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Authors: Hamed Yaghoubi, Esmaeil Salahi, Fateme Taati

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The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermomechanical characteristics of the material such as relative density, temperature, grain size, and diffusion coefficient and activation energy. The main goal of this research is to acquire a comprehensive understanding of the response of an incompressible viscose ceramic material during liquid phase sintering process such as stress-strain relations, sintering and hydrostatic stress, the prediction of anisotropic shrinkage and heterogeneous densification as a function of sintering time by including the simultaneous influence of gravity field, and frictional force. After raw materials analysis, the standard hard porcelain mixture as a ceramic body was designed and prepared. Three different experimental configurations were designed including midpoint deflection, sinter bending, and free sintering samples. The numerical method for the ceramic specimens during the liquid phase sintering process are implemented in the CREEP user subroutine code in ABAQUS. The numerical-experimental procedure shows the anisotropic behavior, the complete difference in spatial displacement through three directions, the incompressibility for ceramic samples during the sintering process. The anisotropic shrinkage factor has been proposed to investigate the shrinkage anisotropy. It has been shown that the shrinkage along the normal axis of casting sample is about 1.5 times larger than that of casting direction, the gravitational force in pyroplastic deformation intensifies the shrinkage anisotropy more than the free sintering sample. The lowest and greatest equivalent creep strain occurs at the intermediate zone and around the central line of the midpoint distorted sample, respectively. In the sinter bending test sample, the equivalent creep strain approaches to the maximum near the contact area with refractory support. The inhomogeneity in Von-Misses, pressure, and principal stress intensifies the relative density non-uniformity in all samples, except in free sintering one. The symmetrical distribution of stress around the center of free sintering sample, cause to hinder the pyroplastic deformations. Densification results confirmed that the effective bulk viscosity was well-defined with relative density values. The stress analysis confirmed that the sintering stress is more than the hydrostatic stress from start to end of sintering time so, from both theoretically and experimentally point of view, the sintering process occurs completely.

Keywords: anisotropic shrinkage, ceramic material, liquid phase sintering process, rheological properties, numerical-experimental procedure

Procedia PDF Downloads 335

Authors: Fei Chen, Wei Lu, Jun Cai

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During the Twelve Five period, China promulgated industrial policies promoting the relocation of energy-intensive industries to coastal areas in order to utilize marine shipping resources. Consequently, some major state-owned steel and gas enterprises have relocated and resulted in a large-scale coastal area development. However, some land may have been over-exploited with seamless coastline projects. To balance between employment and housing, new industrial coastal towns were constructed to support the industrial-led development. In this paper, we adopt a case-study approach to closely examine the development of several new industrial coastal towns of Liaoning Province situated in the Bohai Bay area, which is currently under rapid economic growth. Our investigations reflect the common phenomenon of long distance commuting and a massive amount of vacant residences. More specifically, large plant relocation caused hundreds of kilometers of daily commute and enterprises had to provide housing subsidies and education incentives to motivate employees to relocate to coastal areas. Nonetheless, many employees still refuse to relocate due to job stability, diverse needs of family members and access to convenient services. These employees averaged 4 hours of commute daily and some who lived further had to reside in temporary industrial housing units and subject to long-term family separation. As a result, only a small portion of employees purchase new coastal residences but mostly for investment and retirement purposes, leading to massive vacancy and ghost-town phenomenon. In contrast to the low demand, coastal areas tend to develop large amount of residences prior to industrial relocation, which may be directly related to local government finances. Some local governments have sold residential land to developers to general revenue to support the subsequent industrial development. Subject to the strong preference of ocean-view, residential housing developers tend to select coast-line land to construct new residential towns, which further reduces the access of marine resources for major industrial enterprises. This violates the original intent of developing industrial coastal towns and drastically limits the availability of marine resources. Lastly, we analyze the co-existence of over-exploiting residential areas and massive vacancies in reference to the demand and supply of land, as well as the demand of residential housing units with the choice criteria of enterprise employees.

Keywords: coastal industry town, commuter traffic, employment-housing space, outer suburb industrial area

Procedia PDF Downloads 215

Authors: Owonikoko Abayomi Dele

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Epilepsy is an unresolved disease that needs urgent attention. It is a brain disorder that affects over sixty-five (65) million people around the globe. Despite the availability of commercial anti-epileptic drugs, the war against this unmet condition is yet to be resolved. Most epilepsy patients are resistant to available anti-epileptic medications thus the need for affordable novel therapy against epilepsy is a necessity. Numerous phytochemicals have been reported for their potency, efficacy and safety as therapeutic agents against many diseases. This study investigated 99 isolated phytochemicals from Chasmanthera dependens and Carissa edulis against carbonic anhydrase (ii) drug target. The absorption, distribution, metabolism, excretion and toxicity (ADMET) of the isolated compounds were examined using admet SAR-2 web server while Swiss ADME was used to analyze the oral bioavailability, drug-likeness and lead-likeness properties of the selected leads. PASS web server was used to predict the biological activities of selected leads while other important physicochemical properties and interactions of the selected leads with the active site of the target after successful molecular docking simulation with the pyrx virtual screening tool were also examined. The results of these study identified seven lead compounds; C49- alpha-carissanol (-7.6 kcal/mol), C13- Catechin (-7.4 kcal/mol), C45- Salicin (-7.4 kcal/mol), C6- Bisnorargemonine (-7.3 kcal/mol), C36- Pallidine (-7.1 kcal/mol), S4- Lacosamide (-7.1 kcal/mol), and S7- Acetazolamide (-6.4 kcal/mol) for CA II (3HS4 receptor). These leads compounds are probable inhibitors of this drug target due to the observed good binding affinities and favourable interactions with the active site of the drug target, excellent ADMET profiles, PASS Properties, drug-likeness, lead-likeness and oral bioavailability properties. The identified leads have better binding energies as compared to the binding energies of the two standards. Thus, seven identified lead compounds can be developed further towards the development of new anti-epileptic medications.

Keywords: drug-likeness, phytochemicals, carbonic anhydrases, metalloeazymes, active site, ADMET

Procedia PDF Downloads 39

Authors: Onesimus Bulus Shiaki

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The study investigated the effect of cooperative learning strategy on mathematics achievement and retention among senior secondary school students of different abilities in Taraba State Nigeria. Cooperative learning strategy could hopefully contribute to students’ achievement which will spur the teachers to develop strategies for better learning. The quasi-experimental of pretest, posttest and control group design was adopted in this study. A sample of one hundred and sixty-four (164) Senior Secondary Two (SS2) students were selected from a population of twelve thousand, eight hundred and seventy-three (12,873) SS2 Students in Taraba State. Two schools with equivalent mean scores in the pre-test were randomly assigned to experimental and control groups. The experimental group students were stratified according to ability levels of low, medium and high. The experimental group was guided by the research assistants using the cooperative learning instructional package. After six weeks post-test was administered to the two groups while the retention test was administered two weeks after the post-test. The researcher developed a 50-item Mathematics Achievement Test (MAT) which was validated by experts obtaining the reliability coefficient of 0.87. Mean scores and standard deviations were used to answer the research questions while the Analysis of Co-variance (ANCOVA) was used to test the hypotheses. Major findings from the statistical analysis showed that cooperative learning strategy has a significant effect on the mean achievement of students as well as retention among students of high, medium and low ability in mathematics. However, cooperative learning strategy has no effect on the interaction of ability level and retention. Based on the results obtained, it was therefore recommended that the adoption of the use of cooperative learning strategy in the teaching and learning of mathematics in senior secondary schools be initiated, maintained and sustained for the benefit of senior secondary school students in Taraba State. Periodic Government sponsored in-service training in form of long vacation training programme, workshops, conferences and seminars on the nature, scope, and use of cooperative learning strategy should be organized for senior secondary school mathematics teachers in Taraba state.

