Search results for: crest factor reduction

Authors: Zhidong Zhang, Amanda Resendez

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This study is to examine how teachers’ perspective on education technology use in their class influence their students’ achievement. The authors hypothesized that teachers’ perspective can directly or indirectly influence students’ learning, performance, and achievements. In this study, a questionnaire entitled, Teacher’s Perspective on Educational Technology, was delivered to 63 teachers and 1268 students’ mathematics and reading achievement records were collected. The questionnaire consists of four parts: a) demographic variables, b) attitudes on technology integration, c) outside factor affecting technology integration, and d) technology use in the classroom. Kruskal-Wallis and hierarchical regression analysis techniques were used to examine: 1) the relationship between the demographic variables and teachers’ perspectives on educational technology, and 2) how the demographic variables were causally related to students’ mathematics and reading achievements. The study found that teacher demographics were significantly related to the teachers’ perspective on educational technology with p < 0.05 and p < 0.01 separately. These teacher demographical variables included the school district, age, gender, the grade currently teach, teaching experience, and proficiency using new technology. Further, these variables significantly predicted students’ mathematics and reading achievements with p < 0.05 and p < 0.01 separately. The variations of R² are between 0.176 and 0.467. That means 46.7% of the variance of a given analysis can be explained by the model.

Keywords: teacher's perception of technology use, mathematics achievement, reading achievement, Kruskal-Wallis test, hierarchical regression analysis

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Authors: Michelle Marquard

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The evidence for collaboration technologies (CTs) as a source of business productivity has never been stronger, and grows each day. At the same time, paradoxically, there is an increasingly greater concern about the challenge CTs present to the unity and well-being of the virtual workforce than ever before, but nowhere in the literature has an empirical understanding of these linkages been set out. This study attempted to address by using virtual distance as a measure of the efficacy of CTs to reduce the psychological distance among people. Data from 350 managers and 101 individual contributors across twelve functions in six major industries showed that business value is related to collaboration (r=.84, p < .01), which, in turn, is associated with full spectrum participation (r=.60, p < .01), a summative function of inclusion, integration, and we-intention. Further, virtual distance is negatively related to both collaboration (r=-.54, p < .01) and full spectrum participation (r=-.26, p < .01). Additionally, CIO-CDO relationship is a factor in the degree to which virtual distance is managed in the organization (r=-.26, p < .01). Overall, the results support the positive relationship between business value and collaboration. They also suggest that the extent to which collaboration can be fostered may depend on the degree of full spectrum participation or the level of inclusion, integration, and we-intention among members. Finally, the results indicate that CTs, when managed wisely to lower virtual distance, are a compelling concomitant to collaboration and full spectrum participation. A strategic outcome of this study is an instrumental blueprint of CTs and virtual distance in relation to full spectrum participation that should serve as a shared dashboard for CIOs, CHROs, and CDOs.

Keywords: business value, collaboration, inclusion, integration, we-intention, full spectrum participation, collaboration technologies, virtual distance

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Authors: Fatemeh Abdollahi, Munn-Sann Lye, Jamshid Yazdani Charati, Mehran Zarghami

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Background: The negative consequences of intimate partner violence (IPV) on children have not been studied extensively. This study aimed to determine the prevalence of different types of IPV and its association with children’s growth and developmental problems. Methods: In a descriptive-analytical study, 596 mothers of one-year-old children referred to the primary health centers in Gonbad-e- Kavoos city were recruited (2018). The data were collected using the World Health Organization Domestic Violence, Ages and Stages Questionnaire-12 and the socio-economic, obstetrics, demographic and anthropometric characteristics related questionnaire. BMI Z-Score was categorized into three grades; thin (Z<-2), normal (-2≤Z<1), and overweight-obese (Z≥1). The data were analyzed using descriptive analysis, chi-square test, and regression. Results: The prevalence of physical, psychological, and sexual IPV was 7.4%, 29.5%, and 2.4%, respectively. Most of the children were of normal weight at one-year-old (91.7%). Similarly, the prevalence of overweight and obese was 13.3% and 8%, respectively. 2% of children had developmental problems at age one. There was a significant relationship between the father’s education and occupation and IPV and children’s delay in growth, respectively. There was no significant difference between BMI Z-Score and developmental disabilities in the children in women exposed and not exposed to all types of IPV. Conclusions: The prevalence of psychological IPV was common. IPV and children’s growth problems were influenced by the father’s socio-economic status. Preventing psychological IPV as a forerunner of other types of IPV and improving the economic situation may help in the reduction of these difficulties.

Keywords: children, development, growth, intimate partner violence

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Authors: Tilouche Rahma, Sayeb Soumaya, Ben Hassen Mohamed

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The wettability of materials is a very important aspect of surface science, it presents a key factor providing the best characteristic of product, especially in hygienic field. Hydrophobic polypropylene is used as nonwoven topsheet in disposable diaper, for its interesting properties (toughness, lightness...) by comparing with traditional product previously used. SURFACTANTs are widely used to reduce contact angle (water contact angles larger than 90° on smooth surfaces) and to change wetting properties. In the present work, we study ways to obtain hydrophilic polypropylene surface, by the deposition of a variety of surfactant on surfaces of varying morphology. We used two different methods for surface wetting: Spraying method and the coating method. The concentration of the wetting agent, the type of non-woven fabric and the parameters in the method for controlling, hugely affect the quality of treatment. Therefore need that the treatment is effective in terms of contact angle without affecting the mechanical properties of the nonwoven. For the assessment of the quality of treatment, two methods are used: The measurement of the contact angle and the strike trough time. Also, with subjective evaluation by Hedonic test (which involves the consumer preference (naive panel: group of moms). Finally, we selected the better treated topsheet referring to the assessment results.

