PDF Downloads 246767 On the Evaluation of Critical Lateral-Torsional Buckling Loads of Monosymmetric Beam-Columns
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Beam-column elements are defined as structural members subjected to a combination of axial and bending forces. Lateral torsional buckling is one of the major failure modes in which beam-columns that are bent about its strong axis may buckle out of the plane by deflecting laterally and twisting. This study presents a compact closed-form equation that it can be used for calculating critical lateral torsional-buckling load of beam-columns with monosymmetric sections in the presence of a known axial load. Lateral-torsional buckling behavior of beam-columns subjected to constant axial force and various transverse load cases are investigated by using Ritz method in order to establish proposed equation. Lateral-torsional buckling loads calculated by presented formula are compared to finite element model results. ABAQUS software is utilized to generate finite element models of beam-columns. It is found out that lateral-torsional buckling load of beam-columns with monosymmetric sections can be determined by proposed equation and can be safely used in design.Keywords: lateral-torsional buckling, stability, beam-column, monosymmetric section
Procedia PDF Downloads 324766 A Nuclear Negotiation Qualitative Case Study with Force Field Analysis
Authors: Onur Yuksel
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In today’s complex foreign relations between countries, the nuclear enrichment and nuclear weapon have become a threat for all states in the world. There are couple isolated states which have capacity to produce nuclear weapons such as Iran and North Korea. In this article, Iran nuclear negotiation was analyzed in terms of its relations especially with The United States in order to find the important factors that affect the course of the ongoing nuclear negotiation. In this sense, the Force Field Analysis was used by determining and setting forth Driving and Restraining Forces of the nuclear negotiations in order to see the big picture and to develop strategies that may improve the long-term ongoing Iran nuclear negotiations. It is found that Iran nuclear negotiation heavily depends on breaking down the idea of Iran’s supporting terrorist organizations and being more transparent about nuclear and uranium enrichment. Also, it was found that Iran has to rebuild its relations with Western countries, especially with the United States. In addition, the counties— who contribute to Iran nuclear negotiations— will need to work on the dynamics and drivers of the Israel and Iran relations in order to peacefully transform the conflict between the two states.Keywords: driving force, Iran nuclear negotiation, restraining force, the force field analysis
Procedia PDF Downloads 158765 Private Decisions, Public Results: German Business Action in Response to the Refugee Crisis
Authors: O. M. van den Broek
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This article examines how large German companies have responded to the 2014 refugee crisis. It challenges the assumption that the historical legacy of implicit CSR in Germany would lead to low levels of business response through CSR channels. Instead, and building on institutional CSR and the converging forces of globalization, this article argues that the urgency of a humanitarian crisis creates incentives, in the absence of formal institutional arrangement, for explicit CSR responses. This explorative research encompasses the 53 German companies presented on 2015 Forbes2000. A qualitative content analysis of corporate websites was supplemented with inquiry e-mails. Results indicate considerable evidence for the main hypothesis, showing a vast majority of companies responding to the refugee crisis. Levels of engagement varied, depending on the phase of the crisis, from core-business activities to non-integrated action. The high level of partnerships with the state and other non-state actors indicates a quest for enhanced legitimacy in the face of an absent democratic mandate.Keywords: corporate social responsibility (CSR), implicit versus explicit CSR, public-private partnerships, European refugee crisis
Procedia PDF Downloads 167764 Complex Dynamics in a Morphologically Heterogeneous Biological Medium
Authors: Turky Al-Qahtani, Roustem Miftahof
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Introduction: Under common assumptions of excitabi-lity, morphological (cellular) homogeneity, and spatial structural anomalies added as required, it has been shown that biological systems are able to display travelling wave dynamics. Being not self-sustainable, existence depends on the electrophysiological state of transmembrane ion channels and it requires an extrinsic/intrinsic periodic source. However, organs in the body are highly multicellular, heterogeneous, and their functionality is the outcome of electro-mechanical conjugation, rather than excitability only. Thus, peristalsis in the gut relies on spatiotemporal myoelectrical pattern formations between the mechanical, represented by smooth muscle cells (SM), and the control, comprised of a chain of primary sensory and motor neurones, components. Synaptically linked through the afferent and efferent pathways, they form a functional unit (FU) of the gut. Aims: These are: i) to study numerically the complex dynamics, and ii) to