Search results for: maximum pressure

Authors: Fatma Ünal, Hasancan Okutan

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Increasing worldwide population and technological requirements lead to an increase in energy demand every year. The demand has been mainly supplied from fossil fuels such as coal and petroleum due to insufficient natural gas resources. In recent years, the amount of coal reserves has reached almost 21 billion tons in Türkiye. These are mostly lignite (%92,7), that contains high levels of moisture and sulfur components. Underground coal gasification technology is one of the most suitable methods in comparison with direct combustion techniques for the evaluation of such coal types. In this study, the applicability of the underground coal gasification process is investigated in the Eskişehir-Alpu lignite reserve as a pilot region, both technologically and economically. It is assumed that the electricity is produced from the obtained synthesis gas in an integrated gasification combined cycle (IGCC). Firstly, an equilibrium model has been developed by using the thermodynamic properties of the gasification reactions. The effect of the type of oxidizing gas, the sulfur content of coal, the rate of water vapor/air, and the pressure of the system have been investigated to find optimum process conditions. Secondly, the parallel and linear controlled recreation and injection point (CRIP) models were implemented as drilling methods, and costs were calculated under the different oxidizing agents (air and high-purity O2). In Parallel CRIP (P-CRIP), drilling cost is found to be lower than the linear CRIP (L-CRIP) since two coal beds simultaneously are gasified. It is seen that CO2 Capture and Storage (CCS) technology was the most effective unit on the total cost in both models. The cost of the synthesis gas produced varies between 0,02 $/Mcal and 0,09 $/Mcal. This is the promising result when considering the selling price of Türkiye natural gas for Q1-2023 (0.103 $ /Mcal).

Keywords: energy, lignite reserve, techno-economic analysis, underground coal gasification.

Procedia PDF Downloads 67

Authors: Richard G. Boakye, Dara A Stanley, Mathavan Vickneswaran, Blanaid White

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The cultivation of cocoa (Theobroma cocoa), an important cash crop that contributes immensely towards the economic growth of several Western African countries, depends almost entirely on pesticide application owing to the plant’s vulnerability to pest and disease attacks. However, the extent to which pesticides inputted for cocoa cultivation impact bees and bee products has rarely received attention in research. Through this study, the effects of pesticides applied for cocoa cultivation on honey in Ghana were examined by evaluating honey samples from cocoa and forest ecosystems in Ghana. An analysis of five honey samples from each land use type confirmed pesticide contaminants from these land use types at measured concentrations for acetamiprid (0.051mg/kg); imidacloprid (0.004-0.02 mg/kg), thiamethoxam (0.013-0.017 mg/kg); indoxacarb (0.004-0.045 mg/kg) and sulfoxaflor (0.004-0.026 mg/kg). None of the observed pesticide concentrations exceeded EU maximum residue levels, indicating no compromise of the honey quality for human consumption. However, from the results, it could be inferred that toxic effects on bees may not be ruled out because observed concentrations largely exceeded the threshold of 0.001 mg/kg at which sublethal effects on bees have previously been reported. One of the most remarkable results to emerge from this study is the detection of imidacloprid in all honey samples analyzed, with sulfoxaflor and thiamethoxam also being detected in 93% and 73% of the honey samples, respectively. This suggests the probable prevalence of pesticide use in the landscape. However, the conclusions reached in this study should be interpreted within the scope of pesticide applications within Bia West District and not necessarily extended to other cocoa-producing districts in Ghana. Future studies should therefore include multiple cocoa-growing districts and other non-cocoa farming landscapes. Such an approach can give a broader outlook on pesticide residues in honey produced in Ghana.

Keywords: honey, cocoa, pesticides, bees, land use, landscape, residues, Ghana

Procedia PDF Downloads 81

Authors: Mohamed H. Khalifa, Fikry I. El-Shahawi, Nabil A. Mansour

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The cotton leafworm, Spodoptera littoralis (Boisduval) is a major insect pest of vegetables and cotton crops in Egypt, and exhibits different levels of tolerance to certain insecticides. Chlorantraniliprole has been registered recently in Egypt for control this insect. The susceptibilities of three S. littoralis populations collected from El Behaira governorate, north Egypt to chlorantraniliprole were determined by leaf-dipping technique on 4^th instar larvae. Obvious variation of toxicity was observed among the laboratory susceptible, and three field populations with LC₅₀ values ranged between 1.53 µg/ml and 6.22 µg/ml. However, all the three field populations were less susceptible to chlorantraniliprole than a laboratory susceptible population. The most tolerant populations were sampled from El Delengat (ED) Province where S. littoralis had been frequently challenged by insecticides. Certain enzyme activity assays were carried out to be correlated with the mechanism of the observed field population tolerance. All field populations showed significantly enhanced activities of detoxification enzymes compared with the susceptible strain. The regression analysis between chlorantraniliprole toxicities and enzyme activities revealed that the highest correlation is between α-esterase or β-esterase (α-β-EST) activity and collected field strains susceptibility, otherwise this correlation is not significant (P > 0.05). Synergism assays showed the ED and susceptible strains could be synergized by known detoxification inhibitors such as piperonyl butoxide (PBO), triphenyl phosphate (TPP) and diethyl-maleate (DEM) at different levels (1.01-8.76-fold and 1.09-2.94 fold, respectively), TPP showed the maximum synergism in both strains. The results show that there is a correlation between the enzyme activity and tolerance, and carboxylic-esterase (Car-EST) is likely the main detoxification mechanism responsible for tolerance of S. littoralis to chlorantraniliprole.

Keywords: chlorantraniliprole, detoxification enzymes, Egypt, Spodoptera littoralis

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Authors: Mahesh Kumar Jat, Manisha Choudhary

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Rapid population and economic growth resulted in changes in large-scale land use land cover (LULC) changes. Changes in the biophysical properties of the Earth's surface and its impact on climate are of primary concern nowadays. Different approaches, ranging from location-based relationships or modelling earth surface - atmospheric interaction through modelling techniques like surface energy balance (SEB) have been used in the recent past to examine the relationship between changes in Earth surface land cover and climatic characteristics like temperature and precipitation. A remote sensing-based model i.e., Surface Energy Balance Algorithm for Land (SEBAL), has been used to estimate the surface heat fluxes over Mahi Bajaj Sagar catchment (India) from 2001 to 2020. Landsat ETM and OLI satellite data are used to model the SEB of the area. Changes in observed precipitation and temperature, obtained from India Meteorological Department (IMD) have been correlated with changes in surface heat fluxes to understand the relative contributions of LULC change in changing these climatic variables. Results indicate a noticeable impact of LULC changes on climatic variables, which are aligned with respective changes in SEB components. Results suggest that precipitation increases at a rate of 20 mm/year. The maximum and minimum temperature decreases and increases at 0.007 ℃ /year and 0.02 ℃ /year, respectively. The average temperature increases at 0.009 ℃ /year. Changes in latent heat flux and sensible heat flux positively correlate with precipitation and temperature, respectively. Variation in surface heat fluxes influences the climate parameters and is an adequate reason for climate change. So, SEB modelling is helpful to understand the LULC change and its impact on climate.

