Search results for: respiratory rate

Authors: Nadia Sghaier

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In this paper, we aim to identify the determinants of the life and non-life insurance premiums of different lines for the case of the Tunisian insurance market over a recent period from 1997 to 2019. The empirical analysis is conducted using the linear cointegration techniques in the panel data framework, which allow both long and short-run relationships. The obtained results show evidence of long-run relationship between premiums, losses, and financial variables (stock market indices and interest rate). Furthermore, we find that the short-run effect of explanatory variables differs across lines. This finding has important implications for insurance tarification and regulation.

Keywords: insurance premiums, lines, Tunisian insurance market, cointegration approach in panel data

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Authors: Jyoti Singh, Ranju Bansal

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Fighting pain and inflammation is a common problem faced by physicians while dealing with a wide variety of diseases. Since ancient time nonsteroidal anti-inflammatory agents (NSAIDs) and opioids have been the cornerstone of treatment therapy, however, the usefulness of both these classes is limited due to severe side effects. NSAIDs, which are mainly used to treat mild to moderate inflammatory pain, induce gastric irritation and nephrotoxicity whereas opioids show an array of adverse reactions such as respiratory depression, sedation, and constipation. Moreover, repeated administration of these drugs induces tolerance to the analgesic effects and physical dependence. Further discovery of selective COX-2 inhibitors (coxibs) suggested safety without any ulcerogenic side effects; however, long-term use of these drugs resulted in kidney and hepatic toxicity along with an increased risk of secondary cardiovascular effects. The basic approaches towards inflammation and pain treatment are constantly changing, and researchers are continuously trying to develop safer and effective anti-inflammatory drug candidates for the treatment of different inflammatory conditions such as osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, psoriasis and multiple sclerosis. Synthetic 3(2H)-pyridazinones constitute an important scaffold for drug discovery. Structure-activity relationship studies on pyridazinones have shown that attachment of a lactam at N-2 of the pyridazinone ring through a methylene spacer results in significantly increased anti-inflammatory and analgesic properties of the derivatives. Further introduction of the heterocyclic ring at lactam nitrogen results in improvement of biological activities. Keeping in mind these SAR studies, a new series of compounds were synthesized as shown in scheme 1 and investigated for anti-inflammatory, analgesic, anti-platelet activities and docking studies. The structures of newly synthesized compounds have been established by various spectroscopic techniques. All the synthesized pyridazinone derivatives exhibited potent anti-inflammatory and analgesic activity. Homoveratryl substituted derivative was found to possess highest anti-inflammatory and analgesic activity displaying 73.60 % inhibition of edema at 40 mg/kg with no ulcerogenic activity when compared to standard drugs indomethacin. Moreover, 2-substituted-4-benzo[d][1,3]dioxole-6-phenylpyridazin-3(2H)-ones derivatives did not produce significant changes in bleeding time and emerged as safe agents. Molecular docking studies also illustrated good binding interactions at the active site of the cyclooxygenase-2 (hCox-2) enzyme.

Keywords: anti-inflammatory, analgesic, pyridazin-3(2H)-one, selective COX-2 inhibitors

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Authors: Oluwafunmibi Omotayo Fasanya, Augustine Kena Adjei

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Physiological changes during pregnancy, such as alterations in the circulatory, respiratory, and musculoskeletal systems, can negatively impact daily physical activity. This reduced activity is often associated with an increased risk of adverse maternal health outcomes, particularly gestational diabetes mellitus (GDM) and excessive weight gain. This meta-analysis aims to evaluate the effectiveness of structured physical exercise interventions during pregnancy in reducing the risk of GDM and managing maternal weight gain. A comprehensive search was conducted across six major databases: PubMed, Cochrane Library, EMBASE, Web of Science, ScienceDirect, and ClinicalTrials.gov, covering the period from database inception until 2023. Randomized controlled trials (RCTs) that explored the effects of physical exercise programs on pregnant women with low physical activity levels were included. The search was performed using EndNote and results were managed using RevMan (Review Manager) for meta-analysis. RCTs involving healthy pregnant women with low levels of physical activity or sedentary lifestyles were selected. These RCTs must have incorporated structured exercise programs during pregnancy and reported on outcomes related to GDM and maternal weight gain. From an initial pool of 5,112 articles, 65 RCTs (involving 11,400 pregnant women) met the inclusion criteria. Data extraction was performed, followed by a quality assessment of the selected studies using the Cochrane Risk of Bias tool. The meta-analysis was conducted using RevMan software, where pooled relative risks (RR) and weighted mean differences (WMD) were calculated using a random-effects model to address heterogeneity across studies. Sensitivity analyses, subgroup analyses (based on factors such as exercise intensity, duration, and pregnancy stage), and publication bias assessments were also conducted. Structured physical exercise during pregnancy led to a significant reduction in the risk of developing GDM (RR = 0.68; P < 0.001), particularly when the exercise program was performed throughout the pregnancy (RR = 0.62; P = 0.035). In addition, maternal weight gain was significantly reduced (WMD = −1.18 kg; 95% CI −1.54 to −0.85; P < 0.001). There were no significant adverse effects reported for either the mother or the neonate, confirming that exercise interventions are safe for both. This meta-analysis highlights the positive impact of regular moderate physical activity during pregnancy in reducing the risk of GDM and managing maternal weight gain. These findings suggest that physical exercise should be encouraged as a routine part of prenatal care. However, more research is required to refine exercise recommendations and determine the most effective interventions based on individual risk factors and pregnancy stages.

