Search results for: significant risk factors in megaprojects
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 27003

Search results for: significant risk factors in megaprojects

11583 Effect of Varying Zener-Hollomon Parameter (Temperature and Flow Stress) and Stress Relaxation on Creep Response of Hot Deformed AA3104 Can Body Stock

Authors: Oyindamola Kayode, Sarah George, Roberto Borrageiro, Mike Shirran

Abstract:

A phenomenon identified by our industrial partner has experienced sag on AA3104 can body stock (CBS) transfer bar during transportation of the slab from the breakdown mill to the finishing mill. Excessive sag results in bottom scuffing of the slab onto the roller table, resulting in surface defects on the final product. It has been found that increasing the strain rate on the breakdown mill final pass results in a slab resistant to sag. The creep response for materials hot deformed at different Zener–Holloman parameter values needs to be evaluated experimentally to gain better understanding of the operating mechanism. This study investigates this identified phenomenon through laboratory simulation of the breakdown mill conditions for various strain rates by utilizing the Gleeble at UCT Centre for Materials Engineering. The experiment will determine the creep response for a range of conditions as well as quantifying the associated material microstructure (sub-grain size, grain structure etc). The experimental matrices were determined based on experimental conditions approximate to industrial hot breakdown rolling and carried out on the Gleeble 3800 at the Centre for Materials Engineering, University of Cape Town. Plane strain compression samples were used for this series of tests at an applied load that allow for better contact and exaggerated creep displacement. A tantalum barrier layer was used for increased conductivity and decreased risk of anvil welding. One set of tests with no in-situ hold time was performed, where the samples were quenched after deformation. The samples were retained for microstructure analysis of the micrographs from the light microscopy (LM), quantitative data and images from scanning electron microscopy (SEM) and energy dispersive X-ray (EDX), sub-grain size and grain structure from electron back scattered diffraction (EBSD).

Keywords: aluminium alloy, can-body stock, hot rolling, creep response, Zener-Hollomon parameter

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11582 Investigation on The Feasibility of a Solar Desiccant Cooling System in Libya

Authors: A. S. Zgalei, B. T. Al-Mabrouk

Abstract:

With a particularly significant growth rate observed in the Libyan commercial and residential buildings coupled with a growth in energy demand, solar desiccant evaporative cooling offers energy savings and promises a good sharing for sustainable buildings where the availability of solar radiation matches with the cooling load demand. The paper presents a short introduction for the desiccant systems. A mathematical model of a selected system has been developed and a simulation has been performed in order to investigate the system performance at different working conditions and an optimum design of the system structure is established. The results showed a technical feasibility of the system working under the Libyan climatic conditions with a reasonable COP at temperatures that can be obtained through the solar reactivation system. Discussion of the results and the recommendations for future work are proposed.

Keywords: computer program, solar desiccant wheel cooling, system modelling, simulation, technical feasibility

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11581 Experiences of Social Participation among Community Elderly with Mild Cognitive Impairment: A Qualitative Research

Authors: Xue Li, Hui Xu

Abstract:

Mild cognitive impairment (MCI) is a clinical stage that occurs between normal aging and dementia. Although MCI increases the risk of developing dementia, individuals with MCI may maintain stable cognitive function and even recover to a typical cognitive state. An intervention to prevent or delay the progression to dementia in individuals with MCI may involve promoting social engagement. Social participation is the engagement in socially relevant social exchanges and meaningful activities. Older adults with MCI may encounter restricted cognitive abilities, mood changes, and behavioral difficulties during social participation, influencing their willingness to engage. Therefore, this study aims to employ qualitative research methods to gain an in-depth comprehension of the authentic social participation experiences of older adults with mild cognitive impairment, which will establish a foundation for designing appropriate intervention programs. A phenomenological research was conducted. The study participants were selected using the purposive sampling method in combination with the maximum differentiation sampling strategy. Face-to-face semistructured interviews were conducted among 12 elderly individuals suffering from mild cognitive impairment in a community in Zhengzhou City from May to July 2023. Colaizzi 7-step method was used to analyze the data and extract the theme. The real experience of social participation in older adults with mild cognitive impairment can be summarized into 3 themes: (1) a single social relationship but a strong desire to participate, (2) a dual experience of social participation with both positive and negative aspects, (3) multiple barriers to social participation, including impaired memory capacity, heavy family responsibilities and lack of infrastructure. The study found that elderly individuals with mild cognitive impairment and one social interaction display an increased desire to engage in society. To improve social participation levels and reduce cognitive function decline, healthcare providers should work with relevant government agencies and the community to create a comprehensive social participation system. It is important for healthcare providers to note the social participation status of the elderly with mild cognitive impairment.

