Search results for: high dose rate brachytherapy

Authors: Hafiz Gulfam Ahmad, Chuangdong Li, Zeeshan Ahmad

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In this paper, we proposed a parallel IDS and honeypot based approach to detect and analyze the unknown and known attack taxonomy for improving the IDS performance and protecting the network from intruders. The main theme of our approach is to record and analyze the intruder activities by using both the low and high interaction honeypots. Our architecture aims to achieve the required goals by combing signature based IDS, honeypots and generate the new signatures. The paper describes the basic component, design and implementation of this approach and also demonstrates the effectiveness of this approach reducing the probability of network attacks.

Keywords: network security, intrusion detection, honeypot, snort, nmap

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Authors: Hachul Jung, Ahee Kim, Sanghoon Lee, Dahye Kwon, Songwoo Yoon, Jinhee Moon

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We fabricated a wearable patch device including novel patch type flexible dry electrode based on carbon nanofibers (CNFs) and silicone-based elastomer (MED 6215) for real-time ECG monitoring. There are many methods to make flexible conductive polymer by mixing metal or carbon-based nanoparticles. In this study, CNFs are selected for conductive nanoparticles because carbon nanotubes (CNTs) are difficult to disperse uniformly in elastomer compare with CNFs and silver nanowires are relatively high cost and easily oxidized in the air. Wearable patch is composed of 2 parts that dry electrode parts for recording bio signal and sticky patch parts for mounting on the skin. Dry electrode parts were made by vortexer and baking in prepared mold. To optimize electrical performance and diffusion degree of uniformity, we developed unique mixing and baking process. Secondly, sticky patch parts were made by patterning and detaching from smooth surface substrate after spin-coating soft skin adhesive. In this process, attachable and detachable strengths of sticky patch are measured and optimized for them, using a monitoring system. Assembled patch is flexible, stretchable, easily skin mountable and connectable directly with the system. To evaluate the performance of electrical characteristics and ECG (Electrocardiography) recording, wearable patch was tested by changing concentrations of CNFs and thickness of the dry electrode. In these results, the CNF concentration and thickness of dry electrodes were important variables to obtain high-quality ECG signals without incidental distractions. Cytotoxicity test is conducted to prove biocompatibility, and long-term wearing test showed no skin reactions such as itching or erythema. To minimize noises from motion artifacts and line noise, we make the customized wireless, light-weight data acquisition system. Measured ECG Signals from this system are stable and successfully monitored simultaneously. To sum up, we could fully utilize fabricated wearable patch devices for real-time ECG monitoring easily.

Keywords: carbon nanofibers, ECG monitoring, flexible dry electrode, wearable patch

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Authors: S. Agheb, G. Ledwich, G.Walker, Z.Tong

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Frequency control has become more of concern for reliable operation of interconnected power systems due to the integration of low inertia renewable energy sources to the grid and their volatility. Also, in case of a sudden fault, the system has less time to recover before widespread blackouts. Electric Vehicles (EV)s have the potential to cooperate in the Emergency Frequency Regulation (EFR) by a nonlinear control of the power system in case of large disturbances. The time is not adequate to communicate with each individual EV on emergency cases, and thus, an aggregate model is necessary for a quick response to prevent from much frequency deviation and the occurrence of any blackout. In this work, an aggregate of EVs is modelled as a big virtual battery in each area considering various aspects of uncertainty such as the number of connected EVs and their initial State of Charge (SOC) as stochastic variables. A control law was proposed and applied to the aggregate model using Lyapunov energy function to maximize the rate of reduction of total kinetic energy in a two-area network after the occurrence of a fault. The control methods are primarily based on the charging/ discharging control of available EVs as shunt capacity in the distribution system. Three different cases were studied considering the locational aspect of the model with the virtual EV either in the center of the two areas or in the corners. The simulation results showed that EVs could help the generator lose its kinetic energy in a short time after a contingency. Earlier estimation of possible contributions of EVs can help the supervisory control level to transmit a prompt control signal to the subsystems such as the aggregator agents and the grid. Thus, the percentage of EVs contribution for EFR will be characterized in the future as the goal of this study.

Keywords: emergency frequency regulation, electric vehicle, EV, aggregation, Lyapunov energy function

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Authors: Mona Hejazi, Ali Motie Nasrabadi

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Epilepsy is a persistent neurological disorder that affects more than 50 million people worldwide. Hence, there is a necessity to introduce an efficient prediction model for making a correct diagnosis of the epileptic seizure and accurate prediction of its type. In this study we consider how the Effective Connectivity (EC) patterns obtained from intracranial Electroencephalographic (EEG) recordings reveal information about the dynamics of the epileptic brain and can be used to predict imminent seizures, as this will enable the patients (and caregivers) to take appropriate precautions. We use this definition because we believe that effective connectivity near seizures begin to change, so we can predict seizures according to this feature. Results are reported on the standard Freiburg EEG dataset which contains data from 21 patients suffering from medically intractable focal epilepsy. Six channels of EEG from each patients are considered and effective connectivity using Directed Transfer Function (DTF) and Granger Causality (GC) methods is estimated. We concentrate on effective connectivity standard deviation over time and feature changes in five brain frequency sub-bands (Alpha, Beta, Theta, Delta, and Gamma) are compared. The performance obtained for the proposed scheme in predicting seizures is: average prediction time is 50 minutes before seizure onset, the maximum sensitivity is approximate ~80% and the false positive rate is 0.33 FP/h. DTF method is more acceptable to predict epileptic seizures and generally we can observe that the greater results are in gamma and beta sub-bands. The research of this paper is significantly helpful for clinical applications, especially for the exploitation of online portable devices.

