Search results for: mechanism properties
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11548

Search results for: mechanism properties

2878 Characterization of Aquifer Systems and Identification of Potential Groundwater Recharge Zones Using Geospatial Data and Arc GIS in Kagandi Water Supply System Well Field

Authors: Aijuka Nicholas

Abstract:

A research study was undertaken to characterize the aquifers and identify the potential groundwater recharge zones in the Kagandi district. Quantitative characterization of hydraulic conductivities of aquifers is of fundamental importance to the study of groundwater flow and contaminant transport in aquifers. A conditional approach is used to represent the spatial variability of hydraulic conductivity. Briefly, it involves using qualitative and quantitative geologic borehole-log data to generate a three-dimensional (3D) hydraulic conductivity distribution, which is then adjusted through calibration of a 3D groundwater flow model using pumping-test data and historic hydraulic data. The approach consists of several steps. The study area was divided into five sub-watersheds on the basis of artificial drainage divides. A digital terrain model (DTM) was developed using Arc GIS to determine the general drainage pattern of Kagandi watershed. Hydrologic characterization involved the determination of the various hydraulic properties of the aquifers. Potential groundwater recharge zones were identified by integrating various thematic maps pertaining to the digital elevation model, land use, and drainage pattern in Arc GIS and Sufer golden software. The study demonstrates the potential of GIS in delineating groundwater recharge zones and that the developed methodology will be applicable to other watersheds in Uganda.

Keywords: aquifers, Arc GIS, groundwater recharge, recharge zones

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2877 The Role of the Elastic Foundation Having Nonlinear Stiffness Properties in the Vibration of Structures

Authors: E. Feulefack Songong, A. Zingoni

Abstract:

A vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. Although vibrations can be linear or nonlinear depending on the basic components of the system, the interest is mostly pointed towards nonlinear vibrations. This is because most structures around us are to some extent nonlinear and also because we need more accurate values in an analysis. The goal of this research is the integration of nonlinearities in the development and validation of structural models and to ameliorate the resistance of structures when subjected to loads. Although there exist many types of nonlinearities, this thesis will mostly focus on the vibration of free and undamped systems incorporating nonlinearity due to stiffness. Nonlinear stiffness has been a concern to many engineers in general and Civil engineers in particular because it is an important factor that can bring a good modification and amelioration to the response of structures when subjected to loads. The analysis of systems will be done analytically and then numerically to validate the analytical results. We will first show the benefit and importance of stiffness nonlinearity when it is implemented in the structure. Secondly, We will show how its integration in the structure can improve not only the structure’s performance but also its response when subjected to loads. The results of this study will be valuable to practicing engineers as well as industry practitioners in developing better designs and tools for their structures and mechanical devices. They will also serve to engineers to design lighter and stronger structures and to give good predictions as for the behavior of structures when subjected to external loads.

Keywords: elastic foundation, nonlinear, plates, stiffness, structures, vibration

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2876 Methods of Variance Estimation in Two-Phase Sampling

Authors: Raghunath Arnab

Abstract:

The two-phase sampling which is also known as double sampling was introduced in 1938. In two-phase sampling, samples are selected in phases. In the first phase, a relatively large sample of size is selected by some suitable sampling design and only information on the auxiliary variable is collected. During the second phase, a sample of size is selected either from, the sample selected in the first phase or from the entire population by using a suitable sampling design and information regarding the study and auxiliary variable is collected. Evidently, two phase sampling is useful if the auxiliary information is relatively easy and cheaper to collect than the study variable as well as if the strength of the relationship between the variables and is high. If the sample is selected in more than two phases, the resulting sampling design is called a multi-phase sampling. In this article we will consider how one can use data collected at the first phase sampling at the stages of estimation of the parameter, stratification, selection of sample and their combinations in the second phase in a unified setup applicable to any sampling design and wider classes of estimators. The problem of the estimation of variance will also be considered. The variance of estimator is essential for estimating precision of the survey estimates, calculation of confidence intervals, determination of the optimal sample sizes and for testing of hypotheses amongst others. Although, the variance is a non-negative quantity but its estimators may not be non-negative. If the estimator of variance is negative, then it cannot be used for estimation of confidence intervals, testing of hypothesis or measure of sampling error. The non-negativity properties of the variance estimators will also be studied in details.

Keywords: auxiliary information, two-phase sampling, varying probability sampling, unbiased estimators

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2875 Using Flow Line Modelling, Remote Sensing for Reconstructing Glacier Volume Loss Model for Athabasca Glacier, Canadian Rockies

Authors: Rituparna Nath, Shawn J. Marshall

Abstract:

Glaciers are one of the main sensitive climatic indicators, as they respond strongly to small climatic shifts. We develop a flow line model of glacier dynamics to simulate the past and future extent of glaciers in the Canadian Rocky Mountains, with the aim of coupling this model within larger scale regional climate models of glacier response to climate change. This paper will focus on glacier-climate modeling and reconstructions of glacier volume from the Little Ice Age (LIA) to present for Athabasca Glacier, Alberta, Canada. Glacier thickness, volume and mass change will be constructed using flow line modelling and examination of different climate scenarios that are able to give good reconstructions of LIA ice extent. With the availability of SPOT 5 imagery, Digital elevation models and GIS Arc Hydro tool, ice catchment properties-glacier width and LIA moraines have been extracted using automated procedures. Simulation of glacier mass change will inform estimates of meltwater run off over the historical period and model calibration from the LIA reconstruction will aid in future projections of the effects of climate change on glacier recession. Furthermore, the model developed will be effective for further future studies with ensembles of glaciers.