Keywords: SURFACTANT, topsheet polypropylene, hydrophilic, hydrophobic

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Authors: I. Wayan Wiwin

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Poverty is one of the big problems faced by big cities in the world. Urbanization one cause, many rural communities trying to earn a living to the city in the hope that they can improve the level of economy, but not equipped with adequate skills so that it becomes an urban demographic problem. Denpasar as the capital of the province of Bali one of them, in the city area of Denpasar there are many slum dwellings inhabited by the poor, whereas Bali is known as one of the best tourist destinations in the world. This condition is very inversely proportional to the progress of tourism in Bali. For that it is necessary to attempt to overcome poverty in the city of Denpasar, one with the development of city tours in the form of charity walking tours, where tourists are invited to take a walk to see directly the state of the poor in the city of Denpasar and provide assistance to them in the form of home assistance, educational scholarships, health assistance, as well as skill and business capital assistance. This research is explorative-qualitative, that is exploring the potential of charity walking tour to overcome poverty in Denpasar City, which is written qualitatively. In the end based on potential data and information, then analyzed into a decision whether it is possible to develop. Therefore, this study only requires respondents or informants who are able to provide answers or qualitative information about matters related to the potential development of charity walking tour. Thus, informants in this study are tourism stakeholders, such as Municipal government officials, businessmen, community leaders and tourism actors, who are considered to be providing information relating to the development of urban tourism.

Keywords: tourism, city tours, charity walking tours, poverty

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Authors: Ophir Nave

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In our research, we present the concept of singularly perturbed vector field (SPVF) method, and its application to thermal explosion of diesel spray combustion. Given a system of governing equations, which consist of hidden Multi-scale variables, the SPVF method transfer and decompose such system to fast and slow singularly perturbed subsystems (SPS). The SPVF method enables us to understand the complex system, and simplify the calculations. Later powerful analytical, numerical and asymptotic methods (e.g method of integral (invariant) manifold (MIM), the homotopy analysis method (HAM) etc.) can be applied to each subsystem. We compare the results obtained by the methods of integral invariant manifold and SPVF apply to spray droplets combustion model. The research deals with the development of an innovative method for extracting fast and slow variables in physical mathematical models. The method that we developed called singular perturbed vector field. This method based on a numerical algorithm applied to global quasi linearization applied to given physical model. The SPVF method applied successfully to combustion processes. Our results were compared to experimentally results. The SPVF is a general numerical and asymptotical method that reveals the hierarchy (multi-scale system) of a given system.

Keywords: polydisperse spray, model reduction, asymptotic analysis, multi-scale systems

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Authors: Arpit Panwar, Arvind Deshpande

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The study of external vehicle aerodynamics using Spalart-Allmaras turbulence model with adjoint method was conducted. The accessibility and ease of working with the Fluent module of ANSYS and OpenFOAM were considered. The objective of the study was to understand and analyze the possibility of bringing high-level aerodynamic simulation to the average consumer vehicle. A form-factor of BMW M6 vehicle was designed in Solidworks, which was analyzed in OpenFOAM and Fluent. The turbulence model being a single equation provides much faster convergence rate when clubbed with the adjoint method. Fluent being commercial software still does not allow us to solve Spalart-Allmaras turbulence model using the adjoint method. Hence, the turbulence model was solved using the SIMPLE method in Fluent. OpenFOAM being an open source provide flexibility in simulation but is not user-friendly. It supports solving the defined turbulence model with the adjoint method. The result generated from the simulation gives us acceptable values of drag, when validated with the result of percentage error in drag values for a notch-back vehicle model on an extensive simulation produced at 6th ANSA and μETA conference, Greece. The success of this approach will allow us to bring more aerodynamic vehicle body design to all segments of the automobile and not limiting it to just the high-end sports cars.

Keywords: Spalart-Allmaras turbulence model, OpenFOAM, adjoint method, SIMPLE method, vehicle aerodynamic design

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Authors: Ankitsinh Chauhan, Vimal Patel, A. D. Parekh, Ishant patil

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This study delves into the crucial influence of cooling tower fan operation on the performance of a chiller plant, with a specific focus on the Chiller Plant at SVNIT. Continuous operation of the chiller plant led to unexpected damage to the cooling tower's belt drive, rendering the cooling tower fan non-operational. Consequently, the efficiency of heat transfer in the condenser was significantly impaired. In response, we analyzed and calculated several vital parameters, including the Coefficient of Performance (COP), heat rejection in the condenser (Qc), work required for the compressor (Wc), and heat absorbed by the refrigerant in the evaporator (Qe). Our findings revealed that in the absence of the cooling tower fan, relying solely on natural convection, the COP of the chiller plant reached a minimum value of 5.49. However, after implementing a belt drive to facilitate forced convection for the cooling tower fan, the COP of the chiller plant experienced a noteworthy improvement, reaching approximately 6.27. Additionally, the utilization of forced convection resulted in an impressive reduction of 8.9% in compressor work, signifying enhanced energy efficiency. This study underscores the critical role of cooling tower fan operation in optimizing chiller plant performance, with practical implications for energy-efficient HVAC systems. It highlights the potential benefits of employing forced convection mechanisms, such as belt drives, to ensure efficient heat transfer in the condenser, ultimately contributing to improved energy utilization and reduced operational costs in cooling.