Keywords: ability level, cooperative learning, mathematics achievement, retention

Procedia PDF Downloads 153

Authors: S. Yussuf Abdulmaliq

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Experiment was conducted for two years (2013 and 2014) at Ibrahim Badamasi Babangida University, Lapai, Teaching and Research Farm to study the effects of soil organic amendment types and rates on soil chemical fertility improvement, growth and yield of Amarathus cruentus in the southern guinea savannah, lapai, Niger state, Nigeria. Soil and manure samples were collected and analysed for physical and chemical components. The experiments were laid out in 3 x 4 factorial in a randomized complete block design (RCBD). Consisting of three (3) levels of soil amendment types (Poultry manure, goat manure and cowdung) and four (4) levels of amendment rates (0, 6, 12 and 18 t ha-1). Data collected include plant height/plant (cm), number of leaves/plant, leaf area/ plant (cm2) at 2, 4, 6 and 8WAT, fresh vegetable yield/plant, fresh vegetable yield/plot and fresh vegetable yield in tons ha-1. The result obtained showed that, Amaranthus cruentus height, number of leaves and leaf area were not significantly affected by the type of organic amendment and rates at 2WAT in 2013 and 2014 cropping seasons. However, at 4, 6 and 8 WAT, significant differences were observed among the types of amendment and their rates. Application of poultry manure as soil amendment supported taller, large number of leaves and wider leaf area, and higher marketable vegetable yield in 2013 and 2014 cropping seasons (Pα 0.05) which was closely followed by goat manure in the two (2) cropping seasons. In addition, the application of 18 t ha-1 was superior to 12, 6 and the control by producing tallest amaranthus plants, higher number of leaves, wider leaf area and higher marketable vegetable yield in 2013 and 2014 cropping seasons (Pα 0.05). In conclusion, the use of 18 t ha-1poultry manure is therefore recommended as soil amendment for Amaranthus cruentus in southern guinea savannah of Nigeria.

Keywords: Amaranthus cruentus, cowdung, goat manure, poultry manure, soil amendment

Procedia PDF Downloads 366

Authors: P. Mambanga, T. G. Tshitangano, H. Akinsola

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Background: Unintended pregnancies constitute a most serious public health challenge to women to an extent that they sometimes end in illegal abortions resulting in adverse consequences. However, the introduction of emergency contraception has served as the last chance for women to avoid unintended pregnancies, though, in countries like Zimbabwe the cause for underutilisation of emergency contraception has been hardly investigated. Purpose: The main purpose of this study was to assess the knowledge, attitude and practice of female students regarding emergency contraception among in preventing unintended pregnancy. Methodology: A quantitative approach using descriptive cross-sectional survey design was conducted among 319 stratified random sampled female university students of Midland State University, Zimbabwe. Self-administered close-ended questionnaire was used to collect the data. To ensure validity, the development of the instrument was guided by a wide range of literature and the inputs of experts. The instrument was retested for reliability and the responses will be comparing using Cronbach’s alpha which yielded high reliability alpha (α) value of 0.84. Data was coded and entered into a computer using Microsoft Excel 2010 and analysed using Statistical Package for Social Scientists (SPSS) version 22.0. Descriptive statistics were used to analyse data in the form of cross tabulation and the results were presented in table, graphs and pie charts. Results: The results indicated that apart from all sources of information about EC, mass media has shown to be the most famous. Although female students knows about EC, the knowledge about effective level and correct use of EC poor. The attitudes of female students at MSU are unfavourable for EC as they gave reasons like EC promotes promiscuity and it can pose risk. The practice of EC at MSU is low with only 47% of respondents said they have once use EC. Conclusion and recommendation: The study concluded the lack of actual knowledge about EC which has directly influenced attitudes and practices. The study concluded that there MSU female students has fair knowledge about EC which has resulted in negative and attitudes towards EC with few EC practices. The study, therefore, recommends the adoption and use of Health Belief Model approach in promoting the young to use EC to prevent unwanted pregnancies.

Keywords: emergency contraception, knowledge, attitude, practice, female students

Procedia PDF Downloads 231

Authors: Dmitry Lukyanov, Sergey Shevchenko, Alexander Kukaev

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Modern MEMS gyroscopes have strengthened their position in motion control systems and have led to the creation of tactical grade sensors (better than 15 deg/h). This was achieved by virtue of the success in micro- and nanotechnology development, cooperation among international experts and the experience gained in the mass production of MEMS gyros. This production is knowledge-intensive, often unique and, therefore, difficult to develop, especially due to the use of 3D-technology. The latter is usually associated with manufacturing of inertial masses and their elastic suspension, which determines the vibration and shock resistance of gyros. Today, consumers developing highly dynamic objects or objects working under extreme conditions require the gyro shock resistance of up to 65 000 g and the measurement range of more than 10 000 deg/s. Such characteristics can be achieved by solid-state gyroscopes (SSG) without inertial masses or elastic suspensions, which, for example, can be constructed with molecular kinetics of bulk or surface acoustic waves (SAW). Excellent effectiveness of this sensors production and a high level of structural integration provides basis for increased accuracy, size reduction and significant drop in total production costs. Existing principles of SAW-based sensors are based on the theory of SAW propagation in rotating coordinate systems. A short introduction to the theory of a gyroscopic (Coriolis) effect in SAW is provided in the report. Nowadays more and more applications require passive and wireless sensors. SAW-based gyros provide an opportunity to create one. Several design concepts incorporating reflective delay lines were proposed in recent years, but faced some criticism. Still, the concept is promising and is being of interest in St. Petersburg Electrotechnical University. Several experimental models were developed and tested to find the minimal configuration of a passive and wireless SAW-based gyro. Structural schemes, potential characteristics and known limitations are stated in the report. Special attention is dedicated to a novel method of a FEM modeling with piezoelectric and gyroscopic effects simultaneously taken into account.

Keywords: FEM simulation, gyroscope, OOFELIE, surface acoustic wave, wireless sensing

Procedia PDF Downloads 362

Authors: Krishmali N. Ekanayake, Brendan J. Holland, Colin J. Barrow, Rick Wood

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Globally, more than one-third of all food produced is lost or wasted, equating to 1.3 billion tonnes per year. Around 31.2 million tonnes of food waste are generated across the production, supply, and consumption chain in Australia. Generally, the food waste management processes adopt environmental-friendly and more sustainable approaches such as composting, anerobic digestion and energy implemented technologies. However, unavoidable, and non-recyclable food waste ends up as landfilling and incineration that involve many undesirable impacts and challenges on the environment. A biorefinery approach contributes to a waste-minimising circular economy by converting food and other organic biomass waste into valuable outputs, including feeds, nutrition, fertilisers, and biomaterials. As a solution, Green Eco Technologies has developed a food waste treatment process using WasteMaster system. The system uses charged oxygen and moderate temperatures to convert food waste, without bacteria, additives, or water, into a virtually odour-free, much reduced quantity of reusable residual material. In the context of a biorefinery, the WasteMaster dries and mills food waste into a form suitable for storage or downstream extraction/separation/concentration to create products. The focus of the study is to determine the nutritional composition of WasteMaster processed residue to potential develop aquafeed ingredients. The global aquafeed industry is projected to reach a high value market in future, which has shown high demand for the aquafeed products. Therefore, food waste can be utilized for aquaculture feed development by reducing landfill. This framework will lessen the requirement of raw crops cultivation for aquafeed development and reduce the aquaculture footprint. In the present study, the nutritional elements of processed residue are consistent with the input food waste type, which has shown that the WasteMaster is not affecting the expected nutritional distribution. The macronutrient retention values of protein, lipid, and nitrogen free extract (NFE) are detected >85%, >80%, and >95% respectively. The sensitive food components including omega 3 and omega 6 fatty acids, amino acids, and phenolic compounds have been found intact in each residue material. Preliminary analysis suggests a price comparability with current aquafeed ingredient cost making the economic feasibility. The results suggest high potentiality of aquafeed development as 5 to 10% of the ingredients to replace/partially substitute other less sustainable ingredients across biorefinery setting. Our aim is to improve the sustainability of aquaculture and reduce the environmental impacts of food waste.

