Search results for: advantages and disadvantages
Commenced in January 2007
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Edition: International
Paper Count: 2286

Search results for: advantages and disadvantages

756 A Visual Analytics Tool for the Structural Health Monitoring of an Aircraft Panel

Authors: F. M. Pisano, M. Ciminello

Abstract:

Aerospace, mechanical, and civil engineering infrastructures can take advantages from damage detection and identification strategies in terms of maintenance cost reduction and operational life improvements, as well for safety scopes. The challenge is to detect so called “barely visible impact damage” (BVID), due to low/medium energy impacts, that can progressively compromise the structure integrity. The occurrence of any local change in material properties, that can degrade the structure performance, is to be monitored using so called Structural Health Monitoring (SHM) systems, in charge of comparing the structure states before and after damage occurs. SHM seeks for any "anomalous" response collected by means of sensor networks and then analyzed using appropriate algorithms. Independently of the specific analysis approach adopted for structural damage detection and localization, textual reports, tables and graphs describing possible outlier coordinates and damage severity are usually provided as artifacts to be elaborated for information extraction about the current health conditions of the structure under investigation. Visual Analytics can support the processing of monitored measurements offering data navigation and exploration tools leveraging the native human capabilities of understanding images faster than texts and tables. Herein, a SHM system enrichment by integration of a Visual Analytics component is investigated. Analytical dashboards have been created by combining worksheets, so that a useful Visual Analytics tool is provided to structural analysts for exploring the structure health conditions examined by a Principal Component Analysis based algorithm.

Keywords: interactive dashboards, optical fibers, structural health monitoring, visual analytics

Procedia PDF Downloads 101
755 Reusability of Coimmobilized Enzymes

Authors: Aleksandra Łochowicz, Daria Świętochowska, Loredano Pollegioni, Nazim Ocal, Franck Charmantray, Laurence Hecquet, Katarzyna Szymańska

Abstract:

Multienzymatic cascade reactions are nowadays widely used in pharmaceutical, chemical and cosmetics industries to produce high valuable compounds. They can be carried out in two ways, step by step and one-pot. If two or more enzymes are in the same reaction vessel is necessary to work out the compromise to run the reaction in optimal conditions for each enzyme. So far most of the reports of multienzymatic cascades concern on usage of free enzymes. Unfortunately using free enzymes as catalysts of reactions accomplish high cost. What is more, free enzymes are soluble in solvents which makes reuse impossible. To overcome this obstacle enzymes can be immobilized what provides heterogeneity of biocatalyst that enables reuse and easy separation of the enzyme from solvents and reaction products. Usually, immobilization increase also the thermal and operational stability of enzyme. The advantages of using immobilized multienzymes are enhanced enzyme stability, improved cascade enzymatic activity via substrate channeling, and ease of recovery for reuse. The one-pot immobilized multienzymatic cascade can be carried out in mixed or coimmobilized type. When biocatalysts are coimmobilized on the same carrier the are in close contact to each other which increase the reaction rate and catalytic efficiency, and eliminate the lag time. However, in this type providing the optimal conditions both in the process of immobilization and cascade reaction for each enzyme is complicated. Herein, we examined immobilization of 3 enzymes: D-amino acid oxidase from Rhodotorula gracilis, commercially available catalase and transketolase from Geobacillus stearothermophilus. As a support we used silica monoliths with hierarchical structure of pores. Then we checked their stability and reusability in one-pot cascade of L-erythrulose and hydroxypuryvate acid synthesis.

Keywords: biocatalysts, enzyme immobilization, multienzymatic reaction, silica carriers

Procedia PDF Downloads 122
754 Thermal Performance of an Air-Water Heat Exchanger (AWHE) Operating in Groundwater and Hot-Humid Climate

Authors: César Ramírez-Dolores, Jorge Wong-Loya, Jorge Andaverde, Caleb Becerra

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Low-depth geothermal energy can take advantage of the use of the subsoil as an air conditioning technique, being used as a passive system or coupled to an active cooling and/or heating system. This source of air conditioning is possible because at a depth less than 10 meters, the subsoil temperature is practically homogeneous and tends to be constant regardless of the climatic conditions on the surface. The effect of temperature fluctuations on the soil surface decreases as depth increases due to the thermal inertia of the soil, causing temperature stability; this effect presents several advantages in the context of sustainable energy use. In the present work, the thermal behavior of a horizontal Air-Water Heat Exchanger (AWHE) is evaluated, and the thermal effectiveness and temperature of the air at the outlet of the prototype immersed in groundwater is experimentally determined. The thermohydraulic aspects of the heat exchanger were evaluated using the Number of Transfer Units-Efficiency (NTU-ε) method under conditions of groundwater flow in a coastal region of sandy soil (southeastern Mexico) and air flow induced by a blower, the system was constructed of polyvinyl chloride (PVC) and sensors were placed in both the exchanger and the water to record temperature changes. The results of this study indicate that when the exchanger operates in groundwater, it shows high thermal gains allowing better heat transfer, therefore, it significantly reduces the air temperature at the outlet of the system, which increases the thermal effectiveness of the system in values > 80%, this passive technique is relevant for building cooling applications and could represent a significant development in terms of thermal comfort for hot locations in emerging economy countries.

Keywords: convection, earth, geothermal energy, thermal comfort

Procedia PDF Downloads 46
753 Non-Destructive Technique for Detection of Voids in the IC Package Using Terahertz-Time Domain Spectrometer

Authors: Sung-Hyeon Park, Jin-Wook Jang, Hak-Sung Kim

Abstract:

In recent years, Terahertz (THz) time-domain spectroscopy (TDS) imaging method has been received considerable interest as a promising non-destructive technique for detection of internal defects. In comparison to other non-destructive techniques such as x-ray inspection method, scanning acoustic tomograph (SAT) and microwave inspection method, THz-TDS imaging method has many advantages: First, it can measure the exact thickness and location of defects. Second, it doesn’t require the liquid couplant while it is very crucial to deliver that power of ultrasonic wave in SAT method. Third, it didn’t damage to materials and be harmful to human bodies while x-ray inspection method does. Finally, it exhibits better spatial resolution than microwave inspection method. However, this technology couldn’t be applied to IC package because THz radiation can penetrate through a wide variety of materials including polymers and ceramics except of metals. Therefore, it is difficult to detect the defects in IC package which are composed of not only epoxy and semiconductor materials but also various metals such as copper, aluminum and gold. In this work, we proposed a special method for detecting the void in the IC package using THz-TDS imaging system. The IC package specimens for this study are prepared by Packaging Engineering Team in Samsung Electronics. Our THz-TDS imaging system has a special reflection mode called pitch-catch mode which can change the incidence angle in the reflection mode from 10 o to 70 o while the others have transmission and the normal reflection mode or the reflection mode fixed at certain angle. Therefore, to find the voids in the IC package, we investigated the appropriate angle as changing the incidence angle of THz wave emitter and detector. As the results, the voids in the IC packages were successfully detected using our THz-TDS imaging system.