Keywords: flow line modeling, Athabasca Glacier, glacier mass balance, Remote Sensing, Arc hydro tool, little ice age

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2874 Sources of Precipitation and Hydrograph Components of the Sutri Dhaka Glacier, Western Himalaya

Authors: Ajit Singh, Waliur Rahaman, Parmanand Sharma, Laluraj C. M., Lavkush Patel, Bhanu Pratap, Vinay Kumar Gaddam, Meloth Thamban

Abstract:

The Himalayan glaciers are the potential source of perennial water supply to Asia’s major river systems like the Ganga, Brahmaputra and the Indus. In order to improve our understanding about the source of precipitation and hydrograph components in the interior Himalayan glaciers, it is important to decipher the sources of moisture and their contribution to the glaciers in this river system. In doing so, we conducted an extensive pilot study in a Sutri Dhaka glacier, western Himalaya during 2014-15. To determine the moisture sources, rain, surface snow, ice, and stream meltwater samples were collected and analyzed for stable oxygen (δ¹⁸O) and hydrogen (δD) isotopes. A two-component hydrograph separation was performed for the glacier stream using these isotopes assuming the contribution of rain, groundwater and spring water contribution is negligible based on field studies and available literature. To validate the results obtained from hydrograph separation using above method, snow and ice melt ablation were measured using a network of bamboo stakes and snow pits. The δ¹⁸O and δD in rain samples range from -5.3% to -20.8% and -31.7% to -148.4% respectively. It is noteworthy to observe that the rain samples showed enriched values in the early season (July-August) and progressively get depleted at the end of the season (September). This could be due to the ‘amount effect’. Similarly, old snow samples have shown enriched isotopic values compared to fresh snow. This could because of the sublimation processes operating over the old surface snow. The δ¹⁸O and δD values in glacier ice samples range from -11.6% to -15.7% and -31.7% to -148.4%, whereas in a Sutri Dhaka meltwater stream, it ranges from -12.7% to -16.2% and -82.9% to -112.7% respectively. The mean deuterium excess (d-excess) value in all collected samples exceeds more than 16% which suggests the predominant moisture source of precipitation is from the Western Disturbances. Our detailed estimates of the hydrograph separation of Sutri Dhaka meltwater using isotope hydrograph separation and glaciological field methods agree within their uncertainty; stream meltwater budget is dominated by glaciers ice melt over snowmelt. The present study provides insights into the sources of moisture, controlling mechanism of the isotopic characteristics of Sutri Dhaka glacier water and helps in understanding the snow and ice melt components in Chandra basin, Western Himalaya.

Keywords: D-excess, hydrograph separation, Sutri Dhaka, stable water isotope, western Himalaya

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2873 Improving the Method for Characterizing Structural Fabrics for Shear Resistance and Formability

Authors: Dimitrios Karanatsis

Abstract:

Non-crimp fabrics (NCFs) allow for high mechanical performance of a manufacture composite component by maintaining the fibre reinforcements parallel to each other. The handling of NCFs is enabled by the stitching of the tows. Although the stitching material has negligible influence to the performance of the manufactured part, it can affect the ability of the structural fabric to shear and drape over the part’s geometry. High resistance to shearing is attributed to the high tensile strain of the stitching yarn and can cause defects in the fabric. In the current study, a correlation based on the stitch tension and shear behaviour is examined. The purpose of the research is to investigate the upper and lower limits of non-crimp fabrics manufacture and how these affect the shear behaviour of the fabrics. Experimental observations show that shear behaviour of the fabrics is significantly affected by the stitch tension, and there is a linear effect to the degree of shear they experience. It was found that the lowest possible stitch tension on the manufacturing line settings produces an NCF that exhibits very low tensile strain on it’s yarns and that has shear properties similar to a woven fabric. Moreover, the highest allowable stitch tension results in reduced formability of the fabric, as the stitch thread rearranges the fibre filaments where these become packed in a tight formation with constricted movement.

Keywords: carbon fibres, composite manufacture, shear testing, textiles

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2872 Homogeneous Anti-Corrosion Coating of Spontaneously Dissolved Defect-Free Graphene

Authors: M. K. Bin Subhan, P. Cullen, C. Howard

Abstract:

A recent study by the World Corrosion Organization estimated that corrosion related damage causes $2.5tr worth of damage every year. As such, a low cost easily scalable solution is required to the corrosion problem which is economically viable. Graphene is an ideal anti-corrosion barrier layer material due to its excellent barrier properties and chemical stability, which makes it impermeable to all molecules. However, attempts to employ graphene as a barrier layer has been hampered by the fact that defect sites in graphene accelerate corrosion due to the inert nature of graphene which promotes galvanic corrosion at the expense of the metal. The recent discovery of spontaneous dissolution of charged graphite intercalation compounds in aprotic solvents enables defect free graphene platelets to be employed for anti-corrosion applications. These ‘inks’ of defect-free charged graphene platelets in solution can be coated onto a metallic surfaces via electroplating to form a homogeneous barrier layer. In this paper, initial data showing homogeneous coatings of graphene barrier layers on steel coupons via electroplating will be presented. This easily scalable technique also provides a controllable method for applying different barrier thicknesses from ultra thin layers to thick opaque coatings making it useful for a wide range of applications.

Keywords: anti-corrosion, defect-free, electroplating, graphene

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2871 Effect of Pristine Graphene on Developmental Toxicity in Zebrafish (Danio rerio) Embryos: Cardiovascular Defects, Apoptosis, and Globin Expression Analysis

Authors: Manjunatha Bangeppagari, Lee Sang Joon

Abstract:

Recently, graphene-related nanomaterials are receiving fast-increasing attention with augmented applications in various fields. Especially, graphene-related materials have been widely applied to the biomedical field in the past years. In the present study, we evaluated the adverse effects of pristine graphene (pG) in zebrafish (Danio rerio) embryos in various aspects, such as mortality rate, heart rate, hatching rate, cardiotoxicity, cardiovascular defect, cardiac looping, apoptosis, and globin expression. For various trace concentrations of pG (1, 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 μg/L), early life-stage parameters were observed at 24, 48, 72, and 96 hpf. As a result, pG induces significant developmental defects including yolk sac edema, pericardial edema, embryonic mortality, delayed hatching, heartbeat, several morphological defects, pericardial toxicity, and bradycardia. Moreover, the exposure to pG was found to be a potential risk factor to the cardiovascular system of zebrafish embryos. However, further study on their properties which vary according to production methods and surface functionalization is essentially required. In addition, the possible risks of pG flakes to aquatic animals, and public health should be evaluated before releasing them to the surrounding environment.

