Search results for: power block
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7232

Search results for: power block

4892 The Usage of Bridge Estimator for Hegy Seasonal Unit Root Tests

Authors: Huseyin Guler, Cigdem Kosar

Abstract:

The aim of this study is to propose Bridge estimator for seasonal unit root tests. Seasonality is an important factor for many economic time series. Some variables may contain seasonal patterns and forecasts that ignore important seasonal patterns have a high variance. Therefore, it is very important to eliminate seasonality for seasonal macroeconomic data. There are some methods to eliminate the impacts of seasonality in time series. One of them is filtering the data. However, this method leads to undesired consequences in unit root tests, especially if the data is generated by a stochastic seasonal process. Another method to eliminate seasonality is using seasonal dummy variables. Some seasonal patterns may result from stationary seasonal processes, which are modelled using seasonal dummies but if there is a varying and changing seasonal pattern over time, so the seasonal process is non-stationary, deterministic seasonal dummies are inadequate to capture the seasonal process. It is not suitable to use seasonal dummies for modeling such seasonally nonstationary series. Instead of that, it is necessary to take seasonal difference if there are seasonal unit roots in the series. Different alternative methods are proposed in the literature to test seasonal unit roots, such as Dickey, Hazsa, Fuller (DHF) and Hylleberg, Engle, Granger, Yoo (HEGY) tests. HEGY test can be also used to test the seasonal unit root in different frequencies (monthly, quarterly, and semiannual). Another issue in unit root tests is the lag selection. Lagged dependent variables are added to the model in seasonal unit root tests as in the unit root tests to overcome the autocorrelation problem. In this case, it is necessary to choose the lag length and determine any deterministic components (i.e., a constant and trend) first, and then use the proper model to test for seasonal unit roots. However, this two-step procedure might lead size distortions and lack of power in seasonal unit root tests. Recent studies show that Bridge estimators are good in selecting optimal lag length while differentiating nonstationary versus stationary models for nonseasonal data. The advantage of this estimator is the elimination of the two-step nature of conventional unit root tests and this leads a gain in size and power. In this paper, the Bridge estimator is proposed to test seasonal unit roots in a HEGY model. A Monte-Carlo experiment is done to determine the efficiency of this approach and compare the size and power of this method with HEGY test. Since Bridge estimator performs well in model selection, our approach may lead to some gain in terms of size and power over HEGY test.

Keywords: bridge estimators, HEGY test, model selection, seasonal unit root

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4891 The Evolution of Online Hate: How Decades of Tactical and Technological Innovation Created a Hate Epidemic

Authors: Kashvi Jain, Adam Burston

Abstract:

Right-wing social movements are a dominant force in American politics, as evidenced by the January 6th Insurrection, the prevalence of extremist conspiracy theories, and a nationwide surge in hate crime. Despite an abundance of scholarship on contemporary right-wing extremism, there is little scholarship that explains their rise. This paper examines how the white power movement developed through tactical innovation and strategic use of increasingly powerful digital technologies. Using qualitative content analysis of archived digital bulletin boards and websites, we examine right-wing extremists’ digital communication during three consequential time periods of tactical and technological innovation: pre-internet (1980s), web 1.0 (1990s), and web 2.0 (2000s). Our analysis suggests that right-wing activists innovatively exploited the features and affordances of digital technologies and their knowledge of free speech rights to spread supremacist collective identity and ideology. Beyond our empirical contribution, we offer policy advice that school administrators can employ to limit hate.

Keywords: leaderless resistance, technological affordances, anti-defamation league, white power movement, tactical

Procedia PDF Downloads 69
4890 Modified Bat Algorithm for Economic Load Dispatch Problem

Authors: Daljinder Singh, J.S.Dhillon, Balraj Singh

Abstract:

According to no free lunch theorem, a single search technique cannot perform best in all conditions. Optimization method can be attractive choice to solve optimization problem that may have exclusive advantages like robust and reliable performance, global search capability, little information requirement, ease of implementation, parallelism, no requirement of differentiable and continuous objective function. In order to synergize between exploration and exploitation and to further enhance the performance of Bat algorithm, the paper proposed a modified bat algorithm that adds additional search procedure based on bat’s previous experience. The proposed algorithm is used for solving the economic load dispatch (ELD) problem. The practical constraint such valve-point loading along with power balance constraints and generator limit are undertaken. To take care of power demand constraint variable elimination method is exploited. The proposed algorithm is tested on various ELD problems. The results obtained show that the proposed algorithm is capable of performing better in majority of ELD problems considered and is at par with existing algorithms for some of problems.

