Search results for: voltage rise

Authors: Clémence Royer, Stéphane Mazouffre

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Nowadays, electric propulsion systems play a crucial role in space exploration missions due to their high specific impulse and long operational life. The Hall thrusters are one of the most mature EP technologies. It is a gridless ion thruster that has proved reliable and high-performance for decades in various space missions. Operation of HT relies on electron emissions through a cathode placed outside a hollow dielectric channel that includes an anode at the back. Negatively charged particles are trapped in a magnetic field and efficiently slow down. By collisions, the electron cloud ionizes xenon atoms. A large electric field is generated in the axial direction due to the low electron transverse mobility in the region of a strong magnetic field. Positive particles are pulled out of the chamber at high velocity and are neutralized directly at the exhaust area. This phenomenon leads to the acceleration of the spacecraft system at a high specific impulse. While HT’s architecture and operating principle are relatively simple, the physics behind thrust is complex and still partly unknown. Current and voltage oscillations, as well as electron properties, have been captured over a 30 mn time period after ignition. The observed low-frequency oscillations exhibited specific frequency ranges, amplitudes, and stability patterns. Correlations between the oscillations and plasma characteristics we analyzed. The impact of these instabilities on thruster performance, including thrust efficiency, has been evaluated as well. Moreover, strategies for mitigating and controlling these instabilities have been developed, such as filtering. In this contribution, in addition to presenting a summary of the results obtained in the transient regime, we will present and discuss recent advances in Hall thruster plasma discharge filtering and control.

Keywords: electric propulsion, Hall Thruster, plasma diagnostics, low-frequency oscillations

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Authors: Rakibul Islam Sagor, Sadia Ibnat Raisa

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Many nations across the globe, including Dhaka, are facing challenges in meeting the needs for a satisfactory quality of life due to the combination of a growing population and limited land resources. As a result, maximum spaces in modern cities are engulfed by concrete infrastructure, and there are hardly any open spaces in the urban neighborhoods. Although vertical movement has predominantly been employed for residential and commercial applications, the notion of vertical recreational and sports facilities remains unsettled. The primary objective of this study is to explore the feasibility of implementing vertical adaptations in urban recreational spaces, drawing upon the principles of high-rise theory. This article presents an analysis of the open spaces in Gulshan, Dhaka, focusing on the evaluation of the demand for open recreational and sports facilities that adequately cater to the existing population of the region. Initially, the study tried to identify and examine all potential open spaces within the designated area. Following that, an acceptable place is selected utilizing space syntax analysis, which takes into account the most conveniently accessible space for social interactions in the neighborhood. In addition, socioeconomic conditions of the area have been studied in order to determine the feasibility of the area. Finally, the study presented viable options for vertical urban sports facilities in the context of Dhaka, Bangladesh. Additionally, it seeks to develop strategies for maximizing the use of vertical expansions, thereby promoting a healthier and more active lifestyle among the city's residents. This approach aims to effectively handle the issue of limited land availability and enhance the efficiency of recreational areas around the globe.

Keywords: vertical sports, urban open spaces, social interaction, recreational activities

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Authors: Eki Farlen, Akas

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Condition assessment of oil-paper-insulated power transformers, particularly of water content, is becoming increasingly important for aged transformers. As insulation ages, it can produce water, which reduces its dielectric strength, accelerates the cellulose ageing process, and causes gas bubbles to form at high temperatures. This paper mainly assesses the life condition of oil-paper insulation system of Inter Bus Transformer (IBT) 30 MVA, 150/30 kV in PT PLN-Substation Jelok that has been operating for 41 years, since 1974. Valuable information about the condition of high voltage insulation may be obtained by measuring its dielectric response. This paper describes in detail the interpretation of Dielectric Response Analysis (DIRANA) measurements and the test result compared to other insulation tests to get deep information for diagnostic, such as Tan delta test, oil characteristic test and Dissolve Gas Analysis (DGA) test. This paper mainly discusses the parameter relationship between moisture content, water content, acidity, oil conductivity and dissipation factor. The result and analysis show that IBT 30 MVA Jelok phase U and W had just been ageing due to high acidity level (>0.2 mgKOH/g) which cause high moisture in cellulose/paper (%) are in wet category about 4.7% and 5% and water content in oil (ppm) about 3.13 ppm and 3.33 ppm at temperature 20°C. High acidity level can make oxidation process and produce water in paper and particle which can decrease the value of Interfacial Tension (IFT) below 22 mN/m (poor category) for both phase U and W. Even if paper insulation of transformer are in wet condition, dissipation factor and capacitance at the same frequency (50 Hz) from both measurement DIRANA test and Tangent delta test give the same result (almost), the results are 0.69% and 0.71% (<1%), it may be acceptable and should not be investigated. The DGA results show that TDCG are in level one (1) condition and there are no found a Key Gases, it means that transformers had no failure during operation like arching, partial discharge and thermal in oil or cellulose.

Keywords: diagnostic, inter-bus transformer, oil-paper insulation, moisture, dissipation factor

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Authors: Mohammed Alruwaili‬

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Nowadays, renewable energy resources are playing an important role in replacing traditional energy resources such as fossil fuels by integrating solar energy with conventional energy. Concerns about the environment led to an intensive search for a renewable energy source. The Rapid growth of distributed energy resources will have prompted increasing interest in the integrated distributing network in the Kingdom of Saudi Arabia next few years, especially after the adoption of new laws and regulations in this regard. Photovoltaic energy is one of the promising renewable energy sources that has grown rapidly worldwide in the past few years and can be used to produce electrical energy through the photovoltaic process. The main objective of the research is to study the impact of PV in distribution networks based on real data and details. In this research, site survey and computer simulation will be dealt with using the well-known computer program software ETAB to simulate the input of electrical distribution lines with other variable inputs such as the levels of solar radiation and the field study that represent the prevailing conditions and conditions in Diriah, Riyadh region, Saudi Arabia. In addition, the impact of adding distributed generation units (DGs) to the distribution network, including solar photovoltaic (PV), will be studied and assessed for the impact of adding different power capacities. The result has been achieved with less power loss in the loop distribution network from the current condition by more than 69% increase in network power loss. However, the studied network contains 78 buses. It is hoped from this research that the efficiency, performance, quality and reliability by having an enhancement in power loss and voltage profile of the distribution networks in Riyadh City. Simulation results prove that the applied method can illustrate the positive impact of PV in loop distribution generation.

