Search results for: water management
2031 Deformation of Water Waves by Geometric Transitions with Power Law Function Distribution
Authors: E. G. Bautista, J. M. Reyes, O. Bautista, J. C. Arcos
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In this work, we analyze the deformation of surface waves in shallow flows conditions, propagating in a channel of slowly varying cross-section. Based on a singular perturbation technique, the main purpose is to predict the motion of waves by using a dimensionless formulation of the governing equations, considering that the longitudinal variation of the transversal section obey a power-law distribution. We show that the spatial distribution of the waves in the varying cross-section is a function of a kinematic parameter,κ , and two geometrical parameters εh and w ε . The above spatial behavior of the surface elevation is modeled by an ordinary differential equation. The use of single formulas to model the varying cross sections or transitions considered in this work can be a useful approximation to natural or artificial geometrical configurations.
Keywords: Surface waves, Asymptotic solution, Power law function, Non-dispersive waves.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18582030 RBF modeling of Incipient Motion of Plane Sand Bed Channels
Authors: Gopu Sreenivasulu, Bimlesh Kumar, Achanta Ramakrishna Rao
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To define or predict incipient motion in an alluvial channel, most of the investigators use a standard or modified form of Shields- diagram. Shields- diagram does give a process to determine the incipient motion parameters but an iterative one. To design properly (without iteration), one should have another equation for resistance. Absence of a universal resistance equation also magnifies the difficulties in defining the model. Neural network technique, which is particularly useful in modeling a complex processes, is presented as a tool complimentary to modeling incipient motion. Present work develops a neural network model employing the RBF network to predict the average velocity u and water depth y based on the experimental data on incipient condition. Based on the model, design curves have been presented for the field application.Keywords: Incipient motion, Prediction error, Radial-Basisfunction, Sediment transport, Shields' diagram.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15072029 Research on the Protection and Development of Ancient Town Cultural Landscape Based on "Four State" Elements: Illustrated by the Example of Qikou
Authors: Bian Cheng Xiang, Wang Qian
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With the deepening of the research on the connotation of cultural heritage and human geography, cultural landscape takes landscape as a cultural product, integrates and blends cultural and natural heritage to explore the cultural value behind its material landscape. Qikou ancient town is a typical traditional settlement with homomorphism of mountain and water veins. Its cultural accumulation and natural landscape play an important role in its development. Therefore, this paper will combine the material and cultural elements of Qikou ancient town to analyze the composition of the cultural landscape of the ancient town, and explore the protection and utilization of the cultural landscape of Qikou ancient town from the four aspects of ecology, form, cultural form and business form, so as to provide effective strategies for the development of the ancient town.
Keywords: Four states, cultural landscape, ancient town, sustainable development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1742028 Sickle Cell Disease: Review of Managements in Pregnancy and the Outcome in Ampang Hospital, Selangor
Authors: Z. Nurzaireena, K. Azalea, T. Azirawaty, S. Jameela, G. Muralitharan
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The aim of this study is the review of the management practices of sickle cell disease patients during pregnancy, as well as the maternal and neonatal outcome at Ampang Hospital, Selangor. The study consisted of a review of pregnant patients with sickle cell disease under follow up at the Hematology Clinic, Ampang Hospital over the last seven years to assess their management and maternal-fetal outcome. The results of the review show that Ampang Hospital is considered the public hematology centre for sickle cell disease and had successfully managed three pregnancies throughout the last seven years. Patients’ presentations, managements and maternal-fetal outcome were compared and reviewed for academic improvements. All three patients were seen very early in their pregnancy and had been given a regime of folic acid, antibiotics and thrombo-prophylactic drugs. Close monitoring of maternal and fetal well being was done by the hematologists and obstetricians. Among the patients, there were multiple admissions during the pregnancy for either a painful sickle cell bone crisis, haemolysis following an infection and anemia requiring phenotype- matched blood and exchange transfusions. Broad spectrum antibiotics coverage during and infection, hydration, pain management and venous-thrombolism prophylaxis were mandatory. The pregnancies managed to reach near term in the third trimester but all required emergency caesarean section for obstetric indications. All pregnancies resulted in live births with good fetal outcome. During post partum all were nursed closely in the high dependency units for further complications and were discharged well. Post partum follow up and contraception counseling was comprehensively given for future pregnancies. Sickle cell disease is uncommonly seen in the East, especially in the South East Asian region, yet more cases are seen in the current decade due to improved medical expertise and advance medical laboratory technologies. Pregnancy itself is a risk factor for sickle cell patients as increased thrombosis event and risk of infections can lead to multiple crisis, haemolysis, anemia and vaso-occlusive complications including eclampsia, cerebrovasular accidents and acute bone pain. Patients mostly require multiple blood product transfusions thus phenotype-matched blood is required to reduce the risk of alloimmunozation. Emphasizing the risks and complications in preconception counseling and establishing an ultimate pregnancy plan would probably reduce the risk of morbidity and mortality to the mother and unborn child. Early management for risk of infection, thromboembolic events and adequate hydration is mandatory. A holistic approach involving multidisciplinary team care between the hematologist, obstetricians, anesthetist, neonatologist and close nursing care for both mother and baby would ensure the best outcome. In conclusion, sickle cell disease by itself is a high risk medical condition and pregnancy would further amplify the risk. Thus, close monitoring with combine multidisciplinary care, counseling and educating the patients are crucial in achieving the safe outcome.Keywords: Anemia, haemoglobinopathies, pregnancy, sickle cell disease.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12952027 Turbulence Modeling and Wave-Current Interactions
