Search results for: building integrated photovoltaics design
13125 Switching of Series-Parallel Connected Modules in an Array for Partially Shaded Conditions in a Pollution Intensive Area Using High Powered MOSFETs
Authors: Osamede Asowata, Christo Pienaar, Johan Bekker
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Photovoltaic (PV) modules may become a trend for future PV systems because of their greater flexibility in distributed system expansion, easier installation due to their nature, and higher system-level energy harnessing capabilities under shaded or PV manufacturing mismatch conditions. This is as compared to the single or multi-string inverters. Novel residential scale PV arrays are commonly connected to the grid by a single DC–AC inverter connected to a series, parallel or series-parallel string of PV panels, or many small DC–AC inverters which connect one or two panels directly to the AC grid. With an increasing worldwide interest in sustainable energy production and use, there is renewed focus on the power electronic converter interface for DC energy sources. Three specific examples of such DC energy sources that will have a role in distributed generation and sustainable energy systems are the photovoltaic (PV) panel, the fuel cell stack, and batteries of various chemistries. A high-efficiency inverter using Metal Oxide Semiconductor Field-Effect Transistors (MOSFETs) for all active switches is presented for a non-isolated photovoltaic and AC-module applications. The proposed configuration features a high efficiency over a wide load range, low ground leakage current and low-output AC-current distortion with no need for split capacitors. The detailed power stage operating principles, pulse width modulation scheme, multilevel bootstrap power supply, and integrated gate drivers for the proposed inverter is described. Experimental results of a hardware prototype, show that not only are MOSFET efficient in the system, it also shows that the ground leakage current issues are alleviated in the proposed inverter and also a 98 % maximum associated driver circuit is achieved. This, in turn, provides the need for a possible photovoltaic panel switching technique. This will help to reduce the effect of cloud movements as well as improve the overall efficiency of the system.Keywords: grid connected photovoltaic (PV), Matlab efficiency simulation, maximum power point tracking (MPPT), module integrated converters (MICs), multilevel converter, series connected converter
Procedia PDF Downloads 12713124 Design and Analysis of Electric Power Production Unit for Low Enthalpy Geothermal Reservoir Applications
Authors: Ildar Akhmadullin, Mayank Tyagi
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The subject of this paper is the design analysis of a single well power production unit from low enthalpy geothermal resources. A complexity of the project is defined by a low temperature heat source that usually makes such projects economically disadvantageous using the conventional binary power plant approach. A proposed new compact design is numerically analyzed. This paper describes a thermodynamic analysis, a working fluid choice, downhole heat exchanger (DHE) and turbine calculation results. The unit is able to produce 321 kW of electric power from a low enthalpy underground heat source utilizing n-Pentane as a working fluid. A geo-pressured reservoir located in Vermilion Parish, Louisiana, USA is selected as a prototype for the field application. With a brine temperature of 126℃, the optimal length of DHE is determined as 304.8 m (1000ft). All units (pipes, turbine, and pumps) are chosen from commercially available parts to bring this project closer to the industry requirements. Numerical calculations are based on petroleum industry standards. The project is sponsored by the Department of Energy of the US.Keywords: downhole heat exchangers, geothermal power generation, organic rankine cycle, refrigerants, working fluids
Procedia PDF Downloads 31513123 Design and Development of E-Commerce Web Application for Shopping Management System
Authors: Siddarth A., Bhoomika K.
