Search results for: mass flow ratio
2652 Role of Human Epididymis Protein 4 as a Biomarker in the Diagnosis of Ovarian Cancer
Authors: Amar Ranjan, Julieana Durai, Pranay Tanwar
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Background &Introduction: Ovarian cancer is one of the most common malignant tumor in the female. 70% of the cases of ovarian cancer are diagnosed at an advanced stage. The five-year survival rate associated with ovarian cancer is less than 30%. The early diagnosis of ovarian cancer becomes a key factor in improving the survival rate of patients. Presently, CAl25 (carbohydrate antigen125) is used for the diagnosis and therapeutic monitoring of ovarian cancer, but its sensitivity and specificity is not ideal. The introduction of HE4, human epididymis protein 4 has attracted much attention. HE4 has a sensitivity and specificity of 72.9% and 95% for differentiating between benign and malignant adnexal masses, which is better than CA125 detection. Methods: Serum HE4 and CA -125 were estimated using the chemiluminescence method. Our cases were 40 epithelial ovarian cancer, 9 benign ovarian tumor, 29 benign gynaecological diseases and 13 healthy individuals. This group include healthy woman those who have undergoing family planning and menopause-related medical consultations and they are negative for ovarian mass. Optimal cut off values for HE4 and CA125 were 55.89pmol/L and 40.25U/L respectively (determined by statistical analysis). Results: The level of HE4 was raised in all ovarian cancer patients (n=40) whereas CA125 levels were normal in 6/40 ovarian cancer patients, which were the cases of OC confirmed by histopathology. There is a significant decrease in the level of HE4 with comparison to CA125 in benign ovarian tumor cases. Both the levels of HE4 and CA125 were raised in the nonovarian cancer group, which includes cancer of endometrium and cervix. In the healthy group, HE4 was normal in all patients except in one case of the rudimentary horn, and the reason for this raised HE4 level is due to the incomplete development of uterus whereas CA125 was raised in 3 cases. Conclusions: Findings showed that the serum level of HE4 is an important indicator in the diagnosis of ovarian cancer, and it also distinguishes between benign and malignant pelvic masses. However, a combination of HE4 and CA125 panel will be extremely valuable in improving the diagnostic efficiency of ovarian cancer. These findings of our study need to be validated in the larger cohort of patients.Keywords: human epididymis protein 4, ovarian cancer, diagnosis, benign lesions
Procedia PDF Downloads 1332651 Zeolite Supported Iron-Sensitized TIO₂ for Tetracycline Photocatalytic Degradation under Visible Light: A Comparison between Doping and Ion Exchange
Authors: Ghadeer Jalloul, Nour Hijazi, Cassia Boyadjian, Hussein Awala, Mohammad N. Ahmad, Ahmad Albadarin
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In this study, we applied Fe-sensitized TiO₂ supported over embryonic Beta zeolite (BEA) zeolite for the photocatalytic degradation of Tetracycline (TC) antibiotic under visible light. Four different samples having 20, 40, 60, and 100% w/w as a ratio of TiO₂/BEA were prepared. The immobilization of solgel TiO₂ (33 m²/g) over BEA (390 m²/g) increased its surface area to (227 m²/g) and enhanced its adsorption capacity from 8% to 19%. To expand the activity of TiO₂ photocatalyst towards the visible light region (λ>380 nm), we explored two different metal sensitization techniques with Iron ions (Fe³⁺). In the ion-exchange method, the substitutional cations in the zeolite in TiO₂/BEA were exchanged with (Fe³⁺) in an aqueous solution of FeCl₃. In the doping technique, solgel TiO₂ was doped with (Fe³⁺) from FeCl₃ precursor during its synthesis and before its immobilization over BEA. (Fe-TiO₂/BEA) catalysts were characterized using SEM, XRD, BET, UV-VIS DRS, and FTIR. After testing the performance of the various ion-exchanged catalysts under blue and white lights, only (Fe-TiO₂/BEA 60%) showed better activity as compared to pure TiO₂ under white light with 100 ppm initial catalyst concentration and 20 ppm TC concentration. As compared to ion-exchanged (Fe-TiO₂/BEA), doped (Fe-TiO₂/BEA) resulted in higher photocatalytic efficiencies under blue and white lights. The 3%-Fe-doped TiO₂/BEA removed 92% of TC compared to 54% by TiO₂ under white light. The catalysts were also tested under real solar irradiations. This improvement in the photocatalytic performance of TiO₂ was due to its higher adsorption capacity due to BEA support combined with the presence of Iron ions that enhance the visible light absorption and minimize the recombination effect by the charge carriers. Keywords: Tetracycline, photocatalytic degradation, immobilized TiO₂, zeolite, iron-doped TiO₂, ion-exchange
Procedia PDF Downloads 1112650 The Role of the Linguistic Mediator in Relation to Culturally Oriented Crimes
Authors: Andreas Aceranti, Simonetta Vernocchi, Elisabetta Aldrovandi, Marco Colorato, Carolina Ascrizzi
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Nowadays, especially due to an increasing flow of migration and uncontrolled globalisation, linguistic, cultural and religious differences can be a major obstacle for people belonging to different ethnic groups. Each group has its own traditional background, which, in addition to its positive aspects, also includes extremely unpleasant and dramatic situations: culture-related crimes. We analysed several cases belonging to this category of crime which is becoming more and more present in Europe, creating not only a strong social rift dictated by the misunderstanding between migrants and host populations but also by the isolation and ghettoisation of subjects classified as 'different'. Such social rejection, in fact, represents a great source of stress and frustration for those who seek to be part of the community and can generate phenomena of rebellion that result in violent acts. Similar situations must be addressed by the figure of the cultural-linguistic mediator who, thanks to his or her multidisciplinary knowledge, assumes the role of a 'bridge', thus helping the process of awareness and understanding within the social group through the use of various tools, including awareness-raising campaigns and interventions in both the school and social-health sectors. By analysing how the notions of culture and offense have evolved throughout history until they have merged into a single principle and, secondly, how the figure of the language mediator represents a fundamental role in the resolution of conflicts related to cultural diversity has helped us define the basis for new protocols in dealing with such crimes. Especially we have to define the directions of further investigations that we will carry out in the next months.Keywords: cultural crimes, hatred crimes, immigration, cultural mediation
Procedia PDF Downloads 802649 Simulation of Cure Kinetics and Process-Induced Stresses in Carbon Fibre Composite Laminate Manufactured by a Liquid Composite Molding Technique
Authors: Jayaraman Muniyappan, Bachchan Kr Mishra, Gautam Salkar, Swetha Manian Sridhar
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Vacuum Assisted Resin Transfer Molding (VARTM), a cost effective method of Liquid Composite Molding (LCM), is a single step process where the resin, at atmospheric pressure, is infused through a preform that is maintained under vacuum. This hydrodynamic pressure gradient is responsible for the flow of resin through the dry fabric preform. The current study has a slight variation to traditional VARTM, wherein, the resin infuses through the fabric placed on a heated mold to reduce its viscosity. The saturated preform is subjected to a cure cycle where the resin hardens as it undergoes curing. During this cycle, an uneven temperature distribution through the thickness of the composite and excess exothermic heat released due to different cure rates result in non-uniform curing. Additionally, there is a difference in thermal expansion coefficient between fiber and resin in a given plane and between adjacent plies. All these effects coupled with orthotropic coefficient of thermal expansion of the composite give rise to process-induced stresses in the laminate. Such stresses lead to part deformation when the laminate tries to relieve them as the part is released off the mold. The current study looks at simulating resin infusion, cure kinetics and the structural response of composite laminate subject to process-induced stresses.Keywords: cure kinetics, process-induced stresses, thermal expansion coefficient, vacuum assisted resin transfer molding