Keywords: mild cognitive impairment, the elderly, social participation, qualitative research

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11580 Ground Effect on Marine Midge Water Surface Locomotion

Authors: Chih-Hua Wu, Bang-Fuh Chen, Keryea Soong

Abstract:

Midges can move on the surface of the water at speeds of approximately 340 body-lengths/s and can move continuously for >90 min. Their wings periodically scull the sea surface to push water backward and thus generate thrust; their other body parts, including their three pairs of legs, touch the water only occasionally. The aim of this study was to investigate the locomotion mechanism of marine midges with a size of 2 mm and living in shallow reefs in Wanliton, southern Taiwan. We assumed that midges generate lift through two mechanisms: by sculling the surface of seawater to leverage the generated tension for thrust and by retracting their wings to generate aerodynamic lift at a suitable angle of attack. We performed computational fluid dynamic simulations to determine the mechanism of midge locomotion above the surface of the water. The simulations indicated that ground effects are essential and that both the midge trunk and wing tips must be very close to the water surface to produce sufficient lift to keep the midge airborne. Furthermore, a high wing-beat frequency is crucial for the midge to produce sufficient lift during wing retraction. Accordingly, ground effects, forward speed, and high wing-beat frequency are major factors influencing the ability of midges to generate sufficient lift and remain airborne above the water surface.

Keywords: ground effect, water locomotion, CFD, aerodynamic lift

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11579 Optimization of Two Quality Characteristics in Injection Molding Processes via Taguchi Methodology

Authors: Joseph C. Chen, Venkata Karthik Jakka

Abstract:

The main objective of this research is to optimize tensile strength and dimensional accuracy in injection molding processes using Taguchi Parameter Design. An L16 orthogonal array (OA) is used in Taguchi experimental design with five control factors at four levels each and with non-controllable factor vibration. A total of 32 experiments were designed to obtain the optimal parameter setting for the process. The optimal parameters identified for the shrinkage are shot volume, 1.7 cubic inch (A4); mold term temperature, 130 ºF (B1); hold pressure, 3200 Psi (C4); injection speed, 0.61 inch3/sec (D2); and hold time of 14 seconds (E2). The optimal parameters identified for the tensile strength are shot volume, 1.7 cubic inch (A4); mold temperature, 160 ºF (B4); hold pressure, 3100 Psi (C3); injection speed, 0.69 inch3/sec (D4); and hold time of 14 seconds (E2). The Taguchi-based optimization framework was systematically and successfully implemented to obtain an adjusted optimal setting in this research. The mean shrinkage of the confirmation runs is 0.0031%, and the tensile strength value was found to be 3148.1 psi. Both outcomes are far better results from the baseline, and defects have been further reduced in injection molding processes.

Keywords: injection molding processes, taguchi parameter design, tensile strength, high-density polyethylene(HDPE)

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11578 Estimating Anthropometric Dimensions for Saudi Males Using Artificial Neural Networks

Authors: Waleed Basuliman

Abstract:

Anthropometric dimensions are considered one of the important factors when designing human-machine systems. In this study, the estimation of anthropometric dimensions has been improved by using Artificial Neural Network (ANN) model that is able to predict the anthropometric measurements of Saudi males in Riyadh City. A total of 1427 Saudi males aged 6 to 60 years participated in measuring 20 anthropometric dimensions. These anthropometric measurements are considered important for designing the work and life applications in Saudi Arabia. The data were collected during eight months from different locations in Riyadh City. Five of these dimensions were used as predictors variables (inputs) of the model, and the remaining 15 dimensions were set to be the measured variables (Model’s outcomes). The hidden layers varied during the structuring stage, and the best performance was achieved with the network structure 6-25-15. The results showed that the developed Neural Network model was able to estimate the body dimensions of Saudi male population in Riyadh City. The network's mean absolute percentage error (MAPE) and the root mean squared error (RMSE) were found to be 0.0348 and 3.225, respectively. These results were found less, and then better, than the errors found in the literature. Finally, the accuracy of the developed neural network was evaluated by comparing the predicted outcomes with regression model. The ANN model showed higher coefficient of determination (R2) between the predicted and actual dimensions than the regression model.

Keywords: artificial neural network, anthropometric measurements, back-propagation

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11577 Formulation, Acceptability, and Characteristics of Instant Surabi Based on Composite Rice-Soybean Flour and Supplemented with Torbangun Powder for Attention Deficit Hyperactivity Disorder Children

Authors: Dewi Hapsari Ratna Muninggar, M. Rizal Martua Damanik

Abstract:

The purpose of this study was to develop a formulation of instant Indonesian traditional pancake (Surabi) based on composite rice and soybean flour and supplemented with Torbangun (Coleus amboinicus Lour) powder as an alternative snack for ADHD (Attention Deficit Hyperactivity Disorder) children. Completely randomised factorial design by two factors which were the ratio of composite rice and soybean flour (75:25; 70:30; 65:35) as well as the addition of Torbangun powder (3%; 5%; 7%) was used in this study. This study revealed that the best formula was instant surabi with 65:35 composite rice and soybean flour and 5% addition of Torbangun powder by considering hedonic test result, functional aspect and nutrients contribution. Then, both chemical and physical characteristics from the best formula of instant surabi were measured. Nutrients content of the chosen instant surabi per 100 g wet basis were 62.68 g moisture, 1.30 g ash, 6.81 g protein, 0.75 g fat, 28.47 g carbohydrate, 88.62 mg calcium, 4.14 mg iron, and 144 kcal energy while physical characteristics, such as water activity, cohesiveness, and hardness were 0.97, 0.569, 5582.2 g force consecutively. The results of this research suggested that instant surabi which can be possibly beneficial for ADHD children had 65:35 for rice and soybean flour ratio as well as 5% for the addition of Torbangun powder.

