Search results for: variable magnetization
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2302

Search results for: variable magnetization

1822 Globally Convergent Sequential Linear Programming for Multi-Material Topology Optimization Using Ordered Solid Isotropic Material with Penalization Interpolation

Authors: Darwin Castillo Huamaní, Francisco A. M. Gomes

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The aim of the multi-material topology optimization (MTO) is to obtain the optimal topology of structures composed by many materials, according to a given set of constraints and cost criteria. In this work, we seek the optimal distribution of materials in a domain, such that the flexibility of the structure is minimized, under certain boundary conditions and the intervention of external forces. In the case we have only one material, each point of the discretized domain is represented by two values from a function, where the value of the function is 1 if the element belongs to the structure or 0 if the element is empty. A common way to avoid the high computational cost of solving integer variable optimization problems is to adopt the Solid Isotropic Material with Penalization (SIMP) method. This method relies on the continuous interpolation function, power function, where the base variable represents a pseudo density at each point of domain. For proper exponent values, the SIMP method reduces intermediate densities, since values other than 0 or 1 usually does not have a physical meaning for the problem. Several extension of the SIMP method were proposed for the multi-material case. The one that we explore here is the ordered SIMP method, that has the advantage of not being based on the addition of variables to represent material selection, so the computational cost is independent of the number of materials considered. Although the number of variables is not increased by this algorithm, the optimization subproblems that are generated at each iteration cannot be solved by methods that rely on second derivatives, due to the cost of calculating the second derivatives. To overcome this, we apply a globally convergent version of the sequential linear programming method, which solves a linear approximation sequence of optimization problems.

Keywords: globally convergence, multi-material design ordered simp, sequential linear programming, topology optimization

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1821 The Effectiveness of Teaching Emotional Intelligence on Reducing Marital Conflicts and Marital Adjustment in Married Students of Tehran University

Authors: Elham Jafari

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The aim of this study was to evaluate the effectiveness of emotional intelligence training on reducing marital conflict and marital adjustment in married students of the University of Tehran. This research is an applied type in terms of purpose and a semi-experimental design of pre-test-post-test type with the control group and with follow-up test in terms of the data collection method. The statistical population of the present study consisted of all married students of the University of Tehran. In this study, 30 married students of the University of Tehran were selected by convenience sampling method as a sample that 15 people in the experimental group and 15 people in the control group were randomly selected. The method of data collection in this research was field and library. The data collection tool in the field section was two questionnaires of marital conflict and marital adjustment. To analyze the collected data, first at the descriptive level, using statistical indicators, the demographic characteristics of the sample were described by SPSS software. In inferential statistics, the statistical method used was the test of analysis of covariance. The results showed that the effect of the independent variable of emotional intelligence on the reduction of marital conflicts is statistically significant. And it can be inferred that emotional intelligence training has reduced the marital conflicts of married students of the University of Tehran in the experimental group compared to the control group. Also, the effect of the independent variable of emotional intelligence on marital adjustment was statistically significant. It can be inferred that emotional intelligence training has adjusted the marital adjustment of married students of the University of Tehran in the experimental group compared to the control group.

Keywords: emotional intelligence, marital conflicts, marital compatibility, married students

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1820 Collaborative Planning and Forecasting

Authors: Neha Asthana, Vishal Krishna Prasad

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Collaborative planning and forecasting are the innovative and systematic approaches towards productive integration and assimilation of data synergized into information. The changing and variable market dynamics have persuaded global business chains to incorporate collaborative planning and forecasting as an imperative tool. Thus, it is essential for the supply chains to constantly improvise, update its nature, and mould as per changing global environment.

Keywords: information transfer, forecasting, optimization, supply chain management

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1819 Challenges in Achieving Profitability for MRO Companies in the Aviation Industry: An Analytical Approach

Authors: Nur Sahver Uslu, Ali̇ Hakan Büyüklü

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Maintenance, Repair, and Overhaul (MRO) costs are significant in the aviation industry. On the other hand, companies that provide MRO services to the aviation industry but are not dominant in the sector, need to determine the right strategies for sustainable profitability in a competitive environment. This study examined the operational real data of a small medium enterprise (SME) MRO company where analytical methods are not widely applied. The company's customers were divided into two categories: airline companies and non-airline companies, and the variables that best explained profitability were analyzed with Logistic Regression for each category and the results were compared. First, data reduction was applied to the transformed variables that went through the data cleaning and preparation stages, and the variables to be included in the model were decided. The misclassification rates for the logistic regression results concerning both customer categories are similar, indicating consistent model performance across different segments. Less profit margin is obtained from airline customers, which can be explained by the variables part description, time to quotation (TTQ), turnaround time (TAT), manager, part cost, and labour cost. The higher profit margin obtained from non-airline customers is explained only by the variables part description, part cost, and labour cost. Based on the two models, it can be stated that it is significantly more challenging for the MRO company, which is the subject of our study, to achieve profitability from Airline customers. While operational processes and organizational structure also affect the profit from airline customers, only the type of parts and costs determine the profit for non-airlines.

