Search results for: conventional food production
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12795

Search results for: conventional food production

7845 Complex Event Processing System Based on the Extended ECA Rule

Authors: Kwan Hee Han, Jun Woo Lee, Sung Moon Bae, Twae Kyung Park

Abstract:

ECA (Event-Condition-Action) languages are largely adopted for event processing since they are an intuitive and powerful paradigm for programming reactive systems. However, there are some limitations about ECA rules for processing of complex events such as coupling of event producer and consumer. The objective of this paper is to propose an ECA rule pattern to improve the current limitations of ECA rule, and to develop a prototype system. In this paper, conventional ECA rule is separated into 3 parts and each part is extended to meet the requirements of CEP. Finally, event processing logic is established by combining the relevant elements of 3 parts. The usability of proposed extended ECA rule is validated by a test scenario in this study.

Keywords: complex event processing, ECA rule, Event processing system, event-driven architecture, internet of things

Procedia PDF Downloads 519
7844 The Influence of Absorptive Capacity on Process Innovation: An Exploratory Study in Seven Leading and Emerging Countries

Authors: Raphael M. Rettig, Tessa C. Flatten

Abstract:

This empirical study answer calls for research on Absorptive Capacity and Process Innovation. Due to the fourth industrial revolution, manufacturing companies face the biggest disruption of their production processes since the rise of advanced manufacturing technologies in the last century. Therefore, process innovation will become a critical task to master in the future for many manufacturing firms around the world. The general ability of organizations to acquire, assimilate, transform, and exploit external knowledge, known as Absorptive Capacity, was proven to positively influence product innovation and is already conceptually associated with process innovation. The presented research provides empirical evidence for this influence. The findings are based on an empirical analysis of 732 companies from seven leading and emerging countries: Brazil, China, France, Germany, India, Japan, and the United States of America. The answers to the survey were collected in February and March 2018 and addressed senior- and top-level management with a focus on operations departments. The statistical analysis reveals the positive influence of potential and Realized Absorptive Capacity on successful process innovation taking the implementation of new digital manufacturing processes as an example. Potential Absorptive Capacity covering the acquisition and assimilation capabilities of an organization showed a significant positive influence (β = .304, p < .05) on digital manufacturing implementation success and therefore on process innovation. Realized Absorptive Capacity proved to have significant positive influence on process innovation as well (β = .461, p < .01). The presented study builds on prior conceptual work in the field of Absorptive Capacity and process innovation and contributes theoretically to ongoing research in two dimensions. First, the already conceptually associated influence of Absorptive Capacity on process innovation is backed by empirical evidence in a broad international context. Second, since Absorptive Capacity was measured with a focus on new product development, prior empirical research on Absorptive Capacity was tailored to the research and development departments of organizations. The results of this study highlight the importance of Absorptive Capacity as a capability in mechanical engineering and operations departments of organizations. The findings give managers an indication of the importance of implementing new innovative processes into their production system and fostering the right mindset of employees to identify new external knowledge. Through the ability to transform and exploit external knowledge, own production processes can be innovated successfully and therefore have a positive influence on firm performance and the competitive position of their organizations.

Keywords: absorptive capacity, digital manufacturing, dynamic capabilities, process innovation

Procedia PDF Downloads 134
7843 Role of Self-Concept in the Relationship between Emotional Abuse and Mental Health of Employees in the North West Province, South Africa

Authors: L. Matlawe, E. S. Idemudia

Abstract:

The stability is an important topic to plan and manage the energy in the microgrids as the same as the conventional power systems. The voltage and frequency stability is one of the most important issues recently studied in microgrids. The objectives of this paper are the modeling and designing of the components and optimal controllers for the voltage and frequency control of the AC/DC hybrid microgrid under the different disturbances. Since the PI controllers have the advantages of simple structure and easy implementation, so they were designed and modeled in this paper. The harmony search (HS) algorithm is used to optimize the controllers’ parameters. According to the achieved results, the PI controllers have a good performance in voltage and frequency control of the microgrid.

Keywords: emotional abuse, employees, mental health, self-concept

Procedia PDF Downloads 238
7842 Assessment of Forage Utilization for Pasture-Based Livestock Production in Udubo Grazing Reserve, Bauchi State

Authors: Mustapha Saidu, Bilyaminu Mohammed

Abstract:

The study was conducted in Udubo Grazing Reserve between July 2019 and October 2019 to assess forage utilization for pasture-based livestock production in reserve. The grazing land was cross-divided into grids, where 15 coordinates were selected as the sample points. Grids of one-kilometer interval were made. The grids were systematically selected 1 grid after 7 grids. 1 × 1-meter quadrat was made at the coordinate of the selected grids for measurement, estimation, and sample collection. The results of the study indicated that Zornia glochidiatah has the highest percent of species composition (42%), while Mitracarpus hirtus has the lowest percent (0.1%). Urochloa mosambicensis has 48 percent of height removed and 27 percent used by weight, Zornia glochidiata 60 percent of height removed and 57 percent used by weight, Alysicapus veginalis has 55 percent of height removed, and 40 percent used by weight, and Cenchrus biflorus has 40 percent of height removed and 28 percent used by weight. The target is 50 percent utilization of forage by weight during a grazing period as well as at the end of the grazing season. The study found that Orochloa mosambicensis, Alysicarpus veginalis, and Cenchrus biflorus had lower percent by weight which is normal, while Zornia glochidiata had a higher percent by weight which is an indication of danger. The study recommends that the identification of key plant species in pasture and rangeland is critical to implementing a successful grazing management plan. There should be collective action and promotion of historically generated grazing knowledge through public and private advocacies.

Keywords: forage, grazing reserve, live stock, pasture, plant species

Procedia PDF Downloads 70
7841 Development of Electromyography (EMG) Signal Acquisition System by Simple Electronic Circuits

Authors: Divya Pradip Roy, Md. Zahirul Alam Chowdhury

Abstract:

Electromyography (EMG) sensors are generally used to record the electrical activity produced by skeletal muscles. The conventional EMG sensors available in the market are expensive. This research suggests a low cost EMG sensor design which can be built with simple devices within our reach. In this research, one instrumentation amplifier, two high pass filters, two low pass filters and an inverting amplifier is connected sequentially. The output from the circuit exhibits electrical potential generated by the muscle cells when they are neurologically activated. This electromyography signal is used to control prosthetic devices, identifying neuromuscular diseases and for various other purposes.

Keywords: EMG, high pass filter, instrumentation amplifier, inverting amplifier, low pass filter, neuromuscular

Procedia PDF Downloads 159
7840 The Production of Collagen and Collagen Peptides from Nile Tilapia Skin Using Membrane Technology

Authors: M. Thuanthong, W. Youravong, N. Sirinupong

Abstract:

Nile tilapia (Oreochromis niloticus) is one of fish species cultured in Thailand with a high production volume. A lot of skin is generated during fish processing. In addition, there are many research reported that fish skin contains abundant of collagen. Thus, the use of Nile tilapia skin as collagen source can increase the benefit of industrial waste. In this study, Acid soluble collagen (ASC) was extracted at 5, 15 or 25 ˚C with 0.5 M acetic acid then the acid was removed out and collagen was concentrated by ultrafiltration-diafiltration (UFDF). The triple helix collagen from UFDF process was used as substrate to produce collagen peptides by alcalase hydrolysis in an enzymatic membrane reactor (EMR) coupling with 1 kDa molecular weight cut off (MWCO) polysulfone hollow fiber membrane. The results showed that ASC extracted at high temperature (25 ˚C) with 0.5 M acetic acid for 5 h still preserved triple helix structure. In the UFDF process, the acid removal was higher than 90 % without any effect on ASC properties, particularly triple helix structure as indicated by circular dichroism spectrum. Moreover, Collagen from UFDF was used to produce collagen peptides by EMR. In EMR, collagen was pre-hydrolyzed by alcalase for 60 min before introduced to membrane separation. The EMR operation was operated for 10 h and provided a good of protein conversion stability. The results suggested that there is a successfulness of UF in application for acid removal to produce ASC with desirable preservation of its quality. In addition, the EMR was proven to be an effective process to produce low molecular weight peptides with ACE-inhibitory activity properties.

Keywords: acid soluble collagen, ultrafiltration-diafiltration, enzymatic membrane reactor, ace-inhibitory activity

Procedia PDF Downloads 463
7839 Investigation of the Aerodynamic Characteristics of a Vertical Take-Off and Landing Mini Unmanned Aerial Vehicle Configuration

Authors: Amir Abdelqodus, Mario Shehata

Abstract:

The purpose of the paper is to model and evaluate the aerodynamic coefficients and stability derivatives of a Vertical, Take-off and Landing Unmanned Aerial Vehicle configuration (VTOL UAV), which is a fixed wing UAV and a quad-copter hybrid capable of both vertical and conventional take-off and/or landing. The aerodynamic analysis of this configuration was carried out using CFD commercial package Ansys Fluent. Also, the aerodynamic coefficients for the case of the UAV without the quad-copter is carried out analytically using MATLAB programmed codes, and the resulting data is verified using Lifting Line Theory and potential method programs. The two results are then compared to understand the effect of adding the quad-copter on the aerodynamic performance of the UAV.