Keywords: effective connectivity, Granger causality, directed transfer function, epilepsy seizure prediction, EEG

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Authors: Najlae Bendou, Jean-Jacques Lilti, Khalid Elbadraoui

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In this paper, we examine stock market integration of emerging markets around the global financial turmoil of 2007-2008. Following Pukthuanthong and Roll (2009), we measure the integration of 46 emerging countries using the adjusted R-square from the regression of each country's daily index returns on global factors extracted from the covariance matrix computed using dollar-denominated daily index returns of 17 developed countries. Our sample surrounds the global financial crisis and ranges between 2000 and 2018. We analyze results using four cohorts of emerging countries: East Asia & Pacific and South Asia, Europe & Central Asia, Latin America & Caribbean, Middle East & Africa. We find that the level of integration of emerging countries increases at the commencement of the crisis and during the booming phase of the business cycles. It reaches a maximum point in the middle of the crisis and then tends to revert to its pre-crisis level. This pattern tends to be common among the four geographic zones investigated in this study. Finally, we investigate the determinants of stock market integration of emerging countries in our sample using panel regressions. Our results suggest that the degree of stock market integration of these countries should be put into perspective by some macro-economic factors, such as the size of the equity market, school enrollment rate, international liquidity level, stocks traded volume, tax revenue level, imports and exports volumes.

Keywords: correlations, determinants of integration, diversification, emerging markets, financial crisis, integration, markets co-movement, panel regressions, r-square, stock markets

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Authors: Kristy Howells, Catherine Meehan

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This position paper presents current research findings into the proposed gap between teachers’ and practitioners’ thinking and acting about physical activity health and well-being in childhood. Within the new Primary curriculum, there is a focus on sustained physical activity within a Physical Education and healthy lifestyles in Personal, Health, Social and Emotional lessons, but there is no curriculum guidance about what sustained physical activity is and how it is defined. The current health guidance on birth to five suggests that children should not be inactive for long periods and specify light and energetic activities, however there is the a suggested period of time per day for young children to achieve, but the guidance does not specify how this should be measured. The challenge therefore for teachers and practitioners is their own confidence and understanding of what “good / moderate intensity” physical activity and healthy living looks like for children and the children understanding what they are doing. There is limited research about children from birth to eight years and also the perceptions and attitudes of those who work with this age group of children, however it was found that children at times can identify different levels of activity and it has been found that children can identify healthy foods and good choices for healthy living at a basic level. Authors have also explored teachers’ beliefs about teaching and learning and found that teachers could act in accordance to their beliefs about their subject area only when their subject knowledge, understanding and confidence of that area is high. It has been proposed that confidence and competence of practitioners and teachers to integrate ‘well-being’ within the learning settings has been reported as being low. This may be due to them not having high subject knowledge. It has been suggested that children’s life chances are improved by focusing on well-being in their earliest years. This includes working with parents and families, and being aware of the environmental contexts that may impact on children’s wellbeing. The key is for practitioners and teachers to know how to implement these ideas effectively as these key workers have a profound effect on young children as role models and due to the time of waking hours spent with them. The position paper is part of a longitudinal study at Canterbury Christ Church University and currently we will share the research findings from the initial questionnaire (online, postal, and in person) that explored and evaluated the knowledge, competence and confidence levels of practitioners and teachers as to the structure and planning of sustained physical activity and healthy lifestyles and how this progresses with the children’s age.

Keywords: health, perceptions, physical activity, well-being

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Authors: Majda El Moufarej

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Higher education plays a central role in socio-economic development. However, with the wave of change mainly due to the extensive use of technology in the workplace, the rate of unemployment among graduates rises because they lack the appropriate competencies and skills currently required in professional life. This situation has led higher education institutions worldwide to reconsider their missions, strategic planning, and curricula, among other elements to redress the image of the university as expected. When it comes to practice, there are many obstacles that hinder the achievement of the expected objectives, especially in public universities with free access, as in the case of Morocco. Nevertheless, huge efforts have been made by educational managers to improve the quality of education by focusing on the issue of pedagogical approaches, where university teachers assume more responsibility to save the situation. In this paper, the focus will be placed on the issue of pedagogical approaches to be adopted, depending on the nature of the subject, the size of the class, the available equipment, the students’ level and degree of motivation. Before elaborating on this idea, it may be more insightful to begin by addressing another variable, which concerns the new role of university teachers and their qualification in pedagogical competence. Then, the discussion will revolve around five pedagogical approaches currently adopted in western universities and the focus will be exclusively placed on the one which is called “the Systematic Approach to course Design”, due to its crucial relevance in the teaching of subjects in the schools of humanities, as it can guide the teacher in the development of an explicit program for purposeful teaching and learning. The study is based on a qualitative method, and the findings will be analyzed and followed by some recommendations about how to overcome difficulties in teaching large groups, while transmitting the relevant knowledge and skills on demand in the workplace.

Keywords: higher education, public universities, pedagogical approaches, pedagogical competence

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Authors: Veronique Troch, Wouter Van der Borght, Véronique De Bleeker, Bram Marynissen, Nathan Van der Eecken, Gijs Du Laing

