Search results for: methane generation model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 19668

Search results for: methane generation model

19398 The Effect of Different Composition of Dairy Cattle Feces Briquette on Moisture and Briquette Density

Authors: Dita Aviana Dewi, Heri Muji, Dian Nur Amalia, Nanung Agus Fitriyanto

Abstract:

Utilization of cow feces as a source of alternative energy can be done with turn it as briquettes. Cow feces generate heat around 4000 Cal/g and the methane gas (CH4) are quite high. Methane gas is one of the essential elements in briquettes which serve as the ignition, so that is resulting briquettes combustible. This study aims to know the difference of the composition of the constituents of briquette moisture content and density. Dairy cattle feces used as the main ingredient with additional material from the waste of the agricultural industry in the form of husk. This study was conducted with three treatments, namely T0= feces 1: husk 1, T1= feces 2: husk 1, and T2= feces 3: husk 1. Each treatment was replicated three times. The experimental design used was Complete Random Design Pattern in line with testing of Dunnet. The observed variables are moisture content and density of the briquettes. Results of this study showed an average moisture content of T0 is 31,17%, T1 is 28,14%, and T2 is 49.95%. The average density of briquettes at T0 is 1,0787 g/cm3, T1 is 1,1448 g/cm3, and T2 is 1,1133 g/cm3. Summary of the study is to take the difference of the composition of the feces and the husk do not have significant effects on moisture content and density of briquettes (p < 0.05).

Keywords: dairy cattle feces, briquette, moisture, density

Procedia PDF Downloads 738
19397 Data Augmentation for Automatic Graphical User Interface Generation Based on Generative Adversarial Network

Authors: Xulu Yao, Moi Hoon Yap, Yanlong Zhang

Abstract:

As a branch of artificial neural network, deep learning is widely used in the field of image recognition, but the lack of its dataset leads to imperfect model learning. By analysing the data scale requirements of deep learning and aiming at the application in GUI generation, it is found that the collection of GUI dataset is a time-consuming and labor-consuming project, which is difficult to meet the needs of current deep learning network. To solve this problem, this paper proposes a semi-supervised deep learning model that relies on the original small-scale datasets to produce a large number of reliable data sets. By combining the cyclic neural network with the generated countermeasure network, the cyclic neural network can learn the sequence relationship and characteristics of data, make the generated countermeasure network generate reasonable data, and then expand the Rico dataset. Relying on the network structure, the characteristics of collected data can be well analysed, and a large number of reasonable data can be generated according to these characteristics. After data processing, a reliable dataset for model training can be formed, which alleviates the problem of dataset shortage in deep learning.

Keywords: GUI, deep learning, GAN, data augmentation

Procedia PDF Downloads 184
19396 Unbalanced Distribution Optimal Power Flow to Minimize Losses with Distributed Photovoltaic Plants

Authors: Malinwo Estone Ayikpa

Abstract:

Electric power systems are likely to operate with minimum losses and voltage meeting international standards. This is made possible generally by control actions provide by automatic voltage regulators, capacitors and transformers with on-load tap changer (OLTC). With the development of photovoltaic (PV) systems technology, their integration on distribution networks has increased over the last years to the extent of replacing the above mentioned techniques. The conventional analysis and simulation tools used for electrical networks are no longer able to take into account control actions necessary for studying distributed PV generation impact. This paper presents an unbalanced optimal power flow (OPF) model that minimizes losses with association of active power generation and reactive power control of single-phase and three-phase PV systems. Reactive power can be generated or absorbed using the available capacity and the adjustable power factor of the inverter. The unbalance OPF is formulated by current balance equations and solved by primal-dual interior point method. Several simulation cases have been carried out varying the size and location of PV systems and the results show a detailed view of the impact of PV distributed generation on distribution systems.

Keywords: distribution system, loss, photovoltaic generation, primal-dual interior point method

Procedia PDF Downloads 332
19395 Rotary Machine Sealing Oscillation Frequencies and Phase Shift Analysis

Authors: Liliia N. Butymova, Vladimir Ya Modorskii

Abstract:

To ensure the gas transmittal GCU's efficient operation, leakages through the labyrinth packings (LP) should be minimized. Leakages can be minimized by decreasing the LP gap, which in turn depends on thermal processes and possible rotor vibrations and is designed to ensure absence of mechanical contact. Vibration mitigation allows to minimize the LP gap. It is advantageous to research influence of processes in the dynamic gas-structure system on LP vibrations. This paper considers influence of rotor vibrations on LP gas dynamics and influence of the latter on the rotor structure within the FSI unidirectional dynamical coupled problem. Dependences of nonstationary parameters of gas-dynamic process in LP on rotor vibrations under various gas speeds and pressures, shaft rotation speeds and vibration amplitudes, and working medium features were studied. The programmed multi-processor ANSYS CFX was chosen as a numerical computation tool. The problem was solved using PNRPU high-capacity computer complex. Deformed shaft vibrations are replaced with an unyielding profile that moves in the fixed annulus "up-and-down" according to set harmonic rule. This solves a nonstationary gas-dynamic problem and determines time dependence of total gas-dynamic force value influencing the shaft. Pressure increase from 0.1 to 10 MPa causes growth of gas-dynamic force oscillation amplitude and frequency. The phase shift angle between gas-dynamic force oscillations and those of shaft displacement decreases from 3π/4 to π/2. Damping constant has maximum value under 1 MPa pressure in the gap. Increase of shaft oscillation frequency from 50 to 150 Hz under P=10 MPa causes growth of gas-dynamic force oscillation amplitude. Damping constant has maximum value at 50 Hz equaling 1.012. Increase of shaft vibration amplitude from 20 to 80 µm under P=10 MPa causes the rise of gas-dynamic force amplitude up to 20 times. Damping constant increases from 0.092 to 0.251. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the minimum gas-dynamic force persistent oscillating amplitude under P=0.1 MPa being observed in methane, and maximum in the air. Frequency remains almost unchanged and the phase shift in the air changes from 3π/4 to π/2. Calculations for various working substances (methane, perfect gas, air at 25 ˚С) prove the maximum gas-dynamic force oscillating amplitude under P=10 MPa being observed in methane, and minimum in the air. Air demonstrates surging. Increase of leakage speed from 0 to 20 m/s through LP under P=0.1 MPa causes the gas-dynamic force oscillating amplitude to decrease by 3 orders and oscillation frequency and the phase shift to increase 2 times and stabilize. Increase of leakage speed from 0 to 20 m/s in LP under P=1 MPa causes gas-dynamic force oscillating amplitude to decrease by almost 4 orders. The phase shift angle increases from π/72 to π/2. Oscillations become persistent. Flow rate proved to influence greatly on pressure oscillations amplitude and a phase shift angle. Work medium influence depends on operation conditions. At pressure growth, vibrations are mostly affected in methane (of working substances list considered), and at pressure decrease, in the air at 25 ˚С.

