Search results for: share of electricity generation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5100

Search results for: share of electricity generation

4830 Numerical Prediction of Entropy Generation in Heat Exchangers

Authors: Nadia Allouache

Abstract:

The concept of second law is assumed to be important to optimize the energy losses in heat exchangers. The present study is devoted to the numerical prediction of entropy generation due to heat transfer and friction in a double tube heat exchanger partly or fully filled with a porous medium. The goal of this work is to find the optimal conditions that allow minimizing entropy generation. For this purpose, numerical modeling based on the control volume method is used to describe the flow and heat transfer phenomena in the fluid and the porous medium. Effects of the porous layer thickness, its permeability, and the effective thermal conductivity have been investigated. Unexpectedly, the fully porous heat exchanger yields a lower entropy generation than the partly porous case or the fluid case even if the friction increases the entropy generation.

Keywords: heat exchangers, porous medium, second law approach, turbulent flow

Procedia PDF Downloads 264
4829 Optimization of Line Loss Minimization Using Distributed Generation

Authors: S. Sambath, P. Palanivel

Abstract:

Research conducted in the last few decades has proven that an inclusion of Distributed Genaration (DG) into distribution systems considerably lowers the level of power losses and the power quality improved. Moreover, the choice of DG is even more attractive since it provides not only benefits in power loss minimisation, but also a wide range of other advantages including environment, economic, power qualities and technical issues. This paper is an intent to quantify and analyse the impact of distributed generation (DG) in Tamil Nadu, India to examine what the benefits of decentralized generation would be for meeting rural loads. We used load flow analysis to simulate and quantify the loss reduction and power quality enhancement by having decentralized generation available line conditions for actual rural feeders in Tamil Nadu, India. Reactive and voltage profile was considered. This helps utilities to better plan their system in rural areas to meet dispersed loads, while optimizing the renewable and decentralised generation sources.

Keywords: distributed generation, distribution system, load flow analysis, optimal location, power quality

Procedia PDF Downloads 374
4828 Two Steady States and Two Movement Patterns under the Balanced Budget Rule: An Economy with Divisible Labor

Authors: Fujio Takata

Abstract:

When governments levy taxes on labor income on the basis of a balanced budget rule, two steady states in an economy exist, of which one can cause two movement patterns, namely, indeterminacy paths and a saddle path. However, in this paper, we assume an economy with divisible labor, in which labor adjustment is made by an intensive margin. We demonstrate that there indeed exist the two paths in the economy and that there exists a critical condition dividing them. This is proved by establishing the relationship between a finite elasticity of labor with regard to real wages and the share of capital in output. Consequently, we deduce the existence of an upper limit in the share of capital in output for indeterminacy to occur. The largest possible value of that share is less than 0.5698.

Keywords: balanced budget rule, divisible labor, labor income taxation, two movement patterns

Procedia PDF Downloads 122
4827 City-Wide Simulation on the Effects of Optimal Appliance Scheduling in a Time-of-Use Residential Environment

Authors: Rudolph Carl Barrientos, Juwaln Diego Descallar, Rainer James Palmiano

Abstract:

Household Appliance Scheduling Systems (HASS) coupled with a Time-of-Use (TOU) pricing scheme, a form of Demand Side Management (DSM), is not widely utilized in the Philippines’ residential electricity sector. This paper’s goal is to encourage distribution utilities (DUs) to adopt HASS and TOU by analyzing the effect of household schedulers on the electricity price and load profile in a residential environment. To establish this, a city based on an implemented survey is generated using Monte Carlo Analysis (MCA). Then, a Binary Particle Swarm Optimization (BPSO) algorithm-based HASS is developed considering user satisfaction, electricity budget, appliance prioritization, energy storage systems, solar power, and electric vehicles. The simulations were assessed under varying levels of user compliance. Results showed that the average electricity cost, peak demand, and peak-to-average ratio (PAR) of the city load profile were all reduced. Therefore, the deployment of the HASS and TOU pricing scheme is beneficial for both stakeholders.

Keywords: appliance scheduling, DSM, TOU, BPSO, city-wide simulation, electric vehicle, appliance prioritization, energy storage system, solar power

Procedia PDF Downloads 63
4826 Scheduling Residential Daily Energy Consumption Using Bi-criteria Optimization Methods

Authors: Li-hsing Shih, Tzu-hsun Yen

Abstract:

Because of the long-term commitment to net zero carbon emission, utility companies include more renewable energy supply, which generates electricity with time and weather restrictions. This leads to time-of-use electricity pricing to reflect the actual cost of energy supply. From an end-user point of view, better residential energy management is needed to incorporate the time-of-use prices and assist end users in scheduling their daily use of electricity. This study uses bi-criteria optimization methods to schedule daily energy consumption by minimizing the electricity cost and maximizing the comfort of end users. Different from most previous research, this study schedules users’ activities rather than household appliances to have better measures of users’ comfort/satisfaction. The relation between each activity and the use of different appliances could be defined by users. The comfort level is at the highest when the time and duration of an activity completely meet the user’s expectation, and the comfort level decreases when the time and duration do not meet expectations. A questionnaire survey was conducted to collect data for establishing regression models that describe users’ comfort levels when the execution time and duration of activities are different from user expectations. Six regression models representing the comfort levels for six types of activities were established using the responses to the questionnaire survey. A computer program is developed to evaluate electricity cost and the comfort level for each feasible schedule and then find the non-dominated schedules. The Epsilon constraint method is used to find the optimal schedule out of the non-dominated schedules. A hypothetical case is presented to demonstrate the effectiveness of the proposed approach and the computer program. Using the program, users can obtain the optimal schedule of daily energy consumption by inputting the intended time and duration of activities and the given time-of-use electricity prices.

Keywords: bi-criteria optimization, energy consumption, time-of-use price, scheduling

Procedia PDF Downloads 25
4825 Municipal Solid Waste Management and Analysis of Waste Generation: A Case Study of Bangkok, Thailand

Authors: Pitchayanin Sukholthaman

Abstract:

Gradually accumulated, the enormous amount of waste has caused tremendous adverse impacts to the world. Bangkok, Thailand, is chosen as an urban city of a developing country having coped with serious MSW problems due to the vast amount of waste generated, ineffective and improper waste management problems. Waste generation is the most important factor for successful planning of MSW management system. Thus, the prediction of MSW is a very important role to understand MSW distribution and characteristic; to be used for strategic planning issues. This study aims to find influencing variables that affect the amount of Bangkok MSW generation quantity.

Keywords: MSW generation, MSW quantity prediction, MSW management, multiple regression, Bangkok

Procedia PDF Downloads 379
4824 Local Revenue Generation: Its Contribution to the Development of the Municipality of Bacolod, Lanao Del Sur

Authors: Louvill M. Ozarraga

Abstract:

this study was designed to ascertain the concept of the revenue generation system of Bacolod, Lanao del Norte, through the completely enumerated elected officials and permanent employees sample respondents. The pertinent data were obtained through the use of a structured questionnaire and with the help of key informants. The study utilized a cross-sectional survey design to analyze and interpret the data using frequency count, percentage distribution, and weighted mean. For the major findings, the local revenue generation of the Municipality has increased by Php 4,465,394.21, roughly 73.52%, from the years 2018 to 2020. Administrative activities help the Municipality cope with development, namely, the issuance of ordinances, personnel augmentation, and collection strategies. Moreover, respondents were undecided about whether revenue generation contributed to infrastructures and purchases of assets. The majority of the respondents agreed that the municipality’s local revenue generation contributes to the social welfare of its constituents. Also, the respondents disagreed that locally generated revenue augments the 20% development fund. The study revealed that there is a big difference between the 2018 and 2020 Real Property Tax (RPT) collection. No committee was created to monitor and supervise the municipal revenue generation system. The Municipality, through a partnership with TESDA, provides skilled-job opportunity to its constituents and participants

Keywords: Local Revenue Generation: Its Contribution To The Development Of The Municipality Of Bacolod, Lanao Del Sur

Procedia PDF Downloads 51
4823 Reducing the Imbalance Penalty Through Artificial Intelligence Methods Geothermal Production Forecasting: A Case Study for Turkey

Authors: Hayriye Anıl, Görkem Kar

Abstract:

In addition to being rich in renewable energy resources, Turkey is one of the countries that promise potential in geothermal energy production with its high installed power, cheapness, and sustainability. Increasing imbalance penalties become an economic burden for organizations since geothermal generation plants cannot maintain the balance of supply and demand due to the inadequacy of the production forecasts given in the day-ahead market. A better production forecast reduces the imbalance penalties of market participants and provides a better imbalance in the day ahead market. In this study, using machine learning, deep learning, and, time series methods, the total generation of the power plants belonging to Zorlu Natural Electricity Generation, which has a high installed capacity in terms of geothermal, was estimated for the first one and two weeks of March, then the imbalance penalties were calculated with these estimates and compared with the real values. These modeling operations were carried out on two datasets, the basic dataset and the dataset created by extracting new features from this dataset with the feature engineering method. According to the results, Support Vector Regression from traditional machine learning models outperformed other models and exhibited the best performance. In addition, the estimation results in the feature engineering dataset showed lower error rates than the basic dataset. It has been concluded that the estimated imbalance penalty calculated for the selected organization is lower than the actual imbalance penalty, optimum and profitable accounts.

