Search results for: solar blind photodetector
365 Evaluation of the Irritation Potential of Three Topical Formulations of Minoxidil 2% Using Patch Test
Authors: Sule Pallavi, Shah Priyank, Thavkar Amit, Rohira Poonam, Mehta Suyog
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Introduction: Minoxidil has been used topically for a long time to assist hair growth in the management of male androgenetic alopecia. The aim of this study was a comparative assessment of the irritation potential of three commercial formulations of minoxidil 2% topical solution in a human patch test. Methodology: The study was a non-randomized, double-blind, controlled, single-center study of 56 healthy adult Indian subjects. A 24-hour occlusive patch test was conducted with three formulations of minoxidil 2% topical solution. Products tested were aqueous-based minoxidil 2% (AnasureTM 2%, Sun Pharma, India – Brand A), alcohol-based minoxidil 2% (Brand B) and aqueous-based minoxidil 2% (Brand C). Isotonic saline 0.9% and 1% w/w sodium lauryl sulphate as a negative and positive control, respectively, were included. Patches were applied on the back, followed by removal after 24 hours. The Draize scale (0-4 points scale for erythema/dryness/wrinkles and for oedema) was used to evaluate and clinically score the skin reaction under constant artificial daylight 24 hours after the removal of the patches. The patch test was based on the principles outlined by Bureau of Indian Standards (BIS) (IS 4011:2018; Methods of Test for safety evaluation of Cosmetics-3rd revision). A mean combined score up to 2.0/8.0 indicates that a product is “non-irritant,” and a score between 2.0/8.0 and 4.0/8.0 indicates “mildly irritant” and a score above 4.0/8.0 indicates “irritant”. In case of any skin reaction that was observed, a follow-up was planned after one week to confirm recovery. Results: The 56 subjects who participated in the study had a mean age of 28.7 years (28 males and 28 females). The combined mean score ± standard deviation was: 0.09 ± 0.29 (Brand A), 0.29± 0.53 (Brand B), 0.30 ± 0.46 (Brand C), 3.25 ± 0.77 (positive control) and 0.02 ± 0.13 (negative control). This mean score of Brand A (Sun Pharma) was significantly lower than that of Brand B (p=0.016) and that of Brand C (p=0.004). The mean erythema score ± standard deviation was: 0.09 ± 0.29 (Brand A), 0.27 ± 0.49 (Brand B), 0.30 ± 0.46 (Brand C), 2.5 ± 0.66 (positive control) and 0.02 ± 0.13 (negative control). The mean erythema score of Brand A (Sun Pharma) was significantly lower than that of Brand B (p=0.019) and that of Brand C (p=0.004). Reactions that were observed 24 hours after patch removal subsided in a week’s time. Conclusion: Based on the human patch test as per the BIS, IS 4011:2018, all the three topical formulations of minoxidil 2% were found to be non-irritant. Brand A of 2% minoxidil (Sun Pharma) was found to be the least irritant than Brand B and Brand C based on the combined mean score and mean erythema score.Keywords: erythema, irritation, minoxidil, patch test
Procedia PDF Downloads 82364 Comprehensive Regional Drought Assessment Index
Authors: A. Zeynolabedin, M. A. Olyaei, B. Ghiasi
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Drought is an inevitable part of the earth’s climate. It occurs regularly with no clear warning and without recognizing borders. In addition, its impact is cumulative and not immediately discernible. Iran is located in a semi-arid region where droughts occur periodically as natural hazard. Standardized Precipitation Index (SPI), Surface Water Supply Index (SWSI), and Palmer Drought Severity Index (PDSI) are three well-known indices which describe drought severity; each has its own advantages and disadvantages and can be used for specific types of drought. These indices take into account some factors such as precipitation, reservoir storage and discharge, temperature, and potential evapotranspiration in determining drought severity. In this paper, first all three indices are calculated in Aharchay river watershed located in northwestern part of Iran in East Azarbaijan province. Next, based on two other important parameters which are groundwater level and solar radiation, two new indices are defined. Finally, considering all five aforementioned indices, a combined drought index (CDI) is presented and calculated for the region. This combined index is based on all the meteorological, hydrological, and agricultural features of the region. The results show that the most severe drought condition in Aharchay watershed happened in Jun, 2004. The result of this study can be used for monitoring drought and prepare for the drought mitigation planning.Keywords: drought, GIS, intensity index, regional assessment, variation maps
Procedia PDF Downloads 249363 Internet of Things in Higher Education: Implications for Students with Disabilities
Authors: Scott Hollier, Ruchi Permvattana
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The purpose of this abstract is to share the findings of a recently completed disability-related Internet of Things (IoT) project undertaken at Curtin University in Australia. The project focused on identifying how IoT could support people with disabilities with their educational outcomes. To achieve this, the research consisted of an analysis of current literature and interviews conducted with students with vision, hearing, mobility and print disabilities. While the research acknowledged the ability to collect data with IoT is now a fairly common occurrence, its benefits and applicability still need to be grounded back into real-world applications. Furthermore, it is important to consider if there are sections of our society that may benefit from these developments and if those benefits are being fully realised in a rush by large companies to achieve IoT dominance for their particular product or digital ecosystem. In this context, it is important to consider a group which, to our knowledge, has had little specific mainstream focus in the IoT area –people with disabilities. For people with disabilities, the ability for every device to interact with us and with each other has the potential to yield significant benefits. In terms of engagement, the arrival of smart appliances is already offering benefits such as the ability for a person in a wheelchair to give verbal commands to an IoT-enabled washing machine if the buttons are out of reach, or for a blind person to receive a notification on a smartphone when dinner has finished cooking in an IoT-enabled microwave. With clear benefits of IoT being identified for people with disabilities, it is important to also identify what implications there are for education. With higher education being a critical pathway for many people with disabilities in finding employment, the question as to whether such technologies can support the educational outcomes of people with disabilities was what ultimately led to this research project. This research will discuss several significant findings that have emerged from the research in relation to how consumer-based IoT can be used in the classroom to support the learning needs of students with disabilities, how industrial-based IoT sensors and actuators can be used to monitor and improve the real-time learning outcomes for the delivery of lectures and student engagement, and a proposed method for students to gain more control over their learning environment. The findings shared in this presentation are likely to have significant implications for the use of IoT in the classroom through the implementation of affordable and accessible IoT solutions and will provide guidance as to how policies can be developed as the implications of both benefits and risks continue to be considered by educators.Keywords: disability, higher education, internet of things, students
Procedia PDF Downloads 119362 Induced Thermo-Osmotic Convection for Heat and Mass Transfer
Authors: Francisco J. Arias
