Search results for: interstitial fluid pressure
1536 Mixed Matrix Membranes Based on [M₂(DOBDC)] (M = Mg, Co, Ni) and Polydimethylsiloxane for CO₂/N₂ Separation
Authors: Hyunuk Kim, Yang No Yun, Muhammad Sohail, Jong-Ho Moon, Young Cheol Park
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Metal-organic frameworks (MOFs), which are emerging absorbents assembled from metal ions and organic ligands, have attracted attention for their permanent porosity and design of tunable pore size. These microporous materials showed interesting properties for CO₂ storage and separation. In particular, MOFs with high surface area and open metal sites showed the remarkable adsorption capacity and selectivity for CO₂. [Mg₂ (DOBDC)] (DOBDC = 2,5-dioxidobenzene-1,4-dicarboxylate) (MOF-74 or CPO-27) is a well-known absorbent showing an exceptionally high CO₂ sorption capacity at low partial pressure and room temperature. In this work, we synthesized [M₂(DOBDC)(DMF)₂] (M = Mg, Co, Ni) and determined their single-crystal structures by X-ray crystallography. The removal of coordinated guest molecules generates Lewis acidic sites and showed high CO₂ adsorption affinity. Both CO₂ adsorption capacity and surface area are much higher than reported values in literature. To fabricate MMMs, microcrystalline [M₂ (DOBDC)(DMF)₂] was synthesized by microwave reaction and dispersed in PDMS solution. The MMMs with a various amount of [M₂ (DOBDC)(DMF) ₂] in PDMS were fabricated by a solution casting method. [M₂ (DOBDC)(DMF)₂]@PDMS membrane showed higher CO2 permeability and CO₂/N₂ selectivity than those of PDMS. Therefore, we believe that MMMs combining polymer and MOFs provide new materials for CO₂ separation technology.Keywords: metal-organic frameworks, mixed matrix membrane, CO2/N2 separation, polydimethylsiloxane (PDMS)
Procedia PDF Downloads 1991535 Preparation and Characterization of Phosphate-Nickel-Titanium Composite Coating Obtained by Sol Gel Process for Corrosion Protection
Authors: Khalidou Ba, Abdelkrim Chahine, Mohamed Ebn Touhami
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A strong industrial interest is focused on the development of coatings for anticorrosion protection. In this context, phosphate composite materials are expanding strongly due to their chemical characteristics and their interesting physicochemical properties. Sol-gel coatings offer high homogeneity and purity that may lead to obtain coating presenting good adhesion to metal surface. The goal behind this work is to develop efficient coatings for corrosion protection of steel to extend its life. In this context, a sol gel process allowing to obtain thin film coatings on carbon steel with high resistance to corrosion has been developed. The optimization of several experimental parameters such as the hydrolysis time, the temperature, the coating technique, the molar ratio between precursors, the number of layers and the drying mode has been realized in order to obtain a coating showing the best anti-corrosion properties. The effect of these parameters on the microstructure and anticorrosion performance of the films sol gel coating has been investigated using different characterization methods (FTIR, XRD, Raman, XPS, SEM, Profilometer, Salt Spray Test, etc.). An optimized coating presenting good adhesion and very stable anticorrosion properties in salt spray test, which consists of a corrosive attack accelerated by an artificial salt spray consisting of a solution of 5% NaCl, pH neutral, under precise conditions of temperature (35 °C) and pressure has been obtained.Keywords: sol gel, coating, corrosion, XPS
Procedia PDF Downloads 1231534 Suggestion of Two-Step Traction Therapy for Safer and More Effective Conservative Treatment for Low Back Pain
Authors: Won Man Park, Dae Kyung Choi, Kyungsoo Kim, Yoon Hyuk Kim
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Traction therapy has been used in the treatment of spinal pain for decades. However, a case study reported the occurrence of large disc protrusion during motorized traction therapy. In this study, we hypothesized that additional local decompression with a global axial traction could be helpful for risk reduction of intervertebral disc damage. A validated three dimensional finite element model of the lumbar spine was used. Two-step traction therapy using the axial global traction (the first step) with 1/3 body weight and the additional local decompression (the second step) with 7 mm translation of L4 spinal bone was determined for the traction therapy. During two-step traction therapy, the sacrum was constrained in all translational directions. Reduced lordosis angle by the global axial traction recovered with the additional local decompression. Stress on fibers of the annulus fibrosus by the axial global traction decreased with the local decompression by 17%~96% in the posterior region of intervertebral disc. Stresses on ligaments except anterior longitudinal ligaments in all motion segments decreased till 4.9 mm~5.6 mm translation of L4 spinal bone. The results of this study showed that the additional local decompression is very useful for reducing risk of damage in the intervertebral disc and ligaments caused by the global axial traction force. Moreover, the local decompression could be used to enhance reduction of intradiscal pressure.Keywords: lumbar spine, traction-therapy, biomechanics, finite element analysis
Procedia PDF Downloads 4771533 Study on Properties of Carbon-based Layer for Proton Exchange Membrane Fuel Cell Application
Authors: Pei-Jung Wu, Ching-Ying Huang, Chih-Chia Lin, Chun-Han Li, Chien-Yuan Wang
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The fuel cell market has considerable development potential, but the cost is still less competitive. Replacing the traditional graphite plate with a stainless steel plate as a bipolar plate can greatly reduce the weight and volume of the stack, and has more cost advantages. However, the passivation layer on the surface of stainless steel makes the contact resistance reach the ohmic level and reduces the performance of the fuel cell. Therefore, it is necessary to reduce the interfacial contact resistance through the surface treatment. In this research, the thickness, uniformity, interfacial contact resistance (ICR), and adhesion of the carbon-based layer was analyzed. On the other hand, the effect of coating properties on the performance of the fuel cell was verified through I-V tests. The results show that after coating the contact resistance is greatly reduced by three stages to the microohm level, and as the film thickness is reduced, the contact resistance is reduced from 229~118 mΩ-cm² to 135~73 mΩ-cm² at a general assembly pressure of 1 to 2 MPa., and the current density at 0.6 V increased from 485.7 mA/cm² to 575.7 mA/cm². This study verifies the importance of the uniformity and ICR of the coating on proton exchange membrane fuel cell (PEMFC), and the surface coating technology is the key to affecting the characteristics of the coating.Keywords: contact resistance, proton exchange membrane fuel cell, PEMFC, SS bipolar plate, spray coating process
Procedia PDF Downloads 2001532 Data Centers’ Temperature Profile Simulation Optimized by Finite Elements and Discretization Methods
