Search results for: energy performance certificate EPBD
3019 An Exploratory Study to Understand the Economic Opportunities from Climate Change
Authors: Sharvari Parikh
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Climate change has always been looked upon as a threat. Increased use of fossil fuels, depletion of bio diversity, certain human activities, rising levels of Greenhouse Gas (GHG) emissions are the factors that have caused climate change. Climate change is creating new risks and aggravating the existing ones. The paper focuses on breaking the stereotypical perception of climate change and draws attention towards the constructive side of it. Researches around the world have concluded that climate change has provided us with many untapped opportunities. The next 15 years will be crucial, as it is in our hands whether we are able to grab these opportunities or just let the situation get worse. The world stands at a stage where we cannot think of making a choice between averting climate change and promoting growth and development. In fact, the solution to climate change itself has got economic opportunities. The data evidences from the paper show how we can create the opportunity to improve the lives of the world’s population at large through structural change which will promote environment friendly investments. Rising Investment in green energy and increased demand of climate friendly products has got ample of employment opportunities. Old technologies and machinery which are employed today lack efficiency and demand huge maintenance because of which we face high production cost. This can be drastically brought down by adaptation of Green technologies which are more accessible and affordable. Overall GDP of the world has been heavily affected in aggravating the problems arising out of increasing weather problems. Shifting to green economy can not only eliminate these costs but also build a sound economy. Accelerating the economy in direction of low-carbon future can lessen the burdens such as subsidies for fossil fuels, several public debts, unemployment, poverty, reduce healthcare expenses etc. It is clear that the world will be dragged into the ‘Darker phase’ if the current trends of fossil fuels and carbon are being consumed. Switching to Green economy is the only way in which we can lift the world from darker phase. Climate change has opened the gates for ‘Green and Clean economy’. It will also bring countries of the world together in achieving the common goal of Green Economy.Keywords: climate change, economic opportunities, green economy, green technology
Procedia PDF Downloads 2473018 Comparison of Fatty Acids Composition of Three Commercial Fish Species Farmed in the Adriatic Sea
Authors: Jelka Pleadin, Greta Krešić, Tina Lešić, Ana Vulić, Renata Barić, Tanja Bogdanović, Dražen Oraić, Ana Legac, Snježana Zrnčić
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Fish has been acknowledged as an integral component of a well-balanced diet, providing a healthy source of energy, high-quality proteins, vitamins, essential minerals and, especially, n-3 long-chain polyunsaturated fatty acids (n-3 LC PUFA), mainly eicosapentaenoic acid (20:5 n-3 EPA), and docosahexaenoicacid, (22:6 n-3 DHA), whose pleiotropic effects in terms of health promotion and disease prevention have been increasingly recognised. In this study, the fatty acids composition of three commercially important farmed fish species: sea bream (Sparus aurata), sea bass (Dicentrarchus labrax) and dentex (Dentex dentex) was investigated. In total, 60 fish samples were retrieved during 2015 (n = 30) and 2016 (n = 30) from different locations in the Adriatic Sea. Methyl esters of fatty acids were analysed using gas chromatography (GC) with flame ionization detection (FID). The results show that the most represented fatty acid in all three analysed species is oleic acid (C18:1n-9, OA), followed by linoleic acid (C18:2n-6, LA) and palmitic acid (C16:0, PA). Dentex was shown to have two to four times higher eicosapentaenoic (EPA) and docosahexaenoic (DHA) acid content as compared to sea bream and sea bass. The recommended n-6/n-3 ratio was determined in all fish species but obtained results pointed to statistically significant differences (p < 0.05) in fatty acid composition among the analysed fish species and their potential as a dietary source of valuable fatty acids. Sea bass and sea bream had a significantly higher proportion of n-6 fatty acids, while dentex had a significantly higher proportion of n-3 (C18:4n-3, C20:4n-3, EPA, DHA) fatty acids. A higher hypocholesterolaemic and hypercholesterolaemic fatty acids (HH) ratio was determined for sea bass and sea bream, which comes as the consequence of a lower share of SFA determined in these two species in comparison to dentex. Since the analysed fish species vary in their fatty acids composition consumption of diverse fish species would be advisable. Based on the established lipid quality indicators, dentex, a fish species underutilised by the aquaculture, seems to be a highly recommendable and important source of fatty acids recommended to be included into the human diet.Keywords: dentex, fatty acids, farmed fish, sea bass, sea bream
Procedia PDF Downloads 3973017 Genetic Diversity Analysis of Pearl Millet (Pennisetum glaucum [L. R. Rr.]) Accessions from Northwestern Nigeria
Authors: Sa’adu Mafara Abubakar, Muhammad Nuraddeen Danjuma, Adewole Tomiwa Adetunji, Richard Mundembe, Salisu Mohammed, Francis Bayo Lewu, Joseph I. Kiok
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Pearl millet is the most drought tolerant of all domesticated cereals, is cultivated extensively to feed millions of people who mainly live in hash agroclimatic zones. It serves as a major source of food for more than 40 million smallholder farmers living in the marginal agricultural lands of Northern Nigeria. Pearl millet grain is more nutritious than other cereals like maize, is also a principal source of energy, protein, vitamins, and minerals for millions of poorest people in the regions where it is cultivated. Pearl millet has recorded relatively little research attention compared with other crops and no sufficient work has analyzed its genetic diversity in north-western Nigeria. Therefore, this study was undertaken with the objectives to analyze the genetic diversity of pearl millet accessions using SSR marker and to analyze the extent of evolutionary relationship among pearl millet accessions at the molecular level. The result of the present study confirmed diversity among accessions of pearl millet in the study area. Simple Sequence Repeats (SSR) markers were used for genetic analysis and evolutionary relationship of the accessions of pearl millet. To analyze the level of genetic diversity, 8 polymorphic SSR markers were used to screen 69 accessions collected based on three maturity periods. SSR markers result reveal relationships among the accessions in terms of genetic similarities, evolutionary and ancestral origin, it also reveals a total of 53 alleles recorded with 8 microsatellites and an average of 6.875 per microsatellite, the range was from 3 to 9 alleles in PSMP2248 and PSMP2080 respectively. Moreover, both the factorial analysis and the dendrogram of phylogeny tree grouping patterns and cluster analysis were almost in agreement with each other that diversity is not clustering according to geographical patterns but, according to similarity, the result showed maximum similarity among clusters with few numbers of accessions. It has been recommended that other molecular markers should be tested in the same study area.Keywords: pearl millet, genetic diversity, simple sequence repeat (SSR)
Procedia PDF Downloads 2763016 Comparison of Soil Test Extractants for Determination of Available Soil Phosphorus
Authors: Violina Angelova, Stefan Krustev
