Search results for: experimental determinations
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7185

Search results for: experimental determinations

1545 Biomechanical Performance of the Synovial Capsule of the Glenohumeral Joint with a BANKART Lesion through Finite Element Analysis

Authors: Duvert A. Puentes T., Javier A. Maldonado E., Ivan Quintero., Diego F. Villegas

Abstract:

Mechanical Computation is a great tool to study the performance of complex models. An example of it is the study of the human body structure. This paper took advantage of different types of software to make a 3D model of the glenohumeral joint and apply a finite element analysis. The main objective was to study the change in the biomechanical properties of the joint when it presents an injury. Specifically, a BANKART lesion, which consists in the detachment of the anteroinferior labrum from the glenoid. Stress and strain distribution of the soft tissues were the focus of this study. First, a 3D model was made of a joint without any pathology, as a control sample, using segmentation software for the bones with the support of medical imagery and a cadaveric model to represent the soft tissue. The joint was built to simulate a compression and external rotation test using CAD to prepare the model in the adequate position. When the healthy model was finished, it was submitted to a finite element analysis and the results were validated with experimental model data. With the validated model, it was sensitized to obtain the best mesh measurement. Finally, the geometry of the 3D model was changed to imitate a BANKART lesion. Then, the contact zone of the glenoid with the labrum was slightly separated simulating a tissue detachment. With this new geometry, the finite element analysis was applied again, and the results were compared with the control sample created initially. With the data gathered, this study can be used to improve understanding of the labrum tears. Nevertheless, it is important to remember that the computational analysis are approximations and the initial data was taken from an in vitro assay.

Keywords: biomechanics, computational model, finite elements, glenohumeral joint, bankart lesion, labrum

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1544 An Efficient Approach for Shear Behavior Definition of Plant Stalk

Authors: M. R. Kamandar, J. Massah

Abstract:

The information of the impact cutting behavior of plants stalk plays an important role in the design and fabrication of plants cutting equipment. It is difficult to investigate a theoretical method for defining cutting properties of plants stalks because the cutting process is complex. Thus, it is necessary to set up an experimental approach to determine cutting parameters for a single stalk. To measure the shear force, shear energy and shear strength of plant stalk, a special impact cutting tester was fabricated. It was similar to an Izod impact cutting tester for metals but a cutting blade and data acquisition system were attached to the end of pendulum's arm. The apparatus was included four strain gages and a digital indicator to show the real-time cutting force of plant stalk. To measure the shear force and also testing the apparatus, two plants’ stalks, like buxus and privet, were selected. The samples (buxus and privet stalks) were cut under impact cutting process at four loading rates 1, 2, 3 and 4 m.s-1 and three internodes fifth, tenth and fifteenth by the apparatus. At buxus cutting analysis: the minimum value of cutting energy was obtained at fifth internode and loading rate 4 m.s-1 and the maximum value of shear energy was obtained at fifteenth internode and loading rate 1 m.s-1. At privet cutting analysis: the minimum value of shear consumption energy was obtained at fifth internode and loading rate: 4 m.s-1 and the maximum value of shear energy was obtained at fifteenth internode and loading rate: 1 m.s-1. The statistical analysis at both plants showed that the increase of impact cutting speed would decrease the shear consumption energy and shear strength. In two scenarios, the results showed that with increase the cutting speed, shear force would decrease.

Keywords: Buxus, Privet, impact cutting, shear energy

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1543 Performance Evaluation of Solid Lubricant Characteristics at Different Sliding Conditions

Authors: Suresh Kumar Reddy Narala, Rakesh Kumar Gunda

Abstract:

In modern industry, mechanical parts are subjected to friction and wear, leading to heat generation, which affects the reliability, life and power consumption of machinery. To overcome the tribological losses due to friction and wear, a significant portion of lubricant with high viscous properties allows very smooth relative motion between two sliding surfaces. Advancement in modern tribology has facilitated the use of applying solid lubricants in various industrial applications. Solid lubricant additives with high viscous thin film formation between the sliding surfaces can adequately wet and adhere to a work surface. In the present investigation, an attempt has been made to investigate and evaluate the tribological studies of various solid lubricants like MoS¬2, graphite, and boric acid at different sliding conditions. The base oil used in this study was SAE 40 oil with a viscosity of 220 cSt at 400C. The tribological properties were measured on pin-on-disc tribometer. An experimental set-up has been developed for effective supply of solid lubricants to the pin-disc interface zone. The results obtained from the experiments show that the friction coefficient increases with increase in applied load for all the considered environments. The tribological properties with MoS2 solid lubricant exhibit larger load carrying capacity than that of graphite and boric acid. The present research work also contributes to the understanding of the behavior of film thickness distribution of solid lubricant using potential contact technique under different sliding conditions. The results presented in this research work are expected to form a scientific basis for selecting the best solid lubricant in various industrial applications for possible minimization of friction and wear.

Keywords: friction, wear, temperature, solid lubricant

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1542 Effect of Addition Cinnamon Extract (Cinnamomum burmannii) to Water Content, pH Value, Total Lactid Acid Bacteria Colonies, Antioxidant Activity and Cholesterol Levels of Goat Milk Yoghurt Isolates Dadih (Pediococcus pentosaceus)

Authors: Endang Purwati, Ely Vebriyanti, R. Puji Hartini, Hendri Purwanto

Abstract:

This study aimed to determine the effect of addition cinnamon extract (Cinnamomum burmannii) in making goat milk yogurt product isolates dadih (Pediococcus pentosaceus) to antioxidant activity and cholesterol levels. The method of research was the experimental method by using a Randomized Block Design (RBD), which consists of 5 treatments with 4 groups as replication. Treatment in this study was used of cinnamon extract as A (0%), B (1%), C (2%), D (3%), E (4%) in a goat’s milk yoghurt. This study was used 4200 ml of Peranakan Etawa goat’s milk and 80 ml of cinnamon extract. The variable analyzed were water content, pH value, total lactic acid bacterial colonies, antioxidant activity and cholesterol levels. The average water content ranged from 81.2-85.56%. Mean pH values rang between 4.74–4.30. Mean total lactic acid bacteria colonies ranged from 3.87 x 10⁸ - 7.95 x 10⁸ CFU/ml. The average of the antioxidant activity ranged between 10.98%-27.88%. Average of cholesterol levels ranged from 14.0 mg/ml–17.5 mg/ml. The results showed that the addition of cinnamon extract in making goat milk yoghurt product isolates dadih (Pediococcus pentosaceus) significantly different (P < 0.05) to water content, pH value, total lactic acid bacterial colonies, antioxidant activity and cholesterol levels. In conclusion, the study shows that using of cinnamon extract 4% is the best in making goat milk yoghurt.