Keywords: gestational diabetes, maternal weight management, meta-analysis, randomized controlled trials

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Authors: A. H. Meysami

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In this paper, the hot compression tests were carried on X45CrNiW189 valve steel (X45) in the temperature range of 1000–1200°C and the strain rate range of 0.004–0.5 s^(-1) in order to study the high temperature softening behavior of the steel. For the exact prediction of flow stress, the effective stress - effective strain curves were obtained from experiments under various conditions. On the basis of experimental results, the dynamic recrystallization fraction (DRX), AGS, hot deformation and activation energy behavior were investigated. It was found that the calculated results were in a good agreement with the experimental flow stress and microstructure of the steel for different conditions of hot deformation.

Keywords: X45CrNiW189, valve steel, hot compression test, dynamic recrystallization, hot deformation

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Authors: Abdulnasir Hossen, Alaa Barhoum, Deepali Jaju, V. Gowri, L. Al-Kharusi, M. Hassan, K. Al-Hashmi

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Preeclampsia is a pregnancy disorder associated with increase in blood pressure and excess amount of protein in the urine. HRV analysis has been used by many researchers to identify preeclamptic pregnancy from normal pregnancy. A study in this regard to identify preeclamptic pregnancy in Oman from normal pregnant was conducted on 40 subjects (20 patients and 20 normal). The subjects were collected from two hospitals in Oman. A Fast Fourier transform (FFT) spectral analysis has shown that patients with preeclamptic pregnancy have a reduction in the power of the HF band and an increase in the power of the LF band of HRV compared with subjects with normal pregnancy. The accuracy of identification obtained was 80%.

Keywords: preelampsia, pregnancy hypertension, normal pregnant, FFT, spectral analysis, HRV

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Authors: Aisling Davies, Ciara Greene

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Over the past decade the phenomenon of mind-wandering in cognitive tasks has attracted widespread scientific attention. Research indicates that mind-wandering occurrences can be detected through behavioural responses in the Sustained Attention to Response Task (SART) and several studies have attributed a specific pattern of responding around an error in this task to an observable effect of a mind-wandering state. SART behavioural responses are also widely accepted as indices of sustained attention and of general attention lapses. However, evidence suggests that these same patterns of responding may be attributable to other factors associated with more focused states and that it may also be possible to distinguish the two states within the same task. To use behavioural responses in the SART to study mind-wandering, it is essential to establish both the SART parameters that would increase the likelihood of errors due to mind-wandering, and exactly what type of responses are indicative of mind-wandering, neither of which have yet been determined. The aims of this study were to compare different versions of the SART to establish which task would induce the most mind-wandering episodes and to determine whether mind-wandering related errors can be distinguished from errors during periods of focus, by behavioural responses in the SART. To achieve these objectives, 25 Participants completed four modified versions of the SART that differed from the classic paradigm in several ways so to capture more instances of mind-wandering. The duration that trials were presented for was increased proportionately across each of the four versions of the task; Standard, Medium Slow, Slow, and Very Slow and participants intermittently responded to thought probes assessing their level of focus and degree of mind-wandering throughout. Error rates, reaction times and variability in reaction times decreased in proportion to the decrease in trial duration rate and the proportion of mind-wandering related errors increased, until the Very Slow condition where the extra decrease in duration no longer had an effect. Distinct reaction time patterns around an error, dependent on level of focus (high/low) and level of mind-wandering (high/low) were also observed indicating four separate attention states occurring within the SART. This study establishes the optimal duration of trial presentation for inducing mind-wandering in the SART, provides evidence supporting the idea that different attention states can be observed within the SART and highlights the importance of addressing other factors contributing to behavioural responses when studying mind-wandering during this task. A notable finding in relation to the standard SART, was that while more errors were observed in this version of the task, most of these errors were during periods of focus, raising significant questions about our current understanding of mind-wandering and associated failures of attention.

Keywords: attention, mind-wandering, trial duration rate, Sustained Attention to Response Task (SART)

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Authors: Alsahli Abdulaziz Abdullah, Hameed Ullah Khan

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Software development nowadays is more and more using global ways of development instead of normal development enviroment where development occur in one location. This paper is a aimed to propose a Requirement Engineering framework to support Global Software Development environment with regards to all requirment engineering activities from elicitation to fially magning requirment change. Global software enviroment is more and more gaining better reputation in software developmet with better quality is resulting from developing in this eviroment yet with lower cost.However, failure rate developing in this enviroment is high due to inapproprate requirment development and managment.This paper will add to the software engineering development envrioments discipline and many developers in GSD will benefit from it.

