Search results for: physical tests
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10005

Search results for: physical tests

2655 The Effect of Santolina Plant Extract on Nitro-Oxidative Stress

Authors: Sabrina Sebbane, Alina Elena Parvu

Abstract:

Introduction: Santolina rosmarinifolia is a plant of the Santolina genus, a family made of medicinal plants widely used. Some of the Santolina species have been proven to have potent anti-inflammatory and anti-oxidant effects. However, no in vivo study has been made to demonstrate this in Santolina rosmarinifolia. The aim of our study is to experimentally evaluate the potential anti-inflammatory and anti-oxidant effects of Santolina rosmarinifolia plant extracts on acute inflammation in rats. These effects are defined by measuring the modifications on nitric oxide, reactive oxygen species and anti-oxidant response in serum. Materials and Methods: Rats were divided into 5 groups (n=6). Three groups were given Santolina rosmarinifolia extract by gavage in different concentrations(100%, 50%, 25%) for a week. Inflammation was induced by i.m injection of turpentine oil on the 8th day. One group was only given turpentine oil and the fifth group acted as control and was given only saline solution. Blood was collected and serum separated. Global tests were used to measure the oxidative stress, total oxidative status (TOS), total antioxidant reactivity (TAR) and the modified method of Griess assay to measure NO synthesis. Malondilaldehyde (MDA) and thiols levels were also assessed. Results: Santolina rosmarinifolia did not significantly change the TOS levels (p > 0.05). Santolina rosmarinifolia 25% and 50% decreased significantly the TAR levels (p < 0.001). Santolina 100% didn't have a significant effect on TAR (p > 0.05). All concentrations of Santolina rosmarinifolia increased the oxidative stress index (OSI) significantly(p < 0.05). Santolina rosmarinifolia 100% significantly decreased NO synthesis (p value < 0.05). In the diluted Santolina groups, no significant effect on NO synthesis was observed. In the groups treated with Santolina 100% and Santolina rosmarinifolia 50%, thiols concentration were significantly higher compared to the inflammation group (p < 0.02). A higher stimulatory effect was found in the Santolina 25% group (p value < 0.05). MDA levels were not significantly modified by the administration of Santolina rosmarinifolia (p > 0.05). Conclusion: All three solutions of Santolina rosmarinifolia had no important effect on oxidant production. However, Santolina rosmarinifolia solutions had a positive effect by increasing the thiols concentration in the serum of the models. The sum of all the effects produced by the administration of Santolina did not show a significant decrease of nitro-oxidative stress. Further experiments including smaller concentrations of Santolina rosmarinifolia will be made. Santolina rosmarinifolia should also be tested as a curative treatment.

Keywords: inflammation, MDA, nitric oxide, santolina rosmarinifolia, thiols, TAR, TOS

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2654 Designing of Tooling Solution for Material Handling in Highly Automated Manufacturing System

Authors: Muhammad Umair, Yuri Nikolaev, Denis Artemov, Ighor Uzhinsky

Abstract:

A flexible manufacturing system is an integral part of a smart factory of industry 4.0 in which every machine is interconnected and works autonomously. Robots are in the process of replacing humans in every industrial sector. As the cyber-physical-system (CPS) and artificial intelligence (AI) are advancing, the manufacturing industry is getting more dependent on computers than human brains. This modernization has boosted the production with high quality and accuracy and shifted from classic production to smart manufacturing systems. However, material handling for such automated productions is a challenge and needs to be addressed with the best possible solution. Conventional clamping systems are designed for manual work and not suitable for highly automated production systems. Researchers and engineers are trying to find the most economical solution for loading/unloading and transportation workpieces from a warehouse to a machine shop for machining operations and back to the warehouse without human involvement. This work aims to propose an advanced multi-shape tooling solution for highly automated manufacturing systems. The currently obtained result shows that it could function well with automated guided vehicles (AGVs) and modern conveyor belts. The proposed solution is following requirements to be automation-friendly, universal for different part geometry and production operations. We used a bottom-up approach in this work, starting with studying different case scenarios and their limitations and finishing with the general solution.

Keywords: artificial intelligence, cyber physics system, Industry 4.0, material handling, smart factory, flexible manufacturing system

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2653 Effect of Nitrogen-Based Cryotherapy on the Calf Muscle Spasticity in Stroke Patients

Authors: Engi E. I. Sarhan, Usama M. Rashad, Ibrahim M. I. Hamoda, Mohammed K. Mohamed

Abstract:

Background: This study aimed to know the effect of nitrogen-based cryotherapy on the spasticity of calf muscle in stroke patients. Patients were selected from the outpatient clinic of Neurology, Al-Mansoura general hospital, Al-Mansoura University. Subjects and methods: Thirty Stroke Patients of both sexes ranged from 45 to 60 years old were divided randomly into two equal groups, a study group (A) received a nitrogen-based cryotherapy, a selective physical therapy program and ankle foot orthosis (AFO), while as patients in control group (B) received the same program and AFO only. The treatment duration was three times per week for four weeks for both groups. We assessed spasticity of calf muscle before and after treatment subjectively using modified Ashworth scale (MAS) and objectively via measuring H / M ratio on electromyography machine. We also assessed ankle dorsiflexion ROM objectively using two dimensions motion analysis (2D). Results: After treatment, there was a highly significant improvement in the study group compared to the control group regarding the score of MAS, no significant difference in the study group compared to the control group regarding the readings of H / M ratio, highly significant improvement in the study group compared to the control group regarding the 2D motion analysis findings. Conclusion: This modality considers effective in reducing spasticity in the calf muscle and improving ankle dorsiflexion of the affected limb.

Keywords: ankle foot orthosis, nitrogen-based cryotherapy, stroke, spasticity

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2652 The Determination of Stress Experienced by Nursing Undergraduate Students during Their Education

Authors: Gülden Küçükakça, Şefika Dilek Güven, Rahşan Kolutek, Seçil Taylan

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Objective: Nursing students face with stress factors affecting academic performance and quality of life as from first moments of their educational life. Stress causes health problems in students such as physical, psycho-social, and behavioral disorders and might damage formation of professional identity by decreasing efficiency of education. In addition to determination of stress experienced by nursing students during their education, it was aimed to help review theoretical and clinical education settings for bringing stress of nursing students into positive level and to raise awareness of educators concerning their own professional behaviors. Methods: The study was conducted with 315 students studying at nursing department of Semra and Vefa Küçük Health High School, Nevşehir Hacı Bektaş Veli University in the academic year of 2015-2016 and agreed to participate in the study. “Personal Information Form” prepared by the researchers upon the literature review and “Nursing Education Stress Scale (NESS)” were used in this study. Data were assessed with analysis of variance and correlation analysis. Results: Mean NESS Scale score of the nursing students was estimated to be 66.46±16.08 points. Conclusions: As a result of this study, stress level experienced by nursing undergraduate students during their education was determined to be high. In accordance with this result, it can be recommended to determine sources of stress experienced by nursing undergraduate students during their education and to develop approaches to eliminate these stress sources.