Keywords: ADHD children, instant surabi, soybean, torbangun

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11576 Second-Order Slip Flow and Heat Transfer in a Long Isothermal Microchannel

Authors: Huei Chu Weng, Chien-Hung Liu

Abstract:

This paper presents a study on the effect of second-order slip and jump on forced convection through a long isothermally heated or cooled planar microchannel. The fully developed solutions of thermal flow fields are analytically obtained on the basis of the second-order Maxwell-Burnett slip and Smoluchowski jump boundary conditions. Results reveal that the second-order term in the Karniadakis slip boundary condition is found to contribute a negative velocity slip and then to lead to a higher pressure drop as well as a higher fluid temperature for the heated-wall case or to a lower fluid temperature for the cooled-wall case. These findings are contrary to predictions made by the Deissler model. In addition, the role of second-order slip becomes more significant when the Knudsen number increases.

Keywords: microfluidics, forced convection, gas rarefaction, second-order boundary conditions

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11575 Measurement of Turbulence with PITOT Static Tube in Low Speed Subsonic Wind Tunnel

Authors: Gopikrishnan, Bharathiraja, Boopalan, Jensin Joshua

Abstract:

The Pitot static tube has proven their values and practicability in measuring velocity of fluids for many years. With the aim of extensive usage of such Pitot tube systems, one of the major enabling technologies is to use the design and fabricate a high sensitive pitot tube for the purpose of calibration of the subsonic wind tunnel. Calibration of wind tunnel is carried out by using different instruments to measure variety of parameters. Using too many instruments inside the tunnel may not only affect the fluid flow but also lead to drag or losses. So, it is essential to replace the different system with a single system that would give all the required information. This model of high sensitive Pitot tube has been designed to ease the calibration process. It minimizes the use of different instruments and this single system is capable of calibrating the wind tunnel test section. This Pitot static tube is completely digitalized and so that the velocity data`s can be collected directly from the instrument. Since the turbulence factors are dependent on velocity, the data’s that are collected from the pitot static tube are then processed and the level of turbulence in the fluid flow is calculated. It is also capable of measuring the pressure distribution inside the wind tunnel and the flow angularity of the fluid. Thus, the well-designed high sensitive Pitot static tube is utilized in calibrating the tunnel and also for the measurement of turbulence.

Keywords: pitot static tube, turbulence, wind tunnel, velocity

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11574 Novel Ferroelectric Properties as Studied by Boson Mean Field Laser Radiation Induced from a Beer Bottle

Authors: Tadeus Atraskevic, Asch Dalbajobas, Mazahistas Pukuotukas

Abstract:

The novel ferroelectric properties appeared in the recent ten years. Many scientists consider them as non-statement science. Nevertheless, many papers are published. The Mean field theory takes an important place in the theory of ferroelectric materials which can be applied for Boson induced laser systems for ‘Star Track’ soldiers. The novel Laser, which was produced in The Vilnius Bambalio University is a ‘now-how’ among other laser systems. The laser can produce power of 30 kW during 15 seconds. Its size and compatibility distinguishes it among other devices and safety gadgets. Scientists of Bambalio University have already patented the device. The most interesting in this innovations is the process of operation. Merely it may be operated through a bottle a beer what makes the measurement so convenient, that an ordinary scientist can process all stuff without significant effort just by taking pleasure by drinking a bottle of beer. Here we would like to report on the laser system and present our unique developments.

Keywords: laser, boson, ferroelectrics, mean field theory

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11573 Grading Fourteen Zones of Isfahan in Terms of the Impact of Globalization on the Urban Fabric of the City, Using the TOPSIS Model

Authors: A. Zahedi Yeganeh, A. Khademolhosseini, R. Mokhtari Malekabadi

Abstract:

Undoubtedly one of the most far-reaching and controversial topics considered in the past few decades, has been globalization. Globalization lies in the essence of the modern culture. It is a complex and rapidly expanding network of links and mutual interdependence that is an aspect of modern life; though some argue that this link existed since the beginning of human history. If we consider globalization as a dynamic social process in which the geographical constraints governing the political, economic, social and cultural relationships have been undermined, it might not be possible to simply describe its impact on the urban fabric. But since in this phenomenon the increase in communications of societies (while preserving the main cultural - regional characteristics) with one another and the increase in the possibility of influencing other societies are discussed, the need for more studies will be felt. The main objective of this study is to grade based on some globalization factors on urban fabric applying the TOPSIS model. The research method is descriptive - analytical and survey. For data analysis, the TOPSIS model and SPSS software were used and the results of GIS software with fourteen cities are shown on the map. The results show that the process of being influenced by the globalization of the urban fabric of fourteen zones of Isfahan was not similar and there have been large differences in this respect between city zones; the most affected areas are zones 5, 6 and 9 of the municipality and the least impact has been on the zones 4 and 3 and 2.

