Search results for: BOP components
3041 Evaluation of the Energy Performance and Emissions of an Aircraft Engine: J69 Using Fuel Blends of Jet A1 and Biodiesel
Authors: Gabriel Fernando Talero Rojas, Vladimir Silva Leal, Camilo Bayona-Roa, Juan Pava, Mauricio Lopez Gomez
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The substitution of conventional aviation fuels with biomass-derived alternative fuels is an emerging field of study in the aviation transport, mainly due to its energy consumption, the contribution to the global Greenhouse Gas - GHG emissions and the fossil fuel price fluctuations. Nevertheless, several challenges remain as the biofuel production cost and its degradative effect over the fuel systems that alter the operating safety. Moreover, experimentation on full-scale aeronautic turbines are expensive and complex, leading to most of the research to the testing of small-size turbojets with a major absence of information regarding the effects in the energy performance and the emissions. The main purpose of the current study is to present the results of experimentation in a full-scale military turbojet engine J69-T-25A (presented in Fig. 1) with 640 kW of power rating and using blends of Jet A1 with oil palm biodiesel. The main findings are related to the thrust specific fuel consumption – TSFC, the engine global efficiency – η, the air/fuel ratio – AFR and the volume fractions of O2, CO2, CO, and HC. Two fuels are used in the present study: a commercial Jet A1 and a Colombian palm oil biodiesel. The experimental plan is conducted using the biodiesel volume contents - w_BD from 0 % (B0) to 50 % (B50). The engine operating regimes are set to Idle, Cruise, and Take-off conditions. The turbojet engine J69 is used by the Colombian Air Force and it is installed in a testing bench with the instrumentation that corresponds to the technical manual of the engine. The increment of w_BD from 0 % to 50 % reduces the η near 3,3 % and the thrust force in a 26,6 % at Idle regime. These variations are related to the reduction of the 〖HHV〗_ad of the fuel blend. The evolved CO and HC tend to be reduced in all the operating conditions when increasing w_BD. Furthermore, a reduction of the atomization angle is presented in Fig. 2, indicating a poor atomization in the fuel nozzle injectors when using a higher biodiesel content as the viscosity of fuel blend increases. An evolution of cloudiness is also observed during the shutdown procedure as presented in Fig. 3a, particularly after 20 % of biodiesel content in the fuel blend. This promotes the contamination of some components of the combustion chamber of the J69 engine with soot and unburned matter (Fig. 3). Thus, the substitution of biodiesel content above 20 % is not recommended in order to avoid a significant decrease of η and the thrust force. A more detail examination of the mechanical wearing of the main components of the engine is advised in further studies.Keywords: aviation, air to fuel ratio, biodiesel, energy performance, fuel atomization, gas turbine
Procedia PDF Downloads 1093040 Challenges in Anti-Counterfeiting of Cyber-Physical Systems
Authors: Daniel Kliewe, Arno Kühn, Roman Dumitrescu, Jürgen Gausemeier
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This paper examines the system protection for cyber-physical systems (CPS). CPS are particularly characterized by their networking system components. This means they are able to adapt to the needs of their users and its environment. With this ability, CPS have new, specific requirements on the protection against anti-counterfeiting, know-how loss and manipulation. They increase the requirements on system protection because piracy attacks can be more diverse, for example because of an increasing number of interfaces or through the networking abilities. The new requirements were identified and in a next step matched with existing protective measures. Due to the found gap the development of new protection measures has to be forced to close this gap. Moreover a comparison of the effectiveness between selected measures was realized and the first results are presented in the paper.Keywords: anti-counterfeiting, cyber physical systems, intellectual property (IP), knowledge management, system protection
Procedia PDF Downloads 4963039 Culture Medium Design Based on Whey for the Growth and Bacteriocin Production of Strains of Pediococcus pentosaceus
Authors: Carolina Gutierrez-Cortes, Hector Suarez, Gustavo Buitrago
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Bacteriocins are antimicrobial peptides produced by bacteria as a competitive strategy for substrate and habitat. Those peptides have a potential use as food biopreservatives due to their antimicrobial activity against foodborne pathogens, avoiding the use of additives that can be harmful to consumers. The industrial production of bacteriocins is currently expensive; one of the options to be competitive is the development of economic culture media, for example, with the use of agro-industrial wastes such as whey. This study evaluated the growth and production of bacteriocins from four strains: Pediococcus pentosaceus 63, Pediococcus pentosaceus 145, Pediococcus pentosaceus 146 and Pediococcus pentosaceus 147 isolated from ‘minas cheese’ (artisanal cheese made from raw milk in the state of Minas Gerais, Brazil) in order to select a strain with growth at high rates and higher antimicrobial activity against Listeria monocytogenes 104 after incubation on the culture medium designed with whey and other components. The media used were: MRS broth, modified MRS broth (using different sources of carbon and nitrogen and different amounts of micronutrients) and a culture medium designed by a factorial design using whey and other components. The final biomass concentrations of the four strains in MRS broth after 24 hours of incubation were very similar 9.25, 9.33, 9.25 and 9.22 (log CFU/mL) for P. pentosaceus 63, P. pentosaceus 