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Among the challenges associated with increased urban food production are health risks from food contamination, due to the higher pollution loads in urban areas, compared to rural sites. Therefore, the risks posed by industrial or traffic pollution of locally grown food, was defined as one of five high-priority issues of urban agriculture requiring further investigation. The impact of air pollution on urban horticulture is the subject of this study. More particular, this study focuses on the atmospheric deposition of trace metals on leaf vegetables cultivated in the city of Ghent, Belgium. Ghent is a particularly interesting study site as it actively promotes urban agriculture. Plants accumulate heavy metals by absorption from contaminated soils and through deposition on parts exposed to polluted air. Accumulation of trace metals in vegetation grown near roads has been shown to be significantly higher than those grown in rural areas due to traffic-related contaminants in the air. Studies of vegetables demonstrated, that the uptake and accumulation of trace metals differed among crop type, species, and among plant parts. Studies on vegetables and fruit trees in Berlin, Germany, revealed significant differences in trace metal concentrations depending on local traffic, crop species, planting style and parameters related to barriers between sampling site and neighboring roads. This study aims to supplement this scarce research on heavy metal accumulation in urban horticulture. Samples from leaf vegetables were collected from different sites, including allotment gardens, in Ghent. Trace metal contents on these leaf vegetables were analyzed by ICP-MS (inductively coupled plasma mass spectrometry). In addition, precipitation on each sampling site was collected by NILU-type bulk collectors and similarly analyzed for trace metals. On one sampling site, different parameters which might influence trace metal content in leaf vegetables were analyzed in detail. These parameters are distance of planting site to the nearest road, barriers between planting site and nearest road, and type of leaf vegetable. For comparison, a rural site, located farther from city traffic and industrial pollution, was included in this study. Preliminary results show that there is a high correlation between trace metal content in the atmospheric deposition and trace metal content in leaf vegetables. Moreover, a significant higher Pb, Cu and Fe concentration was found on spinach collected from Ghent, compared to spinach collected from a rural site. The distance of planting site to the nearest road significantly affected the accumulation of Pb, Cu, Mo and Fe on spinach. Concentrations of those elements on spinach increased with decreasing distance between planting site and the nearest road. Preliminary results did not show a significant effect of barriers between planting site and the nearest road on accumulation of trace metals on leaf vegetables. The overall goal of this study is to complete and refine existing guidelines for urban gardening to exclude potential health risks from food contamination. Accordingly, this information can help city governments and civil society in the professionalization and sustainable development of urban agriculture.

Keywords: atmospheric deposition, leaf vegetables, trace metals, traffic pollution, urban agriculture

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Authors: Emery Jr. Coppola

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Water resources are being depleted and degraded at an alarming and non-sustainable rate worldwide. In some areas, it is progressing more slowly. In other areas, irreversible damage has already occurred, rendering regions largely unsuitable for human existence with destruction of the environment and the economy. Today, 2.5 billion people or 36 percent of the world population live in water-stressed areas. The convergence of factors that created this global water crisis includes local, regional, and global failures. In this paper, a survey of some of these factors is presented. They include abuse of political power and regulatory acquiescence, improper planning and design, ignoring good science and models, systemic failures, and division between the powerful and the powerless. Increasing water demand imposed by exploding human populations and growing economies with short-falls exacerbated by climate change and continuing water quality degradation will accelerate this growing water crisis in many areas. Without regional measures to improve water efficiencies and protect dwindling and vulnerable water resources, environmental and economic displacement of populations and conflict over water resources will only grow. Perhaps more challenging, a global commitment is necessary to curtail if not reverse the devastating effects of climate change. Factors will be illustrated by real-world examples, followed by some partial solutions offered by water experts for helping to mitigate the growing water crisis. These solutions include more water efficient technologies, education and incentivization for water conservation, wastewater treatment for reuse, and improved data collection and utilization.

Keywords: climate change, water conservation, water crisis, water technologies

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Authors: Lalita Panchal, Zulfiya Sheikh

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Fluoride is essential for teeth and bones development not only for human beings but also for animals. But excess intake of fluoride causes harmful effects on health. Fluorosis is a worldwide health hazard and India is also one of the endemic countries. Udaipur district of Rajasthan is also prone to fluorosis and superphosphate industries are aggravating fluoride toxicity in this area. Grazing fields for animals in the close vicinity of the industries, fodder and water are fluoride contaminated. Fluoride toxicity in the form of dental fluorosis was observed in domestic animals, inhabiting industrial area near Udaipur, where superphosphate fertilizer plants are functioning and releasing fluoride and fumes and effluents into the surroundings. These fumes and gases directly affect the vegetation of grazing field, thus allowing entry of fluoride into the food chain. A survey was conducted in this area to assess the severity of fluorosis, in 2015-16. It was a house to house survey and animal owners were asked for their fodder and water supply. Anterior teeth of the animal were observed. Domestic animals exhibited mild to severe signs of dental fluorosis. Teeth showed deep brown staining, patches, lines and abrasions. Even immature animals were affected badly. Most of the domestic animals were affected, but goats of this area showed chronic symptoms of fluorosis. Due to abrasion of teeth and paining teeth their chewing or grazing capacity and appetite reduced. Eventually, it reduced the life span of animals and increased the mortality rate.

Keywords: domestic animals, fluoride toxicity, industrial fluorosis, superphosphate fertilizers

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Authors: Anil F. Felek, Mehmet M. Ozcan, Faruk Akyazi

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Volatile oils of medicinal and aromatic plants are important for managing nematological problems in agriculture. In present study, volatile oils extracted from five medicinal and aromatic plants including Origanum onites (flower+steam+leaf), Salvia officinalis (leaf), Lippia citriodora (leaf+seed), Mentha spicata (leaf) and Mentha longifolia (leaf) were tested for egg hatching inhibition activity against root-knot nematode Meloidogyne hapla under laboratory conditions. The essential oils were extracted using water distillation method with a Clevenger system. For the homogenisation process of the oils, 2% gum arabic solution was used and 4 µl oils was added into 1ml filtered gum arabic solution to prepare the last stock solution. 5 ml of stock solution and 1 ml of M. hapla egg suspension (about 100 eggs) were added into petri dishes. Gum arabic solution was used as control. Seven days after exposure to oils at room temperature (26±2 °C), the cumulative hatched and unhatched eggs were counted under 40X inverted light microscope and Abbott’s formula was used to calculate egg hatching inhibition rates. As a result, the highest inhibition rate was found as 54% for O. onites. In addition, the other inhibition rates varied as 31.4%, 21.6%, 23.8%, 25.67% for the other plants, S. officinalis, M. longifolia, M. spicata and L. citriodora, respectively. Carvacrol was found as the main component (68.8%) of O. onites followed by Thujone 27.77% for S. officinalis, I-Menthone 76.92% for M. longifolia, Carvone 27.05% for M. spicata and Citral 19.32% for L. citriodora.