Keywords: grading, globalization, urban fabric, 14 zones of Isfahan, TOPSIS model

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11572 Comparative Study of Sound Intensity in Individuals Diagnosed with Antisocial Personality Disorder and Normal People

Authors: Nadia Warmilee

Abstract:

This study is s descriptive-analytical research and it aims at studying sound intensity in individuals with antisocial personality disorder and ordinary persons. Data were collected from experimental and control groups by interviews and a field research. Population was all male Iranian with antisocial personality disorder that three of them (a murderer and two individuals with antisocial personality disorder (APD) who have not committed any crimes yet) were selected purposefully. They were compared to three non-affected people. PRAAT software has been used to analyze the data. Results of this study show that there is a significant relationship between dysthymia and sound intensity values. Antisocial personality disorder also affects sound intensity fluctuations. The values of sound intensity are higher in non-affected people than affected one whilst these values are more monotonous. T-test was used to study significance or in significance of sound intensity difference in producing vowels.

Keywords: Acoustics, Sound Intensity, Antisocial Personality Disorder, Psycholinguistics

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11571 Decoding the Structure of Multi-Agent System Communication: A Comparative Analysis of Protocols and Paradigms

Authors: Gulshad Azatova, Aleksandr Kapitonov, Natig Aminov

Abstract:

Multiagent systems have gained significant attention in various fields, such as robotics, autonomous vehicles, and distributed computing, where multiple agents cooperate and communicate to achieve complex tasks. Efficient communication among agents is a crucial aspect of these systems, as it directly impacts their overall performance and scalability. This scholarly work provides an exploration of essential communication elements and conducts a comparative assessment of diverse protocols utilized in multiagent systems. The emphasis lies in scrutinizing the strengths, weaknesses, and applicability of these protocols across various scenarios. The research also sheds light on emerging trends within communication protocols for multiagent systems, including the incorporation of machine learning methods and the adoption of blockchain-based solutions to ensure secure communication. These trends provide valuable insights into the evolving landscape of multiagent systems and their communication protocols.

Keywords: communication, multi-agent systems, protocols, consensus

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11570 A Review of Physiological Measures for Cognitive Workload Assessment of Aircrew

Authors: Naveed Tahir, Adnan Maqsood

Abstract:

Cognitive workload is a significant factor affecting user performance, and it has been broadly investigated for its application in ergonomics as well as in designing and optimizing effective human-machine interactions. It is mentally challenging to maneuver an aircraft, and pilots must control the aircraft and adequately communicate to the verbal-auditory stimuli. Several physiological measures have long been researched and used to demonstrate the cognitive workload. In our current study, we have summarized recent findings of the effectiveness, accuracy, and applicability of commonly used physiological measures in evaluating cognitive workload. We have also highlighted on the advancements in physiological measures. The strength and limitations of physiological measures have also been discussed to assess the cognitive workload of people, especially the aircrews in laboratory settings and real-time situations. We have presented the research findings of the physiological measures to base suggestions on the proper applications of the measures and settings demanding the use of single measure or their combinations.

Keywords: aircrew, cognitive workload, subjective measure, physiological measure, performance measure

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11569 Characteristic Components in Cornusofficinalis to AGEs Injury Protective Effect and Mechanism of HUVEC

Authors: Yu-Han Tao, Hui-Qin Xu

Abstract:

The present study aimed to explain the protective effect of Cornus officinalis characteristic components, under AGEs damage to HUVEC. After cultured HUVEC adhered, Cornus officinalis characteristic components such as loganin, morroniside, oleanolic acid, ursolic acid and aminoguanidine (positive control dug) hatched, after 1h the AGEs (200 mg/L) were added. After 24h, LDH, SOD, MDA, NO, ET, and AngⅡ, TGF-β, IL-1β, ROS in the supernatant were determined. The results showed the Cornus officinalis characteristic compounds could improve vitality of SOD, NO, reduce the MDA, ET, AngⅡ, TGF-β, IL-1β, ROS significantly when compared with the model groug. Loganin, oleanic acid, ursolic acid, had significant protective effect on AGEs injured HUVEC. As a conclusion, characteristic components in Cornus officinalis had a positive effect after HUVEC injured by AGEs.