Keywords: global software development environment, GSD, requirement engineering, FreGsd, computer engineering

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Authors: Era Dorihi Kale, Sabina Gero, Uly Agustine

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Asylum seekers are people who come to other countries to get asylum. In line with that, they also carry the culture and health behavior of their country, which is very different from the new country they currently live in. This situation raises problems, also in the health sector. The approach taken must also be a culturally sensitive approach, where the culture and habits of the refugee's home area are also valued so that the health services provided can be right on target. Some risk factors that already exist in this group are lack of activity, consumption of fast food, smoking, and stress levels that are quite high. Overall this condition will increase the risk of an increased incidence of cardiovascular disease. This research is a descriptive and experimental study. The purpose of this study is to identify health status and develop a culturally sensitive health promotion model, especially related to the risk of cardiovascular disease for asylum seekers in detention homes in the city of Kupang. This research was carried out in 3 stages, stage 1 was conducting a survey of health problems and the risk of asylum seeker cardiovascular disease, Stage 2 developed a health promotion model, and stage 3 conducted a testing model of health promotion carried out. There were 81 respondents involved in this study. The variables measured were: health status, risk of cardiovascular disease and, health promotion models. Method of data collection: Instruments (questionnaires) were distributed to respondents answered for anamnese health status; then, cardiovascular risk measurements were taken. After that, the preparation of information needs and the compilation of booklets on the prevention of cardiovascular disease is carried out. The compiled booklet was then translated into Farsi. After that, the booklet was tested. Respondent characteristics: average lived in Indonesia for 4.38 years, the majority were male (90.1%), and most were aged 15-34 years (90.1%). There are several diseases that are often suffered by asylum seekers, namely: gastritis, headaches, diarrhea, acute respiratory infections, skin allergies, sore throat, cough, and depression. The level of risk for asylum seekers experiencing cardiovascular problems is 4 high risk people, 6 moderate risk people, and 71 low risk people. This condition needs special attention because the number of people at risk is quite high when compared to the age group of refugees. This is very related to the level of stress experienced by the refugees. The health promotion model that can be used is the transactional stress and coping model, using Persian (oral) and English for written information. It is recommended for health practitioners who care for refugees to always pay attention to aspects of culture (especially language) as well as the psychological condition of asylum seekers to make it easier to conduct health care and promotion. As well for further research, it is recommended to conduct research, especially relating to the effect of psychological stress on the risk of cardiovascular disease in asylum seekers.

Keywords: asylum seekers, health status, cardiovascular disease, health promotion

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Authors: Ella Abaev, Shany Segal, Miri Gabay

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Background: Choking is a blockage of airways that prevents efficient breathing and air flow to the lungs. Choking may be partial or full and is an emergency situation. Complete or prolonged choking leads to apnea, lack of oxygen in the tissues of the body and brain, and can cause death. There are three mechanisms of choking: obstruction of internal respiratory tracts by food or object aspiration, any material that blocks or covers external air passages, external pressure on the neck or trapping between objects. Children's airways are narrower than that of adults and therefore the risk of choking is greater, due to the aspiration of food and other foreign bodies into the lungs. In the Child Development Center at Safra Children’s Hospital, Tel Hashomer in Israel are treated infants, toddlers, and children aged 0-18 years with various developmental disabilities. Due to the increase in reports of ‘almost an event’ of choking in the past year and the serious consequences of choking event, it was decided to give an emphasis to the issue. Incidence and methods: The number of reports of ‘almost an event’ or a choking event was examined at the center during the years 2013-2018 and a thorough research work was conducted on the subject in order to build a prevention program. Findings: Between 2013 and 2018 the center reported about ten cases of ‘almost choking events’. In the middle of 2018 alone three cases of ‘almost an event’ were reported. Objective: Providing knowledge leads to awareness raise, change of perception, change in behavior and prevention. The center employs more than 130 staff members from various sectors so that it is the work of multi-professional teams to promote the quality and safety of the treatment. The familiarity of the staff with risk factors, prevention guidelines, identification of choking signs, and treatment are most important and significant in determining the outcome of a choking event. Conclusions and recommendations: After in-depth research work was carried out in cooperation with the Risk Management Unit on the subject of choking, which include a description of the definitions, mechanisms, risk factors, treatment methods and extensive recommendations for prevention (e.g. using treatment and stimulation accessories with standards association stamps and adjustment of the type of food and the way it is served to match to the child's age and the ability to swallow). The expected stages of development and emphasis on the population of children with special needs were taken into account. The research findings will be published by the staff and parents of the patients, professional publications, and lectures and there is an expectation to decrease the number of choking events in the next years.

