Search results for: high performance fiber reinforced concrete
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30372

Search results for: high performance fiber reinforced concrete

15792 Multi-Objective Optimal Threshold Selection for Similarity Functions in Siamese Networks for Semantic Textual Similarity Tasks

Authors: Kriuk Boris, Kriuk Fedor

Abstract:

This paper presents a comparative study of fundamental similarity functions for Siamese networks in semantic textual similarity (STS) tasks. We evaluate various similarity functions using the STS Benchmark dataset, analyzing their performance and stability. Additionally, we introduce a multi-objective approach for optimal threshold selection. Our findings provide insights into the effectiveness of different similarity functions and offer a straightforward method for threshold selection optimization, contributing to the advancement of Siamese network architectures in STS applications.

Keywords: siamese networks, semantic textual similarity, similarity functions, STS benchmark dataset, threshold selection

Procedia PDF Downloads 27
15791 Keeping Education Non-Confessional While Teaching Children about Religion

Authors: Tünde Puskás, Anita Andersson

Abstract:

This study is part of a research project about whether religion is considered as part of Swedish cultural heritage in Swedish preschools. Our aim in this paper is to explore how a Swedish preschool balance between keeping the education non-confessional and at the same time teaching children about a particular tradition, Easter.The paper explores how in a Swedish preschool with a religious profile teachers balance between keeping education non-confessional and teaching about a tradition with religious roots. The point of departure for the theoretical frame of our study is that practical considerations in pedagogical situations are inherently dilemmatic. The dilemmas that are of interest for our study evolve around formalized, intellectual ideologies, such us multiculturalism and secularism that have an impact on everyday practice. Educational dilemmas may also arise in the intersections of the formalized ideology of non-confessionalism, prescribed in policy documents and the common sense understandings of what is included in what is understood as Swedish cultural heritage. In this paper, religion is treated as a human worldview that, similarly to secular ideologies, can be understood as a system of thought. We make use of Ninian Smart's theoretical framework according to which in modern Western world religious and secular ideologies, as human worldviews, can be studied from the same analytical framework. In order to be able to study the distinctive character of human worldviews Smart introduced a multi-dimensional model within which the different dimensions interact with each other in various ways and to different degrees. The data for this paper is drawn from fieldwork carried out in 2015-2016 in the form of video ethnography. The empirical material chosen consists of a video recording of a specific activity during which the preschool group took part in an Easter play performed in the local church. The analysis shows that the policy of non-confessionalism together with the idea that teaching covering religious issues must be purely informational leads in everyday practice to dilemmas about what is considered religious. At the same time what the adults actually do with religion fulfills six of seven dimensions common to religious traditions as outlined by Smart. What we can also conclude from the analysis is that whether it is religion or a cultural tradition that is thought through the performance the children watched in the church depends on how the concept of religion is defined. The analysis shows that the characters of the performance themselves understood religion as the doctrine of Jesus' resurrection from the dead. This narrow understanding of religion enabled them indirectly to teach about the traditions and narratives surrounding Easter while avoiding teaching religion as a belief system.

Keywords: non-confessional education, preschool, religion, tradition

Procedia PDF Downloads 156
15790 The Term Structure of Government Bond Yields in an Emerging Market: Empirical Evidence from Pakistan Bond Market

Authors: Wali Ullah, Muhammad Nishat

Abstract:

The study investigates the extent to which the so called Nelson-Siegel model (DNS) and its extended version that accounts for time varying volatility (DNS-EGARCH) can optimally fit the yield curve and predict its future path in the context of an emerging economy. For the in-sample fit, both models fit the curve remarkably well even in the emerging markets. However, the DNS-EGARCH model fits the curve slightly better than the DNS. Moreover, both specifications of yield curve that are based on the Nelson-Siegel functional form outperform the benchmark VAR forecasts at all forecast horizons. The DNS-EGARCH comes with more precise forecasts than the DNS for the 6- and 12-month ahead forecasts, while the two have almost similar performance in terms of RMSE for the very short forecast horizons.

Keywords: yield curve, forecasting, emerging markets, Kalman filter, EGARCH

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15789 Elaboration of Sustainable Luminescence Material Based on Rare Earth Complexes for Solar Energy Conversion

Authors: Othmane Essahili, Mohamed Ilsouk, Carine Duhayon, Omar Moudam

Abstract:

Due to their excellent and promising properties, a great deal of attention has recently been devoted to luminescent materials, particularly those utilizing rare earth elements. These materials play an essential role in low-cost energy conversion technology applications, such as luminescent solar concentrators (LSCs). They also have potential applications in Agri-PV systems and smart building windows. Luminescent materials based on europium (III) complexes are known for their high luminescence efficiency, long fluorescence lifetimes, and sharp emission bands. However, they present certain drawbacks related to their limited absorption capacity due to the forbidden 4f-4f electronic transitions. To address these drawbacks, using β-diketonate ligands as sensitizers appears as a promising solution to enhance luminescence intensity through the antenna effect, where the ligand's excited energy is transferred to the europium ions. In this study, we synthesized β-diketonate-based europium complexes with phenanthroline derivatives, modified with various methyl groups, to examine their effects on the complexes' stability in poly(methyl methacrylate) (PMMA) films. Our findings reveal that these complexes exhibit remarkable red emission and high photoluminescence quantum yield. Stability tests under different conditions for 1200 hours showed that complexes with a higher number of methyl substitutions offer improved photoluminescent stability and resistance to degradation, particularly in outdoor settings. This research underscores the potential of chemically tuned phenanthroline ligands in developing stable, efficient luminescent materials for future optoelectronic devices, including efficient and durable LSCs.

Keywords: luminescent materials, photochemistry, luminescent solar concentrators, β-diketonate-based europium complexes

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15788 Forecasting Solid Waste Generation in Turkey

Authors: Yeliz Ekinci, Melis Koyuncu

Abstract:

Successful planning of solid waste management systems requires successful prediction of the amount of solid waste generated in an area. Waste management planning can protect the environment and human health, hence it is tremendously important for countries. The lack of information in waste generation can cause many environmental and health problems. Turkey is a country that plans to join European Union, hence, solid waste management is one of the most significant criteria that should be handled in order to be a part of this community. Solid waste management system requires a good forecast of solid waste generation. Thus, this study aims to forecast solid waste generation in Turkey. Artificial Neural Network and Linear Regression models will be used for this aim. Many models will be run and the best one will be selected based on some predetermined performance measures.

