Search results for: slip length
759 Comparative Analysis of Data Gathering Protocols with Multiple Mobile Elements for Wireless Sensor Network
Authors: Bhat Geetalaxmi Jairam, D. V. Ashoka
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Wireless Sensor Networks are used in many applications to collect sensed data from different sources. Sensed data has to be delivered through sensors wireless interface using multi-hop communication towards the sink. The data collection in wireless sensor networks consumes energy. Energy consumption is the major constraints in WSN .Reducing the energy consumption while increasing the amount of generated data is a great challenge. In this paper, we have implemented two data gathering protocols with multiple mobile sinks/elements to collect data from sensor nodes. First, is Energy-Efficient Data Gathering with Tour Length-Constrained Mobile Elements in Wireless Sensor Networks (EEDG), in which mobile sinks uses vehicle routing protocol to collect data. Second is An Intelligent Agent-based Routing Structure for Mobile Sinks in WSNs (IAR), in which mobile sinks uses prim’s algorithm to collect data. Authors have implemented concepts which are common to both protocols like deployment of mobile sinks, generating visiting schedule, collecting data from the cluster member. Authors have compared the performance of both protocols by taking statistics based on performance parameters like Delay, Packet Drop, Packet Delivery Ratio, Energy Available, Control Overhead. Authors have concluded this paper by proving EEDG is more efficient than IAR protocol but with few limitations which include unaddressed issues likes Redundancy removal, Idle listening, Mobile Sink’s pause/wait state at the node. In future work, we plan to concentrate more on these limitations to avail a new energy efficient protocol which will help in improving the life time of the WSN.Keywords: aggregation, consumption, data gathering, efficiency
Procedia PDF Downloads 484758 Innovation of a New Plant Tissue Culture Medium for Large Scale Plantlet Production in Potato (Solanum tuberosum L.)
Authors: Ekramul Hoque, Zinat Ara Eakut Zarin, Ershad Ali
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The growth and development of explants is governed by the effect of nutrient medium. Ammonium nitrate (NH4NO3) as a major salt of stock solution-1 for the preparation of tissue culture medium. But, it has several demerits on human civilization. It is use for the preparation of bomb and other destructive activities. Hence, it is totally ban in our country. A new chemical was identified as a substitute of ammonium nitrate. The concentrations of the other ingredients of major and minor salt were modified from the MS medium. The formulation of new medium is totally different from the MS nutrient composition. The most widely use MS medium composition was used as first check treatment and MS powder (Duchefa Biocheme, The Netherland) was used as second check treatment. The experiments were carried out at the Department of Biotechnology, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh. Two potato varieties viz. Diamant and Asterix were used as experimental materials. The regeneration potentiality of potato onto new medium was best as compare with the two check treatments. The traits -node number, leaf number, shoot length, root lengths were highest in new medium. The plantlets were healthy, robust and strong as compare to plantlets regenerated from check treatments. Three subsequent sub-cultures were made in the new medium to observe the growth pattern of plantlet. It was also showed the best performance in all the parameter under studied. The regenerated plantlet produced good quality minituber under field condition. Hence, it is concluded that, a new plant tissue culture medium as discovered from the Department of Biotechnology, Sher-e-Bangla Agricultural University, Dhaka, Bangladesh under the leadership of Professor Dr. Md. Ekramul Hoque.Keywords: new medium, potato, regeneration, ammonium nitrate
Procedia PDF Downloads 82757 Shape Management Method for Safety Evaluation of Bridge Based on Terrestrial Laser Scanning Using Least Squares
Authors: Gichun Cha, Dongwan Lee, Junkyeong Kim, Aoqi Zhang, Seunghee Park
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All the world are studying the construction technology of double deck tunnel in order to respond to the increasing urban traffic demands and environmental changes. Advanced countries have the construction technology of the double deck tunnel structure. but the domestic country began research on it. Construction technologies are important. But Safety evaluation of structure is necessary to prevent possible accidents during construction. Thus, the double deck tunnel was required the shape management of middle slabs. The domestic country is preparing the construction of double deck tunnel for an alternate route and a pleasant urban environment. Shape management of double deck tunnel has been no research because it is a new attempted technology. The present, a similar study is bridge structure for the shape management. Bridge is implemented shape model using terrestrial laser scanning(TLS). Therefore, we proceed research on the bridge slabs because there is a similar structure of double deck tunnel. In the study, we develop shape management method of bridge slabs using TLS. We select the Test-bed for measurement site. This site is bridge located on Sungkyunkwan University Natural Sciences Campus. This bridge has a total length of 34m, the vertical height of 8.7m from the ground. It connects Engineering Building #1 and Engineering Building #2. Point cloud data for shape management is acquired the TLS and We utilized the Leica ScanStation C10/C5 model. We will confirm the Maximum displacement area of middle slabs using Least-Squares Fitting. We expect to raise stability for double deck tunnel through shape management for middle slabs.Keywords: bridge slabs, least squares, safety evaluation, shape management method, terrestrial laser scanning
Procedia PDF Downloads 233756 Numerical Study of Fluid Flow and Heat Transfer in Microchannel with Thin Obstacles
Authors: Malorzata Kmiotek, Anna Kucaba-Pietal, Robert Smusz
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Due to the miniaturisation process, in many technical devices, microchannels are used in cooling systems. Because of the small size of microchannels, the flow inside is laminar, which caused a slow heat exchange. In order to intensify the heat exchange, the flow must be disturbed, for example, by introducing obstacles. We present results on the influence of a thin obstacle, placed on microchannel wall, on the fluid and heat flow in the aspect of their use by constructors of heat exchangers. The obstacle is called 'thin' when its geometrical parameter (o=w/h, w- width, h - height of the obstacle) satisfies inequality: o < 0.5. In this work, we report numerical results on heat and mass transfer in the microchannels of 400 micrometer height (H - height of the microchannel), where thin obstacles are immersed on the walls, to disturb the flow. The Reynolds number of the flow in microchannel varies between 20 and 200 and is typical for the flow in micro heat exchangers. The equations describing the fluid and heat flows in microchannels were solved numerically by using the finite element method with an application of CFD&FSI package of ADINA R&D, Inc. 9.4 solver. In the case of flows in the microchannels with sequences of thin rectangular obstacles placed on the bottom and the top wall of a microchannel, the influence of distances s (s is the distance between two thin obstacles) and heights of obstacles on the fluid and heat transfer was investigated. Thermal and flow conditions of the application area of microchannels in electronic cooling systems, i.e., wall temperature of 60 °C, the fluid temperature of 20°C were used to solve equations. Additionally, the distance s between the thin obstacles in microchannels as a multiple of the amount of the channel height was determined. Results show that placing thin obstacles on microchannel walls increase the length of recirculation zones of the flow and improves the heat transfer.Keywords: Finite Element Method, heat transfer, mechanical engineering, microchannel
