Search results for: construction risk assessment model

Authors: Peter Egri, Tamas Kis

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Scheduling problems have been studied by the algorithmic mechanism design research from the beginning. This paper is focusing on a practically important, but theoretically rather neglected field: the project scheduling problem where the jobs connected by precedence constraints compete for various nonrenewable resources, such as materials. Although the centralized problem can be solved in polynomial-time by applying the algorithm of Carlier and Rinnooy Kan from the Eighties, obtaining materials in a decentralized environment is usually far from optimal. It can be observed in practical production scheduling situations that project managers tend to cache the required materials as soon as possible in order to avoid later delays due to material shortages. This greedy practice usually leads both to excess stocks for some projects and materials, and simultaneously, to shortages for others. The aim of this study is to develop a model for the material allocation problem of a production plant, where a central decision maker—the inventory—should assign the resources arriving at different points in time to the jobs. Since the actual due dates are not known by the inventory, the mechanism design approach is applied with the projects as the self-interested agents. The goal of the mechanism is to elicit the required information and allocate the available materials such that it minimizes the maximal tardiness among the projects. It is assumed that except the due dates, the inventory is familiar with every other parameters of the problem. A further requirement is that due to practical considerations monetary transfer is not allowed. Therefore a mechanism without money is sought which excludes some widely applied solutions such as the Vickrey–Clarke–Groves scheme. In this work, a type of Serial Dictatorship Mechanism (SDM) is presented for the studied problem, including a polynomial-time algorithm for computing the material allocation. The resulted mechanism is both truthful and Pareto optimal. Thus the randomization over the possible priority orderings of the projects results in a universally truthful and Pareto optimal randomized mechanism. However, it is shown that in contrast to problems like the many-to-many matching market, not every Pareto optimal solution can be generated with an SDM. In addition, no performance guarantee can be given compared to the optimal solution, therefore this approximation characteristic is investigated with experimental study. All in all, the current work studies a practically relevant scheduling problem and presents a novel truthful material allocation mechanism which eliminates the potential benefit of the greedy behavior that negatively influences the outcome. The resulted allocation is also shown to be Pareto optimal, which is the most widely used criteria describing a necessary condition for a reasonable solution.

Keywords: material allocation, mechanism without money, polynomial-time mechanism, project scheduling

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Authors: Drazen Simlesa, Jelena Pudjak, Anita Tonkovic Busljeta

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Regarding social economy (SE), Croatia is, on general level, considered as ex-communist country with good tradition, bad performance in second part of 20th Century because of political control in the business sector, which has in transition period (1990-1999) became a problem of ignorance in public administration (policy level). Today, social economy in Croatia is trying to catch up with other EU states on all important levels of SE sector: legislative and institutional framework, financial infrastructure, education and capacity building, and visibility. All four are integral parts of Strategy for the Development of Social Entrepreneurship in the Republic of Croatia for the period of 2015 – 2020. Within iPRESENT project, funded by Croatian Science Foundation, we have mapped social economy actors and after many years there is a clear and up to date social economy base. At the ICSE 2016 we will present main outcomes and results of this process. In the second year of the project we conducted a field research across Croatia carried out 19 focus groups with most influential, innovative and inspirational social economy actors. We divided interview questions in four themes: laws on social economy and public policies, definition/ideology of social economy and cooperation on SE scene, the level of democracy and working conditions, motivation and existence of intrinsic values. The data that are gathered through focus group interviews has been analysed via qualitative data analysis software (Atlas ti.). Major finding that will be presented in ICSA 2016 are: Social economy actors are mostly unsatisfied with legislative and institutional framework in Croatia and consider it as unsupportive and confusing. Social economy actors consider SE to be in the line with WISE model and as a tool for community development. The SE actors that are more active express satisfaction with cooperation amongst SE actors and other partners and stakeholders, but the ones that are in more isolated conditions (spatially) express need for more cooperation and networking. Social economy actors expressed their praise for democratic atmosphere in their organisations and fair working conditions. And finally, they expressed high motivation to continue to work in the social economy and are dedicated to the concept, including even those that were at the beginning interested just in getting a quick job. It means that we can detect intrinsic values for employees in social economy organisations. This research enabled us to describe for the first time in Croatia the view from the inside, attitudes and opinion of employees of social economy organisations.