Keywords: forecast, solid waste generation, solid waste management, Turkey

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15787 The Genesis of the Anomalous Sernio Fan (Valtellina, Northern Italy)

Authors: Erika De Finis, Paola Gattinoni, Laura Scesi

Abstract:

Massive rock avalanches formed some of the largest landslide deposits on Earth and they represent one of the major geohazards in high-relief mountains. This paper interprets a very large sedimentary fan (the Sernio fan, Valtellina, Northern Italy), located 20 Km SW from Val Pola Rock avalanche (1987), as the deposit of a partial collapse of a Deep Seated Gravitational Slope Deformation (DSGSD), afterwards eroded and buried by debris flows. The proposed emplacement sequence has been reconstructed based on geomorphological, structural and mechanical evidences. The Sernio fan is actually considered anomalous with reference to the very high ratio between the fan area (about 4.5km2) and the basin area (about 3km2). The morphology of the fan area is characterised by steep slopes (dip about 20%) and the fan apex is extended for 1.8 km inside the small catchment basin. This sedimentary fan was originated by a landslide that interested a part of a large deep-seated gravitational slope deformation, involving a wide area of about 55 km². The main controlling factor is tectonic and it is related to the proximity to regional fault systems and the consequent occurrence of fault weak rocks (GSI locally lower than 10 with compressive stress lower than 20MPa). Moreover, the fan deposit shows sedimentary evidences of recent debris flow events. The best current explanation of the Sernio fan involves an initial failure of some hundreds of Mm3. The run-out was quite limited because of the morphology of Valtellina’s valley floor, and the deposit filled the main valley forming a landslide dam, as confirmed by the lacustrine deposits detected upstream the fan. Nowadays the debris flow events represent the main hazard in the study area.

Keywords: anomalous sedimentary fans, deep seated gravitational slope deformation, Italy, rock avalanche

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15786 Design of Orientation-Free Handler and Fuzzy Controller for Wire-Driven Heavy Object Lifting System

Authors: Bo-Wei Song, Yun-Jung Lee

Abstract:

This paper presents an intention interface and controller for a wire-driven heavy object lifting system that assists the operator with moving a heavy object. The handler is designed to allow a comfortable working posture for the operator. Plus, as a human assistive system, the operator is involved in the control loop, where a fuzzy control system is used to consider the human control characteristics. The effectiveness and performance of the proposed system are proved by experiments.

Keywords: fuzzy controller, handler design, heavy object lifting system, human-assistive device, human-in-the-loop system

Procedia PDF Downloads 506
15785 CFD Analysis of Passive Cooling Building by Using Solar Chimney for Mild or Warm Climates

Authors: Naci Kalkan, Ihsan Dagtekin

Abstract:

This research presents the design and analysis of solar air-conditioning systems particularly solar chimney which is a passive strategy for natural ventilation, and demonstrates the structures of these systems’ using Computational Fluid Dynamic (CFD) and finally compares the results with several examples, which have been studied experimentally and carried out previously. In order to improve the performance of solar chimney system, highly efficient sub-system components are considered for the design. The general purpose of the research is to understand how efficiently solar chimney systems generate cooling, and is to improve the efficient of such systems for integration with existing and future domestic buildings.

Keywords: active and passive solar technologies, solar cooling system, solar chimney, natural ventilation, cavity depth, CFD models for solar chimney

Procedia PDF Downloads 564
15784 Association of Zinc with New Generation Cardiovascular Risk Markers in Childhood Obesity

Authors: Mustafa M. Donma, Orkide Donma

Abstract:

Zinc is a vital element required for growth and development. This fact makes zinc important, particularly for children. It maintains normal cellular structure and functions. This essential element appears to have protective effects against coronary artery disease and cardiomyopathy. Higher serum zinc levels are associated with lower risk of cardiovascular diseases (CVDs). There is a significant association between low serum zinc levels and heart failure. Zinc may be a potential biomarker of cardiovascular health. High sensitive cardiac troponin T (hs-cTnT) and cardiac myosin binding protein C (cMyBP-C) are new generation markers used for prediagnosis, diagnosis, and prognosis of CVDs. The aim of this study is to determine zinc as well as new generation cardiac markers profiles in children with normal body mass index (N-BMI), obese (OB), morbid obese (MO) children, and children with metabolic syndrome (MetS) findings. The association among them will also be investigated. Four study groups were constituted. The study protocol was approved by the institutional Ethics Committee of Tekirdag Namik Kemal University. Parents of the participants filled informed consent forms to participate in the study. Group 1 is composed of 44 children with N-BMI. Group 2 and Group 3 comprised 43 OB and 45 MO children, respectively. Forty-five MO children with MetS findings were included in Group 4. World Health Organization age- and sex-adjusted BMI percentile tables were used to constitute groups. These values were 15-85, 95-99, and above 99 for N-BMI, OB, and MO, respectively. Criteria for MetS findings were determined. Routine biochemical analyses, including zinc, were performed. High sensitive-cTnT and cMyBP-C concentrations were measured by kits based on enzyme-linked immunosorbent assay principle. Appropriate statistical tests within the scope of SPSS were used for the evaluation of the study data. p<0.05 was accepted as statistically significant. Four groups were matched for age and gender. Decreased zinc concentrations were measured in Groups 2, 3, and 4 compared to Group 1. Groups did not differ from one another in terms of hs-cTnT. There were statistically significant differences between cMyBP-C levels of MetS group and N-BMI as well as OB groups. There was an increasing trend going from N-BMI group to MetS group. There were statistically significant negative correlations between zinc and hs-cTnT as well as cMyBP-C concentrations in MetS group. In conclusion, inverse correlations detected between zinc and new generation cardiac markers (hs-TnT and cMyBP-C) have pointed out that decreased levels of this physiologically essential trace element accompany increased levels of hs-cTnT as well as cMyBP-C in children with MetS. This finding emphasizes that both zinc and these new generation cardiac markers may be evaluated as biomarkers of cardiovascular health during severe childhood obesity precipitated with MetS findings and also suggested as the messengers of the future risk in the adulthood periods of children with MetS.