Authors: A.-C. Bennis, F. Dumas, F. Ardhuin, B. Blanke
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The mechanics of rip currents are complex, involving interactions between waves, currents, water levels and the bathymetry, that present particular challenges for numerical models. Here, the effects of a grid-spacing dependent horizontal mixing on the wave-current interactions are studied. Near the shore, wave rays diverge from channels towards bar crests because of refraction by topography and currents, in a way that depends on the rip current intensity which is itself modulated by the horizontal mixing. At low resolution with the grid-spacing dependent horizontal mixing, the wave motion is the same for both coupling modes because the wave deviation by the currents is weak. In high resolution case, however, classical results are found with the stabilizing effect of the flow by feedback of waves on currents. Lastly, wave-current interactions and the horizontal mixing strongly affect the intensity of the three-dimensional rip velocity.
Keywords: Numerical modeling, Rip currents, Turbulence modeling, Wave-current interactions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 22072026 Use of Pesticides and Their Role in Environmental Pollution
Authors: Muhammad Jamil Khan, Muhammad Sharif Zia, Muhammad Qasim
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Insect pests are the major source of crop damage, yield and quality reduction in Pakistan and else where in the world. Cotton crop is the most hit crop in Pakistan followed by rice and the second most important foreign exchange earning crop. A wide variety of staple, horticultural and cash crops grown, reflect serious problems of many types of insect pests. To overcome the insect pest problem, pesticide use in Pakistan has increased substantially which has now been further intensified. Pesticides worth more than billions of rupees are imported every year. This paper reviews the over all pesticide use in Pakistan in relation to pesticide prices, support price of cotton and rice, pesticide use in different provinces of Pakistan on different crops and their impact on crop productivity. The environmental pollution caused by the use of pesticides, contamination of soil and water resources and the danger associated with the disposal of their empty containers is also discussed in detail.Keywords: Pesticide use, crop productivity, environmentalpollution
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35072025 Research on the Methodologies of the Opportune Innovation - A Case Study of BYD
Authors: Guangjie Liu
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The main purpose of this paper is to research on the methodologies of BYD to implement the opportune innovation. BYD is a Chinese company which has the IT component manufacture, the rechargeable battery and the automobile businesses. The paper deals with the innovation methodology as the same as the IPR management BYD implements in order to obtain the rapid growth of technology development with the reasonable cost of money and time.Keywords: Opportune innovation, vertical integration, unpatenting integration, patenting.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28602024 New Effect of Duct Cross Sectional Shape on the Nanofluid Flow Heat Transfer
Authors: Mohammad R. Salimpour, Amir Dehshiri
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In the present article, we investigate experimental laminar forced convective heat transfer specifications of TiO2/water nanofluids through conduits with different cross sections. we check the effects of different parameters such as cross sectional shape, Reynolds number and concentration of nanoparticles in stable suspension on increasing convective heat transfer by designing and assembling of an experimental apparatus. The results demonstrate adding a little amount of nanoparticles to the base fluid, improves heat transfer behavior in conduits. Moreover, conduit with circular cross-section has better performance compared to the square and triangular cross sections. However, conduits with square and triangular cross sections have more relative heat transfer enchantment than conduit with circular cross section.Keywords: Nanofluid, cross-sectional shape, TiO2, convection.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10822023 Fuzzy Logic and Control Strategies on a Sump
Authors: Nasser Mohamed Ramli, Nurul Izzati Zulkifli
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Sump can be defined as a reservoir which contains slurry; a mixture of solid and liquid or water, in it. Sump system is an unsteady process owing to the level response. Sump level shall be monitored carefully by using a good controller to avoid overflow. The current conventional controllers would not be able to solve problems with large time delay and nonlinearities, Fuzzy Logic controller is tested to prove its ability in solving the listed problems of slurry sump. Therefore, in order to justify the effectiveness and reliability of these controllers, simulation of the sump system was created by using MATLAB and the results were compared. According to the result obtained, instead of Proportional-Integral (PI) and Proportional-Integral and Derivative (PID), Fuzzy Logic controller showed the best result by offering quick response of 0.32 s for step input and 5 s for pulse generator, by producing small Integral Absolute Error (IAE) values that are 0.66 and 0.36 respectively.