Keywords: renewable energy, smart grid, efficiency, distribution network

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Authors: Shamim Ahsan

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Abstract Global digital advances associated with consumer’s strong inclination for the state of art digital technologies is causing overwhelming social and environmental challenges for global community. During recent years not only economic advances of electronic industries has taken place at steadfast rate, also the generation of e-waste outshined the growth of any other types of wastes. The estimated global e-waste volume is expected to reach 65.4 million tons annually by 2017. Formal recycling practices in developed countries are stemming economic liability, opening paths for illegal trafficking to developing countries. Informal crude management of large volume of e-waste is transforming into an emergent environmental and health challenge in. Contrariwise, in several studies formal and informal recycling of e-waste has also exhibited potentials for economic returns both in developed and developing countries. Some research on China illustrated that from large volume of e-wastes generation there are recycling potential in evolving from ∼16 (10−22) billion US$ in 2010, to an anticipated ∼73.4 (44.5−103.4) billion US$ by 2030. While in another study, researcher found from an economic analysis of 14 common categories of waste electric and electronic equipment (WEEE) the overall worth is calculated as €2.15 billion to European markets, with a potential rise to €3.67 billion as volumes increase. These economic returns and environmental protection approaches are feasible only when sustainable policy options are embraced with stricter regulatory mechanism. This study will critically review current researches to stipulate how global e-waste generation and sustainable e-waste recycling practices demonstrate future economic development potential in terms of both quantity and processing capacity, also triggering complex some environmental challenges.

Keywords: E-Waste, , Generation, , Economic Potential, Recycling

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Authors: Arpita Mondal, Aurobinda Routray, Sreeraj Puravankara, Rajashree Biswas

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The most difficult part of designing a battery management system (BMS) is battery modeling. A good battery model can capture the dynamics which helps in energy management, by accurate model-based state estimation algorithms. So far the most suitable and fruitful model is the equivalent circuit model (ECM). However, in real-time applications, the model parameters are time-varying, changes with current, temperature, state of charge (SOC), and aging of the battery and this make a great impact on the performance of the model. Therefore, to increase the equivalent circuit model performance, the parameter estimation has been carried out in the frequency domain. The battery is a very complex system, which is associated with various chemical reactions and heat generation. Therefore, it’s very difficult to select the optimal model structure. As we know, if the model order is increased, the model accuracy will be improved automatically. However, the higher order model will face the tendency of over-parameterization and unfavorable prediction capability, while the model complexity will increase enormously. In the time domain, it becomes difficult to solve higher order differential equations as the model order increases. This problem can be resolved by frequency domain analysis, where the overall computational problems due to ill-conditioning reduce. In the frequency domain, several dominating frequencies can be found in the input as well as output data. The selective frequency domain estimation has been carried out, first by estimating the frequencies of the input and output by subspace decomposition, then by choosing the specific bands from the most dominating to the least, while carrying out the least-square, recursive least square and Kalman Filter based parameter estimation. In this paper, a second order battery model consisting of three resistors, two capacitors, and one SOC controlled voltage source has been chosen. For model identification and validation hybrid pulse power characterization (HPPC) tests have been carried out on a 2.6 Ah LiFePO₄ battery.

Keywords: equivalent circuit model, frequency estimation, parameter estimation, subspace decomposition

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Authors: Olusola Joseph Adesina, Sunmaila Oyetunji Raimi, Olufemi Akinloye Bolaji, Abiodun Ezekiel Adesina

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The quality of education and the standard of a nation cannot rise above the quality of the teacher (NPE, 2004). Efforts at improving the falling standard of education in the country call for the need-based assessment of the primary tier of education in Nigeria. It was revealed that the teachers’ standard of performance and pupils’ achievement was below average. Teachers’ cluster meeting intervention was therefore recommended as a step towards enhancing the teachers’ professional competency, efficient and effective proactive and interactive lesson presentation. The study thus determined the impact of the intervention on teachers’ professional performance (lesson note preparation and teaching performance) in Oyo State, Nigeria. The main and interaction effects of the gender of the teachers as moderator variable were also determined. Three null hypotheses guided the study. Pre-test, posttest control group quazi experimental design was adopted for the study. Three hundred intact classes from three hundred different schools were randomly selected into treatment and control groups. Two response instruments-Classroom Lesson Note Preparation Checklist (CLNPC; r = 0.89) Cluster Lesson Observation Checklist (CLOC; r = 0.86) were used for data collection. Mean, Standard deviation and Analysis of Covariance (ANCOVA) were used to analyse the collected data. The results showed that the teachers’ cluster meeting have significant impact on teachers’ lesson note preparation (F(1,295) = 31.607; p < 0.05; η2 = .097) and teaching performance (F(1,295) = 20.849; p < 0.05; η2 = .066) in the core subjects of primary schools in Oyo State, Nigeria. The study therefore recommended among others that teachers’ cluster meeting should be sustained for teachers’ professional development in the State.

Keywords: teachers’ cluster meeting, teacher lesson note preparation, teaching performance, teachers’ gender, primary schools in Oyo state

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Authors: Deniz Erten

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This paper delves into the multifaceted nature of human consciousness, examining its structure through the lens of three distinct selves. These selves represent varying thresholds of consciousness, characterized by seven soul levels and seven nafs levels. The attainment of gamma brain wave states signifies the emergence of the Perfect Human Being, whose consciousness transcends the boundaries of individuality to encompass the entirety of existence. Central to this exploration is the notion that consciousness pervades all aspects of reality, underscoring the significance of a comprehensive understanding of the concept of God. Contrary to conventional beliefs, God is not to be construed as a person but rather as an all-encompassing consciousness that manifests within every sentient being. The post-mortem journey through black holes and wormholes, culminating in an encounter with one's creations in the quantum field, provides compelling evidence for the mental nature of the universe. Drawing distinctions between mind and consciousness, as well as self and spirit, elucidates the intricate dynamics underlying human existence. The fusion of body and spirit gives rise to the self, or avatar, which undergoes trials to ascend towards divine consciousness within the Creator's simulated reality. The concept of observation, rooted in the Arabic term "Shahada," underscores the importance of introspection in the quest for enlightenment. The convergence of disciplines such as quantum physics, neuroscience, and religious scriptures like the Quran highlights humanity's collective state of unawareness, with dreams serving as windows into different levels of consciousness. This study further explores the nuanced relationship between consciousness and self, examining the hierarchical progression of the avatar's journey towards spiritual realization.

