Search results for: cooling methods
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 16118

Search results for: cooling methods

15218 Coordinated Voltage Control in Radial Distribution System with Distributed Generators Using Sensitivity Analysis

Authors: Anubhav Shrivastava Shivarudraswamy, Bhat Lakshya

Abstract:

Distributed generation has indeed become a major area of interest in recent years. Distributed generation can address a large number of loads in a power line and hence has better efficiency over the conventional methods. However, there are certain drawbacks associated with it, an increase in voltage being the major one. This paper addresses the voltage control at the buses for an IEEE 30 bus system by regulating reactive power. For carrying out the analysis, the suitable location for placing distributed generators (DG) is identified through load flow analysis and seeing where the voltage profile is dipping. MATLAB programming is used to regulate the voltage at all buses within +/- 5% of the base value even after the introduction of DGs. Three methods for regulation of voltage are discussed. A sensitivity based analysis is then carried out to determine the priority among the various methods listed in the paper.

Keywords: distributed generators, distributed system, reactive power, voltage control, sensitivity analysis

Procedia PDF Downloads 659
15217 One-Step Time Series Predictions with Recurrent Neural Networks

Authors: Vaidehi Iyer, Konstantin Borozdin

Abstract:

Time series prediction problems have many important practical applications, but are notoriously difficult for statistical modeling. Recently, machine learning methods have been attracted significant interest as a practical tool applied to a variety of problems, even though developments in this field tend to be semi-empirical. This paper explores application of Long Short Term Memory based Recurrent Neural Networks to the one-step prediction of time series for both trend and stochastic components. Two types of data are analyzed - daily stock prices, that are often considered to be a typical example of a random walk, - and weather patterns dominated by seasonal variations. Results from both analyses are compared, and reinforced learning framework is used to select more efficient between Recurrent Neural Networks and more traditional auto regression methods. It is shown that both methods are able to follow long-term trends and seasonal variations closely, but have difficulties with reproducing day-to-day variability. Future research directions and potential real world applications are briefly discussed.

Keywords: long short term memory, prediction methods, recurrent neural networks, reinforcement learning

Procedia PDF Downloads 229
15216 Impact of Climate Change on Energy Consumption of the Residential Building Stock in Turkey

Authors: Sadik Yigit

Abstract:

The energy consumed in the buildings constitutes a large portion of the total energy consumption in the world. In this study, it was aimed to measure the impact of climate change on the energy consumption of residential building stock by analyzing a typical mid-rise residential building in four different climate regions of Turkey. An integrated system was developed using the "Distribution Evolutionary Algorithms in Python" tool and Energy Plus. By using the developed integrated system, the energy performance of the typical residential building was analyzed under the effect of different climate change scenarios. The results indicated that predicted overheating will be experienced in the future, which will significantly increase the cooling energy loads of the buildings. In addition, design solutions to improve the future energy performance of the buildings were proposed, considering budget constraints. The results of the study will guide researchers studying in this area of research and designers in the sector in finding climate change resilient design solutions.

Keywords: energy_efficient, residential buildings, climate change, energyplus

Procedia PDF Downloads 104
15215 Resource Efficiency within Current Production

Authors: Sarah Majid Ansari, Serjosha Wulf, Matthias Goerke

Abstract:

In times of global warming and the increasing shortage of resources, sustainable production is becoming more and more inevitable. Companies cannot only heighten their competitiveness but also contribute positively to environmental protection through efficient energy and resource consumption. Regarding this, technical solutions are often preferred during production, although organizational and process-related approaches also offer great potential. This project focuses on reducing resource usage, with a special emphasis on the human factor. It is the aspiration to develop a methodology that systematically implements and embeds suitable and individual measures and methods regarding resource efficiency throughout the entire production. The measures and methods established help employees handle resources and energy more sensitively. With this in mind, this paper also deals with the difficulties that can occur during the sensitization of employees and the implementation of these measures and methods. In addition, recommendations are given on how to avoid such difficulties.

Keywords: implementation, human factors, production plants, resource efficiency

Procedia PDF Downloads 481
15214 Study on Pressurized Reforming System for the Application of Hydrogen Permeable Membrane Applying to Proton Exchange Membrane Fuel Cell

Authors: Kwangho Lee, Joongmyeon Bae

Abstract:

Fuel cells are spotlighted in the world for being highly efficient and environmentally friendly. A hydrogen fuel for a fuel cell is obtained from a number of sources. Most of fuel cell for APU(Auxiliary power unit) system using diesel fuel as a hydrogen source. Diesel fuel has many advantages, such as high hydrogen storage density, easy to transport and also well-infra structure. However, conventional diesel reforming system for PEMFC(Proton exchange membrane fuel cell) requires a large volume and complex CO removal system for the lower the CO level to less than 10ppm. In addition, the PROX(Preferential Oxidation) reaction cooling load is needed because of the strong exothermic reaction. However, the hydrogen separation membrane that we propose can be eliminated many disadvantages, because the volume is small and permeates only pure hydrogen. In this study, we were conducted to the pressurized diesel reforming and water-gas shift reaction experiment for the hydrogen permeable membrane application.

