Search results for: interface shape
2432 Utility Analysis of API Economy Based on Multi-Sided Platform Markets Model
Authors: Mami Sugiura, Shinichi Arakawa, Masayuki Murata, Satoshi Imai, Toru Katagiri, Motoyoshi Sekiya
Abstract:
API (Application Programming Interface) economy, where many participants join/interact and form the economy, is expected to increase collaboration between information services through API, and thereby, it is expected to increase market value from the service collaborations. In this paper, we introduce API evaluators, which are the activator of API economy by reviewing and/or evaluating APIs, and develop a multi-sided API economy model that formulates interactions among platform provider, API developers, consumers, and API evaluators. By obtaining the equilibrium that maximizes utility of all participants, the impact of API evaluators on the utility of participants in the API economy is revealed. Numerical results show that, with the existence of API evaluators, the number of developers and consumers increase by 1.5% and the utility of platformer increases by 2.3%. We also discuss the strategies of platform provider to maximize its utility under the existence of API evaluators.Keywords: API economy, multi-sided markets, API evaluator, platform, platform provider
Procedia PDF Downloads 1862431 Precursor Muscle Cell’s Phenotype under Compression in a Biomimetic Mechanical Niche
Authors: Fatemeh Abbasi, Arne Hofemeier, Timo Betz
Abstract:
Muscle growth and regeneration critically depend on satellite cells (SCs) which are muscle stem cells located between the basal lamina and myofibres. Upon damage, SCs become activated, enter the cell cycle, and give rise to myoblasts that form new myofibres, while a sub-population self-renew and re-populate the muscle stem cell niche. In aged muscle as well as in certain muscle diseases such as muscular dystrophy, some of the SCs lose their regenerative ability. Although it is demonstrated that the chemical composition of SCs quiescent niche is different from the activated niche, the mechanism initially activated in the SCs remains unknown. While extensive research efforts focused on potential chemical activation, no such factor has been identified to the author’s best knowledge. However, it is substantiated that niche mechanics affects SCs behaviors, such as stemness and engraftment. We hypothesize that mechanical stress in the healthy niche (homeostasis) is different from the regenerative niche and that this difference could serve as an early signal activating SCs upon fiber damage. To investigate this hypothesis, we develop a biomimetic system to reconstitute both, the mechanical and the chemical environment of the SC niche. Cells will be confined between two elastic polyacrylamide (PAA) hydrogels with controlled elastic moduli and functionalized surface chemistry. By controlling the distance between the PAA hydrogel surfaces, we vary the compression forces exerted by the substrates on the cells, while the lateral displacement of the upper hydrogel will create controlled shear forces. To establish such a system, a simplified system is presented. We engineered a sandwich-like configuration of two elastic PAA layer with stiffnesses between 1 and 10 kPa and confined a precursor myoblast cell line (C2C12) in between these layers. Our initial observations in this sandwich model indicate that C2C12 cells show different behaviors under mechanical compression if compared to a control one-layer gel without compression. Interestingly, this behavior is stiffness-dependent. While the shape of C2C12 cells in the sandwich consisting of two stiff (10 kPa) layers was much more elongated, showing almost a neuronal phenotype, the cell shape in a sandwich situation consisting of one stiff and one soft (1 kPa) layer was more spherical. Surprisingly, even in proliferation medium and at very low cell density, the sandwich situation stimulated cell differentiation with increased striation and myofibre formation. Such behavior is commonly found for confluent cells in differentiation medium. These results suggest that mechanical changes in stiffness and applied pressure might be a relevant stimulation for changes in muscle cell behavior.Keywords: C2C12 cells, compression, force, satellite cells, skeletal muscle
Procedia PDF Downloads 1242430 Fractional Order Controller Design for Vibration Attenuation in an Airplane Wing
Authors: Birs Isabela, Muresan Cristina, Folea Silviu, Prodan Ovidiu
Abstract:
The wing is one of the most important parts of an airplane because it ensures stability, sustenance and maneuverability of the airplane. Because of its shape, the airplane wing can be simplified to a smart beam. Active vibration suppression is realized using piezoelectric actuators that are mounted on the surface of the beam. This work presents a tuning procedure of fractional order controllers based on a graphical approach of the frequency domain representation. The efficacy of the method is proven by practically testing the controller on a laboratory scale experimental stand.