Keywords: aircraft, aircraft components, aviation, data analytics, data science, gini index, maintenance, repair, and overhaul, MRO, logistic regression, profit, variable clustering, variable reduction

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1818 The Mechanisms of Peer-Effects in Education: A Frame-Factor Analysis of Instruction

Authors: Pontus Backstrom

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In the educational literature on peer effects, attention has been brought to the fact that the mechanisms creating peer effects are still to a large extent hidden in obscurity. The hypothesis in this study is that the Frame Factor Theory can be used to explain these mechanisms. At heart of the theory is the concept of “time needed” for students to learn a certain curricula unit. The relations between class-aggregated time needed and the actual time available, steers and hinders the actions possible for the teacher. Further, the theory predicts that the timing and pacing of the teachers’ instruction is governed by a “criterion steering group” (CSG), namely the pupils in the 10th-25th percentile of the aptitude distribution in class. The class composition hereby set the possibilities and limitations for instruction, creating peer effects on individual outcomes. To test if the theory can be applied to the issue of peer effects, the study employs multilevel structural equation modelling (M-SEM) on Swedish TIMSS 2015-data (Trends in International Mathematics and Science Study; students N=4090, teachers N=200). Using confirmatory factor analysis (CFA) in the SEM-framework in MPLUS, latent variables are specified according to the theory, such as “limitations of instruction” from TIMSS survey items. The results indicate a good model fit to data of the measurement model. Research is still in progress, but preliminary results from initial M-SEM-models verify a strong relation between the mean level of the CSG and the latent variable of limitations on instruction, a variable which in turn have a great impact on individual students’ test results. Further analysis is required, but so far the analysis indicates a confirmation of the predictions derived from the frame factor theory and reveals that one of the important mechanisms creating peer effects in student outcomes is the effect the class composition has upon the teachers’ instruction in class.

Keywords: compositional effects, frame factor theory, peer effects, structural equation modelling

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1817 An Exploratory Research on Awareness towards Human Rights among Public Representatives of Bihar, India

Authors: Saba Farheen, Uday Shankar

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Background- Attaining equality among all humans and eliminating all forms of discrimination against them are fundamental human rights. These rights are based on the belief that all human beings are born free with equal dignity, esteem, and honour. In India, more than 30 percent politicians are having criminal background. They are also illiterate, which obstacle them in governing the system. They do not know the basic human rights. Because of this, they cannot decide what to do for the sake of the nation. Bihar is the third largest populated state of India and is characterized by corrupt politicians and poor literacy rate. If the politicians can aware about the human rights, then they will show positive attitude towards these. Aim- The main goal of the present research was to study the subjects’ knowledge or awareness towards their human rights. It was an attempt to identify social-psychological conditions that inhibit or facilitate awareness among public representatives towards their human rights in the special context of Bihar, India. Thus the main variable awareness towards human rights has been treated as the main dependent variable. The other two variables-socio economic status and Educational status, have been treated as independent variables. Method- The subjects were 400 public representatives in the age group of 35 to 50 years. They were from High socio economic status (N=150), Middle socio economic status (N=150), and Low socio economic status (N=100). The subjects were either educated (N=200) or Uneducated (N=200). The subjects were selected randomly from the different districts of Bihar, India. “Human Rights Awareness Scale” by Dr. Iftekhar Hossain, Dr. Saba Farheen, and Dr. Uday Shankar was applied in this study. Results- Results have shown that the public representatives have very low level of awareness towards the human rights. Also, the subjects from Middle SES have highest awareness in comparison with subjects of High and Low SES. Uneducated public representatives have less awareness than the educated one about human rights. Conclusion- Conclusively, it can be stated that human rights awareness among the public representatives of India is very low, and it is being affected by their Socio economic status and literacy level.

Keywords: human rights, awareness, public representatives, bihar, India

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1816 Ideas About Varroa Destructor Reproduction in the Honey Bees (Hymenoptera: Apidae)

Authors: William Ramirez-Benavides

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The mite Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae), is an exclusive hematophagous parasite of the Apis honey bees (Apidae: Hymenoptera). The early phoretic female mites have multiple small inactivated oocytes. Consequently, for the initial growth and vitellogenesis of the oocytes, the mother mite must feed on the hemolymph of the host, as a unique food source, by taking intermittently variable number of blood meals: 1. During the phoretic phase, to initiate vitellogenesis of the terminal oocyte, 2. From a freshly capped bee cell with a bee larva, up to the apolysis stage, to complete vitellogenesis and embryogenesis of the terminal oocyte, and 3. From all pupal stages, up to the imago stage, to induce oogenesis and vitellogenesis of the would-be nonembryonic female eggs. Additionally, oogenesis and vitellogenesis expressions in Varroa destructor and other Varroidae varies according to environmental conditions, e.g., chemical attractions produced by the adult bee and larvae, race of bees, sex of the larva, developmental period of the bee larva, food quality and quantity, and superparasitism (several cofoundressess). Also, the feeding stimuli obtained from the host hemolymph, indirectly regulate the reproductive physiology of the mite, by inducing different vitellogenin expressions, the production of a male egg first in the sequence followed by vitellogenesis of the would-be female eggs during the pupal stages. Furthermore, the different uptakes of hemolymph from the host, also indirectly induce the production of the male egg first in the sequence, local mate competition (LMC) and variable adaptive female sex ratios in the broods, especially when superparasitism occurs. Consequently, reproduction in Varroa destructor, and probably in other Varroidae, depends exclusively on feeding in the hemolymph of the bee host, even during the phoretic phase, the prepupal stages and during the pupal stages; and that, the feeding factors are common syndromes in other Varroidae.

Keywords: oogenesis, sex determination, varroa destructor, vitellogenesis

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1815 Data Transformations in Data Envelopment Analysis

Authors: Mansour Mohammadpour

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Data transformation refers to the modification of any point in a data set by a mathematical function. When applying transformations, the measurement scale of the data is modified. Data transformations are commonly employed to turn data into the appropriate form, which can serve various functions in the quantitative analysis of the data. This study addresses the investigation of the use of data transformations in Data Envelopment Analysis (DEA). Although data transformations are important options for analysis, they do fundamentally alter the nature of the variable, making the interpretation of the results somewhat more complex.