Keywords: employees, focus groups, mapping, social economy

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Authors: S. Vivek, Sharad Sharan, R. Arvind, D. V. Praveen, J. Vigneshwar, S. Ajith, V. R. Sanal Kumar

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In this paper numerical studies have been carried out to examine the starting transient flow features of high-performance solid propellant rocket motors with different port geometries but with same propellant loading density. Numerical computations have been carried out using a 3D SST k-ω turbulence model. This code solves standard k-omega turbulence equations with shear flow corrections using a coupled second order implicit unsteady formulation. In the numerical study, a fully implicit finite volume scheme of the compressible, Reynolds-Averaged, Navier-Stokes equations are employed. We have observed from the numerical results that in solid rocket motors with highly loaded propellants having divergent port geometry the hot igniter gases can create pre-ignition thrust oscillations due to flow unsteadiness and recirculation. Under these conditions the convective flux to the surface of the propellant will be enhanced, which will create reattachment point far downstream of the transition region and it will create a situation for secondary ignition and formation of multiple-flame fronts. As a result the effective time required for the complete burning surface area to be ignited comes down drastically giving rise to a high pressurization rate (dp/dt) in the second phase of starting transient. This in effect could lead to starting thrust oscillations and eventually a hard start of the solid rocket motor. We have also observed that the igniter temperature fluctuations will be diminished rapidly and will reach the steady state value faster in the case of solid propellant rocket motors with convergent port than the divergent port irrespective of the igniter total pressure. We have concluded that the thrust oscillations and unexpected thrust spike often observed in solid rockets with non-uniform ports are presumably contributed due to the joint effects of the geometry dependent driving forces, transient burning and the chamber gas dynamics forces. We also concluded that the prudent selection of the port geometry, without altering the propellant loading density, for damping the total temperature fluctuations within the motor is a meaningful objective for the suppression and control of instability and/or pressure/thrust oscillations often observed in solid propellant rocket motors with non-uniform port geometry.

Keywords: ignition transient, solid rockets, starting transient, thrust transient

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Authors: Avent Grange, Frederic Bertrand, Jean-Baptiste Droin, Amandine Marrel, Jean-Henry Ferrasse, Olivier Boutin

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CEA and its industrial partners are designing a gas Power Conversion System (PCS) based on a Brayton cycle for the ASTRID Sodium-cooled Fast Reactor. Investigations of control and regulation requirements to operate this PCS during operating, incidental and accidental transients are necessary to adapt core heat removal. To this aim, we developed a methodology to optimize the thermal-hydraulic behavior of the reactor during normal operations, incidents and accidents. This methodology consists of a multi-objective optimization for a specific sequence, whose aim is to increase component lifetime by reducing simultaneously several thermal stresses and to bring the reactor into a stable state. Furthermore, the multi-objective optimization complies with safety and operating constraints. Operating, incidental and accidental sequences use specific regulations to control the thermal-hydraulic reactor behavior, each of them is defined by a setpoint, a controller and an actuator. In the multi-objective problem, the parameters used to solve the optimization are the setpoints and the settings of the controllers associated with the regulations included in the sequence. In this way, the methodology allows designers to define an optimized and specific control strategy of the plant for the studied sequence and hence to adapt PCS piloting at its best. The multi-objective optimization is performed by evolutionary algorithms coupled to surrogate models built on variables computed by the thermal-hydraulic system code, CATHARE2. The methodology is applied to a loss of off-site power sequence. Three variables are controlled: the sodium outlet temperature of the sodium-gas heat exchanger, turbomachine rotational speed and water flow through the heat sink. These regulations are chosen in order to minimize thermal stresses on the gas-gas heat exchanger, on the sodium-gas heat exchanger and on the vessel. The main results of this work are optimal setpoints for the three regulations. Moreover, Proportional-Integral-Derivative (PID) control setting is considered and efficient actuators used in controls are chosen through sensitivity analysis results. Finally, the optimized regulation system and the reactor control procedure, provided by the optimization process, are verified through a direct CATHARE2 calculation.

Keywords: gas power conversion system, loss of off-site power, multi-objective optimization, regulation, sodium fast reactor, surrogate model

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Authors: Medhat Tawfik, Ezzat Abd El Lateef, Bahr Amany, Mohamed Magda

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Applying organic farming systems in biosaline agriculture is unconventional approach for sustainable use of marginal soil and desert land for planting non-traditional halophytic crops such as Leptochloa fusca, Kochia indica, Sporobolus virginicus and Spartina patens. These plants are highly salt tolerant C4 halophytic forage plants grown well in coastal salt marsh. These halophytic plant will take important place in the farming system, especially in the coastal areas and salt-affected land. We can call it environmentally smart crops because they ensure food security, contribute to energy security, guarantee environmental sustainability, and mitigate the negative impacts of climate change. Organic Agriculture is the most important and widely practiced agro-ecological farming system. It is claimed to be the most sustainable approach and long term adaptation strategy. It promotes soil fertility and diversity at all levels and makes soils less susceptible to erosion. It is also reported to be climate change resilience farming systems as it promotes the proper management of soil, water, biodiversity and local knowledge and provides producers with ecologically sound management decisions. A field experiment was carried out at the Model Farm of National Research Centre, El Tour, South Sinai to study the impact of (Mycorrhiza 1kg/fed., charcoal 4 tons/fed., chicken manure 5 tons/fed., in addition to control treatment) on some growth characters, photosynthetic pigments content, and some physiological aspects i.e. prolind and soluble carbohydrates content, succulence and osmotic pressure values, as well as nutritive values i.e. Crude fat (CF), Acid detergent fiber (ADF), Neutral detergent fiber (NDF), Ether extract (EE) and Nitrogen-free extract (NFE) of five halophytic plant species (Leptochloa fusca, Kochia indica, Sporobolus virginicus and Spartina patens). Our results showed that organic fertilizer treatment enhanced all the previous character as compared with control with superiority to chicken manure over the other treatments.