Keywords: machine learning, deep learning, time series models, feature engineering, geothermal energy production forecasting

Procedia PDF Downloads 74
4822 Migration and Identity Erosion: An Exploratory Study of First Generation Nigerian-Americans

Authors: Lolade Siyonbola

Abstract:

Nigerians are often celebrated as being the most educated cultural group in America. The cultural values and history that have led to this reality are particular to a generation that came of age post colonialism. Many of these cultural values have been passed down from post-colonial parent to millennial child, but most have not. This study, based on interviews and surveys of Nigerian millennials and their parents in the United States, explores the degree to which identity has been eroded in the millennial generation due to a lack of imparted cultural values and knowledge from the previous generation. Most of the subjects do not speak their native language or identify with their cultural heritage sufficiently to build ties with their native land. Most are experiencing some degree of identity crisis, and therefore limited self-actualization, with little to no support; as there are few successful tools available to this population. If governmental programs to reverse these trends are not implemented within this generation, the implications to the individual, family and home nation (Nigeria), will be felt for generations to come.

Keywords: identity, culture, self-actualization, social identity theory, migration, transnationalism, value systems

Procedia PDF Downloads 343
4821 Modeling and Validation of Microspheres Generation in the Modified T-Junction Device

Authors: Lei Lei, Hongbo Zhang, Donald J. Bergstrom, Bing Zhang, K. Y. Song, W. J. Zhang

Abstract:

This paper presents a model for a modified T-junction device for microspheres generation. The numerical model is developed using a commercial software package: COMSOL Multiphysics. In order to test the accuracy of the numerical model, multiple variables, such as the flow rate of cross-flow, fluid properties, structure, and geometry of the microdevice are applied. The results from the model are compared with the experimental results in the diameter of the microsphere generated. The comparison shows a good agreement. Therefore the model is useful in further optimization of the device and feedback control of microsphere generation if any.

Keywords: CFD modeling, validation, microsphere generation, modified T-junction

Procedia PDF Downloads 671
4820 Heat Transfer and Entropy Generation in a Partial Porous Channel Using LTNE and Exothermicity/Endothermicity Features

Authors: Mohsen Torabi, Nader Karimi, Kaili Zhang

Abstract:

This work aims to provide a comprehensive study on the heat transfer and entropy generation rates of a horizontal channel partially filled with a porous medium which experiences internal heat generation or consumption due to exothermic or endothermic chemical reaction. The focus has been given to the local thermal non-equilibrium (LTNE) model. The LTNE approach helps us to deliver more accurate data regarding temperature distribution within the system and accordingly to provide more accurate Nusselt number and entropy generation rates. Darcy-Brinkman model is used for the momentum equations, and constant heat flux is assumed for boundary conditions for both upper and lower surfaces. Analytical solutions have been provided for both velocity and temperature fields. By incorporating the investigated velocity and temperature formulas into the provided fundamental equations for the entropy generation, both local and total entropy generation rates are plotted for a number of cases. Bifurcation phenomena regarding temperature distribution and interface heat flux ratio are observed. It has been found that the exothermicity or endothermicity characteristic of the channel does have a considerable impact on the temperature fields and entropy generation rates.

Keywords: entropy generation, exothermicity or endothermicity, forced convection, local thermal non-equilibrium, analytical modelling

Procedia PDF Downloads 379
4819 The Effect of Advertising on Brand Choices of Z Generation Children and Their Social Media Consumption Habits

Authors: Hüseyin Altubaş, Hasret Aktaş, A. Mücahid Zengin

Abstract:

Children determine the direction of the power of consumption. They affect the decisions of their parents but they also reached to a significant purchasing power themselves. Children, who are turning interactive behavior to normal behavior are becoming the decision makers in a company’s survival. Companies that analyze this effective target audience can communicate successfully with children. Children, who are interactive individuals, are closer to advertising. They are almost talking better with advertising. They are not afraid to express their likings, as well as their dislikes. Children have an interactive lifestyle and they were exposed to the vast changes in technology after year 2000. They do not know a life without internet, they spend mobile life in internet. This Z generation is the new determinants of brands. Z generation finds it appropriate to be brand ambassadors and they completely changed traditional media and traditional consumer behavior. These children live social reality with virtual reality and they feed brands differently. Brands that interact with Z generation are affected by this feeding positively, while brands that keep interaction in traditional levels are affected negatively. In this research we examine the communication, advertising and brand behaviors of Z generation. We especially analyze this generation’s interaction with social media brands and their interactive attitudes.