Authors: José Alberto García Fernández, Zhimin Du, Xinqiao Jin
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Nowadays, data center industry faces strong challenges for increasing the speed and data processing capacities while at the same time is trying to keep their devices a suitable working temperature without penalizing that capacity. Consequently, the cooling systems of this kind of facilities use a large amount of energy to dissipate the heat generated inside the servers, and developing new cooling techniques or perfecting those already existing would be a great advance in this type of industry. The installation of a temperature sensor matrix distributed in the structure of each server would provide the necessary information for collecting the required data for obtaining a temperature profile instantly inside them. However, the number of temperature probes required to obtain the temperature profiles with sufficient accuracy is very high and expensive. Therefore, other less intrusive techniques are employed where each point that characterizes the server temperature profile is obtained by solving differential equations through simulation methods, simplifying data collection techniques but increasing the time to obtain results. In order to reduce these calculation times, complicated and slow computational fluid dynamics simulations are replaced by simpler and faster finite element method simulations which solve the Burgers‘ equations by backward, forward and central discretization techniques after simplifying the energy and enthalpy conservation differential equations. The discretization methods employed for solving the first and second order derivatives of the obtained Burgers‘ equation after these simplifications are the key for obtaining results with greater or lesser accuracy regardless of the characteristic truncation error.Keywords: Burgers' equations, CFD simulation, data center, discretization methods, FEM simulation, temperature profile
Procedia PDF Downloads 1581531 Multimodal Database of Retina Images for Africa: The First Open Access Digital Repository for Retina Images in Sub Saharan Africa
Authors: Simon Arunga, Teddy Kwaga, Rita Kageni, Michael Gichangi, Nyawira Mwangi, Fred Kagwa, Rogers Mwavu, Amos Baryashaba, Luis F. Nakayama, Katharine Morley, Michael Morley, Leo A. Celi, Jessica Haberer, Celestino Obua
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Purpose: The main aim for creating the Multimodal Database of Retinal Images for Africa (MoDRIA) was to provide a publicly available repository of retinal images for responsible researchers to conduct algorithm development in a bid to curb the challenges of ophthalmic artificial intelligence (AI) in Africa. Methods: Data and retina images were ethically sourced from sites in Uganda and Kenya. Data on medical history, visual acuity, ocular examination, blood pressure, and blood sugar were collected. Retina images were captured using fundus cameras (Foru3-nethra and Canon CR-Mark-1). Images were stored on a secure online database. Results: The database consists of 7,859 retinal images in portable network graphics format from 1,988 participants. Images from patients with human immunodeficiency virus were 18.9%, 18.2% of images were from hypertensive patients, 12.8% from diabetic patients, and the rest from normal’ participants. Conclusion: Publicly available data repositories are a valuable asset in the development of AI technology. Therefore, is a need for the expansion of MoDRIA so as to provide larger datasets that are more representative of Sub-Saharan data.Keywords: retina images, MoDRIA, image repository, African database
Procedia PDF Downloads 1121530 Non-Linear Velocity Fields in Turbulent Wave Boundary Layer
Authors: Shamsul Chowdhury
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The objective of this paper is to present the detailed analysis of the turbulent wave boundary layer produced by progressive finite-amplitude waves theory. Most of the works have done for the mass transport in the turbulent boundary layer assuming the eddy viscosity is not time varying, where the sediment movement is induced by the mean velocity. Near the ocean bottom, the waves produce a thin turbulent boundary layer, where the flow is highly rotational, and shear stress associated with the fluid motion cannot be neglected. The magnitude and the predominant direction of the sediment transport near the bottom are known to be closely related to the flow in the wave induced boundary layer. The magnitude of water particle velocity at the Crest phase differs from the one of the Trough phases due to the non-linearity of the waves, which plays an important role to determine the sediment movement. The non-linearity of the waves become predominant in the surf zone area, where the sediment movement occurs vigorously. Therefore, in order to describe the flow near the bottom and relationship between the flow and the movement of the sediment, the analysis was done using the non-linear boundary layer equation and the finite amplitude wave theory was applied to represent the velocity fields in the turbulent wave boundary layer. At first, the calculation was done for turbulent wave boundary layer by two-dimensional model where throughout the calculation is non-linear. But Stokes second order wave profile is adopted at the upper boundary. The calculated profile was compared with the experimental data. Finally, the calculation is done based on various modes of the velocity and turbulent energy. The mean velocity is found to differ from condition of the relative depth and the roughness. It is also found that due to non-linearity, the absolute value for velocity and turbulent energy as well as Reynolds stress are asymmetric. The mean velocity of the laminar boundary layer is always positive but in the turbulent boundary layer plays a very complicated role.Keywords: wave boundary, mass transport, mean velocity, shear stress
Procedia PDF Downloads 2551529 Finite Element Analysis and Design Optimization of Stent and Balloon System
Authors: V. Hashim, P. N. Dileep
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Stent implantation is being seen as the most successful method to treat coronary artery diseases. Different types of stents are available in the market these days and the success of a stent implantation greatly depends on the proper selection of a suitable stent for a patient. Computer numerical simulation is the cost effective way to choose the compatible stent. Studies confirm that the design characteristics of stent do have great importance with regards to the pressure it can sustain, the maximum displacement it can produce, the developed stress concentration and so on. In this paper different designs of stent were analyzed together with balloon to optimize the stent and balloon system. Commercially available stent Palmaz-Schatz has been selected for analysis. Abaqus software is used to simulate the system. This work is the finite element analysis of the artery stent implant to find out the design factors affecting the stress and strain. The work consists of two phases. In the first phase, stress distribution of three models were compared - stent without balloon, stent with balloon of equal length and stent with balloon of extra length than stent. In second phase, three different design models of Palmaz-Schatz stent were compared by keeping the balloon length constant. The results obtained from analysis shows that, the design of the strut have strong effect on the stress distribution. A design with chamfered slots found better results. The length of the balloon also has influence on stress concentration of the stent. Increase in length of the balloon will reduce stress, but will increase dog boning effect.Keywords: coronary stent, finite element analysis, restenosis, stress concentration