Keywords: Cornus officinalis, morroniside, oganin, oleanolic acid, ursolic acid

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11568 Effect of Wolffia globosa Incorporation on the Physical, Phytochemical and Antioxidant Properties of Breadsticks

Authors: May Phyo Wai, Tanyawan Suantawee

Abstract:

The positive correlation between unhealthy diets (high in fats, sugars, carbohydrates, and low fibers) and the risk of non-communicable diseases (NCDs) like obesity, hypertension, diabetes, and heart diseases has led to a growing interest in healthier lifestyles and diets. Consequently, people are opting for foods rich in fiber and phytochemicals. Wolffia globosa, also known as duckweed or watermeal, is the smallest plant with high nutritional value, including protein, fiber, phytochemicals, and antioxidant properties. It offers numerous health benefits, such as improving gut health and lowering blood glucose levels, and it is widely available in Thailand. The purpose of this study was to develop nutritionally enhanced breadsticks utilizing vacuum heat-dried Wolffia globosa power (WP). Various concentrations of WP (0% as control, 5%, 10%, and 15 % w/w/) were added, and then the breadsticks’ physical properties (hardness, fracturability, and color), phytochemicals (total phenolic compounds: TPC and total flavonoid contents: TFC), and antioxidant properties (DPPH radical scavenging activity (DPPH) and ferric reducing antioxidant power (FRAP) assay) were investigated. Experiments were done by triplicates and data was analyzed by one-way ANOVA. The results showed that the hardness, measured by a texture analyzer, increased significantly (p<0.05) with higher WP concentrations, reaching 2,897.01 ± 77.31 g at 15% WP from 1,314.41 ± 32.52 g of the control. In contrast, the lightness (L*), redness (a*), and yellowness (b*) of the breadsticks significantly decreased (p < 0.05) in a dose-dependent manner with added WP. Incorporating WP, rich in phytochemicals and antioxidants, into the flour significantly enhanced the TPC and TFC of the breadsticks (p<0.05), with TPC and TFC increasing dose-dependently rising to 1.8-fold and 3.5-fold at 15% WP, respectively. The antioxidant power, assessed by DPPH and FRAP assays, also showed a similar trend, with significantly higher values at 10% and 15% WP (p<0.05). These results indicate that adding WP significantly boosted the TPC, TFC, DPPH, and FRAP values of the developed breadsticks. Therefore, incorporating WP into breadsticks might be a promising strategy for creating food products enriched with phytochemicals and antioxidants, offering consumers healthier options in the market.

Keywords: antioxidant properties, breadsticks, phytochemicals, Wolffia globosa

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11567 Impact of Schools' Open and Semi-Open Spaces on Student's Studying Behavior

Authors: Chaithanya Pothuganti

Abstract:

Open and semi-open spaces in educational buildings like corridors, mid landings, seating spaces, lobby, courtyards are traditionally have been the places of social communion and interaction which helps in promoting the knowledge, performance, activeness, and motivation in students. Factors like availability of land, commercialization, of educational facilities, especially in e-techno and smart schools, led to closed classrooms to accommodate students thereby lack quality open and semi-open spaces. This insufficient attention towards open space design which is a means of informal learning misses an opportunity to encourage the student’s skill development, behavior and learning skills. The core objective of this paper is to find the level of impact on student learning behavior and to identify the suitable proportions and configuration of spaces that shape the schools. In order to achieve this, different types of open spaces in schools and their impact on student’s performance in various existing models are analysed using case studies to draw some design principles. The study is limited to indoor open spaces like corridors, break out spaces and courtyards. The expected outcome of the paper is to suggest better design considerations for the development of semi-open and open spaces which functions as an element for informal learnings. Its focus is to provide further thinking on designing and development of open spaces in educational buildings.

Keywords: configuration of spaces and proportions, informal learning, open spaces, schools, student’s behavior

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11566 Analytical Solutions of Time Space Fractional, Advection-Dispersion and Whitham-Broer-Kaup Equations

Authors: Muhammad Danish Khan, Imran Naeem, Mudassar Imran

Abstract:

In this article, we study time-space Fractional Advection-Dispersion (FADE) equation and time-space Fractional Whitham-Broer-Kaup (FWBK) equation that have a significant role in hydrology. We introduce suitable transformations to convert fractional order derivatives to integer order derivatives and as a result these equations transform into Partial Differential Equations (PDEs). Then the Lie symmetries and corresponding optimal systems of the resulting PDEs are derived. The symmetry reductions and exact independent solutions based on optimal system are investigated which constitute the exact solutions of original fractional differential equations.

Keywords: modified Riemann-Liouville fractional derivative, lie-symmetries, optimal system, invariant solutions

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11565 Impact of the Energy Transition on Security of Supply - A Case Study of Vietnam Power System in 2030

Authors: Phuong Nguyen, Trung Tran

Abstract:

Along with the global ongoing energy transition, Vietnam has indicated a strong commitment in the last COP events on the zero-carbon emission target. However, it is a real challenge for the nation to replace fossil-fired power plants by a significant amount of renewable energy sources (RES) while maintaining security of supply. The unpredictability and variability of RES would cause technical issues for supply-demand balancing, network congestions, system balancing, among others. It is crucial to take these into account while planning the future grid infrastructure. This study will address both generation and transmission adequacy and reveal a comprehensive analysis about the impact of ongoing energy transition on the development of Vietnam power system in 2030. This will provide insight for creating an secure, stable, and affordable pathway for the country in upcoming years.