Keywords: social media, Z generation, children, advertising, brand choice

Procedia PDF Downloads 525
4818 Attitudinal Change: A Major Therapy for Non–Technical Losses in the Nigerian Power Sector

Authors: Fina O. Faithpraise, Effiong O. Obisung, Azele E. Peter, Chris R. Chatwin

Abstract:

This study investigates and identifies consumer attitude as a major influence that results in non-technical losses in the Nigerian electricity supply sector. This discovery is revealed by the combination of quantitative and qualitative research to complete a survey. The dataset employed is a simple random sampling of households using electricity (public power supply), and the number of units chosen is based on statistical power analysis. The units were subdivided into two categories (household with and without electrical meters). The hypothesis formulated was tested and analyzed using a chi-square statistical method. The results obtained shows that the critical value for the household with electrical prepared meter (EPM) was (9.488 < 427.4) and those without electrical prepared meter (EPMn) was (9.488 < 436.1) with a p-value of 0.01%. The analysis demonstrated so far established the real-time position, which shows that the wrong attitude towards handling the electricity supplied (not turning off light bulbs and electrical appliances when not in use within the rooms and outdoors within 12 hours of the day) characterized the non-technical losses in the power sector. Therefore the adoption of efficient lighting attitudes in individual households as recommended by the researcher is greatly encouraged. The results from this study should serve as a model for energy efficiency and use for the improvement of electricity consumption as well as a stable economy.

Keywords: attitudinal change, household, non-technical losses, prepared meter

Procedia PDF Downloads 148
4817 Domestic Solar Hot Water Systems in Order to Reduce the Electricity Peak Demand in Assalouyeh

Authors: Roya Moradifar, Bijan Honarvar, Masoumeh Zabihi

Abstract:

The personal residential camps of South Pars gas complex are one of the few places where electric energy is used for the bath water heating. The widespread use of these devices is mainly responsible for the high peak of the electricity demand in the residential sector. In an attempt to deal with this issue, to reduce the electricity usage of the hot water, as an option, solar hot water systems have been proposed. However, despite the high incidence of solar radiation on the Assaloyeh about 20 MJ/m²/day, currently, there is no technical assessment quantifying the economic benefits on the region. The present study estimates the economic impacts resulting by the deployment of solar hot water systems in residential camp. Hence, the feasibility study allows assessing the potential of solar water heating as an alternative to reduce the peak on the electricity demand. In order to examine the potential of using solar energy in Bidkhoon residential camp two solar water heater packages as pilots were installed for restaurant and building. Restaurant package was damaged due to maintenance problems, but for the building package, we achieved the result of the solar fraction total 83percent and max energy saving 2895 kWh, the maximum reduction in CO₂ emissions calculated as 1634.5 kg. The results of this study can be used as a support tool to spread the use solar water heaters and create policies for South Pars Gas Complex.

Keywords: electrical energy, hot water, solar, South Pars Gas complex

Procedia PDF Downloads 168
4816 Effects of Using Alternative Energy Sources and Technologies to Reduce Energy Consumption and Expenditure of a Single Detached House

Authors: Gul Nihal Gugul, Merih Aydinalp-Koksal

Abstract:

In this study, hourly energy consumption model of a single detached house in Ankara, Turkey is developed using ESP-r building energy simulation software. Natural gas is used for space heating, cooking, and domestic water heating in this two story 4500 square feet four-bedroom home. Hourly electricity consumption of the home is monitored by an automated meter reading system, and daily natural gas consumption is recorded by the owners during 2013. Climate data of the region and building envelope data are used to develop the model. The heating energy consumption of the house that is estimated by the ESP-r model is then compared with the actual heating demand to determine the performance of the model. Scenarios are applied to the model to determine the amount of reduction in the total energy consumption of the house. The scenarios are using photovoltaic panels to generate electricity, ground source heat pumps for space heating and solar panels for domestic hot water generation. Alternative scenarios such as improving wall and roof insulations and window glazing are also applied. These scenarios are evaluated based on annual energy, associated CO2 emissions, and fuel expenditure savings. The pay-back periods for each scenario are also calculated to determine best alternative energy source or technology option for this home to reduce annual energy use and CO2 emission.

Keywords: ESP-r, building energy simulation, residential energy saving, CO2 reduction

Procedia PDF Downloads 165
4815 Statistical Characteristics of Distribution of Radiation-Induced Defects under Random Generation

Authors: P. Selyshchev

Abstract:

We consider fluctuations of defects density taking into account their interaction. Stochastic field of displacement generation rate gives random defect distribution. We determinate statistical characteristics (mean and dispersion) of random field of point defect distribution as function of defect generation parameters, temperature and properties of irradiated crystal.