Keywords: children with special needs, choking, educational system, prevention guidelines

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Authors: Amir Gharavi, Mohamed Hassan, Amjad Shah

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The main characteristics of unconventional reservoirs include low-to ultra low permeability and low-to-moderate porosity. As a result, hydrocarbon production from these reservoirs requires different extraction technologies than from conventional resources. An unconventional reservoir must be stimulated to produce hydrocarbons at an acceptable flow rate to recover commercial quantities of hydrocarbons. Permeability for unconventional reservoirs is mostly below 0.1 mD, and reservoirs with permeability above 0.1 mD are generally considered to be conventional. The hydrocarbon held in these formations naturally will not move towards producing wells at economic rates without aid from hydraulic fracturing which is the only technique to assess these tight reservoir productions. Horizontal well with multi-stage fracking is the key technique to maximize stimulated reservoir volume and achieve commercial production. The main objective of this research paper is to investigate development options for a tight mature oilfield. This includes multistage hydraulic fracturing and spacing by building of reservoir models in the Reveal simulator to model potential development options based on sidetracking the existing vertical well. To simulate potential options, reservoir models have been built in the Reveal. An existing Petrel geological model was used to build the static parts of these models. A FBHP limit of 40bars was assumed to take into account pump operating limits and to maintain the reservoir pressure above the bubble point. 300m, 600m and 900m lateral length wells were modelled, in conjunction with 4, 6 and 8 stages of fracs. Simulation results indicate that higher initial recoveries and peak oil rates are obtained with longer well lengths and also with more fracs and spacing. For a 25year forecast, the ultimate recovery ranging from 0.4% to 2.56% for 300m and 1000m laterals respectively. The 900m lateral with 8 fracs 100m spacing gave the highest peak rate of 120m3/day, with the 600m and 300m cases giving initial peak rates of 110m3/day. Similarly, recovery factor for the 900m lateral with 8 fracs and 100m spacing was the highest at 2.65% after 25 years. The corresponding values for the 300m and 600m laterals were 2.37% and 2.42%. Therefore, the study suggests that longer laterals with 8 fracs and 100m spacing provided the optimal recovery, and this design is recommended as the basis for further study.

Keywords: unconventional, resource, hydraulic, fracturing

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Authors: Yaser E. Hawas, Md. Didarul Alam

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Rollover crashes are complex events entailing interactions of driver, road, vehicle, and environmental factors. The primary objective of this paper is to present an empirical approach that can be used to characterise the rollover crashes and to identify some of the important factors that may lead to rollovers. Among the studied factors are the vehicle types and the rollover occurrence rate after hitting various barrier types. The carried analysis indicated that 71% of the rollover crashes occurred after impact and the type of rollover initiation is “trip/turn over” (nearly 50%). It was also found that light trucks (LTVs) vehicles are more likely to rollover than the sedan vehicles. Barrier impacts are associated with increased incidence of rollover.

Keywords: empirical, hitting barrier, in-depth crash investigation, rollover, severe crash

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Authors: M. Grifoni, G. Petruzzelli, M. Barbafieri, I. Rosellini, B. Pezzarossa, F. Pedron

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Evapotranspiration (ET) covers are an alternative cover system that utilizes water balance approach to maximize the ET process to reduce the contaminants leaching through the soil profile. Microcosm tests allow to identify in a short time the most suitable plant species to be used as alternative covers, their survival capacity, and simultaneously the transpiration and evaporation rate of the cover in a specific contaminated soil. This work shows the soil characterization and ET results of microcosm tests carried out on two contaminated soils by using Triticum durum and Helianthus annuus species. The data indicated that transpiration was higher than evaporation, supporting the use of plants as alternative cover at this contaminated site.

Keywords: contaminated sites, evapotranspiration cover, evapotranspiration, microcosm experiments

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Authors: Ramona Zharfpeykan

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This study analyses the trend and nature of sustainability key performance indicators (KPIs) reporting in firms globally. It presents both trend and panel data of sustainability reports of 798 firms in the Global Reporting Initiative (GRI) database from 2010 to 2014. The results show some fluctuations in the frequency of sustainability KPI reporting globally across the time while the major focus of reports in firms stayed almost the same. It made us further analyse this trend and found that there are some indicators, such as 'environmental protect expenses' and 'number of grievances', that was barely reported over this period along with some highly popular ones such as 'direct economic value' and 'employment rate'. We could not find any statistical correlation between the KPI reporting percentage and the firms’ industries generally and neither if they belong to environmentally sensitive industries.

Keywords: global reporting initiatives, sustainability reporting, sustainability KPI, trends of sustainability reporting

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Authors: Ashish Pathak, Dong-Jin Kim, Byoung-Gon Kim

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Biological processes based on oxidation of sulfur compounds by chemolithotrophic microorganisms are emerging as an efficient and eco-friendly technique for removal of sulfur from the coal. In the present article, study was carried out to investigate the potential of biodesulfurization process in removing the sulfur from lignite coal sample collected from a Mongolian coal mine. The batch biodesulfurization experiments were conducted in 2.5 L borosilicate baffle type reactors at 35 ºC using Acidithiobacillus ferrooxidans. The effect of pulp density on efficiency of biodesulfurization was investigated at different solids concentration (1-10%) of coal. The results of the present study suggested that the rate of desulfurization was retarded at higher coal pulp density. The optimum pulp density found 5% at which about 48% of the total sulfur was removed from the coal.