Keywords: terahertz, non-destructive technique, void, IC package

Procedia PDF Downloads 448
752 Innovative Technologies for Aeration and Feeding of Fish in Aquaculture with Minimal Impact on the Environment

Authors: Vasile Caunii, Andreea D. Serban, Mihaela Ivancia

Abstract:

The paper presents a new approach in terms of the circular economy of technologies for feeding and aeration of accumulations and water basins for fish farming and aquaculture. Because fish is and will be one of the main foods on the planet, the use of bio-eco-technologies is a priority for all producers. The technologies proposed in the paper want to reduce by a substantial percentage the costs of operation of ponds and water accumulation, using non-polluting technologies with minimal impact on the environment. The paper proposes two innovative, intelligent systems, fully automated that use a common platform, completely eco-friendly. One system is intended to aerate the water of the fish pond, and the second is intended to feed the fish by dispersing an optimal amount of fodder, depending on population size, age and habits. Both systems use a floating platform, regenerative energy sources, are equipped with intelligent and innovative systems, and in addition to fully automated operation, significantly reduce the costs of aerating water accumulations (natural or artificial) and feeding fish. The intelligent system used for feeding, in addition, to reduce operating costs, optimizes the amount of food, thus preventing water pollution and the development of bacteria, microorganisms. The advantages of the systems are: increasing the yield of fish production, these are green installations, with zero pollutant emissions, can be arranged anywhere on the water surface, depending on the user's needs, can operate autonomously or remotely controlled, if there is a component failure, the system provides the operator with accurate data on the issue, significantly reducing maintenance costs, transmit data about the water physical and chemical parameters.

Keywords: bio-eco-technologies, economy, environment, fish

Procedia PDF Downloads 119
751 Synthesis of Pd Nanoparticles Confined in Graphene Oxide Framework as Nano Catalyst with Improved Activity and Recyclability in Suzuki-Miyaura Cross-Coupling Reaction

Authors: Thuy Phuong Nhat Tran, Ashutosh Thakur, Toshiaki Taniike

Abstract:

Recently, covalently linked graphene oxide frameworks (GOFs) have attracted considerable attention in gas absorbance and water purification as well-defined microporous materials. In spite of their potential advantages such as a controllable pore dimension, adjustable hydrophobicity, and structural stability, these materials have been scarcely employed in heterogeneous catalysis. Here we demonstrate a novel and facile method to synthesize Pd nanoparticles (NPs) confined in a GOF (Pd@GOF). The GOF with uniform interlayer space was obtained by the intercalation of diboronic acid between graphene oxide layers. It was found that Pd NPs were generated inside the graphitic gallery spaces of the GOF, and thus, formed Pd NPs were well-dispersed with a narrow particle size distribution. The synthesized Pd@GOF emerged as an efficient nanocatalyst based on its superior performance (product yield and recyclability) toward Suzuki-Miyaura cross-coupling reaction in both polar and apolar solvents, which has been hardly observed for previously reported graphene-based Pd nanocatalysts. Furthermore, the rational comparison of the catalytic performance between two kinds of Pd@GOF (Pd NPs encapsulated in a diboronic ester-intercalated GOF and in a monoboronic ester-intercalated GOF) firmly confirmed the essential role of a rigid framework design in the stabilization of Pd NPs. Based on these results, the covalently assembled GOF was proposed as a promising scaffold for hosting noble metal NPs to construct desired metal@GOF nanocatalysts with improved activity and durability.

Keywords: graphene oxide framework, palladium nanocatalyst, pore confinement, Suzuki-Miyaura cross-coupling reaction

Procedia PDF Downloads 117
750 An Exploration of Chinese Foreign Direct Investment in Africa from Ethical and Cultural Perspectives

Authors: Yongsheng Guo

Abstract:

This study explores the perceptions and conducts of Chinese foreign direct investment (FDI) in Africa from ethical and cultural perspectives. It offers a better understanding of how ethical and cultural factors affect Chinese investment in Africa and how the investment projects performed in Africa from both Chinese investors and African stakeholders’ perceptions. It adopted a grounded theory approach and conducted 30 in-depth interviews with corporate managers. Grounded theory models are developed to link the ethical and cultural factors, actions, and consequences. Results reveal that some ethical concepts like the unity of humans and nature, benevolence, virtue and responsibility, and cultural traits including propriety, righteousness, sincerity, equilibrium, long-term orientation, and principles affect Chinese investors when making investments in Africa. Most Chinese investors harmonize with local managers, cooperate with each other, and are gentle and courteous to partners. They take stable and steady actions and invest in infrastructure and agriculture projects and adopt a virtue governance system in the organization. This study finds that consequently, Chinese investors and local partners take complementary advantages, make achievements sequentially, and therefore both sides can win. They recognize great potentials and make sustainable development in Africa to achieve the Great Together in the future. This study proposes a Chinese ethics and governance system including economic, social, and political perspectives and compares it with alternative systems. It makes implications to the world island theory and propose suggestions to solve the Clash of Civilizations problem.

Keywords: foreign direct investment, ethics, national culture, China, Africa

Procedia PDF Downloads 55
749 An Analysis of the Panel’s Perceptions on Cooking in “Metaverse Kitchen”

Authors: Minsun Kim

Abstract:

This study uses the concepts of augmented reality, virtual reality, mirror world, and lifelogging to describe “Metaverse Kitchen” that can be defined as a space in the virtual world where users can cook the dishes they want using the meal kit regardless of location or time. This study examined expert’s perceptions of cooking and food delivery services using "Metaverse Kitchen." In this study, a consensus opinion on the concept, potential pros, and cons of "Metaverse Kitchen" was derived from 20 culinary experts through the Delphi technique. The three Delphi rounds were conducted for one month, from December 2022 to January 2023. The results are as follows. First, users select and cook food after visiting the "Metaverse Kitchen" in the virtual space. Second, when a user cooks in "Metaverse Kitchen" in AR or VR, the information is transmitted to nearby restaurants. Third, the platform operating the "Metaverse Kitchen" assigns the order to the restaurant that can provide the meal kit cooked by the user in the virtual space first in the same way among these restaurants. Fourth, the user pays for the "Metaverse Kitchen", and the restaurant delivers the cooked meal kit to the user and then receives payment for the user's meal and delivery fee from the platform. Fifth, the platform company that operates the mirror world "Metaverse Kitchen" uses lifelogging to manage customers. They receive commissions from users and affiliated restaurants and operate virtual restaurant businesses using meal kits. Among the selection attributes for meal kits provided in "Metaverse Kitchen", the panelists suggested convenience, quality, and reliability as advantages and predicted relatively high price as a disadvantage. "Metaverse Kitchen" using meal kits is expected to form a new food supply system in the future society. In follow-up studies, an empirical analysis is required targeting producers and consumers.