Keywords: Fuzzy, sump, level, controller.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7822022 Elasticity Model for Easing Peak Hour Demand for Metrorail Transport System
Authors: P. K. Sarkar, Amit Kumar Jain
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The demand for Urban transportation is characterised by a large scale temporal and spatial variations which causes heavy congestion inside metro trains in peak hours near Centre Business District (CBD) of the city. The conventional approach to address peak hour congestion, metro trains has been to increase the supply by way of introduction of more trains, increasing the length of the trains, optimising the time table to increase the capacity of the system. However, there is a limitation of supply side measures determined by the design capacity of the systems beyond which any addition in the capacity requires huge capital investments. The demand side interventions are essentially required to actually spread the demand across the time and space. In this study, an attempt has been made to identify the potential Transport Demand Management tools applicable to Urban Rail Transportation systems with a special focus on differential pricing. A conceptual price elasticity model has been developed to analyse the effect of various combinations of peak and nonpeak hoursfares on demands. The elasticity values for peak hour, nonpeak hour and cross elasticity have been assumed from the relevant literature available in the field. The conceptual price elasticity model so developed is based on assumptions which need to be validated with actual values of elasticities for different segments of passengers. Once validated, the model can be used to determine the peak and nonpeak hour fares with an objective to increase overall ridership, revenue, demand levelling and optimal utilisation of assets.Keywords: Congestion, differential pricing, elasticity, transport demand management, urban transportation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16872021 Application of Nano-Zero Valent Iron for Treating Metolachlor in Aqueous Solution
Authors: P. Suntornchot, T. Satapanajaru, S.D. Comfort
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Water, soil and sediment contaminated with metolachlor poses a threat to the environment and human health. We determined the effectiveness of nano-zerovalent iron (NZVI) to dechlorinate metolachlor [2-chloro-n-(2-ethyl-6-methyl-phenyl)-n- (1-methoxypropan-2-yl)acetamide] in pH solution and the presence of aluminium salt. The optimum dosage of degradation of 100 mlL-1 metolachlor was 1% (w/v) NZVI. The degradation kinetic rate (kobs) was 0.218×10-3 min-1 and specific first-order rates (kSA) was 8.72×10-7 L m-2min-1. By treating aqueous solutions of metolachlor with NZVI, metolachlor destruction rate were increased as the pH decrease from 10 to 4. Lowering solution pH removes Fe (III) passivating layers from the NZVI and makes it free for reductive transformations. Destruction kinetic rates were 20.8×10-3 min-1 for pH4, 18.9×10-3 min-1 for pH7, 13.8×10-3 min-1 for pH10. In addition, destruction kinetic of metolachlor by NZVI was enhanced when aluminium sulfate was added. The destruction kinetic rate were 20.4×10-3 min-1 for 0.05% Al(SO4)3 and 60×10-3 min-1 for 0.1% Al(SO4)3.Keywords: destruction, kinetic rate, metolachlor, nano-zerovalent iron
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14102020 Combined Hydrothermal Synthesis of Zinc and Magnesium Borates at 100oC Using ZnO, MgO and H3BO3
Authors: N. Tugrul, A. S. Kipcak, N. Baran Acarali, E. Moroydor Derun, S. Piskin
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Magnesium borate(MB) istechnical ceramic for high heat-resisting, corrosion-resisting, super mechanical strength, superinsulation, light weight, high strength, and high coefficient of elasticity. Zinc borate (ZB) can be used as multi-functional synergistic additives with flame retardant additives in polymers. The most important properties are low solubility in water and high dehydration temperature. ZB dehydrates above 290°C and anhydrous ZB has thermal resistance about 400°C. In this study, the raw materials of ZnO, MgO and H3BO3 were used with mole ratio of 1:1:9. With the starting materials hydrothermal method was applied at a temperature of 100oC. The reaction time was determined as 30, 60, 90 and 120 minutes after some preliminary experiments. After the synthesis, the crystal structure and the morphology of the products were examined by X-Ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). As a result, the forms of Zinc Oxide Borate Hydrate [Zn3B6O12.3.5H2O], Admontite [MgO(B2O3)3.7(H2O)] and Mcallisterite [Mg2(B6O7(OH)6)2.9(H2O)] were synthesized.