Keywords: biodesulfurization, bioreactor, coal, pyrite

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Authors: Vithya Veeramani, Karunanidhi Subbaiah

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Emotional problems were found to be the predominant cause of suicide and second leading cause of death among adolescents in India. Emotional problems seem to be the underlying cause for various other severe psycho-social problems experienced in adolescence and also in later years of life. The Corporation schools in Chennai city are named as Chennai High School or Chennai Higher Secondary School run by the Corporation of Chennai. These schools fulfill the educational needs of students who hail from lower socio-economic status living in slums of the Chennai city. Adolescent students of Chennai schools tend to lack basic needs like food, clothes, shelter, etc. Some of the other significant problems faced by them are broken family, lack of parental support, frequent quarrel between parents, alcoholic parents, drug abuse and substance abuse among parents and neighbors, extended family, illiterate parents, deprivation of love and care, and lack of sense of belongingness. This prevailing condition may affect them emotionally and could lead to maladaptive behaviour, aggressiveness, poor interpersonal relationship with others, school refusal behaviour, school drop-out, suicide, etc. Therefore, it is very important to investigate the emotional problems faced by the adolescent students studying in Chennai schools, Chennai. A cross-sectional survey design was used to find the prevalence of emotional problems among adolescent students. Cluster sampling technique was used to select the schools for the present study considering the school as a cluster. In total, there are 15 zones, under the control of Chennai Corporation, of which only 7 zones have Corporation Schools in Chennai city, comprising of 32 Chennai Higher Secondary Schools and 38 Chennai High Schools. Out of these 70 schools, 29 schools comprising of 17 high schools and 12 higher secondary schools were selected randomly using lottery method. A sample of 2594 adolescent students from 9th standard and 11th standard was chosen for the study. Percentage analysis was done to find out the prevalence rate of emotional problems among adolescents students studying in Chennai Schools. Results of the study revealed that, out of 2594 students surveyed, 21.04% adolescent students were found to have academic problems (n = 546), 15.99% adolescent students had social problems (n = 415), behaviour problems was found to be prevalent among 12.87% adolescent students (n = 334), depression was prevalent among 15.88% adolescent students (n = 412) and anxiety was prevalent among 14.42% adolescent students (n = 374). Prevalence of emotional problems among male and female revealed that academic problems were more prevalent compared to other problems. Behaviour problems were least prevalent among boys and anxiety was least prevalent among girls than other problems. The overall prevalence rate of emotional problems was found to be on an increasing trend among adolescent students of low socio-economic status in Chennai city. The findings indicated the need for intervention to prevent and rehabilitate these adolescent students.

Keywords: adolescents, corporation schools, emotional problems, prevalence

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Authors: Soheila Sadeghi

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In the dynamic landscape of project management, scope changes are an inevitable reality that can significantly impact project performance. These changes, whether initiated by stakeholders, external factors, or internal project dynamics, can lead to cost overruns and schedule delays. Accurately predicting the consequences of these changes is crucial for effective project control and informed decision-making. This study aims to develop predictive models to estimate the impact of scope changes on project cost and schedule using machine learning techniques. The research utilizes a comprehensive dataset containing detailed information on project tasks, including the Work Breakdown Structure (WBS), task type, productivity rate, estimated cost, actual cost, duration, task dependencies, scope change magnitude, and scope change timing. Multiple machine learning models are developed and evaluated to predict the impact of scope changes on project cost and schedule. These models include Linear Regression, Decision Tree, Ridge Regression, Random Forest, Gradient Boosting, and XGBoost. The dataset is split into training and testing sets, and the models are trained using the preprocessed data. Cross-validation techniques are employed to assess the robustness and generalization ability of the models. The performance of the models is evaluated using metrics such as Mean Squared Error (MSE) and R-squared. Residual plots are generated to assess the goodness of fit and identify any patterns or outliers. Hyperparameter tuning is performed to optimize the XGBoost model and improve its predictive accuracy. The feature importance analysis reveals the relative significance of different project attributes in predicting the impact on cost and schedule. Key factors such as productivity rate, scope change magnitude, task dependencies, estimated cost, actual cost, duration, and specific WBS elements are identified as influential predictors. The study highlights the importance of considering both cost and schedule implications when managing scope changes. The developed predictive models provide project managers with a data-driven tool to proactively assess the potential impact of scope changes on project cost and schedule. By leveraging these insights, project managers can make informed decisions, optimize resource allocation, and develop effective mitigation strategies. The findings of this research contribute to improved project planning, risk management, and overall project success.

Keywords: cost impact, machine learning, predictive modeling, schedule impact, scope changes

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Authors: Mohamed Rabhi, Kouider Halim Benrahou

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The rheological properties of the carbonyl-methylcellulose (CMC), of different concentrations (25000, 50000, 60000, 80000 and 100000 ppm) and different temperatures were studied. We found that the rheological behavior of all CMC solutions presents a pseudo-plastic behavior, it follows the model of Ostwald-de Waele. The objective of this work is the modeling of flow by the CMC Cross model. The Cross model gives us the variation of the viscosity according to the shear rate. This model allowed us to adjust more clearly the rheological characteristics of CMC solutions. A comparison between the Cross model and the model of Ostwald was made. Cross the model fitting parameters were determined by a numerical simulation to make an approach between the experimental curve and those given by the two models. Our study has shown that the model of Cross, describes well the flow of "CMC" for low concentrations.