Keywords: avatar, black holes, cosmic interconnectedness, consciousness, divine matrix, divine simulation, existential exploration, God consciousness, interdisciplinary perspective, levels of consciousness, quantum field, Quran, spiritual realization, Sufism, universal consciousness

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Authors: Vladimir Sharapaev

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This paper seeks to address the question of the authorship of copyrighted works created solely by the artificial intelligence or with the use thereof, and proposes possible interpretational or legislative solutions to the problems arising from the plurality of the persons potentially involved in the ultimate creation of the work and division of tasks among such persons. Being based on the commonly accepted assumption that a copyrighted work can only be created by a natural person, the paper does not deal with the issues regarding the creativity of the artificial intelligence per se (or the lack thereof), and instead focuses on the distribution of the intellectual property rights potentially belonging to the creators of the artificial intelligence and/or the creators of the content used for the formation of the copyrighted work. Moreover, the technical development and rapid improvement of the AI-based programmes, which tend to be reaching even greater independence on a human being, give rise to the question whether the initial creators of the artificial intelligence can be entitled to the intellectual property rights to the works created by such AI at all. As the juridical practice of some European courts and legal doctrine tends to incline to the latter opinion, indicating that the works created by the AI may not at all enjoy copyright protection, the questions of authorships appear to be causing great concerns among the investors in the development of the relevant technology. Although the technology companies dispose with further instruments of protection of their investments, the risk of the works in question not being copyrighted caused by the inconsistency of the case law and a certain research gap constitutes a highly important issue. In order to assess the possible interpretations, the author adopted a doctrinal and analytical approach to the research, systematically analysing the European and Czech copyright laws and case law in some EU jurisdictions. This study aims to contribute to greater legal certainty regarding the issues of the authorship of the AI-created works and define possible clues for further research.

Keywords: artificial intelligence, copyright, authorship, copyrighted work, intellectual property

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Authors: Karl Gerrard Tiu See

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Military bases are an indelible mark of prolonged US defense relationships in the Pacific. Bases like the Subic Naval Base in Olongapo City have irreversible consequences for their host communities, not all of which are positive. One consequence the Subic Naval Base had for Olongapo City was the rise of vibrant sex industry. While the Philippine Senate voted to remove US bases like Subic in 1991, the question remains as to why did prostitution not end after the bases pull-out? To answer this question, the study used an institutionalist lens coupled with focus group discussions from the sex industry. It found that prostitution persisted due to two main reasons. The first was that like Olongapo City; the sex industry successfully shifted its reliance from the military to foreign tourism. The second was that agreements such as the 1996 Visiting Forces Agreement (VFA) ensured that the sex industry continued to receive US military clientele. With the contextual factors as the backdrop, this study used the Theory of Institutional Change to study institutions pivotal in altering Olongapo City and its sex industry after Subic Naval Base. These include local government, civil society actors such as NGOs, and the city’s economic base. The study found that policy such as the VFA allowed the bases period status quo to revive (Symbionts). This led to renewed exploitation from the military presence coupled with foreign tourism (Opportunists). The local government, however, shifted focus away from base reliance which allowed a reinvigorated civil society to effect a gradual change (Subversives). Furthermore, uncertainties like rising HIV incidence, abandoned children born from US soldiers, and the Enhanced Defence Cooperation Agreement (EDCA) remain to change the sex industry’s future, for better or worse.

Keywords: Philippine-USA defence relations, overseas USA basing, 1991 Philippine-USA bases pull-out, Olongapo city, Subic naval base, institutional change

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Authors: Golam Saklayen, Sheikh Rashel al Ahmed, Ferdous Rahman, Ismail Abu Bakar

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Investigation on Lanthanum Fluoride LaF3 layer embedding Silicon Nanocrystals (Si-NCs) fabricated using a novel one-step chemical method has been reported in this presentation. Application of this material has been tested for low-voltage operating non-volatile memory and Schottkey-junction solar cell. Colloidal solution of Si-NCs in hydrofluoric acid (HF) was prepared from meso-porous silicon by ultrasonic vibration (sonication). This solution prevents the Si-NCs to be oxidized. On a silicon (Si) substrate, LaCl3 solution in HCl is allowed to react with the colloidal solution of prepared Si-NCs. Since this solution contains HF, LaCl3 reacts with HF and produces LaF3 crystals that deposits on the silicon substrate as a layer embedding Si-NCs. This a novel single step chemical way of depositing LaF3 insulating layer embedding Si-NCs. The X-Ray diffraction of the deposited layer shows a polycrystalline LaF3 deposition on silicon. A non-stoichiometric LaF3 layer embedding Si-NCs was found by EDX analysis. The presence of Si-NCs was confirmed by SEM. FTIR spectroscopy of the deposited LaF3 powder also confirmed the presence of Si-NCs. The size of Si-NCs was found to be inversely proportional to the ultrasonic power. After depositing proper contacts on the back of Si and LaF3, the devices have been tested as a non-volatile memory and solar cell. A memory window of 525 mV was obtained at a programming and erasing bias of 2V. The LaF3 films with Si NCs showed strong absorption and was also found to decrease optical transmittance than pure LaF3 film of same thickness. The I-V characteristics of the films showed a dependency on the incident light intensity where current changed under various light illumination. Experimental results show a lot of promise for Si-NCs-embedded LaF3 layer to be used as an insulating layer in MIS devices as well as an photoactive material in Schottkey junction solar cells.