Procedia PDF Downloads 2402648 Temporal and Spatial Distribution Prediction of Patinopecten yessoensis Larvae in Northern China Yellow Sea
Authors: RuiJin Zhang, HengJiang Cai, JinSong Gui
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It takes Patinopecten yessoensis larvae more than 20 days from spawning to settlement. Due to the natural environmental factors such as current, Patinopecten yessoensis larvae are transported to a distance more than hundreds of kilometers, leading to a high instability of their spatial and temporal distribution and great difficulties in the natural spat collection. Therefore predicting the distribution is of great significance to improve the operating efficiency of the collecting. Hydrodynamic model of Northern China Yellow Sea was established and the motions equations of physical oceanography and verified by the tidal harmonic constants and the measured data velocities of Dalian Bay. According to the passivity drift characteristics of the larvae, combined with the hydrodynamic model and the particle tracking model, the spatial and temporal distribution prediction model was established and the spatial and temporal distribution of the larvae under the influence of flow and wind were simulated. It can be concluded from the model results: ocean currents have greatest impacts on the passive drift path and diffusion of Patinopecten yessoensis larvae; the impact of wind is also important, which changed the direction and speed of the drift. Patinopecten yessoensis larvae were generated in the sea along Zhangzi Island and Guanglu-Dachangshan Island, but after two months, with the impact of wind and currents, the larvae appeared in the west of Dalian and the southern of Lvshun, and even in Bohai Bay. The model results are consistent with the relevant literature on qualitative analysis, and this conclusion explains where the larvae come from in the perspective of numerical simulation.Keywords: numerical simulation, Patinopecten yessoensis larvae, predicting model, spatial and temporal distribution
Procedia PDF Downloads 3062647 Optimal Parameters of Two-Color Ionizing Laser Pulses for Terahertz Generation
Authors: I. D. Laryushin, V. A. Kostin, A. A. Silaev, N. V. Vvedenskii
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Generation of broadband intense terahertz (THz) radiation attracts reasonable interest due to various applications, such as the THz time-domain spectroscopy, the probing and control of various ultrafast processes, the THz imaging with subwavelength resolution, and many others. One of the most promising methods for generating powerful and broadband terahertz pulses is based on focusing two-color femtosecond ionizing laser pulses in gases, including ambient air. For this method, the amplitudes of terahertz pulses are determined by the free-electron current density remaining in a formed plasma after the passage of the laser pulse. The excitation of this residual current density can be treated as multi-wave mixing: Аn effective generation of terahertz radiation is possible only when the frequency ratio of one-color components in the two-color pulse is close to irreducible rational fraction a/b with small odd sum a + b. This work focuses on the optimal parameters (polarizations and intensities) of laser components for the strongest THz generation. The optimal values of parameters are found numerically and analytically with the use of semiclassical approach for calculating the residual current density. For frequency ratios close to a/(a ± 1) with natural a, the strongest THz generation is shown to take place when the both laser components have circular polarizations and equal intensities. For this optimal case, an analytical formula for the residual current density was derived. For the frequency ratios such as 2/5, the two-color ionizing pulses with circularly polarized components practically do not excite the residual current density. However, the optimal parameters correspond generally to specific elliptical (not linear) polarizations of the components and intensity ratios close to unity.Keywords: broadband terahertz radiation, ionization, laser plasma, ultrashort two-color pulses
Procedia PDF Downloads 2122646 Growth and Nutrient Utilization of Some Citrus Peels and Vitamin Premix as Additives in Clarias Gariepinus Diets
Authors: Eunice Oluwayemisi Adeparusi, Mary Adedolapo Ijadeyila
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The study was carried out at the Federal University of Technology, Akure, Nigeria, West Africa. Seven set of diets were prepared comprising of two sets. The first set consisted of a combination of three diets from a combination of two different citrus peels from Orange (Citrus sinesis), Tangerine (Citrus tangerina / Citrus reticulata) and Tangelo (Citrus tangelo a hybrid of Citrus reticulata and Citrus maxima) at 50:50 while the other three consisted f50:50. Diet with 100% vitamin premix served as the control. Air-dried citrus peels were added in a 40% crude protein diet for the juveniles (4.49±0.05g) Clarias gariepinus. The experiment was carried out for a period of 56 days in triplicate trials. Fish were randomly distributed into twenty-one tanks at ten fish per tanks. The feed was extruded and fed to satiation twice daily. The result shows that fish fed Tangelo and Tangerine (TGL-TGR) had the best growth response in terms of final weight, specific growth rate, feed conversion ratio and feed utilization efficiency when compared with other diets. The FCR of fish in the diet ranges from 0.93-1.62. Fish fed the mixture of Orange peel and Vitamin-mineral premix (ORG-VIT) and those on Tangelo and Vitamin-mineral premix (TGL-VIT) had higher survival rate. There were significant differences (P<0.05) in the mean final weight, weight gain and specific growth rate. The result shows that citrus peels enhance the growth performance and feed utilization of the juvenile of African mud catfish, thereby reducing the cost of fish production.Keywords: African mud catfish, growth, citrus peels, vitamin-mineral premix, nutrient utilization, additives
Procedia PDF Downloads 832645 Formulation and Optimization of Topical 5-Fluorouracil Microemulsions Using Central Compisite Design
Authors: Sudhir Kumar, V. R. Sinha
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Water in oil topical microemulsions of 5-FU were developed and optimized using face centered central composite design. Topical w/o microemulsion of 5-FU were prepared using sorbitan monooleate (Span 80), polysorbate 80 (Tween 80), with different oils such as oleic acid (OA), triacetin (TA), and isopropyl myristate (IPM). The ternary phase diagrams designated the microemulsion region and face centered central composite design helped in determining the effects of selected variables viz. type of oil, smix ratio and water concentration on responses like drug content, globule size and viscosity of microemulsions. The CCD design exhibited that the factors have statistically significant effects (p<0.01) on the selected responses. The actual responses showed excellent agreement with the predicted values as suggested by the CCD with lower residual standard error. Similarly, the optimized values were found within the range as predicted by the model. Furthermore, other characteristics of microemulsions like pH, conductivity were investigated. For the optimized microemulsion batch, ex-vivo skin flux, skin irritation and retention studies were performed and compared with marketed 5-FU formulation. In ex vivo skin permeation studies, higher skin retention of drug and minimal flux was achieved for optimized microemulsion batch then the marketed cream. Results confirmed the actual responses to be in agreement with predicted ones with least residual standard errors. Controlled release of drug was achieved for the optimized batch with higher skin retention of 5-FU, which can further be utilized for the treatment of many dermatological disorders.Keywords: 5-FU, central composite design, microemulsion, ternanry phase diagram