Keywords: CMC, rheological modeling, Ostwald model, cross model, viscosity

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Authors: Swapnil Vidhate, Anupama Sharma

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At present the world is experiencing an extraordinary rate of urbanization. India is also in a major phase of urbanization. Gentrification is being practiced in India much later compared to western countries as a strategy for urban renewal. The urban fabric in Indian context is composed of multiple layers in it. Thus, the process of gentrification has different typologies, views and impacts in Indian context. It is a curative concept to restructure the declined areas of the city. But it has more negative views compared to positive due to the concerns in the process in India. The paper brings out the impacts of gentrification and concerns related with the process in Indian context with a case example of core city.

Keywords: urbanization, urban renewal, gentrification, restructure, core city

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Authors: N. Targui, H. Kahalerras

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The present work is a numerical simulation of nanofluids flow in a double pipe heat exchanger provided with porous baffles. The hot nanofluid flows in the inner cylinder, whereas the cold nanofluid circulates in the annular gap. The Darcy-Brinkman-Forchheimer model is adopted to describe the flow in the porous regions, and the governing equations with the appropriate boundary conditions are solved by the finite volume method. The results reveal that the addition of metallic nanoparticles enhances the rate of heat transfer in comparison to conventional fluids but this augmentation is accompanied by an increase in pressure drop. The highest heat exchanger performances are obtained when nanoparticles are added only to the cold fluid.

Keywords: double pipe heat exchanger, nanofluids, nanoparticles, porous baffles

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Authors: A. El Amri, M. El Yakhloufi Haddou, A. Khamlichi

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The numerical simulation based on the Finite Element Method (FEM) is widely used in academic institutes and in the industry. It is a useful tool to predict many phenomena present in the classical manufacturing forming processes such as fracture. But, the results of such numerical model depend strongly on the parameters of the constitutive behavior model. The influences of thermal and mechanical loads cause damage. The temperature and strain rate dependent materials’ properties and their modelling are discussed. A Johnson-Cook Model of damage has been selected for the numerical simulations. Virtual software called the ABAQUS 6.11 is used for finite element analysis. This model was introduced in order to give information concerning crack initiation during thermal and mechanical loads.

Keywords: thermo-mechanical fatigue, failure, numerical simulation, fracture, damage

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Authors: Brahim Mahfoud, Ali Bendjaghlouli

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Natural convection is simulated in a truncated cone filled with nanofluid. Inclined and top walls have constant temperature where the heat source is located on the bottom wall of the conical container which is thermally insulated. A finite volume approach is used to solve the governing equations using the SIMPLE algorithm for different parameters such as Rayleigh number, inclination angle of inclined walls of the enclosure and heat source length. The results showed an enhancement in cooling system by using a nanofluid, when conduction regime is assisted. The inclination angle of inclined sidewall and heat source length affect the heat transfer rate and the maximum temperature.

Keywords: heat source, truncated cone, nanofluid, natural convection

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Authors: Marcelo R. G. Duarte, Marcilio Alves

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Pedestrians are the fourth group among road traffic users that most suffer accidents. Their death rate is even higher than the motorcyclists group. This gives motivation for the development of an urban vehicle capable of complying with the United Nations Economic Commission for Europe pedestrian regulations. The conceptual vehicle is capable of transporting two passengers and small parcels for 100 km at a maximum speed of 90 km/h. This paper presents the design of this vehicle using the finite element method specially in connection with frontal crash test and car to pedestrian collision. The simulation is based in a human body FE.

Keywords: electric urban vehicle, finite element method, global human body model, pedestrian safety, road safety

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Authors: Shizra Waris, Saleem Akhtar

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Big data is a research area receiving attention from academia and IT communities. In the digital world, the amounts of data produced and stored have within a short period of time. Consequently this fast increasing rate of data has created many challenges. In this paper, we use functionalism and structuralism paradigms to analyze the genesis of big data applications and its current trends. This paper presents a complete discussion on state-of-the-art big data technologies based on group and stream data processing. Moreover, strengths and weaknesses of these technologies are analyzed. This study also covers big data analytics techniques, processing methods, some reported case studies from different vendor, several open research challenges and the chances brought about by big data. The similarities and differences of these techniques and technologies based on important limitations are also investigated. Emerging technologies are suggested as a solution for big data problems.

Keywords: computer, it community, industry, big data

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Authors: Oluwaponmile David Alao

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Misdiagnosis has been the major problem in health sector. Heart attack has been one of diseases that have high level of misdiagnosis recorded on the part of physicians. In this paper, an intelligent system has been developed for diagnosis of heart attack in the health sector. Dataset of heart attack obtained from UCI repository has been used. This dataset is made up of thirteen attributes which are very vital in diagnosis of heart disease. The system is developed on the multilayer perceptron trained with back propagation neural network then simulated with feed forward neural network and a recognition rate of 87% was obtained which is a good result for diagnosis of heart attack in medical field.