Keywords: Magnesium borate, zinc borate, XRD, FT-IR.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28202019 Reduction of MMP Using Oleophilic Chemicals
Authors: C. L. Voon, M. Awang
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CO2 miscible displacement is not feasible in many oil fields due to high reservoir temperature as higher pressure is required to achieve miscibility. The miscibility pressure is far higher than the formation fracture pressure making it impossible to have CO2 miscible displacement. However, by using oleophilic chemicals, minimum miscibility pressure (MMP) could be lowered. The main objective of this research is to find the best oleophilic chemical in MMP reduction using slim-tube test and Vanishing Interfacial Tension (VIT) The chemicals are selected based on the characteristics that it must be oil soluble, low water solubility, have 4 – 8 carbons, semi polar, economical, and safe for human operation. The families of chemicals chosen are carboxylic acid, alcohol, and ketone. The whole experiment would be conducted at 100°C and the best chemical is said to be effective when it is able to lower CO2-crude oil MMP the most. Findings of this research would have great impact to the oil and gas industry in reduction of operation cost for CO2EOR which is applicable to both onshore and offshore operation.
Keywords: Enhanced Oil Recovery, Oleophilic Chemical, Minimum Miscibility Pressure, CO2 Miscible Displacement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 24612018 Numerical Evaluation of Nusselt Number on the Hot Wall in Square Enclosure Filled with Nanofluid
Authors: A. Ghafouri, A. Falavand Jozaei, M. Salari
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In this paper, effects of using Alumina-water nanofluid on the rate of heat transfer have been investigated numerically. Physical model is a square enclosure with insulated top and bottom horizontal walls, while the vertical walls are kept at different constant temperatures. Two appropriate models are used to evaluate the viscosity and thermal conductivity of nanofluid. The governing stream-vorticity equations are solved using a second order central finite difference scheme, coupled to the conservation of mass and energy. The study has been carried out for the Richardson number 0.1 to 10 and the solid volume fraction 0 to 0.04. Results are presented by isotherms lines, average Nusselt number and normalized Nusselt number in different range of φ and Ri for forced, combined and natural convection dominated regime. It is found that higher heat transfer rate is predicted when the effects of nanoparticle is taken into account.
Keywords: Nanofluid, Heat Transfer Enhancement, Square Enclosure, Nusselt number.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23362017 Construction Technology of Modified Vacuum Pre-Loading Method for Slurry Dredged Soil
Authors: Ali H. Mahfouz, Gao Ming-Jun, Mohamad Sharif
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Slurry dredged soil at coastal area has a high water content, poor permeability, and low surface intensity. Hence, it is infeasible to use vacuum preloading method to treat this type of soil foundation. For the special case of super soft ground, a floating bridge is first constructed on muddy soil and used as a service road and platform for implementing the modified vacuum preloading method. The modified technique of vacuum preloading and its construction process for the super soft soil foundation improvement is then studied. Application of modified vacuum preloading method shows that the technology and its construction process are highly suitable for improving the super soft soil foundation in coastal areas.
Keywords: Super soft foundation, dredger fill, vacuum preloading, foundation treatment, construction technology.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19222016 Effect of Pretreatment Method on the Content of Phenolic Compounds, Vitamin C and Antioxidant Activity of Dried Dill
Authors: Ruta Galoburda, Zanda Kruma, Karina Ruse
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Dill contains range of phytochemicals, such as vitamin C and polyphenols, which significantly contribute to their total antioxidant activity. The aim of the current research was to determine the best blanching method for processing of dill prior to microwave vacuum drying based on the content of phenolic compounds, vitamin C and free radical scavenging activity. Two blanching mediums were used – water and steam, and for part of the samples microwave pretreatment was additionally used. Evaluation of vitamin C, phenolic contents and scavenging of DPPH˙ radical in dried dill was performed. Blanching had an effect on all tested parameters and the blanching conditions are very important. After evaluation of the results, as the best method for dill pretreatment was established blanching at 90 °C for 30 seconds.