Keywords: aerodynamics, CFD, potential flow, UAV, VTOL

Procedia PDF Downloads 423
7838 Optical and Double Folding Analysis for 6Li+16O Elastic Scattering

Authors: Abd Elrahman Elgamala, N. Darwish, I. Bondouk, Sh. Hamada

Abstract:

Available experimental angular distributions for 6Li elastically scattered from 16O nucleus in the energy range 13.0–50.0 MeV are investigated and reanalyzed using optical model of the conventional phenomenological potential and also using double folding optical model of different interaction models: DDM3Y1, CDM3Y1, CDM3Y2, and CDM3Y3. All the involved models of interaction are of M3Y Paris except DDM3Y1 which is of M3Y Reid and the main difference between them lies in the different values for the parameters of the incorporated density distribution function F(ρ). We have extracted the renormalization factor NR for 6Li+16O nuclear system in the energy range 13.0–50.0 MeV using the aforementioned interaction models.

Keywords: elastic scattering, optical model, folding potential, density distribution

Procedia PDF Downloads 137
7837 Research Regarding Resistance Characteristics of Biscuits Assortment Using Cone Penetrometer

Authors: G.–A. Constantin, G. Voicu, E.–M. Stefan, P. Tudor, G. Paraschiv, M.–G. Munteanu

Abstract:

In the activity of handling and transport of food products, the products may be subjected to mechanical stresses that may lead to their deterioration by deformation, breaking, or crushing. This is the case for biscuits, regardless of their type (gluten-free or sugary), the addition of ingredients or flour from which they are made. However, gluten-free biscuits have a higher mechanical resistance to breakage or crushing compared to easily shattered sugar biscuits (especially those for children). The paper presents the results of the experimental evaluation of the texture for four varieties of commercial biscuits, using the penetrometer equipped with needle cone at five different additional weights on the cone-rod. The assortments of biscuits tested in the laboratory were Petit Beurre, Picnic, and Maia (all three manufactured by RoStar, Romania) and Sultani diet biscuits, manufactured by Eti Burcak Sultani (Turkey, in packs of 138 g). For the four varieties of biscuits and the five additional weights (50, 77, 100, 150 and 177 g), the experimental data obtained were subjected to regression analysis in the MS Office Excel program, using Velon's relationship (h = a∙ln(t) + b). The regression curves were analysed comparatively in order to identify possible differences and to highlight the variation of the penetration depth h, in relation to the time t. Based on the penetration depth between two-time intervals (every 5 seconds), the curves of variation of the penetration speed in relation to time were then drawn. It was found that Velon's law verifies the experimental data for all assortments of biscuits and for all five additional weights. The correlation coefficient R2 had in most of the analysed cases values over 0.850. The values recorded for the penetration depth were framed, in general, within 45-55 p.u. (penetrometric units) at an additional mass of 50 g, respectively between 155-168 p.u., at an additional mass of 177 g, at Petit Beurre biscuits. For Sultani diet biscuits, the values of the penetration depth were within the limits of 32-35 p.u., at an additional weight of 50 g and between 80-114 p.u., at an additional weight of 177g. The data presented in the paper can be used by both operators on the manufacturing technology flow, as well as by the traders of these food products, in order to establish the most efficient parametric of the working regimes (when packaging and handling).

Keywords: biscuits resistance/texture, penetration depth, penetration velocity, sharp pin penetrometer

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7836 All-Optical Function Based on Self-Similar Spectral Broadening for 2R Regeneration in High-Bit-Rate Optical Transmission Systems

Authors: Leila Graini

Abstract:

In this paper, we demonstrate basic all-optical functions for 2R regeneration (Re-amplification and Re-shaping) based on self-similar spectral broadening in low normal dispersion and highly nonlinear fiber (ND-HNLF) to regenerate the signal through optical filtering including the transfer function characteristics, and output extinction ratio. Our approach of all-optical 2R regeneration is based on those of Mamyshev. The numerical study reveals the self-similar spectral broadening very effective for 2R all-optical regeneration; the proposed design presents high stability compared to a conventional regenerator using SPM broadening with reduction of the intensity fluctuations and improvement of the extinction ratio.

Keywords: all-optical function, 2R optical regeneration, self-similar broadening, Mamyshev regenerator

Procedia PDF Downloads 176
7835 Control of Proton Exchange Membrane Fuel Cell Power System Using PI and Sliding Mode Controller

Authors: Mohamed Derbeli, Maissa Farhat, Oscar Barambones, Lassaad Sbita

Abstract:

Conventional controller (PI) applied to a DC/DC boost converter for the improvement and optimization of the Proton Exchange Membrane Fuel Cell (PEMFC) system efficiency, cannot attain a good performance effect. Thus, due to its advantages comparatively with the PI controller, this paper interest is focused on the use of the sliding mode controller (SMC), Stability of the closed loop system is analytically proved using Lyapunov approach for the proposed controller. The model and the controllers are implemented in the MATLAB and SIMULINK environment. A comparison of results indicates that the suggested approach has considerable advantages compared to the traditional controller.