Keywords: bat algorithm, economic load dispatch, penalty method, variable elimination method

Procedia PDF Downloads 459
4889 The Nation as Brand: Postcolonial Construction of National Identity in Late 20th/21st Century Qatar

Authors: Ryunhye Kim

Abstract:

Despite its relatively short history as an independent state, Qatar has emerged as a highly regarded Gulf state and global power. Since its independence in September 1971, the state has employed deliberate policy initiatives designed to put Qatar on the map and distinguish it from other Gulf states. Because Qatar and its neighbors are resource-poor apart from energy, whoever is first to introduce a unique aspect of branding not only takes the lead but assumes what is often an insurmountable advantage. This study examines three specific modes of branding undertaken by Qatar: (1) energy policies to utilize its natural gas to become a dominant supplier; (2) the deliberate construction of a distinct cultural brand utilizing sports, architecture, museums, and media; and (3) ‘niche diplomacy’ to serve as a mediator in regional and intra-national conflicts, especially as interlocutor between the United States and Arab regimes and Muslim groups. Gleaning data from a range of sources, this study analyzes the effectiveness and significance of Qatar’s place branding on the global stage, as well as potential disadvantages and limits in this branding, including problems encountered before and after the ‘Qatar crisis.’

Keywords: national branding, national-identity, Qatar, soft-power

Procedia PDF Downloads 152
4888 Effect of Slag Application to Soil Chemical Properties and Rice Yield on Acid Sulphate Soils with Different Pyrite Depth

Authors: Richardo Y. E. Sihotang, Atang Sutandi, Joshua Ginting

Abstract:

The expansion of marginal soil such as acid sulphate soils for the development of staple crops, including rice was unavoidable. However, acid sulphate soils were less suitable for rice field due to the low fertility and the threats of pyrite oxidation. An experiment using Randomized Complete Block Design was designed to investigate the effect of slag in stabilizing soil reaction (pH), improving soil fertility and rice yield. Experiments were conducted in two locations with different pyrite depth. The results showed that slag application was able to decrease the exchangeable Al and available iron (Fe) as well as increase the soil pH, available-P, soil exchangeable Ca2+, Mg2+, and K+. Furthermore, the slag application increased the plant nutrient uptakes, particularly N, P, K, followed by the increasing of rice yield significantly. Nutrients availability, nutrient uptake, and rice yield were higher in the shallow pyrite soil instead of the deep pyrite soil. In addition, slag application was economically feasible due to the ability to reduce standard fertilizer requirements.

Keywords: acid sulphate soils, available nutrients, pyrite, slag

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4887 Development of Adaptive Proportional-Integral-Derivative Feeding Mechanism for Robotic Additive Manufacturing System

Authors: Andy Alubaidy

Abstract:

In this work, a robotic additive manufacturing system (RAMS) that is capable of three-dimensional (3D) printing in six degrees of freedom (DOF) with very high accuracy and virtually on any surface has been designed and built. One of the major shortcomings in existing 3D printer technology is the limitation to three DOF, which results in prolonged fabrication time. Depending on the techniques used, it usually takes at least two hours to print small objects and several hours for larger objects. Another drawback is the size of the printed objects, which is constrained by the physical dimensions of most low-cost 3D printers, which are typically small. In such cases, large objects are produced by dividing them into smaller components that fit the printer’s workable area. They are then glued, bonded or otherwise attached to create the required object. Another shortcoming is material constraints and the need to fabricate a single part using different materials. With the flexibility of a six-DOF robot, the RAMS has been designed to overcome these problems. A feeding mechanism using an adaptive Proportional-Integral-Derivative (PID) controller is utilized along with a national instrument compactRIO (NI cRIO), an ABB robot, and off-the-shelf sensors. The RAMS have the ability to 3D print virtually anywhere in six degrees of freedom with very high accuracy. It is equipped with an ABB IRB 120 robot to achieve this level of accuracy. In order to convert computer-aided design (CAD) files to digital format that is acceptable to the robot, Hypertherm Robotic Software Inc.’s state-of-the-art slicing software called “ADDMAN” is used. ADDMAN is capable of converting any CAD file into RAPID code (the programing language for ABB robots). The robot uses the generated code to perform the 3D printing. To control the entire process, National Instrument (NI) compactRIO (cRio 9074), is connected and communicated with the robot and a feeding mechanism that is designed and fabricated. The feeding mechanism consists of two major parts, cold-end and hot-end. The cold-end consists of what is conventionally known as an extruder. Typically, a stepper-motor is used to control the push on the material, however, for optimum control, a DC motor is used instead. The hot-end consists of a melt-zone, nozzle, and heat-brake. The melt zone ensures a thorough melting effect and consistent output from the nozzle. Nozzles are made of brass for thermo-conductivity while the melt-zone is comprised of a heating block and a ceramic heating cartridge to transfer heat to the block. The heat-brake ensures that there is no heat creep-up effect as this would swell the material and prevent consistent extrusion. A control system embedded in the cRio is developed using NI Labview which utilizes adaptive PID to govern the heating cartridge in conjunction with a thermistor. The thermistor sends temperature feedback to the cRio, which will issue heat increase or decrease based on the system output. Since different materials have different melting points, our system will allow us to adjust the temperature and vary the material.