Keywords: remote sensing, GIS, object based, classification

Procedia PDF Downloads 130

Authors: Rida Batool, Faizah Altaf, Saba Nadeem, Afifa Aslam, Faisal Alamgir, Ghazanfar Abbas

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Today, the need of the hour is to find out alternative renewable energy resources in order to reduce the burden on fossil fuels and prevent alarming environmental degradation. Solid oxide fuel cell (SOFC) is considered a good alternative energy conversion device because it is environmentally benign and supplies energy on demand. The only drawback associated with SOFC is its high operating temperature. In order to reduce operating temperature, different types of composite material are prepared. In this work, titanium doped lanthanum gallium cerate (LGCT) composite is prepared through the co-precipitation method as electrolyte and examined for low temperature SOFCs (LTSOFCs). The structural properties are analyzed by X-Ray Diffractometry (XRD) and Fourier Transform Infrared (FTIR) Spectrometry. The surface properties are investigated by Scanning Electron Microscopy (SEM). The electrolyte LGCT has the formula LGCTO₃ because it showed two phases La.GaO and Ti.CeO₂. The average particle size is found to be (32 ± 0.9311) nm. The ionic conductivity is achieved to be 0.073S/cm at 650°C. Arrhenius plots are drawn to calculate activation energy and found 2.96 eV. The maximum power density and current density are achieved at 68.25mW/cm² and 357mA/cm², respectively, at 650°C with hydrogen. The prepared material shows excellent ionic conductivity at comparatively low temperature, that makes it a potentially good candidate for LTSOFCs.

Keywords: solid oxide fuel cell, LGCTO₃, cerium composite oxide, ionic conductivity, low temperature electrolyte

Procedia PDF Downloads 108

Authors: Farshid Marbouti, Jale Ulas, Julia Thompson

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The main sources of stress among college students are: changes in sleeping and eating habits, undertaking new responsibilities, and financial difficulties as the most common sources of stress, exams, meeting new people, career decisions, fear of failure, and pressure from parents, transition to university especially if it requires leaving home, working with people that they do not know, trouble with parents, and relationship with the opposite sex. The students use a variety of stress coping strategies, including talking to family and friends, leisure activities and exercising. The Yerkes–Dodson law indicates while a moderate amount of stress may be beneficial for performance, too high stress will result in weak performance. In other words, if students are too stressed, they are likely to have low academic performance. In a preliminary study conducted in 2017 with engineering students enrolled in three high failure rate classes, the majority of the students stated that they have high levels of stress mainly for academic, financial, or family-related reasons. As the second stage of the study, the main purpose of this research is to investigate the students’ level of stress, sources of stress, their relationship with student demographic background, students’ coping strategies, and academic performance. A device is being developed to gather data from students breathing patterns and measure their stress levels. In addition, all participants are asked to fill out a survey. The survey under development has the following categories: exam stressor, study-related stressors, financial pressures, transition to university, family-related stress, student response to stress, and stress management. After the data collection, Structural Equation Modeling (SEM) analysis will be conducted in order to identify the relationship among students’ level of stress, coping strategies, and academic performance.

Keywords: college student stress, coping strategies, academic performance, measuring stress

Procedia PDF Downloads 104

Authors: Hasan Izhar Khan, Naiqiang Zhang, Hong Xu, Zhongliang Zhu, Dongfang Jiang

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Inconel 625 is a nickel-based alloy having outstanding corrosion resistance and developed for use at service temperatures ranging from cryogenic to 980°C. It got a wide range of applications in nuclear, petrochemical, chemical, marine, aeronautical, and aerospace industries. Currently, it is one of the candidate materials to be used as a structural material in ultra-supercritical (USC) power plants. In the high-temperature corrosive medium environment, metallic materials are susceptible to corrosion fatigue (CF). CF is an interaction between cyclic stress and corrosive medium environment that acts on a susceptible material and results in initiation and propagation of cracks. For the application of Inconel 625 as a structural material in USC power plants, CF behavior must be evaluated in steam and supercritical water (SCW) environment. Fatigue crack growth rate (FCGR) curves obtained from CF experiments are required to predict residual life of metallic materials used in power plants. In this study, FCGR tests of Inconel 625 were obtained by using compact tension specimen at 550-650 °C in steam (8 MPa) and SCW (25 MPa). The dissolved oxygen level was kept constant at 8000 ppb for the test conducted in steam and SCW. The tests were performed under sine wave loading waveform, 1 Hz loading frequency, stress ratio of 0.6 and maximum stress intensity factor of 32 MPa√m. Crack growth rate (CGR) was detected by using direct current potential drop technique. Results showed that CGR increased with an increase in temperature in the tested environmental conditions. The mechanism concerning the influence of temperature on FCGR are further discussed.