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The aim of this work was to evaluate the effectiveness of different soil test extractants for the determination of available soil phosphorus in five internationally certified standard soils, sludge and clay (NCS DC 85104, NCS DC 85106, ISE 859, ISE 952, ISE 998). The certified samples were extracted with the following methods/extractants: CaCl₂, CaCl₂ and DTPA (CAT), double lactate (DL), ammonium lactate (AL), calcium acetate lactate (CAL), Olsen, Mehlich 3, Bray and Kurtz I, and Morgan, which are commonly used in soil testing laboratories. The phosphorus in soil extracts was measured colorimetrically using Spectroquant Pharo 100 spectrometer. The methods used in the study were evaluated according to the recovery of available phosphorus, facility of application and rapidity of performance. The relationships between methods are examined statistically. A good agreement of the results from different soil test was established for all certified samples. In general, the P values extracted by the nine extraction methods significantly correlated with each other. When grouping the soils according to pH, organic carbon content and clay content, weaker extraction methods showed analogous trends; also among the stronger extraction methods, common tendencies were found. Other factors influencing the extraction force of the different methods include soil: solution ratio, as well as the duration and power of shaking the samples. The mean extractable P in certified samples was found to be in the order of CaCl₂ < CAT < Morgan < Bray and Kurtz I < Olsen < CAL < DL < Mehlich 3 < AL. Although the nine methods extracted different amounts of P from the certified samples, values of P extracted by the different methods were strongly correlated among themselves. Acknowledgment: The financial support by the Bulgarian National Science Fund Projects DFNI Н04/9 and DFNI Н06/21 are greatly appreciated.Keywords: available soil phosphorus, certified samples, determination, soil test extractants
Procedia PDF Downloads 1553015 Study on Science and Technology Resources Coordinated Development and Innovation of Beijing-Tianjin-Hebei Region
Authors: Hong Zhang, Runlian Miao, Min Zhang
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Coordinated development of Beijing-Tianjin-Hebei region is of great importance and has been emphasized by the government in recent years. Beijing-Tianjin-Hebei region accumulates a large part of S&T resources of the whole country and boasts the most influential achievements. In order to improve innovation capability of the region, universities, research institutions and enterprises from Beijing, Tianjin and Hebei have cooperated in many forms, but technological innovation is not so satisfactory due to unbalanced allocation, poor sharing and low utilization efficiency of S&T resources. Therefore, it’s very necessary to promote resources sharing, optimize their overall layout, and enhance their innovation performance, which can further deepen coordination development of the region. This study focuses on S&T resources with the methods of documents research plus field investigation and qualitative research combing plus quantitive research. It starts from the macro background of promoting coordinated development of Beijing-Tianjin-Hebei region and arrives at improving regional innovation capability. Firstly, the author makes a literature review on coordinated development of Beijing-Tianjin-Hebei region and summarizes that coordinated development has been carried forward in the major fields which lay foundation for regional innovation; secondly, analyzes current S&T resources distribution and coordinated innovation by taking key industries as the examples; based on analysis of the status quo of resources sharing and innovation in the region, the author points out problems and obstacles that holdbacks coordinated innovation of the region and at last raises some suggestions to resources sharing and regional innovation. It reaches the conclusion that an efficient management mechanism, market laws, favorable environment, model innovation and incentive measures can help to accelerate resources sharing and regional innovation in the region.Keywords: Beijing-Tianjin-Hebei region, coordinated development, innovation, S&T resources
Procedia PDF Downloads 3093014 Multiaxial Fatigue Analysis of a High Performance Nickel-Based Superalloy
Authors: P. Selva, B. Lorraina, J. Alexis, A. Seror, A. Longuet, C. Mary, F. Denard
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Over the past four decades, the fatigue behavior of nickel-based alloys has been widely studied. However, in recent years, significant advances in the fabrication process leading to grain size reduction have been made in order to improve fatigue properties of aircraft turbine discs. Indeed, a change in particle size affects the initiation mode of fatigue cracks as well as the fatigue life of the material. The present study aims to investigate the fatigue behavior of a newly developed nickel-based superalloy under biaxial-planar loading. Low Cycle Fatigue (LCF) tests are performed at different stress ratios so as to study the influence of the multiaxial stress state on the fatigue life of the material. Full-field displacement and strain measurements as well as crack initiation detection are obtained using Digital Image Correlation (DIC) techniques. The aim of this presentation is first to provide an in-depth description of both the experimental set-up and protocol: the multiaxial testing machine, the specific design of the cruciform specimen and performances of the DIC code are introduced. Second, results for sixteen specimens related to different load ratios are presented. Crack detection, strain amplitude and number of cycles to crack initiation vs. triaxial stress ratio for each loading case are given. Third, from fractographic investigations by scanning electron microscopy it is found that the mechanism of fatigue crack initiation does not depend on the triaxial stress ratio and that most fatigue cracks initiate from subsurface carbides.Keywords: cruciform specimen, multiaxial fatigue, nickel-based superalloy
Procedia PDF Downloads 2993013 One Pot Synthesis of Ultrasmall NiMo Catalysts Supported on Amorphous Alumina with Enhanced type 2 Sites for Hydrodesulfurization Reaction: A Combined Experimental and Theoretical Study
Authors: Shalini Arora, Sri Sivakumar
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The deep removal of high molecular weight sulphur compounds (e.g., 4,6, dimethyl dibenzothiophene) is challenging due to their steric hindrance. Hydrogenation desulfurization (HYD) pathway is the main pathway to remove these sulfur compounds, and it is mainly governed by the number of type 2 sites. The formation of type 2 sites can be enhanced by modulating the pore structure and the interaction between the active metal and support. To this end, we report the enhanced HDS catalytic activity of ultrasmall NiMo supported on amorphous alumina (A-Al₂O₃) catalysts by one pot colloidal synthesis method followed by calcination and sulfidation. The amorphous alumina (A-Al₂O₃) was chosen as the support due to its lower surface energy, better physicochemical properties, and enhanced acidic sites (due to the dominance of tetra and penta coordinated [Al] sites) than crystalline alumina phase. At 20% metal oxide composition, NiMo supported on A-Al₂O₃ catalyst showed 1.4 and 1.2 times more reaction rate constant and turn over frequency (TOF) respectively than the conventional catalyst (wet impregnated NiMo catalysts) for HDS reaction of dibenzothiophene reactant molecule. A-Al₂O₃ supported catalysts represented enhanced type 2 sites formation (because this catalystpossesses higher sulfidation degree (80%) and NiMoS sites (19.3 x 10¹⁷ sites/mg) with desired optimum stacking degree (2.5) than wet impregnated catalyst at same metal oxide composition 20%) along with higher active metal dispersion, Mo edge site fraction. The experimental observations were also supported by DFT simulations. Lower heat of adsorption (< 4.2 ev for MoS2 interaction and < 3.15 ev for Ni doped MoS2 interaction) values for A-Al₂O₃ confirmed the presence of weaker metal-support interaction in A-Al₂O₃ in contrast to crystalline ℽ-Al₂O3. The weak metal-support interaction for prepared catalysts clearly suggests the higher formation of type 2 sites which leads to higher catalytic activity for HDS reaction.Keywords: amorphous alumina, colloidal, desulfurization, metal-support interaction