Keywords: organic agriculture, halophytic plants, saline environment, water security

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Authors: Zarina Chokparova, Ighor Uzhinsky

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Carbon dioxide emissions resulting from burning of the fossil fuels on large scales, such as oil industry or power plants, leads to a plenty of severe implications including global temperature raise, air pollution and other adverse impacts on the environment. Besides some precarious and costly ways for the alleviation of CO₂ emissions detriment in industrial scales (such as liquefaction of CO₂ and its deep-water treatment, application of adsorbents and membranes, which require careful consideration of drawback effects and their mitigation), one physically and commercially available technology for its capture and disposal is supersonic system for inertial extraction of CO₂ in after-combustion streams. Due to the flue gas with a carbon dioxide concentration of 10-15 volume percent being emitted from the combustion system, the waste stream represents a rather diluted condition at low pressure. The supersonic system induces a flue gas mixture stream to expand using a converge-and-diverge operating nozzle; the flow velocity increases to the supersonic ranges resulting in rapid drop of temperature and pressure. Thus, conversion of potential energy into the kinetic power causes a desublimation of CO₂. Solidified carbon dioxide can be sent to the separate vessel for further disposal. The major advantages of the current solution are its economic efficiency, physical stability, and compactness of the system, as well as needlessness of addition any chemical media. However, there are several challenges yet to be regarded to optimize the system: the way for increasing the size of separated CO₂ particles (as they are represented on a micrometers scale of effective diameter), reduction of the concomitant gas separated together with carbon dioxide and provision of CO₂ downstream flow purity. Moreover, determination of thermodynamic conditions of the vapor-solid mixture including specification of the valid and accurate equation of state remains to be an essential goal. Due to high speeds and temperatures reached during the process, the influence of the emitted heat should be considered, and the applicable solution model for the compressible flow need to be determined. In this report, a brief overview of the current technology status will be presented and a program for further evaluation of this approach is going to be proposed.

Keywords: CO₂ sequestration, converging diverging nozzle, fossil fuel power plant emissions, inertial CO₂ extraction, supersonic post-combustion carbon dioxide capture

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Authors: Po-Chien Li

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Despite the extant literature has hosted a wide-range of knowledge about trade shows, this knowledge base deserves to be further expanded and extended because there exist many unclear issues and overlooked topics. One area that needs much research attention is regarding the behavior and performance of booth workers at the exhibition site. Booth staffs play many key roles in interacting with booth visitors. Their exhibiting-related attitudes and motivations might have significant consequences on a firm’s exhibition results. However, to date, little research, if any, has studied how booth workers are affected and behave in the context of trade fair. The primary purpose of the current study is to develop and test a research model, derived from role theory and resource-based viewpoint, that depicts the effects of a firm’s pre-exhibition resource investment behavior on booth staff’s role perceptions and work behavior during the exhibition period. The author collects data with two survey questionnaires at two trade shows in 2016. One questionnaire is given to the booth head of an exhibiting company, asking about the firm’s resource commitment behavior prior to the exhibition period. In contrast, another questionnaire is provided for a booth worker of the same firm, requesting the individual staff to report his/her own role perceptions, degree of exhibition goal acceptance, and level of work effort during the exhibition period. The study has utilized the following analytic methods, including descriptive statistics, exploratory factor analysis, reliability analysis, and regression analysis. The results of a set of regression analyses show that a firm’s pre-exhibition resource investment behavior has significant effects on a booth staff’s exhibiting perceptions and attitudes. Specifically, an exhibitor’s resource investment behavior has impacts on the factors of booth staff’s role clarity and role conflict. In addition, a booth worker’s role clarity is related to the degree of exhibition goal acceptance, but his/her role conflict is not. Finally, a booth worker’s exhibiting effort is significantly related to the individual’s role clarity, role conflict and goal acceptance. In general, the major contribution of the current research is that it offers insight into and early evidence on the links between an exhibiting firm’s resource commitment behavior and the work perceptions and attitudes of booth staffs during the exhibition period. The current research’s results can benefit the extant literature of exhibition marketing.