Keywords: stress, nursing education, nursing student, nursing education stress

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2651 Solanum Nigrum Show Anti-Obesity Effects on High Fat Diet Fed Sprague Dawley Rats

Authors: Kathryn Nderitu, Atunga Nyachieo, Ezekiel Mecha

Abstract:

Introduction: Solanum nigrum , also known as black nightshade, biosynthesizes various phytochemical compounds with various pharmacological activities, including treating cardiovascular diseases and type 2 diabetes, among others. Materials and Methods: To assess the anti-obesity effects of Solanum nigrum using high-fat-fed diet rats, Sprague Dawley male rats (n = 35) of weights 160–180 g were assigned randomly into seven groups comprising n = 5 rats each. Each group was fed for 11 weeks as follows: normal group (normal chow rat feed); high-fat diet control (HFD); HFD and standard drug (Orlistat 30 mg/kg bw); HFD and methanolic extract 150 mg/kgbw; HFD and methanolic extract 300 mg/kgbw; HFD and dichloromethane extract 150 mg/kgbw; HFD and dichloromethane extract 300 mg/kgbw. Body mass index and food intake were monitored per week, and an oral glucose tolerance test was measured in weeks 5 and 10. Lipid profiles, liver function tests, adipose tissue, liver weights, and phytochemical analysis of Solanum nigrum were later carried out. Results: High-fat diet control group rats exhibited a significant increase in body mass index (BMI), while rats administered with leaf extracts of Solanum nigrum showed a reduction in BMI. Both low doses of dichloromethane (150 mg/kgbw) and high doses of methanol extracts (300 mg/kgbw) showed a better reduction in BMI than the other treatment groups. A significant decrease (p <0.05) in low-density lipoprotein-cholesterol, triglycerides, and cholesterol was observed among the rats administered with Solanum nigrum extracts compared to those of HFD control. Moreover, the HFD control group significantly increased liver and adipose tissue weights compared to other treatment groups (p<0.05). Solanum nigrum also decreased glycemic levels and normalized the hepatic enzymes of HFD control. However, food intake among the groups showed no significant difference (p>0.05). Qualitative analysis of Solanum nigrum leaf extracts indicated the presence of various bioactive compounds associated with anti-obesity. Conclusion: These results validate the use of Solanum nigrum in controlling obesity.

Keywords: solanum nigrum, High fat diet, phytocompounds, obesity

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2650 Depression and Associated Factors among Adolescent Females in Riyadh, Kingdom of Saudi Arabia: A Cross‑Sectional Study

Authors: Hafsa Raheel

Abstract:

Background: Adolescents who suffer from depression early in life, have an increase in suicidal tendency, anxiety, conduct disorders, substance abuse, and continue to be depressed, later on in life. This study was conducted to identify the prevalence and correlates of depression among adolescent girls in Riyadh city in order to carry out early intervention. Methods: A cross‑sectional, school‑based survey was conducted among 1028 adolescent girls aged 15–19 years in secondary schools of Riyadh city. Riyadh was divided into clusters and within each cluster, both public and private schools were enrolled. From the selected schools students from grade 10–12 were surveyed. Survey was conducted using a structured questionnaire including the beck depression inventory‑II, and questions exploring the correlates of depression. Results: About 30% of participants were found to be depressed. Depression was more prevalent among female adolescents whose household income was inferior to 12,000 Saudi Riyal/month (odds ratio [OR] 2.17, confidence interval [CI] 0.97–6.84), did not have a good relationship with peers and family members (OR 4.63, CI 2.56–8.41), lived with single parent or alone (OR 1.77, CI 0.97–3.23), had been emotionally abused (OR 3.45, CI 2.56–8.41), and those who had been subjected to physical violence at least once (OR 3.34, CI 1.89–5.91). Conclusions: Strategies need to be developed to identify early signs and symptoms of depression among Saudi female adolescents. Training can be given to groups of students to help their peers, and also to the teachers to identify, and help students identify early signs of depression and provide them with better‑coping strategies to combat progression of depression and anxiety among such adolescents.

Keywords: adolescents, depression, Saudi Arabia, mental health

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2649 Distributed Cost-Based Scheduling in Cloud Computing Environment

Authors: Rupali, Anil Kumar Jaiswal

Abstract:

Cloud computing can be defined as one of the prominent technologies that lets a user change, configure and access the services online. it can be said that this is a prototype of computing that helps in saving cost and time of a user practically the use of cloud computing can be found in various fields like education, health, banking etc.  Cloud computing is an internet dependent technology thus it is the major responsibility of Cloud Service Providers(CSPs) to care of data stored by user at data centers. Scheduling in cloud computing environment plays a vital role as to achieve maximum utilization and user satisfaction cloud providers need to schedule resources effectively.  Job scheduling for cloud computing is analyzed in the following work. To complete, recreate the task calculation, and conveyed scheduling methods CloudSim3.0.3 is utilized. This research work discusses the job scheduling for circulated processing condition also by exploring on this issue we find it works with minimum time and less cost. In this work two load balancing techniques have been employed: ‘Throttled stack adjustment policy’ and ‘Active VM load balancing policy’ with two brokerage services ‘Advanced Response Time’ and ‘Reconfigure Dynamically’ to evaluate the VM_Cost, DC_Cost, Response Time, and Data Processing Time. The proposed techniques are compared with Round Robin scheduling policy.