Keywords: cooling tower, chiller Plant, cooling tower fan, energy efficiency, VCRS.

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Authors: Vinayak Bassi, Rajpreet Singh

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Over the years, with the emergence of sophisticated computers and algorithms, finance has been quantified using computational prowess. Asset valuation has been one of the key components of quantitative finance. In fact, it has become one of the embryonic steps in determining risk related to a portfolio, the main goal of quantitative finance. This study comprises a drawing comparison between valuation output generated by two stochastic dynamic models, namely Black-Scholes and Dupire’s bi-dimensionality model. Both of these models are formulated for computing the valuation function for a portfolio of European options using Monte Carlo simulation methods. Although Monte Carlo algorithms have a slower convergence rate than calculus-based simulation techniques (like FDM), they work quite effectively over high-dimensional dynamic models. A fidelity gap is analyzed between the static (historical) and stochastic inputs for a sample portfolio of underlying assets. In order to enhance the performance efficiency of the model, the study emphasized the use of variable reduction methods and customizing random number generators to implement parallelization. An attempt has been made to further implement the Dupire’s model on a GPU to achieve higher computational performance. Furthermore, ideas have been discussed around the performance enhancement and bottleneck identification related to the implementation of options-pricing models on GPUs.

Keywords: monte carlo, stochastic models, computational finance, parallel programming, scientific computing

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Authors: Naila Tallas Mahajna, Jamal Al Khateeb

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This study examined the level of social communication problems, social anxiety, and mood problems among children with ASD (age 6-13 years) enrolled in special classes (n=46) and regular classes (n=36) from teachers' perspective in the schools of a part of Palestine. Teachers responded to three questionnaires - social communication problems, social anxiety and mood problems- that were used to answer the research questions. Results: social communication problems, social anxiety and mood problems were of medium rates for students with ASD enrolled in reguler and special classes. No significant differences in the level of social communication problems could be attributed to class type (Regular, Special) or the grade level-(1st – 3rd, 4th - 6th). There were significant differences in social anxiety levels that could be attributed to grade level in favor of the 4th - 6th grades but there were no significant differences according to class type (Regular, Special). There were statistically significant differences in mood problems levels that could be attributed to the class type in favor of special classes, but no differences were found according to grade level. There was a direct significant relationship between communication problems, social anxiety, and mood problems. Conclusion: social communication problems may be an important risk factor for the development of social anxiety and mood problems among students with ASD.

Keywords: social communication problems, social anxiety, mood problems, autism spectrum disorders

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Authors: Alia Ali, Azeem Taj, Muhammed Joher Amin, Farrukh Iqbal, Zafar Iqbal

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Background: Hypertension is commonly found in patients with Diabetic Kidney Disease (DKD). Microalbuminuria is the first clinical sign of involvement of kidneys in patients with type 2 diabetes. Uncontrolled hypertension induces a higher risk of cardiovascular events, including death, increasing proteinuria and progression to kidney disease. Objectives: To determine the correlation between microalbuminuria and hypertension and their association with other risk factors in type 2 diabetic patients. Methods: One hundred and thirteen type 2 diabetic patients were screened for microalbuminuria and raised blood pressure, attending the diabetic clinic of Shaikh Zayed Hospital, Lahore, Pakistan. The study was conducted from November 2012 to June 2013. Results: Patients were divided into two groups. Group 1, those with normoalbuminuria (n=63) and Group 2, those having microalbuminuria (n=50). Group 2 patients showed higher blood pressure values as compared to Group 1. The results were statistically significant and showed poor glycemic control as a contributing risk factor. Conclusion: The study concluded that there is high frequency of hypertension among type 2 diabetics but still much higher among those having microalbuminuria. So, early recognition of renal dysfunction through detection of microalbuminuria and to start treatment without any delay will confer future protection from end-stage renal disease as well as hypertension and its complications in type 2 diabetic patients.

Keywords: hypertension, microalbuminuria, diabetic kidney disease, type 2 Diabetes mellitus

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Authors: Mehmet Erdi Korkmaz, Mustafa Günay

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Nowadays, grinding is frequently replaced with hard turning for reducing set up time and higher accuracy. This paper focused on mathematical modeling of average surface roughness (Ra) in hard turning of AISI L2 grade (DIN 1.2210) cold work tool steel with ceramic tools. The steel was hardened to 60±1 HRC after the heat treatment process. Cutting speed, feed rate, depth of cut and tool nose radius was chosen as the cutting conditions. The uncoated ceramic cutting tools were used in the machining experiments. The machining experiments were performed according to Taguchi L27 orthogonal array on CNC lathe. Ra values were calculated by averaging three roughness values obtained from three different points of machined surface. The influences of cutting conditions on surface roughness were evaluated as statistical and experimental. The analysis of variance (ANOVA) with 95% confidence level was applied for statistical analysis of experimental results. Finally, mathematical models were developed using the artificial neural networks (ANN). ANOVA results show that feed rate is the dominant factor affecting surface roughness, followed by tool nose radius and cutting speed.

