Search results for: fixed point analysis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 31573

Search results for: fixed point analysis

30373 Bread Quality Improvement with Special Novel Additives

Authors: Mónika Bartalné-Berceli, Eszter Izsó, Szilveszter Gergely, András Salgó

Abstract:

Nowadays a significant portion of the Earth's population does not have access to healthy food. Either because they can not afford them or because they do not know which they are. The aim of the VIIth Framework CHANCE project (Nr. 266331) supported by the European Union has been to develop relatively cheap food favorable from nutritional point of view and has acceptable quality for consumers. Within the project we dealt with manufacturing of bread belonging to basic foods. We had examined the enrichment of bread products with four kinds of bran, with a special milling product of grain industry (aleurone flour) and with a soy-based sprouted additive. The applied concentration of the six mentioned additives has been optimized and the physical and sensory properties of the bread products were monitored. The weight of the enriched breads increased slightly, however the volume and height decreased slightly compared to the corresponding data of the control bread. The composition of the final product is favorable affected by these additives having highly preferred composition from nutritional point of view.

Keywords: bread products, brans, YASO, aleurone flour

Procedia PDF Downloads 386
30372 Hardware-in-the-Loop Test for Automatic Voltage Regulator of Synchronous Condenser

Authors: Ha Thi Nguyen, Guangya Yang, Arne Hejde Nielsen, Peter Højgaard Jensen

Abstract:

Automatic voltage regulator (AVR) plays an important role in volt/var control of synchronous condenser (SC) in power systems. Test AVR performance in steady-state and dynamic conditions in real grid is expensive, low efficiency, and hard to achieve. To address this issue, we implement hardware-in-the-loop (HiL) test for the AVR of SC to test the steady-state and dynamic performances of AVR in different operating conditions. Startup procedure of the system and voltage set point changes are studied to evaluate the AVR hardware response. Overexcitation, underexcitation, and AVR set point loss are tested to compare the performance of SC with the AVR hardware and that of simulation. The comparative results demonstrate how AVR will work in a real system. The results show HiL test is an effective approach for testing devices before deployment and is able to parameterize the controller with lower cost, higher efficiency, and more flexibility.

Keywords: automatic voltage regulator, hardware-in-the-loop, synchronous condenser, real time digital simulator

Procedia PDF Downloads 248
30371 Analysis of Moment Rotation Curve for Steel Beam Column Joint

Authors: A. J. Shah, G. R. Vesmawala

Abstract:

Connections perform a fundamental role in the steel structures as global behaviour. In order to evaluate the real influence of the physical and geometrical parameters that control their behaviour, many experimental tests and analysis have been developed but a definitive answer to the problem in question still stands. Here, various configurations of bolts were tried and the resulting moment rotation (M-θ) curves were plotted. The connection configuration is such that two bolts are located above each of the flanges and beside each of the webs. The model considers the combined effects of prying action, the formation of yield lines, and failures due to punching shear and beam section failure. For many types of connections, the stiffness at the service load level falls somewhere in between the fully restrained and simple limits and designers need to account for its behaviour. The (M-θ) curves are generally assumed to be the best characterization of connection behaviour. The moment rotation curves are generally derived from experiments on cantilever type specimens. The moments are calculated directly from the statics of the specimen, while the rotations are measured over a distance typically equal to the point of loading. Thus, this paper establishes the relationship between M-θ behaviour of different types of connections tested and presents the relative strength of various possible arrangements of bolts.

Keywords: bolt, moment, rotation, stiffness, connections

Procedia PDF Downloads 388
30370 Computational Analysis of Variation in Thrust of Oblique Detonation Ramjet Engine With Adaptive Inlet

Authors: Aditya, Ganapati Joshi, Vinod Kumar

Abstract:

IN THE MODERN-WARFARE ERA, THE PRIME REQUIREMENT IS A HIGH SPEED AND MACH NUMBER. WHEN THE MISSILES STRIKE IN THE HYPERSONIC REGIME THE OPPONENT CAN DETECT IT WITH THE ANTI-DEFENSE SYSTEM BUT CAN NOT STOP IT FROM CAUSING DAMAGE. SO, TO ACHIEVE THE SPEEDS OF THIS LEVEL THERE ARE TWO ENGINES THAT ARE AVAILABLE WHICH CAN WORK IN THIS REGION ARE RAMJET AND SCRAMJET. THE PROBLEM WITH RAMJET STARTS TO OCCUR WHEN MACH NUMBER EXCEEDS 4 AS THE STATIC PRESSURE AT THE INLET BECOMES EQUAL TO THE EXIT PRESSURE. SO, SCRAMJET ENGINE DEALS WITH THIS PROBLEM AS IT NEARLY HAS THE SAME WORKING BUT HERE THE FLOW IS NOT MUCH SLOWED DOWN AS COMPARED TO RAMJET IN THE DIFFUSER BUT IT SUFFERS FROM THE PROBLEMS SUCH AS INLET BUZZ, THERMAL CHOCKING, MIXING OF FUEL AND OXIDIZER, THERMAL HEATING, AND MANY MORE. HERE THE NEW ENGINE IS DEVELOPED ON THE SAME PRINCIPLE AS THE SCRAMJET ENGINE BUT BURNING HAPPENS DUE TO DETONATION INSTEAD OF DEFLAGRATION. THE PROBLEM WITH THE ENGINE STARTS WHEN THE MACH NUMBER BECOMES VARIABLE AND THE INLET GEOMETRY IS FIXED AND THIS LEADS TO INLET SPILLAGE WHICH WILL AFFECT THE THRUST ADVERSELY. SO, HERE ADAPTIVE INLET IS MADE OF SHAPE MEMORY ALLOYS WHICH WILL ENHANCE THE INLET MASS FLOW RATE AS WELL AS THRUST.