Keywords: physical machines, virtual machines, support for repetition, self-healing, highly scalable programming model

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2648 Nanoemulsion Formulation of Ethanolic Extracts of Propolis and Its Antioxidant Activity

Authors: Rachmat Mauludin, Dita Sasri Primaviri, Irda Fidrianny

Abstract:

Propolis contains several antioxidant compounds which can be used in topical application to protect skin against free radical, prevent skin cancer and skin aging. Previous study showed that 70% ethanolic extract of propolis (EEP) provided the greatest antioxidant activity. Since EEP has very small solubility in water, the extract was prepared in nanoemulsion (NE). Nanoemulsion is chosen as cosmetic dosage forms according to its properties namely to decrease the risk of skin’s irritation, increase penetration, prolong its time to remain in our skin, and improve stability. Propolis was extracted using reflux methods and concentrated using rotavapor. EEP was characterized with several tests such as phytochemical screening, density, and antioxidant activity using DPPH method. Optimation of total surfactant, co-surfactant, oil, and amount of EEP that can be included in NE were required to get the best NE formulation. The evaluations included to organoleptic observation, globul size, polydispersity index, morphology using TEM, viscosity, pH, centrifuge, stability, Freeze and Thaw test, radical scavenging activity using DPPH method, and primary irritation test. The yield extracts was 11.12% from raw propolis contained of steroid/triterpenoid, flavonoid, and saponin based on phytochemical screening. EEP had the value of DPPH scavenging activity 61.14% and IC50 0.41629 ppm. The best NE formulation consisted of 26.25% Kolliphor RH40; 8.75% glycerine; 5% rice bran oil; and 3% EEP. NE was transparant, had globul size of 21.9 nm; polydispersity index of 0.338; and pH of 5.67. Based on TEM morphology, NE was almost spherical and has particle size below 50 nm. NE propolis revealed to be physically stable after stability test within 63 days at 25oC, centrifuged for 30 mins at 13.000 rpm, and passed 6 cycles of Freeze and Thaw test without separated. NE propolis reduced 58% of free radical DPPH similar to antioxidant activity of the original extracts. Antioxidant activity of NE propolis is relatively stable after stored for 6 weeks. NE Propolis was proven to be safe by primary irritation test with the value of primary irritation index (OECD) was 0. The best formulation for NE propolis contained of 26.25% Kolliphor RH40; 8.75% glycerine; 5% rice bran oil; and 3% EEP with globul size of 21.9 nm and polydispersity index of 0.338. NE propolis was stable and had antioxidant activity similar to EEP.

Keywords: propolis, antioxidant, nanoemulsion, irritation test

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2647 Development of a Matlab® Program for the Bi-Dimensional Truss Analysis Using the Stiffness Matrix Method

Authors: Angel G. De Leon Hernandez

Abstract:

A structure is defined as a physical system or, in certain cases, an arrangement of connected elements, capable of bearing certain loads. The structures are presented in every part of the daily life, e.g., in the designing of buildings, vehicles and mechanisms. The main goal of a structure designer is to develop a secure, aesthetic and maintainable system, considering the constraint imposed to every case. With the advances in the technology during the last decades, the capabilities of solving engineering problems have increased enormously. Nowadays the computers, play a critical roll in the structural analysis, pitifully, for university students the vast majority of these software are inaccessible due to the high complexity and cost they represent, even when the software manufacturers offer student versions. This is exactly the reason why the idea of developing a more reachable and easy-to-use computing tool. This program is designed as a tool for the university students enrolled in courser related to the structures analysis and designs, as a complementary instrument to achieve a better understanding of this area and to avoid all the tedious calculations. Also, the program can be useful for graduated engineers in the field of structural design and analysis. A graphical user interphase is included in the program to make it even simpler to operate it and understand the information requested and the obtained results. In the present document are included the theoretical basics in which the program is based to solve the structural analysis, the logical path followed in order to develop the program, the theoretical results, a discussion about the results and the validation of those results.

Keywords: stiffness matrix method, structural analysis, Matlab® applications, programming

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2646 Hybrid Adaptive Modeling to Enhance Robustness of Real-Time Optimization

Authors: Hussain Syed Asad, Richard Kwok Kit Yuen, Gongsheng Huang

Abstract:

Real-time optimization has been considered an effective approach for improving energy efficient operation of heating, ventilation, and air-conditioning (HVAC) systems. In model-based real-time optimization, model mismatches cannot be avoided. When model mismatches are significant, the performance of the real-time optimization will be impaired and hence the expected energy saving will be reduced. In this paper, the model mismatches for chiller plant on real-time optimization are considered. In the real-time optimization of the chiller plant, simplified semi-physical or grey box model of chiller is always used, which should be identified using available operation data. To overcome the model mismatches associated with the chiller model, hybrid Genetic Algorithms (HGAs) method is used for online real-time training of the chiller model. HGAs combines Genetic Algorithms (GAs) method (for global search) and traditional optimization method (i.e. faster and more efficient for local search) to avoid conventional hit and trial process of GAs. The identification of model parameters is synthesized as an optimization problem; and the objective function is the Least Square Error between the output from the model and the actual output from the chiller plant. A case study is used to illustrate the implementation of the proposed method. It has been shown that the proposed approach is able to provide reliability in decision making, enhance the robustness of the real-time optimization strategy and improve on energy performance.

Keywords: energy performance, hybrid adaptive modeling, hybrid genetic algorithms, real-time optimization, heating, ventilation, and air-conditioning

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2645 A Systematic Review of Quality of Life in Older Adults with Sensory Impairments

Authors: Ya-Chuan Tseng, Hsin-Yi Liu, Meei-Fang Lou, Guey-Shiun Huang

Abstract:

Purpose: Sensory impairments are common in older adults. Hearing and visual impairments affect their physical and mental health and quality of life (QOL) adversely. However, systematic reviews of the relationship between hearing impairment, visual impairment, dual sensory impairment and quality of life are scarce. The purpose of this systematic review was to determine the relationship between hearing impairment, visual impairment, dual sensory impairment and quality of life. Methods: Searches of EMBASE, PubMed, CINAHL, MEDLINE, Cochrane Library and Airiti Library were conducted between January 2006 and December 2017 using the keywords ‘quality of life,’ ‘life satisfaction,’ ‘well-being,’ ‘hearing impairment’ and ‘visual impairment’ Two authors independently assessed methodologic quality using a modified Downs and Black tool. Data were extracted by the first author and then cross-checked by the second author. Results: Twenty-three studies consisting mostly of community-dwelling older adults were included in our review. Sensory impairment was found to be in significant association with quality of life, with an increase in hearing impairment or visual impairment severity resulting in a lower quality of life. Quality of life for dual sensory impairment was worse than for hearing impairment or visual impairment individually. Conclusions: A significant association was confirmed between hearing impairment, visual impairment, dual sensory impairment and quality of life. Our review can be used to enhance health care personnel’s understanding of sensory impairment in older adults and enable healthcare personnel to actively assess older adults’ sensory functions so that they can help alleviate the negative impact of sensory impairments on QOL in older adults.