Procedia PDF Downloads 4802644 Improving Waste Recycling and Resource Productivity by Integrating Smart Resource Tracking System
Authors: Atiq Zaman
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The high contamination rate in the recycling waste stream is one of the major problems in Australia. In addition, a lack of reliable waste data makes it even more difficult for designing and implementing an effective waste management plan. This article conceptualizes the opportunity to improve resource productivity by integrating smart resource tracking system (SRTS) into the Australian household waste management system. The application of the smart resource tracking system will be implemented through the following ways: (i) mobile application-based resource tracking system used to measure the household’s material flow; (ii) RFID, smart image and weighing system used to track waste generation, recycling and contamination; (iii) informing and motivating manufacturer and retailers to improve their problematic products’ packaging; and (iv) ensure quality and reliable data through open-sourced cloud data for public use. The smart mobile application, imaging, radio-frequency identification (RFID) and weighing technologies are not new, but the very straightforward idea of using these technologies in the household resource consumption, waste bins and collection trucks will open up a new era of accurately measuring and effectively managing our waste. The idea will bring the most urgently needed reliable, data and clarity on household consumption, recycling behaviour and waste management practices in the context of available local infrastructure and policies. Therefore, the findings of this study would be very important for decision makers to improve resource productivity in the waste industry by using smart resource tracking system.Keywords: smart devices, mobile application, smart sensors, resource tracking, waste management, resource productivity
Procedia PDF Downloads 1482643 Cost Analysis of Neglected Tropical Disease in Nigeria: Implication for Programme Control and Elimination
Authors: Lawong Damian Bernsah
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Neglected Tropical Diseases (NTDs) are most predominant among the poor and rural populations and are endemic in 149 countries. These diseases are the most prevalent and responsible for infecting 1.4 billion people worldwide. There are 17 neglected tropical diseases recognized by WHO that constitute the fourth largest disease health and economic burden of all communicable diseases. Five of these 17 diseases are considered for the cost analysis of this paper: lymphatic filariasis, onchocerciasis, trachoma, schistosomiasis, and soil transmitted helminth infections. WHO has proposed a roadmap for eradication and elimination by 2020 and treatments have been donated through the London Declaration by pharmaceutical manufacturers. The paper estimates the cost of NTD control programme and elimination for each NTD disease and total in Nigeria. This is necessary as it forms the bases upon which programme budget and expenditure could be based. Again, given the opportunity cost the resources for NTD face it is necessary to estimate the cost so as to provide bases for comparison. Cost of NTDs control and elimination programme is estimated using the population at risk for each NTD diseases and for the total. The population at risk is gotten from the national master plan for the 2015 - 2020, while the cost per person was gotten for similar studies conducted in similar settings and ranges from US$0.1 to US$0.5 for Mass Administration of Medicine (MAM) and between US$1 to US$1.5 for each NTD disease. The combined cost for all the NTDs was estimated to be US$634.88 million for the period 2015-2020 and US$1.9 billion for each NTD disease for the same period. For the purpose of sensitivity analysis and for robustness of the analysis the cost per person was varied and all were still high. Given that health expenditure for Nigeria (% of GDP) averages 3.5% for the period 1995-2014, it is very clear that efforts have to be made to improve allocation to the health sector in general which is hoped could trickle to NTDs control and elimination. Thus, the government and the donor partners would need to step-up budgetary allocation and also to be aware of the costs of NTD control and elimination programme since they have alternative uses. Key Words: Neglected Tropical Disease, Cost Analysis, NTD Programme Control and Elimination, Cost per PersonKeywords: Neglected Tropical Disease, Cost Analysis, Neglected Tropical Disease Programme Control and Elimination, Cost per Person
Procedia PDF Downloads 2762642 Drilling Quantification and Bioactivity of Machinable Hydroxyapatite : Yttrium phosphate Bioceramic Composite
Authors: Rupita Ghosh, Ritwik Sarkar, Sumit K. Pal, Soumitra Paul
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The use of Hydroxyapatite bioceramics as restorative implants is widely known. These materials can be manufactured by pressing and sintering route to a particular shape. However machining processes are still a basic requirement to give a near net shape to those implants for ensuring dimensional and geometrical accuracy. In this context, optimising the machining parameters is an important factor to understand the machinability of the materials and to reduce the production cost. In the present study a method has been optimized to produce true particulate drilled composite of Hydroxyapatite Yttrium Phosphate. The phosphates are used in varying ratio for a comparative study on the effect of flexural strength, hardness, machining (drilling) parameters and bioactivity.. The maximum flexural strength and hardness of the composite that could be attained are 46.07 MPa and 1.02 GPa respectively. Drilling is done with a conventional radial drilling machine aided with dynamometer with high speed steel (HSS) and solid carbide (SC) drills. The effect of variation in drilling parameters (cutting speed and feed), cutting tool, batch composition on torque, thrust force and tool wear are studied. It is observed that the thrust force and torque varies greatly with the increase in the speed, feed and yttrium phosphate content in the composite. Significant differences in the thrust and torque are noticed due to the change of the drills as well. Bioactivity study is done in simulated body fluid (SBF) upto 28 days. The growth of the bone like apatite has become denser with the increase in the number of days for all the composition of the composites and it is comparable to that of the pure hydroxyapatite.Keywords: Bioactivity, Drilling, Hydroxyapatite, Yttrium Phosphate
Procedia PDF Downloads 3012641 Impact of External Temperature on the Speleothem Growth in the Moravian Karst
Authors: Frantisek Odvarka