Keywords: hydrogen, diesel, reforming, ATR, WGS, PROX, membrane, pressure

Procedia PDF Downloads 430
15213 Systematic Analysis of Logistics Location Search Methods under Aspects of Sustainability

Authors: Markus Pajones, Theresa Steiner, Matthias Neubauer

Abstract:

Selecting a logistics location is vital for logistics providers, food retailing and other trading companies since the selection poses an essential factor for economic success. Therefore various location search methods like cost-benefit analysis and others are well known and under usage. The development of a logistics location can be related to considerable negative effects for the eco system such as sealing the surface, wrecking of biodiversity or CO2 and noise emissions generated by freight and commuting traffic. The increasing importance of sustainability demands for taking an informed decision when selecting a logistics location for the future. Sustainability considers economic, ecologic and social aspects which should be equally integrated in the process of location search. Objectives of this paper are to define various methods which support the selection of sustainable logistics locations and to generate knowledge about the suitability, assets and limitations of the methods within the selection process. This paper investigates the role of economical, ecological and social aspects when searching for new logistics locations. Thereby, related work targeted towards location search is analyzed with respect to encoded sustainability aspects. In addition, this research aims to gain knowledge on how to include aspects of sustainability and take an informed decision when searching for a logistics location. As a result, a decomposition of the various location search methods in there components leads to a comparative analysis in form of a matrix. The comparison within a matrix enables a transparent overview about the mentioned assets and limitations of the methods and their suitability for selecting sustainable logistics locations. A further result is to generate knowledge on how to combine the separate methods to a new method for a more efficient selection of logistics locations in the context of sustainability. Future work will especially investigate the above mentioned combination of various location search methods. The objective is to develop an innovative instrument, which supports the search for logistics locations with a focus on a balanced sustainability (economy, ecology, social). Because of an ideal selection of logistics locations, induced traffic should be reduced and a mode shift to rail and public transport should be facilitated.

Keywords: commuting traffic, freight traffic, logistics location search, location search method

Procedia PDF Downloads 321
15212 Evaluation of Iranian Standard for Assessment of Liquefaction Potential of Cohesionless Soils Based on SPT

Authors: Reza Ziaie Moayad, Azam Kouhpeyma

Abstract:

In-situ testing is preferred to evaluate the liquefaction potential in cohesionless soils due to high disturbance during sampling. Although new in-situ methods with high accuracy have been developed, standard penetration test, the simplest and the oldest in-situ test, is still used due to the profusion of the recorded data. This paper reviews the Iranian standard of evaluating liquefaction potential in soils (codes 525) and compares the liquefaction assessment methods based on SPT results on cohesionless soil in this standard with the international standards. To this, methods for assessing liquefaction potential which are presented by Cetin et al. (2004), Boulanger and Idriss (2014) are compared with what is presented in standard 525. It is found that although the procedure used in Iranian standard of evaluating the potential of liquefaction has not been updated according to the new findings, it is a conservative procedure.

Keywords: cohesionless soil, liquefaction, SPT, standard 525

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15211 Thermal Characterization of Smart and Large-Scale Building Envelope System in a Subtropical Climate

Authors: Andrey A. Chernousov, Ben Y. B. Chan

Abstract:

The thermal behavior of a large-scale, phase change material (PCM) enhanced building envelope system was studied in regard to the need for pre-fabricated construction in subtropical regions. The proposed large-scale envelope consists of a reinforced aluminum skin, insulation core, phase change material and reinforced gypsum board. The PCM impact on an energy efficiency of an enveloped room was resolved by validation of the Energy Plus numerical scheme and optimization of a smart material location in the core. The PCM location was optimized by a minimization method of a cooling energy demand. It has been shown that there is good agreement between the test and simulation results. The optimal location of the PCM layer in Hong Kong summer conditions has been then recomputed for core thicknesses of 40, 60 and 80 mm. A non-dimensional value of the optimal PCM location was obtained to be same for all the studied cases and the considered external and internal conditions.