145, P. pentosaceus 146 and P. pentosaceus 147 respectively. In the same assays, antimicrobial activity of 3200 AU/mL for the first three and of 12800 AU/mL for P. pentosaceus 147 were obtained. Culture of P. pentosaceus 63 on modified MRS broth, showed the effect of some sources of carbon on the activity of bacteriocin, obtaining 12800 AU/mL with dextrose and 25600 AU/mL with maltose. Cultures of P. pentosaceus 145, 146 and 147 with these same sugars presented activity of 12800 AU/mL. It was observed that the modified MRS medium using whey increased the antimicrobial activity of the strains at 16000, 6400, 16000 and 19200 AU/mL for each strain respectively, keeping the biomass at values close to 9 log units. About nitrogen sources, it was observed that the combination of peptone (10 g /L), meat extract (10 g/L) and yeast extract (5 g/L) promoted the highest activity (12800 AU/mL), and in all cases MgSO4, MnSO4, K2HPO4 and ammonium citrate at low concentrations adversely affected bacteriocin production. Because P. pentosaceus 147 showed the highest antimicrobial activity in the presence of whey, it was used to evaluate the culture medium (peptone (10 g/L), meat extract (8 g/L), yeast extract (2 g/L), Tween® 80 (1 g/L), ammonium citrate (2 g/L), sodium acetate (5 g/L), MgSO4 (0.2 g/L), MnSO4 (0.04 g/L)). With the designed medium added with whey, 9.34 log units of biomass concentration and 19200 AU/mL were achieved for P. pentosaceus 147. The above suggest that the new medium promotes the antimicrobial activity of P. pentosaceus 147 allowing the use of an economic medium using whey.Keywords: antimicrobial activity, bacteriocins, pediococcus, whey
Procedia PDF Downloads 2253038 Aligning Organizational Culture and Compensation Strategies
Authors: Giuseppe Maria Russo, Patrícia Amélia Tomei, Antônio Linhares, André Moreira Santos
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Alignment between management strategies, policies and practices with organizational cultures holds great potential to meet the challenges of retaining professionals and maintaining their commitment. In this article, authors consider that when it is aligned with company strategy, compensation acts as an incentive for developing common visions within the organizational culture. This article verified the correlation between types of culture and compensation’s strategic components and provided inputs for the definition of strategies aligned with cultural typologies. We conclude that the impact of compensation variables varies according to the type of organizational culture. This result reinforces the theory that different cultures define different organizational strategies. Thus, compensation strategies may explain types of organizational culture.Keywords: compensation, Handy’s cultural typology, organizational culture, rewards
Procedia PDF Downloads 6593037 Detect QOS Attacks Using Machine Learning Algorithm
Authors: Christodoulou Christos, Politis Anastasios
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A large majority of users favoured to wireless LAN connection since it was so simple to use. A wireless network can be the target of numerous attacks. Class hijacking is a well-known attack that is fairly simple to execute and has significant repercussions on users. The statistical flow analysis based on machine learning (ML) techniques is a promising categorization methodology. In a given dataset, which in the context of this paper is a collection of components representing frames belonging to various flows, machine learning (ML) can offer a technique for identifying and characterizing structural patterns. It is possible to classify individual packets using these patterns. It is possible to identify fraudulent conduct, such as class hijacking, and take necessary action as a result. In this study, we explore a way to use machine learning approaches to thwart this attack.Keywords: wireless lan, quality of service, machine learning, class hijacking, EDCA remapping
Procedia PDF Downloads 573036 Modeling a Closed Loop Supply Chain with Continuous Price Decrease and Dynamic Deterministic Demand
Authors: H. R. Kamali, A. Sadegheih, M. A. Vahdat-Zad, H. Khademi-Zare
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In this paper, a single product, multi-echelon, multi-period closed loop supply chain is surveyed, including a variety of costs, time conditions, and capacities, to plan and determine the values and time of the components procurement, production, distribution, recycling and disposal specially for high-tech products that undergo a decreasing production cost and sale price over time. For this purpose, the mathematic model of the problem that is a kind of mixed integer linear programming is presented, and it is finally proved that the problem belongs to the category of NP-hard problems.Keywords: closed loop supply chain, continuous price decrease, NP-hard, planning
Procedia PDF Downloads 3623035 Graphene Materials for Efficient Hybrid Solar Cells: A Spectroscopic Investigation
Authors: Mohammed Khenfouch, Fokotsa V. Molefe, Bakang M. Mothudi
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Nowadays, graphene and its composites are universally known as promising materials. They show their potential in a large field of applications including photovoltaics. This study reports on the role of nanohybrids and nanosystems known as strong light harvesters in the efficiency of graphene hybrid solar cells. Our system included Graphene/ZnO/Porphyrin/P3HT layers. Moreover, the physical properties including surface/interface, optical and vibrational properties were also studied. Our investigations confirmed the interaction between the different components as well as the sensitivity of their photonics to the synthesis conditions. Remarkable energy and charge transfer were detected and deeply investigated. Hence, the optimization of the conditions will lead to the fabrication of higher conversion efficiency in graphene solar cells.Keywords: graphene, optoelectronics, nanohybrids, solar cells