Keywords: cardiac myosin binding protein-C, cardiovascular diseases, children, high sensitive cardiac troponin T, obesity

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15783 Ziegler Nichols Based Integral Proportional Controller for Superheated Steam Temperature Control System

Authors: Amil Daraz, Suheel Abdullah Malik, Tahir Saleem, Sajid Ali Bhati

Abstract:

In this paper, Integral Proportional (I-P) controller is employed for superheated steam temperature control system. The Ziegler-Nichols (Z-N) method is used for the tuning of I-P controller. The performance analysis of Z-N based I-P controller is assessed on superheated steam system of 500-MW boiler. The comparison of transient response parameters such as rise time, settling time, and overshoot is made with Z-N based Proportional Integral (PI) controller. It is observed from the results that Z-N based I-P controller completely eliminates the overshoot in the output response.

Keywords: superheated steam, process reaction curve, PI and I-P controller, Ziegler-Nichols Tuning

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15782 Numerical Study of Natural Convection of a Localized Heat Source at the up of a Nanofluid-Filled Enclosure

Authors: Marziyeh Heydari, Hossein Shokouhmand

Abstract:

This article presents a numerical study of natural convection of a heat source embedded on the up wall of an enclosure filled with nanofluid. The bottom and vertical walls of the enclosure are maintained at a relatively low temperature. The type of nanofluid and solid volume fraction of nanoparticle on the heat transfer performance is studied. The results indicated that adding nanoparticle into pure paraffin improves heat transfer. The results are presented over a wide range of Rayleigh numbers(Ra=〖10〗^3 〖-10〗^5), the volume fraction of nanoparticles (0≤ɸ≤0.4%). For an enclosure, the Nusselt number of a cu-paraffin nanofluid was reduced by increasing the volume fraction of nanoparticles above 0.2%.

Keywords: nanofluid, heat transfer, heat source, enclosure

Procedia PDF Downloads 308
15781 Developing of Ecological Internal Insulation Composite Boards for Innovative Retrofitting of Heritage Buildings

Authors: J. N. Nackler, K. Saleh Pascha, W. Winter

Abstract:

WHISCERS™ (Whole House In-Situ Carbon and Energy Reduction Solution) is an innovative process for Internal Wall Insulation (IWI) for energy-efficient retrofitting of heritage building, which uses laser measuring to determine the dimensions of a room, off-site insulation board cutting and rapid installation to complete the process. As part of a multinational investigation consortium the Austrian part adapted the WHISCERS system to local conditions of Vienna where most historical buildings have valuable stucco facades, precluding the application of an external insulation. The Austrian project contribution addresses the replacement of commonly used extruded polystyrene foam (XPS) with renewable materials such as wood and wood products to develop a more sustainable IWI system. As the timber industry is a major industry in Austria, a new innovative and more sustainable IWI solution could also open up new markets. The first approach of investigation was the Life Cycle Assessment (LCA) to define the performance of wood fibre board as insulation material in comparison to normally used XPS-boards. As one of the results the global-warming potential (GWP) of wood-fibre-board is 15 times less the equivalent to carbon dioxide while in the case of XPS it´s 72 times more. The hygrothermal simulation program WUFI was used to evaluate and simulate heat and moisture transport in multi-layer building components of the developed IWI solution. The results of the simulations prove in examined boundary conditions of selected representative brickwork constructions to be functional and usable without risk regarding vapour diffusion and liquid transport in proposed IWI. In a further stage three different solutions were developed and tested (1 - glued/mortared, 2 - with soft board, connected to wall with gypsum board as top layer, 3 - with soft board and clay board as top layer). All three solutions presents a flexible insulation layer out of wood fibre towards the existing wall, thus compensating irregularities of the wall surface. From first considerations at the beginning of the development phase, three different systems had been developed and optimized according to assembly technology and tested as small specimen in real object conditions. The built prototypes are monitored to detect performance and building physics problems and to validate the results of the computer simulation model. This paper illustrates the development and application of the Internal Wall Insulation system.

Keywords: internal insulation, wood fibre, hygrothermal simulations, monitoring, clay, condensate

Procedia PDF Downloads 213
15780 Relationship between Monthly Shrimp Catch Rates and the Oceanography-Related Variables

Authors: Hussain M. Al-foudari, Weizhong Chen, James M. Bishop

Abstract:

Correlations between oceanographic variables and monthly catch rates of total shrimp and those of each of the major species (Penaeus semisulcatus, Metapenaeus affinis and Parapenaeopsis stylifera) showed significant differences for particular conditions. Catches of P. semisulcatus were basically positively correlated with temperature, i.e., the higher the temperature, the higher the catch rate, while those of M. affinis and P. stylifera were negatively correlated with temperature, i.e., high catch rates occurred in the low temperature waters. Thus, during the months January and April, P. semisulcatus preferred waters with high temperature, usually the offshore and southern areas, while M. affinis and P. stylifera preferred waters with low temperature, usually inshore and northern areas. The relationships between the catch rate of P. semisulcatus and salinity were not so clear. Results indicated that although salinity was one of the factors affecting the distribution of P. semisulcatus, it was not the principal factor, and impacts from other variables, such as temperature, might overshadow the correlation between the catch rates of P. semisulcatus and salinity. The relationship between shrimp catch rates and dissolved oxygen (DO) also showed mixed results. The catch rates of M. affinis increased with a decrease of surface DO in November 2013, but decreased with lower bottom DO in December. These results indicated that DO might be a factor affecting distributions of the shrimp; however; the true correlation between catch rate and DO might be easily overshadowed by other environmental variables. Catch rates of P. semisulcatus did not show any relationship with depth. P. semisulcatus is a migratory species and widely distributed in Kuwait's waters.During the shrimp season from July through December, P. semisulcatus occurs in almost all areas in Kuwait's waters irrespective of water depth. The catch rates of M. affinis and P. stylifera, however, showed clear relationships with depth. Both species had significantly higher catch rates in shallower waters, indicative of their restricted distribution.