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Campuskart is a web-based platform that enables college students to buy and sell various items related to electronics, books, project materials, and electronic gadgets at reasonable prices. The application offers students the opportunity to resell their items at valuable and worthwhile prices, while also providing customers with the chance to purchase items at a lower price than the market price. The forthcoming paper will outline the various processes involved in developing the web application, including the design process, methodology, and overall functioning of the system. It will offer a comprehensive overview of how the platform operates and how it can benefit college students looking for affordable and convenient options for buying and selling various items.Keywords: campuskart, web development, data structures, studentfriendlywebsite
Procedia PDF Downloads 7213122 An Adder with Novel PMOS and NMOS for Ultra Low Power Applications in Deep Submicron Technology
Authors: Ch. Ashok Babu, J. V. R. Ravindra, K. Lalkishore
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Power has became a burning issue in modern VLSI design. As the technology advances especially below 45nm, technology of leakage power became a big problem apart of the dynamic power. This paper presents a full adder with novel PMOS and NMOS which consume less power compare to conventional full adder, DTMOS full adder. This paper shows different types of adders and their power consumption, area, and delay. All the experiments have been carried out using Cadence® Virtuoso® design lay out editor which shows power consumption of different types of adders.Keywords: average power, leakage power, delay, DTMOS, PDP
Procedia PDF Downloads 39013121 New Evaluation Methodology for Solidification Product Durability Assessment
Authors: Bozena Dohnalkova, Jakub Hodul, Rostislav Drochytka, Jana Kosikova
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This paper deals with a proposal of a new methodology for durability assessment of solidification product for its safe further use. The new methodology is based on a review of the current state of assessment of treated waste in Czech Republic and abroad. The aim of the paper is to propose an optimal evaluation methodology for verifying properties of solidification product to ensure its safe further use in building industry.Keywords: solidification, stabilization, durability, waste
Procedia PDF Downloads 42913120 Efficient Synthesis of Thiourea Based Iminothiazoline Heterocycles
Authors: Hummera Rafique, Aamer Saeed
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Thioureas are highly biologically active compounds, as many important applications are associated with this nucleus. They serve as exceptionally versatile building block for the synthesis of wide variety of heterocyclic systems, which also possess extensive range of bioactivities. These thioureas were converted into five-membered heterocycles with imino moiety like ethyl 4-[2-benzamido-4-methylthiazol-3(2H)-yl)]benzoates (2a-j) by base catalyzed cyclization of corresponding thioureas with 2-bromoacetone and triethylamine in good yields.Keywords: ethyl 4-[2-benzamido-4-methylthiazol-3(2H)-yl)]benzoates, ethyl 4-(3-benzoylthioureido) benzoates, antibacterial activity
Procedia PDF Downloads 35513119 Design and Development of Wind Turbine Emulator to Operate with 1.5 kW Induction Generator
Authors: Himani Ratna Dahiya
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This paper contributes to design a Wind Emulator coupled to 1.5 kW Induction generator for Wind Energy Conversion System. A wind turbine emulator (WTE) is important equipment for developing wind energy conversion systems. It offers a controllable test environment that allows the evaluation and improvement of control schemes for electric generators that is hard to achieve with an actual wind turbine since the wind speed varies randomly. In this paper a wind emulator is modeled and simulated using MATLAB. Verification of the simulation results is done by experimental setup using DC motor-Induction generator set, LABVIEW and data acquisition card.Keywords: Wind Turbine Emulator, LABVIEW, matlab, induction generator
Procedia PDF Downloads 59013118 The Effects of Integrating Knowledge Management and e-Learning: Productive Work and Learning Coverage
Authors: Ashraf Ibrahim Awad
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It is important to formulate suitable learning environments ca-pable to be customized according to value perceptions of the university. In this paper, light is shed on the concepts of integration between knowledge management (KM), and e-learning (EL) in the higher education sector of the economy in Abu Dhabi Emirate, United Arab Emirates (UAE). A discussion on and how KM and EL can be integrated and leveraged for effective education and training is presented. The results are derived from the literature and interviews with 16 of the academics in eight universities in the Emirate. The conclusion is that KM and EL have much to offer each other, but this is not yet reflected at the implementation level, and their boundaries are not always clear. Interviews have shown that both concepts perceived to be closely related and, responsibilities for these initiatives are practiced by different departments or units.Keywords: knowledge management, e-learning, learning integration, universities, UAE
Procedia PDF Downloads 50713117 SQL Generator Based on MVC Pattern
Authors: Chanchai Supaartagorn
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Structured Query Language (SQL) is the standard de facto language to access and manipulate data in a relational database. Although SQL is a language that is simple and powerful, most novice users will have trouble with SQL syntax. Thus, we are presenting SQL generator tool which is capable of translating actions and displaying SQL commands and data sets simultaneously. The tool was developed based on Model-View-Controller (MVC) pattern. The MVC pattern is a widely used software design pattern that enforces the separation between the input, processing, and output of an application. Developers take full advantage of it to reduce the complexity in architectural design and to increase flexibility and reuse of code. In addition, we use White-Box testing for the code verification in the Model module.Keywords: MVC, relational database, SQL, White-Box testing