Keywords: data transformation, data envelopment analysis, undesirable data, negative data

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1814 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

Abstract:

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

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1813 Exploring Relationship of National Talent Retention and National Value Proposition

Authors: Dzul Fahmi Md. Nordin, Rosmini Omar

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This conceptual paper aims to explore the concept of National Talent Retention for a nation by extending the works on Talent Retention in organizations to the scope of nations. The objective of this paper is to explore the relationship of National Talent Retention as the dependent variable with the three explored value propositions namely Firm Value Proposition, Higher Education and Training Value Proposition and National Attractiveness Value Proposition as the independent variables. Life Satisfaction is introduced in this study as a moderating variable to explore possibilities of Life Satisfaction as a mediator for the relationship between National Value Proposition and National Talent Retention. Theories such as Migration, Value Propositions, Life Satisfaction, Human Resource Management and Resource Based View are referred to in order to understand and explore the concept of National Talent Retention. Malaysia is chosen as the background of this study since Malaysia represents a developing nation with progressive economic, education and national policy which presents an interesting background for this exploratory paper. Surprisingly, Malaysia is still facing the phenomenon of Brain Drain which if not handled properly will hinder its Vision 2020 to progress a fully developed nation by year 2020. Mixed methodology analysis is proposed in this paper to include both qualitative face-to-face interview as well as quantitative survey questionnaire to study on the value proposition factors explored. Target respondents are strictly confined to Malaysia’s local high skilled talents either residing in Malaysia or migrated abroad since this paper is mainly interested to study on the concept of National Talent Retention and how successful Malaysia is projecting its value propositions from the perception of high skilled talent Malaysians. It is hoped that this paper could contribute towards understanding National Talent Retention concept where, the model could be replicated to identify influential factors specific to other nations.

Keywords: national talent retention, national value proposition, life satisfaction, high skilled talents

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1812 Attitude to Cultural Diversity and Inclusive Pedagogical Practices in the Classroom: A Correlational Study

Authors: Laura M. Espinoza, Karen A. Hernández, Diana B. Ledezma

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Currently, in Chile, migratory movements are generated, where the country receives constantly people from Latin America such as Colombia, Peru, Venezuela, Haiti, among others. This phenomenon has reached the schools of Chile, where immigrant children and adolescents are educated in a context of cultural diversity. However, education professionals face this recent phenomenon without prior preparation to carry out their pedagogical practices in the classroom. On the other hand, research on how to understand and guide the processes of cultural diversity especially within the school is even scarce and recent in Latin America and specifically in Chile. The general purpose of the study is to analyze the relationships between teaching efforts towards multiculturalism and inclusive pedagogical practices in the schools of the city of La Serena and Coquimbo, in Chile. The study refers to a quantitative approach, with a correlational design. The selection of the participants was not intentional probabilistic. It comprises 88 teachers of preschool, primary, secondary and special education, who work in two schools with similar characteristics. For the collection of information on the independent variable, the attitude scale towards Immigration and the attitude scale towards Multiculturalism in the school are applied. To obtain information on the independent variable, the guide for the evaluation of inclusive practices in the classroom is applied. Both instruments have statistical validation. A Spearman correlation analysis was made to achieve the objective of the study. Among the main findings, we will find the relationships between the positive perceptions of multiculturalism at school and inclusive practices such as the physical conditions of the classroom, planning, methodology, use of time and evaluation. These findings are relevant to the teaching and learning processes of students in Chilean classrooms and contribute to literature for the understanding of educational processes in contexts of cultural diversity.

Keywords: cultural diversity, immigration, inclusive pedagogical practices, multiculturalism

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1811 Numerical Investigation of Gas Leakage in RCSW-Soil Combinations

Authors: Mahmoud Y. M. Ahmed, Ahmed Konsowa, Mostafa Sami, Ayman Mosallam

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Fukushima nuclear accident (Japan 2011) has drawn attention to the issue of gas leakage from hazardous facilities through building boundaries. The rapidly increasing investments in nuclear stations have made the ability to predict, and prevent, gas leakage a rather crucial issue both environmentally and economically. Leakage monitoring for underground facilities is rather complicated due to the combination of Reinforced Concrete Shear Wall (RCSW) and soil. In the framework of a recent research conducted by the authors, the gas insulation capabilities of RCSW-soil combination have been investigated via a lab-scale experimental work. Despite their accuracy, experimental investigations are expensive, time-consuming, hazardous, and lack for flexibility. Numerically simulating the gas leakage as a fluid flow problem based on Computational Fluid Dynamics (CFD) modeling approach can provide a potential alternative. This novel implementation of CFD approach is the topic of the present paper. The paper discusses the aspects of modeling the gas flow through porous media that resemble the RCSW both isolated and combined with the normal soil. A commercial CFD package is utilized in simulating this fluid flow problem. A fixed RCSW layer thickness is proposed, air is taken as the leaking gas, whereas the soil layer is represented as clean sand with variable properties. The variable sand properties include sand layer thickness, fine fraction ratio, and moisture content. The CFD simulation results almost demonstrate what has been found experimentally. A soil layer attached next to a cracked reinforced concrete section plays a significant role in reducing the gas leakage from that cracked section. This role is found to be strongly dependent on the soil specifications.