Keywords: Kuwait, Penaeus semisulcatus, Metapenaeus affinis, Parapenaeopsis stylifera, Arabian gulf

Procedia PDF Downloads 483
15779 Design of an Augmented Automatic Choosing Control with Constrained Input by Lyapunov Functions Using Gradient Optimization Automatic Choosing Functions

Authors: Toshinori Nawata

Abstract:

In this paper a nonlinear feedback control called augmented automatic choosing control (AACC) for a class of nonlinear systems with constrained input is presented. When designing the control, a constant term which arises from linearization of a given nonlinear system is treated as a coefficient of a stable zero dynamics. Parameters of the control are suboptimally selected by maximizing the stable region in the sense of Lyapunov with the aid of a genetic algorithm. This approach is applied to a field excitation control problem of power system to demonstrate the splendidness of the AACC. Simulation results show that the new controller can improve performance remarkably well.

Keywords: augmented automatic choosing control, nonlinear control, genetic algorithm, zero dynamics

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15778 Supply Chain Improvement of the Halal Goat Industry in the Autonomous Region in Muslim Mindanao

Authors: Josephine R. Migalbin

Abstract:

Halal is an Arabic word meaning "lawful" or "permitted". When it comes to food and consumables, Halal is the dietary standard of Muslims. The Autonomous Region in Muslim Mindanao (ARMM) has a comparative advantage when it comes to Halal Industry because it is the only Muslim region in the Philippines and the natural starting point for the establishment of a halal industry in the country. The region has identified goat production not only for domestic consumption but for export market. Goat production is one of its strengths due to cultural compatibility. There is a high demand for goats during Ramadhan and Eid ul-Adha. The study aimed to provide an overview of the ARMM Halal Goat Industry; to map out the specific supply chain of halal goat, and to analyze the performance of the halal goat supply chain in terms of efficiency, flexibility, and overall responsiveness. It also aimed to identify areas for improvement in the supply chain such as behavioural, institutional, and process to provide recommendations for improvement in the supply chain towards efficient and effective production and marketing of halal goats, subsequently improving the plight of the actors in the supply chain. Generally, the raising of goats is characterized by backyard production (92.02%). There are four interrelated factors affecting significantly the production of goats which are breeding prolificacy, prevalence of diseases, feed abundance and pre-weaning mortality rate. The institutional buyers are mostly traders, restaurants/eateries, supermarkets, and meat shops, among others. The municipalities of Midsayap and Pikit in another region and Parang are the major goat sources and the municipalities in ARMM among others. In addition to the major supply centers, Siquijor, an island province in the Visayas is becoming a key source of goats. Goats are usually gathered by traders/middlemen and brought to the public markets. Meat vendors purchase them directly from raisers, slaughtered and sold fresh in wet markets. It was observed that there is increased demand at 2%/year and that supply is not enough to meet the demand. Farm gate price is 2.04 USD to 2.11 USD/kg liveweight. Industry information is shared by three key participants - raisers, traders and buyers. All respondents reported that information is through personal built-upon past experiences and that there is no full disclosure of information among the key participants in the chain. The information flow in the industry is fragmented in nature such that no total industry picture exists. In the last five years, numerous local and foreign agencies had undertaken several initiatives for the development of the halal goat industry in ARMM. The major issues include productivity which is the greatest challenge, difficulties in accessing technical support channels and lack of market linkage and consolidation. To address the various issues and concerns of the various industry players, there is a need to intensify appropriate technology transfer through extension activities, improve marketing channels by grouping producers, strengthen veterinary services and provide capital windows to improve facilities and reduce logistics and transaction costs in the entire supply chain.

Keywords: autonomous region in Muslim Mindanao, halal, halal goat industry, supply chain improvement

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15777 Artificial Neural Networks for Cognitive Radio Network: A Survey

Authors: Vishnu Pratap Singh Kirar

Abstract:

The main aim of the communication system is to achieve maximum performance. In cognitive radio, any user or transceiver have the ability to sense best suitable channel, while the channel is not in use. It means an unlicensed user can share the spectrum of licensed user without any interference. Though the spectrum sensing consumes a large amount of energy and it can reduce by applying various artificial intelligent methods for determining proper spectrum holes. It also increases the efficiency of Cognitive Radio Network (CRN). In this survey paper, we discuss the use of different learning models and implementation of Artificial Neural Network (ANN) to increase the learning and decision-making capacity of CRN without affecting bandwidth, cost and signal rate.

Keywords: artificial neural network, cognitive radio, cognitive radio networks, back propagation, spectrum sensing

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15776 2.4 GHz 0.13µM Multi Biased Cascode Power Amplifier for ISM Band Wireless Applications

Authors: Udayan Patankar, Shashwati Bhagat, Vilas Nitneware, Ants Koel

Abstract:

An ISM band power amplifier is a type of electronic amplifier used to convert a low-power radio-frequency signal into a larger signal of significant power, typically used for driving the antenna of a transmitter. Due to drastic changes in telecommunication generations may lead to the requirements of improvements. Rapid changes in communication lead to the wide implementation of WLAN technology for its excellent characteristics, such as high transmission speed, long communication distance, and high reliability. Many applications such as WLAN, Bluetooth, and ZigBee, etc. were evolved with 2.4GHz to 5 GHz ISM Band, in which the power amplifier (PA) is a key building block of RF transmitters. There are many manufacturing processes available to manufacture a power amplifier for desired power output, but the major problem they have faced is about the power it consumed for its proper working, as many of them are fabricated on the GaN HEMT, Bi COMS process. In this paper we present a CMOS Base two stage cascode design of power amplifier working on 2.4GHz ISM frequency band. To lower the costs and allow full integration of a complete System-on-Chip (SoC) we have chosen 0.13µm low power CMOS technology for design. While designing a power amplifier, it is a real task to achieve higher power efficiency with minimum resources. This design showcase the Multi biased Cascode methodology to implement a two-stage CMOS power amplifier using ADS and LTSpice simulating tool. Main source is maximum of 2.4V which is internally distributed into different biasing point VB driving and VB driven as required for distinct stages of two stage RF power amplifier. It shows maximum power added efficiency near about 70.195% whereas its Power added efficiency calculated at 1 dB compression point is 44.669 %. Biased MOSFET is used to reduce total dc current as this circuit is designed for different wireless applications comes under 2.4GHz ISM Band.