Keywords: corrosion fatigue, crack growth rate, nickel-based alloy, temperature

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Authors: Amir Ali, Laura Yael Mendoza

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The application of nanomaterials is becoming the most effective strategy of elicitation to produce a desirable level of plant biomass with complex medicinal compounds. This study was designed to check the influence of phytosynthesized iron nanoparticles (FeNPs) on physical growth characteristics, antioxidant status, and production of steviol glycosides of in vitro grown Stevia rebaudiana. Effect of different concentrations of iron nanoparticles replacement of iron sulfate in MS medium (stock solution) on invitro stevia plant growth following positive control (MS basal medium), negative control (iron sulfate devoid medium), iron sulfate devoid MS medium and supplemented with FeNPs at different concentrations (5.6 mg/L, 11.2 mg/L, 16.8 mg/L, 22.4 mg/L) was evaluated. The iron deficiency leads to a drastic reduction in plant growth. In contrast, applying FeNPs leads to improvement in plant height, leave diameter, improved leave morphology, etc., in a concentration-dependent manner. Furthermore, the stress caused by FeNPs at 16.8 mg/L in cultures produced higher levels of total phenolic content (3.7 ± 0.042 mg/g dry weight: DW) and total flavonoid content (1.9 ± 0.022 mg/g DW and antioxidant activity (78 ± 4.6%). In addition, plants grown in the presence of FeNPs at 22.4 mg/L resulted in higher enzymatic antioxidant activities (SOD = 3.5 ± 0.042 U/mg; POD = 2.6 ± 0.026 U/mg; CAT = 2.8 ± 0.034 U/mg and APx = 3.6 ± 0.043 U/ mg), respectively. Furthermore, exposure to a higher dose of FeNPs (22.4 mg/L) exhibited the maximum amount of stevioside (stevioside: 4.6 ± 0.058 mg/g (DW) and rebaudioside A: 4.9 ± 0.068 mg/g DW) as compared to other doses. The current investigation confirms the effectiveness of FeNPs in growth media. It offers a suitable prospect for commercially desirable production of S. rebaudiana biomass with higher sweet glycosides profiles in vitro.

Keywords: cell culture, stevia, iron nanoparticles, antioxidants

Procedia PDF Downloads 96

Authors: Sharmin Ferdewsi Rakhi, A. H. M. Mohsinul Reza, Brynley Davies, Jianzhong Wang, Youhong Tang, Jian Qin

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Mass production of microalgae has become a focus of research owing to their promising aspects for sustainable food, biofunctional compounds, and biofuel feedstock. However, low lipid content with optimum algal biomass is still a challenge that must be resolved for commercial use. This research aims to determine the effects of light spectral shift and reactive oxygen species (ROS) on growth and lipid biosynthesis in a green microalga, Chlamydomonas reinhardtii. Aggregation Induced Emission (AIE)-based photosensitisers, CN-TPAQ-PF6 ([C₃₂H₂₃N₄]+) with high ROS productivity, was introduced into the algal culture media separately for effective conversion of the green-yellow-light to the red spectra. The intense photon energy and high-photon flux density in the photosystems and ROS supplementation induced photosynthesis and lipid biogenesis. In comparison to the control, maximum algal growth (0.15 g/l) was achieved at 2 µM CN-TPAQ-PF6 exposure. A significant increase in total lipid accumulation (146.87 mg/g dry biomass) with high proportion of 10-Heptadecanoic acid (C17:1) linolenic acid (C18:2), α-linolenic acid (C18:3) was observed. The elevated level of cellular NADP/NADPH triggered the Acetyl-Co-A production in lipid biogenesis cascade. Furthermore, MTT analysis suggested that this nanomaterial is highly biocompatible on HaCat cell lines with 100% cell viability. This study reveals that the AIE-based approach can strongly impact algal biofactory development for sustainable food, healthy lipids and eco-friendly biofuel.

Keywords: microalgae, photosensitiser, lipid, biomass, aggregation-induced-emission, reactive oxygen species

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Authors: Ronel Solis, Leonardo Collado

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Migration law in the Republic of Panama has been regulated mainly by the executive branch. This has created a crisis not only institutional but also social because the evolution of these norms has rested greatly from the discretion of the government in office. This has created instability in immigration regulation and more now, with the migration crisis of which Panama is also part. Different migration policies have been established. The most recent is that of the controlled migration flow, in which, for humanitarian reasons, migrants move from the border with Colombia to the border with Costa Rica. Unfortunately, such control is not enough, and in some cases, unprotected migrants have been confined for months, their passports have been withheld, and no recognition of their rights is offered. The Inter-American Court of Human Rights has condemned Panama for the unfair detention of an irregular migrant, who was detained for two years in Panamanian prisons, without having committed a crime and without accessing a just defense. This is the case Vélez Loor vs. the Republic of Panama. Uncontrollable migration has been putting pressure on Panamanian public health services. The recent denunciation of HIV-related NGOs that warns that there are hundreds of foreigners who receive expensive antiretroviral therapy in Panama is serious, and several of them are irregular migrants. On the other hand, there are no border control posts with the Republic of Colombia, because it is a jungle area and migrants are exposed to arms and drug trafficking, and unfortunately, also to prostitution. Government entities such as the border police service have provided humanitarian support to migrants on the border with Colombia, although it is not their administrative function, and various entities discuss who should address this crisis. However, few economic resources are allocated by the government to solve this problem, especially with the recent mass migration of Venezuelans who have fled their country. The establishment of a migratory normative code is necessary to establish uniformity in the recognition and application of migratory rights. In this way, dependence on the changing migration policies of the different Panamanian governments would be eliminated, and the rights of migrants and nationals would be guaranteed.

Keywords: executive branch, irregular migration, migration code, Republic of Panama

Procedia PDF Downloads 123

Authors: Dhananjoy Shaw, Seema Sharma (Kaushik)

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Anthropometry helps in associating the physical properties of an individual with their racial, cultural, and psychological attributes. Numerous research studies have included different skeletal diameters as a variable. However, most of the studies suggest their inclusion describing specific characteristics/traits of the body. However, there seems to be a scarcity of literature related to the effect of any kind of longitudinal physical training on human skeletal diameters. Hence, the present investigation was conducted to study the variability of covariance of selected skeletal diameters of females in a longitudinal physical training programme. The sample for the study was 78 college going students of the University of Delhi, classified equally in three groups, i.e. viz. (a) Progressive load of training or conditioning group coded as PLT; (b) Constant load of training or non-conditioning group coded as CLT; and (c) No-load or control or sedentary group coded as NL. Collectively, mean age of the sample was 19.54±1.79 years. The randomly selected samples were given maximum consideration to maintain their homogeneity. The variables included biacromial diameter, biiliocristal diameter, bitrochantaerion diameter, humeral bicondylar, femoral bicondylar, wrist diameter, ankle diameter, and foot breadth. Multi-group repeated measure design was adopted for the experimentation. Each group was measured four times after completion of each of the three meso-cycles of six-weeks duration. The measurements were taken following the standard landmarks and procedures. Mean, standard deviation, analysis of co-variance and its post-hoc analysis were computed to analyze the data statistically. The study concluded that both the progressive and constant load of physical training bring changes in the selected skeletal diameters of females. It also reflected the increase due to growth also along with training.

