Search results for: solution of linear algebraic equations
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9757

Search results for: solution of linear algebraic equations

4507 Microdosimetry in Biological Cells: A Monte Carlo Method

Authors: Hamidreza Jabal Ameli, Anahita Movahedi

Abstract:

Purpose: In radionuclide therapy, radioactive atoms are coupled to monoclonal antibodies (mAbs) for treating cancer tumor while limiting radiation to healthy tissues. We know that tumoral and normal tissues are not equally sensitive to radiation. In fact, biological effects such as cellular repair processes or the presence of less radiosensitive cells such as hypoxic cells should be taken account. For this reason, in this paper, we want to calculate biological effect dose (BED) inside tumoral area and healthy cells around tumors. Methods: In this study, deposited doses of a radionuclide, gold-198, inside cells lattice and surrounding healthy tissues were calculated with Monte Carlo method. The elemental compositions and density of malignant and healthy tissues were obtained from ICRU Report 44. For reaching to real condition of oxygen effects, the necrosis and hypoxia area inside tumors has been assessed. Results: With regard to linear-quadratic expression which was defined in Monte Carlo, results showed that a large amount of BED is deposited in the well-oxygenated part of the hypoxia area compared to necrosis area. Moreover, there is a significant difference between the curves of absorbed dose with BED and without BED.

Keywords: biological dose, monte carlo, hypoxia, radionuclide therapy

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4506 A Comparison of Biosorption of Radionuclides Tl-201 on Different Biosorbents and Their Empirical Modelling

Authors: Sinan Yapici, Hayrettin Eroglu

Abstract:

The discharge of the aqueous radionuclides wastes used for the diagnoses of diseases and treatments of patients in nuclear medicine can cause fatal health problems when the radionuclides and its stable daughter component mix with underground water. Tl-201, which is one of the radionuclides commonly used in the nuclear medicine, is a toxic substance and is converted to its stable daughter component Hg-201, which is also a poisonous heavy metal: Tl201 → Hg201 + Gamma Ray [135-167 Kev (12%)] + X Ray [69-83 Kev (88%)]; t1/2 = 73,1 h. The purpose of the present work was to remove Tl-201 radionuclides from aqueous solution by biosorption on the solid bio wastes of food and cosmetic industry as bio sorbents of prina from an olive oil plant, rose residue from a rose oil plant and tea residue from a tea plant, and to make a comparison of the biosorption efficiencies. The effects of the biosorption temperature, initial pH of the aqueous solution, bio sorbent dose, particle size and stirring speed on the biosorption yield were investigated in a batch process. It was observed that the biosorption is a rapid process with an equilibrium time less than 10 minutes for all the bio sorbents. The efficiencies were found to be close to each other and measured maximum efficiencies were 93,30 percent for rose residue, 94,1 for prina and 98,4 for tea residue. In a temperature range of 283 and 313 K, the adsorption decreased with increasing temperature almost in a similar way. In a pH range of 2-10, increasing pH enhanced biosorption efficiency up to pH=7 and then the efficiency remained constant in a similar path for all the biosorbents. Increasing stirring speed from 360 to 720 rpm enhanced slightly the biosorption efficiency almost at the same ratio for all bio sorbents. Increasing particle size decreased the efficiency for all biosorbent; however the most negatively effected biosorbent was prina with a decrease in biosorption efficiency from about 84 percent to 40 with an increase in the nominal particle size 0,181 mm to 1,05 while the least effected one, tea residue, went down from about 97 percent to 87,5. The biosorption efficiencies of all the bio sorbents increased with increasing biosorbent dose in the range of 1,5 to 15,0 g/L in a similar manner. The fit of the experimental results to the adsorption isotherms proved that the biosorption process for all the bio sorbents can be represented best by Freundlich model. The kinetic analysis showed that all the processes fit very well to pseudo second order rate model. The thermodynamics calculations gave ∆G values between -8636 J mol-1 and -5378 for tea residue, -5313 and -3343 for rose residue, and -5701 and -3642 for prina with a ∆H values of -39516 J mol-1, -23660 and -26190, and ∆S values of -108.8 J mol-1 K-1, -64,0, -72,0 respectively, showing spontaneous and exothermic character of the processes. An empirical biosorption model in the following form was derived for each biosorbent as function of the parameters and time, taking into account the form of kinetic model, with regression coefficients over 0.9990 where At is biosorbtion efficiency at any time and Ae is the equilibrium efficiency, t is adsorption period as s, ko a constant, pH the initial acidity of biosorption medium, w the stirring speed as s-1, S the biosorbent dose as g L-1, D the particle size as m, and a, b, c, and e are the powers of the parameters, respectively, E a constant containing activation energy and T the temperature as K.