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Consideration is given to a mechanism of heat and mass transport in solutions similar than that of natural convection but with one important difference. Here the mechanism is not promoted by density differences in the fluid occurring due to temperature gradients (coefficient of thermal expansion) but rather by solubility differences due to the thermal dependence of the solubility (coefficient of thermal solubility). Utilizing a simplified physical model, it is shown that by the proper choice of the concentration of a given solution, convection might be induced by the alternating precipitation of the solute -when the solution becomes supersaturated, and its posterior recombination when changes in temperature occurs. The spontaneous change in the Gibbs free energy during the mixing is the driven force for the mechanism. The maximum extractable energy from this new type of thermal convection was derived. Experimental data from a closed-loop circuit was obtained demonstrating the feasibility for continuous separation and recombination of the solution. This type of heat and mass transport -which doesn’t depend on gravity, might potentially be interesting for heat and mass transport downwards (as in solar-roof collectors to inside homes), horizontal (e.g., microelectronic applications), and in microgravity (space technology). Also, because the coefficient of thermal solubility could be positive or negative, the investigated thermo-osmosis convection can be used either for heating or cooling.Keywords: natural convection, thermal gradient, solubility, osmotic pressure
Procedia PDF Downloads 294361 Comparative Study of IC and Perturb and Observe Method of MPPT Algorithm for Grid Connected PV Module
Authors: Arvind Kumar, Manoj Kumar, Dattatraya H. Nagaraj, Amanpreet Singh, Jayanthi Prattapati
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The purpose of this paper is to study and compare two maximum power point tracking (MPPT) algorithms in a photovoltaic simulation system and also show a simulation study of maximum power point tracking (MPPT) for photovoltaic systems using perturb and observe algorithm and Incremental conductance algorithm. Maximum power point tracking (MPPT) plays an important role in photovoltaic systems because it maximize the power output from a PV system for a given set of conditions, and therefore maximize the array efficiency and minimize the overall system cost. Since the maximum power point (MPP) varies, based on the irradiation and cell temperature, appropriate algorithms must be utilized to track the (MPP) and maintain the operation of the system in it. MATLAB/Simulink is used to establish a model of photovoltaic system with (MPPT) function. This system is developed by combining the models established of solar PV module and DC-DC Boost converter. The system is simulated under different climate conditions. Simulation results show that the photovoltaic simulation system can track the maximum power point accurately.Keywords: incremental conductance algorithm, perturb and observe algorithm, photovoltaic system, simulation results
Procedia PDF Downloads 556360 Development of Transparent Nano-Structured Super-Hydrophobic Coating on Glass and Evaluation of Anti-Dust Properties
Authors: Abhilasha Mishra, Neha Bhatt
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Super-hydrophobicity is an effect in which a surface roughness and chemical composition are combined to produce unusual water and dust repellent surface. The super-hydrophobic surface is widely used in many applications such as windshields of the automobile, aircraft, lens, solar cells, roofing, boat hull, paints, etc. Four coating solutions were prepared by varying compositions of 1,1,1,3,3,3 hexametyldisilazane (HDMS) and tetraethylorthosilicate (TEOS) sol. These solutions were coated on glass slides by a spin coating method and etched at a high temperature ranging 250 -350 oC. All the coatings were studied for its different properties like water repellent, anti-dust, and transparency and contact angle measurements. Stability of coatings was also studied with respect to temperature, external environment, and pH. It was found that all coatings impart a significant super-hydrophobicity on a glass surface with contact angle ranging from 156o to 162o and have good stability in the external environment. The results of the different coatings were observed and compared with each other. On increasing layers of coatings the super-hydrophobicity and anti-dust properties increases but after 3 coatings the transparency of coating starts decreasing.Keywords: super-hydrophobic, contact angle, coating, anti-dust
Procedia PDF Downloads 259359 Visibility Measurements Using a Novel Open-Path Optical Extinction Analyzer
Authors: Nabil Saad, David Morgan, Manish Gupta
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Visibility has become a key component of air quality and is regulated in many areas by environmental laws such as the EPA Clean Air Act and Regional Haze Rule. Typically, visibility is calculated by estimating the optical absorption and scattering of both gases and aerosols. A major component of the aerosols’ climatic effect is due to their scattering and absorption of solar radiation, which are governed by their optical and physical properties. However, the accurate assessment of this effect on global warming, climate change, and air quality is made difficult due to uncertainties in the calculation of single scattering albedo (SSA). Experimental complications arise in the determination of the single scattering albedo of an aerosol particle since it requires the simultaneous measurement of both scattering and extinction. In fact, aerosol optical absorption, in particular, is a difficult measurement to perform, and it’s often associated with large uncertainties when using filter methods or difference methods. In this presentation, we demonstrate the use of a new open-path Optical Extinction Analyzer (OEA) in conjunction with a nephelometer and two particle sizers, emphasizing the benefits that co-employment of the OEA offers to derive the complex refractive index of aerosols and their single scattering albedo parameter. Various use cases, data reproducibility, and instrument calibration will also be presented to highlight the value proposition of this novel Open-Path OEA.Keywords: aerosols, extinction, visibility, albedo
Procedia PDF Downloads 91358 Strategies to Synthesize Ambient Stable Ultrathin Ag Film Supported on Oxide Substrate
Authors: Allamula Ashok, Peela Lasya, Daljin Jacob, P. Muhammed Razi, Satyesh Kumar Yadav
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We report zinc (Zn) as a seed layer material and a need for a specific disposition sequence to grow ultrathin silver (Ag) films on quartz (SiO₂). Ag films of thickness 4, 6, 8 and 10 nm were deposited by DC magnetron sputtering without and with Zn seed layer thickness of 1, 2 and 4 nm. The effect of Zn seed layer thickness and its annealing on the surface morphology, sheet resistance, and stability of ultrathin Ag films is investigated. We show that by increasing Zn seed layer thickness from 1 to 2 nm, there is a 5-order reduction in sheet resistance of 6 nm Ag films. We find that annealing of the seed layer is crucial to achieving stability of ultrathin Ag films. 6 nm Ag film with 2 nm Zn is unstable to 100 oC annealing, while the 6 nm Ag film with annealed 2 nm Zn seed layer is stable. 2 nm Zn seeded 8 nm Ag film maintained a constant sheet resistance of 7 Ω/□ for all 6 months of exposure to ambient conditions. Among the ultrathin film grown, 8nm Ag film with 2nm Zn seed layer had the best figure of merit with sheet resistance of 7 Ω/□, mean absolute surface roughness (Ra) ~1 nm, and optical transparency of 61 %. Such stable exposed ultrathin Ag films can find applications as catalysts, sensors, and transparent and conductive electrodes for solar cells, LEDs and plasmonic devices.Keywords: ultrathin Ag films, magnetron sputtering, thermal stability, seed layer, exposed silver, zinc.