Keywords: robotic, additive manufacturing, PID controller, cRIO, 3D printing

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4886 Investigating the Effect of Height on Essential Oils of Urtica diocia L.: Case Study of Ramsar, Mazandaran, Iran

Authors: Keivan Saeb, Azade Kakouei, Razieh Jafari Hajati, Khalil Pourshamsian, Babak Babakhani

Abstract:

Urtica Diocia L. from the Urticaceae family is a plant of herbal value and of a noticeable distribution in the north of Iran. The growth of different plants in various natural environments and ecosystems seems to be affected by factors such as the height (from sea surface).To investigate the effect of height on Urtica Diocia L. medicine compounds in its natural environment, three areas with the height of zero, 800 and 1800m were selected.The samples were randomly gathered three times and were dried; also, their compounds was extracted using the Clivenger with the water-distilling method. To determine the medicine compounds, the GC-MS as well as the GC machines were used. The analysis of variance was done in the form of the random-full-block design. The results indicated that there was a significant difference between the percent of EOs in the selected heights; however, such difference was not significant within each height. From among the eight flavors of the study, the phytol compound was more in terms of percentage. By increasing the height the percent of EOs would decrease. lower heights could be considered most appropriate for producing the studied effective materials despite of the moistened climate and soil there.

Keywords: Urtica diocia L., height, EOs, medicine

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4885 Study for an Optimal Cable Connection within an Inner Grid of an Offshore Wind Farm

Authors: Je-Seok Shin, Wook-Won Kim, Jin-O Kim

Abstract:

The offshore wind farm needs to be designed carefully considering economics and reliability aspects. There are many decision-making problems for designing entire offshore wind farm, this paper focuses on an inner grid layout which means the connection between wind turbines as well as between wind turbines and an offshore substation. A methodology proposed in this paper determines the connections and the cable type for each connection section using K-clustering, minimum spanning tree and cable selection algorithms. And then, a cost evaluation is performed in terms of investment, power loss and reliability. Through the cost evaluation, an optimal layout of inner grid is determined so as to have the lowest total cost. In order to demonstrate the validity of the methodology, the case study is conducted on 240MW offshore wind farm, and the results show that it is helpful to design optimally offshore wind farm.

Keywords: offshore wind farm, optimal layout, k-clustering algorithm, minimum spanning algorithm, cable type selection, power loss cost, reliability cost

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4884 Investigation of Green Dye-Sensitized Solar Cells Based on Natural Dyes

Authors: M. Hosseinnezhad, K. Gharanjig

Abstract:

Natural dyes, extracted from black carrot and bramble, were utilized as photosensitizers to prepare dye-sensitized solar cells (DSSCs). Spectrophotometric studies of the natural dyes in solution and on a titanium dioxide substrate were carried out in order to assess changes in the status of the dyes. The results show that the bathochromic shift is seen on the photo-electrode substrate. The chemical binding of the natural dyes at the surface photo-electrode were increased by the chelating effect of the Ti(IV) ions. The cyclic voltammetry results showed that all extracts are suitable to be performed in DSSCs. Finally, photochemical performance and stability of DSSCs based on natural dyes were studied. The DSSCs sensitized by black carrot extract have been reported to achieve up to Jsc=1.17 mAcm-2, Voc= 0.55 V, FF= 0.52, η=0.34%, whereas Bramble extract can obtain up to Jsc=2.24 mAcm-2, Voc= 0.54 V, FF= 0.57, η=0.71%. The power conversion efficiency was obtained from the mixed dyes in DSSCs. The power conversion efficiency of dye-sensitized solar cells using mixed Black carrot and Bramble dye is the average of the their efficiency in single DSSCs.

Keywords: anthocyanin, dye-sensitized solar cells, green energy, optical materials

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4883 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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4882 Enforcement of Decisions of Ombudsmen and the South African Public Protector: Muzzling the Watchdogs

Authors: Roxan Venter

Abstract:

Ombudsmen often face the challenge of a lack of authority to have their decisions and recommendations enforced. This lack of authority may be seen as one of the major obstacles in the way of the effectiveness of the institutions of Ombudsman and also the South African Public Protector. The paper will address the current legal position in South Africa with regard to the status of the decisions and recommendations of the South African Public Protector and the enforcement thereof. In addition, the paper will compare the South African position with the experiences of other jurisdictions, including Scandinavian countries like Sweden, Denmark and Norway, but also New Zealand and Northern Ireland, with regard to the enforcement of the decisions of Ombudsmen. Finally, the paper will make recommendations with regard to the enhancement of the power and authority of Ombudsmen in order to effectively enforce their decisions. It is submitted that the creation of the office of Ombudsman, and the Public Protector in the South African system, is an essential tool to ensure the protection of society against governmental abuse of power and it is therefore imperative to ensure that these watchdogs of democracy are not muzzled by a lack of powers of enforcement.