Keywords: RCSW, gas leakage, Pressure Decay Method, hazardous underground facilities, CFD

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1810 Magnetic Chloromethylated Polymer Nanocomposite for Selective Pollutant Removal

Authors: Fabio T. Costa, Sergio E. Moya, Marcelo H. Sousa

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Nanocomposites designed by embedding magnetic nanoparticles into a polymeric matrix stand out as ideal magnetic-hybrid and magneto-responsive materials as sorbents for removal of pollutants in environmental applications. Covalent coupling is often desired for the immobilization of species on these nanocomposites, in order to keep them permanently bounded, not desorbing or leaching over time. Moreover, unwanted adsorbates can be separated by successive washes/magnetic separations, and it is also possible to recover the adsorbate covalently bound to the nanocomposite surface through detaching/cleavage protocols. Thus, in this work, we describe the preparation and characterization of highly-magnetizable chloromethylated polystyrene-based nanocomposite beads for selective covalent coupling in environmental applications. For synthesis optimization, acid resistant core-shelled maghemite (γ-Fe₂O₃) nanoparticles were coated with oleate molecules and directly incorporated into the organic medium during a suspension polymerization process. Moreover, the cross-linking agent ethylene glycol dimethacrylate (EGDMA) was utilized for co-polymerization with the 4-vinyl benzyl chloride (VBC) to increase the resistance of microbeads against leaching. After characterizing samples with XRD, ICP-OES, TGA, optical, SEM and TEM microscopes, a magnetic composite consisting of ~500 nm-sized cross-linked polymeric microspheres embedding ~8 nm γ-Fe₂O₃ nanoparticles was verified. This nanocomposite showed large room temperature magnetization (~24 emu/g) due to the high content in maghemite (~45 wt%) and resistance against leaching even in acidic media. Moreover, the presence of superficial chloromethyl groups, probed by FTIR and XPS spectroscopies and confirmed by an amination test can selectively adsorb molecules through the covalent coupling and be used in molecular separations as shown for the selective removal of 4-aminobenzoic acid from a mixture with benzoic acid.

Keywords: nanocomposite, magnetic nanoparticle, covalent separation, pollutant removal

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1809 On Bianchi Type Cosmological Models in Lyra’s Geometry

Authors: R. K. Dubey

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Bianchi type cosmological models have been studied on the basis of Lyra’s geometry. Exact solution has been obtained by considering a time dependent displacement field for constant deceleration parameter and varying cosmological term of the universe. The physical behavior of the different models has been examined for different cases.

Keywords: Bianchi type-I cosmological model, variable gravitational coupling, cosmological constant term, Lyra's model

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1808 Tailoring and Characterization of Lithium Manganese Ferrite- Polypyrrole Nanocomposite (LixMnxFe₂O₄-PPY) to Evaluate Their Performance as an Energy Storage Device

Authors: Muhammad Waheed Mushtaq, Shahid bashir, Atta Ur Rehman

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In the past decade, the growing demand for capital and the increased utilization of supercapacitors reflect advancements in energy-producing systems and energy storage devices. Metal oxides and ferrites have emerged as promising candidates for supercapacitors and batteries. In our current study, we synthesized Lithium manganese nanoferrite, denoted as LixMnxFe₂O₄, using the hydrothermal technique. Subsequently, we treated it with sodium dodecyl benzene sulphonate (SDBS) surfactant to create nanocomposites of Lithium manganese nano ferrite (LMFe) with poly pyrrole (LixMnxFe₂O₄-PPY). We employed Powder X-ray diffraction (XRD) to confirm the crystalline nature and spinel phase structure of LMFe nanoparticles, which exhibited a single-phase crystal structure, indicating sample purity. To assess the surface topography, morphology, and grain size of both synthesized LixMnxFe₂O₄ and LixMnxFe₂O₄-PPY, we used atomic force microscopy and scanning electron microscopy (SEM). The average particle size of pure ferrite was found to be 54 nm, while that of its nanocomposite was 71 nm. Energy dispersive X-ray (EDX) analysis confirmed the presence of all required elements, including Li, Mn, Fe, and O, in the appropriate proportions. Saturation magnetization (32.69 emu), remanence (Mr), and coercive force (Hc) were measured using a Vibrating Sample Magnetometer (VSM). To assess the electrochemical performance of the material, we conducted Cyclic Voltammetry (CV) measurements for both pure LMFe and LMFe-PPY. The CV results for LMFe-PPY demonstrated that specific capacitance decreased with increasing scan rate while the area of the current-voltage loop increased. These findings are promising for the development of supercapacitors and lithium-ion batteries (LIBs).

Keywords: lithium manganese ferrite, poly pyrrole, nanocomposites, cyclic voltammetry, cathode

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1807 Constructing the Joint Mean-Variance Regions for Univariate and Bivariate Normal Distributions: Approach Based on the Measure of Cumulative Distribution Functions

Authors: Valerii Dashuk

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The usage of the confidence intervals in economics and econometrics is widespread. To be able to investigate a random variable more thoroughly, joint tests are applied. One of such examples is joint mean-variance test. A new approach for testing such hypotheses and constructing confidence sets is introduced. Exploring both the value of the random variable and its deviation with the help of this technique allows checking simultaneously the shift and the probability of that shift (i.e., portfolio risks). Another application is based on the normal distribution, which is fully defined by mean and variance, therefore could be tested using the introduced approach. This method is based on the difference of probability density functions. The starting point is two sets of normal distribution parameters that should be compared (whether they may be considered as identical with given significance level). Then the absolute difference in probabilities at each 'point' of the domain of these distributions is calculated. This measure is transformed to a function of cumulative distribution functions and compared to the critical values. Critical values table was designed from the simulations. The approach was compared with the other techniques for the univariate case. It differs qualitatively and quantitatively in easiness of implementation, computation speed, accuracy of the critical region (theoretical vs. real significance level). Stable results when working with outliers and non-normal distributions, as well as scaling possibilities, are also strong sides of the method. The main advantage of this approach is the possibility to extend it to infinite-dimension case, which was not possible in the most of the previous works. At the moment expansion to 2-dimensional state is done and it allows to test jointly up to 5 parameters. Therefore the derived technique is equivalent to classic tests in standard situations but gives more efficient alternatives in nonstandard problems and on big amounts of data.