Procedia PDF Downloads 126755 Electrochemical Growth and Properties of Cu2O Nanostructures
Authors: A. Azizi, S. Laidoudi, G. Schmerber, A. Dinia
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Cuprous oxide (Cu2O) is a well-known oxide semiconductor with a band gap of 2.1 eV and a natural p-type conductivity, which is an attractive material for device applications because of its abundant availability, non toxicity, and low production cost. It has a higher absorption coefficient in the visible region and the minority carrier diffusion length is also suitable for use as a solar cell absorber layer and it has been explored in junction with n type ZnO for photovoltaic applications. Cu2O nanostructures have been made by a variety of techniques; the electrodeposition method has emerged as one of the most promising processing routes as it is particularly provides advantages such as a low-cost, low temperature and a high level of purity in the products. In this work, Cu2O nanostructures prepared by electrodeposition from aqueous cupric sulfate solution with citric acid at 65°C onto a fluorine doped tin oxide (FTO) coated glass substrates were investigated. The effects of deposition potential on the electrochemical, surface morphology, structural and optical properties of Cu2O thin films were investigated. During cyclic voltammetry experiences, the potential interval where the electrodeposition of Cu2O is carried out was established. The Mott–Schottky (M-S) plot demonstrates that all the films are p-type semiconductors, the flat-band potential and the acceptor density for the Cu2O thin films are determined. AFM images reveal that the applied potential has a very significant influence on the surface morphology and size of the crystallites of thin Cu2O. The XRD measurements indicated that all the obtained films display a Cu2O cubic structure with a strong preferential orientation of the (111) direction. The optical transmission spectra in the UV-Visible domains revealed the highest transmission (75 %), and their calculated gap values increased from 1.93 to 2.24 eV, with increasing potentials.Keywords: Cu2O, electrodeposition, Mott–Schottky plot, nanostructure, optical properties, XRD
Procedia PDF Downloads 350754 Geometrical Analysis of an Atheroma Plaque in Left Anterior Descending Coronary Artery
Authors: Sohrab Jafarpour, Hamed Farokhi, Mohammad Rahmati, Alireza Gholipour
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In the current study, a nonlinear fluid-structure interaction (FSI) biomechanical model of atherosclerosis in the left anterior descending (LAD) coronary artery is developed to perform a detailed sensitivity analysis of the geometrical features of an atheroma plaque. In the development of the numerical model, first, a 3D geometry of the diseased artery is developed based on patient-specific dimensions obtained from the experimental studies. The geometry includes four influential geometric characteristics: stenosis ratio, plaque shoulder-length, fibrous cap thickness, and eccentricity intensity. Then, a suitable strain energy density function (SEDF) is proposed based on the detailed material stability analysis to accurately model the hyperelasticity of the arterial walls. The time-varying inlet velocity and outlet pressure profiles are adopted from experimental measurements to incorporate the pulsatile nature of the blood flow. In addition, a computationally efficient type of structural boundary condition is imposed on the arterial walls. Finally, a non-Newtonian viscosity model is implemented to model the shear-thinning behaviour of the blood flow. According to the results, the structural responses in terms of the maximum principal stress (MPS) are affected more compared to the fluid responses in terms of wall shear stress (WSS) as the geometrical characteristics are varying. The extent of these changes is critical in the vulnerability assessment of an atheroma plaque.Keywords: atherosclerosis, fluid-Structure interaction modeling, material stability analysis, and nonlinear biomechanics
Procedia PDF Downloads 82753 Microstructure Analysis of TI-6AL-4V Friction Stir Welded Joints
Authors: P. Leo, E. Cerri, L. Fratini, G. Buffa
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The Friction Stir Welding process uses an inert rotating mandrel and a force on the mandrel normal to the plane of the sheets to generate the frictional heat. The heat and the stirring action of the mandrel create a bond between the two sheets without melting the base metal. As matter of fact, the use of a solid state welding process limits the insurgence of defects, due to the presence of gas in melting bath, and avoids the negative effects of materials metallurgical transformation strictly connected with the change of phase. The industrial importance of Ti-6Al-4V alloy is well known. It provides an exceptional good balance of strength, ductility, fatigue and fracture properties together with good corrosion resistance and good metallurgical stability. In this paper, the authors analyze the microstructure of friction stir welded joints of Ti-6Al-4V processed at the same travel speed (35 mm/min) but at different rotation speeds (300-500 rpm). The microstructure of base material (BM), as result from both optical microscope and scanning electron microscope analysis is not homogenous. It is characterized by distorted α/β lamellar microstructure together with smashed zone of fragmented β layer and β retained grain boundary phase. The BM has been welded in the-as received state, without any previous heat treatment. Even the microstructure of the transverse and longitudinal sections of joints is not homogeneous. Close to the top of weld cross sections a much finer microstructure than the initial condition has been observed, while in the center of the joints the microstructure is less refined. Along longitudinal sections, the microstructure is characterized by equiaxed grains and lamellae. Both the length and area fraction of lamellas increases with distance from longitudinal axis. The hardness of joints is higher than that of BM. As the process temperature increases the average microhardness slightly decreases.Keywords: friction stir welding, microhardness, microstructure, Ti-6Al-4V
Procedia PDF Downloads 374752 Ferromagnetic Potts Models with Multi Site Interaction
Authors: Nir Schreiber, Reuven Cohen, Simi Haber
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The Potts model has been widely explored in the literature for the last few decades. While many analytical and numerical results concern with the traditional two site interaction model in various geometries and dimensions, little is yet known about models where more than two spins simultaneously interact. We consider a ferromagnetic four site interaction Potts model on the square lattice (FFPS), where the four spins reside in the corners of an elementary square. Each spin can take an integer value 1,2,...,q. We write the partition function as a sum over clusters consisting of monochromatic faces. When the number of faces becomes large, tracing out spin configurations is equivalent to enumerating large lattice animals. It is known that the asymptotic number of animals with k faces is governed by λᵏ, with λ ≈ 4.0626. Based on this observation, systems with q < 4 and q > 4 exhibit a second and first order phase transitions, respectively. The transition nature of the q = 4 case is borderline. For any q, a critical giant component (GC) is formed. In the finite order case, GC is simple, while it is fractal when the transition is continuous. Using simple equilibrium arguments, we obtain a (zero order) bound on the transition point. It is claimed that this bound should apply for other lattices as well. Next, taking into account higher order sites contributions, the critical bound becomes tighter. Moreover, for q > 4, if corrections due to contributions from small clusters are negligible in the thermodynamic limit, the improved bound should be exact. The improved bound is used to relate the critical point to the finite correlation length. Our analytical predictions are confirmed by an extensive numerical study of FFPS, using the Wang-Landau method. In particular, the q=4 marginal case is supported by a very ambiguous pseudo-critical finite size behavior.Keywords: entropic sampling, lattice animals, phase transitions, Potts model