Keywords: thermal performance, phase change material, energy efficiency, PCM optimization

Procedia PDF Downloads 402
15210 The Study of Rapid Entire Body Assessment and Quick Exposure Check Correlation in an Engine Oil Company

Authors: Mohammadreza Ashouria, Majid Motamedzadeb

Abstract:

Rapid Entire Body Assessment (REBA) and Quick Exposure Check (QEC) are two general methods to assess the risk factors of work-related musculoskeletal disorders (WMSDs). This study aimed to compare ergonomic risk assessment outputs from QEC and REBA in terms of agreement in distribution of postural loading scores based on analysis of working postures. This cross-sectional study was conducted in an engine oil company in which 40 jobs were studied. A trained occupational health practitioner observed all jobs. Job information was collected to ensure the completion of ergonomic risk assessment tools, including QEC, and REBA. The result revealed that there was a significant correlation between final scores (r=0.731) and the action levels (r =0.893) of two applied methods. Comparison between the action levels and final scores of two methods showed that there was no significant difference among working departments. Most of the studied postures acquired low and moderate risk level in QEC assessment (low risk=20%, moderate risk=50% and High risk=30%) and in REBA assessment (low risk=15%, moderate risk=60% and high risk=25%).There is a significant correlation between two methods. They have a strong correlation in identifying risky jobs and determining the potential risk for incidence of WMSDs. Therefore, there is a possibility for researchers to apply interchangeably both methods, for postural risk assessment in appropriate working environments.

Keywords: observational method, QEC, REBA, musculoskeletal disorders

Procedia PDF Downloads 361
15209 Anharmonic Behavior in BaTiO3: Investigation by Raman Spectroscopy

Authors: M. D. Fontana, I. Bejaoui Ouni, D. Chapron, H. Aroui

Abstract:

BaTiO3 (BT) is a well known ferroelectric material which has been thoroughly studied during several decades since it undergoes successive cubic-tetragonal-orthorhombic-rhombohedral phase transitions on cooling. It has several ferroelectric properties that allow it to be a good material for electronic applications such as the design of ferroelectric memories and pyroelectric elements. In the present work, we report the analysis of temperature dependence of Raman frequency and damping of the A1 modes polarized along the FE c axis as well as the optical phonons E corresponding to the ionic motions in the plane normal to c. Measurements were carried out at different temperatures ranging from 298 to 408 K (tetragonal phase) within different scattering configurations. Spectroscopic parameters of BT have determined using a high resolution Raman spectrometer and a fitting program. All the first order frequency modes exhibit a quasi linear decrease as function of the temperature, except for the A1[TO1], E[TO2] and E[TO4] lines which reveal a parabolic dependence illustrating an anharmonic process. The phonon frequency downshifts and damping evolutions are interpreted in terms of normal volume expansion and third- and fourth-order anharmonic potentials.

Keywords: BaTiO3, Raman spectroscopy, frequency, damping, anharmonic potential

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15208 Thermal Hydraulic Analysis of the IAEA 10MW Benchmark Reactor under Normal Operating Condition

Authors: Hamed Djalal

Abstract:

The aim of this paper is to perform a thermal-hydraulic analysis of the IAEA 10 MW benchmark reactor solving analytically and numerically, by mean of the finite volume method, respectively the steady state and transient forced convection in rectangular narrow channel between two parallel MTR-type fuel plates, imposed under a cosine shape heat flux. A comparison between both solutions is presented to determine the minimal coolant velocity which can ensure a safe reactor core cooling, where the cladding temperature should not reach a specific safety limit 90 °C. For this purpose, a computer program is developed to determine the principal parameter related to the nuclear core safety, such as the temperature distribution in the fuel plate and in the coolant (light water) as a function of the inlet coolant velocity. Finally, a good agreement is noticed between the both analytical and numerical solutions, where the obtained results are displayed graphically.

Keywords: forced convection, pressure drop, thermal hydraulic analysis, vertical heated rectangular channel

Procedia PDF Downloads 154
15207 Energy Efficient Shading Strategies for Windows of Hospital ICUs in the Desert

Authors: A. Sherif, A. El Zafarany, R. Arafa

Abstract:

Hospitals, everywhere, are considered heavy energy consumers. Hospital Intensive Care Unit spaces pose a special challenge, where design guidelines requires the provision of external windows for day-lighting and external view. Window protection strategies could be employed to reduce energy loads without detriment effect on comfort or health care. This paper addresses the effectiveness of using various window strategies on the annual cooling, heating and lighting energy use of a typical Hospital Intensive Unit space. Series of experiments were performed using the EnergyPlus simulation software for a typical Intensive Care Unit (ICU) space in Cairo, located in the Egyptian desert. This study concluded that the use of shading systems is more effective in conserving energy in comparison with glazing of different types, in the Cairo ICUs. The highest energy savings in the West and South orientations were accomplished by external perforated solar screens, followed by overhangs positioned at a protection angle of 45°.