Keywords: egg hatching, Meloidogyne hapla, medicinal and aromatic plants, root-knot nematodes, volatile oils

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Authors: Natalia Kalinowska

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The adoption of the General Data Protection Regulation, (GDPR) finished the four-year work of the European Commission in this area in the European Union. Considering far-reaching changes, which will be applied by GDPR, the European legislator envisaged two-year transitional period. Member states and companies have to prepare for a new regulation until 25 of May 2018. The idea, which becomes a new look at an attitude to data protection in the European Union is risk-based approach. So far, as a result of implementation of Directive 95/46/WE, in many European countries (including Poland) there have been adopted very particular regulations, specifying technical and organisational security measures e.g. Polish implementing rules indicate even how long password should be. According to the new approach from May 2018, controllers and processors will be obliged to apply security measures adequate to level of risk associated with specific data processing. The risk in GDPR should be interpreted as the likelihood of a breach of the rights and freedoms of the data subject. According to Recital 76, the likelihood and severity of the risk to the rights and freedoms of the data subject should be determined by reference to the nature, scope, context and purposes of the processing. GDPR does not indicate security measures which should be applied – in recitals there are only examples such as anonymization or encryption. It depends on a controller’s decision what type of security measures controller considered as sufficient and he will be responsible if these measures are not sufficient or if his identification of risk level is incorrect. Data protection regulation indicates few levels of risk. Recital 76 indicates risk and high risk, but some lawyers think, that there is one more category – low risk/now risk. Low risk/now risk data processing is a situation when it is unlikely to result in a risk to the rights and freedoms of natural persons. GDPR mentions types of data processing when a controller does not have to evaluate level of risk because it has been classified as „high risk” processing e.g. processing on a large scale of special categories of data, processing with using new technologies. The methodology will include analysis of legal regulations e.g. GDPR, the Polish Act on the Protection of personal data. Moreover: ICO Guidelines and articles concerning risk based approach in GDPR. The main conclusion is that an appropriate risk assessment is a key to keeping data safe and avoiding financial penalties. On the one hand, this approach seems to be more equitable, not only for controllers or processors but also for data subjects, but on the other hand, it increases controllers’ uncertainties in the assessment which could have a direct impact on incorrect data protection and potential responsibility for infringement of regulation.

Keywords: general data protection regulation, personal data protection, privacy protection, risk based approach

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Authors: Felipe Riveros, Ricardo Alvarez, Claudia Rahmann, Rodrigo Moreno

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Around the world, many countries have committed to a decarbonization of their electricity system. Under this global drive, converter-interfaced generators (CIG) such as wind and photovoltaic generation appear as cornerstones to achieve these energy targets. Despite its benefits, an increasing use of CIG brings several technical challenges in power systems, especially from a stability viewpoint. Among the key differences are limited short circuit current capacity, inertia-less characteristic of CIG, and response times within the electromagnetic timescale. Along with the integration of CIG into the power system, one enabling technology for the energy transition towards low-carbon power systems is battery energy storage systems (BESS). Because of the flexibility that BESS provides in power system operation, its integration allows for mitigating the variability and uncertainty of renewable energies, thus optimizing the use of existing assets and reducing operational costs. Another characteristic of BESS is that they can also support power system stability by injecting reactive power during the fault, providing short circuit currents, and delivering fast frequency response. However, most methodologies for sizing and allocating BESS in power systems are based on economic aspects and do not exploit the benefits that BESSs can offer to system stability. In this context, this paper presents a methodology for determining the optimal allocation of battery energy storage systems (BESS) in weak power systems with high levels of CIG. Unlike traditional economic approaches, this methodology incorporates stability constraints to allocate BESS, aiming to mitigate instability issues arising from weak grid conditions with low short-circuit levels. The proposed methodology offers valuable insights for power system engineers and planners seeking to maintain grid stability while harnessing the benefits of renewable energy integration. The methodology is validated in the reduced Chilean electrical system. The results show that integrating BESS into a power system with high levels of CIG with stability criteria contributes to decarbonizing and strengthening the network in a cost-effective way while sustaining system stability. This paper potentially lays the foundation for understanding the benefits of integrating BESS in electrical power systems and coordinating their placements in future converter-dominated power systems.

Keywords: battery energy storage, power system stability, system strength, weak power system

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Authors: Bartosz Olszanski, Zbigniew Nosal, Jacek Rokicki

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An experimental study of cold-jet (nitrogen) reaction control jet system has been carried out to investigate the flow control efficiency for low to moderate jet pressure ratios (total jet pressure p0jet over free stream static pressure in the wind tunnel p∞) and different angles of attack for infinite Mach number equal to 2. An investigation of jet influence was conducted on a flat plate geometry placed in the test section of intermittent supersonic wind tunnel of Department of Aerodynamics, WUT. Various convergent jet nozzle geometries to obtain different jet momentum ratios were tested on the same test model geometry. Surface static pressure measurements, Schlieren flow visualizations (using continuous and photoflash light source), load cell measurements gave insight into the supersonic crossflow interaction for different jet pressure and jet momentum ratios and their influence on the efficiency of side jet control as described by the amplification factor (actual to theoretical net force generated by the control nozzle). Moreover, the quasi-steady numerical simulations of flow through the same wind tunnel geometry (convergent-divergent nozzle plus test section) were performed using ANSYS Fluent basing on Reynolds-Averaged Navier-Stokes (RANS) solver incorporated with k-ω Shear Stress Transport (SST) turbulence model to assess the possible spurious influence of test section walls over the jet exit near field area of interest. The strong bow shock, barrel shock, and Mach disk as well as lambda separation region in front of nozzle were observed as images taken by high-speed camera examine the interaction of the jet and the free stream. In addition, the development of large-scale vortex structures (counter-rotating vortex pair) was detected. The history of complex static pressure pattern on the plate was recorded and compared to the force measurement data as well as numerical simulation data. The analysis of the obtained results, especially in the wake of the jet showed important features of the interaction mechanisms between the lateral jet and the flow field.

