Search results for: statistical evaluation
3595 Relationship of Oxidative Stress to Elevated Homocysteine and DNA Damage in Coronary Artery Disease Patients
Authors: Shazia Anwer Bukhari, Madiha Javeed Ghani, Muhammad Ibrahim Rajoka
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Objective: Biochemical, environmental, physical and genetic factors have a strong effect on the development of coronary disease (CAD). Plasma homocysteine (Hcy) level and DNA damage play a pivotal role in its development and progression. The aim of this study was to investigate the predictive strength of an oxidative stress, clinical biomarkers and total antioxidant status (TAS) in CAD patients to find the correlation of homocysteine, TOS and oxidative DNA damage with other clinical parameters. Methods: Sixty confirmed patients with CAD and 60 healthy individuals as control were included in this study. Different clinical and laboratory parameters were studied in blood samples obtained from patients and control subjects using commercially available biochemical kits and statistical software Results: As compared to healthy individuals, CAD patients had significantly higher concentrations of indices of oxidative stress: homocysteine (P=0.0001), total oxidative stress (TOS) (P=0.0001), serum cholesterol (P=0.04), low density lipoprotein cholesterol (LDL) (P=0.01), high density lipoprotein-cholesterol (HDL) (P=0.0001), and malondialdehyde (MDA) (P=0.001) than those of healthy individuals. Plasma homocysteine level and oxidative DNA damage were positively correlated with cholesterol, triglycerides, systolic blood pressure, urea, total protein and albumin (P values= 0.05). Both Hcy and oxidative DNA damage were negatively correlated with TAS and proteins. Conclusion: Coronary artery disease patients had a significant increase in homocysteine level and DNA damage due to increased oxidative stress. In conclusion, our study shows a significantly increase in lipid peroxidation, TOS, homocysteine and DNA damage in the erythrocytes of patients with CAD. A significant decrease level of HDL-C and TAS was observed only in CAD patients. Therefore these biomarkers may be useful diagnosis of patients with CAD and play an important role in the pathogenesis of CAD.Keywords: antioxidants, coronary artery disease, DNA damage, homocysteine, oxidative stress, malondialdehyde, 8-Hydroxy-2’deoxyguanosine
Procedia PDF Downloads 4863594 Development of a Passive Solar Tomato Dryer with Movable Heat Storage System
Authors: Jacob T. Liberty, Wilfred I. Okonkwo
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The present study designed and constructed a post-harvest passive solar tomato dryer of dimension 176 x 152 x 54cm for drying tomato. Quality of the dried crop was evaluated and compared with the fresh ones. The solar dryer consist of solar collector (air heater), 110 x 61 x 10 x 10cm, the drying chamber, 102 x54cm, removal heat storage unit, 40 x 35 x 13cm and drying trays, 43 x 42cm. The physicochemical properties of this crop were evaluated before and after drying. Physicochemical properties evaluated includes moisture, protein, fat, fibre, ash, carbohydrate and vitamin C, contents. The fresh, open and solar dried samples were analysed for their proximate composition using the recommended method of AOAC. Also, statistical analysis of the data was conducted using analysis of variance (ANOVA) using completely Randomize Design (CRD) and means were separated by Duncan’s New Multiple Range test (DNMRT). Proximate analysis showed that solar dried tomato had significantly (P < 0.05) higher protein, fibre, ash, carbohydrate and vitamin C except for the fat content that was significantly (P < 0.05) higher for all the open sun dried samples than the solar dried and fresh product. The nutrient which is highly affected by sun drying is vitamin C. Result indicates that moisture loss in solar dried tomato was faster and lower than the open dried samples and as such makes the solar dried products of lesser tendency to mould and bacterial growth. Also, the open sun dried samples had to be carried into the sheltered place each time it rained. The solar dried produce is of high quality. Further processing of the dried crops will involve packaging for commercial purposes. This will also help in making these agricultural product available in a relatively cheap price in off season and also avert micronutrient deficiencies in diet especially among the low-income groups in Nigeria.Keywords: tomato, passive solar dryer, physicochemical properties, removal heat storage
Procedia PDF Downloads 3113593 Normal Weight Obesity among Female Students: BMI as a Non-Sufficient Tool for Obesity Assessment
Authors: Krzysztof Plesiewicz, Izabela Plesiewicz, Krzysztof Chiżyński, Marzenna Zielińska
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Background: Obesity is an independent risk factor for cardiovascular diseases. There are several anthropometric parameters proposed to estimate the level of obesity, but until now there is no agreement which one is the best predictor of cardiometabolic risk. Scientists defined metabolically obese normal weight, who suffer from metabolic abnormalities, the same as obese individuals, and defined this syndrome as normal weight obesity (NWO). Aim of the study: The aim of our study was to determine the occurrence of overweight and obesity in a cohort of young, adult women, using standard and complementary methods of obesity assessment and to indicate those, who are at risk of obesity. The second aim of our study was to test additional methods of obesity assessment and proof that body mass index using alone is not sufficient parameter of obesity assessment. Materials and methods: 384 young women, aged 18-32, were enrolled into the study. Standard anthropometric parameters (waist to hips ratio (WTH), waist to height ratio (WTHR)) and two other methods of body fat percentage measurement (BFPM) were used in the study: electrical bioimpendance analysis (BIA) and skinfold measurement test by digital fat body mass clipper (SFM). Results: In the study group 5% and 7% of participants had waist to hips ratio and accordingly waist to height ratio values connected with visceral obesity. According to BMI 14% participants were overweight and obese. Using additional methods of body fat assessment, there were 54% and 43% of obese for BIA and SMF method. In the group of participants with normal BMI and underweight (not overweight, n =340) there were individuals with the level of BFPM above the upper limit, for the BIA 49% (n =164) and for the SFM 36 % (n=125). Statistical analysis revealed strong correlation between BIA and SFM methods. Conclusion: BMI using alone is not a sufficient parameter of obesity assessment. High percentage of young women with normal BMI values seem to be normal weight obese.Keywords: electrical bioimpedance, normal weight obesity, skin-fold measurement test, women
Procedia PDF Downloads 2793592 Performance Evaluation of Adsorption Refrigerating Systems
Authors: Nadia Allouache, Omar Rahli
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Many promising technologies have been developed to harness the sun's energy. These technologies help in economizing energy and environmental protection. The solar refrigerating systems are one of these important technologies. In addition to environmental benefits and energy saving, adsorption refrigerating systems have many advantages such as lack of moving parts, simplicity of construction and low operating costs. The work aimed to establish the main factors that affect the performances of an adsorption refrigerating system using different geometries of adsorbers and different adsorbent-adsorbate pairs. The numerical modeling of the heat and mass transfer in the system, using various working pairs, such as: activated carbon-ammonia, calcium chlorid-ammonia, activated carbon fiber- methanol and activated carbon AC35-methanol, show that the adsorber design can influence the system performances; The thermal performances of system are better in the annular configuration case. An optimal value of generating temperature is observed in annular adsorber case for which the thermal performance of the cooling system is maximal. While in the plate adsorber, above a certain value of generating temperature, the performance of the system remains almost constant. The environmental conditions such as solar radiation and pressure have a great influence in the system efficiency, and the choice of the working pair depends on the environmental conditions and the geometry of the adsorber.Keywords: adsorber geometry, numerical modeling, optimal environmental conditions, working pairs.