Keywords: energy, hospital, intensive care units, shading

Procedia PDF Downloads 289
15206 High Unmet Need and Factors Associated with Utilization of Contraceptive Methods among Women from the Digo Community of Kwale, Kenya

Authors: Mochache Vernon, Mwakusema Omar, Lakhani Amyn, El Busaidy Hajara, Temmerman Marleen, Gichangi Peter

Abstract:

Background: Utilization of contraceptive methods has been associated with improved maternal and child health (MCH) outcomes. Unfortunately, there has been sub-optimal uptake of contraceptive services in the developing world despite significant resources being dedicated accordingly. It is imperative to granulate factors that could influence uptake and utilization of contraception. Methodology: Between March and December 2015, we conducted a mixed-methods cross-sectional study among women of reproductive age (18-45 years) from a pre-dominantly rural coastal Kenyan community. Qualitative approaches involved focus group discussions as well as a series of key-informant interviews. We also administered a sexual and reproductive health survey questionnaire at the household level. Results: We interviewed 745 women from 15 villages in Kwale County. The median (interquartile range, IQR) age was 29 (23-37) while 76% reported being currently in a marital union. Eighty-seven percent and 85% of respondents reported ever attending school and ever giving birth, respectively. Respondents who had ever attended school were more than twice as likely to be using contraceptive methods [Odds Ratio, OR = 2.1, 95% confidence interval, CI: 1.4-3.4, P = 0.001] while those who had ever given birth were five times as likely to be using these methods [OR = 5.0, 95% CI: 1.7-15.0, P = 0.004]. The odds were similarly high among women who reported attending antenatal care (ANC) [OR = 4.0, 95% CI: 1.1-14.8, P = 0.04] as well as those who expressly stated that they did not want any more children or wanted to wait longer before getting another child [OR = 6.7, 95% CI: 3.3-13.8, P<0.0001]. Interviewees reported deferring to the ‘wisdom’ of an older maternal figure in the decision-making process. Conclusions: Uptake and utilization of contraceptive methods among Digo women from Kwale, Kenya is positively associated with demand-side factors including educational attainment, previous birth experience, ANC attendance and a negative future fertility desire. Interventions to improve contraceptive services should focus on engaging dominant maternal figures in the community.

Keywords: unmet need, utilization of contraceptive methods, women, Digo community

Procedia PDF Downloads 183
15205 Geothermal Resources of Saudi Arabia: An Update

Authors: Aref Lashin

Abstract:

Saudi Arabia vision of 2030 calls for the diversification of energy sources in the Kingdom. Accordingly, Saudi Arabia has launched a promising plan aims to gradually power the major industrial activities in country by renewable and low carbon energy sources. The geothermal sources are among the promising renewable sources that can support the achievement of the country vision and energy mix plan. Saudi Arabia is enriched with several geothermal resources especially in the western and southwestern regions along the Red Sea region. This paper will give an overview on the different geothermal resources (Hydrothermal, Harrats volcanic eruptions and hot dry rocks) of Saudi Arabia, their categories and classifications as well as the different exploration (Geophysical, geological, geochemical, etc) and drilling enhanced during the last few decades. The economic viability and the possible contribution of geothermal resources in the future of renewable energy of Saudi Arabia is discussed. Some case studies from Jizan, Al-Lith, Harrats and Midyan areas are demonstrated. Scenarios of different low and high geothermal applications for possible power generations, as well as other low-grade utilizations, e.g. direct use, district heating & cooling, medical therapy, etc., are presented.

Keywords: KSA vison 2023, energy mix, geothermal resources, applications, Saudi Arabia

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15204 Unusual Weld Failures of Rotary Compressor during Hydraulic Tests: Analysis revealed Boron Induced Cracking in Fusion Zone

Authors: Kaushal Kishore, Vaibhav Jain, Hrishikesh Jugade, Saurabh Hadas, Manashi Adhikary, Goutam Mukhopadhyay, Sandip Bhattacharyya

Abstract:

Rotary air compressors in air conditioners are used to suck excessive volume of air from the atmosphere in a small space to provide drive to the components attached to them. Hydraulic test is one of the most important methods to decide the suitability of these components for usage. In the present application, projection welding is used to join the hot rolled steel sheets after forming for manufacturing of air compressors. These sheets belong to two different high strength low alloy (HSLA) steel grades. It was observed that one batch of compressors made of a particular grade was cracking from the weld, whereas those made of another grade were passing the hydraulic tests. Cracking was repeatedly observed from the weld location. A detailed comparative study of the compressors which failed and successfully passed pressure tests has been presented. Location of crack initiation was identified to be the interface of fusion zone/heat affected zone. Shear dimples were observed on the fracture surface confirming the ductile mode of failure. Hardness profile across the weld revealed a sharp rise in hardness in the fusion zone. This was attributed to the presence of untempered martensitic lath in the fusion zone. A sharp metallurgical notch existed at the heat affected zone/fusion zone interface due to transition in microstructure from acicular ferrite and bainite in HAZ to untempered martensite in the fusion zone. In contrast, welds which did not fail during the pressure tests showed a smooth hardness profile with no abnormal rise in hardness in the fusion zone. The bainitic microstructure was observed in the fusion zone of successful welds. This difference in microstructural constituents in the fusion zone was attributed to the presence of a small amount of boron (0.002 wt. %) in the sheets which were cracking. Trace amount of boron is known to substantially increase the hardenability of HSLA steel, and cooling rate during resolidification in the fusion zone is sufficient to form martensite. Post-weld heat treatment was recommended to transform untempered martensite to tempered martensite with lower hardness.