Keywords: antioxidant, cholesterol, cinnamon, Pediococcus pentosaceus, yoghurt

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1541 Analysis of Pressure Drop in a Concentrated Solar Collector with Direct Steam Production

Authors: Sara Sallam, Mohamed Taqi, Naoual Belouaggadia

Abstract:

Solar thermal power plants using parabolic trough collectors (PTC) are currently a powerful technology for generating electricity. Most of these solar power plants use thermal oils as heat transfer fluid. The latter is heated in the solar field and transfers the heat absorbed in an oil-water heat exchanger for the production of steam driving the turbines of the power plant. Currently, we are seeking to develop PTCs with direct steam generation (DSG). This process consists of circulating water under pressure in the receiver tube to generate steam directly into the solar loop. This makes it possible to reduce the investment and maintenance costs of the PTCs (the oil-water exchangers are removed) and to avoid the environmental risks associated with the use of thermal oils. The pressure drops in these systems are an important parameter to ensure their proper operation. The determination of these losses is complex because of the presence of the two phases, and most often we limit ourselves to describing them by models using empirical correlations. A comparison of these models with experimental data was performed. Our calculations focused on the evolution of the pressure of the liquid-vapor mixture along the receiver tube of a PTC-DSG for pressure values and inlet flow rates ranging respectively from 3 to 10 MPa, and from 0.4 to 0.6 kg/s. The comparison of the numerical results with experience allows us to demonstrate the validity of some models according to the pressures and the flow rates of entry in the PTC-DSG receiver tube. The analysis of these two parameters’ effects on the evolution of the pressure along the receiving tub, shows that the increase of the inlet pressure and the decrease of the flow rate lead to minimal pressure losses.

Keywords: direct steam generation, parabolic trough collectors, Ppressure drop, empirical models

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1540 Analysis of the Detachment of Water Droplets from a Porous Fibrous Surface

Authors: Ibrahim Rassoul, E-K. Si Ahmed

Abstract:

The growth, deformation, and detachment of fluid droplets adherent to solid substrates is a problem of fundamental interest with numerous practical applications. Specific interest in this proposal is the problem of a droplet on a fibrous, hydrophobic substrate subjected to body or external forces (gravity, convection). The past decade has seen tremendous advances in proton exchange membrane fuel cell (PEMFC) technology. However, there remain many challenges to bring commercially viable stationary PEMFC products to the market. PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On the one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause 'flooding' (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The aim of this work is to investigate the stability of a liquid water droplet emerging form a GDL pore, to gain fundamental insight into the instability process leading to detachment. The approach will combine analytical and numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, water droplet, gas diffusion layer, contact angle, surface tension

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1539 Experimental Investigation on Geosynthetic-Reinforced Soil Sections via California Bearing Ratio Test

Authors: S. Abdi Goudazri, R. Ziaie Moayed, A. Nazeri

Abstract:

Loose soils normally are of weak bearing capacity due to their structural nature. Being exposed to heavy traffic loads, they would fail in most cases. To tackle the aforementioned issue, geotechnical engineers have come up with different approaches; one of which is making use of geosynthetic-reinforced soil-aggregate systems. As these polymeric reinforcements have highlighted economic and environmentally-friendly features, they have become widespread in practice during the last decades. The present research investigates the efficiency of four different types of these reinforcements in increasing the bearing capacity of two-layered soil sections using a series California Bearing Ratio (CBR) test. The studied sections are comprised of a 10 cm-thick layer of no. 161 Firouzkooh sand (weak subgrade) and a 10 cm-thick layer of compacted aggregate materials (base course) classified as SP and GW according to the United Soil Classification System (USCS), respectively. The aggregate layer was compacted to the relative density (Dr) of 95% at the optimum water content (Wopt) of 6.5%. The applied reinforcements were including two kinds of geocomposites (type A and B), a geotextile, and a geogrid that were embedded at the interface of the lower and the upper layers of the soil-aggregate system. As the standard CBR mold was not appropriate in height for this study, the mold used for soaked CBR tests were utilized. To make a comparison between the results of stress-settlement behavior in the studied specimens, CBR values pertinent to the penetrations of 2.5 mm and 5 mm were considered. The obtained results demonstrated 21% and 24.5% increments in the amount of CBR value in the presence of geocomposite type A and geogrid, respectively. On the other hand, the effect of both geotextile and geocomposite type B on CBR values was generally insignificant in this research.

Keywords: geosynthetics, geogrid, geotextile, CBR test, increasing bearing capacity

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1538 Relevance of Reliability Approaches to Predict Mould Growth in Biobased Building Materials

Authors: Lucile Soudani, Hervé Illy, Rémi Bouchié

Abstract:

Mould growth in living environments has been widely reported for decades all throughout the world. A higher level of moisture in housings can lead to building degradation, chemical component emissions from construction materials as well as enhancing mould growth within the envelope elements or on the internal surfaces. Moreover, a significant number of studies have highlighted the link between mould presence and the prevalence of respiratory diseases. In recent years, the proportion of biobased materials used in construction has been increasing, as seen as an effective lever to reduce the environmental impact of the building sector. Besides, bio-based materials are also hygroscopic materials: when in contact with the wet air of a surrounding environment, their porous structures enable a better capture of water molecules, thus providing a more suitable background for mould growth. Many studies have been conducted to develop reliable models to be able to predict mould appearance, growth, and decay over many building materials and external exposures. Some of them require information about temperature and/or relative humidity, exposure times, material sensitivities, etc. Nevertheless, several studies have highlighted a large disparity between predictions and actual mould growth in experimental settings as well as in occupied buildings. The difficulty of considering the influence of all parameters appears to be the most challenging issue. As many complex phenomena take place simultaneously, a preliminary study has been carried out to evaluate the feasibility to sadopt a reliability approach rather than a deterministic approach. Both epistemic and random uncertainties were identified specifically for the prediction of mould appearance and growth. Several studies published in the literature were selected and analysed, from the agri-food or automotive sectors, as the deployed methodology appeared promising.

