Search results for: intelligent memory structures

Authors: Xiao Zhou, Jianlin Cheng

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A single amino acid mutation can have a significant impact on the stability of protein structure. Thus, the prediction of protein stability change induced by single site mutations is critical and useful for studying protein function and structure. Here, we presented a deep learning network with the dropout technique for predicting protein stability changes upon single amino acid substitution. While using only protein sequence as input, the overall prediction accuracy of the method on a standard benchmark is >85%, which is higher than existing sequence-based methods and is comparable to the methods that use not only protein sequence but also tertiary structure, pH value and temperature. The results demonstrate that deep learning is a promising technique for protein stability prediction. The good performance of this sequence-based method makes it a valuable tool for predicting the impact of mutations on most proteins whose experimental structures are not available. Both the downloadable software package and the user-friendly web server (DNpro) that implement the method for predicting protein stability changes induced by amino acid mutations are freely available for the community to use.

Keywords: bioinformatics, deep learning, protein stability prediction, biological data mining

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Authors: Gabriela Teodorescu, Ioana Daniela Dulama

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In an ever-changing society, the education system needs to constantly evolve to meet market demands. During its 30 years of existence, Valahia University of Targoviste (VUT) tried to offer its students a series of teaching-learning schemes that would prepare them for a remarkable career. In VUT, the achievement of performance through innovation can be analyzed by reference to several key indicators (i.e., university climate, university resources, and innovative methods applied to classes), but it is possible to differentiate between activities in the classic format: participate to courses; interactive seminars and tutorials; laboratories, workshops, project-based learning; entrepreneurial activities, through simulated enterprises; mentoring activities. Thus, VUT has implemented over time a series of schemes and projects based on innovation and entrepreneurship, and in this paper, some of them will be briefly presented. All these schemes were implemented by facilitating an effective dialog with students and the opportunity to listen to their views at all levels of the University and in all fields of study, as well as by developing a partnership with students to set out priority areas. VUT demonstrates innovation and entrepreneurial capacity through its new activities for higher education, which will attract more partnerships and projects dedicated to students.

Keywords: Romania, project-based learning, entrepreneurial activities, simulated enterprises

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Authors: Sreekanth T. G., Kishorekumar S., Sowndhariya Kumar J., Karthick R., Shanmugasuriyan S.

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Composites are increasingly being used in industries due to their unique properties, such as high specific stiffness and specific strength, higher fatigue and wear resistances, and higher damage tolerance capability. Composites are prone to failures or damages that are difficult to identify, locate, and characterize due to their complex design features and complicated loading conditions. The lack of understanding of the damage mechanism of the composites leads to the uncertainties in the structural integrity and durability. Delamination is one of the most critical failure mechanisms in laminated composites because it progressively affects the mechanical performance of fiber-reinforced polymer composite structures over time. The identification and severity characterization of delamination in engineering fields such as the aviation industry is critical for both safety and economic concerns. The presence of delamination alters the vibration properties of composites, such as natural frequencies, mode shapes, and so on. In this study, numerical analysis and experimental analysis were performed on delaminated and non-delaminated glass fiber reinforced polymer (GFRP) plate, and the numerical and experimental analysis results were compared, and error percentage has been found out.

Keywords: composites, delamination, natural frequency, mode shapes

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Authors: Harvinder Kaur

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Rayleigh–Ritz method is a broadly used classical method for the calculation of the natural vibration frequency of a structure in the second or higher order. Here it is used to construct a mathematical model of relative study of the thermal effect on free transverse vibrations of clamped (c-c-c-c type) visco-elastic rectangular plate with linearly and exponentially thickness variations respectively in two directions. Researchers in the field of Engineering always make an effort for better designs of mechanical structures. In-depth study of the vibration behavior of tapered plates with diverse thickness variation under high temperature would ultimately help to finalize the accurate design of a structure. The perfect tapered structure saves weight and as well as expenses. In the present paper, the comparison has been done for deflection and time period corresponding to the first two modes of vibrations of clamped plate for various values of aspect ratio, thermal constants, and taper constants of both the cases.

Keywords: Rayleigh-Ritz Method, tapered plates, transverse vibration, thermal constant, visco-elasticity

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Authors: Memory Ranga, Phillip Pretorious

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The South African Government has invested a lot of money in Information Technology Governance (ITG) within the Government departments. The ITG framework was spearheaded by the Department of Public Service and Administration (DPSA). This led to the development of a governing ITG DPSA framework and later the Government Wide Enterprise Architecture (GWEA) Framework for assisting the departments to implement ITG. In addition to this, the government departments have adopted the Information Systems Audit and Control Association (ISACA) Control Objectives for Information and Related Technology (COBIT) for ITG processes. Despite all these available frameworks, departments fail to fully capitalise and improve the ITG processes mainly as these are too generic and difficult to apply for specific governance needs. There has been less research done to evaluate the progress on ITG initiatives within the government departments. This paper aims to evaluate the existing ITG frameworks within selected government departments in South Africa. A quantitative research approach was used in this study. Data was collected through an online questionnaire targeting ICT Managers and Directors from government departments. The study is undertaken within a case study and only the Eastern Cape Province was selected for the research. Document review mainly on ITG framework and best practices was also used. Data was analysed using the Google Analytic tools and SPSS. A one–sample Chi-Squared Test was used to verity the evaluation findings. Findings show that there is evidence that the current guiding National governance framework (DPSA) is out dated and does not accommodate the new changes in other governance frameworks. The Eastern Cape Government Departments have spent huge amount of money on ITG but not yet able to identify the benefits of the ITG initiatives. The guiding framework is rigid and does to address some of the departmental needs making it difficult to be flexible and apply the DPSA framework. Furthermore, despite the large budget on ITG, the departments still find themselves with many challenges and unable to improve some of the processes and services. All the engaged Eastern Cape departments have adopted the COBIT framework, but none has been conducting COBIT maturity Assessment which is a functionality of COBIT. There is evidence of too many the ITG frameworks and underutilisation of these frameworks. The study provides a comprehensive evaluation of the ITG frameworks that have been adopted by the South African Government Departments in the Eastern Cape Province. The evaluation guides and recommends the government departments to rethink and adopt ITG frameworks that could be customised to accommodate their needs. The adoption and application of ITG by government departments should assist in better governance and service delivery to the citizens.