Procedia PDF Downloads 2723012 Effects of 8-Week Bee Bread Supplementation on Isokinetic Muscular Strength and Power in Young Athletes
Authors: Fadzel Wong Chee Ping, Chee Keong Chen, Foong Kiew Ooi, Mahaneem Mohamed
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Introduction: To date, information on the effects of bee bread supplementation on isokinetic muscular performance are lacking. Therefore, this study was carried out to investigate the effects of 8-week bee bread supplementation on isokinetic muscular strength and power in young athletes. Methodology: Twelve male athletes (age: 24.0±1.8 years; BMI: 22.3 ± 1.3 kg.m-2; VO2max: 52.0 ± 2.8 mL.kg-1.min-1) were recruited in this randomised double blind, placebo-controlled crossover study. Participants consumed either bee bread at a dosage of 20 g.d-1 or placebo for 8 weeks. An isokinetic dynamometer was used to measure participants’ lower limb muscular strength and power prior (pre-test) and post (post-test) 8 weeks of experimental period. Testing angular velocities were set at 180o.s-1 and 300o.s-1 to determine knee flexion and extension muscular peak torque (an indicator of muscular strength) and average power of the participants. Statistical analyses were performed using ANOVA with repeated measures. Results: Isokinetic knee extension peak torque and average power at 180o.s-1, and isokinetic knee flexion peak torque and average power at 180o.s-1 were significantly (p<0.05) higher at post-test compared to pre-test with bee bread supplementation. However, significant differences were not observed in the measured parameters between pre- and post-test with placebo supplementation. Conclusion: Supplementation of bee bread for 8 weeks at a dosage of 20 g daily increased some of the measured isokinetic muscular strength and power parameters in young athletes.Keywords: bee bread, isokinetic, power, strength
Procedia PDF Downloads 2603011 Analysis of the Vibration Behavior of a Small-Scale Wind Turbine Blade under Johannesburg Wind Speed
Authors: Tolulope Babawarun, Harry Ngwangwa
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The wind turbine blade may sustain structural damage from external loads such as high winds or collisions, which could compromise its aerodynamic efficiency. The wind turbine blade vibrates at significant intensities and amplitudes under these conditions. The effect of these vibrations on the dynamic flow field surrounding the blade changes the forces operating on it. The structural dynamic analysis of a small wind turbine blade is considered in this study. It entails creating a finite element model, validating the model, and doing structural analysis on the verified finite element model. The analysis is based on the structural reaction of a small-scale wind turbine blade to various loading sources. Although there are many small-scale off-shore wind turbine systems in use, only preliminary structural analysis is performed during design phases; these systems' performance under various loading conditions as they are encountered in real-world situations has not been properly researched. This will allow us to record the same Equivalent von Mises stress and deformation that the blade underwent. A higher stress contour was found to be more concentrated near the middle span of the blade under the various loading scenarios studied. The highest stress that the blade in this study underwent is within the range of the maximum stress that blade material can withstand. The maximum allowable stress of the blade material is 1,770 MPa. The deformation of the blade was highest at the blade tip. The critical speed of the blade was determined to be 4.3 Rpm with a rotor speed range of 0 to 608 Rpm. The blade's mode form under loading conditions indicates a bending mode, the most prevalent of which is flapwise bending.Keywords: ANSYS, finite element analysis, static loading, dynamic analysis
Procedia PDF Downloads 923010 Perception Towards Using E-learning with Stem Students Whose Programs Require Them to Attend Practical Sections in Laboratories during Covid-19
Authors: Youssef A. Yakoub, Ramy M. Shaaban
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Covid-19 has changed and affected the whole world dramatically in a new way that the entire world, even scientists, have not imagined before. The educational institutions around the world have been fighting since Covid-19 hit the world last December to keep the educational process unchanged for all students. E-learning was a must for almost all US universities during the pandemic. It was specifically more challenging to use eLearning instead of regular classes among students who take practical education. The aim of this study is to examine the perception of STEM students towards using eLearning instead of traditional methods during their practical study. Focus groups of STEM students studying at a western Pennsylavian, mid-size university were interviewed. Semi-structured interviews were designed to get an insight on students’ perception towards the alternative educational methods they used in the past seven months. Using convenient sampling, four students were chosen from different STEM fields: science of physics, technology, electrical engineering, and mathematics. The interview was primarily about the extent to which these students were satisfied, and their educational needs were met through distance education during the pandemic. The interviewed students were generally able to do a satisfactory performance during their virtual classes, but they were not satisfied enough with the learning methods. The main challenges they faced included the inability to have real practical experience, insufficient materials posted by the faculty, and some technical problems associated with their study. However, they reported they were satisfied with the simulation programs they had. They reported these simulations provided them with a good alternative to their traditional practical education. In conclusion, this study highlighted the challenges students face during the pandemic. It also highlighted the various learning tools students see as good alternatives to their traditional education.Keywords: eLearning, STEM education, COVID-19 crisis, online practical training
Procedia PDF Downloads 1403009 Emotional Intelligence as a Predictor of Job Satisfaction in the Nigerian Construction Industry
Authors: Adedayo Johnson Ogungbile, Ayodeji Emmanuel Oke, Oluwaseyi Alabi Awodele
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This study examines the role of emotional intelligence (EI) as a predictor of job satisfaction within the Nigerian construction industry. Utilizing a methodology that combines mean comparison and correlation analysis, the research explores how EI influences job satisfaction across diverse demographic and professional categories. The construction industry, known for its dynamic and often challenging work environment, provides a unique context to investigate how EI contributes to employee satisfaction. The findings reveal a significant positive correlation between EI and job satisfaction across the industry. Gender-based analysis shows that male employees typically report higher EI and job satisfaction levels compared to their female counterparts, although the impact of EI on job satisfaction is more substantial among women. The study further explores the relationship between trait EI and specific job satisfaction categories, identifying a general positive association with overall job satisfaction but not with supervisor-related satisfaction. Employees are categorized into four EI classes, consistently showing that higher EI levels correspond to greater job satisfaction. These findings align with existing literature, underscoring EI's pivotal role in enhancing job satisfaction in the construction sector. The study concludes that fostering EI among construction industry professionals can lead to improved job satisfaction and performance. Consequently, organizations are encouraged to integrate EI development into their professional growth programs to cultivate a more satisfied and effective workforce. In essence, this research highlights the importance of EI as a key predictor of job satisfaction in the Nigerian construction industry, providing valuable insights for both industry stakeholders and researchers into the benefits of prioritizing emotional intelligence in this high-stakes environment.Keywords: emotional intelligence, job satisfaction, construction industry, workforce productivity, demographics