Keywords: irradiation, primary defects, interaction, fluctuations

Procedia PDF Downloads 298
4814 Investigating Income Diversification Strategies into Off-Farm Activities Among Rural Households in Ethiopia

Authors: Kibret Berhanu Getinet

Abstract:

Off-farm income diversification by farm rural households has gained the attention of researchers and policymakers due to the fact that agriculture failed to meet the needs of people in developing countries like Ethiopia. The objective of this study was to investigate income diversification strategies into off-farm activities among rural households in Hawassa Zuria Woreda, Sidama National Regional State, Ethiopia. The study used primary and secondary data sources for the primary data collection questionnaire employed as a data collection instrument. A multistage sampling technique was used to collect data from a total of 197 sample households from four kebeles of the study area. Descriptive statistics, as well as econometrics methods of data analysis, were employed. The descriptive statistics result indicates that the majority of sample rural households (68.53 %) have engaged in off-farm income diversification activities while the remaining 31.47% of households did not participate in the diversification in the study area. The choice of participants among the strategies indicates that 6.60% of respondents participated in off-farm wage employment, 30.46% participated in off-farm self-employment, and about 31.47% of them participated in both off-farm wage employment. The study revealed that the share of off-farm income in total annual earnings of households was about 48.457%, and thus, the off-farm diversification significantly contributes to the rural household income. Moreover, binary and multinomial logistic regression models were employed to identify factors that affect the participation and the choices of the off-farm income diversification strategies, respectively. The binary logit model result indicated that agro-ecological zone, education status of the households, available technical skills of the household, household saving, total livestock owned by the households, access to electricity, road access and being married of household head were significant and positively affected the chance of diversification in off-farm activities while the on-farm income of households is negatively affected the chance of diversification. Similarly, the multinomial logistic regression model estimate revealed that agroecological zone, on-farm income, available technical skills, household savings, and access to electricity are positively related and significantly influenced the household’s choice of employment into off-farm wage employment. The off-farm self-employment diversification choice is significantly influenced by on-farm income, available technical skills, household savings, total livestock owned, and access to electricity. Moreover, the result showed that the factors that affect the choice of farm households to engage in both off-farm wage and self-employment are ecological zone, education status, on-farm income, available technical skills, household own saving, market access, total livestock owned, access to electricity and road access. Thus, due attention should be given to addressing the demographic, socio-economic, and institutional constraints to strengthen off-farm income diversification strategies to improve the income of rural households.

Keywords: off-farm, incoem, diversification, logit model

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4813 Active Learning Techniques in Engineering Education

Authors: H. M. Anitha, Anusha N. Rao

Abstract:

The current developments in technology and ideas have given entirely new dimensions to the field of research and education. New delivery methods are proposed which is an added feature to the engineering education. Particularly, more importance is given to new teaching practices such as Information and Communication Technologies (ICT). It is vital to adopt the new ICT methods which lead to the emergence of novel structure and mode of education. The flipped classroom, think pair share and peer instruction are the latest pedagogical methods which give students to learn the course. This involves students to watch video lectures outside the classroom and solve the problems at home. Students are engaged in group discussions in the classroom. These are the active learning methods wherein the students are involved diversely to learn the course. This paper gives a comprehensive study of past and present research which is going on with flipped classroom, thinks pair share activity and peer instruction.

Keywords: flipped classroom, think pair share, peer instruction, active learning

Procedia PDF Downloads 359
4812 Airliner-UAV Flight Formation in Climb Regime

Authors: Pavel Zikmund, Robert Popela

Abstract:

Extreme formation is a theoretical concept of self-sustain flight when a big Airliner is followed by a small UAV glider flying in airliner’s wake vortex. The paper presents results of climb analysis with a goal to lift the gliding UAV to airliner’s cruise altitude. Wake vortex models, the UAV drag polar and basic parameters and airliner’s climb profile are introduced at first. Then, flight performance of the UAV in the wake vortex is evaluated by analytical methods. Time history of optimal distance between the airliner and the UAV during the climb is determined. The results are encouraging, therefore available UAV drag margin for electricity generation is figured out for different vortex models.

Keywords: flight in formation, self-sustained flight, UAV, wake vortex

Procedia PDF Downloads 405
4811 Local Revenue Generation: Its Contribution to the Development of the Municipality of Bacolod, Lanao Del Norte

Authors: Louvill Manangan Ozarraga

Abstract:

this study was designed to ascertain the concept of revenue generation system of Bacolod, Lanao del Norte, through the completely enumerated elected officials and permanent employees sample respondents. The pertinent data were obtained through the use of structured questionnaire and with the help of key informants. The study utilized a cross-sectional survey design to analyze and interpret the data using frequency count, percentage distribution, and weighted mean. For the major findings, the local revenue generation of the Municipality has increased by Php 4,465,394.21 roughly 73.52% from years 2018 to 2020. Administrative activities help the Municipality cope up with development namely, issuance of ordinance, personnel augmentation and collection strategies. Moreover, respondents were undecided whether revenue generation contributed to infrastructures and purchases of assets. Majority of the respondents agreed that the municipality’s local revenue generation contributes to the social welfare of its constituents. Also, the respondents disagreed that locally generated revenue augments the 20% development fund. The study revealed that there is a big difference on the 2018 and 2020 Real Property Tax (RPT) collection. No committee was created to monitor and supervise the municipal revenue generation system. The Municipality, through partnership with TESDA, provides skilled-job opportunity to its constituents and participants.