Procedia PDF Downloads 6181528 Allelic Diversity of Productive, Reproductive and Fertility Traits Genes of Buffalo and Cattle
Authors: M. Moaeen-ud-Din, G. Bilal, M. Yaqoob
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Identification of genes of importance regarding production traits in buffalo is impaired by a paucity of genomic resources. Choice to fill this gap is to exploit data available for cow. The cross-species application of comparative genomics tools is potential gear to investigate the buffalo genome. However, this is dependent on nucleotide sequences similarity. In this study gene diversity between buffalo and cattle was determined by using 86 gene orthologues. There was about 3% difference in all genes in term of nucleotide diversity; and 0.267±0.134 in amino acids indicating the possibility for successfully using cross-species strategies for genomic studies. There were significantly higher non synonymous substitutions both in cattle and buffalo however, there was similar difference in term of dN – dS (4.414 vs 4.745) in buffalo and cattle respectively. Higher rate of non-synonymous substitutions at similar level in buffalo and cattle indicated a similar positive selection pressure. Results for relative rate test were assessed with the chi-squared test. There was no significance difference on unique mutations between cattle and buffalo lineages at synonymous sites. However, there was a significance difference on unique mutations for non synonymous sites indicating ongoing mutagenic process that generates substitutional mutation at approximately the same rate at silent sites. Moreover, despite of common ancestry, our results indicate a different divergent time among genes of cattle and buffalo. This is the first demonstration that variable rates of molecular evolution may be present within the family Bovidae.Keywords: buffalo, cattle, gene diversity, molecular evolution
Procedia PDF Downloads 4811527 Relationship between Personality Traits and Postural Stability among Czech Military Combat Troops
Authors: K. Rusnakova, D. Gerych, M. Stehlik
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Postural stability is a complex process involving actions of biomechanical, motor, sensory and central nervous system components. Numerous joint systems, muscles involved, the complexity of sporting movements and situations require perfect coordination of the body's movement patterns. To adapt to a constantly changing situation in such a dynamic environment as physical performance, optimal input of information from visual, vestibular and somatosensory sensors are needed. Combat soldiers are required to perform physically and mentally demanding tasks in adverse conditions, and poor postural stability has been identified as a risk factor for lower extremity musculoskeletal injury. The aim of this study is to investigate whether some personality traits are related to the performance of static postural stability among soldiers of combat troops. NEO personality inventory (NEO-PI-R) was used to identify personality traits and the Nintendo Wii Balance Board was used to assess static postural stability of soldiers. Postural stability performance was assessed by changes in center of pressure (CoP) and center of gravity (CoG). A posturographic test was performed for 60 s with eyes opened during quiet upright standing. The results showed that facets of neuroticism and conscientiousness personality traits were significantly correlated with measured parameters of CoP and CoG. This study can help for better understanding the relationship between personality traits and static postural stability. The results can be used to optimize the training process at the individual level.Keywords: neuroticism, conscientiousness, postural stability, combat troops
Procedia PDF Downloads 1351526 Numerical Investigation of the Performance of a Vorsyl Separator Using a Euler-Lagrange Approach
Authors: Guozhen Li, Philip Hall, Nick Miles, Tao Wu, Jie Dong
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This paper presents a Euler-Lagrange model of the water-particles multiphase flows in a Vorsyl separator where particles with different densities are separated. A series of particles with their densities ranging from 760 kg/m3 to 1380 kg/m3 were fed into the Vorsyl separator with water by means of tangential inlet. The simulation showed that the feed materials acquired centrifugal force which allows most portion of the particles with a density less than water to move to the center of the separator, enter the vortex finder and leave the separator through the bottom outlet. While the particles heavier than water move to the wall, reach the throat area and leave the separator through the side outlet. The particles were thus separated and particles collected at the bottom outlet are pure and clean. The influence of particle density on separation efficiency was investigated which demonstrated a positive correlation of the separation efficiency with increasing density difference between medium liquid and the particle. In addition, the influence of the split ratio on the performance was studied which showed that the separation efficiency of the Vorsyl separator can be improved by the increase of split ratio. The simulation also suggested that the Vorsyl separator may not function when the feeding velocity is smaller than a certain critical feeding in velocity. In addition, an increasing feeding velocity gives rise to increased pressure drop, however does not necessarily increase the separation efficiency.Keywords: Vorsyl separator, separation efficiency, CFD, split ratio
Procedia PDF Downloads 3361525 Laboratory Scale Experimental Studies on CO₂ Based Underground Coal Gasification in Context of Clean Coal Technology
Authors: Geeta Kumari, Prabu Vairakannu