Keywords: silicon nanocrystals (Si NCs), LaF3, colloidal solution, Schottky junction solar cell

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Authors: Sohni Siddiqui, Anja Schultze-Krumbholz

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Our lives now revolve more around online-related tasks, as the internet has become a necessity. One of the disturbance concerns with high internet usage is the multiplication of cyber-associated risky behaviors such as cyber aggression and/or cyberbullying. Cyber Bullying is an emerging issue that needs immediate attention from many stakeholders such as parents, doctors, school administrators, policymakers, researchers, and others, especially in the COVID-19 pandemic when online learning has been adopted as an instructional strategy, and there is a continuous rise in cyberbullying cases. The aim of the article is to review existing successful and emerging interventions designed to control bullying and cyberbullying by engaging individuals through teachers’ professional development and adopting a whole-school approach. The study identified the strengths and limitations of the programs and suggested improvements to existing interventions. Preparing interventions with a strong theoretical framework, integrating applications of emerging theories in interventions, promoting proactive and reactive strategies in combination, beginning with the baseline needs assessment surveys, reducing digital time and digital divide among parents and children, promoting the concept of lead trainer, peer trainer, and hot spots, focusing on physical activities, use of landmarks are some of the recommendations proposed by authors. In addition to face-to-face intervention, the researchers recommend updating and improving previous intervention programs with games and apps. Especially in the time of pandemic crises, when face-to-face interactions are limited and cyberbullying is triggered, the use of apps, web-based interventions, and games can be an effective way to control electronic perpetration and victimization.

Keywords: anti bullying programs, cyber bullying, individualized trainings, teachers’ professional development, whole school interventions

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Authors: Tamale Vincent

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Groundwater investigation is the investigation of underground formations to understand the hydrologic cycle, known groundwater occurrences, and identify the nature and types of aquifers. There are different groundwater investigation methods and surface geophysical method is one of the groundwater investigation more especially the Geoelectrical resistivity Schlumberger configuration method which provides valuable information regarding the lateral and vertical successions of subsurface geomaterials in terms of their individual thickness and corresponding resistivity values besides using surface geophysical method, hydrogeological and geological investigation methods are also incorporated to aid in preliminary groundwater investigation. Investigation for groundwater in lwantonde district has been implemented. The area project is located cattle corridor and the dry seasonal troubles the communities in lwantonde district of which 99% of people living there are farmers, thus making agriculture difficult and local government to provide social services to its people. The investigation was done using the Geoelectrical resistivity Schlumberger configuration method. The measurement point is located in the three sub-counties, with a total of 17 measurement points. The study location is at 0025S, 3110E, and covers an area of 160 square kilometers. Based on the results of the Geoelectrical information data, it was found two types of aquifers, which are open aquifers in depth ranging from six meters to twenty-two meters and a confined aquifer in depth ranging from forty-five meters to eighty meters. In addition to the Geoelectrical information data, drilling was done at an accessible point by heavy equipment in the Lwakagura village, Kabura sub-county. At the drilling point, artesian wells were obtained at a depth of eighty meters and can rise to two meters above the soil surface. The discovery of artesian well is then used by residents to meet the needs of clean water and for irrigation considering that in this area most wells contain iron content.

Keywords: artesian well, geoelectrical, lwantonde, Schlumberger

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Authors: A. Rostampouryasouri, A. Maghoul, S. Tahersima

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The rapid growth of urbanization and the subsequent increase in population in cities have resulted in the destruction of the environment to cater to the needs of citizens. The industrialization of urban life has led to the production of pollutants, which has significantly contributed to the rise of air pollution. Infrastructure can have both positive and negative effects on air pollution. The effects of infrastructure on air pollution are complex and depend on various factors such as the type of infrastructure, location, and context. This study examines the effects of infrastructure on air pollution, drawing on a range of empirical evidence from Iran and China. Our paper focus for analyzing the data is on the following concepts: 1. Urban design and planning principles and practices 2. Infrastructure efficiency and optimization strategies 3. Public transportation systems and their environmental impact 4. GHG emissions reduction strategies in urban areas 5. Case studies and best practices in sustainable urban development This paper employs a mixed methodology approach with a focus on developmental and applicative purposes. The mixed methods approach combines both quantitative and qualitative research methods to provide a more comprehensive understanding of the research topic. A group of 20 architectural specialists and experts who are proficient in the field of research, design, and implementation of green architecture projects were interviewed in a systematic and purposeful manner. The research method was based on content analysis using MAXQDA2020 software. The findings suggest that policymakers and urban planners should consider the potential impacts of infrastructure on air pollution and take measures to mitigate negative effects while maximizing positive ones. This includes adopting a nature-based approach to urban planning and infrastructure development, investing in information infrastructure, and promoting modern logistic transport infrastructure.

Keywords: GHG emissions, infrastructure efficiency, urban development, urban design

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Authors: Quin Emparan, Razif Harun, Dayang R. A. Biak, Rozita Omar, Michael K. Danquah

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Cultivation of immobilized microalgae cells is on the rise for biotechnological applications. In this study, cultivation of Chlorella vulgaris was carried out in the form of suspended free-cell and immobilized cells system. NaCS-PDMDAAC capsules were used to immobilize C. vulgaris. Initially, the synthesized NaCS with C. vulgaris culture were prepared at various concentration of 5- 20% (w/v) using a 6% hardening solution (PDMDAAC) to investigate the capsules' gel stability and suitability for microalgae cells growth. Then, the capsules produced from 15% NaCS with C. vulgaris culture were furthered investigated using 5%, 10%, and 15% (w/v) of PDMDAAC solution. The capsules' gel stability was evaluated through dissolution time and loss of uniform spherical shape of capsules, while suitability for microalgae cells growth was evaluated through the optical density of microalgae. In this study, the 15% NaCS-10% PDMDAAC capsules were found to be the most suitable to sustain the capsules' gel stability and microalgae cells growth in MLA. For that reason, the C. vulgaris immobilized in the 15% NaCS-10% PDMDAAC capsules were further characterized using physicochemical analysis in terms of morphological, carbon (C), hydrogen (H) and nitrogen (N), Fourier transform-infrared (FT-IR), scanning electron microscopy-energy dispersive X-ray (SEM-EDX), zeta potential and Brunauer-Emmet-Teller (BET) analyses. The results revealed that the presence of sulfonates in the synthesized NaCS and NaCS-PDMDAAC capsules without and with C. vulgaris proves that cellulose alcohol group was successfully bonded by sulfo group. Besides that, immobilized microalgae cells have a smaller cell size of 6.29 ± 1.09 µm and zeta potential of -11.93 ± 0.91 mV than suspended free-cells microalgae culture. It can be summarized that immobilization of C. vulgaris in the 15% NaCS-10% PDMDAAC capsules are relevant as a bioremediator for wastewater treatment purposes due to its suitable size of pore and capsules as well as structural and compositional properties.

