Search results for: 3D magnetic potential vector and electric scalar potential (A
3745 Fill Rate Window as a Criterion for Spares Allocation
Authors: Michael Dreyfuss, Yahel Giat
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Limited battery range and long recharging times are the greatest obstacles to the successful adoption of electric cars. One of the suggestions to overcome these problems is that carmakers retain ownership of batteries and provide battery swapping service so that customers exchange their depleted batteries for recharged batteries. Motivated by this example, we consider the problem of optimal spares allocation in an exchangeable-item, multi-location repair system. We generalize the standard service measures of fill rate and average waiting time to reflect the fact that customers penalize the service provider only if they have to wait more than a ‘tolerable’ time window. These measures are denoted as the window fill rate and the truncated waiting time, respectively. We find that the truncated waiting time is convex and therefore a greedy algorithm solves the spares allocation problem efficiently. We show that the window fill rate is generally S-shaped and describe an efficient algorithm to find a near-optimal solution and detail a priori and a posteriori upper bounds to the distance from optimum. The theory is complemented with a large scale numerical example demonstrating the spare battery allocation in battery swapping stations.Keywords: convex-concave optimization, exchangeable item, M/G/infinity, multiple location, repair system, spares allocation, window fill rate
Procedia PDF Downloads 4933744 Development of Probiotic Cereal Beverage Using Yeast and Lactic Acid Bacteria Fermentation
Authors: Tuaumelsan Shumye Gebre, Shimelis Admassu Emire, Simon Okomo Aloo, Ramachandran Chelliah, Deog-Hwan Oh
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This study investigates the fermentation of cereal substrates, based on the Ethiopian traditional beverage borde, using probiotic strains of Pediococcus acidilactici WS07 and Saccharomyces cerevisiae AM18 used singly and in co-culture. The pH and titratable acidity, microbial growth dynamics, fermentable sugars profile, volatile organic compounds, total flavonoid content, total phenolic content, antioxidant activity, pancreatic lipase, and α-glucosidase inhibition were analyzed. The viability of every tested strain remained higher than 7 log CFU/mL, satisfying the requirements suggested for probiotic food items. The formation of organic acids is what caused the pH to decrease from roughly 6.6 to 3.8, yet this had no effect on the viability of the microorganisms. The fermentation process, involving P. acidilactici WS07 and S. cerevisiae AM18, led to the utilization of initial carbohydrates, production of organic acids, and generation of volatile compounds that enhance flavor and aroma. Ethanol and glycerol concentrations increased during fermentation, particularly in co-culture assays, contributing to the sensory qualities and stability of the beverages. The primary organic acids generated during fermentation were lactic and acetic acids. A total of 22 volatile substances, such as acids, alcohols, aldehydes, esters, ketones, and other substances, were found. Furthermore, the study demonstrates that fermentation of maize and sorghum with P. acidilactici WS07 and S. cerevisiae AM18 enhances the antioxidant activity and inhibition of pancreatic lipase and α-glucosidase, suggesting potential benefits in managing obesity and diabetes. Therefore, co-cultivating S. cerevisiae AM18 and P. acidilactici WS07 in cereal fermentation led to the successful production of probiotic drinks.Keywords: probiotic beverage, Pediococcus acidilactici, Saccharomyces cerevisiae, volatile compounds
Procedia PDF Downloads 363743 Improved Benzene Selctivity for Methane Dehydroaromatization via Modifying the Zeolitic Pores by Dual Templating Approach
Authors: Deepti Mishra, K. K Pant, Xiu Song Zhao, Muxina Konarova
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Catalytic transformation of simplest hydrocarbon methane into benzene and valuable chemicals over Mo/HZSM-5 has a great economic potential, however, it suffers serious hurdles due to the blockage in the micropores because of extensive coking at high temperature during methane dehydroaromatization (MDA). Under such conditions, it necessitates the design of micro/mesoporous ZSM-5, which has the advantages viz. uniform dispersibility of MoOx species, consequently the formation of active Mo sites in the micro/mesoporous channel and lower carbon deposition because of improved mass transfer rate within the hierarchical pores. In this study, we report a unique strategy to control the porous structures of ZSM-5 through a dual templating approach, utilizing C6 and C12 -surfactants as porogen. DFT studies were carried out to correlate the ZSM-5 framework development using the C6 and C12 surfactants with structure directing agent. The structural and morphological parameters of the synthesized ZSM-5 were explored in detail to determine the crystallinity, porosity, Si/Al ratio, particle shape, size, and acidic strength, which were further correlated with the physicochemical and catalytic properties of Mo modified HZSM-5 catalysts. After Mo incorporation, all the catalysts were tested for MDA reaction. From the activity test, it was observed that C6 surfactant-modified hierarchically porous Mo/HZSM-5(H) showed the highest benzene formation rate (1.5 μmol/gcat. s) and longer catalytic stability up to 270 min of reaction as compared to the conventional microporous Mo/HZSM-5(C). In contrary, C12 surfactant modified Mo/HZSM-5(D) is inferior towards MDA reaction (benzene formation rate: 0.5 μmol/gcat. s). We ascribed that the difference in MDA activity could be due to the hierarchically interconnected meso/microporous feature of Mo/HZSM-5(H) that precludes secondary reaction of coking from benzene and hence contributing substantial stability towards MDA reaction.Keywords: hierarchical pores, Mo/HZSM-5, methane dehydroaromatization, coke deposition
Procedia PDF Downloads 823742 Time Parameter Based for the Detection of Catastrophic Faults in Analog Circuits
Authors: Arabi Abderrazak, Bourouba Nacerdine, Ayad Mouloud, Belaout Abdeslam
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In this paper, a new test technique of analog circuits using time mode simulation is proposed for the single catastrophic faults detection in analog circuits. This test process is performed to overcome the problem of catastrophic faults being escaped in a DC mode test applied to the inverter amplifier in previous research works. The circuit under test is a second-order low pass filter constructed around this type of amplifier but performing a function that differs from that of the previous test. The test approach performed in this work is based on two key- elements where the first one concerns the unique square pulse signal selected as an input vector test signal to stimulate the fault effect at the circuit output response. The second element is the filter response conversion to a square pulses sequence obtained from an analog comparator. This signal conversion is achieved through a fixed reference threshold voltage of this comparison circuit. The measurement of the three first response signal pulses durations is regarded as fault effect detection parameter on one hand, and as a fault signature helping to hence fully establish an analog circuit fault diagnosis on another hand. The results obtained so far are very promising since the approach has lifted up the fault coverage ratio in both modes to over 90% and has revealed the harmful side of faults that has been masked in a DC mode test.Keywords: analog circuits, analog faults diagnosis, catastrophic faults, fault detection
Procedia PDF Downloads 4423741 Chassis Level Control Using Proportional Integrated Derivative Control, Fuzzy Logic and Deep Learning
Authors: Atakan Aral Ormancı, Tuğçe Arslantaş, Murat Özcü