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Coal is the largest fossil fuel. In India, around 37 % of coal resources found at a depth of more than 300 meters. In India, more than 70% of electricity production depends on coal. Coal on combustion produces greenhouse and pollutant gases such as CO₂, SOₓ, NOₓ, and H₂S etc. Underground coal gasification (UCG) technology is an efficient and an economic in-situ clean coal technology, which converts these unmineable coals into valuable calorific gases. The UCG syngas (mainly H₂, CO, CH₄ and some lighter hydrocarbons) which can utilized for the production of electricity and manufacturing of various useful chemical feedstock. It is an inherent clean coal technology as it avoids ash disposal, mining, transportation and storage problems. Gasification of underground coal using steam as a gasifying medium is not an easy process because sending superheated steam to deep underground coal leads to major transportation difficulties and cost effective. Therefore, for reducing this problem, we have used CO₂ as a gasifying medium, which is a major greenhouse gas. This paper focus laboratory scale underground coal gasification experiment on a coal block by using CO₂ as a gasifying medium. In the present experiment, first, we inject oxygen for combustion for 1 hour and when the temperature of the zones reached to more than 1000 ºC, and then we started supplying of CO₂ as a gasifying medium. The gasification experiment was performed at an atmospheric pressure of CO₂, and it was found that the amount of CO produced due to Boudouard reaction (C+CO₂ 2CO) is around 35%. The experiment conducted to almost 5 hours. The maximum gas composition observed, 35% CO, 22 % H₂, and 11% CH4 with LHV 248.1 kJ/mol at CO₂/O₂ ratio 0.4 by volume.Keywords: underground coal gasification, clean coal technology, calorific value, syngas
Procedia PDF Downloads 2231524 Unveiling Electrical Treeing Mechanisms in Epoxy Resin Insulation Degradation
Authors: Chien-Kuo Chang, You-Syuan Wu, Min-Chiu Wu, Bharath-Kumar Boyanapalli
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The electrical treeing mechanism in epoxy resin insulation is a critical area of study concerning the degradation of high-voltage electrical equipment. In this study, we conducted pressure-induced degradation experiments on epoxy resin specimens using a needle-plane electrode structure to simulate electrical treeing. The specimens featured two different defect spacings, allowing for detailed observation facilitated by time-lapse photography. Our investigation revealed four distinct stages of insulation degradation: initial dark tree growth, filamentary tree growth, reverse tree growth, and eventual insulation breakdown. The initial dark treeing stage, though shortest in duration, exhibited a thicker main branch and shorter branching, ceasing upon the appearance of filamentary treeing. Filamentary treeing manifested in two forms: dark filamentary treeing during the resin's glassy state, characterized by branching structures, and fuzzy filamentary treeing during the rubbery state, resembling white feathers. The channels formed by filamentary treeing were observed to be as narrow as a few micrometers and continued to grow until the end of the experiment. Additionally, the transition to reverse treeing occurred when filamentary treeing reached the ground electrode, with the earliest manifestation being growth from the ground electrode towards the high-voltage end.Keywords: epoxy resin insulation, high-voltage equipment, electrical treeing mechanism
Procedia PDF Downloads 651523 Neurological Complications of HIV/AIDS: Case of Meningitis Caused by Cryptococcus neoformans and Tuberculous Meningitis
Authors: Ndarusanze Berchmans
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This research work focused on the analysis of the observations of tuberculous meningitis in HIV-positive patients who were treated by the Prince Regent Charles Hospital in Bujumbura. A number of 246 seropositive patients were examined by the laboratory of Prince Regent Charles in the period between 2010 and 2015. We did a retrospective study; we used data from the registers of the laboratories mentioned above; the objective was to approach the epidemiological, biological, clinical, and therapeutic characteristics of tuberculosis meningitis infection: 124 women (50.40% of AIDS patients) and 122 men (49.59% of AIDS patients) were subject to the diagnosis by identification of cerebrospinal fluid (CSF). The average age of the patients was 30 years for this period. The population at risk has an average age of between 34 and 42 years for the years between 2010-2015. From 2010 to 2012, cases of opportunistic diseases (e.g., tuberculous meningitis and Cryptococcus neoformans meningitis), often found in immunocompromised, were observed at a high rate; in this period, there was a disturbance of the rhythm providing antiretroviral drugs to people with AIDS. The rate of the two meningitis (tuberculous meningitis and Cryptococcus neoformans meningitis) remained above 10% to gradually decrease until 2015, with the gradual return of antiretrovirals. This period records an overall average of 25 cases of tuberculous meningitis, or a percentage of 10.16%. For the year 2015, there were 4 cases of tuberculous meningitis out of a total of 35 seropositive examined (11.42%). This year's percentage shows that the number of tuberculous meningitis cases has fallen from the rate in previous years. This is the result of the care given by associations against HIV/AIDS to HIV-positive people. This decrease in cases of tuberculous meningitis is due to the acquisition of antiretrovirals by all HIV-positive people treated by hospitals. For the moment, these hospitals are taking care of many AIDS patients by providing them permanently with antiretrovirals; Besides that, there are many patients who are supported by associations whose activities are directed against HIV/AIDS.Keywords: Cryptococcus neoformans meningitis, tuberculosis meningitis, neurological complications, epidemiology of meningitis
Procedia PDF Downloads 2091522 Determination of Suction of Arid Region Soil Using Filter Paper Method
Authors: Bhavita S. Dave, Chandresh H. Solanki, Atul K. Desai
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Soils of Greater Himalayas mostly pertain to Leh & Ladakh, Lahaul & Sppiti, & high reaches to Uttarakhand. The moisture regime is aridic. The arid zone starts from Baralacha pass in Lahaul and covers the entire Spiti valley in the district of Lahaul & Spiti, Himachal Pradesh of India. Here, the present study is an attempt to determine the suction value of soil collected from the arid zone of Spiti valley for different freezing-thawing cycles considering the climate ranges of Spiti valley. Suction is the basic and most important parameter which influences the behavior of unsaturated soil. It is essential to determine the suction value of unsaturated soil before other tests like shear test, and permeability. Basically, it is the negative pore water pressure in partially saturated soil measured in terms of the height of the water column. The filter paper method has been used for the study as an economical approach to evaluate suction. It is the only method from which both contact and non-contact suction can be deduced. In this study, soil specimens were subjected to 0, 1, 3, & 5 freezing-thawing (F-T) cycles for different degrees of saturation to have a wide range of suction, and soil freezing characteristic curves (SFCC) were formulated for all F-T cycles. The result data collected from the experiments have shown best-fitted values using Fredlund & Xing model for each SFCC.Keywords: suction, arid region soil, soil freezing characteristic curve, freezing-thawing cycle
Procedia PDF Downloads 2191521 Reducing Friction Associated with Commercial Use of Biomimetics While Increasing the Potential for Using Eco Materials and Design in Industry