Keywords: biological capsules, immobilized cultivation, microalgae, physico-chemical analysis

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Authors: Mehak Masood

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This paper aims to design an integrated solid waste management plan for industrial estates taking Sundar Industrial Estate as case model. The issue of solid waste management is on the rise in Pakistan especially in the industrial sector. In this regard, the concept of development and establishment of industrial estates is gaining popularity nowadays. Without proper solid waste management plan it is very difficult to manage day to day affairs of industrial estates. An industrial estate contains clusters of different types of industrial units. It is necessary to identify different types of solid waste streams from each industrial cluster within the estate. In this study, Sundar Industrial Estate was taken as a case model. Primary and secondary data collection, waste assessment, waste segregation and weighing and field surveys were essential elements of the study. Wastes from each industrial process were identified and quantified. Currently 130 industries are in production but after full colonization of industries this number would reach 385. Elaborated process flow diagrams were made to characterize the recyclable and non-recyclables waste. From the study it was calculated that about 12354.1 kg/captia/day of solid waste is being generated in Sundar Industrial Estate. After the full colonization of the industrial estate, the estimated quantity will be 4756328.5 kg/captia/day. Furthermore, solid waste generated from each industrial sector was estimated. Suggestions for collection and transportation are given. Environment friendly solid waste management practices are suggested. If an effective integrated waste management system is developed and implemented it will conserve resources, create jobs, reduce poverty, conserve natural resources, protect the environment, save collection, transportation and disposal costs and extend the life of disposal sites. A major outcome of this study is an integrated solid waste management plan for the Sundar Industrial Estate which requires immediate implementation.

Keywords: integrated solid waste management plan, industrial estates, Sundar Industrial Estate, Pakistan

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Authors: Aimite Jorge, Leenekela Usebiu

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In recent years the International Community has seen a rise of what can be termed as ‘actio popularis”;that is to say lawsuits brought by third parties in the interest of the public or the world community as a whole, such as in cases of genocide and terrorism prosecutions under international law. It is equally clear that under current globalized world the effect of multinational activities on the environment is often felt beyond the borders of the territories where they operate. Equally true is the fact that the correspondence of citizens self-determination with national government is increasingly upset by the increasing willingness of states to share some ‘sovereign powers’ in order to address new economic, environmental and security interdependencies. The ‘unbundling’ of functional governance from fixed territories sees continuously citizens give up their formal approval of key decisions in exchange for a more remote, indirect say in supra-national or international decision-making bodies. The efforts to address a growing transnational flow of ecological harm are at the forefront of such indirect transformations, as evidenced by a proliferation of multilateral environmental agreements (MEAs) over the past three decades. However, unlike the defence of the global commons in cases of terrorism and genocide, there is still to be a clear application of action popularis in the case of environment, despite acknowledgement that the effect of the activities of several multinationals on the environment is as destructive to the global commons as genocide or terrorism are. Thus, this paper looking at specific cases of harmful degradation of the environment by certain multinationals transcending national boundaries, argues that it is high-time for a serious consideration of the application of the actio-popularis to environmental concerns. Although it is acknowledged that in international environmental law the challenge to reach a “critical mass” of recognition and support for an ‘actio-popularis’ for environment damage is particularly demanding, it is worth the try.

Keywords: actio popularis in environment law, global commons, transnational environmental damage, law and environment

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Authors: Michal Biały, Krzysztof Skiba, Zdzislaw Kaminski

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The research results of the influence of the adjustable mutual position of the propellers for getting optimal lift force on a specially designed bench. The bench consists of frame with electric motors and with attached propellers. Engines were arranged in a matrix of two columns and three rows. The distance between the columns averages from 0 to 20”, while the engine was placed at a height of 8”, 15.5” and 23.6”. By adjusting the tilt of an electric motor, an angle of the propeller in the range of 0° to 60°, by 15° was controlled. Propellers with a diameter of 8" and pitch of 4.5” were driven by brushless model engines Roxxy BL-Outrunner 2827/26 with a power of 110W (each). Rotational speed control of electric motors were realized parallel for all propellers. The speed adjustment was realized using an aggregate of radio-controlled regulators. Electric power supplied to the engines from zero to maximum power, by the setting for every 14W, was controlled by radio system. Measurement system was placed on a laboratory scale. The lift was measured and recorded by an electronic scale. The lift force for different configurations of propellers arrangement was recorded during the test. All propellers were driven in one rotational direction and in different directions when they were in the same pairs. Propellers were driven concurrently and contra-concurrently along one of the columns and along the selected rows. During the tests, except the lift, parameters such as: rotational speed of propellers, voltage and current to the electric engines were recorded. The main aim of the research was to show the influence of aerodynamic interference between the propellers to receive lift force depending on the drive configuration of individual propellers. The research has shown that, this interference exists. The increase of the lift force for a distance between columns above 26.6” was noticed during the driving propellers in different directions. The optimum tilt angle of the propeller was 45°. Furthermore there has been also approx. 12% increase of the lift for propellers driven alternately in column and contra-concurrently in relation to the contra-rotating drive in the row.

Keywords: aerodynamic, interference, lift force, propeller, propulsion system

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Authors: Daniel Barkley, Jianyi Zhu

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This study investigates base salary differentials and gender equity among university presidents across 427 U.S. colleges and universities. While endowments typically do not directly determine university presidents' base salaries, our analysis reveals a noteworthy pattern: endowments explain more than half of the variance in female university presidents' base salaries, compared to a mere 0.69 percent for males. Moreover, female presidents' base salaries tend to rise much faster than male base salaries with increasing university endowments. This disparate impact of endowments on base salaries implies an endowment threshold for achieving gender pay equity. We develop an analytical model predicting an endowment threshold for achieving gender equality and empirically estimate this equity threshold using data from over 427 institutions. Surprisingly, the fields of science and athletics have emerged as sources of gender-neutral base pay. Both male and female university presidents with STEM backgrounds command higher base salaries than those without such qualifications. Additionally, presidents of universities affiliated with Power 5 conferences consistently receive higher base salaries regardless of gender. Consistent with the theory of human capital accumulation, the duration of the university presidency incrementally raises base salaries for both genders but at a diminishing rate. Curiously, prior administrative leadership experience as a vice president, provost, dean, or department chair does not significantly influence base salaries for either gender. By providing empirical evidence and analytical models predicting an endowment threshold for achieving gender equality in base salaries, the study offers valuable insights for policymakers, university administrators, and other stakeholders. These findings hold crucial policy implications, informing strategies to promote gender equality in executive compensation within higher education institutions.