Keywords: flow visualization techniques, pressure measurements, reaction control jet, supersonic cross flow

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Authors: Sadia Ameen, M. Nazim, Hyumg-Kee Seo, Hyung-Shik Shin

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TiO2 nanotube (NT) arrays were grown on titanium (Ti) foil substrate by electrochemical anodic oxidation and utilized as working electrode to fabricate a highly sensitive and reproducible chemical sensor for the detection of harmful phenyl hydrazine chemical. The fabricated chemical sensor based on TiO2 NT arrays electrode exhibited high sensitivity of ~40.9 µA.mM-1.cm-2 and detection limit of ~0.22 µM with short response time (10s).

Keywords: TiO2 NT, phenyl hydrazine, chemical sensor, sensitivity, electrocatalytic properties

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Authors: S. S. Sravanthi, Swati Ghosh Acharyya

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Automotive light weighting is of major prominence in the current times due to its contribution in improved fuel economy and reduced environmental pollution. Various arc welding technologies are being employed in the production of automobile components with reduced weight. The present study is of practical importance since it involves preferential substitution of Zinc coated mild steel with a light weight alloy such as 6061 Aluminium by means of Gas Metal Arc Welding (GMAW) – Brazing technique at different processing parameters. However, the fabricated joints have shown the generation of Al – Fe layer at the interfacial regions which was confirmed by the Scanning Electron Microscope and Energy Dispersion Spectroscopy. These Al-Fe compounds not only affect the mechanical strength, but also predominantly deteriorate the corrosion resistance of the joints. Hence, it is essential to understand the phases formed in this layer and their crystal structure. Micro area X - ray diffraction technique has been exclusively used for this study. Moreover, the crevice corrosion analysis at the joint interfaces was done by exposing the joints to 5 wt.% FeCl₃ solution at regular time intervals as per ASTM G 48-03. The joints have shown a decreased crevice corrosion resistance with increased heat intensity. Inner surfaces of welds have shown severe oxide cracking and a remarkable weight loss when exposed to concentrated FeCl₃. The weight loss was enhanced with decreased filler wire feed rate and increased heat intensity. 

Keywords: automobiles, welding, corrosion, lap joints, Micro XRD

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Authors: Bernd Engel, Sara Salman Hassan Al-Maeeni

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A substantial amount of natural resources are nowadays consumed at a growing rate, as humans all over the world used materials obtained from the Earth. Machinery manufacturing industry is one of the major resource consumers on a global scale. Even though the incessant finding out of the new material, metals, and resources, it is urgent for the industry to develop methods to use the Earth's resources intelligently and more sustainable than before. Re-engineering of machine tools regarding design and failure analysis is an approach whereby out-of-date machines are upgraded and returned to useful life. To ensure the reliable future performance of the used machine components, it is essential to investigate the machine component failure through the material, design, and surface examinations. This paper presents an experimental approach aimed at inspecting the shaft of the rotary draw bending machine as a case to study. The testing methodology, which is based on the principle of the three-point bending test, allows assessing the shaft elastic behavior under loading. Furthermore, the shaft elastic characteristics include the maximum linear deflection, and maximum bending stress was determined by using an analytical approach and finite element (FE) analysis approach. In the end, the results were compared with the ones obtained by the experimental approach. In conclusion, it is seen that the measured bending deflection and bending stress were well close to the permissible design value. Therefore, the shaft can work in the second life cycle. However, based on previous surface tests conducted, the shaft needs surface treatments include re-carburizing and refining processes to ensure the reliable surface performance.

Keywords: deflection, FE analysis, shaft, stress, three-point bending

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Authors: Hagos Abraham, Solomon Gizaw, Mengistu Urge

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A sound breeding objective is the basis for genetic improvement in overall economic merit of farm animals. Begait goat is one of the identified breeds in Ethiopia, which is a multipurpose breed as it serves as source of cash income and source of food (meat and milk). Despite its importance, no formal breeding objectives exist for Begait goat. The objective of the present study was to identify breeding objectives for the breed through two approaches: using own-flock ranking experiment and developing deterministic bio-economic models as a preliminary step towards designing sustainable breeding programs for the breed. In the own-flock ranking experiment, a total of forty five households were visited at their homesteads and were asked to select, with reasons, the first best, second best, third best and the most inferior does from their own flock. Age, previous reproduction and production information of the identified animals were inquired; live body weight and some linear body measurements were taken. The bio-economic model included performance traits (weights, daily weight gain, kidding interval, litter size, milk yield, kid mortality, pregnancy and replacement rates) and economic (revenue and costs) parameters. It was observed that there was close agreement between the farmers’ ranking and bio-economic model results. In general, the results of the present study indicated that Begait goat owners could improve performance of their goats and profitability of their farms by selecting for litter size, six month weight, pre-weaning kid survival rate and milk yield.

