Search results for: motility analysis of human spermatozoa
23712 A Socio-Technical Approach to Cyber-Risk Assessment
Authors: Kitty Kioskli, Nineta Polemi
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Evaluating the levels of cyber-security risks within an enterprise is most important in protecting its information system, services and all its digital assets against security incidents (e.g. accidents, malicious acts, massive cyber-attacks). The existing risk assessment methodologies (e.g. eBIOS, OCTAVE, CRAMM, NIST-800) adopt a technical approach considering as attack factors only the capability, intention and target of the attacker, and not paying attention to the attacker’s psychological profile and personality traits. In this paper, a socio-technical approach is proposed in cyber risk assessment, in order to achieve more realistic risk estimates by considering the personality traits of the attackers. In particular, based upon principles from investigative psychology and behavioural science, a multi-dimensional, extended, quantifiable model for an attacker’s profile is developed, which becomes an additional factor in the cyber risk level calculation.Keywords: attacker, behavioural models, cyber risk assessment, cybersecurity, human factors, investigative psychology, ISO27001, ISO27005
Procedia PDF Downloads 15123711 StockTwits Sentiment Analysis on Stock Price Prediction
Authors: Min Chen, Rubi Gupta
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Understanding and predicting stock market movements is a challenging problem. It is believed stock markets are partially driven by public sentiments, which leads to numerous research efforts to predict stock market trend using public sentiments expressed on social media such as Twitter but with limited success. Recently a microblogging website StockTwits is becoming increasingly popular for users to share their discussions and sentiments about stocks and financial market. In this project, we analyze the text content of StockTwits tweets and extract financial sentiment using text featurization and machine learning algorithms. StockTwits tweets are first pre-processed using techniques including stopword removal, special character removal, and case normalization to remove noise. Features are extracted from these preprocessed tweets through text featurization process using bags of words, N-gram models, TF-IDF (term frequency-inverse document frequency), and latent semantic analysis. Machine learning models are then trained to classify the tweets' sentiment as positive (bullish) or negative (bearish). The correlation between the aggregated daily sentiment and daily stock price movement is then investigated using Pearson’s correlation coefficient. Finally, the sentiment information is applied together with time series stock data to predict stock price movement. The experiments on five companies (Apple, Amazon, General Electric, Microsoft, and Target) in a duration of nine months demonstrate the effectiveness of our study in improving the prediction accuracy.Keywords: machine learning, sentiment analysis, stock price prediction, tweet processing
Procedia PDF Downloads 14323710 Influence of Mooring Conditions on Side-By-Side Offloading System Safety Performance
Authors: Liu Shengnan, Sun Liping, Zhu Jianxun
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Based on three dimensional potential flow theory, hydrodynamic response analysis is carried on the multi floating bodies system composed of FPSO moored with yoke and shuttle tanker. It considered hydrodynamic interaction between FPSO and shuttle tanker, interaction between the hull and yoke mooring systems, hawsers, fenders, and then focuses on hawsers of the side-by-side offloading system. The influence of hawsers parameters on system safety is studied in respects of hawser stiffness, length and arrangement. Through analysis in different environment conditions and two typical loading conditions, it can be found that a better safety performance can be achieved through these three ways including enlarging the number of hawsers as well as the stiffness of hawsers, changing the length and arrangement of hawsers.Keywords: yoke mooring, side-by-side offloading, multi floating body, hawser, safety
Procedia PDF Downloads 41923709 Chemical Study of Volatile Organic Compounds (VOCS) from Xylopia aromatica (LAM.) Mart (Annonaceae)
Authors: Vanessa G. P. Severino, JOÃO Gabriel M. Junqueira, Michelle N. G. do Nascimento, Francisco W. B. Aquino, João B. Fernandes, Ana P. Terezan
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The scientific interest in analyzing VOCs represents a significant modern research field as a result of importance in most branches of the present life and industry. Therefore it is extremely important to investigate, identify and isolate volatile substances, since they can be used in different areas, such as food, medicine, cosmetics, perfumery, aromatherapy, pesticides, repellents and other household products through methods for extracting volatile constituents, such as solid phase microextraction (SPME), hydrodistillation (HD), solvent extraction (SE), Soxhlet extraction, supercritical fluid extraction (SFE), stream distillation (SD) and vacuum distillation (VD). The Chemometrics is an area of chemistry that uses statistical and mathematical tools for the planning and optimization of the experimental conditions, and to extract relevant chemical information multivariate chemical data. In this context, the focus of this work was the study of the chemical VOCs by SPME of the specie X. aromatica, in search of constituents that can be used in the industrial sector as well as in food, cosmetics and perfumery, since these areas industrial has a considerable role. In addition, by chemometric analysis, we sought to maximize the answers of this research, in order to search for the largest number of compounds. The investigation of flowers from X. aromatica in vitro and in alive mode proved consistent, but certain factors supposed influence the composition of metabolites, and the chemometric analysis strengthened the analysis. Thus, the study of the chemical composition of X. aromatica contributed to the VOCs knowledge of the species and a possible application.Keywords: chemometrics, flowers, HS-SPME, Xylopia aromatica
Procedia PDF Downloads 34623708 Maternal and Neonatal Outcomes in Women Undergoing Bariatric Surgery: A Systematic Review and Meta-Analysis
Authors: Nicolas Galazis, Nikolina Docheva, Constantinos Simillis, Kypros Nicolaides
