Search results for: long-term experiments

Authors: Arun Goel, D. V. S. Verma, Sanjeev Sangwan

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The present study was aimed to develop a discharge measuring device for irrigation and laboratory channels. Experiments were conducted on a sharp edged constricted flow meters having four types of width constrictions namely 2:1, 1.5:1, 1:1, and 90o in the direction of flow. These devices were made of MS sheets and installed separately in a rectangular flume. All these four devices were tested under free and submerged flow conditions. Eight different discharges varying from 2 lit/sec to 30 lit/sec were passed through each device. In total around 500 observations of upstream and downstream depths were taken in the present work. For each discharge, free submerged and critical submergence under different flow conditions were noted and plotted. Once the upstream and downstream depths of flow over any of the device are known, the discharge can be easily calculated with the help of the curves developed for free and submerged flow conditions. The device having contraction 2:1 is the most efficient one as it allows maximum critical submergence.

Keywords: flowrate, flowmeter, open channels, submergence

Procedia PDF Downloads 433

Authors: Samir Khene

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Present and future industrial uses of high critical temperature superconductors require high critical temperatures TC and strong current densities JC. These two aims constitute the two motivations of the scientific research in this domain. The most significant feature of any superconductor, from the viewpoint of uses, is the maximum electrical transport current density that this superconductor is capable of withstanding without loss of energy. In this work, vortices pinning in conventional and high-TC superconductors will be studied. Our experiments on vortices pinning in single crystals and nanoparticles of YBa2Cu3O7- and La1.85 Sr0.15CuO will be presented. It will be given special attention to the study of the YBa2Cu3O7- nanoparticles doped by ferromagnetic nanoparticles of Y3Fe5O12. The ferromagnetism and superconductivity coexistence in this compound will be demonstrated, and the influence of these ferromagnetic nanoparticles on the variations of the critical current density JC in YBa2Cu3O7- nanoparticles as a function of applied field H and temperature T will be studied.

Keywords: ferromagnetism, superconductivity, coexistence, magnetic material

Procedia PDF Downloads 79

Authors: A. Gharaei, R. Karami

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Rutilus frisii Kutum was exposed to various concentrations of mercuric chloride in water to determine its acute toxicity and bioaccumulation. We carried out ten treatments with three replicates and one control for each of the chemicals using the static O. E. C. D. method in 55-liter-tanks each containing 14 fingerlings. During the experiments, the average pH was recorded as 7.8, total hardness was measured to be 255 mg/l, the average water temperature was 27±1 degrees centigrade and dissolved oxygen was 7.2 mg/l. Mean LC50 values of Hgcl2 for juvenile R. frisii kutum with mean weight 1±0.2 gr were 0.102 and 0.86 mgHg/l at 24h and 96h, respectively. The bioaccumulation values during 24h in tissue, kidney, and gill were 1.55, 16.1, and 22.7 mgHg/l, respectively. So, these values during 96h were 2.8, 16.8, and 26.65 mgHg/l, respectively. The bioconcentration factors in tissue, kidney, and gill during 24h were 14.75, 153.39, and 216.11 and so during 96h were 33.8, 198.1, and 313.5 times. These results show that bioaccumulation was highest in the gill and then kidney and tissue, respectively. This study suggested that between mercury concentrations of water with bioaccumulation in tissue more than kidney and gill.

Keywords: HgCl2, LC5096h, bioaccumulation, Rutilus frisii Kutum, Caspian Sea

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Authors: Matloub Hussaina

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This paper investigates the impact of information sharing and capacity constraints on backlog bullwhip effect of Automatic Pipe Line Inventory and Order Based Production Control System (APIOBPCS). System dynamic simulation using iThink Software has been applied. It has been found that smooth ordering by Tier 1 can be achieved when Tier 1 has medium capacity constraints. Simulation experiments also show that information sharing helps to reduce 50% of backlog bullwhip effect in capacitated supply chains. This knowledge is of value per se, giving supply chain operations managers and designers a practical way in to controlling the backlog bullwhip effect. Future work should investigate the total cost implications of capacity constraints and safety stocks in multi-echelon supply chain.