Keywords: bio-economic model, economic parameters, own-flock ranking, performance traits

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Authors: A. Larrousi, M. Elkeurti, K. Amara, M. Zemouli, L. H. Coudert, I. R. Medvedev, F. C. De Lucia, Atsuko Maeda, R. W. C. McKellar, D. Appadoo

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Experimental and theoretical investigations of the microwave and far infrared spectra of CH3COD are reported. Two hundred twelve lines were identified in the far infrared spectrum recorded using the Canadian synchrotron radiation light source. Two thousand one hundred and sixty-eight lines in vt=0,1 and 216 in vt=2 have been measured in the microwave spectrum obtained using the fast scan submillimeter spectroscopic technique. A global analysis of the new data and of already available microwave lines has been carried out and yielded values for rotation–torsion parameters. The unitless weighted standard deviation of the fit is 1.6. 46 parameters and 216 lines were identified.

Keywords: CH3COD, torsion, the microwave spectra, far infrared spectra high resolution

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Authors: Jing Li, Li Jin, Fulin Wang, Jie Dong, Wenjiang Ding

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Mg-Li dual-phase alloy exhibits better combination of yield strength and elongation than the Mg single-phase alloy. To exploit its deformation behavior, the deformation mechanisms of Mg-2Gd alloy with or without Li addition, i.e., Mg-6Li-2Gd and Mg-2Gd alloy, have been studied at both microscale and mesoscale. EBSD-assisted slip trace, twin trace, and texture evolution analysis show that the α-Mg phase of Mg-6Li-2Gd alloy exhibits different microscopic deformation mechanisms with the Mg-2Gd alloy, i.e., mainly prismatic slip in the former one, while basal slip, prismatic slip and extension twin in the latter one. Further Schmid factor analysis results attribute this different intra-phase deformation mechanisms to the higher critical resolved shear stress (CRSS) value of extension twin and lower ratio of CRSSprismatic /CRSSbasal in the α-Mg phase of Mg-6Li-2Gd alloy. Additionally, Li addition can induce dual-phase microstructure in the Mg-6Li-2Gd alloy, leading to the formation of hetero-deformation induced (HDI) stress at the mesoscale. This can be evidenced by the hysteresis loops appearing during the loading-unloading-reloading (LUR) tensile tests and the activation of multiple slip activity in the α-Mg phase neighboring β-Li phase. The Mg-6Li-2Gd alloy shows higher yield strength is due to the harder α-Mg phase arising from solid solution hardening of Li addition, as well asthe strengthening of soft β-Li phase by the HDI stress during yield stage. Since the strain hardening rate of Mg-6Li-2Gd alloy is lower than that of Mg-2Gd alloy after ~2% strain, which is partly due to the weak contribution of HDI stress, Mg-6Li-2Gd alloy shows no obvious increase of uniform elongation than the Mg-2Gd alloy.But since the β-Li phase is effective in blunting the crack tips, the Mg-6Li-2Gd alloy shows ununiform elongation, which, thus, leads to the higher total elongation than the Mg-2Gd alloy.

Keywords: Mg-Li-Gd dual-phase alloy, phase boundary, HDI stress, dislocation slip activity, mechanical properties

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Authors: Zohreh Bayat, Dariush Minai-Tehrani

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Lipases constitute one of the most important groups of industrial enzymes that catalyze the hydrolysis of triacylglycerol to glycerol and fatty acids. Muscarinic antagonist relieves smooth muscle spasm of the gastrointestinal tract and effect on the cardiovascular system. In this research, the effect of a muscarinic antagonist on the lipase activity of Pseudomonas aeruginosa was studied. Lineweaver–Burk plot showed that the drug inhibited the enzyme by competitive inhibition. The IC50 value (60 uM) and Ki (30 uM) of the drug revealed the drug bound to the enzyme with high affinity. Determination of enzyme activity in various pH and temperature showed that the maximum activity of lipase was at pH 8 and 60°C both in presence and absence of the drug.

Keywords: bacteria, inhibition, kinetics, lipase

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Authors: Youssef. K. A. Abdalhafid, Ezaldin A. M. Mohammed, Masoud M. M. Zatout

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This study described the changes in the liver of Uromastyx acanthinura (Bell, 1825) males and females during hibernation and activity seasons. The results revealed that, hibernation causes increase fatty liver and pigment cells with abundant damage, comparing with nearly normal structure and less fatty liver after the hibernation with almost normal pattern. Genomic DNA showed apparent separation during hibernation. Also, caspase 3 and caspase 7 activity reached a high level in the liver tissue during hibernation comparing with activity season.

Keywords: histological liver, DNA fragmentation, hibernation, caspase 3 and caspase 7

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Authors: Solmaz Jahed Shiran, John Hearne, Tayebeh Saghapour

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Daily travel behavior is strongly influenced by the location of the places of residence, education, and employment. Hence a change in those locations due to a move or changes in an occupation leads to a change in travel behavior. Given the interventions of housing mobility and travel behaviors, the hypothesis is that a mobile housing market allows households to move as a result of any change in their life course, allowing them to be closer to central services, public transport facilities and workplace and hence reducing the time spent by individuals on daily travel. Conversely, household’s immobility may lead to longer commutes of residents, for example, after a change of a job or a need for new services such as schools for children who have reached their school age. This paper aims to investigate the association between residential mobility and travel behavior. The Victorian Integrated Survey of Travel and Activity (VISTA) data is used for the empirical analysis. Car ownership and journey to work time and distance of employed people are used as indicators of travel behavior. Change of usual residence within the last five years used to identify movers and non-movers. Statistical analysis, including regression models, is used to compare the travel behavior of movers and non-movers. The results show travel time, and the distance does not differ for movers and non-movers. However, this is not the case when taking into account the residence tenure-type. In addition, car ownership rate and number found to be significantly higher for non-movers. It is hoped that the results from this study will contribute to a better understanding of factors other than common socioeconomic and built environment features influencing travel behavior.