Keywords: metaverse, meal kits, Delphi technique, Metaverse Kitchen

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748 Studies on Tolerance of Chickpea to Some Pre and Post Emergence Herbicides

Authors: Rahamdad Khan, Ijaz Ahmad Khan

Abstract:

In modern agriculture the herbicides application are considered the most effective and fast in action against all types of weeds. But it’s a fact that the herbicide applicator cannot totally secure the crop plants from the possible herbicide injuries that further leads to several destructive changes in plant biochemistry. For the purpose pots studies were undertaken to test the tolerance order of chickpea against pre- emergence herbicides (Stomp 330 EC- Dual Gold 960 EC) and post- emergence herbicides (Topik 15 WP- Puma Super 75 EW- Isoproturon 500 EW) during 2012-13 and 2013-14. The experimental design was CRD with three replications. Plant height, number of branches plant-1, number of seeds plant-1, nodulation, seed protein contents and other growth related parameters in chickpea were examined during the investigations. The results indicate that all the enquire herbicides gave a significant variation to all recorded parameter of chick pea except nodule fresh and dray weight. Moreover the toxic effect of pre-emergence herbicide on chickpea was found higher as compared to post-emergence herbicides. Minimum chickpea plant height (50.50 cm), number of nodule plant-1 (17.83) and lowest seed protein (14.13 %) was recorded in Stomp 330 EC. Similarly the outmost seeds plant-1 (29.66) and number of nodule plant-1 (21) were found for Puma Super 75 EW. The results further showed that the highest seed protein content (21.75 and 21.15 %) was recorded for control/ untreated and Puma Super 75EW. Taking under concentration the possible negative impact of the herbicides the chemical application must be minimized up to certain extent at which the crop is mostly secure. However chemical weed control has many advantages so we should train our farmer regarding the proper use of agro chemical to minimize the loses in crops while using herbicides.

Keywords: chickpea, herbicides, protein, stomp 330 EC, weed

Procedia PDF Downloads 471
747 Economic Growth: The Nexus of Oil Price Volatility and Renewable Energy Resources among Selected Developed and Developing Economies

Authors: Muhammad Siddique, Volodymyr Lugovskyy

Abstract:

This paper explores how nations might mitigate the unfavorable impacts of oil price volatility on economic growth by switching to renewable energy sources. The impacts of uncertain factor prices on economic activity are examined by looking at the Realized Volatility (RV) of oil prices rather than the more traditional method of looking at oil price shocks. The United States of America (USA), China (C), India (I), United Kingdom (UK), Germany (G), Malaysia (M), and Pakistan (P) are all included to round out the traditional literature's examination of selected nations, which focuses on oil-importing and exporting economies. Granger Causality Tests (GCT), Impulse Response Functions (IRF), and Variance Decompositions (VD) demonstrate that in a Vector Auto-Regressive (VAR) scenario, the negative impacts of oil price volatility extend beyond what can be explained by oil price shocks alone for all of the nations in the sample. Different nations have different levels of vulnerability to changes in oil prices and other factors that may play a role in a sectoral composition and the energy mix. The conventional method, which only takes into account whether a country is a net oil importer or exporter, is inadequate. The potential economic advantages of initiatives to decouple the macroeconomy from volatile commodities markets are shown through simulations of volatility shocks in alternative energy mixes (with greater proportions of renewables). It is determined that in developing countries like Pakistan, increasing the use of renewable energy sources might lessen an economy's sensitivity to changes in oil prices; nonetheless, a country-specific study is required to identify particular policy actions. In sum, the research provides an innovative justification for mitigating economic growth's dependence on stable oil prices in our sample countries.

Keywords: oil price volatility, renewable energy, economic growth, developed and developing economies

Procedia PDF Downloads 60
746 The Impact of Generative AI Illustrations on Aesthetic Symbol Consumption among Consumers: A Case Study of Japanese Anime Style

Authors: Han-Yu Cheng

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This study aims to explore the impact of AI-generated illustration works on the aesthetic symbol consumption of consumers in Taiwan. The advancement of artificial intelligence drawing has lowered the barriers to entry, enabling more individuals to easily enter the field of illustration. Using Japanese anime style as an example, with the development of Generative Artificial Intelligence (Generative AI), an increasing number of illustration works are being generated by machines, sparking discussions about aesthetics and art consumption. Through surveys and the analysis of consumer perspectives, this research investigates how this influences consumers' aesthetic experiences and the resulting changes in the traditional art market and among creators. The study reveals that among consumers in Taiwan, particularly those interested in Japanese anime style, there is a pronounced interest and curiosity surrounding the emergence of Generative AI. This curiosity is particularly notable among individuals interested in this style but lacking the technical skills required for creating such artworks. These works, rooted in elements of Japanese anime style, find ready acceptance among enthusiasts of this style due to their stylistic alignment. Consequently, they have garnered a substantial following. Furthermore, with the reduction in entry barriers, more individuals interested in this style but lacking traditional drawing skills have been able to participate in producing such works. Against the backdrop of ongoing debates about artistic value since the advent of artificial intelligence (AI), Generative AI-generated illustration works, while not entirely displacing traditional art, to a certain extent, fulfill the aesthetic demands of this consumer group, providing a similar or analogous aesthetic consumption experience. Additionally, this research underscores the advantages and limitations of Generative AI-generated illustration works within this consumption environment.