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Background: Obese women are at increased risk for many pregnancy complications, and bariatric surgery (BS) before pregnancy has shown to improve some of these. Objectives: To review the current literature and quantitatively assess the obstetric and neonatal outcomes in pregnant women who have undergone BS. Search Strategy: MEDLINE, EMBASE and Cochrane databases were searched using relevant keywords to identify studies that reported on pregnancy outcomes after BS. Selection Criteria: Pregnancy outcome in firstly, women after BS compared to obese or BMI-matched women with no BS and secondly, women after BS compared to the same or different women before BS. Only observational studies were included. Data Collection and Analysis: Two investigators independently collected data on study characteristics and outcome measures of interest. These were analysed using the random effects model. Heterogeneity was assessed and sensitivity analysis was performed to account for publication bias. Main Results: The entry criteria were fulfilled by 17 non-randomised cohort or case-control studies, including seven with high methodological quality scores. In the BS group, compared to controls, there was a lower incidence of preeclampsia (OR, 0.45, 95% CI, 0.25-0.80; p=0.007), GDM (OR, 0.47, 95% CI, 0.40-0.56; P<0.001) and large neonates (OR 0.46, 95% CI 0.34-0.62; p<0.001) and a higher incidence of small neonates (OR 1.93, 95% CI 1.52-2.44; p<0.001), preterm birth (OR 1.31, 95% CI 1.08-1.58; p=0.006), admission for neonatal intensive care (OR 1.33, 95% CI 1.02-1.72; p=0.03) and maternal anaemia (OR 3.41, 95% CI 1.56-7.44, p=0.002). Conclusions: BS as a whole improves some pregnancy outcomes. Laparoscopic adjustable gastric banding does not appear to increase the rate of small neonates that was seen with other BS procedures. Obese women of childbearing age undergoing BS need to be aware of these outcomes.Keywords: bariatric surgery, pregnancy, preeclampsia, gestational diabetes, birth weight
Procedia PDF Downloads 40123707 Regional Hydrological Extremes Frequency Analysis Based on Statistical and Hydrological Models
Authors: Hadush Kidane Meresa
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The hydrological extremes frequency analysis is the foundation for the hydraulic engineering design, flood protection, drought management and water resources management and planning to utilize the available water resource to meet the desired objectives of different organizations and sectors in a country. This spatial variation of the statistical characteristics of the extreme flood and drought events are key practice for regional flood and drought analysis and mitigation management. For different hydro-climate of the regions, where the data set is short, scarcity, poor quality and insufficient, the regionalization methods are applied to transfer at-site data to a region. This study aims in regional high and low flow frequency analysis for Poland River Basins. Due to high frequent occurring of hydrological extremes in the region and rapid water resources development in this basin have caused serious concerns over the flood and drought magnitude and frequencies of the river in Poland. The magnitude and frequency result of high and low flows in the basin is needed for flood and drought planning, management and protection at present and future. Hydrological homogeneous high and low flow regions are formed by the cluster analysis of site characteristics, using the hierarchical and C- mean clustering and PCA method. Statistical tests for regional homogeneity are utilized, by Discordancy and Heterogeneity measure tests. In compliance with results of the tests, the region river basin has been divided into ten homogeneous regions. In this study, frequency analysis of high and low flows using AM for high flow and 7-day minimum low flow series is conducted using six statistical distributions. The use of L-moment and LL-moment method showed a homogeneous region over entire province with Generalized logistic (GLOG), Generalized extreme value (GEV), Pearson type III (P-III), Generalized Pareto (GPAR), Weibull (WEI) and Power (PR) distributions as the regional drought and flood frequency distributions. The 95% percentile and Flow duration curves of 1, 7, 10, 30 days have been plotted for 10 stations. However, the cluster analysis performed two regions in west and east of the province where L-moment and LL-moment method demonstrated the homogeneity of the regions and GLOG and Pearson Type III (PIII) distributions as regional frequency distributions for each region, respectively. The spatial variation and regional frequency distribution of flood and drought characteristics for 10 best catchment from the whole region was selected and beside the main variable (streamflow: high and low) we used variables which are more related to physiographic and drainage characteristics for identify and delineate homogeneous pools and to derive best regression models for ungauged sites. Those are mean annual rainfall, seasonal flow, average slope, NDVI, aspect, flow length, flow direction, maximum soil moisture, elevation, and drainage order. The regional high-flow or low-flow relationship among one streamflow characteristics with (AM or 7-day mean annual low flows) some basin characteristics is developed using Generalized Linear Mixed Model (GLMM) and Generalized Least Square (GLS) regression model, providing a simple and effective method for estimation of flood and drought of desired return periods for ungauged catchments.Keywords: flood , drought, frequency, magnitude, regionalization, stochastic, ungauged, Poland
Procedia PDF Downloads 59123706 Remote Sensing Application on Snow Products and Analyzing Disaster-Forming Environments Xinjiang, China
Authors: Gulijianati Abake, Ryutaro Tateishi
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Snow is one kind of special underlying surface, has high reflectivity, low thermal conductivity, and snow broth hydrological effect. Every year, frequent snow disaster in Xinjiang causing considerable economic loss and serious damage to towns and farms, such as livestock casualties, traffic jams and other disaster, therefore monitoring SWE (snow volume) in Xinjiang has a great significance. The problems of how this disaster distributes and what disaster-forming environments are important to its occurrence are the most pressing problems in disaster risk assessment and salvage material arrangement. The present study aims 1) to monitor accurate SWE using MODIS, AMSRE, and CMC data, 2) to establish the regularity of snow disaster outbreaks and the important disaster-forming environmental factors. And a spatial autocorrelation analysis method and a canonical correlation analysis method are used to answer these two questions separately, 3) to prepare the way to salvage material arrangements for snow disasters.Keywords: snow water equivalent (snow volume), AMSR-E, CMC snow depth, snow disaster
Procedia PDF Downloads 36623705 Green Public Procurement in Open Access and Traditional Journals: A Comparative Bibliometric Analysis
Authors: Alonso-Cañadas J., Galán-Valdivieso F., Saraite-Sariene L., García-Tabuyo M., Alonso-Morales N.