Keywords: detonation, ramjet engine, shape memory alloy, ignition delay, shock-boundary layer interaction, eddy dissipation, asymmetric nozzle

Procedia PDF Downloads 99
30369 Novel Ultrasensitive Point of Care Device for Diagnosis of Human Schistosomiasis Mansoni

Authors: Ibrahim Aly, Waleed Elawamy, Hanan Taher, Amira Matar

Abstract:

Schistosomiasis is infection with blood flukes of the genus Schistosoma, which are acquired trans-cutaneously by swimming or wading in contaminated freshwater. The present study was proposed to produce ultra-sensitive, field-friendly high-throughput rapid immunochromatography diagnostic device for accurate detection of asymptomatic parasite carriers in schistosomiasis pre-elimination settings.For assessing diagnostic potential of rapid device, 50 blood samples from patients with schistosomiasis mansoni, 29 other proven parasitic diseases and 25 blood samples as negative control were from healthy individuals were used. The sensitivity of Quantitative antigen-capture nano-ELISAwas 82 %, and specificity was 87.1 %, where the sensitivity of Nano Dot- ELISA was 86 % and specificity was 90.7 %. The sensitivity of diagnostic device was 78 % and specificity was 85.2 %, with PPV and NPV of 86.2 % and 83.1 %, respectively.The Point of care device resulted in a good performance for the diagnosis of low-intensity infections, it was able to identify 19 out of 25 (76 %) individuals with ⩽7 eggs, 10 out of 14 individuals (71.4 %) with 11–99 eggs and 100 % of individuals with 100–399 eggs.

Keywords: schistosomiasis, immunochromatography, naon-dot-ELISa, diagnostis device

Procedia PDF Downloads 72
30368 Thermal Stress and Computational Fluid Dynamics Analysis of Coatings for High-Temperature Corrosion

Authors: Ali Kadir, O. Anwar Beg

Abstract:

Thermal barrier coatings are among the most popular methods for providing corrosion protection in high temperature applications including aircraft engine systems, external spacecraft structures, rocket chambers etc. Many different materials are available for such coatings, of which ceramics generally perform the best. Motivated by these applications, the current investigation presents detailed finite element simulations of coating stress analysis for a 3- dimensional, 3-layered model of a test sample representing a typical gas turbine component scenario. Structural steel is selected for the main inner layer, Titanium (Ti) alloy for the middle layer and Silicon Carbide (SiC) for the outermost layer. The model dimensions are 20 mm (width), 10 mm (height) and three 1mm deep layers. ANSYS software is employed to conduct three types of analysis- static structural, thermal stress analysis and also computational fluid dynamic erosion/corrosion analysis (via ANSYS FLUENT). The specified geometry which corresponds to corrosion test samples exactly is discretized using a body-sizing meshing approach, comprising mainly of tetrahedron cells. Refinements were concentrated at the connection points between the layers to shift the focus towards the static effects dissipated between them. A detailed grid independence study is conducted to confirm the accuracy of the selected mesh densities. To recreate gas turbine scenarios; in the stress analysis simulations, static loading and thermal environment conditions of up to 1000 N and 1000 degrees Kelvin are imposed. The default solver was used to set the controls for the simulation with the fixed support being set as one side of the model while subjecting the opposite side to a tabular force of 500 and 1000 Newtons. Equivalent elastic strain, total deformation, equivalent stress and strain energy were computed for all cases. Each analysis was duplicated twice to remove one of the layers each time, to allow testing of the static and thermal effects with each of the coatings. ANSYS FLUENT simulation was conducted to study the effect of corrosion on the model under similar thermal conditions. The momentum and energy equations were solved and the viscous heating option was applied to represent improved thermal physics of heat transfer between the layers of the structures. A Discrete Phase Model (DPM) in ANSYS FLUENT was employed which allows for the injection of continuous uniform air particles onto the model, thereby enabling an option for calculating the corrosion factor caused by hot air injection (particles prescribed 5 m/s velocity and 1273.15 K). Extensive visualization of results is provided. The simulations reveal interesting features associated with coating response to realistic gas turbine loading conditions including significantly different stress concentrations with different coatings.

Keywords: thermal coating, corrosion, ANSYS FEA, CFD

Procedia PDF Downloads 134
30367 Reduplication In Urdu-Hindi Nonsensical Words: An OT Analysis

Authors: Riaz Ahmed Mangrio

Abstract:

Reduplication in Urdu-Hindi affects all major word categories, particles, and even nonsensical words. It conveys a variety of meanings, including distribution, emphasis, iteration, adjectival and adverbial. This study will primarily discuss reduplicative structures of nonsensical words in Urdu-Hindi and then briefly look at some examples from other Indo-Aryan languages to introduce the debate regarding the same structures in them. The goal of this study is to present counter-evidence against Keane (2005: 241), who claims “the base in the cases of lexical and phrasal echo reduplication is always independently meaningful”. However, Urdu-Hindi reduplication derives meaningful compounds from nonsensical words e.g. gũ mgũ (A) ‘silent and confused’ and d̪əb d̪əb-a (N) ‘one’s fear over others’. This needs a comprehensive examination to see whether and how the various structures form patterns of a base-reduplicant relationship or, rather, they are merely sub lexical items joining together to form a word pattern of any grammatical category in content words. Another interesting theoretical question arises within the Optimality framework: in an OT analysis, is it necessary to identify one of the two constituents as the base and the other as reduplicant? Or is it best to consider this a pattern, but then how does this fit in with an OT analysis? This may be an even more interesting theoretical question. Looking for the solution to such questions can serve to make an important contribution. In the case at hand, each of the two constituents is an independent nonsensical word, but their echo reduplication is nonetheless meaningful. This casts significant doubt upon Keane’s (2005: 241) observation of some examples from Hindi and Tamil reduplication that “the base in cases of lexical and phrasal echo reduplication is always independently meaningful”. The debate on the point becomes further interesting when the triplication of nonsensical words in Urdu-Hindi e.g. aẽ baẽ ʃaẽ (N) ‘useless talk’ is also seen, which is equally important to discuss. The example is challenging to Harrison’s (1973) claim that only the monosyllabic verbs in their progressive forms reduplicate twice to result in triplication, which is not the case with the example presented. The study will consist of a thorough descriptive analysis of the data for the purpose of documentation, and then there will be OT analysis.