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Based on the data from the Moravian Karst, the influence of the calcite speleothem growth by selected meteorological factors was evaluated. External temperature was determined as one of the main factors influencing speleothem growth in Moravian Karst. This factor significantly influences the CO₂ concentration in soil/epikarst, and cave atmosphere in the Moravian Karst and significantly contributes to the changes in the CO₂ partial pressure differences between soil/epikarst and cave atmosphere in Moravian Karst, which determines the drip water supersaturation with respect to the calcite and quantity of precipitated calcite in the Moravian Karst cave environment. External air temperatures and cave air temperatures were measured using a COMET S3120 data logger, which can measure temperatures in the range from -30 to +80 °C with an accuracy of ± 0.4 °C. CO₂ concentrations in the cave and soils were measured with a FT A600 CO₂H Ahlborn probe (value range 0 ppmv to 10,000 ppmv, accuracy 1 ppmv), which was connected to the data logger ALMEMO 2290-4, V5 Ahlborn. The soil temperature was measured with a FHA646E1 Ahlborn probe (temperature range -20 to 70 °C, accuracy ± 0.4 °C) connected to an ALMEMO 2290-4 V5 Ahlborn data logger. The airflow velocities into and out of the cave were monitored by a FVA395 TH4 Thermo anemometer (speed range from 0.05 to 2 m s⁻¹, accuracy ± 0.04 m s⁻¹), which was connected to the ALMEMO 2590-4 V5 Ahlborn data logger for recording. The flow was measured in the lower and upper entrance of the Imperial Cave. The data were analyzed in MS Office Excel 2019 and PHREEQC.Keywords: speleothem growth, carbon dioxide partial pressure, Moravian Karst, external temperature
Procedia PDF Downloads 1452640 Removal of Diesel by Soil Washing Technologies Using a Non-Ionic Surfactant
Authors: Carolina Guatemala, Josefina Barrera
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A large number of soils highly polluted with recalcitrant hydrocarbons and the limitation of the current bioremediation methods continue being the drawback for an efficient recuperation of these under safe conditions. In this regard, soil washing by degradable surfactants is an alternative option knowing the capacity of surfactants to desorb oily organic compounds. The aim of this study was the establishment of the washing conditions of a soil polluted with diesel, using a nonionic surfactant. A soil polluted with diesel was used. This was collected near to a polluted railway station zone. The soil was dried at room temperature and sieved to a mesh size 10 for its physicochemical and biological characterization. Washing of the polluted soil was performed with surfactant solutions in a 1:5 ratio (5g of soil per 25 mL of the surfactant solution). This was carried out at 28±1 °C and 150 rpm for 72 hours. The factors tested were the Tween 80 surfactant concentration (1, 2, 5 and 10%) and the treatment time. Residual diesel concentration was determined every 24 h. The soil was of a sandy loam texture with a low concentration of organic matter (3.68%) and conductivity (0.016 dS.m- 1). The soil had a pH of 7.63 which was slightly alkaline and a Total Petroleum Hydrocarbon content (TPH) of 11,600 ± 1058.38 mg/kg. The high TPH content could explain the low microbial count of 1.1105 determined as UFC per gram of dried soil. Within the range of the surfactant concentration tested for washing the polluted soil under study, TPH removal increased proportionally with the surfactant concentration. 5080.8 ± 422.2 ppm (43.8 ± 3.64 %) was the maximal concentration of TPH removed after 72 h of contact with surfactant pollution at 10%. Despite the high percentage of hydrocarbons removed, it is assumed that a higher concentration of these could be removed if the washing process is extended or is carried out by stages. Soil washing through the use of surfactants as a desorbing agent was found to be a viable and effective technology for the rapid recovery of soils highly polluted with recalcitrant hydrocarbons.Keywords: diesel, hydrocarbons, soil washing, tween 80
Procedia PDF Downloads 1432639 Simulation Aided Life Cycle Sustainability Assessment Framework for Manufacturing Design and Management
Authors: Mijoh A. Gbededo, Kapila Liyanage, Ilias Oraifige
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Decision making for sustainable manufacturing design and management requires critical considerations due to the complexity and partly conflicting issues of economic, social and environmental factors. Although there are tools capable of assessing the combination of one or two of the sustainability factors, the frameworks have not adequately integrated all the three factors. Case study and review of existing simulation applications also shows the approach lacks integration of the sustainability factors. In this paper we discussed the development of a simulation based framework for support of a holistic assessment of sustainable manufacturing design and management. To achieve this, a strategic approach is introduced to investigate the strengths and weaknesses of the existing decision supporting tools. Investigation reveals that Discrete Event Simulation (DES) can serve as a rock base for other Life Cycle Analysis frameworks. Simio-DES application optimizes systems for both economic and competitive advantage, Granta CES EduPack and SimaPro collate data for Material Flow Analysis and environmental Life Cycle Assessment, while social and stakeholders’ analysis is supported by Analytical Hierarchy Process, a Multi-Criteria Decision Analysis method. Such a common and integrated framework creates a platform for companies to build a computer simulation model of a real system and assess the impact of alternative solutions before implementing a chosen solution.Keywords: discrete event simulation, life cycle sustainability analysis, manufacturing, sustainability
Procedia PDF Downloads 2802638 Influences of Separation of the Boundary Layer in the Reservoir Pressure in the Shock Tube
Authors: Bruno Coelho Lima, Joao F.A. Martos, Paulo G. P. Toro, Israel S. Rego
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The shock tube is a ground-facility widely used in aerospace and aeronautics science and technology for studies on gas dynamic and chemical-physical processes in gases at high-temperature, explosions and dynamic calibration of pressure sensors. A shock tube in its simplest form is comprised of two separate tubes of equal cross-section by a diaphragm. The diaphragm function is to separate the two reservoirs at different pressures. The reservoir containing high pressure is called the Driver, the low pressure reservoir is called Driven. When the diaphragm is broken by pressure difference, a normal shock wave and non-stationary (named Incident Shock Wave) will be formed in the same place of diaphragm and will get around toward the closed end of Driven. When this shock wave reaches the closer end of the Driven section will be completely reflected. Now, the shock wave will interact with the boundary layer that was created by the induced flow by incident shock wave passage. The interaction between boundary layer and shock wave force the separation of the boundary layer. The aim of this paper is to make an analysis of influences of separation of the boundary layer in the reservoir pressure in the shock tube. A comparison among CDF (Computational Fluids Dynamics), experiments test and analytical analysis were performed. For the analytical analysis, some routines in Python was created, in the numerical simulations (Computational Fluids Dynamics) was used the Ansys Fluent, and the experimental tests were used T1 shock tube located in IEAv (Institute of Advanced Studies).Keywords: boundary layer separation, moving shock wave, shock tube, transient simulation
Procedia PDF Downloads 3162637 Using E-learning in a Tertiary Institution during Community Outbreak of COVID-19 in Hong Kong
Authors: Susan Ka Yee Chow