Keywords: journey to work, regression models, residential mobility, commute mode, car ownership

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Authors: L. Salomon, P. Sklenar

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The Andes hold the highest plant species diversity in the world. How this occurred is one of the most intriguing questions in studies addressing the origin and patterning of plant diversity worldwide. Recently, the explosive adaptive radiations found in high Andean groups have been pointed as triggers to this spectacular diversity. The Andes is the species-richest area for the biggest genus from the Asteraceae family: Senecio. There, the genus presents an incredible diversity of species, striking growth form variation, and large niche span. Even when some studies tried to disentangle the evolutionary story for some Andean species in Senecio, they obtained partially resolved and low supported phylogenies, as expected for recently radiated groups. The high-throughput sequencing (HTS) approaches have proved to be a powerful tool answering phylogenetic questions in those groups whose evolutionary stories are recent and traditional techniques like Sanger sequencing are not informative enough. Although these tools have been used to understand the evolution of an increasing number of Andean groups, nowadays, their scope has not been applied for Senecio. This project aims to contribute to a better knowledge of the mechanisms shaping the hyper diversity of Senecio in the Andean region, using HTS focusing on Senecio ser. Culcitium (Asteraceae), recently recircumscribed. Firstly, reconstructing a highly resolved and supported phylogeny, and after assessing the role of allopatric differentiation, hybridization, and genome duplication in the diversification of the group. Using the Hyb-Seq approach, combining target enrichment using Asteraceae COS loci baits and genome skimming, more than 100 new accessions were generated. HybPhyloMaker and HybPiper pipelines were used for the phylogenetic analyses, and another pipeline in development (Paralogue Wizard) was used to deal with paralogues. RAxML was used to generate gene trees and Astral for species tree reconstruction. Phyparts were used to explore as first step of gene tree discordance along the clades. Fully resolved with moderated supported trees were obtained, showing Senecio ser. Culcitium as monophyletic. Within the group, some species formed well-supported clades with morphologically related species, while some species would not have exclusive ancestry, in concordance with previous studies using amplified fragment length polymorphism (AFLP) showing geographical differentiation. Discordance between gene trees was detected. Paralogues were detected for many loci, indicating possible genome duplications; ploidy level estimation using flow cytometry will be carried out during the next months in order to identify the role of this process in the diversification of the group. Likewise, TreeSetViz package for Mesquite, hierarchical likelihood ratio congruence test using Concaterpillar, and Procrustean Approach to Cophylogeny (PACo), will be used to evaluate the congruence among different inheritance patterns. In order to evaluate the influence of hybridization and Incomplete Lineage Sorting (ILS) in each resultant clade from the phylogeny, Joly et al.'s 2009 method in a coalescent scenario and Paterson’s D-statistic will be performed. Even when the main discordance sources between gene trees were not explored in detail yet, the data show that at least to some degree, processes such as genome duplication, hybridization, and/or ILS could be involved in the evolution of the group.

Keywords: adaptive radiations, Andes, genome duplication, hybridization, Senecio

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Authors: Risna Wijayanti, Sumiati, Hanif Iswari

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This study aims to analyze the role of financial risk attitude as a mediation between financial knowledge and business growth. The ability of human resources in managing capital (financial literacy) can be a major milestone for a company's business to grow and build its competitive advantage. This study analyzed the important role of financial risk attitude in bringing about financial knowledge on corporate growth. There have been many discussions arguing that financial knowledge is one of the main abilities of corporate managers in determining the success of managing a company. However, a contrary argument of other scholars also enlightened that financial knowledge did not have a significant influence on corporate growth. This study used literatures' review to analyze whether there is another variable that can mediate the effect of financial knowledge toward corporate growth. Research mapping was conducted to analyze the concept of risk tolerance. This concept was related to people's risk aversion effects when making a decision under risk and the role of financial knowledge on changes in financial income. Understanding and managing risks and investments are complicated, in particular for corporate managers, who are always demanded to maintain their corporate growth. Substantial financial knowledge is extremely needed to identify and take accurate information for corporate financial decision-making. By reviewing several literature, this study hypothesized that financial knowledge of corporate managers would be meaningless without manager's courage to bear risks for taking favorable business opportunities. Therefore, the level of risk aversion from corporate managers will determine corporate action, which is a reflection of corporate-level investment behavior leading to attain corporate success or failure for achieving the company's expected growth rate.

Keywords: financial knowledge, financial risk attitude, corporate growth, risk tolerance

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Authors: V. K. Gupta, Tejeet Singh

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In many whisker reinforced composites, anisotropy may result due to material flow during processing operations such as forging, extrusion etc. The consequence of anisotropy, introduced during processing of disc material, has been investigated on the steady state creep deformations of the rotating disc. The disc material is assumed to undergo plastic deformations according to Hill’s anisotropic criterion. Steady state creep has been analyzed in a constant thickness rotating disc made of functionally graded 6061Al-SiCw (where the subscript ‘w’ stands for whisker) using Hill’s The content of reinforcement (SiCw) in the disc is assumed to decrease linearly from the inner to outer radius. The stresses and strain rates in the disc are estimated by solving the force equilibrium equation along with the constitutive equations describing multi-axial creep. The results obtained for anisotropic FGM disc have been compared with those estimated for isotropic FGM disc having the same average whisker content. The anisotropic constants, appearing in Hill’s yield criterion, have been obtained from the available experimental results. The results show that the presence of anisotropy reduces the tangential stress in the middle of the disc but near the inner and outer radii the tangential stress is higher when compared to isotropic disc. On the other hand, the steady state creep rates in the anisotropic disc are reduced significantly over the entire disc radius, with the maximum reduction observed at the inner radius. Further, in the presence of anisotropy the distribution of strain rate becomes relatively uniform over the entire disc, which may be responsible for reducing the extent of distortion in the disc.