Keywords: supply chain dynamics, information sharing, capacity constraints, simulation, APIOBPCS

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Authors: Meriam Khelifa

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In recent years, many studies have focused on the harvesting of the vibrations energy to produce electrical energy using contact separation (CS) triboelectric nanogenerators (TENG). The simplest design for a TENG consists of a capacitor comprising a single moving electrode. The conversion efficiency of vibration energy into electrical energy can, in principle, reach 100%. But to actually achieve this objective, it is necessary to optimize the parameters of the TENG, such as the dielectric constant and the thickness of the insulator, the load resistance, etc. In particular, the use of a switch which is actioned at optimal times within the TENG cycle is essential. Using numerical modeling and experimental design, we applied a methodology to find the TENG parameters which optimize the energy transfer efficiency (ETE) to almost 100% for any vibration frequency and amplitude. The rather simple design of a TENG is promising as an environment friendly device. It opens the doors for harvesting acoustic vibrations from the environment and to design effective protection against environmental noise.

Keywords: vibrations, CS TENG, efficiency, design of experiments

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Authors: Jayasiler Kunasagaram

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In power generation, coal fineness is crucial to maintain flame stability, ensure combustion efficiency, and lower emissions to the environment. In order for the pulverized coal to react effectively in the boiler furnace, the size of coal particles needs to be at least 70% finer than 74 μm. This paper presents the experiment results of coal fineness, air fuel ratio and fuel weight distribution in pulverized fuel pipes at classifier vane 40%. The aim of this experiment is to extract the pulverized coal is kinetically and investigate the data accordingly. Dirty air velocity, coal sample extraction, and coal sieving experiments were performed to measure coal fineness. The experiment results show that required coal fineness can be achieved at 40 % classifier vane. However, this does not surpass the desired value by a great margin.

Keywords: coal power, emissions, isokinetic sampling, power generation

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Authors: Andrey V. Timofeev

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This paper introduces an original method for guaranteed estimation of the accuracy of an ensemble of Lipschitz classifiers. The solution was obtained as a finite closed set of alternative hypotheses, which contains an object of classification with a probability of not less than the specified value. Thus, the classification is represented by a set of hypothetical classes. In this case, the smaller the cardinality of the discrete set of hypothetical classes is, the higher is the classification accuracy. Experiments have shown that if the cardinality of the classifiers ensemble is increased then the cardinality of this set of hypothetical classes is reduced. The problem of the guaranteed estimation of the accuracy of an ensemble of Lipschitz classifiers is relevant in the multichannel classification of target events in C-OTDR monitoring systems. Results of suggested approach practical usage to accuracy control in C-OTDR monitoring systems are present.

Keywords: Lipschitz classifiers, confidence set, C-OTDR monitoring, classifiers accuracy, classifiers ensemble

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Authors: Anam Alam, Rahim Jamaluddin Kanji

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With the rapid growth of event in everywhere, event extraction has now become an important matter to retrieve the information from the unstructured data. One of the challenging problems is to extract the event from it. An event is an observable occurrence of interaction among entities. The paper investigates the effectiveness of event extraction capabilities of three software tools that are Wandora, Nitro and SPSS. We performed standard text mining techniques of these tools on the data sets of (i) Afghan War Diaries (AWD collection), (ii) MUC4 and (iii) WebKB. Information retrieval measures such as precision and recall which are computed under extensive set of experiments for Event Extraction. The experimental study analyzes the difference between events extracted by the software and human. This approach helps to construct an algorithm that will be applied for different machine learning methods.

Keywords: event extraction, Wandora, nitro, SPSS, event analysis, extraction method, AFG, Afghan War Diaries, MUC4, 4 universities, dataset, algorithm, precision, recall, evaluation

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Authors: Muazu A.