Keywords: contribution, development, Bacolod Lanao del Norte, revenue generation system

Procedia PDF Downloads 53
4810 Efficient Solid Oxide Electrolysers for Syn-Gas Generation Using Renewable Energy

Authors: G. Kaur, A. P. Kulkarni, S. Giddey

Abstract:

Production of fuels and chemicals using renewable energy is a promising way for large-scale energy storage and export. Solid oxide electrolysers (SOEs) integrated with renewable source of energy can produce 'Syngas' H₂/CO from H₂O/CO₂ in the desired ratio for further conversion to liquid fuels. As only a waste CO₂ from industrial and power generation processes is utilized in these processes, this approach is CO₂ neutral compared to using fossil fuel feedstock. In addition, the waste heat from industrial processes or heat from solar thermal concentrators can be effectively utilised in SOEs to further reduce the electrical requirements by up to 30% which boosts overall energy efficiency of the process. In this paper, the electrochemical performance of various novel steam/CO₂ reduction electrodes (cathode) would be presented. The efficiency and lifetime degradation data for single cells and a stack would be presented along with the response of cells to variable electrical load input mimicking the intermittent nature of the renewable energy sources. With such optimisation, newly developed electrodes have been tested for 500+ hrs with Faraday efficiency (electricity to fuel conversion efficiency) up to 95%, and thermal efficiency in excess of 70% based upon energy content of the syngas produced.

Keywords: carbon dioxide, steam conversion, electrochemical system, energy storage, fuel production, renewable energy

Procedia PDF Downloads 201
4809 First-Generation College Students and Persistence: A Phenomenological Study of Students’ Experiences in Indonesian Higher Education

Authors: Taufik Mulyadin

Abstract:

The tuition reform for public colleges that the Indonesian government initiated and has implemented since 2013 resulted in the growing number of college students from low-income families, many of whose parents did not attend college. This study sought to examine the experiences of persistence for Indonesian first-generation college students in public universities utilizing social capital as a framework. It is a qualitative study with a phenomenological approach primarily to capture the essence of how Indonesian first-generation college students interpret, process, and experience their persistence during college years. Fifteen Indonesian young college graduates were involved as well as questionnaire and interview were employed for data collection in this study. It revealed certain themes from the experiences that first-generation college students attributed to their persistence: (a) family encouragement, (b) support from friends, (c) guidance from faculty and staff, (d) fund of knowledge they bring with them, (e) financial aid availability, and (f) self-motivation. By examining first-generation college students’ voices, Indonesian public universities can better support, engage, and retain this group of students who were historically struggled to persist in college and complete their degree.

Keywords: first-generation student, Indonesian higher education, persistence, public universities

Procedia PDF Downloads 233
4808 Energy Communities from Municipality Level to Province Level: A Comparison Using Autoregressive Integrated Moving Average Model

Authors: Amro Issam Hamed Attia Ramadan, Marco Zappatore, Pasquale Balena, Antonella Longo

Abstract:

Considering the energetic crisis that is hitting Europe, it becomes more and more necessary to change the energy policies to depend less on fossil fuels and replace them with energy from renewable sources. This has triggered the urge to use clean energy not only to satisfy energy needs and fulfill the required consumption but also to decrease the danger of climatic changes due to harmful emissions. Many countries have already started creating energetic communities based on renewable energy sources. The first step to understanding energy needs in any place is to perfectly know the consumption. In this work, we aim to estimate electricity consumption for a municipality that makes up part of a rural area located in southern Italy using forecast models that allow for the estimation of electricity consumption for the next ten years, and we then apply the same model to the province where the municipality is located and estimate the future consumption for the same period to examine whether it is possible to start from the municipality level to reach the province level when creating energy communities.

Keywords: ARIMA, electricity consumption, forecasting models, time series

Procedia PDF Downloads 123
4807 Hybrid Genetic Approach for Solving Economic Dispatch Problems with Valve-Point Effect

Authors: Mohamed I. Mahrous, Mohamed G. Ashmawy

Abstract:

Hybrid genetic algorithm (HGA) is proposed in this paper to determine the economic scheduling of electric power generation over a fixed time period under various system and operational constraints. The proposed technique can outperform conventional genetic algorithms (CGAs) in the sense that HGA make it possible to improve both the quality of the solution and reduce the computing expenses. In contrast, any carefully designed GA is only able to balance the exploration and the exploitation of the search effort, which means that an increase in the accuracy of a solution can only occure at the sacrifice of convergent speed, and vice visa. It is unlikely that both of them can be improved simultaneously. The proposed hybrid scheme is developed in such a way that a simple GA is acting as a base level search, which makes a quick decision to direct the search towards the optimal region, and a local search method (pattern search technique) is next employed to do the fine tuning. The aim of the strategy is to achieve the cost reduction within a reasonable computing time. The effectiveness of the proposed hybrid technique is verified on two real public electricity supply systems with 13 and 40 generator units respectively. The simulation results obtained with the HGA for the two real systems are very encouraging with regard to the computational expenses and the cost reduction of power generation.