Procedia PDF Downloads 152751 Application of the Best Technique for Estimating the Rest-Activity Rhythm Period in Shift Workers
Authors: Rakesh Kumar Soni
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Under free living conditions, human biological clocks show a periodicity of 24 hour for numerous physiological, behavioral and biochemical variables. However, this period is not the original period; rather it merely exhibits synchronization with the solar clock. It is, therefore, most important to investigate characteristics of human circadian clock, essentially in shift workers, who normally confront with contrasting social clocks. Aim of the present study was to investigate rest-activity rhythm and to vouch for the best technique for the computation of periods in this rhythm in subjects randomly selected from different groups of shift workers. The rest-activity rhythm was studied in forty-eight shift workers from three different organizations, namely Newspaper Printing Press (NPP), Chhattisgarh State Electricity Board (CSEB) and Raipur Alloys (RA). Shift workers of NPP (N = 20) were working on a permanent night shift schedule (NS; 20:00-04:00). However, in CSEB (N = 14) and RA (N = 14), shift workers were working in a 3-shift system comprising of rotations from night (NS; 22:00-06:00) to afternoon (AS; 14:00-22:00) and to morning shift (MS; 06:00-14:00). Each subject wore an Actiwatch (AW64, Mini Mitter Co. Inc., USA) for 7 and/or 21 consecutive days, only after furnishing a certificate of consent. One-minute epoch length was chosen for the collection of wrist activity data. Period was determined by using Actiware sleep software (Periodogram), Lomb-Scargle Periodogram (LSP) and Spectral analysis software (Spectre). Other statistical techniques, such as ANOVA and Duncan’s multiple-range test were also used whenever required. A statistically significant circadian rhythm in rest-activity, gauged by cosinor, was documented in all shift workers, irrespective of shift work. Results indicate that the efficiency of the technique to determine the period (τ) depended upon the clipping limits of the τs. It appears that the technique of spectre is more reliable.Keywords: biological clock, rest activity rhythm, spectre, periodogram
Procedia PDF Downloads 154750 Experimental Investigations on the Mechanical properties of Spiny (Kawayan Tinik) Bamboo Layers
Authors: Ma. Doreen E. Candelaria, Ma. Louise Margaret A. Ramos, Dr. Jaime Y. Hernandez, Jr
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Bamboo has been introduced as a possible alternative to some construction materials nowadays. Its potential use in the field of engineering, however, is still not widely practiced due to insufficient engineering knowledge on the material’s properties and characteristics. Although there are researches and studies proving its advantages, it is still not enough to say that bamboo can sustain and provide the strength and capacity required of common structures. In line with this, a more detailed analysis was made to observe the layered structure of the bamboo, particularly the species of Kawayan Tinik. It is the main intent of this research to provide the necessary experiments to determine the tensile strength of dried bamboo samples. The test includes tensile strength parallel to fibers with samples taken at internodes only. Throughout the experiment, methods suggested by the International Organization for Standardization (ISO) were followed. The specimens were tested using 3366 INSTRON Universal Testing Machine, with a rate of loading set to 0.6 mm/min. It was then observed from the results of these experiments that dried bamboo samples recorded high layered tensile strengths, as high as 600 MPa. Likewise, along the culm’s length and across its cross section, higher tensile strength were observed at the top part and at its outer layers. Overall, the top part recorded the highest tensile strength per layer, with its outer layers having tensile strength as high as 600 MPa. The recorded tensile strength of its middle and inner layers, on the other hand, were approximately 450 MPa and 180 MPa, respectively. From this variation in tensile strength across the cross section, it may be concluded that an increase in tensile strength may be observed towards the outer periphery of the bamboo. With these preliminary investigations on the layered tensile strength of bamboo, it is highly recommended to conduct experimental investigations on the layered compressive strength properties as well. It is also suggested to conduct investigations evaluating perpendicular layered tensile strength of the material.Keywords: bamboo strength, layered strength tests, strength test, tensile test
Procedia PDF Downloads 397749 Factors Associated with Stunting at Birth and at 6 Weeks in the Northern Cape Province, South Africa
Authors: Maretha Le Roux, Corinna Walsh, Mariette M. Nel
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Introduction: The first 1000 days from conception to 24 months, is a critical period for healthy growth and development. In South Africa, stunting is a major public health issue with significant health consequences. We determined associations between demographic, health and anthropometric indicators of mothers and their infants. Methods: A cross-sectional study was conducted in all districts in the Northern Cape. All mothers with 5-7 week old babies visiting PHC facilities could participate. A questionnaire was completed in a structured interview with each mother. Weight and length of the baby at birth and at 6 weeks were used to determine stunting, while weight and height of the mother were measured for body mass index (BMI). Results: Eight hundred questionnaires were completed in 92 facilities. The median age of mothers was 26 years (range 10-46 years), and 44,9% were married. Almost 40% relied on a government grant as main source of income. Two-thirds (64,9%) had not planned the pregnancy, and 19.4% had a Caesarian section. Although 79% breastfed exclusively, more than a quarter (26,1%) smoked cigarettes or used snuff during pregnancy, while 9,4% drank alcohol. At birth, 17.7% of boys and 13.0% of girls were stunted (height-for-age below -2SD from the WHO reference values), while at 6 weeks this had increased to 30.8% of boys and 14.1% of girls. In terms of mothers, 25,4% were classified as obese and 24,6% as overweight at 6 weeks. Compared to babies that were not stunted, significantly more babies of mothers that were older, overweight, used ART, relied on a grant and smoked/snuffed during pregnancy were stunted. Conclusion: To address stunting, interventions aimed at encouraging healthy lifestyles with the emphasis on maintaining a healthy weight, healthy eating and smoking cessation before pregnancy are urgently required.Keywords: growth, health, South Africa, stunting
Procedia PDF Downloads 119748 Morphometric Parameters and Evaluation of Persian Fallow Deer Semen in Dashenaz Refuge in Iran
Authors: Behrang Ekrami, Amin Tamadon