Procedia PDF Downloads 1663034 Improved Pattern Matching Applied to Surface Mounting Devices Components Localization on Automated Optical Inspection
Authors: Pedro M. A. Vitoriano, Tito. G. Amaral
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Automated Optical Inspection (AOI) Systems are commonly used on Printed Circuit Boards (PCB) manufacturing. The use of this technology has been proven as highly efficient for process improvements and quality achievements. The correct extraction of the component for posterior analysis is a critical step of the AOI process. Nowadays, the Pattern Matching Algorithm is commonly used, although this algorithm requires extensive calculations and is time consuming. This paper will present an improved algorithm for the component localization process, with the capability of implementation in a parallel execution system.Keywords: AOI, automated optical inspection, SMD, surface mounting devices, pattern matching, parallel execution
Procedia PDF Downloads 2983033 Investigation on the Acoustical Transmission Path of Additive Printed Metals
Authors: Raphael Rehmet, Armin Lohrengel, Prof Dr-Ing
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In terms of making machines more silent and convenient, it is necessary to analyze the transmission path of mechanical vibrations and structure-bone noise. A typical solution for the elimination of structure-bone noise would be to simply add stiffeners or additional masses to change the transmission behavior and, thereby, avoid the propagation of vibrations. Another solution could be to use materials with a different damping behavior, such as elastomers, to isolate the machine dynamically. This research approach investigates the damping behavior of additive printed components made from structural steel or titanium, which have been manufactured in the “Laser Powder Bed Fusion“-process. By using the design flexibility which this process comes with, it will be investigated how a local impedance difference will affect the transmission behavior of the specimens.Keywords: 3D-printed, acoustics, dynamics, impedance
Procedia PDF Downloads 2053032 Prediction of Marine Ecosystem Changes Based on the Integrated Analysis of Multivariate Data Sets
Authors: Prozorkevitch D., Mishurov A., Sokolov K., Karsakov L., Pestrikova L.
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The current body of knowledge about the marine environment and the dynamics of marine ecosystems includes a huge amount of heterogeneous data collected over decades. It generally includes a wide range of hydrological, biological and fishery data. Marine researchers collect these data and analyze how and why the ecosystem changes from past to present. Based on these historical records and linkages between the processes it is possible to predict future changes. Multivariate analysis of trends and their interconnection in the marine ecosystem may be used as an instrument for predicting further ecosystem evolution. A wide range of information about the components of the marine ecosystem for more than 50 years needs to be used to investigate how these arrays can help to predict the future.Keywords: barents sea ecosystem, abiotic, biotic, data sets, trends, prediction
Procedia PDF Downloads 1143031 Analysis of Causality between Defect Causes Using Association Rule Mining
Authors: Sangdeok Lee, Sangwon Han, Changtaek Hyun
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Construction defects are major components that result in negative impacts on project performance including schedule delays and cost overruns. Since construction defects generally occur when a few associated causes combine, a thorough understanding of defect causality is required in order to more systematically prevent construction defects. To address this issue, this paper uses association rule mining (ARM) to quantify the causality between defect causes, and social network analysis (SNA) to find indirect causality among them. The suggested approach is validated with 350 defect instances from concrete works in 32 projects in Korea. The results show that the interrelationships revealed by the approach reflect the characteristics of the concrete task and the important causes that should be prevented.Keywords: causality, defect causes, social network analysis, association rule mining
Procedia PDF Downloads 3653030 Deformation and Energy Absorption of Corrugated Tubes
Authors: Mohammad R. Rahim, Shagil Akhtar, Prem K. Bharti, Syed Muneeb Iqbal
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Deformation and energy absorption studies with corrugated tubes where corrugation is perpendicular to the line of action which coincides exactly with the unstrained axis of the tubes. In the present study, several specimens with various geometric parameters are prepared and compressed quasi-statistically in ANSYS Workbench. It is observed that tubes with perpendicular corrugation alters the deformation condition considerably and culminates in a substantial escalation in energy absorption scope in juxtaposed with the tubes having a circular cross-section. This study will help automotive, aerospace and various other industries to design superior components with perpendicular corrugated tubes and will reduce the experimental trials by conducting the numerical simulations.Keywords: ANSYS Workbench, deformation and energy absorption, corrugated tubes, quasi-static compression
Procedia PDF Downloads 3843029 Anomaly: A Case of Babri Masjid Dispute
Authors: Karitikeya Sonker