Keywords: nursing, older adults, quality of life, systematic review, hearing impairment, visual impairment

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2644 Assessing the Effect of Waste-based Geopolymer on Asphalt Binders

Authors: Amani A. Saleh, Maram M. Saudy, Mohamed N. AbouZeid

Abstract:

Asphalt cement concrete is a very commonly used material in the construction of roads. It has many advantages, such as being easy to use as well as providing high user satisfaction in terms of comfortability and safety on the road. However, there are some problems that come with asphalt cement concrete, such as its high carbon footprint, which makes it environmentally unfriendly. In addition, pavements require frequent maintenance, which could be very costly and uneconomic. The aim of this research is to study the effect of mixing waste-based geopolymers with asphalt binders. Geopolymer mixes were prepared by combining alumino-silicate sources such as fly ash, silica fumes, and metakaolin with alkali activators. The purpose of mixing geopolymers with the asphalt binder is to enhance the rheological and microstructural properties of asphalt. This was done through two phases, where the first phase was developing an optimum mix design of the geopolymer additive itself. The following phase was testing the geopolymer-modified asphalt binder after the addition of the optimum geopolymer mix design to it. The testing of the modified binder is performed according to the Superpave testing procedures, which include the dynamic shear rheometer to measure parameters such as rutting and fatigue cracking, and the rotational viscometer to measure workability. In addition, the microstructural properties of the modified binder is studied using the environmental scanning electron microscopy test (ESEM). In the testing phase, the aim is to observe whether the addition of different geopolymer percentages to the asphalt binder will enhance the properties of the binder and yield desirable results. Furthermore, the tests on the geopolymer-modified binder were carried out at fixed time intervals, therefore, the curing time was the main parameter being tested in this research. It was observed that the addition of geopolymers to asphalt binder has shown an increased performance of asphalt binder with time. It is worth mentioning that carbon emissions are expected to be reduced since geopolymers are environmentally friendly materials that minimize carbon emissions and lead to a more sustainable environment. Additionally, the use of industrial by-products such as fly ash and silica fumes is beneficial in the sense that they are recycled into producing geopolymers instead of being accumulated in landfills and therefore wasting space.

Keywords: geopolymer, rutting, superpave, fatigue cracking, sustainability, waste

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2643 Working With Accessibility in Latvian Contemporary Art: Research, Barriers, and Implementation From a Curator’s and Production Manager’s Perspective

Authors: Agnese Zviedre

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In 2010 Latvia ratified the United Nations Convention on the Rights of Persons with Disabilities, which states that the state will recognize the importance of accessibility to the physical, social, and cultural environment. Nevertheless, accessibility of art and culture in Latvia has become a focal point only since 2020. A study on the impact of cultural consumption and participation done by the Latvian Academy of Culture and the research center “SKDS” results show that art and cultural institutions lack knowledge and understanding of needs and required accessibility measures for people with disabilities to participate in cultural and art events. At the same time, even if art institutions want to create accessible events for people with diverse bodies and minds, many barriers exist, such as budget, lack of time, and lack of knowledge. Even though disability is still largely invisible in the public space, due to recent public campaigns and awareness of the need for accessibility, the media and society are starting to speak about disability as a social issue, not a medical one. Thus, this paper focuses on the first-hand experience of implementing different Western accessibility guidelines and working with communities as a production manager for the multidisciplinary exhibition project “Invisible Lives” in Riga and curator of the education program of Riga Photography Biennial’s 2022 Central Event - Exhibition “Screen Age III: Still Life”. Analyzing two events from the Disability studies perspective, this paper focuses on working with existing knowledge and budget to achieve accessibility.

Keywords: accessibility, contemporary art, curatorial practices, disability studies

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2642 Selection of Soil Quality Indicators of Rice Cropping Systems Using Minimum Data Set Influenced by Imbalanced Fertilization

Authors: Theresa K., Shanmugasundaram R., Kennedy J. S.

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Nutrient supplements are indispensable for raising crops and to reap determining productivity. The nutrient imbalance between replenishment and crop uptake is attempted through the input of inorganic fertilizers. Excessive dumping of inorganic nutrients in soil cause stagnant and decline in yield. Imbalanced N-P-K ratio in the soil exacerbates and agitates the soil ecosystems. The study evaluated the fertilization practices of conventional (CFs), organic and Integrated Nutrient Management system (INM) on soil quality using key indicators and soil quality indices. Twelve rice farming fields of which, ten fields were having conventional cultivation practices, one field each was organic farming based and INM based cultivated under monocropping sequence in the Thondamuthur block of Coimbatore district were fixed and properties viz., physical, chemical and biological were studied for four cropping seasons to determine soil quality index (SQI). SQI was computed for conventional, organic and INM fields. Comparing conventional farming (CF) with organic and INM, CF was recorded with a lower soil quality index. While in organic and INM fields, the higher SQI value of 0.99 and 0.88 respectively were registered. CF₄ received with a super-optimal dose of N (250%) showed a lesser SQI value (0.573) as well as the yield (3.20 t ha⁻¹) and the CF6 which received 125 % N recorded the highest SQI (0.715) and yield (6.20 t ha⁻¹). Likewise, most of the CFs received higher N beyond the level of 125 % except CF₃ and CF₉, which recorded lower yields. CFs which received super-optimal P in the order of CF₆&CF₇>CF₁&CF₁₀ recorded lesser yields except for CF₆. Super-optimal K application also recorded lesser yield in CF₄, CF₇ and CF₉.

Keywords: rice cropping system, soil quality indicators, imbalanced fertilization, yield

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2641 Two-Dimensional Observation of Oil Displacement by Water in a Petroleum Reservoir through Numerical Simulation and Application to a Petroleum Reservoir

Authors: Ahmad Fahim Nasiry, Shigeo Honma

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We examine two-dimensional oil displacement by water in a petroleum reservoir. The pore fluid is immiscible, and the porous media is homogenous and isotropic in the horizontal direction. Buckley-Leverett theory and a combination of Laplacian and Darcy’s law are used to study the fluid flow through porous media, and the Laplacian that defines the dispersion and diffusion of fluid in the sand using heavy oil is discussed. The reservoir is homogenous in the horizontal direction, as expressed by the partial differential equation. Two main factors which are observed are the water saturation and pressure distribution in the reservoir, and they are evaluated for predicting oil recovery in two dimensions by a physical and mathematical simulation model. We review the numerical simulation that solves difficult partial differential reservoir equations. Based on the numerical simulations, the saturation and pressure equations are calculated by the iterative alternating direction implicit method and the iterative alternating direction explicit method, respectively, according to the finite difference assumption. However, to understand the displacement of oil by water and the amount of water dispersion in the reservoir better, an interpolated contour line of the water distribution of the five-spot pattern, that provides an approximate solution which agrees well with the experimental results, is also presented. Finally, a computer program is developed to calculate the equation for pressure and water saturation and to draw the pressure contour line and water distribution contour line for the reservoir.