Keywords: exhibition resource investment, role perceptions, goal acceptance, work effort

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Authors: Yeliz Cakir Kocak, Hafize Ozturk Can, Sibel Icke, Ummahan Yucel, Esin Ceber Turfan

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Introduction: Midwifery organization in Turkey became official in 1954 with the foundation of Midwifery Association. Today there are two Professional organizations representing midwives: ‘Midwifery Association’ and ‘Association for Education, Research and Development in Midwifery (AERDM)’. In recent years, conjuction with the increase in the numbers of midwives, professional consciousness and professional organization conscious is increasing. The undergraduates of Midwifery Department of Ege University İzmir Ataturk School of Health have come together for their professions when they’re stil students, so they founded ‘Midwifery Community of Ege University (MCEU) (EGEBET in Turkish)’ in counseling within structors and the confirmation of the university in 2013. Objective: The aim of this presentation is to reveal the activities and grades of an undergraduate community in-three-years, founded by the undergraduates in order to raise awareness in pregraduate Professional organization. Thus it is aimed to be aware towards postgraduate Professional organization, and to reflect Professional unity and solidarity, alongside personal development to midwifery services by maintaining Professional development. In-the-presentation it is aimed to explain what dimension the organization of midwifery students in Turkey is, and to be a stimulus so that ICM can be more active on undergraduate communities. Findings: MCEU’s an activity that has launched in the scope of Social Responsibility Lecture instructed in curricula of second grade in the Midwifery Department. The community have performed lots activities to reach their objectives between the years of 2013-2016. MCEU have had 65 members in a very-soon period. Today the community that goes on its activities on social network in order to abolish the distances and reach more midwifery students’ve 444 members. MCEU aiming to make all the students of the Midwifery Department a member of this association also accepts the applications of national and international midwifery students. More over the community has published two student periodical magazine and carries out activities on Midwifery Day each year. Conclusion: In conjuction with the national introduction of MCEU in the student congress in 2013, it has received consultancy from the members of MCEU as a sample model in the student organization of midwifery department of other universities in Turkey, and stil remains receiving. Furthermore a student community has been founded under the roof of association with the demand of community’s members. Also academician has a responsibility to give direction to the future and shape the future. Therefore, it is thought that the study can be an instance for all branches of science students and academics. Acknowledgment: We thank to founder members of MCEU and all the other students remaining to perform activities because of their contributions to Professional organization.

Keywords: current situation, midwifery, organization, student

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Authors: Zbigniew Czyz, Krzysztof Skiba, Miroslaw Wendeker

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This paper discusses the results of aerodynamic investigation of the Tajfun gyroplane body designed by a Polish company, Aviation Artur Trendak. This gyroplane has been studied as a 1:8 scale model. Scaling objects for aerodynamic investigation is an inherent procedure in any kind of designing. If scaling, the criteria of similarity need to be satisfied. The basic criteria of similarity are geometric, kinematic and dynamic. Despite the results of aerodynamic research are often reduced to aerodynamic coefficients, one should pay attention to how values of coefficients behave if certain criteria are to be satisfied. To satisfy the dynamic criterion, for example, the Reynolds number should be focused on. This is the correlation of inertial to viscous forces. With the multiplied flow speed by the specific dimension as a numerator (with a constant kinematic viscosity coefficient), flow speed in a wind tunnel research should be increased as many times as an object is decreased. The aerodynamic coefficients specified in this research depend on the real forces that act on an object, its specific dimension, medium speed and variations in its density. Rapid prototyping with a 3D printer was applied to create the research object. The research was performed with a T-1 low-speed wind tunnel (its diameter of the measurement volume is 1.5 m) and a six-element aerodynamic internal scales, WDP1, at the Institute of Aviation in Warsaw. This T-1 wind tunnel is low-speed continuous operation with open space measurement. The research covered a number of the selected speeds of undisturbed flow, i.e. V = 20, 30 and 40 m/s, corresponding to the Reynolds numbers (as referred to 1 m) Re = 1.31∙106, 1.96∙106, 2.62∙106 for the angles of attack ranging -15° ≤ α ≤ 20°. Our research resulted in basic aerodynamic characteristics and observing the impact of undisturbed flow speed on the correlation of aerodynamic coefficients as a function of the angle of attack of the gyroplane body. If the speed of undisturbed flow in the wind tunnel changes, the aerodynamic coefficients are significantly impacted. At speed from 20 m/s to 30 m/s, drag coefficient, Cx, changes by 2.4% up to 9.9%, whereas lift coefficient, Cz, changes by -25.5% up to 15.7% if the angle of attack of 0° excluded or by -25.5% up to 236.9% if the angle of attack of 0° included. Within the same speed range, the coefficient of a pitching moment, Cmy, changes by -21.1% up to 7.3% if the angles of attack -15° and -10° excluded or by -142.8% up to 618.4% if the angle of attack -15° and -10° included. These discrepancies in the coefficients of aerodynamic forces definitely need to consider while designing the aircraft. For example, if load of certain aircraft surfaces is calculated, additional correction factors definitely need to be applied. This study allows us to estimate the discrepancies in the aerodynamic forces while scaling the aircraft. This work has been financed by the Polish Ministry of Science and Higher Education.