Keywords: bio-based materials, mould growth, numerical prediction, reliability approach

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1537 Appraisal of Trace Elements in Scalp Hair of School Children in Kandal Province, Cambodia

Authors: Alireza Yavar, Sukiman Sarmani, Kok Siong Khoo

Abstract:

Trace element analysis of human hair has the potential to disclose retroactive information about an individual’s nutritional status and exposure. The residents of villages in Kandal province of Cambodia, due to dietary habits, lifestyle and ecological conditions, are unprotected from toxic elements particularly arsenic (As). The purpose of this research was to valuation levels of toxic and vital elements in scalp human hair. Scalp hair samples of 12-17 school children from three villages of Anglong Romiot (AR), Svay Romiot (SR) and Kampong Kong (KK) in the Kandal province of Cambodia were evaluated using k0- instrumental neutron activation method (k0-INAA). The samples were irradiated 6 hours in a Malaysian nuclear agency (MNA) research reactor and afterward, an HPGe detector was utilized to obtain gamma peaks of radionuclides in samples. We achieved profiles of 31 elements in human hair in our studied area, namely, As, Au, Br, Ca, Ce, Co, Dy, Eu152m, Hg197, Hg203, Ho, Ir, K, La, Lu, Mn, Na, Pa, Pt195m, Pt197, Sb, Sc46, Sc47, Sm, Sn117m, W181, W187, Yb169, Yb175, Zn and Zn69m. The precision of the method was assessed by evaluating ERM-DB001-human hair as certified reference materials (CRMs), and which experimental result of ERM-DB001 was consistent with certified values. Whereas Arsenic (As) pollution is major contamination in our studied area, correlation between the concentration of As and other elements were determined by Pearson’s correlation test that it may be useful as a database source for toxic and essential elements in the hair of teenage individuals in our studied area

Keywords: scalp human hair, toxic and essential elements, Kandal province of Cambodia, k₀- instrumental neutron activation method

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1536 Effect of Naphtha in Addition to a Cycle Steam Stimulation Process Reducing the Heavy Oil Viscosity Using a Two-Level Factorial Design

Authors: Nora A. Guerrero, Adan Leon, María I. Sandoval, Romel Perez, Samuel Munoz

Abstract:

The addition of solvents in cyclic steam stimulation is a technique that has shown an impact on the improved recovery of heavy oils. In this technique, it is possible to reduce the steam/oil ratio in the last stages of the process, at which time this ratio increases significantly. The mobility of improved crude oil increases due to the structural changes of its components, which at the same time reflected in the decrease in density and viscosity. In the present work, the effect of the variables such as temperature, time, and weight percentage of naphtha was evaluated, using a factorial design of experiments 23. From the results of analysis of variance (ANOVA) and Pareto diagram, it was possible to identify the effect on viscosity reduction. The experimental representation of the crude-vapor-naphtha interaction was carried out in a batch reactor on a Colombian heavy oil of 12.8° API and 3500 cP. The conditions of temperature, reaction time, and percentage of naphtha were 270-300 °C, 48-66 hours, and 3-9% by weight, respectively. The results showed a decrease in density with values in the range of 0.9542 to 0.9414 g/cm³, while the viscosity decrease was in the order of 55 to 70%. On the other hand, simulated distillation results, according to ASTM 7169, revealed significant conversions of the 315°C+ fraction. From the spectroscopic techniques of nuclear magnetic resonance NMR, infrared FTIR and UV-VIS visible ultraviolet, it was determined that the increase in the performance of the light fractions in the improved crude is due to the breakdown of alkyl chains. The methodology for cyclic steam injection with naphtha and laboratory-scale characterization can be considered as a practical tool in improved recovery processes.

Keywords: viscosity reduction, cyclic steam stimulation, factorial design, naphtha

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1535 Design of Hybrid Auxetic Metamaterials for Enhanced Energy Absorption under Compression

Authors: Ercan Karadogan, Fatih Usta

Abstract:

Auxetic materials have a negative Poisson’s ratio (NPR), which is not often found in nature. They are metamaterials that have potential applications in many engineering fields. Mechanical metamaterials are synthetically designed structures with unusual mechanical properties. These mechanical properties are dependent on the properties of the matrix structure. They have the following special characteristics, i.e., improved shear modulus, increased energy absorption, and intensive fracture toughness. Non-auxetic materials compress transversely when they are stretched. The system naturally is inclined to keep its density constant. The transversal compression increases the density to balance the loss in the longitudinal direction. This study proposes to improve the crushing performance of hybrid auxetic materials. The re-entrant honeycomb structure has been combined with a star honeycomb, an S-shaped unit cell, a double arrowhead, and a structurally hexagonal re-entrant honeycomb by 9 X 9 cells, i.e., the number of cells is 9 in the lateral direction and 9 in the vertical direction. The Finite Element (FE) and experimental methods have been used to determine the compression behavior of the developed hybrid auxetic structures. The FE models have been developed by using Abaqus software. The specimens made of polymer plastic materials have been 3D printed and subjected to compression loading. The results are compared in terms of specific energy absorption and strength. This paper describes the quasi-static crushing behavior of two types of hybrid lattice structures (auxetic + auxetic and auxetic + non-auxetic). The results show that the developed hybrid structures can be useful to control collapse mechanisms and present larger energy absorption compared to conventional re-entrant auxetic structures.

Keywords: auxetic materials, compressive behavior, metamaterials, negative Poisson’s ratio

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1534 Optimization of Quercus cerris Bark Liquefaction

Authors: Luísa P. Cruz-Lopes, Hugo Costa e Silva, Idalina Domingos, José Ferreira, Luís Teixeira de Lemos, Bruno Esteves

Abstract:

The liquefaction process of cork based tree barks has led to an increase of interest due to its potential innovation in the lumber and wood industries. In this particular study the bark of Quercus cerris (Turkish oak) is used due to its appreciable amount of cork tissue, although of inferior quality when compared to the cork provided by other Quercus trees. This study aims to optimize alkaline catalysis liquefaction conditions, regarding several parameters. To better comprehend the possible chemical characteristics of the bark of Quercus cerris, a complete chemical analysis was performed. The liquefaction process was performed in a double-jacket reactor heated with oil, using glycerol and a mixture of glycerol/ethylene glycol as solvents, potassium hydroxide as a catalyst, and varying the temperature, liquefaction time and granulometry. Due to low liquefaction efficiency resulting from the first experimental procedures a study was made regarding different washing techniques after the filtration process using methanol and methanol/water. The chemical analysis stated that the bark of Quercus cerris is mostly composed by suberin (ca. 30%) and lignin (ca. 24%) as well as insolvent hemicelluloses in hot water (ca. 23%). On the liquefaction stage, the results that led to higher yields were: using a mixture of methanol/ethylene glycol as reagents and a time and temperature of 120 minutes and 200 ºC, respectively. It is concluded that using a granulometry of <80 mesh leads to better results, even if this parameter barely influences the liquefaction efficiency. Regarding the filtration stage, washing the residue with methanol and then distilled water leads to a considerable increase on final liquefaction percentages, which proves that this procedure is effective at liquefying suberin content and lignocellulose fraction.