Keywords: longitudinal, physical training, skeletal diameters, step progression load

Procedia PDF Downloads 131

Authors: Melissa Dickinson

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In the context of intense global competitiveness and urban transformations, today’s cities are faced with enormous challenges. There is increasing pressure among cities and regions to respond promptly and efficiently to fierce market progressions, to offer a competitive advantage, higher flexibility, and to be pro-active in creating future markets. Consequently, competition among cities and regions within the dynamics of a worldwide spatial economic system is growing fiercer, amplifying the importance of intangible capital in shaping the competitive and dynamic economic performance of organisations and firms. Accordingly, this study addresses how intangible capital influences urban economic development within an urban environment. Despite substantial research on the economic, and strategic determinants of urban economic development this multidimensional phenomenon remains to be one of the greatest challenges for economic geographers. The research provides a unique contribution, exploring intangible capital through the lenses of entrepreneurial capital and social-network capital. Drawing on business surveys and in-depth interviews with key stakeholders in the case of the three UK Core Cities Birmingham, Bristol and Cardiff. This paper critically considers how entrepreneurial capital and social-network capital is a crucial source of competitiveness and urban economic development. This paper deals with questions concerning the complexity of operationalizing ‘network capital’ in different urban settings and the challenges that reside in characterising its effects. The paper will highlight the role of institutions in facilitating urban economic development. Particular emphasis will be placed on exploring the roles formal and informal institutions have in delivering, supporting and nurturing entrepreneurial capital and social-network capital, to facilitate urban economic development. Discussions will then consider how institutions moderate and contribute to the economic development of urban areas, to provide implications in terms of future policy formulation in the context of large and medium sized cities.

Keywords: urban economic development, network capital, entrepreneurialism, institutions

Procedia PDF Downloads 276

Authors: Aminah Salim, Idrees Ahmed Nasir, Abdul Qayyum Rao, Muhammad Ali, Muhammad Sohail Anjum, Ayesha Hameed, Bushra Tabassum, Anwar Khan, Arfan Ali, Mariyam Zameer, Tayyab Husnain

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Risk assessment of transgenic herbicide tolerant sugarcane having CEMB codon optimized cp4EPSPS gene was done in present study. Fifteen days old chicks taken from K&Ns Company were randomly assorted into four groups with eight chicks in each group namely control chicken group fed with commercial diet, non-transgenic group fed with non-experimental sugarcane and transgenic group fed with transgenic sugarcane with minimum and maximum level. Body weights, biochemical analysis for Urea, alkaline phosphatase, alanine transferase, aspartate transferase, creatinine and bilirubin determination and histological examination of chicks fed with four types of feed was taken at fifteen days interval and no significant difference was observed in body weight biochemical and histological studies of all four groups. Protein isolated from the serum sample was analyzed through dipstick and SDS-PAGE, showing the absence of transgene protein in the serum sample of control and experimental groups. Moreover the amplification of cp4EPSPS gene with gene specific primers of DNA isolated from chicks blood and also from commercial diet was done to determine the presence and mobility of any nucleotide fragment of the transgene in/from feed and no amplification was obtained in feed as well as in blood extracted DNA of any group. Also no mRNA expression of cp4EPSPS gene was obtained in any tissue of four groups of chicks. From the results it is clear that there is no deleterious or harmful effect of the CEMB codon optimized transgenic cp4EPSPS sugarcane on the chicks health.

Keywords: chicks, cp4EPSPS, glyphosate, sugarcane

Procedia PDF Downloads 372

Authors: S. Wakim, M. Nemer, B. Zeghondy, B. Ghannam, C. Bouallou

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Designing the optimal heat exchanger is still an essential objective to be achieved. Parametrical optimization involves the evaluation of the heat exchanger dimensions to find those that best satisfy certain objectives. This method contributes to an enhanced design rather than an optimized one. On the contrary, topology optimization finds the optimal structure that satisfies the design objectives. The huge development in metal additive manufacturing allowed topology optimization to find its way into engineering applications especially in the aerospace field to optimize metal structures. Using topology optimization in 3d heat and mass transfer problems requires huge computational time, therefore coupling it with CFD simulations can reduce this it. However, existed CFD models cannot be coupled with topology optimization. The CFD model must allow creating a uniform mesh despite the initial geometry complexity and also to swap the cells from fluid to solid and vice versa. In this paper, a porous media approach compatible with topology optimization criteria is developed. It consists of modeling the fluid region of the heat exchanger as porous media having high porosity and similarly the solid region is modeled as porous media having low porosity. The switching from fluid to solid cells required by topology optimization is simply done by changing each cell porosity using a user defined function. This model is tested on a plate and fin heat exchanger and validated by comparing its results to experimental data and simulations results. Furthermore, this model is used to perform a material reallocation based on local criteria to optimize a plate and fin heat exchanger under a constant heat duty constraint. The optimized fin uses 20% fewer materials than the first while the pressure drop is reduced by about 13%.

Keywords: computational methods, finite element method, heat exchanger, porous media, topology optimization

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Authors: Perdana Rakhmana Putra, Hansen Wijaya, Sri Budiyani, Muhamad Natsir, Alexis badai Samudra

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The Palembang Sub-Basin (PSB) located in southern part of South Sumatera basin (SSB) consist of half-graben complex trending N-S to NW-SE. These geometries are believe as an impact of strike-slip regime developed in Eocene-Oligocene. Generally, most of the wells in this area produced hydrocarbon from late stage of syn-rift sequences called Lower Talang Akar (LTAF) and post-rift sequences called Batu Raja Formation (BRF) and drilled to proved hydrocarbon on structural trap; three-way dip anticline, four-way dip anticline, dissected anticline, and stratigraphy trap; carbonate build-up and stratigraphic pinch out. Only a few wells reached the deeper syn-rift sequences called Lahat Formation (LAF) and Lemat Formation (LEF). The new interpretation of subsurface data was done by the tectonostratigraphy concept and focusing on syn-rift sequence. Base on seismic characteristic on basin centre, it divided into four sequences: pre-rift sequence, rift initiation, maximum rift and late rift. These sequences believed as a new exploration target on PSB mature basin. This paper will demonstrate the paleo depositional setting during Paleogene and exploration play concept of syn-rift sequence in PSB. The main play for this area consists of stratigraphic and structure play, where the stratigraphic play is Eocene-Oligocene sediment consist of LAF sandstone, LEF-Benakat formation, and LAF with pinch-out geometry. The pinch-out, lenses geometry and on-lap features can be seen on the seismic reflector and formed at the time of the syn-rift sequence. The structural play is dominated by a 3 Way Dip play related to reverse fault trap.