Procedia PDF Downloads 833591 Long-Term Efficacy of Integrated Constructed Wetlands for Pollutant Removal Using Biowaste Materials
Authors: Khadija Kraiem, Salma Bessadok, Dorra Tabassi, Atef Jaouani
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This study investigated the long-term impact of incorporating biowaste (i.e., cork and date stones) as a natural and cost-effective alternative to traditional substrates (e.g., gravel) in constructed wetlands (CWs). Results showed that pollutant removal efficiency was significantly improved after the addition of biowaste under different hydraulic retention time (HRT) conditions. The addition of cork in vertical flow constructed wetlands (VFCWs) improved chemical oxygen demand (COD) removal from 64% to 86%.. Similarly, in horizontal flow constructed wetlands (HFCWs), COD removal increased from 67% to 81% with cork and 85% with date seeds. In terms of ammonium removal, cork in VFCWs increased efficiency from 34% to 56%, while in HFCWs; it improved from 24% to 47% with cork and reached 44% with date stones. Furthermore, our data showed that the addition of biowastes improved the removal of micropollutants, such as bisphenol A (BPA) and diclofenac (DFC), with the highest removal of BPA of 86% and DFC of 89% observed in the date seeds wetland. However, no significant changes were observed in pathogens removal.The evaluation of the impact of biowaste addition on the contribution of plant species and its interaction with hydraulic retention time (HRT) was also conducted to pollutant removal. The addition of biowaste resulted in a decrease in the required HRT for effective contaminant elimination, but it had no notable impact on the contribution of plant species.Keywords: biowaste, constructed wetlands, micropollutants, wastewater tratment
Procedia PDF Downloads 83590 Optimization of Manufacturing Process Parameters: An Empirical Study from Taiwan's Tech Companies
Authors: Chao-Ton Su, Li-Fei Chen
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The parameter design is crucial to improving the uniformity of a product or process. In the product design stage, parameter design aims to determine the optimal settings for the parameters of each element in the system, thereby minimizing the functional deviations of the product. In the process design stage, parameter design aims to determine the operating settings of the manufacturing processes so that non-uniformity in manufacturing processes can be minimized. The parameter design, trying to minimize the influence of noise on the manufacturing system, plays an important role in the high-tech companies. Taiwan has many well-known high-tech companies, which show key roles in the global economy. Quality remains the most important factor that enables these companies to sustain their competitive advantage. In Taiwan however, many high-tech companies face various quality problems. A common challenge is related to root causes and defect patterns. In the R&D stage, root causes are often unknown, and defect patterns are difficult to classify. Additionally, data collection is not easy. Even when high-volume data can be collected, data interpretation is difficult. To overcome these challenges, high-tech companies in Taiwan use more advanced quality improvement tools. In addition to traditional statistical methods and quality tools, the new trend is the application of powerful tools, such as neural network, fuzzy theory, data mining, industrial engineering, operations research, and innovation skills. In this study, several examples of optimizing the parameter settings for the manufacturing process in Taiwan’s tech companies will be presented to illustrate proposed approach’s effectiveness. Finally, a discussion of using traditional experimental design versus the proposed approach for process optimization will be made.Keywords: quality engineering, parameter design, neural network, genetic algorithm, experimental design
Procedia PDF Downloads 1473589 Effects of Garlic and Stevia Extract Following Aerobic Exercise on Hypothalamic Semaphorin 4A and Plexin D1 Genes Expression in High-Fat Diet-Induced Obese Rats
Authors: Sayyed-Javad Ziaolhagh, Mojtaba Hokmabadi
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Introduction: Childhood obesity is a serious medical condition that affects children and adolescents even in the central nervous system. Semaphorins also play a role in the inflammatory process of the nervous system. On the other hand, it has been stated that garlic and stevia extracts following aerobic exercise are effective on immune system inflammation in addition to aerobic activity. Materials and Methods: For 15 weeks, 50 3-week-old male Wistar rats were fed with conventional rodent chow for control and a high-fat diet to induce obesity. Obese rats then were randomly assigned into 7 groups (n=5) based on the Lee index: healthy control (C), obese (OBS), obese + garlic (OBS+GAR), obese + Stevia (OBS+STV), obese + aerobic exercise (OBS+EXE), obese + garlic + aerobic exercise (OBS+GAR+EXE), and obese + stevia + aerobic exercise (OBS+STV+EXE). Training groups completed a progressive aerobic running program (at 8-15 m/min, 5-20 min/day, 5 days/week), and Stevia and garlic extract group (250 mg/kg/day, 5 days/week) were given orally once a day. Real-time PCR was used to determine the levels of Semaphorin 4A, and Plexin D1 gene expressions in the hypothalamus. Fold change analysis with ANOVA was performed for statistical analysis, with a significance threshold of P<0.05. Results: Body weight increased significantly in OBS compared to C (p= 0.013), but was not significantly changed in all treatment rats. Moreover, Semaphorin 4A was significantly increased in obese compared to control group (p= 0.041) and after 8 weeks, stevia extract (p=0.006), aerobic exercise (p=0.012) and garlic extract + aerobic exercise (p=0.008) significantly decreased compared to obese rats. In addition, Plexin D1 genes were also found in the hypothalamus of both obese and control rats but were insignificantly up-regulated when compared with the obese group (p=0.950). Conclusion: High-fat diet caused neuroinflammation by elevation of sema4A in obese rats and stevia, stevia with aerobic and garlic with aerobic could reduce this inflammation in rats. Also, none of them could alter Plexin D1.Keywords: sema 4A, plexin D1, garlic, stevia
Procedia PDF Downloads 743588 An Integrated Architecture of E-Learning System to Digitize the Learning Method
Authors: M. Touhidul Islam Sarker, Mohammod Abul Kashem
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The purpose of this paper is to improve the e-learning system and digitize the learning method in the educational sector. The learner will login into e-learning platform and easily access the digital content, the content can be downloaded and take an assessment for evaluation. Learner can get access to these digital resources by using tablet, computer, and smart phone also. E-learning system can be defined as teaching and learning with the help of multimedia technologies and the internet by access to digital content. E-learning replacing the traditional education system through information and communication technology-based learning. This paper has designed and implemented integrated e-learning system architecture with University Management System. Moodle (Modular Object-Oriented Dynamic Learning Environment) is the best e-learning system, but the problem of Moodle has no school or university management system. In this research, we have not considered the school’s student because they are out of internet facilities. That’s why we considered the university students because they have the internet access and used technologies. The University Management System has different types of activities such as student registration, account management, teacher information, semester registration, staff information, etc. If we integrated these types of activity or module with Moodle, then we can overcome the problem of Moodle, and it will enhance the e-learning system architecture which makes effective use of technology. This architecture will give the learner to easily access the resources of e-learning platform anytime or anywhere which digitizes the learning method.Keywords: database, e-learning, LMS, Moodle