Keywords: liquefaction, Quercus cerris, polyalcohol liquefaction, temperature

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1533 Quantifying Wave Attenuation over an Eroding Marsh through Numerical Modeling

Authors: Donald G. Danmeier, Gian Marco Pizzo, Matthew Brennan

Abstract:

Although wetlands have been proposed as a green alternative to manage coastal flood hazards because of their capacity to adapt to sea level rise and provision of multiple ecological and social co-benefits, they are often overlooked due to challenges in quantifying the uncertainty and naturally, variability of these systems. This objective of this study was to quantify wave attenuation provided by a natural marsh surrounding a large oil refinery along the US Gulf Coast that has experienced steady erosion along the shoreward edge. The vegetation module of the SWAN was activated and coupled with a hydrodynamic model (DELFT3D) to capture two-way interactions between the changing water level and wavefield over the course of a storm event. Since the marsh response to relative sea level rise is difficult to predict, a range of future marsh morphologies is explored. Numerical results were examined to determine the amount of wave attenuation as a function of marsh extent and the relative contributions from white-capping, depth-limited wave breaking, bottom friction, and flexing of vegetation. In addition to the coupled DELFT3D-SWAN modeling of a storm event, an uncoupled SWAN-VEG model was applied to a simplified bathymetry to explore a larger experimental design space. The wave modeling revealed that the rate of wave attenuation reduces for higher surge but was still significant over a wide range of water levels and outboard wave heights. The results also provide insights to the minimum marsh extent required to fully realize the potential wave attenuation so the changing coastal hazards can be managed.

Keywords: green infrastructure, wave attenuation, wave modeling, wetland

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1532 Stabilization of Lateritic Soil Sample from Ijoko with Cement Kiln Dust and Lime

Authors: Akinbuluma Ayodeji Theophilus, Adewale Olutaiwo

Abstract:

When building roads and paved surfaces, a strong foundation is always essential. A durable material that can withstand years of traffic while staying trustworthy must be used to build the foundation. A frequent problem in the construction of roads and pavements is the lack of high-quality, long-lasting materials for the pavement structure (base, subbase, and subgrade). Hence, this study examined the stabilization of lateritic soil samples from Ijoko with cement kiln dust and lime. The study adopted the experimental design. Laboratory tests were conducted on classification, swelling potential, compaction, California bearing ratio (CBR), and unconfined compressive tests, among others, were conducted on the laterite sample treated with cement kiln dust (CKD) and lime in incremental order of 2% up to 10% of dry weight soft soil sample. The results of the test showed that the studied soil could be classified as an A-7-6 and CL soil using the American Association of State Highway and transport officials (AASHTO) and the unified soil classification system (USCS), respectively. The plasticity (PI) of the studied soil reduced from 30.5% to 29.9% at the application of CKD. The maximum dry density on the application of CKD reduced from 1.9.7 mg/m3 to 1.86mg/m3, and lime application yielded a reduction from 1.97mg/m3 to 1.88.mg/m3. The swell potential on CKD application was reduced from 0.05 to 0.039%. The study concluded that soil stabilizations are effective and economic way of improving road pavement for engineering benefit. The degree of effectiveness of stabilization in pavement construction was found to depend on the type of soil to be stabilized. The study therefore recommended that stabilized soil mixtures should be used to subbase material for flexible pavement since is a suitable.

Keywords: lateritic soils, sand, cement, stabilization, road pavement

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1531 An In-Depth Experimental Study of Wax Deposition in Pipelines

Authors: Arias M. L., D’Adamo J., Novosad M. N., Raffo P. A., Burbridge H. P., Artana G.

Abstract:

Shale oils are highly paraffinic and, consequently, can create wax deposits that foul pipelines during transportation. Several factors must be considered when designing pipelines or treatment programs that prevents wax deposition: including chemical species in crude oils, flowrates, pipes diameters and temperature. This paper describes the wax deposition study carried out within the framework of Y-TEC's flow assurance projects, as part of the process to achieve a better understanding on wax deposition issues. Laboratory experiments were performed on a medium size, 1 inch diameter, wax deposition loop of 15 mts long equipped with a solid detector system, online microscope to visualize crystals, temperature and pressure sensors along the loop pipe. A baseline test was performed with diesel with no paraffin or additive content. Tests were undertaken with different temperatures of circulating and cooling fluid at different flow conditions. Then, a solution formed with a paraffin added to the diesel was considered. Tests varying flowrate and cooling rate were again run. Viscosity, density, WAT (Wax Appearance Temperature) with DSC (Differential Scanning Calorimetry), pour point and cold finger measurements were carried out to determine physical properties of the working fluids. The results obtained in the loop were analyzed through momentum balance and heat transfer models. To determine possible paraffin deposition scenarios temperature and pressure loop output signals were studied. They were compared with WAT static laboratory methods. Finally, we scrutinized the effect of adding a chemical inhibitor to the working fluid on the dynamics of the process of wax deposition in the loop.