Keywords: fractional order control, piezoelectric actuators, smart beam, vibration suppression
Procedia PDF Downloads 3152429 Non-Linear Causality Inference Using BAMLSS and Bi-CAM in Finance
Authors: Flora Babongo, Valerie Chavez
Abstract:
Inferring causality from observational data is one of the fundamental subjects, especially in quantitative finance. So far most of the papers analyze additive noise models with either linearity, nonlinearity or Gaussian noise. We fill in the gap by providing a nonlinear and non-gaussian causal multiplicative noise model that aims to distinguish the cause from the effect using a two steps method based on Bayesian additive models for location, scale and shape (BAMLSS) and on causal additive models (CAM). We have tested our method on simulated and real data and we reached an accuracy of 0.86 on average. As real data, we considered the causality between financial indices such as S&P 500, Nasdaq, CAC 40 and Nikkei, and companies' log-returns. Our results can be useful in inferring causality when the data is heteroskedastic or non-injective.Keywords: causal inference, DAGs, BAMLSS, financial index
Procedia PDF Downloads 1512428 Modeling of Global Solar Radiation on a Horizontal Surface Using Artificial Neural Network: A Case Study
Authors: Laidi Maamar, Hanini Salah
Abstract:
The present work investigates the potential of artificial neural network (ANN) model to predict the horizontal global solar radiation (HGSR). The ANN is developed and optimized using three years meteorological database from 2011 to 2013 available at the meteorological station of Blida (Blida 1 university, Algeria, Latitude 36.5°, Longitude 2.81° and 163 m above mean sea level). Optimal configuration of the ANN model has been determined by minimizing the Root Means Square Error (RMSE) and maximizing the correlation coefficient (R2) between observed and predicted data with the ANN model. To select the best ANN architecture, we have conducted several tests by using different combinations of parameters. A two-layer ANN model with six hidden neurons has been found as an optimal topology with (RMSE=4.036 W/m²) and (R²=0.999). A graphical user interface (GUI), was designed based on the best network structure and training algorithm, to enhance the users’ friendliness application of the model.Keywords: artificial neural network, global solar radiation, solar energy, prediction, Algeria
Procedia PDF Downloads 4992427 Characteization and Optimization of S-Parameters of Microwave Circuits
Authors: N. Ourabia, M. Boubaker Ourabia
Abstract:
An approach for modeling and numerical simulation of passive planar structures using the edge line concept is developed. With this method, we develop an efficient modeling technique for microstrip discontinuities. The technique obtains closed form expressions for the equivalent circuits which are used to model these discontinuities. Then, it would be easy to handle and to characterize complicated structures like T and Y junctions, truncated junctions, arbitrarily shaped junctions, cascading junctions and more generally planar multiport junctions. Another advantage of this method is that the edge line concept for arbitrary shape junctions operates with real parameters circuits. The validity of the method was further confirmed by comparing our results for various discontinuities (bend, filters) with those from HFSS as well as from other published sources.Keywords: optimization, CAD analysis, microwave circuits, S-parameters
Procedia PDF Downloads 4542426 Modelling of Multi-Agent Systems for the Scheduling of Multi-EV Charging from Power Limited Sources
Authors: Manan’Iarivo Rasolonjanahary, Chris Bingham, Nigel Schofield, Masoud Bazargan
Abstract:
This paper presents the research and application of model predictive scheduled charging of electric vehicles (EV) subject to limited available power resource. To focus on algorithm and operational characteristics, the EV interface to the source is modelled as a battery state equation during the charging operation. The researched methods allow for the priority scheduling of EV charging in a multi-vehicle regime and when subject to limited source power availability. Priority attribution for each connected EV is described. The validity of the developed methodology is shown through the simulation of different scenarios of charging operation of multiple connected EVs including non-scheduled and scheduled operation with various numbers of vehicles. Performance of the developed algorithms is also reported with the recommendation of the choice of suitable parameters.Keywords: model predictive control, non-scheduled, power limited sources, scheduled and stop-start battery charging
Procedia PDF Downloads 1582425 Structural Safety of Biocomposites under Cracking: A Fracture Analytical Approach using the Gғ-Concept
Authors: Brandtner-Hafner Martin
Abstract:
Biocomposites have established themselves as a sustainable material class in the industry. Their advantages include lower density, lower price, and easier recycling compared to conventional materials. Now there are a variety of ways to measure their technical performance. One possibility is mechanical tests, which are widely used and standardized. However, these provide only very limited insights into damage capacity, which is particularly problematic under cracking conditions. To overcome such shortcomings, experimental tests were performed applying the fracture energetically GF-concept to study the structural safety of the interface under crack opening (mode-I loading). Two different types of biocomposites based on extruded henequen-fibers (NFRP) and wood-particles (WPC) in an HDPE matrix were evaluated. The results show that the fracture energy values obtained are higher than those given in the literature. This suggests that alternatives to previous linear elastic testing methods are needed to perform authentic safety evaluations of green plastics.Keywords: biocomposites, structural safety, Gғ-concept, fracture analysis
Procedia PDF Downloads 1592424 Sea-Spray Calculations Using the MESO-NH Model
Authors: Alix Limoges, William Bruch, Christophe Yohia, Jacques Piazzola
Abstract:
A number of questions arise concerning the long-term impact of the contribution of marine aerosol fluxes generated at the air-sea interface on the occurrence of intense events (storms, floods, etc.) in the coastal environment. To this end, knowledge is needed on sea-spray emission rates and the atmospheric dynamics of the corresponding particles. Our aim is to implement the mesoscale model MESO-NH on the study area using an accurate sea-spray source function to estimate heat fluxes and impact on the precipitations. Based on an original and complete sea-spray source function, which covers a large size spectrum since taking into consideration the sea-spray produced by both bubble bursting and surface tearing process, we propose a comparison between model simulations and experimental data obtained during an oceanic scientific cruise on board the navy ship Atalante. The results show the relevance of the sea-spray flux calculations as well as their impact on the heat fluxes and AOD.Keywords: atmospheric models, sea-spray source, sea-spray dynamics, aerosols
Procedia PDF Downloads 1492423 Heat and Mass Transfer Study of Supercooled Large Droplet Icing
Authors: Du Yanxia, Stephan E. Bansmer, Gui Yewei, Xiao Guangming, Yang Xiaofeng
Abstract:
The heat and mass transfer characteristics of icing coupled with film flow is studied and the coupled model of the thermal behavior with the flow simulation by single-step method is developed. The behavior of ice and water was analyzed. The results show that under supercooled large droplet (SLD) icing conditions, the film flow is an important phonomena in icing accretion process. The pressure gradient, gravity and shear stress are the main factors affecting the film flow on icing surface, which has important influence on the shape and rate of icing. To predict SLD ice accretion accurately, the heat and mass transfer of ice and film flow should be taken into account.Keywords: SLD, aircraft, icing, heat and mass transfer
Procedia PDF Downloads 6342422 [Keynote Talk]: Ultrasound Assisted Synthesis of ZnO of Different Morphologies by Solvent Variation
Authors: Durata Haciu, Berti Manisa, Ozgur Birer
Abstract:
ZnO nanoparticles have been synthesized by ultrasonic irradiation from simple linear alcohols and water/ethanolic mixtures, at 50 oC. By changing the composition of the solvent, the shape could be altered. While no product was obtained from methanolic solutions, in ethanol, sheet like lamellar structures prevail.n-propanol and n-butanol resulted in needle like structures. The morphology of ZnO could be thus tailored in a simple way, by varying the solvent, under ultrasonic irradiation, in a relatively less time consuming method. Variation of the morphology and size of Zn also provides a means for modulating the band-gap. Although the chemical effects of ultrasound do not come from direct interaction with molecular species, the high energy derived from acoustic cavitation creates a unique interaction of energy and matter with great potential for synthesis.Keywords: ultrasound, ZnO, linear alcohols, morphology
Procedia PDF Downloads 2422421 Effect of Flow Holes on Heat Release Performance of Extruded-Type Heat Sink
Authors: Jung Hyun Kim, Gyo Woo Lee
Abstract:
In this study, the enhancement of the heat release performance of an extruded-type heat sink to prepare the large-capacity solar inverter thru the flow holes in the base plate near the heat sources was investigated. Optimal location and number of the holes in the baseplate were determined by using a commercial computation program. The heat release performance of the shape-modified heat sink was measured experimentally and compared with that of the simulation. The heat sink with 12 flow holes in the 18-mm-thick base plate has a 8.1% wider heat transfer area, a 2.5% more mass flow of air, and a 2.7% higher heat release rate than those of the original heat sink. Also, the surface temperature of the base plate was lowered 1.5°C by the holes.Keywords: heat sink, forced convection, heat transfer, performance evaluation, flow holes