Keywords: radiation, diosorption, thallium, empirical modelling

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4505 Evaluation of Oral Biofilm Suppression by Carribean Herbal Extracts

Authors: Ravi Teja Chitturi Suryaprakash, Chandrashekhar Unakal, Haytham Al-Bayaty, Duraisamy Saravanakumar

Abstract:

Background and significance: Oral biofilm formation is a well-known causative factor for caries and periodontal diseases. Scientists over the years have been trying to find a solution against the formation of oral biofilms. Though several advances have been made to understand the microbial ecology and how the bio film survives, it is still an enigma to researchers to find a chemical product that not only can inhibit the formation of oral bio film but also not disturb the oral micro flora required for oral health and not to cause damage to the cells of the oral cavity. One such product that has never been investigated much are herbal preparations. Some of the microorganisms important in the formation of biofilm are Streptococcus mutans, Actinomyces naeslundi, Streptococuss oralis and Prevotella intermedia. The aim of this study was to study the antimicrobial property of some herbal extracts available in Trinidad and Tobago against these pathogens. The significance of this study is that identification of biologically effective plant extracts can result in indigenous development of mouth rinses and tooth pastes that the people can benefit from to not only develop effective but also a cheap solution. Methodology: The extracts from the leaves of Plectranthus ambonicus, Ocmium tenuiflorum, Azadirchata indica, Anacardium occidentale, Psidium guajava were prepared by dissolving them in water. The extracts from the roots of Curcuma longa were prepared similarly and the antimicrobial activity of these six plant extracts was determined by the agar well diffusion method using minimum inhibitory concentration (MIC) against Streptococcus mutans, Actinomyces naeslundi, Streptococuss oralis and Prevotella intermedia and compared with chlorhexidine. Results: The six plant extracts showed variable effect on the oral micro-organisms. Ocmium tenuiflorum (16.66 ± 0.44, 14 ± 0.58, 13.33 ± 0.88, 12.83 ± 0.60), Azadirchata indica (17.5 ± 0.28, 14.83 ± 0.17, 15 ± 0.58, 12.83 ± 0.6) and Curcuma longa (16.16 ± 0.44, 13.66 ± 0.88, 12.33 ± 0.88, 11.33 ± 0.67) were found to have highest inhibitory activity against all the four pathogens (Streptococcus mutans, Streptococuss oralis, Actinomyces naeslundi, and Prevotella intermedia) respectively. Conclusion: Although the extracts were not pure compounds we obtained antimicrobial results which determine that they are potent antimicrobial agents. Further derivation of pure compounds from these extracts could be lucrative as it might lead to the development of a cost effective and biologically safe medicine to act against oral biofilms. Acknowledgement: The authors would like to acknowledge the Campus Research and Publication Fund Committee, The University of the West Indies for funding this study and would also like to acknowledge Dr. Leonette Cox, Department of Chemistry, Faculty of Science and Technology, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago for helping to prepare the plant extracts.

Keywords: agar well diffusion method, herbal extracts, minimum inhibitory concentration, oral biofilm forming microorganisms

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4504 Numerical investigation of Hydrodynamic and Parietal Heat Transfer to Bingham Fluid Agitated in a Vessel by Helical Ribbon Impeller

Authors: Mounir Baccar, Amel Gammoudi, Abdelhak Ayadi

Abstract:

The efficient mixing of highly viscous fluids is required for many industries such as food, polymers or paints production. The homogeneity is a challenging operation for this fluids type since they operate at low Reynolds number to reduce the required power of the used impellers. Particularly, close-clearance impellers, mainly helical ribbons, are chosen for highly viscous fluids agitated in laminar regime which is currently heated through vessel wall. Indeed, they are characterized by high shear strains closer to the vessel wall, which causes a disturbing thermal boundary layer and ensures the homogenization of the bulk volume by axial and radial vortices. The hydrodynamic and thermal behaviors of Newtonian fluids in vessels agitated by helical ribbon impellers, has been mostly studied by many researchers. However, rarely researchers investigated numerically the agitation of yield stress fluid by means of helical ribbon impellers. This paper aims to study the effect of the Double Helical Ribbon (DHR) stirrers on both the hydrodynamic and the thermal behaviors of yield stress fluids treated in a cylindrical vessel by means of numerical simulation approach. For this purpose, continuity, momentum, and thermal equations were solved by means of 3D finite volume technique. The effect of Oldroyd (Od) and Reynolds (Re) numbers on the power (Po) and Nusselt (Nu) numbers for the mentioned stirrer type have been studied. Also, the velocity and thermal fields, the dissipation function and the apparent viscosity have been presented in different (r-z) and (r-θ) planes.

Keywords: Bingham fluid, Hydrodynamic and thermal behavior, helical ribbon, mixing, numerical modelling

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4503 Experimental Study on Use of Crumb Rubber to Mitigate Expansive Soil Pressures on Basement Walls

Authors: Kwestan Salimi, Jenna Jacoby, Michelle Basham, Amy Cerato

Abstract:

The extreme annual weather patterns of the central United States have increased the need for underground shelters for protection from destructive tornadic activity. However, very few residential homes have basements due to the added construction expense and the prevalence of expansive soils covering the central portion of the United States. These expansive soils shrink and swell, increasing earth pressure on basement walls. To mitigate the effect of expansive soils on basement walls, this study performed bench-scale tests using a common natural expansive soil mitigated with a backfill layer of crumb rubber. The results revealed that at 80% soil compaction, a 1:6 backfill height to total height ratio produced a 66% reduction in swell pressure. However, this percent reduction decreased to 27% for 90% soil compaction. It was also found that there is a strong linear correlation between compaction percentage and reduction in swell pressure when using the same backfill height to total height ratio. Using this correlation and extrapolating to 95% compaction, the percent reduction in swell pressure was approximately 12%.

