Search results for: increasing bearing capacity
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11797

Search results for: increasing bearing capacity

8947 Wheel Diameter and Width Influence in Variability of Brake Data Measurement at Ministry of Transport Facilities

Authors: Carolina Senabre, Sergio Valero, Emilio Velasco

Abstract:

The brake systems of vehicles are tested periodically by a “brake tester” at Ministry of Transport (MOT) stations. This tester measures the effectiveness of vehicle. This parameter is established by the International Committee of Vehicle Inspection (CITA). In this paper, we present an investigation of the influence of the tire size on the measurements of brake force on three MOT brake testers. We performed an analysis of the vehicle braking capacity test at MOT stations. The influence of varying wheel diameter and width on the measurement of braking at MOT stations has been analyzed. Thereby, the MOT brake tester as a verification system for a vehicle has been evaluated.

Keywords: brake tester, ministry of transport facilities, wheel diameter, efficiency

Procedia PDF Downloads 377
8946 Impact of Soot on NH3-SCR, NH3 Oxidation and NH3 TPD over Cu/SSZ-13 Zeolite

Authors: Lidija Trandafilovic, Kirsten Leistner, Marie Stenfeldt, Louise Olsson

Abstract:

Ammonia Selective Catalytic Reduction (NH3 SCR), is one of the most efficient post combustion abatement technologies for removing NOx from diesel engines. In order to remove soot, diesel particulate filters (DPF) are used. Recently, SCR coated filters have been introduced, which captures soot and simultaneously is active for ammonia SCR. There are large advantages with using SCR coated filters, such as decreased volume and also better light off characteristics, since both the SCR function as well as filter function is close to the engine. The objective of this work was to examine the effect of soot, produced using an engine bench, on Cu/SSZ-13 catalysts. The impact of soot on Cu/SSZ-13 in standard SCR, NH3 oxidation, NH3 temperature programmed desorption (TPD), as well as soot oxidation (with and without water) was examined using flow reactor measurements. In all experiments, prior to the soot loading, the fresh activity of Cu/SSZ-13 was recorded with stepwise increasing the temperature from 100°C till 600°C. Thereafter, the sample was loaded with soot and the experiment was repeated in the temperature range from 100°C till 700°C. The amount of CO and CO2 produced in each experiment is used to calculate the soot oxidized at each steady state temperature. The soot oxidized during the heating to next temperature step is included, e.g. the CO+CO2 produced when increasing the temperature to 600°C is added to the 600°C step. The influence of the two factors seem to be of the most importance to soot oxidation: ammonia and water. The influence of water on soot oxidation shift the maximum of CO2 and CO production towards lower temperatures, thus water increases the soot oxidation. Moreover, when adding ammonia to the system it is clear that the soot oxidation is lowered in the presence of ammonia, resulting in larger integrated COx at 500°C for O2+H2O, while opposite results at 600 °C was received where more was oxidised for O2+H2O+NH3 case. To conclude the presence of ammonia reduces the soot oxidation, which is in line with the ammonia TPD results where we found ammonia storage on the soot. Interestingly, during ammonia SCR conditions the activity for soot oxidation is regained at 500°C. At this high temperature the SCR zone is very short, thus the majority of the catalyst is not exposed to ammonia and therefore the inhibition effect of ammonia is not observed.

Keywords: NH3-SCR, Cu/SSZ-13, soot, zeolite

Procedia PDF Downloads 237
8945 Seroprevalence and Determinants of Toxoplasmosis in Pregnant Women Attending Antenatal Clinic at the University Teaching Hospital, Lusaka, Zambia: A Cross-Sectional Study

Authors: Christiana Frimpong, Mpundu Makasa, Lungowe Sitali, Charles Michelo

Abstract:

Background: Toxoplasmosis is a neglected zoonotic disease which is prevalent among pregnant women especially in Africa. This study aimed to determine the seroprevalence and determinants of the disease among pregnant women attending the antenatal clinic at the University Teaching Hospital (UTH). Method: A cross-sectional study was employed where 411 pregnant women attending the antenatal clinic at UTH were interviewed using closed-ended questionnaires. Their blood was also tested for Toxoplasma gondii IgG and IgM antibodies using the OnSite Toxo IgG/IgM Combo Rapid Test cassettes by CTK Biotech, Inc, USA. Result: The overall seroprevalence of the infection (IgG) was 5.87%. There was no seropositive IgM result. Contact with cats showed 7.81 times the risk of contracting the infection in the pregnant women and being a farmer/being involved in construction work showed 15.5 times likelihood of contracting the infection. Socio-economic status of the pregnant women also presented an inverse relationship (showed association) with the infection graphically. However, though there were indications of the association between contact with cats, employment type as well as the socioeconomic status of the pregnant women with the infection, there was not enough evidence to suggest these factors as significant determining factors of Toxoplasma gondii infection in our study population. Conclusion: There is a low prevalence of Toxoplasma gondii infection among pregnant women in Lusaka, Zambia. Screening for the infection among pregnant women can be done once or twice during pregnancy to help protect both mother and child from the disease. Health promotion among women of child bearing age on the subject is of immense importance in order to help curb the situation. Further studies especially that of case-control and cohort studies should be carried out in the country in order to better ascertain the extent of the condition nationwide.