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Persian fallow deer (Dama dama mesopotamica) is belonging to the family Cervidae and is only found in a few protected areas in the northwest, north, and southwest of Iran. The aims of this study were analysis of inbreeding and morphometric parameters of semen in male Persian fallow deer to investigate the cause of reduced fertility of this endangered species in Dasht-e-Naz National Refuge, Sari, Iran. The Persian fallow deer semen was collected from four adult bucks randomly during the breeding and non-breeding season from five dehorned and horned deer's BY an artificial vagina. Twelve blood samples was taken from Persian fallow deer and mitochondrial DNA was extracted, amplified, extracted, sequenced, and then were considered for genetic analysis. The Persian fallow deer semen, both with normal and abnormal spermatozoa, is similar to that of domestic ruminants but very smaller and difficult to observe at the primary observation. The post-mating season collected ejaculates contained abnormal spermatozoa, debris and secretion of accessory glands in horned bucks and accessory glands secretion free of any spermatozoa in dehorned or early velvet budding bucks. Microscopic evaluation in all four bucks during the mating season showed the mean concentration of 9×106 spermatozoa/ml. The mean ±SD of age, testes length and testes width was 4.60±1.52 years, 3.58±0.32 and 1.86±0.09 cm, respectively. The results identified 1120 loci (assuming each nucleotide as locus) in which 377 were polymorphic. In conclusion, reduced fertility of male Persian fallow deer may be caused by inbreeding of the protected herd in a limited area of Dasht-e-Naz National Refuge.Keywords: Persian fallow deer, spermatozoa, reproductive characteristics, morphometric parameters
Procedia PDF Downloads 566747 Quality of Ram Semen in Relation to Scrotal Biometry
Authors: M. M. Islam, S. Sharmin, M. Shah Newaz, N. S. Juyena, M. M. Rahman, P. K. Jha, F. Y. Bari
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The aim of the present study was to select the high quality ram by measuring the scrotal biometry which has an effect on semen parameters. Ten rams were selected in the present study. Eight ejaculates were collected from each ram using artificial vagina method. Scrotal circumference was measured before and after semen collection on weekly basis using the Scrotal tape. Bio-metries of scrotum (scrotal length and scrotal volume) were calculated. Semen was evaluated for macroscopic and microscopic characteristics. The average estimated scrotal circumference (cm) and scrotal volume (cm3) in 8 different age groups were 17.16±0.05 cm and 61.30±0.70 cm3, 17.17±0.62 cm and 63.67±4.49 cm3, 17.22±0.52 cm and 64.90±4.21 cm3, 17.72±0.37 cm and 67.10±4.20 cm3, 18.41±0.35cm and 69.52±4.12cm3, 18.45±0.36cm and 77.17±3.81 cm3, 18.55±0.41 cm and 78.72±4.90 cm3, 19.10±0.30 cm and 87.35±5.45 cm3 respectively. The body weight, scrotal circumference and scrotal volume increased with the progress of age (P < 0.05). Body weight of age group 381-410 days (13.62+1.48 kg) was significantly higher than group 169-200 days (10.17±0.05 kg) and 201-230 days (10.42±1.18 kg) (p < 0.05). Scrotal circumference (SC) of age group 381-410 days (19.10±0.30 cm) was significantly higher (p < 0.05) than other groups. In age group 381-410 days, scrotal volume (SCV) (87.35±5.45 cm3) was significantly higher than other first five groups (p < 0.05). Both scrotal circumference and scrotal volume development was positively correlated with the increasing of body weight (R2= 0.51). Semen volume increased accordingly with the increasing of ages, varied from 0.35±0.00 ml to 1.15+0.26 ml. Semen volume of age group 381-410 days (1.15±0.26 ml) was significantly higher than other age groups (p < 0.05) except age group 351-380 days (p > 0.05). Mass activity of different age groups varied from 2.75 (±0.35) to 4.25 (±0.29) ml in the scale of 1-5. Sperm concentration, progressive motility (%),progressively improved according to the increasing of ages, but significant changes in these parameters were seen when the animals reaches the age 291 days or more (p < 0.05). However, normal spermatozoa (%) improved significantly from the age of 261 days or more. Mass activity (mass) was positively correlated with sperm concentration (R2=0.568) and progressive motility (%) (R2=0.616). The relationships of semen volume with body weight and scrotal measurements and sperm concentration indicate that they are useful in evaluating rams for breeding soundness and genetic improvement for fertility in indigenous ram.Keywords: breeding soundness, ram, semen quality, scrotal biometry
Procedia PDF Downloads 356746 Estimation of Soil Erosion Potential in Herat Province, Afghanistan
Authors: M. E. Razipoor, T. Masunaga, K. Sato, M. S. Saboory
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Estimation of soil erosion is economically and environmentally important in Herat, Afghanistan. Degradation of soil has negative impact (decreased soil fertility, destroyed soil structure, and consequently soil sealing and crusting) on life of Herat residents. Water and wind are the main erosive factors causing soil erosion in Herat. Furthermore, scarce vegetation cover, exacerbated by socioeconomic constraint, and steep slopes accelerate soil erosion. To sustain soil productivity and reduce soil erosion impact on human life, due to sustaining agricultural production and auditing the environment, it is needed to quantify the magnitude and extent of soil erosion in a spatial domain. Thus, this study aims to estimate soil loss potential and its spatial distribution in Herat, Afghanistan by applying RUSLE in GIS environment. The rainfall erosivity factor ranged between values of 125 and 612 (MJ mm ha-1 h-1 year-1). Soil erodibility factor varied from 0.036 to 0.073 (Mg h MJ-1 mm-1). Slope length and steepness factor (LS) values were between 0.03 and 31.4. The vegetation cover factor (C), derived from NDVI analysis of Landsat-8 OLI scenes, resulting in range of 0.03 to 1. Support practice factor (P) were assigned to a value of 1, since there is not significant mitigation practices in the study area. Soil erosion potential map was the product of these factors. Mean soil erosion rate of Herat Province was 29 Mg ha-1 year-1 that ranged from 0.024 Mg ha-1 year-1 in flat areas with dense vegetation cover to 778 Mg ha-1 year-1 in sharp slopes with high rainfall but least vegetation cover. Based on land cover map of Afghanistan, areas with soil loss rate higher than soil loss tolerance (8 Mg ha-1 year-1) occupies 98% of Forests, 81% rangelands, 64% barren lands, 60% rainfed lands, 28% urban area and 18% irrigated Lands.Keywords: Afghanistan, erosion, GIS, Herat, RUSLE
Procedia PDF Downloads 422745 Nursing System Development in Patients Undergoing Operation in 3C Ward: Early Ambulation in Patients with Head and Neck Cancer
Authors: Artitaya Sabangbal, Darawan Augsornwan, Palakorn Surakunprapha, Lalida Petphai
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Background: Srinagarind Hospital Ward 3C has about 180 cases of patients with head and neck cancer per year. Almost all of these patients suffer with pain, fatigue, low self image, swallowing problem and when the tumor is larger they will have breathing problem. Many of them have complication after operation such as pressure sore, pneumonia, deep vein thrombosis. Nursing activity is very important to prevent the complication especially promoting patients early ambulation. The objective of this study was to develop early ambulation protocol for patients with head and neck cancer undergoing operation. Method: this study is one part of nursing system development in patients undergoing operation in Ward 3C. It is a participation action research divided into 3 phases Phase 1 Situation review: In this phase we review the clinical outcomes, process of care, from document such as nurses note and interview nurses, patients and family about early ambulation. Phase 2 Searching nursing intervention about early ambulation from previous study then establish protocol . This phase we have picture package of early ambulation. Phase 3 implementation and evaluation. Result: Patients with head and neck cancer after operation can follow early ambulation protocol 100%, 85 % of patients can follow protocol within 2 days after operation and 100% can follow protocol within 3 days. No complications occur. Patients satisfaction in very good level is 58% and in good level is 42% Length of hospital stay is 6 days in patients with wide excision and 16 day in patients with flap coverage. Conclusion: The early ambulation protocol is appropriate for patients with head and neck cancer who undergo operation. This can restore physical health, reduce complication and increase patients satisfaction.Keywords: nursing system, early ambulation, head and neck cancer, operation