Procedia PDF Downloads 1913587 Burnout Recognition for Call Center Agents by Using Skin Color Detection with Hand Poses
Authors: El Sayed A. Sharara, A. Tsuji, K. Terada
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Call centers have been expanding and they have influence on activation in various markets increasingly. A call center’s work is known as one of the most demanding and stressful jobs. In this paper, we propose the fatigue detection system in order to detect burnout of call center agents in the case of a neck pain and upper back pain. Our proposed system is based on the computer vision technique combined skin color detection with the Viola-Jones object detector. To recognize the gesture of hand poses caused by stress sign, the YCbCr color space is used to detect the skin color region including face and hand poses around the area related to neck ache and upper back pain. A cascade of clarifiers by Viola-Jones is used for face recognition to extract from the skin color region. The detection of hand poses is given by the evaluation of neck pain and upper back pain by using skin color detection and face recognition method. The system performance is evaluated using two groups of dataset created in the laboratory to simulate call center environment. Our call center agent burnout detection system has been implemented by using a web camera and has been processed by MATLAB. From the experimental results, our system achieved 96.3% for upper back pain detection and 94.2% for neck pain detection.Keywords: call center agents, fatigue, skin color detection, face recognition
Procedia PDF Downloads 2993586 Investigating the Relationship Between Alexithymia and Mobile Phone Addiction Along with the Mediating Role of Anxiety, Stress and Depression: A Path Analysis Study and Structural Model Testing
Authors: Pouriya Darabiyan, Hadis Nazari, Kourosh Zarea, Saeed Ghanbari, Zeinab Raiesifar, Morteza Khafaie, Hanna Tuvesson
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Introduction Since the beginning of mobile phone addiction, alexithymia, depression, anxiety and stress have been stated as risk factors for Internet addiction, so this study was conducted with the aim of investigating the relationship between Alexithymia and Mobile phone addiction along with the mediating role of anxiety, stress and depression. Materials and methods In this descriptive-analytical and cross-sectional study in 2022, 412 students School of Nursing & Midwifery of Ahvaz Jundishapur University of Medical Sciences were included in the study using available sampling method. Data collection tools were: Demographic Information Questionnaire, Toronto Alexithymia Scale (TAS-20), Depression, Anxiety, Stress Scale (DASS-21) and Mobile Phone Addiction Index (MPAI). Frequency, Pearson correlation coefficient test and linear regression were used to describe and analyze the data. Also, structural equation models and path analysis method were used to investigate the direct and indirect effects as well as the total effect of each dimension of Alexithymia on Mobile phone addiction with the mediating role of stress, depression and anxiety. Statistical analysis was done by SPSS version 22 and Amos version 16 software. Results Alexithymia was a predictive factor for mobile phone addiction. Also, Alexithymia had a positive and significant effect on depression, anxiety and stress. Depression, anxiety and stress had a positive and significant effect on mobile phone addiction. Depression, anxiety and stress variables played the role of a relative mediating variable between Alexithymia and mobile phone addiction. Alexithymia through depression, anxiety and stress also has an indirect effect on Internet addiction. Conclusion Alexithymia is a predictive factor for mobile phone addiction; And the variables of depression, anxiety and stress play the role of a relative mediating variable between Alexithymia and mobile phone addiction.Keywords: alexithymia, mobile phone, depression, anxiety, stress
Procedia PDF Downloads 1003585 Quantification of Global Cerebrovascular Reactivity in the Principal Feeding Arteries of the Human Brain
Authors: Ravinder Kaur
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Introduction Global cerebrovascular reactivity (CVR) mapping is a promising clinical assessment for stress-testing the brain using physiological challenges, such as CO₂, to elicit changes in perfusion. It enables real-time assessment of cerebrovascular integrity and health. Conventional imaging approaches solely use steady-state parameters, like cerebral blood flow (CBF), to evaluate the integrity of the resting parenchyma and can erroneously show a healthy brain at rest, despite the underlying pathogenesis in the presence of cerebrovascular disease. Conversely, coupling CO₂ inhalation with phase-contrast MRI neuroimaging interrogates the capacity of the vasculature to respond to changes under stress. It shows promise in providing prognostic value as a novel health marker to measure neurovascular function in disease and to detect early brain vasculature dysfunction. Objective This exploratory study was established to:(a) quantify the CBF response to CO₂ in hypocapnia and hypercapnia,(b) evaluate disparities in CVR between internal carotid (ICA) and vertebral artery (VA), and (c) assess sex-specific variation in CVR. Methodology Phase-contrast MRI was employed to measure the cerebrovascular reactivity to CO₂ (±10 mmHg). The respiratory interventions were presented using the prospectively end-tidal targeting RespirActTM Gen3 system. Post-processing and statistical analysis were conducted. Results In 9 young, healthy subjects, the CBF increased from hypocapnia to hypercapnia in all vessels (4.21±0.76 to 7.20±1.83 mL/sec in ICA, 1.36±0.55 to 2.33±1.31 mL/sec in VA, p < 0.05). The CVR was quantitatively higher in ICA than VA (slope of linear regression: 0.23 vs. 0.07 mL/sec/mmHg, p < 0.05). No statistically significant effect was observed in CVR between male and female (0.25 vs 0.20 mL/sec/mmHg in ICA, 0.09 vs 0.11 mL/sec/mmHg in VA, p > 0.05). Conclusions The principal finding in this investigation validated the modulation of CBF by CO₂. Moreover, it has indicated that regional heterogeneity in hemodynamic response exists in the brain. This study provides scope to standardize the quantification of CVR prior to its clinical translation.Keywords: cerebrovascular disease, neuroimaging, phase contrast MRI, cerebrovascular reactivity, carbon dioxide
Procedia PDF Downloads 1533584 Contextual Variables Affecting Frustration Level in Reading: An Integral Inquiry
Authors: Mae C. Pavilario