Keywords: aeroelasticity, labyrinth packings, oscillation phase shift, vibration

Procedia PDF Downloads 296
19394 Business-Intelligence Mining of Large Decentralized Multimedia Datasets with a Distributed Multi-Agent System

Authors: Karima Qayumi, Alex Norta

Abstract:

The rapid generation of high volume and a broad variety of data from the application of new technologies pose challenges for the generation of business-intelligence. Most organizations and business owners need to extract data from multiple sources and apply analytical methods for the purposes of developing their business. Therefore, the recently decentralized data management environment is relying on a distributed computing paradigm. While data are stored in highly distributed systems, the implementation of distributed data-mining techniques is a challenge. The aim of this technique is to gather knowledge from every domain and all the datasets stemming from distributed resources. As agent technologies offer significant contributions for managing the complexity of distributed systems, we consider this for next-generation data-mining processes. To demonstrate agent-based business intelligence operations, we use agent-oriented modeling techniques to develop a new artifact for mining massive datasets.

Keywords: agent-oriented modeling (AOM), business intelligence model (BIM), distributed data mining (DDM), multi-agent system (MAS)

Procedia PDF Downloads 431
19393 Intelligent Agent-Based Model for the 5G mmWave O2I Technology Adoption

Authors: Robert Joseph M. Licup

Abstract:

The deployment of the fifth-generation (5G) mobile system through mmWave frequencies is the new solution in the requirement to provide higher bandwidth readily available for all users. The usage pattern of the mobile users has moved towards either the work from home or online classes set-up because of the pandemic. Previous mobile technologies can no longer meet the high speed, and bandwidth requirement needed, given the drastic shift of transactions to the home. The millimeter-wave (mmWave) underutilized frequency is utilized by the fifth-generation (5G) cellular networks that support multi-gigabit-per-second (Gbps) transmission. However, due to its short wavelengths, high path loss, directivity, blockage sensitivity, and narrow beamwidth are some of the technical challenges that need to be addressed. Different tools, technologies, and scenarios are explored to support network design, accurate channel modeling, implementation, and deployment effectively. However, there is a big challenge on how the consumer will adopt this solution and maximize the benefits offered by the 5G Technology. This research proposes to study the intricacies of technology diffusion, individual attitude, behaviors, and how technology adoption will be attained. The agent based simulation model shaped by the actual applications, technology solution, and related literature was used to arrive at a computational model. The research examines the different attributes, factors, and intricacies that can affect each identified agent towards technology adoption.

Keywords: agent-based model, AnyLogic, 5G O21, 5G mmWave solutions, technology adoption

Procedia PDF Downloads 108
19392 Simple Model of Social Innovation Based on Entrepreneurship Incidence in Mexico

Authors: Vicente Espinola, Luis Torres, Christhian Gonzalez

Abstract:

Entrepreneurship is a topic of current interest in Mexico and the World, which has been fostered through public policies with great impact on its generation. The strategies used in Mexico have not been successful, being motivational strategies aimed at the masses with the intention that someone in the process generates a venture. The strategies used for its development have been "picking of winners" favoring those who have already overcome the initial stages of undertaking without effective support. This situation shows a disarticulation that appears even more in social entrepreneurship; due to this, it is relevant to research on those elements that could develop them and thus integrate a model of entrepreneurship and social innovation for Mexico. Social entrepreneurship should be generating social innovation, which is translated into business models in order to make the benefits reach the population. These models are proposed putting the social impact before the economic impact, without forgetting its sustainability in the medium and long term. In this work, we present a simple model of innovation and social entrepreneurship for Guanajuato, Mexico. This algorithm was based on how social innovation could be generated in a systemic way for Mexico through different institutions that promote innovation. In this case, the technological parks of the state of Guanajuato were studied because these are considered one of the areas of Mexico where its main objectives are to make technology transfer to companies but overlooking the social sector and entrepreneurs. An experimental design of n = 60 was carried out with potential entrepreneurs to identify their perception of the social approach that the enterprises should have, the skills they consider required to create a venture, as well as their interest in generating ventures that solve social problems. This experiment had a 2K design, the value of k = 3 and the computational simulation was performed in R statistical language. A simple model of interconnected variables is proposed, which allows us to identify where it is necessary to increase efforts for the generation of social enterprises. The 96.67% of potential entrepreneurs expressed interest in ventures that solve social problems. In the analysis of the variables interaction, it was identified that the isolated development of entrepreneurial skills would only replicate the generation of traditional ventures. The variable of social approach presented positive interactions, which may influence the generation of social entrepreneurship if this variable was strengthened and permeated in the processes of training and development of entrepreneurs. In the future, it will be necessary to analyze the institutional actors that are present in the social entrepreneurship ecosystem, in order to analyze the interaction necessary to strengt the innovation and social entrepreneurship ecosystem.