Keywords: blanching, microwave vacuum drying, TPC, vitamin C.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 31042015 Influence of Plastic Waste Reinforcement on Compaction and Consolidation Behavior of Silty Soil
Authors: Maryam Meftahi, Yashar Hamidzadeh
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In recent decades, the amount of solid waste production has been rising. In the meantime, plastic waste is one of the major parts of urban solid waste, so, recycling plastic waste from water bottles has become a serious challenge in the whole world. The experimental program includes the study of the effect of waste plastic fibers on maximum dry density (MDD), optimum moisture content (OMC) with different sizes and contents. Also, one dimensional consolidation tests were carried out to evaluate the benefit of utilizing randomly distributed waste plastics fiber to improve the engineering behavior of a tested soils. Silty soil specimens were prepared and tested at five different percentages of plastic waste content (i.e. 0.25%, 0.50%, 0.75%, 1% and 1.25% by weight of the parent soil). The size of plastic chips used, are 4 mm, 8 mm and 12 mm long and 4 mm in width. The results show that with the addition of waste plastic fibers, the MDD and OMC and also the compressibility of soil decrease significantly.
Keywords: Silty soil, waste plastic, compaction, consolidation, reinforcement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7082014 DYVELOP Method Implementation for the Research Development in Small and Middle Enterprises
Authors: Jiří F. Urbánek, David Král
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Small and Middle Enterprises (SME) have a specific mission, characteristics, and behavior in global business competitive environments. They must respect policy, rules, requirements and standards in all their inherent and outer processes of supply - customer chains and networks. Paper aims and purposes are to introduce computational assistance, which enables us the using of prevailing operation system MS Office (SmartArt...) for mathematical models, using DYVELOP (Dynamic Vector Logistics of Processes) method. It is providing for SMS´s global environment the capability and profit to achieve its commitment regarding the effectiveness of the quality management system in customer requirements meeting and also the continual improvement of the organization’s and SME´s processes overall performance and efficiency, as well as its societal security via continual planning improvement. DYVELOP model´s maps - the Blazons are able mathematically - graphically express the relationships among entities, actors, and processes, including the discovering and modeling of the cycling cases and their phases. The blazons need live PowerPoint presentation for better comprehension of this paper mission – added value analysis. The crisis management of SMEs is obliged to use the cycles for successful coping of crisis situations. Several times cycling of these cases is a necessary condition for the encompassment of the both the emergency event and the mitigation of organization´s damages. Uninterrupted and continuous cycling process is a good indicator and controlling actor of SME continuity and its sustainable development advanced possibilities.Keywords: Blazons, computational assistance, DYVELOP method, small and middle enterprises.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7032013 Development of a Smart System for Measuring Strain Levels of Natural Gas and Petroleum Pipelines on Earthquake Fault Lines in Türkiye
Authors: Ahmet Yetik, Seyit Ali Kara, Cevat Özarpa
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Load changes occur on natural gas and oil pipelines due to natural disasters. The displacement of the soil around the natural gas and oil pipes due to situations that may cause erosion, such as earthquakes, landslides, and floods, is the source of this load change. The exposure of natural gas and oil pipes to variable loads causes deformation, cracks, and breaks in these pipes. Such cracks and breaks can cause significant damage to people and the environment, including the risk of explosions. Especially with the examinations made after natural disasters, it can be easily understood which of the pipes has sustained more damage in those quake-affected regions. It has been determined that earthquakes in Türkiye have caused permanent damage to pipelines. This project was initiated in response to the identification of cracks and gas leaks in the insulation gaskets placed in the pipelines, especially at the junction points. In this study, a SCADA (Supervisory Control and Data Acquisition) application has been developed to monitor load changes caused by natural disasters. The developed SCADA application monitors the changes in the x, y, and z axes of the stresses occurring in the pipes with the help of strain gauge sensors placed on the pipes. For the developed SCADA system, test setups in accordance with the standards were created during the fieldwork. The test setups created were integrated into the SCADA system, and the system was followed up. Thanks to the SCADA system developed with the field application, the load changes that will occur on the natural gas and oil pipes are instantly monitored, and the accumulations that may create a load on the pipes and their surroundings are immediately intervened, and new risks that may arise are prevented. It has contributed to energy supply security, asset management, pipeline holistic management, and overall sustainability in the industry.