Keywords: DC/DC boost converter, PEMFC, PI controller, sliding mode controller

Procedia PDF Downloads 223
7834 Effects of Asphalt Modification with Nanomaterials on Fresh and Stored Bitumen

Authors: Ahmed W. Oda, Ahmed El-Desouky, Hassan Mahdy, Osama M. Moussa

Abstract:

Nanomaterials have many applications in the field of asphalt paving. Two locally produced nanomaterials were used in the asphalt binder modification. The nanomaterials used are Nanosilica (NS), and Nanoclay (NC). The virgin asphalt binder was characterized by the conventional tests. The bitumen was modified by 3%, 5% and 7% of NS and NC. The penetration index(PI), and the retaining penetration (RP) was calculated based on the results of the penetration and the softening point tests. The results show that the RP becomes 95.35% at 5%NS modified bitumen and reaches 97.56% when bitumen is modified with 3% NC. The results show significant improvement in the bitumen stiffness when modified by the two types of nanomaterials, either fresh or aged (stored).

Keywords: bitumen, modified bitumen, aged, stored, nanomaterials

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7833 Hydrothermal Synthesis of ZIF-7 Crystals and Their Composite ZIF-7/CS Membranes for Water/Ethanol Separation

Authors: Kai-Sheng Ji, Yi-Feng Lin

Abstract:

The pervaporation process for solvent and water separation has attracted research attention due to its lower energy consumption compared with conventional distillation processes. The membranes used for the pervaporation approach should exhibit high flux and separation factors. In this study, the ZIF-7 crystal particles were successfully incorporated into chitosan (CS) membranes to form ZIF-7/CS mixed-matrix membranes. The as-prepared ZIF-7/CS mixed-matrix membranes were used to separate mixtures of water/ethanol at 25℃ in the pervaporation process. The mixed-matrix membranes with different ZIF-7 wt% incorporation showed better separation efficiency than the pristine CS membranes because of the smaller pore size of the mixed-matrix membranes. The separation factor and the flux of the ZIF-7/CS membranes clearly exceed the upper limit of the previously reported CS-based and mixed-matrix membranes.

Keywords: pervaporation, chitosan, ZIF-7, memberane separation

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7832 Metagenomics Analysis of Bacteria in Sorghum Using next Generation Sequencing

Authors: Kedibone Masenya, Memory Tekere, Jasper Rees

Abstract:

Sorghum is an important cereal crop in the world. In particular, it has attracted breeders due to capacity to serve as food, feed, fiber and bioenergy crop. Like any other plant, sorghum hosts a variety of microbes, which can either, have a neutral, negative and positive influence on the plant. In the current study, regions (V3/V4) of 16 S rRNA were targeted to extensively assess bacterial multitrophic interactions in the phyllosphere of sorghum. The results demonstrated that the presence of a pathogen has a significant effect on the endophytic bacterial community. Understanding these interactions is key to develop new strategies for plant protection.

Keywords: bacteria, multitrophic, sorghum, target sequencing

Procedia PDF Downloads 269
7831 Climate Change Effects on Agriculture

Authors: Abdellatif Chebboub

Abstract:

Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change’s representative concentration pathway with end-of-century radiative forcing of 8.5 W/m2. The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.

Keywords: climate change, agriculture, weather change, danger of climate change

Procedia PDF Downloads 301
7830 Genome-Wide Expression Profiling of Cicer arietinum Heavy Metal Toxicity

Authors: B. S. Yadav, A. Mani, S. Srivastava

Abstract:

Chickpea (Cicer arietinum L.) is an annual, self-pollinating, diploid (2n = 2x = 16) pulse crop that ranks second in world legume production after common bean (Phaseolus vulgaris). ICC 4958 flowers approximately 39 days after sowing under peninsular Indian conditions and the crop matures in less than 90 days in rained environments. The estimated collective yield losses due to abiotic stresses (6.4 million t) have been significantly higher than for biotic stresses (4.8 million t). Most legumes are known to be salt sensitive, and therefore, it is becoming increasingly important to produce cultivars tolerant to high-salinity in addition to other abiotic and biotic stresses for sustainable chickpea production. Our aim was to identify the genes that are involved in the defence mechanism against heavy metal toxicity in chickpea and establish the biological network of heavy metal toxicity in chickpea. ICC4958 variety of chick pea was taken and grown in normal condition and 150µM concentration of different heavy metal salt like CdCl₂, K₂Cr2O₇, NaAsO₂. At 15th day leave samples were collected and stored in RNA Later solution microarray was performed for checking out differential gene expression pattern. Our studies revealed that 111 common genes that involved in defense mechanism were up regulated and 41 genes were commonly down regulated during treatment of 150µM concentration of CdCl₂, K₂Cr₂O₇, and NaAsO₂. Biological network study shows that the genes which are differentially expressed are highly connected and having high betweenness and centrality.