Keywords: ANN, hard turning, DIN 1.2210, surface roughness, Taguchi method

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Authors: Renato André S. Silva, Nana L. F. Sampaio, Carlos J. G. Cruz, Bruno Vianna, Flávio O. Pires

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multiple stage bicycle races require high physiological loads from professional cyclists. Such demands can lead to immunosuppression and health problems. However, in this type of competition, little is known about its physiological effects on amateur athletes, who generally receive less medical support. Thus, this study analyzes the hematological effects of a multiple stage bicycle race on amateur cyclists. Seven Brazilian national amateur cyclists (34 ± 4.21 years) underwent a laboratory test to evaluate VO2Max (69.89 ± 7.43 ml⋅kg-1⋅min-1). Six days later, these volunteers raced in the Tour of Goiás, participating in five races in four days (435 km) of competition. Arterial blood samples were collected one day before and one day after the competition. The Kolmogorov-Smirnov tests were used to evaluate the data distribution and Wilcoxon to compare the two moments (p <0.05) of data collection. The results show: Red cells ↓ 7.8% (5.1 ± 0.28 vs 4.7 ± 0.37 106 / mm 3, p = 0.01); Hemoglobin ↓ 7.9% (15.1 ± 0.31 vs 13.9 ± 0.27 g / dL, p = 0.01); Leukocytes ↑ 9.5% (4946 ± 553 versus 5416 ± 1075 / mm 3, p = 0.17); Platelets ↓ 7.0% (200.2 ± 51.5 vs 186.1 ± 39.5 / mm 3, p = 0.01); LDH ↑ 11% (164.4 ± 28.5 vs 182.5 ± 20.5 U / L, p = 0.17); CK ↑ 13.5% (290.7 ± 206.1 vs 330.1 ± 90.5 U / L, p = 0.39); CK-MB ↑ 2% (15.7 ± 3.9 vs. 20.1 ± 2.9 U / L, p = 0.06); Cortizol ↓ 13.5% (12.1 ± 2.4 vs 9.9 ± 1.9 μg / dL, p = 0.01); Total testosterone ↓ 7% (453.6 ± 120.1 vs 421.7 ± 74.3 ng / dL, p = 0.12); IGF-1 ↓ 15.1% (213.8 ± 18.8 vs 181.5 ± 34.7 ng / mL, p = 0.04). This means that there was significant reductions in O2 allocation / transport capacities, vascular injury disruption, and a fortuitous reduction of muscle skeletal anabolism along with maintenance and / or slight elevation of immune function, glucose and lipid energy and myocardial damage. Therefore, the results suggest that no abnormal health effect was identified among the athletes after participating in the Tour de Goiás.

Keywords: cycling, health effects, cycling stages races, haematology

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Authors: Zahzouh Zoubir, Bouzaouit Azzeddine, Gahgah Mounir

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The use of more and more electronic power switches with a nonlinear behavior generates non-sinusoidal currents in distribution networks, which causes damage to domestic and industrial equipment. The multi-level shunt power active filter is subsequently shown to be an adequate solution to the problem raised. Nevertheless, the difficulty of adjusting the active filter DC supply voltage requires another technology to ensure it. In this article, a photovoltaic generator is associated with the DC bus power terminals of the active filter. The proposed system consists of a field of solar panels, three multi-level voltage inverters connected to the power grid and a non-linear load consisting of a six-diode rectifier bridge supplying a resistive-inductive load. Current control techniques of active and reactive power are used to compensate for both harmonic currents and reactive power as well as to inject active solar power into the distribution network. An algorithm of the search method of the maximum power point of type Perturb and observe is applied. Simulation results of the system proposed under the MATLAB/Simulink environment shows that the performance of control commands that reassure the solar power injection in the network, harmonic current compensation and power factor correction.

Keywords: Actif power filter, MPPT, pertub&observe algorithm, PV array, PWM-control

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Authors: Sujen Man Shrestha, Kanchan Thapa, Tista Prasai Joshi

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Background: The present study was carried out to determine suspended particles and respirable particles of diameter less than 1 micrometers (PM1) on road side and some distance of outside from road; and to compare the respiratory symptoms between traffic police men and shop keepers directly 'exposed' to traffic fumes and office worker stay in 'protected' enclosed environment. Methods: Semi structured questionnaire was used to collect the data among case and control after getting verbal informed consent among the convenience sample of traffic police, shopkeepers and officials in three different locations in Kathmandu. Secondary data analysis of hospital data of three hospitals of Kathmandu was also performed. The data on air Particulate Matter was taken by Haz Dust. Results: The result showed air quality of road side traffic is unhealthy and there was increasing trends of respiratory illness in hospital outpatient department (OPD). The people who were exposed found to have more risk of developing respiratory diseases symptoms. Conclusions: The study concluded that air pollution level is strong contributing factor for respiratory diseases and further recommended strong, epidemiological studies with larger sample size, less bias, and also measuring other significant physical and chemicals parameters of air pollution.