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Green Public Procurement (GPP) has recently gained attention in the academic and policy arenas since climate change has shown the need to be addressed by both private companies and public entities. Such growing interest motivates this article, aiming to explore the most influential journals, publishers, categories, and topics, as well as the recent trends and future research lines in GPP. Based on the Web of Science database, 578 articles from 2004 to February 2022 devoted to GPP are analyzed using Bibliometrix, an R-tool to perform bibliometric analysis, and Google’s Big Query and Data Studio. This article introduces a variety of findings. First, the most influential journals by far are “Journal of Cleaner Production” and “Sustainability,” differing in that the latter is open access while the former publishes via traditional subscription. This result also occurs regarding the main publishers (Elsevier and MDPI). These features lead us to split the sample into open-access journals and traditional journals to deepen into the similarities and differences between them, confirming that traditional journals exhibit a higher degree of influence in the literature than their open-access counterparts in terms of the number of documents, number of citations and impact (according to the H index). Second, this research also highlights the recent emergence of green-related terms (sustainable, environment) and, parallelly, the increase in categorizing GPP papers in “green” WoS categories, particularly since 2019. Finally, a number of related topics are emerging and will lead the research, such as food security, infrastructures, and implementation barriers of GPP.Keywords: bibliometric analysis, green public procurement, open access, traditional journals
Procedia PDF Downloads 9423704 Traditional Herbal Medicine Used to Treat Infertility in Women by Traditional Practitioner of Malwa Region of Madhya Pradesh, India
Authors: Shweta Shriwas, Sumeet Dwivedi
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Knowledge of use of traditional medicine is as old as human civilization in almost every system of medicine. Traditional practitioner viz., vaidhayas, ojha, hakim have their own herbal therapy in the treatment of infertility among women’s. Infertility is very common in developed and developing countries due to busy life style of women’s. The present study was initiated with an aim to identify medicinal plants resources from traditional practitioners of Malwa region of Madhya Pradesh to treat infertility. An ethnomedicinal study of Malwa region viz., Indore, Dewas, Ratlam, Ujjain, Dhar, Mandsour and Neemuch of Madhya Pradesh, India comprising fifty-seven study site was conducted during Jan-217 to June-2017. During the course of present investigation, the traditional use of medicinal plants for infertility in women was revealed by traditional practitioner. The botanical name, family, local name, part used, habit along with mode of their administration and dose duration were enumerated.Keywords: herbal medicine, infertility, traditional, Malwa, Madhya Pradesh
Procedia PDF Downloads 43023703 Arc Flash Analysis: Technique to Mitigate Fire Incidents in Substations
Authors: M. H. Saeed, M. Rasool, M. A. Jawed
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Arc Flash Analysis has been a subject of great interest since the electrical fire incidents have been reduced to a great extent after the implementation of arc flash study at different sites. An Arc flash in substations is caused by short circuits over the air or other melted conductors and small shrapnel. Arc flash incidents result in the majority of deaths in substations worldwide. Engro Fertilizers Limited (EFERT) site having a mix of vintage non-internal arc rated and modern arc rated switchgears, carried out an arc flash study of the whole site in accordance with NFPA70E standard. The results not only included optimizing site protection coordination settings but also included marking of Shock and Arc flash protection boundaries in all switchgear rooms. Work permit procedures upgradation is also done in accordance with this study to ensure proper arc rated PPEs and arc flash boundaries protocols are fully observed and followed. With the new safety, protocols working on electrical equipment will be much safer than ever before.Keywords: Arc flash, non-internal arc rated, protection coordination, shock boundary
Procedia PDF Downloads 17023702 Ecological and Historical Components of the Cultural Code of the City of Florence as Part of the Edutainment Project Velonotte International
Authors: Natalia Zhabo, Sergey Nikitin, Marina Avdonina, Mariya Nikitina
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The analysis of the activities of one of the events of the international educational and entertainment project Velonotte is provided: an evening bicycle tour with children around Florence. The aim of the project is to develop methods and techniques for increasing the sensitivity of the cycling participants and listeners of the radio broadcasts to the treasures of the national heritage, in this case, to the historical layers of the city and the ecology of the Renaissance epoch. The block of educational tasks is considered, and the issues of preserving the identity of the city are discussed. Methods. The Florentine event was prepared during more than a year. First of all the creative team selected such events of the history of the city which seem to be important for revealing the specifics of the city, its spirit - from antiquity to our days – including the forums of Internet with broad public opinion. Then a route (seven kilometers) was developed, which was proposed to the authorities and organizations of the city. The selection of speakers was conducted according to several criteria: they should be authors of books, famous scientists, connoisseurs in a certain sphere (toponymy, history of urban gardens, art history), capable and willing to talk with participants directly at the points of stops, in order to make a dialogue and so that performances could be organized with their participation. The music was chosen for each part of the itinerary to prepare the audience emotionally. Cards for coloring with images of the main content of each stop were created for children. A site was done to inform the participants and to keep photos, videos and the audio files with speakers’ speech afterward. Results: Held in April 2017, the event was dedicated to the 640th Anniversary of the Filippo Brunelleschi, Florentine architect, and to the 190th anniversary of the publication of Florence guide by Stendhal. It was supported by City of Florence and Florence Bike Festival. Florence was explored to transfer traditional elements of culture, sometimes unfairly forgotten from ancient times to Brunelleschi and Michelangelo and Tschaikovsky and David Bowie with lectures by professors of Universities. Memorable art boards were installed in public spaces. Elements of the cultural code are deeply internalized in the minds of the townspeople, the perception of the city in everyday life and human communication is comparable to such fundamental concepts of the self-awareness of the townspeople as mental comfort and the level of happiness. The format of a fun and playful walk with the ICT support gives new opportunities for enriching the city's cultural code of each citizen with new components, associations, connotations.Keywords: edutainment, cultural code, cycling, sensitization Florence
Procedia PDF Downloads 21123701 Importance-Performance Analysis of Volunteer Tourism in Ethiopia: Host and Guest Case Study
Authors: Zita Fomukong Andam