Procedia PDF Downloads 42213116 Discrete Tracking Control of Nonholonomic Mobile Robots: Backstepping Design Approach
Authors: Alexander S. Andreev, Olga A. Peregudova
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In this paper, we propose a discrete tracking control of nonholonomic mobile robots with two degrees of freedom. The electro-mechanical model of a mobile robot moving on a horizontal surface without slipping, with two rear wheels controlled by two independent DC electric, and one front roal wheel is considered. We present back-stepping design based on the Euler approximate discrete-time model of a continuous-time plant. Theoretical considerations are verified by numerical simulation. The work was supported by RFFI (15-01-08482).Keywords: actuator dynamics, back stepping, discrete-time controller, Lyapunov function, wheeled mobile robot
Procedia PDF Downloads 41513115 Interactive Glare Visualization Model for an Architectural Space
Authors: Florina Dutt, Subhajit Das, Matthew Swartz
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Lighting design and its impact on indoor comfort conditions are an integral part of good interior design. Impact of lighting in an interior space is manifold and it involves many sub components like glare, color, tone, luminance, control, energy efficiency, flexibility etc. While other components have been researched and discussed multiple times, this paper discusses the research done to understand the glare component from an artificial lighting source in an indoor space. Consequently, the paper discusses a parametric model to convey real time glare level in an interior space to the designer/ architect. Our end users are architects and likewise for them it is of utmost importance to know what impression the proposed lighting arrangement and proposed furniture layout will have on indoor comfort quality. This involves specially those furniture elements (or surfaces) which strongly reflect light around the space. Essentially, the designer needs to know the ramification of the ‘discomfortable glare’ at the early stage of design cycle, when he still can afford to make changes to his proposed design and consider different routes of solution for his client. Unfortunately, most of the lighting analysis tools that are present, offer rigorous computation and analysis on the back end eventually making it challenging for the designer to analyze and know the glare from interior light quickly. Moreover, many of them do not focus on glare aspect of the artificial light. That is why, in this paper, we explain a novel approach to approximate interior glare data. Adding to that we visualize this data in a color coded format, expressing the implications of their proposed interior design layout. We focus on making this analysis process very fluid and fast computationally, enabling complete user interaction with the capability to vary different ranges of user inputs adding more degrees of freedom for the user. We test our proposed parametric model on a case study, a Computer Lab space in our college facility.Keywords: computational geometry, glare impact in interior space, info visualization, parametric lighting analysis
Procedia PDF Downloads 35013114 The Effects of Damping Devices on Displacements, Velocities and Accelerations of Structures
Authors: Radhwane Boudjelthia
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The most recent earthquakes that occurred in the world and particularly in Algeria, have killed thousands of people and severe damage. The example that is etched in our memory is the last earthquake in the regions of Boumerdes and Algiers (Boumerdes earthquake of May 21, 2003). For all the actors involved in the building process, the earthquake is the litmus test for construction. The goal we set ourselves is to contribute to the implementation of a thoughtful approach to the seismic protection of structures. For many engineers, the most conventional approach protection works (buildings and bridges) the effects of earthquakes is to increase rigidity. This approach is not always effective, especially when there is a context that favors the phenomenon of resonance and amplification of seismic forces. Therefore, the field of earthquake engineering has made significant inroads among others catalyzed by the development of computational techniques in computer form and the use of powerful test facilities. This has led to the emergence of several innovative technologies, such as the introduction of special devices insulation between infrastructure and superstructure. This approach, commonly known as "seismic isolation" to absorb the significant efforts without the structure is damaged and thus ensuring the protection of lives and property. In addition, the restraints to the construction by the ground shaking are located mainly at the supports. With these moves, the natural period of construction is increasing, and seismic loads are reduced. Thus, there is an attenuation of the seismic movement. Likewise, the insulation of the base mechanism may be used in combination with earthquake dampers in order to control the deformation of the insulation system and the absolute displacement of the superstructure located above the isolation interface. On the other hand, only can use these earthquake dampers to reduce the oscillation amplitudes and thus reduce seismic loads. The use of damping devices represents an effective solution for the rehabilitation of existing structures. Given all these acceleration reducing means considered passive, much research has been conducted for several years to develop an active control system of the response of buildings to earthquakes.Keywords: earthquake, building, seismic forces, displacement, resonance, response
Procedia PDF Downloads 12713113 Exploration of Artificial Neural Network and Response Surface Methodology in Removal of Industrial Effluents
Authors: Rakesh Namdeti