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Religion as a discrete system through its lawful internal working produces an output in the form of realised spatial order with its social logic and a social order with its spatial logic. Thus, it appears to exhibit its duality of spatial and trans-spatial. The components of this system share a relevance forming a collective. This shared relevance creates meaning forming a group where all collectives share one identity. This group with its new social order and its spatial logic revive the already existing spatial order. These religious groups do so having a tendency to expand resulting in the production of space in a situation of encounter where they have found relevance. But an encounter without a lawful internal working of a discrete system results in anomaly because groups do not find relevance due to the absence of collective identity. Events happen all around. One of the main reasons we could say that something became an event is because of conflict. Conflict not in its definitive sense but any occurrence that happens because of an intervention that creates an event worth remembering. The unfolding of such events creates Cities and Urban spaces which exhibit their duality of spatial and trans-spatial by behaving as a discrete system. This system through its lawful internal working produces an output in the form of realized spatial order with its social logic and a social order with spatial logic. The components of this system form a collective through a shared a relevance. This shared relevance creates meaning forming a group where all collectives share one identity. This group with its new social order and its spatial logic revives the already existing spatial order. These groups do so having a tendency to expand resulting in the production of space in a situation of encounter where they have found relevance. But an encounter without a lawful internal working of the discrete system results in anomaly because groups do not find relevance due to the absence of collective identity. This paper makes an effort to explore one such even in the case of Babri Mosque and Ramjanmabhumi, Ayodhya to explain the anomaly as transposition of social and spatial. The paper through the case studies makes an attempt to generate an equation explaining the two different situations of religious encounters, former reviving the social and spatial order and the other resulting in anomaly. Through the case study, it makes an attempt to generate an equation explaining the two different situations of religious encounters, former reviving the social and spatial order and the other resulting in anomaly.Keywords: Babri Masjid, Ayodhya, conflict, religion
Procedia PDF Downloads 2743028 High Throughput LC-MS/MS Studies on Sperm Proteome of Malnad Gidda (Bos Indicus) Cattle
Authors: Kerekoppa Puttaiah Bhatta Ramesha, Uday Kannegundla, Praseeda Mol, Lathika Gopalakrishnan, Jagish Kour Reen, Gourav Dey, Manish Kumar, Sakthivel Jeyakumar, Arumugam Kumaresan, Kiran Kumar M., Thottethodi Subrahmanya Keshava Prasad
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Spermatozoa are the highly specialized transcriptionally and translationally inactive haploid male gamete. The understanding of proteome of sperm is indispensable to explore the mechanism of sperm motility and fertility. Though there is a large number of human sperm proteomic studies, in-depth proteomic information on Bos indicus spermatozoa is not well established yet. Therefore, we illustrated the profile of sperm proteome in indigenous cattle, Malnad gidda (Bos Indicus), using high-resolution mass spectrometry. In the current study, two semen ejaculates from 3 breeding bulls were collected employing the artificial vaginal method. Using 45% percoll purification, spermatozoa cells were isolated. Protein was extracted using lysis buffer containing 2% Sodium Dodecyl Sulphate (SDS) and protein concentration was estimated. Fifty micrograms of protein from each individual were pooled for further downstream processing. Pooled sample was fractionated using SDS-Poly Acrylamide Gel Electrophoresis, which is followed by in-gel digestion. The peptides were subjected to C18 Stage Tip clean-up and analyzed in Orbitrap Fusion Tribrid mass spectrometer interfaced with Proxeon Easy-nano LC II system (Thermo Scientific, Bremen, Germany). We identified a total of 6773 peptides with 28426 peptide spectral matches, which belonged to 1081 proteins. Gene ontology analysis has been carried out to determine the biological processes, molecular functions and cellular components associated with sperm protein. The biological process chiefly represented our data is an oxidation-reduction process (5%), spermatogenesis (2.5%) and spermatid development (1.4%). The highlighted molecular functions are ATP, and GTP binding (14%) and the prominent cellular components most observed in our data were nuclear membrane (1.5%), acrosomal vesicle (1.4%), and motile cilium (1.3%). Seventeen percent of sperm proteins identified in this study were involved in metabolic pathways. To the best of our knowledge, this data represents the first total sperm proteome from indigenous cattle, Malnad Gidda. We believe that our preliminary findings could provide a strong base for the future understanding of bovine sperm proteomics.Keywords: Bos indicus, Malnad Gidda, mass spectrometry, spermatozoa
Procedia PDF Downloads 1953027 Speckle Noise Reduction Using Anisotropic Filter Based on Wavelets
Authors: Kritika Bansal, Akwinder Kaur, Shruti Gujral
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In this paper, the approach of denoising is solved by using a new hybrid technique which associates the different denoising methods. Wavelet thresholding and anisotropic diffusion filter are the two different filters in our hybrid techniques. The Wavelet thresholding removes the noise by removing the high frequency components with lesser edge preservation, whereas an anisotropic diffusion filters is based on partial differential equation, (PDE) to remove the speckle noise. This PDE approach is used to preserve the edges and provides better smoothing. So our new method proposes a combination of these two filtering methods which performs better results in terms of peak signal to noise ratio (PSNR), coefficient of correlation (COC) and equivalent no of looks (ENL).Keywords: denoising, anisotropic diffusion filter, multiplicative noise, speckle, wavelets