Keywords: social innovation, model, entrepreneurship, technological parks

Procedia PDF Downloads 273
19391 Analysis of the Temperature Dependence of Local Avalanche Compact Model for Bipolar Transistors

Authors: Robert Setekera, Ramses van der Toorn

Abstract:

We present an extensive analysis of the temperature dependence of the local avalanche model used in most of the modern compact models for bipolar transistors. This local avalanche model uses the Chynoweth's empirical law for ionization coefficient to define the generation of the avalanche current in terms of the local electric field. We carry out the model analysis using DC-measurements taken on both Si and advanced SiGe bipolar transistors. For the advanced industrial SiGe-HBTs, we consider both high-speed and high-power devices (both NPN and PNP transistors). The limitations of the local avalanche model in modeling the temperature dependence of the avalanche current mostly in the weak avalanche region are demonstrated. In addition, the model avalanche parameters are analyzed to see if they are in agreement with semiconductor device physics.

Keywords: avalanche multiplication, avalanche current, bipolar transistors, compact modeling, electric field, impact ionization, local avalanche

Procedia PDF Downloads 622
19390 Influence of Disintegration of Sida hermaphrodita Silage on Methane Fermentation Efficiency

Authors: Marcin Zielinski, Marcin Debowski, Paulina Rusanowska, Magda Dudek

Abstract:

As a result of sonification, the destruction of complex biomass structures results in an increase in the biogas yield from the conditioned material. First, the amount of organic matter released into the solution due to disintegration was determined. This parameter was determined by changes in the carbon content in liquid phase of the conditioned substrate. The amount of carbon in the liquid phase increased with the prolongation of the sonication time to 16 min. Further increase in the duration of sonication did not cause a statistically significant increase in the amount of organic carbon in the liquid phase. The disintegrated material was then used for respirometric measurements for determination of the impact of the conditioning process used on methane fermentation effectiveness. The relationship between the amount of energy introduced into the lignocellulosic substrate and the amount of biogas produced has been demonstrated. Statistically significant increase in the amount of biogas was observed until sonication of 16 min. Further increase in energy in the conditioning process did not significantly increase the production of biogas from the treated substrate. The biogas production from the conditioned substrate was 17% higher than from the reference biomass at that time. The ultrasonic disintegration method did not significantly affect the observed biogas composition. In all series, the methane content in the produced biogas from the conditioned substrate was similar to that obtained with the raw substrate sample (51.1%). Another method of substrate conditioning was hydrothermal depolymerization. This method consists in application of increased temperature and pressure to substrate. These phenomena destroy the structure of the processed material, the release of organic compounds to the solution, which should lead to increase the amount of produced biogas from such treated biomass. The hydrothermal depolymerization was conducted using an innovative microwave heating method. Control measurements were performed using conventional heating. The obtained results indicate the relationship between depolymerization temperature and the amount of biogas. Statistically significant value of the biogas production coefficients increased as the depolymerization temperature increased to 150°C. Further raising the depolymerization temperature to 180°C did not significantly increase the amount of produced biogas in the respirometric tests. As a result of the hydrothermal depolymerization obtained using microwave at 150°C for 20 min, the rate of biogas production from the Sida silage was 780 L/kg VS, which accounted for nearly 50% increase compared to 370 L/kg VS obtained from the same silage but not depolymerised. The study showed that by microwave heating it is possible to effectively depolymerized substrate. Significant differences occurred especially in the temperature range of 130-150ºC. The pre-treatment of Sida hermaphrodita silage (biogas substrate) did not significantly affect the quality of the biogas produced. The methane concentration was about 51.5% on average. The study was carried out in the framework of the project under program BIOSTRATEG funded by the National Centre for Research and Development No. 1/270745/2/NCBR/2015 'Dietary, power, and economic potential of Sida hermaphrodita cultivation on fallow land'.

Keywords: disintegration, biogas, methane fermentation, Virginia fanpetals, biomass

Procedia PDF Downloads 309
19389 Internal Methane Dry Reforming Kinetic Models in Solid Oxide Fuel Cells

Authors: Saeed Moarrefi, Shou-Han Zhou, Liyuan Fan

Abstract:

Coupling with solid oxide fuel cells, methane dry reforming is a promising pathway for energy production while mitigating carbon emissions. However, the influence of carbon dioxide and electrochemical reactions on the internal dry reforming reaction within the fuel cells remains debatable, requiring accurate kinetic models to describe the internal reforming behaviors. We employed the Power-Law and Langmuir Hinshelwood–Hougen Watson models in an electrolyte-supported solid oxide fuel cell with a NiO-GDC-YSZ anode. The current density used in this study ranges from 0 to 1000 A/m2 at 973 K to 1173 K to estimate various kinetic parameters. The influence of the electrochemical reactions on the adsorption terms, the equilibrium of the reactions, the activation energy, the pre-exponential factor of the rate constant, and the adsorption equilibrium constant were studied. This study provides essential parameters for future simulations and highlights the need for a more detailed examination of reforming kinetic models.

Keywords: dry reforming kinetics, Langmuir Hinshelwood–Hougen Watson, power-law, SOFC

Procedia PDF Downloads 22
19388 Modeling of Virtual Power Plant

Authors: Muhammad Fanseem E. M., Rama Satya Satish Kumar, Indrajeet Bhausaheb Bhavar, Deepak M.