Keywords: biorefinery, ffood waste residue, input, wasteMaster

Procedia PDF Downloads 61

Authors: J. Ritonja

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Available commercial applications of power system stabilizers assure optimal damping of synchronous generator’s oscillations only in a small part of operating range. Parameters of the power system stabilizer are usually tuned for the selected operating point. Extensive variations of the synchronous generator’s operation result in changed dynamic characteristics. This is the reason that the power system stabilizer tuned for the nominal operating point does not satisfy preferred damping in the overall operation area. The small-signal stability and the transient stability of the synchronous generators have represented an attractive problem for testing different concepts of the modern control theory. Of all the methods, the adaptive control has proved to be the most suitable for the design of the power system stabilizers. The adaptive control has been used in order to assure the optimal damping through the entire synchronous generator’s operating range. The use of the adaptive control is possible because the loading variations and consequently the variations of the synchronous generator’s dynamic characteristics are, in most cases, essentially slower than the adaptation mechanism. The paper shows the development and the application of the self-tuning power system stabilizer based on recursive least square identification method and linear quadratic regulator. Identification method is used to calculate the parameters of the Heffron-Phillips model of the synchronous generator. On the basis of the calculated parameters of the synchronous generator’s mathematical model, the synthesis of the linear quadratic regulator is carried-out. The identification and the synthesis are implemented on-line. In this way, the self-tuning power system stabilizer adapts to the different operating conditions. A purpose of this paper is to contribute to development of the more effective power system stabilizers, which would replace currently used linear stabilizers. The presented self-tuning power system stabilizer makes the tuning of the controller parameters easier and assures damping improvement in the complete operating range. The results of simulations and experiments show essential improvement of the synchronous generator’s damping and power system stability.

Keywords: adaptive control, linear quadratic regulator, power system stabilizer, recursive least square identification

Procedia PDF Downloads 240

Authors: E. Knisel, H. Rupprich, A. Heissel

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Health Literacy is defined as the degree to which people have the capacity to obtain and understand information to make health decisions. Illustrated are three levels of health literacy: (1) Functional literacy refers to the transmission of information about e. g. physical activity and nutrition; (2) interactive literacy implies the development of personal and social skills to adopt health-related behaviour and (3) critical health literacy indicates advanced cognitive skills connected with personal empowerment to critically analyse health information, to define self-determined goals and taking action in various situations accordingly. The achievement of the third level refers to self-determination and autonomy which should be outcomes of exercise programs for overweight children as health-related behaviour change will occur and persist if it is autonomously motivated. Method: We adopted a quasi-experimental design with group (autonomy supportive coaching, control) and session (pre-test, intervention, post-test, and follow-up-test). Overweight and obese children and adolescents at the age of 8-14 years (N=40) received a 6-month (20 sessions) exercise program with autonomy supportive coaching implemented by the coaches and sandwiched between pre-test and post-test. All participants (N=92) completed the German version of the Basic Needs Satisfaction Scale Sport and Exercise. Additionally, we assessed the engagement in the exercise program by the MVPA (Moderate-to-Vigorous Physical Activity) and by the adherence and drop-out-rate. Results: Participants in the intervention group perceived their autonomy as moderate in the post-test and the follow-up-test. However, the psychological intervention failed to develop a high autonomy, as both groups show moderate perceived autonomy from the pre-test to the post-test. Participants in the intervention group were higher engaged in MVPA in the exercise program and they attend the program more regularly. Discussion: Young overweight and obese children and adolescents can acquire autonomy using autonomy supporting coaching. However, research identifying the extent they achieve critical health literacy is required to implement an autonomy-supportive coaching style into exercise programs for this target group.

Keywords: autonomy support, coaching, health literacy, health promotion

Procedia PDF Downloads 484

Authors: Sarath Chandran Nair S, Srinivas Kodati, Vasudevan R, Asraff A. K

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Spacecrafts generally employ liquid propulsion for their attitude and orbital maneuvers or raising it from geo-transfer orbit to geosynchronous orbit. Liquid propulsion systems use either mono-propellant or bi-propellants for generating thrust. These propellants are generally stored in either spherical tanks or cylindrical tanks with spherical end domes. The propellant tanks are provided with a propellant acquisition system/propellant management device along with vanes and their conical mounting structure to ensure propellant availability in the outlet for thrust generation even under a low/zero-gravity environment. Slosh is the free surface oscillations in partially filled containers under external disturbances. In a spacecraft, these can be due to control forces and due to varying acceleration. Knowledge of slosh and its effect due to internals is essential for understanding its stability through control stability studies. It is mathematically represented by a pendulum-mass model. It requires parameters such as slosh frequency, damping, sloshes mass and its location, etc. This paper enumerates various numerical and experimental methods used for evaluating the slosh parameters required for representing slosh. Numerical methods like finite element methods based on linear velocity potential theory and computational fluid dynamics based on Reynolds Averaged Navier Stokes equations are used for the detailed evaluation of slosh behavior in one of the spacecraft propellant tanks used in an Indian space mission. Experimental studies carried out on a scaled-down model are also discussed. Slosh parameters evaluated by different methods matched very well and finalized their dispersion bands based on experimental studies. It is observed that the presence of internals such as propellant management devices, including conical support structure, alters slosh parameters. These internals also offers one order higher damping compared to viscous/ smooth wall damping. It is an advantage factor for the stability of slosh. These slosh parameters are given for establishing slosh margins through control stability studies and finalize the spacecraft control system design.

Keywords: control stability, propellant tanks, slosh, spacecraft, slosh spacecraft

Procedia PDF Downloads 238

Authors: Rachel Koshy, Nazrila Hairizan Bt. Nasir, Samsiah Bt. Awang, Kamaliah Bt. Mohamad Noh

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Malaysia collaborated as a ‘trailblazer’ country with PHCPI (Primary Health Care Performance Initiative) to populate the Primary Health Care (PHC) Vital Signs Profile (VSP) for the country. The PHC VSP provides an innovative snapshot of the primary health care system's performance. Four domains were assessed: system financing, system capacity, system performance, and system equity, and completed in 2019. There were two phases using a mixed method study design. The first phase involved a quantitative study, utilising existing secondary data from national and international sources. In the case of unavailability of data for any indicators, comparable alternative indicators were used. The second phase was a mixed quantitative-qualitative approach to measure the functional capacity based on governance and leadership, population health needs, inputs, population health management, and facility organisation and management. PHC spending constituted 35% of overall health spending in Malaysia, with a per capita PHC spending of $152. The capacity domain was strong in the three subdomains of governance and leadership, information system, and funds management. The two subdomains of drugs & supplies and facility organisation & management had low scores, but the lowest score was in empanelment of the population under the population health management. The PHC system performed with an access index of 98%, quality index of 84%, and service coverage of 62%. In the equity domain, there was little fluctuation in the coverage of reproductive, maternal, newborn, and child health services by mother’s level of education and under-five child mortality between urban and rural areas. The public sector was stronger in the capacity domain as compared to the private sector. This is due to the different financing, organisational structures, and service delivery mechanism. The VSP has identified areas for improvement in the effort to provide high-quality PHC for the population. The gaps in PHC can be addressed through the system approach and the positioning of public and private primary health care delivery systems.