Keywords: genetic algorithms, economic dispatch, pattern search

Procedia PDF Downloads 403
4806 Occupational Attainment of Second Generation of Ethnic Minority Immigrants in the UK

Authors: Rukhsana Kausar, Issam Malki

Abstract:

The integration and assimilation of ethnic minority immigrants (EMIs) and their subsequent generations remains a serious unsettled issue in most of the host countries. This study conducts the labour market gender analysis to investigate specifically whether second generation of ethnic minority immigrants in the UK is gaining access to professional and managerial employment and advantaged occupational positions on par with their native counterparts. The data used to examine the labour market achievements of EMIs is taken from Labour Force Survey (LFS) for the period 2014-2018. We apply a multivalued treatment under ignorability as proposed by Cattaneo (2010), which refers to treatment effects under the assumptions of (i) selection – on – observables and (ii) common support. We report estimates of Average Treatment Effect (ATE), Average Treatment Effect on the Treated (ATET), and Potential Outcomes Means (POM) using three estimators, including the Regression Adjustment (RA), Augmented Inverse Probability Weighting (AIPW) and Inverse Probability Weighting- Regression Adjustment (IPWRA). We consider two cases: the case with four categories where the first-generation natives are the base category, the second case combine all natives as a base group. Our findings suggest the following. Under Case 1, the estimated probabilities and differences across groups are consistently similar and highly significant. As expected, first generation natives have the highest probability for higher career attainment among both men and women. The findings also suggest that first generation immigrants perform better than the remaining two groups, including the second-generation natives and immigrants. Furthermore, second generation immigrants have higher probability to attain higher professional career, while this is lower for a managerial career. Similar conclusions are reached under Case 2. That is to say that both first – generation and second – generation immigrants have a lower probability for higher career and managerial attainment. First – generation immigrants are found to perform better than second – generation immigrants.

Keywords: immigrnats, second generation, occupational attainment, ethnicity

Procedia PDF Downloads 78
4805 Cavity-Type Periodically-Poled LiNbO3 Device for Highly-Efficient Third-Harmonic Generation

Authors: Isao Tomita

Abstract:

We develop a periodically-poled LiNbO3 (PPLN) device for highly-efficient third-harmonic generation (THG), where the THG efficiency is enhanced with a cavity. THG can usually be produced via χ(3)-nonlinear materials by optical pumping with very high pump-power. Instead, we here propose THG by moderate-power pumping through a specially-designed PPLN device containing only χ(2)-nonlinearity, where sum-frequency generation in the χ(2) process is employed for the mixing of a pump beam and a second-harmonic-generation (SHG) beam produced from the pump beam. The cavity is designed to increase the SHG power with dichroic mirrors attached to both ends of the device that perfectly reflect the SHG beam back to the device and yet let the pump and THG beams pass through the mirrors. This brings about a THG-power enhancement because of THG power proportional to the enhanced SHG power. We examine the THG-efficiency dependence on the mirror reflectance and show that very high THG-efficiency is obtained at moderate pump-power when compared with that of a cavity-free PPLN device.

Keywords: cavity, periodically-poled LiNbO₃, sum-frequency generation, third-harmonic generation

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4804 Solar Energy Generation Based Urban Development: A Case of Jodhpur City

Authors: A. Kumar, V. Devadas

Abstract:

India has the most year-round favorable sunny conditions along with the second-highest solar irradiation in the world, the country holds the potential to become the global solar hub. The solar and wind-based generation capacity has skyrocketed in India with the successful effort of the Ministry of Renewable Energy, whereas the potential of rooftop based solar power generation has yet to be explored for proposed solar cities in India. The research aims to analyze the gap in the energy scenario in Jodhpur City and proposes interventions of solar energy generation systems as a catalyst for urban development. The research is based on the system concept which deals with simulation between the city system as a whole and its interactions between different subsystems. A system-dynamics based mathematical model is developed by identifying the control parameters using regression and correlation analysis to assess the gap in energy sector. The base model validation is done using the past 10 years timeline data collected from secondary sources. Further, energy consumption and solar energy generation-based projection are made for testing different scenarios to conclude the feasibility for maintaining the city level energy independence till 2031.