Keywords: expansive soils, swell/shrink, swell pressure, stabilization, crumb rubber

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4502 Experimental Study on Stabilisation of a Soft Soil by Alkaline Activation of Industrial By-Products

Authors: Mohammadjavad Yaghoubi, Arul Arulrajah, Mahdi M. Disfani, Suksun Horpibulsuk, Myint W. Bo, Stephen P. Darmawan

Abstract:

Utilising waste materials, such as fly ash (FA) and slag (S) stockpiled in landfills, has drawn the attention of researchers and engineers in the recent years. There is a great potential for usage of these wastes in ground improvement projects, especially where deep deposits of soft compressible soils exist. This paper investigates the changes in the strength development of a high water content soft soil stabilised with alkaline activated FA and S, termed as geopolymer binder, to use in deep soil mixing technology. The strength improvement and the changes in the microstructure of the mixtures have been studied. The results show that using FA and S-based geopolymers can increases the strength significantly. Furthermore, utilising FA and S in ground improvement projects, where large amounts of binders are required, can be a solution to the disposal of these wastes.

Keywords: alkaline activation, fly ash, geopolymer, slag, strength development

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4501 Analytical Formulae for Parameters Involved in Side Slopes of Embankments Stability

Authors: Abdulrahman Abdulrahman, Abir Abdulrahman

Abstract:

The stability of slopes of earthen embankments is usually examined by Swedish slip circle method or the slices method. The factor of safety against sliding using Fellenius procedure depends upon the angle formed by the arc of sliding at the center ψ and the radius of the slip circle r. The values of both mentioned parameters ψ and r aren't precisely predicted because they are measured from the drawing. In this paper, analytical formulae were derived for finding the exact values of both ψ and r. Also this paper presents the different conditions of intersections the slip circle with the body of an earthen dam and the coordinate of intersection points. Numerical examples are chosen for demonstration the proposed solution

Keywords: earthen dams stability, , earthen embankments stability, , Fellenius method, hydraulic structures, , side slopes stability, , slices method, Swedish slip circle

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4500 Regression Analysis in Estimating Stream-Flow and the Effect of Hierarchical Clustering Analysis: A Case Study in Euphrates-Tigris Basin

Authors: Goksel Ezgi Guzey, Bihrat Onoz

Abstract:

The scarcity of streamflow gauging stations and the increasing effects of global warming cause designing water management systems to be very difficult. This study is a significant contribution to assessing regional regression models for estimating streamflow. In this study, simulated meteorological data was related to the observed streamflow data from 1971 to 2020 for 33 stream gauging stations of the Euphrates-Tigris Basin. Ordinary least squares regression was used to predict flow for 2020-2100 with the simulated meteorological data. CORDEX- EURO and CORDEX-MENA domains were used with 0.11 and 0.22 grids, respectively, to estimate climate conditions under certain climate scenarios. Twelve meteorological variables simulated by two regional climate models, RCA4 and RegCM4, were used as independent variables in the ordinary least squares regression, where the observed streamflow was the dependent variable. The variability of streamflow was then calculated with 5-6 meteorological variables and watershed characteristics such as area and height prior to the application. Of the regression analysis of 31 stream gauging stations' data, the stations were subjected to a clustering analysis, which grouped the stations in two clusters in terms of their hydrometeorological properties. Two streamflow equations were found for the two clusters of stream gauging stations for every domain and every regional climate model, which increased the efficiency of streamflow estimation by a range of 10-15% for all the models. This study underlines the importance of homogeneity of a region in estimating streamflow not only in terms of the geographical location but also in terms of the meteorological characteristics of that region.

Keywords: hydrology, streamflow estimation, climate change, hydrologic modeling, HBV, hydropower

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4499 Development and Testing of an Instrument to Measure Beliefs about Cervical Cancer Screening among Women in Botswana

Authors: Ditsapelo M. McFarland

Abstract:

Background: Despite the availability of the Pap smear services in urban areas in Botswana, most women in such areas do not seem to screen regular for prevention of the cervical cancer disease. Reasons for non-use of the available Pap smear services are not well understood. Beliefs about cancer may influence participation in cancer screening in these women. The purpose of this study was to develop an instrument to measure beliefs about cervical cancer and Pap smear screening among Black women in Botswana, and evaluate the psychometric properties of the instrument. Significance: Instruments that are designed to measure beliefs about cervical cancer and screening among black women in Botswana, as well as in the surrounding region, are presently not available. Valid and reliable instruments are needed for exploration of the women’s beliefs about cervical cancer. Conceptual Framework: The Health Belief Model (HBM) provided a conceptual framework for the study. Methodology: The study was done in four phases: Phase 1: item generation: 15 items were generated from literature review and qualitative data for each of four conceptually defined HBM constructs: Perceived susceptibility, severity, benefits, and barriers (Version 1). Phase 2: content validity: Four experts who were advanced practice nurses of African descent and were familiar with the content and the HBM evaluated the content. Experts rated the items on a 4-point Likert scale ranging from: 1=not relevant, 2=somewhat relevant, 3=relevant and 4=very relevant. Fifty-five items were retained for instrument development: perceived susceptibility - 11, severity - 14, benefits - 15 and barriers - 15, all measuring on a 4-point Likert scale ranging from strongly disagree (1) to strongly agree (4). (Version 2). Phase 3: pilot testing: The instrument was pilot tested on a convenient sample of 30 women in Botswana and revised as needed. Phase 4: reliability: the revised instrument (Version 3) was submitted to a larger sample of women in Botswana (n=300) for reliability testing. The sample included women who were Batswana by birth and decent, were aged 30 years and above and could complete an English questionnaire. Data were collected with the assistance of trained research assistants. Major findings: confirmatory factor analysis of the 55 items found that a number of items did not adequately load in a four-factor solution. Items that exhibited reasonable reliability and had low frequency of missing values (n=36) were retained: perceived barriers (14 items), perceived benefits (8 items), perceived severity (4 items), and perceived susceptibility (10 items). confirmatory factor analysis (principle components) for a four factor solution using varimax rotation demonstrated that these four factors explained 43% of the variation in these 36 items. Conclusion: reliability analysis using Cronbach’s Alpha gave generally satisfactory results with values from 0.53 to 0.89.