Keywords: aerodynamics, criteria of similarity, gyroplane, research tunnel

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Authors: Alia Aldarmaki, Ahmad Elshennawy

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There is a global shift in healthcare systems’ emphasizing engaging different stakeholders in selecting quality improvement initiatives and incorporating their preferences to improve the healthcare efficiency and outcomes. Although experts bring scientific knowledge based on the scientific model and their personal experience, other stakeholders can bring new insights and information into the decision-making process. This study attempts to explore the impact of incorporating different stakeholders’ preference in identifying the most significant criteria that should be considered in healthcare for electing the improvement projects. A Framework based on a modified Fuzzy Delphi Method (FDM) was built. In addition to, the subject matter experts, doctors/physicians, nurses, administrators, and managers groups contribute to the selection process. The research identifies potential criteria for evaluating projects in healthcare, then utilizes FDM to capture expertise knowledge. The first round in FDM is intended to validate the identified list of criteria from experts; which includes collecting additional criteria from experts that the literature might have overlooked. When an acceptable level of consensus has been reached, a second round is conducted to obtain experts’ and other related stakeholders’ opinions on the appropriate weight of each criterion’s importance using linguistic variables. FDM analyses eliminate or retain the criteria to produce a final list of the critical criteria to select improvement projects in healthcare. Finally, reliability and validity were investigated using Cronbach’s alpha and factor analysis, respectively. Two case studies were carried out in a public hospital in the United Arab Emirates to test the framework. Both cases demonstrate that even though there were common criteria between the experts and the stakeholders, still stakeholders’ perceptions bring additional critical criteria into the evaluation process, which can impact the outcomes. Experts selected criteria related to strategical and managerial aspects, while the other participants preferred criteria related to social aspects such as health and safety and patients’ satisfaction. The health and safety criterion had the highest important weight in both cases. The analysis showed that Cronbach’s alpha value is 0.977 and all criteria have factor loading greater than 0.3. In conclusion, the inclusion of stakeholders’ perspectives is intended to enhance stakeholders’ engagement, improve transparency throughout the decision process, and take robust decisions.

Keywords: Fuzzy Delphi Method, fuzzy number, healthcare, stakeholders

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Authors: Ana M. Lara, Manuela Llano, Felipe Gaitán, Rosa H. Bustos, Ana Maria Perdomo-Arciniegas, Ximena Bonilla

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Umbilical cord blood is used as a source of progenitor and stem cells for the regeneration of the hematopoietic and immune system to treat patients with different hematological or non-hematological diseases. This stem cell source represents an advantage over the use of bone marrow or mobilized peripheral blood because it has a lower incidence rate of graft-versus-host disease, probably due to fewer immunological compatibility restrictions. However, its low cellular dose limits its use in pediatric patients. This work proposes the standardization of a cell expansion technique to compensate for the dose of infused cells through the ex-vivo manipulation of hematopoietic progenitor cells from umbilical cord blood before transplantation. The expansion model is carried out through co-cultures with mesenchymal stem cells (MSC) from bone marrow (BM) and less explored fetal tissues such as Wharton's jelly (WJ) and umbilical cord blood (UCB). Initially, a master cell bank of primary mesenchymal stem cells isolated from different sources was established and characterized following International Society of Cell Therapies (ISCT) indications. Additionally, we assessed the effect of a short 25 Gy cycle of gamma irradiation on cell cycle arrest of mesenchymal cells over the support capacity for the expansion of hematopoietic stem cells from umbilical cord blood was evaluated. The results show that co-cultures with MSC from WJ and UCB allow the cellular dose of HSPC to be maximized between 5 and 16 times having a similar support capacity as BM. In addition, was evaluated the hematopoietic stem progenitor cell's HSPC functionality through the evaluation of migration capacity, their differentiation capacity during culture time by flow cytometry to evaluate the expression of membrane markers associated with lineage-committed progenitors, their clonogenic potential, and the evaluation of secretome profile in the expansion process was evaluated. So far, the treatment with gamma irradiation maintains the hematopoietic support capacity of mesenchymal stem cells from the three sources studied compared to treatments without irradiation, favoring the use of fetal tissues that are generally waste to obtain mesenchymal cell lines for ex-vivo expansion systems. With the results obtained, a standardized protocol that will contribute to the development of ex-vivo expansion with MSC on a larger scale will be achieved, enabling its clinical use and expanding its application in adults.