Keywords: paraffin desposition, flow assurance, chemical inhibitors, flow loop

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1530 Low-Cost Image Processing System for Evaluating Pavement Surface Distress

Authors: Keerti Kembhavi, M. R. Archana, V. Anjaneyappa

Abstract:

Most asphalt pavement condition evaluation use rating frameworks in which asphalt pavement distress is estimated by type, extent, and severity. Rating is carried out by the pavement condition rating (PCR), which is tedious and expensive. This paper presents the development of a low-cost technique for image pavement distress analysis that permits the identification of pothole and cracks. The paper explores the application of image processing tools for the detection of potholes and cracks. Longitudinal cracking and pothole are detected using Fuzzy-C- Means (FCM) and proceeded with the Spectral Theory algorithm. The framework comprises three phases, including image acquisition, processing, and extraction of features. A digital camera (Gopro) with the holder is used to capture pavement distress images on a moving vehicle. FCM classifier and Spectral Theory algorithms are used to compute features and classify the longitudinal cracking and pothole. The Matlab2016Ra Image preparing tool kit utilizes performance analysis to identify the viability of pavement distress on selected urban stretches of Bengaluru city, India. The outcomes of image evaluation with the utilization semi-computerized image handling framework represented the features of longitudinal crack and pothole with an accuracy of about 80%. Further, the detected images are validated with the actual dimensions, and it is seen that dimension variability is about 0.46. The linear regression model y=1.171x-0.155 is obtained using the existing and experimental / image processing area. The R2 correlation square obtained from the best fit line is 0.807, which is considered in the linear regression model to be ‘large positive linear association’.

Keywords: crack detection, pothole detection, spectral clustering, fuzzy-c-means

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1529 Composition Dependent Spectroscopic Studies of Sm3+-Doped Alkali Fluoro Tungsten Tellurite Glasses

Authors: K. Swapna, Sk. Mahamuda, Ch, Annapurna, A. Srinivasa Rao, G. Vijaya Prakash

Abstract:

Samarium ions doped Alkali Fluoro Tungsten Tellurite (AFTT) Glasses have been prepared by using the melt quenching technique and characterized through various spectroscopic techniques such as optical absorption, excitation, emission and decay spectral studies. From the measured absorption spectra of Sm3+ ions in AFTT glasses, the optical band gap and Urbach energies have been evaluated. The spectroscopic parameters such as oscillator strengths (f), Judd-Ofelt (J-O) intensity parameters (Ωλ), spontaneous emission probability (AR), branching ratios (βR) and radiative lifetimes (τR) of various excited levels have been determined from the absorption spectrum by using J-O analysis. A strong luminescence in the reddish-orange spectral region has been observed for all the Sm3+ ions doped AFTT glasses. It consisting four emission transitions occurring from the 4G5/2metastable state to the lower lying states 6H5/2, 6H7/2, 6H9/2 and 6H11/2 upon exciting the sample with a 478 nm line of an argon ion laser. The stimulated emission cross-sections (σe) and branching ratios (βmeas) were estimated from the emission spectra for all emission transitions. Correlation of the radiative lifetime with the experimental lifetime measured from the day curves allows us to measure the quantum efficiency of the prepared glasses. In order to know the colour emission of the prepared glasses under near UV excitation, the emission intensities were analyzed using CIE 1931 colour chromaticity diagram. The aforementioned spectral studies carried out on Sm3+ ions doped AFTT glasses allowed us to conclude that, these glasses are best suited for orange-red visible lasers.

Keywords: fluoro tungsten tellurite glasses, judd-ofelt intensity parameters, lifetime, stimulated emission cross-section

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1528 Communication Infrastructure Required for a Driver Behaviour Monitoring System, ‘SiaMOTO’ IT Platform

Authors: Dogaru-Ulieru Valentin, Sălișteanu Ioan Corneliu, Ardeleanu Mihăiță Nicolae, Broscăreanu Ștefan, Sălișteanu Bogdan, Mihai Mihail

Abstract:

The SiaMOTO system is a communications and data processing platform for vehicle traffic. The human factor is the most important factor in the generation of this data, as the driver is the one who dictates the trajectory of the vehicle. Like any trajectory, specific parameters refer to position, speed and acceleration. Constant knowledge of these parameters allows complex analyses. Roadways allow many vehicles to travel through their confined space, and the overlapping trajectories of several vehicles increase the likelihood of collision events, known as road accidents. Any such event has causes that lead to its occurrence, so the conditions for its occurrence are known. The human factor is predominant in deciding the trajectory parameters of the vehicle on the road, so monitoring it by knowing the events reported by the DiaMOTO device over time, will generate a guide to target any potentially high-risk driving behavior and reward those who control the driving phenomenon well. In this paper, we have focused on detailing the communication infrastructure of the DiaMOTO device with the traffic data collection server, the infrastructure through which the database that will be used for complex AI/DLM analysis is built. The central element of this description is the data string in CODEC-8 format sent by the DiaMOTO device to the SiaMOTO collection server database. The data presented are specific to a functional infrastructure implemented in an experimental model stage, by installing on a number of 50 vehicles DiaMOTO unique code devices, integrating ADAS and GPS functions, through which vehicle trajectories can be monitored 24 hours a day.

Keywords: DiaMOTO, Codec-8, ADAS, GPS, driver monitoring

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1527 Comparative Study of Electronic and Optical Properties of Ammonium and Potassium Dinitramide Salts through Ab-Initio Calculations

Authors: J. Prathap Kumar, G. Vaitheeswaran

Abstract:

The present study investigates the role of ammonium and potassium ion in the electronic, bonding and optical properties of dinitramide salts due to their stability and non-toxic nature. A detailed analysis of bonding between NH₄ and K with dinitramide, optical transitions from the valence band to the conduction band, absorption spectra, refractive indices, reflectivity, loss function are reported. These materials are well known as oxidizers in solid rocket propellants. In the present work, we use full potential linear augmented plane wave (FP-LAPW) method which is implemented in the Wien2k package within the framework of density functional theory. The standard DFT functional local density approximation (LDA) and generalized gradient approximation (GGA) always underestimate the band gap by 30-40% due to the lack of derivative discontinuities of the exchange-correlation potential with respect to an occupation number. In order to get reliable results, one must use hybrid functional (HSE-PBE), GW calculations and Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. It is very well known that hybrid functionals GW calculations are very expensive, the later methods are computationally cheap. The new developed TB-mBJ functionals use information kinetic energy density along with the charge density employed in DFT. The TB-mBJ functionals cannot be used for total energy calculations but instead yield very much improved band gap. The obtained electronic band gap at gamma point for both the ammonium dinitramide and potassium dinitramide are found to be 2.78 eV and 3.014 eV with GGA functional, respectively. After the inclusion of TB-mBJ, the band gap improved by 4.162 eV for potassium dinitramide and 4.378 eV for ammonium dinitramide. The nature of the band gap is direct in ADN and indirect in KDN. The optical constants such as dielectric constant, absorption, and refractive indices, birefringence values are presented. Overall as there are no experimental studies we present the improved band gap with TB-mBJ functional following with optical properties.