Keywords: information technology governance, COBIT, evaluate, framework, governance, DPSA framework

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Authors: Wenxue Xu

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Fluid resistance damper is an important damping element to attenuate vehicle vibration. It converts vibration energy into thermal energy dissipation through oil throttling. It is a typical fluid-solid-heat coupling problem. A complete three-dimensional flow-structure-thermal coupling dynamics simulation model of a gas-filled fluid-resistance damper was established. The flow-condition-based interpolation (FCBI) method and direct coupling calculation method, the unit's FCBI-C fluid numerical analysis method and iterative coupling calculation method are used to achieve the damper dynamic response of the piston rod under sinusoidal excitation; the air chamber inflation pressure, spring compression characteristics, constant flow passage cross-sectional area and oil parameters, etc. The system parameters, excitation frequency, and amplitude and other excitation parameters are analyzed and compared in detail for the effects of differential pressure characteristics, velocity characteristics, flow characteristics and dynamic response of valve opening, floating piston response and piston rod output force characteristics. Experiments were carried out on some simulation analysis conditions. The results show that the node-based FCBI (flow-condition-based interpolation) fluid numerical analysis method and direct coupling calculation method can better guarantee the conservation of flow field calculation, and the calculation step is larger, but the memory is also larger; if the chamber inflation pressure is too low, the damper will become cavitation. The inflation pressure will cause the speed characteristic hysteresis to increase, and the sealing requirements are too strict. The spring compression characteristics have a great influence on the damping characteristics of the damper, and reasonable damping characteristic needs to properly design the spring compression characteristics; the larger the cross-sectional area of the constant flow channel, the smaller the maximum output force, but the more stable when the valve plate is opening.

Keywords: damper, fluid-structure-thermal coupling, heat generation, heat transfer

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Authors: Sylvain Caillol, Ghislain David

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Phenolic resins are industrially used in a wide range of applications from commodity and construction materials to high-technology aerospace industry. They are mainly produced from the reaction between phenolic compounds and formaldehyde. Nevertheless, formaldehyde is a highly volatile and hazardous compound, classified as a Carcinogenic, Mutagenic and Reprotoxic chemical (CMR). Vanillin is a bio-based and non-toxic aromatic aldehyde compound obtained from the abundant lignin resources. Also, its aromaticity is very interesting for the synthesis of phenolic resins with high thermal stability. However, because of the relatively low reactivity of its aldehyde function toward phenolic compounds, it has never been used to synthesize phenolic resins. We developed innovative functionalization reactions and designed new bio-based aromatic aldehyde compounds from vanillin. Those innovative compounds present improved reactivity toward phenolic compounds compared to vanillin. Moreover, they have target structures to synthesize highly cross-linked phenolic resins with high aromatic densities. We have obtained phenolic resins from substituted vanillin, thus without the use of any aldehyde compound classified as CMR. The analytical tests of the cured resins confirmed that those bio-based resins exhibit high levels of performance with high thermal stability and high rigidity properties

Keywords: phenolic resins, formaldehyde-free, vanillin, bio-based, non-toxic

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Authors: Martin Cvek, Miroslav Mrlik, Michal Sedlacik, Tomas Plachy

