Search results for: current density distribution
8693 Investigating the Role of Lactiplantibacillus Plantarum vs. Spontaneous Fermentation in Improving Nutritional and Consumer Safety of the Fermented White Cabbage Sprouts
Authors: Anam Layla, Qamar Abbas Syed, Tahir Zahoor, Muhammad Shahid
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Brassicaceae sprouts are promising candidates for functional food because of their unique phytochemistry and high nutrient density compared to their seeds and matured vegetables. Despite being admired for their health-promoting properties, white cabbage sprouts have been least explored for their nutritional significance and behavior to lactic acid fermentation. This study aimed to investigate the role of lactic acid fermentation i.e., inoculum vs. spontaneous, in reducing intrinsic toxicants load and improving nutrients delivering potential of the white cabbage sprouts. White cabbage sprouts with a 5 – 7 cm average size were processed as raw, blanched, Lactiplantibacillus plantarum inoculated fermentation and spontaneous fermentation. Plant material was dehydrated at 40˚C and evaluated for microbiological quality, macronutrients, minerals, and anti-nutrient contents. The results indicate L. plantarum inoculum fermentation of blanched cabbage sprouts (IF-BCS) to increase lactic acid bacteria count of the sprouts from 0.97 to 8.47 log CFU/g. Compared with the raw cabbage sprouts (RCS), inoculum fermented-raw cabbage sprouts (IF-RCS), and spontaneous fermented-raw cabbage sprouts (SF-RCS), the highest content of Ca (447 mg/ 100g d.w.), Mg (204 mg/100g d.w.), Fe (9.3 mg/100g d.w.), Zn (5 mg/100g d.w.) and Cu (0.5 mg/100g d.w.) were recorded in IF-BCS. L. plantarum led fermentation of BCS demonstrated a reduction in phytates, tannins, and oxalates contents at a rate of 42%, 66%, and 53%, respectively, while standalone lactic acid fermentation of the raw sprouts reduced the burden of anti-nutrients in a range between 32 to 56%. The results suggest L. plantarum led lactic acid fermentation coupled with sprouts blanching is the most promising way to improve the nutritional quality and safety of the white cabbage sprouts.Keywords: lactic acid fermentation, anti-nutrients, mineral content, nutritional quality
Procedia PDF Downloads 628692 Performance Analysis of PAPR Reduction in OFDM Systems based on Partial Transmit Sequence (PTS) Technique
Authors: Alcardo Alex Barakabitze, Tan Xiaoheng
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Orthogonal Frequency Division Multiplexing (OFDM) is a special case of Multi-Carrier Modulation (MCM) technique which transmits a stream of data over a number of lower data rate subcarriers. OFDM splits the total transmission bandwidth into a number of orthogonal and non-overlapping subcarriers and transmit the collection of bits called symbols in parallel using these subcarriers. This paper explores the Peak to Average Power Reduction (PAPR) using the Partial Transmit Sequence technique. We provide the distribution analysis and the basics of OFDM signals and then show how the PAPR increases as the number of subcarriers increases. We provide the performance analysis of CCDF and PAPR expressed in decibels through MATLAB simulations. The simulation results show that, in PTS technique, the performance of PAPR reduction in OFDM systems improves significantly as the number of sub-blocks increases. However, by keeping the same number of sub-blocks variation, oversampling factor and the number of OFDM blocks’ iteration for generating the CCDF, the OFDM systems with 128 subcarriers have an improved performance in PAPR reduction compared to OFDM systems with 256, 512 or >512 subcarriers.Keywords: OFDM, peak to average power reduction (PAPR), bit error rate (BER), subcarriers, wireless communications
Procedia PDF Downloads 5178691 A Bibliometric Analysis of the Structural Equation Modeling in Education
Authors: Lim Yi Wei
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Structural equation modelling (SEM) is well-known in statistics due to its flexibility and accessibility. It plays an increasingly important role in the development of the education field. The number of research publications using SEM in education has increased in recent decades. However, there is a lack of scientific review conducted on SEM in education. The purpose of this study is to investigate research trends related to SEM in education. The researcher will use Vosviewer, Datawrapper, and SciMAT to do bibliometric analysis on 5549 papers that have been published in the Scopus database in the last five years. The result will show the publication trends of the most cited documents, the top contributing authors, countries, institutions, and journals in the research field. It will also look at how they relate to each other in terms of co-citation, collaboration, and co-occurrence of keywords. This study will benefit researchers and practitioners by identifying research trends and the current state of SEM in education.Keywords: structural equation modeling, education, bibliometric analysis, Vosviewer
Procedia PDF Downloads 1058690 Chemical and Mineralogical Properties of Soils from an Arid Region of Misurata-Libya: Treated Wastewater Irrigation Impacts
Authors: Khalifa Alatresh, Mirac Aydin
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This research explores the impacts of irrigation by treated wastewater (TWW) on the mineralogical and chemical attributes of sandy calcareous soils in the Southern region of Misurata. Soil samples obtained from three horizons (A, B, and C) of six TWW-irrigated pedons (29years) and six other pedons from nearby non-irrigated areas (dry-control). The results demonstrated that the TWW-irrigated pedons had significantly higher salinity (EC), sodium adsorption ratio (SAR), exchangeable sodium percentage (ESP), cation exchange capacity (CEC), available phosphor (AP), total nitrogen (TN), and organic matter (OM) relative to the control pedons. Nonetheless, all the values of interest (EC < 4000 µs/cm < SAR < 13, pH < 8.5 and ESP < 15) remained lower than the thresholds, showing no issues with sodicity or salinity. Irrigated pedons contained significantly higher amounts of total clay and showed an altered distribution of particle sizes and minerals identified (quartz, calcite, microcline, albite, anorthite, and dolomite) within the profile. The observed results included the occurrence of Margarite, Anorthite, Chabazite, and Tridymite minerals after the application of TWW in small quantities that are not enough to influence soil genesis and classification.0,51 cm.Keywords: treated wastewater, sandy calcareous soils, soil mineralogy, and chemistry