Procedia PDF Downloads 5332420 Reduced Power Consumption by Randomization for DSI3
Authors: David Levy
Abstract:
The newly released Distributed System Interface 3 (DSI3) Bus Standard specification defines 3 modulation levels from which 16 valid symbols are coded. This structure creates power consumption variations depending on the transmitted data of a factor of more than 2 between minimum and maximum. The power generation unit has to consider therefore the worst case maximum consumption all the time and be built accordingly. This paper proposes a method to reduce both the average current consumption and worst case current consumption. The transmitter randomizes the data using several pseudo-random sequences. It then estimates the energy consumption of the generated frames and selects to transmit the one which consumes the least. The transmitter also prepends the index of the pseudo-random sequence, which is not randomized, to allow the receiver to recover the original data using the correct sequence. We show that in the case that the frame occupies most of the DSI3 synchronization period, we achieve average power consumption reduction by up to 13% and the worst case power consumption is reduced by 17.7%.Keywords: DSI3, energy, power consumption, randomization
Procedia PDF Downloads 5382419 Networked Radar System to Increase Safety of Urban Railroad Crossing
Authors: Sergio Saponara, Luca Fanucci, Riccardo Cassettari, Ruggero Piernicola, Marco Righetto
Abstract:
The paper presents an innovative networked radar system for detection of obstacles in a railway level crossing scenario. This Monitoring System (MS) is able to detect moving or still obstacles within the railway level crossing area automatically, avoiding the need of human presence for surveillance. The MS is also connected to the National Railway Information and Signaling System to communicate in real-time the level crossing status. The architecture is compliant with the highest Safety Integrity Level (SIL4) of the CENELEC standard. The number of radar sensors used is configurable at set-up time and depends on how large the level crossing area can be. At least two sensors are expected and up four can be used for larger areas. The whole processing chain that elaborates the output sensor signals, as well as the communication interface, is fully-digital, was designed in VHDL code and implemented onto a Xilinx Virtex 6.Keywords: radar for safe mobility, railroad crossing, railway, transport safety
Procedia PDF Downloads 4802418 An Erudite Technique for Face Detection and Recognition Using Curvature Analysis
Authors: S. Jagadeesh Kumar
Abstract:
Face detection and recognition is an authoritative technology for image database management, video surveillance, and human computer interface (HCI). Face recognition is a rapidly nascent method, which has been extensively discarded in forensics such as felonious identification, tenable entree, and custodial security. This paper recommends an erudite technique using curvature analysis (CA) that has less false positives incidence, operative in different light environments and confiscates the artifacts that are introduced during image acquisition by ring correction in polar coordinate (RCP) method. This technique affronts mean and median filtering technique to remove the artifacts but it works in polar coordinate during image acquisition. Investigational fallouts for face detection and recognition confirms decent recitation even in diagonal orientation and stance variation.Keywords: curvature analysis, ring correction in polar coordinate method, face detection, face recognition, human computer interaction
Procedia PDF Downloads 2872417 Vibrations of Springboards: Mode Shape and Time Domain Analysis
Authors: Stefano Frassinelli, Alessandro Niccolai, Riccardo E. Zich
Abstract:
Diving is an important Olympic sport. In this sport, the effective performance of the athlete is related to his capability to interact correctly with the springboard. In fact, the elevation of the jump and the correctness of the dive are influenced by the vibrations of the board. In this paper, the vibrations of the springboard will be analyzed by means of typical tools for vibration analysis: Firstly, a modal analysis will be done on two different models of the springboard, then, these two model and another one will be analyzed with a time analysis, done integrating the equations of motion od deformable bodies. All these analyses will be compared with experimental data measured on a real springboard by means of a 6-axis accelerometer; these measurements are aimed to assess the models proposed. The acquired data will be analyzed both in frequency domain and in time domain.Keywords: springboard analysis, modal analysis, time domain analysis, vibrations