Procedia PDF Downloads 217744 A Study on Hierarchy and Popularity of Foreign TV Series with Different Origin Countries among Chinese Audiences from a Uses and Gratification Perspective
Authors: Terigele
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Cultural products are always shelved into different classes of a hierarchy that separates so-called highbrow and lowbrow cultures. This study illustrated that audiences might even construct a hierarchy according to the origin countries when consuming certain products. Chinese audiences now have access to TV series from all around the world thanks to the internet. TV series from different origin countries show some particular features in terms of length, theme, plots, accessibility, seriousness etc. Their audiences were therefore stereotyped because of what they watch. Based on in-depth interviews with 20 participants, this research has following findings: 1) Most popular origin countries of foreign TV series in China are Korea, the United States, the United Kingdom, Japan and European countries in a descending order. Korean TV series are most popular because they are less serious and more accessible compared to others. 2) In the hierarchy of the TV series, European TV series stand on the top followed by British and American TV series. Japanese TV series are also categorized into highbrow class. Korean TV series are at the bottom and always seen as lowbrow cultural products. 3) Most audiences consume TV series from more than one origin countries and have different needs when watching them. Participants reported that they watch European TV series because those TV series are more artistic than their counterparts and of great quality. They watch British and American TV series mainly to improve their English and to learn about the culture. They find Japanese TV series very enjoyable with a large variety of themes and impressive lines. Audiences watch Korean TV series mostly to entertain and kill time. 4) Audiences do care about cultural taste. Especially those who watch European, British and American TV series usually tend to consider audiences who watch nothing but Korean TV series to be shallow. On the other hand, Korean TV series’ audiences seem to care less about the hierarchy of the TV series. Even when they discuss the hierarchy, they tend to accept the judgments with ironies and jokes. Future studies can dig deeply into the genre and content of TV series with different origin countries and also investigate more about the psychology of audiences regarding the gender, age, education, socioeconomic status etc.Keywords: foreign TV series, hierarchy, popularity, uses and gratification
Procedia PDF Downloads 236743 Performance Evaluation of Cement Mortar with Crushed Stone Dust as Fine Aggregates
Authors: Pradeep Kumar
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The present work is based on application of cement mortar with natural sand and discontinuous steel fiber through which bending behavior of skinny beam was evaluated. This research is to study the effects of combining reinforcing steel meshes (continuous steel reinforcement) with discontinuous fibers as reinforcement in skinny walled Portland cement based cement mortar with crushed stone dust as a fine aggregate. The term ‘skinny’ means thickness of the beams is less than 25 mm. The main idea behind this combination is to satisfy the ultimate strength limit state through the steel mesh reinforcement (as a main reinforcement) and to control the cracking under service loads through fiber (Recron 3s) reinforcement (as secondary reinforcement). The main object of this study is to carry out the bending behavior of mortar reinforced thin beam with only one layer of steel mesh (with various transfer wire spacing) and with a recron 3s (Reliance) fifers. The wide experimental program with bending tests is undertaken. The following variables are investigated: (a) the reference mesh size - 25.4 x 25.4 mm and 50.8 x 50.8 mm; (b) the transverse wire spacing - 25.4 mm, 50.8 mm, and no transverse wires; (c) the type of fibers – Reliance (Recron 3s, 6mm length); and (d) the fiber volume fraction – 0.1% and 0.25%. Some of the main conclusions are: (a) the use of recron 3s fibers leads to a little better overall performance than that with no fiber; (b) an increase in equivalent stress is observed when 0.1% RF,0.25% R Fibers are used; (c) when 25.4 x 50.8 size steel mesh is used, no noticeable change in behavior is observed in comparison to specimens without fibers; and (d) for no fibers 0.1% and o.1% RF the transverse wire spacing has some little effect on the equivalent stress for RF fibers, the transverse wire has no influence but the equivalent stress are increased.Keywords: cement mortar, crushed stone dust, fibre, steel mesh
Procedia PDF Downloads 303742 The Acute Effects of Higher Versus Lower Load Duration and Intensity on Morphological and Mechanical Properties of the Healthy Achilles Tendon: A Randomized Crossover Trial
Authors: Eman Merza, Stephen Pearson, Glen Lichtwark, Peter Malliaras
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The Achilles tendon (AT) exhibits volume changes related to fluid flow under acute load which may be linked to changes in stiffness. Fluid flow provides a mechanical signal for cellular activity and may be one mechanism that facilitates tendon adaptation. This study aimed to investigate whether isometric intervention involving a high level of load duration and intensity could maximize the immediate reduction in AT volume and stiffness compared to interventions involving a lower level of load duration and intensity. Sixteen healthy participants (12 males, 4 females; age= 24.4 ± 9.4 years; body mass= 70.9 ± 16.1 kg; height= 1.7 ± 0.1 m) performed three isometric interventions of varying levels of load duration (2 s and 8 s) and intensity (35% and 75% maximal voluntary isometric contraction) over a 3 week period. Freehand 3D ultrasound was used to measure free AT volume (at rest) and length (at 35%, 55%, and 75% of maximum plantarflexion force) pre- and post-interventions. The slope of the force-elongation curve over these force levels represented individual stiffness (N/mm). Large reductions in free AT volume and stiffness resulted in response to long-duration high-intensity loading whilst less reduction was produced with a lower load intensity. In contrast, no change in free AT volume and a small increase in AT stiffness occurred with lower load duration. These findings suggest that the applied load on the AT must be heavy and sustained for a long duration to maximize immediate volume reduction, which might be an acute response that enables optimal long-term tendon adaptation via mechanotransduction pathways.Keywords: Achilles tendon, volume, stiffness, free tendon, 3d ultrasound
Procedia PDF Downloads 86741 Effect of Fiddler Crab Burrows on Bacterial Communities of Mangrove Sediments
Authors: Mohammad Mokhtari, Gires Usup, Zaidi Che Cob