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This study presents the design and implementation of an experimental chassis-level system for various control applications. Specifically, the height level of the chassis is controlled using proportional integrated derivative, fuzzy logic, and deep learning control methods. Real-time data obtained from height and pressure sensors installed in a 6x2 truck chassis, in combination with pulse-width modulation signal values, are utilized during the tests. A prototype pneumatic system of a 6x2 truck is added to the setup, which enables the Smart Pneumatic Actuators to function as if they were in a real-world setting. To obtain real-time signal data from height sensors, an Arduino Nano is utilized, while a Raspberry Pi processes the data using Matlab/Simulink and provides the correct output signals to control the Smart Pneumatic Actuator in the truck chassis. The objective of this research is to optimize the time it takes for the chassis to level down and up under various loads. To achieve this, proportional integrated derivative control, fuzzy logic control, and deep learning techniques are applied to the system. The results show that the deep learning method is superior in optimizing time for a non-linear system. Fuzzy logic control with a triangular membership function as the rule base achieves better outcomes than proportional integrated derivative control. Traditional proportional integrated derivative control improves the time it takes to level the chassis down and up compared to an uncontrolled system. The findings highlight the superiority of deep learning techniques in optimizing the time for a non-linear system, and the potential of fuzzy logic control. The proposed approach and the experimental results provide a valuable contribution to the field of control, automation, and systems engineering.Keywords: automotive, chassis level control, control systems, pneumatic system control
Procedia PDF Downloads 813740 Ecosystem Engineering Strengthens Bottom-Up and Weakens Top-Down Effects via Trait-Mediated Indirect Interactions
Authors: Zhiwei Zhong, Xiaofei Li, Deli Wang
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Ecosystem engineering is a powerful force shaping community structure and ecosystem function. Yet, very little is known about the mechanisms by which engineers affect vital ecosystem processes like trophic interactions. Here, we examine the potential for a herbivore ecosystem engineer, domestic sheep, to affect trophic interactions between the web-building spider Argiope bruennichi, its grasshopper prey Euchorthippus spp., and the grasshoppers’ host plant Leymus chinensis. By integrating small- and large-scale field experiments, we demonstrate that: 1) moderate sheep grazing changed the structure of plant communities by suppressing strongly interacting forbs within a grassland matrix; 2) this change in plant community structure drove interaction modifications between the grasshoppers and their grass host plants and between grasshoppers and their spider predators, and 3) these interaction modifications were entirely mediated by plasticity in grasshopper behavior. Overall, ecosystem engineering by sheep grazing strengthened bottom-up effects and weakened top-down effects via trait-mediated interactions, resulting in a nearly two-fold increase in grasshopper densities. Interestingly, the grasshopper behavioral shifts which reduced spider per capita predation rates in the microcosms did not translate to reduced spider predation rates at the larger system scale because increased grasshopper densities offset behavioral effects at larger scales. Our findings demonstrate that 1) ecosystem engineering can strongly alter trophic interactions, 2) such effects can be driven by cryptic trait-mediated interactions, and 3) the relative importance of trait- versus density effects as measured by microcosm experiments may not reflect the importance of these processes at realistic ecological scales due to scale-dependent interactions.Keywords: bottom-up effects, ecosystem engineering, trait-mediated indirect effects, top-down effects
Procedia PDF Downloads 3573739 Occupational Health and Well-Being of Healthcare Workers at Tertiary Care Hospitals in Lahore, Pakistan: A Comparison of Public and Private Sector
Authors: Mehwish Sarfaraz Ahmad
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Background: There is a prevailing perception in Pakistan that private hospitals offer better services than government hospitals. Unfortunately, Pakistan faces challenges in providing efficient healthcare due to limited resources and management capabilities, resulting in demotivation among healthcare workers. Aim: The purpose of this study was to conduct a comprehensive assessment of the occupational health and well-being of healthcare workers in both public and private sector tertiary care hospitals in Lahore, Pakistan, to compare the well-being of healthcare professionals in these two sectors and investigate the influence of workplace culture and experiences on their overall health. Methods: A cross-sectional study was conducted using a validated International Questionnaire, and data from 440 participants was collected using a stratified random sampling technique from a diverse group of healthcare professionals from the public and private tertiary care hospitals in Lahore, Pakistan. The researcher conducted a comparative analysis using appropriate statistical tests, such as Anova, t-tests, chi-square tests, and regression analysis, to explore potential relationships between various factors. Results: The majority of respondents (70.2%) reported their health as "Good" or "Very good, a small percentage (8.2%) rated their health as "Poor," while 24.1% considered their health as "Fair". 39.6% reported being satisfied with their workplace culture, while a majority of 60.4% indicated being unsatisfied with their workplace culture. Results showed that workplace culture has a positive correlation with the overall health and well-being of healthcare professionals. The study found significant differences in health ratings, prevalence of chronic health conditions, workplace culture, and safety perceptions between healthcare professionals in public and private sector tertiary care hospitals. Conclusion: The study's findings emphasize the significance of promoting a positive workplace culture, ensuring workplace safety, and addressing chronic health conditions among healthcare workers.Keywords: occupational health and well-being, workplace culture, frequency of fatigue, availabity of benefits
Procedia PDF Downloads 683738 A Scoping Review of Psychosocial Interventions for the Survivors and/or Victims of Intimate Partner Violence in Low- and Middle-Income Countries
Authors: Mukondi Nethavhakone
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The high prevalence of violence against women is a global public health problem. Our societies have become dangerous places for women. Women during their child-bearing ages are at a higher risk of experiencing emotional, physical, and sexual violence. What makes it more concerning is that these violent acts are perpetrated by family members or partners, or ex-partners. Intimate Partner Violence (IPV) is associated with long-lasting physical, reproductive, sexual, mental, and maternal health implications. Expectedly women’s mental health would dimmish as a result of experiencing IPV. The burden of violence against women is seen to be heavier in low- and middle-income countries (LMICs) compared to the rest of the world. Countries have committed to eliminating all forms of violence against women through the sustainable development goal, aiming to see changes by the year 2030. As such, various countries have implemented psychosocial interventions of different levels of impact. However, little is known, especially in low- and middle-income countries, with regard to the potential of psychosocial interventions for IPV to improve the mental health outcomes for the survivors and/or victims of IPV. Analysing the risk for IPV through a social-ecological theoretical approach, low- and middle-income countries still readdressing gender inequality which is the cause of intimate partner violence. That is why it is taking time for these countries to shift psychosocial interventions to focus more on the improvement of the mental health of the survivors. It is, therefore, against this backdrop that the researcher intends to undertake a scoping review to understand the nature and characteristics of psychosocial interventions that have been implemented in low- and middle-income countries. With the findings from the scoping review, the researcher aims to develop a conceptual framework that may be a useful resource for healthcare practitioners and researchers in low- and middle-income countries. As this area of research has not been thoroughly reviewed, the results from this scoping will determine whether a systematic review will be justifiable. Additionally, the researcher will identify gaps and opportunities for future research in this area.Keywords: mental health improvement, psychosocial interventions, intimate partner violence, LMICs