Abstract:

Keeping the right balance of electricity between the supply and demand sides of the grid is one of the most important objectives of electrical grid operation. Power generation and demand forecasting are the core of power management and generation scheduling. Large, centralized producing units were used in the construction of conventional power systems in the past. A certain level of balance was possible since the generation kept up with the power demand. However, integrating renewable energy sources into power networks has proven to be a difficult challenge due to its intermittent nature. The power imbalance caused by rising demands and peak loads is negatively affecting power quality and dependability. Demand side management and demand response were one of the solutions, keeping generation the same but altering or rescheduling or shedding completely the load or demand. However, shedding the load or rescheduling is not an efficient way. There comes the significance of virtual power plants. The virtual power plant integrates distributed generation, dispatchable load, and distributed energy storage organically by using complementing control approaches and communication technologies. This would eventually increase the utilization rate and financial advantages of distributed energy resources. Most of the writing on virtual power plant models ignored technical limitations, and modeling was done in favor of a financial or commercial viewpoint. Therefore, this paper aims to address the modeling intricacies of VPPs and their technical limitations, shedding light on a holistic understanding of this innovative power management approach.

Keywords: cost optimization, distributed energy resources, dynamic modeling, model quality tests, power system modeling

Procedia PDF Downloads 62
19387 Numerical Simulation of a Point Absorber Wave Energy Converter Using OpenFOAM in Indian Scenario

Authors: Pooja Verma, Sumana Ghosh

Abstract:

There is a growing need for alternative way of power generation worldwide. The reason can be attributed to limited resources of fossil fuels, environmental pollution, increasing cost of conventional fuels, and lower efficiency of conversion of energy in existing systems. In this context, one of the potential alternatives for power generation is wave energy. However, it is difficult to estimate the amount of electrical energy generation in an irregular sea condition by experiment and or analytical methods. Therefore in this work, a numerical wave tank is developed using the computational fluid dynamics software Open FOAM. In this software a specific utility known as waves2Foam utility is being used to carry out the simulation work. The computational domain is a tank of dimension: 5m*1.5m*1m with a floating object of dimension: 0.5m*0.2m*0.2m. Regular waves are generated at the inlet of the wave tank according to Stokes second order theory. The main objective of the present study is to validate the numerical model against existing experimental data. It shows a good matching with the existing experimental data of floater displacement. Later the model is exploited to estimate energy extraction due to the movement of such a point absorber in real sea conditions. Scale down the wave properties like wave height, wave length, etc. are used as input parameters. Seasonal variations are also considered.

Keywords: OpenFOAM, numerical wave tank, regular waves, floating object, point absorber

Procedia PDF Downloads 352
19386 Study on the Integration Schemes and Performance Comparisons of Different Integrated Solar Combined Cycle-Direct Steam Generation Systems

Authors: Liqiang Duan, Ma Jingkai, Lv Zhipeng, Haifan Cai

Abstract:

The integrated solar combined cycle (ISCC) system has a series of advantages such as increasing the system power generation, reducing the cost of solar power generation, less pollutant and CO2 emission. In this paper, the parabolic trough collectors with direct steam generation (DSG) technology are considered to replace the heat load of heating surfaces in heat regenerator steam generation (HRSG) of a conventional natural gas combined cycle (NGCC) system containing a PG9351FA gas turbine and a triple pressure HRSG with reheat. The detailed model of the NGCC system is built in ASPEN PLUS software and the parabolic trough collectors with DSG technology is modeled in EBSILON software. ISCC-DSG systems with the replacement of single, two, three and four heating surfaces are studied in this paper. Results show that: (1) the ISCC-DSG systems with the replacement heat load of HPB, HPB+LPE, HPE2+HPB+HPS, HPE1+HPE2+ HPB+HPS are the best integration schemes when single, two, three and four stages of heating surfaces are partly replaced by the parabolic trough solar energy collectors with DSG technology. (2) Both the changes of feed water flow and the heat load of the heating surfaces in ISCC-DSG systems with the replacement of multi-stage heating surfaces are smaller than those in ISCC-DSG systems with the replacement of single heating surface. (3) ISCC-DSG systems with the replacement of HPB+LPE heating surfaces can increase the solar power output significantly. (4) The ISCC-DSG systems with the replacement of HPB heating surfaces has the highest solar-thermal-to-electricity efficiency (47.45%) and the solar radiation energy-to-electricity efficiency (30.37%), as well as the highest exergy efficiency of solar field (33.61%).

Keywords: HRSG, integration scheme, parabolic trough collectors with DSG technology, solar power generation

Procedia PDF Downloads 253
19385 The Influence of Physical Activity and Health Literacy on Depression Level of First and Second Turkish Generation Living in Germany

Authors: Ceren Akyüz, Ingo Froboese

Abstract:

Health literacy has gained importance with the further spread of the coronavirus disease (COVID-19) worldwide and has been associated with health status in various chronic diseases. Many studies indicate that mental health can be improved by low- or moderate-intensity activity, and several studies have been proposed to explain the relationship between physical activity and mental health. The aim of the present study is to investigate the levels of physical activity, health literacy, and depression in first- and- second generation Turkish people in Germany. The research consists of 434 participants (255 females, 179 males; age 38.09 ± 13.73). 40.8 % of participants are married, and 59.2 % of participants are single. Education levels are mostly at university level (54.8 %), and graduate level is 18.9 %. While 24.9 % of the participants are second generation, 75.1 % of participants are first generation. All analyses were stratified on gender, marital status, education, generation and income status, and five age categories: 18–30, 31–40, 41–50, 51–60, and 61–79, which were defined to account for age-specific trends while maintaining sufficient cell size for statistical analysis. A correlation of depression with physical activity and health literacy levels between first- and- second generation Turks in Germany was evaluated in order to find out whether there are significant differences between the two populations and demographic variables (gender, marital status, education, generation, income status) with carrying out questionnaires which are European Health Literacy Survey Questionnaire (HLS-EU-Q47), International Physical Activity Questionnaire ( IPAQ) and the Patient Health Questionnaire-9 (PHQ-9).