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Haphazard and inappropriate plant spacing and poor soilfertility management practice are among the major factorsconstraining onion production in Gashua, Bade Locale Government Yobe State.Field experiments were conducted in 2023 dry season ar Federal University, Gashua university farm assess the influence of intra-row spacing (2.5, 5, 7.5, 10 and 12.5 cm) and nitrogen fertilizerrate (0, 41, 82 and 123kg Nha-1) growth, bulb yield and quality of onion. The experiment was laid out in a randomized complete block design (RCBD) with three replications. The main effects of nitrogen rate and intra-row spacing influenced only the plant height stand count significantly obtained from 7.5cm and 82kg Nha-1 intra-row spacing and nitrogen fertilizer respectively. The highest yield was obtained from the application of 82kg Nha-1 and plant spacing of 5.0cm and 7.5cm respectively.

Keywords: onion, intra-row spacing, nitrogen fertilizer, yield

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Authors: Wentian Shi, Daming Shi, Maysam Orouskhani, Feng Tian

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Whereas currently the most prevalent deep learning methods require a large amount of data for training, few-shot learning tries to learn a model from limited data without extensive retraining. In this paper, we present a loss function based on triplet loss for solving few-shot problem using metric based learning. Instead of setting the margin distance in triplet loss as a constant number empirically, we propose an adaptive margin distance strategy to obtain the appropriate margin distance automatically. We implement the strategy in the deep siamese network for deep metric embedding, by utilizing an optimization approach by penalizing the worst case and rewarding the best. Our experiments on image recognition and co-segmentation model demonstrate that using our proposed triplet loss with adaptive margin distance can significantly improve the performance.

Keywords: few-shot learning, triplet network, adaptive margin, deep learning

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Authors: A. Elbatran, Y. Ahmed, A. Radwan, M. Ishak

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The use of WIG craft is representing an ambitious technology that will support in reducing time, effort, and money of the conventional marine transportation in the future. This paper investigates the aerodynamic characteristic of compound wing-in-ground effect (WIG) craft model. Drag coefficient, lift coefficient and Lift and drag ratio were studied numerically with respect to the ground clearance and the wing angle of attack. The modifications of the wing has been done in order to investigate the most suitable wing configuration that can increase the wing lift-to-drag ratio at low ground clearance. A numerical investigation was carried out in this research work using finite volume Reynolds-Averaged Navier-Stokes Equations (RANSE) code ANSYS CFX, Validation was carried out by using experiments. The experimental and the numerical results concluded that the lift to drag ratio decreased with the increasing of the ground clearance.

Keywords: drag Coefficient, ground clearance, navier-stokes, WIG

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Authors: Anuta Mukherjee, Saswati Mukherjee

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Data is growing everyday. Social networking sites such as Twitter are becoming an integral part of our daily lives, contributing a large increase in the growth of data. It is a rich source especially for sentiment detection or mining since people often express honest opinion through tweets. However, although sentiment analysis is a well-researched topic in text, this analysis using Twitter data poses additional challenges since these are unstructured data with abbreviations and without a strict grammatical correctness. We have employed collision theory to achieve sentiment analysis in Twitter data. We have also incorporated discourse analysis in the collision theory based model to detect accurate sentiment from tweets. We have also used the retweet field to assign weights to certain tweets and obtained the overall weightage of a topic provided in the form of a query. Hadoop has been exploited for speed. Our experiments show effective results.

Keywords: sentiment analysis, twitter, collision theory, discourse analysis

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Authors: Sercan Basit, Muhlis N. Sarıdede

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Metal amounts of copper based compounds in the various wastes have been recovered successfully by hydrometallurgical treatment methods in the literature. X-ray diffraction pattern of the brass melting slag demonstrates that it contains sufficient amount of recoverable copper. Recovery of copper from brass melting dross by sulfuric acid leaching and the effect of temperature and acid and oxidant concentration on recovery rate of copper have been investigated in this study. Experiments were performed in a temperature-controlled reactor in sulfuric acid solution in different molarities using solid liquid ratio of 100 g/L, with leaching time of 300 min. Temperature was changed between 25 °C and 80 °C and molarity was between 0.5 and 3M. The results obtained showed that temperature has important positive effect on recovery whereas it decreases with time. Also copper was recovered in larger amounts from brass dross in the presence of H2O2 as an oxidant according to the case that oxidant was not used.