Procedia PDF Downloads 1293737 Strategies to Enhance Compliance of Health and Safety Standards at the Selected Mining Industries in Limpopo Province, South Africa: Occupational Health Nurse’s Perspective
Authors: Livhuwani Muthelo
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The health and safety of the miners in the South African mining industry are guided by the regulations and standards which are anticipated to promote a healthy work environment and fatalities. It is of utmost importance for the miners to comply with these regulations/standards to protect themselves from potential occupational health and safety risks, accidents, and fatalities. The purpose of this study was to develop and validate strategies to enhance compliance with the Health and safety standards within the mining industries of Limpopo province in South Africa. A mixed-method exploratory sequential research design was adopted. The population consisted of 5350 miners. Purposive sampling was used to select the participants in the qualitative strand and stratified random sampling in the quantitative strand. Semi-structured interviews were conducted among the occupational health nurse practitioners and the health and safety team. Thematic analysis was used to generate an understanding of the interviews. In the quantitative strand, a survey was conducted using a self-administered questionnaire. Data were analysed using SPSS version 26.0. A descriptive statistical test was used in the analysis of data including frequencies, means, and standard deviation. Cronbach's alpha test was used to measure internal consistency. The integrated results revealed that there are diverse experiences related to health and safety standards compliance among the mineworkers. The main findings were challenges related to leadership compliance and also related to the cost of maintaining safety, Miner's behavior-related challenges; the impact of non-compliance on the overall health of the miners was also described, the conflict between production and safety. Health and safety compliance is not just mere compliance with regulations and standards but a culture that warrants the miners and organization to take responsibility for their behavior and actions towards health and safety. Thus taking responsibility for your well-being and other miners.Keywords: perceptions, compliance, health and safety, legislation, standards, miners
Procedia PDF Downloads 1043736 Representation of Memory of Forced Displacement in Central and Eastern Europe after World War II in Polish and German Cinemas
Authors: Ilona Copik
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The aim of this study is to analyze the representation of memories of the forced displacement of Poles and Germans from the eastern territories in 1945 as depicted by Polish and German feature films between the years 1945-1960. The aftermath of World War II and the Allied agreements concluded at Yalta and Potsdam (1945) resulted in changes in national borders in Central and Eastern Europe and the large-scale transfer of civilians. The westward migration became a symbol of the new post-war division of Europe, new spheres of influence separated by the Iron Curtain. For years it was a controversial topic in both Poland and Germany due to the geopolitical alignment (the socialist East and capitalist West of Europe), as well as the unfinished debate between the victims and perpetrators of the war. The research premise is to take a comparative view of the conflicted cultures of Polish and German memory, to reflect on the possibility of an international dialogue about the past recorded in film images, and to discover the potential of film as a narrative warning against totalitarian inclinations. Until now, films made between 1945 and 1960 in Poland and the German occupation zones have been analyzed mainly in the context of artistic strategies subordinated to ideology and historical politics. In this study, the intention is to take a critical approach leading to the recognition of how films work as collective memory media, how they reveal the mechanisms of memory/forgetting, and what settlement topoi and migration myths they contain. The main hypothesis is that feature films about forced displacement, in addition to the politics of history - separate in each country - reveal comparable transnational individual experiences: the chaos of migration, the trauma of losing one's home, the conflicts accompanying the familiar/foreign, the difficulty of cultural adaptation, the problem of lost identity, etc.Keywords: forced displacement, Polish and German cinema, war victims, World War II
Procedia PDF Downloads 673735 Predicting Response to Cognitive Behavioral Therapy for Psychosis Using Machine Learning and Functional Magnetic Resonance Imaging
Authors: Eva Tolmeijer, Emmanuelle Peters, Veena Kumari, Liam Mason
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Cognitive behavioral therapy for psychosis (CBTp) is effective in many but not all patients, making it important to better understand the factors that determine treatment outcomes. To date, no studies have examined whether neuroimaging can make clinically useful predictions about who will respond to CBTp. To this end, we used machine learning methods that make predictions about symptom improvement at the individual patient level. Prior to receiving CBTp, 22 patients with a diagnosis of schizophrenia completed a social-affective processing task during functional MRI. Multivariate pattern analysis assessed whether treatment response could be predicted by brain activation responses to facial affect that was either socially threatening or prosocial. The resulting models did significantly predict symptom improvement, with distinct multivariate signatures predicting psychotic (r=0.54, p=0.01) and affective (r=0.32, p=0.05) symptoms. Psychotic symptom improvement was accurately predicted from relatively focal threat-related activation across hippocampal, occipital, and temporal regions; affective symptom improvement was predicted by a more dispersed profile of responses to prosocial affect. These findings enrich our understanding of the neurobiological underpinning of treatment response. This study provides a foundation that will hopefully lead to greater precision and tailoring of the interventions offered to patients.Keywords: cognitive behavioral therapy, machine learning, psychosis, schizophrenia
Procedia PDF Downloads 2743734 Fake News Detection for Korean News Using Machine Learning Techniques
Authors: Tae-Uk Yun, Pullip Chung, Kee-Young Kwahk, Hyunchul Ahn
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Fake news is defined as the news articles that are intentionally and verifiably false, and could mislead readers. Spread of fake news may provoke anxiety, chaos, fear, or irrational decisions of the public. Thus, detecting fake news and preventing its spread has become very important issue in our society. However, due to the huge amount of fake news produced every day, it is almost impossible to identify it by a human. Under this context, researchers have tried to develop automated fake news detection using machine learning techniques over the past years. But, there have been no prior studies proposed an automated fake news detection method for Korean news to our best knowledge. In this study, we aim to detect Korean fake news using text mining and machine learning techniques. Our proposed method consists of two steps. In the first step, the news contents to be analyzed is convert to quantified values using various text mining techniques (topic modeling, TF-IDF, and so on). After that, in step 2, classifiers are trained using the values produced in step 1. As the classifiers, machine learning techniques such as logistic regression, backpropagation network, support vector machine, and deep neural network can be applied. To validate the effectiveness of the proposed method, we collected about 200 short Korean news from Seoul National University’s FactCheck. which provides with detailed analysis reports from 20 media outlets and links to source documents for each case. Using this dataset, we will identify which text features are important as well as which classifiers are effective in detecting Korean fake news.Keywords: fake news detection, Korean news, machine learning, text mining