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With a general objective of evaluating the importance and Performance attributes of Volunteer Tourism in Ethiopia and also specifically intending to rank out the importance to evaluate the competitive performance of Ethiopia to host volunteer tourists, laying them in a four quadrant grid and conduct the IPA Iso-Priority Line comparison of Volunteer Tourism in Ethiopia. From hosts and guests point of view, a deeper research discourse was conducted with a randomly selected 384 guests and 165 hosts in Ethiopia. Findings of the discourse through an exploratory research design on both the hosts and the guests confirm that attributes of volunteer tourism generally and marginally fall in the South East quadrant of the matrix where their importance is relatively higher than their performance counterpart, also referred as ‘Concentrate Here’ quadrant. The fact that there are more items in this particular place in both the host and guest study, where they are highly important, but their relative performance is low, strikes a message that the country has more to do. Another focus point of this study is mapping the scores of attributes regarding the guest and host importance and performance against the Iso-Priority Line. Results of Iso-Priority Line Analysis of the IPA of Volunteer Tourism in Ethiopia from the Host’s Perspective showed that there are no attributes where their importance is exactly the same as their performance. With this being found, the fact that this research design inhabits many characters of exploratory nature, it is not confirmed research output. This paper reserves from prescribing anything to the applied world before further confirmatory research is conducted on the issue and rather calls the scientific community to augment this study through comprehensive, exhaustive, extensive and extended works of inquiry in order to get a refined set of recommended items to the applied world.Keywords: volunteer tourism, competitive performance importance-performance analysis, Ethiopian tourism
Procedia PDF Downloads 21923700 Implementation in Python of a Method to Transform One-Dimensional Signals in Graphs
Authors: Luis Andrey Fajardo Fajardo
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We are immersed in complex systems. The human brain, the galaxies, the snowflakes are examples of complex systems. An area of interest in Complex systems is the chaos theory. This revolutionary field of science presents different ways of study than determinism and reductionism. Here is where in junction with the Nonlinear DSP, chaos theory offer valuable techniques that establish a link between time series and complex theory in terms of complex networks, so that, the study of signals can be explored from the graph theory. Recently, some people had purposed a method to transform time series in graphs, but no one had developed a suitable implementation in Python with signals extracted from Chaotic Systems or Complex systems. That’s why the implementation in Python of an existing method to transform one dimensional chaotic signals from time domain to graph domain and some measures that may reveal information not extracted in the time domain is proposed.Keywords: Python, complex systems, graph theory, dynamical systems
Procedia PDF Downloads 50123699 Adaptive Optimal Controller for Uncertain Inverted Pendulum System: A Dynamic Programming Approach for Continuous Time System
Authors: Dao Phuong Nam, Tran Van Tuyen, Do Trong Tan, Bui Minh Dinh, Nguyen Van Huong
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In this paper, we investigate the adaptive optimal control law for continuous-time systems with input disturbances and unknown parameters. This paper extends previous works to obtain the robust control law of uncertain systems. Through theoretical analysis, an adaptive dynamic programming (ADP) based optimal control is proposed to stabilize the closed-loop system and ensure the convergence properties of proposed iterative algorithm. Moreover, the global asymptotic stability (GAS) for closed system is also analyzed. The theoretical analysis for continuous-time systems and simulation results demonstrate the performance of the proposed algorithm for an inverted pendulum system.Keywords: approximate/adaptive dynamic programming, ADP, adaptive optimal control law, input state stability, ISS, inverted pendulum
Procedia PDF Downloads 18623698 Detection of Antibiotic Resistance Genes and Antibiotic Residues in Plant-based Products
Authors: Morello Sara, Pederiva Sabina, Bianchi Manila, Martucci Francesca, Marchis Daniela, Decastelli Lucia
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Vegetables represent an integral part of a healthy diet due to their valuable nutritional properties and the growth in consumer demand in recent years is particularly remarkable for a diet rich in vitamins and micronutrients. However, plant-based products are involved in several food outbreaks connected to various sources of contamination and quite often, bacteria responsible for side effects showed high resistance to antibiotics. The abuse of antibiotics can be one of the main mechanisms responsible for increasing antibiotic resistance (AR). Plants grown for food use can be contaminated directly by spraying antibiotics on crops or indirectly by treatments with antibiotics due to the use of manure, which may contain both antibiotics and genes of antibiotic resistance (ARG). Antibiotic residues could represent a potential way of human health risk due to exposure through the consumption of plant-based foods. The presence of antibiotic-resistant bacteria might pose a particular risk to consumers. The present work aims to investigate through a multidisciplinary approach the occurrence of ARG by means of a biomolecular approach (PCR) and the prevalence of antibiotic residues using a multi residues LC-MS/MS method, both in different plant-based products. During the period from July 2020 to October 2021, a total of 74 plant samples (33 lettuces and 41 tomatoes) were collected from 57 farms located throughout the Piedmont area, and18 out of 74 samples (11 lettuces and 7 tomatoes) were selected to LC-MS/MS analyses. DNA extracted (ExtractME, Blirt, Poland) from plants used on crops and isolated bacteria were analyzed with 6 sets of end-point multiplex PCR (Qiagen, Germany) to detect the presence of resistance genes of the main antibiotic families, such as tet genes (tetracyclines), bla (β-lactams) and mcr (colistin). Simultaneous detection of 43 molecules of antibiotics belonging to 10 different classes (tetracyclines, sulphonamides, quinolones, penicillins, amphenicols, macrolides, pleuromotilines, lincosamides, diaminopyrimidines) was performed using Exion LC system AB SCIEX coupled to a triple quadrupole mass spectrometer QTRAP 5500 from AB SCIEX. The PCR assays showed the presence of ARG in 57% (n=42): tetB (4.8%; n=2), tetA (9.5%; n=4), tetE (2.4%; n=1), tetL (12%; n=5), tetM (26%; n=11), blaSHV (21.5%; n=9), blaTEM (4.8%; n =2) and blaCTX-M (19%; n=8). In none of the analyzed samples was the mcr gene responsible for colistin resistance detected. Results obtained from LC-MS/MS analyses showed that none of the tested antibiotics appear to exceed the LOQ (100 ppb). Data obtained confirmed the presence of bacterial populations containing antibiotic resistance determinants such as tet gene (tetracycline) and bla genes (beta-lactams), widely used in human medicine, which can join the food chain and represent a risk for consumers, especially with raw products. The presence of traces of antibiotic residues in vegetables, in concentration below the LOQ of the LC-MS/MS method applied, cannot be excluded. In conclusion, traces of antibiotic residues could be a health risk to the consumer due to potential involvement in the spread of AR. PCR represents a useful and effective approach to characterize and monitor AR carried by bacteria from the entire food chain.Keywords: plant-based products, ARG, PCR, antibiotic residues
Procedia PDF Downloads 8323697 Optimal Analysis of Grounding System Design for Distribution Substation
Authors: Thong Lantharthong, Nattchote Rugthaicharoencheep, Att Phayomhom