Keywords: reduplication, urdu-hindi, nonsensical, optimality theory

Procedia PDF Downloads 73
30366 CFD Simulation for Development of Cooling System in a Cooking Oven

Authors: V. Jagadish, Mathiyalagan V.

Abstract:

Prediction of Door Touch temperature of a Cooking Oven using CFD Simulation. Self-Clean cycle is carried out in Cooking ovens to convert food spilling into ashes which makes cleaning easy. During this cycle cavity of oven is exposed to high temperature around 460 C. At this operating point the user may prone to touch the Door surfaces, Side Shield, Control Panel. To prevent heat experienced by user, cooling system is built in oven. The most effective cooling system is developed with existing design constraints through CFD Simulations. Cross Flow fan is used for Cooling system due to its cost effectiveness and it can give more air flow with low pressure drop.

Keywords: CFD, MRF, RBM, RANS, new product development, simulation, thermal analysis

Procedia PDF Downloads 151
30365 Optimal Tuning of RST Controller Using PSO Optimization for Synchronous Generator Based Wind Turbine under Three-Phase Voltage Dips

Authors: K. Tahir, C. Belfedal, T. Allaoui, C. Gerard, M. Doumi

Abstract:

In this paper, we presented an optimized RST controller using Particle Swarm Optimization (PSO) meta-heuristic technique of the active and reactive power regulation of a grid connected wind turbine based on a wound field synchronous generator. This regulation is achieved below the synchronous speed, by means of a maximum power point tracking algorithm. The control of our system is tested under typical wind variations and parameters variation, fault grid condition by simulation. Some results are presented and discussed to prove simplicity and efficiency of the WRSG control for WECS. On the other hand, according to simulation results, variable speed driven WRSG is not significantly impacted in fault conditions.

Keywords: wind energy, particle swarm optimization, wound rotor synchronous generator, power control, RST controller, maximum power point tracking

Procedia PDF Downloads 445
30364 Experimental and Numerical Investigation of Fracture Behavior of Foamed Concrete Based on Three-Point Bending Test of Beams with Initial Notch

Authors: M. Kozłowski, M. Kadela

Abstract:

Foamed concrete is known for its low self-weight and excellent thermal and acoustic properties. For many years, it has been used worldwide for insulation to foundations and roof tiles, as backfill to retaining walls, sound insulation, etc. However, in the last years it has become a promising material also for structural purposes e.g. for stabilization of weak soils. Due to favorable properties of foamed concrete, many interests and studies were involved to analyze its strength, mechanical, thermal and acoustic properties. However, these studies do not cover the investigation of fracture energy which is the core factor governing the damage and fracture mechanisms. Only limited number of publications can be found in literature. The paper presents the results of experimental investigation and numerical campaign of foamed concrete based on three-point bending test of beams with initial notch. First part of the paper presents the results of a series of static loading tests performed to investigate the fracture properties of foamed concrete of varying density. Beam specimens with dimensions of 100×100×840 mm with a central notch were tested in three-point bending. Subsequently, remaining halves of the specimens with dimensions of 100×100×420 mm were tested again as un-notched beams in the same set-up with reduced distance between supports. The tests were performed in a hydraulic displacement controlled testing machine with a load capacity of 5 kN. Apart from measuring the loading and mid-span displacement, a crack mouth opening displacement (CMOD) was monitored. Based on the load – displacement curves of notched beams the values of fracture energy and tensile stress at failure were calculated. The flexural tensile strength was obtained on un-notched beams with dimensions of 100×100×420 mm. Moreover, cube specimens 150×150×150 mm were tested in compression to determine the compressive strength. Second part of the paper deals with numerical investigation of the fracture behavior of beams with initial notch presented in the first part of the paper. Extended Finite Element Method (XFEM) was used to simulate and analyze the damage and fracture process. The influence of meshing and variation of mechanical properties on results was investigated. Numerical models simulate correctly the behavior of beams observed during three-point bending. The numerical results show that XFEM can be used to simulate different fracture toughness of foamed concrete and fracture types. Using the XFEM and computer simulation technology allow for reliable approximation of load–bearing capacity and damage mechanisms of beams made of foamed concrete, which provides some foundations for realistic structural applications.

Keywords: foamed concrete, fracture energy, three-point bending, XFEM

Procedia PDF Downloads 297
30363 Electrical Analysis of Corn Oil as an Alternative to Mineral Oil in Power Transformers

Authors: E. Taslak, C. Kocatepe, O. Arıkan, C. F. Kumru

Abstract:

In insulation and cooling of power transformers various liquids are used. Mineral oils have wide availability and low cost. However, they have a poor biodegradability potential and lower fire point in comparison with other insulating liquids. Use of a liquid having high biodegradability is important due to environmental consideration. This paper investigates edible corn oil as an alternative to mineral oil. Various properties of mineral and corn oil like breakdown voltage, dissipation factor, relative dielectric constant, power loss and resistivity were measured according to different standards.