Keywords: abiotic stress, biological network, chickpea, microarray

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7829 Magneto-Electric Behavior a Couple Aluminum / Steel Xc48

Authors: A. Mekroud, A. Khemis, M. S. Mecibah

Abstract:

The tribological behavior of a pin of paramagnetic material (aluminum), rolling on a rotating disk made of ferromagnetic material (steel XC48) in the presence of an externally applied alternating magnetic field, with the passage of electric current were studied. All tests were performed using a conventional tribometer pin- disk. Structural characterization of the surfaces in contact, oxides and wear debris, by X-ray diffraction (θ-2θ angle), showed the significant effect of magnetic field on the activation of the contact surface of the pin in no ferromagnetic material. The absence of the magnetic field causes a change of wear mode.

Keywords: structural characterization of the surfaces, oxides and wear debris, X-ray diffraction

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7828 Polar Nanoregions in Lead-Free Relaxor Ceramics: Unveiling through Impedance Spectroscopy

Authors: Mohammed Mesrar, Hamza El Malki, Hamza Mesrar

Abstract:

In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.

Keywords: (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3, Rietveld refinement, Scanning electron microscopy (SEM), Williamson-Hall plots, charge density distribution, dielectric properties

Procedia PDF Downloads 41
7827 Angle of Arrival Estimation Using Maximum Likelihood Method

Authors: Olomon Wu, Hung Lu, Nick Wilkins, Daniel Kerr, Zekeriya Aliyazicioglu, H. K. Hwang

Abstract:

Multiple Input Multiple Output (MIMO) radar has received increasing attention in recent years. MIMO radar has many advantages over conventional phased array radar such as target detection, resolution enhancement, and interference suppression. In this paper, the results are presented from a simulation study of MIMO Uniformly-Spaced Linear Array (ULA) antennas. The performance is investigated under varied parameters, including varied array size, Pseudo Random (PN) sequence length, number of snapshots, and Signal to Noise Ratio (SNR). The results of MIMO are compared to a traditional array antenna.

Keywords: MIMO radar, phased array antenna, target detection, radar signal processing

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7826 A Comparative Study of Standard, Casted, and Riveted Eye Design of a Mono Leaf Spring Using CAE Tools

Authors: Gian Bhushan, Vinkel Arora, M. L. Aggarwal

Abstract:

The objective of the present study is to determine better eye end design of a mono leaf spring used in light motor vehicle. A conventional 65Si7 spring steel leaf spring model with standard eye, casted and riveted eye end are considered. The CAD model of the leaf springs is prepared in CATIA and analyzed using ANSYS. The standard eye, casted, and riveted eye leaf springs are subjected to similar loading conditions. The CAE analysis of the leaf spring is performed for various parameters like deflection and Von-Mises stress. Mass reduction of 62.9% is achieved in case of riveted eye mono leaf spring as compared to standard eye mono leaf spring for the same loading conditions.

Keywords: CAE, leaf spring, standard, casted, riveted eye

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7825 Study on Electromagnetic Plasma Acceleration Using Rotating Magnetic Field Scheme

Authors: Takeru Furuawa, Kohei Takizawa, Daisuke Kuwahara, Shunjiro Shinohara

Abstract:

In the field of a space propulsion, an electric propulsion system has been developed because its fuel efficiency is much higher than a conventional chemical one. However, the practical electric propulsion systems, e.g., an ion engine, have a problem of short lifetime due to a damage of generation and acceleration electrodes of the plasma. A helicon plasma thruster is proposed as a long-lifetime electric thruster which has non-direct contact electrodes. In this system, both generation and acceleration methods of a dense plasma are executed by antennas from the outside of a discharge tube. Development of the helicon plasma thruster has been conducting under the Helicon Electrodeless Advanced Thruster (HEAT) project. Our helicon plasma thruster has two important processes. First, we generate a dense source plasma using a helicon wave with an excitation frequency between an ion and an electron cyclotron frequencies, fci and fce, respectively, applied from the outside of a discharge using a radio frequency (RF) antenna. The helicon plasma source can provide a high-density (~1019 m-3), a high-ionization ratio (up to several tens of percent), and a high particle generation efficiency. Second, in order to achieve high thrust and specific impulse, we accelerate the dense plasma by the axial Lorentz force fz using the product of the induced azimuthal current jθ and the static radial magnetic field Br, shown as fz = jθ × Br. The HEAT project has proposed several kinds of electrodeless acceleration schemes, and in our particular case, a Rotating Magnetic Field (RMF) method has been extensively studied. The RMF scheme was originally developed as a concept to maintain the Field Reversed Configuration (FRC) in a magnetically confined fusion research. Here, RMF coils are expected to generate jθ due to a nonlinear effect shown below. First, the rotating magnetic field Bω is generated by two pairs of RMF coils with AC currents, which have a phase difference of 90 degrees between the pairs. Due to the Faraday’s law, an axial electric field is induced. Second, an axial current is generated by the effects of an electron-ion and an electron-neutral collisions through the Ohm’s law. Third, the azimuthal electric field is generated by the nonlinear term, and the retarding torque generated by the collision effects again. Then, azimuthal current jθ is generated as jθ = - nₑ er ∙ 2π fRMF. Finally, the axial Lorentz force fz for plasma acceleration is generated. Here, jθ is proportional to nₑ and frequency of RMF coil current fRMF, when Bω is fully penetrated into the plasma. Our previous study has achieved 19 % increase of ion velocity using the 5 MHz and 50 A of the RMF coil power supply. In this presentation, we will show the improvement of the ion velocity using the lower frequency and higher current supplied by RMF power supply. In conclusion, helicon high-density plasma production and electromagnetic acceleration by the RMF scheme with a concept of electrodeless condition have been successfully executed.

Keywords: electric propulsion, electrodeless thruster, helicon plasma, rotating magnetic field

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7824 Initializing E-Classroom in a Multigrade School in the Philippines

Authors: Karl Erickson I. Ebora

Abstract:

Science and technology are two inseparable terms which bring wonders to all aspects of life such as education, medicine, food production and even the environment. In education, technology has become an integral part as it brings many benefits to the teaching-learning process. However, in the Philippines, being one of the developing countries resources are scarce and not all schools enjoy the fruits brought by technology. Much of this ordeal impacts that of multigrade instruction. These schools are often the last priority in resources allocation since these have limited number of students. In fact, it is not surprising that these schools do not have even a single computer unit much more a computer laboratory. This paper sought to present a plan on how public schools would receive its e-classroom. Specifically, this paper sought to answer questions like the level of the school readiness in terms of facilities and equipment; the attitude of the respondents towards the use of e-classroom; level of teacher’s familiarity in using different e-classroom software and the plans of interventions undertaken by the school to make it e-classroom ready. After gathering and analysing the necessary data, this paper came up with the following conclusions that in terms of facilities and equipment, Guisguis Talon Elementary School (Main), though a multigrade school, is ready to receive e-classroom.; that the respondents show positive disposition in technology utilization in teaching after they strongly agree that technology plays essential role in the teaching-learning process. Also, they strongly agree that technology is a good motivator; it makes the teaching and learning more interesting and effective; it makes teaching easy; and that technology enhances student’s learning. Additionally, Teacher-respondents in Guisguis Talon Elementary School (Main) show familiarity in using software. They are very familiar with MS Word; MS Excel; MS PowerPoint; and internet and email. Moreover, they are very familiar with basic e-classroom computer operations and basic application software. They are very familiar with MS office and can do simple editing and formatting; in accessing and saving information from CD/DVD, external hard drives, USB and the like; and in browsing effectively different search engines and educational sites, download and upload files. Likewise respondents strongly agree to the interventions undertaken by the school to make it e-classroom ready. They strongly agree that funding and support are needed by the school; that stakeholders should be encouraged to consider donating of equipment; and that school and community should try to mobilize their resources in order to help the school; that the teachers should be provided with trainings in order for them to be technologically competent; and that principals and administrators should motivate their teachers to undergo continuous professional development.

Keywords: e-classroom, multi-grade school, DCP, classroom computers

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7823 Undrained Bearing Capacity of Circular Foundations on two Layered Clays

Authors: S. Benmebarek, S. Benmoussa, N. Benmebarek

Abstract:

Natural soils are often deposited in layers. The estimation of the bearing capacity of the soil using conventional bearing capacity theory based on the properties of the upper layer introduces significant inaccuracies if the thickness of the top layer is comparable to the width of the foundation placed on the soil surface. In this paper, numerical computations using the FLAC code are reported to evaluate the two clay layers effect on the bearing capacity beneath rigid circular rough footing subject to axial static load. The computation results of the parametric study are used to illustrate the sensibility of the bearing capacity, the shape factor and the failure mechanisms to the layered strength and layered thickness.