Procedia PDF Downloads 39357 The Effect of Yb3+ Concentration on Spectroscopic properties of Strontium Cerate Doped with Tm3+ and Yb3+
Authors: Yeon Woo Seo, Haeyoung Choi, Jung Hyun Jeong
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Recently, the UC phosphors have attracted much attention owing to their wide applicability in areas such as biological fluorescence labeling, three-dimensional color displays, temperature sensor, solar cells, white light emitting diodes (WLEDs), fiber optic communication, anti-counterfeiting and other areas. The UC efficiency is mainly dependent on the host lattice and the interaction between the host lattice and doped ions. Up to date, various host matrices, such as oxides, fluorides, vanadates and phosphates, have been investigated as efficient UC luminescent hosts. Recently, oxide materials with low phonon energy have been investigated as the host matrices of UC materials due to their high chemical durability and physical stability. A series of Sr2CeO4: Tm3+/Yb3+ phosphors with different concentrations of Yb3+ ions have been successfully prepared using the high-energy ball milling method. In this study, we reported the UC luminescent properties of Tm3+/Yb3+ ions co-doped Sr2CeO4 phosphors under an excitation wavelength of 975 nm. Furthermore, the structural and morphological characteristics, as well as the UC luminescence mechanism were investigated in detail. The X-ray diffraction patterns confirmed their orthorhombic structure. Under 975 nm excitation, the emission peaks were observed at 478 nm (blue) and 652 nm (red), corresponding to the 1G4 → 3H6 and 1G4 → 3F4 transitions of Tm3+, respectively. The optimized doping concentration of Yb3+ ion was 10 mol%.Keywords: Strontium Cerate, up-conversion, luminescence, Tm3+, Yb3+
Procedia PDF Downloads 262356 A Review of Energy in the Democratic Republic of Congo
Authors: Kanzumba Kusakana
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The Democratic Republic of Congo (DRC) is currently experiencing a general energy crisis due to lack of proper investment and management in the energy sector. 93, 6% of the country is highly dependent on wood fuels as main source of energy having severe impacts such as deforestation and general degradation of the environment. On the other hand, the major share of the electricity produced mainly from ill-conditioned hydro and thermal power stations is principally used to supply the industrial sector as well as very few urban areas. Nevertheless, DRC possesses huge potential in renewable resources such as hydropower, biomass, methane gas, solar geothermal and moderate wind potential that can be used for energy generation. Recently the country has initiated projects to build decentralized micro hydropower station to supply remotes and isolated areas; to rehabilitate its existent main hydropower plants and transmission lines as well as to extend its current generation capacity by building new hydropower stations able to respond to a major part of the African continent energy needs. This paper presents a comprehensive review of current energy resources as well as of the electricity situation in DRC. Recent energy projects, the energy policy as well as the energy challenges in the DRC are also presented.Keywords: energy, biomass, hydro power, renewable energy, energy policy, Democratic Republic of Congo
Procedia PDF Downloads 337355 Effects of Cuminum cyminum L. Essential Oil Supplementation on Components of Metabolic Syndrome: A Clinical Trial
Authors: Ashti Morovati, Hushyar Azari, Bahram Pourghassem Gargari
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Objectives and goals: The prevalence of metabolic syndrome (MetS), as a major health burden for societies, is increasing. This clinical trial was conducted to evaluate the effects of CuEO supplementation on anthropometric indices, systolic and diastolic blood pressure, blood glucose level, insulin resistance and serum lipid level in patients suffering from MetS. Methods: This was a randomized, triple‐blind, placebo‐controlled clinical trial in which 56 patients with MetS aged 18–60 years who fulfilled the eligibility criteria were randomly allocated to an intervention or a control group. Inclusion criteria for the study were comprised of diagnosis of MetS according to the new International Federation of Diabetes. The exclusion criteria were defined as: taking herbal supplements, use of drugs having evident interaction with cumin such as anti‐depressant drugs, vitamin D, omega 3, selenium, zinc, smoking, pregnancy, or breastfeeding, suffering from cancer, having any history of gastrointestinal and hepatic, cardiovascular, thyroid and kidney disorders, and menopause. 75 mg CuEO or placebo soft gels were administered three times daily to the participants for eight weeks. The soft gel consumption was checked by asking the participants to bring the medication containers in the follow‐up visits at the 4th and the 8th weeks of the study. Data pertaining to blood pressure, height, weight, waist circumference, hip circumference and BMI, as well as food consumption were collected at the beginning and end of the study. Fasting blood samples ( glucose, triglyceride, total cholesterol, HDL-cholesterol and LDL-cholesterol) were obtained and biochemical measurements were assessed at the beginning and end of the study. Results: At eight weeks, a total of 44 patients completed this study. Except for diastolic blood pressure (DBP), the other assessed variables were not significantly different between the two groups. In intra group analysis, placebo and CuEO groups both had insignificant decrements in DBP (mean difference [MD] with 95% CI: −3.31 [−7.11, 0.47] and −1.77 [−5.95, 2.40] mmHg, respectively). However, DBP was significantly lower in CuEO compared with the placebo group at the end of study (81.41 ± 5.88 vs. 84.09 ± 5.54 mmHg, MD with 95% CI: −3.98 [−7.60, −0.35] mmHg, p < .05). Conclusions: The results of this study indicated that CuEO does not have any effect on MetS components, except for DBP in patients with MetS.Keywords: blood pressure, fasting blood glucose, lipid profile, waist circumference
Procedia PDF Downloads 151354 Evaluating Forecasting Strategies for Day-Ahead Electricity Prices: Insights From the Russia-Ukraine Crisis
Authors: Alexandra Papagianni, George Filis, Panagiotis Papadopoulos