Procedia PDF Downloads 2753733 Biochemical Characterization of CTX-M-15 from Enterobacter cloacae and Designing a Novel Non-β-Lactam-β-Lactamase Inhibitor
Authors: Mohammad Faheem, M. Tabish Rehman, Mohd Danishuddin, Asad U. Khan
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The worldwide dissemination of CTX-M type β-lactamases is a threat to human health. Previously, we have reported the spread of blaCTX-M-15 gene in different clinical strains of Enterobacteriaceae from the hospital settings of Aligarh in north India. In view of the varying resistance pattern against cephalosporins and other β-lactam antibiotics, we intended to understand the correlation between MICs and catalytic activity of CTX-M-15. In this study, steady-state kinetic parameters and MICs were determined on E. coli DH5α transformed with blaCTX-M-15 gene that was cloned from Enterobacter cloacae (EC-15) strain of clinical background. The effect of conventional β-lactamase inhibitors (clavulanic acid, sulbactam and tazobactam) on CTX-M-15 was also studied. We have found that tazobactam is the best among these inhibitors against CTX-M-15. The inhibition characteristic of tazobactam is defined by its very low IC50 value (6 nM), high affinity (Ki = 0.017 µM) and better acylation efficiency (k+2/K9 = 0.44 µM-1s-1). It forms an acyl-enzyme covalent complex, which is quite stable (k+3 = 0.0057 s-1). Since increasing resistance has been reported against conventional b-lactam antibiotic-inhibitor combinations, we aspire to design a non-b-lactam core containing b-lactamase inhibitor. For this, we screened ZINC database and performed molecular docking to identify a potential non-β-lactam based inhibitor (ZINC03787097). The MICs of cephalosporin antibiotics in combination with this inhibitor gave promising results. Steady-state kinetics and molecular docking studies showed that ZINC03787097 is a reversible inhibitor which binds non-covalently to the active site of the enzyme through hydrogen bonds and hydrophobic interactions. Though, it’s IC50 (180 nM) is much higher than tazobactam, it has good affinity for CTX-M-15 (Ki = 0.388 µM). This study concludes that ZINC03787097 compound can be used as seed molecule to design more efficient non-b-lactam containing b-lactamase inhibitor that could evade pre-existing bacterial resistance mechanisms.Keywords: ESBL, non-b-lactam-b-lactamase inhibitor, bioinformatics, biomedicine
Procedia PDF Downloads 2383732 Modeling the Effects of Temperature on Air Pollutant Concentration
Authors: Mustapha Babatunde, Bassam Tawabini, Ole John Nielson
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Air dispersion (AD) models such as AERMOD are important tools for estimating the environmental impacts of air pollutant emissions into the atmosphere from anthropogenic sources. The outcome of these models is significantly linked to the climate condition like air temperature, which is expected to differ in the future due to the global warming phenomenon. With projections from scientific sources of impending changes to the future climate of Saudi Arabia, especially anticipated temperature rise, there is a potential direct impact on the dispersion patterns of air pollutants results from AD models. To our knowledge, no similar studies were carried out in Saudi Arabia to investigate such impact. Therefore, this research investigates the effects of climate temperature change on air quality in the Dammam Metropolitan area, Saudi Arabia, using AERMOD coupled with Station data using Sulphur dioxide (SO2) – as a model air pollutant. The research uses AERMOD model to predict the SO2 dispersion trends on the surrounding area. Emissions from five (5) industrial stacks, on twenty-eight (28) receptors in the study area were considered for the climate period (2010-2019) and future period of mid-century (2040-2060) under different scenarios of elevated temperature profiles (+1oC, + 3oC and + 5oC) across averaging time periods of 1hr, 4hr and 8hr. Results showed that levels of SO2 at the receiving sites under current and simulated future climactic condition fall within the allowable limit of WHO and KSA air quality standards. Results also revealed that the projected rise in temperature would only have mild increment on the SO2 concentration levels. The average increase of SO2 levels were 0.04%, 0.14%, and 0.23% due to the temperature increase of 1, 3, and 5 degrees respectively. In conclusion, the outcome of this work elucidates the degree of the effects of global warming and climate changes phenomena on air quality and can help the policymakers in their decision-making, given the significant health challenges associated with ambient air pollution in Saudi Arabia.Keywords: air quality, sulphur dioxide, global warming, air dispersion model
Procedia PDF Downloads 1313731 Numerical Investigation of Gas Leakage in RCSW-Soil Combinations
Authors: Mahmoud Y. M. Ahmed, Ahmed Konsowa, Mostafa Sami, Ayman Mosallam
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Fukushima nuclear accident (Japan 2011) has drawn attention to the issue of gas leakage from hazardous facilities through building boundaries. The rapidly increasing investments in nuclear stations have made the ability to predict, and prevent, gas leakage a rather crucial issue both environmentally and economically. Leakage monitoring for underground facilities is rather complicated due to the combination of Reinforced Concrete Shear Wall (RCSW) and soil. In the framework of a recent research conducted by the authors, the gas insulation capabilities of RCSW-soil combination have been investigated via a lab-scale experimental work. Despite their accuracy, experimental investigations are expensive, time-consuming, hazardous, and lack for flexibility. Numerically simulating the gas leakage as a fluid flow problem based on Computational Fluid Dynamics (CFD) modeling approach can provide a potential alternative. This novel implementation of CFD approach is the topic of the present paper. The paper discusses the aspects of modeling the gas flow through porous media that resemble the RCSW both isolated and combined with the normal soil. A commercial CFD package is utilized in simulating this fluid flow problem. A fixed RCSW layer thickness is proposed, air is taken as the leaking gas, whereas the soil layer is represented as clean sand with variable properties. The variable sand properties include sand layer thickness, fine fraction ratio, and moisture content. The CFD simulation results almost demonstrate what has been found experimentally. A soil layer attached next to a cracked reinforced concrete section plays a significant role in reducing the gas leakage from that cracked section. This role is found to be strongly dependent on the soil specifications.Keywords: RCSW, gas leakage, Pressure Decay Method, hazardous underground facilities, CFD
Procedia PDF Downloads 4183730 The Optimal Utilization of Centrally Located Land: The Case of the Bloemfontein Show Grounds
Authors: D. F. Coetzee, M. M. Campbell