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Bacteria communities as mediators of the biogeochemical process are the main component of the mangrove ecosystems. Crab burrows by increasing oxic-anoxic interfaces and facilitating the flux rate between sediment and tidal water affect biogeochemical properties of sediments. The effect of fiddler crab burrows on the density and diversity of bacteria were investigated to elucidate the effect of burrow on bacterial distribution. Samples collected from the burrow walls of three species of fiddler crabs including Uca paradussumieri, Uca rosea, and Uca forcipata. Sediment properties including grain size, temperature, Redox potential, pH, chlorophyll, water and organic content were measured from the burrow walls to assess the correlation between environmental variables and bacterial communities. Bacteria were enumerated with epifluorescence microscopy after staining with SYBR green. Bacterial DNA extracted from sediment samples and the community profiles of bacteria were determined with Terminal Restriction Fragment Length Polymorphism (T-RFLP). High endemism was observed among bacterial communities. Among the 152 observed OTU’s, 22 were found only in crab burrows. The highest bacterial density and diversity were recorded in burrow wall. The results of ANOSIM indicated a significant difference between the bacterial communities from the three species of fiddler crab burrows. Only 3% of explained bacteria variability in the constrained ordination model of CCA was contributed to depth, while much of the bacteria’s variability was attributed to coarse sand, pH, and chlorophyll content. Our findings suggest that crab burrows by affecting sediment properties such as redox potential, pH, water, and chlorophyll content induce significant effects on the bacterial communities.Keywords: bioturbation, canonical corresponding analysis, fiddler crab, microbial ecology
Procedia PDF Downloads 146740 Plastic Pellets in Santa Cruz Dos Navegantes Beach, Brazil, in the Winter of 2019
Authors: Victor Vasques Ribeiro
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The Santa Cruz dos Navegantes beach is located in the city of Guarujá, in the central portion of the coast of the state of São Paulo. Next to this beach is located the Channel of the Port of Santos, configured as a source of plastic pellets for marine environments. On sandy beaches near the sources, especially during the winter and after cold front entrance events, the amounts of pellets can be very high. This study aimed to determine the influence of a cold front entry event of the winter of 2019 on the amount of pellets found on Santa Cruz dos Navegantes beach, besides assuming the proximity of the sources. During six consecutive collection campaigns, three of which were previous and three after the cold front entry peak, 30.0 square meters of surface sediments were sampled in each campaign. The color and shape of the pellets were determined to assume the length of the permanence of these granules in the marine environment and, consequently, the proximity of the sources. This beach was considered ideal for this type of research. The pellet pollution index (PPI) was from moderate to very high right after the peak of the cold front entry. The cold front peak event significantly influenced the amount of pellets found on the beach of Santa Cruz dos Navegantes. The factors that can bury the pellets in the sediments were classified as low when compared to other beaches in the region. Most of the pellets found were recently produced and lost to aquatic environments. Like the other beaches near Santos Bay, Santa Cruz dos Navegantes beach receives significant amounts of pellets that have nearby origins. Therefore, it was supposed that the activities of the Santos port complex are sources of pellets for the marine environment. This pollution can be further worsened in certain meteoceanographic events. The beaches of this region need to be constantly monitored and evaluated for pollution by pellets.Keywords: beach, cold front, pellets, sources
Procedia PDF Downloads 180739 Determinants of Consultation Time at a Family Medicine Center
Authors: Ali Alshahrani, Adel Almaai, Saad Garni
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Aim of the study: To explore duration and determinants of consultation time at a family medicine center. Methodology: This study was conducted at the Family Medicine Center in Ahad Rafidah City, at the southwestern part of Saudi Arabia. It was conducted on the working days of March 2013. Trained nurses helped in filling in the checklist. A total of 459 patients were included. A checklist was designed and used in this study. It included patient’s age, sex, diagnosis, type of visit, referral and its type, psychological problems and additional work-up. In addition, number of daily bookings, physician`s experience and consultation time. Results: More than half of patients (58.39%) had less than 10 minutes’ consultation (Mean+SD: 12.73+9.22 minutes). Patients treated by physicians with shortest experience (i.e., ≤5 years) had the longest consultation time while those who were treated with physicians with the longest experience (i.e., > 10 years) had the shortest consultation time (13.94±10.99 versus 10.79±7.28, p=0.011). Regarding patients’ diagnosis, those with chronic diseases had the longest consultation time (p<0.001). Patients who did not need referral had significantly shorter consultation time compared with those who had routine or urgent referral (11.91±8.42,14.60±9.03 and 22.42±14.81 minutes, respectively, p<0.001). Patients with associated psychological problems needed significantly longer consultation time than those without associated psychological problems (20.06±13.32 versus 12.45±8.93, p<0.001). Conclusions: The average length of consultation time at Ahad Rafidah Family Medicine Center is approximately 13 minutes. Less-experienced physicians tend to spend longer consultation times with patients. Referred patients, those with psychological problems, those with chronic diseases tend to have longer consultation time. Recommendations: Family physicians should be encouraged to keep their optimal consultation time. Booking an adequate number of patients per shift would allow the family physician to provide enough consultation time for each patient.Keywords: consultation, quality, medicine, clinics
Procedia PDF Downloads 278738 Metagenomics-Based Molecular Epidemiology of Viral Diseases
Authors: Vyacheslav Furtak, Merja Roivainen, Olga Mirochnichenko, Majid Laassri, Bella Bidzhieva, Tatiana Zagorodnyaya, Vladimir Chizhikov, Konstantin Chumakov
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Molecular epidemiology and environmental surveillance are parts of a rational strategy to control infectious diseases. They have been widely used in the worldwide campaign to eradicate poliomyelitis, which otherwise would be complicated by the inability to rapidly respond to outbreaks and determine sources of the infection. The conventional scheme involves isolation of viruses from patients and the environment, followed by their identification by nucleotide sequences analysis to determine phylogenetic relationships. This is a tedious and time-consuming process that yields definitive results when it may be too late to implement countermeasures. Because of the difficulty of high-throughput full-genome sequencing, most such studies are conducted by sequencing only capsid genes or their parts. Therefore the important information about the contribution of other parts of the genome and inter- and intra-species recombination to viral evolution is not captured. Here we propose a new approach based on the rapid concentration of sewage samples with tangential flow filtration followed by deep sequencing and reconstruction of nucleotide sequences of viruses present in the samples. The entire nucleic acids content of each sample is sequenced, thus preserving in digital format the complete spectrum of viruses. A set of rapid algorithms was developed to separate deep sequence reads into discrete populations corresponding to each virus and assemble them into full-length consensus contigs, as well as to generate a complete profile of sequence heterogeneities in each of them. This provides an effective approach to study molecular epidemiology and evolution of natural viral populations.Keywords: poliovirus, eradication, environmental surveillance, laboratory diagnosis
Procedia PDF Downloads 270737 Damage Identification in Reinforced Concrete Beams Using Modal Parameters and Their Formulation
Authors: Ali Al-Ghalib, Fouad Mohammad