investigate the possibility of self-sustained myoelectrical activity in the FU. Methods: The FU recreates the following sequence of physiological events: deformation of mechanoreceptors of located in SM; generation and propagation of electrical waves of depolarisation - spikes - along the axon to the soma of the primary neurone; discharge of the primary neurone and spike propagation towards the motor neurone; burst of the motor neurone and transduction of spikes to SM, subsequently producing forces of contraction. These are governed by a system of nonlinear partial and ordinary differential equations being a modified version of the Hodgkin-Huxley model and SM fibre mechanics. In numerical experiments; the source of excitation is mechanical stretches of SM at a fixed amplitude and variable frequencies. Results: Low frequency (0.5 < v < 2 Hz) stimuli cause the propagation of spikes in the neuronal chain and, finally, the generation of active forces by SM. However, induced contractions are not sufficient to initiate travelling wave dynamics in the control system. At frequencies, 2 < v < 4 Hz, multiple low amplitude and short-lasting contractions are observed in SM after the termination of stretching. For frequencies (0.5 < v < 4 Hz), primary and sensory neurones demonstrate strong connectivity and coherent electrical activity. Significant qualitative and quantitative changes in dynamics of myoelectical patterns with a transition to a self-organised mode are recorded with the high degree of stretches at v = 4.5 Hz. Increased rates of deformation lead to the production of high amplitude signals at the mechanoreceptors with subsequent self-sustained excitation within the neuronal chain. Remarkably, the connection between neurones weakens resulting in incoherent firing. Further increase in a frequency of stimulation (v > 4.5 Hz) has a detrimental effect on the system. The mechanical and control systems become disconnected and exhibit uncoordinated electromechanical activity. Conclusion: To our knowledge, the existence of periodic activity in a multicellular, functionally heterogeneous biological system with mechano-electrical dynamics, such as the FU, has been demonstrated for the first time. These findings support the notion of possible peristalsis in the gut even in the absence of intrinsic sources - pacemaker cells. Results could be implicated in the pathogenesis of intestinal dysrythmia, a medical condition associated with motor dysfunction.Keywords: complex dynamics, functional unit, the gut, dysrythmia
Procedia PDF Downloads 204763 Determination of Stresses in Vlasov Beam Sections
Authors: Semih Erdogan
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In this paper, the normal and shear stress distributions in Vlasov beams are determined by two-dimensional triangular finite element formulations. The proposed formulations take into account the warping effects along the beam axis. The shape of the considered beam sections may be arbitrary and varied throughout its length. The stiffness matrices and force vectors are derived for transversal forces, uniform torsion, and nonuniform torsion. The proposed finite element algorithm is validated by comparing the analytical solutions, structural engineering books, and related articles. The numerical examples include beams with different cross-section types such as solid, thick-walled, closed-thin-walled, and open-thin-walled sections. Materials defined in the examples are homogeneous, isotropic, and linearly elastic. Through these examples, the study demonstrates the capability of the proposed method to address a wide range of practical engineering scenarios.Keywords: Vlasov beams, warping function, nonuniform torsion, finite element method, normal and shear stresses, cross-section properties
Procedia PDF Downloads 64762 Simulation of the Asphaltene Deposition Rate in a Wellbore Blockage via Computational Fluid Dynamic
Authors: Xiaodong Gao, Pingchuan Dong, Qichao Gao
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There has been lots of published work focused on asphaltene deposited on the smooth pipe under steady conditions, while particle deposition on the blockage wellbores under transient conditions has not been well elucidated. This work attempts to predict the deposition rate of asphaltene particles in blockage tube through CFD simulation. The Euler-Lagrange equation has been applied during the flow of crude oil and asphaltene particles. The net gravitational force, virtual mass, pressure gradient, saffman lift, and drag forces are incorporated in the simulations process. Validation of CFD simulation results is compared to the benchmark experiments from the previous literature. Furthermore, the effect of blockage location, blockage length, and blockage thickness on deposition rate are also analyzed. The simulation results indicate that the maximum deposition rate of asphaltene occurs in the blocked tube section, and the greater the deposition thickness, the greater the deposition rate. Moreover, the deposition amount and maximum deposition rate along the length of the tube have the same trend. Results of this study are in the ability to better understand the deposition of asphaltene particles in production and help achieve to deal with the asphaltene challenges.Keywords: asphaltene deposition rate, blockage length, blockage thickness, blockage diameter, transient condition
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