Keywords: city, consumption, energy, generation

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4803 Effect of Internal Heat Generation on Free Convective Power Law Variable Temperature Past Vertical Plate Considering Exponential Variable Viscosity and Thermal Diffusivity

Authors: Tania Sharmin Khaleque, Mohammad Ferdows

Abstract:

The flow and heat transfer characteristics of a convection with temperature-dependent viscosity and thermal diffusivity along a vertical plate with internal heat generation effect have been studied. The plate temperature is assumed to follow a power law of the distance from the leading edge. The resulting governing two-dimensional equations are transformed using suitable transformations and then solved numerically by using fifth order Runge-Kutta-Fehlberg scheme with a modified version of the Newton-Raphson shooting method. The effects of the various parameters such as variable viscosity parameter β_1, the thermal diffusivity parameter β_2, heat generation parameter c and the Prandtl number Pr on the velocity and temperature profiles, as well as the local skin- friction coefficient and the local Nusselt number are presented in tabular form. Our results suggested that the presence of internal heat generation leads to increase flow than that of without exponentially decaying heat generation term.

Keywords: free convection, heat generation, thermal diffusivity, variable viscosity

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4802 A Study of the Carbon Footprint from a Liquid Silicone Rubber Compounding Facility in Malaysia

Authors: Q. R. Cheah, Y. F. Tan

Abstract:

In modern times, the push for a low carbon footprint entails achieving carbon neutrality as a goal for future generations. One possible step towards carbon footprint reduction is the use of more durable materials with longer lifespans, for example, silicone data cableswhich show at least double the lifespan of similar plastic products. By having greater durability and longer lifespans, silicone data cables can reduce the amount of trash produced as compared to plastics. Furthermore, silicone products don’t produce micro contamination harmful to the ocean. Every year the electronics industry produces an estimated 5 billion data cables for USB type C and lightning data cables for tablets and mobile phone devices. Material usage for outer jacketing is 6 to 12 grams per meter. Tests show that the product lifespan of a silicone data cable over plastic can be doubled due to greater durability. This can save at least 40,000 tonnes of material a year just on the outer jacketing of the data cable. The facility in this study specialises in compounding of liquid silicone rubber (LSR) material for the extrusion process in jacketing for the silicone data cable. This study analyses the carbon emissions from the facility, which is presently capable of producing more than 1,000 tonnes of LSR annually. This study uses guidelines from the World Business Council for Sustainable Development (WBCSD) and World Resources Institute (WRI) to define the boundaries of the scope. The scope of emissions is defined as 1. Emissions from operations owned or controlled by the reporting company, 2. Emissions from the generation of purchased or acquired energy such as electricity, steam, heating, or cooling consumed by the reporting company, and 3. All other indirect emissions occurring in the value chain of the reporting company, including both upstream and downstream emissions. As the study is limited to the compounding facility, the system boundaries definition according to GHG protocol is cradle-to-gate instead of cradle-to-grave exercises. Malaysia’s present electricity generation scenario was also used, where natural gas and coal constitute the bulk of emissions. Calculations show the LSR produced for the silicone data cable with high fire retardant capability has scope 1 emissions of 0.82kg CO2/kg, scope 2 emissions of 0.87kg CO2/kg, and scope 3 emissions of 2.76kg CO2/kg, with a total product carbon footprint of 4.45kg CO2/kg. This total product carbon footprint (Cradle-to-gate) is comparable to the industry and to plastic materials per tonne of material. Although per tonne emission is comparable to plastic material, due to greater durability and longer lifespan, there can be significantly reduced use of LSR material. Suggestions to reduce the calculated product carbon footprint in the scope of emissions involve 1. Incorporating the recycling of factory silicone waste into operations, 2. Using green renewable energy for external electricity sources and 3. Sourcing eco-friendly raw materials with low GHG emissions.

Keywords: carbon footprint, liquid silicone rubber, silicone data cable, Malaysia facility

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4801 Forecasting Electricity Spot Price with Generalized Long Memory Modeling: Wavelet and Neural Network

Authors: Souhir Ben Amor, Heni Boubaker, Lotfi Belkacem

Abstract:

This aims of this paper is to forecast the electricity spot prices. First, we focus on modeling the conditional mean of the series so we adopt a generalized fractional -factor Gegenbauer process (k-factor GARMA). Secondly, the residual from the -factor GARMA model has used as a proxy for the conditional variance; these residuals were predicted using two different approaches. In the first approach, a local linear wavelet neural network model (LLWNN) has developed to predict the conditional variance using the Back Propagation learning algorithms. In the second approach, the Gegenbauer generalized autoregressive conditional heteroscedasticity process (G-GARCH) has adopted, and the parameters of the k-factor GARMA-G-GARCH model has estimated using the wavelet methodology based on the discrete wavelet packet transform (DWPT) approach. The empirical results have shown that the k-factor GARMA-G-GARCH model outperform the hybrid k-factor GARMA-LLWNN model, and find it is more appropriate for forecasts.

Keywords: electricity price, k-factor GARMA, LLWNN, G-GARCH, forecasting

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