Procedia PDF Downloads 263008 Key Parameters for Controlling Swell of Expansive Soil-Hydraulic Cement Admixture
Authors: Aung Phyo Kyaw, Kuo Chieh Chao
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Expansive soils are more complicated than normal soils, although the soil itself is not very complicated. When evaluating foundation performance on expansive soil, it is important to consider soil expansion. The primary focus of this study is on hydraulic cement and expansive soil mixtures, and the research aims to identify key parameters for controlling the swell of the expansive soil-hydraulic cement mixture. Treatment depths can be determined using hydraulic cement ratios of 4%, 8%, 12%, and 15% for treating expansive soil. To understand the effect of hydraulic cement percentages on the swelling of expansive soil-hydraulic admixture, performing the consolidation-swell test σ''ᶜˢ is crucial. This investigation primarily focuses on consolidation-swell tests σ''ᶜˢ, although the heave index Cₕ is also needed to determine total heave. The heave index can be measured using the percent swell in the specific inundation stress in both the consolidation-swell test and the constant-volume test swelling pressure. Obtaining the relationship between swelling pressure and σ''ᶜⱽ determined from the "constant volume test" is useful in predicting heave from a single oedometer test. The relationship between σ''ᶜˢ and σ''ᶜⱽ is based on experimental results of expansive soil behavior and facilitates heave prediction for each soil. In this method, the soil property "m" is used as a parameter, and common soil property tests include compaction, particle size distribution, and the Atterberg limit. The Electricity Generating Authority of Thailand (EGAT) provided the soil sample for this study, and all laboratory testing is performed according to American Society for Testing and Materials (ASTM) standards.Keywords: expansive soil, swelling pressure, total heave, treatment depth
Procedia PDF Downloads 893007 The Effect of Silanization on Alumina for Improving the Compatibility with Poly(Methacrylic Acid) Matrix for Dental Restorative Materials
Authors: Andrei Tiberiu Cucuruz, Ecaterina Andronescu, Cristina Daniela Ghitulica, Andreia Cucuruz
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In modern dentistry, the application of resin-based composites continues to increase and in the majority of countries has completely replaced mercury amalgams. Alumina (Al2O3) is a representative bioinert ceramic with a variety of applications in industry as well as in medicine. Alumina has the potential to improve electrical resistivity and thermal conductivity of polymers. The application of poly(methacrylic acid) (PMAA) in medicine was poorly investigated in the past but can lead to good results by the incorporation of alumina particles that can bring bioinertness to the composite. However, because of the differences related to chemical bonding of these materials, the interaction is very weak at the interface leading to no significant values in practical situations. The aim of this work was to modify the structure of alumina with silane coupling agents and to study the influence of silanization on the physicomechanical properties of the resulting composite materials. Two silanes were used in this study: 3-aminopropyl-trimethoxysilane (APTMS) and dichlorodimethylsilane (DCDMS). Both silanes proved to have a significant effect on the overall performance of composites by establishing bonds with the polymer matrix and the filler. All these improvements in dental adhesive systems made for bonding resin composites to tooth structure have enhanced the clinical application of polymeric restorative materials to the position that they are now considered the material of choice for esthetic restoration.Keywords: alumina, compressive strength, dental materials, silane coupling agents, poly(methacrylic acid)
Procedia PDF Downloads 3543006 From Synthesis to Application of Photovoltaic Perovskite Nanowires
Authors: László Forró
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The organolead halide perovskite CH3NH3PbI3 and its derivatives are known to be very efficient light harvesters revolutionizing the field of solid-state solar cells. The major research area in this field is photovoltaic device engineering although other applications are being explored, as well. Recently, we have shown that nanowires of this photovoltaic perovskite can be synthesized which in association with carbon nanostructures (carbon nanotubes and graphene) make outstanding composites with rapid and strong photo-response. They can serve as conducting electrodes, or as central components of detectors. The performance of several miniature devices based on these composite structures will be demonstrated. Our latest findings on the guided growth of perovskite nanowires by solvatomorph graphoepitaxy will be presented. This method turned out to be a fairly simple approach to overcome the spatially random surface nucleation. The process allows the synthesis of extremely long (centimeters) and thin (a few nanometers) nanowires with a morphology defined by the shape of nanostructured open fluidic channels. This low-temperature solution-growth method could open up an entirely new spectrum of architectural designs of organometallic-halide-perovskite-based heterojunctions and tandem solar cells, LEDs and other optoelectronic devices. Acknowledgment: This work is done in collaboration with Endre Horvath, Massimo Spina, Alla Arakcheeva, Balint Nafradi, Eric Bonvin1, Andrzej Sienkievicz, Zsolt Szekrenyes, Hajnalka Tohati, Katalin Kamaras, Eduard Tutis, Laszlo Mihaly and Karoly Holczer The research is supported by the ERC Advanced Grant (PICOPROP670918).Keywords: photovoltaics, perovskite, nanowire, photodetector
Procedia PDF Downloads 3593005 Effect of Dietary Waste Date Meal (Phoneix dactylifera) on Chemical Body Composition, Nutrition Value and Fatty Acids Profile of Fingerling Common Carp (Cyprinus carpio)
Authors: Mehrdad Kamali-Sanzighi, Maziar Kamali-sanzighi
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Effect of waste date meal (WDM) addition to the diet on body chemical composition and fatty acids profile of fingerling cyprinus carpio were evaluated. Four treatments with 3 replication such as control treatment (no additional WDM; T1), 5% WDM (50 gr/kg; T2), 10% WDM (100 gr/kg; T3) and 15% WDM (150 gr/kg; T4) were done. 168 fish with initial weight of 2.48±0.06 gr were fed 3 times per day according to 5 % of fish body weight for 12 weeks. The body composition results showed that there is no significant differences between treatments (P>0.05). All of Fatty acids profile parameters show significant differences between different treatments (P<0.05). Although, the highest value of MUFA+PUFA, PUFA/SFA, MUFA+PUFA/SFA, W3, EPA+DHA parameters belong to control treatment (T1) and 5% WDM treatment (T2) had lowest value of MUFA, PUFA, MUFA+PUFA, PUFA/SFA, MUFA+PUFA/SFA, W3, W3/W6, DHA/EPA and EPA+DHA parameters except of SFA and W6/W3 that show highest value than other treatments. Atherogenic index (AI) had no significant differences between different treatments (P>0.05) but Thrombogenic index (TI) had significant differences between different experimental treatments (P<0.05). The 5% WDM and control treatment show highest and lowest values. Generally, treatments of 10 and 15% WDM (T3-T4) had moderate performance than the other experimental treatments. Finally, addition of WDM to common carp fingerlings diets help to insignificant improvement of chemical body composition and the saturated and unsaturated fatty acids profile of them were significant.Keywords: waste, date, common carp, nutrition value