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This paper presents the electrical effect of two neighboring distribution substation during the construction phase. The size of auxiliary grounding grid have an effect on entire grounding system. The bigger the size of auxiliary grounding grid, the lower the GPR and maximum touch voltage, with the exception that when the two grids are unconnected, i.e. the bigger the size of auxiliary grounding grid, the higher the maximum step voltage. The results in this paper could be served as design guideline of grounding system, and perhaps remedy of some troublesome grounding grids in power distribution’s system. Modeling and simulation is carried out on the Current Distribution Electromagnetic interference Grounding and Soil structure (CDEGS) program. The simulation results exhibit the design and analysis of power system grounding and perhaps could be set as a standard in grounding system design and modification in distribution substations.Keywords: grounding system, touch voltage, step voltage, safety criteria
Procedia PDF Downloads 44223696 A Review of Methods for Handling Missing Data in the Formof Dropouts in Longitudinal Clinical Trials
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Much clinical trials data-based research are characterized by the unavoidable problem of dropout as a result of missing or erroneous values. This paper aims to review some of the various techniques to address the dropout problems in longitudinal clinical trials. The fundamental concepts of the patterns and mechanisms of dropout are discussed. This study presents five general techniques for handling dropout: (1) Deletion methods; (2) Imputation-based methods; (3) Data augmentation methods; (4) Likelihood-based methods; and (5) MNAR-based methods. Under each technique, several methods that are commonly used to deal with dropout are presented, including a review of the existing literature in which we examine the effectiveness of these methods in the analysis of incomplete data. Two application examples are presented to study the potential strengths or weaknesses of some of the methods under certain dropout mechanisms as well as to assess the sensitivity of the modelling assumptions.Keywords: incomplete longitudinal clinical trials, missing at random (MAR), imputation, weighting methods, sensitivity analysis
Procedia PDF Downloads 40323695 Anabasine Intoxication and its Relation to Plant Development Stages
Authors: Thaís T. Valério Caetano, João Máximo De Siqueira, Carlos Alexandre Carollo, Arthur Ladeira Macedo, Vanessa C. Stein
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Nicotiana glauca, commonly known as wild tobacco or tobacco bush, belongs to the Solanaceae family. It is native to South America but has become naturalized in various regions, including Australia, California, Africa, and the Mediterranean. N. glauca is listed in the Global Invasive Species Database (GISD) and the Invasive Species Compendium (CABI). It is known for producing pyridine alkaloids, including anabasine, which is highly toxic. Anabasine is predominantly found in the leaves and can cause severe health issues such as neuromuscular blockade, respiratory arrest, and cardiovascular problems when ingested. Mistaken identity with edible plants like spinach has resulted in food poisoning cases in Israel and Brazil. Anabasine, a minor alkaloid constituent of tobacco, may contribute to tobacco addiction by mimicking or enhancing the effects of nicotine. Therefore, it is essential to investigate the production pattern of anabasine and its relationship to the developmental stages of the plant. This study aimed to establish the relationship between the phenological plant age, cultivation place, and the increase in anabasine concentration, which can lead to human intoxication cases. In this study, N. glauca plants were collected from three different rural areas in Brazil for a year to examine leaves at various stages of development. Samples were also obtained from cultivated plants in Marilândia, Minas Gerais, Brazil, as well as from Divinópolis, Minas Gerais, Brazil, and Arraial do Cabo, Rio de Janeiro, Brazil. In vitro cultivated plants on MS medium were included in the study. The collected leaves were dried, powdered, and stored. Alkaloid extraction was performed using a methanol and water mixture, followed by liquid-liquid extraction with chloroform. The anabasine content was determined using HPLC-DAD analysis with nicotine as a standard. The results indicated that anabasine production increases with the plant's development, peaking in adult leaves during the reproduction phase and declining afterward. In vitro, plants showed similar anabasine production to young leaves. The successful adaptation of N. glauca in new environments poses a global problem, and the correlation between anabasine production and the plant's developmental stages has been understudied. The presence of substances produced by the plant can pose a risk to other species, especially when mistaken for edible plants. The findings from this study shed light on the pattern of anabasine production and its association with plant development, contributing to a better understanding of the potential risks associated with N. glauca and the importance of accurate identification.Keywords: nicotiana glauca graham, global invasive species database, alkaloids, toxic
Procedia PDF Downloads 7023694 Analyzing Business Model Choices and Sustainable Value Capturing: A Multiple Case Study of Sharing Economy Business Models
Authors: Minttu Laukkanen, Janne Huiskonen
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This study investigates the sharing economy business models as examples of the sustainable business models. The aim is to contribute to the limited literature on sharing economy in connection with sustainable business models by explaining sharing economy business models value capturing. Specifically, this research answers the following question: How business model choices affect captured sustainable value? A multiple case study approach is applied in this study. Twenty different successful sharing economy business models focusing on consumer business and covering four main areas, accommodation, mobility, food, and consumer goods, are selected for analysis. The secondary data available on companies’ websites, previous research, reports, and other public documents are used. All twenty cases are analyzed through the sharing economy business model framework and sustainable value analysis framework using qualitative data analysis. This study represents general sharing economy business model value attributes and their specifications, i.e. sustainable value propositions for different stakeholders, and further explains the sustainability impacts of different sharing economy business models through captured and uncaptured value. In conclusion, this study represents how business model choices affect sustainable value capturing through eight business model attributes identified in this study. This paper contributes to the research on sustainable business models and sharing economy by examining how business model choices affect captured sustainable value. This study highlights the importance of careful business model and sustainability impacts analyses including the triple bottom line, multiple stakeholders and value captured and uncaptured perspectives as well as sustainability trade-offs. It is not self-evident that sharing economy business models advance sustainability, and business model choices does matter.Keywords: sharing economy, sustainable business model innovation, sustainable value, value capturing
Procedia PDF Downloads 16323693 Influence of Bra Band Tension and Underwire Angles on Breast Motion
Authors: Cheuk Wing Lee, Kit Lun Yick, Sun Pui Ng, Joanne Yip