Keywords: determinants, pregnant women, seroprevalence, toxoplasmosis, University Teaching Hospital (UTH), Zambia

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8944 A Time and Frequency Dependent Study of Low Intensity Microwave Radiation Induced Endoplasmic Reticulum Stress and Alteration of Autophagy in Rat Brain

Authors: Ranjeet Kumar, Pravin Suryakantrao Deshmukh, Sonal Sharma, Basudev Banerjee

Abstract:

With the tremendous increase in exposure to radiofrequency microwaves emitted by mobile phones, globally public awareness has grown with regard to the potential health hazards of microwaves on the nervous system in the brain. India alone has more than one billion mobile users out of 4.3 billion globally. Our studies have suggested that radio frequency able to affect neuronal alterations in the brain, and hence, affecting cognitive behaviour. However, adverse effect of low-intensity microwave exposure with endoplasmic reticulum stress and autophagy has not been evaluated yet. In this study, we explore whether low-intensity microwave induces endoplasmic reticulum stress and autophagy with varying frequency and time duration in Wistar rat. Ninety-six male Wistar rat were divided into 12 groups of 8 rats each. We studied at 900 MHz, 1800 MHz, and 2450 MHz frequency with reference to sham-exposed group. At the end of the exposure, the rats were sacrificed to collect brain tissue and expression of CHOP, ATF-4, XBP-1, Bcl-2, Bax, LC3 and Atg-4 gene was analysed by real-time PCR. Significant fold change (p < 0.05) of gene expression was found in all groups of 1800 MHz and 2450 MHz exposure group in comparison to sham exposure group. In conclusion, the microwave exposure able to induce ER stress and modulate autophagy. ER (endoplasmic reticulum) stress and autophagy vary with increasing frequency as well as the duration of exposure. Our results suggested that microwave exposure is harmful to neuronal health as it induces ER stress and hampers autophagy in neuron cells and thereby increasing the neuron degeneration which impairs cognitive behaviour of experimental animals.

Keywords: autophagy, ER stress, microwave, nervous system, rat

Procedia PDF Downloads 133
8943 Selection of Endophytcs Fungi Isolated from Date Palm, Halotolerants and Productors of Secondary Metabolite

Authors: Fadila Mohamed Mahmoud., Derkaoui I., Krimi Z.

Abstract:

Date palm is a plant which presents a very good adaptation to the difficult conditions of the environment in particular to the drought and saline stress even at high temperatures. This adaptation is related on the biology of the plant and to the presence of a microflora endophyte which live inside its tissues. Fifteen endophytics fungi isolated from date palm were tested in vitro in the presence of various NaCl concentrations to select halotolerantes isolates. These same endophytes were tested for their colonizing capacity by the description of the production of secondary metabolites more particularly the enzymes (pectinases, proteases, and phosphorylases), and the production of antibiotics and growth hormones. Significant difference was observed between the isolates with respect to the tests carried out.

Keywords: Date palm, Halotolerantes, endophyte, Secondary metabolites.

Procedia PDF Downloads 521
8942 Analysis of Supply Chain Risk Management Strategies: Case Study of Supply Chain Disruptions

Authors: Marcelo Dias Carvalho, Leticia Ishikawa

Abstract:

Supply Chain Risk Management refers to a set of strategies used by companies to avoid supply chain disruption caused by damage at production facilities, natural disasters, capacity issues, inventory problems, incorrect forecasts, and delays. Many companies use the techniques of the Toyota Production System, which in a way goes against a better management of supply chain risks. This paper studies key events in some multinationals to analyze the trade-off between the best supply chain risk management techniques and management policies designed to create lean enterprises. The result of a good balance of these actions is the reduction of losses, increased customer trust in the company and better preparedness to face the general risks of a supply chain.

Keywords: just in time, lean manufacturing, supply chain disruptions, supply chain management

Procedia PDF Downloads 338
8941 The Structural, Elastic, Thermal, Electronic, and Magnetic Properties of Intermetallic rmn₂ge₂ (R=CA, Y, ND)

Authors: I. Benkaddour, Y. Benkaddour, A. Benk Addour

Abstract:

The structural, elastic, Thermal, electronic, and magnetic properties of intermetallic RMn₂Ge₂ (R= Ca, Y, Nd) are investigated by density functional theory (DFT), using the full potential –linearised augmented plane wave method (FP-LAPW). In this approach, the local-density approximation (LDA) is used for the exchange-correlation (XC) potential. The equilibrium lattice constant and magnetic moment agree well with the experiment. The density of states shows that these phases are conductors, with contribution predominantly from the R and Mn d states. We have determined the elastic constants C₁₁, C₁₂, C₁₃, C₄₄, C₃₃, andC₆₆ at ambient conditions in, which have not been established neither experimentally nor theoretically. Thermal properties, including the relative expansion coefficients and the heat capacity, have been estimated using a quasi-harmonic Debye model.

Keywords: RMn₂Ge₂, intermetallic, first-principles, density of states, mechanical properties

Procedia PDF Downloads 91
8940 Munting Kamay, Munting Gawa: Children's Development Training, a UCU Experience

Authors: Elizabeth A. Montero

Abstract:

The project contemplated in this study particularly aimed at enabling public school children of ages ten to twelve who belong to low and middle income families. The pupils were provided training on communication, work, computer and social skills. In this study, the researcher hypothesized that children given the opportunity to develop a skill through guidance and proper supervision will significantly learn, improve and develop a skill. Since children’s minds are highly absorbent like a sponge absorbing anything within its capacity to take, it is ideal and necessary that education should provide an environment that is rich offering an array of meaningful experiences. The context of this study is well balanced since it catered to the children’s communication, work, computer and social skills.

Keywords: Munting Kamay, Munting Gawa, children’s development training, UCU experience

Procedia PDF Downloads 439
8939 Treatment of Low-Grade Iron Ore Using Two Stage Wet High-Intensity Magnetic Separation Technique

Authors: Moses C. Siame, Kazutoshi Haga, Atsushi Shibayama

Abstract:

This study investigates the removal of silica, alumina and phosphorus as impurities from Sanje iron ore using wet high-intensity magnetic separation (WHIMS). Sanje iron ore contains low-grade hematite ore found in Nampundwe area of Zambia from which iron is to be used as the feed in the steelmaking process. The chemical composition analysis using X-ray Florence spectrometer showed that Sanje low-grade ore contains 48.90 mass% of hematite (Fe2O3) with 34.18 mass% as an iron grade. The ore also contains silica (SiO2) and alumina (Al2O3) of 31.10 mass% and 7.65 mass% respectively. The mineralogical analysis using X-ray diffraction spectrometer showed hematite and silica as the major mineral components of the ore while magnetite and alumina exist as minor mineral components. Mineral particle distribution analysis was done using scanning electron microscope with an X-ray energy dispersion spectrometry (SEM-EDS) and images showed that the average mineral size distribution of alumina-silicate gangue particles is in order of 100 μm and exists as iron-bearing interlocked particles. Magnetic separation was done using series L model 4 Magnetic Separator. The effect of various magnetic separation parameters such as magnetic flux density, particle size, and pulp density of the feed was studied during magnetic separation experiments. The ore with average particle size of 25 µm and pulp density of 2.5% was concentrated using pulp flow of 7 L/min. The results showed that 10 T was optimal magnetic flux density which enhanced the recovery of 93.08% of iron with 53.22 mass% grade. The gangue mineral particles containing 12 mass% silica and 3.94 mass% alumna remained in the concentrate, therefore the concentrate was further treated in the second stage WHIMS using the same parameters from the first stage. The second stage process recovered 83.41% of iron with 67.07 mass% grade. Silica was reduced to 2.14 mass% and alumina to 1.30 mass%. Accordingly, phosphorus was also reduced to 0.02 mass%. Therefore, the two stage magnetic separation process was established using these results.

Keywords: Sanje iron ore, magnetic separation, silica, alumina, recovery

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8938 A Scoping Review of Psychosocial Interventions for the Survivors and/or Victims of Intimate Partner Violence in Low- and Middle-Income Countries

Authors: Mukondi Nethavhakone

Abstract:

The high prevalence of violence against women is a global public health problem. Our societies have become dangerous places for women. Women during their child-bearing ages are at a higher risk of experiencing emotional, physical, and sexual violence. What makes it more concerning is that these violent acts are perpetrated by family members or partners, or ex-partners. Intimate Partner Violence (IPV) is associated with long-lasting physical, reproductive, sexual, mental, and maternal health implications. Expectedly women’s mental health would dimmish as a result of experiencing IPV. The burden of violence against women is seen to be heavier in low- and middle-income countries (LMICs) compared to the rest of the world. Countries have committed to eliminating all forms of violence against women through the sustainable development goal, aiming to see changes by the year 2030. As such, various countries have implemented psychosocial interventions of different levels of impact. However, little is known, especially in low- and middle-income countries, with regard to the potential of psychosocial interventions for IPV to improve the mental health outcomes for the survivors and/or victims of IPV. Analysing the risk for IPV through a social-ecological theoretical approach, low- and middle-income countries still readdressing gender inequality which is the cause of intimate partner violence. That is why it is taking time for these countries to shift psychosocial interventions to focus more on the improvement of the mental health of the survivors. It is, therefore, against this backdrop that the researcher intends to undertake a scoping review to understand the nature and characteristics of psychosocial interventions that have been implemented in low- and middle-income countries. With the findings from the scoping review, the researcher aims to develop a conceptual framework that may be a useful resource for healthcare practitioners and researchers in low- and middle-income countries. As this area of research has not been thoroughly reviewed, the results from this scoping will determine whether a systematic review will be justifiable. Additionally, the researcher will identify gaps and opportunities for future research in this area.

Keywords: mental health improvement, psychosocial interventions, intimate partner violence, LMICs

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8937 Effects of Reversible Watermarking on Iris Recognition Performance

Authors: Andrew Lock, Alastair Allen

Abstract:

Fragile watermarking has been proposed as a means of adding additional security or functionality to biometric systems, particularly for authentication and tamper detection. In this paper we describe an experimental study on the effect of watermarking iris images with a particular class of fragile algorithm, reversible algorithms, and the ability to correctly perform iris recognition. We investigate two scenarios, matching watermarked images to unmodified images, and matching watermarked images to watermarked images. We show that different watermarking schemes give very different results for a given capacity, highlighting the importance of investigation. At high embedding rates most algorithms cause significant reduction in recognition performance. However, in many cases, for low embedding rates, recognition accuracy is improved by the watermarking process.

Keywords: biometrics, iris recognition, reversible watermarking, vision engineering

Procedia PDF Downloads 459
8936 Effect of Flow Holes on Heat Release Performance of Extruded-Type Heat Sink

Authors: Jung Hyun Kim, Gyo Woo Lee

Abstract:

In this study, the enhancement of the heat release performance of an extruded-type heat sink to prepare the large-capacity solar inverter thru the flow holes in the base plate near the heat sources was investigated. Optimal location and number of the holes in the baseplate were determined by using a commercial computation program. The heat release performance of the shape-modified heat sink was measured experimentally and compared with that of the simulation. The heat sink with 12 flow holes in the 18-mm-thick base plate has a 8.1% wider heat transfer area, a 2.5% more mass flow of air, and a 2.7% higher heat release rate than those of the original heat sink. Also, the surface temperature of the base plate was lowered 1.5°C by the holes.

Keywords: heat sink, forced convection, heat transfer, performance evaluation, flow holes

Procedia PDF Downloads 536
8935 Offenders and Victims in Public Focus: Media Coverage about Crime and Its Consequences

Authors: Melanie Verhovnik

Abstract:

Media shape the image of crime, peoples’ believes, attitudes and sometimes also behaviors. Media not only gives the impression that crime is increasing, it also suggest that very violent crime is more common than it actually is. It is also no wonder that humans are more afraid of being involved in a crime committed by strangers than committed by somebody they know – because this is the media construct. With the help of three case studies, the paper analyzes how media frames crime and criminals and gives valuable hints as to what better reporting could look like.