Keywords: ex-vivo expansion, hematopoietic stem cells, hematopoietic stem cell transplantation, mesenchymal stem cells, umbilical cord blood

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Authors: R. O. Babatunde, O. M. Igbalajobi, F. Matambalya

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Moderate economic growth in developing and emerging countries has led to improvement in the food consumption and nutrition situation in the last two decades. Nevertheless, about 870 million people, with a quarter of them from Sub-Saharan Africa, are still suffering from hunger worldwide. As part of measures to reduce the widespread poverty and hunger, cash transfer programmes are now being implemented in many countries of the world. While nationwide cash transfer schemes are few in Sub-Saharan Africa generally, the available ones are more concentrated in East and Southern Africa. Much of the available literature on social protection had focused on the poverty impact of cash transfer schemes at the household level, with the larger proportion originating from Latin America. On the contrary, much less empirical studies have been conducted on the poverty impact of cash transfer in Sub-Saharan Africa, let alone on the food security and nutrition impact. To fill this gap in knowledge, this paper examines the impact of cash transfer on food security in Nigeria. As a case study, the paper analysed the Ekiti State Cash Transfer Scheme (ECTS). ECTS is an unconditional transfer scheme which was established in 2011 to directly provide cash transfer to elderly persons aged 65 years and above in Ekiti State of Nigeria. Using survey data collected in 2013, we analysed the impact of the scheme on food availability and dietary diversity of the beneficiary households. Descriptive and Propensity Score Matching (PSM) techniques were used to estimate the Average Treatment Effect (ATE) and Average Treatment Effect on the Treated (ATT) among the beneficiary and control groups. Thereafter, a model to test for the impact of participation in the cash transfer scheme on calorie availability and dietary diversity was estimated. The results indicate that while households in the sample are clearly vulnerable, there were statistically significant differences between the beneficiary and control groups. For instance, monthly expenditure, calorie availability and dietary diversity were significantly larger among the beneficiary and consequently, the prevalence and depth of hunger were lower in the group. Econometric results indicate that the cash transfer has a positive and significant effect on food availability and dietary diversity in the households. Expanding the coverage of the present scheme to cover all eligible households in the country and incorporating cash transfer into a comprehensive hunger reduction policy will make it to have a greater impact at improving food security among the most vulnerable households in the country.

Keywords: calorie availability, cash transfers, dietary diversity, propensity score matching

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Authors: Kamal Kithsiri Karunadasa Hewawasam Revulge

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This paper is an interpretative historical analysis of Australian migration laws that examines asylum and refugee policies and attitudes in Australia. It looks at major turning points in Australian migration history, and in doing so, the researcher reviewed relevant literature on the aspects crucial to highlighting the current trend of Australian migration policies. The data was collected using secondary data from official government sources, including annual reports, media releases on immigration, inquiry reports, statistical information, and other available literature to identify critical historical events that significantly affected the systematic developments of asylum seekers and refugee policies in Australia and to look at the historical trends of official thinking. A reliance on using these official sources is justified as those are the most convincing sources to analyse the historical events in Australia. Additional literature provides us with critical analyses of the behaviour and culture of the Australian immigration administration. The analytical framework reviewed key Australian Government immigration policies since British colonization and the settlement era of 1787–the 1850s and to the present. The fundamental basis for doing so is that past events and incidents offer us clues and lessons relevant to the present day. Therefore, providing a perspective on migration history in Australia helps analyse how current policymakers' strategies developed and changed over time. Attention is also explicitly focused on Australian asylum and refugee policy internationally, as it helped to broaden the analysis. The finding proved a link between past events and adverse current Australian government policies towards asylum seekers and refugees. It highlighted that Australia's current migration policies are part of a carefully and deliberately planned pattern that arose from the occupation of Australia by early British settlers. In this context, the remarkable point is that the historical events of taking away children from their Australian indigenous parents, widely known as the 'stolen generation' reflected a model of assimilation, or a desire to absorb other cultures into Australian society by fully adopting the settlers' language, their culture, and losing indigenous people's traditions. Current Australian policies towards migrants reflect the same attitude. Hence, it could be argued that policies and attitudes towards asylum seekers and refugees, particularly so-called 'boat people' to some extent, still reflect Australia's earlier colonial and 'white Australia' history.