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This study employs a sequential explanatory mixed method. Quantitatively it investigated the profile of grade VII students. Qualitatively, the prevailing contextual variables that affect their frustration-level were sought based on their perspective and that of their parents and teachers. These students were categorized as frustration-level in reading based on the data on word list of the Philippine Informal Reading Inventory (Phil-IRI). The researcher-made reading factor instrument translated to local dialect (Hiligaynon) was subjected to cross-cultural translation to address content, semantic, technical, criterion, or conceptual equivalence, the open-ended questions, and one unstructured interview was utilized. In the profile of the 26 participants, the 12 males are categorized as grade II and grade III frustration-levels. The prevailing contextual variables are personal-“having no interest in reading”, “being ashamed and fear of having to read in front of others” for extremely high frustration level; social environmental-“having no regular reading schedule at home” for very high frustration level and personal- “having no interest in reading” for high frustration level. Kendall Tau inferential statistical tool was used to test the significant relationship in the prevailing contextual variables that affect frustration-level readers when grouped according to perspective. Result showed that significant relationship exists between students-parents perspectives; however, there is no significant relationship between students’ and teachers’, and parents’ and teachers’ perspectives. The themes in the narratives of the participants on frustration-level readers are existence of speech defects, undesirable attitude, insufficient amount of reading materials, lack of close supervision from parents, and losing time and focus on task. Intervention was designed.Keywords: contextual variables, frustration-level readers, perspective, inquiry
Procedia PDF Downloads 1663583 Dynamic Modelling of Hepatitis B Patient Using Sihar Model
Authors: Alakija Temitope Olufunmilayo, Akinyemi, Yagba Joy
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Hepatitis is the inflammation of the liver tissue that can cause whiteness of the eyes (Jaundice), lack of appetite, vomiting, tiredness, abdominal pain, diarrhea. Hepatitis is acute if it resolves within 6 months and chronic if it last longer than 6 months. Acute hepatitis can resolve on its own, lead to chronic hepatitis or rarely result in acute liver failure. Chronic hepatitis may lead to scarring of the liver (Cirrhosis), liver failure and liver cancer. Modelling Hepatitis B may become necessary in order to reduce its spread. So, dynamic SIR model can be used. This model consists of a system of three coupled non-linear ordinary differential equation which does not have an explicit formula solution. It is an epidemiological model used to predict the dynamics of infectious disease by categorizing the population into three possible compartments. In this study, a five-compartment dynamic model of Hepatitis B disease was proposed and developed by adding control measure of sensitizing the public called awareness. All the mathematical and statistical formulation of the model, especially the general equilibrium of the model, was derived, including the nonlinear least square estimators. The initial parameters of the model were derived using nonlinear least square embedded in R code. The result study shows that the proportion of Hepatitis B patient in the study population is 1.4 per 1,000,000 populations. The estimated Hepatitis B induced death rate is 0.0108, meaning that 1.08% of the infected individuals die of the disease. The reproduction number of Hepatitis B diseases in Nigeria is 6.0, meaning that one individual can infect more than 6.0 people. The effect of sensitizing the public on the basic reproduction number is significant as the reproduction number is reduced. The study therefore recommends that programme should be designed by government and non-governmental organization to sensitize the entire Nigeria population in order to reduce cases of Hepatitis B disease among the citizens.Keywords: hepatitis B, modelling, non-linear ordinary differential equation, sihar model, sensitization
Procedia PDF Downloads 963582 Evaluation of the Performance of ACTIFLO® Clarifier in the Treatment of Mining Wastewaters: Case Study of Costerfield Mining Operations, Victoria, Australia
Authors: Seyed Mohsen Samaei, Shirley Gato-Trinidad
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A pre-treatment stage prior to reverse osmosis (RO) is very important to ensure the long-term performance of the RO membranes in any wastewater treatment using RO. This study aims to evaluate the application of the Actiflo® clarifier as part of a pre-treatment unit in mining operations. It involves performing analytical testing on RO feed water before and after installation of Actiflo® unit. Water samples prior to RO plant stage were obtained on different dates from Costerfield mining operations in Victoria, Australia. Tests were conducted in an independent laboratory to determine the concentration of various compounds in RO feed water before and after installation of Actiflo® unit during the entire evaluated period from December 2015 to June 2018. Water quality analysis shows that the quality of RO feed water has remarkably improved since installation of Actiflo® clarifier. Suspended solids (SS) and turbidity removal efficiencies has been improved by 91 and 85 percent respectively in pre-treatment system since the installation of Actiflo®. The Actiflo® clarifier proved to be a valuable part of pre-treatment system prior to RO. It has the potential to conveniently condition the mining wastewater prior to RO unit, and reduce the risk of RO physical failure and irreversible fouling. Consequently, reliable and durable operation of RO unit with minimum requirement for RO membrane replacement is expected with Actiflo® in use.Keywords: ACTIFLO ® clarifier, mining wastewater, reverse osmosis, water treatment
Procedia PDF Downloads 1983581 Care and Support for Infants and Toddlers with Special Needs
Authors: Florence A. Undiyaundeye, Aniashie Akpanke
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Early identification of developmental disorders in infants and toddlers is critical for the well being of children. It is also an integral function of the primary care medical provider and the early care given in the home or crèche. This paper is focused at providing information on special need infants and toddlers and strategies to support them in developmental concern to cope with the challenges in and out of the classroom and to interact with their peers without stigmatization and inferiority complex. The target children are from birth through three years of age. There is a strong recommendation for developmental surveillance to be incorporated at every well child preventive care program in training and practical stage of formal school settings. The paper posits that any concerns raised during surveillance should be promptly addressed with standardized developmental screening by appropriate health service providers. In addition screening tests should be administered regularly at age 9+, 19+ and 30 months of these infants. The paper also establishes that the early identification of these developmental challenges of the infants and toddlers should lead to further developmental and medical evaluation, diagnosis and treatment, including early developmental school intervention, control and teaching and learning integration and inclusion for proper career build up. Children diagnosed with developmental disorders should be identified as children with special needs so that management is initiated and its underlying etiology may also drive a range of treatment of the child, to parents. Conselling and school integration as applicable to the child’s specific need and care for sustenance in societal functioning.Keywords: care, special need, support, infants and toddlers, management and developmental disorders
Procedia PDF Downloads 3893580 Effect of Noise Reduction Algorithms on Temporal Splitting of Speech Signal to Improve Speech Perception for Binaural Hearing Aids