Keywords: cervical cancer, factor analysis, psychometric evaluation, varimax rotation

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4498 Governance Framework for an Emerging Trust Ecosystem with a Blockchain-Based Supply Chain

Authors: Ismael Ávila, José Reynaldo F. Filho, Vasco Varanda Picchi

Abstract:

The ever-growing consumer awareness of food provenance in Brazil is driving the creation of a trusted ecosystem around the animal protein supply chain. The traceability and accountability requirements of such an ecosystem demand a blockchain layer to strengthen the weak links in that chain. For that, direct involvement of the companies in the blockchain transactions, including as validator nodes of the network, implies formalizing a partnership with the consortium behind the ecosystem. Yet, their compliance standards usually require that a formal governance structure is in place before they agree with any membership terms. In light of such a strategic role of blockchain governance, the paper discusses a framework for tailoring a governance model for a blockchain-based solution aimed at the meat supply chain and evaluates principles and attributes in terms of their relevance to the development of a robust trust ecosystem.

Keywords: blockchain, governance, trust ecosystem, supply chain, traceability

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4497 A Case Study of Bee Algorithm for Ready Mixed Concrete Problem

Authors: Wuthichai Wongthatsanekorn, Nuntana Matheekrieangkrai

Abstract:

This research proposes Bee Algorithm (BA) to optimize Ready Mixed Concrete (RMC) truck scheduling problem from single batch plant to multiple construction sites. This problem is considered as an NP-hard constrained combinatorial optimization problem. This paper provides the details of the RMC dispatching process and its related constraints. BA was then developed to minimize total waiting time of RMC trucks while satisfying all constraints. The performance of BA is then evaluated on two benchmark problems (3 and 5construction sites) according to previous researchers. The simulation results of BA are compared in term of efficiency and accuracy with Genetic Algorithm (GA) and all problems show that BA approach outperforms GA in term of efficiency and accuracy to obtain optimal solution. Hence, BA approach could be practically implemented to obtain the best schedule.

Keywords: bee colony optimization, ready mixed concrete problem, ruck scheduling, multiple construction sites

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4496 A Hybrid Data Mining Algorithm Based System for Intelligent Defence Mission Readiness and Maintenance Scheduling

Authors: Shivam Dwivedi, Sumit Prakash Gupta, Durga Toshniwal

Abstract:

It is a challenging task in today’s date to keep defence forces in the highest state of combat readiness with budgetary constraints. A huge amount of time and money is squandered in the unnecessary and expensive traditional maintenance activities. To overcome this limitation Defence Intelligent Mission Readiness and Maintenance Scheduling System has been proposed, which ameliorates the maintenance system by diagnosing the condition and predicting the maintenance requirements. Based on new data mining algorithms, this system intelligently optimises mission readiness for imminent operations and maintenance scheduling in repair echelons. With modified data mining algorithms such as Weighted Feature Ranking Genetic Algorithm and SVM-Random Forest Linear ensemble, it improves the reliability, availability and safety, alongside reducing maintenance cost and Equipment Out of Action (EOA) time. The results clearly conclude that the introduced algorithms have an edge over the conventional data mining algorithms. The system utilizing the intelligent condition-based maintenance approach improves the operational and maintenance decision strategy of the defence force.

Keywords: condition based maintenance, data mining, defence maintenance, ensemble, genetic algorithms, maintenance scheduling, mission capability

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4495 Regeneration of Cesium-Exhausted Activated Carbons by Microwave Irradiation

Authors: Pietro P. Falciglia, Erica Gagliano, Vincenza Brancato, Alfio Catalfo, Guglielmo Finocchiaro, Guido De Guidi, Stefano Romano, Paolo Roccaro, Federico G. A. Vagliasindi

Abstract:

Cesium-137 (¹³⁷Cs) is a major radionuclide in spent nuclear fuel processing, and it represents the most important cause of contamination related to nuclear accidents. Cesium-137 has long-term radiological effects representing a major concern for the human health. Several physico-chemical methods have been proposed for ¹³⁷Cs removal from impacted water: ion-exchange, adsorption, chemical precipitation, membrane process, coagulation, and electrochemical. However, these methods can be limited by ionic selectivity and efficiency, or they present very restricted full-scale application due to equipment and chemical high costs. On the other hand, adsorption is considered a more cost-effective solution, and activated carbons (ACs) are known as a low-cost and effective adsorbent for a wide range of pollutants among which radionuclides. However, adsorption of Cs onto ACs has been investigated in very few and not exhaustive studies. In addition, exhausted activated carbons are generally discarded in landfill, that is not an eco-friendly and economic solution. Consequently, the regeneration of exhausted ACs must be considered a preferable choice. Several alternatives, including conventional thermal-, solvent-, biological- and electrochemical-regeneration, are available but are affected by several economic or environmental concerns. Microwave (MW) irradiation has been widely used in industrial and environmental applications and it has attracted many attentions to regenerating activated carbons. The growing interest in MW irradiation is based on the passive ability of the irradiated medium to convert a low power irradiation energy into a rapid and large temperature increase if the media presents good dielectric features. ACs are excellent MW-absorbers, with a high mechanical strength and a good resistance towards heating process. This work investigates the feasibility of MW irradiation for the regeneration of Cs-exhausted ACs. Adsorption batch experiments were carried out using commercially available granular activated carbon (GAC), then Cs-saturated AC samples were treated using a controllable bench-scale 2.45-GHz MW oven and investigating different adsorption-regeneration cycles. The regeneration efficiency (RE), weight loss percentage, and textural properties of the AC samples during the adsorption-regeneration cycles were also assessed. Main results demonstrated a relatively low adsorption capacity for Cs, although the feasibility of ACs was strictly linked to their dielectric nature, which allows a very efficient thermal regeneration by MW irradiation. The weight loss percentage was found less than 2%, and an increase in RE after three cycles was also observed. Furthermore, MW regeneration preserved the pore structure of the regenerated ACs. For a deeper exploration of the full-scale applicability of MW regeneration, further investigations on more adsorption-regeneration cycles or using fixed-bed columns are required.

Keywords: adsorption mechanisms, cesium, granular activated carbons, microwave regeneration

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4494 Fermentable Sugars from Palm Empty Fruit Bunch Biomass for Bioethanol Production

Authors: U. A. Asli, H. Hamid, Z. A. Zakaria, A. N. Sadikin, R. Rasit

Abstract:

This study investigated the effect of a dilute acid, lime and ammonia aqueous pretreatment on the fermentable sugars conversion from empty fruit bunch (EFB) biomass. The dilute acid treatment was carried out in an autoclave, at 121ºC with 4 % of sulphuric acid. In the lime pretreatment, 3 wt % of calcium hydroxide was used, whereas the third method was done by soaking EFB with 28 % ammonia solution. Then the EFB biomass was subjected to a two-stage-acid hydrolysis process. Subsequently, the hydrolysate was fermented by using instant baker’s yeast to produce bioethanol. The highest glucose yield was 890 mg/g of biomass, obtained from the sample which underwent lime pretreatment. The highest bioethanol yield of 6.1mg/g of glucose was achieved from acid pretreatment. This showed that the acid pretreatment gave the most fermentable sugars compared to the other two pretreatments.

Keywords: bioethanol, biomass, empty fruit bunch (EFB), fermentable sugars

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4493 Effects of a Cooler on the Sampling Process in a Continuous Emission Monitoring System

Authors: J. W. Ahn, I. Y. Choi, T. V. Dinh, J. C. Kim

Abstract:

A cooler has been widely employed in the extractive system of the continuous emission monitoring system (CEMS) to remove water vapor in the gas stream. The effect of the cooler on analytical target gases was investigated in this research. A commercial cooler for the CEMS operated at 4 C was used. Several gases emitted from a coal power plant (i.e. CO2, SO2, NO, NO2 and CO) were mixed with humid air, and then introduced into the cooler to observe its effect. Concentrations of SO2, NO, NO2 and CO were made as 200 ppm. The CO2 concentration was 8%. The inlet absolute humidity was produced as 12.5% at 100 C using a bubbling method. It was found that the reduction rate of SO2 was the highest (~21%), followed by NO2 (~17%), CO2 (~11%) and CO (~10%). In contrast, the cooler was not affected by NO gas. The result indicated that the cooler caused a significant effect on the water soluble gases due to condensate water in the cooler. To overcome this problem, a correction factor may be applied. However, water vapor might be different, and emissions of target gases are also various. Therefore, the correction factor is not only a solution, but also a better available method should be employed.

Keywords: cooler, CEMS, monitoring, reproductive, sampling

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4492 Aircraft Landing Process Simulation Using Multi-Body Multi-Dynamics Software

Authors: Ahmad Kavousi, Ali Delaviz

Abstract:

In this project, the landing process is simulated by using of multi-body dynamics commercial software. Various factors, including landing situations, aircraft structures and climate are used in this simulation. The purpose of this project is to determine the forces exerted on the aircraft landing gears in landing process in various landing conditions. For this purpose, the ADAMS multi-body dynamics software is used. Different scenarios based on FAR-25, including level landing, tail-down landing, crab landing are simulated. Results of dynamic simulation software with landing load factor obtained from the analytical solution are compared. The effect of fuselage elasticity on the landing load is studied. For this purpose, both of elastic and rigid body assumptions are used in the simulation process, and the results are compared and some conclusions are made.