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Toxic dyes found in industrial effluent must be treated before being disposed of due to their harmful impact on human health and aquatic life. Thus, Musa acuminata (Banana Leaves) was employed in the role of a biosorbent in this work to get rid of methylene blue derived from a synthetic solution. The effects of five process parameters, such as temperature, pH, biosorbent dosage, and initial methylene blue concentration, using a central composite design (CCD), and the percentage of dye clearance were investigated. The response was modelled using a quadratic model based on the CCD. The analysis of variance revealed the most influential element on experimental design response (ANOVA). The temperature of 44.30C, pH of 7.1, biosorbent dose of 0.3 g, starting methylene blue concentration of 48.4 mg/L, and 84.26 percent dye removal were the best conditions for Musa acuminata (Banana leave powder). At these ideal conditions, the experimental percentage of biosorption was 76.93. The link between the estimated results of the developed ANN model and the experimental results defined the success of ANN modeling. As a result, the study's experimental results were found to be quite close to the model's predicted outcomes.Keywords: Musa acuminata, central composite design, methylene blue, artificial neural network
Procedia PDF Downloads 7613112 Technology Identification, Evaluation and Selection Methodology for Industrial Process Water and Waste Water Treatment Plant of 3x150 MWe Tufanbeyli Lignite-Fired Power Plant
Authors: Cigdem Safak Saglam
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Most thermal power plants use steam as working fluid in their power cycle. Therefore, in addition to fuel, water is the other main input for thermal plants. Water and steam must be highly pure in order to protect the systems from corrosion, scaling and biofouling. Pure process water is produced in water treatment plants having many several treatment methods. Treatment plant design is selected depending on raw water source and required water quality. Although working principle of fossil-fuel fired thermal power plants are same, there is no standard design and equipment arrangement valid for all thermal power plant utility systems. Besides that, there are many other technology evaluation and selection criteria for designing the most optimal water systems meeting the requirements such as local conditions, environmental restrictions, electricity and other consumables availability and transport, process water sources and scarcity, land use constraints etc. Aim of this study is explaining the adopted methodology for technology selection for process water preparation and industrial waste water treatment plant in a thermal power plant project located in Tufanbeyli, Adana Province in Turkey. Thermal power plant is fired with indigenous lignite coal extracted from adjacent lignite reserves. This paper addresses all above-mentioned factors affecting the thermal power plant water treatment facilities (demineralization + waste water treatment) design and describes the ultimate design of Tufanbeyli Thermal Power Plant Water Treatment Plant.Keywords: thermal power plant, lignite coal, pretreatment, demineralization, electrodialysis, recycling, ash dampening
Procedia PDF Downloads 48213111 Renewable Energy and Environment: Design of a Decision Aided Tool for Sustainable Development
Authors: Mustapha Ouardouz, Mina Amharref, Abdessamed Bernoussi
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The future energy, for limited energy resources countries, goes through renewable energies (solar, wind etc.). The renewable energies constitute a major component of the energy strategy to cover a substantial part of the growing needs and contribute to environmental protection by replacing fossil fuels. Indeed, sustainable development involves the promotion of renewable energy and the preservation of the environment by the use of clean energy technologies to limit emissions of greenhouse gases and reducing the pressure exerted on the forest cover. So the impact studies, of the energy use on the environment and farm-related risks are necessary. For that, a global approach integrating all the various sectors involved in such project seems to be the best approach. In this paper we present an approach based on the multi criteria analysis and the realization of one pilot to achieve the development of an innovative geo-intelligent environmental platform. An implementation of this platform will collect, process, analyze and manage environmental data in connection with the nature of used energy in the studied region. As an application we consider a region in the north of Morocco characterized by intense agricultural and industrials activities and using diverse renewable energy. The strategic goals of this platform are; the decision support for better governance, improving the responsiveness of public and private companies connected by providing them in real time with reliable data, modeling and simulation possibilities of energy scenarios, the identification of socio-technical solutions to introduce renewable energies and estimate technical and implantable potential by socio-economic analyzes and the assessment of infrastructure for the region and the communities, the preservation and enhancement of natural resources for better citizenship governance through democratization of access to environmental information, the tool will also perform simulations integrating environmental impacts of natural disasters, particularly those linked to climate change. Indeed extreme cases such as floods, droughts and storms will be no longer rare and therefore should be integrated into such projects.Keywords: renewable energies, decision aided tool, environment, simulation
Procedia PDF Downloads 45913110 Producing Graphical User Interface from Activity Diagrams
Authors: Ebitisam K. Elberkawi, Mohamed M. Elammari
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Graphical User Interface (GUI) is essential to programming, as is any other characteristic or feature, due to the fact that GUI components provide the fundamental interaction between the user and the program. Thus, we must give more interest to GUI during building and development of systems. Also, we must give a greater attention to the user who is the basic corner in the dealing with the GUI. This paper introduces an approach for designing GUI from one of the models of business workflows which describe the workflow behavior of a system, specifically through activity diagrams (AD).Keywords: activity diagram, graphical user interface, GUI components, program
Procedia PDF Downloads 46413109 Nanorods Based Dielectrophoresis for Protein Concentration and Immunoassay
Authors: Zhen Cao, Yu Zhu, Junxue Fu