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Magnetorheological elastomers (MREs) are multi-phase composite materials containing micron-sized ferromagnetic particles dispersed in an elastomeric matrix. Their properties such as modulus, damping, magneto-striction, and electrical conductivity can be controlled by an external magnetic field and/or pressure. These features of the MREs are used in the development of damping devices, shock attenuators, artificial muscles, sensors or active elements of electric circuits. However, imperfections on the particle/matrix interfaces result in the lower performance of the MREs when compared with theoretical values. Moreover, magnetic particles are susceptible to corrosion agents such as acid rains or sea humidity. Therefore, the modification of particles is an effective tool for the improvement of MRE performance due to enhanced compatibility between particles and matrix as well as improvements of their thermo-oxidation and chemical stability. In this study, the carbonyl iron (CI) particles were controllably modified with poly(trimethylsilyloxyethyl methacrylate) (PHEMATMS) nano-grafts to develop magnetic core–shell structures exhibiting proper wetting with various elastomeric matrices resulting in improved performance within a frame of rheological, magneto-piezoresistance, pressure-piezoresistance, or radio-absorbing properties. The desired molecular weight of PHEMATMS nano-grafts was precisely tailored using surface-initiated atom transfer radical polymerization (ATRP). The CI particles were firstly functionalized using a 3-aminopropyltriethoxysilane agent, followed by esterification reaction with α-bromoisobutyryl bromide. The ATRP was performed in the anisole medium using ethyl α-bromoisobutyrate as a macroinitiator, N, N´, N´´, N´´-pentamethyldiethylenetriamine as a ligand, and copper bromide as an initiator. To explore the effect PHEMATMS molecular weights on final properties, two variants of core-shell structures with different nano-graft lengths were synthesized, while the reaction kinetics were designed through proper reactant feed ratios and polymerization times. The PHEMATMS nano-grafts were characterized by nuclear magnetic resonance and gel permeation chromatography proving information to their monomer conversions, molecular chain lengths, and low polydispersity indexes (1.28 and 1.35) as the results of the executed ATRP. The successful modifications were confirmed via Fourier transform infrared- and energy-dispersive spectroscopies while expected wavenumber outputs and element presences, respectively, of constituted PHEMATMS nano-grafts, were occurring in the spectra. The surface morphology of bare CI and their PHEMATMS-grafted analogues was further studied by scanning electron microscopy, and the thicknesses of grafted polymeric layers were directly observed by transmission electron microscopy. The contact angles as a measure of particle/matrix compatibility were investigated employing the static sessile drop method. The PHEMATMS nano-grafts enhanced compatibility of hydrophilic CI with low-surface-energy hydrophobic polymer matrix in terms of their wettability and dispersibility in an elastomeric matrix. Thus, the presence of possible defects at the particle/matrix interface is reduced, and higher performance of modified MREs is expected.

Keywords: atom transfer radical polymerization, core-shell, particle modification, wettability

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Authors: K. Benyounes, A. Benmounah

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Cement-based grouts has been used successfully to repair cracks in many concrete structures such as bridges, tunnels, buildings and to consolidate soils or rock foundations. In the present study, the rheological characterization of cement grout with water/binder ratio (W/B) is fixed at 0.5. The effect of the replacement of cement by bentonite (2 to 10 % wt) in presence of superplasticizer (0.5 % wt) was investigated. Several rheological tests were carried out by using controlled-stress rheometer equipped with vane geometry in temperature of 20°C. To highlight the influence of bentonite and superplasticizer on the rheological behavior of grout cement, various flow tests in a range of shear rate from 0 to 200 s-1 were observed. Cement grout showed a non-Newtonian viscosity behavior at all concentrations of bentonite. Three parameter model Herschel-Bulkley was chosen for fitting of experimental data. Based on the values of correlation coefficients of the estimated parameters, The Herschel-Bulkley law model well described the rheological behavior of the grouts. Test results showed that the dosage of bentonite increases the viscosity and yield stress of the system and introduces more thixotropy. While the addition of both bentonite and superplasticizer with cement grout improve significantly the fluidity and reduced the yield stress due to the action of dispersion of SP.

Keywords: rheology, cement grout, bentonite, superplasticizer, viscosity, yield stress

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Authors: H. Ozbasaran

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IPN and IPE sections, which are commonly used European I shapes, are widely used in steel structures as cantilever beams to support overhangs. A considerable number of studies exist on calculating lateral torsional buckling load of I sections. However, most of them provide series solutions or complex closed-form equations. In this paper, a simple equation is presented to calculate lateral torsional buckling load of IPN and IPE section cantilever beams. First, differential equation of lateral torsional buckling is solved numerically for various loading cases. Then a parametric study is conducted on results to present an equation for lateral torsional buckling load of European IPN and IPE beams. Finally, results obtained by presented equation are compared to differential equation solutions and finite element model results. ABAQUS software is utilized to generate finite element models of beams. It is seen that the results obtained from presented equation coincide with differential equation solutions and ABAQUS software results. It can be suggested that presented formula can be safely used to calculate critical lateral torsional buckling load of European IPN and IPE section cantilevers.

Keywords: cantilever, IPN, IPE, lateral torsional buckling

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Authors: Tugrul Tulunay, Iyas Devran Celik

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When the materials used in structural steel industry are evaluated, box beam profiles are considerably preferred. As a result of the cross-sectional properties that these profiles possess, the connection of these profiles to each other and to profiles having different types of cross sections is becoming viable by means of additional measures. An important point to note in such combinations is continuous transfer of internal forces from element to element. At the beginning to ensure this continuity, header plate is needed to use. The connection of the plates to the elements works mainly through welds. In this study, it is aimed to determine the ideal welding thickness in box beam under bending effect and the joints exposed to local buckles that will form in the column. The connection with box column and box beam designed in this context was made by means of corner and circular filler welds. Corner welds of different thickness and analysis by types with different lengths depending on plate dimensions in numerical models were made with the help of ANSYS Workbench program and examined behaviours.

Keywords: welding thickness, box beam-column joints, design of steel structures, calculation and construction principles 2016, welded joints under local buckling

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Authors: Weinian Wang, Joseph C. Chen

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The objective of this research is to optimize the process of cutting cylindrical workpieces utilizing live tooling on a HAAS ST-20 lathe. Surface roughness (Ra) has been investigated as the indicator of quality characteristics for machining process. Aluminum alloy was used to conduct experiments due to its wide range usages in engineering structures and components where light weight or corrosion resistance is required. In this study, Taguchi methodology is utilized to determine the effects that each of the parameters has on surface roughness (Ra). A total of 18 experiments of each process were designed according to Taguchi’s L9 orthogonal array (OA) with four control factors at three levels of each and signal-to-noise ratios (S/N) were computed with Smaller the better equation for minimizing the system. The optimal parameters identified for the surface roughness of the turning operation utilizing live tooling were a feed rate of 3 inches/min(A3); a spindle speed of 1300 rpm(B3); a 2-flute titanium nitrite coated 3/8” endmill (C1); and a depth of cut of 0.025 inches (D2). The mean surface roughness of the confirmation runs in turning operation was 8.22 micro inches. The final results demonstrate that Taguchi methodology is a sufficient way of process improvement in turning process on surface roughness.