Keywords: RFIC, PAE, RF CMOS, impedance matching

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15775 MOF [(4,4-Bipyridine)₂(O₂CCH₃)₂Zn]N as Heterogeneous Acid Catalysts for the Transesterification of Canola Oil

Authors: H. Arceo, S. Rincon, C. Ben-Youssef, J. Rivera, A. Zepeda

Abstract:

Biodiesel has emerged as a material with great potential as a renewable energy replacement to current petroleum-based diesel. Recently, biodiesel production is focused on the development of more efficient, sustainable process with lower costs of production. In this sense, a “green” approach to biodiesel production has stimulated the use of sustainable heterogeneous acid catalysts, that are better alternatives to conventional processes because of their simplicity and the simultaneous promotion of esterification and transesterification reactions from low-grade, highly-acidic and water containing oils without the formation of soap. The focus of this methodology is the development of new heterogeneous catalysts that under ordinary reaction conditions could reach yields similar to homogeneous catalysis. In recent years, metal organic frameworks (MOF) have attracted much interest for their potential as heterogeneous acid catalysts. They are crystalline porous solids formed by association of transition metal ions or metal–oxo clusters and polydentate organic ligands. This hybridization confers MOFs unique features such as high thermal stability, larger pore size, high specific area, high selectivity and recycling potential. Thus, MOF application could be a way to improve the biodiesel production processes. In this work, we evaluated the catalytic activity of MOF [(4,4-bipyridine)2(O₂CCH₃)2Zn]n (MOF Zn-I) for the synthesis of biodiesel from canola oil. The reaction conditions were optimized using the response surface methodology with a compound design central with 24. The variables studied were: Reaction temperature, amount of catalyst, molar ratio oil: MetOH and reaction time. The preparation MOF Zn-I was performed by mixing 5 mmol 4´4 dipyridine dissolved in 25 mL methanol with 10 mmol Zn(O₂CCH₃)₂ ∙ 2H₂O in 25 mL water. The crystals were obtained by slow evaporation of the solvents at 60°C for 18 h. The prepared catalyst was characterized using X-ray diffraction (XRD) and Fourier transform infrared spectrometer (FT-IR). The prepared catalyst was characterized using X-ray diffraction (XRD) and Fourier transform infrared spectrometer (FT-IR). Experiments were performed using commercially available canola oil in ace pressure tube under continuous stirring. The reaction was filtered and vacuum distilled to remove the catalyst and excess alcohol, after which it was centrifuged to separate the obtained biodiesel and glycerol. 1H NMR was used to calculate the process yield. GC-MS was used to quantify the fatty acid methyl ester (FAME). The results of this study show that the acid catalyst MOF Zn-I could be used as catalyst for biodiesel production through heterogeneous transesterification of canola oil with FAME yield 82 %. The optimum operating condition for the catalytic reaction were of 142°C, 0.5% catalyst/oil weight ratio, 1:30 oil:MeOH molar ratio and 5 h reaction time.

Keywords: fatty acid methyl ester, heterogeneous acid catalyst, metal organic framework, transesterification

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15774 Low-Complexity Multiplication Using Complement and Signed-Digit Recoding Methods

Authors: Te-Jen Chang, I-Hui Pan, Ping-Sheng Huang, Shan-Jen Cheng

Abstract:

In this paper, a fast multiplication computing method utilizing the complement representation method and canonical recoding technique is proposed. By performing complements and canonical recoding technique, the number of partial products can be reduced. Based on these techniques, we propose an algorithm that provides an efficient multiplication method. On average, our proposed algorithm is to reduce the number of k-bit additions from (0.25k+logk/k+2.5) to (k/6 +logk/k+2.5), where k is the bit-length of the multiplicand A and multiplier B. We can therefore efficiently speed up the overall performance of the multiplication. Moreover, if we use the new proposes to compute common-multiplicand multiplication, the computational complexity can be reduced from (0.5 k+2 logk/k+5) to (k/3+2 logk/k+5) k-bit additions.

Keywords: algorithm design, complexity analysis, canonical recoding, public key cryptography, common-multiplicand multiplication

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15773 Hydroxyapatite Nanorods as Novel Fillers for Improving the Properties of PBSu

Authors: M. Nerantzaki, I. Koliakou, D. Bikiaris

Abstract:

This study evaluates the hypothesis that the incorporation of fibrous hydroxyapatite nanoparticles (nHA) with high crystallinity and high aspect ratio, synthesized by hydrothermal method, into Poly(butylene succinate) (PBSu), improves the bioactivity of the aliphatic polyester and affects new bone growth inhibiting resorption and enhancing bone formation. Hydroxyapatite nanorods were synthesized using a simple hydrothermal procedure. First, the HPO42- -containing solution was added drop-wise into the Ca2+-containing solution, while the molar ratio of Ca/P was adjusted at 1.67. The HA precursor was then treated hydrothermally at 200°C for 72 h. The resulting powder was characterized using XRD, FT-IR, TEM, and EDXA. Afterwards, PBSu nanocomposites containing 2.5wt% (nHA) were prepared by in situ polymerization technique for the first time and were examined as potential scaffolds for bone engineering applications. For comparison purposes composites containing either 2.5wt% micro-Bioglass (mBG) or 2.5wt% mBG-nHA were prepared and studied, too. The composite scaffolds were characterized using SEM, FTIR, and XRD. Mechanical testing (Instron 3344) and Contact Angle measurements were also carried out. Enzymatic degradation was studied in an aqueous solution containing a mixture of R. Oryzae and P. Cepacia lipases at 37°C and pH=7.2. In vitro biomineralization test was performed by immersing all samples in simulated body fluid (SBF) for 21 days. Biocompatibility was assessed using rat Adipose Stem Cells (rASCs), genetically modified by nucleofection with DNA encoding SB100x transposase and pT2-Venus-neo transposon expression plasmids in order to attain fluorescence images. Cell proliferation and viability of cells on the scaffolds were evaluated using fluoresce microscopy and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay. Finally, osteogenic differentiation was assessed by staining rASCs with alizarine red using cetylpyridinium chloride (CPC) method. TEM image of the fibrous HAp nanoparticles, synthesized in the present study clearly showed the fibrous morphology of the synthesized powder. The addition of nHA decreased significantly the contact angle of the samples, indicating that the materials become more hydrophilic and hence they absorb more water and subsequently degrade more rapidly. In vitro biomineralization test confirmed that all samples were bioactive as mineral deposits were detected by X-ray diffractometry after incubation in SBF. Metabolic activity of rASCs on all PBSu composites was high and increased from day 1 of culture to day 14. On day 28 metabolic activity of rASCs cultured on samples enriched with bioceramics was significantly decreased due to possible differentiation of rASCs to osteoblasts. Staining rASCs with alizarin red after 28 days in culture confirmed our initial hypothesis as the presence of calcium was detected, suggesting osteogenic differentiation of rACS on PBSu/nHAp/mBG 2.5% and PBSu/mBG 2.5% composite scaffolds.