Keywords: heavy traffic cities, Kathmandu, particulate pollution, respiratory symptoms

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Authors: Santosh Sharma Parajuli, Diwas Manandhar

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Background: Perioperative pain management plays an integral part in patients undergoing cardiac surgery. We studied the effect of Erector Spinae Plane block on acute postoperative pain reduction and 24 hours opioid consumption in adult cardiac surgical patients. Methods: Twenty-five adult cardiac surgical patients who underwent cardiac surgery with sternotomy in whom ESP catheters were placed preoperatively were kept in group E, and the other 25 patients who had undergone cardiac surgery without ESP catheter and pain management done with conventional opioid injection were placed in group C. Fentanyl was used for pain management. The primary study endpoint was to compare the consumption of fentanyl and to assess the numeric rating scale in the postoperative period in the first 24 hours in both groups. Results: The 24 hours fentanyl consumption was 43.00±51.29 micrograms in the Erector Spinae Plane catheter group and 147.00±60.94 micrograms in the control group postoperatively which was statistically significant (p <0.001). The numeric rating scale was also significantly reduced in the Erector Spinae Plane group compared to the control group in the first 24 hours postoperatively. Conclusion: Erector Spinae Plane block is superior to the conventional opioid injection method for postoperative pain management in CABG patients. Erector Spinae Plane block not only decreases the overall opioid consumption but also the NRS score in these patients.

Keywords: erector, spinae, plane, numerical rating scale

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Authors: Osama M. Ahmed, Walaa G. Hozayen, Haidy Tamer Abo Sree

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Doxorubicin (DOX), an anthracycline antibiotic is a broad-spectrum antineoplastic agent, which is commonly used in the treatment of uterine, ovarian, breast and lung cancers, Hodgkin's disease and soft tissue sarcomas as well as in several other cancer types. The effect of doxorubicin (4 mg/kg b.w.week) without or with oral administration of ethanolic purslane (Portulaca oleracea) shoot (leaves and stems) extract (50 mg/kg b.w. day) or ethanolic purslane seeds extract (50 mg/kg b.w.day) co-treatments for 6 weeks was evaluated in adult male rats. Serum ALT, AST, ALP, GGT, total bilirubin, total protein, and albumin levels were assayed. Lipid peroxidation (indexed by MDA) and antioxidants like hepatic glutathine, glutathione transferase, peroxidase, SOD, and CAT were assessed. There was an increase in serum levels of ALT, AST, ALP, GGT and total bilirubin. In addition, hepatic glutathine, glutathione transferase, peroxidase, SOD, and CAT activities were decreased while lipid peroxidation in the liver was increased. Co-administration of ethanolic purslane and seed extracts successfully improved the adverse changes in the liver functions with an increase in antioxidants activities and reduction of lipid peroxidation. In conclusion, it can be supposed that dietary purslane extract supplementation may provide a cushion for a prolonged therapeutic option against DOX hepatopathy without harmful side effects. However, further clinical studies are required to assess the safety and efficacy of these extract in human beings.

Keywords: doxorubicin, purslane, hepatotoxicity, antioxidants

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Authors: Michel Han, Christophe Besson, Alain Savary, Yvan Becher

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The variable flux permanent magnet synchronous motor (VF-PMSM), also called "Memory Motor", is a new generation of motor capable of modifying the magnetization state with short pulses of current during operation or standstill. The impact of such operation is the expansion of the operating range in the torque-speed characteristic and an improvement in energy efficiency at high-speed in comparison to conventional permanent magnet synchronous machines (PMSMs). This paper reviews the operating principle and the unique features of the proposed memory motor. The benefits of this concept are highlighted by comparing the performance of the rotor of the VF-PMSM to that of two PM rotors that are typically found in the industry. The investigation emphasizes the properties of the variable magnetization and presents the comparison of the torque-speed characteristic with the capability of loss reduction in a VF-PMSM by means of experimental results, especially when tests are conducted under identical conditions for each rotor (same stator, same inverter and same experimental setup). The experimental results demonstrated that the VF-PMSM gives an additional degree of freedom to optimize the efficiency over a wide speed range. Thus, with a design easy to manufacture and with the possibility of controlling the magnetization and the demagnetization of the magnets during operations, the VF-PMSM can be interesting for various applications.

Keywords: efficiency, magnetization state, memory motors, performances, permanent-magnet, synchronous machine, variable-flux, variable magnetization, wide speed application

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Authors: Dongwan Kang, Joohyung Oh, Chaetae Im

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Advancement of communication technologies and smart devices in the recent times is leading to changes into the integrated wired and wireless communication environments. Since early days, businesses had started introducing environments for mobile device application to their operations in order to improve productivity (efficiency) and the closed corporate environment gradually shifted to an open structure. Recently, individual user's interest in working environment using mobile devices has increased and a new corporate working environment under the concept of BYOD is drawing attention. BYOD (bring your own device) is a concept where individuals bring in and use their own devices in business activities. Through BYOD, businesses can anticipate improved productivity (efficiency) and also a reduction in the cost of purchasing devices. However, as a result of security threats caused by frequent loss and theft of personal devices and corporate data leaks due to low security, companies are reluctant about adopting BYOD system. In addition, without considerations to diverse devices and connection environments, there are limitations in detecting abnormal behaviors such as information leaks which use the existing network-based security equipment. This study suggests a method to detect abnormal behaviors according to individual behavioral patterns, rather than the existing signature-based malicious behavior detection and discusses applications of this method in BYOD environment.