Authors: John P. Ulhøi
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Firms are faced with pressure to stay innovative and entrepreneurial while at the same time leaving lighter ecological footprints. Traditionally inspiration for new product development (NPD) has come from the creative in-house staff and from the marketplace. Often NPD offered by this approach has proven to be (far from) optimal for its purpose or highly (resource and energy) efficient. More recently, a bio-inspired NPD approach has surfaced under the banner of biomimetics. Biomimetics refers to inspiration from and translations of designs, systems, processes, and or specific properties that exist in nature. The principles and structures working in nature have evolved over a long period of time enable them to be optimized for the purpose and resource and energy-efficient. These characteristics reflect the raison d'être behind the field of biomimetics. While biological expertise is required to understand and explain such natural and biological principles and structures, engineers are needed to translate biological design and processes into synthetic applications. It can, therefore, hardly be surprising, biomimetics long has gained a solid foothold in both biology and engineering. The commercial adoption of biomimetic applications in new production development (NDP) in industry, however, does not quite reflect a similar growth. Differently put, this situation suggests that something is missing in the biomimetic-NPD-equation, thus acting as a brake towards the wider commercial application of biomimetics and thus the use of eco-materials and design in the industry. This paper closes some of that gap. Before concluding, avenues for future research and implications for practice will be briefly sketched out.Keywords: biomimetics, eco-materials, NPD, commercialization
Procedia PDF Downloads 1541520 IoT Based Agriculture Monitoring Framework for Sustainable Rice Production
Authors: Armanul Hoque Shaon, Md Baizid Mahmud, Askander Nobi, Md. Raju Ahmed, Md. Jiabul Hoque
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In the Internet of Things (IoT), devices are linked to the internet through a wireless network, allowing them to collect and transmit data without the need for a human operator. Agriculture relies heavily on wireless sensors, which are a vital component of the Internet of Things (IoT). This kind of wireless sensor network monitors physical or environmental variables like temperatures, sound, vibration, pressure, or motion without relying on a central location or sink and collaboratively passes its data across the network to be analyzed. As the primary source of plant nutrients, the soil is critical to the agricultural industry's continued growth. We're excited about the prospect of developing an Internet of Things (IoT) solution. To arrange the network, the sink node collects groundwater levels and sends them to the Gateway, which centralizes the data and forwards it to the sensor nodes. The sink node gathers soil moisture data, transmits the mean to the Gateways, and then forwards it to the website for dissemination. The web server is in charge of storing and presenting the moisture in the soil data to the web application's users. Soil characteristics may be collected using a networked method that we developed to improve rice production. Paddy land is running out as the population of our nation grows. The success of this project will be dependent on the appropriate use of the existing land base.Keywords: IoT based agriculture monitoring, intelligent irrigation, communicating network, rice production
Procedia PDF Downloads 1481519 Full-Field Estimation of Cyclic Threshold Shear Strain
Authors: E. E. S. Uy, T. Noda, K. Nakai, J. R. Dungca
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Cyclic threshold shear strain is the cyclic shear strain amplitude that serves as the indicator of the development of pore water pressure. The parameter can be obtained by performing either cyclic triaxial test, shaking table test, cyclic simple shear or resonant column. In a cyclic triaxial test, other researchers install measuring devices in close proximity of the soil to measure the parameter. In this study, an attempt was made to estimate the cyclic threshold shear strain parameter using full-field measurement technique. The technique uses a camera to monitor and measure the movement of the soil. For this study, the technique was incorporated in a strain-controlled consolidated undrained cyclic triaxial test. Calibration of the camera was first performed to ensure that the camera can properly measure the deformation under cyclic loading. Its capacity to measure deformation was also investigated using a cylindrical rubber dummy. Two-dimensional image processing was implemented. Lucas and Kanade optical flow algorithm was applied to track the movement of the soil particles. Results from the full-field measurement technique were compared with the results from the linear variable displacement transducer. A range of values was determined from the estimation. This was due to the nonhomogeneous deformation of the soil observed during the cyclic loading. The minimum values were in the order of 10-2% in some areas of the specimen.Keywords: cyclic loading, cyclic threshold shear strain, full-field measurement, optical flow
Procedia PDF Downloads 2291518 Defect Classification of Hydrogen Fuel Pressure Vessels using Deep Learning
Authors: Dongju Kim, Youngjoo Suh, Hyojin Kim, Gyeongyeong Kim
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Acoustic Emission Testing (AET) is widely used to test the structural integrity of an operational hydrogen storage container, and clustering algorithms are frequently used in pattern recognition methods to interpret AET results. However, the interpretation of AET results can vary from user to user as the tuning of the relevant parameters relies on the user's experience and knowledge of AET. Therefore, it is necessary to use a deep learning model to identify patterns in acoustic emission (AE) signal data that can be used to classify defects instead. In this paper, a deep learning-based model for classifying the types of defects in hydrogen storage tanks, using AE sensor waveforms, is proposed. As hydrogen storage tanks are commonly constructed using carbon fiber reinforced polymer composite (CFRP), a defect classification dataset is collected through a tensile test on a specimen of CFRP with an AE sensor attached. The performance of the classification model, using one-dimensional convolutional neural network (1-D CNN) and synthetic minority oversampling technique (SMOTE) data augmentation, achieved 91.09% accuracy for each defect. It is expected that the deep learning classification model in this paper, used with AET, will help in evaluating the operational safety of hydrogen storage containers.Keywords: acoustic emission testing, carbon fiber reinforced polymer composite, one-dimensional convolutional neural network, smote data augmentation
Procedia PDF Downloads 861517 Estimation of Energy Efficiency of Blue Hydrogen Production Onboard of Ships