Authors: Rajani S. Pujar, Pandurangarao N. Kulkarni
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Increased temporal masking affects the speech perception in persons with sensorineural hearing impairment especially under adverse listening conditions. This paper presents a cascaded scheme, which employs a noise reduction algorithm as well as temporal splitting of the speech signal. Earlier investigations have shown that by splitting the speech temporally and presenting alternate segments to the two ears help in reducing the effect of temporal masking. In this technique, the speech signal is processed by two fading functions, complementary to each other, and presented to left and right ears for binaural dichotic presentation. In the present study, half cosine signal is used as a fading function with crossover gain of 6 dB for the perceptual balance of loudness. Temporal splitting is combined with noise reduction algorithm to improve speech perception in the background noise. Two noise reduction schemes, namely spectral subtraction and Wiener filter are used. Listening tests were conducted on six normal-hearing subjects, with sensorineural loss simulated by adding broadband noise to the speech signal at different signal-to-noise ratios (∞, 3, 0, and -3 dB). Objective evaluation using PESQ was also carried out. The MOS score for VCV syllable /asha/ for SNR values of ∞, 3, 0, and -3 dB were 5, 4.46, 4.4 and 4.05 respectively, while the corresponding MOS scores for unprocessed speech were 5, 1.2, 0.9 and 0.65, indicating significant improvement in the perceived speech quality for the proposed scheme compared to the unprocessed speech.Keywords: MOS, PESQ, spectral subtraction, temporal splitting, wiener filter
Procedia PDF Downloads 3303579 Liquidity Risk of Banks in Light of a Dominant Share of Foreign Capital in the Polish Banking Sector
Authors: Karolina Patora
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This article investigates liquidity risk management by banks, which has gained significant importance since the global financial crisis of 2008. The issue is of particular interest for countries like Poland, in which foreign capital plays a dominant role. Such an ownership structure poses certain risks to the local banking sector, which faces an increased probability of the withdrawal of funding or assets’ transfers abroad in case of a crisis. Both these factors can have a detrimental influence on the liquidity position of foreign-owned banks and hence negatively affect the financial stability of the whole banking sector. The aim of this study is to evaluate the impact of a dominating share of foreign investors in the Polish banking sector on the liquidity position of commercial banks. The study hypothesizes that the ownership structure of the Polish banking sector, in which there are banks predominantly controlled by foreign investors, does not pose a threat to the liquidity position of Polish banks. A supplementary research hypothesis is that the liquidity risk profile of foreign-owned banks differs from that of domestic banks. The sample consists of 14 foreign-owned banks and 5 domestic banks owned by local investors, which together constitute approximately 87% of the banking sector’s assets. The data covers the period of 2004–2014. The results of the regression models show no evidence of significant differences in terms of the dynamics of changes of the liquidity buffers between the foreign-owned and domestic banks, although the signs of the coefficients might suggest that the foreign-owned banks were decreasing the holdings of liquid assets at a slower pace over the examined period, compared to the domestic banks. However, no proof of the statistical significance of these findings has been found. The supplementary research hypothesis that the liquidity risk profile of foreign-controlled banks differs from that of domestic banks was rejected.Keywords: foreign-owned banks, liquidity position, liquidity risk, financial stability
Procedia PDF Downloads 3003578 Molecular Detection of Helicobacter Pylori and Its Association with TNFα-308 Polymorphism in Cardiovascular Diseases
Authors: Azar Sharafianpor, Hossein Rassi, Fahimeh Nemati Mansur
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Cardiovascular diseases (CVD) are the most important cause of death in industrialized and developing countries such as Iran. The most important risk factors for the CVD, genetic factors and chronic infectious agents, such as Helicobacter pylori, can be mentioned. The TNFα gene is one of the most important anti-inflammatory cytokines that can affect the sensitivity, efficacy, and ability of the immune response to chronic infections. Some TNF-α gene polymorphisms, including the replacement of the G nucleotide G with A at position 308 in the promoter region of TNF-α, increase the transcription of cytokines in the target cells and thus predispose a person to chronic infections. This study examines the TNF-α 308 polymorphism and its association with Helicobacter pylori infection in this disease. This study was a case-control study in which 154 patients were examined as cases or patients with symptoms of myocardial infarction or angina and 160 as controls or healthy subjects. All of the subjects at different ages were given venous blood and age, BMI, cholesterol, LDL, and HDL were determined. DNA was extracted from the specimens, and the cagA gene from H. pylori and the TNF-α-308 polymorphism were determined by PCR in patients and healthy subjects. Statistical analysis was performed with Epi Info software. The results showed that the frequency of H. pylori infection in the patients and healthy group were 53.23% (82 out of 154) and 47.5% (76 out of 160). There was no significant difference in H. pylori outbreak between the two groups. The frequencies of TNF-α-308 genotype for GG, GA, and AA in patients were 0.17, 0.49, and 0.34, respectively, whereas for controls 0.47, 0.35, and 0.18 for GG, GA, and AA, respectively. The frequency of genotype analysis of TNF-α-308 polymorphisms in both patients and healthy groups showed that there was a significant difference in the frequency of genotypes and the AA genotype was higher in the affected individuals. Also, there was a significant relationship between the genotype and the contamination with H. pylori and changes in cholesterol, LDL, and HDL levels were observed. The results of the study indicate that H. pylori detection in individuals with AA genotype in people under 50 years of age can play an important role in early diagnosis and treatment of cardiovascular disease.Keywords: Helicobacter pylori, TNFα gene, cardiovascular diseases, TNFα-308 polymorphism
Procedia PDF Downloads 1573577 Determination of Lithology, Porosity and Water Saturation for Mishrif Carbonate Formation
Authors: F. S. Kadhim, A. Samsuri, H. Alwan
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Well logging records can help to answer many questions from a wide range of special interested information and basic petrophysical properties to formation evaluation of oil and gas reservoirs. The accurate calculations of porosity in carbonate reservoirs are the most challenging aspects of well log analysis. Many equations have been developed over the years based on known physical principles or on empirically derived relationships, which are used to calculate porosity, estimate lithology and water saturation; however these parameters are calculated from well logs by using modern technique in a current study. Nasiriya (NS) oilfield is one of giant oilfields in the Middle East, and the formation under study is the Mishrif carbonate formation which is the shallowest hydrocarbon bearing zone in the NS oilfield. Neurolog software (V5, 2008) was used to digitize the scanned copies of the available logs. Environmental corrections had been made as per Schlumberger charts 2005, which supplied in the Interactive Petrophysics software (IP, V3.5, 2008). Three saturation models have been used to calculate water saturation of carbonate formations, which are simple Archie equation, Dual water model, and Indonesia model. Results indicate that the Mishrif formation consists mainly of limestone, some dolomite and shale. The porosity interpretation shows that the logging tools have a good quality after making the environmental corrections. The average formation water saturation for Mishrif formation is around 0.4-0.6.This study is provided accurate behavior of petrophysical properties with depth for this formation by using modern software.Keywords: lithology, porosity, water saturation, carbonate formation, mishrif formation