Keywords: generation adequacy, transmission adequacy, security of supply, energy transition

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11564 A Qualitative Examination of the Impact of COVID-19 on the Wellbeing of Undergraduate Students in Ontario

Authors: Soumya Mishra, Elena Neiterman

Abstract:

Aligned with the growing interest in the impact of the pandemic on academic experiences of university students, this study aimed to examine the challenges Canadian undergraduate students experienced during the university closures due to COVID-19. Using qualitative methodological approach, the study utilized semi-structured interviews conducted with 20 undergraduate students enrolled in an Ontario university to explore their thoughts and experience regarding online learning during the peak of the COVID-19 pandemic, from January 2021 to March 2021. The interviews yielded four major themes with the following associated subthemes: Personal Challenges Associated with Adapting to the Pandemic (Change in the Type of Stress Experienced, Unique Impact on Certain Groups of Students, Decreased Motivation, Crucial Role of Resilience), Social Challenges Associated with Adapting to the Pandemic (Increased Loneliness, Challenges Faced while Communicating, Perception of Group work, Role of Living Conditions), Challenges associated with Accessing University Resources (Crucial Role of Professors, Perception of Virtual Events, Importance of Physical Spaces). Overall, the analysis showed that the COVID-19 pandemic fostered resilience and psychological flexibility amongst all students. However, the mental health and social wellbeing of students deteriorated during the COVID-19 pandemic and they reported experiencing chronic stress, anxiety and loneliness. International students, first year and final year students experienced a unique set of challenges. It was hard for participants in our study to make strong new connections with their classmates and maintain existing friendships with their peers. The importance of professors in facilitating learning was amplified in the online environment due to the lack of in-person interaction with other students. Despite these challenges, most participants reported that they received high grades during online learning. The findings from this study could be helpful for organizations and individuals working towards fostering the wellbeing of undergraduate students. They can also help in making post-secondary institutions more resilient to future emergencies by creating contingency plans regarding online instructions and risk management techniques.

Keywords: Canadian, COVID-19, university students, wellbeing

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11563 Mongolian Water Quality Problem and Health of Free-Grazing Sheep

Authors: Yu Yoshihara, Chika Tada, Moe Takada, Nyam-Osor Purevdorj, Khorolmaa Chimedtseren, Yutaka Nakai

Abstract:

Water pollution from animal waste and its influence on grazing animals is a current concern regarding Mongolian grazing lands. We allocated 32 free-grazing lambs to four groups and provided each with water from a different source (upper stream, lower stream, well, and pond) for 49 days. We recorded the amount of water consumed by the lambs, as well as their body weight, behavior, white blood cell count, acute phase (haptoglobin) protein level, and fecal condition. We measured the chemical and biological qualities of the four types of water, and we detected enteropathogenic and enterohemorrhagic Escherichia coli in fecal samples by using a genetic approach. Pond water contained high levels of nitrogen and minerals, and well water contained high levels of bacteria. The odor concentration index decreased in order from pond water to upper stream, lower stream, and well. On day 15 of the experiment, the following parameters were the highest in lambs drinking water from the following sources: water intake (pond or lower stream), body weight gain (pond), WBC count (lower stream), haptoglobin concentration (well), and enteropathogenic E. coli infection rate (lower stream). Lambs that drank well water spent more time lying down and less time grazing than the others, and lambs that drank pond water spent more time standing and less time lying down. Lambs given upper or lower stream water exhibited more severe diarrhea on day 15 of the experiment than before the experiment. Mongolian sheep seemed to adapt to chemically contaminated water: their productivity benefited the most from pond water, likely owing to its rich mineral content. Lambs that drank lower stream water showed increases in enteropathogenic E. coli infection, clinical diarrhea, and WBC count. Lambs that drank well water, which was bacteriologically contaminated, had increased serum acute phase protein levels and poor physical condition; they were thus at increased risk of negative health and production effects.

Keywords: DNA, Escherichia coli, fecal sample, lower stream, well water

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11562 Impact of Population Size on Symmetric Travelling Salesman Problem Efficiency

Authors: Wafa' Alsharafat, Suhila Farhan Abu-Owida

Abstract:

Genetic algorithm (GA) is a powerful evolutionary searching technique that is used successfully to solve and optimize problems in different research areas. Genetic Algorithm (GA) considered as one of optimization methods used to solve Travel salesman Problem (TSP). The feasibility of GA in finding a TSP solution is dependent on GA operators; encoding method, population size, termination criteria, in general. In specific, crossover and its probability play a significant role in finding possible solutions for Symmetric TSP (STSP). In addition, the crossover should be determined and enhanced in term reaching optimal or at least near optimal. In this paper, we spot the light on using a modified crossover method called modified sequential constructive crossover and its impact on reaching optimal solution. To justify the relevance of a parameter value in solving the TSP, a set comparative analysis conducted on different crossover methods values.