Procedia PDF Downloads 1198689 Geochemical Approach of Rare Earth Element Distribution: A Case Study from Lake Acigol, Denizli, Turkey
Authors: M. Budakoglu, M. Karaman, A. Abdelnasser, D. Kiran, M. Kumral
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About 50 mg lake sediment was digested in two steps. While first stage was completed with 6 ml 37% HCl, 2 ml 65% HNO3 and 1 ml 38-40% HF in an pressure and temperature controlled Teflon beaker using Berghoff Microwave™ at average 135°C, digestion procedure was completed with the addition of 6 ml 5% boric acid solution. REE contents of sediment samples were determined by Perkin Elmer DRC II ICP-MS in Geochemistry Research Laboratories (JAL/GRL) of Faculty of Mines, Istanbul Technical University. Chondrite-normalized REE patterns of Lake Acıgöl sediments show generally high abundance of REE compared to chondritic concentrations, with particular enrichment in LREE [(La/Lu)N = 4.85-19.90], [(La/Lu)N = 7.09-15.14], [(La/Lu)N = 9.42-15.52] and [(La/Lu)N = 7.69-15.63] for the surface sediment and 0-10 cm-, 10-20 cm- and 20-30 cm-subsurface sediments respectively. Also these samples showed flat HREE normalized to chondrite as (La/Sm)N ranging from 2.98 to 4.8 for surface sediments and for subsurface sediments from 3.28 to 3.97 (0-10 cm), 3.57 to 3.94 (10-20 cm) and 3.36 to 3.94 (20-30 cm) while (Gd/Yb)N ranging from 2.14 to 2.93, from 2.03 to 2.76, from 2.26 to 2.79 and from 2.05 to 2.76 from the surface and subsurface sediments respectively. Moreover, their REE profiles are similar to profiles of the continental collision basin (CCB) with negative Eu anomalies. In addition, their REE patterns illustrate generally low abundance of REE compared to concentrations of NASC, PAAS and UCC with very slight enrichment of LREE and positive Eu* anomalies. Therefore there is no comparable between our samples of surface and subsurface sediments and these types of international sediments.Keywords: chondrite-normalized REE patterns, hypersaline lake, surface sediments, subsurface sediments, Lake Acıgöl, Turkey
Procedia PDF Downloads 5248688 Sorption of Cesium Ions from Aqueous Solutions by Magnetic Multi-Walled Carbon Nanotubes Functionalized with Zinc Hexacyanoferrate
Authors: H. H. Lee, D. Y. Kim, S. W. Lee, J. H. Kim, J. H. Kim, W. Z. Oh, S. J. Choi
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In recent years, carbon nanotubes (CNTs) have been widely employed as a sorbent for the removal of various metal ions from water due to their unique properties such as large surface area, light mass density, high porous and hollow structure, and strong interaction between the pollutant molecules and CNTs. To apply CNTs to the sorption of Cs+ from aqueous solutions, they must first be functionalized to increase their hydrophilicity and therefore, enhance their applicability to the sorption of polar and relatively low-molecular-weight species. The objective of this study is to investigate the preparation of magnetically separable multi-walled carbon nanotubes (MWCNTs-m) as a sorbents for the removal of Cs+ from aqueous solutions. The MWCNTs-m was prepared using pristine MWCNTs and iron precursor Fe(acac)3. For the selective removal of Cs+ from aqueous solutions, the MWCNTs-m was functionalized with zinc hexacyanoferrate (MWCNTs-m-ZnFC). The physicochemical properties of the synthesized sorbents were characterized with various techniques, including transmission electron microscopy (TEM), specific surface area analysis, Fourier transform-infrared (FT-IR) spectroscopy, and vibrating-sample magnetometer. The MWCNTs-m-ZnFC was found to be easily separated from aqueous solutions by using magnetic field. The MWCNTs-m-ZnFC exhibited a high capacity for sorbing Cs+ from aqueous solutions because of their strong affinity for Cs+ and specific surface area. The sorption ability of the MWCNTs-m-ZnFC for Cs+ was maintained even in the presence of co-existing ions (Na+). Considering these results, the CNT-m-ZnFCs have great potential for use as an effective sorbent for the selective removal of radioactive Cs+ ions from aqueous solutions.Keywords: multi-walled carbon nanotubes, magnetic materials, cesium, zinc hexacyanoferrate, sorption
Procedia PDF Downloads 3278687 Effect of Geomagnetic Field on Motion of Conductor
Authors: Bharti Gupta, Alaukik Sharma
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The first aim is to determine the effect of the Earth's magnetic field on the motion of a conductor to evaluate the variations of the orbital elements of the conductor due to these effects. The effects of Earth's magnetic field on the motion of conductors have been studied at different heights, longitudes and latitudes. When the conductor cut the geomagnetic line of force, then an electro-motive force (EMF) is induced across to the conductor. Due to this induced EMF, an induced current will flow through the conductor. Resulting, a Lorentz force will be applied on the conductor who opposes the motion of the conductor. So our second aim is to determine the accurate value of Induced EMF and induced Lorentz Force at different heights, longitudes and latitudes.Keywords: induced EMF, Lorentz force, geomagnetic lines of force, moving conductor
Procedia PDF Downloads 1608686 Determination of Parasitic Load in Different Tissues of Murine Toxoplasmosis after Immunization by Excretory-Secretory Antigens using Real Time QPCR
Authors: Ahmad Daryani, Yousef Dadimoghaddam, Mehdi Sharif, Ehsan Ahmadpour, Shahabeddin Sarvi, Baghar Hashemi
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Background: Excretory-secretory antigens (ESAs) of Toxoplasma gondii are one of the candidates for immunization against toxoplasmosis. For evaluation of immunization, we determined the kinetics of the distribution of Toxoplasma and parasite load in different tissues of mice immunized by ESAs. Methods: In this experimental study, 36 mice in case (n= 18) and control (n= 18) groups were immunized with ESAs and PBS, respectively. After 2 weeks, mice were challenged intraperitoneally with Toxoplasma virulent RH strain. Blood and different tissues (brain, spleen, liver, heart, kidney, and muscle) were collected daily after challenge (1, 2, 3 and last day before death). Parasite load was calculated using Real time QPCR targeted at the B1 gene. Results: ESAs as vaccine in different tissues showed various effects. However, infected mice which received the vaccine in comparison with control group, displayed a drastically decreasing in parasite burden, in their blood and tissues (P= 0.000). Conclusion: These results indicated that ESAs with reduction of parasite load in different tissues of host could be evaluable candidate for the development of immunization strategies against toxoplasmosis.Keywords: parasitic load, murine toxoplasmosis, immunization, excretory-secretory antigens, real time QPCR