Keywords: apoptosis, cardiovascular toxicity, globin expression, pristine graphene, zebrafish embryos

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2870 Preliminary Studies in the Determination of Deteriorations in Eflatunpınar Hitit Water Monument (Konya, Turkey) by Non-Destructive Tests

Authors: İsmail İnce, Ali Bozdag, Ayla Bozdag, M. Bahadır Tosunlar, M. Ergun Hatır, Mustafa Korkanc

Abstract:

The building stones used in the construction of historical structures are exposed to atmospheric effects directly or indirectly. As a result of this process, building stones are partially or completely degraded. Historical buildings are important symbols of cultural heritage, so it is very significant to transfer to the future generations by protecting and repairing of these historical buildings. The Eflatunpınar Hitit Monument located near the Eflatunpınar cold water spring was constructed by using natural rock blocks during the Hittites Empire period. The monument has been protected without losing its function until today. The purpose of this study is to evaluate the deteriorations in the Eflatunpınar Hitit Monument and to detect the water chemistry of the Eflatunpınar spring located around the Beysehir County in the west of Konya. For this purpose, the petrographic and mechanical properties of the rocks used in this monument were determined, and the deteriorations in the monument were determined with the aid of non-destructive test methods including Schmidt hardness value, relative humidity measurement, thermal imaging. Additionally, the physical (electrical conductivity (EC), pH and temperature) and chemical characteristics (major anions and cations) of the Eflatunpınar cold water spring have been detected.

Keywords: deteriorations, Eflatunpınar Hitit monument, Eflatunpınar spring, Konya, non-destructıve tests

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2869 Application of the Electrical Resistivity Tomography and Tunnel Seismic Prediction 303 Methods for Detection Fracture Zones Ahead of Tunnel: A Case Study

Authors: Nima Dastanboo, Xiao-Qing Li, Hamed Gharibdoost

Abstract:

The purpose of this study is to investigate about the geological properties ahead of a tunnel face with using Electrical Resistivity Tomography ERT and Tunnel Seismic Prediction TSP303 methods. In deep tunnels with hydro-geological conditions, it is important to study the geological structures of the region before excavating tunnels. Otherwise, it would lead to unexpected accidents that impose serious damage to the project. For constructing Nosoud tunnel in west of Iran, the ERT and TSP303 methods are employed to predict the geological conditions dynamically during the excavation. In this paper, based on the engineering background of Nosoud tunnel, the important results of applying these methods are discussed. This work demonstrates seismic method and electrical tomography as two geophysical techniques that are able to detect a tunnel. The results of these two methods were being in agreement with each other but the results of TSP303 are more accurate and quality. In this case, the TSP 303 method was a useful tool for predicting unstable geological structures ahead of the tunnel face during excavation. Thus, using another geophysical method together with TSP303 could be helpful as a decision support in excavating, especially in complicated geological conditions.

Keywords: tunnel seismic prediction (TSP303), electrical resistivity tomography (ERT), seismic wave, velocity analysis, low-velocity zones

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2868 Compression Index Estimation by Water Content and Liquid Limit and Void Ratio Using Statistics Method

Authors: Lizhou Chen, Abdelhamid Belgaid, Assem Elsayed, Xiaoming Yang

Abstract:

Compression index is essential in foundation settlement calculation. The traditional method for determining compression index is consolidation test which is expensive and time consuming. Many researchers have used regression methods to develop empirical equations for predicting compression index from soil properties. Based on a large number of compression index data collected from consolidation tests, the accuracy of some popularly empirical equations were assessed. It was found that primary compression index is significantly overestimated in some equations while it is underestimated in others. The sensitivity analyses of soil parameters including water content, liquid limit and void ratio were performed. The results indicate that the compression index obtained from void ratio is most accurate. The ANOVA (analysis of variance) demonstrates that the equations with multiple soil parameters cannot provide better predictions than the equations with single soil parameter. In other words, it is not necessary to develop the relationships between compression index and multiple soil parameters. Meanwhile, it was noted that secondary compression index is approximately 0.7-5.0% of primary compression index with an average of 2.0%. In the end, the proposed prediction equations using power regression technique were provided that can provide more accurate predictions than those from existing equations.

Keywords: compression index, clay, settlement, consolidation, secondary compression index, soil parameter

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2867 Developing Gifted Students’ STEM Career Interest

Authors: Wing Mui Winnie So, Tian Luo, Zeyu Han

Abstract:

To fully explore and develop the potentials of gifted students systematically and strategically by providing them with opportunities to receive education at appropriate levels, schools in Hong Kong are encouraged to adopt the "Three-Tier Implementation Model" to plan and implement the school-based gifted education, with Level Three refers to the provision of learning opportunities for the exceptionally gifted students in the form of specialist training outside the school setting by post-secondary institutions, non-government organisations, professional bodies and technology enterprises. Due to the growing concern worldwide about low interest among students in pursuing STEM (Science, Technology, Engineering, and Mathematics) careers, cultivating and boosting STEM career interest has been an emerging research focus worldwide. Although numerous studies have explored its critical contributors, little research has examined the effectiveness of comprehensive interventions such as “Studying with STEM professional”. This study aims to examine the effect on gifted students’ career interest during their participation in an off-school support programme designed and supervised by a team of STEM educators and STEM professionals from a university. Gifted students were provided opportunities and tasks to experience STEM career topics that are not included in the school syllabus, and to experience how to think and work like a STEM professional in their learning. Participants involved 40 primary school students joining the intervention programme outside the normal school setting. Research methods included adopting the STEM career interest survey and drawing tasks supplemented with writing before and after the programme, as well as interviews before the end of the programme. The semi-structured interviews focused on students’ views regarding STEM professionals; what’s it like to learn with a STEM professional; what’s it like to work and think like a STEM professional; and students’ STEM identity and career interest. The changes in gifted students’ STEM career interest and its well-recognised significant contributors, for example, STEM stereotypes, self-efficacy for STEM activities, and STEM outcome expectation, were collectively examined from the pre- and post-survey using T-test. Thematic analysis was conducted for the interview records to explore how studying with STEM professional intervention can help students understand STEM careers; build STEM identity; as well as how to think and work like a STEM professional. Results indicated a significant difference in STEM career interest before and after the intervention. The influencing mechanism was also identified from the measurement of the related contributors and the analysis of drawings and interviews. The potential of off-school support programme supervised by STEM educators and professionals to develop gifted students’ STEM career interest is argued to be further unleashed in future research and practice.