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Immunoassay, i.e., antigen-antibody reaction, is crucial for disease diagnostics. To achieve the adequate signal of the antigen protein detection, a large amount of sample and long incubation time is needed. However, the amount of protein is usually small at the early stage, which makes it difficult to detect. Unlike cells and DNAs, no valid chemical method exists for protein amplification. Thus, an alternative way to improve the signal is through particle manipulation techniques to concentrate proteins, among which dielectrophoresis (DEP) is an effective one. DEP is a technique that concentrates particles to the designated region through a force created by the gradient in a non-uniform electric field. Since DEP force is proportional to the cube of particle size and square of electric field gradient, it is relatively easy to capture larger particles such as cells. For smaller ones like proteins, a super high gradient is then required. In this work, three-dimensional Ag/SiO2 nanorods arrays, fabricated by an easy physical vapor deposition technique called as oblique angle deposition, have been integrated with a DEP device and created the field gradient as high as of 2.6×10²⁴ V²/m³. The nanorods based DEP device is able to enrich bovine serum albumin (BSA) protein by 1800-fold and the rate has reached 180-fold/s when only applying 5 V electric potential. Based on the above nanorods integrated DEP platform, an immunoassay of mouse immunoglobulin G (IgG) proteins has been performed. Briefly, specific antibodies are immobilized onto nanorods, then IgG proteins are concentrated and captured, and finally, the signal from fluorescence-labelled antibodies are detected. The limit of detection (LoD) is measured as 275.3 fg/mL (~1.8 fM), which is a 20,000-fold enhancement compared with identical assays performed on blank glass plates. Further, prostate-specific antigen (PSA), which is a cancer biomarker for diagnosis of prostate cancer after radical prostatectomy, is also quantified with a LoD as low as 2.6 pg/mL. The time to signal saturation has been significantly reduced to one minute. In summary, together with an easy nanorod fabrication and integration method, this nanorods based DEP platform has demonstrated highly sensitive immunoassay performance and thus poses great potentials in applications for early point-of-care diagnostics.Keywords: dielectrophoresis, immunoassay, oblique angle deposition, protein concentration
Procedia PDF Downloads 10313108 System Transformation: Transitioning towards Low Carbon, Resource Efficient, and Circular Economy for Global Sustainability
Authors: Anthony Halog
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In the coming decades the world that we know today will be drastically transformed. Population and economic growth, particularly in developing countries, are radically changing the demand for food and natural resources. Due to the transformations caused by these megatrends, especially economic growth which is rapidly expanding the middle class and changing consumption patterns worldwide, it is expected that this will result to an increase of approximately 40 percent in the demand for food, water, energy and other resources in the next decades. To fulfill this demand in a sustainable and efficient manner while avoiding food and water scarcity as well as environmental catastrophes in the near future, some industries, particularly the ones involved in food and energy production, have to drastically change its current production systems towards circular and green economy. In Australia, the agri-food industry has played a very important role in the scenario described above. It is one of the major food exporters in the world, supplying fast growing international markets in Asia and the Middle East. Though the Australian food supply chains are economically and technologically developed, it has been facing enduring challenges about its international competitiveness and environmental burdens caused by its production processes. An integrated framework for sustainability assessment is needed to precisely identify inefficiencies and environmental impacts created during food production processes. This research proposes a combination of industrial ecology and systems science based methods and tools intending to develop a novel and useful methodological framework for life cycle sustainability analysis of the agri-food industry. The presentation highlights circular economy paradigm aiming to implement sustainable industrial processes to transform the current industrial model of agri-food supply chains. The results are expected to support government policy makers, business decision makers and other stakeholders involved in agri-food-energy production system in pursuit of green and circular economy. The framework will assist future life cycle and integrated sustainability analysis and eco-redesign of food and other industrial systems.Keywords: circular economy, eco-efficiency, agri-food systems, green economy, life cycle sustainability assessment
Procedia PDF Downloads 28113107 Natural Dyes in Schools. Development of Techniques From Early Childhood as a Tool for Art, Design and Sustainability
Authors: Luciana Marrone
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Natural dyes are a great resource for today's artists and designers providing endless possibilities for design and sustainability. This research and development project focuses on the idea of making these dyeing or painting methodologies reach the widest possible range of students. The main objective is to inform and train, free of charge, teachers and students from different academic institutions, at different levels, kindergarten, primary, secondary, tertiary and university. In this research and dissemination project, in the first instance, institutions from Argentina, Chile, Uruguay, Mexico, Spain, Italy, Colombia, Paraguay, Venezuela, Brazil and Australia joined the project, reaching the grassroots of education from the very beginning. Natural dyes will become part of everyday life for more people, achieving their own colors for art, textiles or any other application. The knowledge of the techniques and resources of the student a fundamental tool, sustainable and opens endless possibilities even in places or homes with few economic resources, thus achieving that natural dyes are not only part of the world of designers but also that they are incorporated from the basics and can thus become a resource applicable in different areas even in places with few economic or development possibilities.Keywords: art, education, natural dyes, sustainability, textile design.