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The urban environment is constantly expanding and the optimal use of centrally located land is important in terms of sustainable development. Bloemfontein has expanded and this affects land-use functions. The purpose of the study is to examine the possible shift in location of the Bloemfontein show grounds to utilize the space of the grounds more effectively in context of spatial planning. The research method used is qualitative case study research with the case study on the Bloemfontein show grounds. The purposive sample consisted of planners who work or consult in the Bloemfontein area and who are registered with the South African Council for Planners (SACPLAN). Interviews consisting of qualitative open-ended questionnaires were used. When considering relocation the social and economic aspects need to be considered. The findings also indicated a majority consensus that the property can be utilized more effectively in terms of mixed land use. The showground development trust compiled a master plan to ensure that the property is used to its full potential without the relocation of the showground function itself. This Master Plan can be seen as the next logical step for the showground property itself, and it is indeed an attempt to better utilize the land parcel without relocating the show function. The question arises whether the proposed Master Plan is a permanent solution or whether it is merely delaying the relocation of the core showground function to another location. For now, it is a sound solution, making the best out of the situation at hand and utilizing the property more effectively. If the show grounds were to be relocated the researcher proposed a recommendation of mixed-use development, in terms an expansion on the commercial business/retail, together with a sport and recreation function. The show grounds in Bloemfontein are well positioned to capitalize on and to meet the needs of the changing economy, while complimenting the future economic growth strategies of the city if the right plans are in place.Keywords: centrally located land, spatial planning, show grounds, central business district
Procedia PDF Downloads 4143729 Fault Prognostic and Prediction Based on the Importance Degree of Test Point
Authors: Junfeng Yan, Wenkui Hou
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Prognostics and Health Management (PHM) is a technology to monitor the equipment status and predict impending faults. It is used to predict the potential fault and provide fault information and track trends of system degradation by capturing characteristics signals. So how to detect characteristics signals is very important. The select of test point plays a very important role in detecting characteristics signal. Traditionally, we use dependency model to select the test point containing the most detecting information. But, facing the large complicated system, the dependency model is not built so easily sometimes and the greater trouble is how to calculate the matrix. Rely on this premise, the paper provide a highly effective method to select test point without dependency model. Because signal flow model is a diagnosis model based on failure mode, which focuses on system’s failure mode and the dependency relationship between the test points and faults. In the signal flow model, a fault information can flow from the beginning to the end. According to the signal flow model, we can find out location and structure information of every test point and module. We break the signal flow model up into serial and parallel parts to obtain the final relationship function between the system’s testability or prediction metrics and test points. Further, through the partial derivatives operation, we can obtain every test point’s importance degree in determining the testability metrics, such as undetected rate, false alarm rate, untrusted rate. This contributes to installing the test point according to the real requirement and also provides a solid foundation for the Prognostics and Health Management. According to the real effect of the practical engineering application, the method is very efficient.Keywords: false alarm rate, importance degree, signal flow model, undetected rate, untrusted rate
Procedia PDF Downloads 3773728 The Interplay between Autophagy and Macrophages' Polarization in Wound Healing: A Genetic Regulatory Network Analysis
Authors: Mayada Mazher, Ahmed Moustafa, Ahmed Abdellatif
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Background: Autophagy is a eukaryotic, highly conserved catabolic process implicated in many pathophysiologies such as wound healing. Autophagy-associated genes serve as a scaffolding platform for signal transduction of macrophage polarization during the inflammatory phase of wound healing and tissue repair process. In the current study, we report a model for the interplay between autophagy-associated genes and macrophages polarization associated genes. Methods: In silico analysis was performed on 249 autophagy-related genes retrieved from the public autophagy database and gene expression data retrieved from Gene Expression Omnibus (GEO); GSE81922 and GSE69607 microarray data macrophages polarization 199 DEGS. An integrated protein-protein interaction network was constructed for autophagy and macrophage gene sets. The gene sets were then used for GO terms pathway enrichment analysis. Common transcription factors for autophagy and macrophages' polarization were identified. Finally, microRNAs enriched in both autophagy and macrophages were predicated. Results: In silico prediction of common transcription factors in DEGs macrophages and autophagy gene sets revealed a new role for the transcription factors, HOMEZ, GABPA, ELK1 and REL, that commonly regulate macrophages associated genes: IL6,IL1M, IL1B, NOS1, SOC3 and autophagy-related genes: Atg12, Rictor, Rb1cc1, Gaparab1, Atg16l1. Conclusions: Autophagy and macrophages' polarization are interdependent cellular processes, and both autophagy-related proteins and macrophages' polarization related proteins coordinate in tissue remodelling via transcription factors and microRNAs regulatory network. The current work highlights a potential new role for transcription factors HOMEZ, GABPA, ELK1 and REL in wound healing.Keywords: autophagy related proteins, integrated network analysis, macrophages polarization M1 and M2, tissue remodelling
Procedia PDF Downloads 1523727 Motif Search-Aided Screening of the Pseudomonas syringae pv. Maculicola Genome for Genes Encoding Tertiary Alcohol Ester Hydrolases
Authors: M. L. Mangena, N. Mokoena, K. Rashamuse, M. G. Tlou
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Tertiary alcohol ester (TAE) hydrolases are a group of esterases (EC 3.1.1.-) that catalyze the kinetic resolution of TAEs and as a result, they are sought-after for the production of optically pure tertiary alcohols (TAs) which are useful as building blocks for number biologically active compounds. What sets these enzymes apart is, the presence of a GGG(A)X-motif in the active site which appears to be the main reason behind their activity towards the sterically demanding TAEs. The genome of Pseudomonas syringae pv. maculicola (Psm) comprises a multitude of genes that encode esterases. We therefore, hypothesize that some of these genes encode TAE hydrolases. In this study, Psm was screened for TAE hydrolase activity using the linalyl acetate (LA) plate assay and a positive reaction was observed. As a result, the genome of Psm was screened for esterases with a GGG(A)X-motif using the motif search tool and two potential TAE hydrolase genes (PsmEST1 and 2, 1100 and 1000bp, respectively) were identified, PsmEST1 was amplified by PCR and the gene sequenced for confirmation. Analysis of the sequence data with the SingnalP 4.1 server revealed that the protein comprises a signal peptide (22 amino acid residues) on the N-terminus. Primers specific for the gene encoding the mature protein (without the signal peptide) were designed such that they contain NdeI and XhoI restriction sites for directional cloning of the PCR products into pET28a. The gene was expressed in E. coli JM109 (DE3) and the clones screened for TAE hydrolase activity using the LA plate assay. A positive clone was selected, overexpressed and the protein purified using nickel affinity chromatography. The activity of the esterase towards LA was confirmed using thin layer chromatography.Keywords: hydrolases, tertiary alcohol esters, tertiary alcohols, screening, Pseudomonas syringae pv., maculicola genome, esterase activity, linalyl acetate
Procedia PDF Downloads 3553726 Tibial Hemimelia Type VIIa: A Case Report
Authors: M. Medrano, M. D. M. S., L. Younes, M. D.