Keywords: migration law, refugee law, international law, administrative law

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Authors: Chukwuka Justus Iwegbu

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Background: A major concern facing the world is providing senior citizens, individuals with disabilities, and other vulnerable groups with high-quality care. This issue is more serious in Nigeria's North Eastern area, where the burden of disease and disability is heavy, and access to care is constrained. This study aims to fill this gap by exploring the roles, challenges and support needs of caregivers, care home management, funding and administration in challenged communities in North Eastern Nigeria. The study will also provide a comprehensive understanding of the current situation and identify opportunities for improving the quality of care and support for caregivers and care recipients in these communities. Methods: A mixed-methods design, including both quantitative and qualitative data collection methods, will be used, and it will be guided by the stress process model of caregiving. The qualitative stage approach will comprise a survey, In-depth interviews, observations, and focus group discussion and the quantitative analysis will be used in order to comprehend the variations between caregiver's roles and care home management. A review of relevant documents, such as care home policies and funding reports, would be used to gather quantitative data on the administrative and financial aspects of care. The data collected will be analyzed using both descriptive statistics and thematic analysis. A sample size of around 200-300 participants, including caregivers, care recipients, care home managers and administrators, policymakers and health care providers, would be recruited. Findings: The study revealed that caregivers in challenged communities in North Eastern Nigeria face significant challenges, including lack of training and support, limited access to funding and resources, and high levels of burnout. Care home management and administration were also found to be inadequate, with a lack of clear policies and procedures and limited oversight and accountability. Conclusion: There is a need for increased investment in training and support for caregivers, as well as a need for improved care home management and administration in challenged communities in North Eastern Nigeria. It also highlights the importance of involving community members in decision-making and planning processes related to care homes and services. The study would contribute to the existing body of knowledge by providing a detailed understanding of the challenges faced by caregivers, care home managers and administrators.

Keywords: caregivers, care home management, funding, administration, challenge communities, North Eastern Nigeria

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Authors: Berker Bayazit, Gulgun Kayakutlu

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The World Energy Outlook shows that energy markets will substantially change within a few forthcoming decades. First, determined action plans according to COP21 and aim of CO₂ emission reduction have already impact on policies of countries. Secondly, swiftly changed technological developments in the field of renewable energy will be influential upon medium and long-term energy generation and consumption behaviors of countries. Furthermore, share of electricity on global energy consumption is to be expected as high as 40 percent in 2040. Electrical vehicles, heat pumps, new electronical devices and digital improvements will be outstanding technologies and innovations will be the testimony of the market modifications. In order to meet highly increasing electricity demand caused by technologies, countries have to make new investments in the field of electricity production, transmission and distribution. Specifically, electricity generation mix becomes vital for both prevention of CO₂ emission and reduction of power prices. Majority of the research and development investments are made in the field of electricity generation. Hence, the prime source diversity and source planning of electricity generation are crucial for improving the wealth of citizen life. Approaches considering the CO₂ emission and total cost of generation, are necessary but not sufficient to evaluate and construct the product mix. On the other hand, employment and positive contribution to macroeconomic values are important factors that have to be taken into consideration. This study aims to constitute new investments in renewable energies (solar, wind, geothermal, biogas and hydropower) between 2018-2023 under 4 different goals. Therefore, a multi-objective programming model is proposed to optimize the goals of minimizing the CO₂ emission, investment amount and electricity sales price while maximizing the total employment and positive contribution to current deficit. In order to avoid the user preference among the goals, Dinkelbach’s algorithm and Guzel’s approach have been combined. The achievements are discussed with comparison to the current policies. Our study shows that new policies like huge capacity allotment might be discussible although obligation for local production is positive. The improvements in grid infrastructure and re-design support for the biogas and geothermal can be recommended.

Keywords: energy generation policies, multi-objective linear programming, portfolio planning, renewable energy