Procedia PDF Downloads 4478685 Population Dynamics of Juvenile Dusky Groupers, Epinephelus Marginatus: "Lowe, 1834" From Two Sites in Terceira Island, Azores, Portugal
Authors: Regina Streltsov
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The Archipelago of the Azores in the NE Atlantic is a hot spot of marine biodiversity, both pelagic and demersal. Epinephelus marginatus is a solitary species commonly observed in these waters, with distinct territorial/residential behaviors from their post- larva and juvenile stages to the adult phase. Being commercially high valued species, about 13% of all groupers (Family Epinephelidae) face an increasing pressure that has produced known impacts in both the abundance and distribution of this group of fishes. Epinephelus marginatus is currently assessed by the IUCN as a vulnerable species. Dusky gropers inhabit rocky bottoms from shallow waters down to 200 m. Juveniles are usually found in shallow shoreline waters. Population dynamics of juveniles can lead to a better understanding of the competition for resources and predation and further conservation measures that must be taken upon dusky groupers. This study is carried out in rocky reefs from two sheltered bays on the south and north coast of the island in two different spots with four sampling sites in total. Using Transects individuals are counted at the peak of high tide and all abiotic factors are recorded. Our goal is to complete a statistically significant number of observations in order to detail these populations and to better understand their dynamics and dimension.Keywords: Azores, dusky groupers, Epinephelus marginatus, population dynamics
Procedia PDF Downloads 1608684 Influence of Produced Water Mixed With Crude Oil on the Geotechnical Properties of Sandy Soil
Authors: Khalifa Abdunaser
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This study investigated the effects of oil contamination due to pro-duced water leaks that created lakes decades ago, as well as the extent of its im-pact on altering the geotechnical characteristics of the soil, which could act as a barrier to groundwater access The concentration of total petroleum hydrocarbons (TPH), which is the main component in the contaminated soil, was measured using a variety of analyses. Additionally, some extensive laboratory tests were performed to examine the effects on the soil's geotechnical properties, including particle size distribution, shear strength, consistency limits, specific gravity, and permeability coefficient. A clear decrease in TPH concentration was observed with increasing depth, and it is expected to end within only a few meters. It was found that there is a signifi-cant effect of this pollutant on the size of the soil particles, which led to them be-coming coarser than the uncontaminated soil particles. Moreover, it causes a de-crease in fluid and plastic boundaries, as well as an increase in cohesion between soil particles. However, the angle of internal friction decreases with the increase in the content of petroleum hydrocarbons in the soil samples. It came to light that determining the permeability coefficient as one of the physical characteristics of the most important factors responsible for the passage of pollutants in the groundwater, as it showed an obvious reduction in the permeability, which is the main reason dealt as an obstacle to the arrival of oil pollutants to the groundwater.Keywords: TPH, specific gravity, oil lake, Libya
Procedia PDF Downloads 998683 Numerical Investigation of the Evaporation and Mixing of UWS in a Diesel Exhaust Pipe
Authors: Tae Hyun Ahn, Gyo Woo Lee, Man Young Kim
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Because of high thermal efficiency and low CO2 emission, diesel engines are being used widely in many industrial fields although it makes many PM and NOx which give both human health and environment a negative effect. NOx regulations for diesel engines, however, are being strengthened and it is impossible to meet the emission standard without NOx reduction devices such as SCR (Selective Catalytic Reduction), LNC (Lean NOx Catalyst), and LNT (Lean NOx Trap). Among the NOx reduction devices, urea-SCR system is known as the most stable and efficient method to solve the problem of NOx emission. But this device has some issues associated with the ammonia slip phenomenon which is occurred by shortage of evaporation and thermolysis time, and that makes it difficult to achieve uniform distribution of the injected urea in front of monolith. Therefore, this study has focused on the mixing enhancement between urea and exhaust gases to enhance the efficiency of the SCR catalyst equipped in catalytic muffler by changing inlet gas temperature and spray conditions to improve the spray uniformity of the urea water solution. Finally, it can be found that various parameters such as inlet gas temperature and injector and injection angles significantly affect the evaporation and mixing of the urea water solution with exhaust gases, and therefore, optimization of these parameters are required.Keywords: UWS (Urea-Water-Solution), selective catalytic reduction (SCR), evaporation, thermolysis, injection
Procedia PDF Downloads 4008682 Developing Artistic Concepts for Kindergarten Children in Egypt Using Graphic Activities
Authors: Mona Yacoub, Ahmed Amin Mousa
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The current work presents a program for children in Egypt. This program involved a collection of artistic activities that purposes to improve some language, artistic skills of kindergarten children. The researchers have prepared a questionnaire for the link between the target group and the content. The questionnaire has been presented to experts for adjudicating. The program was applied to a group of 30 children. Another questionnaire has been prepared by the researchers for measuring the activities’ effect on the children. The second questionnaire was considered as the pre-test and post-test. Finally, after applying the activities and the questionnaire, the researchers detected a significant difference in favor of the post-test results.Keywords: Developing, concepts, kindergarten, children, graphic activities