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Introduction: Incidence of tibial hemimelia is 1:1,000,000. Due to pre-existing case studies and literature, there is now a better understanding of the genetics, etiology and pathoanatomy of tibial hemimelia, but an underlying cause is generally unknown. This presentation aims to discuss a rare, congenital lower limb deficiency observed in a patient in order to identify potential prenatal risk factors and future considerations for the patient’s well-being. Observation: A newborn female child, born full term via spontaneous vaginal delivery after induction of labor to unaffected and non-consanguineous parents. The prenatal course was notable for limited and disjointed prenatal care as well as maternal tobacco and marijuana use, anemia of pregnancy, and inadequate weight gain. Prenatal imaging showed lower extremity deformity with the inability to visualize tibia and bilateral clubfeet in the setting of Intrauterine Growth Restriction (IUGR). The patient presented with right equino varus deformity of the foot and right knee joint deformity. Radiological imaging showed the absence of the right tibia and varus angulation of the right foot with dislocation of the tibiotalar joint. Normal femur with lateral and mild anterior displacement of a wide fibula (Weber Type VIIa). Due to the absence of the patient’s tibia and knee extensor mechanism, the patient was not a candidate for reconstructive surgery and ultimately underwent successful right knee disarticulation. Discussion and Conclusion: By utilizing a retrospective chart review of this case, possible risk factors in prenatal care may be identified and add to existing knowledge on etiology. Hopefully, a cause can be clearly identified in the future and, thus, addressed in the prenatal period. In addition, we can investigate the patient’s well-being and adjustment post-operatively to support outpatient management of an uncommon anomaly.Keywords: Tibial hemimelia, prenatal care, pediatric orthopedics, congenital deformity
Procedia PDF Downloads 1603725 Prospectivity Mapping of Orogenic Lode Gold Deposits Using Fuzzy Models: A Case Study of Saqqez Area, Northwestern Iran
Authors: Fanous Mohammadi, Majid H. Tangestani, Mohammad H. Tayebi
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This research aims to evaluate and compare Geographical Information Systems (GIS)-based fuzzy models for producing orogenic gold prospectivity maps in the Saqqez area, NW of Iran. Gold occurrences are hosted in sericite schist and mafic to felsic meta-volcanic rocks in this area and are associated with hydrothermal alterations that extend over ductile to brittle shear zones. The predictor maps, which represent the Pre-(Source/Trigger/Pathway), syn-(deposition/physical/chemical traps) and post-mineralization (preservation/distribution of indicator minerals) subsystems for gold mineralization, were generated using empirical understandings of the specifications of known orogenic gold deposits and gold mineral systems and were then pre-processed and integrated to produce mineral prospectivity maps. Five fuzzy logic operators, including AND, OR, Fuzzy Algebraic Product (FAP), Fuzzy Algebraic Sum (FAS), and GAMMA, were applied to the predictor maps in order to find the most efficient prediction model. Prediction-Area (P-A) plots and field observations were used to assess and evaluate the accuracy of prediction models. Mineral prospectivity maps generated by AND, OR, FAP, and FAS operators were inaccurate and, therefore, unable to pinpoint the exact location of discovered gold occurrences. The GAMMA operator, on the other hand, produced acceptable results and identified potentially economic target sites. The P-A plot revealed that 68 percent of known orogenic gold deposits are found in high and very high potential regions. The GAMMA operator was shown to be useful in predicting and defining cost-effective target sites for orogenic gold deposits, as well as optimizing mineral deposit exploitation.Keywords: mineral prospectivity mapping, fuzzy logic, GIS, orogenic gold deposit, Saqqez, Iran
Procedia PDF Downloads 1213724 Passive Seismic in Hydrogeological Prospecting: The Case Study from Hard Rock and Alluvium Plain
Authors: Prarabdh Tiwari, M. Vidya Sagar, K. Bhima Raju, Joy Choudhury, Subash Chandra, E. Nagaiah, Shakeel Ahmed
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Passive seismic, a wavefield interferometric imaging, low cost and rapid tool for subsurface investigation is used for various geotechnical purposes such as hydrocarbon exploration, seismic microzonation, etc. With the recent advancement, its application has also been extended to groundwater exploration by means of finding the bedrock depth. Council of Scientific & Industrial Research (CSIR)-National Geophysical Research Institute (NGRI) has experimented passive seismic studies along with electrical resistivity tomography for groundwater in hard rock (Choutuppal, Hyderabad). Passive Seismic with Electrical Resistivity (ERT) can give more clear 2-D subsurface image for Groundwater Exploration in Hard Rock area. Passive seismic data were collected using a Tromino, a three-component broadband seismometer, to measure background ambient noise and processed using GRILLA software. The passive seismic results are found corroborating with ERT (Electrical Resistivity Tomography) results. For data acquisition purpose, Tromino was kept over 30 locations consist recording of 20 minutes at each station. These location shows strong resonance frequency peak, suggesting good impedance contrast between different subsurface layers (ex. Mica rich Laminated layer, Weathered layer, granite, etc.) This paper presents signature of passive seismic for hard rock terrain. It has been found that passive seismic has potential application for formation characterization and can be used as an alternative tool for delineating litho-stratification in an urban condition where electrical and electromagnetic tools cannot be applied due to high cultural noise. In addition to its general application in combination with electrical and electromagnetic methods can improve the interpreted subsurface model.Keywords: passive seismic, resonant frequency, Tromino, GRILLA
Procedia PDF Downloads 1883723 Performance Comparison of Different Regression Methods for a Polymerization Process with Adaptive Sampling
Authors: Florin Leon, Silvia Curteanu