Keywords: breakdown voltage, corn oil, dissipation factor, mineral oil, power loss, relative dielectric constant, resistivity

Procedia PDF Downloads 568
30362 Current Design Approach for Seismic Resistant Automated Rack Supported Warehouses: Strong Points and Critical Aspects

Authors: Agnese Natali, Francesco Morelli, Walter Salvatore

Abstract:

Automated Rack Supported Warehouses (ARSWs) are structures currently designed as steel racks. Even if there are common characteristics, there are differences that don’t allow to adopt the same design approach. Aiming to highlight the factors influencing the design and the behavior of ARSWs, a set of 5 structures designed by 5 European companies specialized in this field is used to perform both a critical analysis of the design approaches and the assessment of the seismic performance, which is used to point out the criticalities and the necessity of new design philosophy.

Keywords: steel racks, automated rack supported warehouse, thin walled cold-formed elements, seismic assessment

Procedia PDF Downloads 159
30361 Performance Analysis of a Planar Membrane Humidifier for PEM Fuel Cell

Authors: Yu-Hsuan Chang, Jian-Hao Su, Chen-Yu Chen, Wei-Mon Yan

Abstract:

In this work, the experimental measurement was applied to examine the membrane type and flow field design on the performance of a planar membrane humidifier. The performance indexes were used to evaluate the planar membrane humidifier. The performance indexes of the membrane humidifier include the dew point approach temperature (DPAT), water recovery ratio (WRR), water flux (J) and pressure loss (P). The experiments contain mainly three parts. In the first part, a single membrane humidifier was tested using different flow field under different dry-inlet temperatures. The measured results show that the dew point approach temperature decreases with increasing the depth of flow channel at the same width of flow channel. However, the WRR and J reduce with an increase in the dry air-inlet temperature. The pressure loss tests indicate that pressure loss decreases with increasing the hydraulic diameter of flow channel, resulting from an increase in Darcy friction. Owing to the comparison of humidifier performances and pressure losses, the flow channel of width W=1 and height H=1.5 was selected as the channel design of the multi-membrane humidifier in the second part of experiment. In the second part, the multi-membrane humidifier was used to evaluate the humidification performance under different relative humidity and flow rates. The measurement results indicate that the humidifier at both lower temperature and relative humidity of inlet dry air have higher DPAT but lower J and WRR. In addition, the counter flow approach has better mass and heat transfer performance than the parallel flow approach. Moreover, the effects of dry air temperature, relative humidity and humidification approach are not significant to the pressure loss in the planar membrane humidifier. For the third part, different membranes were tested in this work in order to find out which kind membrane is appropriate for humidifier.

Keywords: water management, planar membrane humidifier, heat and mass transfer, pressure loss, PEM fuel cell

Procedia PDF Downloads 203
30360 Simple Multipath Compensation for Frequency Modulated Signals: A Case of Radio Frequency vs. Quadrature Baseband

Authors: Lusungu Ndovi

Abstract:

Radio propagation from point-to-point is affected by the physical channel in many ways. A signal arriving at a destination travels through a number of different paths which are referred to as multi-paths. Research in this area of wireless communications has progressed well over the years with the research taking different angles of focus. By this is meant that some researchers focus on ways of reducing or eluding Multipath effects whilst others focus on ways of mitigating the effects of Multipath through compensation schemes. Baseband processing is seen as one field of signal processing that is cardinal to the advancement of software-defined radio technology. This has led to wide research into the carrying out certain algorithms at baseband. This paper considers compensating for Multipath for Frequency Modulated signals. The compensation process is carried out at Radio frequency (RF) and at Quadrature baseband (QBB) and the results are compared. Simulations are carried out using MatLab so as to show the benefits of working at lower QBB frequencies than at RF.

Keywords: quadrature baseband, qadio frequency, qultipath compensation, frequency qodulation, signal processing

Procedia PDF Downloads 477
30359 Improving Communication System through Router Configuration: The Nigerian Navy Experience

Authors: Saidu I. Rambo, Emmanuel O. Ibam, Sunday O. Adewale

Abstract:

The configuration of routers for effective communication in the Nigerian Navy (NN) enables the navy to improve on the current communication systems. The current system is faced with challenges that make the systems partially effective. The major implementation of the system is to configure routers using hierarchical model and obtaining a VSAT option on C-band platform. These routers will act as a link between Naval Headquarters and the Commands under it. The routers main responsibilities are to forward packets from source location to destination using a Link State Routing Protocol (LSRP). Also using the Point to Point Protocol (PPP), creates a strong encrypted password using Challenge Handshake Authentication Protocol (CHAP) which uses one-way hash function of Message Digest 5 (MD5) to provide complete protection against hackers/intruders. Routers can be configured using a Linux operating system or internet work operating system in the Microsoft platform. With this, system packets can be forwarded to various locations more effectively than the present system being used.

Keywords: C-band, communication, router, VSAT

Procedia PDF Downloads 363
30358 Density Determination of Liquid Niobium by Means of Ohmic Pulse-Heating for Critical Point Estimation

Authors: Matthias Leitner, Gernot Pottlacher

Abstract:

Experimental determination of critical point data like critical temperature, critical pressure, critical volume and critical compressibility of high-melting metals such as niobium is very rare due to the outstanding experimental difficulties in reaching the necessary extreme temperature and pressure regimes. Experimental techniques to achieve such extreme conditions could be diamond anvil devices, two stage gas guns or metal samples hit by explosively accelerated flyers. Electrical pulse-heating under increased pressures would be another choice. This technique heats thin wire samples of 0.5 mm diameter and 40 mm length from room temperature to melting and then further to the end of the stable phase, the spinodal line, within several microseconds. When crossing the spinodal line, the sample explodes and reaches the gaseous phase. In our laboratory, pulse-heating experiments can be performed under variation of the ambient pressure from 1 to 5000 bar and allow a direct determination of critical point data for low-melting, but not for high-melting metals. However, the critical point also can be estimated by extrapolating the liquid phase density according to theoretical models. A reasonable prerequisite for the extrapolation is the existence of data that cover as much as possible of the liquid phase and at the same time exhibit small uncertainties. Ohmic pulse-heating was therefore applied to determine thermal volume expansion, and from that density of niobium over the entire liquid phase. As a first step, experiments under ambient pressure were performed. The second step will be to perform experiments under high-pressure conditions. During the heating process, shadow images of the expanding sample wire were captured at a frame rate of 4 × 105 fps to monitor the radial expansion as a function of time. Simultaneously, the sample radiance was measured with a pyrometer operating at a mean effective wavelength of 652 nm. To increase the accuracy of temperature deduction, spectral emittance in the liquid phase is also taken into account. Due to the high heating rates of about 2 × 108 K/s, longitudinal expansion of the wire is inhibited which implies an increased radial expansion. As a consequence, measuring the temperature dependent radial expansion is sufficient to deduce density as a function of temperature. This is accomplished by evaluating the full widths at half maximum of the cup-shaped intensity profiles that are calculated from each shadow image of the expanding wire. Relating these diameters to the diameter obtained before the pulse-heating start, the temperature dependent volume expansion is calculated. With the help of the known room-temperature density, volume expansion is then converted into density data. The so-obtained liquid density behavior is compared to existing literature data and provides another independent source of experimental data. In this work, the newly determined off-critical liquid phase density was in a second step utilized as input data for the estimation of niobium’s critical point. The approach used, heuristically takes into account the crossover from mean field to Ising behavior, as well as the non-linearity of the phase diagram’s diameter.

Keywords: critical point data, density, liquid metals, niobium, ohmic pulse-heating, volume expansion

Procedia PDF Downloads 216
30357 Free Shape Optimisation of Cold Formed Steel Sections

Authors: Mina Mortazavi, Pezhman Sharafi

Abstract:

Cold-formed steel sections are popular construction materials as structural or non-structural elements. The objective of this paper is to propose an optimisation method for open cross sections targeting the maximum nominal axial strength. The cross sections considered in the optimisation process should all meet a determined critical global buckling load to be considered as a candidate for optimisation process. The maximum dimensions of the cross section are fixed and limited into a predefined rectangular area. The optimisation process is repeated for different available coil thicknesses of 1 mm, 2.5 mm and 3 mm to determine the optimum thickness according to the cross section buckling behaviour. A simple-simple boundary is assumed as end conditions. The number of folds is limited to 20 folds to prevent extra complicated sections. The global buckling load is considered as Euler load and is determined according to the moment of inertia of the cross-section with a constant length. The critical buckling loads are obtained using Finite Strip Method. The results of the optimisation analysis are provided, and the optimum cross-section within the considered range is determined.

Keywords: shape optimisation, buckling, cold formed steel, finite strip method

Procedia PDF Downloads 398
30356 Design, Optimize the Damping System for Optical Scanning Equipment

Authors: Duy Nhat Tran, Van Tien Pham, Quang Trung Trinh, Tien Hai Tran, Van Cong Bui

Abstract:

In recent years, artificial intelligence and the Internet of Things have experienced significant advancements. Collecting image data and real-time analysis and processing of tasks have become increasingly popular in various aspects of life. Optical scanning devices are widely used to observe and analyze different environments, whether fixed outdoors, mounted on mobile devices, or used in unmanned aerial vehicles. As a result, the interaction between the physical environment and these devices has become more critical in terms of safety. Two commonly used methods for addressing these challenges are active and passive approaches. Each method has its advantages and disadvantages, but combining both methods can lead to higher efficiency. One solution is to utilize direct-drive motors for position control and real-time feedback within the operational range to determine appropriate control parameters with high precision. If the maximum motor torque is smaller than the inertial torque and the rotor reaches the operational limit, the spring system absorbs the impact force. Numerous experiments have been conducted to demonstrate the effectiveness of device protection during operation.

Keywords: optical device, collision safety, collision absorption, precise mechanics

Procedia PDF Downloads 59
30355 Environmental Assessment of Roll-to-Roll Printed Smart Label

Authors: M. Torres, A. Moulay, M. Zhuldybina, M. Rozel, N. D. Trinh, C. Bois

Abstract:

Printed electronics are a fast-growing market as their applications cover a large range of industrial needs, their production cost is low, and the additive printing techniques consume less materials than subtractive manufacturing methods used in traditional electronics. With the growing demand for printed electronics, there are concerns about their harmful and irreversible contribution to the environment. Indeed, it is estimated that 80% of the environmental load of a product is determined by the choices made at the conception stage. Therefore, examination through a life cycle approach at the developing stage of a novel product is the best way to identify potential environmental issues and make proactive decisions. Life cycle analysis (LCA) is a comprehensive scientific method to assess the environmental impacts of a product in its different stages of life: extraction of raw materials, manufacture and distribution, use, and end-of-life. Impacts and major hotspots are identified and evaluated through a broad range of environmental impact categories of the ReCiPe (H) middle point method. At the conception stage, the LCA is a tool that provides an environmental point of view on the choice of materials and processes and weights-in on the balance between performance materials and eco-friendly materials. Using the life cycle approach, the current work aims to provide a cradle-to-grave life cycle assessment of a roll-to-roll hybrid printed smart label designed for the food cold chain. Furthermore, this presentation will present the environmental impact of metallic conductive inks, a comparison with promising conductive polymers, evaluation of energy vs. performance of industrial printing processes, a full assessment of the impact from the smart label applied on a cellulosic-based substrate during the recycling process and the possible recovery of precious metals and rare earth elements.