Keywords: compressor, cracking, martensite, weld, boron, hardenability, high strength low alloy steel

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15203 Direct Displacement-Based Design Procedure for Performance-Based Seismic Design of Structures

Authors: Haleh Hamidpour

Abstract:

Since the seismic damageability of structures is controlled by the inelastic deformation capacities of structural elements, seismic design of structure based on force analogy methods is not appropriate. In recent year, the basic approach of design codes have been changed from force-based approach to displacement-based. In this regard, a Direct Displacement-Based Design (DDBD) and a Performance-Based Plastic Design (PBPD) method are proposed. In this study, the efficiency of these two methods on seismic performance of structures is evaluated through a sample 12-story reinforced concrete moment frame. The building is designed separately based on the DDBD and the PBPD methods. Once again the structure is designed by the traditional force analogy method according to the FEMA P695 regulation. Different design method results in different structural elements. Seismic performance of these three structures is evaluated through nonlinear static and nonlinear dynamic analysis. The results show that the displacement-based design methods accommodate the intended performance objectives better than the traditional force analogy method.

Keywords: direct performance-based design, ductility demands, inelastic seismic performance, yield mechanism

Procedia PDF Downloads 333
15202 Corrosion of Concrete Reinforcing Steel Bars Tested and Compared Between Various Protection Methods

Authors: P. van Tonder, U. Bagdadi, B. M. D. Lario, Z. Masina, T. R. Motshwari

Abstract:

This paper analyses how concrete reinforcing steel bars corrode and how it can be minimised through the use of various protection methods against corrosion, such as metal-based paint, alloying, cathodic protection and electroplating. Samples of carbon steel bars were protected, using these four methods. Tests performed on the samples included durability, electrical resistivity and bond strength. Durability results indicated relatively low corrosion rates for alloying, cathodic protection, electroplating and metal-based paint. The resistivity results indicate all samples experienced a downward trend, despite erratic fluctuations in the data, indicating an inverse relationship between electrical resistivity and corrosion rate. The results indicated lowered bond strengths when the reinforced concrete was cured in seawater compared to being cured in normal water. It also showed that higher design compressive strengths lead to higher bond strengths which can be used to compensate for the loss of bond strength due to corrosion in a real-world application. In terms of implications, all protection methods have the potential to be effective at resisting corrosion in real-world applications, especially the alloying, cathodic protection and electroplating methods. The metal-based paint underperformed by comparison, most likely due to the nature of paint in general which can fade and chip away, revealing the steel samples and exposing them to corrosion. For alloying, stainless steel is the suggested material of choice, where Y-bars are highly recommended as smooth bars have a much-lowered bond strength. Cathodic protection performed the best of all in protecting the sample from corrosion, however, its real-world application would require significant evaluation into the feasibility of such a method.

Keywords: protection methods, corrosion, concrete, reinforcing steel bars

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15201 Mentor and Mentee Based Learning

Authors: Erhan Eroğlu

Abstract:

This paper presents a new method called Mentor and Mentee Based Learning. This new method is becoming more and more common especially at workplaces. This study is significant as it clearly underlines how it works well. Education has always aimed at equipping people with the necessary knowledge and information. For many decades it went on teachers’ talk and chalk methods. In the second half of the nineteenth century educators felt the need for some changes in delivery systems. Some new terms like self- discovery, learner engagement, student centered learning, hands on learning have become more and more popular for such a long time. However, some educators believe that there is much room for better learning methods in many fields as they think the learners still cannot fulfill their potential capacities. Thus, new systems and methods are still being developed and applied at education centers and work places. One of the latest methods is assigning some mentors for the newly recruited employees and training them within a mentor and mentee program which allows both parties to see their strengths and weaknesses and the areas which can be improved. This paper aims at finding out the perceptions of the mentors and mentees on the programs they are offered at their workplaces and suggests some betterment alternatives. The study has been conducted via a qualitative method whereby some interviews have been done with both mentors and mentees separately and together. Results show that it is a great way to train inexperienced one and also to refresh the older ones. Some points to be improved have also been underlined. The paper shows that education is not a one way path to follow.