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The liberalization of the energy market and the increasing penetration of fluctuating renewables (e.g., wind and solar power) have heightened the importance of the spot market for ensuring efficient electricity supply. This is further emphasized by the EU’s goal of achieving net-zero emissions by 2050. The day-ahead market (DAM) plays a key role in European energy trading, accounting for 80-90% of spot transactions and providing critical insights for next-day pricing. Therefore, short-term electricity price forecasting (EPF) within the DAM is crucial for market participants to make informed decisions and improve their market positioning. Existing literature highlights out-of-sample performance as a key factor in assessing EPF accuracy, with influencing factors such as predictors, forecast horizon, model selection, and strategy. Several studies indicate that electricity demand is a primary price determinant, while renewable energy sources (RES) like wind and solar significantly impact price dynamics, often lowering prices. Additionally, incorporating data from neighboring countries, due to market coupling, further improves forecast accuracy. Most studies predict up to 24 steps ahead using hourly data, while some extend forecasts using higher-frequency data (e.g., half-hourly or quarter-hourly). Short-term EPF methods fall into two main categories: statistical and computational intelligence (CI) methods, with hybrid models combining both. While many studies use advanced statistical methods, particularly through different versions of traditional AR-type models, others apply computational techniques such as artificial neural networks (ANNs) and support vector machines (SVMs). Recent research combines multiple methods to enhance forecasting performance. Despite extensive research on EPF accuracy, a gap remains in understanding how forecasting strategy affects prediction outcomes. While iterated strategies are commonly used, they are often chosen without justification. This paper contributes by examining whether the choice of forecasting strategy impacts the quality of day-ahead price predictions, especially for multi-step forecasts. We evaluate both iterated and direct methods, exploring alternative ways of conducting iterated forecasts on benchmark and state-of-the-art forecasting frameworks. The goal is to assess whether these factors should be considered by end-users to improve forecast quality. We focus on the Greek DAM using data from July 1, 2021, to March 31, 2022. This period is chosen due to significant price volatility in Greece, driven by its dependence on natural gas and limited interconnection capacity with larger European grids. The analysis covers two phases: pre-conflict (January 1, 2022, to February 23, 2022) and post-conflict (February 24, 2022, to March 31, 2022), following the Russian-Ukraine conflict that initiated an energy crisis. We use the mean absolute percentage error (MAPE) and symmetric mean absolute percentage error (sMAPE) for evaluation, as well as the Direction of Change (DoC) measure to assess the accuracy of price movement predictions. Our findings suggest that forecasters need to apply all strategies across different horizons and models. Different strategies may be required for different horizons to optimize both accuracy and directional predictions, ensuring more reliable forecasts.Keywords: short-term electricity price forecast, forecast strategies, forecast horizons, recursive strategy, direct strategy
Procedia PDF Downloads 8353 The Influence of C Element on the Phase Transformation in Weldment of Complex Stainless Steels 2507/316/316L
Authors: Lin Dong-Yih, Yang S. M., Huang B. W., Lian J. A.
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Super duplex stainless steel has excellent mechanical properties and corrosion resistance. It becomes important structural material as its application has been extended to the fields such as renewable energy and the chemical industry because of its excellent properties. As examples are offshore wind power, solar cell machinery, and pipes in the chemical industry. The mechanical properties and corrosion resistance of super duplex stainless steel can be eliminated by welding due to the precipitation of the hard and brittle σ phase, which is rich of chromium, and molybdenum elements. This paper studies the influence of carbon element on the phase transformation of -ferrite and σ phase in 2507 super duplex stainless steel. The 2507 will be under argon gas protection welded with 316 and 316L extra low carbon stainless steel separately. The microstructural phases of stainless steels before and after welding, in fusion, heat affected zones, and base material will be studied via X-ray, OM, SEM, EPMA i.e. their quantity, size, distribution, and morphology. The influences of diffusion by carbon element will be compared according to the microstructures, hardness, and corrosion tests.Keywords: complex stainless steel, welding, phase formation, carbon element, sigma phase, delta ferrite
Procedia PDF Downloads 99352 Carbon Nitride Growth on ZnO Architectures for Enhanced Photoelectrochemical Water Splitting Application
Authors: Špela Hajduk, Sean P. Berglund, Matejka Podlogar, Goran Dražić, Fatwa F. Abdi, Zorica C. Orel, Menny Shalom
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Graphitic carbon nitride materials (g-CN) have emerged as an attractive photocatalyst and electrocatalyst for photo and electrochemical water splitting reaction, due to their environmental benignity nature and suitable band gap. Many approaches were introduced to enhance the photoactivity and electronic properties of g-CN and resulted in significant changes in the electronic and catalytic properties. Here we demonstrate the synthesis of thin and homogenous g-CN layer on highly ordered ZnO nanowire (NW) substrate by growing a seeding layer of small supramolecular assemblies on the nanowires. The new synthetic approach leads to the formation of thin g-CN layer (~3 nm) without blocking all structure. Two different deposition methods of carbon nitride were investigated and will be presented. The amount of loaded carbon nitride significantly influences the PEC activity of hybrid material and all the ZnO/g-CNx electrodes show great improvement in photoactivity. The chemical structure, morphology and optical properties of the deposited g-CN were fully characterized by various techniques as X-ray powder spectroscopy (XRD), scanning electron microscopy (SEM), focused ion beam scanning electron microscopy (FIB-SEM), high-resolution scanning microscopy (HR-TEM) and X-ray photoelectron spectroscopy (XPS).Keywords: carbon nitride, photoanode, solar water splitting, zinc oxide
Procedia PDF Downloads 196351 Color Conversion Films with CuInS2/ZnS Quantum Dots Embedded Polystyrene Nanofibers by Electrospinning Process
Authors: Wonkyung Na, Namhun Kim, Heeyeop Chae
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Quantum dots (QDs) are getting attentions due to their excellent optical properties in display, solar cell, biomolecule detection and lighting applications. Energy band gap can be easilty controlled by controlling their size and QDs are proper to apply in light-emitting-diode(LED) and lighting application, especially. Typically cadmium (Cd) containing QDs show a narrow photoluminescence (PL) spectrum and high quantum yield. However, Cd is classified as a hazardous materials and the use of Cd is being tightly regulated under 100ppm level in many countries.InP and CuInS2 (CIS) are being investigated as Cd-free QD materials and it is recently demonstrated that the performance of those Cd-free QDs is comparable to their Cd-based rivals.Due to a broad emission spectrum, CuInS2 QDs are also proper to be applied to white LED.4 For the lighting applications, the QD should be made in forms of color conversion films. Various film processes are reported with QDs in polymer matrixes. In this work, we synthesized the CuInS2 (CIS) QDs and QD embedded polystyrene color conversion films were fabricated for white color emission with electro-spinning process. As a result, blue light from blue LED is converted to white light with high color rendering index (CRI) of 72 by the color conversion films.Keywords: CuInS2/ZnS, electro-spinning, color conversion films, white light emitting diodes