Keywords: Eco-design, label, life cycle assessment, printed electronics

Procedia PDF Downloads 159
30354 The Influence of Celebrity Endorsement on Consumers’ Attitude and Purchas Intention Towards Skincare Products in Malaysia

Authors: Tew Leh Ghee

Abstract:

The study's goal is to determine how celebrity endorsement affects Malaysian consumers' attitudes and intentions to buy skincare products. Since customers now largely rely on celebrity endorsement to influence purchasing decisions in almost every business, celebrity endorsement is not, in reality, a new phenomenon. Even though the market for skincare products has a vast potential to be exploited, corporations have yet to seize this niche via celebrity endorsement. Basically, there hasn't been much study done to recognize the significance of celebrity endorsement in this industry. This research combined descriptive and quantitative methods with a self-administered survey as the primary data-gathering tool. All of the characteristics under study were measured using a 5-point Likert scale, and the questionnaire was written in English. A convenience sample method was used to choose respondents, and 360 sets of valid questionnaires were gathered for the study's statistical analysis. Preliminary statistical analyses were analyzed using SPSS version 20.0 (Statistical Package for the Social Sciences). The backdrop of the respondents' demographics was examined using descriptive analysis. All concept assessments' validity and reliability were examined using exploratory factor analysis, item-total statistics, and reliability statistics. Pearson correlation and regression analysis were used, respectively, to assess relationships and impacts between the variables under study. The research showed that, apart from competence, celebrity endorsements of skincare products in Malaysia had a favorable impact on attitudes and purchase intentions as evaluated by attractiveness and dependability. The research indicated that the most significant element influencing attitude and buy intention was the credibility of a celebrity endorsement. The study offered implications in order to provide potential improvements of celebrity endorsement in skincare goods in Malaysia. The study's last portion includes its limits and ideas for the future.

Keywords: trustworthiness, influential, phenomenon, celebrity emdorsement

Procedia PDF Downloads 74
30353 Determination of Mercury in Gold Ores by CVAAS Method

Authors: Ratna Siti Khodijah, Mirzam Abdurrachman

Abstract:

Gold is recovered from gold ores. Within the ores, there are not only gold but also several types of precious metals. Copper, silver, and platinum group elements (ruthenium, rhodium, palladium, rhenium, osmium, and iridium) are metals commonly found in the ores. These metals combine to form an ore because they have the same properties. It is due to their position in periodic-system-of-elements are near to gold. However, the presence of mercury in every gold ore has not been mentioned, even though it is located right next to gold in the periodic-system-of-elements and they are located in the same block, d-block. Thus, it is possible that mercury is contained in the ores. Moreover, the elements of the same group with mercury—zinc and cadmium—sometimes can be found in the ores. It is suspected that mercury can not be detected because the processing of gold ores usually using fire assay method. Before the ores melting, mercury would evaporate because it has the lowest boiling point of all precious metal in the ores. Therefore, it suggested doing research on the presence of mercury in gold ores by CVAAS method. The results of this study would obtain the amount of mercury in gold ores that should be purified. So it can be produced economically if possible.

Keywords: boiling point, d-block, fire assay, precious metal

Procedia PDF Downloads 334
30352 Flow Control Optimisation Using Vortex Generators in Turbine Blade

Authors: J. Karthik, G. Vinayagamurthy

Abstract:

Aerodynamic flow control is achieved by interaction of flowing medium with corresponding structure so that its natural flow state is disturbed to delay the transition point. This paper explains the aerodynamic effect and optimized design of Vortex Generators on the turbine blade to achieve maximum flow control. The airfoil is chosen from NREL [National Renewable Energy Laboratory] S-series airfoil as they are characterized with good lift characteristics and lower noise. Vortex generators typically chosen are Ogival, Rectangular, Triangular and Tapered Fin shapes attached near leading edge. Vortex generators are typically distributed from the primary to tip of the blade section. The design wind speed is taken as 6m/s and the computational analysis is executed. The blade surface is simulated using k- ɛ SST model and results are compared with X-FOIL results. The computational results are validated using Wind Tunnel Testing of the blade corresponding to the design speed. The effect of Vortex generators on the flow characteristics is studied from the results of analysis. By comparing the computational and test results of all shapes of Vortex generators; the optimized design is achieved for effective flow control corresponding to the blade.

Keywords: flow control, vortex generators, design optimisation, CFD

Procedia PDF Downloads 401
30351 Analysis of Developments in the Understanding of In-Service Training in Turkish Public Administration: Personnel Management to Human Resource Management

Authors: Sema Müge Özdemiray

Abstract:

In line with the new public management approach to provide effective and efficient services necessary to achieve the social goals of public institutions, employees must have the knowledge and skills required by the age. In conjunction with the transition from personnel management to human resources management, it is seen that there is a change in the understanding of in-service training, the understanding of "required in-service training" has switched to the understanding of "continuous in-service training". However, in terms of in-service training in Turkey, it seems to be trouble at the point of adopting to change. The main purpose of this study is to primarily create a conceptual framework of in-service training and subsequently determine, analyze and discuss the developments and problems faced by in-service training in Turkey in the transition from personnel management to human resources management. In accordance with this purpose, the necessary data of this study were collected using qualitative approaches. Observation and document analysis was used and content analysis was performed on the data gathered in the study. The results of this study, according to data such as the number of institutions requesting in-service training, allocated budget of in-service training, the number of people participating in such training, transition of personnel management to human resources management should not lead to a paradigm shift in Turkey’s understanding of in-service training, although this is compulsory for public institutions in accordance with the law in Turkey. In-service training in Turkish public administration is still not implemented effectively and is seen as a social activity for employees and a formality for institutions.