Keywords: primary health care, health system, system domains, vital signs profile

Procedia PDF Downloads 122

Authors: L. N. P. Wedikandage, Mohamed Razmi Zahir

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Technology is a global imperative because of its contributions to human existence and because it has improved global socioeconomic relations. As a result, the mobile phone has become the most important mode of communication today. Smartphones, Internet-enabled devices with built-in computer software and applications, are one of the most significant inventions of the twenty-first century. Technology is advantageous to many people, especially those involved in education. It is an important learning tool for today's schoolchildren. It enables students to access online learning platforms and course resources and interact digitally. Senior secondary students, in particular, have some of the most expensive and sophisticated mobile phones, tablets, and iPads capable of connecting to the internet and various social media platforms, other websites, and so on. At present, the use of mobile phones' potential for effective teaching and learning is growing. This is due to the benefits of mobile learning, including the ability to share knowledge without any limits in space or Time and the capacity to facilitate the development of critical thinking, participatory learning, problem-solving, and the development of lifelong communication skills. However, it is yet unclear how mobile devices may affect education and how they may affect opportunities for learning. As a result, the purpose of this research was to ascertain the relationship between mobile phone usage and the academic Performance of secondary-level students at an international school in Sri Lanka. The study's sample consisted of 523 secondary-level students from an international school, ranging from Form 1 to Upper 6. For the study, a survey research design and questionnaires were used. Google Forms was used to create the students' survey. There were three hypotheses tested to find out the relationship between mobile phone usage and academic preference. The findings show that there is a positive relationship between mobile phone usage and academic performance among secondary school students (the number of students obtaining simple passes is significantly higher when mobile phones are being used for more than 7 hours), no relationship between mobile phone usage and academic performance among secondary school students of different parents' occupations, and a relationship between the frequency of mobile phone usage and academic performance among secondary school students.

Keywords: mobile phone, academic performance, secondary level, international schools

Procedia PDF Downloads 78

Authors: José Álvarez Pérez, Ramón García Cedeño, Gerardo Fajardo-San Miguel, Jorge H. Chávez Gómez, Franco A. Carpio Santamaría, Milena Mesa Lavista

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The uniaxial compressive strength and modulus of elasticity in hollow concrete block masonry (HCBM) represent key mechanical properties for structural design considerations. These properties are obtained through experimental tests conducted on prisms or wallettes and depend on various factors, with the HCB contributing significantly to overall strength. One influential factor in the compressive behaviour of masonry is the thickness and method of mortar placement. Mexican regulations stipulate mortar placement over the entire net area (full-shell) for strength computation based on the gross area. However, in professional practice, there's a growing trend to place mortar solely on the lateral faces. Conversely, the United States of America standard dictates mortar placement and computation over the net area of HCB. The Canadian standard specifies mortar placement solely on the lateral face (Face-Shell-Bedding), where computation necessitates the use of the effective load area, corresponding to the mortar's placement area. This research aims to evaluate the influence of different mortar placement methods on the axial compression behaviour of HCBM. To achieve this, an experimental campaign was conducted, including: (1) 10 HCB specimens with mortar on the entire net area, (2) 10 HCB specimens with mortar placed on the lateral faces, (3) 10 prisms of 2-course HCB under axial compression with mortar in full-shell, (4) 10 prisms of 2-course HCB under axial compression with mortar in face-shell-bedding, (5) 10 prisms of 3-course HCB under axial compression with mortar in full-shell, (6) 10 prisms of 3-course HCB under axial compression with mortar in face-shell-bedding, (7) 10 prisms of 4-course HCB under axial compression with mortar in full-shell, and, (8) 10 prisms of 4-course HCB under axial compression with mortar in face-shell-bedding. A combination of sulphur and fly ash in a 2:1 ratio was used for the capping material, meeting the average compressive strength requirement of over 35 MPa as per NMX-C-036 standards. Additionally, a mortar with a strength of over 17 MPa was utilized for the prisms. The results indicate that prisms with mortar placed over the full-shell exhibit higher strength compared to those with mortar over the face-shell-bedding. However, the elastic modulus was lower for prisms with mortar placement over the full-shell compared to face-shell bedding.

Keywords: masonry, hollow concrete blocks, mortar placement, prisms tests

Procedia PDF Downloads 54

Authors: M. Tammaro, S. Manzo, J. Rimauro, A. Salluzzo, S. Schiavo

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The solar photovoltaic (PV) modules are considered to have a negligible environmental impact compared to the fossil energy. Therefore also the waste management and the corresponding potential environmental hazard needs to be considered. The case of the photovoltaic panel is unique because the time lag from the manufacturing to the decommissioning as waste usually takes 25-30 years. Then the environmental hazard associated with end life of PV panels has been largely related to their metal contents. The principal concern regards the presence of heavy metals as Cd in thin film (TF) modules or Pb and Cr in crystalline silicon (c-Si) panels. At the end of life of PV panels, these dangerous substances could be released in the environment, if special requirements for their disposal are not adopted. Nevertheless, in literature, only a few experimental study about metal emissions from silicon crystalline/thin film panels and the corresponding environmental effect are present. As part of a study funded by the Italian national consortium for the waste collection and recycling (COBAT), the present work was aimed to analyze experimentally the potential release into the environment of hazardous elements, particularly metals, from PV waste. In this paper, for the first time, eighteen releasable metals a large number of photovoltaic panels, by c-Si and TF, manufactured in the last 30 years, together with the environmental effects by a battery of ecotoxicological tests, were investigated. Leaching tests are conducted on the crushed samples of PV module. The test is conducted according to Italian and European Standard procedure for hazard assessment of the granular waste and of the sludge. The sample material is shaken for 24 hours in HDPE bottles with an overhead mixer Rotax 6.8 VELP at indoor temperature and using pure water (18 MΩ resistivity) as leaching solution. The liquid-to-solid ratio was 10 (L/S=10, i.e. 10 liters of water per kg of solid). The ecotoxicological tests were performed in the subsequent 24 hours. A battery of toxicity test with bacteria (Vibrio fisheri), algae (Pseudochirneriella subcapitata) and crustacea (Daphnia magna) was carried out on PV panel leachates obtained as previously described and immediately stored in dark and at 4°C until testing (in the next 24 hours). For understand the actual pollution load, a comparison with the current European and Italian benchmark limits was performed. The trend of leachable metal amount from panels in relation to manufacturing years was then highlighted in order to assess the environmental sustainability of PV technology over time. The experimental results were very heterogeneous and show that the photovoltaic panels could represent an environmental hazard. The experimental results showed that the amounts of some hazardous metals (Pb, Cr, Cd, Ni), for c-Si and TF, exceed the law limits and they are a clear indication of the potential environmental risk of photovoltaic panels "as a waste" without a proper management.