Authors: Li Chin Law, Epaminondas Mastorakos, Mohd Roslee Othman, Antonis Trakakis
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The paper introduces an alternative concept of carbon capture for shipping by using pre-combustion carbon capture technology (Pre-CCS), which was proven to be less energy intensive than post-combustion carbon capture from the engine exhaust. Energy assessment on amine-based post-combustion CCS on LNG-fuelled ships showed that the energy efficiency of CCS ships reduced from 48% to 36.6%. Then, an energy assessment was carried out to compare the power and heat requirements of the most used hydrogen production methods and carbon capture technologies. Steam methane reformer (SMR) was found to be 20% more energy efficient and achieved a higher methane conversion than auto thermal reaction and methane decomposition. Next, pressure swing adsorber (PSA) has shown a lower energy requirement than membrane separation, cryogenic separation, and amine absorption in pre-combustion carbon capture. Hence, an integrated system combining SMR and PSA (SMR-PSA) with waste heat integration (WHR) was proposed. This optimized SMR-based integrated system has achieved 65% of CO₂ reduction with less than 7-percentage point of energy penalty (41.7% of energy efficiency). Further integration of post-combustion CCS with the SMR-PSA integrated system improved carbon capture rate to 86.3% with 9-percentage points of energy penalty (39% energy efficiency). The proposed system was shown to be able to meet the carbon reduction targets set by International Maritime Organization (IMO) with certain energy penalties.Keywords: shipping, decarbonisation, alternative fuels, low carbon, hydrogen, carbon capture
Procedia PDF Downloads 691516 Development of Mineral Carbonation Process from Ultramafic Tailings, Enhancing the Reactivity of Feedstocks
Authors: Sara Gardideh, Mansoor Barati
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The mineral carbonation approach for reducing global warming has garnered interest on a worldwide scale. Due to the benefits of permanent storage and abundant mineral resources, mineral carbonation (MC) is one of the most effective strategies for sequestering CO₂. The combination of mineral processing for primary metal recovery and mineral carbonation for carbon sequestration is an emerging field of study with the potential to minimize capital costs. A detailed study of low-pressures–solid carbonation of ultramafic tailings in a dry environment has been accomplished. In order to track the changing structure of serpentine minerals and their reactivity as a function of temperature (300-900 ᵒC), CO₂ partial pressure (25-90 mol %), and thermal preconditioning, thermogravimetry has been utilized. The incongruent CO₂ van der Waals molecular diameters with the octahedral-tetrahedral lattice constants of serpentine were used to explain the mild carbonation reactivity. Serpentine requires additional thermal-treatment to remove hydroxyl groups, resulting in the chemical transformation to pseudo-forsterite, which is a mineral composed of isolated SiO₄ tetrahedra linked by octahedrally coordinated magnesium ions. The heating treatment above 850 ᵒC is adequate to remove chemically bound water from the lattice. Particles with a diameter < 34 (μm) are desirable, and thermally treated serpentine at 850 ᵒC for 2.30 hours reached 65% CO₂ storage capacity. The decrease in particle size, increase in temperature, and magnetic separation can dramatically enhance carbonation.Keywords: particle size, thermogravimetry, thermal-treatment, serpentine
Procedia PDF Downloads 781515 Pastoralist Transhumance and Conflict along the Nigeria-niger Borderlands: Towards New Perspective for Effective Border Management in Africa
Authors: Abubakar Samaila
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Pastoralism has been an old practice in the Sahel region of west Africa. In recent years, pastoralists in Nigeria have increasingly been migrating on seasonal transhumance southward from the neighboring countries, especially Niger Republic, in search of better grazing conditions due to mainly, climate change. This has increased pressure on farm lands which instigate farmer-herder conflicts. These conflicts occur mainly between farmers and pastoralists but also between pastoralist groups themselves. However, there has been a shift in these conflicts recently to involve traditional institutions and, in some cases, the local authorities along the borderlands. The involvement of local institutions in the conflict has created an incentive to local actors, particularly pastoralcommunity-based groups, in responding to these violent threats. As pastoralists are mobile, these conflicts became difficult to contain and, thus, spill across borders. Consequently, the conflict has now transformed into an urbanized regional conflicts that involve some major cities along the Nigeria-Niger borderlands; Sokoto, Zamfara, and Katsina on the Nigerian side andDosso, Tahoa andMaradi in Niger republic. These areas are now experiencing unprecedented growing wave of violence that have become complex and escalates into a hydra-social conflict. The aim of this research is to investigate how the fluidities of Nigeria-Niger borderland intensified armed conflicts between the local pastoral organizations and sedentary populationspreading to some urban cities along the borderlands. The paper further suggests alternative approaches towards addressing the perennial crisis in African borderlands.Keywords: pastoralism, climate change, conflict, nigeria, niger, borderlands
Procedia PDF Downloads 841514 Thermomechanical Behavior of Asphalt Modified with Thermoplastic Polymer and Nanoclay Dellite 43B
Authors: L. F. Tamele Jr., G. Buonocore, H. F. Muiambo
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Asphalt binders play an essential role in the performance and properties of asphalt mixtures. The increase in heavy loads, greater traffic volume, and high tire pressure, combined with a substantial variation in daily and seasonal pavement temperatures, are the main responsible for the failure of asphalt pavements. To avoid or mitigate these failures, the present research proposes the use of thermoplastic polymers, HDPE and LLDPE, and nanoclay Dellite 43B for modification of asphalt in order to improve its thermomechanical and rheological properties. The nanocomposites were prepared by the solution intercalation method in a high shear mixer for a mixing time of 2 h, at 180℃ and 5000 rpm. The addition of Dellite 43B improved the physical, rheological, and thermal properties of asphalt, either separated or in the form of polymer/bitumen blends. The results of the physical characterization showed a decrease in penetration and an increase in softening point, thermal susceptibility, viscosity, and stiffness. On the other hand, thermal characterization showed that the nanocomposites have greater stability at higher temperatures by exhibiting greater amounts of residues and improved initial and final decomposition temperatures. Thus, the modification of asphalt by polymers and nanoclays seems to be a suitable solution for road pavement in countries which experiment with high temperatures combined with long heavy rain seasons.Keywords: asphalt, nanoclay dellite 43B, polymer modified asphalt, thermal and rheological properties