Keywords: numerical simulation, immiscible, finite difference, IADI, IDE, waterflooding

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2640 Preparation and Properties of Self-Healing Polyurethanes Utilizing the Host-Guest Interaction between Cyclodextrin and Adamantane Moieties

Authors: Kaito Sugane, Mitsuhiro Shibata

Abstract:

Self-healing polymers have attracted attention because their physical damage and cracks can be effectively repaired, thereby extending the lifetime of the materials. Self-healing polymers using host-guest interaction have the advantage that they are quickly repaired under mild temperature conditions when compared with self-healing polymer using dynamic covalent bonds such as Diels-Alder (DA)/retro-DA and disulfide metathesis reactions. Especially, it is known that hydrogels utilizing the host-guest interaction between cyclodextrin and various guest molecules are repeatedly self-repaired at room temperature. However, most of the works deal with hydrogels, and little attention has been paid for thermosetting resins as polyurethane, epoxy and unsaturated polyester resins. In this study, polyetherurethane networks (PUN-CD-Ads) incorporating cyclodextrin and adamantane moieties were prepared by the crosslinking reactions of β-cyclodextrin (CD), 1-adamantanol (AdOH), glycerol ethoxylate (GCE) and hexamethylene diisocyanate (HDI), and thermal, mechanical and self-healing properties of the polymer network films were investigated. Our attention was focused on the influences of molar ratio of CD/AdOH, GCE/CD and OH/NCO on the properties. The FT-IR, and gel fraction analysis revealed that the urethanization reaction smoothly progress to form polyurethane networks. When two cut pieces of the films were contacted at the cross-section at room temperature for 30 seconds, the two pieces adhered to produce a self-healed film. Especially, the PUN-CD-Ad prepared at GCE/CD = 5/1, CD/AdOH = 1/1, and OH/NCO = 1/1 film exhibited the highest healing efficiency for tensile strength. Most of the PUN-CD-Ads were successfully self-healed at room temperature.

Keywords: host-guest interaction, network polymer, polyurethane, self-healing

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2639 Acacia mearnsii De Wild-A New Scourge on Cork Oak Forests of El Kala National Park (North-Eastern Algeria)

Authors: Samir Chekchaki, ArifaBeddiar

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Nowadays, more and more species are introduced outside their natural range. If most of them remain difficult, some may adopt a much more dynamic behavior. Indeed, we have witnessed in recent decades, the development of high forests of Acacia mearnsii in El Kala National Park. Introduced indefinitely, this leguminous intended to make money (nitrogen supply for industrial plantations of Eucalyptus), became one of the most invasive and more costly in terms of forest management. It has crossed all barriers: it has acclimatized, naturalized and then expanded through diverse landscapes; entry into competition with native species such as cork oak and altered ecosystem functioning. Therefore, it is interesting to analyze this new threat by relying on plants as bio-indicator for assessing biodiversity at different scales. We have identified the species present in several plots distributed in a range of vegetation types subjected to different degrees of disturbance by using the braun-blanquet method. Fifty-six species have been recorded. They are distributed in 48 genera and 29 families. The analysis of the relative frequency of species correlated with relative abundance clearly shows that the Acacia mearnsii feels marginalized. The ecological analysis of this biological invasion shows that disruption of either natural or anthropogenic origin (fire, prolonged drought, cut) represent the factors that exacerbate invasion by opening invasion windows. The lifting of seeds of Acacia mearnsii lasting physical dormancy (and variable) is ensured by the thermal shock in relation to its heliophilous character.

Keywords: Acacia mearnsii De Wild, El Kala National park, fire, invasive, vegetation

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2638 Experiencing Scarred Body among Thai Women Living with Breast Cancer

Authors: Dusanee Suwankhong, Pranee Liamputtong

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Breast surgery leaves undesirable scars to all women who experienced mastectomy, despite the fact that this could be a principle approach to save one life. This paper explores how Thai women living with breast cancer perceived and experienced a scarred body after breast surgery. In-depth interviews and drawing methods were employed among 20 women diagnosed with breast cancer. The interviewed data were analysed using thematic analysis method. The results showed that all women with breast cancer who underwent breast surgery perceived and experienced scar as a persisting and visible side-effect. This disfigurement appearance presented a negative image of feminine identity and led to emotional burdens among women. They responded to being scarred in different ways relating to their perceptions of body and changes. The older group had less embarrassed feelings towards being scarred comparing to the younger one. All women tried to seek means to cope with such physical impairment and keep balance life related to their condition. For example, they relied on Buddhism practice and tried to heal the keloid using natural products. Scars appeared to be an unpleasant effect for women who underwent breast mastectomy. Nurses and health care professionals in the local health service sectors need to pay close attention to how the women see the scarred body and their experiences of living with the distorted feminine appearance, and to provide sensitive support that meets the needs of these vulnerable women. The suitable supports can reduce the sense of embarrassment and increase their sense of self-confidence about their social femininity.

Keywords: breast surgery, emotional response, qualitative study, scars, Thai women

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2637 Importance of an E-Learning Program in Stress Field for Postgraduate Courses of Doctors

Authors: Ramona-Niculina Jurcau, Ioana-Marieta Jurcau

Abstract:

Background: Preparing in the stress field (SF) is, increasingly, a concern for doctors of different specialties. Aims: The aim was to evaluate the importance of an e-learning program for doctors postgraduate courses, in SF. Methods: Doctors (n= 40 male, 40 female) of different specialties and ages (31-71 years), who attended postgraduate courses in SF, voluntarily responded to a questionnaire that included the following themes: Importance of SF courses for specialty practiced by each respondent doctor (using visual analogue scale, VAS); What SF themes would be indicated as e-learning (EL); Preferred form of SF information assimilation: Classical lectures (CL), EL or a combination of these methods (CL+EL); Which information on the SF course are facilitated by EL model versus CL; In their view which are the first four advantages and the first four disadvantages of EL compared to CL, for SF. Results: To most respondents, the SF courses are important for the specialty they practiced (VAS by an average of 4). The SF themes suggested to be done as EL were: Stress mechanisms; stress factor models for different medical specialties; stress assessment methods; primary stress management methods for different specialties. Preferred form of information assimilation was CL+EL. Aspects of the course facilitated by EL versus CL model: Active reading of theoretical information, with fast access to keywords details; watching documentaries in everyone's favorite order; practice through tests and the rapid control of results. The first four EL advantages, mentioned for SF were: Autonomy in managing the time allocated to the study; saving time for traveling to the venue; the ability to read information in various contexts of time and space; communication with colleagues, in good times for everyone. The first three EL disadvantages, mentioned for SF were: It decreases capabilities for group discussion and mobilization for active participation; EL information accession may depend on electrical source or/and Internet; learning slowdown can appear, by temptation of postponing the implementation. Answering questions was partially influenced by the respondent's age and genre. Conclusions: 1) Post-graduate courses in SF are of interest to doctors of different specialties. 2) The majority of participating doctors preferred EL, but combined with CL (CL+EL). 3) Preference for EL was manifested mainly by young or middle age men doctors. 4) It is important to balance the proper formula for chosen EL, to be the most efficient, interesting, useful and agreeable.