Keywords: photovoltaic panel, environment, ecotoxicity, metals emission

Procedia PDF Downloads 257

Authors: Imran Khan Swati, Mohammad Younas

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This work aims to explore the potential applications of polymeric hydrophobic membranes and green ionic liquids (ILs). Protic and aprotic ILs were synthesized in the lab., characterized, and tested for CO₂/N₂ and CO₂/CH₄ separation using hydrophobic polymeric membranes via supported ionic liquid membrane (SILM). ILs were verified by FTIR spectroscopy. The SILMs were stable at room temperature up to 0.5 MPa. For CO₂, [BSmim][tos] had the greatest coefficient of solubility and permeability, along with all ILs. At 0.5 MPa, IL [BSmim][tos] was found with a selectivity of 56.2 and 47.5 for pure CO₂/N₂ and CO₂/CH₄, respectively. The ILs synthesized for this study are rated as [BSmim][tos]>[BSmpy][tos]>[Bmim][Cl]>[Bpy][Cl] based on their SILM separation performance. Furthermore, high values of selectivity of [BSmim][tos] and [BSmpy][tos] support the use of ILs for CO₂ separation using SILMs. The study was extended to synthesize and test the ammonium-based ILs, [2-HEA][f] and [2-HEA][Hs]. These ILs achieved 50 % less selectivity for CO₂/N₂ as compared to [BSmim][tos] and [BSmpy][tos]. Nevertheless, the permeability of CO₂ achieved with [2-HEA][f] and [2-HEA][Hs] is more than 20 times higher than the [BSmim][tos] and [BSmpy][tos]. Later, the CO₂/N₂ permeability and selectivity study was extended using a flat sheet membrane contactor with recirculated IL. The contact angle effects, liquid entry pressure (LEP), initial CO₂ concentration, and type of solvents and membrane material on the CO₂ capture efficiency and membrane wetting in the post-combustion capture (PCC) process have been experimentally investigated and evaluated. Polytetrafluoroethylene (PTFE) has shown the most hydrophobic property with 6-170 loss in the contact angle. Furthermore, [Omim][BF4] and [Bmim][BF6] have exhibited only 5-8 % loss in LEP using PTFE membrane support. The CO₂ capture efficiency has been achieved as 80.8-99.8 % in different combinations of ILs and membrane support, keeping all other variables constant. While increasing CO₂ concentration from 15 to 45 % vol., an increase of nearly three folds in the CO₂ mass transfer flux was observed. The combination of [Omim][BF4] and PTFE membrane witnessed good long-term stability with only a 20 % loss in CO₂ capture efficiency in 480 min of continuous operation. A 3- D simulation model for non-dispersive solvent absorption in membrane contactors provides insight into the optimum design of a separation system for a specific application minimizing the overall cost and making the process environment-friendly.

Keywords: Post-combustion CO2 capture, membrane synthesis, process development, permeability and selectivity, ionic liquids

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Authors: Apurva Sapra

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The aim of this research was to study and compare the nature of expected, feared and hoped-for selves in institutionalized adolescent boys in two residential settings – an observation home with children in conflict with the law, and a children’s home with children in need of care and protection. The study uses a concurrent mixed methods design, in which eight adolescent boys from each group, aged 13-17, were asked to respond to a questionnaire, followed by an in-depth interview. The questionnaire looked into the total scores on current, probable and hoped-for/feared positive and negative self-descriptors. Possible selves of both groups were found to be influenced by their unique histories, such as with their experience of violence, interaction with the police and emphasis given on education. Expected selves and hoped-for selves were similar within the two groups. However, they were more concrete and attainable in the observation home and more ambitious in the children’s home. Quantitative results showed that on the positive self-descriptors, the participants in the observation home had a slightly lower total score on the current parameter as on the probable and hoped-for parameters. The participants in the children’s home showed similar results on current and probable positive self-descriptors, with higher scores on the hoped-for parameter. For most of the negative self-descriptors, the current score for the observation home group was lower than the expected score, and for the children’s home group, they were feared slightly more than they were expected. Along with the nature of possible selves, the study also looked into threats and support to desired and feared possible selves, as well as strategies to attain the desired possible selves and avoid feared possible selves. While threats to possible selves were identified as external and internal in both groups, the participants in the children’s home tended to identify threats as external. The categories of support were similar across the two groups, although the nature of support provided differed. Strategies adopted by participants in the observation home could be clearly divided as past, present and future strategies, while those adopted by participants in the children’s home had an overlap with past and future strategies. The institution was perceived as having a negative influence for the future in the observation home group, but positive in the children’s home group. Limitations of the study and recommendations for future research, policy setting and the counselling profession are discussed.

Keywords: adolescents, expected self, feared self, hoped-for self, institutions, possible selves

Procedia PDF Downloads 228

Authors: Azam Zare

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Separation flow control for performance enhancement over airfoils at high incidence angle has become an increasingly important topic. This work details the characteristics of an efficient feedback control of the turbulent subsonic flow over NACA23012 airfoil using forced reduced‐order model based on the proper orthogonal decomposition/Galerkin projection and perturbation method on the compressible Reynolds Averaged Navier‐Stokes equations. The forced reduced‐order model is used in the optimal control of the turbulent separated flow over a NACA23012 airfoil at Mach number of 0.2, Reynolds number of 5×106, and high incidence angle of 24° using blowing/suction controlling jets. The Spallart-Almaras turbulence model is implemented for high Reynolds number calculations. The main shortcoming of the POD/Galerkin projection on flow equations for controlling purposes is that the blowing/suction controlling jet velocity does not show up explicitly in the resulting reduced order model. Combining perturbation method and POD/Galerkin projection on flow equations introduce a forced reduced‐order model that can predict the time-varying influence of the blowing/suction controlling jet velocity. An optimal control theory based on forced reduced‐order system is used to design a control law for a nonlinear reduced‐order model, which attempts to minimize the vorticity content in the turbulent flow field over NACA23012 airfoil. Numerical simulations were performed to help understand the behavior of the controlled suction jet at 12% to 18% chord from leading edge and a pair of blowing/suction jets at 15% to 18% and 24% to 30% chord from leading edge, respectively. Analysis of streamline profiles indicates that the blowing/suction jets are efficient in removing separation bubbles and increasing the lift coefficient up to 22%, while the perturbation method can predict the flow field in an accurate Manner.

Keywords: flow control, POD, Galerkin projection, separation

Procedia PDF Downloads 146

Authors: Regina Tedjasulaksana, Maria Martina Nahak, A. A. Gede Agung, Ni Made Widhiasti

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Strategic effort to realize the empowerment of community in school is through the peer group approach so that it needs to choose the students who are trained as the’ little dentist’ in order to have the cognitive and skills to participate in the school dental health effort (UKGS) program, such as providing oral health education to the other students. Aim: To assessed the effectiveness of peer group approach to enhance the oral health knowledge level of schoolchildren at primary school in Klungkung, Bali. Methods: Experimental study using the pre-post test without control group design. The differences of knowledge levels, tooth brushing behavior and oral hygiene status (using PHP-M index) of 10 students before and after trained as the little dentists were analyzed using paired t-test. The correlations between knowledge level and tooth brushing behavior and correlations between tooth brushing behavior and oral hygiene before and after trained as the little dentists were analyzed using Spearman. Furthermore, the trained little dentists provide oral health education to 102 students of grade 1 to 5 at their school once a week for 3 months. The students’ knowledge level scores of each grade were taken every 21 days as many as three times The difference of it was analyzed using Repeated Measured. Result: The mean scores among all little dentists before and after training for each of knowledge level were each 63.05 + 5.62 and 85.00 + 7.81, tooth brushing behavior were each 31.00 + 14.49 and 100.00 + 0.00 and oral hygiene status using PHP-M index were each 32.80 + 10.17 and 11.40 + 8.01. The knowledge level, tooth brushing behavior and oral hygiene status of 10 students before and after trained as the little dentists were different significantly (p<0.05). Before and after trained as the little dentists it showed that significant correlations between knowledge level with tooth brushing behavior (p<0.05) and significant correlations between tooth brushing behavior and oral hygiene (p<0.05). The mean scores of knowledge level among all students before (pre-test) and after (post-test (1),(2),(3)) getting oral health education from little dentists for each, of grade 1 were 40.00 + 17.97; 67.85 + 18.88; 81.72 +26.48 and 70.00 + 22.87, grade 2 were 40.00 + 17.97; 67.85 + 18.88; 81.72 + 26.48 and 70.00 + 22.87, grade 3 were 65.83 + 23.94; 72.50 + 26.08; 80.41 + 24.93 and 83.75 + 19.74, grade 4 were 88.57 + 12.92; 90.71 + 9.97; 92.85 + 10.69 and 93.57 + 6.33 and grade 5 were 86.66 + 13.40; 93.33 + 9.16; 94.16 + 10.17 and 98.33 + 4.81. The students’ knowledge level of grade 1,2 and 3 before and after getting oral health education from little dentists showed significant different (p<0.05), meanwhile there was no significant different on grade 4 and 5 (p<0.05) although mean scores showed an increase. Conclusion: Peer group approach can be used to enhance the oral health knowledge level of schoolchildren at primary school in Klungkung, Bali.