Procedia PDF Downloads 5103026 Nazik Al-Malaika and Nostalgic approach
Authors: sulmaz Mozaffari
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Nostalgia is one of the hot-debated issues in critical psychology which has been translated as the yearning or gloom in Persian. It is defined as the regret of the sweet past and the contrast of the present with the past. The feeling of alienation and being remote from the home, remembering death, the regret of childhood and youth, separation of the beloved, remembering the glorious era of history, desire for the ancient times, and the hope for Utopia are considered as its components. Nazik Al-Malaika, a contemporary poet of Arabic literature, has depicted some shapes and dimensions of sympathy, regret and anguish in her poems. Utilizing a nostalgic approach to the past, this paper has reflected upon love, memories of childhood and youth and hope for Utopia "and also aimed at explaining each one's manifestations through a comparative perspective.Keywords: Nazik al-malaika, poem, nostalgia, personal memory, collective memory
Procedia PDF Downloads 4083025 Study on Residual Stress Measurement of Inconel-718 under Different Lubricating Conditions
Authors: M. Sandeep Kumar, Vasu Velagapudi, A. Venugopal
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When machining is carried out on a workpiece, residual stresses are induced in the workpiece due to nonuniform thermal and mechanical loads. These stresses play a vital role in the surface integrity of the final product or the output. Inconel 718 is commonly used in critical structural components of aircraft engines due to its properties at high temperatures. Therefore it is important to keep down the stresses induced due to machining. This can be achieved through proper lubricating conditions. In this work, experiments were carried out to check the influence of the developed nanofluid as cutting fluids on residual stresses developed during the course of machining. The results of MQL/Nanofluids were compared with MQL/Vegetable oil and dry machining lubricating condition. Results indicate the reduction in residual stress with the use of MQL/Nanofluid.Keywords: nanofluids, MQL, residual stress, Inconel-718
Procedia PDF Downloads 2573024 Measuring Science and Technology Innovation Capacity in Developing Countries: From a National Innovation System
Authors: Haeng A. Seo, Changseok Oh, Seung Jun Yoo
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This study attempts to examine the disparities in S&T innovation capacity from 14 developing countries to discuss how to support specific features in national innovation systems. It includes East-Asian, Middle-Asian, Central American and African countries. Here, we particularly focus on five dimensions- resources, activities, network, environment and performance- with 37 indicators. They were derived as structuring components of the relevant diagnostic model, which encompasses the whole process of S&T innovation from the input of resources to the output of economically valuable results. For many developing nations, economic industries remain weaker than actual S&T capabilities, and relevant regulatory authorities may not exist. This paper will be helpful to provide basic evidence and to set directions for better national S&T Innovation capacities and toward national competitiveness.Keywords: developing countries, measurement, NIS, S&T innovation capacity
Procedia PDF Downloads 2813023 The Effects of Dietary Flaxseed Oil Supplementations on Punicic Acid of the Yolks in Quail Muscle
Authors: Ozcan Baris Citil
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This experiment was carried out to determine effects of Japanese quail diets which is supplemented with different levels of punicic acids and CLA compositions in Japanese quail. In this study, eighty laying quails at 12 weeks of age were used. They were divided into 4 tretament groups, each group included 20 quails. The diets in treatment groups contained different levels of flaxseed oil. At the end of the experiment lasted for 21 days, 5 quail taken from each group were subjected to analysis. Punicic acid content of muscle were determined by gas chromatography. Twenty five different fatty acid components were determinated in the compositions of quail muscle. No differences were found in oil content among the groups.Keywords: quail egg yolk, punicic acid, flaxseed oil, gas chromatography
Procedia PDF Downloads 2913022 A Performance Analysis of Different Scheduling Schemes in WiMAX
Authors: A. Youseef
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One of the most aims of IEEE 802.16 (WiMAX) is to present high-speed wireless access to cover wide range coverage. The base station (BS) and the subscriber station (SS) are the main parts of WiMAX. WiMAX uses either Point-to-Multipoint (PMP) or mesh topologies. In the PMP mode, the SSs connect to the BS to gain access to the network. However, in the mesh mode, the SSs connect to each other to gain access to the BS. The main components of QoS management in the 802.16 standard are the admission control, buffer management, and packet scheduling. There are several researches proposed to create an efficient packet scheduling schemes. Therefore, we use QualNet 5.0.2 to study the performance of different scheduling schemes, such as WFQ, SCFQ, RR, and SP when the numbers of SSs increase. We find that when the number of SSs increases, the average jitter and average end-to-end delay is increased and the throughput is reduced.Keywords: WiMAX, scheduling scheme, QoS, QualNet
Procedia PDF Downloads 4543021 3D-Printing of Waveguide Terminations: Effect of Material Shape and Structuring on Their Characteristics
Authors: Lana Damaj, Vincent Laur, Azar Maalouf, Alexis Chevalier