Procedia PDF Downloads 3783576 Therapeutic Evaluation of Bacopa Monnieri Extract on Liver Fibrosis in Rats
Authors: Yu Wen Wang, Shyh Ming Kuo, Hsia Ying Cheng, Yu Chiuan Wu
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Liver fibrosis is caused by the activation of hepatic stellate cells in the liver to secrete excessive and deposition of extracellular matrix. In recent years, many treatment strategies have been developed to reduce the activation of hepatic stellate cells and therefore to increase the decomposition of extracellular matrix. Bacopa monnieri, an herbaceous plant of the scrophulariaceae, containing saponins and glycosides, which with antioxidant, anti-inflammation, pain relief and free radical scavenging characteristics. This study was to evaluate the inhibition of hepatic stellate cell activity by Bacopa monnieri extract and its therapeutic potential in treating thioacetamide-induced liver fibrosis in rats. The results showed that the IC50 of Bacopa monnieri extract was 0.39 mg/mL. Bacopa monnieri extract could effectively reduce H2O2-induced hepatic stellate cells inflammation. In the TAA-induced liver fibrosis animal studies, albumin secretion recovered to normal level after treated with Bacopa monnieri extract for 2-w, and fibrosis related proteins, α-SMA and TGF-1levels decreased indicating the extract exerted therapeutic effect on the liver fibrosis. However, inflammatory factors TNF- obviously decreased after 4-w treatment. In summary, we could successfully extract the main component-Bacopaside I from the plant and acquired a potential therapy using this component in treating TAA-induced liver fibrosis in rat.Keywords: anti-inflammatory, Bacopa monnieri, fibrosis, hepatic stellate cells, water extract
Procedia PDF Downloads 1133575 Relation of Cad/Cam Zirconia Dental Implant Abutments with Periodontal Health and Final Aesthetic Aspects; A Systematic Review
Authors: Amin Davoudi
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Aim: New approaches have been introduced to improve soft tissue indices of the dental implants. This systematic review aimed to investigate the effect of computer-aided design and computer-assisted manufacture (CAD/CAM) zirconia (Zr) implant abutments on periodontal aspects. Materials and Methods: Five electronic databases were searched thoroughly based on prior defined MeSH and non-MeSH keywords. Clinical studies were collected via hand searches in English language journals up to September 2020. Interproximal papilla stability, papilla recession, pink and white esthetic score (PES, WES), bone and gingival margin levels, color, and contour of soft tissue were reviewed. Results: The initial literature search yielded 412 articles. After the evaluation of abstracts and full texts, six studies were eligible to be screened. The study design of the included studies was a prospective cohort (n=3) and randomized clinical trial (n=3). The outcome was found to be significantly better for Zr than titanium abutments, however, the studies did not show significant differences between stock and CAD/CAM abutments. Conclusion: Papilla fill, WES, PES, and the distance from the contact point to dental crest bone of adjacent tooth and inter-tooth–implant distance were not significantly different between Zr CAD/CAM and Zr stock abutments. However, soft tissue stability and recession index were better in Zr CAD/CAM abutments.Keywords: zirconia, CADCAM, periodental, implant
Procedia PDF Downloads 1043574 Evaluation of Impact on Traffic Conditions Due to Electronic Toll Collection System Design in Thailand
Authors: Kankrong Suangka
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This research explored behaviors of toll way users that impact their decision to use the Electronic Toll Collection System (ETC). It also went on to explore and evaluated the efficiency of toll plaza in terms of number of ETC booths in toll plaza and its lane location. The two main parameters selected for the scenarios analyzed were (1) the varying ration of ETC enabled users (2) the varying locations of the dedicated ETC lane. There were a total of 42 scenarios analyzed. Researched data indicated that in A.D.2013, the percentage of ETC user from the total toll user is 22%. It was found that the delay at the payment booth was reduced by increasing the ETC booth by 1 more lane under the condition that the volume of ETC users passing through the plaza less than 1,200 vehicles/hour. Meanwhile, increasing the ETC lanes by 2 lanes can accommodate an increased traffic volume to around 1,200 to 1,800 vehicles/hour. Other than that, in terms of the location of ETC lane, it was found that if for one ETC lane-plazas, installing the ETC lane at the far right are the best alternative. For toll plazas with 2 ETC lanes, the best layout is to have 1 lane in the middle and 1 lane at the far right. This layout shows the least delay when compared to other layouts. Furthermore, the results from this research showed that micro-simulator traffic models have potential for further applications and use in designing toll plaza lanes. Other than that, the results can also be used to analyze the system of the nearby area with similar traffic volume and can be used for further design improvements.Keywords: the electronic toll collection system, average queuing delay, toll plaza configuration, bioinformatics, biomedicine
Procedia PDF Downloads 2423573 Evaluation of Zooplankton Community and Saprobi Index of Carps Culture Ponds: Case Study on East of Golestan Province-Gonbade Kavous City
Authors: Mehrdad Kamali-Sanzighi, Maziar Kamali-Sanzighi
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The aim of this research was to study zooplankton community density, diversity and Saprobi index in carp ponds at Golestan province, Gonbade Kavous city, Iran. Zooplankton sampling was done monthly in each pond during one carp culture time. Our analysis showed 27 genus from 4 groups (Protozoa 12, Rotatoria 8, Copepoda 4 and Cladocera 3). The highest and lowest frequency of zooplankton groups were belongs to Rotatoria, Copepoda, Cladocera and Protozoa with 46, 28, 23 and 3 percent, respectively. No significant differences between saprobi index of six carp ponds (P>0.05) were observed. Saprobi index indicated Class ßmesosaprob for six analysis ponds. There was a general tendency to decrease and significantly in the saprobi index with the value range of 1.52-1.70 from the beginning to end of the culture season (P<0.05). Also, gradual improvement of water quality observed toward the end of culture period and these reasons are partly a result of natural and management processed such as seasons changes (climate), water exchange (replacement of water) and pause of introduce of fertilizer materials to the ponds. According to the ability of saprobi index in monitoring of water quality condition and health of different water resources, focus to similar kind of effective research is necessary in future time.Keywords: zooplankton, saprobi pollution index, water quality, fish pond, east of Golestan Province