Procedia PDF Downloads 4602416 Development of Ultrasounf Probe Holder for Automatic Scanning Asymmetric Reflector
Authors: Nabilah Ibrahim, Hafiz Mohd Zaini, Wan Fatin Liyana Mutalib
Abstract:
Ultrasound equipment or machine is capable to scan in two dimensional (2D) areas. However there are some limitations occur during scanning an object. The problem will occur when scanning process that involving the asymmetric object. In this project, the ultrasound probe holder for asymmetric reflector scanning in 3D image is proposed to make easier for scanning the phantom or object that has asymmetric shape. Initially, the constructed asymmetric phantom that construct will be used in 2D scanning. Next, the asymmetric phantom will be interfaced by the movement of ultrasound probe holder using the Arduino software. After that, the performance of the ultrasound probe holder will be evaluated by using the various asymmetric reflector or phantom in constructing a 3D imageKeywords: ultrasound 3D images, axial and lateral resolution, asymmetric reflector, Arduino software
Procedia PDF Downloads 5602415 Optimized Approach for Secure Data Sharing in Distributed Database
Authors: Ahmed Mateen, Zhu Qingsheng, Ahmad Bilal
Abstract:
In the current age of technology, information is the most precious asset of a company. Today, companies have a large amount of data. As the data become larger, access to data for some particular information is becoming slower day by day. Faster data processing to shape it in the form of information is the biggest issue. The major problems in distributed databases are the efficiency of data distribution and response time of data distribution. The security of data distribution is also a big issue. For these problems, we proposed a strategy that can maximize the efficiency of data distribution and also increase its response time. This technique gives better results for secure data distribution from multiple heterogeneous sources. The newly proposed technique facilitates the companies for secure data sharing efficiently and quickly.Keywords: ER-schema, electronic record, P2P framework, API, query formulation
Procedia PDF Downloads 3332414 Protein Tertiary Structure Prediction by a Multiobjective Optimization and Neural Network Approach
Authors: Alexandre Barbosa de Almeida, Telma Woerle de Lima Soares
Abstract:
Protein structure prediction is a challenging task in the bioinformatics field. The biological function of all proteins majorly relies on the shape of their three-dimensional conformational structure, but less than 1% of all known proteins in the world have their structure solved. This work proposes a deep learning model to address this problem, attempting to predict some aspects of the protein conformations. Throughout a process of multiobjective dominance, a recurrent neural network was trained to abstract the particular bias of each individual multiobjective algorithm, generating a heuristic that could be useful to predict some of the relevant aspects of the three-dimensional conformation process formation, known as protein folding.Keywords: Ab initio heuristic modeling, multiobjective optimization, protein structure prediction, recurrent neural network
Procedia PDF Downloads 2062413 Movement of Metallic Inclusions in the Volume of Synthetic Diamonds at High Pressure and High Temperature in the Temperature Gradient Field
Authors: P. I. Yachevskaya, S. A. Terentiev, M. S. Kuznetsov
Abstract:
Several synthetic HPHT diamonds with metal inclusions have been studied. To have possibility of investigate the movement and transformation of the inclusions in the volume of the diamond the samples parallele-piped like shape has been made out of diamond crystals. The calculated value of temperature gradient in the samples of diamond which was placed in high-pressure cell was about 5-10 grad/mm. Duration of the experiments was in range 2-16 hours. All samples were treated several times. It has been found that the volume (dimensions) of inclusions, temperature, temperature gradient and the crystallographic orientation of the samples in the temperature field affects the movement speed of inclusions. Maximum speed of inclusions’ movement reached a value 150 µm/h.Keywords: diamond, inclusions, temperature gradient, HPHT
Procedia PDF Downloads 5102412 Pixel Façade: An Idea for Programmable Building Skin
Authors: H. Jamili, S. Shakiba
Abstract:
Today, one of the main concerns of human beings is facing the unpleasant changes of the environment. Buildings are responsible for a significant amount of natural resources consumption and carbon emissions production. In such a situation, this thought comes to mind that changing each building into a phenomenon of benefit to the environment. A change in a way that each building functions as an element that supports the environment, and construction, in addition to answering the need of humans, is encouraged, the way planting a tree is, and it is no longer seen as a threat to alive beings and the planet. Prospect: Today, different ideas of developing materials that can smartly function are realizing. For instance, Programmable Materials, which in different conditions, can respond appropriately to the situation and have features of modification in shape, size, physical properties and restoration, and repair quality. Studies are to progress having this purpose to plan for these materials in a way that they are easily available, and to meet this aim, there is no need to use expensive materials and high technologies. In these cases, physical attributes of materials undertake the role of sensors, wires and actuators then materials will become into robots itself. In fact, we experience robotics without robots. In recent decades, AI and technology advances have dramatically improving the performance of materials. These achievements are a combination of software optimizations and physical productions such as multi-materials 3D printing. These capabilities enable us to program materials in order to change shape, appearance, and physical properties to interact with different situations. nIt is expected that further achievements like Memory Materials and Self-learning Materials are also added to the Smart Materials family, which are affordable, available, and of use for a variety of applications and industries. From the architectural standpoint, the building skin is significantly considered in this research, concerning the noticeable surface area the buildings skin have in urban space. The purpose of this research would be finding a way that the programmable materials be used in building skin with the aim of having an effective and positive interaction. A Pixel Façade would be a solution for programming a building skin. The Pixel Facadeincludes components that contain a series of attributes that help buildings for their needs upon their environmental criteria. A PIXEL contains series of smart materials and digital controllers together. It not only benefits its physical properties, such as control the amount of sunlight and heat, but it enhances building performance by providing a list of features, depending on situation criteria. The features will vary depending on locations and have a different function during the daytime and different seasons. The primary role of a PIXEL FAÇADE can be defined as filtering pollutions (for inside and outside of the buildings) and providing clean energy as well as interacting with other PIXEL FACADES to estimate better reactions.Keywords: building skin, environmental crisis, pixel facade, programmable materials, smart materials
Procedia PDF Downloads 892411 Development of Web-Based Remote Desktop to Provide Adaptive User Interfaces in Cloud Platform
Authors: Shuen-Tai Wang, Hsi-Ya Chang
Abstract:
Cloud virtualization technologies are becoming more and more prevalent, cloud users usually encounter the problem of how to access to the virtualized remote desktops easily over the web without requiring the installation of special clients. To resolve this issue, we took advantage of the HTML5 technology and developed web-based remote desktop. It permits users to access the terminal which running in our cloud platform from anywhere. We implemented a sketch of web interface following the cloud computing concept that seeks to enable collaboration and communication among users for high performance computing. Given the development of remote desktop virtualization, it allows to shift the user’s desktop from the traditional PC environment to the cloud platform, which is stored on a remote virtual machine rather than locally. This proposed effort has the potential to positively provide an efficient, resilience and elastic environment for online cloud service. This is also made possible by the low administrative costs as well as relatively inexpensive end-user terminals and reduced energy expenses.Keywords: virtualization, remote desktop, HTML5, cloud computing
Procedia PDF Downloads 3392410 Study of the Tribological Behavior of a Sliding Contact Brass-Steel Couple with Electrical Current
Authors: C. Boubechou, A. Bouchoucha, H. Zaidi
Abstract:
The aim of this paper is to study the tribological behavior of a dynamic contact steel-brass couple with electric current. This study looks at a dry contact brass-steel couple where friction and wear are studied in terms of mechanical and electrical parameters. For this reason, a tribometer, pin-rotary disc is used in an atmospheric atmosphere. The test parameters are as follows: the normal load (5-30N), the sliding speed (0.1 to 0.5 m / s) and the electric current (3-10A). The duration of each test is 30 minutes. The experimental results show that these parameters have a significant effect on the tribological behavior of the couple studied. The discussion of results is based on observations, using an optical microscope, MEB and a profilometer, worn surfaces and interface phenomena resulting from the process of sliding contact.Keywords: brass-steel couple, dry friction, electrical current, morphology, normal load, sliding speeds, wear