Keywords: confidence set, cumulative distribution function, hypotheses testing, normal distribution, probability density function

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1806 Optimum Design of Heat Exchanger in Diesel Engine Cold EGR for Pollutants Reduction

Authors: Nasser Ghassembaglou, Armin Rahmatfam, Faramarz Ranjbar

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Using of cold EGR method with variable venturi and turbocharger has a very significant affection on the reduction of NOX and grime simultaneously. EGR cooler is one of the most important parts in the cold EGR circuit. In this paper optimum design of cooler for working in different percents of EGR and for determining of optimum temperature of exhausted gases, growth of efficiency, reduction of weight, reduction of dimension and expenditures, and reduction of sediment and optimum performance by using gas oil which has significant amounts of brimstone are investigated and optimized.

Keywords: cold EGR, NOX, cooler, gas oil

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1805 Relationship between Static Balance and Body Characteristics in the Elderly

Authors: J. W. Kim, Y. R. Kwon, Y. J. Ho, H. M. Jeon, G. M. Eom

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The aim of this study was to investigate the association of anthropometry with static balance in the elderly and their possible gender difference. Forty six subjects (23 men and 23 women) participated in this study. COP (Center of Pressure) was measured on a force-platform during quiet feet-together standing. As outcome measures, mean distance were derived from the COP. Weight was significantly correlated with postural variable only in the elderly men. This result suggests that the gender should be considered when normalizing postural variables.

Keywords: body characteristics, postural balance, elderly, gender difference

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1804 Relationship between Glycated Hemoglobin in Adolescents with Type 1 Diabetes Mellitus and Parental Anxiety and Depression

Authors: Evija Silina, Maris Taube, Maksims Zolovs

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Background: Type 1 diabetes mellitus (T1D) is the most common chronic endocrine pathology in children. The management of type 1 diabetes requires a strong diet, physical activity, lifelong insulin therapy, and proper self-monitoring of blood glucose and is usually complicated and, therefore, may result in a variety of psychosocial problems for children, adolescents, and their families. Metabolic control of the disease is determined by glycated haemoglobin (HbA1c), the main criterion for diabetes compensation. A correlation was observed between anxiety and depression levels and glycaemic control in many previous studies. It is assumed that anxiety and depression symptoms negatively affect glycaemic control. Parental psychological distress was associated with higher child self-report of stress and depressive symptoms, and it had negative effects on diabetes management. Objective: The main objective of this paper is to evaluate the relationship between parental mental health conditions (depression and anxiety) and metabolic control of their adolescents with T1DM. Methods: This cross-sectional study recruited adolescents with T1D (N=251) and their parents (N=251). The respondents completed questionnaires. The 7-item Generalized Anxiety Disorder (GAD-7) scale measured anxiety level; The Patient Health Questionnaire – 9 (PHQ-9) measured depressive symptoms. Glycaemic control of patients was assessed using the last glycated haemoglobin (HbA1c) values. GLM mediation analysis was performed to determine the potential mediating effect of the parent’s mental health conditions (depression and anxiety) on the relationship between the mental health conditions (depression and anxiety) of a child on the level of glycated hemoglobin (HbA1c). To test the significance of the mediated effect (ME) for non-normally distributed data, bootstrapping procedures (10,000 bootstrapped samples) were used. Results: 502 respondents were eligible for screening to detect anxiety and depression symptoms. Mediation analysis was performed to assess the mediating role of parent GAD-7 on the linkage between a dependent variable (HbA1c) and independent variables (child GAD-7 un child PHQ-9). The results revealed that the total effect of child GAD-7 (B = 0.479, z = 4.30, p < 0.001) on HbA1c was significant but the total effect of child PHQ-9 (B = 0.166, z = 1.49, p = 0.135) was not significant. With the inclusion of the mediating variable (parent GAD-7), the impact of child GAD-7 on HbA1c was found insignificant (B = 0.113, z=0.98, p = 0.326), the impact of child PHQ-9 on HbA1c was found also insignificant (B = 0.068, z=0.74, p = 0.458). The indirect effect of child GAD-7 on HbA1c through parent GAD-7 was found significant (B = 0.366, z = 4.31, p < 0.001) and the indirect effect of child PHQ-9 on HbA1c through parent GAD-7 was found also significant (B = 0.098, z = 2.56, p = 0.010). This indicates that the relationship between a dependent variable (HbA1c) and independent variables (child GAD-7 un child PHQ-9) is fully mediated by parent GAD-7. Conclusion: The main result suggests that glycated haemoglobin in adolescents with Type 1 diabetes is related to adolescents’ mental health via parents’ anxiety. It means that parents’ anxiety plays a more significant role in the level of glycated haemoglobin in adolescents than depression and anxiety in the adolescent.

Keywords: type 1 diabetes, adolescents, parental diabetes-specific mental health conditions, glycated haemoglobin, anxiety, depression

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1803 Disentangling the Relationship between Sustainable Consumption and Psychological Well-Being