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The Coronavirus disease (COVID-19) reached Hong Kong in 2019 resulting in epidemic in late January 2020. Considering the epidemic development, tertiary institutions made announcements that all on-campus classes were suspended since 01/29/2020. In Tung Wah College, e-learning was adopted in all courses for all programmes. For the undergraduate nursing students, the contact hours and curriculum are bounded by the Nursing Council of Hong Kong to ensure core competence after graduation. Unlike the usual e-learning where students are allowed having flexibility of time and place in their learning, real time learning mode using Blackboard was used to mimic the actual classroom learning environment. Students were required to attend classes according to the timetable using online platform. For lectures, voice over PowerPoint file was the initial step for mass lecturing. Real time lecture was then adopted to improve interactions between teacher and students. Post-lecture quizzes were developed to monitor the effectiveness of lecture delivery. The seminars and tutorials were conducted using real time mode where students were separated into small groups with interactive discussions with teacher within the group. Live time demonstrations were conducted during laboratory sessions. All teaching sessions were audio/video recorded for students’ referral. The assessments including seminar presentation and debate were retained. The learning mode creates an atmosphere for students to display the visual, audio and written works in a non-threatening atmosphere. Other students could comment using text or direct voice as they desired. Real time online learning is the pedagogy to replace classroom contacts in the emergent and unforeseeable circumstances. The learning pace and interaction between students and students with teacher are maintained. The learning mode has the advantage of creating an effective and beneficial learning experience.Keywords: e-learning, nursing curriculum, real time mode, teaching and learning
Procedia PDF Downloads 1172636 Risk Reassessment Using GIS Technologies for the Development of Emergency Response Management Plans for Water Treatment Systems
Authors: Han Gul Lee
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When water treatments utilities are designed, an initial construction site risk assessment is conducted. This helps us to understand general safety risks that each utility needs to be complemented in the designing stage. Once it’s built, an additional risk reassessment process secures and supplements its disaster management and response plan. Because of its constantly changing surroundings with city renovation and developments, the degree of various risks that each facility has to face changes. Therefore, to improve the preparedness for spill incidents or disasters, emergency managers should run spill simulations with the available scientific technologies. This research used a two-dimensional flow routing model to simulate its spill disaster scenario based on its digital elevation model (DEM) collected with drone technologies. The results of the simulations can help emergency managers to supplement their response plan with concrete situational awareness in advance. Planning based on this simulation model minimizes its potential loss and damage when an incident like earthquakes man-made disaster happens, which could eventually be a threat in a public health context. This pilot research provides an additional paradigm to increase the preparedness to spill disasters. Acknowledgment: This work was supported by Korea Environmental Industry & Technology Institute (KEITI) through Environmental R&D Project on the Disaster Prevention of Environmental Facilities Program funded by Korea Ministry of Environment (MOE) (No.202002860001).Keywords: risk assessment, disaster management, water treatment utilities, situational awareness, drone technologies
Procedia PDF Downloads 1462635 Cryptographic Resource Allocation Algorithm Based on Deep Reinforcement Learning
Authors: Xu Jie
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As a key network security method, cryptographic services must fully cope with problems such as the wide variety of cryptographic algorithms, high concurrency requirements, random job crossovers, and instantaneous surges in workloads. Its complexity and dynamics also make it difficult for traditional static security policies to cope with the ever-changing situation. Cyber Threats and Environment. Traditional resource scheduling algorithms are inadequate when facing complex decision-making problems in dynamic environments. A network cryptographic resource allocation algorithm based on reinforcement learning is proposed, aiming to optimize task energy consumption, migration cost, and fitness of differentiated services (including user, data, and task security) by modeling the multi-job collaborative cryptographic service scheduling problem as a multi-objective optimized job flow scheduling problem and using a multi-agent reinforcement learning method, efficient scheduling and optimal configuration of cryptographic service resources are achieved. By introducing reinforcement learning, resource allocation strategies can be adjusted in real-time in a dynamic environment, improving resource utilization and achieving load balancing. Experimental results show that this algorithm has significant advantages in path planning length, system delay and network load balancing and effectively solves the problem of complex resource scheduling in cryptographic services.Keywords: cloud computing, cryptography on-demand service, reinforcement learning, workflow scheduling
Procedia PDF Downloads 182634 Performance Evaluation of Diverging Diamond Interchange Compared to Single Point Diamond Interchange in Riyadh City
Authors: Maged A. Mogalli, Abdullah I. Al-Mansour, Seongkwan Mark Lee
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In the last decades, population growth has gradually exceeded transportation infrastructure growth, and today’s transportation professionals are facing challenge on how to meet the mobility needs of a rising population especially in the absence of adequate public transport, as is the case in Saudi Arabia. The traffic movement congestion can be decreased by carrying out some appropriate alternative designs of interchanges such as diverging diamond interchange (DDI) and single diamond interchange (SPDI). In this paper, evaluation of newly implemented DDIs at the interchange of Makkah road with Prince Turki road and the interchange of King Khaled road with Prince Saud Ibn Mohammed Ibn Mugrin road in Riyadh city was carried out. The comparison between the DDI and SPDI is conducted by evaluating different measures of effectiveness (MOE) such as stop delay, average queue length, and number of stops. In this connection, each interchange type was evaluated for traffic flow at peak hours using micro-simulation program namely 'Synchro/SimTarffic' to measure its effectiveness such as stop delay, average queue length, and number of stops. The results of this study show that DDI provides a better result when compared with SPDI in terms of stope delay, average queue length, and number of stops. The stop delay for the SPDI is greater than DDI by three times. Also, the average queue length is approximately twice that of the SPDI when compared to the DDI. Furthermore, the number of stops for the SPDI is about twice as the DDI.Keywords: single point diamond interchange, diverging diamond interchange, measures of effectiveness, simulation
Procedia PDF Downloads 2622633 Prevalence and Associated Factors of Stunting among 6-59 Months Children in Pastoral Community of Korahay Zone, Somali Regional State, Ethiopia 2016
Authors: Sisay Shine, Frew Tadesse, Zemenu Shiferaw, Lema Mideksa