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Developing complete mechanistic models for polymerization reactors is not easy, because complex reactions occur simultaneously; there is a large number of kinetic parameters involved and sometimes the chemical and physical phenomena for mixtures involving polymers are poorly understood. To overcome these difficulties, empirical models based on sampled data can be used instead, namely regression methods typical of machine learning field. They have the ability to learn the trends of a process without any knowledge about its particular physical and chemical laws. Therefore, they are useful for modeling complex processes, such as the free radical polymerization of methyl methacrylate achieved in a batch bulk process. The goal is to generate accurate predictions of monomer conversion, numerical average molecular weight and gravimetrical average molecular weight. This process is associated with non-linear gel and glass effects. For this purpose, an adaptive sampling technique is presented, which can select more samples around the regions where the values have a higher variation. Several machine learning methods are used for the modeling and their performance is compared: support vector machines, k-nearest neighbor, k-nearest neighbor and random forest, as well as an original algorithm, large margin nearest neighbor regression. The suggested method provides very good results compared to the other well-known regression algorithms.Keywords: batch bulk methyl methacrylate polymerization, adaptive sampling, machine learning, large margin nearest neighbor regression
Procedia PDF Downloads 3053722 Drought Detection and Water Stress Impact on Vegetation Cover Sustainability Using Radar Data
Authors: E. Farg, M. M. El-Sharkawy, M. S. Mostafa, S. M. Arafat
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Mapping water stress provides important baseline data for sustainable agriculture. Recent developments in the new Sentinel-1 data which allow the acquisition of high resolution images and varied polarization capabilities. This study was conducted to detect and quantify vegetation water content from canopy backscatter for extracting spatial information to encourage drought mapping activities throughout new reclaimed sandy soils in western Nile delta, Egypt. The performance of radar imagery in agriculture strongly depends on the sensor polarization capability. The dual mode capabilities of Sentinel-1 improve the ability to detect water stress and the backscatter from the structure components improves the identification and separation of vegetation types with various canopy structures from other features. The fieldwork data allowed identifying of water stress zones based on land cover structure; those classes were used for producing harmonious water stress map. The used analysis techniques and results show high capability of active sensors data in water stress mapping and monitoring especially when integrated with multi-spectral medium resolution images. Also sub soil drip irrigation systems cropped areas have lower drought and water stress than center pivot sprinkler irrigation systems. That refers to high level of evaporation from soil surface in initial growth stages. Results show that high relationship between vegetation indices such as Normalized Difference Vegetation Index NDVI the observed radar backscattering. In addition to observational evidence showed that the radar backscatter is highly sensitive to vegetation water stress, and essentially potential to monitor and detect vegetative cover drought.Keywords: canopy backscatter, drought, polarization, NDVI
Procedia PDF Downloads 1453721 Educational Engineering Tool on Smartphone
Authors: Maya Saade, Rafic Younes, Pascal Lafon
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This paper explores the transformative impact of smartphones on pedagogy and presents a smartphone application developed specifically for engineering problem-solving and educational purposes. The widespread availability and advanced capabilities of smartphones have revolutionized the way we interact with technology, including in education. The ubiquity of smartphones allows learners to access educational resources anytime and anywhere, promoting personalized and self-directed learning. The first part of this paper discusses the overall influence of smartphones on pedagogy, emphasizing their potential to improve learning experiences through mobile technology. In the context of engineering education, this paper focuses on the development of a dedicated smartphone application that serves as a powerful tool for both engineering problem-solving and education. The application features an intuitive and user-friendly interface, allowing engineering students and professionals to perform complex calculations and analyses on their smartphones. The smartphone application primarily focuses on beam calculations and serves as a comprehensive beam calculator tailored to engineering education. It caters to various engineering disciplines by offering interactive modules that allow students to learn key concepts through hands-on activities and simulations. With a primary emphasis on beam analysis, this application empowers users to perform calculations for statically determinate beams, statically indeterminate beams, and beam buckling phenomena. Furthermore, the app includes a comprehensive library of engineering formulas and reference materials, facilitating a deeper understanding and practical application of the fundamental principles in beam analysis. By offering a wide range of features specifically tailored for beam calculation, this application provides an invaluable tool for engineering students and professionals looking to enhance their understanding and proficiency in this crucial aspect of a structural engineer.Keywords: mobile devices in education, solving engineering problems, smartphone application, engineering education
Procedia PDF Downloads 663720 Effects of Moisture on Fatigue Behavior of Asphalt Concrete Mixtures Using Four-Point Bending Test
Authors: Mohit Chauhan, Atul Narayan
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Moisture damage is the continuous deterioration of asphalt concrete mixtures by the loss of adhesive bond between the asphalt binder and aggregates, or loss of cohesive bonds within the asphalt binder in the presence of moisture. Moisture has been known to either cause or exacerbates distresses in asphalt concrete pavements. Since moisture would often retain for a relatively long duration at the bottom of asphalt concrete layer, the movement of traffic loading in this saturated condition would cause excess stresses or strains within the mixture. This would accelerate the degradation of the adhesion and cohesion within the mixture and likely to contribute the development of fatigue cracking in asphalt concrete pavements. In view of this, it is important to investigate the effect of moisture on the fatigue behavior of asphalt concrete mixtures. In this study, changes in fatigue characteristics after moisture conditioning were evaluated by conducting four-point beam fatigue tests on dry and moisture conditioned specimens. For this purpose, mixtures with two different types of binders were prepared and saturated with moisture using 700 mm Hg vacuum. Beam specimens, in this way, were taken to a saturation level of 65-75 percent. After preconditioning specimens in this degree of saturation and 60°C for a period of 24 hours, they were subjected to four point beam fatigue tests in strain-controlled mode with a strain amplitude of 400 microstrain. The results were then compared with the fatigue test results obtained with beam specimens that were not subjected to moisture conditioning. Test results show that the conditioning reduces both fatigue life and initial flexural stiffness of specimen significantly. The moisture conditioning was also found to increase the rate of reduction of flexural stiffness. Moreover, it was observed that the fatigue life ratio (FLR), the ratio of the fatigue life of the moisture conditioned sample to that of the dry sample, is significantly lower than the flexural stiffness ratio (FSR). The study indicates that four-point bending test is an appropriate tool with FLR and FSR as the potential parameters for moisture-sensitivity evaluation.Keywords: asphalt concrete, fatigue cracking, moisture damage, preconditioning