Keywords: numerical modeling, circular footings, layered clays, bearing capacity, failure

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7822 Ballistic Transport in One-Dimensional Random Dimer Photonic Crystals

Authors: Samira Cherid, Samir Bentata, F. Zahira Meghoufel, Sabria Terkhi, Yamina Sefir, Fatima Bendahma, Bouabdellah Bouadjemi, Ali Z. Itouni

Abstract:

In this work, we examined the propagation of light in one-dimensional systems is examined by means of the random dimer model. The introduction of defect elements, randomly in the studied system, breaks down the Anderson localization and provides a set of propagating delocalized modes at the corresponding conventional dimer resonances. However, tuning suitably the defect dimer resonance on the host ones (or vice versa), the transmission magnitudes can be enhanced providing the optimized ballistic transmission regime as an average response. Hence, ballistic optical filters can be conceived at desired wavelengths.

Keywords: photonic crystals, random dimer model, ballistic resonance, localization and transmission

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7821 Flip-Chip Bonding for Monolithic of Matrix-Addressable GaN-Based Micro-Light-Emitting Diodes Array

Authors: Chien-Ju Chen, Chia-Jui Yu, Jyun-Hao Liao, Chia-Ching Wu, Meng-Chyi Wu

Abstract:

A 64 × 64 GaN-based micro-light-emitting diode array (μLEDA) with 20 μm in pixel size and 40 μm in pitch by flip-chip bonding (FCB) is demonstrated in this study. Besides, an underfilling (UF) technology is applied to the process for improving the uniformity of device. With those configurations, good characteristics are presented, operation voltage and series resistance of a pixel in the 450 nm flip chip μLEDA are 2.89 V and 1077Ω (4.3 mΩ-cm²) at 25 A/cm², respectively. The μLEDA can sustain higher current density compared to conventional LED, and the power of the device is 9.5 μW at 100 μA and 0.42 mW at 20 mA.

Keywords: GaN, micro-light-emitting diode array(μLEDA), flip-chip bonding, underfilling

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7820 Chronic Aflatoxin Exposure During Pregnancy Is Associated With Lower Fetal Growth Trajectories: A Prospective Cohort Study in Rural Ethiopia

Authors: K. Tesfamariam, S. Gebreyesus, C. Lachat, P. Kolsteren, S. De Saeger, M. De Boevre, A. Argaw

Abstract:

Aflatoxins are toxic secondary metabolites produced by Aspergillus fungi, which are ubiquitously present in the food supplies of low- and middle-income countries. Studies of maternal aflatoxin exposure and fetal outcomes are mainly focused on size at birth and the effect on intrauterine fetal growth has not been assessed using repeated longitudinal fetal biometry across gestation. Therefore, this study intends to assess the association between chronic aflatoxin exposure during pregnancy and fetal growth trajectories in a rural Ethiopian setting. In a prospective cohort study, we enrolled 492 pregnant women. A phlebotomist collected 5 mL of a venous blood sample from eligible women before 28 completed weeks of gestation and aflatoxin B1-lysine concentration was determined using liquid chromatography-tandem mass spectrometry. The mean (±SD) gestational age was 19.1 (3.71) weeks at enrollment, and 28.5 (3.51) and 34.5 (2.44) weeks of gestation at the second and third rounds of ultrasound measurements, respectively. Estimated fetal weight was expressed in centiles using the INTERGROWTH-21st reference. We fitted a multivariable linear mixed-effects model to estimate the rate of fetal growth between aflatoxin-exposed (i.e., aflatoxin B1-lysine concentration above or equal to the limit of detection) and non-exposed mothers in the study. Mothers had a mean (±SD) age of 26.0 (4.58) years. The median (P25, P75) serum AFB1-lysine concentration was 12.6 (0.93, 96.9) pg/mg albumin, and aflatoxin exposure was observed in 86.6% of maternal blood samples. Eighty-five percent of the women enrolled provided at least two ultrasound measurements for analysis. On average, the aflatoxin-exposed group had a significantly lower change over time in fetal weight-for-gestational age centile than the unexposed group (ß = -1.01 centiles/week, 95% CI: -1.87, -0.15, p = 0.02). Chronic maternal AF exposure is associated with lower fetal weight gain over time. Our findings emphasize the importance of nutrition-sensitive strategies to mitigate dietary aflatoxin exposure as well as adopting food safety measures in low-income settings, particularly during the fetal period of development.

Keywords: aflatoxin, fetal growth, low-income setting, mycotoxins

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7819 Direct Torque Control of Induction Motor Employing Teaching Learning Based Optimization

Authors: Anam Gopi

Abstract:

The undesired torque and flux ripple may occur in conventional direct torque control (DTC) induction motor drive. DTC can improve the system performance at low speeds by continuously tuning the regulator by adjusting the Kp, Ki values. In this Teaching Learning Based Optimization (TLBO) is proposed to adjust the parameters (Kp, Ki) of the speed controller in order to minimize torque ripple, flux ripple, and stator current distortion. The TLBO based PI controller has resulted is maintaining a constant speed of the motor irrespective of the load torque fluctuations.