Keywords: landing gear, landing process, aircraft, multi-body dynamics

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4491 Transfer Knowledge From Multiple Source Problems to a Target Problem in Genetic Algorithm

Authors: Terence Soule, Tami Al Ghamdi

Abstract:

To study how to transfer knowledge from multiple source problems to the target problem, we modeled the Transfer Learning (TL) process using Genetic Algorithms as the model solver. TL is the process that aims to transfer learned data from one problem to another problem. The TL process aims to help Machine Learning (ML) algorithms find a solution to the problems. The Genetic Algorithms (GA) give researchers access to information that we have about how the old problem is solved. In this paper, we have five different source problems, and we transfer the knowledge to the target problem. We studied different scenarios of the target problem. The results showed combined knowledge from multiple source problems improves the GA performance. Also, the process of combining knowledge from several problems results in promoting diversity of the transferred population.

Keywords: transfer learning, genetic algorithm, evolutionary computation, source and target

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4490 Recommending Appropriate Type of Green Roof Considering Urban Typology and Climatic Zoning in Iran

Authors: Ghazal Raheb

Abstract:

Population growth in big cities of Iran has led to limitation of land resources, more consumption of non-renewable sources of energy and many environmental problems. Emerging of overbuilt urban areas and decreasing amount of green spaces cause the appearance of an undesirable landscape in the cities. Green roof technology is a solution to improve environmental concerns in urban areas which combines green spaces with buildings as the private or semi-private spaces. Successful implementation in different areas definitely depends on accommodation of green roof type with the environment and urban and building typology in Iran. This paper is aiming to provide some recommendation for selecting appropriate type of green roof and executive solutions considering to climatic zoning and urban situation in Iran. Two main aspects which have been considered are environmental and urban typology factors.

Keywords: green roof, urban typology, climate zone, landscape

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4489 Microfluidic Fluid Shear Mechanotransduction Device Using Linear Optimization of Hydraulic Channels

Authors: Sanat K. Dash, Rama S. Verma, Sarit K. Das

Abstract:

A logarithmic microfluidic shear device was designed and fabricated for cellular mechanotransduction studies. The device contains four cell culture chambers in which flow was modulated to achieve a logarithmic increment. Resistance values were optimized to make the device compact. The network of resistances was developed according to a unique combination of series and parallel resistances as found via optimization. Simulation results done in Ansys 16.1 matched the analytical calculations and showed the shear stress distribution at different inlet flow rates. Fabrication of the device was carried out using conventional photolithography and PDMS soft lithography. Flow profile was validated taking DI water as working fluid and measuring the volume collected at all four outlets. Volumes collected at the outlets were in accordance with the simulation results at inlet flow rates ranging from 1 ml/min to 0.1 ml/min. The device can exert fluid shear stresses ranging four orders of magnitude on the culture chamber walls which will cover shear stress values from interstitial flow to blood flow. This will allow studying cell behavior in the long physiological range of shear stress in a single run reducing number of experiments.

Keywords: microfluidics, mechanotransduction, fluid shear stress, physiological shear

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4488 A Study of Industry 4.0 and Digital Transformation

Authors: Ibrahim Bashir, Yahaya Y. Yusuf

Abstract:

The ongoing shift towards Industry 4.0 represents a critical growth factor in the industrial enterprise, where the digital transformation of industries is increasingly seen as a crucial element for competitiveness. This transformation holds substantial potential, yet its full benefits have yet to be realized due to the fragmented approach to introducing Industry 4.0 technologies. Therefore, this pilot study aims to explore the individual and collective impact of Industry 4.0 technologies and digital transformation on organizational performance. Data were collected through a questionnaire-based survey across 51 companies in the manufacturing industry in the United Kingdom. The correlations and multiple linear regression analyses were conducted to assess the relationship and impact between the variables in the study. The results show that Industry 4.0 and digital transformation positively influence organizational performance and that Industry 4.0 technologies positively influence digital transformation. The results of this pilot study indicate that the implementation of Industry 4.0 technology is vital for increasing organizational performance; however, their roles differ largely. The differences are manifest in how the types of Industry 4.0 technologies correlate with how organizations integrate digital technologies into their operations. Hence, there is a clear indication of a strong correlation between Industry 4.0 technology, digital transformation, and organizational performance. Consequently, our study presents numerous pertinent implications that propel the theory of I4.0, digital business transformation (DBT), and organizational performance forward, as well as guide managers in the manufacturing sector.

Keywords: industry 4.0 technologies, digital transformation, digital integration, organizational performance

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4487 Social Sustainability Quotient of Vertical Habitats

Authors: Abdullah Mohamed, Raipat Vaidehi

Abstract:

With increasing immigration to urban areas, every city is experiencing shortage of housing. Vertical habitats are the only solution to this problem, it is hence important to make sure that these habitats are environmentally, socially and economically sustainable. A lot of work on vertical habitats has already been carried out in terms of environmental and economic sustainability, hence this research aims to study the aspects of social sustainability of the vertical habitats. It being the least studied topic, opens many reals of novelty and uniqueness. In this Research, user perception survey and various mapping methods have been used to study the social sustainability of the existing vertical habitats in the selected cities. The various aspects that can be used to define social sustainability of any place include; safety, equity, accessibility, legibility, imagibility, readability, memorability and ease of movement. This research would help to evolve new strategies in form of design and/or guidelines to make the existing vertical habitats socially sustainable.