Keywords: heart attack, artificial neural network, diagnosis, intelligent system

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Authors: Vivek Kumar Singh, Tripti Singh

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An ad hoc wireless network consists of mobile networks which creates an underlying architecture for communication without the help of traditional fixed-position routers. Ad-hoc On-demand Distance Vector (AODV) is a routing protocol used for Mobile Ad hoc Network (MANET). Nevertheless, the architecture must maintain communication routes although the hosts are mobile and they have limited transmission range. There are different protocols for handling the routing in the mobile environment. Routing protocols used in fixed infrastructure networks cannot be efficiently used for mobile ad-hoc networks, so that MANET requires different protocols. This paper presents the performance analysis of the routing protocols used various parameter-patterns with Two-ray model.

Keywords: AODV, packet transmission rate, pause time, ZRP, QualNet 6.1

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Authors: Daniela Magalhaes, Jorge Pedro, Pedro Souteiro, Joao S. Neves, Sofia Castro-Oliveira, Vanessa Guerreiro, Rita Bettencourt- Silva, Maria M. Costa, Ana Varela, Joana Queiros, Paula Freitas, Davide Carvalho

Abstract:

Introduction: Obesity is an independent risk factor for renal dysfunction. Our aims were: (1) evaluate the impact of bariatric surgery (BS) on renal function; (2) clarify the factors determining the postoperative evolution of the glomerular filtration rate (GFR); (3) access the occurrence of oxalate-mediated renal complications. Methods: We investigated a cohort of 1448 obese patients who underwent bariatric surgery. Those with basal GFR (GFR0) < 30mL/min or without information about the GFR 2-year post-surgery (GFR2) were excluded. Results: We included 725 patients, of whom 647 (89.2%) women, with 41 (IQR 34-51) years, a median weight of 112.4 (IQR 103.0-125.0) kg and a median BMI of 43.4 (IQR 40.6-46.9) kg/m2. Of these, 459 (63.3%) performed gastric bypass (RYGB), 144 (19.9%) placed an adjustable gastric band (AGB) and 122 (16.8%) underwent vertical gastrectomy (VG). At 2-year post-surgery, excess weight loss (EWL) was 60.1 (IQR 43.7-72.4) %. There was a significant improve of metabolic and inflammatory status, as well as a significant decrease in the proportion of patients with diabetes, arterial hypertension and dyslipidemia (p < 0.0001). At baseline, 38 (5.2%) of subjects had hyperfiltration with a GFR0 ≥ 125mL/min/1.73m2, 492 (67.9%) had a GFR0 90-124 mL/min/1.73m2, 178 (24.6%) had a GFR0 60-89 mL/min/1.73m2, and 17 (2.3%) had a GFR0 < 60 mL/min/1.73m2. GFR decreased in 63.2% of patients with hyperfiltration (ΔGFR=-2.5±7.6), and increased in 96.6% (ΔGFR=22.2±12.0) and 82.4% (ΔGFR=24.3±30.0) of the subjects with GFR0 60-89 and < 60 mL/min/1.73m2, respectively ( p < 0.0001). This trend was maintained when adjustment was made for the type of surgery performed. Of 321 patients, 10 (3.3%) had a urinary albumin excretion (UAE) > 300 mg/dL (A3), 44 (14.6%) had a UAE 30-300 mg/dL (A2) and 247 (82.1%) has a UAE < 30 mg/dL (A1). Albuminuria decreased after surgery and at 2-year follow-up only 1 (0.3%) patient had A3, 17 (5.6%) had A2 and 283 (94%) had A1 (p < 0,0001). In multivariate analysis, the variables independently associated with ΔGFR were BMI (positively) and fasting plasma glucose (negatively). During the 2-year follow-up, only 57 of the 725 patients had transient urinary excretion of calcium oxalate crystals. None has records of oxalate-mediated renal complications at our center. Conclusions: The evolution of GFR after BS seems to depend on the initial renal function, as it decreases in subjects with hyperfiltration, but tends to increase in those with renal dysfunction. Our results suggest that BS is associated with improvement of renal outcomes, without significant increase of renal complications. So, apart the clear benefits in metabolic and inflammatory status, maybe obese adults with nondialysis-dependent CKD should be referred for bariatric surgery evaluation.

Keywords: albuminuria, bariatric surgery, glomerular filtration rate, renal function

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Authors: O. Bourkoukou, Essaid El Bachari

Abstract:

The group composing is one of the key issue in collaborative learning to achieve a positive educational experience. The goal of this work is to propose for teachers and tutors a method to create effective collaborative learning groups in e-learning environment based on the learner profile. For this purpose, a new function was defined to rate implicitly learning objects used by the learner during his learning experience. This paper describes the proposed algorithm to build an adequate collaborative learning group. In order to verify the performance of the proposed algorithm, several experiments were conducted in real data set in virtual environment. Results show the effectiveness of the method for which it appears that the proposed approach may be promising to produce better outcomes.