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Daily activities and exercise may result in large displacements of the breasts, which lead to breast pain and discomfort. Therefore, a proper bra design and fit can help to control excessive breast motion to prevent the over-stretching of the connective tissues. Nevertheless, bra fit problems, such as excessively high tension of the shoulder straps and a tight underband could have substantially negative effects on the wear comfort and health of the wearer. The purpose of this study is to, therefore, examine the effects of bra band tension on breast displacement. Usually, human wear trials are carried out, but there are inconsistencies during testing. Therefore, a soft manikin torso is used to examine breast displacement at walking speeds of 2.30 km/h and 4.08 km/h. The breast displacement itself is determined by using a VICON motion capture system. The 3D geometric changes of the underwire bra band tension and the corresponding control of breast movement are also analyzed by using a 3D handheld scanner along with Rapidform software. The results indicate that an appropriate bra band tension can help to reduce breast displacement and provide a comfortable angle for the underwire. The findings can be used by designers and bra engineers as a reference source to advance bra design and development.Keywords: bra band, bra features, breast displacement, underwire angle
Procedia PDF Downloads 24623692 Mediterranean Diet, Duration of Admission and Mortality in Elderly, Hospitalized Patients: A Cross-Sectional Study
Authors: Christos Lampropoulos, Maria Konsta, Ifigenia Apostolou, Vicky Dradaki, Tamta Sirbilatze, Irini Dri, Christina Kordali, Vaggelis Lambas, Kostas Argyros, Georgios Mavras
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Objectives: Mediterranean diet has been associated with lower incidence of cardiovascular disease and cancer. The purpose of our study was to examine the hypothesis that Mediterranean diet may protect against mortality and reduce admission duration in elderly, hospitalized patients. Methods: Sample population included 150 patients (78 men, 72 women, mean age 80±8.2). The following data were taken into account in analysis: anthropometric and laboratory data, dietary habits (MedDiet score), patients’ nutritional status [Mini Nutritional Assessment (MNA) score], physical activity (International Physical Activity Questionnaires, IPAQ), smoking status, cause and duration of current admission, medical history (co-morbidities, previous admissions). Primary endpoints were mortality (from admission until 6 months afterwards) and duration of admission, compared to national guidelines for closed consolidated medical expenses. Logistic regression and linear regression analysis were performed in order to identify independent predictors for mortality and admission duration difference respectively. Results: According to MNA, nutrition was normal in 54/150 (36%) of patients, 46/150 (30.7%) of them were at risk of malnutrition and the rest 50/150 (33.3%) were malnourished. After performing multivariate logistic regression analysis we found that the odds of death decreased 30% per each unit increase of MedDiet score (OR=0.7, 95% CI:0.6-0.8, p < 0.0001). Patients with cancer-related admission were 37.7 times more likely to die, compared to those with infection (OR=37.7, 95% CI:4.4-325, p=0.001). According to multivariate linear regression analysis, admission duration was inversely related to Mediterranean diet, since it is decreased 0.18 days on average for each unit increase of MedDiet score (b:-0.18, 95% CI:-0.33 - -0.035, p=0.02). Additionally, the duration of current admission increased on average 0.83 days for each previous hospital admission (b:0.83, 95% CI:0.5-1.16, p<0.0001). The admission duration of patients with cancer was on average 4.5 days higher than the patients who admitted due to infection (b:4.5, 95% CI:0.9-8, p=0.015). Conclusion: Mediterranean diet adequately protects elderly, hospitalized patients against mortality and reduces the duration of hospitalization.Keywords: Mediterranean diet, malnutrition, nutritional status, prognostic factors for mortality
Procedia PDF Downloads 30223691 Evaluation of Biological and Confinement Properties of a Bone Substitute to in Situ Preparation Based on Demineralized Bone Matrix for Bone Tissue Regeneration
Authors: Aura Maria Lopera Echavarria, Angela Maria Lema Perez, Daniela Medrano David, Pedronel Araque Marin, Marta Elena Londoño Lopez
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Bone regeneration is the process by which the formation of new bone is stimulated. Bone fractures can originate at any time due to trauma, infections, tumors, congenital malformations or skeletal diseases. Currently there are different strategies to treat bone defects that in some cases, regeneration does not occur on its own. That is why they are treated with bone substitutes, which provide a necessary environment for the cells to synthesize new bone. The Demineralized Bone Matrix (DBM) is widely used as a bone implant due to its good properties, such as osteoinduction and bioactivity. However, the use of DBM is limited, because its presentation is powder, which is difficult to implant with precision and is susceptible to migrating to other sites through blood flow. That is why the DBM is commonly incorporated into a variety of vehicles or carriers. The objective of this project is to evaluate the bioactive and confinement properties of a bone substitute based on demineralized bone matrix (DBM). Also, structural and morphological properties were evaluated. Bone substitute was obtained from EIA Biomaterials Laboratory of EIA University and the DBM was facilitated by Tissue Bank Foundation. Morphological and structural properties were evaluated by scanning electron microscopy (SEM), X-ray diffraction (DRX) and Fourier transform infrared spectroscopy with total attenuated reflection (FTIR-ATR). Water absorption capacity and degradation were also evaluated during three months. The cytotoxicity was evaluated by the MTT test. The bioactivity of the bone substitute was evaluated through immersion of the samples in simulated body fluid during four weeks. Confinement tests were performed on tibial fragments of a human donor with bone defects of determined size, to ensure that the substitute remains in the defect despite the continuous flow of fluid. According of the knowledge of the authors, the methodology for evaluating samples in a confined environment has not been evaluated before in real human bones. The morphology of the samples showed irregular surface and presented some porosity. DRX confirmed a semi-crystalline structure. The FTIR-ATR determined the organic and inorganic phase of the sample. The degradation and absorption measurements stablished a loss of 3% and 150% in one month respectively. The MTT showed that the system is not cytotoxic. Apatite clusters formed from the first week were visualized by SEM and confirmed by EDS. These calcium phosphates are necessary to stimulate bone regeneration and thanks to the porosity of the developed material, osteinduction and osteoconduction are possible. The results of the in vitro evaluation of the confinement of the material showed that the migration of the bone filling to other sites is negligible, although the samples were subjected to the passage of simulated body fluid. The bone substitute, putty type, showed stability, is bioactive, non-cytotoxic and has handling properties for specialists at the time of implantation. The obtained system allows to maintain the osteoinductive properties of DBM and it can fill completely fractures in any way; however, it does not provide a structural support, that is, it should only be used to treat fractures without requiring a mechanical load.Keywords: bone regeneration, cytotoxicity, demineralized bone matrix, hydrogel
Procedia PDF Downloads 11023690 Assessing Project Performance through Work Sampling and Earned Value Analysis
Authors: Shobha Ramalingam