Procedia PDF Downloads 943004 Computer Aided Shoulder Prosthesis Design and Manufacturing
Authors: Didem Venus Yildiz, Murat Hocaoglu, Murat Dursun, Taner Akkan
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The shoulder joint is a more complex structure than the hip or knee joints. In addition to the overall complexity of the shoulder joint, two different factors influence the insufficient outcome of shoulder replacement: the shoulder prosthesis design is far from fully developed and it is difficult to place these shoulder prosthesis due to shoulder anatomy. The glenohumeral joint is the most complex joint of the human shoulder. There are various treatments for shoulder failures such as total shoulder arthroplasty, reverse total shoulder arthroplasty. Due to its reverse design than normal shoulder anatomy, reverse total shoulder arthroplasty has different physiological and biomechanical properties. Post-operative achievement of this arthroplasty is depend on improved design of reverse total shoulder prosthesis. Designation achievement can be increased by several biomechanical and computational analysis. In this study, data of human both shoulders with right side fracture was collected by 3D Computer Tomography (CT) machine in dicom format. This data transferred to 3D medical image processing software (Mimics Materilise, Leuven, Belgium) to reconstruct patient’s left and right shoulders’ bones geometry. Provided 3D geometry model of the fractured shoulder was used to constitute of reverse total shoulder prosthesis by 3-matic software. Finite element (FE) analysis was conducted for comparison of intact shoulder and prosthetic shoulder in terms of stress distribution and displacements. Body weight physiological reaction force of 800 N loads was applied. Resultant values of FE analysis was compared for both shoulders. The analysis of the performance of the reverse shoulder prosthesis could enhance the knowledge of the prosthetic design.Keywords: reverse shoulder prosthesis, biomechanics, finite element analysis, 3D printing
Procedia PDF Downloads 1613003 Experimental Study on Two-Step Pyrolysis of Automotive Shredder Residue
Authors: Letizia Marchetti, Federica Annunzi, Federico Fiorini, Cristiano Nicolella
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Automotive shredder residue (ASR) is a mixture of waste that makes up 20-25% of end-of-life vehicles. For many years, ASR was commonly disposed of in landfills or incinerated, causing serious environmental problems. Nowadays, thermochemical treatments are a promising alternative, although the heterogeneity of ASR still poses some challenges. One of the emerging thermochemical treatments for ASR is pyrolysis, which promotes the decomposition of long polymeric chains by providing heat in the absence of an oxidizing agent. In this way, pyrolysis promotes the conversion of ASR into solid, liquid, and gaseous phases. This work aims to improve the performance of a two-step pyrolysis process. After the characterization of the analysed ASR, the focus is on determining the effects of residence time on product yields and gas composition. A batch experimental setup that reproduces the entire process was used. The setup consists of three sections: the pyrolysis section (made of two reactors), the separation section, and the analysis section. Two different residence times were investigated to find suitable conditions for the first sample of ASR. These first tests showed that the products obtained were more sensitive to residence time in the second reactor. Indeed, slightly increasing residence time in the second reactor managed to raise the yield of gas and carbon residue and decrease the yield of liquid fraction. Then, to test the versatility of the setup, the same conditions were applied to a different sample of ASR coming from a different chemical plant. The comparison between the two ASR samples shows that similar product yields and compositions are obtained using the same setup.Keywords: automotive shredder residue, experimental tests, heterogeneity, product yields, two-step pyrolysis
Procedia PDF Downloads 1323002 Urban Transport Demand Management Multi-Criteria Decision Using AHP and SERVQUAL Models: Case Study of Nigerian Cities
Authors: Suleiman Hassan Otuoze, Dexter Vernon Lloyd Hunt, Ian Jefferson
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Urbanization has continued to widen the gap between demand and resources available to provide resilient and sustainable transport services in many fast-growing developing countries' cities. Transport demand management is a decision-based optimization concept for both benchmarking and ensuring efficient use of transport resources. This study assesses the service quality of infrastructure and mobility services in the Nigerian cities of Kano and Lagos through five dimensions of quality (i.e., Tangibility, Reliability, Responsibility, Safety Assurance and Empathy). The methodology adopts a hybrid AHP-SERVQUAL model applied on questionnaire surveys to gauge the quality of satisfaction and the views of experts in the field. The AHP results prioritize tangibility, which defines the state of transportation infrastructure and services in terms of satisfaction qualities and intervention decision weights in the two cities. The results recorded ‘unsatisfactory’ indices of quality of performance and satisfaction rating values of 48% and 49% for Kano and Lagos, respectively. The satisfaction indices are identified as indicators of low performances of transportation demand management (TDM) measures and the necessity to re-order priorities and take proactive steps towards infrastructure. The findings pilot a framework for comparative assessment of recognizable standards in transport services, best ethics of management and a necessity of quality infrastructure to guarantee both resilient and sustainable urban mobility.Keywords: transportation demand management, multi-criteria decision support, transport infrastructure, service quality, sustainable transport
Procedia PDF Downloads 2283001 'Antibody Exception' under Dispute and Waning Usage: Potential Influence on Patenting Antibodies
Authors: Xiangjun Kong, Dongning Yao, Yuanjia Hu
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Therapeutic antibodies have become the most valuable and successful class of biopharmaceutical drugs, with a huge market potential and therapeutic advantages. Antibody patents are, accordingly, extremely important. As the technological limitation of the early stage of this field, the U. S. Patent and Trademark Offices (USPTO) have issued guidelines that suggest an exception for patents claiming a genus of antibodies that bind to a novel antigen, even in the absence of any experimental antibody production. This 'antibody exception' allowed for a broad scope on antibody claims, and led a global trend to patent antibodies without antibodies. Disputes around the pertinent patentability and written description issues remain particularly intense. Yet the validity of such patents had not been overtly challenged until Centocor v. Abbott, which restricted the broad scope of antibody patents and hit the brakes on the 'antibody exception'. The courts tend to uphold the requirement for adequate description of antibodies in the patent specifications, to avoid overreaching antibody claims. Patents following the 'antibody exception' are at risk of being found invalid for inadequately describing what they have claimed. However, the relation between the court and USPTO guidelines remains obscure, and the waning of the 'antibody exception' has led to further disputes around antibody patents. This uncertainty clearly affects patent applications, antibody innovations, and even relevant business performance. This study will give an overview of the emergence, debate, and waning usage of the 'antibody exception' in a number of enlightening cases, attempting to understand the specific concerns and the potential influence of antibody patents. We will then provide some possible strategies for antibody patenting, under the current considerations on the 'antibody exception'.Keywords: antibody exception, antibody patent, USPTO (U. S. Patent and Trademark Offices) guidelines, written description requirement