Keywords: biomaterials, hydroxyapatite nanorods, poly(butylene succinate), scaffolds

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15772 Access Control System for Big Data Application

Authors: Winfred Okoe Addy, Jean Jacques Dominique Beraud

Abstract:

Access control systems (ACs) are some of the most important components in safety areas. Inaccuracies of regulatory frameworks make personal policies and remedies more appropriate than standard models or protocols. This problem is exacerbated by the increasing complexity of software, such as integrated Big Data (BD) software for controlling large volumes of encrypted data and resources embedded in a dedicated BD production system. This paper proposes a general access control strategy system for the diffusion of Big Data domains since it is crucial to secure the data provided to data consumers (DC). We presented a general access control circulation strategy for the Big Data domain by describing the benefit of using designated access control for BD units and performance and taking into consideration the need for BD and AC system. We then presented a generic of Big Data access control system to improve the dissemination of Big Data.

Keywords: access control, security, Big Data, domain

Procedia PDF Downloads 129
15771 Electrochemical Corrosion of Steels in Distillery Effluent

Authors: A. K. Singh, Chhotu Ram

Abstract:

The present work relates to the corrosivity of distillery effluent and corrosion performance of mild steel and stainless steels SS304L, SS316L, and 2205. The report presents the results and conclusions drawn on the basis of (i) electrochemical polarization tests performed in distillery effluent and laboratory prepared solutions having composition similar to that of the effluent (ii) the surface examination by scanning electron microscope (SEM) of the corroded steel samples. It is observed that pH and presence of chloride, phosphate, calcium, nitrite and nitrate in distillery effluent enhance corrosion, whereas presence of sulphate and potassium inhibits corrosion. Among the materials tested, mild steel is observed to experience maximum corrosion followed by stainless steels SS304L, SS316L, and 2205.

Keywords: corrosion, distillery effluent, electrochemical polarization, steel

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15770 Intraspecific Biochemical Diversity of Dalmatian Pyrethrum Across the Different Bioclimatic Regions of Its Natural Distribution Area

Authors: Martina Grdiša, Filip Varga, Nina Jeran, Ante Turudić, Zlatko Šatović

Abstract:

Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.) is a plant species that occurs naturally in the eastern Mediterranean. It is of immense economic importance as it synthesizes and accumulates the phytochemical compound pyrethrin. Pyrethrin consists of several monoterpene esters (pyrethrin I and II, cinerin I and II and jasmolin I and II), which have insecticidal and repellent activity through their synergistic action. In this study, 15 natural Dalmatian pyrethrum populations were sampled along their natural range in Croatia, Bosnia and Herzegovina and Montenegro to characterize and compare their pyrethrin profiles and to define the bioclimatic factors associated with the accumulation of each pyrethrin compound. Pyrethrins were extracted from the dried flower heads of Dalmatian pyrethrum using ultrasound-assisted extraction and the amount of each compound was quantified using high-performance liquid chromatography coupled to DAD-UV /VIS. The biochemical data were subjected to analysis of variance, correlation analysis and multivariate analysis. Quantitative variability within and among populations was found, with population P15 Vranjske Njive, Podgorica having the significantly highest pyrethrin I content (66.47% of total pyrethrin content), while the highest levels of total pyrethrin were found in P14 Budva (1.27% of dry flower weight; DW), followed by P08 Korčula (1.15% DW). Based on the environmental conditions at the sampling sites of the populations, five bioclimatic groups were distinguished, referred to as A, B, C, D, and E, each with rare chemical profile. The first group (A) consisted of the northern Adriatic population P01 Vrbnik, Krk and the population P06 Sevid - the coastal population of the central Adriatic, and generally differed significantly from the other bioclimatic groups by higher average jasmolin II values (2.13% of total pyrethrin). The second group (B) consisted of two central Adriatic island populations (P02 Telašćica, Dugi otok and P03 Žman, Dugi otok), while the remaining central Adriatic island populations were grouped in bioclimatic group C, which was characterized by the significantly highest average pyrethrin II (48.52% of total pyrethrin) and cinerin II (5.31% DW) content. The South Adriatic inland populations P10 Srđ and P11 Trebinje (Bosnia and Herzegovina), and the populations from Montenegro (P12 Grahovo, P13 Lovćen, P14 Budva and P15 Vranjske Njive, Podgorica) formed bioclimatic group E. This bioclimatic group was characterized by the highest average values for pyrethrin I (53.07 % of total pyrethrin), total pyrethrin content (1.06 % DW) and the ratio of pyrethrin I and II (1.85). Slightly lower values (although not significant) for the latter traits were detected in bioclimatic group D (southern Adriatic island populations P07 Vis, P08 Korčula and P09 Mljet). A weak but significant correlation was found between the levels of some pyrethrin compounds and bioclimatic variables (e.g., BIO03 Isothermality and BIO04 Temperature Seasonality), which explains part of the variability observed in the populations studied. This suggests the interconnection between bioclimatic variables and biochemical profiles either through the selection of adapted genotypes or through the ability of species to alter the expression of biochemical traits in response to environmental changes.