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Background: Stunting is one of the most important public health problems in Ethiopia with an estimated 44.4% of children less than five years of age are stunted. Thus, this study aimed to assess prevalence and associated factors of stunting among 6-59 months children in pastoral community of Korahay Zone, Somali Regional State, Ethiopia. Objective of the study: To assess prevalence and associated factors of stunting among 6-59 months children in pastoral community of Korahay Zone, Somali Regional State, Ethiopia, 2016. Methods: Community based cross sectional study design was done among 770 children in pastoral community of Korahay Zone. Systematic sampling techniques were used to select households and took child mother pair from each selected households. Data was collected using pre-tested and structured questionnaire. Odds ratio with 95% confidence interval was used to assess level of significance. Result: Prevalence of stunting among 6-59 months age children was 31.9%. Sex (AOR: 1.47, 95%CI 1.02, 2.11), age (AOR: 2.10, 95%CI 1.16, 3.80), maternal education (AOR: 3.42, 95%CI 1.58, 7.41), maternal occupation (AOR: 3.10, 95%CI 1.85, 5.19), monthly income (AOR: 1.47, 95%CI 1.03, 2.09), PNC visits (AOR: 1.59, 95%CI 1.07, 2.37), source of water (AOR: 3.41, 95%CI 1.96, 5.93), toilet availability (AOR: 1.71, 95%CI 1.13, 2.58), first milk feeding (AOR: 3.37, 95%CI 2.27, 5.02) and bottle feeding (AOR: 2.07, 95%CI 1.34, 3.18) were significant predictors of stunting. Conclusion and recommendations: Prevalence of stunting among 6-59 months children was high 31.9%. Lack maternal education, not feeding first milk, unsafe water supply, absence toilet availability and bottle feeding can increase the risk of stunting. So, educating mothers on child feeding practice, sanitation and important of first milk can reduce stunting.Keywords: dietary, environmental, healthcare, socio-demographic, stunting
Procedia PDF Downloads 5812632 Ambient Electrospray Deposition: An Efficient Technique to Immobilize Laccase on Cheap Electrodes With Unprecedented Reuse and Storage Performances
Authors: Mattea Carmen Castrovilli, Antonella Cartoni
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Electrospray ionisation (ESI), a well-established technique widely used to produce ion beams of biomolecules in mass spectrometry (ESI-MS), can be used for ambient soft landing of enzymes on a specific substrate. In this work, we show how the ambient electrospray deposition (ESD) technique can be successfully exploited for manufacturing a promising, green-friendly electrochemical amperometric laccase-based biosensor with unprecedented reuse and storage performance. These biosensors have been manufactured by spraying a laccase solution of 2μg/μL at 20% of methanol on a commercial carbon screen printed electrode (C-SPE) using a custom ESD set-up. The laccase-based ESD biosensor has been tested against catechol compounds in the linear range 2-100 μM, with a limit of detection of 1.7 μM, without interference from cadmium, chrome, arsenic, and zinc and without any memory effects, but showing a matrix effect in lake and well water. The ESD biosensor shows enhanced performances compared to the ones fabricated with other immobilization methods, like drop-casting. Indeed, it retains 100% activity up to two months of storage at ambient conditions without any special care and working stability up to 63 measurements on the same electrode just prepared and 20 on a one-year-old electrode subjected to redeposition together with a 100% resistance to use of the same electrode in subsequent days. The ESD method is a one-step, environmentally friendly method that allows the deposition of the bio-recognition layer without using any additional chemicals. The promising results in terms of storage and working stability also obtained with the more fragile lactate oxidase enzyme suggest these improvements should be attributed to the ESD technique rather than to the bioreceptor, highlighting how the ESD could be useful in reducing pollution from disposable devices. Acknowledgment: The understanding at the molecular level of this promising biosensor by using different spectroscopies, microscopies and analytical techniques is the subject of our PRIN 2022 project ESILARANTE.Keywords: reuse, storage performance, immobilization, electrospray deposition, biosensor, laccase, catechol detection, green chemistry
Procedia PDF Downloads 642631 Improving the Global Competitiveness of SMEs by Logistics Transportation Management: Case Study Chicken Meat Supply Chain
Authors: P. Vanichkobchinda
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The Logistics Transportation techniques, Open Vehicle Routing (OVR) is an approach toward transportation cost reduction, especially for long distance pickup and delivery nodes. The outstanding characteristic of OVR is that the route starting node and ending node are not necessary the same as in typical vehicle routing problems. This advantage enables the routing to flow continuously and the vehicle does not always return to its home base. This research aims to develop a heuristic for the open vehicle routing problem with pickup and delivery under time window and loading capacity constraints to minimize the total distance. The proposed heuristic is developed based on the Insertion method, which is a simple method and suitable for the rapid calculation that allows insertion of the new additional transportation requirements along the original paths. According to the heuristic analysis, cost comparisons between the proposed heuristic and companies are using method, nearest neighbor method show that the insertion heuristic. Moreover, the proposed heuristic gave superior solutions in all types of test problems. In conclusion, the proposed heuristic can effectively and efficiently solve the open vehicle routing. The research indicates that the improvement of new transport's calculation and the open vehicle routing with "Insertion Heuristic" represent a better outcome with 34.3 percent in average. in cost savings. Moreover, the proposed heuristic gave superior solutions in all types of test problems. In conclusion, the proposed heuristic can effectively and efficiently solve the open vehicle routing.Keywords: business competitiveness, cost reduction, SMEs, logistics transportation, VRP
Procedia PDF Downloads 6872630 Evaluation of Living Mulches Effectiveness in Weed Suppression, and Seed Yield of Black cumin (Nigella sativa L.) Under Salt Stress
Authors: Fatemeh Benakashani, Hossein Tavakoli, Elias Soltani
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To ensure the sustainability of crop cultivation and rural economies, it is imperative that we focus on cultivating resilient crops capable of withstanding salt stress. However, the effective management of weeds in salt-affected soils remains a significant challenge. This study investigates the impact of living mulches, specifically Berseem clover (Trifolium alexandrinum) and Barley (Hordeum vulgare), on weed control, as well as the quality and yield of Black cumin (Nigella sativa) in salt-affected soil. In our research, we employed a two-fold mowing strategy for the living mulches: once following crop establishment and once before the flowering stage. Notably, the weed-free plots demonstrated Black cumin's seed yield, and oil content (31.1% to 34.3%), consistent with previous studies, highlighting its potential for the reclamation and utilization of salt-affected lands. However, Black cumin exhibited limited competitiveness against prevalent weeds in the field, such as Amaranthus retroflexus, Chenopodium album, and Portulaca oleracea, which significantly diminished both the 1000 grain mass in plots where weeds were present. Interestingly, the introduction of living mulches led to improvements in seed yield and seed oil content when compared to both weed-free and weed-infested plots. Notably, Berseem clover exhibited greater biomass than Barley, indicating its heightened competitiveness against weeds. Nevertheless, it's worth noting that in the long term, Berseem clover also competed with the main crop, thereby limiting overall productivity. Consequently, we recommend relocating the Berseem clover living mulch following the establishment of Black cumin as a strategy for weed management in Black cumin fields situated in salt-affected soils.Keywords: weed management, competition, clover, barley, medicinal plant