Keywords: CNC milling operation, CNC turning operation, surface roughness, Taguchi parameter design

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Authors: Fatai Shola Afolabi

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The study identified and evaluates the causes of building failure and examined the effects of building failure with respect to cost in Lagos State, Nigeria. The method employed in the collection of data includes the administration of questionnaire to professionals in the construction industry and case studies for the sites. A purposive sampling technique was used for selecting the sites visited, and selecting the construction professionals. Descriptive statistical techniques such as frequency distribution and percentages and mean response analysis were used to analyze data. The study revealed that the major causes of building failures were bad design, faulty construction, over loading, non-possession of approved drawings, Possession of approved drawings but non-compliance, and the use of quarks. In the two case studies considered, the total direct loss to the building owners was thirty eight million three hundred and eight five thousand, seven hundred and twenty one naira (38,385,721) which is about One hundred and ninety four thousand, eighty hundred and fifty one dollars ($194,851) at one hundred and ninety seven naira to one US dollars, central bank Nigeria of exchange rate as at 14th March, 2015.

Keywords: building structures, building failure, building collapse, structural failure, cost, direct loss

Procedia PDF Downloads 263

Authors: Haowen Xu, Xiaobing Liu, Jin Dong, Jianming Lian

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Emerging smart buildings often employ cyberinfrastructure, cyber-physical systems, and Internet of Things (IoT) technologies to increase the automation and responsiveness of building operations for better energy efficiency and lower carbon emission. These operations include the control of Heating, Ventilation, and Air Conditioning (HVAC) and lighting systems, which are often considered a major source of energy consumption in both commercial and residential buildings. Developing energy-saving control models for optimizing HVAC operations usually requires the collection of high-quality instrumental data from iterations of in-situ building experiments, which can be time-consuming and labor-intensive. This abstract describes a digital twin approach to automate building energy experiments for optimizing HVAC operations through the design and development of an adaptive web-based platform. The platform is created to enable (a) automated data acquisition from a variety of IoT-connected HVAC instruments, (b) real-time situational awareness through domain-based visualizations, (c) adaption of HVAC optimization algorithms based on experimental data, (d) sharing of experimental data and model predictive controls through web services, and (e) cyber-physical control of individual instruments in the HVAC system using outputs from different optimization algorithms. Through the digital twin approach, we aim to replicate a real-world building and its HVAC systems in an online computing environment to automate the development of building-specific model predictive controls and collaborative experiments in buildings located in different climate zones in the United States. We present two case studies to demonstrate our platform’s capability for real-time situational awareness and cyber-physical control of the HVAC in the flexible research platforms within the Oak Ridge National Laboratory (ORNL) main campus. Our platform is developed using adaptive and flexible architecture design, rendering the platform generalizable and extendable to support HVAC optimization experiments in different types of buildings across the nation.

Keywords: energy-saving buildings, digital twins, HVAC, cyber-physical system, BIM

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Authors: Merav Alush Levron, Sivan Rajuan Shtang

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From as early as their emergence in Europe and the US, postmodern and post-colonial paradigm have formed the backbone of the visual culture field of study. The self-representation project of political minorities is studied, described and explained within the premises and perspectives drawn from these paradigms, addressing the key issues they had raised: modernism’s crisis of representation. The struggle for self-representation, agency and multicultural visibility sought to challenge the liberal pretense of universality and equality, hitting at its different blind spots, on issues such as class, gender, race, sex, and nationality. This struggle yielded subversive identity and hybrid performances, including reclaiming, mimicry and masquerading. These performances sought to defy the uniform, universal self, which forms the basis for the liberal, rational, enlightened subject. The argument of this research runs that this politics of representation itself is confined within liberal thought. Alongside post-colonialism and multiculturalism’s contribution in undermining oppressive structures of power, generating diversity in cultural visibility, and exposing the failure of liberal colorblindness, this subversion is constituted in the visual field by way of confrontation, flying in the face of the universal law and relying on its ongoing comparison and attribution to this law. Relying on Deleuze and Guattari, this research set out to draw theoretic and empiric attention to an alternative, post-liberal occurrence which has been taking place in the visual field in parallel to the contra-hegemonic phase and as a product of political reality in the aftermath of the crisis of representation. It is no longer a counter-representation; rather, it is a motion of organic minor desire, progressing in the form of flows and generating what Deleuze and Guattari termed deterritorialization of social structures. This discussion shall have its focus on current post-liberal performances of ‘Mizrahim’ (Jewish Israelis of Arab and Muslim extraction) in the visual field in Israel. In television, video art and photography, these performances challenge the issue of representation and generate concrete peripheral Mizrahiness, realized in the visual organization of the photographic frame. Mizrahiness then transforms from ‘confrontational’ representation into a 'presence', flooding the visual sphere in our plain sight, in a process of 'becoming'. The Mizrahi desire is exerted on the plains of sound, spoken language, the body and the space where they appear. It removes from these plains the coding and stratification engendered by European dominance and rational, liberal enlightenment. This stratification, adhering to the hegemonic surface, is flooded not by way of resisting false consciousness or employing hybridity, but by way of the Mizrahi identity’s own productive, material immanent yearning. The Mizrahi desire reverberates with Mizrahi peripheral 'worlds of meaning', where post-colonial interpretation almost invariably identifies a product of internalized oppression, and a recurrence thereof, rather than a source in itself - an ‘offshoot, never a wellspring’, as Nissim Mizrachi clarifies in his recent pioneering work. The peripheral Mizrahi performance ‘unhook itself’, in Deleuze and Guattari words, from the point of subjectification and interpretation and does not correspond with the partialness, absence, and split that mark post-colonial identities.