Keywords: gifted students, STEM career, STEM education, STEM professionals

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2866 Examining the Mediating and Moderating Role of Relationships in the Association between Poverty and Children’s Subjective Well-Being

Authors: Esther Yin-Nei Cho

Abstract:

There is inconsistency among studies about whether there is an association between poverty and the subjective wellbeing of children. Some have found a positive association, though its magnitude could be limited, others have shown no association. One possible explanation for this inconsistency is that household income, an often-adopted measure of child poverty, may not accurately and stably reflect the actual life experience of children. Some studies have suggested, however, that material deprivation covering various dimensions of children’s lives could be a better measure of child poverty. Another possible explanation for the inconsistency is that the link between poverty and subjective wellbeing of children may not be that straightforward, as there could be underlying mechanisms, such as mediation and moderation, influencing its direction or strength. While a mediator refers to the mechanism through which an independent variable affects a dependent variable, a moderator changes the direction or strength of the relationship between an independent variable and a dependent variable. As suggested by empirical evidence, family relationships and friendships could be potential mediators or moderators of the link between poverty and subjective well-being: poverty affects relationships; relationships are an important element in children’s subjective well-being; and economic status affects child outcomes, though not necessarily subjective wellbeing, through relationships. Since the potential links have not been adequately understood, this study fills this gap by examining the possible role of family relationships and friendships as mediators or moderators between poverty (using child-derived material deprivation as measure) and the subjective wellbeing of children. Improving subjective wellbeing is increasingly considered as a policy goal. The finding of no or a limited association between poverty and subjective wellbeing of children could be a justification for less effort to improve poverty in this regard. But if the observed magnitude of that association is due to some underlying mechanisms at work, the effect of poverty may be underestimated and the potentially useful strategies that take into account both poverty and other mediators or moderators for improving children’s subjective well-being may be overlooked. Multiple mediation, and multiple moderation models, based on regression analyses, are performed to a sample of approximately 1,600 children, who are aged 10 to 15, from the wellbeing survey conducted by The Children’s Society in England from 2010 to 2011. Results show that the effect of children’s material deprivation on their subjective well-being is mediated by their family relationships and friendships. Moreover, family relationships are a significant moderator. It is found that the negative impact of child deprivation on subjective wellbeing could be exacerbated if family relationships are not going well, while good family relationships may prevent the further decline in subjective well-being. Policy implications of the findings are discussed. In particular, policy measures that focus on strengthening the family relationships or nurturing home environment through supporting household’s economic security and parental time with children could promote the subjective wellbeing of children.

Keywords: child poverty, mediation, moderation, subjective well-being of children

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2865 Always Keep in Control: The Pattern of TV Policy Changes in China

Authors: Shan Jiang

Abstract:

China is a country with a distinct cultural system. The Chinese Communist Party (CCP) is the central factor for everything, which naturally includes culture. There are quite a lot of cultural policies in China. The same goes for TV dramas. This paper traces the evolution of Chinese TV drama policy since 1986, examines the realistic situation behind the changes, and explores the structure and role of the government in shaping the process. Using historical documents and media reports, it first analyzes four key time nodes: 1986, 2003, 2012, and 2022. It shows how the policy shifts from restricting private production to opening up to public participation, from imposing one censorship to another, and from promoting some content to restricting some other area. It finds that the policy process is not simply rectilinear but rather wandering between deregulation and strengthening control. Secondly, it divides the policies into "basic" policies that establish the overall layout and more refined "strategic" policies that respond to more refined needs. It argues that the "basic" policy process is caused by China's political, economic, and cultural system reform, and then the "strategic" policy process is affected by more environmental factors, such as the government's follow-up development strategy, industrial development, technological innovation, and specific situations. Thirdly, it analysis the main body of the 104 policies from 2000 to 2021 and puts these subjects into China's power structure and cultural system, revealing that the policy issuers are all under the highest leadership of the Chinese Central Committee. Further, the paper challenges the typical description of Chinese cultural policy, which focuses on state control exclusively, identifies the forces within and outside the system that participate in or affect the policy-making process, and reveals the inter-subjective mechanism of policy change. In conclusion, the paper reveals that China's TV drama policy is under the unified leadership of the Party and the government, which greatly guarantees the consistency of the overall direction of cultural policy, that is, the right to speak firmly in the hands. The forces within the system can sometimes promote policy changes due to common development needs. However, folk discourse is only the object of control: when it breeds a certain amount of industrial space, the government will strengthen control over this space, suppress its potential "adverse effects", and instead provide protection and create conditions for the cultivation and growth of its mainstream discourse. However, the policy combination of basic policy and strategic policy, while having a strong effect and emergency capacity, also inhibits the innovation and diversification of the TV drama market. However, the state's substantial regulation will continue to exist in the future.

Keywords: TV Policy, China, policy process, cultural policy, culture management

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2864 Sukh Initiative: A Family Planning Reproductive Health Project for Squatter Settlement of Karachi, Pakistan

Authors: Arshad Hussain

Abstract:

Background: Sukh Initiative is a multi-donor funded, family planning and reproductive health project, primed by Aman Healthcare Services; implemented through a consortium of local and international organizations, in a selected one million underserved peri-urban population of Karachi, Sindh; which aims at increasing modern contraceptive prevalence rate by 15 percentage point. Objective: To empower women to access contraception by increasing knowledge, improving quality of services and expanding the basket of choices; contributing to the goals of FP2020. Methods: A five years project has a multi-pronged approach with door to door services by LHWs and CHWs in an LHWs covered population and provision of quality FP/RH services both at public and private health care facilities. The project engages youth (12-16 years) both with community and at secondary schools to mentor them for responsible adulthood with life skilled base initiative. A 24/7 availability of youth and FP helpline service provides counselling, referrals in addition with a follow-up mechanism. Results: 131,810 MWRAs were reached by 191 community health workers through 29,693 of community support group meetings and 166,775 house hold visits. These MWRAs were counselled on FP related myths and misconception and referred to 216 providers trained for quality family planning services and maintaining average 64% quality scores in 43 public health and 35 private facilities in the project area. Of those referred 26% MWRAs opted modern contraception with 17.56% in LARCs and 41% PPFP as compared to baseline. Aman TeleHealth is linked with 24/7 counselling, referrals and post services follow-ups to clients, showing 14% proportion of FP call volume. Sukh has a unique role in engaging all partners on youth SRHR issues through family life education sessions, 30 higher sec. schools in Sukh area have been provided LSBE to 16,000 students (aged 15-17), and in community approximately 10, 496 girls and boys have received SRHR information. Conclusion: Through individual counselling, access to quality family planning services and involvement of stakeholders, Suk created an enabling environment to rapid increase in family planning in the project intervention area.