Keywords: enforcement of decisions of ombudsmen, governmental control, ombudsman, South African public protector

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4881 Wind Comfort and Safety of People in the Vicinity of Tall Buildings

Authors: Mohan Kotamrazu

Abstract:

Tall buildings block and divert strong upper level winds to the ground. These high velocity winds many a time create adverse wind effects at ground level which can be uncomfortable and even compromise the safety of pedestrians and people who frequent the spaces in the vicinity of tall buildings. Discomfort can be experienced around the entrances and corners of tall buildings. Activities such as strolling or sitting in a park, waiting for a bus near a tall building can become highly unpleasant. For the elderly unpleasant conditions can also become dangerous leading to accidents and injuries. Today there is a growing concern among architects, planners and urban designers about the wind environment in the vicinity of tall building. Regulating authorities insist on wind tunnel testing of tall buildings in cities such as Wellington, Auckland, Boston, San Francisco, etc. prior to granting permission for their construction The present paper examines the different ways that tall buildings can induce strong winds at pedestrian level and their impact on people who frequent the spaces around tall buildings.

Keywords: tall buildings, wind effects, wind comfort, wind safety

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4880 Effects of Directivity and Fling Step on Buildings Equipped with J-Hook Sandwich Composite Walls and Reinforced Concrete Shear Walls

Authors: Majid Saaly, Shahriar Tavousi Tafreshi, Mehdi Nazari Afshar

Abstract:

The structural systems with the sandwich composite wall (SCSSC) are of very popular due to their ductileness and competency to swallow more energy and power than standard reinforced concrete shear walls. The purpose of this enhanced system is in high-rise building, Nuclear power plant facilities, and bridge slabs are much more. SCSSCs showed acceptable seismic performance under experimental tests and cyclic loading from the points of view of in-plane and out-of-plane shear and flexural interaction, in-plane punching shear, and compressive behavior. The use of sandwich composite walls with J-hook connectors has a significant effect on energy dissipation and reduction of dynamic responses of mid-rise and high-rise structural models. By changing the systems of the building from SW to SCWJ, the maximum inter-story drift values of ten- and fifteen-story models are reduced by up to 25% and 35%, respectively.

Keywords: J-Hook sandwich composite walls, fling step, directivity, IDA analyses, fractile curves

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4879 Internal Methane Dry Reforming Kinetic Models in Solid Oxide Fuel Cells

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

Abstract:

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

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

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4878 Named Entity Recognition System for Tigrinya Language

Authors: Sham Kidane, Fitsum Gaim, Ibrahim Abdella, Sirak Asmerom, Yoel Ghebrihiwot, Simon Mulugeta, Natnael Ambassager

Abstract:

The lack of annotated datasets is a bottleneck to the progress of NLP in low-resourced languages. The work presented here consists of large-scale annotated datasets and models for the named entity recognition (NER) system for the Tigrinya language. Our manually constructed corpus comprises over 340K words tagged for NER, with over 118K of the tokens also having parts-of-speech (POS) tags, annotated with 12 distinct classes of entities, represented using several types of tagging schemes. We conducted extensive experiments covering convolutional neural networks and transformer models; the highest performance achieved is 88.8% weighted F1-score. These results are especially noteworthy given the unique challenges posed by Tigrinya’s distinct grammatical structure and complex word morphologies. The system can be an essential building block for the advancement of NLP systems in Tigrinya and other related low-resourced languages and serve as a bridge for cross-referencing against higher-resourced languages.

Keywords: Tigrinya NER corpus, TiBERT, TiRoBERTa, BiLSTM-CRF

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4877 Computer-Based Model for Design Selection of Lightning Arrester for 132/33kV Substation

Authors: Uma U. Uma, Uzoechi Laz

Abstract:

Protection of equipment insulation against lightning over voltages and selection of lightning arrester that will discharge at lower voltage level than the voltage required to breakdown the electrical equipment insulation is examined. The objectives of this paper are to design a computer based model using standard equations for the selection of appropriate lightning arrester with the lowest rated surge arrester that will provide adequate protection of equipment insulation and equally have a satisfactory service life when connected to a specified line voltage in power system network. The effectiveness and non-effectiveness of the earthing system of substation determine arrester properties. MATLAB program with GUI (graphic user interphase) its subprogram is used in the development of the model for the determination of required parameters like voltage rating, impulse spark over voltage, power frequency spark over voltage, discharge current, current rating and protection level of lightning arrester of a specified voltage level of a particular line.

Keywords: lightning arrester, GUIs, MatLab program, computer based model

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4876 A Computational Study of the Effect of Intake Design on Volumetric Efficiency for Best Performance in Motorsport

Authors: Dominic Wentworth-Linton, Shian Gao

Abstract:

This project was aimed at investigating the effect of velocity stacks on the intakes of internal combustion engines for motorsport applications. The intake systems in motorsport are predominantly fuel injection with a plate mounted for the stacks. Using Computational Fluid Dynamics software, the relationship between the stack length and power and torque delivery across the engine’s rev range was investigated and the results were used to choose the best option for its intended motorsport discipline. The test results are expected to vary with engine geometry and its natural manufacturer characteristics. The test was also relevant in bridging between computational data and real simulation as the results show flow, pressure and velocity readings but the behaviour of the engine is inferred from the nature of each test. The results of the data analysis were tested in a real-life simulation on a dynamometer to prove the theory of stack length on power and torque delivery, which helps determine the most suitable stack for the Vauxhall engine for rallying in the Caribbean.