Procedia PDF Downloads 1613000 Revitalization of Sign Language through Deaf Theatre: A Linguistic Analysis of an Art Form Which Combines Physical Theatre, Poetry, and Sign Language
Authors: Gal Belsitzman, Rose Stamp, Atay Citron, Wendy Sandler
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Sign languages are considered endangered. The vitality of sign languages is compromised by its unique sociolinguistic situation, in which hearing parents that give birth to deaf children usually decide to cochlear implant their child. Therefore, these children don’t acquire their natural language – Sign Language. Despite this, many sign languages, such as Israeli Sign Language (ISL) are thriving. The continued survival of similar languages under threat has been associated with the remarkable resilience of the language community. In particular, deaf literary traditions are central in reminding the community of the importance of the language. One example of a deaf literary tradition which has received increased popularity in recent years is deaf theatre. The Ebisu Sign Language Theatre Laboratory, developed as part of the multidisciplinary Grammar of the Body Research Project, is the first deaf theatre company in Israel. Ebisu Theatre combines physical theatre and sign language research, to allow for a natural laboratory to analyze the creative use of the body. In this presentation, we focus on the recent theatre production called ‘Their language’ which tells of the struggle faced by the deaf community to use their own natural language in the education system. A thorough analysis unravels how linguistic properties are integrated with the use of poetic devices and physical theatre techniques in this performance, enabling wider access by both deaf and hearing audiences, without interpretation. Interviews with the audience illustrate the significance of this art form which serves a dual purpose, both as empowering for the deaf community and educational for the hearing and deaf audiences, by raising awareness of community-related issues.Keywords: deaf theatre, empowerment, language revitalization, sign language
Procedia PDF Downloads 1712999 Perceptual Image Coding by Exploiting Internal Generative Mechanism
Authors: Kuo-Cheng Liu
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In the perceptual image coding, the objective is to shape the coding distortion such that the amplitude of distortion does not exceed the error visibility threshold, or to remove perceptually redundant signals from the image. While most researches focus on color image coding, the perceptual-based quantizer developed for luminance signals are always directly applied to chrominance signals such that the color image compression methods are inefficient. In this paper, the internal generative mechanism is integrated into the design of a color image compression method. The internal generative mechanism working model based on the structure-based spatial masking is used to assess the subjective distortion visibility thresholds that are visually consistent to human eyes better. The estimation method of structure-based distortion visibility thresholds for color components is further presented in a locally adaptive way to design quantization process in the wavelet color image compression scheme. Since the lowest subband coefficient matrix of images in the wavelet domain preserves the local property of images in the spatial domain, the error visibility threshold inherent in each coefficient of the lowest subband for each color component is estimated by using the proposed spatial error visibility threshold assessment. The threshold inherent in each coefficient of other subbands for each color component is then estimated in a local adaptive fashion based on the distortion energy allocation. By considering that the error visibility thresholds are estimated using predicting and reconstructed signals of the color image, the coding scheme incorporated with locally adaptive perceptual color quantizer does not require side information. Experimental results show that the entropies of three color components obtained by using proposed IGM-based color image compression scheme are lower than that obtained by using the existing color image compression method at perceptually lossless visual quality.Keywords: internal generative mechanism, structure-based spatial masking, visibility threshold, wavelet domain
Procedia PDF Downloads 2522998 Relationship between Strategic Management and Organizational Culture in Sport Organization (Case Study: Selected Sport Federations of Islamic Republic of Iran)
Authors: Mohammad Ali Ghareh, Habib Honari, Alireza Ahmadi
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The aim of this study was to investigate the relationship between strategic management and organizational culture in sport federations of Islamic Republic of Iran. Strategic management is a set of decisions and actions which define the long term performance of an organization. Organizational culture can be considered as an identity for every organization and somehow gives an identification to organization members. Organizational culture result in a certain commitments in organization members which is more valuable than individual profits and interests. The method of research was descriptive and correlational, conducted as a field study. The statistical population consisted of the employees of 10 sports federations and 170 persons were selected as sample. For data gathering, Barringer and Bluedorn’s strategic management questionnaire (1999) and Sakyn’s organizational culture questionnaire (2001) were used. The reliability of the questionnaires were 0.82 and 0.80 respectively, and the validity was approved by 8 experienced professors in sport management. To analyze data, KS (Kolmogorov–Smirnov) test and Pearson's coefficient were used. The results have shown that there is a significant meaningful relationship between strategic management and organizational culture (p < 0.05, r= 0.62). Beside this, there is a positive relationship between strategic management variables including scanning intensity, planning flexibility, locus of planning, planning horizon, strategic controls, and organizational culture (p < 0.05). Based on this research result it can be derived that strategic management planning and operation in terms of appropriate organizational culture is more applicable. By agreeing on their values and beliefs, adaptation to changes, caring about the individualities, coordination in tasks, modifying the individual and organizational goals, the federations will be able to achieve their strategic goals.Keywords: strategic management, organizational culture, sports federations, Islamic Republic of Iran
Procedia PDF Downloads 3782997 Synthesis of Magnetic Plastic Waste-Reduced Graphene Oxide Composite and Its Application in Dye Adsorption from Aqueous Solution
Authors: Pamphile Ndagijimana, Xuejiao Liu, Zhiwei Li, Yin Wang