Procedia PDF Downloads 813350 Influence of Different Light Levels in Amaryllis (Hippeastrum X hybridum Hort.) Development and Flowering
Authors: Regina Maria M. Castilho, Isabela M. Morita, Ana Carolina T. Malavolta, Maximiliano K. Pagliarini
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An essential factor for flower production is solar radiation, which is part of plant vital processes. As excess as shortage of light can harm the development of the culture leading to loss in product quality, Unfeasible or decreasing their commercial value. The objective of this research was to evaluate different light levels and their influence on Amaryllis (Hippeastrum X hybridum Hort.) development and flowering. The experiment was conducted at UNESP, São Paulo State, Brazil from August to October 2014. The bulbs were placed in black vases of 1.2 L filled with commercial substrate and divided into 4 different lighting environments (treatments): T1–greenhouse, T2–greenhouse with shade cloth (50%), T3–low lights indoor (until 500 lx) and T4–medium lights indoor (between 500–1000 lx). The used design was completely randomized with ten repetitions and three vessels (bulbs), totalling 30 vessels (bulbs) per treatment. The evaluated characteristics were: Chlorophyll content, number of leaves, length of leaf, number of simultaneous rods, rod length, rod diameter, number of flowers, flowers diameter, beginning of flowering and flowering duration. The results showed that in greenhouse provided Amaryllis better quality plants.Keywords: açucena, bulbs, light, ornamental plants
Procedia PDF Downloads 454349 Sports Activities and their Impact on Disability
Authors: Ajved Ahmed
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This research paper explores the intricate relationship between sports activities and disability, aiming to shed light on the multifaceted impacts of sports participation on individuals with disabilities. As the world grapples with the challenges posed by the growing population of people with disabilities, understanding the role of sports in their lives becomes increasingly important. The paper begins by providing a comprehensive overview of the diverse forms of disabilities, emphasizing the wide spectrum of physical, sensory, and cognitive impairments. It then delves into the benefits of sports activities for individuals with disabilities, highlighting the profound physical, psychological, and social advantages that engagement in sports can offer. These benefits encompass improved physical fitness, enhanced self-esteem and mental well-being, increased social integration, and a sense of empowerment and independence. Furthermore, the paper examines the barriers and challenges that individuals with disabilities often encounter when attempting to participate in sports activities, ranging from inaccessible facilities to societal prejudices and stereotypes. It underscores the critical role of inclusive sports programs, adaptive equipment, and policy initiatives in overcoming these barriers and fostering an environment where everyone can enjoy the benefits of sports. Through a comprehensive review of existing research and case studies, the paper also explores specific sports and their suitability for various types of disabilities. It discusses adapted sports like wheelchair basketball, blind soccer, and para-swimming, showcasing how these tailored activities not only accommodate disabilities but also promote excellence and competition at the highest levels. Additionally, the research paper delves into the economic and societal implications of increased sports participation among individuals with disabilities. It explores the potential for greater inclusion in the workforce, reduced healthcare costs, and the fostering of a more inclusive and accepting society. This research paper underscores the profound impact of sports activities on individuals with disabilities, highlighting their potential to improve physical health, mental well-being, and social integration. It calls for continued efforts to break down barriers and promote inclusive sports programs to ensure that everyone, regardless of their abilities, can access the transformative power of sports. Ultimately, this study contributes to a broader understanding of disability and sports, emphasizing the importance of inclusivity and accessibility in creating a more equitable and healthier society.Keywords: sports and health, sports and disability, curing disability through sports, health benefits of sports
Procedia PDF Downloads 62348 Efficient Solid Oxide Electrolysers for Syn-Gas Generation Using Renewable Energy
Authors: G. Kaur, A. P. Kulkarni, S. Giddey
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Production of fuels and chemicals using renewable energy is a promising way for large-scale energy storage and export. Solid oxide electrolysers (SOEs) integrated with renewable source of energy can produce 'Syngas' H₂/CO from H₂O/CO₂ in the desired ratio for further conversion to liquid fuels. As only a waste CO₂ from industrial and power generation processes is utilized in these processes, this approach is CO₂ neutral compared to using fossil fuel feedstock. In addition, the waste heat from industrial processes or heat from solar thermal concentrators can be effectively utilised in SOEs to further reduce the electrical requirements by up to 30% which boosts overall energy efficiency of the process. In this paper, the electrochemical performance of various novel steam/CO₂ reduction electrodes (cathode) would be presented. The efficiency and lifetime degradation data for single cells and a stack would be presented along with the response of cells to variable electrical load input mimicking the intermittent nature of the renewable energy sources. With such optimisation, newly developed electrodes have been tested for 500+ hrs with Faraday efficiency (electricity to fuel conversion efficiency) up to 95%, and thermal efficiency in excess of 70% based upon energy content of the syngas produced.Keywords: carbon dioxide, steam conversion, electrochemical system, energy storage, fuel production, renewable energy
Procedia PDF Downloads 237347 Museums: The Roles of Lighting in Design
Authors: Fernanda S. Oliveira
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The architectural science of lighting has been mainly concerned with technical aspects and has tended to ignore the psychophysical. There is a growing evidence that adopting passive design solutions may contribute to higher satisfaction. This is even more important in countries with higher solar radiation, which should take advantage of favourable daylighting conditions. However, in art museums, the same light that stimulates vision can also cause permanent damage to the exhibits. Not only the visitors want to see the objects, but also to understand their nature and the artist’s intentions. This paper examines the hypothesis that the more varied and exciting the lighting (and particularly the daylight) in museums rooms, over space and time, the more likely it is that visitors will stay longer, enjoy their experience and be willing to return. This question is not often considered in museums that privilege artificial lighting neglecting the various qualities of daylight other than its capacity to illuminate spaces. The findings of this paper show that daylight plays an important role in museum design, affecting how visitors perceive the exhibition space, as well as contributing to their overall enjoyment in the museum. Rooms with high luminance means were considered more pleasant (r=.311, p<.05) and cheerful (r=.349, p<.05). Lighting conditions also have a direct effect on the phenomenon of museum fatigue with the overall room quality showing an effect on how tired visitors reported to be (r=.421, p<.01). The control and distribution of daylight in museums can therefore contribute to create pleasant conditions for learning, entertainment and amusement, so that visitors are willing to return.Keywords: daylight, comfort, museums, luminance, visitor