Keywords: syn-rift, tectono-stratigraphy, exploration play, basin center play, south sumatera basin

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Authors: Aymen Laadhari

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During the last decade, an increasing number of contributions have been made in the fields of scientific computing and numerical methodologies applied to the study of the hemodynamics in the heart. In contrast, the numerical aspects concerning the interaction of pulsatile blood flow with highly deformable thin leaflets have been much less explored. This coupled problem remains extremely challenging and numerical difficulties include e.g. the resolution of full Fluid-Structure Interaction problem with large deformations of extremely thin leaflets, substantial mesh deformations, high transvalvular pressure discontinuities, contact between leaflets. Although the Lagrangian description of the structural motion and strain measures is naturally used, many numerical complexities can arise when studying large deformations of thin structures. Eulerian approaches represent a promising alternative to readily model large deformations and handle contact issues. We present a fully Eulerian finite element methodology tailored for the simulation of pulsatile blood flow in the aorta and sinus of Valsalva interacting with highly deformable thin leaflets. Our method enables to use a fluid solver on a fixed mesh, whilst being able to easily model the mechanical properties of the valve. We introduce a semi-implicit time integration scheme based on a consistent NewtonRaphson linearization. A variant of the classical Newton method is introduced and guarantees a third-order convergence. High-fidelity computational geometries are built and simulations are performed under physiological conditions. We address in detail the main features of the proposed method, and we report several experiments with the aim of illustrating its accuracy and efficiency.

Keywords: eulerian, level set, newton, valve

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Authors: Neda Nabid

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Friction-based supplemental devices have been extensively used for seismic protection and strengthening of structures, however, the conventional use of these dampers may not necessarily lead to an efficient structural performance. Conventionally designed friction dampers follow a uniform height-wise distribution pattern of slip load values for more practical simplicity. This can lead to localizing structural damage in certain story levels, while the other stories accommodate a negligible amount of relative displacement demand. A practical performance-based optimization methodology is developed to tackle with structural damage localization of RC frame buildings with friction energy dissipation devices under severe earthquakes. The proposed methodology is based on the concept of uniform damage distribution theory. According to this theory, the slip load values of the friction dampers redistribute and shift from stories with lower relative displacement demand to the stories with higher inter-story drifts to narrow down the discrepancy between the structural damage levels in different stories. In this study, the efficacy of the proposed design methodology is evaluated through the seismic performance of five different low to high-rise RC frames equipped with friction wall dampers under six real spectrum-compatible design earthquakes. The results indicate that compared to the conventional design, using the suggested methodology to design friction wall systems can lead to, by average, up to 40% reduction of maximum inter-story drift; and incredibly more uniform height-wise distribution of relative displacement demands under the design earthquakes.

Keywords: friction damper, nonlinear dynamic analysis, RC structures, seismic performance, structural damage

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Authors: Cheryl Teelucksingh

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Toronto is in the midst of an urban development and infrastructure boom. Population growth and concerns about urban sprawl and carbon emissions have led to pressure on the municipal and the provincial governments to re-think urban development. Toronto’s approach to climate change mitigation and adaptation has positioning of the emerging green economy as part of the solution. However, the emerging green economy many not benefit all Torontonians in terms of jobs, improved infrastructure, and enhanced quality of life. Community benefits agreements (CBAs) are comprehensive, negotiated commitments, in which founders and builders of major infrastructure projects formally agree to work with community interest groups based in the community where the development is taking place, toward mutually beneficial environmental and labor market outcomes. When community groups are equitably represented in the process, they stand not only to benefit from the jobs created from the project itself, but also from the longer-term community benefits related to the quality of the completed work, including advocating for communities’ environmental needs. It is believed that green employment initiatives in Toronto should give greater consideration to best practices learned from community benefits agreements. Drawing on the findings of a funded qualitative study in Toronto (Canada), “The Green Gap: Toward Inclusivity in Toronto’s Green Economy” (2013-2016), this paper examines the emergent CBA in Toronto in relation to the development of a light rail transit project. Theoretical and empirical consideration will be given to the research gaps around CBAs, the role of various stakeholders, and discuss the potential for CBAs to gain traction in the Toronto’s urban development context. The narratives of various stakeholders across Toronto’s green economy will be interwoven with a discussion of the CBA model in Toronto and other jurisdictions.

Keywords: green economy in Toronto, equity, community benefits agreements, environmental justice, community sustainability

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Authors: Md. Rezaul Karim, Md. Ashikur Rahman, Dewan Mahmud Mim

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Scarcity of potable water as the result of rapid climate change and saltwater intrusion in groundwater has been a major problem in the coastal regions over the world. In equinoctial countries like Bangladesh, where sunlight is available for more than 10 hours a day, Solar Distillation provides a promising sustainable way for safe drinking water supply in coastal poor households with negligible major cost and difficulty of construction and maintenance. In this paper, two passive type solar stills- a Conventional Single Slope Solar still (CSS) and a Pyramid Solar Sill (PSS) is used and relationship is established between distill water output corresponding to four different factors- temperature, solar intensity, relative humidity and wind speed for Gazipur, Bangladesh. Comparison is analyzed between the two different still outputs for nine months period (January- September) and efficiency is calculated. Later a thermal mathematical model is developed and the distilled water output for Khulna, Bangladesh is computed. Again, difference between the output of the two cities- Gazipur and Khulna is demonstrated and finally an economic analysis is prepared. The distillation output has a positive correlation with temperature and solar intensity, inverse relation with relative humidity and wind speed has nugatory consequence. The maximum output of Conventional Solar Still is obtained 3.8 L/m2/day and Pyramid still is 4.3 L/m2/day for Gazipur and almost 15% more efficiency is found for Pyramid still. Productivity in Khulna is found almost 20% more than Gazipur. Based on economic analysis, taking 10 BDT, per liter, the net profit, benefit cost ratio, payback period all indicates that both stills are feasible but pyramid still is more feasible than Conventional Still. Finally, for a 3-4 member family, area of 4 m2 is suggested for Conventional Still and 3m2 for Pyramid Solar Still.