Procedia PDF Downloads 1668681 Morphology of the Acetabular Cartilage Surface in Elderly Cadavers Analyzing the Contact between the Acetabulum and Femoral Head
Authors: Keisuke Akiyama, Takashi Sakai, Junichiro Koyanagi, Hideki Yoshikawa, Kazuomi Sugamoto
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The geometry of acetabular cartilage surface plays an important role in hip joint biomechanics. The aim of this study was to analyze the morphology of acetabular articular cartilage surface in elderly subjects using a 3D-digitizer. Twenty hemipelves from 12 subjects (mean ages 85 years) were scanned with 3D-digitizer. Each acetabular surface model was divided into four regions: anterosuperior (AS), anteroinferior (AI), posterosuperior (PS), and posteroinferior (PI). In the global acetabulum and each region, the acetabular sphere radius and the standard deviation (SD) of the distance from the acetabular sphere center to the acetabular cartilage surface were calculated. In the global acetabulum, the distance between the acetabular surface model and the maximum sphere which did not penetrate over the acetabular surface model was calculated as the inferred femoral head, and then the distribution was mapped at intervals of 0.5 mm. The SD in AS was significantly larger than that in AI (p = 0.006) and PI (p = 0.001). The SD in PS was significantly larger than that in PI (p = 0.005). The closest region (0-0.5 mm) tended to be distributed at anterior or posterosuperior acetabular edge. The contact between the femoral head and acetabulum might start at the periphery of the lunate surface, especially in the anterior or posterosuperior region. From viewpoint of acetabular morphology, the acetabular articular cartilage in the anterior or posterosuperior edge could be more vulnerable due to direct contact mechanism.Keywords: acetabulum, cartilage, morphology, 3D-digitizer
Procedia PDF Downloads 3488680 Research on High Dielectric HfO₂ Stack Structure Applied to Field Effect Transistors
Authors: Kuan Yu Lin, Shih Chih Chen
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This study focuses on the Al/HfO₂/Si/Al structure to explore the electrical properties of the structure. This experiment uses a radio frequency magnetron sputtering system to deposit high dielectric materials on p-type silicon substrates of 1~10 Ω-cm (100). Consider the hafnium dioxide film as a dielectric layer. Post-deposition annealing at 750°C in nitrogen atmosphere. Electron beam evaporation of metallic aluminum is then used to complete the top/bottom electrodes. The metal is post-annealed at 450°C for 20 minutes in a nitrogen environment to complete the MOS component. Its dielectric constant, equivalent oxide layer thickness, oxide layer defects, and leakage current mechanism are discussed. At PDA 750°C-5s, the maximum k value was found to be 21.2, and the EOT was 3.68nm.Keywords: high-k gate dielectrics, HfO₂, post deposition annealing, RF magnetic
Procedia PDF Downloads 618679 Solar Power Generation in a Mining Town: A Case Study for Australia
Authors: Ryan Chalk, G. M. Shafiullah
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Climate change is a pertinent issue facing governments and societies around the world. The industrial revolution has resulted in a steady increase in the average global temperature. The mining and energy production industries have been significant contributors to this change prompting government to intervene by promoting low emission technology within these sectors. This paper initially reviews the energy problem in Australia and the mining sector with a focus on the energy requirements and production methods utilised in Western Australia (WA). Renewable energy in the form of utility-scale solar photovoltaics (PV) provides a solution to these problems by providing emission-free energy which can be used to supplement the existing natural gas turbines in operation at the proposed site. This research presents a custom renewable solution for the mining site considering the specific township network, local weather conditions, and seasonal load profiles. A summary of the required PV output is presented to supply slightly over 50% of the towns power requirements during the peak (summer) period, resulting in close to full coverage in the trench (winter) period. Dig Silent Power Factory Software has been used to simulate the characteristics of the existing infrastructure and produces results of integrating PV. Large scale PV penetration in the network introduce technical challenges, that includes; voltage deviation, increased harmonic distortion, increased available fault current and power factor. Results also show that cloud cover has a dramatic and unpredictable effect on the output of a PV system. The preliminary analyses conclude that mitigation strategies are needed to overcome voltage deviations, unacceptable levels of harmonics, excessive fault current and low power factor. Mitigation strategies are proposed to control these issues predominantly through the use of high quality, made for purpose inverters. Results show that use of inverters with harmonic filtering reduces the level of harmonic injections to an acceptable level according to Australian standards. Furthermore, the configuration of inverters to supply active and reactive power assist in mitigating low power factor problems. Use of FACTS devices; SVC and STATCOM also reduces the harmonics and improve the power factor of the network, and finally, energy storage helps to smooth the power supply.Keywords: climate change, mitigation strategies, photovoltaic (PV), power quality
Procedia PDF Downloads 1688678 Human-Wildlife Conflicts in Urban Areas of Zimbabwe
Authors: Davie G. Dave, Prisca H. Mugabe, Tonderai Mutibvu