Procedia PDF Downloads 486346 Assessment of the Impacts of Climate Change on Watershed Runoff Using Soil and Water Assessment Tool Model in Southeast Nigeria
Authors: Samuel Emeka Anarah, Kingsley Nnaemeka Ogbu, Obasi Arinze
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Quantifying the hydrological response due to changes in climate change is imperative for proper management of water resources within a watershed. The impact of climate change on the hydrology of the Upper Ebony River (UER) watershed, South East Nigeria, was studied using the Soil and Water Assessment Tool (SWAT) hydrological model. A climatological time series analysis from 1985 - 2014 using non-parametric test showed significant negative trends in precipitation and relative humidity trend while minimum and maximum temperature, solar radiation and wind speed showed significant positive trends. Future hypothetical land-use change scenarios (Scenarios 1, 2, 3 and 4) representing urbanization and conversion of forest to agricultural land were combined with future downscaled climate model (CSIRO-Mk3-6-0) and simulated in SWAT model. Relative to the Baseline scenario (2005 - 2014), the results showed a decrease in streamflow by 10.29%, 26.20%, 11.80% and 26.72% for Scenarios 1, 2, 3, and 4 respectively. Model results suggest development of adaptation strategies to cope with the predicted hydrological conditions under future climate change in the watershed.Keywords: climate change, hydrology, runoff, SWAT model
Procedia PDF Downloads 143345 CFD Modelling and Thermal Performance Analysis of Ventilated Double Skin Roof Structure
Authors: A. O. Idris, J. Virgone, A. I. Ibrahim, D. David, E. Vergnault
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In hot countries, the major challenge is the air conditioning. The increase in energy consumption by air conditioning stems from the need to live in more comfortable buildings, which is understandable. But in Djibouti, one of the countries with the most expensive electricity in the world, this need is exacerbated by an architecture that is inappropriate and unsuitable for climatic conditions. This paper discusses the design of the roof which is the surface receiving the most solar radiation. The roof determines the general behavior of the building. The study presents Computational Fluid Dynamics (CFD) modeling and analysis of the energy performance of a double skin ventilated roof. The particularity of this study is that it considers the climate of Djibouti characterized by hot and humid conditions in winter and very hot and humid in summer. Roof simulations are carried out using the Ansys Fluent software to characterize the flow and the heat transfer induced in the ventilated roof in steady state. This modeling is carried out by comparing the influence of several parameters such as the internal emissivity of the upper surface, the thickness of the insulation of the roof and the thickness of the ventilated channel on heat gain through the roof. The energy saving potential compared to the current construction in Djibouti is also presented.Keywords: building, double skin roof, CFD, thermo-fluid analysis, energy saving, forced convection, natural convection
Procedia PDF Downloads 263344 Analysis of the Air Pollution Behavior Registered at MACAM Net Using DOAS, Associated with High Pollution Episodes
Authors: Francisca Rojas Martínez, T. Pedro Oyola
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The combination of the geographical and meteorological conditions of the Santiago basin are unfavorable for the circulation of atmospheric pollution, especially in the autumn and winter months. The problem of environmental pollution in the Metropolitan Region has been studied since the 1960s because the city has presented high pollution levels for most of the year, levels that have even been compared with those in cities in developed countries, This implies serious consequences for the health of the population. Two of the most important gasses present in the contamination are NO2, and O3, the highest concentrations of nitrogen dioxide are measured during the winter, in addition, it is considered as a great contribution to the fine fraction of particulate matter and as a precursor of tropospheric ozone. On the other hand, tropospheric ozone is a pollutant of photochemical origin and is strongly enhanced by solar radiation, which is why its presence in the atmosphere is more significant in the spring and summer. The measurements were made at 3 different places in Santiago, and were used different equipment; a DOAS for gasses measures, SIMCA for Black Carbon Measure and the MACAM net for particulate matter and meteorological condition. The results shows an important relation between height and presence of pollution gasses, and additionally, pollution episodes are in common low temperature (< 10 °C) and high relative humidity (> 80%), which are factors that allows the air suspension of particulate matter and focus NH4+ and NO3-.Keywords: black carbon, DOAS, episodes, high pollution, simca
Procedia PDF Downloads 278343 Optimization and Feasibility Analysis of a PV/Wind/ Battery Hybrid Energy Conversion
Authors: Doaa M. Atia, Faten H. Fahmy, Ninet M. A. El-Rahman, Hassan T. Dorra
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In this paper, the optimum design for renewable energy system powered an aquaculture pond was determined. Hybrid Optimization Model for Electric Renewable (HOMER) software program, which is developed by U.S National Renewable Energy Laboratory (NREL), is used for analyzing the feasibility of the stand-alone and hybrid system in this study. HOMER program determines whether renewable energy resources satisfy hourly electric demand or not. The program calculates energy balance for every 8760 hours in a year to simulate operation of the system. This optimization compares the demand for the electrical energy for each hour of the year with the energy supplied by the system for that hour and calculates the relevant energy flow for each component in the model. The essential principle is to minimize the total system cost while HOMER ensures control of the system. Moreover the feasibility analysis of the energy system is also studied. Wind speed, solar irradiance, interest rate and capacity shortage are the parameters which are taken into consideration. The simulation results indicate that the hybrid system is the best choice in this study, yielding lower net present cost. Thus, it provides higher system performance than PV or wind stand-alone systems.Keywords: wind stand-alone system, photovoltaic stand-alone system, hybrid system, optimum system sizing, feasibility, cost analysis