Keywords: user lifestyle, user perception, social sustainability, vertical habitats

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4486 Role of Osmoregulators for Enhancing Salinity Stress Tolerance in Chickpea

Authors: Mahmoud Ahmed Khater

Abstract:

This study aimed to improve the deleterious effects of salinity stress in chickpeas using both proline and glycine betaine as osmoregulants. The aim was achieved using foliar spraying with different concentrations of proline (5 mM and 10 mM) and glycinebetaine (10 mM and 20 mM) to chickpea plants grown in pots under salinity stress (3000 mg/l NaCl) at the greenhouse of the National Research Centre, Egypt, during two successive seasons 2021/2022 and 2022/2023. Results indicated that all applied treatments caused significant increases in most of the investigated parameters of chickpea plants irrigated with either tap water or saline solution relative to the corresponding control. It is worth mentioning that proline treatments were more effective than glycine betaine treatments in increasing the salinity tolerance of chickpea plants, reflected in their quality and quantity. Moreover, proline treatment at 5mM was the most pronounced treatment in alleviating the deleterious effect of salinity on chickpea plants.

Keywords: cicer arietinum L., osmoprotectant, proline, glycinebetaine salinity tolerance

Procedia PDF Downloads 29
4485 Improving Utilization of Sugarcane by Replacing Ordinary Propagation Material with Small Chips of Sugarcane Planted in Paper Pots

Authors: C. Garcia, C. Andreasen

Abstract:

Sugarcane is an important resource for bioenergy. Fields are usually established by using 15-20 cm pieces of sugarcane stalks as propagation material. An alternative method is to use small chips with nodes from sugarcane stalks. Plants from nodes are often established in plastic pots, but plastic pots could be replaced with biodegradable paper pots. This would be a more sustainable solution, reducing labor costs and avoiding pollution with plastic. We compared the establishment of plants from nodes taken from three different part of the sugarcane plant. The nodes were planted in plastic and paper pots. There was no significant difference between plants established in the two pot types. Nodes from different part of the stalk had different sprouting capacity. Nodes from the top parts sprouted significantly better than nodes taken from the middle or nodes taken closed to the ground in two experiments. Nodes with a length of 3 cm performed better than nodes with a length of 2 cm.

Keywords: nodes, paper pots, propagation material, sugarcane

Procedia PDF Downloads 199
4484 Compensation of Power Quality Disturbances Using DVR

Authors: R. Rezaeipour

Abstract:

One of the key aspects of power quality improvement in power system is the mitigation of voltage sags/swells and flicker. Custom power devices have been known as the best tools for voltage disturbances mitigation as well as reactive power compensation. Dynamic voltage restorer (DVR) which is the most efficient and effective modern custom power device can provide the most commercial solution to solve several problems of power quality in distribution networks. This paper deals with analysis and simulation technique of DVR based on instantaneous power theory which is a quick control to detect signals. The main purpose of this work is to remove three important disturbances including voltage sags/swells and flicker. Simulation of the proposed method was carried out on two sample systems by using MATLAB software environment and the results of simulation show that the proposed method is able to provide desirable power quality in the presence of wide range of disturbances.

Keywords: DVR, power quality, voltage sags, voltage swells, flicker

Procedia PDF Downloads 336
4483 Electrical Transport in Bi₁Sb₁Te₁.₅Se₁.₅ /α-RuCl₃ Heterostructure Nanodevices

Authors: Shoubhik Mandal, Debarghya Mallick, Abhishek Banerjee, R. Ganesan, P. S. Anil Kumar

Abstract:

We report magnetotransport measurements in Bi₁Sb₁Te₁.₅Se₁.₅/RuCl₃ heterostructure nanodevices. Bi₁Sb₁Te₁.₅Se₁.₅ (BSTS) is a strong three-dimensional topological insulator (3D-TI) that hosts conducting topological surface states (TSS) enclosing an insulating bulk. α-RuCl₃ (namely, RuCl₃) is an anti-ferromagnet that is predicted to behave as a Kitaev-like quantum spin liquid carrying Majorana excitations. Temperature (T)-dependent resistivity measurements show the interplay between parallel bulk and surface transport channels. At T < 150 K, surface state transport dominates over bulk transport. Multi-channel weak anti-localization (WAL) is observed, as a sharp cusp in the magnetoconductivity, indicating strong spin-orbit coupling. The presence of top and bottom topological surface states (TSS), including a pair of electrically coupled Rashba surface states (RSS), are indicated. Non-linear Hall effect, explained by a two-band model, further supports this interpretation. Finally, a low-T logarithmic resistance upturn is analyzed using the Lu-Shen model, supporting the presence of gapless surface states with a π Berry phase.