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Globally, HWCs are on the rise. Such is the case with urban areas in Zimbabwe, yet little has been documented about it. This study was done to provide insights into the occurrence of human-wildlife conflicts in urban areas. The study was carried out in Harare, Bindura, Masvingo, Beitbridge, and Chiredzi to determine the cause, nature, extent, and frequency of occurrence of HWC, to determine the key wildlife species involved in conflicts and management practices done to combat wildlife conflicts in these areas. Several sampling techniques encompassing multi-stage sampling, stratified random, purposive, and simple random sampling were employed for placing residential areas into three strata according to population density, selecting residential areas, and selecting actual participants. Data were collected through a semi-structured questionnaire and key informant interviews. The results revealed that property destruction and crop damage were the most prevalent conflicts. Of the 15 animals that were cited, snakes, baboons, and monkeys were associated with the most conflicts. The occurrence of HWCs was mainly attributed to the increase in both animal and human populations. To curtail these HWCs, the local people mainly used non-lethal methods, whilst lethal methods were used by authorities for some of the reported cases. The majority of the conflicts were seasonal and less severe. There were growing concerns by respondents on the issues of wildlife conflicts, especially in those areas that had primates, such as Warren Park in Harare and Limpopo View in Beitbridge. There are HWCs hotspots in urban areas, and to ameliorate this, suggestions are that there is a need for a multi-action approach that includes general awareness campaigns on HWCs and land use planning that involves the creation of green spaces to ease wildlife management.Keywords: human-wildlife conflicts, mitigation measures, residential areas, types of conflicts, urban areas
Procedia PDF Downloads 728677 Alterations of Molecular Characteristics of Polyethylene under the Influence of External Effects
Authors: Vigen Barkhudaryan
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The influence of external effects (γ-, UV–radiations, high temperature) in presence of air oxygen on structural transformations of low-density polyethylene (LDPE) have been investigated dependent on the polymers’ thickness, the intensity and the dose of external actions. The methods of viscosimetry, light scattering, turbidimetry and gelation measuring were used for this purpose. The comparison of influence of external effects on LDPE shows, that the destruction and cross-linking processes of macromolecules proceed simultaneously with all kinds of external effects. A remarkable growth of average molecular mass of LDPE along with the irradiation doses and heat treatment exposure growth was established. It was linear for the mass average molecular mass and at the initial doses is mainly the result of the increase of the macromolecular branching. As a result, the macromolecular hydrodynamic volumes have been changed, and therefore the dependence of viscosity average molecular mass on the doses was going through the minimum at initial doses. A significant change of molecular mass, sizes and shape of macromolecules of LDPE occurs under the influence of external effects. The influence is limited only by diffusion of oxygen during -irradiation and heat treatment. At UV–irradiation the influence is limited both by diffusion of oxygen and penetration of radiation. Consequently, the molecular transformations are deeper and evident in case of -irradiation, as soon as the polymer is transformed in a whole volume. It was also established, that the mechanism of molecular transformations in polymers from the surface layer distinctly differs from those of the sample deeper layer. A comparison of the results of these investigations allows us to conclude, that the mechanisms of influence of investigated external effects on polyethylene are similar.Keywords: cross-linking, destruction, high temperature, LDPE, γ-radiations, UV-radiations
Procedia PDF Downloads 3228676 Virtual Modelling of Turbulent Fibre Flow in a Low Consistency Refiner for a Sustainable and Energy Efficient Process
Authors: Simon Ingelsten, Anton Lundberg, Vijay Shankar, Lars-Olof Landström, Örjan Johansson
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The flow in a low consistency disc refiner is simulated with the aim of identifying flow structures possibly being of importance for a future study to optimise the energy efficiency in refining processes. A simplified flow geometry is used, where a single groove of a refiner disc is modelled. Two different fibre models are used to simulate turbulent fibre suspension flow in the groove. The first model is a Bingham viscoplastic fluid model where the fibre suspension is treated as a non-Newtonian fluid with a yield stress. The second model is a new model proposed in a recent study where the suspended fibres effect on flow is accounted for through a modelled orientation distribution function (ODF). Both models yielded similar results with small differences. Certain flow characteristics that were expected and that was found in the literature were identified. Some of these flow characteristics may be of importance in a future process to optimise the refiner geometry to increase the energy efficiency. Further study and a more detailed flow model is; however, needed in order for the simulations to yield results valid for quantitative use in such an optimisation study. An outline of the next steps in such a study is proposed.Keywords: disc refiner, fibre flow, sustainability, turbulence modelling
Procedia PDF Downloads 4128675 A Study on Reliability of Gender and Stature Determination by Odontometric and Craniofacial Anthropometric Parameters
Authors: Churamani Pokhrel, C. B. Jha, S. R. Niraula, P. R. Pokharel
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Human identification is one of the most challenging subjects that man has confronted. The determination of adult sex and stature are two of the four key factors (sex, stature, age, and race) in identification of an individual. Craniofacial and odontometric parameters are important tools for forensic anthropologists when it is not possible to apply advanced techniques for identification purposes. The present study provides anthropometric correlation of the parameters with stature and gender and also devises regression formulae for reconstruction of stature. A total of 312 Nepalese students with equal distribution of sex i.e., 156 male and 156 female students of age 18-35 years were taken for the study. Total of 10 parameters were measured (age, sex, stature, head circumference, head length, head breadth, facial height, bi-zygomatic width, mesio-distal canine width and inter-canine distance of both maxilla and mandible). Co-relation and regression analysis was done to find the association between the parameters. All parameters were found to be greater in males than females and each was found to be statistically significant. Out of total 312 samples, the best regressor for the determination of stature was head circumference and mandibular inter-canine width and that for gender was head circumference and right mandibular teeth. The accuracy of prediction was 83%. Regression equations and analysis generated from craniofacial and odontometric parameters can be a supplementary approach for the estimation of stature and gender when extremities are not available.Keywords: craniofacial, gender, odontometric, stature