Keywords: generative AI, anime aesthetics, Japanese anime illustration, art consumption

Procedia PDF Downloads 50
745 Synthesis of Pyrimidine-Based Polymers Consist of 2-{4-[4,6-Bis-(4-Hexyl-Thiophen-2-yl)-Pyrimidin-2-yl]-Phenyl}-Thiazolo[5,4-B]Pyridine with Deep HOMO Level for Photovoltaics

Authors: Hyehyeon Lee, Jiwon Yu, Juwon Kim, Raquel Kristina Leoni Tumiar, Taewon Kim, Juae Kim, Hongsuk Suh

Abstract:

Photovoltaics, which have many advantages in cost, easy processing, and light-weight, have attracted attention. We synthesized pyrimidine-based conjugated polymers with 2-{4-[4,6-bis-(4-hexyl-thiophen-2-yl)-pyrimidin-2-yl]-phenyl}-thiazolo[5,4-b]pyridine (pPTP) which have an ability of powerful electron withdrawing and introduced into the PSCs. By Stille polymerization, we designed the conjugated polymers, pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH and pPTPTTI. The HOMO energy levels of four polymers (pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH and pPTPTTI) were at -5.61 ~ -5.89 eV, their LUMO (Lowest Unoccupied Molecular Orbital) energy levels were at -3.95 ~ -4.09 eV. The device including pPTPBDT-12 and PC71BM (1:2) indicated a V_oc of 0.67 V, a J_sc of 1.33 mA/cm², and a fill factor (FF) of 0.25, giving a power conversion efficiency (PCE) of 0.23%. The device including pPTPBDT-EH and PC71BM (1:2) indicated a V_oc of 0.72 V, a J_sc of 2.56 mA/cm², and a fill factor (FF) of 0.30, giving a power conversion efficiency of 0.56%. The device including pPTPBDTT-EH and PC71BM (1:2) indicated a V_oc of 0.72 V, a J_sc of 3.61 mA/cm², and a fill factor (FF) of 0.29, giving a power conversion efficiency of 0.74%. The device including pPTPTTI and PC71BM (1:2) indicated a V_oc of 0.83 V, a J_sc of 4.41 mA/cm², and a fill factor (FF) of 0.31, giving a power conversion efficiency of 1.13%. Therefore, pPTPBDT-12, pPTPBDT-EH, pPTPBDTT-EH, and pPTPTTI were synthesized by Stille polymerization. And We find one of the best efficiency for these polymers, called pPTPTTI. Their optical properties were measured and the results show that pyrimidine-based polymers especially like pPTPTTI have a great promise to act as the donor of the active layer.

Keywords: polymer solar cells, pyrimidine-based polymers, photovoltaics, conjugated polymer

Procedia PDF Downloads 176
744 Lateral Torsional Buckling Resistance of Trapezoidally Corrugated Web Girders

Authors: Annamária Käferné Rácz, Bence Jáger, Balázs Kövesdi, László Dunai

Abstract:

Due to the numerous advantages of steel corrugated web girders, its application field is growing for bridges as well as for buildings. The global stability behavior of such girders is significantly larger than those of conventional I-girders with flat web, thus the application of the structural steel material can be significantly reduced. Design codes and specifications do not provide clear and complete rules or recommendations for the determination of the lateral torsional buckling (LTB) resistance of corrugated web girders. Therefore, the authors made a thorough investigation regarding the LTB resistance of the corrugated web girders. Finite element (FE) simulations have been performed to develop new design formulas for the determination of the LTB resistance of trapezoidally corrugated web girders. FE model is developed considering geometrical and material nonlinear analysis using equivalent geometric imperfections (GMNI analysis). The equivalent geometric imperfections involve the initial geometric imperfections and residual stresses coming from rolling, welding and flame cutting. Imperfection sensitivity analysis was performed to determine the necessary magnitudes regarding only the first eigenmodes shape imperfections. By the help of the validated FE model, an extended parametric study is carried out to investigate the LTB resistance for different trapezoidal corrugation profiles. First, the critical moment of a specific girder was calculated by FE model. The critical moments from the FE calculations are compared to the previous analytical calculation proposals. Then, nonlinear analysis was carried out to determine the ultimate resistance. Due to the numerical investigations, new proposals are developed for the determination of the LTB resistance of trapezoidally corrugated web girders through a modification factor on the design method related to the conventional flat web girders.

Keywords: corrugated web, lateral torsional buckling, critical moment, FE modeling

Procedia PDF Downloads 265
743 Clinical and Radiological Features of Adenomyosis and Its Histopathological Correlation

Authors: Surabhi Agrawal Kohli, Sunita Gupta, Esha Khanuja, Parul Garg, P. Gupta

Abstract:

Background: Adenomyosis is a common gynaecological condition that affects the menstruating women. Uterine enlargement, dysmenorrhoea, and menorrhagia are regarded as the cardinal clinical symptoms of adenomyosis. Classically it was thought, compared with ultrasonography, when adenomyosis is suspected, MRI enables more accurate diagnosis of the disease. Materials and Methods: 172 subjects were enrolled after an informed consent that had complaints of HMB, dyspareunia, dysmenorrhea, and chronic pelvic pain. Detailed history of the enrolled subjects was taken, followed by a clinical examination. These patients were then subjected to TVS where myometrial echo texture, presence of myometrial cysts, blurring of endomyometrial junction was noted. MRI was followed which noted the presence of junctional zone thickness and myometrial cysts. After hysterectomy, histopathological diagnosis was obtained. Results: 78 participants were analysed. The mean age was 44.2 years. 43.5% had parity of 4 or more. heavy menstrual bleeding (HMB) was present in 97.8% and dysmenorrhea in 93.48 % of HPE positive patient. Transvaginal sonography (TVS) and MRI had a sensitivity of 89.13% and 80.43%, specificity of 90.62% and 84.37%, positive likelihood ratio of 9.51 and 5.15, negative likelihood ratio of 0.12 and 0.23, positive predictive value of 93.18% and 88.1%, negative predictive value of 85.29% and 75% and a diagnostic accuracy of 89.74% and 82.5%. Comparison of sensitivity (p=0.289) and specificity (p=0.625) showed no statistically significant difference between TVS and MRI. Conclusion: Prevalence of 30.23%. HMB with dysmenorrhoea and chronic pelvic pain helps in diagnosis. TVS (Endomyometrial junction blurring) is both sensitive and specific in diagnosing adenomyosis without need for additional diagnostic tool. Both TVS and MRI are equally efficient, however because of certain additional advantages of TVS over MRI, it may be used as the first choice of imaging. MRI may be used additionally in difficult cases as well as in patients with existing co-pathologies.