Keywords: solar distillation, household water supply, saline zones, Bangladesh

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Authors: Sanjeev Singh

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Background: Obstructed total anomalous pulmonary venous connection (OTAPVC) typically presents with severe cardiovascular decompensation and requires urgent surgical management. Pulmonary arterial hypertension (PAH) is a major risk factor affecting mortality. Perioperative management focuses on providing inotropic support and managing potential pulmonary hypertensive episodes. The aim of this study was to determine the outcome of patients with high pulmonary arterial pressure (PAP) with milrinone alone and a combination of milrinone and inhaled nitric oxide (INO). Material and Methods: After the approval of the ethical committee, this single-center prospective randomized and observational study was conducted over a period of two years among eighty-six patients with obstructed TAPVC repair with severe PAH. Group-I patients received milrinone, and Group-II patients received both milrinone (after aortic cross-clamp removal) and INO during the post-operative period at the cardiac care unit (CCU). Clinical outcomes such as ventilation time, length of stay (LOS) in the CCU, LOS in the hospital, complications, and hospital mortality were compared between the two groups. Result: The average ventilation time, LOS in CCU, and LOS in hospital for group I were 96.82 ± 19.46 hours, 10.91 ± 7.53 days, and 14.46 ± 7.58 days, respectively, and for group II, it was 85.14 ± 15.79 hours, 7.28 ± 3.68 days, and 10.21 ± 3.14 days, respectively, which was statistically significantly lower for group II. Reintubation, RV dysfunction, and hospital mortality were 16.3%, 37.2%, and 6.9% in group I, and 4.8%, 14.6%, and 2.4% in group II, respectively. The P value for each variable was significant < 0.05 (except mortality). Conclusion: Preoperative obstruction is a risk factor for postoperative obstruction, as 235 patients with obstructed TAPVC had severe PAH (39.98%) in this study. Management of severe PAH with a combination of milrinone and INO had a better outcome than milrinone alone.

Keywords: inhaled nitric oxide, milrinone, pulmonary artery hypertension, total anomalous pulmonary venous connection

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Authors: Maria Rodriguez-Gazquez, Sara Chaparro-Hernandez, Jose Rafael Gonzalez-Lopez

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Introduction: Nurses are models in healthy behaviors for their patients. This is why it is important for these professionals to not only have a good knowledge of healthy behaviors but also practice. Today’s nursing students will be tomorrow’s professionals and to fulfill their role in caring they not only need knowledge, they also must maintain behaviors which enable them to improve and protect both the health of others and their own. This is why the university is a unique environment of opportunities to foster the maximum potential of health. To care for others we first have to take care of ourselves. It is important for these behaviors in Nursing students to be evaluated during the years of their university education in order to design timely interventions which improve the health behaviors of the future professionals. Aim: The objective of this study was to evaluate the lifestyles of first year nursing students of two Universities. Methodology: Cross-sectional study. In 2014, 140 first year Nursing students of two Universities Seville –US- (Spain -Europe, n=37) and Antioquia –UA- (Colombia -South America, n=93) self-reported the FANTASTIC Lifestyle checklist. Results: Findings reveal that (I) UA students doubled the percentage of dangerous or bad lifestyles with respect to the US students, (II) the lifestyles are not appropriate in 1 of 3 of nursing students in both Universities, (II) there are statistically significant differences for family support items (higher in US), positive thinkers (higher in UA), the use of safety belts and alcohol consumption before driving (higher in US). Discussion: The nursing students are mostly young people who are at a stage in which some of the most important behaviors for adult life can still be molded. It is necessary to develop educational interventions in their Nursing curricula to strengthen healthy behaviours during training. Nursing Schools not only have the duty to train professionals, but to also be agents that foster the health, welfare and quality of those who study and work there. It must encourage knowledge and skills oriented to healthy lifestyles.

Keywords: cross-sectional studies, life style, nursing students, questionnaires

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Authors: M. Rahou, A. J. Andrews, G. Rosengarten

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One of the main challenges in high-temperature solar thermal applications transfer concentrated solar radiation to the load with minimum energy loss and maximum overall efficiency. The use of a solar concentrator in conjunction with bundled optical fibres has potential advantages in terms of transmission energy efficiency, technical feasibility and cost-effectiveness compared to a conventional heat transfer system employing heat exchangers and a heat transfer fluid. In this paper, a theoretical and computer simulation method is described to estimate the net solar radiation transmission from a solar concentrator into and through optical fibres to a thermal application at the end of the fibres over distances of up to 100 m. A key input to the simulation is the angular distribution of radiation intensity at each point across the aperture plane of the optical fibre. This distribution depends on the optical properties of the solar concentrator, in this case, a parabolic mirror with a small secondary mirror with a common focal point and a point-focus Fresnel lens to give a collimated beam that pass into the optical fibre bundle. Since solar radiation comprises a broad band of wavelengths with very limited spatial coherence over the full range of spectrum only ray tracing models absorption within the fibre and reflections at the interface between core and cladding is employed, assuming no interference between rays. The intensity of the radiation across the exit plane of the fibre is found by integrating across all directions and wavelengths. Results of applying the simulation model to a parabolic concentrator and point-focus Fresnel lens with typical optical fibre bundle will be reported, to show how the energy transmission varies with the length of fibre.

Keywords: concentrated radiation, fibre bundle, parabolic dish, fresnel lens, transmission

Procedia PDF Downloads 564

Authors: Shang-Yu Chiang, Yu-Shan Tsai, Shih-Hsien Sung, Chung-Ming Lo

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Mitral regurgitation (MR) is a heart disorder which the mitral valve does not close properly when the heart pumps out blood. MR is the most common form of valvular heart disease in the adult population. The diagnostic echocardiographic finding of MR is straightforward due to the well-known clinical evidence. In the determination of MR severity, quantification of sonographic findings would be useful for clinical decision making. Clinically, the vena contracta is a standard for MR evaluation. Vena contracta is the point in a blood stream where the diameter of the stream is the least, and the velocity is the maximum. The quantification of vena contracta, i.e. the vena contracta width (VCW) at mitral valve, can be a numeric measurement for severity assessment. However, manually delineating the VCW may not accurate enough. The result highly depends on the operator experience. Therefore, this study proposed an automatic method to quantify VCW to evaluate MR severity. Based on color Doppler ultrasound, VCW can be observed from the blood flows to the probe as the appearance of red or yellow area. The corresponding brightness represents the value of the flow rate. In the experiment, colors were firstly transformed into HSV (hue, saturation and value) to be closely align with the way human vision perceives red and yellow. Using ellipse to fit the high flow rate area in left atrium, the angle between the mitral valve and the ultrasound probe was calculated to get the vertical shortest diameter as the VCW. Taking the manual measurement as the standard, the method achieved only 0.02 (0.38 vs. 0.36) to 0.03 (0.42 vs. 0.45) cm differences. The result showed that the proposed automatic VCW extraction can be efficient and accurate for clinical use. The process also has the potential to reduce intra- or inter-observer variability at measuring subtle distances.