Keywords: health literacy, turks in germany, migrants, depression, physical activity

Procedia PDF Downloads 82
19384 Comparison of Entropy Coefficient and Internal Resistance of Two (Used and Fresh) Cylindrical Commercial Lithium-Ion Battery (NCR18650) with Different Capacities

Authors: Sara Kamalisiahroudi, Zhang Jianbo, Bin Wu, Jun Huang, Laisuo Su

Abstract:

The temperature rising within a battery cell depends on the level of heat generation, the thermal properties and the heat transfer around the cell. The rising of temperature is a serious problem of Lithium-Ion batteries and the internal resistance of battery is the main reason for this heating up, so the heat generation rate of the batteries is an important investigating factor in battery pack design. The delivered power of a battery is directly related to its capacity, decreases in the battery capacity means the growth of the Solid Electrolyte Interface (SEI) layer which is because of the deposits of lithium from the electrolyte to form SEI layer that increases the internal resistance of the battery. In this study two identical cylindrical Lithium-Ion (NCR18650)batteries from the same company with noticeable different in capacity (a fresh and a used battery) were compared for more focusing on their heat generation parameters (entropy coefficient and internal resistance) according to Brandi model, by utilizing potentiometric method for entropy coefficient and EIS method for internal resistance measurement. The results clarify the effect of capacity difference on cell electrical (R) and thermal (dU/dT) parameters. It can be very noticeable in battery pack design for its Safety.

Keywords: heat generation, Solid Electrolyte Interface (SEI), potentiometric method, entropy coefficient

Procedia PDF Downloads 473
19383 Decarbonising Urban Building Heating: A Case Study on the Benefits and Challenges of Fifth-Generation District Heating Networks

Authors: Mazarine Roquet, Pierre Dewallef

Abstract:

The building sector, both residential and tertiary, accounts for a significant share of greenhouse gas emissions. In Belgium, partly due to poor insulation of the building stock, but certainly because of the massive use of fossil fuels for heating buildings, this share reaches almost 30%. To reduce carbon emissions from urban building heating, district heating networks emerge as a promising solution as they offer various assets such as improving the load factor, integrating combined heat and power systems, and enabling energy source diversification, including renewable sources and waste heat recovery. However, mainly for sake of simple operation, most existing district heating networks still operate at high or medium temperatures ranging between 120°C and 60°C (the socalled second and third-generations district heating networks). Although these district heating networks offer energy savings in comparison with individual boilers, such temperature levels generally require the use of fossil fuels (mainly natural gas) with combined heat and power. The fourth-generation district heating networks improve the transport and energy conversion efficiency by decreasing the operating temperature between 50°C and 30°C. Yet, to decarbonise the building heating one must increase the waste heat recovery and use mainly wind, solar or geothermal sources for the remaining heat supply. Fifth-generation networks operating between 35°C and 15°C offer the possibility to decrease even more the transport losses, to increase the share of waste heat recovery and to use electricity from renewable resources through the use of heat pumps to generate low temperature heat. The main objective of this contribution is to exhibit on a real-life test case the benefits of replacing an existing third-generation network by a fifth-generation one and to decarbonise the heat supply of the building stock. The second objective of the study is to highlight the difficulties resulting from the use of a fifth-generation, low-temperature, district heating network. To do so, a simulation model of the district heating network including its regulation is implemented in the modelling language Modelica. This model is applied to the test case of the heating network on the University of Liège's Sart Tilman campus, consisting of around sixty buildings. This model is validated with monitoring data and then adapted for low-temperature networks. A comparison of primary energy consumptions as well as CO2 emissions is done between the two cases to underline the benefits in term of energy independency and GHG emissions. To highlight the complexity of operating a lowtemperature network, the difficulty of adapting the mass flow rate to the heat demand is considered. This shows the difficult balance between the thermal comfort and the electrical consumption of the circulation pumps. Several control strategies are considered and compared to the global energy savings. The developed model can be used to assess the potential for energy and CO2 emissions savings retrofitting an existing network or when designing a new one.

Keywords: building simulation, fifth-generation district heating network, low-temperature district heating network, urban building heating

Procedia PDF Downloads 83
19382 A Model-Driven Approach of User Interface for MVP Rich Internet Application

Authors: Sarra Roubi, Mohammed Erramdani, Samir Mbarki

Abstract:

This paper presents an approach for the model-driven generating of Rich Internet Application (RIA) focusing on the graphical aspect. We used well known Model-Driven Engineering (MDE) frameworks and technologies, such as Eclipse Modeling Framework (EMF), Graphical Modeling Framework (GMF), Query View Transformation (QVTo) and Acceleo to enable the design and the code automatic generation of the RIA. During the development of the approach, we focused on the graphical aspect of the application in terms of interfaces while opting for the Model View Presenter pattern that is designed for graphics interfaces. The paper describes the process followed to define the approach, the supporting tool and presents the results from a case study.