Keywords: family planning and reproductive health, married women with reproductive age, urban squatter, Pakistan

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2863 A Stochastic Analytic Hierarchy Process Based Weighting Model for Sustainability Measurement in an Organization

Authors: Faramarz Khosravi, Gokhan Izbirak

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A weighted statistical stochastic based Analytical Hierarchy Process (AHP) model for modeling the potential barriers and enablers of sustainability for measuring and assessing the sustainability level is proposed. For context-dependent potential barriers and enablers, the proposed model takes the basis of the properties of the variables describing the sustainability functions and was developed into a realistic analytical model for the sustainable behavior of an organization. This thus serves as a means for measuring the sustainability of the organization. The main focus of this paper was the application of the AHP tool in a statistically-based model for measuring sustainability. Hence a strong weighted stochastic AHP based procedure was achieved. A case study scenario of a widely reported major Canadian electric utility was adopted to demonstrate the applicability of the developed model and comparatively examined its results with those of an equal-weighted model method. Variations in the sustainability of a company, as fluctuations, were figured out during the time. In the results obtained, sustainability index for successive years changed form 73.12%, 79.02%, 74.31%, 76.65%, 80.49%, 79.81%, 79.83% to more exact values 73.32%, 77.72%, 76.76%, 79.41%, 81.93%, 79.72%, and 80,45% according to priorities of factors that have found by expert views, respectively. By obtaining relatively necessary informative measurement indicators, the model can practically and effectively evaluate the sustainability extent of any organization and also to determine fluctuations in the organization over time.

Keywords: AHP, sustainability fluctuation, environmental indicators, performance measurement

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2862 A Perspective of Digital Formation in the Solar Community as a Prototype for Finding Sustainable Algorithmic Conditions on Earth

Authors: Kunihisa Kakumoto

Abstract:

“Purpose”: Global environmental issues are now being raised in a global dimension. By predicting sprawl phenomena beyond the limits of nature with algorithms, we can expect to protect our social life within the limits of nature. It turns out that the sustainable state of the planet now consists in maintaining a balance between the capabilities of nature and the possibilities of our social life. The amount of water on earth is finite. Sustainability is therefore highly dependent on water capacity. A certain amount of water is stored in the forest by planting and green space, and the amount of water can be considered in relation to the green space. CO2 is also absorbed by green plants. "Possible measurements and methods": The concept of the solar community has been introduced in technical papers on the occasion of many international conferences. The solar community concept is based on data collected from one solar model house. This algorithmic study simulates the amount of water stored by lush green vegetation. In addition, we calculated and compared the amount of CO2 emissions from the Taiyo Community and the amount of CO2 reduction from greening. Based on the trial calculation results of these solar communities, we are simulating the sustainable state of the earth as an algorithm trial calculation result. We believe that we should also consider the composition of this solar community group using digital technology as control technology. "Conclusion": We consider the solar community as a prototype for finding sustainable conditions for the planet. The role of water is very important as the supply capacity of water is limited. However, the circulation of social life is not constructed according to the mechanism of nature. This simulation trial calculation is explained using the total water supply volume as an example. According to this process, algorithmic calculations consider the total capacity of the water supply and the population and habitable numbers of the area. Green vegetated land is very important to keep enough water. Green vegetation is also very important to maintain CO2 balance. A simulation trial calculation is possible from the relationship between the CO2 emissions of the solar community and the amount of CO2 reduction due to greening. In order to find this total balance and sustainable conditions, the algorithmic simulation calculation takes into account lush vegetation and total water supply. Research to find sustainable conditions is done by simulating an algorithmic model of the solar community as a prototype. In this one prototype example, it's balanced. The activities of our social life must take place within the permissive limits of natural mechanisms. Of course, we aim for a more ideal balance by utilizing auxiliary digital control technology such as AI.

Keywords: solar community, sustainability, prototype, algorithmic simulation

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2861 Psychotherapeutic Narratives and the Importance of Truth

Authors: Spencer Jay Knafelc

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Some mental health practitioners and theorists have suggested that we approach remedying psychological problems by centering and intervening upon patients’ narrations. Such theorists and their corresponding therapeutic approaches see persons as narrators of their lives, where the stories they tell constitute and reflect their sense-making of the world. Psychological problems, according to these approaches to therapy, are often the result of problematic narratives. The solution is the construction of more salubrious narratives through therapy. There is trouble lurking within the history of these narrative approaches. These thinkers tend to denigrate the importance of truth, insisting that narratives are not to be thought of as aiming at truth, and thus the truth of our self-narratives is not important. There are multiple motivations for the tendency to eschew truth’s importance within the tradition of narrative approaches to therapy. The most plausible and interesting motivation comes from the observation that, in general, all dominant approaches to therapy are equally effective. The theoretical commitments of each approach are quite different and are often ostensibly incompatible (psychodynamic therapists see psychological problems as resulting from unconscious conflict and repressed desires, Cognitive-Behavioral approaches see them as resulting from distorted cognitions). This strongly suggests that there must be some cases in which therapeutic efficacy does not depend on truth and that insisting that patient’s therapeutic narratives be true in all instances is a mistake. Lewis’ solution is to suggest that narratives are metaphors. Lewis’ account appreciates that there are many ways to tell a story and that many different approaches to mental health treatment can be appropriate without committing us to any contradictions, providing us with an ostensibly coherent way to treat narratives as non-literal, instead of seeing them as tools that can be more or less apt. Here, it is argued that Lewis’ metaphor approach fails. Narratives do not have the right kind of structure to be metaphors. Still, another way to understand Lewis’ view might be that self-narratives, especially when articulated in the language of any specific approach, should not be taken literally. This is an idea at the core of the narrative theorists’ tendency to eschew the importance of the ordinary understanding of truth. This very tendency will be critiqued. The view defended in this paper more accurately captures the nature of self-narratives. The truth of one’s self-narrative is important. Not only do people care about having the right conception of their abilities, who they are, and the way the world is, but self-narratives are composed of beliefs, and the nature of belief is to aim at truth. This view also allows the recognition of the importance of developing accurate representations of oneself and reality for one’s psychological well-being. It is also argued that in many cases, truth factors in as a mechanism of change over the course of therapy. Therapeutic benefit can be achieved by coming to have a better understanding of the nature of oneself and the world. Finally, the view defended here allows for the recognition of the nature of the tension between values: truth and efficacy. It is better to recognize this tension and develop strategies to navigate it as opposed to insisting that it doesn’t exist.