Keywords: mitral regurgitation, vena contracta, color doppler, image processing

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Authors: Thavananthan Sivananthawerl

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Coconut palm is existing for more than 2000 years in Sri Lanka. However, cultivation on a large scale (plantation) began only in the 19th century. Due to different light perceptions during the growth stages of palm, there is a huge potential to grow crops in-between rows of coconut plants which are grown with wider, fixed spacing. Intercropping under coconut will have multiple benefits such as increasing soil fertility, increasing sunlight utilization, increasing total crop productivity, increasing income & profit, maximum use of resources, reducing the risk, and increasing food security. Growing potential annual, agricultural intercrops could be classified as ‘agri-silvicultural’ system. This is the best agri-silvicultural system that can be named under any perennial crop system in Sri Lanka. In the late 1970’s cassava, pepper and cacao are the major intercrops under the coconut plantations. At the early ages of the palm (<5 years) light-loving crops such as pineapple, passion, papaya, and cassava are recommended and preferred by the cultivators. In between 5-20 years of age, the availability of light is very low, and therefore shade tolerant/loving crops (pasture, yam, ginger) could be used as the intercrops. However, after 20 years of age (>20 years) canopy is getting small, and the light availability on the ground increases. So, light demanding crops such as pepper, banana, pineapple, betel, cassava, and seasonal crops could be grown successfully. Even though this is a sustainable system in several aspects, there are potential challenges ahead to the system. The major ones are land fragmentation and infrastructure development. The other factors are drought, lack of financial support, price instability of the intercrops, availability of improved planting materials, and development of dwarf varieties which reduces the light.

Keywords: coconut cultivation, agri-silviculture, intercrop, sunlight, annuals, sustainability

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Authors: Lidija Trandafilovic, Kirsten Leistner, Marie Stenfeldt, Louise Olsson

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Ammonia Selective Catalytic Reduction (NH3 SCR), is one of the most efficient post combustion abatement technologies for removing NOx from diesel engines. In order to remove soot, diesel particulate filters (DPF) are used. Recently, SCR coated filters have been introduced, which captures soot and simultaneously is active for ammonia SCR. There are large advantages with using SCR coated filters, such as decreased volume and also better light off characteristics, since both the SCR function as well as filter function is close to the engine. The objective of this work was to examine the effect of soot, produced using an engine bench, on Cu/SSZ-13 catalysts. The impact of soot on Cu/SSZ-13 in standard SCR, NH3 oxidation, NH3 temperature programmed desorption (TPD), as well as soot oxidation (with and without water) was examined using flow reactor measurements. In all experiments, prior to the soot loading, the fresh activity of Cu/SSZ-13 was recorded with stepwise increasing the temperature from 100°C till 600°C. Thereafter, the sample was loaded with soot and the experiment was repeated in the temperature range from 100°C till 700°C. The amount of CO and CO2 produced in each experiment is used to calculate the soot oxidized at each steady state temperature. The soot oxidized during the heating to next temperature step is included, e.g. the CO+CO2 produced when increasing the temperature to 600°C is added to the 600°C step. The influence of the two factors seem to be of the most importance to soot oxidation: ammonia and water. The influence of water on soot oxidation shift the maximum of CO2 and CO production towards lower temperatures, thus water increases the soot oxidation. Moreover, when adding ammonia to the system it is clear that the soot oxidation is lowered in the presence of ammonia, resulting in larger integrated COx at 500°C for O2+H2O, while opposite results at 600 °C was received where more was oxidised for O2+H2O+NH3 case. To conclude the presence of ammonia reduces the soot oxidation, which is in line with the ammonia TPD results where we found ammonia storage on the soot. Interestingly, during ammonia SCR conditions the activity for soot oxidation is regained at 500°C. At this high temperature the SCR zone is very short, thus the majority of the catalyst is not exposed to ammonia and therefore the inhibition effect of ammonia is not observed.

Keywords: NH3-SCR, Cu/SSZ-13, soot, zeolite

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Authors: Nayak Amar, Turner Naomi, Gobina Edward

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The Scottish Higher Education Institutes must report their scope 1 & 2 emissions, whereas reporting scope 3 is optional. Scope 3 is indirect emissions which embodies a significant component of total carbon footprint and therefore it is important to record, measure and report it accurately. Robert Gordon University (RGU) reported only business travel, grid transmission and distribution, water supply and transport, and recycling scope 3 emissions. This study estimates the RGUs total scope 3 emissions by comparing it with a similar HEI in scale. The scope 3 emission reporting of sixteen Scottish HEI was studied. Glasgow Caledonian University was identified as the nearest neighbour by comparing its students' full time equivalent, staff full time equivalent, research-teaching split, budget, and foundation year. Apart from the peer, data was also collected from the Higher Education Statistics Agency database. RGU reported emissions from business travel, grid transmission and distribution, water supply, and transport and recycling. This study estimated RGUs scope 3 emissions from procurement, student-staff commute, and international student trip. The result showed that RGU covered only 11% of the scope 3 emissions. The major contributor to scope 3 emissions were procurement (48%), student commute (21%), international student trip (16%), and staff commute (4%). The estimated scope 3 emission was more than 14 times the reported emissions. This study has shown the relative importance of each scope 3 emissions source, which gives a guideline for the HEIs, on where to focus their attention to capture maximum scope 3 emissions. Moreover, it has demonstrated that it is possible to estimate the scope 3 emissions with limited data.