Keywords: metamodel, model-driven engineering, MVP, rich internet application, transformation, user interface

Procedia PDF Downloads 353
19381 Exploring the Travel Preferences of Generation Z: A Look into the Next Generation of Tourists

Authors: M. Panidou, F. Kilipiris, E. Christou, K. Alexandris

Abstract:

This study focuses on Generation Z, the next generation of tourists born between 1996 and 2012. Given their significant population size, Generation Z is expected to have a substantial impact on the travel and tourism sector. Therefore, understanding their travel preferences is crucial for businesses in the hospitality and tourism industry. By examining their travel preferences, this research aims to identify the unique characteristics and motivations of this generation when it comes to travel. This study used a quantitative method, and primary data was collected through a survey (online questionnaire), while secondary data was gathered from academic literature, industry reports, and online sources to provide a comprehensive analysis of the topic. The sample of the study was 100 Greek individuals aged between 18-26 years old. The data was analyzed with the support of SPSS software. The findings of the research indicated that technology, sustainability, and budget-friendly options are essential components for attracting and retaining Generation Z tourists. These preferences highlight the importance of incorporating innovative technologies, promoting sustainable practices, and offering affordable travel options to effectively engage this market niche. This research contributes to the field of hospitality and tourism businesses by providing valuable insights into the travel preferences of Generation Z. By understanding their distinct features and preferences; businesses can tailor their strategies and marketing efforts to effectively engage and retain this market segment. Considering the limitations of the sample size, future studies could aim for a larger and more diverse sample to enhance the generalizability of the findings.

Keywords: gen Z, technology, travel preferences, sustainability

Procedia PDF Downloads 86
19380 A Generic Approach to Reuse Unified Modeling Language Components Following an Agile Process

Authors: Rim Bouhaouel, Naoufel Kraïem, Zuhoor Al Khanjari

Abstract:

Unified Modeling Language (UML) is considered as one of the widespread modeling language standardized by the Object Management Group (OMG). Therefore, the model driving engineering (MDE) community attempts to provide reuse of UML diagrams, and do not construct it from scratch. The UML model appears according to a specific software development process. The existing method generation models focused on the different techniques of transformation without considering the development process. Our work aims to construct an UML component from fragments of UML diagram basing on an agile method. We define UML fragment as a portion of a UML diagram, which express a business target. To guide the generation of fragments of UML models using an agile process, we need a flexible approach, which adapts to the agile changes and covers all its activities. We use the software product line (SPL) to derive a fragment of process agile method. This paper explains our approach, named RECUP, to generate UML fragments following an agile process, and overviews the different aspects. In this paper, we present the approach and we define the different phases and artifacts.

Keywords: UML, component, fragment, agile, SPL

Procedia PDF Downloads 397
19379 Evaluating the effects of Gas Injection on Enhanced Gas-Condensate Recovery and Reservoir Pressure Maintenance

Authors: F. S. Alavi, D. Mowla, F. Esmaeilzadeh

Abstract:

In this paper, the Eclipse 300 simulator was used to perform compositional modeling of gas injection process for enhanced condensate recovery of a real gas condensate well in south of Iran here referred to as SA4. Some experimental data were used to tune the Peng-Robinson equation of state for this case. Different scenarios of gas injection at current reservoir pressure and at abandonment reservoir pressure had been considered with different gas compositions. Methane, carbon dioxide, nitrogen and two other gases with specified compositions were considered as potential gases for injection. According to the obtained results, nitrogen leads to highest pressure maintenance in the reservoir but methane results in highest condensate recovery among the selected injection gases. At low injection rates, condensate recovery percent is strongly affected by gas injection rate but this dependency shifts to zero at high injection rates. Condensate recovery is higher in all cases of injection at current reservoir pressure than injection at abandonment pressure. Using a constant injection rate, increasing the production well bottom hole pressure results in increasing the condensate recovery percent and time of gas breakthrough.

Keywords: gas-condensate reservoir, case-study, compositional modelling, enhanced condensate recovery, gas injection

Procedia PDF Downloads 194
19378 Orange Leaves and Rice Straw on Methane Emission and Milk Production in Murciano-Granadina Dairy Goat Diet

Authors: Tamara Romero, Manuel Romero-Huelva, Jose V. Segarra, Jose Castro, Carlos Fernandez

Abstract:

Many foods resulting from processing and manufacturing end up as waste, most of which is burned, dumped into landfills or used as compost, which leads to wasted resources, and environmental problems due to unsuitable disposal. Using residues of the crop and food processing industries to feed livestock has the advantage to obviating the need for costly waste management programs. The main residue generated in citrus cultivations and rice crop are pruning waste and rice straw, respectively. Within Spain, the Valencian Community is one of the world's oldest citrus and rice production areas. The objective of this experiment found out the effects of including orange leaves and rice straw as ingredients in the concentrate diets of goats, on milk production and methane (CH₄) emissions. Ten Murciano-Granadina dairy goats (45 kg of body weight, on average) in mid-lactation were selected in a crossover design experiment, where each goat received two treatments in 2 periods. Both groups were fed with 1.7 kg pelleted mixed ration; one group (n= 5) was a control (C) and the other group (n= 5) used orange leaves and rice straw (OR). The forage was alfalfa hay, and it was the same for the two groups (1 kg of alfalfa was offered by goat and day). The diets employed to achieve the requirements during lactation period for caprine livestock. The goats were allocated to individual metabolism cages. After 14 days of adaptation, feed intake and milk yield were recorded daily over a 5 days period. Physico-chemical parameters and somatic cell count in milk samples were determined. Then, gas exchange measurements were recorded individually by an open-circuit indirect calorimetry system using a head box. The data were analyzed by mixed model with diet and digestibility as fixed effect and goat as random effect. No differences were found for dry matter intake (2.23 kg/d, on average). Higher milk yield was found for C diet than OR (2.3 vs. 2.1 kg/goat and day, respectively) and, greater milk fat content was observed for OR than C (6.5 vs. 5.5%, respectively). The cheese extract was also greater in OR than C (10.7 vs. 9.6%). Goats fed OR diet produced significantly fewer CH₄ emissions than C diet (27 vs. 30 g/d, respectively). These preliminary results (LIFE Project LOWCARBON FEED LIFE/CCM/ES/000088) suggested that the use of these waste by-products was effective in reducing CH₄ emission without detrimental effect on milk yield.