Procedia PDF Downloads 340342 Two-Stage Launch Vehicle Trajectory Modeling for Low Earth Orbit Applications
Authors: Assem M. F. Sallam, Ah. El-S. Makled
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This paper presents a study on the trajectory of a two stage launch vehicle. The study includes dynamic responses of motion parameters as well as the variation of angles affecting the orientation of the launch vehicle (LV). LV dynamic characteristics including state vector variation with corresponding altitude and velocity for the different LV stages separation, as well as the angle of attack and flight path angles are also discussed. A flight trajectory study for the drop zone of first stage and the jettisoning of fairing are introduced in the mathematical modeling to study their effect. To increase the accuracy of the LV model, atmospheric model is used taking into consideration geographical location and the values of solar flux related to the date and time of launch, accurate atmospheric model leads to enhancement of the calculation of Mach number, which affects the drag force over the LV. The mathematical model is implemented on MATLAB based software (Simulink). The real available experimental data are compared with results obtained from the theoretical computation model. The comparison shows good agreement, which proves the validity of the developed simulation model; the maximum error noticed was generally less than 10%, which is a result that can lead to future works and enhancement to decrease this level of error.Keywords: launch vehicle modeling, launch vehicle trajectory, mathematical modeling, Matlab- Simulink
Procedia PDF Downloads 277341 Design and Implementation of a Counting and Differentiation System for Vehicles through Video Processing
Authors: Derlis Gregor, Kevin Cikel, Mario Arzamendia, Raúl Gregor
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This paper presents a self-sustaining mobile system for counting and classification of vehicles through processing video. It proposes a counting and classification algorithm divided in four steps that can be executed multiple times in parallel in a SBC (Single Board Computer), like the Raspberry Pi 2, in such a way that it can be implemented in real time. The first step of the proposed algorithm limits the zone of the image that it will be processed. The second step performs the detection of the mobile objects using a BGS (Background Subtraction) algorithm based on the GMM (Gaussian Mixture Model), as well as a shadow removal algorithm using physical-based features, followed by morphological operations. In the first step the vehicle detection will be performed by using edge detection algorithms and the vehicle following through Kalman filters. The last step of the proposed algorithm registers the vehicle passing and performs their classification according to their areas. An auto-sustainable system is proposed, powered by batteries and photovoltaic solar panels, and the data transmission is done through GPRS (General Packet Radio Service)eliminating the need of using external cable, which will facilitate it deployment and translation to any location where it could operate. The self-sustaining trailer will allow the counting and classification of vehicles in specific zones with difficult access.Keywords: intelligent transportation system, object detection, vehicle couting, vehicle classification, video processing
Procedia PDF Downloads 323340 Global Voltage Harmonic Index for Measuring Harmonic Situation of Power Grids: A Focus on Power Transformers
Authors: Alireza Zabihi, Saeed Peyghami, Hossein Mokhtari
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With the increasing deployment of renewable power plants, such as solar and wind, it is crucial to measure the harmonic situation of the grid. This paper proposes a global voltage harmonic index to measure the harmonic situation of the power grid with a focus on power transformers. The power electronics systems used to connect these plants to the network can introduce harmonics, leading to increased losses, reduced efficiency, false operation of protective relays, and equipment damage due to harmonic intensifications. The proposed index considers the losses caused by harmonics in power transformers which are of great importance and value to the network, providing a comprehensive measure of the harmonic situation of the grid. The effectiveness of the proposed index is evaluated on a real-world distribution network, and the results demonstrate its ability to identify the harmonic situation of the network, particularly in relation to power transformers. The proposed index provides a comprehensive measure of the harmonic situation of the grid, taking into account the losses caused by harmonics in power transformers. The proposed index has the potential to support power companies in optimizing their power systems and to guide researchers in developing effective mitigation strategies for harmonics in the power grid.Keywords: global voltage harmonic index, harmonics, power grid, power quality, power transformers, renewable energy
Procedia PDF Downloads 127339 Effects of Bleaching Procedures on Dentine Sensitivity
Authors: Suhayla Reda Al-Banai
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Problem Statement: Tooth whitening was used for over one hundred and fifty year. The question concerning the whiteness of teeth is a complex one since tooth whiteness will vary from individual to individual, dependent on age and culture, etc. Tooth whitening following treatment may be dependent on the type of whitening system used to whiten the teeth. There are a few side-effects to the process, and these include tooth sensitivity and gingival irritation. Some individuals may experience no pain or sensitivity following the procedure. Purpose: To systematically review the available published literature until 31st December 2021 to identify all relevant studies for inclusion and to determine whether there was any evidence demonstrating that the application of whitening procedures resulted in the tooth sensitivity. Aim: Systematically review the available published works of literature to identify all relevant studies for inclusion and to determine any evidence demonstrating that application of 10% & 15% carbamide peroxide in tooth whitening procedures resulted in tooth sensitivity. Material and Methods: Following a review of 70 relevant papers from searching both electronic databases (OVID MEDLINE and PUBMED) and hand searching of relevant written journals, 49 studies were identified, 42 papers were subsequently excluded, and 7 studies were finally accepted for inclusion. The extraction of data for inclusion was conducted by two reviewers. The main outcome measures were the methodology and assessment used by investigators to evaluate tooth sensitivity in tooth whitening studies. Results: The reported evaluation of tooth sensitivity during tooth whitening procedures was based on the subjective response