Keywords: genetic algorithm, crossover, mutation, TSP

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11561 Settlement Performance of Granular Column Reinforced Soil

Authors: Muneerah Jeludin

Abstract:

The vibrated column has been widely used over the last three decades to improve the performance of soft ground and engineered compacted fill. The main reason for adopting this technique is that it is economically viable and environmental friendly. The performance of granular column with regards to bearing capacity has been well documented; however, information regarding the settlement behavior of granular columns is still limited. This paper aims to address the findings from a laboratory model study in terms of its settlement improvement. A 300 mm diameter and 400 mm high kaolin clay model was used in this investigation. Columns of various heights were installed in the clay bed using replacement method. The results in relation to load sharing mechanism between the column and surrounding clay just under the footing indicated that in short column, the available shaft resistance was not significant and introduces a potential for end braing failure as opposed to bulging failure in long columns. The settlement improvement factor corroborates well with field observations.

Keywords: ground improvement, model test, reinforced soil, foundation

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11560 Effect of Elastic Modulus Varieties on Helical Pile Behavior in Sand

Authors: Javad Shamsi Soosahab, Reza Ziaie Moayed

Abstract:

The compressive and tensile bearing capacity of helical piles in sand is investigated by means of numerical modeling. The analyses are carried out using two-dimensional finite-element software, Optum G2. The load–displacement behavior under compression and tension is compared in different relative densities for constant and various elastic modulus. The criterion used to find the ultimate axial load is the load corresponding to 5% of the helical diameter. The results show that relative density of sand plays an essential role in the response of ultimate capacities towards various condition. Increase in elastic modulus with depth is found to play a relatively more significant role to the increase in ultimate compressive load capacities, however tension bearing capacity decreases.

Keywords: helical piles, Optum G2, relative density, constant and various elastic modulus

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11559 Mitigation of Offshore Piling Noise Effects on Marine Mammals

Authors: Waled A. Dawoud, Abdelazim M. Negm, Nasser M. Saleh

Abstract:

Offshore piling generates underwater sound at level high enough to cause physical damage or hearing impairment to the marine mammals. Several methods can be used to mitigate the effect of underwater noise from offshore pile driving on marine mammals which can be divided into three main approaches. The first approach is to keep the mammal out of the high-risk area by using aversive sound waves produced by acoustic mitigation devices such as playing-back of mammal's natural predator vocalization, alarm or distress sounds, and anthropogenic sound. The second approach is to reduce the amount of underwater noise from pile driving using noise mitigation techniques such as bubble curtains, isolation casing, and hydro-sound dampers. The third approach is to eliminate the overlap of underwater waves by using prolonged construction process. To investigate the effectiveness of different noise mitigation methods; a pile driven with 235 kJ rated energy diesel hammer near Jeddah Coast, Kingdom of Saudi Arabia was used. Using empirical sound exposure model based on Red Sea characteristics and limits of National Oceanic and Atmospheric Administration; it was found that the aversive sound waves should extend to 1.8 km around the pile location. Bubble curtains can reduce the behavioral disturbance area up to 28%; temporary threshold shift up to 36%; permanent threshold shift up to 50%; and physical injury up to 70%. Isolation casing can reduce the behavioral disturbance range up to 12%; temporary threshold shift up to 21%; permanent threshold shift up to 29%; and physical injury up to 46%. Hydro-sound dampers efficiency depends mainly on the used technology and it can reduce the behavioral disturbance range from 10% to 33%; temporary threshold shift from 18% to 25%; permanent threshold shift from 32% to 50%; and physical injury from 46% to 60%. To prolong the construction process, it was found that the single pile construction, use of soft start, and keep time between two successive hammer strikes more than 3 seconds are the most effective techniques.

Keywords: offshore pile driving, sound propagation models, noise effects on marine mammals, Underwater noise mitigation

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11558 Anti-Western Sentiment amongst Arabs and How It Drives Support for Russia against Ukraine

Authors: Soran Tarkhani

Abstract:

A glance at social media shows that Russia's invasion of Ukraine receives considerable support among Arabs. This significant support for the Russian invasion of Ukraine is puzzling since most Arab leaders openly condemned the Russian invasion through the UN ES‑11/4 Resolution, and Arabs are among the first who experienced the devastating consequences of war firsthand. This article tries to answer this question by using multiple regression to analyze the online content of Arab responses to Russia's invasion of Ukraine on seven major news networks: CNN Arabic, BBC Arabic, Sky News Arabic, France24 Arabic, DW, Aljazeera, and Al-Arabiya. The article argues that the underlying reason for this Arab support is a reaction to the common anti-Western sentiments among Arabs. The empirical result from regression analysis supports the central arguments and uncovers the motivations behind the endorsement of the Russian invasion of Ukraine and the opposing Ukraine by many Arabs.