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The identification of damage in reinforced concrete structures subjected to incremental cracking performance exploiting vibration data is recognized as a challenging topic in the published and heavily cited literature. Therefore, this paper attempts to shine light on the extent of dynamic methods when applied to reinforced concrete beams simulated with various scenarios of defects. For this purpose, three different reinforced concrete beams are tested through the course of the study. The three beams are loaded statically to failure in incremental successive load cycles and later rehabilitated. After each static load stage, the beams are tested under free-free support condition using experimental modal analysis. The beams were all of the same length and cross-sectional area (2.0x0.14x0.09)m, but they were different in concrete compressive strength and the type of damage presented. The experimental modal parameters as damage identification parameters were showed computationally expensive, time consuming and require substantial inputs and considerable expertise. Nonetheless, they were proved plausible for the condition monitoring of the current case study as well as structural changes in the course of progressive loads. It was accentuated that a satisfactory localization and quantification for structural changes (Level 2 and Level 3 of damage identification problem) can only be achieved reasonably through considering frequencies and mode shapes of a system in a proper analytical model. A convenient post analysis process for various datasets of vibration measurements for the three beams is conducted in order to extract, check and correlate the basic modal parameters; namely, natural frequency, modal damping and mode shapes. The results of the extracted modal parameters and their combination are utilized and discussed in this research as quantification parameters.Keywords: experimental modal analysis, damage identification, structural health monitoring, reinforced concrete beam
Procedia PDF Downloads 254736 Analysis of a Damage-Control Target Displacement of Reinforced Concrete Bridge Pier for Seismic Design
Authors: Mohd Ritzman Abdul Karim, Zhaohui Huang
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A current focus in seismic engineering practice is the development of seismic design approach that focuses on the performance-based design. Performance-based design aims to design the structures to achieve specified performance based on the damage limit states. This damage limit is more restrictive limit than life safety and needs to be carefully estimated to avoid damage in piers due to failure in transverse reinforcement. In this paper, a different perspective of damage limit states has been explored by integrating two damage control material limit state, concrete and reinforcement by introduced parameters such as expected yield stress of transverse reinforcement where peak tension strain prior to bar buckling is introduced in a recent study. The different perspective of damage limit states with modified yield displacement and the modified plastic-hinge length is used in order to predict damage-control target displacement for reinforced concreate (RC) bridge pier. Three-dimensional (3D) finite element (FE) model has been developed for estimating damage target displacement to validate proposed damage limit states. The result from 3D FE analysis was validated with experimental study found in the literature. The validated model then was applied to predict the damage target displacement for RC bridge pier and to validate the proposed study. The tensile strain on reinforcement and compression on concrete were used to determine the predicted damage target displacement and compared with the proposed study. The result shows that the proposed damage limit states were efficient in predicting damage-control target displacement consistent with FE simulations.Keywords: damage-control target displacement, damage limit states, reinforced concrete bridge pier, yield displacement
Procedia PDF Downloads 148735 Gap Formation into Bulk InSb Crystals Grown by the VDS Technique Revealing Enhancement in the Transport Properties
Authors: Dattatray Gadkari, Dilip Maske, Manisha Joshi, Rashmi Choudhari, Brij Mohan Arora
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The vertical directional solidification (VDS) technique has been applied to the growth of bulk InSb crystals. The concept of practical stability is applied to the case of detached bulk crystal growth on earth in a simplified design. By optimization of the set up and growth parameters, 32 ingots of 65-75 mm in length and 10-22 mm in diameter have been grown. The results indicate that the wetting angle of the melt on the ampoule wall and the pressure difference across the interface are the crucial factors effecting the meniscus shape and stability. Taking into account both heat transfer and capillarity, it is demonstrated that the process is stable in case of convex menisci (seen from melt), provided that pressure fluctuations remain in a stable range. During the crystal growth process, it is necessary to keep a relationship between the rate of the difference pressure controls and the solidification to maintain the width of gas gap. It is concluded that practical stability gives valuable knowledge of the dynamics and could be usefully applied to other crystal growth processes, especially those involving capillary shaping. Optoelectronic properties were investigated in relation to the type of solidification attached and detached ingots growth. These samples, room temperature physical properties such as Hall mobility, FTIR, Raman spectroscopy and microhardness achieved for antimonide samples grown by VDS technique have shown the highest values gained till at this time. These results reveal that these crystals can be used to produce InSb with high mobility for device applications.Keywords: alloys, electronic materials, semiconductors, crystal growth, solidification, etching, optical microscopy, crystal structure, defects, Hall effect
Procedia PDF Downloads 409734 Investigation of Boll Properties on Cotton Picker Machine Performance
Authors: Shahram Nowrouzieh, Abbas Rezaei Asl, Mohamad Ali Jafari
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Cotton, as a strategic crop, plays an important role in providing human food and clothing need, because of its oil, protein, and fiber. Iran has been one of the largest cotton producers in the world in the past, but unfortunately, for economic reasons, its production is reduced now. One of the ways to reduce the cost of cotton production is to expand the mechanization of cotton harvesting. Iranian farmers do not accept the function of cotton harvesters. One reason for this lack of acceptance of cotton harvesting machines is the number of field losses on these machines. So, the majority of cotton fields are harvested by hand. Although the correct setting of the harvesting machine is very important in the cotton losses, the morphological properties of the cotton plant also affect the performance of cotton harvesters. In this study, the effect of some cotton morphological properties such as the height of the cotton plant, number, and length of sympodial and monopodial branches, boll dimensions, boll weight, number of carpels and bracts angle were evaluated on the performance of cotton picker. In this research, the efficiency of John Deere 9920 spindle Cotton picker is investigated on five different Iranian cotton cultivars. The results indicate that there was a significant difference between the five cultivars in terms of machine harvest efficiency. Golestan cultivar showed the best cotton harvester performance with an average of 87.6% of total harvestable seed cotton and Khorshid cultivar had the least cotton harvester performance. The principal component analysis showed that, at 50.76% probability, the cotton picker efficiency is affected by the bracts angle positively and by boll dimensions, the number of carpels and the height of cotton plants negatively. The seed cotton remains (in the plant and on the ground) after harvester in PCA scatter plot were in the same zone with boll dimensions and several carpels.Keywords: cotton, bract, harvester, carpel