Procedia PDF Downloads 1043572 One-Class Classification Approach Using Fukunaga-Koontz Transform and Selective Multiple Kernel Learning
Authors: Abdullah Bal
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This paper presents a one-class classification (OCC) technique based on Fukunaga-Koontz Transform (FKT) for binary classification problems. The FKT is originally a powerful tool to feature selection and ordering for two-class problems. To utilize the standard FKT for data domain description problem (i.e., one-class classification), in this paper, a set of non-class samples which exist outside of positive class (target class) describing boundary formed with limited training data has been constructed synthetically. The tunnel-like decision boundary around upper and lower border of target class samples has been designed using statistical properties of feature vectors belonging to the training data. To capture higher order of statistics of data and increase discrimination ability, the proposed method, termed one-class FKT (OC-FKT), has been extended to its nonlinear version via kernel machines and referred as OC-KFKT for short. Multiple kernel learning (MKL) is a favorable family of machine learning such that tries to find an optimal combination of a set of sub-kernels to achieve a better result. However, the discriminative ability of some of the base kernels may be low and the OC-KFKT designed by this type of kernels leads to unsatisfactory classification performance. To address this problem, the quality of sub-kernels should be evaluated, and the weak kernels must be discarded before the final decision making process. MKL/OC-FKT and selective MKL/OC-FKT frameworks have been designed stimulated by ensemble learning (EL) to weight and then select the sub-classifiers using the discriminability and diversities measured by eigenvalue ratios. The eigenvalue ratios have been assessed based on their regions on the FKT subspaces. The comparative experiments, performed on various low and high dimensional data, against state-of-the-art algorithms confirm the effectiveness of our techniques, especially in case of small sample size (SSS) conditions.Keywords: ensemble methods, fukunaga-koontz transform, kernel-based methods, multiple kernel learning, one-class classification
Procedia PDF Downloads 283571 Passenger Preferences on Airline Check-In Methods: Traditional Counter Check-In Versus Common-Use Self-Service Kiosk
Authors: Cruz Queen Allysa Rose, Bautista Joymeeh Anne, Lantoria Kaye, Barretto Katya Louise
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The study presents the preferences of passengers on the quality of service provided by the two airline check-in methods currently present in airports-traditional counter check-in and common-use self-service kiosks. Since a study has shown that airlines perceive self-service kiosks alone are sufficient enough to ensure adequate services and customer satisfaction, and in contrast, agents and passengers stated that it alone is not enough and that human interaction is essential. In reference with former studies that established opposing ideas about the choice of the more favorable airline check-in method to employ, it is the purpose of this study to present a recommendation that shall somehow fill-in the gap between the conflicting ideas by means of comparing the perceived quality of service through the RATER model. Furthermore, this study discusses the major competencies present in each method which are supported by the theories–FIRO Theory of Needs upholding the importance of inclusion, control and affection, and the Queueing Theory which points out the discipline of passengers and the length of the queue line as important factors affecting quality service. The findings of the study were based on the data gathered by the researchers from selected Thomasian third year and fourth year college students currently enrolled in the first semester of the academic year 2014-2015, who have already experienced both airline check-in methods through the implication of a stratified probability sampling. The statistical treatments applied in order to interpret the data were mean, frequency, standard deviation, t-test, logistic regression and chi-square test. The final point of the study revealed that there is a greater effect in passenger preference concerning the satisfaction experienced in common-use self-service kiosks in comparison with the application of the traditional counter check-in.Keywords: traditional counter check-in, common-use self-service Kiosks, airline check-in methods
Procedia PDF Downloads 4103570 Evaluation of Nitrogen Fixation Capabilities of Selected Pea Lines Grown under Different Environmental Conditions in Canadian Prairie
Authors: Chao Yang, Rosalind Bueckert, Jeff Schoenau, Axel Diederichsen, Hossein Zakeri, Tom Warkentin
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Pea is a very popular pulse crop that widely grew in Western Canadian prairie. However, the N fixation capabilities of these pea lines were not well evaluated under local environmental conditions. In this study, 2 supernodulating mutants Frisson P64 Sym29, Frisson P88 Sym28 along with their wild parent Frisson, 1 hypernodulating mutant Rondo-nod3 (fix+) along with its wild parent Rondo, 1 non-nodulating mutant Frisson P56 (nod-) and 2 commercial pea cultivar CDC Meadow and CDC Dakota which are widely planted in Western Canada were selected in order to evaluate the capabilities of their BNF, biomass, and yield production in symbiosis with R. leguminosarumbv. viciae, Our results showed different environmental conditions and variation of pea lines could both significantly impact days to flowering (DTF), days to podding (DTP), biomass and yield of tested pea lines (P < 0.0001), suggesting consideration of environmental factors could be important when selecting pea cultivar for local farming under different soil zones in Western Canada. Significant interaction effects between environmental conditions and pea lines were found on pea N fixation as well (P = 0.001), suggesting changes in N fixation capability of the same pea cultivar when grown under different environmental conditions. Our results provide useful information for farming and better opportunity for selection of pea cultivars with higher N-fixing capacity during breeding programs in Western Canada.Keywords: Canadian prairie, environmental condition, N fixation, pea cultivar
Procedia PDF Downloads 3483569 Antibacterial Effects of Garcinia mangostana on Canine Superficial Pyoderma Pathogen, Staphylococcus pseudintermedius
Authors: Sineenat Kempubpha, Phornpa-Ngan Muadmuang, Putthamas Phetmuangprab, Surin Promphet, Sopita Bandit