Procedia PDF Downloads 682629 A Microsurgery-Specific End-Effector Equipped with a Bipolar Surgical Tool and Haptic Feedback
Authors: Hamidreza Hoshyarmanesh, Sanju Lama, Garnette R. Sutherland
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In tele-operative robotic surgery, an ideal haptic device should be equipped with an intuitive and smooth end-effector to cover the surgeon’s hand/wrist degrees of freedom (DOF) and translate the hand joint motions to the end-effector of the remote manipulator with low effort and high level of comfort. This research introduces the design and development of a microsurgery-specific end-effector, a gimbal mechanism possessing 4 passive and 1 active DOFs, equipped with a bipolar forceps and haptic feedback. The robust gimbal structure is comprised of three light-weight links/joint, pitch, yaw, and roll, each consisting of low-friction support and a 2-channel accurate optical position sensor. The third link, which provides the tool roll, was specifically designed to grip the tool prongs and accommodate a low mass geared actuator together with a miniaturized capstan-rope mechanism. The actuator is able to generate delicate torques, using a threaded cylindrical capstan, to emulate the sense of pinch/coagulation during conventional microsurgery. While the tool left prong is fixed to the rolling link, the right prong bears a miniaturized drum sector with a large diameter to expand the force scale and resolution. The drum transmits the actuator output torque to the right prong and generates haptic force feedback at the tool level. The tool is also equipped with a hall-effect sensor and magnet bar installed vis-à-vis on the inner side of the two prongs to measure the tooltip distance and provide an analogue signal to the control system. We believe that such a haptic end-effector could significantly increase the accuracy of telerobotic surgery and help avoid high forces that are known to cause bleeding/injury.Keywords: end-effector, force generation, haptic interface, robotic surgery, surgical tool, tele-operation
Procedia PDF Downloads 1232628 Study on the Spatial Vitality of Waterfront Rail Transit Station Area: A Case Study of Main Urban Area in Chongqing
Authors: Lianxue Shi
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Urban waterfront rail transit stations exert a dual impact on both the waterfront and the transit station, resulting in a concentration of development elements in the surrounding space. In order to more effectively develop the space around the station, this study focuses on the perspective of the integration of station, city, and people. Taking Chongqing as an example, based on the Arc GIS platform, it explores the vitality of the site from the three dimensions of crowd activity heat, space facilities heat, and spatial accessibility. It conducts a comprehensive evaluation and interpretation of the vitality surrounding the waterfront rail transit station area in Chongqing. The study found that (1) the spatial vitality in the vicinity of waterfront rail transit stations is correlated with the waterfront's functional zoning and the intensity of development. Stations situated in waterfront residential and public spaces are more likely to experience a convergence of people, whereas those located in waterfront industrial areas exhibit lower levels of vitality. (2) Effective transportation accessibility plays a pivotal role in maintaining a steady flow of passengers and facilitating their movement. However, the three-dimensionality of urban space in mountainous regions is a notable challenge, leading to some stations experiencing limited accessibility. This underscores the importance of enhancing the optimization of walking space, particularly the access routes from the station to the waterfront area. (3) The density of spatial facilities around waterfront stations in old urban areas lags behind the population's needs, indicating a need to strengthen the allocation of relevant land and resources in these areas.Keywords: rail transit station, waterfront, influence area, spatial vitality, urban vitality
Procedia PDF Downloads 332627 Factors Affecting the Uptake of Modern Contraception Services in Oyo State, Nigeria
Authors: Folajinmi Oluwasina, Magbagbeola Dairo, Ikeoluwapo Ajayi
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Contraception has proven to be an effective way of controlling fertility and spacing births. Studies have shown that contraception can avert the high-risk pregnancies and consequently reduce maternal deaths up to 32%. Uptake of modern contraception is promoted as a mechanism to address the reproductive health needs of men and women, as well as the crucial challenge of rapid population increase. A cross- sectional descriptive study using a two- stage systematic sampling technique was used to select 530 women of reproductive age out of 20,000 households. Respondents were interviewed using a semi-structured questionnaire. Knowledge was assessed on a 5 point score in which a score of ≤ 2 rated poor while perception was scored on 36 points score in which a score of ≤ 18 was rated low. Data were analyzed using descriptive statistics, Chi-square test and logistic regression at p< 0.05. There were 530 respondents. Age of respondents was 30.3 ±7.8 years, and 73.0% were married. About 90% had good knowledge of contraception while 60.8% had used contraceptives. The commonest source of information about contraception was mass media (72.8%). Minority (26.1%) obtained husbands approval before using contraceptive while 20.0% had used modern contraceptives before the first birth. Many (54.5%) of the respondents agreed that contraception helps in improving standard of living and 64.7% had good perception about contraception. Factors that hindered effective uptake of contraception services included poor service provider’s attitude (33.3%) and congestion at the service centers (4.5%). Respondents with nonuse of contraceptive before first birth are less likely to subsequently use contraceptives (OR= 0.324, 95% CI= 0.1-0.5). Husband approval of contraceptives use was the major determinant of women’s contraceptive use (OR = 3.4, 95% CI = 1.3-8.7). Respondents who had family planning centers not more than 5 kilometers walking distance to their residence did not significantly use contraception services (41.5%) more than 21.1% of those who had to take means of transportation to the service venues. This study showed that majority of the respondents were knowledgeable and aware of contraception services, but husband’s agreement on the use of modern contraceptives remains poor. Programmes that enhances husbands approval of modern contraception is thus recommended.Keywords: contraception services, service provider’s attitude, uptake, husbands approval
Procedia PDF Downloads 3672626 Use of Non-woven Polyethylene Terephthalate Fabrics to Improve Certain Properties of Concrete
Authors: Sifatullah Bahij, Safiullah Omary, Francoise Feugeas, Amanullah Faqiri