Keywords: brass dross, copper recovery, hydrogen peroxide, leaching

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Authors: Mohsen Marani Barzani, Ahmed A. D. Sarhan, Saeed Farahany, Ramesh Singh

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Surface roughness and chip morphology are important output in manufacturing product. In this paper, an experimental investigation was conducted to determine the effects of various cutting speeds and feed rates on surface roughness and chip morphology in turning the Al-Si cast alloy and Sr-containing. Experimental trials carried out using coated carbide inserts. Experiments accomplished under oblique dry cutting when various cutting speeds 70, 130 and 250 m/min and feed rates of 0.05, 0.1 and 0.15 mm/rev were used, whereas depth of cut kept constant at 0.05 mm. The results showed that Sr-containing Al-Si alloy have poor surface roughness in comparison to Al-Si alloy (base alloy). The surface roughness values reduce with cutting speed increment from 70 to 250 m/min. the size of chip changed with changing silicon shape in Al matrix. Also, the surface finish deteriorated with increase in feed rate from 0.5 mm/rev to 0.15 mm/rev.

Keywords: strontium, surface roughness, chip, morphology, turning

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Authors: Ulas Vural, M. Ergun Okay, E. Mesut Yildiz

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Telecommunication service providers demand accurate and precise prediction of customer churn probabilities to increase the effectiveness of their customer relation services. The large amount of customer data owned by the service providers is suitable for analysis by machine learning methods. In this study, expenditure data of customers are analyzed by using an artificial neural network (ANN). The ANN model is applied to the data of customers with different billing duration. The proposed model successfully predicts the churn probabilities at 83% accuracy for only three months expenditure data and the prediction accuracy increases up to 89% when the nine month data is used. The experiments also show that the accuracy of ANN model increases on an extended feature set with information of the changes on the bill amounts.

Keywords: customer relationship management, churn prediction, telecom industry, deep learning, artificial neural networks

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Authors: Trung Le Thanh

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Soil permeability coefficient is an important parameter that affects the effectiveness of mortar restoration work to reinforce soft soil. Currently, there are many methods to determine the permeability coefficient of ground through laboratory and field experiments. However, the value of the permeability coefficient is determined very differently depending on the geology in general and the sand base in particular. This article presents how to determine the permeability coefficient of sand foundation in Phu My Ward, Tan Uyen City, Binh Duong. The author analyzes and evaluates the advantages and disadvantages of assessment methods based on the data and results obtained, and on that basis recommends a suitable method for determining the permeability coefficient for sand foundations. The research results serve the evaluation of the effectiveness of grouting to reinforce soft ground in general, and grouting of bored piles in particular.

Keywords: permeability coefficient, soft soil, shaft grouting, post grouting, jet grouting

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Authors: Yinan Zhou

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One in four people in the world still lack access to clean drinking water, and there is a current lack of cost-effective ways for water-scarce regions to access it. This study seeks to investigate the solutions to water filtration in rural China as well as test the feasibility of using angiosperms as xylem candidates. Four angiosperms that are found in China and around Asia were subject to three tests to test their filtration capacity: ink water filtration, creek water filtration, and microparticle filtration. Analysis of the experiments demonstrated that Celtis Sinensis was able to produce one of the clearest solutions, filter out large debris and bacteria, and reject microparticles almost completely. Celtis Sinensis proves that angiosperm xylem filters are also competent filter candidates and, due to their availability in China, can be used as a nearby source of water filtration. Further research should be done on scaling production to a larger scale and also on the filtration of viruses.