Keywords: stress field, doctors’ postgraduate courses, classical lectures, e-learning lecture

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2636 Green Synthesis of Spinach Derived Carbon Dots for Photocatalytic Generation of Hydrogen from Sulfide Wastewater

Authors: Priya Ruban, Thirunavoukkarasu Manikkannan, Sakthivel Ramasamy

Abstract:

Sulfide is one of the major pollutants of tannery effluent which is mainly generated during the process of unhairing. Recovery of Hydrogen green fuel from sulfide wastewater using photocatalysis is a ‘Cleaner Production Method’, since renewable solar energy is utilized. It has triple advantages of the generation of H2, waste minimization and odor or pollution control. Designing of safe and green photocatalysts and developing suitable solar photoreactor is important for promoting this technology to large-scale application. In this study, green photocatalyst i.e., spinach derived carbon dots (SCDs 5 wt % and 10 wt %)/TiO2 nanocomposite was synthesized for generation of H2 from sulfide wastewater using lab-scale solar photocatalytic reactor. The physical characterization of the synthesized solar light responsive nanocomposites were studied by using DRS UV-Vis, XRD, FTIR and FESEM analysis. The absorption edge of TiO2 nanoparticles is extended to visible region by the incorporation of SCDs, which was used for converting noxious pollutant sulfide into eco-friendly solar fuel H2. The SCDs (10 wt%)-TiO2 nanocomposite exhibits enhanced photocatalytic hydrogen production i.e. ~27 mL of H2 (180 min) from simulated sulfide wastewater under LED visible light irradiation which is higher as compared to SCDs. The enhancement in the photocatalytic generation of H2 is attributed to combining of SCDs which increased the charge mobility. This work may provide new insights to usage of naturally available and cheap materials to design novel nanocomposite as a visible light active photocatalyst for the generation of H2 from sulfide containing wastewater.

Keywords: carbon dots, hydrogen fuel, hydrogen sulfide, photocatalysis, sulfide wastewater

Procedia PDF Downloads 388
2635 Lateral Capacity of Helical-Pile Groups Subjected to Bearing Combined Loads

Authors: Hesham Hamdy Abdelmohsen, Ahmed Shawky Abdul Azizb, Mona Fawzy Aldaghma

Abstract:

Helical piles have earned considerable attention as an effective deep foundation alternative due to their rapid installation process and their dual purpose in compression and tension. These piles find common uses as foundations for structures like solar panels, wind turbines, offshore platforms, and some kinds of retaining walls. These structures usually transfer different combinations of loads to their helical-pile foundations in the form of axial and lateral loads. Extensive research has been conducted to investigate and understand the behavior of these piles under the influence of either axial or lateral loads. However, the impacts of loading patterns that may act on the helical piles as combinations of axial compression and lateral loads still need more efforts of research work. This paper presents the results of an experimental (Lab tests) and numerical (PLAXIS-3D) study performed on vertical helical-pile groups under the action of combined loads as axial compression (bearing loads), acting successively with lateral (horizontal) loads. The study aims to clarify the effects of key factors, like helix location and direction of lateral load, on the lateral capacity of helical-pile groups and, consequently, on group efficiency. Besides the variation of helix location and lateral load direction, three patterns of successive bearing combined loads were considered, in which the axial vertical compression load was either zero, V1 or V2, whereas the lateral horizontal loads were varied under each vertical compression load. The study concluded that the lateral capacity of the helical-pile group is significantly affected by helix location within the length of the pile shaft. The optimal lateral performance is achieved with helices at a depth ratio of H/L = 0.4. Furthermore, groups of rectangular plan distribution exhibit greater lateral capacity if subjected to lateral horizontal load in the direction of its long axis. Additionally, the research emphasizes that the presence of vertical compression loading can enhance the lateral capacity of the group. This enhancement depends on the value of the vertical compression load, lateral load direction, and helix location, which highlights the complex interaction effect of these factors on the efficiency of helical-pile groups.

Keywords: helical piles, experimental, numerical, lateral loading, group efficiency

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2634 The Factors Affecting on Promoting Productivity from Nurses' View

Authors: Mahnaz Sanjari, Sedigheh Salemi, Mohammad Mirzabeigi

Abstract:

Nowadays, the world is facing a crisis of workforce and one of the most striking examples is the shortage of nurses. Nursing workforce productivity is related by various factors such as absenteeism, professional effectiveness and quality care. This cross-sectional study was conducted in 700 nurses who work in government hospitals from 35 hospitals of 9 provinces in Iran. The study was approved by the Nursing Council and was carried out with the authorization of the Research Ethics Committee. The questionnaire included 33 questions and 4 sub categories such as human resource, education and management. The reliability was evaluated by Cronbach's alpha (α=0/85). Statistical analyzes were performed, using SPSS version 16. The result showed that nurses emphasized on "respect to nurse-to-bed ratio" and less importance item was "using less experienced nurse". In addition, another important factor in clinical productivity is "Proper physical structure and amenities","good communication with colleagues" and "having good facilities". Also, "human resources at all levels of standard", "promoting on merit" and "well defined relationship in health system" are another important factors in productivity from nurse` view. The main managerial factor is "justice between employees" and the main educational component of productivity is “updating nursing knowledge”. The results show that more than half of the participants emphasized on the management and educational factors. Productivity as one of the main part of the health care quality leads to appropriate use of human and organizational resources, reduce cost services, and organizational development.

Keywords: productivity, nursing services, workforce, cost services

Procedia PDF Downloads 344
2633 Common Causes of Eye Removal Surgery in Turkish Patients: A Review of 226 Cases

Authors: Titap Yazicioglu

Abstract:

Purpose: To determine the etiological factors responsible for the eye removal surgery and to evaluate our surgical results. Material and Methods: Medical records of 226 patients, who underwent eye removal surgery, were analyzed retrospectively. Demographic information, clinical history, surgical procedure, and histopathological data were all collected. Evisceration surgery was performed under general anesthesia in all patients except tumor cases and one patient with rhino-orbital mucormycosis. The patients were followed for an average of 16.46±10.78 months and checked for the possible complications, cosmesis, and functional results.Results: 144 men, and 82 women,with a mean age of 41.78±22.6 years, were underwent enucleation (n=15) or evisceration (n=211) due to traumatic (n=169) and non-traumatic (n=57) causes. In the traumatic group, 79.8% of 169 patients were injured by penetrating and 14.2% by blunt trauma.3.6% of the patients were injured in a traffic accident, and 2.4% of them were injured by explosives. In the non-traumatic group, 40% of 25 patients had post-traumatic endophthalmitis, 32% had endophthalmitis due to corneal ulceration and melting, and 24% had endophthalmitis after cataract surgery. One patient had panophthalmitis due to rhino-orbital mucormycosis. Another cause in the non-traumatic group was glaucoma, of which 92.3% had neovascular glaucoma, and 8.7% had congenital glaucoma. Of the 14 patients who were enucleated for tumor, 35.7% had retinoblastoma, 14.3% had medulloepithelioma, 42.9% had uveal melanoma, and 7.1% had metastatic tumor from paranasal sinuses.The most common complaint in the follow-up period was discharging, seen in all prosthesis-wearing patients. 13.3% of the patients had itching due to ocular prosthesis. 4.4% of the patients were complaining about deep superior sulcus. 4.4% had pyogenic granuloma, and 17.8% had implant exposure. Conclusion: Etiological factors should be carefully evaluated, and precautions should be taken in order to reduce the devastating effect of the physical loss of the eye.

Keywords: enucleation, evisceration, ocular injury, etiology, frequency

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2632 Nanoindentation Studies of Metallic Cu-CuZr Composites Synthesized by Accumulative Roll Bonding

Authors: Ehsan Alishahi, Chuang Deng

Abstract:

Materials with microstructural heterogeneity have recently attracted dramatic attention in the materials science community. Although most of the metals are identified as crystalline, the new class of amorphous alloys, sometimes are known as metallic glasses (MGs), exhibited remarkable properties, particularly high mechanical strength and elastic limit. The unique properties of MGs led to the wide range of studies in developing and characterizing of new alloys or composites which met the commercial desires. In spite of applicable properties of MGs, commercializing of metallic glasses was limited due to a major drawback, the lack of ductility and sudden brittle failure mode. Hence, crystalline-amorphous (C-A) composites were introduced almost in 2000s as a toughening strategy to improve the ductility of MGs. Despite the considerable progress reported in previous studies, there are still challenges in both synthesis and characterization of metallic C-A composites. In this study, accumulative roll bonding (ARB) was used to synthesize bulk crystalline-amorphous composites starting from crystalline Cu-Zr multilayers. Due to the severe plastic deformation state, new CuZr phases were formed during the rolling process which was reflected in SEM-EDS analysis. EDS elemental analysis showed the variation in the composition of CuZr phases such as 38-62, 50-50 to 68-32 at Cu-Zr % respectively. Moreover, TEM with electron diffraction analysis indicated the presence of both crystalline and amorphous structures for the new formed CuZr phases. In addition to the microstructural analysis, the mechanical properties of the synthesized composites were studied using the nanoindentation technique. Hysitron Nanoindentation instrument was used to conduct nanoindentation tests with cube corner tip. The maximum load of 5000 µN was applied in load control mode to measure the elastic modulus and hardness of different phases. The trend of results indicated three distinct regimes of hardness and elastic modulus including pure Cu, pure Zr, and new formed CuZr phases. More specifically, pure Cu regions showed the lowest values for both nanoindentation hardness and elastic modulus while the CuZr phases take the highest values. Consequently, pure Zr was placed in the intermediate range which is harder than pure Cu but softer than CuZr phases. In overall, it was found that CuZr phases with higher hardness were nucleated during ARB process as a result of mechanical alloying phenomenon.

Keywords: ARB, crystalline-amorphous composites, mechanical alloying, nanoindentation hardness

Procedia PDF Downloads 550
2631 Inequality of Opportunities in the Health of the Adult Population of Russia

Authors: Marina Kartseva, Polina Kuznetsova

Abstract:

In our work, we estimate the contribution of inequality of opportunity to inequality in the health of the Russian population aged 25 to 74 years. The empirical basis of the study is the nationally representative data of the RLMS for 2018. Individual health is measured using a self-reported status on five-point scale. The startconditions are characterized by parental education and place of birth (country, type of settlement). Personal efforts to maintain health include the level of education, smoking status, and physical activity. To understand how start opportunities affect an individual's health, we use the methodology proposed in (Trannoy et al., 2010), which takes into account both direct and indirect (through the influence on efforts) effects. Regression analysis shows that all other things being equal, the starting capabilities of individuals have a significant impact on their health. In particular, parental education has a positive effect on self-reported health. Birth in another country, in another settlement, and in an urban area, on the contrary, reduceself-reported health. This allows to conclude that there exists an unfair inequality in health, namely inequality caused by factors that are independent of a person's own efforts. We estimate the contribution of inequality of opportunity to inequality in health using a nonparametric approach (Checchi, Peragine, 2010; Lazar, 2013). According to the obtained results, the contribution of unfair inequality as 72-74% for the population as a whole, being slightly higher for women (62-74% and 60-69% for men and women, respectively) and for older age (59- 62% and 67-75% for groups 25-44 years old and 45-74 years old, respectively). The obtained estimates are comparable with the results for other countries and indicate the importance of the problem of inequality of opportunities in health in Russia.

Keywords: inequality of opportunity, inequality in health, self-reported health, efforts, health-related lifestyle, Russia, RLMS

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2630 Design and Construction Demeanor of a Very High Embankment Using Geosynthetics

Authors: Mariya Dayana, Budhmal Jain

Abstract:

Kannur International Airport Ltd. (KIAL) is a new Greenfield airport project with airside development on an undulating terrain with an average height of 90m above Mean Sea Level (MSL) and a maximum height of 142m. To accommodate the desired Runway length and Runway End Safety Area (RESA) at both the ends along the proposed alignment, it resulted in 45.5 million cubic meters in cutting and filling. The insufficient availability of land for the construction of free slope embankment at RESA 07 end resulted in the design and construction of Reinforced Soil Slope (RSS) with a maximum slope of 65 degrees. An embankment fill of average 70m height with steep slopes located in high rainfall area is a unique feature of this project. The design and construction was challenging being asymmetrical with curves and bends. The fill was reinforced with high strength Uniaxial geogrids laid perpendicular to the slope. Weld mesh wrapped with coir mat acted as the facia units to protect it against surface failure. Face anchorage were also provided by wrapping the geogrids along the facia units where the slope angle was steeper than 45 degrees. Considering high rainfall received on this table top airport site, extensive drainage system was designed for the high embankment fill. Gabion wall up to 10m height were also designed and constructed along the boundary to accommodate the toe of the RSS fill beside the jeepable track at the base level. The design of RSS fill was done using ReSSA software and verified in PLAXIS 2D modeling. Both slip surface failure and wedge failure cases were considered in static and seismic analysis for local and global failure cases. The site won excavated laterite soil was used as the fill material for the construction. Extensive field and laboratory tests were conducted during the construction of RSS system for quality assurance. This paper represents a case study detailing the design and construction of a very high embankment using geosynthetics for the provision of Runway length and RESA area.