Keywords: higher education, endowments, base salaries, university presidents

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Authors: Jiahui Song

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The use of electric fields with high intensity (~ 100kV/cm or higher) and ultra short pulse durations (nanosecond range) has been a recent development. Most of the studies of electroporation have ignored possible thermal effects because of the small duration of the applied voltage pulses. However, it has been predicted membrane temperature gradients ranging from 0.2×109 to 109 K/m. This research focuses on thermal effects that drive for electroporative enhancements, even though the actual temperature values might not have changed appreciably from their equilibrium levels. The dynamics of pore formation with the application of an externally applied electric field is studied on the basis of molecular dynamics (MD) simulations using the GROMACS package. MD simulations of a lipid layer with constant electric field strength of 0.5 V/nm at 25 °C and 47 °C are implemented to simulate the appropriate thermal effects. The GROMACS provides the force fields for the lipid membranes, which is taken to comprise of dipalmitoyl-phosphatidyl-choline (DPPC) molecules. The water model mimicks the aqueous environment surrounding the membrane. Velocities of water and membrane molecules are generated randomly at each simulation run according to a Maxwellian distribution. The high background electric field is typically used in MD simulations to probe electroporation. It serves as an accelerated test of the pore formation process since low electric fields would take inordinately long simulation time. MD simulation shows no pore is formed in a 1-ns snapshot for a DPPC membrane set at a temperature of 25°C after a 0.5 V/nm electric field is applied. A nano-sized pore is clearly seen in a 0.75-ns snapshot on the same geometry, but with the membrane surfaces kept at temperatures of 47°C. And the pore increases at 1 ns. The MD simulation results suggest the possibility that the increase in temperature can result in different degrees of electrically stimulated bio-effects. The results points to the role of thermal effects in facilitating and accelerating the electroporation process.

Keywords: high-intensity, ultra-short, electroporation, thermal effects, molecular dynamics

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Authors: Svanik Garg

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Static Test Pads are stationary mechanisms that hold a solid rocket motor, measuring the different parameters of its operation including thrust and temperature to better calibrate it for launch. This paper outlines a specific STP designed to test high powered rocket motors with a thrust upwards of 4000N and limited to 6500N. The design includes a specific portable mechanism with cost an integral part of the design process to make it accessible to small scale rocket developers with limited resources. Using curved surfaces and an ergonomic design, the STP has a delicately engineered façade/case with a focus on stability and axial calibration of thrust. This paper describes the design, operation and working of the STP and its widescale uses given the growing market of aviation enthusiasts. Simulations on the CAD model in Fusion 360 provided promising results with a safety factor of 2 established and stress limited along with the load coefficient A PCB was also designed as part of the test pad design process to help obtain results, with visual output and various virtual terminals to collect data of different parameters. The circuitry was simulated using ‘proteus’ and a special virtual interface with auditory commands was also created for accessibility and wide-scale implementation. Along with this description of the design, the paper also emphasizes the design principle behind the STP including a description of its vertical orientation to maximize thrust accuracy along with a stable base to prevent micromovements. Given the rise of students and professionals alike building high powered rockets, the STP described in this paper is an appropriate option, with limited cost, portability, accuracy, and versatility. There are two types of STP’s vertical or horizontal, the one discussed in this paper is vertical to utilize the axial component of thrust.

Keywords: static test pad, rocket motor, thrust, load, circuit, avionics, drag

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Authors: Amir Mirzaei

Abstract:

The powertrain system is one of the most basic and essential components in a machine. The occurrence of motion is practically impossible without the presence of this system. When power is generated by the engine, it is transmitted by the powertrain system to the wheels, which are the last parts of the system. Powertrain system has different components according to the type of use and design. When the force generated by the engine reaches to the wheels, the amount of frictional force between the tire and the ground determines the amount of traction and non-slip or the amount of slip. At various levels, such as icy, muddy, and snow-covered ground, the amount of friction coefficient between the tire and the ground decreases dramatically and considerably, which in turn increases the amount of force loss and the vehicle traction decreases drastically. This condition is caused by the phenomenon of slipping, which, in addition to the waste of energy produced, causes the premature wear of driving tires. It also causes the temperature of the transmission oil to rise too much, as a result, causes a reduction in the quality and become dirty to oil and also reduces the useful life of the clutches disk and plates inside the transmission. this issue is much more important in road construction and mining machinery than passenger vehicles and is always one of the most important and significant issues in the design discussion, in order to overcome. One of these methods is the automatic spin regulator system which is abbreviated as ASR. The importance of this method and its structure and function have solved one of the biggest challenges of the powertrain system in the field of construction and mining machinery. That this research is examined.

Keywords: automatic spin regulator, ASR, methods of reducing slipping, methods of preventing the reduction of the useful life of clutches disk and plate, methods of preventing the premature dirtiness of transmission oil, method of preventing the reduction of the useful life of tires

Procedia PDF Downloads 56

Authors: Mohamed Montassar Ben Slama, Mohamed Fadel Ladeb, Mohamed Ghanmi, Mohamed Ben Youssef, Fouad Zargouni

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The salt province Basin in Northern Tunisia is a complex of late Triassic to Early Cretaceous rift and sag basins which was inverted during the Tertiary folding. The deposition of evaporitic sediments during the Late Triassic times played a major role in the subsequent tectonic evolution of the basin. Within southern tethyan passive marge, the ductile salt mass shown early mobilization, vertical transport and withdrawal of the evaporites. These movements influenced the sedimentation during the late Jurassic and Early Cretaceous. The evaporites also influenced deformation during the inversion of the basin and the development of the Tertiary and Quaternary folding. In the studied area, the biostratigraphic and tectonic map analysis of the region of Jebel el Asoued / Ragoubet el Mahjbia can resolve between the hypotheses of the diapiric intrusion of the Triassic salt and the lateral spreading of the Triassic salt as salt ‘glacier’. Also the variation in thickness and facies of the Aptian sediments demonstrates the existence of continental rise architecture at the Aptian time. The observation in a mappable outcrop of the extension segment of the graben fault of Bou Arada on the one hand confirms the existence of a Cretaceous extensive architecture and the tectonic inversion during the Tertiary time has not filled the main game distension. The extent of our observations of Triassic/Aptian and Triassic/Early Campanian contacts, we propose a composite salt ‘glacier’ model as the structures recorded in the Gulf of Mexico in the subsurface and in the Ouenza east Algeria and in Tunisia within Fedj el Adoum, Touiref-Nebeur and Jebel Ech Cheid in the outcrops.