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The valorization of plastic wastes, as a mitigation strategy, is attracting the researchers’ attention since these wastes have raised serious environmental concerns. Plastic wastes have been reported to adsorb the organic pollutants in the water environment and to be the main vector of those pollutants in the aquatic environment, especially dyes, as a serious water pollution concern. Recycling technologies of plastic wastes such as landfills, incineration, and energy recovery have been adopted to manage those wastes before getting exposed to the environment. However, they are far from being widely accepted due to their related environmental pollution, lack of space for the landfill as well as high cost. Therefore, modification is necessary for green plastic adsorbent in water applications. Current routes for plastic modification into adsorbents are based on the combustion method, but they have weaknesses of air pollution as well as high cost. Thus, the green strategy for plastic modification into adsorbents is highly required. Furthermore, recent researchers recommended that if plastic wastes are combined with other solid carbon materials, they could promote their application in water treatment. Herein, we present new insight into using plastic waste-based materials as future green adsorbents. Magnetic plastic-reduced graphene oxide (MPrGO) composite was synthesized by cross-linking method and applied in removing methylene blue (MB) from an aqueous solution. Furthermore, the following advantages have been achieved: (i) The density of plastic and reduced graphene oxide were enhanced, (ii) no second pollution of black color in solution, (iii) small amount of graphene oxide (1%) was linked on 10g of plastic waste, and the composite presented the high removal efficiency, (iv) easy recovery of adsorbent from water. The low concentration of MB (10-30mg/L) was all removed by 0.3g of MPrGO. Different characterization techniques such as XRD, SEM, FTIR, BET, XPS, and Raman spectroscopy were performed, and the results confirmed a conjugation between plastic waste and graphene oxide. This MPrGO composite presented a good prospect for the valorization of plastic waste, and it is a promising composite material in water treatment.Keywords: plastic waste, graphene oxide, dye, adsorption
Procedia PDF Downloads 942996 Setting Uncertainty Conditions Using Singular Values for Repetitive Control in State Feedback
Authors: Muhammad A. Alsubaie, Mubarak K. H. Alhajri, Tarek S. Altowaim
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A repetitive controller designed to accommodate periodic disturbances via state feedback is discussed. Periodic disturbances can be represented by a time delay model in a positive feedback loop acting on system output. A direct use of the small gain theorem solves the periodic disturbances problem via 1) isolating the delay model, 2) finding the overall system representation around the delay model and 3) designing a feedback controller that assures overall system stability and tracking error convergence. This paper addresses uncertainty conditions for the repetitive controller designed in state feedback in either past error feedforward or current error feedback using singular values. The uncertainty investigation is based on the overall system found and the stability condition associated with it; depending on the scheme used, to set an upper/lower limit weighting parameter. This creates a region that should not be exceeded in selecting the weighting parameter which in turns assures performance improvement against system uncertainty. Repetitive control problem can be described in lifted form. This allows the usage of singular values principle in setting the range for the weighting parameter selection. The Simulation results obtained show a tracking error convergence against dynamic system perturbation if the weighting parameter chosen is within the range obtained. Simulation results also show the advantage of weighting parameter usage compared to the case where it is omitted.Keywords: model mismatch, repetitive control, singular values, state feedback
Procedia PDF Downloads 1582995 Cryptocurrency as a Payment Method in the Tourism Industry: A Comparison of Volatility, Correlation and Portfolio Performance
Authors: Shu-Han Hsu, Jiho Yoon, Chwen Sheu
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With the rapidly growing of blockchain technology and cryptocurrency, various industries which include tourism has added in cryptocurrency as the payment method of their transaction. More and more tourism companies accept payments in digital currency for flights, hotel reservations, transportation, and more. For travellers and tourists, using cryptocurrency as a payment method has become a way to circumvent costs and prevent risks. Understanding volatility dynamics and interdependencies between standard currency and cryptocurrency is important for appropriate financial risk management to assist policy-makers and investors in marking more informed decisions. The purpose of this paper has been to understand and explain the risk spillover effects between six major cryptocurrencies and the top ten most traded standard currencies. Using data for the daily closing price of cryptocurrencies and currency exchange rates from 7 August 2015 to 10 December 2019, with 1,133 observations. The diagonal BEKK model was used to analyze the co-volatility spillover effects between cryptocurrency returns and exchange rate returns, which are measures of how the shocks to returns in different assets affect each other’s subsequent volatility. The empirical results show there are co-volatility spillover effects between the cryptocurrency returns and GBP/USD, CNY/USD and MXN/USD exchange rate returns. Therefore, currencies (British Pound, Chinese Yuan and Mexican Peso) and cryptocurrencies (Bitcoin, Ethereum, Ripple, Tether, Litecoin and Stellar) are suitable for constructing a financial portfolio from an optimal risk management perspective and also for dynamic hedging purposes.Keywords: blockchain, co-volatility effects, cryptocurrencies, diagonal BEKK model, exchange rates, risk spillovers
Procedia PDF Downloads 1482994 Investor Psychology, Housing Prices, and Stock Market Response to Policy Decisions During the Covid-19 Recession in the United States
Authors: Ly Nguyen, Vidit Munshi
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During the Covid-19 recession, the United States government has implemented several instruments to mitigate the impacts and revitalize the economy. This paper explores the effects of the various government policy decisions on stock returns, housing prices, and investor psychology during the pandemic in the United States. A numerous previous literature studies on this subject, yet very few focus on the context similar to what we are currently experiencing. Our monthly data covering the period from January 2019 through July 2021 were collected from Datastream. Utilizing the VAR model, we document a dynamic relationship between the market and policy actions throughout the period. In particular, the movements of Unemployment, Stock returns, and Housing prices are strongly sensitive to changes in government policies. Our results also indicate that changes in production level, stock returns, and interest rates decisions influence how investors perceived future market risk and expectations. We do not find any significant nexus between monetary and fiscal policy. Our findings imply that information on government policy and stock market performance provide useful feedback to one another in order to make better decisions in the current and future pandemic. Understanding how the market responds to a shift in government practices has important implications for authorities in implementing policy to avoid assets bubbles and market overreactions. The paper also provides useful implications for investors in evaluating the effectiveness of different policies and diversifying portfolios to minimize systematic risk and maximize returns.Keywords: Covid-19 recession, United States, government policies, investor psychology, housing prices, stock market returns