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The majority of the infrastructure projects are affected by time overrun, resulting in project delays and subsequently cost overruns. Time overrun may vary from a few months to as high as five or more years, placing the project viability at risk. One of the probable reasons noted in the literature for this outcome in projects is due to poor productivity. Researchers contend that productivity in construction has only marginally increased over the years. While studies in the literature have extensively focused on time and cost parameters in projects, there are limited studies that integrate time and cost with productivity to assess project performance. To this end, a study was conducted to understand the project delay factors concerning cost, time and productivity. A case-study approach was adopted to collect rich data from a nuclear power plant project site for two months through observation, interviews and document review. The data were analyzed using three different approaches for a comprehensive understanding. Foremost, a root-cause analysis was performed on the data using Ishikawa’s fish-bone diagram technique to identify the various factors impacting the delay concerning time. Based on it, a questionnaire was designed and circulated to concerned executives, including project engineers and contractors to determine the frequency of occurrence of the delay, which was then compiled and presented to the management for a possible solution to mitigate. Second, a productivity analysis was performed on select activities, including rebar bending and concreting through a time-motion study to analyze product performance. Third, data on cost of construction for three years allowed analyzing the cost performance using earned value management technique. All three techniques allowed to systematically and comprehensively identify the key factors that deter project performance and productivity loss in the construction of the nuclear power plant project. The findings showed that improper planning and coordination between multiple trades, concurrent operations, improper workforce and material management, fatigue due to overtime were some of the key factors that led to delays and poor productivity. The findings are expected to act as a stepping stone for further research and have implications for practitioners.Keywords: earned value analysis, time performance, project costs, project delays, construction productivity
Procedia PDF Downloads 9123689 Capital Punishment: A Paradoxical Wrinkle to the Principles of Ethics and Morality
Authors: Pranav Vaidya
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The recent upheaval of a ballot initiative taken place in California & Los Angeles‘s newspapers shows how the concept of giving Death Penalty obliterates the very soul basis of community and society which rests upon the tripod of values, ethics, and morality. This paper goes on with examining how, by giving death penalties we are, on one hand trying to wipe out those heinous offenders committing such unspeakable crimes against the public; while on the other hand it comes with a devastating effect of corroding and eluding the existence of ethics and morality which is in the very nature of “protecting the life of humankind”. As it can be stated that, by giving capital punishment, we are trying to legitimize an irreversible act of violence by the authority of state and target innocent victims because as long as the human justice is fallible, the risk of executing an innocent can never be eliminated. However, scholars in the legalization of Capital Punishment have argued that the courts should impose punishment befitting the crime so that they could reflect public abhorrence of the crime, create deterrent or rehabilitating effects & deliver the truest form of justice.Keywords: ethics, heinous offenders, morality, unspeakable crimes
Procedia PDF Downloads 27723688 Influence of Major Axis on the Aerodynamic Characteristics of Elliptical Section
Authors: K. B. Rajasekarababu, J. Karthik, G. Vinayagamurthy
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This paper is intended to explain the influence of major axis on aerodynamic characteristics of elliptical section. Many engineering applications such as off shore structures, bridge piers, civil structures and pipelines can be modelled as a circular cylinder but flow over complex bodies like, submarines, Elliptical wing, fuselage, missiles, and rotor blades, in which the parameters such as axis ratio can influence the flow characteristics of the wake and nature of separation. Influence of Major axis in Flow characteristics of elliptical sections are examined both experimentally and computationally in this study. For this research, four elliptical models with varying major axis [*AR=1, 4, 6, 10] are analysed. Experimental works have been conducted in a subsonic wind tunnel. Furthermore, flow characteristics on elliptical model are predicted from k-ε turbulence model using the commercial CFD packages by pressure based transient solver with Standard wall conditions.The analysis can be extended to estimation and comparison of Drag coefficient and Fatigue analysis of elliptical sections.Keywords: elliptical section, major axis, aerodynamic characteristics, k-ε turbulence model
Procedia PDF Downloads 42023687 Optimization of Urea Water Solution Injector for NH3 Uniformity Improvement in Urea-SCR System
Authors: Kyoungwoo Park, Gil Dong Kim, Seong Joon Moon, Ho Kil Lee
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The Urea-SCR is one of the most efficient technologies to reduce NOx emissions in diesel engines. In the present work, the computational prediction of internal flow and spray characteristics in the Urea-SCR system was carried out by using 3D-CFD simulation to evaluate NH3 uniformity index (NH3 UI) and its activation time according to the official New European Driving Cycle (NEDC). The number of nozzle and its diameter, two types of injection directions, and penetration length were chosen as the design variables. The optimal solutions were obtained by coupling the CFD analysis with Taguchi method. The L16 orthogonal array and small-the-better characteristics of the Taguchi method were used, and the optimal values were confirmed to be valid with 95% confidence and 5% significance level through analysis of variance (ANOVA). The results show that the optimal solutions for the NH3 UI and activation time (NH3 UI 0.22) are obtained by 0.41 and 0,125 second, respectively, and their values are improved by 85.0% and 10.7%, respectively, compared with those of the base model.Keywords: computational fluid dynamics, NH3 uniformity index, optimization, Taguchi method, Urea-SCR system, UWS injector
Procedia PDF Downloads 25423686 Nature of Cities: Ontological Dimension of the Urban
Authors: Ana Cristina García-Luna Romero
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This document seeks to reflect on the urban project from its conceptual identity root. In the first instance, a proposal is made on how the city project is sustained from the conceptual root, from the logos: it opens a way to assimilate the imagination; what we imagine becomes a reality. In this way, firstly, the need to use language as a vehicle for transmitting the stories that sustain us as humanity can be deemed as an important social factor that enables us to social behavior. Secondly, the need to attend to the written language as a mechanism of power, as a means to consolidate a dominant ideology or a political position, is raised; as it served to carry out the modernization project, it is therefore addressed differences between the real and the literate city. Thus, the consolidated urban-architectural project is based on logos, the project, and planning. Considering the importance of materiality and its relation to subjective well-being contextualized from a socio-urban approach, we question ourselves into how we can look at something that is doubtful. From a philosophy perspective, the truth is considered to be nothing more than a matter of correspondence between the observer and the observed. To understand beyond the relative of the gaze, it is necessary to expose different perspectives since it depends on the understanding of what is observed