Keywords: adenomyosis, heavy menstrual bleeding, MRI, TVS

Procedia PDF Downloads 465
742 Physical, Microstructural and Functional Quality Improvements of Cassava-Sorghum Composite Snacks

Authors: Adil Basuki Ahza, Michael Liong, Subarna Suryatman

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Healthy chips now dominating the snack market shelves. More than 80% processed snack foods in the market are chips. This research takes the advantages of twin extrusion technology to produce two types of product, i.e. directly expanded and intermediate ready-to-fry or microwavable chips. To improve the functional quality, the cereal-tuber based mix was enriched with antioxidant rich mix of temurui, celery, carrot and isolated soy protein (ISP) powder. Objectives of this research were to find best composite cassava-sorghum ratio, i.e. 60:40, 70:30 and 80:20, to optimize processing conditions of extrusion and study the microstructural, physical and sensorial characteristics of the final products. Optimization was firstly done by applying metering section of extruder barrel temperatures of 120, 130 and 140 °C with screw speeds of 150, 160 and 170 rpm to produce direct expanded product. The intermediate product was extruded in 100 °C and 100 rpm screw speed with feed moisture content of 35, 40 and 45%. The directly expanded products were analyzed for color, hardness, density, microstructure, and organoleptic properties. The results showed that interaction of ratio of cassava-sorghum and cooking methods affected the product's color, hardness, and bulk density (p<0.05). Extrusion processing conditions also significantly affected product's microstructure (p<0.05). The direct expanded snacks of 80:20 cassava-sorghum ratio and fried expanded one 70:30 and 80:20 ratio shown the best organoleptic score (slightly liked) while baking the intermediate product with microwave were resulted sensorial not acceptable quality chips.

Keywords: cassava-sorghum composite, extrusion, microstructure, physical characteristics

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741 Real-Time Radar Tracking Based on Nonlinear Kalman Filter

Authors: Milca F. Coelho, K. Bousson, Kawser Ahmed

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To accurately track an aerospace vehicle in a time-critical situation and in a highly nonlinear environment, is one of the strongest interests within the aerospace community. The tracking is achieved by estimating accurately the state of a moving target, which is composed of a set of variables that can provide a complete status of the system at a given time. One of the main ingredients for a good estimation performance is the use of efficient estimation algorithms. A well-known framework is the Kalman filtering methods, designed for prediction and estimation problems. The success of the Kalman Filter (KF) in engineering applications is mostly due to the Extended Kalman Filter (EKF), which is based on local linearization. Besides its popularity, the EKF presents several limitations. To address these limitations and as a possible solution to tracking problems, this paper proposes the use of the Ensemble Kalman Filter (EnKF). Although the EnKF is being extensively used in the context of weather forecasting and it is being recognized for producing accurate and computationally effective estimation on systems with a very high dimension, it is almost unknown by the tracking community. The EnKF was initially proposed as an attempt to improve the error covariance calculation, which on the classic Kalman Filter is difficult to implement. Also, in the EnKF method the prediction and analysis error covariances have ensemble representations. These ensembles have sizes which limit the number of degrees of freedom, in a way that the filter error covariance calculations are a lot more practical for modest ensemble sizes. In this paper, a realistic simulation of a radar tracking was performed, where the EnKF was applied and compared with the Extended Kalman Filter. The results suggested that the EnKF is a promising tool for tracking applications, offering more advantages in terms of performance.

Keywords: Kalman filter, nonlinear state estimation, optimal tracking, stochastic environment

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740 Phase Changing Dicationic Polymeric Ionic Liquid with CO2 Capture Abilities

Authors: Swati Sundararajan, Asit B. Samui, Prashant S. Kulkarni

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Polymeric ionic liquids combine the properties of ionic liquids and polymers into a single material which has gained massive interest in the recent years. These ionic liquids offer several advantages such as high phase change enthalpy, wide temperature range, chemical and thermal stability, non-volatility and the ability to make them task-specific. Separation of CO2 is an area of critical importance due to the concerns over greenhouse gasses leading to global warming. Thermal energy storage materials, also known as phase change materials absorb latent heat during fusion process and release the absorbed energy to the surrounding environment during crystallization. These materials retain this property over a number of cycles and therefore, are useful for bridging the gap between energy requirement and use. In an effort to develop materials, which will help in minimizing the growing energy demand and environmental concerns, a series of dicationic poly(ethylene glycol) based polymeric ionic liquids were synthesized. One part of an acrylate of poly(ethylene glycol) was reacted with imidazolium quarternizing agent and the second part was reacted with triazolium quarternizing agent. These two different monomers were then copolymerized to prepare dicationic polymeric ionic liquid. These materials were characterized for solid-liquid phase transition and the enthalpy by using differential scanning calorimetry. The CO2 capture studies were performed on a fabricated setup with varying pressure range from 1-20 atm. The findings regarding the prepared materials, having potential dual applications in the fields of thermal energy storage and CO2 capture, will be discussed in the presentation.

Keywords: CO2 capture, phase change materials, polyethylene glycol, polymeric ionic liquids, thermal energy storage

Procedia PDF Downloads 230
739 The Effectiveness of Using Picture Storybooks on Young English as a Foreign Language Learners for English Vocabulary Acquisition and Moral Education: A Case Study

Authors: Tiffany Yung Hsuan Ma

Abstract:

The Whole Language Approach, which gained prominence in the 1980s, and the increasing emphasis on multimodal resources in educational research have elevated the utilization of picture books in English as a foreign language (EFL) instruction. This approach underscores real-world language application, providing EFL learners with a range of sensory stimuli, including visual elements. Additionally, the substantial impact of picture books on fostering prosocial behaviors in children has garnered recognition. These narratives offer opportunities to impart essential values such as kindness, fairness, and respect. Examining how picture books enhance vocabulary acquisition can offer valuable insights for educators in devising engaging language activities conducive to a positive learning environment. This research entails a case study involving two kindergarten-aged EFL learners and employs qualitative methods, including worksheets, observations, and interviews with parents. It centers on three pivotal inquiries: (1) The extent of young learners' acquisition of essential vocabulary, (2) The influence of these books on their behavior at home, and (3) Effective teaching strategies for the seamless integration of picture storybooks into EFL instruction for young learners. The findings can provide guidance to parents, educators, curriculum developers, and policymakers regarding the advantages and optimal approaches to incorporating picture books into language instruction. Ultimately, this research has the potential to enhance English language learning outcomes and promote moral education within the Taiwanese EFL context.