Keywords: Human resources management, in service training, personnel management, public institutions

Procedia PDF Downloads 316
30350 Performance Assessment of Horizontal Axis Tidal Turbine with Variable Length Blades

Authors: Farhana Arzu, Roslan Hashim

Abstract:

Renewable energy is the only alternative sources of energy to meet the current energy demand, healthy environment and future growth which is considered essential for essential sustainable development. Marine renewable energy is one of the major means to meet this demand. Turbines (both horizontal and vertical) play a vital role for extraction of tidal energy. The influence of swept area on the performance improvement of tidal turbine is a vital factor to study for the reduction of relatively high power generation cost in marine industry. This study concentrates on performance investigation of variable length blade tidal turbine concept that has already been proved as an efficient way to improve energy extraction in the wind industry. The concept of variable blade length utilizes the idea of increasing swept area through the turbine blade extension when the tidal stream velocity falls below the rated condition to maximize energy capture while blade retracts above rated condition. A three bladed horizontal axis variable length blade horizontal axis tidal turbine was modelled by modifying a standard fixed length blade turbine. Classical blade element momentum theory based numerical investigation has been carried out using QBlade software to predict performance. The results obtained from QBlade were compared with the available published results and found very good agreement. Three major performance parameters (i.e., thrust, moment, and power coefficients) and power output for different blade extensions were studied and compared with a standard fixed bladed baseline turbine at certain operational conditions. Substantial improvement in performance coefficient is observed with the increase in swept area of the turbine rotor. Power generation is found to increase in great extent when operating at below rated tidal stream velocity reducing the associated cost per unit electric power generation.

Keywords: variable length blade, performance, tidal turbine, power generation

Procedia PDF Downloads 273
30349 Thermodynamics of Aqueous Solutions of Organic Molecule and Electrolyte: Use Cloud Point to Obtain Better Estimates of Thermodynamic Parameters

Authors: Jyoti Sahu, Vinay A. Juvekar

Abstract:

Electrolytes are often used to bring about salting-in and salting-out of organic molecules and polymers (e.g. polyethylene glycols/proteins) from the aqueous solutions. For quantification of these phenomena, a thermodynamic model which can accurately predict activity coefficient of electrolyte as a function of temperature is needed. The thermodynamics models available in the literature contain a large number of empirical parameters. These parameters are estimated using lower/upper critical solution temperature of the solution in the electrolyte/organic molecule at different temperatures. Since the number of parameters is large, inaccuracy can bethe creep in during their estimation, which can affect the reliability of prediction beyond the range in which these parameters are estimated. Cloud point of solution is related to its free energy through temperature and composition derivative. Hence, the Cloud point measurement can be used for accurate estimation of the temperature and composition dependence of parameters in the model for free energy. Hence, if we use a two pronged procedure in which we first use cloud point of solution to estimate some of the parameters of the thermodynamic model and determine the rest using osmotic coefficient data, we gain on two counts. First, since the parameters, estimated in each of the two steps, are fewer, we achieve higher accuracy of estimation. The second and more important gain is that the resulting model parameters are more sensitive to temperature. This is crucial when we wish to use the model outside temperatures window within which the parameter estimation is sought. The focus of the present work is to prove this proposition. We have used electrolyte (NaCl/Na2CO3)-water-organic molecule (Iso-propanol/ethanol) as the model system. The model of Robinson-Stokes-Glukauf is modified by incorporating the temperature dependent Flory-Huggins interaction parameters. The Helmholtz free energy expression contains, in addition to electrostatic and translational entropic contributions, three Flory-Huggins pairwise interaction contributions viz., and (w-water, p-polymer, s-salt). These parameters depend both on temperature and concentrations. The concentration dependence is expressed in the form of a quadratic expression involving the volume fractions of the interacting species. The temperature dependence is expressed in the form .To obtain the temperature-dependent interaction parameters for organic molecule-water and electrolyte-water systems, Critical solution temperature of electrolyte -water-organic molecules is measured using cloud point measuring apparatus The temperature and composition dependent interaction parameters for electrolyte-water-organic molecule are estimated through measurement of cloud point of solution. The model is used to estimate critical solution temperature (CST) of electrolyte water-organic molecules solution. We have experimentally determined the critical solution temperature of different compositions of electrolyte-water-organic molecule solution and compared the results with the estimates based on our model. The two sets of values show good agreement. On the other hand when only osmotic coefficients are used for estimation of the free energy model, CST predicted using the resulting model show poor agreement with the experiments. Thus, the importance of the CST data in the estimation of parameters of the thermodynamic model is confirmed through this work.

Keywords: concentrated electrolytes, Debye-Hückel theory, interaction parameters, Robinson-Stokes-Glueckauf model, Flory-Huggins model, critical solution temperature

Procedia PDF Downloads 389
30348 Fluid-Structure Interaction Study of Fluid Flow past Marine Turbine Blade Designed by Using Blade Element Theory and Momentum Theory

Authors: Abu Afree Andalib, M. Mezbah Uddin, M. Rafiur Rahman, M. Abir Hossain, Rajia Sultana Kamol

Abstract:

This paper deals with the analysis of flow past the marine turbine blade which is designed by using the blade element theory and momentum theory for the purpose of using in the field of renewable energy. The designed blade is analyzed for various parameters using FSI module of Ansys. Computational Fluid Dynamics is used for the study of fluid flow past the blade and other fluidic phenomena such as lift, drag, pressure differentials, energy dissipation in water. Finite Element Analysis (FEA) module of Ansys was used to analyze the structural parameter such as stress and stress density, localization point, deflection, force propagation. Fine mesh is considered in every case for more accuracy in the result according to computational machine power. The relevance of design, search and optimization with respect to complex fluid flow and structural modeling is considered and analyzed. The relevancy of design and optimization with respect to complex fluid for minimum drag force using Ansys Adjoint Solver module is analyzed as well. The graphical comparison of the above-mentioned parameter using CFD and FEA and subsequently FSI technique is illustrated and found the significant conformity between both the results.