Keywords: Cretaceous rift, salt ‘glassier’, tertiary folding, Tunisia

Procedia PDF Downloads 353

Authors: Auwal Garba, Rabiu Maijama’a, Abdullahi Muhammad Jalam

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Variability in climate has affected the agricultural production all over the globe. This concern has motivated important changes in the field of research during the last decade. Climate variability is believed to have declining effects towards rice production in Nigeria. This study examined climate variability and its impact on rice productivity in Dass Local Government Area, Bauchi State, by employing Linear Trend Model (LTM), analysis of variance (ANOVA) and regression analysis. Annual seasonal data of the climatic variables for temperature (min. and max), rainfall, and solar radiation from 1990 to 2015 were used. Results confirmed that 74.4% of the total variation in rice yield in the study area was explained by the changes in the independent variables. That is to say, temperature (minimum and maximum), rainfall, and solar radiation explained rice yield with 74.4% in the study area. Rising mean maximum temperature would lead to reduction in rice production while moderate increase in mean minimum temperature would be advantageous towards rice production, and the persistent rise in the mean maximum temperature, in the long run, will have more negatively affect rice production in the future. It is, therefore, important to promote agro-meteorological advisory services, which will be useful in farm planning and yield sustainability. Closer collaboration among the meteorologist and agricultural scientist is needed to increase the awareness about the existing database, crop weather models among others, with a view to reaping the full benefits of research on specific problems and sustainable yield management and also there should be a special initiative by the ADPs (State Agricultural Development Programme) towards promoting best agricultural practices that are resilient to climate variability in rice production and yield sustainability.

Keywords: climate variability, impact, productivity, rice

Procedia PDF Downloads 79

Authors: K. S. Sivakumaran, T. Thanga, B. Halabieh

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The end panels of a large rectangular industrial duct, which experience significant internal pressures, also experience considerable transverse shear due to transfer of gravity loads to the supports. The current design practice of such thin plate panels for shear load is based on methods used for the design of plate girder webs. The structural arrangements, the loadings and the resulting behavior associated with the industrial duct end panels are, however, significantly different than those of the web of a plate girder. The large aspect ratio of the end panels gives rise to multiple bands of tension fields, whereas the plate girder web design is based on one tension field. In addition to shear, the industrial end panels are subjected to internal pressure which in turn produces significant membrane action. This paper reports a study which was undertaken to review the current industrial analysis and design methods and to propose a comprehensive method of designing industrial duct end panels for shear resistance. In this investigation, a nonlinear finite element model was developed to simulate the behavior of industrial duct end panel subjected to transverse shear and internal pressures. The model considered the geometric imperfections and constitutive relations for steels. Six scale independent dimensionless parameters that govern the behavior of such end panel were identified and were then used in an extensive parametric study. It was concluded that the plate slenderness dominates the shear strength of stockier end panels, and whereas, the aspect ratio and plate slenderness influence the shear strength of slender end panels. Based on these studies, this paper proposes design aids for estimating the shear strength of rectangular duct end panels.

Keywords: thin plate, transverse shear, tension field, finite element analysis, parametric study, design

Procedia PDF Downloads 202

Authors: Koustav Pal, Indranil Das

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In recent times, perovskite and double perovskite (DP) systems attracts lot of interest as they provide a rich material platform for studying emergent functionalities like near-room-temperature ferromagnetic (FM) insulators, exchange bias (EB), magnetocaloric effects, colossal magnetoresistance, anisotropy, etc. These interesting phenomena emerge because of complex couplings between spin, charge, orbital, and lattice degrees of freedom in these systems. Various magnetic phenomena such as exchange bias, spin glass, memory effect, colossal magneto-resistance, etc. can be modified and controlled through antisite (B-site) disorder or controlling oxygen concentration of the material. By controlling oxygen concentration in SrFe0.5Co0.5O3 – δ (SFCO) (δ ∼ 0.3), we achieve intrinsic exchange bias effect with a large exchange bias field (∼1.482 Tesla) and giant coercive field (∼1.454 Tesla). Now we modified the B-site by introducing 10% iridium in the system. This modification give rise to the exchange bias field as high as 1.865 tesla and coercive field 1.863 tesla. Our work aims to investigate the effect of oxygen deficiency and B-site effect on exchange bias in oxide materials for potential technological applications. Structural characterization techniques including X-ray diffraction, scanning tunneling microscopy, and transmission electron microscopy were utilized to determine crystal structure and particle size. X-ray photoelectron spectroscopy was used to identify valence states of the ions. Magnetic analysis revealed that oxygen deficiency resulted in a large exchange bias due to a significant number of ionic mixtures. Iridium doping was found to break interaction paths, resulting in various antiferromagnetic and ferromagnetic surfaces that enhance exchange bias.