Keywords: desire, minority, Mizrahi Jews, post-colonialism, post-liberalism, visibility, Deleuze and Guattari

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Authors: Kriangkrai Vathanalaoha

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Misery generates fear and anxiety in readers through its intense plot associated with the unpredictable emotional states of the nurse, Annie Wilkes. At the same time, she mentally and physically abuses the novelist victim, Paul Sheldon. The suspense is not only at the story level, where the violent expressions are used but also at the discourse level, where the linguistic structures may intentionally cause the reader to view language as disturbing performative. This performativity could be reflected through linguistic choices where the writer triggers a new imaginative world through experiential metafunction and schema disruption. This study explores striking excerpts from the fiction through mind style and transitivity analysis to demonstrate how the horrific experience contrasts when the protagonist and the antagonist converse extensively. The results reveal that stylistic deviation can be found at the syntactic levels, where the intensity of emotions can be apparent when the protagonist is verbally abused. In addition, transitivity can flesh out how the protagonist is expressed chiefly through the internalized process, whereas the antagonist is eminent with the externalized process. The findings suggest that the application of cognitive stylistics, such as mind style and transitivity analysis, could contribute to the mental representation of horrific reality.

Keywords: horror, mind style, misery, stylistics, transitivity

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Authors: Aude Pérard Lecomte, Georges Fokoua, Amine Mehel, Anne Tanière

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Air quality in urban areas is deteriorated by pollution, mainly due to the constant increase of the traffic of different types of ground vehicles. In particular, particulate matter pollution with important concentrations in urban areas can cause serious health issues. Characterizing and understanding particle dynamics is therefore essential to establish recommendations to improve air quality in urban areas. To analyze the effects of turbulence on particulate pollutants dispersion, the first step is to focus on the single-phase flow structure and turbulence characteristics in the wake of a heavy truck model. To achieve this, Computational Fluid Dynamics (CFD) simulations were conducted with the aim of modeling the wake airflow of a full- and reduced-scale heavy truck. The Reynolds Average Navier-Stokes (RANS) approach with the Reynolds Stress Model (RSM)as the turbulence model closure was used. The simulations highlight the apparition of a large vortex coming from the under trailer. This vortex belongs to the recirculation region, located in the near-wake of the heavy truck. These vortical structures are expected to have a strong influence on particle dynamics that are emitted by the truck.

Keywords: CDF, heavy truck, recirculation region, reduced scale

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Authors: Grzegorz Dolzyk, Sungmoon Jung

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Thin-walled tubes are commonly used as energy absorption devices for their excellent mechanical properties and high manufacturability. Techniques such as grooving and pre-folded origami shapes were introduced to circular and polygonal tubes to improve its energy absorption efficiency. This paper examines the energy absorption characteristics of circular tubes with pre-embedded curved-crease pattern. Set of numerical analyzes were conducted with different grooving patterns for tubes with various diameter (D) to thickness (t) ratio. It has been found that even very shallow grooving can positively affect thin wall tubes, leading to increased energy absorption and higher crushing load efficiency. The phenomenon is associated with nonsymmetric deformation that is usually observed for tubes with a high D/t ratio ( > 90). Grooving can redirect a natural mode of post-buckling deformation to a one with a higher number of lobes such that its beneficial and more stable. Also, the opposite effect can be achieved, and highly disrupted deformation can be a cause of reduced energy absorption capabilities. Curved-crease engraved patterns can be used to stabilize and change a form of hazardous post-buckling deformation.

Keywords: axial crushing, energy absorption, grooving, thin-wall structures

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Authors: Khaled Darwish, Islam El Madahh, Hoda Mohamed, Hadia El Hennawy

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Cloud computing has been one of the fastest growing parts in IT industry mainly in the context of the future of the web where computing, communication, and storage services are main services provided for Internet users. Mobile Cloud Computing (MCC) is gaining stream which can be used to extend cloud computing functions, services and results to the world of future mobile applications and enables delivery of a large variety of cloud application to billions of smartphones and wearable devices. This paper describes reliability for MCC by determining the ability of a system or component to function correctly under stated conditions for a specified period of time to be able to deal with the estimation and management of high levels of lifetime engineering uncertainty and risks of failure. The assessment procedures consists of determine Mean Time between Failures (MTBF), Mean Time to Failure (MTTF), and availability percentages for main components in both cloud computing and MCC structures applied on single node OpenStack installation to analyze its performance with different settings governing the behavior of participants. Additionally, we presented several factors have a significant impact on rates of change overall cloud system reliability should be taken into account in order to deliver highly available cloud computing services for mobile consumers.