Keywords: EFL, vocabulary acquisition, young learners, picture book, moral education

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738 Predicting Foreign Direct Investment of IC Design Firms from Taiwan to East and South China Using Lotka-Volterra Model

Authors: Bi-Huei Tsai

Abstract:

This work explores the inter-region investment behaviors of integrated circuit (IC) design industry from Taiwan to China using the amount of foreign direct investment (FDI). According to the mutual dependence among different IC design industrial locations, Lotka-Volterra model is utilized to explore the FDI interactions between South and East China. Effects of inter-regional collaborations on FDI flows into China are considered. Evolutions of FDIs into South China for IC design industry significantly inspire the subsequent FDIs into East China, while FDIs into East China for Taiwan’s IC design industry significantly hinder the subsequent FDIs into South China. The supply chain along IC industry includes IC design, manufacturing, packing and testing enterprises. I C manufacturing, packaging and testing industries depend on IC design industry to gain advanced business benefits. The FDI amount from Taiwan’s IC design industry into East China is the greatest among the four regions: North, East, Mid-West and South China. The FDI amount from Taiwan’s IC design industry into South China is the second largest. If IC design houses buy more equipment and bring more capitals in South China, those in East China will have pressure to undertake more FDIs into East China to maintain the leading position advantages of the supply chain in East China. On the other hand, as the FDIs in East China rise, the FDIs in South China will successively decline since capitals have concentrated in East China. Prediction of Lotka-Volterra model in FDI trends is accurate because the industrial interactions between the two regions are included. Finally, this work confirms that the FDI flows cannot reach a stable equilibrium point, so the FDI inflows into East and South China will expand in the future.

Keywords: Lotka-Volterra model, foreign direct investment, competitive, Equilibrium analysis

Procedia PDF Downloads 339
737 The Fundamental Research and Industrial Application on CO₂+O₂ in-situ Leaching Process in China

Authors: Lixin Zhao, Genmao Zhou

Abstract:

Traditional acid in-situ leaching (ISL) is not suitable for the sandstone uranium deposit with low permeability and high content of carbonate minerals, because of the blocking of calcium sulfate precipitates. Another factor influences the uranium acid in-situ leaching is that the pyrite in ore rocks will react with oxidation reagent and produce lots of sulfate ions which may speed up the precipitation process of calcium sulphate and consume lots of oxidation reagent. Due to the advantages such as less chemical reagent consumption and groundwater pollution, CO₂+O₂ in-situ leaching method has become one of the important research areas in uranium mining. China is the second country where CO₂+O₂ ISL has been adopted in industrial uranium production of the world. It is shown that the CO₂+O₂ ISL in China has been successfully developed. The reaction principle, technical process, well field design and drilling engineering, uranium-bearing solution processing, etc. have been fully studied. At current stage, several uranium mines use CO₂+O₂ ISL method to extract uranium from the ore-bearing aquifers. The industrial application and development potential of CO₂+O₂ ISL method in China are summarized. By using CO₂+O₂ neutral leaching technology, the problem of calcium carbonate and calcium sulfate precipitation have been solved during uranium mining. By reasonably regulating the amount of CO₂ and O₂, related ions and hydro-chemical conditions can be controlled within the limited extent for avoiding the occurrence of calcium sulfate and calcium carbonate precipitation. Based on this premise, the demand of CO₂+O₂ uranium leaching has been met to the maximum extent, which not only realizes the effective leaching of uranium, but also avoids the occurrence and precipitation of calcium carbonate and calcium sulfate, realizing the industrial development of the sandstone type uranium deposit.

Keywords: CO₂+O₂ ISL, industrial production, well field layout, uranium processing

Procedia PDF Downloads 146
736 Performance Analysis of Pumps-as-Turbine Under Cavitating Conditions

Authors: Calvin Stephen, Biswajit Basu, Aonghus McNabola

Abstract:

Market liberalization in the power sector has led to the emergence of micro-hydropower schemes that are dependent on the use of pumps-as-turbines in applications that were not suitable as potential hydropower sites in earlier years. These applications include energy recovery in water supply networks, sewage systems, irrigation systems, alcohol breweries, underground mining and desalination plants. As a result, there has been an accelerated adoption of pumpsas-turbine technology due to the economic advantages it presents in comparison to the conventional turbines in the micro-hydropower space. The performance of this machines under cavitation conditions, however, is not well understood as there is a deficiency of knowledge in literature focused on their turbine mode of operation. In hydraulic machines, cavitation is a common occurrence which needs to be understood to safeguard them and prolong their operation life. The overall purpose of this study is to investigate the effects of cavitation on the performance of a pumps-as-turbine system over its entire operating range. At various operating speeds, the cavitating region is identified experimentally while monitoring the effects this has on the power produced by the machine. Initial results indicate occurrence of cavitation at higher flow rates for lower operating speeds and at lower flow rates at higher operating speeds. This implies that for cavitation free operation, low speed pumps-as-turbine must be used for low flow rate conditions whereas for sites with higher flow rate conditions high speed turbines should be adopted. Such a complete understanding of pumps-as-turbine suction performance can aid avoid cavitation induced failures hence improved reliability of the micro-hydropower plant.

Keywords: cavitation, micro-hydropower, pumps-as-turbine, system design

Procedia PDF Downloads 82
735 Ontology based Fault Detection and Diagnosis system Querying and Reasoning examples

Authors: Marko Batic, Nikola Tomasevic, Sanja Vranes

Abstract:

One of the strongholds in the ubiquitous efforts related to the energy conservation and energy efficiency improvement is represented by the retrofit of high energy consumers in buildings. In general, HVAC systems represent the highest energy consumers in buildings. However they usually suffer from mal-operation and/or malfunction, causing even higher energy consumption than necessary. Various Fault Detection and Diagnosis (FDD) systems can be successfully employed for this purpose, especially when it comes to the application at a single device/unit level. In the case of more complex systems, where multiple devices are operating in the context of the same building, significant energy efficiency improvements can only be achieved through application of comprehensive FDD systems relying on additional higher level knowledge, such as their geographical location, served area, their intra- and inter- system dependencies etc. This paper presents a comprehensive FDD system that relies on the utilization of common knowledge repository that stores all critical information. The discussed system is deployed as a test-bed platform at the two at Fiumicino and Malpensa airports in Italy. This paper aims at presenting advantages of implementation of the knowledge base through the utilization of ontology and offers improved functionalities of such system through examples of typical queries and reasoning that enable derivation of high level energy conservation measures (ECM). Therefore, key SPARQL queries and SWRL rules, based on the two instantiated airport ontologies, are elaborated. The detection of high level irregularities in the operation of airport heating/cooling plants is discussed and estimation of energy savings is reported.