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Matched termination is an important part of the passive waveguide components. It is typically used at the end of a waveguide transmission line to prevent reflections and improve signal quality. Waveguide terminations (loads) are commonly used in microwave and RF applications. In traditional microwave architectures, usually, waveguide termination consists of a standard rectangular waveguide made by a lossy resistive material, and ended by shorting metallic plate. These types of terminations are used, to dissipate the energy as heat. However, these terminations may increase the size and the weight of the overall system. New alternative solution consists in developing terminations based on 3D-printing of materials. Designing such terminations is very challenging since it should meet the requirements imposed by the system. These requirements include many parameters such as the absorption, the power handling capability in addition to the cost, the size and the weight that have to be minimized. 3D-printing is a shaping process that enables the production of complex geometries. It allows to find best compromise between requirements. In this paper, a comparison study has been made between different existing and new shapes of waveguide terminations. Indeed, 3D printing of absorbers makes it possible to study not only standard shapes (wedge, pyramid, tongue) but also more complex topologies such as exponential ones. These shapes have been designed and simulated using CST MWS®. The loads have been printed using the carbon-filled PolyLactic Acid, conductive PLA from ProtoPasta. Since the terminations has been characterized in the X-band (from 8GHz to 12GHz), the rectangular waveguide standard WR-90 has been selected. The classical wedge shape has been used as a reference. First, all loads have been simulated with the same length and two parameters have been compared: the absorption level (level of |S11|) and the dissipated power density. This study shows that the concave exponential pyramidal shape has the better absorption level and the convex exponential pyramidal shape has the better dissipated power density level. These two loads have been printed in order to measure their properties. A good agreement between the simulated and measured reflection coefficient has been obtained. Furthermore, a study of material structuring based on the honeycomb hexagonal structure has been investigated in order to vary the effective properties. In the final paper, the detailed methodology and the simulated and measured results will be presented in order to show how 3D-printing can allow controlling mass, weight, absorption level and power behaviour.Keywords: additive manufacturing, electromagnetic composite materials, microwave measurements, passive components, power handling capacity (PHC), 3D-printing
Procedia PDF Downloads 193020 The Impact of Grammatical Differences on English-Mandarin Chinese Simultaneous Interpreting
Authors: Miao Sabrina Wang
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This paper examines the impact of grammatical differences on simultaneous interpreting from English into Mandarin Chinese by drawing upon an empirical study of professional and student interpreters. The research focuses on the effects of three grammatical categories including passives, adverbial components and noun phrases on simultaneous interpreting. For each category, interpretations of instances in which the grammatical structures are the same across the two languages are compared with interpretations of instances in which the grammatical structures differ across the two languages in terms of content accuracy and delivery appropriateness. The results indicate that grammatical differences have a significant impact on the interpreting performance of both professionals and students.Keywords: content accuracy, delivery appropriateness, grammatical differences, simultaneous interpreting
Procedia PDF Downloads 5393019 Lead Free BNT-BKT-BMgT-CoFe₂O₄ Magnetoelectric Nanoparticulate Composite Thin Films Prepared by Chemical Solution Deposition Method
Authors: A. K. Paul, Vinod Kumar
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Lead free magnetoelectric (ME) nanoparticulate (1−x) BNT-BKT-BMgT−x CFO (x = 0, 0.1, 0.2, 0.3) composite films were synthesized using chemical solution deposition method. The X-ray diffraction and transmission electron microscope (TEM) reveal that CFO nanoparticles were well distributed in the matrix of BNT-BKT-BMgT. The nanocomposite films exhibit both good magnetic and ferroelectric properties at room temperature (R-T). It is concluded that the modulation in compositions of piezomagnetic/piezoelectric components plays a fundamental role in the magnetoelectric coupling in these nanoparticulate composite films. These ME composites provide a great opportunity as potential lead-free systems for ME devices.Keywords: lead free multiferroic, nanocomposite, ferroelectric, ferromagnetic and magneto-electric properties
Procedia PDF Downloads 1263018 Single-Crystal Kerfless 2D Array Transducer for Volumetric Medical Imaging: Theoretical Study
Authors: Jurij Tasinkiewicz
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The aim of this work is to present a theoretical analysis of a 2D ultrasound transducer comprised of crossed arrays of metal strips placed on both sides of thin piezoelectric layer (a). Such a structure is capable of electronic beam-steering of generated wave beam both in elevation and azimuth. In this paper, a semi-analytical model of the considered transducer is developed. It is based on generalization of the well-known BIS-expansion method. Specifically, applying the electrostatic approximation, the electric field components on the surface of the layer are expanded into fast converging series of double periodic spatial harmonics with corresponding amplitudes represented by the properly chosen Legendre polynomials. The problem is reduced to numerical solving of certain system of linear equations for unknown expansion coefficients.Keywords: beamforming, transducer array, BIS-expansion, piezoelectric layer