Procedia PDF Downloads 2682409 Defining of the Shape of the Spine Using Moiré Method in Case of Patients with Scheuermann Disease
Authors: Petra Balla, Gabor Manhertz, Akos Antal
Abstract:
Nowadays spinal deformities are very frequent problems among teenagers. Scheuermann disease is a one dimensional deformity of the spine, but it has prevalence over 11% of the children. A traditional technology, the moiré method was used by us for screening and diagnosing this type of spinal deformity. A LabVIEW program has been developed to evaluate the moiré pictures of patients with Scheuermann disease. Two different solutions were tested in this computer program, the extreme and the inflexion point calculation methods. Effects using these methods were compared and according to the results both solutions seemed to be appropriate. Statistical results showed better efficiency in case of the extreme search method where the average difference was only 6,09⁰.Keywords: spinal deformity, picture evaluation, Moiré method, Scheuermann disease, curve detection, Moiré topography
Procedia PDF Downloads 3522408 Regenerated Cellulose Prepared by Using NaOH/Urea
Authors: Lee Chiau Yeng, Norhayani Othman
Abstract:
Regenerated cellulose fiber is fabricated in the NaOH/urea aqueous solution. In this work, cellulose is dissolved in 7 .wt% NaOH/12 .wt% urea in the temperature of -12 °C to prepare regenerated cellulose. Thermal and structure properties of cellulose and regenerated cellulose was compared and investigated by Field Emission Scanning Electron Microscopy (FeSEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric analysis (TGA), and Differential Scanning Calorimetry. Results of FeSEM revealed that the regenerated cellulose fibers showed a more circular shape with irregular size due to fiber agglomeration. FTIR showed the difference in between the structure of cellulose and the regenerated cellulose fibers. In this case, regenerated cellulose fibers have a cellulose II crystalline structure with lower degree of crystallinity. Regenerated cellulose exhibited better thermal stability than the cellulose.Keywords: regenerated cellulose, cellulose, NaOH, urea
Procedia PDF Downloads 4312407 Three-Dimensional Numerical Investigation for Reinforced Concrete Slabs with Opening
Authors: Abdelrahman Elsehsah, Hany Madkour, Khalid Farah
Abstract:
This article presents a 3-D modified non-linear elastic model in the strain space. The Helmholtz free energy function is introduced with the existence of a dissipation potential surface in the space of thermodynamic conjugate forces. The constitutive equation and the damage evolution were derived as well. The modified damage has been examined to model the nonlinear behavior of reinforced concrete (RC) slabs with an opening. A parametric study with RC was carried out to investigate the impact of different factors on the behavior of RC slabs. These factors are the opening area, the opening shape, the place of opening, and the thickness of the slabs. And the numerical results have been compared with the experimental data from literature. Finally, the model showed its ability to be applied to the structural analysis of RC slabs.Keywords: damage mechanics, 3-D numerical analysis, RC, slab with opening
Procedia PDF Downloads 1742406 Landscape Pattern Evolution and Optimization Strategy in Wuhan Urban Development Zone, China
Abstract:
With the rapid development of urbanization process in China, its environmental protection pressure is severely tested. So, analyzing and optimizing the landscape pattern is an important measure to ease the pressure on the ecological environment. This paper takes Wuhan Urban Development Zone as the research object, and studies its landscape pattern evolution and quantitative optimization strategy. First, remote sensing image data from 1990 to 2015 were interpreted by using Erdas software. Next, the landscape pattern index of landscape level, class level, and patch level was studied based on Fragstats. Then five indicators of ecological environment based on National Environmental Protection Standard of China were selected to evaluate the impact of landscape pattern evolution on the ecological environment. Besides, the cost distance analysis of ArcGIS was applied to simulate wildlife migration thus indirectly measuring the improvement of ecological environment quality. The result shows that the area of land for construction increased 491%. But the bare land, sparse grassland, forest, farmland, water