Keywords: court reporting, offenders in media, quantitative content analysis, victims in media

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8934 Lifestyle Behaviors among Jordanian Obese Children Aged 6-9 Years: A Cross-Sectional Study

Authors: Ayman Bani Salameh

Abstract:

Background: Obesity in children is in increasing in developed and developing countries, which leads to morbidity and premature mortality. Lifestyle behaviors are an important issue in minimizing this problem and subsequent complications. Thus, this study purposed to assess lifestyle behaviors, including dietary habits and physical activity, among Jordanian obese children aged 6-9 years. Methods: A cross-sectional study was conducted on 324 children aged 6-9 years using a questionnaire consisting of items measuring dietary habits (7 items) and physical activity (8 items). Results: Findings showed that obese children had bad dietary habits involved in the number of meals eaten day (M= 5.06, SD=1.14), number of snacks of sweet/ chocolates daily (M= 3. 61, SD=0.82), and number of glasses of sweet fizzy drinks/day (M= 3.39, SD=0.96). Moreover, they had poor physical activity represented in the number of playing or training in an activity like dancing, swimming, and walking in the past week (M= 0.06, SD=1.01), number of days in participating in moderate physical activity last week (M= 0.06, SD=1.01), time spending in using a computer, watching TV, watching videos or using the internet as a part of study or homework in the last week (M= 16.88, SD=2.37), and ), time spending in using a computer, watching TV, watching videos or using the internet for fun or recreation in the past week (M= 14.44, SD=2.37). Conclusion: Obese children aged 6-9 had unhealthy lifestyle behaviors, which could expose them to a high risk of increasing comorbidities associated with obesity. Therefore, this preliminary study helps develop an intervention program based on modifying unhealthy behaviors, including bad dietary habits and a sedentary lifestyle. The results provide baseline data about the strategies for developing intervention programs for weight reduction.

Keywords: obesity, children, behaviors, lifestyle

Procedia PDF Downloads 87
8933 Relieving Flood Damages In Malaysia through Tax Policies And Measures: A Comparative Analysis

Authors: Chee Fei Chang, May Yee Ng

Abstract:

As a result of its geographical location, flood is a natural disaster that happens regularly in Malaysia. Every year, heavy rainfall is brought by the cyclical monsoon to the East coast of Peninsular Malaysia. In recent years, the occurrence of unexpected heavy downpour somehow connected to climate-change phenomena is also on the increasing trend. Ironically, despite that Malaysians have suffered significant monetary losses as a result of the recurring floods in past many decades, little has been done by the government from the perspective of taxation. Perhaps due to political reason or as a populist measure, the federal and local government are more inclined to offer small cash handout then rolling out long-term tax policy or measure in relieving the financial and tax burden of the victims and affected business entities. Except for the one-off tax break granted to affected businesses in 2007, the authors have not found any income tax exemption or deduction order gazetted with regard to flood disaster. Hence, it is imperative for this study to explore the need and challenges of implementing flood inflicted disaster tax relief or credit in Malaysia. This research consists of two major parts. First, the assessment of relevant tax policies/ measures with regard to non-government organisations and other affected parties. Content and thematic analyses will be applied on current tax legislations and orders issued for this part. Second, a comparative analysis will be conducted benchmarking various disaster tax reliefs and credits implemented in developed countries. Resulting from the increasing climate change-related disasters in Malaysia, the findings of this study will shed light on the importance of introducing disaster tax relief measures to assist individual victims as well as the affected businesses.

Keywords: climate-changed related disaster, disaster tax credits, tax relief for victims, tax measures for disaster recovery

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8932 Development of Social Competence in the Preparation and Continuing Training of Adult Educators

Authors: Genute Gedviliene, Vidmantas Tutlys

Abstract:

The aim of this paper is to reveal the deployment and development of the social competence in the higher education programmes of adult education and in the continuing training and competence development of the andragogues. There will be compared how the issues of cooperation and communication in the learning and teaching processes are treated in the study programmes and in the courses of continuing training of andragogues. Theoretical and empirical research methods were combined for research analysis. For the analysis the following methods were applied: 1) Literature and document analysis helped to highlight the communication and cooperation as fundamental phenomena of the social competence, it’s important for the adult education in the context of digitalization and globalization. There were also analyzed the research studies on the development of social competence in the field of andragogy, as well as on the place and weight of the social competence in the overall competence profile of the andragogue. 2) The empirical study is based on questionnaire survey method. The population of survey consists of 240 students of bachelor and master degree studies of andragogy in Lithuania and of 320 representatives of the different bodies and institutions involved in the continuing training and professional development of the adult educators in Lithuania. The themes of survey questionnaire were defined on the basis of findings of the literature review and included the following: 1) opinions of the respondents on the role and place of a social competence in the work of andragogue; 2) opinions of the respondents on the role and place of the development of social competence in the curricula of higher education studies and continuing training courses; 3) judgements on the implications of the higher education studies and courses of continuing training for the development of social competence and it’s deployment in the work of andragogue. Data analysis disclosed a wide range of ways and modalities of the deployment and development of social competence in the preparation and continuing training of the adult educators. Social competence is important for the students and adult education providers not only as the auxiliary capability for the communication and transfer of information, but also as the outcome of collective learning leading to the development of new capabilities applied by the learners in the learning process, their professional field of adult education and their social life. Equally so, social competence is necessary for the effective adult education activities not only as an auxiliary capacity applied in the teaching process, but also as a potential for improvement, development and sustainability of the didactic competence and know-how in this field. The students of the higher education programmes in the field of adult education treat social competence as important generic capacity important for the work of adult educator, whereas adult education providers discern the concrete issues of application of social competence in the different processes of adult education, starting from curriculum design and ending with assessment of learning outcomes.