Procedia PDF Downloads 1401513 Variability of Climatic Elements in Nigeria Over Recent 100 Years
Authors: T. Salami, O. S. Idowu, N. J. Bello
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Climatic variability is an essential issue when dealing with the issue of climate change. Variability of some climate parameter helps to determine how variable the climatic condition of a region will behave. The most important of these climatic variables which help to determine the climatic condition in an area are both the Temperature and Precipitation. This research deals with Longterm climatic variability in Nigeria. Variables examined in this analysis include near-surface temperature, near surface minimum temperature, maximum temperature, relative humidity, vapour pressure, precipitation, wet-day frequency and cloud cover using data ranging between 1901-2010. Analyses were carried out and the following methods were used: - Regression and EOF analysis. Results show that the annual average, minimum and maximum near-surface temperature all gradually increases from 1901 to 2010. And they are in the same case in a wet season and dry season. Minimum near-surface temperature, with its linear trends are significant for annual, wet season and dry season means. However, the diurnal temperature range decreases in the recent 100 years imply that the minimum near-surface temperature has increased more than the maximum. Both precipitation and wet day frequency decline from the analysis, demonstrating that Nigeria has become dryer than before by the way of rainfall. Temperature and precipitation variability has become very high during these periods especially in the Northern areas. Areas which had excessive rainfall were confronted with flooding and other related issues while area that had less precipitation were all confronted with drought. More practical issues will be presented.Keywords: climate, variability, flooding, excessive rainfall
Procedia PDF Downloads 3791512 Preparation and Characterization of Mixed Cu-Ag-Pd Oxide Supported Catalysts for Complete Catalytic Oxidation of Methane
Authors: Ts. Lazarova, V. Tumbalev, S. Atanacova-Vladimirova, G. Ivanov, A. Naydenov, D. Kovacheva
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Methane is a major Greenhouse Gas (GHG) that accounts for 14% of the world’s total amount of GHG emissions, originating mainly from agriculture, Coal mines, land fields, wastewater and oil and gas facilities. Nowadays the problem caused by the methane emissions has been a subject of an increased concern. One of the methods for neutralization of the methane emissions is it's complete catalytic oxidation. The efforts of the researchers are focused on the development of new types of catalysts and optimizing the existing catalytic systems in order to prevent the sintering of the palladium, providing at the same time a sufficient activity at temperatures below 500oC. The aim of the present work is to prepare mixed Cu-Ag-Pd oxide catalysts supported on alumina and to test them for methane complete catalytic oxidation. Cu-Ag-Pd/Al2O3 were prepared on a γ-Al2O3 (BET surface area = 220 m2/g) by the incipient wetness method using the corresponding metal nitrates (Cu:Ag = 90:10, Cu:Pd =97:3, Cu:Ag:Pd= 87:10:3) as precursors. A second set of samples were prepared with addition of urea to the metal nitrate solutions with the above mentioned ratios assuming increased dispersivity of the catalysts. The catalyst samples were dried at 100°C for 3 hours and calcined at 550°C for 30 minutes. Catalysts samples were characterized using X-ray diffraction (XRD), low temperature adsorption of nitrogen (BET) and scanning electron microscopy (SEM). The catalytic activity tests were carried out in a continuous flow type of reactor at atmospheric pressure. The effect of catalyst aging at 500 oC for 120 h on the methane combustion activity was also investigated. The results clearly indicate the synergetic effect of Ag and Pd on the catalytic activity.Keywords: catalysts, XRD, BET, SEM, catalytic oxidation
Procedia PDF Downloads 3761511 Nano-Enhanced In-Situ and Field Up-Gradation of Heavy Oil
Authors: Devesh Motwani, Ranjana S. Baruah
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The prime incentive behind up gradation of heavy oil is to increase its API gravity for ease of transportation to refineries, thus expanding the market access of bitumen-based crude to the refineries. There has always been a demand for an integrated approach that aims at simplifying the upgrading scheme, making it adaptable to the production site in terms of economics, environment, and personnel safety. Recent advances in nanotechnology have facilitated the development of two lines of heavy oil upgrading processes that make use of nano-catalysts for producing upgraded oil: In Situ Upgrading and Field Upgrading. The In-Situ upgrading scheme makes use of Hot Fluid Injection (HFI) technique where heavy fractions separated from produced oil are injected into the formations to reintroduce heat into the reservoir along with suspended nano-catalysts and hydrogen. In the presence of hydrogen, catalytic exothermic hydro-processing reactions occur that produce light gases and volatile hydrocarbons which contribute to increased oil detachment from the rock resulting in enhanced recovery. In this way the process is a combination of enhanced heavy oil recovery along with up gradation that effectively handles the heat load within the reservoirs, reduces hydrocarbon waste generation and minimizes the need for diluents. By eliminating most of the residual oil, the Synthetic Crude Oil (SCO) is much easier to transport and more amenable for processing in refineries. For heavy oil reservoirs seriously impacted by the presence of aquifers, the nano-catalytic technology can still be implemented on field though with some additional investments and reduced synergies; however still significantly serving the purpose of production of transportable oil with substantial benefits with respect to both large scale upgrading, and known commercial field upgrading technologies currently on the market. The paper aims to delve deeper into the technology discussed, and the future compatibility.Keywords: upgrading, synthetic crude oil, nano-catalytic technology, compatibility
Procedia PDF Downloads 3981510 Endoscopic Versus Open Treatment of Carpal Tunnel Syndrome: Postoperative Complications in Patients with Diabetes Mellitus
Authors: Arman Kishan, Mark Haft, Steve Li, Duc Nguyen, Dawn Laporte