Keywords: xylem filter, water quality, China, angiosperms, bacteria

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Authors: Adeep Hande, Shubham Agarwal

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This paper presents a study on identifying sexism in online texts using various state-of-the-art deep learning models based on BERT. We experimented with different feature sets and model architectures and evaluated their performance using precision, recall, F1 score, and accuracy metrics. We also explored the use of pseudolabeling technique to improve model performance. Our experiments show that the best-performing models were based on BERT, and their multilingual model achieved an F1 score of 0.83. Furthermore, the use of pseudolabeling significantly improved the performance of the BERT-based models, with the best results achieved using the pseudolabeling technique. Our findings suggest that BERT-based models with pseudolabeling hold great promise for identifying sexism in online texts with high accuracy.

Keywords: large language models, semi-supervised learning, sexism detection, data sparsity

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Authors: Nandy Putra, Atrialdipa Duanovsah, Kristofer Haliansyah

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The aim of this research is to design a LHP with low thermal resistance and low condenser temperature. A Self-designed cascade LHP was tested by using biomaterial, sintered copper powder, and aluminum screen mesh as the wick. Using pure water as the working fluid for the first level of the LHP and 96% alcohol as the working fluid for the second level of LHP, the experiments were run with 10W, 20W, and 30W heat input. Experimental result shows that the usage of biomaterial as wick could reduce more temperature at evaporator than by using sintered copper powder and screen mesh up to 22.63% and 37.41% respectively. The lowest thermal resistance occurred during the usage of biomaterial as wick of heat pipe, which is 2.06 ^oC/W. The usage of cascade system could be applied to LHP to reduce the temperature at condenser and reduced thermal resistance up to 17.6%.

Keywords: biomaterial, cascade loop heat pipe, screen mesh, sintered Cu

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Authors: Ujjal Chattaraj, Pbharat Saikumar, Thinley Dorji

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Earth is going to be a planet where no further life can sustain if people continue to pollute the environment. We need energy and fuels everyday for heating and lighting purposes in our life. It’s high time we know this problem and take measures at-least to reduce pollution and take alternative measures for everyday livelihood. Biogas is one of them. It is very essential to define and control the parameters for optimization of biogas production. Biogas plants can be made of different size, but it is very vital to make a biogas which will be cost effective, with greater efficiency (more production) and biogas plants that will sustain for a longer period of time for usage. In this research, experiments were carried out only on cow dung and Chicken manure depending on the substrates people out there (Bhutan) used. The experiment was done within 25 days and was tested for different temperatures and found out which produce more amount. Moreover, it was also statistically tested for their dependency and non-dependency which gave clear idea more on their production.

Keywords: digester, mesophilic temperature, organic manure, statistical analysis, thermophilic temperature, t-test

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Authors: Boukary Lam, Sebastien Deon, Patrick Fievet, Nadia Crini, Gregorio Crini