Keywords: Earthquake, natural gas pipes, oil pipes, voltage measurement, landslide.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1132012 Evaluating the Feasibility of Magnetic Induction to Cross an Air-Water Boundary
Authors: Mark Watson, J.-F. Bousquet, Adam Forget
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A magnetic induction based underwater communication link is evaluated using an analytical model and a custom Finite-Difference Time-Domain (FDTD) simulation tool. The analytical model is based on the Sommerfeld integral, and a full-wave simulation tool evaluates Maxwell’s equations using the FDTD method in cylindrical coordinates. The analytical model and FDTD simulation tool are then compared and used to predict the system performance for various transmitter depths and optimum frequencies of operation. To this end, the system bandwidth, signal to noise ratio, and the magnitude of the induced voltage are used to estimate the expected channel capacity. The models show that in seawater, a relatively low-power and small coils may be capable of obtaining a throughput of 40 to 300 kbps, for the case where a transmitter is at depths of 1 to 3 m and a receiver is at a height of 1 m.Keywords: Magnetic Induction, FDTD, Underwater Communication, Sommerfeld.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5692011 CFD Study of the Fluid Viscosity Variation and Effect on the Flow in a Stirred Tank
Authors: Achouri Ryma, Hatem Dhaouadi, Hatem Mhiri, Philippe Bournot
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Stirred tanks are widely used in all industrial sectors. The need for further studies of the mixing operation and its different aspects comes from the diversity of agitation tools and implemented geometries in addition to the specific characteristics of each application. Viscous fluids are often encountered in industry and they represent the majority of treated cases, as in the polymer sector, food processing, pharmaceuticals and cosmetics. That's why in this paper, we will present a three-dimensional numerical study using the software Fluent, to study the effect of varying the fluid viscosity in a stirred tank with a Rushton turbine. This viscosity variation was performed by adding carboxymethylcellulose (CMC) to the fluid (water) in the vessel. In this work, we studied first the flow generated in the tank with a Rushton turbine. Second, we studied the effect of the fluid viscosity variation on the thermodynamic quantities defining the flow. For this, three viscosities (0.9% CMC, 1.1% CMC and 1.7% CMC) were considered.
Keywords: CFD, CMC, Mixing, Viscosity, Rushton turbine.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 35292010 Determination of Seismic Wave of Consolidated Granite Rock in Penang Island: UltrasonicTesting Method Vs Seismic Refraction Method
Authors: Mohd Hafiz Musa, Zulfadhli Hasan Adli, M . N . Khairul Arifin
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In seismic survey, the information regarding the velocity of compression wave (Vp) as well as shear wave (Vs) are very useful especially during the seismic interpretation. Previous studies showed that both Vp and Vs determined by above methods are totally different with respect to each other but offered good approximation. In this study, both Vp and Vs of consolidated granite rock were studied by using ultrasonic testing method and seismic refraction method. In ultrasonic testing, two different condition of rock are used which is dry and wet. The differences between Vp and Vs getting by using ultrasonic testing and seismic refraction were investigated and studied. The effect of water content in granite rock towards the value of Vp and Vs during ultrasonic testing are also measured. Within this work, the tolerance of the differences between the velocity of seismic wave getting from ultrasonic testing and the velocity of seismic wave getting from seismic refraction are also measured and investigated.Keywords: Compressional wave, Granite, Shear Wave, Velocity
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20482009 Linear Stability Characteristics of Wake-Shear Layers in Two-Phase Shallow Flows
Authors: Inta Volodko, Valentina Koliskina
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Linear stability of wake-shear layers in two-phase shallow flows is analyzed in the present paper. Stability analysis is based on two-dimensional shallow water equations. It is assumed that the fluid contains uniformly distributed solid particles. No dynamic interaction between the carrier fluid and particles is expected in the initial moment. Linear stability curves are obtained for different values of the particle loading parameter, the velocity ratio and the velocity deficit. It is shown that the increase in the velocity ratio destabilizes the flow. The particle loading parameter has a stabilizing effect on the flow. The role of the velocity deficit is also destabilizing: the increase of the velocity deficit leads to less stable flow.Keywords: Linear stability, Shallow flows, Wake-shear flows.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12502008 Influence of Natural Gum on Curcumin Supersaturation in Gastrointestinal Fluids
Authors: Patcharawalai Jaisamut, Kamonthip Wiwattanawongsa, Ruedeekorn Wiwattanapatapee
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Supersaturation of drugs in the gastrointestinal tract is one approach to increase the absorption of poorly water-soluble drugs. The stabilization of a supersaturated state was achieved by adding precipitation inhibitors that may act through a variety of mechanisms. In this study, the effect of the natural gums, acacia, gelatin, pectin and tragacanth on curcumin supersaturation in simulated gastric fluid (SGF) (pH 1.2), fasted state simulated gastric fluid (FaSSGF) (pH 1.6), and simulated intestinal fluid (SIF) (pH 6.8) was investigated. The results indicated that all natural gums significantly increased the curcumin solubility (about 1.2-6-fold) when compared to the absence of gum, and assisted in maintaining the supersaturated drug solution. Among the tested gums, pectin at 3% w/w was the best precipitation inhibitor with a significant increase in the degree of supersaturation about 3-fold in SGF, 2.4-fold in FaSSGF and 2-fold in SIF.