Procedia PDF Downloads 1948674 Considering Partially Developed Artifacts in Change Impact Analysis Implementation
Authors: Nazri Kama, Sufyan Basri, Roslina Ibrahim
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It is important to manage the changes in the software to meet the evolving needs of the customer. Accepting too many changes causes delay in the completion and it incurs additional cost. One type of information that helps to make the decision is through change impact analysis. Current impact analysis approaches assume that all classes in the class artifact are completely developed and the class artifact is used as a source of analysis. However, these assumptions are impractical for impact analysis in the software development phase as some classes in the class artifact are still under development or partially developed that leads to inaccuracy. This paper presents a novel impact analysis approach to be used in the software development phase. The significant achievements of the approach are demonstrated through an extensive experimental validation using three case studies.Keywords: software development, impact analysis, traceability, static analysis.
Procedia PDF Downloads 6118673 Logistics Optimization: A Literature Review of Techniques for Streamlining Land Transportation in Supply Chain Operations
Authors: Danica Terese Valda, Segundo Villa III, Michiko Yasuda, Jomel Tagaro
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This study conducts a thorough literature review of logistics optimization techniques that aimed at improving the efficiency of supply chain operations. Logistics optimization encompasses key areas such as transportation management, inventory control, and distribution network design, each of which plays a critical role in streamlining supply chain performance. The review identifies mixed-integer linear programming (MILP) as a dominant method, widely used for its flexibility in handling complex logistics problems. Other methods like heuristic algorithms and combinatorial optimization also prove effective in solving large-scale logistics challenges. Furthermore, real-time data integration and advancements in simulation techniques are transforming the decision-making processes within supply chains, leading to more dynamic and responsive operations. The inclusion of sustainability goals, particularly in minimizing carbon emissions, has emerged as a growing trend in logistics optimization. This research highlights the need for integrated, holistic approaches that consider the interconnectedness of logistical components. The findings provide valuable insights to guide future research and practical applications, fostering more resilient and efficient supply chains.Keywords: logistics, techniques, supply chain, land transportation
Procedia PDF Downloads 248672 Examining the Extent and Magnitude of Food Security amongst Rural Farming Households in Nigeria
Authors: Ajibade T., Omotesho O. A., Ayinde O. E, Ajibade E. T., Muhammad-Lawal A.
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This study was carried out to examine the extent and magnitude of food security amongst farming rural households in Nigeria. Data used for this study was collected from a total of two hundred and forty rural farming households using a two-stage random sampling technique. The main tools of analysis for this study include descriptive statistics and a constructed food security index using the identification and aggregation procedure. The headcount ratio in this study reveals that 71% of individuals in the study area were food secure with an average per capita calorie and protein availability of 4,213.92kcal and 99.98g respectively. The aggregated household daily calorie availability and daily protein availability per capita were 3,634.57kcal and 84.08g respectively which happens to be above the food security line of 2,470kcal and 65g used in this study. The food insecure households fell short of the minimum daily per capita calorie and protein requirement by 2.1% and 24.9%. The study revealed that the area is food insecure due to unequal distribution of the available food amongst the sampled population. The study recommends that the households should empower themselves financially in order to enhance their ability to afford the food during both on and off seasons. Also, processing and storage of farm produce should be enhanced in order to improve on availability throughout the year.Keywords: farming household, food security, identification and aggregation, food security index
Procedia PDF Downloads 2938671 Mathematical Modelling of Blood Flow with Magnetic Nanoparticles as Carrier for Targeted Drug Delivery in a Stenosed Artery
Authors: Sreeparna Majee, G. C. Shit
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A study on targeted drug delivery is carried out in an unsteady flow of blood infused with magnetic NPs (nanoparticles) with an aim to understand the flow pattern and nanoparticle aggregation in a diseased arterial segment having stenosis. The magnetic NPs are supervised by the magnetic field which is significant for therapeutic treatment of arterial diseases, tumor and cancer cells and removing blood clots. Coupled thermal energy have also been analyzed by considering dissipation of energy because of the application of the magnetic field and the viscosity of blood. Simulation technique used to solve the mathematical model is vorticity-stream function formulations in the diseased artery. An elevation in SLP (Specific loss power) is noted in the aortic bloodstream when the agglomeration of nanoparticles is higher. This phenomenon has potential application in the treatment of hyperthermia. The study focuses on the lowering of WSS (Wall Shear Stress) with increasing particle concentration at the downstream of the stenosis which depicts the vigorous flow circulation zone. These low shear stress regions prolong the residing time of the nanoparticles carrying drugs which soaks up the LDL (Low Density Lipoprotein) deposition. Moreover, an increase in NP concentration enhances the Nusselt number which marks the increase of heat transfer from the arterial wall to the surrounding tissues to destroy tumor and cancer cells without affecting the healthy cells. The results have a significant influence in the study of medicine, to treat arterial diseases such as atherosclerosis without the need for surgery which can minimize the expenditures on cardiovascular treatments.Keywords: magnetic nanoparticles, blood flow, atherosclerosis, hyperthermia