Procedia PDF Downloads 8513106 Bridge Healthcare Access Gap with Artifical Intelligence
Authors: Moshmi Sangavarapu
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The US healthcare industry has undergone tremendous digital transformation in recent years, but critical care access to lower-income ethnicities is still in its nascency. This population has historically showcased substantial hesitation to seek any medical assistance. While the lack of sufficient financial resources plays a critical role, the existing cultural and knowledge barriers also contribute significantly to widening the access gap. It is imperative to break these barriers to ensure timely access to therapeutic procedures that can save important lives! Based on ongoing research, healthcare access barriers can be best addressed by tapping the untapped potential of caregiver communities first. They play a critical role in patients’ diagnoses, building healthcare knowledge and instilling confidence in required therapeutic procedures. Recent technological advancements have opened many avenues by developing smart ways of reaching the large caregiver community. A digitized go-to-market strategy featuring connected media coupled with smart IoT devices and geo-location targeting can be collectively leveraged to reach this key audience group. AI/ML algorithms can be thoroughly trained to identify relevant data signals from users' location and browsing behavior and determine useful marketing touchpoints. The web behavior can be further assimilated with natural language processing to identify contextually relevant interest topics and decipher potential caregivers on digital avenues to serve that brand message. In conclusion, grasping the true health access journey of any lower-income ethnic group is important to design beneficial touchpoints that can alleviate patients’ concerns and allow them to break their own access barriers and opt for timely and quality healthcare.Keywords: healthcare access, market access, diversity barriers, patient journey
Procedia PDF Downloads 5413105 Design of Reconfigurable and Non-reciprocal Metasurface with Independent Controls of Transmission Gain, Attenuation and Phase
Authors: Shi Yu Wang, Qian Wei Zhang, He Li, Hao Han He, Yun Bo Li
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The spatial controls of electromagnetic (EM) waves have always been a research hot spot in recent years. And the rapid development of metasurface-based technologies has provided more freedoms for manipulating the EM waves. Here we propose the design of reconfigurable and non-reciprocal metasurface with independent controls of transmission gain, attenuation and phase. The proposed meta-atom mainly consists of the cascaded textures including the receiving antenna, the middle layer in which the power amplifiers (PAs), programmable attenuator and phase shifter locate, and the transmitting antenna. The programmable attenuator and phase shifter can realize the dynamic controls of transmission amplitude and phase independently, and the PA devices in the meta-atom can actualize the performance of non-reciprocal transmission. The proposed meta-atom is analyzed applying field-circuit co-simulation and a sample of the meta-atom is fabricated and measured under using two standard waveguides. The measured results verify the ability of the independent manipulation for transmission amplitude and phase of the proposed the meta-atom and the design method has been verified very well correspondingly.Keywords: active circuits, independent controls of multiple electromagnetic features, non-reciprocal electromagnetic transmission, reconfigurable and programmable
Procedia PDF Downloads 7913104 Fiber-Reinforced Sandwich Structures Based on Selective Laser Sintering: A Technological View
Authors: T. Häfele, J. Kaspar, M. Vielhaber, W. Calles, J. Griebsch
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The demand for an increasing diversification of the product spectrum associated with the current huge customization desire and subsequently the decreasing unit quantities of each production lot is gaining more and more importance within a great variety of industrial branches, e.g. automotive industry. Nevertheless, traditional product development and production processes (molding, extrusion) are already reaching their limits or fail to address these trends of a flexible and digitized production in view of a product variability up to lot size one. Thus, upcoming innovative production concepts like the additive manufacturing technology basically create new opportunities with regard to extensive potentials in product development (constructive optimization) and manufacturing (economic individualization), but mostly suffer from insufficient strength regarding structural components. Therefore, this contribution presents an innovative technological and procedural conception of a hybrid additive manufacturing process (fiber-reinforced sandwich structures based on selective laser sintering technology) to overcome these current structural weaknesses, and consequently support the design of complex lightweight components.Keywords: additive manufacturing, fiber-reinforced plastics (FRP), hybrid design, lightweight design
Procedia PDF Downloads 29713103 Young People, the Internet and Inequality: What are the Causes and Consequences of Exclusion?