Keywords: airport, embankment, gabion, high strength uniaxial geogrid, kial, laterite soil, plaxis 2d

Procedia PDF Downloads 162
2629 Robot Technology Impact on Dyslexic Students’ English Learning

Authors: Khaled Hamdan, Abid Amorri, Fatima Hamdan

Abstract:

Involving students in English language learning process and achieving an adequate English language proficiency in the target language can be a great challenge for both teachers and students. This can prove even a far greater challenge to engage students with special needs (Dyslexia) if they have physical impairment and inadequate mastery of basic communicative language competence/proficiency in the target language. From this perspective, technology like robots can probably be used to enhance learning process for the special needs students who have extensive communication needs, who face continuous struggle to interact with their peers and teachers and meet academic requirements. Robots, precisely NAO, can probably provide them with the perfect opportunity to practice social and communication skills, and meet their English academic requirements. This research paper aims to identify to what extent robots can be used to improve students’ social interaction and communication skills and to understand the potential for robotics-based education in motivating and engaging UAEU dyslexic students to meet university requirements. To reach this end, the paper will explore several factors that come into play – Motion Level-involving cognitive activities, Interaction Level-involving language processing, Behavior Level -establishing a close relationship with the robot and Appraisal Level- focusing on dyslexia students’ achievement in the target language.

Keywords: dyslexia, robot technology, motion, interaction, behavior and appraisal levels, social and communication skills

Procedia PDF Downloads 372
2628 Absorption Kinetic and Tensile Mechanical Properties of Swollen Elastomer/Carbon Black Nanocomposites using Typical Solvents

Authors: F. Elhaouzi, H. Lahlali, M. Zaghrioui, I. El Aboudi A. BelfKira, A. Mdarhri

Abstract:

The effect of physico chemical properties of solvents on the transport process and mechanical properties in elastomeric nano composite materials is reported. The investigated samples are formed by a semi-crystalline ethylene-co-butyl acrylate polymer filled with hard spherical carbon black (CB) nano particles. The swelling behavior was studied by immersion the dried samples in selected solvents at room temperature during 2 days. For this purpose, two chemical compounds methyl derivatives of aromatic hydrocarbons of benzene, i.e. toluene and xylene, are used to search for the mass and molar volume dependence on the absorption kinetics. Mass gain relative to the mass of dry material at specific times was recorded to probe the absorption kinetics. The transport of solvent molecules in these filled elastomeric composites is following a Fickian diffusion mechanism. Additionally, the swelling ratio and diffusivity coefficient deduced from the Fickian law are found to decrease with the CB concentration. These results indicate that the CB nano particles increase the effective path length for diffusion and consequently limit the absorption of the solvent by occupation free volumes in the material. According to physico chemical properties of the two used solvents, it is found that the diffusion is more important for the toluene molecules solvent due to their low values of the molecular weight and volume molar compared to those for the xylene. Differential Scanning Calorimetry (DSC) and X-ray photo electron (XPS) were also used to probe the eventual change in the chemical composition for the swollen samples. Mechanically speaking, the stress-strain curves of uniaxial tensile tests pre- and post- swelling highlight a remarkably decrease of the strength and elongation at break of the swollen samples. This behavior can be attributed to the decrease of the load transfer density between the matrix and the CB in the presence of the solvent. We believe that the results reported in this experimental investigation can be useful for some demanding applications e.g. tires, sealing rubber.

Keywords: nanocomposite, absorption kinetics, mechanical behavior, diffusion, modelling, XPS, DSC

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2627 Development of Methods for Plastic Injection Mold Weight Reduction

Authors: Bita Mohajernia, R. J. Urbanic

Abstract:

Mold making techniques have focused on meeting the customers’ functional and process requirements; however, today, molds are increasing in size and sophistication, and are difficult to manufacture, transport, and set up due to their size and mass. Presently, mold weight saving techniques focus on pockets to reduce the mass of the mold, but the overall size is still large, which introduces costs related to the stock material purchase, processing time for process planning, machining and validation, and excess waste materials. Reducing the overall size of the mold is desirable for many reasons, but the functional requirements, tool life, and durability cannot be compromised in the process. It is proposed to use Finite Element Analysis simulation tools to model the forces, and pressures to determine where the material can be removed. The potential results of this project will reduce manufacturing costs. In this study, a light weight structure is defined by an optimal distribution of material to carry external loads. The optimization objective of this research is to determine methods to provide the optimum layout for the mold structure. The topology optimization method is utilized to improve structural stiffness while decreasing the weight using the OptiStruct software. The optimized CAD model is compared with the primary geometry of the mold from the NX software. Results of optimization show an 8% weight reduction while the actual performance of the optimized structure, validated by physical testing, is similar to the original structure.

Keywords: finite element analysis, plastic injection molding, topology optimization, weight reduction

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2626 An Evaluation of the Effectiveness of the Juvenile Justice in Rehabilitating the Youth in South Africa

Authors: Leah Gwatimba, Nanga Raymond Raselekoane

Abstract:

The incidences of youth who engage in unlawful or criminal activities are of great concern for the criminal justice system and government in South Africa. In terms of the juvenile justice system in South Africa, under-age youth who have been found guilty and sentenced to serve a jail term cannot be sent to the same detention facility as adults. The juvenile justice system is meant to protect young offenders from physical, emotional and mental exploitation by adult prisoners. Under-age young offenders should be assisted and exposed to educational, entrepreneurial and behavioral programmes that can equip them with the much needed skills that will turn them into law-abiding and economically productive citizens. The aim of this study was to evaluate the effectiveness of the justice system in South Africa in the rehabilitation young offenders. A qualitative method was used. The study used the non-probability purposive sampling to select the respondents. In-depth interviews, focus groups, observation and thematic coding were used to collect and analyse the data respectively. The study population consisted of social workers and offending youth. The sample comprised of 16 respondents (i.e. 4 social workers and twelve offending youth (6 males and 6 females). The study indicated that there is worrying recurrence of the anti-social behavior by some of the young offenders. According to this study, the effectiveness of the juvenile justice system in the rehabilitation of the offending youth can be achieved by paying serious attention to follow-up services, participation of families of the offending youth in the diversion programmes and by improving the socio-economic conditions in the homes and communities of the offending youth.

Keywords: juvenile delinquent, juvenile justice system, diversion programmes, rehabilitation, restorative justice

Procedia PDF Downloads 322