Keywords: coercive field, disorder, exchange bias, spin glass

Procedia PDF Downloads 51

Authors: Kimberly Tasha Jiayi Tang, Changqing Lin, Zhe Wang, Tze-Wai Wong, Md. Shakhaoat Hossain, Jian Yu, Alexis Lau

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Hong Kong has practiced a risk-based Air Quality Health Index (AQHI) system that sums hospitalization risks associated with short-term exposure to air pollu-tants. As an air pollution risk communication tool, it informs the public about the current air quality, anchoring around the World Health Organization's (WHO) 2005 Air Quality Guidelines (AQGs). Given the WHO's recent update in 2021, assessing how Hong Kong’s air quality risk communication can be en-hanced using these updated guidelines is essential. Hong Kong’s AQHI is lim-ited by solely focusing on short-term health risks, which could lead the public to underestimate cumulative health impacts. Therefore, we propose the intro-duction of a composite AQHI that reports both long-term and short-term health risks. Additionally, the WHO interim targets will be considered as anchor points for various health risk categories. Furthermore, with the increasing ozone levels in Hong Kong and Southern China due to improved NOx mitigation measures, it has been a challenging task in balancing health protection against climate mitigation. However, our findings present a promising outlook. Despite the rise in ozone levels, the combined health risks in Hong Kong and Guang-dong have seen a decline, largely due to reductions in NO2 and PM concentra-tions, both having significant health implications. By shifting from a concentra-tion-based approach to a health risk-based system like the AQHI, our study highlights the prospective of harmonizing health protection and climate mitiga-tion goals. This health-focused framework suggests that rigorous NOx controls can effective-ly serve both objectives in parallel.

Keywords: air quality management, air quality health index, health risk management, air pollution

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Authors: Umair Ahmed, Muhammad Bin Irfan

Abstract:

This study focuses on designing and optimization of an alkaline water electrolyser for the production of green hydrogen. The aim is to enhance the durability and efficiency of this technology while simultaneously reducing the cost associated with the production of green hydrogen. The experimental results obtained from the alkaline water electrolyser are compared with simulated results using Aspen Plus software, allowing a comprehensive analysis and evaluation. To achieve the aforementioned goals, several design and operational parameters are investigated. The electrode material, electrolyte concentration, and operating conditions are carefully selected to maximize the efficiency and durability of the electrolyser. Additionally, cost-effective materials and manufacturing techniques are explored to decrease the overall production cost of green hydrogen. The experimental setup includes a carefully designed alkaline water electrolyser, where various performance parameters (such as hydrogen production rate, current density, and voltage) are measured. These experimental results are then compared with simulated data obtained using Aspen Plus software. The simulation model is developed based on fundamental principles and validated against the experimental data. The comparison between experimental and simulated results provides valuable insight into the performance of an alkaline water electrolyser. It helps to identify the areas where improvements can be made, both in terms of design and operation, to enhance the durability and efficiency of the system. Furthermore, the simulation results allow cost analysis providing an estimate of the overall production cost of green hydrogen. This study aims to develop a comprehensive understanding of alkaline water electrolysis technology. The findings of this research can contribute to the development of more efficient and durable electrolyser technology while reducing the cost associated with this technology. Ultimately, these advancements can pave the way for a more sustainable and economically viable hydrogen economy.

Keywords: sustainable development, green energy, green hydrogen, electrolysis technology

Procedia PDF Downloads 54

Authors: Nithya Venkataraman

Abstract:

The creative journey in design often starts with a spark of inspiration, the source of which can be from myriad stimuli- nature, poetry, personal experiences or even fleeting thoughts and images. While it is indeed an important source of creative exploration, interpretation of this inspiration may often times be influenced by demographic and psychographic variables of the creator - Age, gender, lifecycle stage, personal experiences and individual personality traits being some of these factors. Common sources of inspiration can thus be interpreted differently, translating to different elements of design, and using varied principles in their execution. Do such variables in the creator influence the nature of the creative output? If yes, what are the visible matrices in the output which can be differentiated? An observational study with two groups of Design students, studying in the same design institute, under the guidance of the same design mentor, was conducted to map this influence. Both the groups were unaware of each other but worked with a common source of inspiration as provided by the instructor. In order to maintain congruence, both the groups were provided with lyrical compositions from well-known ballads and poetry as the source of their inspiration. The outputs were abstract renditions using lines, colors and shapes; and these were analyzed under matrices for the elements and principles used to create the compositions. The study indicated that there was a demarcation in terms of the choice of lines, colors and shapes chosen to create the composition, between both groups. The groups also tended to use repetition, proportion and emphasis differently; giving rise to varied uses of the Design principles. The study threw interesting observations on how Design interpretation can vary for the same source of inspiration, based on demographic and psychographic variances. The implications can be traced not just to the process of creative design, but also to the deep social roots that bind creative thinking and Design ideation; which can provide an interesting commentary between different cohorts on what constitutes ‘Good Design’.

Keywords: design compositions, inspiration, interpretation, psychographic factors, social factors

Procedia PDF Downloads 102

Authors: Mohammed Isah Shehu

Abstract:

This paper examined the context of globalization and Islam and accommodation or containment of one by the other. The paper is born out of the misconception and misunderstanding among many people that globalization is purely Western, anti-Islam and that Islam, globalization and Islam are diametrically opposed as such have no places for accommodating each other. The study used secondary sources to gather data. The study found that from its origin, Islam is in the whole context, a globalized religion and the contemporary globalization is already contained by Islam; that while contemporary globalization is centered on Western world, values and preferences (Western civilization, information and communication technology, free markets, trade and investments); some of the major foundation works that are aiding globalization were originally handiworks of past great Muslims (Islamic civilizations, Order of Algebra, tools of Navigation, Calligraphy, Medicine, Astronomy et cetera) whose major values are not Islamic; with globalization the Muslims have greater opportunities of spreading of Islam and practicing it in a most conducive atmosphere, easy and fast linkage with their fellow Muslim brothers wherever they may be; easier and freer world of trade and have the best opportunities to most things. The study however observed that Western contemporary globalization poses threats to religions such as those of globalization of immorality, injustice, trade with anti-Islamic terms and conditions, internationalized crime et cetera. Muslims would have to avoid or be cautious of many things for Islam is a complete religion that has what is forbidden and allowed (halaal and haramm) based on principles of (Shariah, justice to all, humanity and compassion, obedience to and seeking Allah’s pleasure); to Muslims, Contemporary globalization has to be in conformity with original provisions of Islam. The study recommended that Muslims must rise up in seeking knowledge on Islam and all other fields, further intellectual explorations of works by Muslim scholars/thinkers so that any advancement in globalization would be properly domesticated within Islam for the Muslims to make optimum use of any advancement to the benefit of Islam.

Keywords: accommodation, containment, Islam, globalization

Procedia PDF Downloads 261