Keywords: airport ontology, knowledge management, ontology modeling, reasoning

Procedia PDF Downloads 499
734 Graph Neural Network-Based Classification for Disease Prediction in Health Care Heterogeneous Data Structures of Electronic Health Record

Authors: Raghavi C. Janaswamy

Abstract:

In the healthcare sector, heterogenous data elements such as patients, diagnosis, symptoms, conditions, observation text from physician notes, and prescriptions form the essentials of the Electronic Health Record (EHR). The data in the form of clear text and images are stored or processed in a relational format in most systems. However, the intrinsic structure restrictions and complex joins of relational databases limit the widespread utility. In this regard, the design and development of realistic mapping and deep connections as real-time objects offer unparallel advantages. Herein, a graph neural network-based classification of EHR data has been developed. The patient conditions have been predicted as a node classification task using a graph-based open source EHR data, Synthea Database, stored in Tigergraph. The Synthea DB dataset is leveraged due to its closer representation of the real-time data and being voluminous. The graph model is built from the EHR heterogeneous data using python modules, namely, pyTigerGraph to get nodes and edges from the Tigergraph database, PyTorch to tensorize the nodes and edges, PyTorch-Geometric (PyG) to train the Graph Neural Network (GNN) and adopt the self-supervised learning techniques with the AutoEncoders to generate the node embeddings and eventually perform the node classifications using the node embeddings. The model predicts patient conditions ranging from common to rare situations. The outcome is deemed to open up opportunities for data querying toward better predictions and accuracy.

Keywords: electronic health record, graph neural network, heterogeneous data, prediction

Procedia PDF Downloads 65
733 Full-Scale 3D Simulation of the Electroslag Rapid Remelting Process

Authors: E. Karimi-Sibaki, A. Kharicha, M. Wu, A. Ludwig

Abstract:

The standard electroslag remelting (ESR) process can ideally control the solidification of an ingot and produce homogeneous structure with minimum defects. However, the melt rate of electrode is rather low that makes the whole process uneconomical especially to produce small ingot sizes. In contrast, continuous casting is an economical process to produce small ingots such as billets at high casting speed. Unfortunately, deep liquid melt pool forms in the billet ingot of continuous casting that leads to center porosity and segregation. As such, continuous casting is not suitable to produce segregation prone alloys like tool steel or several super alloys. On the other hand, the electro slag rapid remelting (ESRR) process has advantages of both traditional ESR and continuous casting processes to produce billets. In the ESRR process, a T-shaped mold is used including a graphite ring that takes major amount of current through the mold. There are only a few reports available in the literature discussing about this topic. The research on the ESRR process is currently ongoing aiming to improve the design of the T-shaped mold, to decrease overall heat loss in the process, and to obtain a higher temperature at metal meniscus. In the present study, a 3D model is proposed to investigate the electromagnetic, thermal, and flow fields in the whole process as well as solidification of the billet ingot. We performed a fully coupled numerical simulation to explore the influence of the electromagnetically driven flow (MHD) on the thermal field in the slag and ingot. The main goal is to obtain some fundamental understanding of the formation of melt pool of the solidifying billet ingot in the ESRR process.

Keywords: billet ingot, magnetohydrodynamics (mhd), numerical simulation, remelting, solidification, t-shaped mold.

Procedia PDF Downloads 278
732 Bayesian System and Copula for Event Detection and Summarization of Soccer Videos

Authors: Dhanuja S. Patil, Sanjay B. Waykar

Abstract:

Event detection is a standout amongst the most key parts for distinctive sorts of area applications of video data framework. Recently, it has picked up an extensive interest of experts and in scholastics from different zones. While detecting video event has been the subject of broad study efforts recently, impressively less existing methodology has considered multi-model data and issues related efficiency. Start of soccer matches different doubtful circumstances rise that can't be effectively judged by the referee committee. A framework that checks objectively image arrangements would prevent not right interpretations because of some errors, or high velocity of the events. Bayesian networks give a structure for dealing with this vulnerability using an essential graphical structure likewise the probability analytics. We propose an efficient structure for analysing and summarization of soccer videos utilizing object-based features. The proposed work utilizes the t-cherry junction tree, an exceptionally recent advancement in probabilistic graphical models, to create a compact representation and great approximation intractable model for client’s relationships in an interpersonal organization. There are various advantages in this approach firstly; the t-cherry gives best approximation by means of junction trees class. Secondly, to construct a t-cherry junction tree can be to a great extent parallelized; and at last inference can be performed utilizing distributed computation. Examination results demonstrates the effectiveness, adequacy, and the strength of the proposed work which is shown over a far reaching information set, comprising more soccer feature, caught at better places.

Keywords: summarization, detection, Bayesian network, t-cherry tree

Procedia PDF Downloads 297
731 Pain Management in Burn Wounds with Dual Drug Loaded Double Layered Nano-Fiber Based Dressing

Authors: Sharjeel Abid, Tanveer Hussain, Ahsan Nazir, Abdul Zahir, Nabyl Khenoussi

Abstract:

Localized application of drug has various advantages and fewer side effects as compared with other methods. Burn patients suffer from swear pain and the major aspects that are considered for burn victims include pain and infection management. Nano-fibers (NFs) loaded with drug, applied on local wound area, can solve these problems. Therefore, this study dealt with the fabrication of drug loaded NFs for better pain management. Two layers of NFs were fabricated with different drugs. Contact layer was loaded with Gabapentin (a nerve painkiller) and the second layer with acetaminophen. The fabricated dressing was characterized using scanning electron microscope, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction and UV-Vis Spectroscopy. The double layered based NFs dressing was designed to have both initial burst release followed by slow release to cope with pain for two days. The fabricated nanofibers showed diameter < 300 nm. The liquid absorption capacity of the NFs was also checked to deal with the exudate. The fabricated double layered dressing with dual drug loading and release showed promising results that could be used for dealing pain in burn victims. It was observed that by the addition of drug, the size of nanofibers was reduced, on the other hand, the crystallinity %age was increased, and liquid absorption decreased. The combination of fast nerve pain killer release followed by slow release of non-steroidal anti-inflammatory drug could be a good tool to reduce pain in a more secure manner with fewer side effects.