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Objective: Patients with Type 2 diabetes (T2DM) often face higher postoperative complication rates. Limited data exist on outcomes in T2DM patients undergoing carpal tunnel release (CTR). This study aims to compare complication rates between endoscopic CTR (ECTR) and open CTR (OCTR) in patients with T2DM. Methods: This was a retrospective cohort study using the TriNetX database of 56741 patients with T2DM undergoing ECTR (N= 14,949) or OCTR (N= 41,792). Demographic data, medical comorbidities, and complication rates were analyzed. We used multivariable analysis to identify differences in postoperative complication rates between the two treatment methods in patients with T2DM. Results: Patients with T2DM undergoing ECTR had a significantly lower incidence of 90-day wound infection (p < 0.001), 90-day wound dehiscence (p < 0.001), and nerve injury (p < 0.001) when compared to patients who underwent OCTR. After matching, there was a significantly higher number of T2DM patients undergoing ECTR who had peripheral vascular disease (p = 0.045) and hypertension (p = 0.020) when compared to the OCTR group. These patients also had a lower incidence of fluid and electrolyte disorders (p = 0.002) and chronic blood loss anemia (p = 0.025). Conclusion: ECTR presents a superior choice for T2DM patients undergoing CTR, yielding significantly lower rates of wound infection, wound dehiscence, and nerve injury within 90 days post-surgery—reducing the risk by 31%, 48%, and 59%, respectively. These findings support the adoption of ECTR as the preferred method in this patient population, potentially leading to improved postoperative outcomes.Keywords: endoscopic treatment of carpal tunnel syndrome, open treatment of carpal tunnel syndrome, carpal tunnel syndrome, postoperative complications in patients with diabetes mellitus
Procedia PDF Downloads 621509 From Connected Family to Disconnection for Teens
Authors: Jocelyn Lachance, Francis Jauréguiberry
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In a few years, the exceptionality of the situation of an individual who could be reached at any time and at any time was replaced by the normality of instantly hearing the voice or immediately seeing the face of the person. This participates in the transformation of our representations of time and space, which gives rise to new expectations. Expectations that parents formulate more or less clearly to their children. The obligation to remain reachable seems to be asserting itself as a general norm which, having imposed itself on adults, now extends to the youngest. In the case of parents and their children, the rationale for this ongoing connection is not always based on actual and imminent dangers. It is the potential for dangerous events that underpins the indisputable argument for the importance of remaining reachable. It is the contingent nature of the risks that imposes itself on these young people as an argument of authority. By entering this connected world, the younger generations also end up adhering in many cases to this reassuring standard of connection. Many teenagers in ours researches nonetheless firmly believe that their freedom of movement is subject to the obligation to carry their smartphone with them. In this way, a connection "pact" is generally established, concluded under pressure, which implies first and foremost that contact be possible at any time, hence the importance of keeping it within reach, and often of '' be attentive to calls and texts sent by parents, at the risk of losing a recently acquired freedom. In this context, if adolescents are growing up in a connected world today, it is also because of the connection the parents are expecting from them. In our conference, by evoking situations reported by teenagers and parents of teenagers during our surveys, we propose to think about the role of the parents in making their child connected and about the desire of the disconnection of the teens.Keywords: connection, disconnection, smartphone, parents, ritual
Procedia PDF Downloads 1841508 Detection of Helicobacter Pylori by PCR and ELISA Methods in Patients with Hyperlipidemia
Authors: Simin Khodabakhshi, Hossein Rassi
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Hyperlipidemia refers to any of several acquired or genetic disorders that result in a high level of lipids circulating in the blood. Helicobacter pylori infection is a contributing factor in the progression of hyperlipidemia with serum lipid changes. The aim of this study was to detect of Helicobacter pylori by PCR and serological methods in patients with hyperlipidemia. In this case-control study, 174 patients with hyperlipidemia and 174 healthy controls were studied. Also, demographics, physical and biochemical parameters were performed in all samples. The DNA extracted from blood specimens was amplified by H pylori cagA specific primers. The results show that H. pylori cagA positivity was detected in 79% of the hyperlipidemia and in 56% of the control group by ELISA test and 49% of the hyperlipidemia and in 24% of the control group by PCR test. Prevalence of H. pylori infection was significantly higher in hyperlipidemia as compared to controls. In addition, patients with hyperlipidemia had significantly higher values for triglyceride, total cholesterol, LDL-C, waist to hip ratio, body mass index, diastolic and systolic blood pressure and lower levels of HDL-C than control participants (all p < 0.0001). Our result detected the ELISA was a rapid and cost-effective detection and considering the high prevalence of cytotoxigenic H. pylori strains, cag A is suggested as a promising target for PCR and ELISA tests for detection of infection with toxigenic strains. In general, it can be concluded that molecular analysis of H. pylori cagA and clinical parameters are important in early detection of hyperlipidemia and atherosclerosis with H. pylori infection by PCR and ELISA tests.Keywords: Helicobacter pylori, hyperlipidemia, PCR, ELISA
Procedia PDF Downloads 1941507 Evaluation of the Power Generation Effect Obtained by Inserting a Piezoelectric Sheet in the Backlash Clearance of a Circular Arc Helical Gear
Authors: Barenten Suciu, Yuya Nakamoto
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Power generation effect, obtained by inserting a piezo- electric sheet in the backlash clearance of a circular arc helical gear, is evaluated. Such type of screw gear is preferred since, in comparison with the involute tooth profile, the circular arc profile leads to reduced stress-concentration effects, and improved life of the piezoelectric film. Firstly, geometry of the circular arc helical gear, and properties of the piezoelectric sheet are presented. Then, description of the test-rig, consisted of a right-hand thread gear meshing with a left-hand thread gear, and the voltage measurement procedure are given. After creating the tridimensional (3D) model of the meshing gears in SolidWorks, they are 3D-printed in acrylonitrile butadiene styrene (ABS) resin. Variation of the generated voltage versus time, during a meshing cycle of the circular arc helical gear, is measured for various values of the center distance. Then, the change of the maximal, minimal, and peak-to-peak voltage versus the center distance is illustrated. Optimal center distance of the gear, to achieve voltage maximization, is found and its significance is discussed. Such results prove that the contact pressure of the meshing gears can be measured, and also, the electrical power can be generated by employing the proposed technique.Keywords: circular arc helical gear, contact problem, optimal center distance, piezoelectric sheet, power generation
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