Keywords: BYOD, security, anomaly behavior detection, security equipment, communication technologies

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Authors: Henriette Hammill

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Background: Safe landing in netball is fundamental. Research on the biomechanics of multidirectional landings is lacking, especially among netball players. Furthermore, few studies reporting the associations between lower extremity injuries and landing kinematics and kinetics in university-level netball players have been undertaken. Objectives: The aim is to determine the relationships between lower extremity injuries and landing kinematics and kinetics in university-level netball players that have been undertaken during a single season. Methods: This cross-sectional repeated measure study consisted of ten university-level female netball players. The injury prevalence data was collected during the 2022 netball season. The kinematic and kinetic data were collected during multidirectional single-leg landing trials and was collected. Results: Generally, the ankle strength of netball players was below average. There was evidence of negative correlations between the ankle range of motion (ROM), and muscle activity amplitudes. A lack of evidence precluded the conclusion that lower extremity dominance was a predisposing factor for injury and that any specific body part was most likely to be injured among netball players. Conclusion: Landing forces and muscle activity are direction-dependent, especially for the dominant extremity. Lower extremity strength and neuromuscular control (NMC) across multiple jump-landing directions should be an area of focus for female netball players.

Keywords: netball players, landing kinetics, landing kinematics, lower extremity

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Authors: Yun Sun, Meng Xun, Jingtao Zhou, Ming Li, Qiang Kan, Zhi Jin, Xinyu Liu, Dexin Wu

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Higher speed short-wavelength vertical-cavity surface-emitting lasers (VCSELs) working at high temperature are required for future optical interconnects. In this work, the high-speed 850 nm VCSELs are designed, fabricated and characterized. The temperature dependent static and dynamic performance of devices are investigated by using current-power-voltage and small signal modulation measurements. Temperature-stable high-speed properties are obtained by employing highly strained multiple quantum wells and short cavity length of half wavelength. The temperature dependent photon lifetimes and carrier radiative times are determined from damping factor and resonance frequency obtained by fitting the intrinsic optical bandwidth with the two-pole transfer function. In addition, an analytical theoretical model including the strain effect is development based on model-solid theory. The calculation results indicate that the better high temperature performance of VCSELs can be attributed to the strong confinement of holes in the quantum wells leading to enhancement of the carrier transit time.

Keywords: vertical cavity surface emitting lasers, high speed modulation, optical interconnects, semiconductor lasers

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Authors: Myoungsoon You, Heejung Son

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During a pandemic, hospital workers should protect not only their vulnerable patients but also themselves from the consequences of rapidly spreading infection. However, the evidence on the psychological impact of an outbreak on hospital workers is limited. In this study, we aim to assess hospital workers’ psychological well-being and function at the workplace after an outbreak, by focusing on ‘psychological resilience’. Specifically, the effects of risk appraisal, emotional experience, and coping ability on resilience indicated by the likelihood of post-traumatic syndrome disorder and willingness to work were investigated. Such role and position of each factor were analyzed using a path model, and the result was compared between the healthcare worker and non-healthcare worker groups. In the investigation, 280 hospital workers who experienced the 2015 Middle East Respiratory Syndrome outbreak in South Korea have participated. The result presented, in both groups, the role of the appraisal of risk and coping ability appeared consistent with a previous research, that was, the former interrupted resilience while the latter facilitated it. In addition, the role of emotional experience was highlighted as, in both groups, emotional disruption not only directly associated with low resilience but mediated the effect of perceived risk on resilience. The differences between the groups were also identified, which were, the role of emotional experience and coping ability was more prominent in the non-HCW group in explaining resilience. From the results, implications on how to support hospital personnel during an outbreak in a way to facilitate their resilience after the outbreak were drawn.

Keywords: hospital workers, emotions, infectious disease outbreak, psychological resilience

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Authors: Gokhan Sir, Muhammed Ergun, Onder Balioglu

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Nowadays, laundry dryers containing heaters and heat pumps are used to provide fast and efficient drying. In this system, as the drying capacity changes, the sensible and latent heat transfer rate in the evaporator changes. Therefore, the drying time measured for the unit capacity increases as the drying capacity decreases. The objective of this study is to investigate the evaporator efficiency according to load amount and textile type in hybrid heat pump dryers. Air side flow rate and system temperatures (air side and refrigeration side) were monitored instantly, and the specific moisture extraction rate (SMER), evaporator efficiency, and heat transfer mechanism between the textile and hybrid heat pump system were examined. Evaporator efficiency of heat pump dryers for cotton and synthetic based textile types in load amounts of 2, 5, 8 and 10 kg were investigated experimentally. As a result, the maximum evaporator efficiency (%72) was obtained in drying cotton and synthetic based textiles with a capacity of 5 kg; the minimum evaporator efficiency (%40) was obtained in drying cotton and synthetic based textiles with a capacity of 2 kg. The experimental study also reveals that capacity-dependent flow rate changes are the major factor for evaporator efficiency.