Keywords: small dentists, oral health, peer group approach, school children

Procedia PDF Downloads 421

Authors: Ozcan B., Koca B., Tuzcuoglu E., Cavusoglu S., Efe A., Bayraktar S.

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A washing machine is mainly used for removing any types of dirt and stains and also eliminating malodorous substances from textile surfaces. Stains originate from various sources from the human body to environmental contamination. Therefore, there are various methods for removing them. They are roughly classified into four different groups: oily (greasy) stains, particulate stains, enzymatic stains and bleachable (oxidizable) stains. Oily stains on clothes surfaces are a common result of being in contact with organic substances of the human body (e.g. perspiration, skin shedding and sebum) or by being exposed to an oily environmental pollutant (e.g. oily foods). Studies showed that human sebum is major component of oily soil found on the garments, and if it is aged under the several environmental conditions, it can generate obstacle yellow stains on the textile surface. In this study, a parametric study was carried out to investigate the key factors affecting the cleaning performance (specifically sebum removal performance) of a washing machine. These parameters are mechanical agitation percentage of tumble, consumed water and total washing period. A full factorial design of the experiment is used to capture all the possible parametric interactions using Minitab 2021 statistical program. Tests are carried out with commercial liquid detergent and 2 different types of sebum-soiled cotton and cotton + polyester fabrics. Parametric results revealed that for both test samples, increasing the washing time and the mechanical agitation could lead to a much better removal result of sebum. However, for each sample, the water amount had different outcomes. Increasing the water amount decreases the performance of cotton + polyester fabrics, while it is favorable for cotton fabric. Besides this, it was also discovered that the type of textile can greatly affect the sebum removal performance. Results showed that cotton + polyester fabrics are much easier to clean compared to cotton fabric

Keywords: laundry, washing machine, low-temperature washing, cold wash, washing efficiency index, sustainability, cleaning performance, stain removal, oily soil, sebum, yellowing

Procedia PDF Downloads 134

Authors: Dieudonne Uwizeye

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Introduction: Diarrhoea is one of the major causes of morbidity and mortality among communities living in urban informal settlements of developing countries. It is assumed that mountainous environment introduces variations of the burden among residents of the same settlements. Design and Objective: A cross-sectional study was done in Kigali to explore the effect of mountainous informal settlements on diarrhoea risk variations. Data were collected among 1,152 households through household survey and transect walk to observe the status of sanitation. The outcome variable was the incidence of diarrhoea among household members of any age. The study used the most knowledgeable person in the household as the main respondent. Mostly this was the woman of the house as she was more likely to know the health status of every household member as she plays various roles: mother, wife, and head of the household among others. The analysis used cross tabulation and logistic regression analysis. Results: Results suggest that risks for diarrhoea vary depending on home location in the settlements. Diarrhoea risk increased as the distance from the road increased. The results of the logistic regression analysis indicate the adjusted odds ratio of 2.97 with 95% confidence interval being 1.35-6.55 and 3.50 adjusted odds ratio with 95% confidence interval being 1.61-7.60 in level two and three respectively compared with level one. The status of sanitation within and around homes was also significantly associated with the increase of diarrhoea. Equally, it is indicated that stable households were less likely to have diarrhoea. The logistic regression analysis indicated the adjusted odds ratio of 0.45 with 95% confidence interval being 0.25-0.81. However, the study did not find evidence for a significant association between diarrhoea risks and household socioeconomic status in the multivariable model. It is assumed that environmental factors in mountainous settings prevailed. Households using the available public water sources were more likely to have diarrhoea in their households. Recommendation: The study recommends the provision and extension of infrastructure for improved water, drainage, sanitation and wastes management facilities. Equally, studies should be done to identify the level of contamination and potential origin of contaminants for water sources in the valleys to adequately control the risks for diarrhoea in mountainous urban settings.

Keywords: urbanisation, diarrhoea risk, mountainous environment, urban informal settlements in Rwanda

Procedia PDF Downloads 164

Authors: Sandra Thompson, Paul Dervan

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Ireland’s first Technological University (TU Dublin) was established on 1st January 2019, and its creation is an exciting new milestone in Irish Higher Education. TU Dublin is now Ireland’s biggest University supporting 29,000 students across three campuses with 3,500 staff. The University aspires to create work-ready graduates who are socially responsible, open-minded global thinkers who are ambitious to change the world for the better. As graduates, they will be enterprising and daring in all their endeavors, ready to play their part in transforming the future. Feedback from Irish employers and students coupled with evidence from other authoritative sources such as the World Economic Forum points to a need for greater focus on the development of students’ employability skills as they prepare for today’s work environment. Moreover, with an increased focus on Universal Design for Learning (UDL) and inclusiveness, there is recognition that students are more than a numeric grade value. Robust grading systems have been developed to track a student’s performance around discipline knowledge but there is little or no global consensus on a definition of transversal skills nor on a unified framework to assess transversal skills. Education and industry sectors are often assessing one or two skills, and some are developing their own frameworks to capture the learner’s achievement in this area. Technological University Dublin (TU Dublin) have discovered and implemented a framework to allow students to develop, assess and record their transversal skills using transformative learning theory. The model implemented is an adaptation of Student Transformative Learning Record - STLR which originated in the University of Central Oklahoma (UCO). The purpose of this paper therefore, is to examine the views of students, staff and employers in the context of deploying a Transformative Learning model within the University to assess transversal skills. It will examine the initial impact the transformative learning model is having socially, personally and on the University as an organization. Crucially also, to identify lessons learned from the deployment in order to assist other Universities and Higher Education Institutes who may be considering a focused adoption of Transformative Learning to meet the challenge of preparing students for today’s work environment.

Keywords: assessing transversal skills, higher education, transformative learning, students

Procedia PDF Downloads 123

Authors: Kaihong Yu, Tetsui Yamashita, Shigeaki Shingyochi, Kazuo Matsumoto, Makoto Ohta

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During cardiac ablation, high power delivery for deeper lesion formation is limited by electrode-tissue interface overheating which can cause serious complications such as thrombus. To prevent this overheating, temperature control and open irrigation are often used. In temperature control, radiofrequency generator is adjusted to deliver the maximum output power, which maintains the electrode temperature at a target temperature (commonly 55°C or 60°C). Then the electrode-tissue interface temperature is also limited. The electrode temperature is a result of heating from the contacted tissue and cooling from the surrounding blood. Because the cooling from blood is decreased under conditions of low blood flow, the generator needs to decrease the output power. Thus, temperature control cannot deliver high power under conditions of low blood flow. In open irrigation, saline in room temperature is flushed through the holes arranged in the electrode. The electrode-tissue interface is cooled by the sufficient environmental cooling. And high power delivery can also be done under conditions of low blood flow. However, a large amount of saline infusions (approximately 1500 ml) during irrigation can cause other serious complication. When open irrigation cannot be used under conditions of low blood flow, a new overheating prevention may be required. The authors have proposed a new electrode cooling method by making the catheter vibrating. The previous work has introduced that the vibration can make a cooling effect on electrode, which may result form that the vibration could increase the flow velocity around the catheter. The previous work has also proved that increasing vibration frequency can increase the cooling by vibration. However, the effect of the vibration amplitude is still unknown. Thus, the present study investigated the effect of vibration amplitude on tissue temperature and lesion size. An agar phantom model was used as a tissue-equivalent material for measuring tissue temperature. Thermocouples were inserted into the agar to measure the internal temperature. Porcine myocardium was used for lesion size measurement. A normal ablation catheter was set perpendicular to the tissue (agar or porcine myocardium) with 10 gf contact force in 37°C saline without flow. Vibration amplitude of ± 0.5, ± 0.75, and ± 1.0 mm with a constant frequency (31 Hz or 63) was used. A temperature control protocol (45°C for agar phantom, 60°C for porcine myocardium) was used for the radiofrequency applications. The larger amplitude shows the larger lesion sizes. And the higher tissue temperatures in agar phantom are also shown with the higher amplitude. With a same frequency, the larger amplitude has the higher vibrating speed. And the higher vibrating speed will increase the flow velocity around the electrode more, which leads to a larger electrode temperature decrease. To maintain the electrode at the target temperature, ablator has to increase the output power. With the higher output power in the same duration, the released energy also increases. Consequently, the tissue temperature will be increased and lead to larger lesion sizes.