Keywords: learning, mentor, mentee, training

Procedia PDF Downloads 228
15200 Review of Research on Effectiveness Evaluation of Technology Innovation Policy

Authors: Xue Wang, Li-Wei Fan

Abstract:

The technology innovation has become the driving force of social and economic development and transformation. The guidance and support of public policies is an important condition to promote the realization of technology innovation goals. Policy effectiveness evaluation is instructive in policy learning and adjustment. This paper reviews existing studies and systematically evaluates the effectiveness of policy-driven technological innovation. We used 167 articles from WOS and CNKI databases as samples to clarify the measurement of technological innovation indicators and analyze the classification and application of policy evaluation methods. In general, technology innovation input and technological output are the two main aspects of technological innovation index design, among which technological patents are the focus of research, the number of patents reflects the scale of technological innovation, and the quality of patents reflects the value of innovation from multiple aspects. As for policy evaluation methods, statistical analysis methods are applied to the formulation, selection and evaluation of the after-effect of policies to analyze the effect of policy implementation qualitatively and quantitatively. The bibliometric methods are mainly based on the public policy texts, discriminating the inter-government relationship and the multi-dimensional value of the policy. Decision analysis focuses on the establishment and measurement of the comprehensive evaluation index system of public policy. The economic analysis methods focus on the performance and output of technological innovation to test the policy effect. Finally, this paper puts forward the prospect of the future research direction.

Keywords: technology innovation, index, policy effectiveness, evaluation of policy, bibliometric analysis

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15199 Type–2 Fuzzy Programming for Optimizing the Heat Rate of an Industrial Gas Turbine via Absorption Chiller Technology

Authors: T. Ganesan, M. S. Aris, I. Elamvazuthi, Momen Kamal Tageldeen

Abstract:

Terms set in power purchase agreements (PPA) challenge power utility companies in balancing between the returns (from maximizing power production) and securing long term supply contracts at capped production. The production limitation set in the PPA has driven efforts to maximize profits through efficient and economic power production. In this paper, a combined industrial-scale gas turbine (GT) - absorption chiller (AC) system is considered to cool the GT air intake for reducing the plant’s heat rate (HR). This GT-AC system is optimized while considering power output limitations imposed by the PPA. In addition, the proposed formulation accounts for uncertainties in the ambient temperature using Type-2 fuzzy programming. Using the enhanced chaotic differential evolution (CEDE), the Pareto frontier was constructed and the optimization results are analyzed in detail.

Keywords: absorption chillers (AC), turbine inlet air cooling (TIC), power purchase agreement (PPA), multiobjective optimization, type-2 fuzzy programming, chaotic differential evolution (CDDE)

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15198 On the Solution of Fractional-Order Dynamical Systems Endowed with Block Hybrid Methods

Authors: Kizito Ugochukwu Nwajeri

Abstract:

This paper presents a distinct approach to solving fractional dynamical systems using hybrid block methods (HBMs). Fractional calculus extends the concept of derivatives and integrals to non-integer orders and finds increasing application in fields such as physics, engineering, and finance. However, traditional numerical techniques often struggle to accurately capture the complex behaviors exhibited by these systems. To address this challenge, we develop HBMs that integrate single-step and multi-step methods, enabling the simultaneous computation of multiple solution points while maintaining high accuracy. Our approach employs polynomial interpolation and collocation techniques to derive a system of equations that effectively models the dynamics of fractional systems. We also directly incorporate boundary and initial conditions into the formulation, enhancing the stability and convergence properties of the numerical solution. An adaptive step-size mechanism is introduced to optimize performance based on the local behavior of the solution. Extensive numerical simulations are conducted to evaluate the proposed methods, demonstrating significant improvements in accuracy and efficiency compared to traditional numerical approaches. The results indicate that our hybrid block methods are robust and versatile, making them suitable for a wide range of applications involving fractional dynamical systems. This work contributes to the existing literature by providing an effective numerical framework for analyzing complex behaviors in fractional systems, thereby opening new avenues for research and practical implementation across various disciplines.

Keywords: fractional calculus, numerical simulation, stability and convergence, Adaptive step-size mechanism, collocation methods

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15197 Searching the Relationship among Components that Contribute to Interactive Plight and Educational Execution

Authors: Shri Krishna Mishra

Abstract:

In an educational context, technology can prompt interactive plight only when it is used in conjunction with interactive plight methods. This study, therefore, examines the relationships among components that contribute to higher levels of interactive plight and execution, such as interactive Plight methods, technology, intrinsic motivation and deep learning. 526 students participated in this study. With structural equation modelling, the authors test the conceptual model and identify satisfactory model fit. The results indicate that interactive Plight methods, technology and intrinsic motivation have significant relationship with interactive Plight; deep learning mediates the relationships of the other variables with Execution.