Keywords: cloud computing, mobile cloud computing, reliability, availability, OpenStack

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Authors: Wenting Ye

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The biological materials evolved in nature generally exhibit interpenetrating network structures, which may offer useful inspiration for the architectural design of wear-resistant composites. Here, a strategy for designing self-lubricating medium entropy alloy (MEA) composites with high strength and excellent anti-wear performance was proposed through quasi-continuously networked in-situ carbides and graphene nanosheets. The discontinuous coating of graphene on the MEA powder surface inhibits continuous metallurgy bonding of the MEA powders during sintering, generating the typical quasi-continuously networked architecture. A good combination of mechanical properties with high fracture strength over 2 GPa and large compressive plasticity over 30% benefits from metallurgy bonding that prevents crack initiation and extension. The wear rate of an order of 10-6 m3N-1m-1 ascribing to an amorphous-crystalline nanocomposite surface, tribo-film induced by graphene, as well as the gradient worn subsurface during friction was achieved by the MEA composite, which is an order of magnitude lower than the unreinforced MEA matrix.

Keywords: in-situ carbide, tribological behavior, medium entropy alloy matrix composite, graphene

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Authors: Martin Kleynhans, Margot Soler, Gavin Quibell

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Malawi is one of the world’s poorest nations and consequently, the design of flood risk management infrastructure comes with a different set of challenges. There is a lack of good quality hydromet data, both in spatial terms and in the quality thereof and the challenge in the design of flood risk management infrastructure is compounded by the fact that maintenance is almost completely non-existent and that solutions have to be simple to be effective. Solutions should not require any further resources to remain functional after completion, and they should be resilient. They also have to be cost effective. The Lower Shire Valley of Malawi suffers from frequent flood events. Various flood risk management interventions have been designed across the valley during the course of the Shire River Basin Management Project – Phase I, and due to the data poor environment, indigenous knowledge was relied upon to a great extent for hydrological and hydraulic model calibration and verification. However, indigenous knowledge comes with the caveat that it is ‘fuzzy’ and that it can be manipulated for political reasons. The experience in the Lower Shire valley suggests that indigenous knowledge is unlikely to invent a problem where none exists, but that flood depths and extents may be exaggerated to secure prioritization of the intervention. Indigenous knowledge relies on the memory of a community and cannot foresee events that exceed past experience, that could occur differently to those that have occurred in the past, or where flood management interventions change the flow regime. This complicates communication of planned interventions to local inhabitants. Indigenous knowledge is, for the most part, intuitive, but flooding can sometimes be counter intuitive, and the rural poor may have a lower trust of technology. Due to a near complete lack of maintenance of infrastructure, infrastructure has to be designed with no moving parts and no requirement for energy inputs. This precludes pumps, valves, flap gates and sophisticated warning systems. Designs of dykes during this project included ‘flood warning spillways’, that double up as pedestrian and animal crossing points, which provide warning of impending dangerous water levels behind dykes to residents before water levels that could cause a possible dyke failure are reached. Locally available materials and erosion protection using vegetation were used wherever possible to keep costs down.

Keywords: design of dykes in low-income countries, flood warning spillways, indigenous knowledge, Malawi

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Authors: Mokshida Bhat

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This paper examines the representation of patriarchy in the movies 'Qala' and 'Black Swan' and how it affects the mental health of women. Both movies portray female characters who are subject to patriarchal attitudes and structures that limit their choices and opportunities and contribute to negative mental health outcomes. In 'Qala' the central character Qala confronts the patriarchal attitudes of her family and community, which contribute to feelings of frustration and despair. In 'Black Swan' the main character Nina is subject to the demands and expectations of a patriarchal system that leads to anxiety, paranoia, and disconnection from her own body and emotions. Both movies highlight the harmful impact of patriarchal attitudes on women's mental health, including feelings of disempowerment, objectification, and self-doubt. The paper suggests that these negative outcomes can be addressed through a rejection of patriarchal norms and an assertion of one's own agency and identity. Overall, this paper demonstrates the importance of recognizing the role of patriarchy in contributing to mental health struggles for women and the need for more diverse and empowering representations of women in media.

Keywords: patriarchy, mental health, depression, PTSD, mental health in Indian cinema, patriarchy in Indian cinema, feminism and patriarchy, sexism

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Authors: Sevda Engin, Ugur Buyuk, Necmettin Marasli

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Directional solidification of eutectic alloys attracts considerable attention because of microhardness, tensile strength, and electrical resistivity influenced by eutectic structures. In this research, we examined processing of Al–Si–Fe (Al–11.7wt.%Si–1wt.%Fe) eutectic by directional solidification. The alloy was prepared by vacuum furnace and directionally solidified in Bridgman-type equipment. During the directional solidification process, the growth rates utilized varied from 8.25 m/s to 164.80 m/s. The Al–Si–Fe system showed an eutectic transformation, which resulted in the matrix Al, Si and Al5SiFe plate phases. The eutectic spacing between (λ_Si-λ_Si, λ_(Al_5 SiFe)-λ_(Al_5 SiFe)) was measured. Additionally, the microhardness, tensile strength, and electrical resistivity of the alloy were determined using directionally solidified samples. The effects of growth rates on microhardness, tensile strength, and electrical resistivity for directionally solidified Al–Si–Fe eutectic alloy were investigated, and the relationships between them were experimentally obtained. It was found that the microhardness, tensile strength, and electrical resistivity were affected by both eutectic spacing and the solidification parameter.