Keywords: CFD simulation, Internal combustion engine, Intake system, Dynamometer test

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4875 Fabrication of Glucose/O₂ Microfluidic Biofuel Cell with Double Layer of Electrodes

Authors: Haroon Khan, Chul Min Kim, Sung Yeol Kim, Sanket Goel, Prabhat K. Dwivedi, Ashutosh Sharma, Gyu Man Kim

Abstract:

Enzymatic biofuel cells (EBFCs) have drawn the attention of researchers due to its demanding application in medical implants. In EBFCs, electricity is produced with the help of redox enzymes. In this study, we report the fabrication of membraneless EBFC with new design of electrodes to overcome microchannel related limitations. The device consists of double layer of electrodes on both sides of Y-shaped microchannel to reduce the effect of oxygen depletion layer and diffusion of fuel and oxidant at the end of microchannel. Moreover, the length of microchannel was reduced by half keeping the same area of multiwalled carbon nanotubes (MWCNT) electrodes. Polydimethylsiloxane (PDMS) stencils were used to pattern MWCNT electrodes on etched Indium Tin Oxide (ITO) glass. PDMS casting was used to fabricate microchannel of the device. Both anode and cathode were modified with glucose oxidase and laccase. Furthermore, these enzymes were covalently bound to carboxyl MWCNTs with the help of EDC/NHS. Glucose used as fuel was oxidized by glucose oxidase at anode while oxygen was reduced to water at the cathode side. The resulted devices were investigated with the help of polarization curves obtained from Chronopotentiometry technique by using potentiostat. From results, we conclude that the performance of double layer EBFC is improved 15 % as compared to single layer EBFC delivering maximum power density of 71.25 µW cm-2 at a cell potential of 0.3 V and current density of 250 µA cm-2 at micro channel height of 450-µm and flow rate of 25 ml hr-1. However, the new device was stable only for three days after which its power output was rapidly dropped by 75 %. This work demonstrates that the power output of membraneless EBFC is improved comparatively, but still efforts will be needed to make the device stable over long period of time.

Keywords: EBFC, glucose, MWCNT, microfluidic

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4874 Beauty Representation and Body Politic of Women Writers in Magdalene

Authors: Putri Alya Ramadhani

Abstract:

This research analysed how women writers represent their beauty in a platform called Magdalene. With the vision “Supporting diversity, empowering minds,” Magdalene is a new media that seeks to represent women's voices rarely heard in mainstream media. This research elaborates further on how women writers, through their writing, use their body politic to subvert patriarchal values. This research used a qualitative method with an explorative design by using text analysis based on the representation theory of Stuart Hall and in-dept-interview with Women Writers in Magdalene. The result illustrated that women writers represent their beauty in Magdalene to subvert body and beauty-representation in mainstream discourse. Furthermore, the authors have identified an identity negotiation as tension from inevitable oppression and power towards and from women’s bodies. In addition, Women Writers showed the power of their bodies through the redefinition of beauty practices and self. Hence, they subvert body dichotomy to redefine body values in society. In conclusion, this study shows various representations of beauty and body that are underrepresented in the mainstream media through the innovative new medium, Magdalena.

Keywords: women writers, beauty-representation, body politic, new media, identity negotiation

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4873 Enhancing Greenhouse Productivity and Energy Efficiency Through UV-IR Reflective Coatings and Dust Mitigation: A Case Study in Saudi Arabia

Authors: Tayirjan Taylor Isimjan, Essam Jamea, Muien Qaryouti

Abstract:

The demand for efficient greenhouse production is escalating, necessitating continuous improvements in controlled plant growth environments. Central to maximizing growth are critical light-related factors, including quantity, quality, and geometric distribution of intercepted radiation. This becomes particularly crucial in regions like the Middle East, characterized by high solar radiation and dusty atmospheric conditions. Existing greenhouse technologies often rely on additional expensive equipment to manage light conditions effectively. In this study, we propose a distinct approach employing functional coatings to mitigate dust and block UV and IR radiation, thereby conserving energy and enhancing productivity. By combining UV-IR reflective coatings with dust mitigation strategies, we aim to address both environmental challenges and energy consumption issues faced by greenhouse agriculture in Saudi Arabia.