Keywords: philosophy, narrative, psychotherapy, truth

Procedia PDF Downloads 102
2860 Disaster Mitigation from an Analysis of a Condemned Building Erected over Collapsible Clay Soil in Brazil

Authors: Marcelo Jesus Kato Avila, Joao Da Costa Pantoja

Abstract:

Differential settlement of foundations is a serious pathology in buildings that put at risk lives and property. A common reason for the occurrence of this specific pathology in central Brazil is the presence of collapsible clay, a typical soil in the region. In this study, the foundation of a condemned building erected above this soil is analyzed. The aim is to prevent problems in new constructions, to predict which buildings may be subjected to damages, and to make possible a more precise treatment in less advanced differential settlements observed in the buildings of the vicinity, which includes a hospital, a Military School, an indoor sporting arena, the Police Academy, and the Military Police Headquarters. The methodology consists of visual inspection, photographic report of the main pathologies, analysis of the existing foundations, determination of the soil properties, the study of the cracking level and assessment of structural failure risk of the building. The findings show that the presence of water weaken the soil structure on which the foundation rest, being the main cause of the pathologic settlement, indicating that even in a one store building it was necessary to consider deeper digging, other categories of foundations, and more elaborated and detailed foundation plans when the soil presents this behavior.

Keywords: building cracks, collapsible clay, differential settlement, structural failure risk

Procedia PDF Downloads 251
2859 Creep Compliance Characteristics of Cement Dust Asphalt Concrete Mixtures

Authors: Ayman Othman, Tallat Abd el Wahed

Abstract:

The current research is directed towards studying the creep compliance characteristics of asphalt concrete mixtures modified with cement dust. This study can aid in assessing the permanent deformation potential of asphalt concrete mixtures. Cement dust was added to the mixture as mineral filler and compared with regular lime stone filler. A power law model was used to characterize the creep compliance behavior of the studied mixtures. Creep testing results have revealed that the creep compliance power law parameters have a strong relationship with mixture type. Testing results of the studied mixtures, as indicated by the creep compliance parameters revealed an enhancement in the creep resistance, Marshall stability, indirect tensile strength and compressive strength for cement dust mixtures as compared to mixtures with traditional lime stone filler. It is concluded that cement dust can be successfully used to decrease the potential of asphalt concrete mixture to permanent deformation and improve its mechanical properties. This is in addition to the environmental benefits that can be gained when using cement dust in asphalt paving technology.

Keywords: cement dust, asphalt concrete mixtures, creep compliance, Marshall stability, indirect tensile strength, compressive strength

Procedia PDF Downloads 421
2858 Litigating Innocence in the Era of Forensic Law: The Problem of Wrongful Convictions in the Absence of Effective Post-Conviction Remedies in South Africa

Authors: Tapiwa Shumba

Abstract:

The right to fairness and access to appeals and reviews enshrined under the South African Constitution seeks to ensure that justice is served. In essence, the constitution and the law have put in place mechanisms to ensure that a miscarriage of justice through wrongful convictions does not occur. However, once convicted and sentenced on appeal the procedural safeguards seem to resign as if to say, the accused has met his fate. The challenge with this construction is that even within an ideally perfect legal system wrongful convictions would still occur. Therefore, it is not so much of the failings of a legal system that demand attention but mechanisms to redress the results of such failings where evidence becomes available that a wrongful conviction occurred. In this context, this paper looks at the South African criminal procedural mechanisms for litigating innocence post-conviction. The discussion focuses on the role of section 327 of the South African Criminal Procedure Act and its apparent shortcomings in providing an avenue for victims of miscarriages to litigate their innocence by adducing new evidence at any stage during their wrongful incarceration. By looking at developments in other jurisdiction such as the United Kingdom, where South African criminal procedure draws much of its history, and the North Carolina example which in itself was inspired by the UK Criminal Cases Review Commission, this paper is able to make comparisons and draw invaluable lessons for the South African criminal justice system. Lessons from these foreign jurisdictions show that South African post-conviction criminal procedures need reform in line with constitutional values of human dignity, equality before the law, openness and transparency. The paper proposes an independent review of the current processes to assess the current post-conviction procedures under section 327. The review must look into the effectiveness of the current system and how it can be improved in line with new substantive legal provisions creating access to DNA evidence for post-conviction exonerations. Although the UK CCRC body should not be slavishly followed, its operations and the process leading to its establishment certainly provide a good point of reference and invaluable lessons for the South African criminal justice system seeing that South African law on this aspect has generally followed the English approach except that current provisions under section 327 are a mirror of the discredited system of the UK’s previous dispensation. A new independent mechanism that treats innocent victims of the criminal justice system with dignity away from the current political process is proposed to enable the South African criminal justice to benefit fully from recent and upcoming advances in science and technology.

Keywords: innocence, forensic law, post-conviction remedies, South African criminal justice system, wrongful conviction

Procedia PDF Downloads 235
2857 Fatigue Life Estimation of Tubular Joints - A Comparative Study

Authors: Jeron Maheswaran, Sudath C. Siriwardane

Abstract:

In fatigue analysis, the structural detail of tubular joint has taken great attention among engineers. The DNV-RP-C203 is covering this topic quite well for simple and clear joint cases. For complex joint and geometry, where joint classification isn’t available and limitation on validity range of non-dimensional geometric parameters, the challenges become a fact among engineers. The classification of joint is important to carry out through the fatigue analysis. These joint configurations are identified by the connectivity and the load distribution of tubular joints. To overcome these problems to some extent, this paper compare the fatigue life of tubular joints in offshore jacket according to the stress concentration factors (SCF) in DNV-RP-C203 and finite element method employed Abaqus/CAE. The paper presents the geometric details, material properties and considered load history of the jacket structure. Describe the global structural analysis and identification of critical tubular joints for fatigue life estimation. Hence fatigue life is determined based on the guidelines provided by design codes. Fatigue analysis of tubular joints is conducted using finite element employed Abaqus/CAE [4] as next major step. Finally, obtained SCFs and fatigue lives are compared and their significances are discussed.