Keywords: searching the relationship among components, contribute to interactive plight, educational execution, intrinsic motivation

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15196 Compact, Lightweight, Low Cost, Rectangular Core Power Transformers

Authors: Abidin Tortum, Kubra Kocabey

Abstract:

One of the sectors where the competition is experienced at the highest level in the world is the transformer sector, and sales can be made with a limited profit margin. For this reason, manufacturers must develop cost-cutting designs to achieve higher profits. The use of rectangular cores and coils in transformer design is one of the methods that can be used to reduce costs. According to the best knowledge we have obtained, we think that we are the first company producing rectangular core power transformers in our country. BETA, to reduce the cost of this project, more compact products to reveal, as we know it to increase the alleviate and competitiveness of the product, will perform cored coil design and production rectangle for the first-time power transformers in Turkey. The transformer to be designed shall be 16 MVA, 33/11 kV voltage level. With the rectangular design of the transformer core and windings, no-load losses can be reduced. Also, the least costly transformer type is rectangular. However, short-circuit forces on rectangular windings do not affect every point of the windings in the same way. Whereas more force is applied inwards to the mid-points of the low-voltage winding, the opposite occurs in the high-voltage winding. Therefore, the windings tend to deteriorate in the event of a short circuit. While trying to reach the project objectives, the difficulties in the design should be overcome. Rectangular core transformers to be produced in our country offer a more compact structure than conventional transformers. In other words, both height and width were smaller. Thus, the reducer takes up less space in the center. Because the transformer boiler is smaller, less oil is used, and its weight is lower. Biotemp natural ester fluid is used in rectangular transformer and the cooling performance of this oil is analyzed. The cost was also reduced with the reduction of dimensions. The decrease in the amount of oil used has also increased the environmental friendliness of the developed product. Transportation costs have been reduced by reducing the total weight. The amount of carbon emissions generated during the transportation process is reduced. Since the low-voltage winding is wound with a foil winding technique, a more resistant structure is obtained against short circuit forces. No-load losses were lower due to the use of a rectangular core. The project was handled in three phases. In the first stage, preliminary research and designs were carried out. In the second stage, the prototype manufacturing of the transformer whose designs have been completed has been started. The prototype developed in the last stage has been subjected to routine, type and special tests.

Keywords: rectangular core, power transformer, transformer, productivity

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15195 Air Flow Characteristics and Pressure Distributions for Staggered Wing Shaped Tubes Bundle

Authors: Sayed A. Elsayed, Emad Z. Ibrahim, Osama M. Mesalhy, Mohamed A. Abdelatief

Abstract:

An experimental and numerical study has been conducted to clarify fluid flow characteristics and pressure drop distributions of a cross-flow heat exchanger employing staggered wing-shaped tubes at different angels of attack. The water-side Rew and the air-side Rea were at 5 x 102 and at from 1.8 x 103 to 9.7 x 103, respectively. Three cases of the tubes arrangements with various angles of attack, row angles of attack and 90° cone angles were employed at the considered Rea range. Correlation of pressure drop coefficient Pdc in terms of Rea, design parameters for the studied cases were presented. The flow pattern around the staggered wing-shaped tubes bundle were predicted by using commercial CFD FLUENT 6.3.26 software package. Results indicated that the values of Pdc were increased by increasing the angle of attack from 0° to 45°, while the opposite was true for angles of attack from 135° to 180°. Comparisons between the experimental and numerical results of the present study and those, previously, obtained for similar available studies showed good agreements.

Keywords: wing-shaped tubes, cross-flow cooling, staggered arrangement, CFD

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15194 A Study of Quality Assurance and Unit Verification Methods in Safety Critical Environment

Authors: Miklos Taliga

Abstract:

In the present case study we examined the development and testing methods of systems that contain safety-critical elements in different industrial fields. Consequentially, we observed the classical object-oriented development and testing environment, as both medical technology and automobile industry approaches the development of safety critical elements that way. Subsequently, we examined model-based development. We introduce the quality parameters that define development and testing. While taking modern agile methodology (scrum) into consideration, we examined whether and to what extent the methodologies we found fit into this environment.

Keywords: safety-critical elements, quality managent, unit verification, model base testing, agile methods, scrum, metamodel, object-oriented programming, field specific modelling, sprint, user story, UML Standard

Procedia PDF Downloads 585
15193 Cooperative Coevolution for Neuro-Evolution of Feed Forward Networks for Time Series Prediction Using Hidden Neuron Connections

Authors: Ravneil Nand

Abstract:

Cooperative coevolution uses problem decomposition methods to solve a larger problem. The problem decomposition deals with breaking down the larger problem into a number of smaller sub-problems depending on their method. Different problem decomposition methods have their own strengths and limitations depending on the neural network used and application problem. In this paper we are introducing a new problem decomposition method known as Hidden-Neuron Level Decomposition (HNL). The HNL method is competing with established problem decomposition method in time series prediction. The results show that the proposed approach has improved the results in some benchmark data sets when compared to the standalone method and has competitive results when compared to methods from literature.