Keywords: evaporator, heat pump, hybrid, laundry dryer, textile

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Authors: F. Forouharmajd, S. Pourabdian, N. Ziayi Ghahnavieh

Abstract:

For many years, the ear protectors have been used to preventing the audio and non-audio effects of received noise from occupation environments. Despite performing hearing protection programs, there are many people which still suffer from noise-induced hearing loss. This study was conducted with the aim of determination of human hearing system response to received noise and the effectiveness of ear protectors on preventing of noise-induced hearing loss. Sound pressure microphones were placed in a simulated ear canal. The severity of noise measured inside and outside of ear canal. The noise reduction values due to installing ear protectors were calculated in the octave band frequencies and LabVIEW programmer. The results of noise measurement inside and outside of ear canal showed a different in received sound levels by ear canal. The effectiveness of ear protectors has been considerably reduced for the low frequency limits. A change in resonance frequency also was observed after using ear protectors. The study indicated the ear canal structure may affect the received noise and it may lead a difference between the received sound from the measured sound by a sound level meter, and hearing system. It means the human hearing system may probably respond different from a sound level meter. Hearing protectors’ efficiency declines by increasing the noise levels, and thus, they are not suitable to protect workers against industrial noise particularly low frequency noise. Hearing protectors may be solely a reason to damaging of hearing system in a special frequency via changing of human hearing system acoustical structure. We need developing the subjective method of hearing protectors testing, because their evaluation is not designed based on industrial noise or in the field.

Keywords: ear protector, hearing system, occupational noise, workers

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Authors: Soham Lalwala, Ronita Singh, Yaman Pattanaik

Abstract:

In the present scenario of globalization and privatization, it becomes difficult for small scale industries to sustain due to rapidly increasing competition. In a developing country, most of the gross output is generally obtained from small scale industries. Thus, quality plays a vital role in maintaining customer satisfaction. Total quality management (TQM) is an approach which enables employees to focus on quality rather quantity, further improving the competitiveness, effectiveness and flexibility of the whole organization. The objective of the paper is to present the application of TQM and develop a TQM Model in a small scale industry of narrow fabrics in Surat, India named ‘Rajdhani Lace & Borders’. Further, critical success factors relating all the fabric processes involved were identified. The data was collected by conducting a questionnaire survey. After data was collected, critical areas were visualized using different tools of TQM such as cause and effect diagram, control charts and run charts. Overall, responses were analyzed, and factor analysis was used to develop the model. The study presented here will aid the management of the above-mentioned industry in identifying the weaker areas and thus give a plausible solution to improve the total productivity of the firm along with effective utilization of resources and better customer satisfaction.

Keywords: critical success factors, narrow fabrics, quality, small scale industries, total quality management (TQM)

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Authors: Ifeanyi Charles Otuokere, Victoria Nneoma Nnochiri

Abstract:

Entrepreneurship generally and specifically within the rural communities in Nigeria is a fast means of bringing development within the communities. This is made possible by utmost maximization and management of available local resources to develop rural areas through good management of these local resources. This study anchors on the rural development paradigm and the integrated rural development theories to understudy the knowledge of rural entrepreneurs on rural economic development. The research study made use of surveys and descriptive analysis. The assessable population for the study, which was randomly selected, is 100 rural entrepreneurs from ten rural communities within the Ikwuano Local Government Area of Abia State. The study made use of both primary and secondary as a source of data collection with much emphasis on a primary source, although secondary data such as journals, textbooks electronic sources were also utilised. A carefully structured questionnaire drafted to extract raw data was administered to selected entrepreneurs. The findings of the study showed that developments within rural communities can only be achieved through rural entrepreneurship. This is evidenced in increased output, job creation, and most importantly, reduction of rural to urban migration, among other things. Recommendations were also made based on these findings; the researchers recommended that infrastructural developments should be made available in the rural communities and government policies should create enabling environments along with other assistance to help these rural entrepreneurs achieve their sole aim.

Keywords: economic developments, rural communities, rural development, rural entrepreneurship

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Authors: N. M. Aborehab, M. Helmy, N. E. Waly

Abstract:

Resistin was identified as an adipocyte hormone that participates in regulation of glucose metabolism. Elevated levels of Resistin are postulated to cause insulin resistance. This may link obesity, and increased fat mass to type II diabetes and insulin resistance. We hypothesized that tomato and broccoli extract treatment regulates glucose homeostasis via modulation of resistin levels in high fat diet induced obesity rats (HFD). 63 male albino rats were divided into 8 groups as follows: control, HFD, stop fat diet (SD), Tomato 200 mg/kg (T200), Tomato 400mg/kg (T400), Broccoli 200 mg/kg (B200), Broccoli 400 mg/kg (B400), Chromax (CX). Treatment continued for 1 month. Serum levels of resistin, leptin, adiponectin, glucose and insulin were measured using ELISA, and spectrophotometry. Serum level of resistin was significantly reduced in T 200, T 400, B 200, B 400 and CX groups to: 4.13 ± 0.22 ng/ml, 1.51 ± 0.04 ng/ml, 4.13 ± 0.22 ng/ml, 2.32 ± 0.15 ng/ml and 1.37 ± 0.03 ng/ml respectively compared to HFD group and SD group (P value < 0.0001). Non-significant difference was found between T 400, B 400 and CX groups. Mean serum level of leptin was significantly reduced in T 400 (22.7 ± 0.84 Pg/ml) group compared to B 400 (41 ± 2.45 Pg/ml) and CX groups (45.7 ± 2.91 Pg/ml), P value < 0.001.The mean serum level of adiponectin was significantly increased in T 400 group (131 ± 3.84 Pg/ml) compared to CX group (112 ± 4.77 Pg/ml), P value was < 0.01. Our results demonstrate that tomato and broccoli extract treatment regulates glucose homeostasis via reduction of serum resistin and may be a useful non-pharmacological therapy for obesity. Further studies are required to assess the potential use of these extract as a treatment for type II diabetes and obesity.

Keywords: broccoli, obesity, resistin, tomato

Procedia PDF Downloads 302

Authors: Sarmin, S., Ologuin, R.S.

Abstract:

Background: Rapid population growth and land constraints in Singapore results in a possible situation in which we face a higher number of casualties and lack of operational space in healthcare facilities during disasters and HAZMAT events, collectively known as Civil Emergencies. This creates a need for available working space within hospital grounds to be amphibious or multi-functional, to ensure the institution’s capability to respond efficiently to Civil Emergencies. The Emergency Department (ED) mitigates this issue by converting the Ambulance Assembly Area used during peacetime into an Open Decontamination Facility (ODF) during Civil Emergency Response, for decontamination of casualties before they proceed to treatment areas into Ambulance Assembly Area used during peacetime. Aims: To effectively operationalize the Open Decontamination Facility (ODF) through the reduction of manual handling. Methods: From past experiences on Civil Emergency exercises, it was labor-intensive for staff to set up the Open Decontamination Facility (ODF). Manual handling to set up the Decontamination lanes by bringing down the curtains and supply of water was required to be turned on. Conclusion: The effectiveness of the design construction of an Open Decontamination Facility (ODF) is based on the use of automation of bringing down the curtains on the various lanes. The use of control panels for water supply to decontaminate patients. Safety within the ODF was considered with the installation of panic buttons, intercom for staff communication, and perimeter curtains were installed with stability arm to manage the condition with high wind velocity.

Keywords: civil emergencies, disaster, emergency department, Hazmat

Procedia PDF Downloads 100

Authors: H. Higashiyama, M. Sano, F. Nakanishi, M. Sugiyama, M. Kawanishi, S. Tsukuma

Abstract:

The heat island phenomenon and extremely hot summer climate are becoming environmental problems in Japan. Cool pavements reduce the surface temperature compared to conventional asphalt pavements in the hot summer climate and improve the thermal environment in the urban area. The authors have studied cement–based grouting materials poured into voids in porous asphalt pavements to reduce the road surface temperature. For the cement–based grouting material, cement, ceramic waste powder, and natural zeolite were used. This cement–based grouting material developed reduced the road surface temperature by 20 °C or more in the hot summer season. Considering the urban landscape, this study investigates the effect of surface temperature reduction of colored cement–based grouting materials containing pigments poured into voids in porous asphalt pavements by measuring the surface temperature of asphalt pavements outdoors. The yellow color performed the same as the original cement–based grouting material containing no pigment and was thermally better performance than the other color. However, all the tested cement–based grouting materials performed well for reducing the surface temperature and for creating the urban landscape.

Keywords: ceramic waste powder, natural zeolite, road surface temperature, asphalt pavement, urban landscape

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Authors: Ubeyd Toçoğlu, Miraç Alaf, Hatem Akbulut

Abstract:

We present a work which was conducted in order to improve the cycle life of silicon based lithium ion battery anodes by utilizing novel composite structure. In this study, carbon coated nano sized (50-100 nm) silicon particles were embedded into Graphene/MWCNT silicon matrix to produce free standing silicon based electrodes. Also, conventional Si powder anodes were produced from Si powder slurry on copper current collectors in order to make comparison of composite and conventional anode structures. Free –standing composite anodes (binder-free) were produced via vacuum filtration from a well dispersion of Graphene, MWCNT and carbon coated silicon powders. Carbon coating process of silicon powders was carried out via microwave reaction system. The certain amount of silicon powder and glucose was mixed under ultrasonication and then coating was conducted at 200 °C for two hours in Teflon lined autoclave reaction chamber. Graphene which was used in this study was synthesized from well-known Hummers method and hydrazine reduction of graphene oxide. X-Ray diffraction analysis and RAMAN spectroscopy techniques were used for phase characterization of anodes. Scanning electron microscopy analyses were conducted for morphological characterization. The electrochemical performance tests were carried out by means of galvanostatic charge/discharge, cyclic voltammetry and electrochemical impedance spectroscopy.

Keywords: graphene, Li-Ion, MWCNT, silicon

Procedia PDF Downloads 256