Keywords: adult education, andragogues, social competence, curriculum

Procedia PDF Downloads 148
8931 Dietary Modification and Its Effects in Overweight or Obese Saudi Women with or without Type 2 Diabetes Mellitus

Authors: Nasiruddin Khan, Nasser M. Al-Daghri, Dara A. Al-Disi, Asim Al-Fadda, Mohamed Al-Seif, Gyanendra Tripathi, A. L. Harte, Philip G. Mcternan

Abstract:

For the last few decades, the prevalence of type 2 diabetes mellitus (T2DM) in the Kingdom of Saudi Arabia (KSA) is increasing alarmingly high and is unprecedented at 31.6 %. Preventive measures should be taken to curb down the increasing incidence. In this prospective, 3-month study, we aimed to determine whether dietary modification program would confer favorable affects among overweight and obese adult Saudi women with or without T2DM. A total of 92 Saudi women [18 healthy controls, 24 overweight subjects and 50 overweight or obese patients with early onset T2DM were included in this prospective study. Baseline anthropometrics and fasting blood samples were taken at baseline and after 3 months. Fasting blood sugar and lipid profile were measured routinely. A 500 Kcal deficit energy diet less than their daily recommended dietary allowances were prescribed to all participants. After 3 months of follow-up visit, significant improvements were observed in both the overweight and DMT2 group as compared to baseline with decreased mean BMI [Overweight Group 28.54±1.49 versus 27.95±2.25, p<0.05; DMT2 group 35.24±7.67 versus 35.04±8.07, p<0.05] and hip circumference [Overweight group 109.67±5.01 versus 108.07±4.07, p<0.05; DMT2 group 112.3±13.43 versus 109.21±12.71, p<0.01]. Moreover, in the overweight group, baseline HDL-cholesterol was significantly associated with protein intake and inversely associated with carbohydrate intake in controls. In the DMT2 group, carbohydrate intake at baseline was significantly associated with BMI. A 3-month 500kcal/day deficit dietary modification alone is probably effective among adult overweight or obese Saudi females without or with T2DM. Longer prospective studies are to determine whether the dietary intervention alone can reduce progression of T2DM among high-risk adult Arabs.

Keywords: diet, lipid, obesity, T2DM

Procedia PDF Downloads 476
8930 Improving Power Quality in Wind Power Generation System

Authors: A. Omeiri, A. Djellad, P. O. Logerais, O. Riou, J. F. Durastanti

Abstract:

With the growing of electrical energy demand, wind power capacity has experienced tremendous growth in the past decade, thanks to wind power’s environmental benefits. Direct driven permanent magnet synchronous generator (PMSG) with a full size back-to-back converter set is one of the promising technologies employed with wind power generation. Wind grid integration brings the problems of voltage fluctuation and harmonic pollution. In the present study, the filter is placed between the wind system and the network to reduce the total harmonic distortion (THD) and enhance power quality during disturbances. The models of wind turbine, PMSG, power electronic converters and the filter are implemented in MATLAB/SIMULINK environment.

Keywords: wind energy conversion system, PMSG, PWM, THD, power quality, passive filter

Procedia PDF Downloads 649
8929 Effect of Polymer Coated Urea on Nutrient Efficiency and Nitrate Leaching Using Maize and Annual Ryegrass

Authors: Amrei Voelkner, Nils Peters, Thomas Mannheim

Abstract:

The worldwide exponential growth of the population and the simultaneous increasing food production requires the strategic realization of sustainable and improved cultivation systems to ensure the fertility of arable land and to guarantee the food supply for the whole world. To fulfill this target, large quantities of fertilizers have to be applied to the field, but the long-term environmental impacts remain uncertain. Thus, a combined system would be necessary to increase the nutrient availability for plants while reducing nutrient losses (e.g. NO3- by leaching) to the environment. To enhance the nutrient efficiency, polymer coated fertilizer with a controlled release behavior have been developed. This kind of fertilizer ensures a delayed release of nutrients to synchronize the nutrient supply with the demand of different crops. In the last decades, research focused primarily on semi-permeable polyurethane coatings, which remain in the soil for a long period after the complete solvation of the fertilizer core. Within the implementation of the new European Regulation Directive the replacement of non-degradable synthetic polymers by degradable coatings is necessary. It was, therefore, the objective of this study to develop a total biodegradable polymer (to CO2 and H2O) coating according to ISO 17556 and to compare the retarding effect of the biodegradable coatings with commercially available non-degradable products. To investigate the effect of ten selected coated urea fertilizer on the yield of annual ryegrass and maize, the fresh and dry mass, the percentage of total nitrogen and main nutrients were analyzed in greenhouse experiments in sixfold replications using near-infrared spectroscopy. For the experiments, a homogenized and air-dried loamy sand (Cambic Luvisol) was equipped with a basic fertilization of P, K, Mg and S. To investigate the effect of nitrogen level increase, three levels (80%, 100%, 120%) were established, whereas the impact of CRF granules was determined using a N-level of 100%. Additionally, leaching of NO3- from pots planted with annual ryegrass was examined to evaluate the retention capacity of urea by the polymer coating. For this, leachate from Kick-Brauckmann-Pots was collected daily and analyzed for total nitrogen, NO3- and NH4+ in twofold repetition once a week using near-infrared spectroscopy. We summarize from the results that the coated fertilizer have a clear impact on the yield of annual ryegrass and maize. Compared to the control, an increase of fresh and dry mass could be recognized. Partially, the non-degradable coatings showed a retarding effect for a longer period, which was however reflected by a lower fresh and dry mass. It was ascertained that the percentage of leached-out nitrate could be reduced markedly. As a conclusion, it could be pointed out that the impact of coated fertilizer of all polymer types might contribute to a reduction of negative environmental impacts in addition to their fertilizing effect.

Keywords: biodegradable polymers, coating, enhanced efficiency fertilizers, nitrate leaching

Procedia PDF Downloads 271
8928 Argos System: Improvements and Future of the Constellation

Authors: Sophie Baudel, Aline Duplaa, Jean Muller, Stephan Lauriol, Yann Bernard

Abstract:

Argos is the main satellite telemetry system used by the wildlife research community, since its creation in 1978, for animal tracking and scientific data collection all around the world, to analyze and understand animal migrations and behavior. The marine mammals' biology is one of the major disciplines which had benefited from Argos telemetry, and conversely, marine mammals biologists’ community has contributed a lot to the growth and development of Argos use cases. The Argos constellation with 6 satellites in orbit in 2017 (Argos 2 payload on NOAA 15, NOAA 18, Argos 3 payload on NOAA 19, SARAL, METOP A and METOP B) is being extended in the following years with Argos 3 payload on METOP C (launch in October 2018), and Argos 4 payloads on Oceansat 3 (launch in 2019), CDARS in December 2021 (to be confirmed), METOP SG B1 in December 2022, and METOP-SG-B2 in 2029. Argos 4 will allow more frequency bands (600 kHz for Argos4NG, instead of 110 kHz for Argos 3), new modulation dedicated to animal (sea turtle) tracking allowing very low transmission power transmitters (50 to 100mW), with very low data rates (124 bps), enhancement of high data rates (1200-4800 bps), and downlink performance, at the whole contribution to enhance the system capacity (50,000 active beacons per month instead of 20,000 today). In parallel of this ‘institutional Argos’ constellation, in the context of a miniaturization trend in the spatial industry in order to reduce the costs and multiply the satellites to serve more and more societal needs, the French Space Agency CNES, which designs the Argos payloads, is innovating and launching the Argos ANGELS project (Argos NEO Generic Economic Light Satellites). ANGELS will lead to a nanosatellite prototype with an Argos NEO instrument (30 cm x 30 cm x 20cm) that will be launched in 2019. In the meantime, the design of the renewal of the Argos constellation, called Argos For Next Generations (Argos4NG), is on track and will be operational in 2022. Based on Argos 4 and benefitting of the feedback from ANGELS project, this constellation will allow revisiting time of fewer than 20 minutes in average between two satellite passes, and will also bring more frequency bands to improve the overall capacity of the system. The presentation will then be an overview of the Argos system, present and future and new capacities coming with it. On top of that, use cases of two Argos hardware modules will be presented: the goniometer pathfinder allowing recovering Argos beacons at sea or on the ground in a 100 km radius horizon-free circle around the beacon location and the new Argos 4 chipset called ‘Artic’, already available and tested by several manufacturers.

Keywords: Argos satellite telemetry, marine protected areas, oceanography, maritime services

Procedia PDF Downloads 182
8927 Sider Bee Honey: Antitumor Effect in Some Experimental Tumor Cell Lines

Authors: Aliaa M. Issa, Mahmoud N. ElRouby, Sahar A. S. Ahmad, Mahmoud M. El-Merzabani

Abstract:

Sider honey is a type of honey produced by bees feeding on the nectar of Sider tree, Ziziphus spina-christi (L) Desf . Honey is an effective agent for preventing, inhibiting and treating the growth of human and animal cancer cell lines in vitro and in vivo. The aim of the present study was to evaluate the impact of different dilutions from crude Sider honey and different duration times of exposure on the growth of six tumor cell lines (human cervical cancer cell line, HeLa; human hepatocellular carcinoma cell line, HepG-2; human larynx carcinoma cell line, Hep-2; brain tumor cell line, U251) as well as one animal cancerous cell line (Ehrlich ascites carcinoma cells line, EAC) and one normal cell line, Homo sapiens, human, (WISH) CCL-25. Different concentrations and treatment durations with Sider honey were tested on the growth of several cancer cell lines types. Histopathological changes in the tumor masses, animal survival, apoptosis and necrosis of the used cancer cell lines (using flow cytometry) were evaluated. Sider honey was administers either to the tumor mass itself by intratumoral injection or via drinking water. One-way ANOVA test was used for the analysis of (the means + standard error) of the optical density obtained from the Elisa reader and flow cytometry. The study revealed that different concentrations of Sider honey affected the growth patterns of all the studied cancer cell lines as well as their histopathological changes, and it depended on the cell line nature and the concentration of honey used. It is obvious that the relative animal survival percentage (bearing Ehrlich ascites carcinoma, EAC cells) was proportionally increased with the increase in the used honey concentrations. The study of apoptosis and necrosis using the flow cytometry technique emphasized the viability results. In conclusion, Sider honey was effective as antitumor agent, in the used concentrations.

Keywords: antitumor, honey, sider, tumor cell lines

Procedia PDF Downloads 538
8926 Effect of Hormones Priming on Enzyme Activity and Lipid Peroxidation in Wheat Seed under Accelerated Aging

Authors: Amin Abbasi, Fariborz Shekari, Seyed Bahman Mousavi

Abstract:

Seed aging during storage is a complex biochemical and physiological processes that can lead to reduce seed germination. This phenomenon associated with increasing of total antioxidant activity during aging. To study the effects of hormones on seed aging, aged wheat seeds (control, 90 and 80% viabilities) were treated with GA3, Salicylic Acid, and paclobutrazol and antioxidant system were investigated as molecular biomarkers for seed vigor. The results showed that, seed priming treatment significantly affected germination percentage, normality seedling percentage, H2O2, MDA, CAT, APX, and GPX activates. Maximum germination percentage achieve in GA3 priming in control treatment. Germination percentage and normal seedling percentage increased in other GA3 priming treatment compared with other hormones. Also aging increased MDA, H2O2 content. MDA is considered sensitive marker commonly used for assessing membrane lipid peroxidation and H2O2result in toxicity to cellular membrane system and damages to plant cells. Amount of H2O2 and MDA declined in GA3 treatment. CAT, GPX and APX activities were reduced by increasing the aging time and at different levels of priming. The highest APX activity was observed in Salicylic Acid control treatment and the highest GPX and CAT activity was obtained in GA3 control treatment. The lowest MDA and H2O2 showed in GA3 control treatment, too. Hormone priming increased Antioxidant enzyme activity and decreased amount of reactive oxygen space and malondialdehyde (MDA) under aging treatment. Also, GA3 priming treatments have a significant effect on germination percentage and number of normal seedling. Generally aging seed, increase ROS and lipid peroxidation. Antioxidant enzymes activity of aged seeds increased after hormone priming.