Keywords: topological materials, electrical transport, Lu-Shen model, quantum spin liquid

Procedia PDF Downloads 109
4482 Implicit Transaction Costs and the Fundamental Theorems of Asset Pricing

Authors: Erindi Allaj

Abstract:

This paper studies arbitrage pricing theory in financial markets with transaction costs. We extend the existing theory to include the more realistic possibility that the price at which the investors trade is dependent on the traded volume. The investors in the market always buy at the ask and sell at the bid price. Transaction costs are composed of two terms, one is able to capture the implicit transaction costs and the other the price impact. Moreover, a new definition of a self-financing portfolio is obtained. The self-financing condition suggests that continuous trading is possible, but is restricted to predictable trading strategies which have left and right limit and finite quadratic variation. That is, predictable trading strategies of infinite variation and of finite quadratic variation are allowed in our setting. Within this framework, the existence of an equivalent probability measure is equivalent to the absence of arbitrage opportunities, so that the first fundamental theorem of asset pricing (FFTAP) holds. It is also proved that, when this probability measure is unique, any contingent claim in the market is hedgeable in an L2-sense. The price of any contingent claim is equal to the risk-neutral price. To better understand how to apply the theory proposed we provide an example with linear transaction costs.

Keywords: arbitrage pricing theory, transaction costs, fundamental theorems of arbitrage, financial markets

Procedia PDF Downloads 346
4481 The Antrophological Determination of Pedagogy

Authors: Sara Kakuk

Abstract:

Pedagogy has always been open to other disciplines that reflect about the educational process (philosophy, sociology, psychology, anthropology, technology, etc.). Its interdisciplinary openness puts education, as the subject of pedagogy within a broader context of the community, enabling the knowledge of other disciplines to contribute to a better understanding of the fundamental pedagogical notion of education. The purpose of pedagogy as a science serves humans, strives towards humans, must be for humans, and this is its ultimate goal. Humans are essentially dependent on education, which is also considered as a category of humans’ being, because through education an entire world develops in humans. Anthropological assumptions of humans as "deficient beings" see the solution in education, but they also indicate a wealth of shortcomings, because they provide an opportunity for enrichment and formation of culture, living and the self. In that context, this paper illustrates the determination of pedagogy through an anthropological conception of humans and the phenomenon of education. It presents a review of anthropological ideas about education, by providing an analysis of relevant literature dealing with the anthropological notion of humans, which provides fruitful conditions for a pedagogical reconsideration of education.

Keywords: pedagogy, education, humans, anthropology, culture

Procedia PDF Downloads 437
4480 A High-Level Co-Evolutionary Hybrid Algorithm for the Multi-Objective Job Shop Scheduling Problem

Authors: Aydin Teymourifar, Gurkan Ozturk

Abstract:

In this paper, a hybrid distributed algorithm has been suggested for the multi-objective job shop scheduling problem. Many new approaches are used at design steps of the distributed algorithm. Co-evolutionary structure of the algorithm and competition between different communicated hybrid algorithms, which are executed simultaneously, causes to efficient search. Using several machines for distributing the algorithms, at the iteration and solution levels, increases computational speed. The proposed algorithm is able to find the Pareto solutions of the big problems in shorter time than other algorithm in the literature. Apache Spark and Hadoop platforms have been used for the distribution of the algorithm. The suggested algorithm and implementations have been compared with results of the successful algorithms in the literature. Results prove the efficiency and high speed of the algorithm.

Keywords: distributed algorithms, Apache Spark, Hadoop, job shop scheduling, multi-objective optimization

Procedia PDF Downloads 354
4479 Evaluation of the Self-Efficacy and Learning Experiences of Final year Students of Computer Science of Southwest Nigerian Universities

Authors: Olabamiji J. Onifade, Peter O. Ajayi, Paul O. Jegede

Abstract:

This study aimed at investigating the preparedness of the undergraduate final year students of Computer Science as the next entrants into the workplace. It assessed their self-efficacy in computational tasks and examined the relationship between their self-efficacy and their learning experiences in Southwest Nigerian universities. The study employed a descriptive survey research design. The population of the study comprises all the final year students of Computer Science. A purposive sampling technique was adopted in selecting a representative sample of interest from the final year students of Computer Science. The Students’ Computational Task Self-Efficacy Questionnaire (SCTSEQ) was used to collect data. Mean, standard deviation, frequency, percentages, and linear regression were used for data analysis. The result obtained revealed that the final year students of Computer Science were averagely confident in performing computational tasks, and there is a significant relationship between the learning experiences of the students and their self-efficacy. The study recommends that the curriculum be improved upon to accommodate industry experts as lecturers in some of the courses, make provision for more practical sessions, and the learning experiences of the student be considered an important component in the undergraduate Computer Science curriculum development process.

Keywords: computer science, learning experiences, self-efficacy, students

Procedia PDF Downloads 133
4478 Flushing Model for Artificial Islands in the Persian Gulf

Authors: Sawsan Eissa, Momen Gharib, Omnia Kabbany

Abstract:

A flushing numerical study has been performed for intended artificial islands on the Persian Gulf coast in Abu Dhabi, UAE. The island masterplan was tested for flushing using the DELFT 3D hydrodynamic model, and it was found that its residence time exceeds the acceptable PIANC flushing Criteria. Therefore, a number of mitigation measures were applied and tested one by one using the flushing model. Namely, changing the location of the entrance opening, dredging, removing part of the mangrove existing in the near vicinity to create a channel, removing the mangrove altogether, using culverts of different numbers and locations, and pumping at selected points. The pumping option gave the best solution, but it was disregarded due to high capital and running costs. Therefore, it opted for a combination of other solutions, including removing mangroves, introducing culverts, and adjusting island boundaries and types of protection.

Keywords: hydrodynamics, flushing, delft 3d, Persian Gulf, artificial islands.

Procedia PDF Downloads 42