Keywords: cardiac ablation, electrode cooling, lesion size, tissue temperature

Procedia PDF Downloads 364

Authors: Manjari Srivastsva, Ruta Vyas

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The research in the area of self leadership advocates employee/team empowerment. It is well understood that empowered employees would contribute more and better to their organizational outcomes. This research is a part of an ongoing larger research in the area of empowering leadership behavior. The present research aims to understand some of the antecedents to empowering behavior of leaders such that the organizations can focus on the right elements and invest in the appropriate areas during their leadership development activities. The research is exploratory field study. Sampling is purposive, employing triadic design i.e. a manager and two of his/her subordinates are selected for data collection. The total no. of respondents is 240, with 80 managers and 160 of their direct reports. Initially focus group interview was done and based on the inputs from focus group, quantitative data was collected personally by the researchers using questionnaire. The sample is drawn from seven professionally run organization including those of Indian origin as well as multi-national companies. This study proposes to explore the constituents of empowering behavior both from leaders’ and their subordinates’ perspective and also see the relationship between some of the personal variables of leaders as an antecedent to empowering behavior. Similarly, the study aims to explore the subordinates’ perspectives as an antecedent to empowering behavior. The relationship between antecedent variables and empowering behavior is tested for moderation employing organization culture. Exploratory and confirmatory factor analysis was done to establish the validity of the questionnaires. Further hierarchical regression analysis results revealed that organization based self-esteem and global self-esteem impact leaders’ empowering behavior and this relationship is further moderated by organization culture. Team members’ perspective showed higher importance for task characteristics and members' readiness from the point of view of empowerment. The relation between task characteristics and members’ readiness was not moderated by culture. The finding from this research may be utilized by professionals to guide organizations desiring rapid and sustainable growth, to develop leaders who empower their teams such that they act as leaders themselves and become stimulants for the growth of organizations.

Keywords: empowering behavior, team leaders, subordinates, self-esteem, organization culture, task characteristics, team members readiness

Procedia PDF Downloads 414

Authors: Loredana E. Nita, Aurica P. Chiriac, Elena Stoleru, Alina Diaconu, Tudorachi Nita

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Self-assembly processes are an attractive method to form new and complex structures between macromolecular compounds to be used for specific applications. In this context, intramolecular and intermolecular bonds play a key role during self-assembling processes in preparation of carrier systems of bioactive substances. Polyelectrolyte complexes (PECs) are formed through electrostatic interactions, and though they are significantly below of the covalent linkages in their strength, these complexes are sufficiently stable owing to the association processes. The relative ease way of PECs formation makes from them a versatile tool for preparation of various materials, with properties that can be tuned by adjusting several parameters, such as the chemical composition and structure of polyelectrolytes, pH and ionic strength of solutions, temperature and post-treatment procedures. For example, protein-polyelectrolyte complexes (PPCs) are playing an important role in various chemical and biological processes, such as protein separation, enzyme stabilization and polymer drug delivery systems. The present investigation is focused on evaluation of the PPC formation between a synthetic polypeptide (poly(aspartic acid) – PAS) and a natural protein (bovine serum albumin - BSA). The PPC obtained from PAS and BSA in different ratio was investigated by corroboration of various techniques of characterization as: spectroscopy, microscopy, thermo-gravimetric analysis, DLS and zeta potential determination, measurements which were performed in static and/or dynamic conditions. The static contact angle of the sample films was also determined in order to evaluate the changes brought upon surface free energy of the prepared PPCs in interdependence with the complexes composition. The evolution of hydrodynamic diameter and zeta potential of the PPC, recorded in situ, confirm changes of both co-partners conformation, a 1/1 ratio between protein and polyelectrolyte being benefit for the preparation of a stable PPC. Also, the study evidenced the dependence of PPC formation on the temperature of preparation. Thus, at low temperatures the PPC is formed with compact structure, small dimension and hydrodynamic diameter, close to those of BSA. The behavior at thermal treatment of the prepared PPCs is in agreement with the composition of the complexes. From the contact angle determination results the increase of the PPC films cohesion, which is higher than that of BSA films. Also, a higher hydrophobicity corresponds to the new PPC films denoting a good adhesion of the red blood cells onto the surface of PSA/BSA interpenetrated systems. The SEM investigation evidenced as well the specific internal structure of PPC concretized in phases with different size and shape in interdependence with the interpolymer mixture composition.

Keywords: polyelectrolyte – protein complex, bovine serum albumin, poly(aspartic acid), self-assembly

Procedia PDF Downloads 235

Authors: Ligang Wang, Theodoros Damartzis, Stefan Diethelm, Jan Van Herle, François Marechal

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Biogas production from anaerobic digestion of organic sludge from wastewater treatment as well as various urban and agricultural organic wastes is of great significance to achieve a sustainable society. Two upgrading approaches for cleaned biogas can be considered: (1) direct H₂ injection for catalytic CO₂ methanation and (2) CO₂ separation from biogas. The first approach usually employs electrolysis technologies to generate hydrogen and increases the biogas production rate; while the second one usually applies commercially-available highly-selective membrane technologies to efficiently extract CO₂ from the biogas with the latter being then sent afterward for compression and storage for further use. A straightforward way of utilizing the captured CO₂ is on-site catalytic CO₂ methanation. From the perspective of system complexity, the second approach may be questioned, since it introduces an additional expensive membrane component for producing the same amount of methane. However, given the circumstance that the sustainability of the produced biogas should be retained after biogas upgrading, renewable electricity should be supplied to drive the electrolyzer. Therefore, considering the intermittent nature and seasonal variation of renewable electricity supply, the second approach offers high operational flexibility. This indicates that these two approaches should be compared based on the availability and scale of the local renewable power supply and not only the technical systems themselves. Solid-oxide electrolysis generally offers high overall system efficiency, and more importantly, it can achieve simultaneous electrolysis of CO₂ and H₂O (namely, co-electrolysis), which may bring significant benefits for the case of CO₂ separation from the produced biogas. When taking co-electrolysis into account, two additional upgrading approaches can be proposed: (1) direct steam injection into the biogas with the mixture going through the SOE, and (2) CO₂ separation from biogas which can be used later for co-electrolysis. The case study of integrating SOE to a wastewater treatment plant is investigated with wind power as the renewable power. The dynamic production of biogas is provided on an hourly basis with the corresponding oxygen and heating requirements. All four approaches mentioned above are investigated and compared thermo-economically: (a) steam-electrolysis with grid power, as the base case for steam electrolysis, (b) CO₂ separation and co-electrolysis with grid power, as the base case for co-electrolysis, (c) steam-electrolysis and CO₂ separation (and storage) with wind power, and (d) co-electrolysis and CO₂ separation (and storage) with wind power. The influence of the scale of wind power supply is investigated by a sensitivity analysis. The results derived provide general understanding on the economic competitiveness of SOE for sustainable biogas upgrading, thus assisting the decision making for biogas production sites. The research leading to the presented work is funded by European Union’s Horizon 2020 under grant agreements n° 699892 (ECo, topic H2020-JTI-FCH-2015-1) and SCCER BIOSWEET.