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Treatment of heavy metal-contaminated industrial wastewater has become a major challenge over the last decades. Conventional processes for the treatment of metal-containing effluents do not always simultaneously satisfy both legislative and economic criteria. In this context, coupling of processes can then be a promising alternative to the conventional approaches used by industry. The polymer-assisted ultrafiltration (PAUF) process is one of these coupling processes. Its principle is based on a sequence of steps with reaction (e.g., complexation) between metal ions and a polymer and a step involving the rejection of the formed species by means of a UF membrane. Unlike free ions, which can cross the UF membrane due to their small size, the polymer/ion species, the size of which is larger than pore size, are rejected. The PAUF process was deeply investigated herein in the case of removal of nickel ions by adding chitosan and carboxymethyl cellulose (CMC). Experiments were conducted with synthetic solutions containing 1 to 100 ppm of nickel ions with or without the presence of NaCl (0.05 to 0.2 M), and an industrial discharge water (containing several metal ions) with and without polymer. Chitosan with a molecular weight of 1.8×105 g mol⁻¹ and a degree of acetylation close to 15% was used. CMC with a degree of substitution of 0.7 and a molecular weight of 9×105 g mol⁻¹ was employed. Filtration experiments were performed under cross-flow conditions with a filtration cell equipped with a polyamide thin film composite flat-sheet membrane (3.5 kDa). Without the step of polymer addition, it was found that nickel rejection decreases from 80 to 0% with increasing metal ion concentration and salt concentration. This behavior agrees qualitatively with the Donnan exclusion principle: the increase in the electrolyte concentration screens the electrostatic interaction between ions and the membrane fixed the charge, which decreases their rejection. It was shown that addition of a sufficient amount of polymer (greater than 10⁻² M of monomer unit) can offset this decrease and allow good metal removal. However, the permeation flux was found to be somewhat reduced due to the increase in osmotic pressure and viscosity. It was also highlighted that the increase in pH (from 3 to 9) has a strong influence on removal performances: the higher pH value, the better removal performance. The two polymers have shown similar performance enhancement at natural pH. However, chitosan has proved more efficient in slightly basic conditions (above its pKa) whereas CMC has demonstrated very weak rejection performances when pH is below its pKa. In terms of metal rejection, chitosan is thus probably the better option for basic or strongly acid (pH < 4) conditions. Nevertheless, CMC should probably be preferred to chitosan in natural conditions (5 < pH < 8) since its impact on the permeation flux is less significant. Finally, ultrafiltration of an industrial discharge water has shown that the increase in metal ion rejection induced by the polymer addition is very low due to the competing phenomenon between the various ions present in the complex mixture.

Keywords: carboxymethyl cellulose, chitosan, heavy metals, nickel ion, polymer-assisted ultrafiltration

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Authors: İbrahim Hakkı Erkan, Özcan Tan

Abstract:

The performance of jet grout columns was affected by many controlled and uncontrolled parameters. The leading parameters for the controlled ones can be listed as injection pressure, rod pulling speed, rod rotation speed, number of nozzles, nozzle diameter and Water/Cement ratio. And the uncontrolled parameters are soil type, soil structure, soil layering condition, underground water level, the changes in strength parameters and the rheologic properties of cement in time. In this study, the performance of jet grout columns and the effects of pulling speed and rotation speed were investigated experimentally. For this purpose, a laboratory type jet grouting system was designed for the experiments. Through this system, jet grout columns were produced in three different conditions. The results of the study showed that the grout pressure and the lifting speed significantly affect the performance of the jet grouting columns.

Keywords: jet grout, sandy soils, soil improvement, soilcreate

Procedia PDF Downloads 251

Authors: Michael R. Phangtriastu, Herriyandi Herriyandi, Diaz D. Santika

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This paper presents a comparison of the implementation of metaheuristic algorithms to train the antecedent parameters and consequence parameters in the adaptive network-based fuzzy inference system (ANFIS). The algorithms compared are genetic algorithm (GA), particle swarm optimization (PSO), and artificial bee colony (ABC). The objective of this paper is to benchmark well-known metaheuristic algorithms. The algorithms are applied to several data set with different nature. The combinations of the algorithms' parameters are tested. In all algorithms, a different number of populations are tested. In PSO, combinations of velocity are tested. In ABC, a different number of limit abandonment are tested. Experiments find out that ABC is more reliable than other algorithms, ABC manages to get better mean square error (MSE) than other algorithms in all data set.

Keywords: ANFIS, artificial bee colony, genetic algorithm, metaheuristic algorithm, particle swarm optimization

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Authors: Zhipeng Chen, Lingfeng Wang, Shuang Qiu, Shijian Ge

Abstract:

Macroalgae are larger in size compared with microalgae; hence, they imposed lower separation and drying costs. To explore the potential for enhancing cultivation conditions in macroalgae Chaetomorpha linum (C. linum)-based bioreactor for nutrient recovery from municipal wastewaters and examine the biochemical composition of the macroalgae for the potential downstream production of biofuels, screening experiments were performed. This study suggested that C. linum grew well on primary (PW), secondary (SW), and centrate wastewater (CW). A step feeding approach was shown to significantly enhance biomass productivity when grown on 10% CW; meanwhile, nitrogen and phosphorus removal efficiencies increased to 86.8 ± 1.1% and 92.6 ± 0.2%, respectively. The CO₂-supplemented SW cultures were 1.20 times more productive than the corresponding controls without CO₂ supplementation. These findings demonstrate that C. linum could represent a promising and efficient wastewater treatment alternative which could also provide a feedstock for downstream processing to biofuels.