Keywords: HEI, university, emission calculations, scope 3 emissions, emissions reporting

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Authors: Marji Umil, Miane Karyle Urolaza, Ian Winston Dale Uy, John Charle Magne Valdez, Karen Elizabeth Valdez, Ervin Charles Valencia, Cheryleen Tan-Chua

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Objective: Distraction techniques can be successful in reducing the anxiety of children during medical procedures. Dental procedures, in particular, are associated with dental anxiety which has been identified as a significant and common problem in children, however, only limited studies were conducted to address such problem. Thus, this study determined the effectiveness of computer video games on the levels of anxiety of children between 5-12 years old scheduled for tooth extraction. Methods: A pre-test post-test quasi-experimental study was conducted involving 30 randomly-assigned subjects, 15 in the experimental and 15 in the control. Subjects in the experimental group played computer video games for a maximum of 15 minutes, however, no intervention was done on the control. The modified Yale Pre-operative Anxiety Scale (m-YPAS) with a Cronbach’s alpha of 0.9 was used to assess anxiety at two different points: upon arrival in the clinic (pre-test anxiety) and 15 minutes after the first measurement (post-test anxiety). Paired t-test and ANCOVA were used to analyze the gathered data. Results: Results showed that there is a significant difference between the pre-test and post-test anxiety scores of the control group (p=0.0002) which indicates an increased anxiety. A significant difference was also noted between the pre-test and post-test anxiety scores of the experimental group (p=0.0002) which indicates decreased anxiety. Comparatively, the experimental group showed lower anxiety score (p=<0.0001) than the control. Conclusion: The use of computer video games is effective in reducing the pre-operative anxiety among children and can be an alternative non-pharmacological management in giving pre-operative care.

Keywords: play therapy, preoperative anxiety, tooth extraction, video games

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Authors: Khalid Iqbal

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This work presents a comparison of an anthropomorphic PRESAGE® dosimeter and radiochromic film measurements with a commercial treatment planning system to determine the feasibility of PRESAGE® for 3D dosimetry in breast IMRT. An anthropomorphic PRESAGE® phantom was created in the shape of a breast phantom. A five-field IMRT plan was generated with a commercially available treatment planning system and delivered to the PRESAGE® phantom. The anthropomorphic PRESAGE® was scanned with the Duke midsized optical CT scanner (DMOS-RPC) and the OD distribution was converted to dose. Comparisons were performed between the dose distribution calculated with the Pinnacle3 treatment planning system, PRESAGE®, and EBT2 film measurements. DVHs, gamma maps, and line profiles were used to evaluate the agreement. Gamma map comparisons showed that Pinnacle3 agreed with PRESAGE® as greater than 95% of comparison points for the PTV passed a ± 3%/± 3 mm criterion when the outer 8 mm of phantom data were discluded. Edge artifacts were observed in the optical CT reconstruction, from the surface to approximately 8 mm depth. These artifacts resulted in dose differences between Pinnacle3 and PRESAGE® of up to 5% between the surface and a depth of 8 mm and decreased with increasing depth in the phantom. Line profile comparisons between all three independent measurements yielded a maximum difference of 2% within the central 80% of the field width. For the breast IMRT plan studied, the Pinnacle3 calculations agreed with PRESAGE® measurements to within the ±3%/± 3 mm gamma criterion. This work demonstrates the feasibility of the PRESAGE® to be fashioned into anthropomorphic shape, and establishes the accuracy of Pinnacle3 for breast IMRT. Furthermore, these data have established the groundwork for future investigations into 3D dosimetry with more complex anthropomorphic phantoms.

Keywords: 3D dosimetry, PRESAGE®, IMRT, QA, EBT2 GAFCHROMIC film

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Authors: Abdullah Alnutayfat, Alexander Sutin

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One of the most important types of renewable energy resources is wind energy which can be produced by wind turbines. The blades of the wind turbine are exposed to the pressure of the harsh environment, which causes a significant issue for the wind power industry in terms of the maintenance cost and failure of blades. One of the reliable methods for blade inspection is the vibroacoustic structural health monitoring (SHM) method which examines information obtained from the structural vibrations of the blade. However, all vibroacoustic SHM techniques are based on comparing the structural vibration of intact and damaged structures, which places a practical limit on their use. Methods for nonlinear vibroacoustic SHM are more sensitive to damage and cracking and do not need to be compared to data from the intact structure. This paper presents the Vibro-Acoustic Modulation (VAM) method based on the modulation of high-frequency (probe wave) by low-frequency loads (pump wave) produced by the blade rotation. The blade rotation alternates bending stress due to gravity, leading to crack size variations and variations in the blade resonance frequency. This method can be used with the classical SHM vibration method in which the blade is excited by piezoceramic actuator patches bonded to the blade and receives the vibration response from another piezoceramic sensor. The VAM modification of this method analyzes the spectra of the detected signal and their sideband components. We suggest the VAM model as the simple mechanical oscillator, where the parameters of the oscillator (resonance frequency and damping) are varied due to low-frequency blade rotation. This model uses the blade vibration parameters and crack influence on the blade resonance properties from previous research papers to predict the modulation index (MI).

Keywords: wind turbine blades, damaged detection, vibro-acoustic structural health monitoring, vibro-acoustic modulation

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Authors: Jacob Hatherell, Jason Matthews, Arnaud Marmier

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Anvil Staking is a cold-forming process that is used in the assembly of plain spherical bearings into a rod-end housing. This process ensures that the bearing outer lip conforms to the chamfer in the matching rod end to produce a lightweight mechanical joint with sufficient strength to meet the pushout load requirement of the assembly. Finite Element (FE) analysis is being used extensively to predict the behaviour of metal flow in cold forming processes to support industrial manufacturing and product development. On-going research aims to validate FE models across a wide range of bearing and rod-end geometries by systematically isolating and understanding the uncertainties caused by variations in, material properties, load-dependent friction coefficients and strain rate sensitivity. The improved confidence in these models aims to eliminate the costly and time-consuming process of experimental trials in the introduction of new bearing designs. Previous literature has shown that friction coefficients do not remain constant during cold forming operations, however, the understanding of this phenomenon varies significantly and is rarely implemented in FE models. In this paper, a new approach to evaluate the normal contact pressure versus friction coefficient relationship is outlined using friction calibration charts generated via iterative FE models and ring compression tests. When compared to previous research, this new approach greatly improves the prediction of forming geometry and the forming load during the staking operation. This paper also aims to standardise the FE approach to modelling ring compression test and determining the friction calibration charts.

Keywords: anvil staking, finite element analysis, friction coefficient, spherical plain bearing, ring compression tests

Procedia PDF Downloads 205