Keywords: Curcumin, Solubility, Supersaturation, Precipitation inhibitor.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23182007 Developing Three-Dimensional Digital Image Correlation Method to Detect the Crack Variation at the Joint of Weld Steel Plate
Authors: Ming-Hsiang Shih, Wen-Pei Sung, Shih-Heng Tung
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The purposes of hydraulic gate are to maintain the functions of storing and draining water. It bears long-term hydraulic pressure and earthquake force and is very important for reservoir and waterpower plant. The high tensile strength of steel plate is used as constructional material of hydraulic gate. The cracks and rusts, induced by the defects of material, bad construction and seismic excitation and under water respectively, thus, the mechanics phenomena of gate with crack are probing into the cause of stress concentration, induced high crack increase rate, affect the safety and usage of hydroelectric power plant. Stress distribution analysis is a very important and essential surveying technique to analyze bi-material and singular point problems. The finite difference infinitely small element method has been demonstrated, suitable for analyzing the buckling phenomena of welding seam and steel plate with crack. Especially, this method can easily analyze the singularity of kink crack. Nevertheless, the construction form and deformation shape of some gates are three-dimensional system. Therefore, the three-dimensional Digital Image Correlation (DIC) has been developed and applied to analyze the strain variation of steel plate with crack at weld joint. The proposed Digital image correlation (DIC) technique is an only non-contact method for measuring the variation of test object. According to rapid development of digital camera, the cost of this digital image correlation technique has been reduced. Otherwise, this DIC method provides with the advantages of widely practical application of indoor test and field test without the restriction on the size of test object. Thus, the research purpose of this research is to develop and apply this technique to monitor mechanics crack variations of weld steel hydraulic gate and its conformation under action of loading. The imagines can be picked from real time monitoring process to analyze the strain change of each loading stage. The proposed 3-Dimensional digital image correlation method, developed in the study, is applied to analyze the post-buckling phenomenon and buckling tendency of welded steel plate with crack. Then, the stress intensity of 3-dimensional analysis of different materials and enhanced materials in steel plate has been analyzed in this paper. The test results show that this proposed three-dimensional DIC method can precisely detect the crack variation of welded steel plate under different loading stages. Especially, this proposed DIC method can detect and identify the crack position and the other flaws of the welded steel plate that the traditional test methods hardly detect these kind phenomena. Therefore, this proposed three-dimensional DIC method can apply to observe the mechanics phenomena of composite materials subjected to loading and operating.Keywords: Welded steel plate, crack variation, three-dimensional Digital Image Correlation (DIC).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16042006 A Framework and Case Study for Sustainable Development of Urban Areas
Authors: Yasaman Zeinali, Farid Khosravikia
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This paper presents a multi-objective framework for sustainable urban development. The proposed framework aims to address different aspects of sustainability in urban development planning. These aspects include, but are not limited to education, health, job opportunities, architecture, culture, environment, mobility, energy, water, waste, and so on. Then, the proposed framework is applied to the Brackenridge Tract (an area in downtown Austin, Texas), to redevelop that area in a sustainable way. The detail of the implementation process is presented in this paper. The ultimate goal of this paper is to develop a sustainable area in downtown Austin with ensuring that it locally meets the needs of present and future generations with respect to economic, social, environmental, health as well as cultural aspects. Moreover, it helps the city with the population growth problem by accommodating more people in that area.
Keywords: Environmental impacts of human activities, sustainability, urban planning.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12502005 The Effects of Production, Transportation and Storage Conditions on Mold Growth in Compound Feeds
Authors: N. Cetinkaya
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The objective of the present study is to determine the critical control points during the production, transportation and storage conditions of compound feeds to be used in the Hazard Analysis Critical Control Point (HACCP) feed safety management system. A total of 40 feed samples were taken after 20 and 40 days of storage periods from the 10 dairy and 10 beef cattle farms following the transportation of the compound feeds from the factory. In addition, before transporting the feeds from factory immediately after production of dairy and beef cattle compound feeds, 10 from each total 20 samples were taken as 0 day. In all feed samples, chemical composition and total aflatoxin levels were determined. The aflatoxin levels in all feed samples with the exception of 2 dairy cattle feeds were below the maximum acceptable level. With the increase in storage period in dairy feeds, the aflatoxin levels were increased to 4.96 ppb only in a BS8 dairy farm. This value is below the maximum permissible level (10 ppb) in beef cattle feed. The aflatoxin levels of dairy feed samples taken after production varied between 0.44 and 2.01 ppb. Aflatoxin levels were found to be between 0.89 and 3.01 ppb in dairy cattle feeds taken on the 20th day of storage at 10 dairy cattle farm. On the 40th day, feed aflatoxin levels in the same dairy cattle farm were found between 1.12 and 7.83 ppb. The aflatoxin levels were increased to 7.83 and 6.31 ppb in 2 dairy farms, after a storage period of 40 days. These obtained aflatoxin values are above the maximum permissible level in dairy cattle feeds. The 40 days storage in pellet form in the HACCP feed safety management system can be considered as a critical control point.