Keywords: blade element theory, computational fluid dynamics, finite element analysis, fluid-structure interaction, momentum theory

Procedia PDF Downloads 298
30347 First Step into a Smoke-Free Life: The Effectivity of Peer Education Programme of Midwifery Students

Authors: Rabia Genc, Aysun Eksioglu, Emine Serap Sarican, Sibel Icke

Abstract:

Today the habit of cigarette smoking is among one of the most important public health concerns because of the health problems it leads to. The most important and hazardous group to use tobacco and tobacco products is adolescents and teenagers. And one of the most effective ways to prevent them from starting to smoke is education. This research is a kind of educational intervention study which was carried out in order to evaluate the effect of peer education on the teenagers' knowledge about smoking. The research was carried out between October 15, 2013 and September 9, 2015 at Ege University Ataturk Vocational Health School. The population of the research comprised of the students that have been studying at Ege University Atatürk Vocational Health School, Midwifery Department (N=390). The peer educator group that would give training on smoking consisted of 10 people, and the peer groups that would be trained were divided into two groups via simple randomization as experimental group (n=185) and control group (n=185). Questionnaire, information evaluation form, and informed consent forms were used as date collection tools. The analysis of the data which were collected in the study was carried out on Statistical Package for Social Science (SPSS 15.0). It was found out that 62.5 % of the students who were in peer educator group had smoked in some period of their lives; however, none of them continued to smoke. When they were asked about their reasons to start smoking, 25% said they just wanted to try it, and 25% of them answered that it was because of their friend groups. When the pre-peer education and post-peer education point averages of peer educator group were evaluated, the results showed that there was a significant difference between the point averages (p < 0.05). When the cigarette use of experimental group and the control group were evaluated, it was clear that 18.2% of the experimental group and 24.2%of the control group still smokes. 9.1% of the experimental group and 14.8% of control group stated that they started smoking because of their friend groups. Among the students who smoke 15.9% of the ones who belongs to the experimental group and 21.9% of the ones who belong to the control group stated they are thinking of quitting smoking. It was clear that there is a significant difference between the pre-education and post-education point averages of experimental group statistically (p ≤ 0.05); however, in terms of control group, there were no significant differences between the pre-test post-test averages statistically. Between the pre-test post-test averages of experimental and control groups there were not any statistically significant differences (p > 0.05). It was found out in the study that the peer education programme is not effective on the smoking habit of Vocational Health School students. When the future studies are being planned in order to evaluate the peer education activity, it can be taken into consideration that the peer education takes a long term and the students in the educator group will be more enthusiastic and a kind of leader in their environment.

Keywords: midwifery, peer, peer education, smoking

Procedia PDF Downloads 219
30346 A New Type Safety-Door for Earthquake Disaster Prevention: Part I

Authors: Daniel Y. Abebe, Jaehyouk Choi

Abstract:

From the past earthquake events, many people get hurt at the exit while they are trying to go out of the buildings because of the exit doors are unable to be opened. The door is not opened because it deviates from its the original position. The aim of this research is to develop and evaluate a new type safety door that keeps the door frame in its original position or keeps its edge angles perpendicular during and post-earthquake. The proposed door is composed of three components: outer frame joined to the wall, inner frame (door frame) and circular hollow section connected to the inner and outer frame which is used as seismic energy dissipating device.

Keywords: safety-door, earthquake disaster, low yield point steel, passive energy dissipating device, FE analysis

Procedia PDF Downloads 520
30345 The Validity of a Literature Review Rubric in the Ecuadorian Context

Authors: Francisco Bolaños-Burgos, Antonio Cevallos Gamboa

Abstract:

The aim of this paper is to evaluate the validity of a literature review rubric in the Ecuadorian context at the graduate level. The sample was composed of 73 students of the online and on-site study format in the years 2015-2016. The instrument has 20 items (α=0.974) ranked in a 5-point Likert scale with six dimensions. The validity analysis was made by experts´ criterion. Findings evidenced that there is no significance difference between grades based on the study formats and that women write better than men. Furthermore, the students lacked to describe the limitation of their research and are good in writing: the research topic of the abstract, the conclusion in terms of the research objective and the citation norms (APA).

Keywords: literature review, rubric, validity, Ecuadorian context, graduate level

Procedia PDF Downloads 260
30344 Effects of Preparation Conditions on the Properties of Crumb Rubber Modified Binder

Authors: Baha Vural Kök, Mehmet Yilmaz, Mustafa Akpolat, Cihat Sav

Abstract:

Various types of additives are used frequently in order to improve the rheological and mechanical properties of bituminous mixtures. Small devices instead of full scale machines are used for bitumen modification in the laboratory. These laboratory scale devices vary in terms of their properties such as mixing rate, mixing blade and the amount of binder. In this study, the effect of mixing rate and time during the bitumen modification processes on conventional and rheological properties of pure and crumb rubber modified binder were investigated. Penetration, softening point, rotational viscosity (RV) and dynamic shear rheometer (DSR) tests were applied to pure and CR modified bitumen. It was concluded that the penetration and softening point test did not show the efficiency of CR obtained by different mixing conditions. Besides, oxidation that occurred during the preparation processes plays a great part in the improvement effects of the modified binder.

Keywords: bitumen, crumb rubber, modification, rheological properties

Procedia PDF Downloads 310