Authors: Albin Wallace
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Part of the provision within educational institutions is the design, commissioning and implementation of ICT facilities to improve teaching and learning. Inevitably, these facilities focus largely on Internet Protocol (IP) based provisions including access to the World Wide Web, email, interactive software and hardware tools. Educators should be committed to the use of ICT to improve learning and teaching as well as to issues relating to the Internet and educational disadvantage, especially with respect to access and exclusion concerns. In this paper I examine some recent research into the issue of inequality and use of the Internet during which I discuss the causes and consequences of exclusion in the context of social inequality, digital literacy and digital inequality, also touching on issues of global inequality.Keywords: inequality, internet, education, design
Procedia PDF Downloads 48813102 Numerical Study for Improving Performance of Air Cooled Proton Exchange Membrane Fuel Cell on the Cathode Channel
Authors: Mohamed Hassan Gundu, Jaeseung Lee, Muhammad Faizan Chinannai, Hyunchul Ju
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In this study, we present the effects of bipolar plate design to control the temperature of the cell and ensure effective water management under an excessive amount of air flow and low humidification conditions in the proton exchange membrane fuel cell (PEMFC). The PEMFC model developed and applied to consider a three type of bipolar plate that is defined by ratio of inlet channel width to outlet channel width. Simulation results show that the design which has narrow gas inlet channel and wide gas outlet channel width (wide coolant inlet channel and narrow coolant outlet channel width) make the relative humidity and water concentration increase in the channel and the catalyst layer. Therefore, this study clearly demonstrates that the dehydration phenomenon can be decreased by using design of bipolar plate with narrow gas inlet channel and wide gas outlet channel width (wide coolant inlet channel and narrow coolant outlet channel width).Keywords: PEMFC, air-cooling, relative humidity, water management, water concentration, oxygen concentration
Procedia PDF Downloads 29413101 A Validation Technique for Integrated Ontologies
Authors: Neli P. Zlatareva
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Ontology validation is an important part of web applications’ development, where knowledge integration and ontological reasoning play a fundamental role. It aims to ensure the consistency and correctness of ontological knowledge and to guarantee that ontological reasoning is carried out in a meaningful way. Existing approaches to ontology validation address more or less specific validation issues, but the overall process of validating web ontologies has not been formally established yet. As the size and the number of web ontologies continue to grow, the necessity to validate and ensure their consistency and interoperability is becoming increasingly important. This paper presents a validation technique intended to test the consistency of independent ontologies utilized by a common application.Keywords: knowledge engineering, ontological reasoning, ontology validation, semantic web
Procedia PDF Downloads 32213100 Techniques for Seismic Strengthening of Historical Monuments from Diagnosis to Implementation
Authors: Mircan Kaya
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A multi-disciplinary approach is required in any intervention project for historical monuments. Due to the complexity of their geometry, the variable and unpredictable characteristics of original materials used in their creation, heritage structures are peculiar. Their histories are often complex, and they require correct diagnoses to decide on the techniques of intervention. This approach should not only combine technical aspects but also historical research that may help discover phenomena involving structural issues, and acquire a knowledge of the structure on its concept, method of construction, previous interventions, process of damage, and its current state. In addition to the traditional techniques like bed joint reinforcement, the repairing, strengthening and restoration of historical buildings may require several other modern methods which may be described as innovative techniques like pre-stressing and post-tensioning, use of shape memory alloy devices and shock transmission units, shoring, drilling, and the use of stainless steel or titanium. Regardless of the method to be incorporated in the strengthening process, which can be traditional or innovative, it is crucial to recognize that structural strengthening is the process of upgrading the structural system of the existing building with the aim of improving its performance under existing and additional loads like seismic loads. This process is much more complex than dealing with a new construction, owing to the fact that there are several unknown factors associated with the structural system. Material properties, load paths, previous interventions, existing reinforcement are especially important matters to be considered. There are several examples of seismic strengthening with traditional and innovative techniques around the world, which will be discussed in this paper in detail, including their pros and cons. Ultimately, however, the main idea underlying the philosophy of a successful intervention with the most appropriate techniques of strengthening a historic monument should be decided by a proper assessment of the specific needs of the building.Keywords: bed joint reinforcement, historical monuments, post-tensioning, pre-stressing, seismic strengthening, shape memory alloy devices, shock transmitters, tie rods
Procedia PDF Downloads 26513099 Gender Diversity Practices in Talent Management: An Exploratory Study in the Space Industry in Luxembourg
Authors: K. Usanova