Keywords: greenhouse, UV-IR reflective coatings, dust mitigation, energy efficiency, productivity

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4872 Commercial Winding for Superconducting Cables and Magnets

Authors: Glenn Auld Knierim

Abstract:

Automated robotic winding of high-temperature superconductors (HTS) addresses precision, efficiency, and reliability critical to the commercialization of products. Today’s HTS materials are mature and commercially promising but require manufacturing attention. In particular to the exaggerated rectangular cross-section (very thin by very wide), winding precision is critical to address the stress that can crack the fragile ceramic superconductor (SC) layer and destroy the SC properties. Damage potential is highest during peak operations, where winding stress magnifies operational stress. Another challenge is operational parameters such as magnetic field alignment affecting design performance. Winding process performance, including precision, capability for geometric complexity, and efficient repeatability, are required for commercial production of current HTS. Due to winding limitations, current HTS magnets focus on simple pancake configurations. HTS motors, generators, MRI/NMR, fusion, and other projects are awaiting robotic wound solenoid, planar, and spherical magnet configurations. As with conventional power cables, full transposition winding is required for long length alternating current (AC) and pulsed power cables. Robotic production is required for transposition, periodic swapping of cable conductors, and placing into precise positions, which allows power utility required minimized reactance. A full transposition SC cable, in theory, has no transmission length limits for AC and variable transient operation due to no resistance (a problem with conventional cables), negligible reactance (a problem for helical wound HTS cables), and no long length manufacturing issues (a problem with both stamped and twisted stacked HTS cables). The Infinity Physics team is solving manufacturing problems by developing automated manufacturing to produce the first-ever reliable and utility-grade commercial SC cables and magnets. Robotic winding machines combine mechanical and process design, specialized sense and observer, and state-of-the-art optimization and control sequencing to carefully manipulate individual fragile SCs, especially HTS, to shape previously unattainable, complex geometries with electrical geometry equivalent to commercially available conventional conductor devices.

Keywords: automated winding manufacturing, high temperature superconductor, magnet, power cable

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4871 Examining Influence of The Ultrasonic Power and Frequency on Microbubbles Dynamics Using Real-Time Visualization of Synchrotron X-Ray Imaging: Application to Membrane Fouling Control

Authors: Masoume Ehsani, Ning Zhu, Huu Doan, Ali Lohi, Amira Abdelrasoul

Abstract:

Membrane fouling poses severe challenges in membrane-based wastewater treatment applications. Ultrasound (US) has been considered an effective fouling remediation technique in filtration processes. Bubble cavitation in the liquid medium results from the alternating rarefaction and compression cycles during the US irradiation at sufficiently high acoustic pressure. Cavitation microbubbles generated under US irradiation can cause eddy current and turbulent flow within the medium by either oscillating or discharging energy to the system through microbubble explosion. Turbulent flow regime and shear forces created close to the membrane surface cause disturbing the cake layer and dislodging the foulants, which in turn improve the cleaning efficiency and filtration performance. Therefore, the number, size, velocity, and oscillation pattern of the microbubbles created in the liquid medium play a crucial role in foulant detachment and permeate flux recovery. The goal of the current study is to gain in depth understanding of the influence of the US power intensity and frequency on the microbubble dynamics and its characteristics generated under US irradiation. In comparison with other imaging techniques, the synchrotron in-line Phase Contrast Imaging technique at the Canadian Light Source (CLS) allows in-situ observation and real-time visualization of microbubble dynamics. At CLS biomedical imaging and therapy (BMIT) polychromatic beamline, the effective parameters were optimized to enhance the contrast gas/liquid interface for the accuracy of the qualitative and quantitative analysis of bubble cavitation within the system. With the high flux of photons and the high-speed camera, a typical high projection speed was achieved; and each projection of microbubbles in water was captured in 0.5 ms. ImageJ software was used for post-processing the raw images for the detailed quantitative analyses of microbubbles. The imaging has been performed under the US power intensity levels of 50 W, 60 W, and 100 W, in addition to the US frequency levels of 20 kHz, 28 kHz, and 40 kHz. For the duration of 2 seconds of imaging, the effect of the US power and frequency on the average number, size, and fraction of the area occupied by bubbles were analyzed. Microbubbles’ dynamics in terms of their velocity in water was also investigated. For the US power increase of 50 W to 100 W, the average bubble number and the average bubble diameter were increased from 746 to 880 and from 36.7 µm to 48.4 µm, respectively. In terms of the influence of US frequency, a fewer number of bubbles were created at 20 kHz (average of 176 bubbles rather than 808 bubbles at 40 kHz), while the average bubble size was significantly larger than that of 40 kHz (almost seven times). The majority of bubbles were captured close to the membrane surface in the filtration unit. According to the study observations, membrane cleaning efficiency is expected to be improved at higher US power and lower US frequency due to the higher energy release to the system by increasing the number of bubbles or growing their size during oscillation (optimum condition is expected to be at 20 kHz and 100 W).