Procedia PDF Downloads 1448670 An Encapsulation of a Navigable Tree Position: Theory, Specification, and Verification
Authors: Nicodemus M. J. Mbwambo, Yu-Shan Sun, Murali Sitaraman, Joan Krone
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This paper presents a generic data abstraction that captures a navigable tree position. The mathematical modeling of the abstraction encapsulates the current tree position, which can be used to navigate and modify the tree. The encapsulation of the tree position in the data abstraction specification avoids the use of explicit references and aliasing, thereby simplifying verification of (imperative) client code that uses the data abstraction. To ease the tasks of such specification and verification, a general tree theory, rich with mathematical notations and results, has been developed. The paper contains an example to illustrate automated verification ramifications. With sufficient tree theory development, automated proving seems plausible even in the absence of a special-purpose tree solver.Keywords: automation, data abstraction, maps, specification, tree, verification
Procedia PDF Downloads 1738669 Crickets as Social Business Model for Rural Women in Colombia
Authors: Diego Cruz, Helbert Arevalo, Diana Vernot
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In 2013, the Food and Agriculture Organization of the United Nations (FAO) said that insect production for food and feed could become an economic opportunity for rural women in developing countries. However, since then, just a few initiatives worldwide had tried to implement this kind of project in zones of tropical countries without previous experience in cricket production and insect human consumption, such as Colombia. In this project, ArthroFood company and the University of La Sabana join efforts to make a holistic multi-perspective analysis from biological, economic, culinary, and social sides of the Gryllodes sigillatus production by rural women of the municipality of La Mesa, Cundinamarca, Colombia. From a biological and economic perspective, G. sigillatus production in a 60m2 greenhouse was evaluated considering the effect of rearing density and substrates on final weight and length, developing time, survival rate, and proximate composition. Additionally, the production cost and labor hours were recorded for five months. On the other hand, from a socio- economic side, the intention of the rural women to implement cricket farms or micro-entrepreneurship around insect production was evaluated after developing ethnographies and empowerment, entrepreneurship, and cricket production workshops. Finally, the results of the elaboration of culinary recipes with cricket powder incorporating cultural aspects of the context of La Mesa, Cundinamarca, will be presented. This project represents Colombia's first attempt to create a social business model of cricket production involving rural women, academies, the private sector, and local authorities.Keywords: cricket production, developing country, edible insects, entrepreneurship, insect culinary recipes
Procedia PDF Downloads 1098668 Determination of the Factors Affecting Adjustment Levels of First Class Students at Elementary School
Authors: Sibel Yoleri
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In this research it is aimed to determine the adjustment of students who attend the first class at elementary school to school in terms of several variables. The study group of the research consists of 286 students (131 female, 155 male) who continue attending the first class of elementary school in 2013-2014 academic year, in the city center of Uşak. In the research, ‘Personal Information Form’ and ‘Walker-Mcconnell Scale of Social Competence and School Adjustment’ have been used as data collection tools. In the analysis of data, the t-test has been applied in the independent groups to determine whether the sampling group students’ scores of school adjustment differ according to the sex variable or not. For the evaluation of data identified as not showing normal distribution, Mann Whitney U test has been applied for paired comparison, Kruskal Wallis H test has been used for multiple comparisons. In the research, all the statistical processes have been evaluated bidirectional and the level of significance has been accepted as .05. According to the results gathered from the research, a meaningful difference could not been identified in the level of students’ adjustment to school in terms of sex variable. At the end of the research, it is identified that the adjustment level of the students who have started school at the age of seven is higher than the ones who have started school at the age of five and the adjustment level of the students who have preschool education before the elementary school is higher than the ones who have not taken.Keywords: starting school, preschool education, school adjustment, Walker-Mcconnell Scale
Procedia PDF Downloads 4938667 Numerical Study of Fluid Flow and Heat Transfer in the Spongy-Porous Media
Authors: Zeinab Sayed Abdel Rehim, M. A. Ziada, H. Salwa El-Deeb
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Numerical study of fluid flow, heat transfer and thermal energy storing or released in/from spongy-porous media to predict the thermal performance and characteristics of the porous media as packed bed system is presented in this work. This system is cylindrical channel filled with porous media (carbon foam). The system consists of working fluid (air) and spongy-porous medium; they act as the heat exchanger (heating or cooling modes) where thermal interaction occurs between the working fluid and the porous medium. The spongy-porous media are defined by the different type of porous medium employed in the storing or cooling modes. Two different porous media are considered in this study: Carbon foam, and Silicon rubber. The flow of the working fluid (air) is one dimensional in the axial direction from the top to downward and steady state conditions. The numerical results of transient temperature distribution for both working fluid and the spongy-porous medium phases and the amount of stored/realized heat inside/from the porous medium for each case with respect to the operating parameters and the spongy-porous media characteristics are illustrated.Keywords: fluid flow, heat transfer, numerical analysis, spongy-porous media, thermal performance, transient conditions