Keywords: fatigue life, stress-concentration factor, finite element analysis, offshore jacket structure

Procedia PDF Downloads 448
2856 Understanding the Reasons for Flooding in Chennai and Strategies for Making It Flood Resilient

Authors: Nivedhitha Venkatakrishnan

Abstract:

Flooding in urban areas in India has become a usual ritual phenomenon and a nightmare to most cities, which is a consequence of man-made disruption resulting in disaster. The City planning in India falls short of withstanding hydro generated disasters. This has become a barrier and challenge in the process of development put forth by urbanization, high population density, expanding informal settlements, environment degradation from uncollected and untreated waste that flows into natural drains and water bodies, this has disrupted the natural mechanism of hazard protection such as drainage channels, wetlands and floodplains. The magnitude and the impact of the mishap was high because of the failure of development policies, strategies, plans that the city had adopted. In the current scenario, cities are becoming the home for future, with economic diversification bringing in more investment into cities especially in domains of Urban infrastructure, planning and design. The uncertainty of the Urban futures in these low elevated coastal zones faces an unprecedented risk and threat. The study on focuses on three major pillars of resilience such as Recover, Resist and Restore. This process of getting ready to handle the situation bridges the gap between disaster response management and risk reduction requires a shift in paradigm. The study involved a qualitative research and a system design approach (framework). The initial stages involved mapping out of the urban water morphology with respect to the spatial growth gave an insight of the water bodies that have gone missing over the years during the process of urbanization. The major finding of the study was missing links between traditional water harvesting network was a major reason resulting in a manmade disaster. The research conceptualized the ideology of a sponge city framework which would guide the growth through institutional frameworks at different levels. The next stage was on understanding the implementation process at various stage to ensure the shift in paradigm. Demonstration of the concepts at a neighborhood level where, how, what are the functions and benefits of each component. Quantifying the design decision with rainwater harvest, surface runoff and how much water is collected and how it could be collected, stored and reused. The study came with further recommendation for Water Mitigation Spaces that will revive the traditional harvesting network.

Keywords: flooding, man made disaster, resilient city, traditional harvesting network, waterbodies

Procedia PDF Downloads 138
2855 Evaluation of the UV Stability of Unidirectional Crossply Ultrahigh-Molecular-Weight-Polyethylene Composite

Authors: Jonmichael Weaver, David Miller

Abstract:

Dyneema is an ultra-high molecular weight polyethylene (UHMWPE) fiber created by DSM. This fiber has many applications due to the high tensile strength, low weight, and inability to absorb water. DSM manufactures a non-woven unidirectional cross-ply [0,90]2 lamina, using the Dyneema fiber. Using this lamina system, various thickness panels are created for a 40% lighter weight alternative to Kevlar for the same ballistics protection. Environmental effects on the ply/laminate system alter the material properties, resulting in diminished ultimate performance. Understanding the specific environmental parameters and characterizing the resulting material property degradation is essential for determining the safety and reliability of Dyneema in service. Two laminas were contrasted for their response to accelerated aging by UV, humidity, and temperature cycling. Both lamina contain the same fiber, SK-99, but differ in matrix composition, Dyneema HB-210 employs a polyurethane (PUR) based matrix, and HB-212 contains a rubber-based matrix. Each system was inspected using a scanning electron microscope (SEM) and evaluated by dynamic mechanical analysis (DMA) to characterize the material property changes alongside the corresponding composite damage and matrix failure mode over the aging parameters. Overall, resulting in the HB-212 degrading faster compared with the HB-210.

Keywords: dyneema, accelerated aging, polymers, ballistics protection, armor, DSM, kevlar, composites

Procedia PDF Downloads 147
2854 Bridging Stress Modeling of Composite Materials Reinforced by Fiber Using Discrete Element Method

Authors: Chong Wang, Kellem M. Soares, Luis E. Kosteski

Abstract:

The problem of toughening in brittle materials reinforced by fibers is complex, involving all the mechanical properties of fibers, matrix, the fiber/matrix interface, as well as the geometry of the fiber. An appropriate method applicable to the simulation and analysis of toughening is essential. In this work, we performed simulations and analysis of toughening in brittle matrix reinforced by randomly distributed fibers by means of the discrete elements method. At first, we put forward a mechanical model of the contribution of random fibers to the toughening of composite. Then with numerical programming, we investigated the stress, damage and bridging force in the composite material when a crack appeared in the brittle matrix. From the results obtained, we conclude that: (i) fibers with high strength and low elasticity modulus benefit toughening; (ii) fibers with relatively high elastic modulus compared to the matrix may result in considerable matrix damage (spalling effect); (iii) employment of high-strength synthetic fiber is a good option. The present work makes it possible to optimize the parameters in order to produce advanced ceramic with desired performance. We believe combination of the discrete element method (DEM) with the finite element method (FEM) can increase the versatility and efficiency of the software developed.

Keywords: bridging stress, discrete element method, fiber reinforced composites, toughening

Procedia PDF Downloads 441
2853 Incidence of Breast Cancer and Enterococcus Infection: A Retrospective Analysis

Authors: Matthew Cardeiro, Amalia D. Ardeljan, Lexi Frankel, Dianela Prado Escobar, Catalina Molnar, Omar M. Rashid

Abstract:

Introduction: Enterococci comprise the natural flora of nearly all animals and are ubiquitous in food manufacturing and probiotics. However, its role in the microbiome remains controversial. The gut microbiome has shown to play an important role in immunology and cancer. Further, recent data has suggested a relationship between gut microbiota and breast cancer. These studies have shown that the gut microbiome of patients with breast cancer differs from that of healthy patients. Research regarding enterococcus infection and its sequala is limited, and further research is needed in order to understand the relationship between infection and cancer. Enterococcus may prevent the development of breast cancer (BC) through complex immunologic and microbiotic adaptations following an enterococcus infection. This study investigated the effect of enterococcus infection and the incidence of BC. Methods: A retrospective study (January 2010- December 2019) was provided by a Health Insurance Portability and Accountability Act (HIPAA) compliant national database and conducted using a Humans Health Insurance Database. International Classification of Disease (ICD) 9th and 10th codes, Current Procedural Terminology (CPT), and National Drug Codes were used to identify BC diagnosis and enterococcus infection. Patients were matched for age, sex, Charlson Comorbidity Index (CCI), antibiotic treatment, and region of residence. Chi-squared, logistic regression, and odds ratio were implemented to assess the significance and estimate relative risk. Results: 671 out of 28,518 (2.35%) patients with a prior enterococcus infection and 1,459 out of 28,518 (5.12%) patients without enterococcus infection subsequently developed BC, and the difference was statistically significant (p<2.2x10⁻¹⁶). Logistic regression also indicated enterococcus infection was associated with a decreased incidence of BC (RR=0.60, 95% CI [0.57, 0.63]). Treatment for enterococcus infection was analyzed and controlled for in both enterococcus infected and noninfected populations. 398 out of 11,523 (3.34%) patients with a prior enterococcus infection and treated with antibiotics were compared to 624 out of 11,523 (5.41%) patients with no history of enterococcus infection (control) and received antibiotic treatment. Both populations subsequently developed BC. Results remained statistically significant (p<2.2x10-16) with a relative risk of 0.57 (95% CI [0.54, 0.60]). Conclusion & Discussion: This study shows a statistically significant correlation between enterococcus infection and a decrease incidence of breast cancer. Further exploration is needed to identify and understand not only the role of enterococcus in the microbiome but also the protective mechanism(s) and impact enterococcus infection may have on breast cancer development. Ultimately, further research is needed in order to understand the complex and intricate relationship between the microbiome, immunology, bacterial infections, and carcinogenesis.