of subjects rather than a recognized methodology for evaluating. One of the problems in evaluating was the lack of homogeneity in study design. Seven studies were included. The studies included essential features namely: randomized group, placebo controls, doubleblind and single-blind. Drop-out was obtained from two of included studies. Three of the included studies reported sensitivity at the baseline visit. Two of the included studies mentioned the exclusion criteria Conclusions: The results were inconclusive due to: Limited number of included studies, the study methodology, and evaluation of DS reported. Tooth whitening procedures adversely affect both hard and soft tissues in the oral cavity. Sideeffects are mild and transient in nature. Whitening solutions with greater than 10% carbamide peroxide causes more tooth sensitivity. Studies using nightguard vital bleaching with 10% carbamide peroxide reported two side effects tooth sensitivity and gingival irritation, although tooth sensitivity was more prevalent than gingival irritationKeywords: dentine, sensitivity, bleaching, carbamide peroxde
Procedia PDF Downloads 70338 Thermal Behavior of a Ventilated Façade Using Perforated Ceramic Bricks
Authors: Helena López-Moreno, Antoni Rodríguez-Sánchez, Carmen Viñas-Arrebola, Cesar Porras-Amores
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The ventilated façade has great advantages when compared to traditional façades as it reduces the air conditioning thermal loads due to the stack effect induced by solar radiation in the air chamber. Optimizing energy consumption by using a ventilated façade can be used not only in newly built buildings but also it can be implemented in existing buildings, opening the field of implementation to energy building retrofitting works. In this sense, the following three prototypes of façade where designed, built and further analyzed in this research: non-ventilated façade (NVF); slightly ventilated façade (SLVF) and strongly ventilated façade (STVF). The construction characteristics of the three facades are based on the Spanish regulation of building construction “Technical Building Code”. The façades have been monitored by type-k thermocouples in a representative day of the summer season in Madrid (Spain). Moreover, an analysis of variance (ANOVA) with repeated measures, studying the thermal lag in the ventilated and no-ventilated façades has been designed. Results show that STVF façade presents higher levels of thermal inertia as the thermal lag reduces up to 100% (daily mean) compared to the non-ventilated façade. In addition, the statistical analysis proves that an increase of the ventilation holes size in STVF façades does not improve the thermal lag significantly (p > 0.05) when compared to the SLVF façade.Keywords: ventilated façade, energy efficiency, thermal behavior, statistical analysis
Procedia PDF Downloads 492337 The Effect of Acute Consumption of a Nutritional Supplement Derived from Vegetable Extracts Rich in Nitrate on Athletic Performance
Authors: Giannis Arnaoutis, Dimitra Efthymiopoulou, Maria-Foivi Nikolopoulou, Yannis Manios
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AIM: Nitrate-containing supplements have been used extensively as ergogenic in many sports. However, extract fractions from plant-based nutritional sources high in nitrate and their effect on athletic performance, has not been systematically investigated. The purpose of the present study was to examine the possible effect of acute consumption of a “smart mixture” from beetroot and rocket on exercise capacity. MATERIAL & METHODS: 12 healthy, nonsmoking, recreationally active, males (age: 25±4 years, % fat: 15.5±5.7, Fat Free Mass: 65.8±5.6 kg, VO2 max: 45.46.1 mL . kg -1 . min -1) participated in a double-blind, placebo-controlled trial study, in a randomized and counterbalanced order. Eligibility criteria for participation in this study included normal physical examination, and absence of any metabolic, cardiovascular, or renal disease. All participants completed a time to exhaustion cycling test at 75% of their maximum power output, twice. The subjects consumed either capsules containing 360 mg of nitrate in total or placebo capsules, in the morning, under fasted state. After 3h of passive recovery the performance test followed. Blood samples were collected upon arrival of the participants and 3 hours after the consumption of the corresponding capsules. Time until exhaustion, pre- and post-test lactate concentrations, and rate of perceived exertion for the same time points were assessed. RESULTS: Paired-sample t-test analysis found a significant difference in time to exhaustion between the trial with the nitrate consumption versus placebo [16.1±3.0 Vs 13.5±2.6 min, p=0.04] respectively. No significant differences were observed for the concentrations of lactic acid as well as for the values in the Borg scale between the two trials (p>0.05). CONCLUSIONS: Based on the results of the present study, it appears that a nutritional supplement derived from vegetable extracts rich in nitrate, improves athletic performance in recreationally active young males. However, the precise mechanism is not clear and future studies are needed. Acknowledgment: This research has been co‐financed by the European Regional Development Fund of the European Union and Greek national funds through the Operational Program Competitiveness, Entrepreneurship and Innovation, under the call RESEARCH – CREATE – INNOVATE (project code:T2EDK-00843).Keywords: sports performance, ergogenic supplements, nitrate, extract fractions
Procedia PDF Downloads 66336 Impact of Landuse Change on Surface Temperature in Ibadan, Nigeria
Authors: Abegunde Linda, Adedeji Oluwatola
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It has become increasingly evident that large developments influence the climate within the immediate region and there are concerns that rising temperatures over developed areas could have negative impact and increase living discomfort within city boundaries. Temperature trends in Ibadan city have received minor attention, yet the area has experienced heavy urban expansion between 1972 and 2014. This research aims at examining the impact of landuse change on temperature knowing that the built environment absorbs and stores solar energy, the temperature in cities can be several degrees higher than in adjacent rural areas. This is known as the urban heat island (UHI) effect. The Landsat imagery were used to examine the landuse change for a time period of 42years (1972-2014) and Land surface temperature (LST) was obtained by converting the thermal band to a surface temperature map and zonal statistic analyses was further used to examine the relationship between landuse and temperature emission. The results showed that the settlement area increased by 200km2 while the area covered by vegetation also reduced to about 42.6% during the study period. The spatial and temporal trends of temperature are related to the gradual change in urban landcover and the settlement area has the highest emission of land surface temperature. This research provides useful insight into the temporal behavior of the Ibadan city.Keywords: landuse, LST, remote sensing, UHI
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