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This study contributes to the conceptual and empirical understanding of how gender diversity management (GDM) is integrated into talent management (TM). Following the grounded theory, we interviewed 40 HR managers and talents from the space industry in Luxembourg. We provide a nuanced picture of what attitude on the GDM in TM organizations have, what strategies and practices they conduct, and how they differ from each other. Based on these differences, we developed three types of GDM integration to TM and explained the talents’ view on this issue. To the author's best knowledge, this study is the first empirical investigation of GDM in TM in the space industry that integrates both the TM executives' and TM receivers' views on gender equality in TM.Keywords: gender diversity management, high-technology industry, human resource management, talent management
Procedia PDF Downloads 13313098 Green Roofs and Xeriscape Planting that Contribute to Sustainable Urban Green Space
Authors: Derya Sarı, Banu Karasah
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In the recent years, urban green areas decrease dramatically as a result of increasing industrialization and population growth. At the same time, green spaces provide many ecosystem services such as controls of air pollution, noise reduction, prevents flooding and reduces the stress in the urban areas. Therefore, the plants help to these areas to get more livable and active, and also plants are one of the most significant identity elements in these open spaces. Roof gardens comes significant design comprehension as a result of global warming and also they contribute to cities with regard to ecological, economic, visual and recreational aspects. This study is mainly based on evaluation potential of green roofs and xeriscape planting design approach of Artvin (Turkey) known that generally has a remarkable floristic richness. Artvin is located on a sloping terrain, and the amount of green spaces that can be used is very limited in this city. Therefore, green roofs approach should be evaluated to supply urban green space sustainability. This study shows that it is appropriate about 20 perennial plants for green roofs and xeriscape planting design in Artvin city center. Usage of native plant species would be support to sustainable urban green spaces.Keywords: Artvin, green roofs, urban green spaces, xeriscape planting
Procedia PDF Downloads 47413097 On the Creep of Concrete Structures
Authors: A. Brahma
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Analysis of deferred deformations of concrete under sustained load shows that the creep has a leading role on deferred deformations of concrete structures. Knowledge of the creep characteristics of concrete is a Necessary starting point in the design of structures for crack control. Such knowledge will enable the designer to estimate the probable deformation in pre-stressed concrete or reinforced and the appropriate steps can be taken in design to accommodate this movement. In this study, we propose a prediction model that involves the acting principal parameters on the deferred behaviour of concrete structures. For the estimation of the model parameters Levenberg-Marquardt method has proven very satisfactory. A confrontation between the experimental results and the predictions of models designed shows that it is well suited to describe the evolution of the creep of concrete structures.Keywords: concrete structure, creep, modelling, prediction
Procedia PDF Downloads 29113096 Journal Bearing with Controllable Radial Clearance, Design and Analysis
Authors: Majid Rashidi, Shahrbanoo Farkhondeh Biabnavi
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The hydrodynamic instability phenomenon in a journal bearing may occur by either a reduction in the load carried by journal bearing, by an increase in the journal speed, by change in the lubricant viscosity, or a combination of these factors. The previous research and development work done to overcome the instability issue of journal bearings, operating in hydrodynamic lubricate regime, can be categorized as follows: A) Actively controlling the bearing sleeve by using piezo actuator, b) Inclusion of strategically located and shaped internal grooves within inner surface of the bearing sleeve, c) Actively controlling the bearing sleeve using an electromagnetic actuator, d)Actively and externally pressurizing the lubricant within a journal bearing set, and e)Incorporating tilting pads within the inner surface of the bearing sleeve that assume different equilibrium angular position in response to changes in the bearing design parameter such as speed and load. This work presents an innovative design concept for a 'smart journal bearing' set to operate in a stable hydrodynamic lubrication regime, despite variations in bearing speed, load, and its lubricant viscosity. The proposed bearing design allows adjusting its radial clearance for an attempt to maintain a stable bearing operation under those conditions that may cause instability for a bearing with a fixed radial clearance. The design concept allows adjusting the radial clearance at small increments in the order of 0.00254 mm. This is achieved by axially moving two symmetric conical rigid cavities that are in close contact with the conically shaped outer shell of a sleeve bearing. The proposed work includes a 3D model of the bearing that depicts the structural interactions of the bearing components. The 3D model is employed to conduct finite element Analyses to simulate the mechanical behavior of the bearing from a structural point of view. The concept of controlling of the radial clearance, as presented in this work, is original and has not been proposed and discuss in previous research. A typical journal bearing was analyzed under a set of design parameters, namely r =1.27 cm (journal radius), c = 0.0254 mm (radial clearance), L=1.27 cm (bearing length), w = 445N (bearing load), μ = 0.028 Pascale (lubricant viscosity). A shaft speed as 3600 r.p.m was considered, and the mass supported by the bearing, m, is set to be 4.38kg. The Summerfield Number associated with the above bearing design parameters turn to be, S=0.3. These combinations resulted in stable bearing operation. Subsequently, the speed was postulated to increase from 3600 r.p.mto 7200 r.p.m; the bearing was found to be unstable under the new increased speed. In order to regain stability, the radial clearance was increased from c = 0.0254 mm to0.0358mm. The change in the radial clearance was shown to bring the bearing back to stable an operating condition.Keywords: adjustable clearance, bearing, hydrodynamic, instability, journal
Procedia PDF Downloads 284