Authors: Isabel Carrero, Raquel Redondo, Carmen Valor

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An unclosed issue in sustainable consumption (SC) literature is the relationship between SC and well-being. This paper seeks to address three limitations in past research. First, well-being has been measured as a single-faceted construct. However, other authors have defended the need to broaden the well-being construct since it goes beyond the emotional experiences and life satisfaction. By examining the relationship between SC and the multifaceted construct of psychological well-being, past contradictory results may be reconciled. To illustrate, past studies have shown that sustainable consumers experience negative emotions when they become aware of the harm that human beings inflict on the planet but they realize they have limited power to solving the problem or when they find limited alternatives or useful information to make sustainable decisions. Thus, these experiences may negatively affect the dimension of well-being 'environmental mastery'. However, as past studies have demonstrated that sustainable consumers feel meaningful, their assessment of the dimension 'purpose in life' would be positive. Thus, we need to understand how SC impinge on the different facets of psychological well-being, in order to better understand the relationship between SC and well-being. Another limitation of past research is that most studies failed to distinguish among different pro-environmental actions under SC (i.e., boycotting, buycotting) among others. For instance, activists have been found to experience higher levels of well-being and sense of meaning than less committed sustainable consumers but also burnt-out and social rejection, which should affect negatively the dimension of 'positive relations'. Finally, the influence of gender has been overlooked in the literature of SC and well-being when it has been identified consistently as a moderator variable in SC. Therefore, this study aims to (1) investigate the effect of SC on the six facets of psychological well-being, (2) distinguish between conventional SC behaviors vs. activism to examine whether these behaviors influence psychological well-being differently (3) and test gender as a moderator variable. It does so by surveying 861 individuals. This paper contributes to existing literature by showing that the relationship between well-being and SC is more intricate than it has been presented in previous literature, as it depends on the facet, the type of behavior carried out and gender.

Keywords: activism, gender, psychological well-being, structural equation modelling, sustainable consumption

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1802 Contribution to Improving the DFIG Control Using a Multi-Level Inverter

Authors: Imane El Karaoui, Mohammed Maaroufi, Hamid Chaikhy

Abstract:

Doubly Fed Induction Generator (DFIG) is one of the most reliable wind generator. Major problem in wind power generation is to generate Sinusoidal signal with very low THD on variable speed caused by inverter two levels used. This paper presents a multi-level inverter whose objective is to reduce the THD and the dimensions of the output filter. This work proposes a three-level NPC-type inverter, the results simulation are presented demonstrating the efficiency of the proposed inverter.

Keywords: DFIG, multilevel inverter, NPC inverter, THD, induction machine

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1801 Corporate Social Responsibility (CSR) and Energy Efficiency: Empirical Evidence from the Manufacturing Sector of India

Authors: Baikunthanath Sahoo, Santosh Kumar Sahu, Krishna Malakar

Abstract:

With the essence of global environmental sustainability and green business management, the wind of business research moved towards Corporate Social Responsibility. In addition to international and national treaties, businesses have also started realising environmental protection and energy efficiency through CSR as part of business strategy in response to climate change. Considering the ambitious emission reduction target and rapid economic development of India, this study is an attempt to explore the effect of CSR on the energy efficiency management of manufacturing firms in India. By using firm-level data, the panel fixed effect model shows that the CSR dummy variable is negatively influencing the energy intensity or technically, they are energy efficient. The result demonstrates that in the presence of CSR, all the production economic variables are significant. The result also shows that doing environmental expenditure does not improve energy efficiency might be because very few firms are motivated to do such expenditure and also not common to all sectors. The interactive effect model result conforms that without considering CSR dummy as an intervening variable only Manufacturers of Chemical and Chemical products, Manufacturers of Pharmaceutical, medical chemical, and botanical products firms energy intensity low but after considering CSR in their business practices all six sub-sector firms become energy efficient. The empirical result also validate that firms are continuously engaged in CSR activities they are highly energy efficient. It is an important motivational factor for firms to become economically and environmentally sustainable in the corporate world. This analysis would help business practitioners to know how to manage today’s profitability and tomorrow’s sustainability to achieve a comparative advantage in the emerging market economy. The paper concludes that reducing energy consumption as part of their social responsibility to care for the environment, will need collaborative efforts of business society and policy bodies.

Keywords: CSR, Energy Efficiency, Indian manufacturing Sector, Business strategy

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1800 Association of the Time in Targeted Blood Glucose Range of 3.9–10 Mmol/L with the Mortality of Critically Ill Patients with or without Diabetes

Authors: Guo Yu, Haoming Ma, Peiru Zhou

Abstract:

BACKGROUND: In addition to hyperglycemia, hypoglycemia, and glycemic variability, a decrease in the time in the targeted blood glucose range (TIR) may be associated with an increased risk of death for critically ill patients. However, the relationship between the TIR and mortality may be influenced by the presence of diabetes and glycemic variability. METHODS: A total of 998 diabetic and non-diabetic patients with severe diseases in the ICU were selected for this retrospective analysis. The TIR is defined as the percentage of time spent in the target blood glucose range of 3.9–10.0 mmol/L within 24 hours. The relationship between TIR and in-hospital in diabetic and non-diabetic patients was analyzed. The effect of glycemic variability was also analyzed. RESULTS: The binary logistic regression model showed that there was a significant association between the TIR as a continuous variable and the in-hospital death of severely ill non-diabetic patients (OR=0.991, P=0.015). As a classification variable, TIR≥70% was significantly associated with in-hospital death (OR=0.581, P=0.003). Specifically, TIR≥70% was a protective factor for the in-hospital death of severely ill non-diabetic patients. The TIR of severely ill diabetic patients was not significantly associated with in-hospital death; however, glycemic variability was significantly and independently associated with in-hospital death (OR=1.042, P=0.027). Binary logistic regression analysis of comprehensive indices showed that for non-diabetic patients, the C3 index (low TIR & high CV) was a risk factor for increased mortality (OR=1.642, P<0.001). In addition, for diabetic patients, the C3 index was an independent risk factor for death (OR=1.994, P=0.008), and the C4 index (low TIR & low CV) was independently associated with increased survival. CONCLUSIONS: The TIR of non-diabetic patients during ICU hospitalization was associated with in-hospital death even after adjusting for disease severity and glycemic variability. There was no significant association between the TIR and mortality of diabetic patients. However, for both diabetic and non-diabetic critically ill patients, the combined effect of high TIR and low CV was significantly associated with ICU mortality. Diabetic patients seem to have higher blood glucose fluctuations and can tolerate a large TIR range. Both diabetic and non-diabetic critically ill patients should maintain blood glucose levels within the target range to reduce mortality.