Keywords: bubble dynamics, cavitational bubbles, membrane fouling, ultrasonic cleaning

Procedia PDF Downloads 149
4870 Practical Guidelines for Utilizing WipFrag Software to Assess Oversize Blast Material Using Both Orthomosaic and Digital Images

Authors: Blessing Olamide Taiwo, Andrew Palangio, Chirag Savaliya, Jenil Patel

Abstract:

Oversized material resulting from blasting presents a notable drawback in the transportation of run-off-mine material due to increased expenses associated with handling, decreased efficiency in loading, and greater wear on digging equipment. Its irregular size and weight demand additional resources and time for secondary breakage, impacting overall productivity and profitability. This paper addresses the limitations of interpreting image analysis software results and applying them to the assessment of blast-generated oversized materials. This comprehensive guide utilizes both ortho mosaic and digital photos to provide critical approaches for optimizing fragmentation analysis and improving decision-making in mining operations. It briefly covers post-blast assessment, blast block heat map interpretation, and material loading decision-making recommendations.

Keywords: blast result assessment, WipFrag, oversize identification, orthomosaic images, production optimization

Procedia PDF Downloads 39
4869 Calculating the Carbon Footprint of Laser Cutting Machines from Cradle to Grave and Examination the Effect of the Use of the Machine on the Carbon Footprint

Authors: Melike Yaylacı, Tuğba Bilgin

Abstract:

Against the climate crisis, an increasing number of countries are working on green energy, carbon emission measurement, calculation and reduction. The work of industrial organizations with the highest carbon emissions on these issues is increasing. Aim of this paper is calculating carbon emissions of laser cutting machine with cradle-to-grave approach and discuss the potential affects of usage condisions, such as laser power, gas type, gas pressure, on carbon footprint. In particular, this study includes consumption of electricity used in production, laser cutting machine raw materials, and disposal of the machine. In the process of raw material supplying, machine procesing and shipping, all calculations were studied using the Tier1 approach. Laser cutting machines require a specified cutting parameter set for each different material in different thickneses, this parameters are a combination of laser power, gas type, cutting speed, gas pressure and focus point, The another purpose of this study is examine the potential affect of different cutting parameters for the same material in same thickness on carbon footprint.

Keywords: life cycle assessment, carbon emission, laser cutting machine, cutting parameters

Procedia PDF Downloads 99
4868 The Psychological and Behavioral Problems of Children of the First Years and Their Interest in School Education

Authors: Amina Salem Attia

Abstract:

This east project consists in studying The child's mental health is the medium through which he expresses his thoughts, so pay attention to it because it is an essential building block in the process of building the child's future personality, where it gives him a balance between feelings and mental thoughts, and since the family is the child's first guardian, it greatly affects his personality and psychological development. As the disturbed environment contributes to behavioral deviations and mental disorders, unlike the stable environment, which plays a major role in developing the child's abilities and forming his psychologically sound attitudes, this should not be forgotten about the role of the school, it is also the second social institution after the family and has a major impact on the child's mental health as it contributes It is important in forming the child's personality and developing his skills and achieving his healthy psychological development, by providing him with psychological care and helping him to solve his problems by using models that are valid for the behavior that is taught to him or that the teachers present in their daily behavior with him.

Keywords: psychological, behavioral problems, children, school education

Procedia PDF Downloads 138
4867 Evaluation of Bollworm Tolerance in F1 and F2 BT Cotton under Unprotected Condition

Authors: N. K. Bhute, B. B. Bhosle

Abstract:

Field experiment was conducted during kharif 2005, at the experimental farm of the Department of Genetics and Plant Breeding, College of Agriculture, Marathwada Agricultural University, Parbhani, Maharashtra. F1 and F2 hybrids of 23 Bt and 5 non-Bt hybrids were grown in a randomized block design with two replications. The results showed that among F1 hybrids, open boll damage due to bollworm complex was not noticed in 4233 Bt and 4247 Bt cotton hybrids which were found significantly superior over MECH 6301 Bt (3.2 %), 4255 Bt (3.28 %) and it was at par with rest of the hybrids. Among F2 hybrids minimum open boll damage (3.10 %) was noticed in Proagro 144 Bt, which was found significantly superior over rest of the hybrids except 4234 Bt (4.17 %) and 4254 Bt (4.98 %) which were at par with each other. In respect of seed cotton yield, among F1 hybrids maximum yield (15.51 q/ha) was recorded in 4233 Bt which was found significantly superior over rest of the hybrids except 4237 Bt (15.24 q/ha). Among F2 maximum yield (15.44 q/ha) was recorded in 4233 Bt which was found significantly superior over rest of the hybrids except 4258 Bt (15.41 q/ha), 4239 Bt (15.098 q/ha) which were at par with each other. Thus F2 Bt cotton express Bt protein in segregated pattern in which bollworm attack was more as compared to F1 which affects yield as well as quality of lint.