Keywords: Aflatoxin, beef cattle feed, compound feed, dairy cattle feed, HACCP.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8482004 Fatigue Properties of Steel Sheets Treated by Nitrooxidation
Authors: M. Maronek, J. Barta, P. Palcek, K. Ulrich
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Low carbon deep drawing steel DC 01 according to EN 10130-91 was nitrooxidized in dissociated ammonia at 580°C/45 min and consequently oxidised at 380°C/5 min in vapour of distilled water. Material after nitrooxidation had 54 % increase of yield point, 34 % increase of strength and 10-times increased resistance to atmospheric corrosion in comparison to the material before nitrooxidation. The microstructure of treated material consisted of thin ε-phase layer connected to layer containing precipitated massive needle shaped Fe4N - γ' nitrides. This layer passed to a diffusion layer consisting of fine irregular shaped Fe16N2 - α'' nitrides regularly dispersed in ferritic matrix. Fatigue properties were examined under bending load with frequency of 20 kHz and sinusoidal symmetric cycle. The results confirmed positive influence of nitrooxidation on fatigue properties as fatigue limit of treated material was double in comparison to untreated material.
Keywords: steel sheet, fatigue, nitrooxidation, S-N diagram
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17222003 Enhancing Agricultural Sustainability and Food Security in Somalia: Addressing Climate Change Challenges
Authors: Ahmed A. Hassan
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The agriculture industry in Somalia employs a large portion of the country's workforce. Somalia has been known for its production and notable agriculture for many years, the key sector that fuels the country's economy. Due to decades of civil conflict, poor administration, neglect, and a string of natural calamities, the Somali agricultural industry has suffered significant damage. The irrigation systems in Juba and Shabelle, the two major rivers, have failed and deteriorated. Crop output has decreased because of ongoing drought, poor agricultural techniques, desertification, and the exodus of rural people to neighboring nations. With pandemic levels of hunger and malnutrition brought on by climate change, Somalia has become one of the world's most food-insecure countries. Additionally, there is strong evidence that climate change, particularly in Somalia and other East African nations, has exacerbated civil wars across Africa. The El Nino/Southern Oscillation, which results in drier and warmer weather in tropical regions, may have contributed to numerous civil wars. Additionally, an increase in temperature is believed to raise the risk of internal armed conflict in sub-Saharan African nations. This paper examines Somalia's present extension programs, lists the challenges the nation's agricultural industry faces, and discusses the effects of climate change. Improvement measures are advised based on the analysis presented in the paper. This article's major goals are to highlight the serious challenges that Somali farmers face and to offer potential solutions for achieving sustainable agriculture and food security through the worst of climate change. Farmers, legislators, decision-makers, and academics may find the material in this article useful in developing credible plans, and policies, and in establishing research and extension programs. With improved extension systems, management, encouraging public investments, and an enabling climate, Somalia's agricultural industry can increase its resilience, the quality of life for its population, and the safety and added value of its goods. Offshore and coastal fisheries can contribute more to sector growth and return to and surpass their amazing pre-war output and export levels.
Keywords: Sustainable agriculture, innovation, land use, climate change, farm management, drought management, resilience, agri-business, agri-extension, farmer field schools, agricultural development.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 992002 Comparative Study of Experimental and Theoretical Convective, Evaporative for Two Model Distiller
Authors: Khaoula Hidouri, Ali Benhmidene, Bechir Chouachi
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The purification of brackish seawater becomes a necessity and not a choice against demographic and industrial growth especially in third world countries. Two models can be used in this work: simple solar still and simple solar still coupled with a heat pump. In this research, the productivity of water by Simple Solar Distiller (SSD) and Simple Solar Distiller Hybrid Heat Pump (SSDHP) was determined by the orientation, the use of heat pump, the simple or double glass cover. The productivity can exceed 1.2 L/m²h for the SSDHP and 0.5 L/m²h for SSD model. The result of the global efficiency is determined for two models SSD and SSDHP give respectively 30%, 50%. The internal efficiency attained 35% for SSD and 60% of the SSDHP models. Convective heat coefficient can be determined by attained 2.5 W/m²°C and 0.5 W/m²°C respectively for SSDHP and SSD models.
Keywords: Productivity, efficiency, convective heat coefficient, SSD model, SSDHP model.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 810