Procedia PDF Downloads 1772993 The Effect of Female Access to Healthcare and Educational Attainment on Nigerian Agricultural Productivity Level
Authors: Esther M. Folarin, Evans Osabuohien, Ademola Onabote
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Agriculture constitutes an important part of development and poverty mitigation in lower-middle-income countries, like Nigeria. The level of agricultural productivity in the Nigerian economy in line with the level of demand necessary to meet the desired expectation of the Nigerian populace is threatening to meeting the standard of the United Nations (UN) Sustainable Development Goals (SDGs); This includes the SDG-2 (achieve food security through agricultural productivity). The overall objective of the study is to reveal the performance of the interaction variable in the model among other factors that help in the achievement of greater Nigerian agricultural productivity. The study makes use of Wave 4 (2018/2019) of the Living Standard Measurement Studies, Integrated Survey on Agriculture (LSMS-ISA). Qualitative analysis of the information was also used to provide complimentary answers to the quantitative analysis done in the study. The study employed human capital theory and Grossman’s theory of health Demand in explaining the relationships that exist between the variables within the model of the study. The study engages the Instrumental Variable Regression technique in achieving the broad objectives among other techniques for the other specific objectives. The estimation results show that there exists a positive relationship between female healthcare and the level of female agricultural productivity in Nigeria. In conclusion, the study emphasises the need for more provision and empowerment for greater female access to healthcare and educational attainment levels that aids higher female agricultural productivity and consequently an improvement in the total agricultural productivity of the Nigerian economy.Keywords: agricultural productivity, education, female, healthcare, investment
Procedia PDF Downloads 872992 Design Study on a Contactless Material Feeding Device for Electro Conductive Workpieces
Authors: Oliver Commichau, Richard Krimm, Bernd-Arno Behrens
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A growing demand on the production rate of modern presses leads to higher stroke rates. Commonly used material feeding devices for presses like grippers and roll-feeding systems can only achieve high stroke rates along with high gripper forces, to avoid stick-slip. These forces are limited by the sensibility of the surfaces of the workpieces. Stick-slip leads to scratches on the surface and false positioning of the workpiece. In this paper, a new contactless feeding device is presented, which develops higher feeding force without damaging the surface of the workpiece through gripping forces. It is based on the principle of the linear induction motor. A primary part creates a magnetic field and induces eddy currents in the electrically conductive material. A Lorentz-Force applies to the workpiece in feeding direction as a mutual reaction between the eddy-currents and the magnetic induction. In this study, the FEA model of this approach is shown. The calculation of this model was used to identify the influence of various design parameters on the performance of the feeder and thus showing the promising capabilities and limits of this technology. In order to validate the study, a prototype of the feeding device has been built. An experimental setup was used to measure pulling forces and placement accuracy of the experimental feeder in order to give an outlook of a potential industrial application of this approach.Keywords: conductive material, contactless feeding, linear induction, Lorentz-Force
Procedia PDF Downloads 1832991 An Improved Total Variation Regularization Method for Denoising Magnetocardiography
Authors: Yanping Liao, Congcong He, Ruigang Zhao
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The application of magnetocardiography signals to detect cardiac electrical function is a new technology developed in recent years. The magnetocardiography signal is detected with Superconducting Quantum Interference Devices (SQUID) and has considerable advantages over electrocardiography (ECG). It is difficult to extract Magnetocardiography (MCG) signal which is buried in the noise, which is a critical issue to be resolved in cardiac monitoring system and MCG applications. In order to remove the severe background noise, the Total Variation (TV) regularization method is proposed to denoise MCG signal. The approach transforms the denoising problem into a minimization optimization problem and the Majorization-minimization algorithm is applied to iteratively solve the minimization problem. However, traditional TV regularization method tends to cause step effect and lacks constraint adaptability. In this paper, an improved TV regularization method for denoising MCG signal is proposed to improve the denoising precision. The improvement of this method is mainly divided into three parts. First, high-order TV is applied to reduce the step effect, and the corresponding second derivative matrix is used to substitute the first order. Then, the positions of the non-zero elements in the second order derivative matrix are determined based on the peak positions that are detected by the detection window. Finally, adaptive constraint parameters are defined to eliminate noises and preserve signal peak characteristics. Theoretical analysis and experimental results show that this algorithm can effectively improve the output signal-to-noise ratio and has superior performance.Keywords: constraint parameters, derivative matrix, magnetocardiography, regular term, total variation
Procedia PDF Downloads 1572990 Positive effect of Cu2+ and Ca2+ on the Thermostability of Bambara Groundnut Peroxidase A6, and its Catalytic Efficiency Toward the Oxidation of 3,3,5,5 -Tetramethyl Benzidine
Authors: Yves Mann Elate Lea Mbassi, Marie Solange Evehe Bebandoue, Wilfred Fon Mbacham
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Improving the catalytic performance of enzymes has been a long-standing theme of analytical biochemistry research. Induction of peroxidase activity by metals is a common reaction in higher plants. We thought that this increase in peroxidase activity may be due, on the one hand, to the stimulation of the gene expression of these enzymes but also to a modification of their chemical reactivity following the binding of some metal ions on their active site. We tested the effect of some metal salts (MgCl₂, MnCl₂, ZnCl₂, CaCl₂ and CuSO₄) on the activity and thermostability of peroxidase A6, a thermostable peroxidase that we discovered and purified in a previous study. The chromogenic substrate used was 3,3′,5,5′-tetramethylbenzidine. Of all the metals tested for their effect on A6, only magnesium and copper had a significant effect on the activity of the enzyme at room temperature. The Mann-Whitney test shows a slight inhibitory effect of activity by the magnesium salt (P = 0.043), while the activity of the enzyme is 5 times higher in the presence of the copper salt (P = 0.002). Moreover, the thermostability of peroxidase A6 is increased when calcium and copper salts are present. The activity in the presence of CaCl₂ is 8 times higher than the residual activity of the enzyme alone after incubation at 80°C for 10 min and 35 times higher in the presence of CuSO4 under the same conditions. In addition, manganese and zinc salts slightly reduce the thermostability of the enzyme. The activity and structural stability of peroxidase A6 can clearly be activated by Cu₂+, which therefore enhance the oxidation of 3,3′,5,5′-tetramethylbenzidine, which was used in this study as a chromogenic substrate. Ca₂+ likely has a more stabilizing function for the catalytic site.Keywords: peroxidase activity, copper ions, calcium ions, thermostability
Procedia PDF Downloads 79