Keywords: breast cancer, enterococcus, immunology, infection, microbiome

Procedia PDF Downloads 168
2852 A Low Cost Non-Destructive Grain Moisture Embedded System for Food Safety and Quality

Authors: Ritula Thakur, Babankumar S. Bansod, Puneet Mehta, S. Chatterji

Abstract:

Moisture plays an important role in storage, harvesting and processing of food grains and related agricultural products. It is an important characteristic of most agricultural products for maintenance of quality. Accurate knowledge of the moisture content can be of significant value in maintaining quality and preventing contamination of cereal grains. The present work reports the design and development of microcontroller based low cost non-destructive moisture meter, which uses complex impedance measurement method for moisture measurement of wheat using parallel plate capacitor arrangement. Moisture can conveniently be sensed by measuring the complex impedance using a small parallel-plate capacitor sensor filled with the kernels in-between the two plates of sensor, exciting the sensor at 30 KHz and 100 KHz frequencies. The effects of density and temperature variations were compensated by providing suitable compensations in the developed algorithm. The results were compared with standard dry oven technique and the developed method was found to be highly accurate with less than 1% error. The developed moisture meter is low cost, highly accurate, non-destructible method for determining the moisture of grains utilizing the fast computing capabilities of microcontroller.

Keywords: complex impedance, moisture content, electrical properties, safety of food

Procedia PDF Downloads 460
2851 Applicability of Soybean as Bio-Catalyst in Calcite Precipitated Method for Soil Improvement

Authors: Heriansyah Putra, Erizal Erizal, Sutoyo Sutoyo, Hideaki Yasuhara

Abstract:

This paper discusses the possibility of organic waste material, i.e., soybean, as the bio-catalyst agent on the calcite precipitation method. Several combinations of soybean powder and jack bean extract are used as the bio-catalyst and mixed with the reagent composed of calcium chloride and urea. Its productivity in promoting calcite crystal is evaluated through a transparent test-tube experiment. The morphological and mineralogical aspects of precipitated calcite are also investigated using scanning electromagnetic (SEM) and X-ray diffraction (XRD), respectively. The applicability of this material to improve the engineering properties of soil are examined using the direct shear and unconfined compressive test. The result of this study shows that the utilization of soybean powder brings about a significant effect on soil strength. In addition, the use of soybean powder as a substitution material of urease enzyme also increases the efficacy of calcite crystal as the binder materials. The low calcite content promotes the high strength of the soil. The strength of 300 kPa is obtained in the presence of 2% of calcite content within the soil. The result of this study elucidated that substitution of soybean to jack bean extract is the potential and valuable alternative to improve the applicability of calcite precipitation method as soil improvement technique.

Keywords: calcite precipitation, jack bean, soil improvement, soybean

Procedia PDF Downloads 122
2850 Mechanical Properties of Graphene Nano-Platelets Coated Carbon-Fiber Composites

Authors: Alok Srivastava, Vidit Gupta, Aparna Singh, Chandra Sekher Yerramalli

Abstract:

Carbon-fiber epoxy composites show extremely high modulus and strength in the uniaxial direction. However, they are prone to fail under low load in transverse direction due to the weak nature of the interface between the carbon-fiber and epoxy. In the current study, we have coated graphene nano-platelets (GNPs) on the carbon-fibers in an attempt to strengthen the interface/interphase between the fiber and the matrix. Vacuum Assisted Resin Transfer Moulding (VARTM) has been used to make the laminates of eight cross-woven fabrics. Tensile, flexural and fracture toughness tests have been performed on pristine carbon-fiber composite (P-CF), GNP coated carbon-fiber composite (GNP-CF) and functionalized-GNP coated carbon-fiber composite (F-GNP-CF). The tensile strength and flexural strength values are pretty similar for P-CF and GNP-CF. The micro-structural examination of the GNP coated carbon-fibers, as well as the fracture surfaces, have been carried out using scanning electron microscopy (SEM). The micrographs reveal the deposition of GNPs onto the carbon fibers in transverse and longitudinal direction. Fracture surfaces show the debonding and pull outs of the carbon fibers in P-CF and GNP-CF samples.

Keywords: carbon fiber, graphene nanoplatelets, strength, VARTM, Vacuum Assisted Resin Transfer Moulding

Procedia PDF Downloads 144
2849 Preparation of Biomedical Hydrogels Using Phenolic Compounds and Electron Beam Irradiation

Authors: Farnaz Sadeghi, Moslem Tavakol

Abstract:

In this study, an attempt has been made to prepare a physically cross-linked gel by cooling of tannic acid (TA)-polyvinyl alcohol (PVA) solution that subsequently convert to antibacterial chemically cross-linked hydrogel by using electron beam irradiation. PVA is known for its biocompatibility and hydrophilicity, and TA is known for being a natural compound which can serve as a cross-linking agent and a therapeutic agent. Swelling behavior, gel content, pore size, and mechanical properties of hydrogels which prepared at 14, 28, and 56 (kGy) with different ratios of polymers were investigated. PVA-TA hydrogel showed sustained release of tannic acid as approximately 20% and 50% of loaded TA released from the hydrogel after 4 and 72 h release time. We found that gel content decreased and the moisture retention capability increased by an increase in TA composition. In addition, PVA-TA hydrogels showed a good antibacterial activity against S.aureus. MTT analysis indicated that close to 83% of fibroblast cells remained viable after 48 h exposure to hydrogel extract. Moreover, the cooling of 10% PVA solution containing 0.5 and 0.75% w/v tannic acid to room and refrigerator, respectively, led to formation of physical gel that did not present any flow index after inversion of hydrogel cast. According to the results, the hydrogel prepared by electron beam irradiation of blended PVA-TA solution could be further investigated as a promising candidate for wound healing.

Keywords: poly vinyl alcohol, tannic acid, electron beam irradiation, hydrogel wound dressing

Procedia PDF Downloads 151