Keywords: biofuel production, macroalgae, nutrient removal, wastewater

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Authors: Xuan Sun, Mingbo Tong

Abstract:

To understand the factors which affect impact damage on composite structures, particularly the effects of impact position and ribs. In this paper, a finite element model (FEM) of low-velocity impact damage on the composite structure was established via the nonlinear finite element method, combined with the user-defined materials subroutine (VUMAT) of the ABAQUS software. The structural elements chosen for the investigation comprised a series of stiffened composite panels, representative of real aircraft structure. By impacting the panels at different positions relative to the ribs, the effect of relative position of ribs was found out. Then the simulation results and the experiments data were compared. Finally, the factors which affect impact damage on the structures were discussed. The paper was helpful for the design of stiffened composite structures.

Keywords: stiffened, low-velocity impact, Abaqus, impact energy

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Authors: Elnaz Akbari, Zolkafle Buntat

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Today, the use of carbon-based materials such as graphene, carbon nanotubes, etc. in various applications is being extensively studied by researchers in the field. One of such applications is using them in gas sensors. While analytical investigations on the physical and chemical properties of carbon nanomaterials are the focal points in the studies, the need for experimental measurements on various physical characteristics of these materials is deeply felt. In this work, a set of experiments has been conducted using arc discharge Methane decomposition attempting to obtain carbonaceous materials (C-strands) formed between graphite electrodes. The current-voltage (I-V) characteristics of the fabricated C-strands have been investigated in the presence and absence of two different gases, NO2 and CO2. The results reveal that the current passing through the carbon films increases when the concentrations of gases are increased from 200 to 800 ppm. This phenomenon is a result of conductance changes and can be employed in sensing applications such as gas sensors.

Keywords: carbonaceous materials, gas sensing, methane arc discharge decomposition, I-V characteristics

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Authors: T. J. Jemi Jeya, V. Sriram

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Pile Supported Caisson breakwater is an ecofriendly breakwater very useful in coastal zone protection. The model is developed by considering the advantages of both caisson breakwater and pile supported breakwater, where the top portion is a vertical or quarter circle caisson and the bottom portion consists of a pile supported breakwater defined as Vertical Pile Supported Breakwater (VPSCB) and Quarter-circle Pile Supported Breakwater (QPSCB). The study mainly focuses on comparison of run up over VPSCB and QPSCB under oblique waves. The experiments are carried out in a shallow wave basin under different water depths (d = 0.5 m & 0.55 m) and under different oblique regular waves (0⁰, 15⁰, 30⁰). The run up over the surface is measured by placing two run up probes over the surface at 0.3 m on both sides from the centre of the model. The results show that the non-dimensional shoreward run up shows slight decrease with respect to increase in angle of wave attack.

Keywords: Caisson breakwater, pile supported breakwater, quarter circle breakwater, vertical breakwater

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Authors: Nougrara Zineb

Abstract:

The unique structure of the blood vessels in the retina has been used for biometric identification. The retina blood vessel pattern is a unique pattern in each individual and it is almost impossible to forge that pattern in a false individual. The retina biometrics’ advantages include high distinctiveness, universality, and stability overtime of the blood vessel pattern. Once the creases have been extracted from the images, a registration stage is necessary, since the position of the retinal vessel structure could change between acquisitions due to the movements of the eye. Image registration consists of following steps: Feature detection, feature matching, transform model estimation and image resembling and transformation. In this paper, we present an algorithm of registration; it is based on the characterization of retinal feature points. For experiments, retinal images from the DRIVE database have been tested. The proposed methodology achieves good results for registration in general.