Keywords: directional solidification, aluminum alloy, microstructure, electrical properties, tensile test, hardness test

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Authors: B. Yanıktepe, C. Özalp, B. Şahin

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Delta wing planform is an essential aerodynamic configuration, which could be effectively used at relatively high angles of attack than conventional wings in subsonic flow conditions. The flow over delta wings can be characterized by a pair of leading edge vortices emanating from wing apex. Boundary layer separation causes these vortical structures formed by rolling up of viscous flow sheet. This flow separation mechanism is occurred due to angle of attack and sharp leading edges of the delta wing. Therefore, complexity and variety in planform designs rise to catch the best under abnormal flow conditions. The present experimental study investigates the near surface flow structure and aerodynamic flow characteristics of X-45 type non-slender delta wing planform using dye visualization, Stereoscopic Particle Image Velocimetry (stereo-PIV). The instantaneous images are acquired on the plan-view plane within 5o≤α≤20o to calculate the time-averaged flow data. It can be concluded that vortical flow with a pair of well-defined LEVs over X-45 develop at very low angles of attack, secondary vortex are also evident and form close to the wing surface similar to delta and lambda planforms. The stall occurs at an angle of attack α=32o.

Keywords: aerodynamic, delta wing, PIV, vortex breakdown

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Authors: Branimir Jurun, Elza Jurun

Abstract:

The focus of this paper is the description of an instrument called 'Quattuor 45' and defining of wave pressure measurement. Special attention is given to measurement of wave pressure created by the wind speed increasing obtained with the instrument 'Quattuor 45' in the investigated area. The study begins with respect to theoretical attitudes and numerous up to date investigations related to the waves approaching the coast. The detailed schematic view of the instrument is enriched with pictures from ground plan and side view. Horizontal stability of the instrument is achieved by mooring which relies on two concrete blocks. Vertical wave peak monitoring is ensured by one float above the instrument. The synthesis of horizontal stability and vertical wave peak monitoring allows to create a representative database for wave pressure measuring. Instrument ‘Quattuor 45' is named according to the way the database is received. Namely, the electronic part of the instrument consists of the main chip ‘Arduino', its memory, four load cells with the appropriate modules and the wind speed sensor 'Anemometers'. The 'Arduino' chip is programmed to store two data from each load cell and two data from the anemometer on SD card each second. The next part of the research is dedicated to data processing. All measured results are stored automatically in the database and after that detailed processing is carried out in the MS Excel. The result of the wave pressure measurement is synthesized by the unit of measurement kN/m². This paper also suggests a graphical presentation of the results by multi-line graph. The wave pressure is presented on the left vertical axis, while the wind speed is shown on the right vertical axis. The time of measurement is displayed on the horizontal axis. The paper proposes an algorithm for wind speed measurements showing the results for two characteristic winds in the Adriatic Sea, called 'Bura' and 'Jugo'. The first of them is the northern wind that reaches high speeds, causing low and extremely steep waves, where the pressure of the wave is relatively weak. On the other hand, the southern wind 'Jugo' has a lower speed than the northern wind, but due to its constant duration and constant speed maintenance, it causes extremely long and high waves that cause extremely high wave pressure.

Keywords: instrument, measuring unit, waves pressure metering, wind seed measurement

Procedia PDF Downloads 198

Authors: Dhekra Khazri, Hakim Gabtni

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Because of Sidi Bouzid water table overexploitation, this study aims at integrating geophysical methods to determinate aquifers geometry assessing their geological situation and geophysical characteristics. However in highly tectonic zones controlled by Atlassic structural features with NE-SW major directions (central Tunisia), Bouguer gravimetric responses of some areas can be as much dominated by the regional structural tendency, as being non-identified or either defectively interpreted such as the case of Sidi Bouzid basin. This issue required a residual gravity anomaly elaboration isolating the Sidi Bouzid basin gravity response ranging between -8 and -14 mGal and crucial for its aquifers geometry characterization. Several gravity techniques helped constructing the Sidi Bouzid basin's residual gravity anomaly, such as Upwards continuation compared to polynomial regression trends and power spectrum analysis detecting deep basement sources at (3km), intermediate (2km) and shallow sources (1km). A 3D Euler Deconvolution was also performed detecting deepest accidents trending NE-SW, N-S and E-W with depth values reaching 5500 m and delineating the main outcropping structures of the study area. Further gravity treatments highlighted the subsurface geometry and structural features of Sidi Bouzid basin over Horizontal and vertical gradient, and also filters based on them such as Tilt angle and Source Edge detector locating rooted edges or peaks from potential field data detecting a new E-W lineament compartmentalizing the Sidi Bouzid gutter into two unequally residual anomaly and subsiding domains. This subsurface morphology is also detected by the used 2D seismic reflection sections defining the Sidi Bouzid basin as a deep gutter within a tectonic set of negative flower structures, and collapsed and tilted blocks. Furthermore, these structural features were confirmed by forward gravity modeling process over several modeled residual gravity profiles crossing the main area. Sidi Bouzid basin (central Tunisia) is also of a big interest cause of the unknown total thickness and the undefined substratum of its siliciclastic Tertiary package, and its aquifers unbounded structural subsurface features and deep accidents. The Combination of geological, hydrogeological and geophysical methods is then of an ultimate need. Therefore, a geophysical methods integration based on gravity survey supporting available seismic data through forward gravity modeling, enhanced lateral and vertical extent definition of the basin's complex sedimentary fill via 3D gravity models, improved depth estimation by a depth to basement modeling approach, and provided 3D isochronous seismic mapping visualization of the basin's Tertiary complex refining its geostructural schema. A subsurface basin geomorphology mapping, over an ultimate matching between the basin's residual gravity map and the calculated theoretical signature map, was also displayed over the modeled residual gravity profiles. An ultimate multidisciplinary geophysical study of the Sidi Bouzid basin aquifers can be accomplished via an aeromagnetic survey and a 4D Microgravity reservoir monitoring offering temporal tracking of the target aquifer's subsurface fluid dynamics enhancing and rationalizing future groundwater exploitation in this arid area of central Tunisia.