Procedia PDF Downloads 129733 Optimizing Bridge Deck Construction: A Deep Neural Network Approach for Limiting Exterior Grider Rotation
Authors: Li Hui, Riyadh Hindi
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In the United States, bridge construction often employs overhang brackets to support the deck overhang, the weight of fresh concrete, and loads from construction equipment. This approach, however, can lead to significant torsional moments on the exterior girders, potentially causing excessive girder rotation. Such rotations can result in various safety and maintenance issues, including thinning of the deck, reduced concrete cover, and cracking during service. Traditionally, these issues are addressed by installing temporary lateral bracing systems and conducting comprehensive torsional analysis through detailed finite element analysis for the construction of bridge deck overhang. However, this process is often intricate and time-intensive, with the spacing between temporary lateral bracing systems usually relying on the field engineers’ expertise. In this study, a deep neural network model is introduced to limit exterior girder rotation during bridge deck construction. The model predicts the optimal spacing between temporary bracing systems. To train this model, over 10,000 finite element models were generated in SAP2000, incorporating varying parameters such as girder dimensions, span length, and types and spacing of lateral bracing systems. The findings demonstrate that the deep neural network provides an effective and efficient alternative for limiting the exterior girder rotation for bridge deck construction. By reducing dependence on extensive finite element analyses, this approach stands out as a significant advancement in improving safety and maintenance effectiveness in the construction of bridge decks.Keywords: bridge deck construction, exterior girder rotation, deep learning, finite element analysis
Procedia PDF Downloads 55732 Performance Analysis of Modified Solar Water Heating System for Climatic Condition of Allahabad, India
Authors: Kirti Tewari, Rahul Dev
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Solar water heating is a thermodynamic process of heating water using sunlight with the help of solar water heater. Thus, solar water heater is a device used to harness solar energy. In this paper, a modified solar water heating system (MSWHS) has been proposed over flat plate collector (FPC) and Evacuated tube collector (ETC). The modifications include selection of materials other than glass, and glass wool which are conventionally used for fabricating FPC and ETC. Some modifications in design have also been proposed. Its collector is made of double layer of semi-cylindrical acrylic tubes and fibre reinforced plastic (FRP) insulation base. Water tank is made of double layer of acrylic sheet except base and north wall. FRP is used in base and north wall of the water tank. A concept of equivalent thickness has been utilised for calculating the dimensions of collector plate, acrylic tube and tank. A thermal model for the proposed design of MSWHS is developed and simulation is carried out on MATLAB for the capacity of 200L MSWHS having collector area of 1.6 m2, length of acrylic tubes of 2m at an inclination angle 25° which is taken nearly equal to the latitude of the given location. Latitude of Allahabad is 24.45° N. The results show that the maximum temperature of water in tank and tube has been found to be 71.2°C and 73.3°C at 17:00hr and 16:00hr respectively in March for the climatic data of Allahabad. Theoretical performance analysis has been carried out by varying number of tubes of collector, the tank capacity and climatic data for given months of winter and summer.Keywords: acrylic, fibre reinforced plastic, solar water heating, thermal model, conventional water heaters
Procedia PDF Downloads 330731 Temperature Dependent Current-Voltage (I-V) Characteristics of CuO-ZnO Nanorods Based Heterojunction Solar Cells
Authors: Venkatesan Annadurai, Kannan Ethirajalu, Anu Roshini Ramakrishnan
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Copper oxide (CuO) and zinc oxide (ZnO) based coaxial (CuO-ZnO nanorods) heterojunction has been the interest of various research communities for solar cells, light emitting diodes (LEDs) and photodetectors applications. Copper oxide (CuO) is a p-type material with the band gap of 1.5 eV and it is considered to be an attractive absorber material in solar cells applications due to its high absorption coefficient and long minority carrier diffusion length. Similarly, n-type ZnO nanorods possess many attractive advantages over thin films such as, the light trapping ability and photosensitivity owing to the presence of oxygen related hole-traps at the surface. Moreover, the abundant availability, non-toxicity, and inexpensiveness of these materials make them suitable for potentially cheap, large area, and stable photovoltaic applications. However, the efficiency of the CuO-ZnO nanorods heterojunction based devices is greatly affected by interface defects which generally lead to the poor performance. In spite of having much potential, not much work has been carried out to understand the interface quality and transport mechanism involved across the CuO-ZnO nanorods heterojunction. Therefore, a detailed investigation of CuO-ZnO heterojunction is needed to understand the interface which affects its photovoltaic performance. Herein, we have fabricated the CuO-ZnO nanorods based heterojunction by simple hydrothermal and electrodeposition technique and investigated its interface quality by carrying out temperature (300 –10 K) dependent current-voltage (I-V) measurements under dark and illumination of visible light. Activation energies extracted from the temperature dependent I-V characteristics reveals that recombination and tunneling mechanism across the interfacial barrier plays a significant role in the current flow.Keywords: heterojunction, electrical transport, nanorods, solar cells
Procedia PDF Downloads 217730 Endophytic Fungi Recovered from Lycium arabicum as an Eco-Friendly Alternative for Fusarium Crown and Root Rot Disease Control and Tomato Growth Enhancement
Authors: Ahlem Nefzi, Rania Aydi Ben Abdallah, Hayfa Jabnoun-Khiareddine, Ammar Nawaim, Rabiaa Haouala, Mejda Daami-Remadi
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Seven endophytic fungi were isolated from the wild Solanaceous species Lycium arabicum growing in the Tunisian Centre-East and were assessed for their ability to suppress Fusarium Crown and Root Rot disease caused by Fusarium oxysporum f. sp. radicis lycopersici (FORL) and to enhance plant growth. Fungal isolates were shown able to colonize tomato cv. Rio Grande roots, crowns, and stems. A significant promotion in all studied growth parameters (root length, shoot height, and roots and shoots fresh weight) was recorded in tomato plants treated with fungal conidial suspensions or their cell-free culture filtrates compared to FORL-inoculated or pathogen-free controls. I15 and I18 isolates were shown to be the most effective leading to 85.7-87.5 and 93.6-98.4% decrease in leaf and root damage index and the vascular discoloration extent, respectively, over FORL-inoculated and untreated control. These two bioactive and growth-promoting isolates (I15 and I18) were morphologically characterized and identified using rDNA sequencing gene as being Alternaria alternata (MF693801) and Fusarium fujikuroi (MF693802). These fungi significantly suppressed FORL mycelial growth and showed chitinolytic, proteolytic and amylase activities whereas only F. fujikuroi displayed a lipolytic activity. This study clearly demonstrated the potential use of fungi naturally associated with L. arabicum as biocontrol and bio-fertilizing agents.Keywords: biocontrol, endophytic fungi, Fusarium oxysporum f. sp. radicis-lycopersici, tomato promotion, Lycium arabicum
Procedia PDF Downloads 165