Keywords: Ukraine, Russia, Arabs, Ukrainians, Russians, Putin, invasion, Europe, war

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11557 Fluctuation of Serum Creatinine: Preoperative and Postoperative Evaluation of Chronic Kidney Disease Patients

Authors: Chowdhury Md. Navim Kabir

Abstract:

Renal impairment is one of the most severe non-communicable diseases around the world. Especially patients with diagnosed/newly diagnosed renal impairment who need surgery are more focused on preoperative and postoperative preparation. Serum creatinine is the prime biochemical marker for assessing renal function, and the level of impairment is widely measured by this marker as well as Glomerular Filtration Rate (GFR). Objective: Factors responsible for fluctuating serum creatinine during preoperative and postoperative periods and minimizing the process of serum creatinine is the ultimate goal of this study. Method: 37 patients participated in this cross-sectional study who were previously diagnosed/newly diagnosed. They were admitted to different tertiary-level hospitals for emergency or elective surgery. Fifteen patients were admitted in the renal function impairment stage and 22 were admitted as normal patients’. Values of creatinine at the pre-admission stage and 2nd/3rd post-admission follow-up were compared. Results: 0.41 was the average of 22 patients' creatinine between pre-admission and 2nd/3rd follow-up. The responsible factor like prolonged staying, immobilization, co-morbidities, different preoperative antibiotics and Non-Steroidal Anti Inflammatory Drugs (NSAIDs) were also inducers for creatinine elevation. After postoperative hemodialysis rapid decrease of creatinine is seen in normal patients, but this decrease is very much minor in Chronic Kidney Disease (CKD) diagnosed patients.

Keywords: CKD, Meropenam, NSAID, comorbidities, immobilized

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11556 Bridging the Gap through New Media Technology Acceptance: Exploring Chinese Family Business Culture

Authors: Farzana Sharmin, Mohammad Tipu Sultan

Abstract:

Emerging new media technology such as social media and social networking sites have changed the family business dynamics in Eastern Asia. The family business trends in China has been developed at an exponential rate towards technology. In the last two decades, many of this family business has succeeded in becoming major players in the Chinese and world economy. But there are a very few availabilities of literature on Chinese context regarding social media acceptance in terms of the family business. Therefore, this study has tried to cover the gap between culture and new media technology to understand the attitude of Chinese young entrepreneurs’ towards the family business. This paper focused on two cultural dimensions (collectivism, long-term orientation), which are adopted from Greet Hofstede’s. Additionally perceived usefulness and ease of use adopted from the Technology Acceptance Model (TAM) to explore the actual behavior of technology acceptance for the family business. A quantitative survey method (n=275) used to collect data Chinese family business owners' in Shanghai. The inferential statistical analysis was applied to extract trait factors, and verification of the model, respectively. The research results found that using social media for family business promotion has highly influenced by cultural values (collectivism and long-term orientation). The theoretical contribution of this research may also assist policymakers and practitioners of other developing countries to advertise and promote the family business through social media.

Keywords: China, cultural dimensions, family business, technology acceptance model, TAM

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11555 Nonlinear Flow Behavior and Validity of the Cubic Law in a Rough Fracture

Authors: Kunwar Mrityunjai Sharma, Trilok Nath Singh

Abstract:

The Navier-Stokes equation is used to study nonlinear fluid flow in rough 2D fractures. The major goal is to investigate the influence of inertial flow owing to fracture wall roughness on nonlinear flow behavior. Roughness profiles are developed using Barton's Joint Roughness Coefficient (JRC) and used as fracture walls to assess wall roughness. Four JRC profiles (5, 11, 15, and 19) are employed in the study, where a higher number indicates higher roughness. A parametric study has been performed using varying pressure gradients, and the corresponding Forchheimer number is calculated to observe the nonlinear behavior. The results indicate that the fracture roughness has a significant effect on the onset of nonlinearity. Additionally, the validity of the cubic law is evaluated and observed that it overestimates the flow in rough fractures and should be used with utmost care.

Keywords: fracture flow, nonlinear flow, cubic law, Navier-stokes equation

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11554 Semantic Differences between Bug Labeling of Different Repositories via Machine Learning

Authors: Pooja Khanal, Huaming Zhang

Abstract:

Labeling of issues/bugs, also known as bug classification, plays a vital role in software engineering. Some known labels/classes of bugs are 'User Interface', 'Security', and 'API'. Most of the time, when a reporter reports a bug, they try to assign some predefined label to it. Those issues are reported for a project, and each project is a repository in GitHub/GitLab, which contains multiple issues. There are many software project repositories -ranging from individual projects to commercial projects. The labels assigned for different repositories may be dependent on various factors like human instinct, generalization of labels, label assignment policy followed by the reporter, etc. While the reporter of the issue may instinctively give that issue a label, another person reporting the same issue may label it differently. This way, it is not known mathematically if a label in one repository is similar or different to the label in another repository. Hence, the primary goal of this research is to find the semantic differences between bug labeling of different repositories via machine learning. Independent optimal classifiers for individual repositories are built first using the text features from the reported issues. The optimal classifiers may include a combination of multiple classifiers stacked together. Then, those classifiers are used to cross-test other repositories which leads the result to be deduced mathematically. The produce of this ongoing research includes a formalized open-source GitHub issues database that is used to deduce the similarity of the labels pertaining to the different repositories.

Keywords: bug classification, bug labels, GitHub issues, semantic differences

Procedia PDF Downloads 190