Keywords: aquifer geometry, geophysics, 3D gravity modeling, improved depths, source edge detector

Procedia PDF Downloads 283

Authors: Hyo-In Koh, Anders Nordborg, Alex Sievi, Chun-Kwon Park

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The noise source for the interior room of the high speed train is constituted by the rolling contact between the wheel and the rail, aerodynamic noise and structure-borne sound generated through the vibrations of bogie, connection points to the carbody. Air-borne sound is radiated through the panels and structures into the interior room of the trains. The high-speed lines are constructed with slab track systems and many tunnels. The interior noise level and the frequency characteristics vary according to types of the track structure and the infrastructure. In this paper the main sound sources and the transfer paths are studied to find out the contribution characteristics of the sources to the interior noise of a high-speed rail vehicle. For the identification of the acoustic power of each parts of the rolling noise sources a calculation model of wheel/rail noise is developed and used. For the analysis of the transmission of the sources to the interior noise noise and vibration are measured during the operation of the vehicle. According to operation speeds, the mainly contributed sources and the paths could be analyzed. Results of the calculations on the source generation and the results of the measurement with a high-speed train are shown and discussed.

Keywords: rail vehicle, high-speed, interior noise, noise source

Procedia PDF Downloads 400

Authors: Amanda Kenny, Virginia Dickson-Swift, Jane Farmer, Sarah Larkins, Karen Carlisle, Helen Hickson

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Rural ECOH (Engaging Communities in Oral Health) is a collaborative project that connects policy makers, service providers and community members. The aim of the project is to empower community members to determine what is important for their community and to design the services that they need. This three-year project is currently underway in six rural communities across Australia. This study is specifically focused on Remote Services Futures (RSF), an evidence-based method of community participation that was developed in Scotland. The findings highlight the complexities of community participation in health service planning. We assumed that people living in rural communities would welcome participation in oral health planning and engage with their community to discuss these issues. We found that to understand the relationships between community members and health service providers, it was essential to identify the formal and informal community leaders and to engage stakeholders from the various community governance structures. Our study highlights the sometimes ‘messiness’ of decision making in rural communities as well as ways to ensure that community members have the training and practical skills necessary to participate in community decision making.

Keywords: community participation, health planning, rural ECOH, Remote Services Futures

Procedia PDF Downloads 539

Authors: Amal Alatar

Abstract:

The architectural legacy is considered a significant factor, which left its features on the shape of buildings and historical and archaeological sites all over the world. In this framework, this paper focuses on Umm Qais town, located in Northern Jordan, which includes archaeological remains of the ancient Decapolis city of Gadara, still the witness of the originality and architectural identity of the city. 3D modeling is a public asset and a valuable resource for cultural heritage. This technique allows the possibility to make accurate representations of objects, structures, and surfaces. Hence, these representations increase valuable assets when thinking about cultural heritage. The Heritage Building Information Modeling (HBIM) is considered an effective tool to represent information on Cultural Heritage (CH) which can be used for documentation, restoration, conservation, presentation, and research purposes. Therefore, this paper focus on the interdisciplinary project of the virtualization of the West Theater in Gadara (Umm Qais) for 3D documentation and structural studies. The derived 3D model of the cultural heritage is the basis for further archaeological studies; the challenges of the work stay in the acquisition, processing, and integration of the multi-resolution data as well as their interactive visualization.

Keywords: archaeology, 3D modeling, Umm Qais, culture heritage, Jordan

Procedia PDF Downloads 101

Authors: Tarek M. Alguhane, Ayman H. Khalil, M. N. Fayed, Ayman M. Ismail

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The elastic period has a primary role in the seismic assessment of buildings. Reliable calculations and/or estimates of the fundamental frequency of a building and its site are essential during analysis and design process. Various code formulas based on empirical data are generally used to estimate the fundamental frequency of a structure. For existing structures, in addition to code formulas and available analytical tools such as modal analyses, various methods of testing including ambient and forced vibration testing procedures may be used to determine dynamic characteristics. In this study, the dynamic properties of the 32 buildings located in the Madinah of Saudi Arabia were identified using ambient motions recorded at several, spatially-distributed locations within each building. Ambient vibration measurements of buildings have been analyzed and the fundamental longitudinal and transverse periods for all tested buildings are presented. The fundamental mode of vibration has been compared in plots with codes formulae (Saudi Building Code, EC8, and UBC1997). The results indicate that measured periods of existing buildings are shorter than that given by most empirical code formulas. Recommendations are given based on the common design and construction practice in Madinah city.

Keywords: ambient vibration, fundamental period, RC buildings, infill walls

Procedia PDF Downloads 263