Keywords: severe disease, diabetes, blood glucose control, time in targeted blood glucose range, glycemic variability, mortality

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1799 Distance and Coverage: An Assessment of Location-Allocation Models for Fire Stations in Kuwait City, Kuwait

Authors: Saad M. Algharib

Abstract:

The major concern of planners when placing fire stations is finding their optimal locations such that the fire companies can reach fire locations within reasonable response time or distance. Planners are also concerned with the numbers of fire stations that are needed to cover all service areas and the fires, as demands, with standard response time or distance. One of the tools for such analysis is location-allocation models. Location-allocation models enable planners to determine the optimal locations of facilities in an area in order to serve regional demands in the most efficient way. The purpose of this study is to examine the geographic distribution of the existing fire stations in Kuwait City. This study utilized location-allocation models within the Geographic Information System (GIS) environment and a number of statistical functions to assess the current locations of fire stations in Kuwait City. Further, this study investigated how well all service areas are covered and how many and where additional fire stations are needed. Four different location-allocation models were compared to find which models cover more demands than the others, given the same number of fire stations. This study tests many ways to combine variables instead of using one variable at a time when applying these models in order to create a new measurement that influences the optimal locations for locating fire stations. This study also tests how location-allocation models are sensitive to different levels of spatial dependency. The results indicate that there are some districts in Kuwait City that are not covered by the existing fire stations. These uncovered districts are clustered together. This study also identifies where to locate the new fire stations. This study provides users of these models a new variable that can assist them to select the best locations for fire stations. The results include information about how the location-allocation models behave in response to different levels of spatial dependency of demands. The results show that these models perform better with clustered demands. From the additional analysis carried out in this study, it can be concluded that these models applied differently at different spatial patterns.

Keywords: geographic information science, GIS, location-allocation models, geography

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1798 The Impact of Environmental Corporate Social Responsibility (ECSR) and the Perceived Moral Intensity on the Intention of Ethical Investment

Authors: Chiung-Yao Huang, Yu-Cheng Lin, Chiung-Hui Chen

Abstract:

This study seeks to examine perceived environmental corporate social responsibility (ECSR) with a focus on negative environmental questions, related to intention of ethical investment intention after a environmental failure recovery. An empirical test was employed to test the hypotheses. We manipulated the information on negative ECSR activities of a hypothetical firm in a experimental design with a failure recovery treatment. The company’s negative ECSR recovery was depicted in a positive perspective (depicting a follow-up strong social action), whereas in the negative ECSR treatment it was described in a negative perspective (depicting a follow-up non social action). In both treatments, information about other key characteristics of the focal company were kept constant. Investors’ intentions to invest in the company’s stock were evaluated by multi-item scales. Results indicate that positive ECSR recovery information about a firm enhances investors’ intentions to invest in the company’s stock. In addition, perceived moral intensity has a significant impact on the intention of ethical investment and that perceived moral intensity also serves as a key moderating variable in the relationship between negative ECSR and the intention of ethical investment. Finally, theoretical and managerial implications of the findings are discussed. Practical implications: The results suggest that managers may need to be aware of perceived moral intensity as a key variable in restoring the intention of ethical investment. The results further suggest that perceived moral intensity has a direct, and it also has an moderating influence between ECSR and the intention of ethical investment. Originality/value: In an attempt to deepen the understanding of how investors perceptions of firm environmental CSR are connected with other investor‐related outcomes through ECSR recovery, the present research proposes a comprehensive model which encompasses ECSR and other key relationship constructs after a ECSR failure and recovery.

Keywords: ethical investment, Environmental Corporate Social Responsibility(ECSR), ECSR recovery, moral intensity

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1797 Italian Colonial Strategy in Libya and the Conflict of Super Powers

Authors: Mohamed Basheer Abdul Atti Hassan

Abstract:

This research paper will follow the main outlines of the Italian colonization in Libya in a historical geopolitical approach; before we reach the contemporary map. In this study, we are also concerned with following the chain's links, not as drama in time, but as a strategy in place, so that it draws to us a map of power and the distribution of political formations throughout this period within and around Libya. From the sum of these variable distributions and successive balances, we can come up with the basic principles that determined the Italian history in Libya and formed its political entity, which is a compass of guidance and an indication of the future.

Keywords: conflict, Mediterranean, colonization, political history

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1796 Insecurity and Insurgency on Economic Development of Nigeria

Authors: Uche Lucy Onyekwelu, Uche B. Ugwuanyi

Abstract:

Suffice to say that socio-economic disruptions of any form is likely to affect the wellbeing of the citizenry. The upsurge of social disequilibrium caused by the incessant disruptive tendencies exhibited by youths and some others in Nigeria are not helping matters. In Nigeria the social unrest has caused different forms of draw backs in Socio Economic Development. This study has empirically evaluated the impact of insecurity and insurgency on the Economic Development of Nigeria. The paper noted that the different forms of insecurity in Nigeria are namely: Insurgency and Banditry as witnessed in Northern Nigeria; Militancy: Niger Delta area and self-determination groups pursuing various forms of agenda such as Sit –at- Home Syndrome in the South Eastern Nigeria and other secessionist movements. All these have in one way or the other hampered Economic development in Nigeria. Data for this study were collected through primary and secondary sources using questionnaire and some existing documentations. Cost of investment in different aspects of security outfits in Nigeria represents the independent variable while the differentials in the Gross Domestic Product(GDP) and Human Development Index(HDI) are the measures of the dependent variable. Descriptive statistics and Simple Linear Regression analytical tool were employed in the data analysis. The result revealed that Insurgency/Insecurity negatively affect the economic development of the different parts of Nigeria. Following the findings, a model to analyse the effect of insecurity and insurgency was developed, named INSECUREDEVNIG. It implies that the economic development of Nigeria will continue to deteriorate if insurgency and insecurity continue. The study therefore recommends that the government should do all it could to nurture its human capital, adequately fund the state security apparatus and employ individuals of high integrity to manage the various security outfits in Nigeria. The government should also as a matter of urgency train the security personnel in intelligence cum Information and Communications Technology to enable them ensure the effectiveness of implementation of security policies needed to sustain Gross Domestic Product and Human Capital Index of Nigeria.