Keywords: cooperative coevaluation, feed forward network, problem decomposition, neuron, synapse

Procedia PDF Downloads 335
15192 Mariculture Trials of the Philippine Blue Sponge Xestospongia sp.

Authors: Clairecynth Yu, Geminne Manzano

Abstract:

The mariculture potential of the Philippine blue sponge, Xestospongia sp. was assessed through the pilot sponge culture in the open-sea at two different biogeographic regions in the Philippines. Thirty explants were randomly allocated for the Puerto Galera, Oriental Mindoro culture setup and the other nine were transported to Lucero, Bolinao, Pangasinan. Two different sponge culture methods of the sponge explants- the lantern and the wall method, were employed to assess the production of the Renieramycin M. Both methods have shown to be effective in growing the sponge explants and that the Thin Layer Chromatography (TLC) results have shown that Renieramycin M is present on the sponges. The effect of partial harvesting in the growth and survival rates of the blue sponge in the Puerto Galera setup was also determined. Results showed that a higher growth rate was observed on the partially harvested explants on both culture methods as compared to the unharvested explants.

Keywords: chemical ecology, porifera, sponge, Xestospongia sp.

Procedia PDF Downloads 273
15191 Framework for Integrating Big Data and Thick Data: Understanding Customers Better

Authors: Nikita Valluri, Vatcharaporn Esichaikul

Abstract:

With the popularity of data-driven decision making on the rise, this study focuses on providing an alternative outlook towards the process of decision-making. Combining quantitative and qualitative methods rooted in the social sciences, an integrated framework is presented with a focus on delivering a much more robust and efficient approach towards the concept of data-driven decision-making with respect to not only Big data but also 'Thick data', a new form of qualitative data. In support of this, an example from the retail sector has been illustrated where the framework is put into action to yield insights and leverage business intelligence. An interpretive approach to analyze findings from both kinds of quantitative and qualitative data has been used to glean insights. Using traditional Point-of-sale data as well as an understanding of customer psychographics and preferences, techniques of data mining along with qualitative methods (such as grounded theory, ethnomethodology, etc.) are applied. This study’s final goal is to establish the framework as a basis for providing a holistic solution encompassing both the Big and Thick aspects of any business need. The proposed framework is a modified enhancement in lieu of traditional data-driven decision-making approach, which is mainly dependent on quantitative data for decision-making.

Keywords: big data, customer behavior, customer experience, data mining, qualitative methods, quantitative methods, thick data

Procedia PDF Downloads 162
15190 Comparison of Different Extraction Methods for the Determination of Polyphenols

Authors: Senem Suna

Abstract:

Extraction of bioactive compounds from several food/food products comes as an important topic and new trend related with health promoting effects. As a result of the increasing interest in natural foods, different methods are used for the acquisition of these components especially polyphenols. However, special attention has to be paid to the selection of proper techniques or several processing technologies (supercritical fluid extraction, microwave-assisted extraction, ultrasound-assisted extraction, powdered extracts production) for each kind of food to get maximum benefit as well as the obtainment of phenolic compounds. In order to meet consumer’s demand for healthy food and the management of quality and safety requirements, advanced research and development are needed. In this review, advantages, and disadvantages of different extraction methods, their opportunities to be used in food industry and the effects of polyphenols are mentioned in details. Consequently, with the evaluation of the results of several studies, the selection of the most suitable food specific method was aimed.

Keywords: bioactives, extraction, powdered extracts, supercritical fluid extraction

Procedia PDF Downloads 239
15189 One Dimensional Unsteady Boundary Layer Flow in an Inclined Wavy Wall of a Nanofluid with Convective Boundary Condition

Authors: Abdulhakeem Yusuf, Yomi Monday Aiyesimi, Mohammed Jiya

Abstract:

The failure in an ordinary heat transfer fluid to meet up with today’s industrial cooling rate has resulted in the development of high thermal conductivity fluid which nanofluids belongs. In this work, the problem of unsteady one dimensional laminar flow of an incompressible fluid within a parallel wall is considered with one wall assumed to be wavy. The model is presented in its rectangular coordinate system and incorporates the effects of thermophoresis and Brownian motion. The local similarity solutions were also obtained which depends on Soret number, Dufour number, Biot number, Lewis number, and heat generation parameter. The analytical solution is obtained in a closed form via the Adomian decomposition method. It was found that the method has a good agreement with the numerical method, and it is also established that the heat generation parameter has to be kept low so that heat energy are easily evacuated from the system.

Keywords: Adomian decomposition method, Biot number, Dufour number, nanofluid

Procedia PDF Downloads 329