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Plastic packages have been broadly used for a long time. Such widespread usage of plastic has resulted in an increased amount of plastic wastes and many environmental impacts. Plastic wastes are one of the most significant types of waste materials because of their non-degradation and low biodegradability. It is why many researchers tried to find a safe and environmentally friendly solution for plastic wastes. In this goal, in the civil engineering industry, many types of plastic wastes have been incorporated, as a partial substitution of aggregates or as additive materials (fibers) in concrete mixtures because of their lengthier lifetime and lower weight. This work aims to study the mechanical properties (compressive, split tensile and flexural strengths) of concrete with a water-cement ratio (w/c) of 0.45 and with the incorporation of non-woven PET plastic sheets. Five configurations -without PET (reference), 1-layer sheet, 2-side, 3-side, and full sample wrapping- were applied. The 7, 14 and 28-days samples’ compressive strengths, flexural strength and split tensile strength were measured. The outcomes of the study show that the compressive strength was improved for the wrapped samples, particularly for the cylindrical specimens. Also, split tensile and flexural behaviors of the wrapped samples improved significantly compared to the reference ones. Moreover, reference samples were damaged into many parts after mechanical testing, while wrapped specimens were taken by the applied configurations and were not divided into many small fragments. Therefore, non-woven fabrics appeared to improve some properties of the concrete.Keywords: solid waste plastic, non-woven polyethylene terephthalate sheets, mechanical behaviors, crack pattern
Procedia PDF Downloads 1312625 Utilization of Torula Yeast (Zymomonas mobilis) as Main/Reciprocal for Degradation of Municipal Organic Waste as Feed for Goats
Authors: Nkutere Chikezie Kanu, Nnamdi M. Anigbogu, Johnson C. Ezike
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The study was carried out to investigate the performance of Red Sokoto goats fed Municipal Oranic Wastes (MOW) subjected to two methods of in vivo degradation by Torula Yeast and Zymomonas mobilis. Two combination, Torula Yeast + Zymomonas mobilis (main degradation), and Zymomonas mobilis + Torula Yeast (Reciprocal degradation) were used to degrade MOW. Eighteen Red Sokoto goats of both sexes (9 males and 9 females) of ages between 6-8 were used for the study. The goats were randomly assigned into 3 treatments groups A, B and C respectively with 6 goats per treatment. The experiment was laid in a Completely Randomized Design and replicated 3 times. Treatment A groups were fed 30% Undegraded MOW base diet +concentrate mixture, Treatment B groups were fed 30% Main degraded MOW base diet +concentrate mixture, Treatment C groups were fed 30% Reciprocal degraded MOW base diet +concentrate mixture. The result of the daily weight gain was significantly (P<0.05) better than on the other Treatments. There was significant improvement (P<0.05) on the daily feed consumption in Treatment B than on the Treatments A and C. The feed conversion ratio revealed no significant (P>0.05) differences among the treatment groups but much better in the treatment B and C, the cost of feed consumed was much higher (P>0.05) in Treatment B followed by Treatment C, while Treatment A had the lowest. The cost/ kg weight gain that was recorded in Treatment A was better (P<0.05) than the Treatment B, followed by Treatment C, while the cost of production was high (P<0.05) in Treatment B than in other treatments. The gross profit was observed best (P<0.05) on the Treatment B, followed by Treatment C while Treatment A had the lowest. The net profit as noted in this study was much better (P<0.05) in Treatment B, and Treatment C, while the least was observed in Treatment A, where the return on investment was high in Treatments B and C, while Treatment A had the lowest.Keywords: reciprocal, torula yeast, Zymomonas mobilis, organic waste
Procedia PDF Downloads 2972624 Investigating The Effect Of Convection On The Rating Of Buried Cables Using The Finite Element Method
Authors: Sandy J. M. Balla, Jerry J. Walker, Isaac K. Kyere
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The heat transfer coefficient at the soil–air interface is important in calculating underground cable ampacity when convection occurs. Calculating the heat transfer coefficient accurately is complex because of the temperature variations at the earth's surface. This paper presents the effect of convection heat flow across the ground surface on the rating of three single-core, 132kV, XLPE cables buried underground. The Finite element method (FEM) is a numerical analysis technique used to determine the cable rating of buried cables under installation conditions that are difficult to support when using the analytical method. This study demonstrates the use of FEM to investigate the effect of convection on the rating ofburied cables in flat formation using QuickField finite element simulation software. As a result, developing a model to simulate this type of situation necessitates important considerations such as the following boundary conditions: burial depth, soil thermal resistivity, and soil temperature, which play an important role in the simulation's accuracy and reliability. The results show that when the ground surface is taken as a convection interface, the conductor temperature rises and may exceed the maximum permissible temperature when rated current flows. This is because the ground surface acts as a convection interface between the soil and the air (fluid). This result correlates and is compared with the rating obtained using the IEC60287 analytical method, which is based on the condition that the ground surface is an isotherm.Keywords: finite element method, convection, buried cables, steady-state rating
Procedia PDF Downloads 1322623 Entry, Descent and Landing System Design and Analysis of a Small Platform in Mars Environment
Authors: Daniele Calvi, Loris Franchi, Sabrina Corpino
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Thanks to the latest Mars mission, the planetary exploration has made enormous strides over the past ten years increasing the interest of the scientific community and beyond. These missions aim to fulfill many complex operations which are of paramount importance to mission success. Among these, a special mention goes to the Entry, Descent and Landing (EDL) functions which require a dedicated system to overcome all the obstacles of these critical phases. The general objective of the system is to safely bring the spacecraft from orbital conditions to rest on the planet surface, following the designed mission profile. For this reason, this work aims to develop a simulation tool integrating the re-entry trajectory algorithm in order to support the EDL design during the preliminary phase of the mission. This tool was used on a reference unmanned mission, whose objective is finding bio-evidence and bio-hazards on Martian (sub)surface in order to support the future manned mission. Regarding the concept of operations (CONOPS) of the mission, it concerns the use of Space Penetrator Systems (SPS) that will descend on Mars surface following a ballistic fall and will penetrate the ground after the impact with the surface (around 50 and 300 cm of depth). Each SPS shall contain all the instrumentation required to sample and make the required analyses. Respecting the low-cost and low-mass requirements, as result of the tool, an Entry Descent and Impact (EDI) system based on inflatable structure has been designed. Hence, a solution could be the one chosen by Finnish Meteorological Institute in the Mars Met-Net mission, using an inflatable Thermal Protection System (TPS) called Inflatable Braking Unit (IBU) and an additional inflatable decelerator. Consequently, there are three configurations during the EDI: at altitude of 125 km the IBU is inflated at speed 5.5 km/s; at altitude of 16 km the IBU is jettisoned and an Additional Inflatable Braking Unit (AIBU) is inflated; Lastly at about 13 km, the SPS is ejected from AIBU and it impacts on the Martian surface. Since all parameters are evaluated, it is possible to confirm that the chosen EDI system and strategy verify the requirements of the mission.Keywords: EDL, Mars, mission, SPS, TPS
Procedia PDF Downloads 170