Procedia PDF Downloads 1403719 A Collaborative Problem Driven Approach to Design an HR Analytics Application
Authors: L. Atif, C. Rosenthal-Sabroux, M. Grundstein
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The requirements engineering process is a crucial phase in the design of complex systems. The purpose of our research is to present a collaborative problem-driven requirements engineering approach that aims at improving the design of a Decision Support System as an Analytics application. This approach has been adopted to design a Human Resource management DSS. The Requirements Engineering process is presented as a series of guidelines for activities that must be implemented to assure that the final product satisfies end-users requirements and takes into account the limitations identified. For this, we know that a well-posed statement of the problem is “a problem whose crucial character arises from collectively produced estimation and a formulation found to be acceptable by all the parties”. Moreover, we know that DSSs were developed to help decision-makers solve their unstructured problems. So, we thus base our research off of the assumption that developing DSS, particularly for helping poorly structured or unstructured decisions, cannot be done without considering end-user decision problems, how to represent them collectively, decisions content, their meaning, and the decision-making process; thus, arise the field issues in a multidisciplinary perspective. Our approach addresses a problem-driven and collaborative approach to designing DSS technologies: It will reflect common end-user problems in the upstream design phase and in the downstream phase these problems will determine the design choices and potential technical solution. We will thus rely on a categorization of HR’s problems for a development mirroring the Analytics solution. This brings out a new data-driven DSS typology: Descriptive Analytics, Explicative or Diagnostic Analytics, Predictive Analytics, Prescriptive Analytics. In our research, identifying the problem takes place with design of the solution, so, we would have to resort a significant transformations of representations associated with the HR Analytics application to build an increasingly detailed representation of the goal to be achieved. Here, the collective cognition is reflected in the establishment of transfer functions of representations during the whole of the design process.Keywords: DSS, collaborative design, problem-driven requirements, analytics application, HR decision making
Procedia PDF Downloads 2953718 Stability of Pump Station Cavern in Chagrin Shale with Time
Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle
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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.Keywords: Cavern, Chagrin shale, creep, finite element.
Procedia PDF Downloads 3523717 Brain-Computer Interface Based Real-Time Control of Fixed Wing and Multi-Rotor Unmanned Aerial Vehicles
Authors: Ravi Vishwanath, Saumya Kumaar, S. N. Omkar
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Brain-computer interfacing (BCI) is a technology that is almost four decades old, and it was developed solely for the purpose of developing and enhancing the impact of neuroprosthetics. However, in the recent times, with the commercialization of non-invasive electroencephalogram (EEG) headsets, the technology has seen a wide variety of applications like home automation, wheelchair control, vehicle steering, etc. One of the latest developed applications is the mind-controlled quadrotor unmanned aerial vehicle. These applications, however, do not require a very high-speed response and give satisfactory results when standard classification methods like Support Vector Machine (SVM) and Multi-Layer Perceptron (MLPC). Issues are faced when there is a requirement for high-speed control in the case of fixed-wing unmanned aerial vehicles where such methods are rendered unreliable due to the low speed of classification. Such an application requires the system to classify data at high speeds in order to retain the controllability of the vehicle. This paper proposes a novel method of classification which uses a combination of Common Spatial Paradigm and Linear Discriminant Analysis that provides an improved classification accuracy in real time. A non-linear SVM based classification technique has also been discussed. Further, this paper discusses the implementation of the proposed method on a fixed-wing and VTOL unmanned aerial vehicles.Keywords: brain-computer interface, classification, machine learning, unmanned aerial vehicles
Procedia PDF Downloads 2843716 Inactivation of Semicarbazide-Sensitive Amine Oxidase Induces the Phenotypic Switch of Smooth Muscle Cells and Aggravates the Development of Atherosclerotic Lesions
Authors: Miao Zhang, Limin Liu, Feng Zhi, Panpan Niu, Mengya Yang, Xuemei Zhu, Ying Diao, Jun Wang, Ying Zhao
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Background and Aims: Clinical studies have demonstrated that serum semicarbazide-sensitive amine oxidase (SSAO) activities positively correlate with the progression of atherosclerosis. The aim of the present study is to investigate the effect of SSAO inactivation on the development of atherosclerosis. Methods: Female LDLr knockout (KO) mice were given the Western-type diet for 6 and 9 weeks to induce the formation of early and advanced lesions, and semicarbazide (SCZ, 0.125%) was added into the drinking water to inactivate SSAO in vivo. Results: Despite no impact on plasma total cholesterol levels, abrogation of SSAO by SCZ not only resulted in the enlargement of both early (1.5-fold, p=0.0043) and advanced (1.8-fold, p=0.0013) atherosclerotic lesions, but also led to reduced/increased lesion contents of macrophages/smooth muscle cells (SMCs) (macrophage: ~0.74-fold, p=0.0002(early)/0.0016(advanced); SMC: ~1.55-fold, p=0.0003(early) /0.0001(advanced)), respectively. Moreover, SSAO inactivation inhibited the migration of circulating monocytes into peripheral tissues and reduced the amount of circulating Ly6Chigh monocytes (0.7-fold, p=0.0001), which may account for the reduced macrophage content in lesions. In contrast, the increased number of SMCs in lesions of SCZ-treated mice is attributed to an augmented synthetic vascular SMC phenotype switch as evidenced by the increased proliferation of SMCs and accumulation of collagens in vivo. Conclusion: SSAO inactivation by SCZ promotes the phenotypic switch of SMCs and the development of atherosclerosis. The enzymatic activity of SSAO may thus represent a potential target in the prevention and/or treatment of atherosclerosis.Keywords: atherosclerosis, phenotype switch of smooth muscle cells, SSAO/VAP-1, semicarbazide
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