Keywords: pain management, burn wounds, nano-fibers, controlled drug release

Procedia PDF Downloads 228
730 Mechanical Advantages of the ‘KZ Bag’ on Spine and Posture of School Aged Children

Authors: Khulood Zahran

Abstract:

Background and Purpose: The effects of backpack on 'school-age' children (Age 9–12) years, have been a critical subject of discussion throughout the past years. It has been one of the factors that contribute to a bad posture for 40% to 70% of developed countries. A child carrying a heavy backpack for a prolonged period, on a daily base has shown significant changes in the child's spinal posture, foot shape, and gait. The back pain caused by the compensatory posture, or "Backpack syndrome", is also known for its headaches, fatigue, cervical and lumber pain caused by the abnormal body posture. The child tends to balance himself by bending forward to match the heavy backpack, moving his Centre of Gravity forward, resulting in decreased lumber lordosis and increased thoracic kyphosis. Since currently available bags have not addressed the weight distribution issue till now. Therefore, KZ bag is believed to prevent the huge backward shift of COG due to the load, and hence all the symptoms accompanied. This is thought to be possible by combining the design of a normal backpack with a messenger bag. The purpose of this study is to investigate the improvement of the child's spine and to minimize the compensatory posture after using the KZ bag. Materials and Methods: KZ bag would compromise the pros of a messenger bag (keeping the COG in place) by a diagonal load strap and of a backpack (distributing the load on both shoulders) by connecting another load strap parallel to the sagittal plane of the body. The design would be made adjustable to match the child's height, and the bag load kept within limits, (10-15%) of the child's body weight. Measurements of Postural angles (Cervical, shoulders, and Trunk) would be taken after the use of KZ bag for a specified period. Conclusion: KZ bag will prove an improved distribution of weight of the bag on the child's body, and reduce the degree of the compensatory posture, that occurs in the attempt to balance the external weight of the bag.

Keywords: backpack, backpack syndrome, posture, spine

Procedia PDF Downloads 173
729 The Impact of Ultrasonicator on the Vertical and Horizontal Mixing Profile of Petrol-Bioethanol

Authors: D. Nkazi, S. E. Iyuke, J. Mulopo

Abstract:

Increasing global energy demand as well as air quality concerns have in recent years led to the search for alternative clean fuels to replace fossil fuels. One such alternative is the blending of petrol with ethanol, which has numerous advantages such ethanol’s ability to act as oxygenate thus reducing the carbon monoxide emissions from the exhaust of internal combustion engines of vehicles. However, the hygroscopic nature of ethanol is a major concern in obtaining a perfectly homogenized petrol-ethanol fuel. This problem has led to the study of ways of homogenizing the petrol-ethanol mixtures. During the blending process, volumes fraction of ethanol and petrol were studied with respect to the depth within the storage container to confirm homogenization of the blend and time of storage. The results reveal that the density of the mixture was constant. The binodal curve of the ternary diagram shows an increase of homogeneous region, indicating an improved of interaction between water and petrol. The concentration distribution in the reactor showed proof of cavitation formation since in both directions, the variation of concentration with both time and distance was found to be oscillatory. On comparing the profiles in both directions, the concentration gradient, diffusion flux, and energy and diffusion rates were found to be higher in the vertical direction compared to the horizontal direction. It was therefore concluded that ultrasonication creates cavitation in the mixture which enhances mass transfer and mixing of ethanol and petrol. The horizontal direction was found to be the diffusion rate limiting step which proposed that the blender should have a larger height to diameter ratio. It is, however, recommended that further studies be done on the rate-limiting step so as to have actual dimensions of the reactor.

Keywords: ultrasonication, petrol, ethanol, concentration

Procedia PDF Downloads 342
728 Islamic Banking: A New Trend towards the Development of Banking Law

Authors: Inese Tenberga

Abstract:

Undoubtedly, the focus of the present capitalist system of finance has shifted from the concept of productivity of money to the ‘cult of money’, which is characterized by such notions as speculative activity, squander, self-profit, vested interest, etc. The author is certain that a civilized society cannot follow this economic path any longer and therefore suggests that one solution would be to integrate the Islamic financial model in the banking sector of the EU to overcome its economic vulnerability and structurally transform its economies or build resilience against shocks and crisis. The researcher analyses the Islamic financial model, which is providing the basis for the concept of non-productivity of money, and proposes to consider it as a new paradigm of economic thinking. The author argues that it seeks to establish a broad-based economic well-being with an optimum rate of economic growth, socio-economic justice, equitable distribution of income and wealth. Furthermore, the author analyses and proposes to use the experience of member states of the Islamic Development Bank for the formation of a new EU interest free banking. It is offered to create within the EU banking system a credit sector and investment sector respectively. As a part of the latter, it is recommended to separate investment banks specializing in speculative investments and non­speculative investment banks. Meanwhile, understanding of the idea of Islamic banking exclusively from the perspective of the manner of yielding profit that differs from credit banking, without considering the legal, social, ethical guidelines of Islam impedes to value objectively the advantages of this type of financial activities at the non-Islamic jurisdictions. However, the author comes to the conclusion the imperative of justice and virtue, which is inherent to all of us, exists regardless of religion. The author concludes that the global community should adopt the experience of the Muslim countries and focus on the Islamic banking model.

Keywords: credit sector, EU banking system, investment sector, Islamic banking

Procedia PDF Downloads 144
727 Machinability Analysis in Drilling Flax Fiber-Reinforced Polylactic Acid Bio-Composite Laminates

Authors: Amirhossein Lotfi, Huaizhong Li, Dzung Viet Dao

Abstract:

Interest in natural fiber-reinforced composites (NFRC) is progressively growing both in terms of academia research and industrial applications thanks to their abundant advantages such as low cost, biodegradability, eco-friendly nature and relatively good mechanical properties. However, their widespread use is still presumed as challenging because of the specificity of their non-homogeneous structure, limited knowledge on their machinability characteristics and parameter settings, to avoid defects associated with the machining process. The present work is aimed to investigate the effect of the cutting tool geometry and material on the drilling-induced delamination, thrust force and hole quality produced when drilling a fully biodegradable flax/poly (lactic acid) composite laminate. Three drills with different geometries and material were used at different drilling conditions to evaluate the machinability of the fabricated composites. The experimental results indicated that the choice of cutting tool, in terms of material and geometry, has a noticeable influence on the cutting thrust force and subsequently drilling-induced damages. The lower value of thrust force and better hole quality was observed using high-speed steel (HSS) drill, whereas Carbide drill (with point angle of 130o) resulted in the highest value of thrust force. Carbide drill presented higher wear resistance and stability in variation of thrust force with a number of holes drilled, while HSS drill showed the lower value of thrust force during the drilling process. Finally, within the selected cutting range, the delamination damage increased noticeably with feed rate and moderately with spindle speed.

Keywords: natural fiber reinforced composites, delamination, thrust force, machinability

Procedia PDF Downloads 108