Keywords: agricultural waste, goat, milk production, methane emission

Procedia PDF Downloads 148
19377 Proactive WPA/WPA2 Security Using DD-WRT Firmware

Authors: Mustafa Kamoona, Mohamed El-Sharkawy

Abstract:

Although the latest Wireless Local Area Network technology Wi-Fi 802.11i standard addresses many of the security weaknesses of the antecedent Wired Equivalent Privacy (WEP) protocol, there are still scenarios where the network security are still vulnerable. The first security model that 802.11i offers is the Personal model which is very cheap and simple to install and maintain, yet it uses a Pre Shared Key (PSK) and thus has a low to medium security level. The second model that 802.11i provide is the Enterprise model which is highly secured but much more expensive and difficult to install/maintain and requires the installation and maintenance of an authentication server that will handle the authentication and key management for the wireless network. A central issue with the personal model is that the PSK needs to be shared with all the devices that are connected to the specific Wi-Fi network. This pre-shared key, unless changed regularly, can be cracked using offline dictionary attacks within a matter of hours. The key is burdensome to change in all the connected devices manually unless there is some kind of algorithm that coordinate this PSK update. The key idea of this paper is to propose a new algorithm that proactively and effectively coordinates the pre-shared key generation, management, and distribution in the cheap WPA/WPA2 personal security model using only a DD-WRT router.

Keywords: Wi-Fi, WPS, TLS, DD-WRT

Procedia PDF Downloads 233
19376 The Climate Impact Due to Clouds and Selected Greenhouse Gases by Short Wave Upwelling Radiative Flux within Spectral Range of Space-Orbiting Argus1000 Micro-Spectrometer

Authors: Rehan Siddiqui, Brendan Quine

Abstract:

The Radiance Enhancement (RE) and integrated absorption technique is applied to develop a synthetic model to determine the enhancement in radiance due to cloud scene and Shortwave upwelling Radiances (SHupR) by O2, H2O, CO2 and CH4. This new model is used to estimate the magnitude variation for RE and SHupR over spectral range of 900 nm to 1700 nm by varying surface altitude, mixing ratios and surface reflectivity. In this work, we employ satellite real observation of space orbiting Argus 1000 especially for O2, H2O, CO2 and CH4 together with synthetic model by using line by line GENSPECT radiative transfer model. All the radiative transfer simulations have been performed by varying over a different range of percentages of water vapor contents and carbon dioxide with the fixed concentration oxygen and methane. We calculate and compare both the synthetic and real measured observed data set of different week per pass of Argus flight. Results are found to be comparable for both approaches, after allowing for the differences with the real and synthetic technique. The methodology based on RE and SHupR of the space spectral data can be promising for the instant and reliable classification of the cloud scenes.

Keywords: radiance enhancement, radiative transfer, shortwave upwelling radiative flux, cloud reflectivity, greenhouse gases

Procedia PDF Downloads 336
19375 A New Fuzzy Fractional Order Model of Transmission of Covid-19 With Quarantine Class

Authors: Asma Hanif, A. I. K. Butt, Shabir Ahmad, Rahim Ud Din, Mustafa Inc

Abstract:

This paper is devoted to a study of the fuzzy fractional mathematical model reviewing the transmission dynamics of the infectious disease Covid-19. The proposed dynamical model consists of susceptible, exposed, symptomatic, asymptomatic, quarantine, hospitalized and recovered compartments. In this study, we deal with the fuzzy fractional model defined in Caputo’s sense. We show the positivity of state variables that all the state variables that represent different compartments of the model are positive. Using Gronwall inequality, we show that the solution of the model is bounded. Using the notion of the next-generation matrix, we find the basic reproduction number of the model. We demonstrate the local and global stability of the equilibrium point by using the concept of Castillo-Chavez and Lyapunov theory with the Lasalle invariant principle, respectively. We present the results that reveal the existence and uniqueness of the solution of the considered model through the fixed point theorem of Schauder and Banach. Using the fuzzy hybrid Laplace method, we acquire the approximate solution of the proposed model. The results are graphically presented via MATLAB-17.

Keywords: Caputo fractional derivative, existence and uniqueness, gronwall inequality, Lyapunov theory

Procedia PDF Downloads 105
19374 An Integrated Modular Approach Based Simulation of Cold Heavy Oil Production

Authors: Hamidreza Sahaleh

Abstract:

In this paper, the authors display an incorporated secluded way to deal with quantitatively foresee volumetric sand generation and improved oil recuperation. This model is in light of blend hypothesis with erosion mechanics, in which multiphase hydrodynamics and geo-mechanics are coupled in a predictable way by means of principal unknowns, for example, saturation, pressure, porosity, and formation displacements. Foamy oil is demonstrated as a scattering of gas bubbles caught in the oil, where these gas air bubbles keep up a higher repository weight. A secluded methodology is then received to adequately exploit the current propelled standard supply and stress-strain codes. The model is actualized into three coordinated computational modules, i.e. erosion module, store module, and geo-mechanics module. The stress, stream and erosion mathematical statements are understood independently for every time addition, and the coupling terms (porosity, penetrability, plastic shear strain, and so on) are gone among them and iterated until certain union is accomplished on a period step premise. The framework is capable regarding its abilities, yet practical in terms of computer requirements and maintenance. Numerical results of field studies are displayed to show the capacities of the model. The impacts of foamy oil stream and sand generation are additionally inspected to exhibit their effect on the upgraded hydrocarbon recuperation.

Keywords: oil recuperation, erosion mechanics, foamy oil, erosion module.