Keywords: ammonium dinitramide, potassium dinitramide, DFT, propellants

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1526 Research of Actuators of Common Rail Injection Systems with the Use of LabVIEW on a Specially Designed Test Bench

Authors: G. Baranski, A. Majczak, M. Wendeker

Abstract:

Currently, the most commonly used solution to provide fuel to the diesel engines is the Common Rail system. Compared to previous designs, as a due to relatively simple construction and electronic control systems, these systems allow achieving favourable engine operation parameters with particular emphasis on low emission of toxic compounds into the atmosphere. In this system, the amount of injected fuel dose is strictly dependent on the course of parameters of the electrical impulse sent by the power amplifier power supply system injector from the engine controller. The article presents the construction of a laboratory test bench to examine the course of the injection process and the expense in storage injection systems. The test bench enables testing of injection systems with electromagnetically controlled injectors with the use of scientific engineering tools. The developed system is based on LabView software and CompactRIO family controller using FPGA systems and a real time microcontroller. The results of experimental research on electromagnetic injectors of common rail system, controlled by a dedicated National Instruments card, confirm the effectiveness of the presented approach. The results of the research described in the article present the influence of basic parameters of the electric impulse opening the electromagnetic injector on the value of the injected fuel dose. Acknowledgement: This work has been realized in the cooperation with The Construction Office of WSK ‘PZL-KALISZ’ S.A.’ and is part of Grant Agreement No. POIR.01.02.00-00-0002/15 financed by the Polish National Centre for Research and Development.

Keywords: fuel injector, combustion engine, fuel pressure, compression ignition engine, power supply system, controller, LabVIEW

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1525 Value Proposition and Value Creation in Network Environments: An Experimental Study of Academic Productivity via the Application of Bibliometrics

Authors: R. Oleko, A. Saraceni

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The aim of this research is to provide a rigorous evaluation of the existing academic productivity in relation to value proposition and creation in networked environments. Bibliometrics is a vigorous approach used to structure existing literature in an objective and reliable manner. To that aim, a thorough bibliometric analysis was performed in order to assess the large volume of the information encountered in a structured and reliable manner. A clear distinction between networks and service networks was considered indispensable in order to capture the effects of each network’s type properties on value creation processes. Via the use of bibliometric parameters, this review was able to capture the state-of-the-art in both value proposition and value creation consecutively. The results provide a rigorous assessment of the annual scientific production, the most influential journals, and the leading corresponding author countries. By means of citation analysis, the most frequently cited manuscripts and countries for each network type were identified. Moreover, by means of co-citation analysis, existing collaborative patterns were detected through the creation of reference co-citation networks and country collaboration networks. Co-word analysis was also performed in order to provide an overview of the conceptual structure in both networks and service networks. The acquired results provide a rigorous and systematic assessment of the existing scientific output in networked settings. As such, they positively contribute to a better understanding of the distinct impact of service networks on value proposition and value creation when compared to regular networks. The implications derived can serve as a guide for informed decision-making by practitioners during network formation and provide a structured evaluation that can stand as a basis for future research in the field.

Keywords: bibliometrics, co-citation analysis, networks, service networks, value creation, value proposition

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1524 An Experimental Investigation on the Fuel Characteristics of Nano-Aluminium Oxide and Nano-Cobalt Oxide Particles Blended in Diesel Fuel

Authors: S. Singh, P. Patel, D. Kachhadiya, Swapnil Dharaskar

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The research objective is to integrate nanoparticles into fuels- i.e. diesel, biodiesel, biodiesel blended with diesel, plastic derived fuels, etc. to increase the fuel efficiency. The metal oxide nanoparticles will reduce the carbon monoxide emissions by donating oxygen atoms from their lattices to catalyze the combustion reactions and to aid complete combustion; due to this, there will be an increase in the calorific value of the blend (fuel + metal nanoparticles). Aluminium oxide and cobalt oxide nanoparticles have been synthesized by sol-gel method. The characterization was done by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The size of the particles was determined by XRD to be 28.6 nm and 28.06 nm for aluminium oxide and cobalt oxide nanoparticles respectively. Different concentration blends- 50, 100, 150 ppm were prepared by adding the required weight of metal oxides in 1 liter of diesel and sonicating for 30 minutes at 500W. The blend properties- calorific value, viscosity, and flash point were determined by bomb calorimeter, Brookfield viscometer and pensky-martin apparatus. For the aluminum oxide blended diesel, there was a maximum increase of 5.544% in the calorific value, but at the same time, there was an increase in the flash point from 43°C to 58.5°C and an increase in the viscosity from 2.45 cP to 3.25 cP. On the other hand, for the cobalt oxide blended diesel there was a maximum increase of 2.012% in the calorific value while the flash point increased from 43°C to 51.5°C and the viscosity increased from 2.45 cP to 2.94 cP. There was a linear increase in the calorific value, viscosity and flash point when the concentration of the metal oxide nanoparticles in the blend was increased. For the 50 ppm Al₂O₃ and 50 ppm Co₃O₄ blend the increasing the calorific value was 1.228 %, and the viscosity changed from 2.45 cP to 2.64 cP and the flash point increased from 43°C to 50.5°C. Clearly the aluminium oxide nanoparticles increase the calorific value but at the cost of flash point and viscosity, thus it is better to use the 50 ppm aluminium oxide, and 50 ppm cobalt oxide blended diesel.

Keywords: aluminium oxide nanoparticles, cobalt oxide nanoparticles, fuel additives, fuel characteristics

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1523 Machinability Analysis in Drilling Flax Fiber-Reinforced Polylactic Acid Bio-Composite Laminates

Authors: Amirhossein Lotfi, Huaizhong Li, Dzung Viet Dao

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Interest in natural fiber-reinforced composites (NFRC) is progressively growing both in terms of academia research and industrial applications thanks to their abundant advantages such as low cost, biodegradability, eco-friendly nature and relatively good mechanical properties. However, their widespread use is still presumed as challenging because of the specificity of their non-homogeneous structure, limited knowledge on their machinability characteristics and parameter settings, to avoid defects associated with the machining process. The present work is aimed to investigate the effect of the cutting tool geometry and material on the drilling-induced delamination, thrust force and hole quality produced when drilling a fully biodegradable flax/poly (lactic acid) composite laminate. Three drills with different geometries and material were used at different drilling conditions to evaluate the machinability of the fabricated composites. The experimental results indicated that the choice of cutting tool, in terms of material and geometry, has a noticeable influence on the cutting thrust force and subsequently drilling-induced damages. The lower value of thrust force and better hole quality was observed using high-speed steel (HSS) drill, whereas Carbide drill (with point angle of 130o) resulted in the highest value of thrust force. Carbide drill presented higher wear resistance and stability in variation of thrust force with a number of holes drilled, while HSS drill showed the lower value of thrust force during the drilling process. Finally, within the selected cutting range, the delamination damage increased noticeably with feed rate and moderately with spindle speed.