Keywords: building groups, collaborative learning, e-learning, learning objects

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Authors: Sara Ignoto, Elena M. Scalisi, Carmen Sica, Martina Contino, Greta Ferruggia, Antonio Salvaggio, Santi C. Pavone, Gino Sorbello, Loreto Di Donato, Roberta Pecoraro, Maria V. Brundo

Abstract:

The new fifth generation technology (5G), which should favor high data-rate connections (1Gbps) and latency times lower than the current ones (<1ms), has the characteristic of working on different frequency bands of the radio wave spectrum (700 MHz, 3.6-3.8 GHz and 26.5-27.5 GHz), thus also exploiting higher frequencies than previous mobile radio generations (1G-4G). The higher frequency waves, however, have a lower capacity to propagate in free space and therefore, in order to guarantee the capillary coverage of the territory for high reliability applications, it will be necessary to install a large number of repeaters. Following the introduction of this new technology, there has been growing concern in recent years about the possible harmful effects on human health and several studies were published using several animal models. This study aimed to observe the possible short-term effects induced by 5G-millimeter waves on heartbeat of early life stages of Danio rerio using DanioScope software (Noldus). DanioScope is the complete toolbox for measurements on zebrafish embryos and larvae. The effect of substances can be measured on the developing zebrafish embryo by a range of parameters: earliest activity of the embryo’s tail, activity of the developing heart, speed of blood flowing through the vein, length and diameters of body parts. Activity measurements, cardiovascular data, blood flow data and morphometric parameters can be combined in one single tool. Obtained data are elaborate and provided by the software both numerical as well as graphical. The experiments were performed at 27 GHz by a no commercial high gain pyramidal horn antenna. According to OECD guidelines, exposure to 5G-millimeter waves was tested by fish embryo toxicity test within 96 hours post fertilization, Observations were recorded every 24h, until the end of the short-term test (96h). The results have showed an increase of heartbeat rate on exposed embryos at 48h hpf than control group, but this increase has not been shown at 72-96 h hpf. Nowadays, there is a scant of literature data about this topic, so these results could be useful to approach new studies and also to evaluate potential cardiotoxic effects of mobile radiofrequency.

Keywords: Danio rerio, DanioScope, cardiotoxicity, millimeter waves.

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Authors: Shigenori Togashi, Kei Takenaka

Abstract:

We developed new processes which can collect and detect rapidly airborne pathogens such as the avian flu virus for the pandemic prevention. The fluorescence antibody technique is known as one of high-sensitive detection methods for viruses, but this needs up to a few hours to bind sufficient fluorescence dyes to viruses for detection. In this paper, we developed a mist-labeling can detect substitution viruses in a short time to improve the binding rate of fluorescent dyes and substitution viruses by the micro reaction process. Moreover, we developed the rapid detection system with the above 'mist labeling'. The detection system set with a sampling bag collecting patient’s breath and a cartridge can detect automatically pathogens within 10 minutes.

Keywords: viruses, sampler, mist, detection, fluorescent dyes, microreaction

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Authors: S. Ebadzadsahraei, H. Kazemian

Abstract:

The main objective of this research was to measure particulate matter (PM₂.₅) and Volatile Organic Compound (VOCs) as two classes of air pollutants, at Prince George (PG) neighborhood in warm and cold seasons. To fulfill this objective, analytical protocols were developed for accurate sampling and measurement of the targeted air pollutants. PM₂.₅ samples were analyzed for their chemical composition (i.e., toxic trace elements) in order to assess their potential source of emission. The City of Prince George, widely known as the capital of northern British Columbia (BC), Canada, has been dealing with air pollution challenges for a long time. The city has several local industries including pulp mills, a refinery, and a couple of asphalt plants that are the primary contributors of industrial VOCs. In this research project, which is the first study of this kind in this region it measures physical and chemical properties of particulate air pollutants (PM₂.₅) at the city neighborhood. Furthermore, this study quantifies the percentage of VOCs at the city air samples. One of the outcomes of this project is updated data about PM₂.₅ and VOCs inventory in the selected neighborhoods. For examining PM₂.₅ chemical composition, an elemental analysis methodology was developed to measure major trace elements including but not limited to mercury and lead. The toxicity of inhaled particulates depends on both their physical and chemical properties; thus, an understanding of aerosol properties is essential for the evaluation of such hazards, and the treatment of such respiratory and other related diseases. Mixed cellulose ester (MCE) filters were selected for this research as a suitable filter for PM₂.₅ air sampling. Chemical analyses were conducted using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for elemental analysis. VOCs measurement of the air samples was performed using a Gas Chromatography-Flame Ionization Detector (GC-FID) and Gas Chromatography-Mass Spectrometry (GC-MS) allowing for quantitative measurement of VOC molecules in sub-ppb levels. In this study, sorbent tube (Anasorb CSC, Coconut Charcoal), 6 x 70-mm size, 2 sections, 50/100 mg sorbent, 20/40 mesh was used for VOCs air sampling followed by using solvent extraction and solid-phase micro extraction (SPME) techniques to prepare samples for measuring by a GC-MS/FID instrument. Air sampling for both PM₂.₅ and VOC were conducted in summer and winter seasons for comparison. Average concentrations of PM₂.₅ are very different between wildfire and daily samples. At wildfire time average of concentration is 83.0 μg/m³ and daily samples are 23.7 μg/m³. Also, higher concentrations of iron, nickel and manganese found at all samples and mercury element is found in some samples. It is able to stay too high doses negative effects.

Keywords: air pollutants, chemical analysis, particulate matter (PM₂.₅), volatile organic compound, VOCs

Procedia PDF Downloads 145