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Introduction: Discarded pericarp of mangosteen (Garcinia mangostana) is a benefit to be developed as veterinary phytopharmacal products since it made up of abundance pharmacological active compounds. The active compounds of mangosteen pericarp not only act as an antihistamine, an anti-inflammatory, heart disease and HIV therapeutic substances but also act as antibacterial and antifungal agents. Aim: This study was an in vitro procedural attempt to determine the antibacterial effects of mangosteen pericarp 95% ethanol extract on the main causative pathogen of canine superficial pyoderma, Staphylococcus pseudintermedius. Methods: S. pseudintermedius were collected from various sites of the skin of canine superficial pyoderma dogs and were revived and lawn cultured. The S. pseudintermedius growth inhibition study was determined by disc diffusion technique, the mangosteen pericarp crude extracted was dissolved in 3 types of solvents (95% ethanol, 2% DMSO and distilled water, respectively). The micro broth dilution technique was used for determining both minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values. Statistical analysis was done by calculating the mean of the zones of inhibition of tested microorganisms. Results: S. pseudintermedius growth inhibition study showed that the inhibition efficacy of 95% ethanol was greater than the inhibition efficacy of 2% DMSO and distilled water (9.10±0.18 mm, 6.95±0.60 mm and 6.80±0.18 mm, respectively). The MIC value was 125 µg/ml and the MBC value was 1 mg/ml. Conclusion: Mangosteen pericarp extract dissolved with 95% ethanol showed the highest zone of inhibition against the tested microorganisms. The MIC value was 125 µg/ml and the MBC value was 1 mg/ml which suggests its potent antibacterial action against S. pseudintermedius. However, further analytical studies are needed to isolate the key molecules of mangosteen pericarp for higher effect on canine superficial pyoderma microorganism therapeutic products.Keywords: mangosteen, Garcinia mangostana, Staphylococcus pseudintermedius, canine superficial pyoderma, in vitro study
Procedia PDF Downloads 2823568 Influence of Geomagnetic Storms on Ionospheric Parameters
Authors: Affan Ahmed
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This research investigates the Influence of geomagnetic storm occurring from April 22 to April 26, 2023, on the Earth’s ionosphere, with a focus on analyzing specific ionospheric parameters to understand the storm's effects on ionospheric stability and GNSS signal propagation. Geomagnetic storms, caused by intensified solar wind-magnetosphere interactions, can significantly disturb ionospheric conditions, impacting electron density, Total Electron Content (TEC), and thermospheric composition. Such disturbances are particularly relevant to satellite-based navigation and communication systems, as fluctuations in ionospheric parameters can degrade signal integrity and reliability. In this study, data were obtained from multiple sources, including OMNIWeb for parameters like Dst, Kp, Bz, Electric Field, and solar wind pressure, GUVI for O/N₂ ratio maps, and TEC data from low-, mid-, and high-latitude stations available on the IONOLAB website. Additional Equatorial Electrojet (EEJ) and geomagnetic data were acquired from INTERMAGNET. The methodology involved comparing storm-affected data from April 22 to April 26 with quiet days in April 2023, using statistical and wavelet analysis to assess variations in parameters like TEC, O/N₂ ratio, and geomagnetic indices. The results show pronounced fluctuations in TEC and other ionospheric parameters during the main phase of the storm, with spatial variations observed across latitudes, highlighting the global response of the ionosphere to geomagnetic disturbances. The findings underline the storm’s significant impact on ionospheric composition, particularly in mid- and high-latitude regions, which correlates with increased GNSS signal interference in these areas. This study contributes to understanding the ionosphere’s response to geomagnetic activity, emphasizing the need for robust models to predict and mitigate space weather effects on GNSS-dependent technologies.Keywords: geomagnetic storms, ionospheric disturbances, space weather effects, magnetosphere-ionopheric coupling
Procedia PDF Downloads 173567 Identifying and Prioritizing Critical Success Factors (Csfs) in Retaining and Developing Knowledge Workers in Oil and Gas Project–Based Companies
Authors: Ehsan Samimi, Mohammaa Ali Shahosseeni, Ali Abasltian, Shahriar Shafaghi
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Background/Objectives: Voluntary turnover and early retirement request by specialists and experienced people in project-based organizations (PBO) has caused many problems in finding suitable experts to execute the projects. Methods/Statistical analysis: The present study is a descriptive and applied research. Research population consists of KWs in oil and gas PBO. The engineers in these organizations were considered as research sample. Interviews and questionnaire were used to gather information. Interviews with experts were used to identify factors and questionnaires were utilized to identify the importance and prioritization. 72 factors were identified and categorized into 9 groups within organizational and HR initiative levels. Results: Results of the research indicate the priority of each group of factors according to the proposed model in the view of KWs in oil, gas and petrochemical industries. On this basis, the following factors have the highest effect ratio based on the respondents’ point of view: 1. knowledge management 2. Performance appraisal system 3. Communication 4.Training and development 5.Job design and analysis 6. Employment policies 7. Career planning 8. Project/organizational factors 9. Salary and rewards. Additionally, in each group the priority of effective sub-factors has been identified as the result of the research .The results support the definitions of KWs and influence of factors examined and specified by similar studies in retention and development of KWs. The high importance of knowledge management and low rank for salary and rewards can be mentioned as example in this regard. Despite the priority of each group of factors the uniqueness of the result is due to identification of effective factors in the specific industry (oil and gas) and type of organization (PBO). Conclusion/Application: The findings of present study can be used to devise plans for retaining and developing KWs in PBO especially in oil and gas industry.Keywords: project–based organizations, knowledge workers, HR management, turnover, retaining and developing employees
Procedia PDF Downloads 2963566 Reducing Component Stress during Encapsulation of Electronics: A Simulative Examination of Thermoplastic Foam Injection Molding
Authors: Constantin Ott, Dietmar Drummer
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The direct encapsulation of electronic components is an effective way of protecting components against external influences. In addition to achieving a sufficient protective effect, there are two other big challenges for satisfying the increasing demand for encapsulated circuit boards. The encapsulation process should be both suitable for mass production and offer a low component load. Injection molding is a method with good suitability for large series production but also with typically high component stress. In this article, two aims were pursued: first, the development of a calculation model that allows an estimation of the occurring forces based on process variables and material parameters. Second, the evaluation of a new approach for stress reduction by means of thermoplastic foam injection molding. For this purpose, simulation-based process data was generated with the Moldflow simulation tool. Based on this, component stresses were calculated with the calculation model. At the same time, this paper provided a model for estimating the forces occurring during overmolding and derived a solution method for reducing these forces. The suitability of this approach was clearly demonstrated and a significant reduction in shear forces during overmolding was achieved. It was possible to demonstrate a process development that makes it possible to meet the two main requirements of direct encapsulation in addition to a high protective effect.Keywords: encapsulation, stress reduction, foam-injection-molding, simulation
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