Keywords: biopesticides, biochemical variability, pyrethrin, Tanacetum cinerariifolium

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15769 Measuring Ecological Footprint: Life Cycle Assessment Approach

Authors: Binita Shah, Seema Unnikrishnan

Abstract:

In the recent time, an increasing interest in the analysis and efforts to reduce the environmental impacts generated by man-made activities has been seen widely being discussed and implemented by the society. The industrial processes are expressing their concern and showing keen interest in redesigning and amending the operation process leading to better environmental performance by upgrading technologies and adjusting the financial inputs. There are various tools available for the assessment of process and production of goods on the environment. Most methods look at a particular impact on the ecosystem. Life Cycle Assessment (LCA) is one of the most widely accepted and scientifically founded methodologies to assess the overall environmental impacts of products and processes. This paper looks at the tools used in India for environmental impact assessment.

Keywords: life cycle assessment, ecological footprint, measuring sustainability, India

Procedia PDF Downloads 642
15768 Transient Heat Transfer: Experimental Investigation near the Critical Point

Authors: Andreas Kohlhepp, Gerrit Schatte, Wieland Christoph, Spliethoff Hartmut

Abstract:

In recent years the research of heat transfer phenomena of water and other working fluids near the critical point experiences a growing interest for power engineering applications. To match the highly volatile characteristics of renewable energies, conventional power plants need to shift towards flexible operation. This requires speeding up the load change dynamics of steam generators and their heating surfaces near the critical point. In dynamic load transients, both a high heat flux with an unfavorable ratio to the mass flux and a high difference in fluid and wall temperatures, may cause problems. It may lead to deteriorated heat transfer (at supercritical pressures), dry-out or departure from nucleate boiling (at subcritical pressures), all cases leading to an extensive rise of temperatures. For relevant technical applications, the heat transfer coefficients need to be predicted correctly in case of transient scenarios to prevent damage to the heated surfaces (membrane walls, tube bundles or fuel rods). In transient processes, the state of the art method of calculating the heat transfer coefficients is using a multitude of different steady-state correlations for the momentarily existing local parameters for each time step. This approach does not necessarily reflect the different cases that may lead to a significant variation of the heat transfer coefficients and shows gaps in the individual ranges of validity. An algorithm was implemented to calculate the transient behavior of steam generators during load changes. It is used to assess existing correlations for transient heat transfer calculations. It is also desirable to validate the calculation using experimental data. By the use of a new full-scale supercritical thermo-hydraulic test rig, experimental data is obtained to describe the transient phenomena under dynamic boundary conditions as mentioned above and to serve for validation of transient steam generator calculations. Aiming to improve correlations for the prediction of the onset of deteriorated heat transfer in both, stationary and transient cases the test rig was specially designed for this task. It is a closed loop design with a directly electrically heated evaporation tube, the total heating power of the evaporator tube and the preheater is 1MW. To allow a big range of parameters, including supercritical pressures, the maximum pressure rating is 380 bar. The measurements contain the most important extrinsic thermo-hydraulic parameters. Moreover, a high geometric resolution allows to accurately predict the local heat transfer coefficients and fluid enthalpies.

Keywords: departure from nucleate boiling, deteriorated heat transfer, dryout, supercritical working fluid, transient operation of steam generators

Procedia PDF Downloads 217
15767 Cortex-M3 Based Virtual Platform Implementation for Software Development

Authors: Jun Young Moon, Hyeonggeon Lee, Jong Tae Kim

Abstract:

In this paper, we present Cortex-M3 based virtual platform which can virtualize wearable hardware platform and evaluate hardware performance. Cortex-M3 is very popular microcontroller in wearable devices, hardware sensors and display devices. This platform can be used to implement software layer for specific hardware architecture. By using the proposed platform the software development process can be parallelized with hardware development process. We present internal mechanism to implement the proposed virtual platform and describe how to use the proposed platform to develop software by using case study which is low cost wearable device that uses Cortex-M3.

Keywords: electronic system level design, software development, virtual platform, wearable device

Procedia PDF Downloads 368
15766 Performance Shortfalls and Corporate Recidivism: A Contingency Approach

Authors: Kepeng Li

Abstract:

This paper examines the phenomenon of recidivism in the Chinese stock market, emphasizing the significance of mitigating repeat offences within the corporate domain. Using a contingency model and data from Chinese publicly listed companies (1999-2018), the study investigates the impact of underperformance, governance factors, and managerial traits on unethical conduct. The research suggests that persistently unmet economic objectives can foster problem-focused exploration, potentially leading to misconduct. Furthermore, the study considers the unique cultural context of China, where “guanxi” and corruption may influence corporate behavior. It concludes that governance mechanisms play a pivotal role in regulating corporate behavior, underscoring the necessity for enhanced oversight and enforcement of corporate governance standards.

Keywords: recidivism, corporate misbehavior, BTOF, aspiration level, corporate governance, individual characteristics

Procedia PDF Downloads 95
15765 The Role of Metaheuristic Approaches in Engineering Problems

Authors: Ferzat Anka

Abstract:

Many types of problems can be solved using traditional analytical methods. However, these methods take a long time and cause inefficient use of resources. In particular, different approaches may be required in solving complex and global engineering problems that we frequently encounter in real life. The bigger and more complex a problem, the harder it is to solve. Such problems are called Nondeterministic Polynomial time (NP-hard) in the literature. The main reasons for recommending different metaheuristic algorithms for various problems are the use of simple concepts, the use of simple mathematical equations and structures, the use of non-derivative mechanisms, the avoidance of local optima, and their fast convergence. They are also flexible, as they can be applied to different problems without very specific modifications. Thanks to these features, it can be easily embedded even in many hardware devices. Accordingly, this approach can also be used in trend application areas such as IoT, big data, and parallel structures. Indeed, the metaheuristic approaches are algorithms that return near-optimal results for solving large-scale optimization problems. This study is focused on the new metaheuristic method that has been merged with the chaotic approach. It is based on the chaos theorem and helps relevant algorithms to improve the diversity of the population and fast convergence. This approach is based on Chimp Optimization Algorithm (ChOA), that is a recently introduced metaheuristic algorithm inspired by nature. This algorithm identified four types of chimpanzee groups: attacker, barrier, chaser, and driver, and proposed a suitable mathematical model for them based on the various intelligence and sexual motivations of chimpanzees. However, this algorithm is not more successful in the convergence rate and escaping of the local optimum trap in solving high-dimensional problems. Although it and some of its variants use some strategies to overcome these problems, it is observed that it is not sufficient. Therefore, in this study, a newly expanded variant is described. In the algorithm called Ex-ChOA, hybrid models are proposed for position updates of search agents, and a dynamic switching mechanism is provided for transition phases. This flexible structure solves the slow convergence problem of ChOA and improves its accuracy in multidimensional problems. Therefore, it tries to achieve success in solving global, complex, and constrained problems. The main contribution of this study is 1) It improves the accuracy and solves the slow convergence problem of the ChOA. 2) It proposes new hybrid movement strategy models for position updates of search agents. 3) It provides success in solving global, complex, and constrained problems. 4) It provides a dynamic switching mechanism between phases. The performance of the Ex-ChOA algorithm is analyzed on a total of 8 benchmark functions, as well as a total of 2 classical and constrained engineering problems. The proposed algorithm is compared with the ChoA, and several well-known variants (Weighted-ChoA, Enhanced-ChoA) are used. In addition, an Improved algorithm from the Grey Wolf Optimizer (I-GWO) method is chosen for comparison since the working model is similar. The obtained results depict that the proposed algorithm performs better or equivalently to the compared algorithms.

Keywords: optimization, metaheuristic, chimp optimization algorithm, engineering constrained problems

Procedia PDF Downloads 70
15764 Low-Cost Wireless Power Transfer System for Smart Recycling Containers

Authors: Juan Luis Leal, Rafael Maestre, Ovidio López

Abstract:

As innovation progresses, more possibilities are made available to increase the efficiency and reach of solutions for Smart Cities, most of which require the data provided by the Internet of Things (IoT) devices and may even have higher power requirements such as motors or actuators. A reliable power supply with the lowest maintenance is a requirement for the success of these solutions in the long term. Energy harvesting, mainly solar, becomes the solution of choice in most cases, but only if there is enough power to be harvested, which may depend on the device location (e.g., outdoors vs. indoor). This is the case of Smart Waste Containers with compaction systems, which have moderately high-power requirements, and may be installed in places with little sunlight for solar generation. It should be noted that waste is unloaded from the containers with cranes, so sudden and irregular movements may happen, making wired power unviable. In these cases, a wireless power supply may be a great alternative. This paper proposes a cost-effective two coil resonant wireless power transfer (WPT) system and describes its implementation, which has been carried out within an R&D project and validated in real settings with smart containers. Experimental results prove that the developed system achieves wireless power transmission up to 35W in the range of 5 cm to 1 m with a peak efficiency of 78%. The circuit is operated at relatively low resonant frequencies, which combined with enough wire-to-wire separation between the coil windings, reduce the losses caused by the proximity effect and, therefore, allow the use of common stranded wire instead of Litz wire, this without reducing the efficiency significantly. All these design considerations led to a final system that achieves a high efficiency for the desired charging range, simplifying the energy supply for Smart Containers as well as other devices that may benefit from a cost-effective wireless charging system.

Keywords: electromagnetic coupling, resonant wireless charging, smart recycling containers, wireless power transfer

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15763 Integration of EEG and Motion Tracking Sensors for Objective Measure of Attention-Deficit Hyperactivity Disorder in Pre-Schoolers

Authors: Neha Bhattacharyya, Soumendra Singh, Amrita Banerjee, Ria Ghosh, Oindrila Sinha, Nairit Das, Rajkumar Gayen, Somya Subhra Pal, Sahely Ganguly, Tanmoy Dasgupta, Tanusree Dasgupta, Pulak Mondal, Aniruddha Adhikari, Sharmila Sarkar, Debasish Bhattacharyya, Asim Kumar Mallick, Om Prakash Singh, Samir Kumar Pal

Abstract:

Background: We aim to develop an integrated device comprised of single-probe EEG and CCD-based motion sensors for a more objective measure of Attention-deficit Hyperactivity Disorder (ADHD). While the integrated device (MAHD) relies on the EEG signal (spectral density of beta wave) for the assessment of attention during a given structured task (painting three segments of a circle using three different colors, namely red, green and blue), the CCD sensor depicts movement pattern of the subjects engaged in a continuous performance task (CPT). A statistical analysis of the attention and movement patterns was performed, and the accuracy of the completed tasks was analysed using indigenously developed software. The device with the embedded software, called MAHD, is intended to improve certainty with criterion E (i.e. whether symptoms are better explained by another condition). Methods: We have used the EEG signal from a single-channel dry sensor placed on the frontal lobe of the head of the subjects (3-5 years old pre-schoolers). During the painting of three segments of a circle using three distinct colors (red, green, and blue), absolute power for delta and beta EEG waves from the subjects are found to be correlated with relaxation and attention/cognitive load conditions. While the relaxation condition of the subject hints at hyperactivity, a more direct CCD-based motion sensor is used to track the physical movement of the subject engaged in a continuous performance task (CPT) i.e., separation of the various colored balls from one table to another. We have used our indigenously developed software for the statistical analysis to derive a scale for the objective assessment of ADHD. We have also compared our scale with clinical ADHD evaluation. Results: In a limited clinical trial with preliminary statistical analysis, we have found a significant correlation between the objective assessment of the ADHD subjects with that of the clinician’s conventional evaluation. Conclusion: MAHD, the integrated device, is supposed to be an auxiliary tool to improve the accuracy of ADHD diagnosis by supporting greater criterion E certainty.

Keywords: ADHD, CPT, EEG signal, motion sensor, psychometric test

Procedia PDF Downloads 92