Keywords: hormones priming, wheat, aging seed, antioxidant, lipid peroxidation

Procedia PDF Downloads 498
8925 Influence of Flexible Plate's Contour on Dynamic Behavior of High Speed Flexible Coupling of Combat Aircraft

Authors: Dineshsingh Thakur, S. Nagesh, J. Basha

Abstract:

A lightweight High Speed Flexible Coupling (HSFC) is used to connect the Engine Gear Box (EGB) with an Accessory Gear Box (AGB) of the combat aircraft. The HSFC transmits the power at high speeds ranging from 10000 to 18000 rpm from the EGB to AGB. The HSFC is also accommodates larger misalignments resulting from thermal expansion of the aircraft engine and mounting arrangement. The HSFC has the series of metallic contoured annular thin cross-sectioned flexible plates to accommodate the misalignments. The flexible plates are accommodating the misalignment by the elastic material flexure. As the HSFC operates at higher speed, the flexural and axial resonance frequencies are to be kept away from the operating speed and proper prediction is required to prevent failure in the transmission line of a single engine fighter aircraft. To study the influence of flexible plate’s contour on the lateral critical speed (LCS) of HSFC, a mathematical model of HSFC as a elven rotor system is developed. The flexible plate being the bending member of the system, its bending stiffness which results from the contoured governs the LCS. Using transfer matrix method, Influence of various flexible plate contours on critical speed is analyzed. In the above analysis, the support bearing flexibility on critical speed prediction is also considered. Based on the study, a model is built with the optimum contour of flexible plate, for validation by experimental modal analysis. A good correlation between the theoretical prediction and model behavior is observed. From the study, it is found that the flexible plate’s contour is playing vital role in modification of system’s dynamic behavior and the present model can be extended for the development of similar type of flexible couplings for its computational simplicity and reliability.

Keywords: flexible rotor, critical speed, experimental modal analysis, high speed flexible coupling (HSFC), misalignment

Procedia PDF Downloads 217
8924 Repeated Batch Cultivation: A Novel Empty and Fill Strategy for the Enhanced Production of a Biodegradable Polymer, Polyhydroxy Alkanoate by Alcaligenes latus

Authors: Geeta Gahlawat, Ashok Kumar Srivastava

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In the present study, a simple drain and fill protocol strategy of repeated batch was adopted for enhancement in polyhydroxyalkanoates (PHAs) production using alcaligenes latus DSM 1124. Repeated batch strategy helped in increasing the longevity of otherwise decaying culture in the bioreactor by supplementing fresh substrates during each cycle of repeated-batch. The main advantages of repeated batch are its ease of operation, enhancement of culture stability towards contamination, minimization of pre-culture effects and maintenance of organism at high growth rates. The cultivation of A. latus was carried out in 7 L bioreactor containing 4 L optimized nutrient medium and a comparison with the batch mode fermentation was done to evaluate the performance of repeated batch in terms of PHAs accumulation and productivity. The statistically optimized medium recipe consisted of: 25 g/L Sucrose, 2.8 g/L (NH4)2SO4, 3.25 g/L KH2PO4, 3.25 g/L Na2HPO4, 0.2 g/L MgSO4, 1.5 mL/L trace element solution. In this strategy, 20% (v/v) of the culture broth was removed from the reactor and supplemented with an equal volume of fresh medium when sucrose concentration inside the reactor decreased below 8 g/L. The fermenter was operated for three repeated batch cycles and fresh nutrient feeding was done at 27 h, 48 h, and 60 h. Repeated batch operation resulted in a total biomass of 27.89 g/L and PHAs concentration 20.55 g/L at the end of 69 h which was a marked improvement as compared to batch cultivation (8.71 g/L biomass and 6.24 g/L PHAs). This strategy demonstrated 3.3 fold and 1.8 fold increase in PHAs concentration and volumetric productivity, respectively as compared to batch cultivation. Repeated batch cultivation strategy had also the benefit of avoiding non-productive time period required for cleaning, refilling and sterilization of bioreactor, thereby increasing the overall volumetric productivity and making the entire process cost-effective too.

Keywords: alcaligenes, biodegradation, polyhydroxyalkanoates, repeated batch

Procedia PDF Downloads 371
8923 Dimensioning of Circuit Switched Networks by Using Simulation Code Based On Erlang (B) Formula

Authors: Ali Mustafa Elshawesh, Mohamed Abdulali

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The paper presents an approach to dimension circuit switched networks and find the relationship between the parameters of the circuit switched networks on the condition of specific probability of call blocking. Our work is creating a Simulation code based on Erlang (B) formula to draw graphs which show two curves for each graph; one of simulation and the other of calculated. These curves represent the relationships between average number of calls and average call duration with the probability of call blocking. This simulation code facilitates to select the appropriate parameters for circuit switched networks.

Keywords: Erlang B formula, call blocking, telephone system dimension, Markov model, link capacity

Procedia PDF Downloads 614
8922 Electronic Physical Activity Record (EPAR): Key for Data Driven Physical Activity Healthcare Services

Authors: Rishi Kanth Saripalle

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Medical experts highly recommend to include physical activity in everyone’s daily routine irrespective of gender or age as it helps to improve various medical issues or curb potential issues. Simultaneously, experts are also diligently trying to provide various healthcare services (interventions, plans, exercise routines, etc.) for promoting healthy living and increasing physical activity in one’s ever increasing hectic schedules. With the introduction of wearables, individuals are able to keep track, analyze, and visualize their daily physical activities. However, there seems to be no common agreed standard for representing, gathering, aggregating and analyzing an individual’s physical activity data from disparate multiple sources (exercise pans, multiple wearables, etc.). This issue makes it highly impractical to develop any data-driven physical activity applications and healthcare programs. Further, the inability to integrate the physical activity data into an individual’s Electronic Health Record to provide a wholistic image of that individual’s health is still eluding the experts. This article has identified three primary reasons for this potential issue. First, there is no agreed standard, both structure and semantic, for representing and sharing physical activity data across disparate systems. Second, various organizations (e.g., LA fitness, Gold’s Gym, etc.) and research backed interventions and programs still primarily rely on paper or unstructured format (such as text or notes) to keep track of the data generated from physical activities. Finally, most of the wearable devices operate in silos. This article identifies the underlying problem, explores the idea of reusing existing standards, and identifies the essential modules required to move forward.