Keywords: natural fiber reinforced composites, delamination, thrust force, machinability

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1522 The Use of Microbiological Methods to Reduce Aflatoxin M1 in Cheese

Authors: Bruna Goncalves, Jennifer Henck, Romulo Uliana, Eliana Kamimura, Carlos Oliveira, Carlos Corassin

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Studies have shown evidence of human exposure to aflatoxin M1 due to the consumption of contaminated milk and dairy products (mainly cheeses). This poses a great risk to public health, since milk and milk products are frequently consumed by a portion of the population considered immunosuppressed, children and the elderly. Knowledge of the negative impacts of aflatoxins on health and economics has led to investigations of strategies to prevent their formation in food, as well as to eliminate, inactivate or reduce the bioavailability of these toxins in contaminated products This study evaluated the effect of microbiological methods using lactic acid bacteria on aflatoxin M1 (AFM1) reduction in Minas Frescal cheese (typical Brazilian product, being among the most consumed cheeses in Brazil) spiked with 1 µg/L AFM1. Inactivated lactic acid bacteria (0,5%, v/v de L. rhamnosus e L. lactis) were added during the cheese production process. Nine cheeses were produced, divided into three treatments: negative controls (without AFM1 or lactic acid bacteria), positive controls (AFM1 only), and lactic acid bacteria + AFM1. Samples of cheese were collected on days 2, 10, 20 and 30 after the date of production and submitted to composition analyses and determination of AFM1 by high-performance liquid chromatography. The reductions of AFM1 in cheese by lactic acid bacteria at the end of the trial indicate a potential application of inactivated lactic acid bacteria in reducing the bioavailability of AFM1 in Minas frescal cheese without physical-chemical and microbiological modifications during the 30-day experimental period. The authors would like to thank São Paulo Research Foundation – FAPESP (grants #2017/20081-6 and #2017/19683-1).

Keywords: aflatoxin, milk, minas frescal cheese, decontamination

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1521 Effect of Diet Inulin Prebiotic on Growth, Reproductive Performance, Carcass Composition and Resistance to Environmental Stresses in Zebra Danio (Danio rerio)

Authors: Ehsan Ahmadifar

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In this research, the effects of different levels (control group (T0), (T1)1, (T2)2 and (T3)3 gr Inulin per Kg diet) of prebiotic Inulin as nutritional supplement on Danio rerio were investigated for 4 month. Since the beginning of feeding larvae until adult (average weight: 67.1 g, length: 4.5 cm) were fed with experimental diets. The survival rate of fish had no significant effect on rate survival (P > 0.05). The highest food conversion ratio (FCR) was in control group and the lowest was observed in T3. Treatment of T3 significantly caused the best feed conversion ratio in Zebra fish (P < 0.05). By increasing the inulin diet during the experiment, specific growth rate increased. The highest and the lowest body weight gain and condition factor were observed in T3 and control, respectively (P < 0.05). Adding 3 gr inulin in Zebra fish diet can improve the performance of the growth indices and final biomass, also this prebiotic can be considered as a suitable supplement for Cyprinidae diet. In the first sampling stage for feeding fish, fat and muscle protein was significantly higher than the second sampling stage (P < 0.05). Given that the second stage fish were full sexual maturity, the amount of fat in muscle decreased (P < 0.05). Moisture and ash levels were significantly (P < 0.05) higher in the second stage sampling than the first stage. Overall, different stage of living affected on muscle chemical composition muscle. Reproductive performance in treatment T2 and T3 were significantly higher than other treatments (P < 0.05). According to the results, the prebiotic inulin does not have a significant impact on the sex ratio in zebrafish (P > 0.05). Based on histology of the gonads, the use of dietary inulin accelerates the process of gonad development in zebrafish.

Keywords: inulin, zebrafish, reproduction, histology

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1520 Nimbus Radiance Gate Project: Media Architecture in Sacred Space

Authors: Jorge Duarte de Sá

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The project presented in this investigation is part of the multidisciplinary field of Architecture and explores an experience in media architecture, integrated in Arts, Science and Technology. The objective of this work is to create a visual experience comprehending Architecture, Media and Art. It is intended to specifically explore the sacred spaces that are losing social, cultural or religious dynamics and insert new Media technologies to create a new generate momentum, testing tools, techniques and methods of implementation. Given an architectural project methodology, it seems essential that 'the location' should be the starting point for the development of this technological apparatus: the church of Santa Clara in Santarém, Portugal emerged as an experimental space for apparatus, presenting itself as both temple and museum. We also aim to address the concept of rehabilitation through media technologies, directed at interventions that may have an impact on energizing spaces. The idea is emphasized on the rehabilitation of spaces that, one way or another, may gain new dynamics after a media intervention. Thus, we intend to affect the play with a sensitive and spiritual character which endemically, sacred spaces have, by exploring a sensitive aspect of the subject and drawing up new ideas for meditation and spiritual reflection. The work is designed primarily as a visual experience that encompasses the space, the object and the subject. It is a media project supported by a dual structure with two transparent screens operating in a holographic screen which will be projecting two images that complement the translucent overlay film, thus making the merger of two projections. The digitally created content reacts to the presence of observers through infrared cameras, placed strategically. The object revives the memory of the altarpiece as an architectural surface, promoting the expansion of messages through the media technologies.