and how it is critically analyzed. Therefore, the analysis of materiality, as a political field, takes a proposal based on this research in the principles in transgenesis: principle of communication, representativeness, security, health, malleability, availability of potentiality or development, conservation, sustainability, economy, harmony, stability, accessibility, justice, legibility, significance, consistency, joint responsibility, connectivity, beauty, among others. The (urban) human being acts because he wants to live in a certain way: in a community, in a fair way, with opportunity for development, with the possibility of managing the environment according to their needs, etc. In order to comply with this principle, it is necessary to design strategies from the principles in transgenesis, which must be named, defined, understood, and socialized by the urban being, the companies, and from themselves. In this way, the technical status of the city in the neoliberal present determines extraordinary conditions for reflecting on an almost emergency scenario created by the impact of cities that, far from being limited to resilient proposals, must aim at the reflection of the urban process that the present social model has generated. Therefore, can we rethink the paradigm of the perception of life quality in the current neoliberal model in the production of the character of public space related to the practices of being urban. What we are trying to do within this document is to build a framework to study under what logic the practices of the social system that make sense of the public space are developed, what the implications of the phenomena of the inscription of action and materialization (and its results over political action between the social and the technical system) are and finally, how we can improve the quality of life of individuals from the urban space.Keywords: cities, nature, society, urban quality of life
Procedia PDF Downloads 11623685 The Context of Teaching and Learning Primary Science to Gifted Students: An Analysis of Australian Curriculum and New South Wales Science Syllabus
Authors: Rashedul Islam
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A firmly-validated aim of teaching science is to support student enthusiasm for science learning with an outspread interest in scientific issues in future life. This is in keeping with the recent development in Gifted and Talented Education statement which instructs that gifted students have a renewed interest and natural aptitude in science. Yet, the practice of science teaching leaves many students with the feeling that science is difficult and compared to other school subjects, students interest in science is declining at the final years of the primary school. As a curriculum guides the teaching-learning activities in school, where significant consequences may result from the context of the curricula and syllabi, are a major feature of certain educational jurisdictions in NSW, Australia. The purpose of this study was an exploration of the curriculum sets the context to identify how science education is practiced through primary schools in Sydney, Australia. This phenomenon was explored through document review from two publicly available documents namely: the NSW Science Syllabus K-6, and Australian Curriculum: Foundation - 10 Science. To analyse the data, this qualitative study applied themed content analysis at three different levels, i.e., first cycle coding, second cycle coding- pattern codes, and thematic analysis. Preliminary analysis revealed the phenomenon of teaching-learning practices drawn from eight themes under three phenomena aligned with teachers’ practices and gifted student’s learning characteristics based on Gagné’s Differentiated Model of Gifted and Talent (DMGT). From the results, it appears that, overall, the two documents are relatively well-placed in terms of identifying the context of teaching and learning primary science to gifted students. However, educators need to make themselves aware of the ways in which the curriculum needs to be adapted to meet gifted students learning needs in science. It explores the important phenomena of teaching-learning context to provide gifted students with optimal educational practices including inquiry-based learning, problem-solving, open-ended tasks, creativity in science, higher order thinking, integration, and challenges. The significance of such a study lies in its potential to schools and further research in the field of gifted education.Keywords: teaching primary science, gifted student learning, curriculum context, science syllabi, Australia
Procedia PDF Downloads 41323684 The Effect of Incorporation of Inulin as a Fat Replacer on the Quality of Milk Products Vis-À-Vis Ice Cream
Authors: Harish Kumar Sharma
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The influence of different levels of inulin as a fat replacer on the quality of ice cream was investigated. The physicochemical, rheological and textural properties of control ice cream and ice cream prepared with inulin in different proportions were determined and correlated to the different parameters using Pearson correlation and Principle Component Analysis (PCA). Based on the overall acepectability, ice cream with 4% inulin was found best and was selected for preparation of ice cream with inulin:SPI in different proportions. Compared with control ice cream, Inulin:SPI showed different rheological properties, resulting in significantly higher apparent viscosities, consistency coefficient and greater deviations from Newtonian flow. In addition, both hardness and melting resistance significantly increased with increase in the SPI content in ice cream prepared with inulin: SPI. Also hardness value increased for inulin based ice cream compared to control ice cream but it melted significantly faster than the latter. Colour value significantly decreased in both the cases compared to the control sample. The deliberation shall focus on the effect of incorporation of inulin on the quality of ice-cream.Keywords: fat replacer, inulin, ice cream, viscosity, principal component analysis
Procedia PDF Downloads 37523683 Designing Agricultural Irrigation Systems Using Drone Technology and Geospatial Analysis
Authors: Yongqin Zhang, John Lett
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Geospatial technologies have been increasingly used in agriculture for various applications and purposes in recent years. Unmanned aerial vehicles (drones) fit the needs of farmers in farming operations, from field spraying to grow cycles and crop health. In this research, we conducted a practical research project that used drone technology to design and map optimal locations and layouts of irrigation systems for agriculture farms. We flew a DJI Mavic 2 Pro drone to acquire aerial remote sensing images over two agriculture fields in Forest, Mississippi, in 2022. Flight plans were first designed to capture multiple high-resolution images via a 20-megapixel RGB camera mounted on the drone over the agriculture fields. The Drone Deploy web application was then utilized to develop flight plans and subsequent image processing and measurements. The images were orthorectified and processed to estimate the area of the area and measure the locations of the water line and sprinkle heads. Field measurements were conducted to measure the ground targets and validate the aerial measurements. Geospatial analysis and photogrammetric measurements were performed for the study area to determine optimal layout and quantitative estimates for irrigation systems. We created maps and tabular estimates to demonstrate the locations, spacing, amount, and layout of sprinkler heads and water lines to cover the agricultural fields. This research project provides scientific guidance to Mississippi farmers for a precision agricultural irrigation practice.Keywords: drone images, agriculture, irrigation, geospatial analysis, photogrammetric measurements
Procedia PDF Downloads 67