Procedia PDF Downloads 268
19373 From Modeling of Data Structures towards Automatic Programs Generating

Authors: Valentin P. Velikov

Abstract:

Automatic program generation saves time, human resources, and allows receiving syntactically clear and logically correct modules. The 4-th generation programming languages are related to drawing the data and the processes of the subject area, as well as, to obtain a frame of the respective information system. The application can be separated in interface and business logic. That means, for an interactive generation of the needed system to be used an already existing toolkit or to be created a new one.

Keywords: computer science, graphical user interface, user dialog interface, dialog frames, data modeling, subject area modeling

Procedia PDF Downloads 305
19372 Third Generation Greek Identities

Authors: Panayiota Romios

Abstract:

Greek diaspora communities with their specific cultural identity are found throughout the world and exist on a continuum of redefinition and renewal. This paper investigates Greek migration to Australia, followed by a discussion of findings from a qualitative study of sixteen third generation Greek Australians conducted by the author in Melbourne, Australia, in 2021. The Greek-born population in Australia increased from 15,000 in 1930 to well over 300,000 by 1970. Over the next decades, first-generation Greek migrants successfully sustain a Greek identity that promotes difference within Australia. Their Australian-born children, while constructing Greek Australian hybrid identities through an encounter with difference, integrate successfully into Australian society and maintain strong connections to Greece. This study explores the third generation Greek Australian identities, the children of the second generation, and their having horizontal and vertical orientations, where the former designates transgression of borders and space and the latter is connected to the movement across time. This approach is particularly interesting in the context of Greek Australian migrant and diasporic experience as hybridity understood as movement and translocation can offer new perspectives on migrant identities in multi-and transcultural worlds.

Keywords: diaspora, migration, hybridity, ethnicty

Procedia PDF Downloads 147
19371 Flame Propagation Velocity of Selected Gas Mixtures Depending on the Temperature

Authors: Kaczmarzyk Piotr, Anna Dziechciarz, Wojciech Klapsa

Abstract:

The purpose of this paper is demonstration the test results of research influence of temperature on the velocity of flame propagation using gas and air mixtures for selected gas mixtures. The research was conducted on the test apparatus in the form of duct 2 m long. The test apparatus was funded from the project: “Development of methods to neutralize threats of explosion for determined tanks contained technical gases, including alternative sources of supply in the fire environment, taking into account needs of rescuers” number: DOB-BIO6/02/50/2014. The Project is funded by The National Centre for Research and Development. This paper presents the results of measurement of rate of pressure rise and rate in flame propagation, using test apparatus for mixtures air and methane or air and propane. This paper presents the results performed using the test apparatus in the form of duct measuring the rate of flame and overpressure wave. Studies were performed using three gas mixtures with different concentrations: Methane (3% to 8% vol), Propane (3% to 6% vol). As regard to the above concentrations, tests were carried out at temperatures 20 and 30 ̊C. The gas mixture was supplied to the inside of the duct by the partial pressure molecules. Data acquisition was made using 5 dynamic pressure transducers and 5 ionization probes, arranged along of the duct. Temperature conditions changes were performed using heater which was mounted on the duct’s bottom. During the tests, following parameters were recorded: maximum explosion pressure, maximum pressure recorded by sensors and voltage recorded by ionization probes. Performed tests, for flammable gas and air mixtures, indicate that temperature changes have an influence on overpressure velocity. It should be noted, that temperature changes do not have a major impact on the flame front velocity. In the case of propane and air mixtures (temperature 30 ̊C) was observed DDT (Deflagration to Detonation) phenomena. The velocity increased from 2 to 20 m/s. This kind of explosion could turn into a detonation, but the duct length is too short (2 m).

Keywords: flame propagation, flame propagation velocity, explosion, propane, methane

Procedia PDF Downloads 226
19370 Stability Analysis of a Human-Mosquito Model of Malaria with Infective Immigrants

Authors: Nisha Budhwar, Sunita Daniel

Abstract:

In this paper, we analyse the stability of the SEIR model of malaria with infective immigrants which was recently formulated by the authors. The model consists of an SEIR model for the human population and SI Model for the mosquitoes. Susceptible humans become infected after they are bitten by infectious mosquitoes and move on to the Exposed, Infected and Recovered classes respectively. The susceptible mosquito becomes infected after biting an infected person and remains infected till death. We calculate the reproduction number R0 using the next generation method and then discuss about the stability of the equilibrium points. We use the Lyapunov function to show the global stability of the equilibrium points.

Keywords: equilibrium points, exposed, global stability, infective immigrants, Lyapunov function, recovered, reproduction number, susceptible

Procedia PDF Downloads 364
19369 Feasibility Study of Utilization and Development of Wind Energy for Electricity Generation in Panjang Island, Serang, Banten, West Java

Authors: Aryo Bayu Tejokusumo, Ivan Hidayat, C. Steffany Yoland

Abstract:

Wind velocity in Panjang Island, Serang, Banten, West Java, measured 10 m above sea level, is about 8 m/s. This wind velocity is potential for electricity generation using wind power. Using ten of Alstom-Haliade 150-6 W turbines, the placement of wind turbines has 7D for vertical distance and 4D for horizontal distance. Installation of the turbines is 100 m above sea level which is produces 98.64 MW per hour. This wind power generation has ecology impacts (the deaths of birds and bats and land exemption) and human impacts (aesthetics, human’s health, and potential disruption of electromagnetics interference), but it could be neglected totally, because of the position of the wind farm. The investment spent 73,819,710.00 IDR. Payback period is 2.23 years, and rate of return is 45.24%. This electricity generation using wind power in Panjang Island is suitable to install despite the high cost of investment since the profit is also high.

Keywords: wind turbine, Panjang island, renewable energy, Indonesia, offshore, power generation

Procedia PDF Downloads 662