Keywords: fovea, optic disc, registration, retinal images

Procedia PDF Downloads 267

Authors: M. M. Fercan, A. S. Kipcak, O. Dere Ozdemir, M. B. Piskin, E. Moroydor Derun

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Coffee is a widely consumed beverage with many components such as caffeine, flavonoids, phenolic compounds, and minerals. Coffee consumption continues to increase due to its physiological effects, its pleasant taste, and aroma. Robusta and Arabica are two basic types of coffee beans. The coffee bean used for Turkish coffee is Arabica. There are many elements in the structure of coffee and have various effect on human health such as Sodium (Na), Boron (B), Magnesium (Mg) and Iron (Fe). In this study, the amounts of Mg, Na, Fe, and B contents in Turkish coffee are determined and effect of sugar addition is investigated for conscious consumption. The analysis of the contents of coffees was determined by using inductively coupled plasma optical emission spectrometry (ICP-OES). From the results of the experiments the Mg, Na, Fe and B contents of Turkish coffee after sugar addition were found as 19.83, 1.04, 0.02, 0.21 ppm, while without using sugar these concentrations were found 21.46, 0.81, 0.008 and 0.16 ppm. In addition, element contents were calculated for 1, 3 and 5 cups of coffee in order to investigate the health effects.

Keywords: health effect, ICP-OES, sugar, Turkish coffee

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Authors: Ines Raies, Eric Kohler, Marc Fleury, Béatrice Ledésert

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In this work, the impact of clay minerals on the formation damage of sandstone reservoirs is studied to provide a better understanding of the problem of deep geothermal reservoir permeability reduction due to fine particle dispersion and migration. In some situations, despite the presence of filters in the geothermal loop at the surface, particles smaller than the filter size (<1 µm) may surprisingly generate significant permeability reduction affecting in the long term the overall performance of the geothermal system. Our study is carried out on cores from a Triassic reservoir in the Paris Basin (Feigneux, 60 km Northeast of Paris). Our goal is to first identify the clays responsible for clogging, a mineralogical characterization of these natural samples was carried out by coupling X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The results show that the studied stratigraphic interval contains mostly illite and chlorite particles. Moreover, the spatial arrangement of the clays in the rocks as well as the morphology and size of the particles, suggest that illite is more easily mobilized than chlorite by the flow in the pore network. Thus, based on these results, illite particles were prepared and used in core flooding in order to better understand the factors leading to the aggregation and deposition of this type of clay particles in geothermal reservoirs under various physicochemical and hydrodynamic conditions. First, the stability of illite suspensions under geothermal conditions has been investigated using different characterization techniques, including Dynamic Light Scattering (DLS) and Scanning Transmission Electron Microscopy (STEM). Various parameters such as the hydrodynamic radius (around 100 nm), the morphology and surface area of aggregates were measured. Then, core-flooding experiments were carried out using sand columns to mimic the permeability decline due to the injection of illite-containing fluids in sandstone reservoirs. In particular, the effects of ionic strength, temperature, particle concentration and flow rate of the injected fluid were investigated. When the ionic strength increases, a permeability decline of more than a factor of 2 could be observed for pore velocities representative of in-situ conditions. Further details of the retention of particles in the columns were obtained from Magnetic Resonance Imaging and X-ray Tomography techniques, showing that the particle deposition is nonuniform along the column. It is clearly shown that very fine particles as small as 100 nm can generate significant permeability reduction under specific conditions in high permeability porous media representative of the Triassic reservoirs of the Paris basin. These retention mechanisms are explained in the general framework of the DLVO theory

Keywords: geothermal energy, reinjection, clays, colloids, retention, porosity, permeability decline, clogging, characterization, XRD, SEM-EDS, STEM, DLS, NMR, core flooding experiments

Procedia PDF Downloads 178