decreased 82%, 47%, 36%, 25% and 11% respectively. They were mainly converted into construction land. On landscape level, the change of landscape index all showed a downward trend. Number of patches (NP), Landscape shape index (LSI), Connection index (CONNECT), Shannon's diversity index (SHDI), Aggregation index (AI) separately decreased by 2778, 25.7, 0.042, 0.6, 29.2%, all of which indicated that the NP, the degree of aggregation and the landscape connectivity declined. On class level, the construction land and forest, CPLAND, TCA, AI and LSI ascended, but the Distribution Statistics Core Area (CORE_AM) decreased. As for farmland, water, sparse grassland, bare land, CPLAND, TCA and DIVISION, the Patch Density (PD) and LSI descended, yet the patch fragmentation and CORE_AM increased. On patch level, patch area, Patch perimeter, Shape index of water, farmland and bare land continued to decline. The three indexes of forest patches increased overall, sparse grassland decreased as a whole, and construction land increased. It is obvious that the urbanization greatly influenced the landscape evolution. Ecological diversity and landscape heterogeneity of ecological patches clearly dropped. The Habitat Quality Index continuously declined by 14%. Therefore, optimization strategy based on greenway network planning is raised for discussion. This paper contributes to the study of landscape pattern evolution in planning and design and to the research on spatial layout of urbanization.Keywords: landscape pattern, optimization strategy, ArcGIS, Erdas, landscape metrics, landscape architecture
Procedia PDF Downloads 1652405 Design and Fabrication of Electricity Generating Speed Breaker
Authors: Haider Aamir, Muhammad Ali Khalid
Abstract:
Electricity harvesting speed bump (EHSB) is speed breaker of conventional shape, but the difference is that it is not fixed, rather it moves up and down, and electricity can be generated from its vibrating motion. This speed bump consists of an upper cover which will move up and down, a shaft mechanism which will be used to drive the generator and a rack and pinion mechanism which will connect the cover and shaft. There is a spring mechanism to return the cover to its initial state when a vehicle has passed over the bump. Produced energy in the past was up to 80 Watts. For this purpose, a clutch mechanism is used so that both the up-down movements of the cover can be used to drive the generator. Mechanical Motion Rectifier (MMR) mechanism ensures the conversion of both the linear motions into rotational motion which is used to drive the generator.Keywords: electricity harvesting, generator, rack and pinion, stainless steel shaft
Procedia PDF Downloads 2722404 Evaluation of Dynamic Behavior of a Rotor-Bearing System in Operating Conditions
Authors: Mohammad Hadi Jalali, Behrooz Shahriari, Mostafa Ghayour, Saeed Ziaei-Rad, Shahram Yousefi
Abstract:
Most flexible rotors can be considered as beam-like structures. In many cases, rotors are modeled as one-dimensional bodies, made basically of beam-like shafts with rigid bodies attached to them. This approach is typical of rotor dynamics, both analytical and numerical, and several rotor dynamic codes, based on the finite element method, follow this trend. In this paper, a finite element model based on Timoshenko beam elements is utilized to analyze the lateral dynamic behavior of a certain rotor-bearing system in operating conditions.Keywords: finite element method, Timoshenko beam elements, operational deflection shape, unbalance response
Procedia PDF Downloads 4282403 Heat Transfer Studies for LNG Vaporization During Underwater LNG Releases
Authors: S. Naveen, V. Sivasubramanian
Abstract:
A modeling theory is proposed to consider the vaporization of LNG during its contact with water following its release from an underwater source. The spillage of LNG underwater can lead to a decrease in the surface temperature of water and subsequent freezing. This can in turn affect the heat flux distribution from the released LNG onto the water surrounding it. The available models predict the rate of vaporization considering the surface of contact as a solid wall, and considering the entire phenomena as a solid-liquid operation. This assumption greatly under-predicted the overall heat transfer on LNG water interface. The vaporization flux would first decrease during the film boiling, followed by an increase during the transition boiling and a steady decrease during the nucleate boiling. A superheat theory is introduced to enhance the accuracy in the prediction of the heat transfer between LNG and water. The work suggests that considering the superheat theory can greatly enhance the prediction of LNG vaporization on underwater releases and also help improve the study of overall thermodynamics.Keywords: evaporation rate, heat transfer, LNG vaporization, underwater LNG release
Procedia PDF Downloads 439