Keywords: teaching learning based optimization, direct torque control, PI controller

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7818 Effects of the Supplementation of Potassium Humate at Different Levels to the Dairy Cows' Concentrated Mix during Dry Period on Early Lactation Yield Parameters and Dam/Calf Immunity

Authors: Cangir Uyarlar, E. Eren Gultepe, I. Sadi Cetingul, Ismail Bayram

Abstract:

This study was conducted to investigate the effect of humic acid (Potassium Humate) at different levels on rations on the effects of both maternal and offspring health, metabolic parameters and immunity levels in transition dairy cows. For this purpose, 50 Holstein dairy cows divided 5 trial groups. Experimental groups were designed as follows: A) Control (0% Humas); B) 0.5 Humas (0,5% in concentrated diet); C) 1 Humas (1% in concentrated diet), D) 1,5 Humas (1,5% in concentrated diet), E) 2 Humas (2% in concentrated diet), respectively. The study lasted from the first day of the dry period to postpartum 30th day. Diets were prepared as isocaloric and isonitrogenic. In the experiment, the day on which the animals gave birth was accepted as ‘0 (zero)’ and blood was taken from tail vein (v. coccygea) at -60, -53, -46, -39, -32, -25, -18, -11, -4, 0, ; Colostrum samples were taken on days 0, 1 and 2; Blood samples were taken on days 0, 1, 2, 15 and 30 from the juguler vein (v. jugularis) of the new born calves. Total blood leukocyte, Lymphocyte, Monocyte, granulocytes, Hemoglobin, Hematocrit, MCV, MCH, MWC, RDW, PLT, MPV, PDW, PCT, NEFA, BHBA, Glucose, Total Cholesterol , Triglyceride, LDL, HDL, VLDL, ALT, AST, ALP, GGT and Total IgG levels and colostrum IgG levels were determined in this experiment. The results suggest that although the supplementation of humic acid at 2% level adversely affected to production parameters, the addition of humic acid (potassium humate) to the concentrate mix during the dry period (particularly 0.5 and 1% levels) may provide an increasing on mother and the offspring immunity, some improving on serum metabolism parameters and enhancing the milk production.

Keywords: humic acid, dairy cow, calf, immunity

Procedia PDF Downloads 193
7817 Redesigning Malaysia Batik Sarong by Applying Quality Function Deployment

Authors: M. Kamal, Y. Wang, R. Kennon

Abstract:

Quality Function Deployment is a useful tool in product development with the application of voice of customer. In this paper, it aims to be applied as a product development tool in redesigning fashion and textile product. The purpose of these studies is to apply the effective use of Voice of Customer in redesigning cultural fashion product. The data collection from Voice of Customer or consumers’ feedback might help the producer to improve the quality of merchandise ahead. Voice of Customer could give a specific detailing for quality which needs to be redesigned according to customers’ requirements. Meanwhile, the next objective is to differentiate design specifications and characteristics using House of Quality. In product designing phase, it is very important to distinguish each specification and characteristic which translated from Voice of Customer to House of Quality matrix. This matrix would help designers to development according to qualities that customer wants for the better and successful product in the market. It is hope this research would indicate the customers’ requirements and production team idea might be measured and translated to a systematic data. The specific technical data could be planned ahead with specific design details as well. This could be a sustainable approach for a traditional product which could control the material that they use and sustain the quality as the past production. As a conclusion, this study would benefit the Small Medium Enterprises design team or the designers to style an item from customers view with organised projection of the product. The finding also could assist designers or batik producers’ to recognise specific details Batik sarong from consumers as well as in in advertising and marketing strategy plan.

Keywords: house of quality, Malaysia batik sarong, quality function deployment, voice of customer

Procedia PDF Downloads 582
7816 The Influence of Reaction Parameters on Magnetic Properties of Synthesized Strontium Ferrite

Authors: M. Bahgat, F. M. Awan, H. A. Hanafy

Abstract:

The conventional ceramic route was utilized to prepare a hard magnetic powder (M-type strontium ferrite, SrFe12O19). The stoichiometric mixture of iron oxide and strontium carbonate were calcined at 1000°C and then fired at various temperatures. The influence of various reaction parameters such as mixing ratio, calcination temperature, firing temperature and firing time on the magnetic behaviors of the synthesized magnetic powder were investigated.The magnetic properties including Coercivity (Hc), Magnetic saturation (Ms), and Magnetic remnance (Mr) were measured by vibrating sample magnetometer. Morphologically the produced magnetic powder has a dense hexagonal grain shape structure.

Keywords: hard magnetic materials, ceramic route, strontium ferrite, magnetic properties

Procedia PDF Downloads 678