Procedia PDF Downloads 5508666 A Hydrometallurgical Route for the Recovery of Molybdenum from Mo-Co Spent Catalyst
Authors: Bina Gupta, Rashmi Singh, Harshit Mahandra
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Molybdenum is a strategic metal and finds applications in petroleum refining, thermocouples, X-ray tubes and in making of steel alloy owing to its high melting temperature and tensile strength. The growing significance and economic value of molybdenum have increased interest in the development of efficient processes aiming its recovery from secondary sources. Main secondary sources of Mo are molybdenum catalysts which are used for hydrodesulphurisation process in petrochemical refineries. The activity of these catalysts gradually decreases with time during the desulphurisation process as the catalysts get contaminated with toxic material and are dumped as waste which leads to environmental issues. In this scenario, recovery of molybdenum from spent catalyst is significant from both economic and environmental point of view. Recently ionic liquids have gained prominence due to their low vapour pressure, high thermal stability, good extraction efficiency and recycling capacity. Present study reports recovery of molybdenum from Mo-Co spent leach liquor using Cyphos IL 102[trihexyl(tetradecyl)phosphonium bromide] as an extractant. Spent catalyst was leached with 3 mol/L HCl and the leach liquor containing Mo-870 ppm, Co-341 ppm, Al-508 ppm and Fe-42 ppm was subjected to extraction step. The effect of extractant concentration on the leach liquor was investigated and almost 85% extraction of Mo was achieved with 0.05 mol/L Cyphos IL 102. Results of stripping studies revealed that 2 mol/L HNO3 can effectively strip 94% of the extracted Mo from the loaded organic phase. McCabe-Thiele diagrams were constructed to determine the number of stages required for quantitative extraction and stripping of molybdenum and were confirmed by counter current simulation studies. According to McCabe-Thiele extraction and stripping isotherms, two stages are required for quantitative extraction and stripping of molybdenum at A/O= 1:1. Around 95.4% extraction of molybdenum was achieved in two stage counter current at A/O= 1:1 with negligible extraction of Co and Al. However, iron was coextracted and removed from the loaded organic phase by scrubbing with 0.01 mol/L HCl. Quantitative stripping (~99.5 %) of molybdenum was achieved with 2.0 mol/L HNO3 in two stages at O/A=1:1. Overall ~95.0% molybdenum with 99 % purity was recovered from Mo-Co spent catalyst. From the strip solution, MoO3 was obtained by crystallization followed by thermal decomposition. The product obtained after thermal decomposition was characterized by XRD, FE-SEM and EDX techniques. XRD peaks of MoO3correspond to molybdite Syn-MoO3 structure. FE-SEM depicts the rod like morphology of synthesized MoO3. EDX analysis of MoO3 shows 1:3 atomic percentage of molybdenum and oxygen. The synthesised MoO3 can find application in gas sensors, electrodes of batteries, display devices, smart windows, lubricants and as catalyst.Keywords: cyphos IL 102, extraction, Mo-Co spent catalyst, recovery
Procedia PDF Downloads 2698665 Superficial Metrology of Organometallic Chemical Vapour Deposited Undoped ZnO Thin Films on Stainless Steel and Soda-Lime Glass Substrates
Authors: Uchenna Sydney Mbamara, Bolu Olofinjana, Ezekiel Oladele B. Ajayi
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Elaborate surface metrology of undoped ZnO thin films, deposited by organometallic chemical vapour deposition (OMCVD) technique at different precursor flow rates, was carried out. Dicarbomethyl-zinc precursor was used. The films were deposited on AISI304L steel and soda-lime glass substrates. Ultraviolet-visible-near-infrared (UV-Vis-NIR) spectroscopy showed that all the thin films were over 80% transparent, with an average bandgap of 3.39 eV, X-ray diffraction (XRD) results showed that the thin films were crystalline with a hexagonal structure, while Rutherford backscattering spectroscopy (RBS) results identified the elements present in each thin film as zinc and oxygen in the ratio of 1:1. Microscope and contactless profilometer results gave images with characteristic colours. The profilometer also gave the surface roughness data in both 2D and 3D. The asperity distribution of the thin film surfaces was Gaussian, while the average fractal dimension Da was in the range of 2.5 ≤ Da. The metrology proved the surfaces good for ‘touch electronics’ and coating mechanical parts for low friction.Keywords: undoped ZnO, precursor flow rate, OMCVD, thin films, surface texture, tribology
Procedia PDF Downloads 658664 When the Poor Do Not Matter: Environmental Justice and Solid Waste Management in Kinshasa, the Democratic Republic of Congo
Authors: N. S. Kubanza, D. Simatele, D. K. Das
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The purpose of this paper is to understand the urban environmental problems in Kinshasa and the consequences of these for the poor. This paper particularly examines the concept of environmental injustice in solid waste management in Kinshasa, the capital of the Democratic Republic of Congo (DRC). The urban low-income communities in Kinshasa face multiple consequences of poor solid waste management associated with unhealthy living conditions. These situations stemmed from overcrowding, poor sanitary, accumulation of solid waste, resulting in the prevalence of water and air borne diseases. Using a mix of reviewed archival records, scholarly literature, a semi-structured interview conducted with the local community members and qualitative surveys among stakeholders; it was found that solid waste management challenge in Kinshasa is not only an environmental and health risk issues, but also, a problem that generates socio-spatial disparities in the distribution of the solid waste burden. It is argued in the paper that the urban poor areas in Kinshasa are often hardest affected by irregularities of waste collection. They lack sanitary storage capacities and have undermined organizational capacity for collective action within solid waste management. In view of these observations, this paper explores mechanisms and stakeholders’ engagement necessary to lessen environmental injustice in solid waste management (SWM) in Kinshasa.Keywords: environmental justice, solid waste management, urban environmental problems, urban poor
Procedia PDF Downloads 266