Keywords: insecurity, insurgency, gross domestic product, human development index, Nigeria

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1795 Working Capital Management Effectiveness

Authors: Asif Iqbal

Abstract:

Working capital management has its effect on liquidity as well as on profitability of a firm. In this research we have selected a sample of 100 respondents whose firms are listed on Karachi stock exchange. We have studied the effect of different variable s of working capital management. We find that organizations throughout the world as well as in Pakistan have to give immense recognition to the working capital management as it is an effective thing from their long term perspective especially to their shareholders to have a firm confidence over the companies for investment purpose.

Keywords: working capital management, Karachi stock exchange, shareholders, capital management

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1794 Prediction Model of Body Mass Index of Young Adult Students of Public Health Faculty of University of Indonesia

Authors: Yuwaratu Syafira, Wahyu K. Y. Putra, Kusharisupeni Djokosujono

Abstract:

Background/Objective: Body Mass Index (BMI) serves various purposes, including measuring the prevalence of obesity in a population, and also in formulating a patient’s diet at a hospital, and can be calculated with the equation = body weight (kg)/body height (m)². However, the BMI of an individual with difficulties in carrying their weight or standing up straight can not necessarily be measured. The aim of this study was to form a prediction model for the BMI of young adult students of Public Health Faculty of University of Indonesia. Subject/Method: This study used a cross sectional design, with a total sample of 132 respondents, consisted of 58 males and 74 females aged 21- 30. The dependent variable of this study was BMI, and the independent variables consisted of sex and anthropometric measurements, which included ulna length, arm length, tibia length, knee height, mid-upper arm circumference, and calf circumference. Anthropometric information was measured and recorded in a single sitting. Simple and multiple linear regression analysis were used to create the prediction equation for BMI. Results: The male respondents had an average BMI of 24.63 kg/m² and the female respondents had an average of 22.52 kg/m². A total of 17 variables were analysed for its correlation with BMI. Bivariate analysis showed the variable with the strongest correlation with BMI was Mid-Upper Arm Circumference/√Ulna Length (MUAC/√UL) (r = 0.926 for males and r = 0.886 for females). Furthermore, MUAC alone also has a very strong correlation with BMI (r = 0,913 for males and r = 0,877 for females). Prediction models formed from either MUAC/√UL or MUAC alone both produce highly accurate predictions of BMI. However, measuring MUAC/√UL is considered inconvenient, which may cause difficulties when applied on the field. Conclusion: The prediction model considered most ideal to estimate BMI is: Male BMI (kg/m²) = 1.109(MUAC (cm)) – 9.202 and Female BMI (kg/m²) = 0.236 + 0.825(MUAC (cm)), based on its high accuracy levels and the convenience of measuring MUAC on the field.

Keywords: body mass index, mid-upper arm circumference, prediction model, ulna length

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1793 Assessment of Level of Sedation and Associated Factors Among Intubated Critically Ill Children in Pediatric Intensive Care Unit of Jimma University Medical Center: A Fourteen Months Prospective Observation Study, 2023

Authors: Habtamu Wolde Engudai

Abstract:

Background: Sedation can be provided to facilitate a procedure or to stabilize patients admitted in pediatric intensive care unit (PICU). Sedation is often necessary to maintain optimal care for critically ill children requiring mechanical ventilation. However, if sedation is too deep or too light, it has its own adverse effects, and hence, it is important to monitor the level of sedation and maintain an optimal level. Objectives: The objective is to assess the level of sedation and associated factors among intubated critically ill children admitted to PICU of JUMC, Jimma. Methods: A prospective observation study was conducted in the PICU of JUMC in September 2021 in 105 patients who were going to be admitted to the PICU aged less than 14 and with GCS >8. Data was collected by residents and nurses working in PICU. Data entry was done by Epi data manager (version 4.6.0.2). Statistical analysis and the creation of charts is going to be performed using SPSS version 26. Data was presented as mean, percentage and standard deviation. The assumption of logistic regression and the result of the assumption will be checked. To find potential predictors, bi-variable logistic regression was used for each predictor and outcome variable. A p value of <0.05 was considered as statistically significant. Finally, findings have been presented using figures, AOR, percentages, and a summary table. Result: in this study, 105 critically ill children had been involved who were started on continuous or intermittent forms of sedative drugs. Sedation level was assessed using a comfort scale three times per day. Based on this observation, we got a 44.8% level of suboptimal sedation at the baseline, a 36.2% level of suboptimal sedation at eight hours, and a 24.8% level of suboptimal sedation at sixteen hours. There is a significant association between suboptimal sedation and duration of stay with mechanical ventilation and the rate of unplanned extubation, which was shown by P < 0.05 using the Hosmer-Lemeshow test of goodness of fit (p> 0.44).

Keywords: level of sedation, critically ill children, Pediatric intensive care unit, Jimma university

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