Procedia PDF Downloads 4223017 Application of the Material Point Method as a New Fast Simulation Technique for Textile Composites Forming and Material Handling
Authors: Amir Nazemi, Milad Ramezankhani, Marian Kӧrber, Abbas S. Milani
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The excellent strength to weight ratio of woven fabric composites, along with their high formability, is one of the primary design parameters defining their increased use in modern manufacturing processes, including those in aerospace and automotive. However, for emerging automated preform processes under the smart manufacturing paradigm, complex geometries of finished components continue to bring several challenges to the designers to cope with manufacturing defects on site. Wrinklinge. g. is a common defectoccurring during the forming process and handling of semi-finished textile composites. One of the main reasons for this defect is the weak bending stiffness of fibers in unconsolidated state, causing excessive relative motion between them. Further challenges are represented by the automated handling of large-area fiber blanks with specialized gripper systems. For fabric composites forming simulations, the finite element (FE)method is a longstanding tool usedfor prediction and mitigation of manufacturing defects. Such simulations are predominately meant, not only to predict the onset, growth, and shape of wrinkles but also to determine the best processing condition that can yield optimized positioning of the fibers upon forming (or robot handling in the automated processes case). However, the need for use of small-time steps via explicit FE codes, facing numerical instabilities, as well as large computational time, are among notable drawbacks of the current FEtools, hindering their extensive use as fast and yet efficient digital twins in industry. This paper presents a novel woven fabric simulation technique through the application of the material point method (MPM), which enables the use of much larger time steps, facing less numerical instabilities, hence the ability to run significantly faster and efficient simulationsfor fabric materials handling and forming processes. Therefore, this method has the ability to enhance the development of automated fiber handling and preform processes by calculating the physical interactions with the MPM fiber models and rigid tool components. This enables the designers to virtually develop, test, and optimize their processes based on either algorithmicor Machine Learning applications. As a preliminary case study, forming of a hemispherical plain weave is shown, and the results are compared to theFE simulations, as well as experiments.Keywords: material point method, woven fabric composites, forming, material handling
Procedia PDF Downloads 1803016 How to Talk about It without Talking about It: Cognitive Processing Therapy Offers Trauma Symptom Relief without Violating Cultural Norms
Authors: Anne Giles
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Humans naturally wish they could forget traumatic experiences. To help prevent future harm, however, the human brain has evolved to retain data about experiences of threat, alarm, or violation. When given compassionate support and assistance with thinking helpfully and realistically about traumatic events, most people can adjust to experiencing hardships, albeit with residual sad, unfortunate memories. Persistent, recurrent, intrusive memories, difficulty sleeping, emotion dysregulation, and avoidance of reminders, however, may be symptoms of Post-traumatic Stress Disorder (PTSD). Brain scans show that PTSD affects brain functioning. We currently have no physical means of restoring the system of brain structures and functions involved with PTSD. Medications may ease some symptoms but not others. However, forms of "talk therapy" with cognitive components have been found by researchers to reduce, even resolve, a broad spectrum of trauma symptoms. Many cultures have taboos against talking about hardships. Individuals may present themselves to mental health care professionals with severe, disabling trauma symptoms but, because of cultural norms, be unable to speak about them. In China, for example, relationship expectations may include the belief, "Bad things happening in the family should stay in the family (jiāchǒu bùkě wàiyán 家丑不可外扬)." The concept of "family (jiā 家)" may include partnerships, close and extended families, communities, companies, and the nation itself. In contrast to many trauma therapies, Cognitive Processing Therapy (CPT) for Post-traumatic Stress Disorder asks its participants to focus not on "what" happened but on "why" they think the trauma(s) occurred. The question "why" activates and exercises cognitive functioning. Brain scans of individuals with PTSD reveal executive functioning portions of the brain inadequately active, with emotion centers overly active. CPT conceptualizes PTSD as a network of cognitive distortions that keep an individual "stuck" in this under-functioning and over-functioning dynamic. Through asking participants forms of the question "why," plus offering a protocol for examining answers and relinquishing unhelpful beliefs, CPT assists individuals in consciously reactivating the cognitive, executive functions of their brains, thus restoring normal functioning and reducing distressing trauma symptoms. The culturally sensitive components of CPT that allow people to "talk about it without talking about it" may offer the possibility for worldwide relief from symptoms of trauma.Keywords: cognitive processing therapy (CPT), cultural norms, post-traumatic stress disorder (PTSD), trauma recovery
Procedia PDF Downloads 2123015 Demystifying the Legitimacy of the International Court of Justice
Authors: Roger-Claude Liwanga