Keywords: electronic physical activity record, physical activity in EHR EIM, tracking physical activity data, physical activity data standards

Procedia PDF Downloads 285
8921 Reconstruction of Womanhood: Narratives of Unmarried Basotho Women in Lesotho

Authors: Neo Mohlabane

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-- Feminists across various contexts have written extensively on the subject of ‘Woman.’ Recently the question of difference; to account for the cultural, ethnic, and racial diversity among women themselves has become a highly contested issue in feminist theories. Tensions have ensued where ‘western feminisms’ have been criticized for bias that is embedded in the objectification of ‘different’ women often regarded as ‘other’; traditional, therefore inferior. Thus, it is argued that womanhood; a set of socially defined attributes appropriate for women, holds different meanings depending on the context in which it is defined. Drawing on decolonial feminist approaches, this qualitative study explored the constructions of ‘womanhood’ from the perspective of unmarried Basotho women in Lesotho, where womanhood is predominantly defined in marital terms. Through the narrated life-stories of twenty unmarried Basotho women, the study revealed that as opposed to the ‘traditional’ definition that accounts for a single attribute woman as ‘wife,’ unmarried Basotho women defined ‘womanhood’ in different ways that deconstructed fixed gendered categories. The women drew meaning from their past personal experiences of childhood to construct and re-construct womanhood in adulthood. By transforming their embodied experiences of hardship and sorrow into valuable constructs with which they self-evaluated as resilient and perseverant, the women constructed a base for self-affirmation as woman. In addition, the women anchored their constructions and reconstructions of woman by transforming the meanings attached to the realms of respectability, sexuality and motherhood. Thus, to the question; what is a Woman? In part, the study concluded that there is no such thing as a ‘unitary’ definition of womanhood, instead Mosotho womanhood has always been and will always be in a state of flux; bearing multiplicity and complexity. This study highlights the need to exercise caution when using western concepts to understand the experiences of women in local African contexts. In order to decolonize feminist scholarship, African feminisms need to re-construct conceptual and theoretical frameworks appropriate for analyzing and understanding gender issues in African contexts.

Keywords: decoloniality, feminism, Lesotho, womanhood

Procedia PDF Downloads 110
8920 Artificial Neural Networks for Cognitive Radio Network: A Survey

Authors: Vishnu Pratap Singh Kirar

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

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

Procedia PDF Downloads 611
8919 The Competitive Power of Supply Chain Quality Management in Manufacturing Companies in Cameroon

Authors: Nicodemus Tiendem, Arrey Mbayong Napoleon

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The heightening of competition and the quest for market share has left business persons and research communities re-examining and reinventing their competitive practices. A case in point is Porter’s generic strategy which has received a lot of criticism lately regarding its inability to maintain a company’s competitive power. This is because it focuses more on the organisation and ignores her external partners, who have a strong bearing on the company’s performance. This paper, therefore, sought to examine Porter’s generic strategies alongside supply chain quality management practices in terms of their effectiveness in building the competitive power of manufacturing companies in Cameroon. This was done with the use of primary data captured from a survey study across the supply chains of 20 manufacturing companies in Cameroon using a five-point Likert scale questionnaire. For each company, four 1st tier suppliers and four 1st tier distributors were carefully chosen to participate in the study alongside the companies themselves. In each case, attention was directed to persons involved in the supply chains of the companies. This gave a total of 180 entities comprising the supply chains of the 20 manufacturing companies involved in the study, making a total of 900 participants. The data was analysed using three multiple regression models to assess the effect of Porter’s generic strategy and supply chain quality management on the marketing performance of the companies. The findings proved that in such a competitive atmosphere, supply chain quality management is a better tool for marketing performance over Porter’s generic strategies and hence building the competitive power of the companies at all levels of the study. Although the study made use of convenience sampling, where sample selectivity biases the results, the findings aligned with many other recent developments in line with building the competitive power of manufacturing companies and thereby made the findings suitable for generalisation.

Keywords: supply chain quality management, Porter’s generic strategies, competitive power, marketing performance, manufacturing companies, Cameroon

Procedia PDF Downloads 89
8918 Oxidation and Reduction Kinetics of Ni-Based Oxygen Carrier for Chemical Looping Combustion

Authors: J. H. Park, R. H. Hwang, K. B. Yi

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Carbon Capture and Storage (CCS) is one of the important technology to reduce the CO₂ emission from large stationary sources such as a power plant. Among the carbon technologies for power plants, chemical looping combustion (CLC) has attracted much attention due to a higher thermal efficiency and a lower cost of electricity. A CLC process is consists of a fuel reactor and an air reactor which are interconnected fluidized bed reactor. In the fuel reactor, an oxygen carrier (OC) is reduced by fuel gas such as CH₄, H₂, CO. And the OC is send to air reactor and oxidized by air or O₂ gas. The oxidation and reduction reaction of OC occurs between the two reactors repeatedly. In the CLC system, high concentration of CO₂ can be easily obtained by steam condensation only from the fuel reactor. It is very important to understand the oxidation and reduction characteristics of oxygen carrier in the CLC system to determine the solids circulation rate between the air and fuel reactors, and the amount of solid bed materials. In this study, we have conducted the experiment and interpreted oxidation and reduction reaction characteristics via observing weight change of Ni-based oxygen carrier using the TGA with varying as concentration and temperature. Characterizations of the oxygen carrier were carried out with BET, SEM. The reaction rate increased with increasing the temperature and increasing the inlet gas concentration. We also compared experimental results and adapted basic reaction kinetic model (JMA model). JAM model is one of the nucleation and nuclei growth models, and this model can explain the delay time at the early part of reaction. As a result, the model data and experimental data agree over the arranged conversion and time with overall variance (R²) greater than 98%. Also, we calculated activation energy, pre-exponential factor, and reaction order through the Arrhenius plot and compared with previous Ni-based oxygen carriers.

Keywords: chemical looping combustion, kinetic, nickel-based, oxygen carrier, spray drying method

Procedia PDF Downloads 210