Keywords: anisotropy, creep, functionally graded composite, rotating disc

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Authors: Biruk Wolde Eremacho

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The Kombolcha to Desse road, linking Addis Ababa with Northern Ethiopia towns traverses through one of the most difficult mountainous ranges in Ethiopia. The presence of loose unconsolidated materials (colluvium materials), highly weathered and fractured basalt rocks high relief, steep natural slopes, nature of geologic formations exposed along the road section, poor drainage conditions, occurrence of high seasonal rains, and seismically active nature of the region created favorable condition for slope instability in the area. Thus, keeping in mind all above points the present study was conceived to study in detail the slope stability condition of the area. It was realized that detailed slope stability studies along this road section are very necessary to identify critical slopes and to provide the best remedial measures to minimize the slope instability problems which frequently disrupt and endanger the traffic movement on this important road. For the present study based on the field manifestation of instability two most critical slope sections were identified for detailed slope stability analysis. The deterministic slope stability analysis approach was followed to perform the detailed slope stability analysis of the selected slope sections. Factor of safety for the selected slope sections was determined for the different anticipated conditions (i.e., static and dynamic with varied water saturations) using Slope/W and Slide software. Both static and seismic slope stability analysis were carried out and factor of safety was deduced for each anticipated conditions. In general, detailed slope stability analysis of the two critical slope sections reveals that for only static dry condition both the slopes sections would be stable. However, for the rest anticipated conditions defined by static and dynamic situations with varied water saturations both critical slope sections would be unstable. Moreover, the causes of slope instability in the study area are governed by different factors; therefore integrated approaches of remedial measures are more appropriate to mitigate the possible slope instability in the study area. Depending on site condition and slope stability analysis result four types of suitable preventive and remedial measures are recommended namely; proper managements of drainages, retaining structures, gabions, and managing steeply cut slopes.

Keywords: factor of safety, remedial measures, slope stability analysis, static and dynamic condition

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Authors: Gizem Eser Erdek

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This study is research on predicting the remaining life of industrial cutting tools used in the industrial production process with deep learning methods. When the life of cutting tools decreases, they cause destruction to the raw material they are processing. This study it is aimed to predict the remaining life of the cutting tool based on the damage caused by the cutting tools to the raw material. For this, hole photos were collected from the hole-drilling machine for 8 months. Photos were labeled in 5 classes according to hole quality. In this way, the problem was transformed into a classification problem. Using the prepared data set, a model was created with convolutional neural networks, which is a deep learning method. In addition, VGGNet and ResNet architectures, which have been successful in the literature, have been tested on the data set. A hybrid model using convolutional neural networks and support vector machines is also used for comparison. When all models are compared, it has been determined that the model in which convolutional neural networks are used gives successful results of a %74 accuracy rate. In the preliminary studies, the data set was arranged to include only the best and worst classes, and the study gave ~93% accuracy when the binary classification model was applied. The results of this study showed that the remaining life of the cutting tools could be predicted by deep learning methods based on the damage to the raw material. Experiments have proven that deep learning methods can be used as an alternative for cutting tool life estimation.

Keywords: classification, convolutional neural network, deep learning, remaining life of industrial cutting tools, ResNet, support vector machine, VggNet

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Authors: F. Boukli Hacene, W. Soufi, S. Ghalem

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Glaucoma disease is a progressive degenerative optic neuropathy, with irreversible visual field deficits and high eye pressure being one of the risk factors. Sulfonamides are carbonic anhydrase-II inhibitors that aim to decrease the secretion of aqueous humor by direct inhibition of this enzyme at the level of the ciliary processes. These drugs present undesirable effects that are difficult to accept by the patient. In our study, we are interested in the inhibition of carbonic anhydrase-II by different natural ligands (curcumin analogues) using molecular modeling methods using molecular operating environment (MOE) software to predict their interaction with this enzyme.

Keywords: carbonic anhydrase-II, curcumin analogues, drug research, molecular modeling

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Authors: Idrissa Kayijuka

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The logistic regression and Cox regression models (proportional hazard model) at present are being employed in the analysis of prospective epidemiologic research looking into risk factors in their application on chronic diseases. However, a theoretical relationship between the two models has been studied. By definition, Cox regression model also called Cox proportional hazard model is a procedure that is used in modeling data regarding time leading up to an event where censored cases exist. Whereas the Logistic regression model is mostly applicable in cases where the independent variables consist of numerical as well as nominal values while the resultant variable is binary (dichotomous). Arguments and findings of many researchers focused on the overview of Cox and Logistic regression models and their different applications in different areas. In this work, the analysis is done on secondary data whose source is SPSS exercise data on BREAST CANCER with a sample size of 1121 women where the main objective is to show the application difference between Cox regression model and logistic regression model based on factors that cause women to die due to breast cancer. Thus we did some analysis manually i.e. on lymph nodes status, and SPSS software helped to analyze the mentioned data. This study found out that there is an application difference between Cox and Logistic regression models which is Cox regression model is used if one wishes to analyze data which also include the follow-up time whereas Logistic regression model analyzes data without follow-up-time. Also, they have measurements of association which is different: hazard ratio and odds ratio for Cox and logistic regression models respectively. A similarity between the two models is that they are both applicable in the prediction of the upshot of a categorical variable i.e. a variable that can accommodate only a restricted number of categories. In conclusion, Cox regression model differs from logistic regression by assessing a rate instead of proportion. The two models can be applied in many other researches since they are suitable methods for analyzing data but the more recommended is the Cox, regression model.

Keywords: logistic regression model, Cox regression model, survival analysis, hazard ratio

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