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Over the last seven decades, there has been a proliferation of international tribunals. Yet, they have not received unanimous approval, raising a question about their legitimacy. A legitimate international tribunal is one whose authority to adjudicate international disputes is perceived as justified. Using the case study of the International Court of Justice (ICJ), this article highlights the three criteria that should be considered in assessing the legitimacy of an international tribunal, which include legal, sociological, and moral elements. It also contends that the ICJ cannot claim 'full' legitimacy if any of these components of legitimacy is missing in its decisions. The article further suggests that the legitimacy of the ICJ has a dynamic nature, as litigating parties may constantly change their perception of the court’s authority at any time before, during, or after the judicial process. The article equally describes other factors that can contribute to maintaining the international court’s legitimacy, including fairness and unbiasedness, sound interpretation of international legal norms, and transparency.Keywords: international tribunals, legitimacy, human rights, international law
Procedia PDF Downloads 3763014 Freeze-Thaw Resistance of Concretes with BFSA
Authors: Alena Sicakova
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Air-cooled Blast furnace slag aggregate (BFSA) is usually referred to as a material providing for unique properties of concrete. On the other hand, negative influences are also presented in many aspects. The freeze-thaw resistance of concrete is dependent on many factors, including regional specifics and when a concrete mix is specified it is still difficult to tell its exact freeze-thaw resistance due to the different components affecting it. An important consideration in working with BFSA is the granularity and whether slag is sorted or not. The experimental part of the article represents a comparative testing of concrete using both the sorted and unsorted BFSA through the freeze-thaw resistance as an indicator of durability. Unsorted BFSA is able to be successfully used for concretes as they are specified for exposure class XF4 with providing that the type of cement is precisely selected.Keywords: blast furnace slag aggregate, concrete, freeze-thaw resistance
Procedia PDF Downloads 3953013 Grassland Development on Evacuated Sites for Wildlife Conservation in Satpura Tiger Reserve, India
Authors: Anjana Rajput, Sandeep Chouksey, Bhaskar Bhandari, Shimpi Chourasia
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Ecologically, grassland is any plant community dominated by grasses, whether they exist naturally or because of management practices. Most forest grasslands are anthropogenic and established plant communities planted for forage production, though some are established for soil and water conservation and wildlife habitat. In Satpura Tiger Reserve, Madhya Pradesh, India, most of the grasslands have been established on evacuated village sites. Total of 42 villages evacuated, and study was carried out in 23 sites to evaluate habitat improvement. Grasslands were classified into three categories, i.e., evacuated sites, established sites, and controlled sites. During the present study impact of various management interventions on grassland health was assessed. Grasslands assessment was done for its composition, status of palatable and non-palatable grasses, the status of herbs and legumes, status of weeds species, and carrying capacity of particular grassland. Presence of wild herbivore species in the grasslands with their abundance, availability of water resources was also assessed. Grassland productivity is dependent mainly on the biotic and abiotic components of the area, but management interventions may also play an important role in grassland composition and productivity. Variation in the status of palatable and non-palatable grasses, legumes, and weeds was recorded and found effected by management intervention practices. Overall in all the studied grasslands, the most dominant grasses recorded are Themeda quadrivalvis, Dichanthium annulatum, Ischaemum indicum, Oplismenus burmanii, Setaria pumilla, Cynodon dactylon, Heteropogon contortus, and Eragrostis tenella. Presence of wild herbivores, i.e., Chital, Sambar, Bison, Bluebull, Chinkara, Barking deer in the grassland area has been recorded through the installation of camera traps and estimated their abundance. Assessment of developed grasslands was done in terms of habitat suitability for Chital (Axis axis) and Sambar (Rusa unicolor). The parameters considered for suitability modeling are biotic and abiotic life requisite components existing in the area, i.e., density of grasses, density of legumes, availability of water, site elevation, site distance from human habitation. Findings of the present study would be useful for further grassland management and animal translocation programmes.Keywords: carrying capacity, dominant grasses, grassland, habitat suitability, management intervention, wild herbivore
Procedia PDF Downloads 1263012 Thermal Network Model for a Large Scale AC Induction Motor
Authors: Sushil Kumar, M. Dakshina Murty
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Thermal network modelling has proven to be important tool for thermal analysis of electrical machine. This article investigates numerical thermal network model and experimental performance of a large-scale AC motor. Experimental temperatures were measured using RTD in the stator which have been compared with the numerical data. Thermal network modelling fairly predicts the temperature of various components inside the large-scale AC motor. Results of stator winding temperature is compared with experimental results which are in close agreement with accuracy of 6-10%. This method of predicting hot spots within AC motors can be readily used by the motor designers for estimating the thermal hot spots of the machine.Keywords: AC motor, thermal network, heat transfer, modelling
Procedia PDF Downloads 324