Keywords: architecture, media, sacred, technology

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1519 A Comprehensive Study and Evaluation on Image Fashion Features Extraction

Authors: Yuanchao Sang, Zhihao Gong, Longsheng Chen, Long Chen

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Clothing fashion represents a human’s aesthetic appreciation towards everyday outfits and appetite for fashion, and it reflects the development of status in society, humanity, and economics. However, modelling fashion by machine is extremely challenging because fashion is too abstract to be efficiently described by machines. Even human beings can hardly reach a consensus about fashion. In this paper, we are dedicated to answering a fundamental fashion-related problem: what image feature best describes clothing fashion? To address this issue, we have designed and evaluated various image features, ranging from traditional low-level hand-crafted features to mid-level style awareness features to various current popular deep neural network-based features, which have shown state-of-the-art performance in various vision tasks. In summary, we tested the following 9 feature representations: color, texture, shape, style, convolutional neural networks (CNNs), CNNs with distance metric learning (CNNs&DML), AutoEncoder, CNNs with multiple layer combination (CNNs&MLC) and CNNs with dynamic feature clustering (CNNs&DFC). Finally, we validated the performance of these features on two publicly available datasets. Quantitative and qualitative experimental results on both intra-domain and inter-domain fashion clothing image retrieval showed that deep learning based feature representations far outweigh traditional hand-crafted feature representation. Additionally, among all deep learning based methods, CNNs with explicit feature clustering performs best, which shows feature clustering is essential for discriminative fashion feature representation.

Keywords: convolutional neural network, feature representation, image processing, machine modelling

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1518 Mental Imagery as an Auxiliary Tool to the Performance of Elite Competitive Swimmers of the University of the East Manila

Authors: Hillary Jo Muyalde

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Introduction: Elite athletes train regularly to enhance their physical endurance, but sometimes, training sessions are not enough. When competition comes, these athletes struggle to find focus. Mental imagery is a psychological technique that helps condition the mind to focus and eventually help improve performance. This study aims to help elite competitive swimmers of the University of the East improve their performance with Mental Imagery as an auxiliary tool. Methodology: The study design used was quasi-experimental with a purposive sampling technique and a within-subject design. It was conducted with a total of 41 participants. The participants were given a Sport Imagery Ability Questionnaire (SIAQ) to measure imagery ability and the Mental Imagery Program. The study utilized a Paired T-test for data analysis where the participants underwent six weeks of no mental imagery training and were compared to six weeks with the Mental Imagery Program (MIP). The researcher recorded the personal best time of participants in their respective specialty stroke. Results: The results of the study showed a t-value of 17.804 for Butterfly stroke events, 9.922 for Backstroke events, 7.787 for Breaststroke events, and 17.440 in Freestyle. This indicated that MIP had a positive effect on participants’ performance. The SIAQ result also showed a big difference where -10.443 for Butterfly events, -5.363 for Backstroke, -7.244 for Breaststroke events, and -10.727 for Freestyle events, which meant the participants were able to image better than before MIP. Conclusion: In conclusion, the findings of this study showed that there is indeed an improvement in the performance of the participants after the application of the Mental Imagery Program. It is recommended from this study that the participants continue to use mental imagery as an auxiliary tool to their training regimen for continuous positive results.

Keywords: mental Imagery, personal best time, SIAQ, specialty stroke

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1517 Agronomic Evaluation of Flax Cultivars (Linum Usitatissimum L.) in Response to Irrigation Intervals

Authors: Emad Rashwan, M. Mousa, Ayman EL Sabagh, Celaleddin Barutcular

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Flax is a potential winter crop for Egypt that can be grown for both seed and fiber. The study was conducted during two successive winter seasons of 2013/2014, and 2014/2015 in the experimental farm of El-Gemmeiza Agricultural Research Station, Agriculture research Centre, Egypt. The objective of this work was to evaluate the effect of irrigation intervals (25, 35 and 45) on the seed yield and quality of flax cultivars (Sakha1, Giza9 and Giza10). Obtained results indicate that highly significant for all studied traits among irrigation intervals except oil percentage that was not significant in both seasons. Irrigated flax plants every 35 days gave the maximum values for all characters. In contrast, irrigation every 45 days gave the minimum values for all studied characters under this study. In respect to cultivars, significant differences in most yield and quality characters were found. Furthermore, the performance of Sakha1 cultivar was superior in total plant height, main stem diameter, seed index, seed, oil, biological and straw yield /ha as well as fiber length and fiber fineness. Meanwhile, Giza9 and Giza10 cultivars were surpassed in fiber yield/hand fiber percentage, respectively. The interactions between irrigation intervals and flax cultivars were highly significant for total plant height, main stem diameter, seed, oil, biological and straw yields /ha. Based on the results, all flax cultivars recorded the maximum values for major traits were measured under irrigation of flax plants every 35 days.

Keywords: flax, fiber, irrigation intervals, oil, seed yield

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1516 Towards Designing of a Potential New HIV-1 Protease Inhibitor Using Quantitative Structure-Activity Relationship Study in Combination with Molecular Docking and Molecular Dynamics Simulations

Authors: Mouna Baassi, Mohamed Moussaoui, Hatim Soufi, Sanchaita RajkhowaI, Ashwani Sharma, Subrata Sinha, Said Belaaouad

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Human Immunodeficiency Virus type 1 protease (HIV-1 PR) is one of the most challenging targets of antiretroviral therapy used in the treatment of AIDS-infected people. The performance of protease inhibitors (PIs) is limited by the development of protease mutations that can promote resistance to the treatment. The current study was carried out using statistics and bioinformatics tools. A series of thirty-three compounds with known enzymatic inhibitory activities against HIV-1 protease was used in this paper to build a mathematical model relating the structure to the biological activity. These compounds were designed by software; their descriptors were computed using various tools, such as Gaussian, Chem3D, ChemSketch and MarvinSketch. Computational methods generated the best model based on its statistical parameters. The model’s applicability domain (AD) was elaborated. Furthermore, one compound has been proposed as efficient against HIV-1 protease with comparable biological activity to the existing ones; this drug candidate was evaluated using ADMET properties and Lipinski’s rule. Molecular Docking performed on Wild Type and Mutant Type HIV-1 proteases allowed the investigation of the interaction types displayed between the proteases and the ligands, Darunavir (DRV) and the new drug (ND). Molecular dynamics simulation was also used in order to investigate the complexes’ stability, allowing a comparative study of the performance of both ligands (DRV & ND). Our study suggested that the new molecule showed comparable results to that of Darunavir and may be used for further experimental studies. Our study may also be used as a pipeline to search and design new potential inhibitors of HIV-1 proteases.

Keywords: QSAR, ADMET properties, molecular docking, molecular dynamics simulation.

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