Keywords: biogas upgrading, solid-oxide electrolyzer, co-electrolysis, CO₂ utilization, energy storage

Procedia PDF Downloads 148

Authors: Fulya Asena Uluç, Ehsan Tuzcuoğlu, Songül Bayraktar, Burak Koca, Alper Gürarslan

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Microplastics are contaminants that are widely distributed in the environment with a detrimental ecological effect. Besides this, recent research has proved the existence of microplastics in human blood and organs. Microplastics in the environment can be divided into two main categories: primary and secondary microplastics. Primary microplastics are plastics that are released into the environment as microscopic particles. On the other hand, secondary microplastics are the smaller particles that are shed as a result of the consumption of synthetic materials in textile products as well as other products. Textiles are the main source of microplastic contamination in aquatic ecosystems. Laundry of synthetic textiles (34.8%) accounts for an average annual discharge of 3.2 million tons of primary microplastics into the environment. Recently, microfiber shedding from laundry research has gained traction. However, no comprehensive study was conducted from the standpoint of rinsing parameters during laundry to analyze microfiber shedding. The purpose of the present study is to quantify microfiber shedding from fabric under different rinsing conditions and determine the effective rinsing parameters on microfiber release in a laundry environment. In this regard, a parametric study is carried out to investigate the key factors affecting the microfiber release from a front-load washing machine. These parameters are the amount of water used during the rinsing step and the spinning speed at the end of the washing cycle. Minitab statistical program is used to create a design of the experiment (DOE) and analyze the experimental results. Tests are repeated twice and besides the controlled parameters, other washing parameters are kept constant in the washing algorithm. At the end of each cycle, released microfibers are collected via a custom-made filtration system and weighted with precision balance. The results showed that by increasing the water amount during the rinsing step, the amount of microplastic released from the washing machine increased drastically. Also, the parametric study revealed that increasing the spinning speed results in an increase in the microfiber release from textiles.

Keywords: front load, laundry, microfiber, microfiber release, microfiber shedding, microplastic, pollution, rinsing parameters, sustainability, washing parameters, washing machine

Procedia PDF Downloads 90

Authors: Tacho Rubby Kong

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Community health workers’ performances are known to influence members’ behaviours and practices while translating policies into service delivery. However, little remains known about the extent to which this remains true within interventions aimed at addressing malaria burden in low-resource settings like Cameroon. The objective of this study was to examine the health workers’ performance and their influence on the adoption of strategies to address the malaria burden at a subnational level health system in Cameroon. A qualitative exploratory design was adopted on a purposively selected sample of 18 key informants. The study was conducted in Konye health district among sub-national health systems, managers, health facility in-charges, and frontline community health workers. Data was collected using semi-structured interview guides in a face-to-face interview with respondents. The analysis adopted a thematic approach utilising journals, credible authors, and peer review articles for data management. Participants acknowledged that workplace networks were influential during the implementation of policies to address malaria. The influence exerted was in form of linkage with other services, caution, and advice regarding strict adherence to policy recommendations, perhaps reflective of the level of trust in providers’ ability to adhere to policy provisions. At the district health management level and among non-state actors, support in perceived areas of weak performance in policy implementation was observed. In addition, timely initiation of contact and subsequent referral was another aspect where community health workers exerted influence while translating policies to address the malaria burden. While the level of support from among network peers was observed to influence community health workers’ adoption and implementation of strategies to address the malaria burden, different mechanisms triggered subsequent response and level of adherence to recommended policy aspects. Drawing from the elicited responses, it was infer that community health workers’ performance influence the direction and extent of success in policy implementation to address the malaria burden at the subnational level.

Keywords: subnational, community, malaria, strategy

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Authors: Marta Ribo, Ian D. Goodwin, Thomas Mortlock, Phil O’Brien

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Coastal behavior is best investigated using a sediment budget approach, based on the identification of sediment sources and sinks. Grain size distribution over the New South Wales (NSW) continental shelf has been widely characterized since the 1970’s. Coarser sediment has generally accumulated on the outer shelf, and/or nearshore zones, with the latter related to the presence of nearshore reef and bedrocks. The central part of the NSW shelf is characterized by the presence of fine sediments distributed parallel to the coastline. This study presents new grain size distribution maps along the NSW continental shelf, built using all available NSW and Commonwealth Government holdings. All available seabed bathymetric data form prior projects, single and multibeam sonar, and aerial LiDAR surveys were integrated into a single bathymetric surface for the NSW continental shelf. Grain size information was extracted from the sediment sample data collected in more than 30 studies. The information extracted from the sediment collections varied between reports. Thus, given the inconsistency of the grain size data, a common grain size classification was her defined using the phi scale. The new sediment distribution maps produced, together with new detailed seabed bathymetric data enabled us to revise the delineation of sediment compartments to more accurately reflect the true nature of sediment movement on the inner shelf and nearshore. Accordingly, nine primary mega coastal compartments were delineated along the NSW coast and shelf. The sediment compartments are bounded by prominent nearshore headlands and reefs, and major river and estuarine inlets that act as sediment sources and/or sinks. The new sediment grain size distribution was used as an input in the morphological modelling to quantify the sediment transport patterns (and indicative rates of transport), used to investigate sand supply rates and processes from the lower shoreface to the NSW coast. The rate of sand supply to the NSW coast from deep water is a major uncertainty in projecting future coastal response to sea-level rise. Offshore transport of sand is generally expected as beaches respond to rising sea levels but an onshore supply from the lower shoreface has the potential to offset some of the impacts of sea-level rise, such as coastline recession. Sediment exchange between the lower shoreface and sub-aerial beach has been modelled across the south, central, mid-north and far-north coast of NSW. Our model approach is that high-energy storm events are the primary agents of sand transport in deep water, while non-storm conditions are responsible for re-distributing sand within the beach and surf zone.

Keywords: New South Wales coast, off-shore transport, sand supply, sediment distribution maps

Procedia PDF Downloads 223

Authors: Aneia Rajiel Busmente, Renato Gunio Jr., Jazin Mautante, Denise Joy Mendoza, Raymond Benedict Tagorio, Gabriel Uy, Natalie Quinn Valenzuela, Ma. Elayza Villa, Francine Yezha Vizcarra, Sofia Madelle Yapan, Eugene Kurt Yboa

Abstract:

COVID-19’s rapid spread caused a dramatic change in the nation, especially the educational system. The Department of Education was forced to adopt a practical learning platform without neglecting health, a printed modular distance learning. The Philippines' K–12 curriculum includes Statistics and Probability as one of the key courses as it offers students the knowledge to evaluate and comprehend data. Due to student’s difficulty and lack of understanding of the concepts of Statistics and Probability in Normal Distribution. The Self-Learning Module in Statistics and Probability about the Normal Distribution created by the Department of Education has several problems, including many activities, unclear illustrations, and insufficient examples of concepts which enables learners to have a difficulty accomplishing the module. The purpose of this study is to determine the effectiveness of self-learning module on the academic performance of students in the subject Statistics and Probability, it will also explore students’ perception towards the quality of created Self-Learning Module in Statistics and Probability. Despite the availability of Self-Learning Modules in Statistics and Probability in the Philippines, there are still few literatures that discuss its effectiveness in improving the performance of Senior High School students in Statistics and Probability. In this study, a Self-Learning Module on Normal Distribution is evaluated using a quasi-experimental design. STEM students in Grade 11 from National University's Nazareth School will be the study's participants, chosen by purposive sampling. Google Forms will be utilized to find at least 100 STEM students in Grade 11. The research instrument consists of 20-item pre- and post-test to assess participants' knowledge and performance regarding Normal Distribution, and a Likert scale survey to evaluate how the students perceived the self-learning module. Pre-test, post-test, and Likert scale surveys will be utilized to gather data, with Jeffreys' Amazing Statistics Program (JASP) software being used for analysis.

Keywords: self-learning module, academic performance, statistics and probability, normal distribution

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