Keywords: Bt cotton, bollworms, F1 and F2 generations, unprotected condition

Procedia PDF Downloads 299
4866 Modelling the Photovoltaic Pump Output Using Empirical Data from Local Conditions in the Vhembe District

Authors: C. Matasane, C. Dwarika, R. Naidoo

Abstract:

The mathematical analysis on radiation obtained and the development of the solar photovoltaic (PV) array groundwater pumping is needed in the rural areas of Thohoyandou, Limpopo Province for sizing and power performance subject to the climate conditions within the area. A simple methodology approach is developed for the directed coupled solar, controller and submersible ground water pump system. The system consists of a PV array, pump controller and submerged pump, battery backup and charger controller. For this reason, the theoretical solar radiation obtained for optimal predictions and system performance in order to achieve different design and operating parameters. Here the examination of the PV schematic module in a Direct Current (DC) application is used for obtainable maximum solar power energy for water pumping. In this paper, a simple efficient photovoltaic water pumping system is presented with its theoretical studies and mathematical modeling of photovoltaics (PV) system.

Keywords: renewable energy sources, solar groundwater pumping, theoretical and mathematical analysis of photovoltaic (PV) system, theoretical solar radiation

Procedia PDF Downloads 376
4865 Where Is the Sultan of Aceh? Reconsidering the Return of the Aceh Sultanate

Authors: Muhammad Harya Ramdhoni, Nidzam Sulaiman, Muhammad Ridwan

Abstract:

The Helsinki Agreement between the Indonesian Government (RI) and the Aceh Liberation Movement (GAM) on 15th Aug. 2005 fails to reconcile social and political turmoil in Aceh Darussalam (NAD). The political powers that were once unified in their struggle against Indonesian Government prior to this agreement have now become divided due to differences in political and economic interests. Using descriptive analysis and intellectual discourse, this paper proposes that the Aceh Sultanate be revived as an attempt to unite these divided political powers and to curtail potential conflicts in the area. This proposal is based on three assumptions. First, the Aceh Sultanate is the only Sultanate in Sumatera that did not fall victim to the social revolution post 1945 proclamation of independence. Second, the Acehnese still acknowledge the Sultanate as a sovereign political power even though it was defeated by the Dutch in 1904. Third, there are emotional, historical and cultural ties between the Acehnese and the Sultanate as they still perceived them to be their patron. Consequently, the Sultanate is the unifying element of all political powers in the area. This, however, is not an attempt to reinstate feudalism in Aceh. It only seeks to facilitate the political reconciliation process in Aceh Darussalam founded on sociological and historical background of locals.

Keywords: Sultanate Aceh, political reconciliation, political power, patron-client

Procedia PDF Downloads 265
4864 Experimental Analyses of Thermoelectric Generator Behavior Using Two Types of Thermoelectric Modules for Marine Application

Authors: A. Nour Eddine, D. Chalet, L. Aixala, P. Chessé, X. Faure, N. Hatat

Abstract:

Thermal power technology such as the TEG (Thermo-Electric Generator) arouses significant attention worldwide for waste heat recovery. Despite the potential benefits of marine application due to the permanent heat sink from sea water, no significant studies on this application were to be found. In this study, a test rig has been designed and built to test the performance of the TEG on engine operating points. The TEG device is built from commercially available materials for the sake of possible economical application. Two types of commercial TEM (thermo electric module) have been studied separately on the test rig. The engine data were extracted from a commercial Diesel engine since it shares the same principle in terms of engine efficiency and exhaust with the marine Diesel engine. An open circuit water cooling system is used to replicate the sea water cold source. The characterization tests showed that the silicium-germanium alloys TEM proved a remarkable reliability on all engine operating points, with no significant deterioration of performance even under sever variation in the hot source conditions. The performance of the bismuth-telluride alloys was 100% better than the first type of TEM but it showed a deterioration in power generation when the air temperature exceeds 300 °C. The temperature distribution on the heat exchange surfaces revealed no useful combination of these two types of TEM with this tube length, since the surface temperature difference between both ends is no more than 10 °C. This study exposed the perspective of use of TEG technology for marine engine exhaust heat recovery. Although the results suggested non-sufficient power generation from the low cost commercial TEM used, it provides valuable information about TEG device optimization, including the design of heat exchanger and the types of thermo-electric materials.

Keywords: internal combustion engine application, Seebeck, thermo-electricity, waste heat recovery

Procedia PDF Downloads 244
4863 Adaptive Discharge Time Control for Battery Operation Time Enhancement

Authors: Jong-Bae Lee, Seongsoo Lee

Abstract:

This paper proposes an adaptive discharge time control method to balance cell voltages in alternating battery cell discharging method. In the alternating battery cell discharging method, battery cells are periodically discharged in turn. Recovery effect increases battery output voltage while the given battery cell rests without discharging, thus battery operation time of target system increases. However, voltage mismatch between cells leads two problems. First, voltage difference between cells induces inter-cell current with wasted power. Second, it degrades battery operation time, since system stops when any cell reaches to the minimum system operation voltage. To solve this problem, the proposed method adaptively controls cell discharge time to equalize both cell voltages. In the proposed method, battery operation time increases about 19%, while alternating battery cell discharging method shows about 7% improvement.

Keywords: battery, recovery effect, low-power, alternating battery cell discharging, adaptive discharge time control

Procedia PDF Downloads 352