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Authors: Ergham Al Bachir

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This study adopts strategic leadership (Upper Echelons) as the core theory and contextual leadership theory as the research lens. This research asks how the external context impacts strategic leadership effectiveness to achieve the outcomes in pluralistic organizations (PO). The study explores how the context influences the selection of CEOs, top management teams (TMT), and their leadership effectiveness. POs are characterized by the multiple objectives of their top management teams, divergent objectives, multiple strategies, and multiple governing authorities. The research question is explored by means of a qualitative multiple-case study focusing on healthcare, real estate, and financial services organizations. The data sources are semi-structured interviews, documents, and direct observations. The data analysis strategy is inductive and deploys thematic analysis and cross-case synthesis. The findings differentiate between national and international CEOs' delegation of authority and relationship with the Board of Directors. The findings identify the elements of the dynamic context that influence TMT and PO outcomes. The emergent hybrid strategic and contextual leadership framework shows how the different contextual factors influence strategic direction, PO context, selection of CEOs and TMT, and the outcomes in four pluralistic organizations. The study offers seven theoretical contributions to Upper Echelons, strategic leadership, and contextual leadership research. (1) The integration of two theories revealed how CEO’s impact on the organization is complementary to the contextual impact. (2) Conducting this study in the Middle East contributes to strategic leadership and contextual leadership research. (3) The demonstration of the significant contextual effects on the selection of CEOs. (4 and 5) Two contributions revealed new links between the context, the Board role, internal versus external CEOs, and national versus international CEOs. (6 and 7) This study offered two definitions: what accounts for CEO leadership effectiveness and organizational outcomes. Two methodological contributions were also identified: (1) Previous strategic leadership and Upper Echelons research are mainly quantitative, while this study adopts qualitative multiple-case research with face-to-face interviews. (2) The extrication of the CEO from the TMT advanced the data analysis in strategic leadership research. Four contributions are offered to practice: (1) The CEO's leadership effectiveness inside and outside the organization. (2) Rapid turnover of predecessor CEOs signifies the need for a strategic and contextual approach to CEOs' succession. (3) TMT composition and education impact on TMT-CEO and TMT-TMT interface. (4) Multilevel strategic contextual leadership development framework.

Keywords: strategic leadership, contextual leadership, upper echelons, pluralistic organizations, cross-cultural leadership

Procedia PDF Downloads 92

Authors: Riofrio Jonathan, Fernandez Guillermo

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Renewable energy represented around 80% of the energy matrix for power generation in Ecuador during 2020, so the deployment of current public policies is focused on taking advantage of the high presence of renewable sources to carry out several electrification projects. These projects are part of the portfolio sent to the United Nations Framework on Climate Change (UNFCCC) as a commitment to reduce greenhouse gas emissions (GHG) in the established national determined contribution (NDC). In this sense, the Ecuadorian Organic Energy Efficiency Law (LOEE) published in 2019 promotes E-mobility as one of the main milestones. In fact, it states that the new vehicles for urban and interurban usage must be E-buses since 2025. As a result, and for a successful implementation of this technological change in a national context, it is important to deploy land surveys focused on technical and geographical areas to keep the quality of services in both the electricity and transport sectors. Therefore, this research presents a technological and energy comparison between a conventional diesel bus and its equivalent E-bus. Both vehicles fulfill all the technical requirements to ride in the study-case city, which is Ambato in the province of Tungurahua-Ecuador. In addition, the analysis includes the development of a model for the energy estimation of both technologies that are especially applied in a highland city such as Ambato. The altimetry of the most important bus routes in the city varies from 2557 to 3200 m.a.s.l., respectively, for the lowest and highest points. These operation conditions provide a grade of novelty to this paper. Complementary, the technical specifications of diesel buses are defined following the common features of buses registered in Ambato. On the other hand, the specifications for E-buses come from the most common units introduced in Latin America because there is not enough evidence in similar cities at the moment. The achieved results will be good input data for decision-makers since electric demand forecast, energy savings, costs, and greenhouse gases emissions are computed. Indeed, GHG is important because it allows reporting the transparency framework that it is part of the Paris Agreement. Finally, the presented results correspond to stage I of the called project “Analysis and Prospective of Electromobility in Ecuador and Energy Mix towards 2030” supported by Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ).

Keywords: high altitude cities, energy planning, NDC, e-buses, e-mobility

Procedia PDF Downloads 151

Authors: Elif Gencturk, Ekin Yurdakul, Ahmet Y. Celik, Senol Mutlu, Kutlu O. Ulgen

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Yeast cells are generally used as a model system of eukaryotes due to their complex genetic structure, rapid growth ability in optimum conditions, easy replication and well-defined genetic system properties. Thus, yeast cells increased the knowledge of the principal pathways in humans. During fermentation, carbohydrates (hexoses and pentoses) degrade into some toxic by-products such as 5-hydroxymethylfurfural (5-HMF or HMF) and furfural. HMF influences the ethanol yield, and ethanol productivity; it interferes with microbial growth and is considered as a potent inhibitor of bioethanol production. In this study, yeast single cell behavior under HMF application was monitored by using a continuous flow single phase microfluidic platform. Microfluidic device in operation is fabricated by hot embossing and thermo-compression techniques from cyclo-olefin polymer (COP). COP is biocompatible, transparent and rigid material and it is suitable for observing fluorescence of cells considering its low auto-fluorescence characteristic. The response of yeast cells was recorded through Red Fluorescent Protein (RFP) tagged Nop56 gene product, which is an essential evolutionary-conserved nucleolar protein, and also a member of the box C/D snoRNP complexes. With the application of HMF, yeast cell proliferation continued but HMF slowed down the cell growth, and after HMF treatment the cell proliferation stopped. By the addition of fresh nutrient medium, the yeast cells recovered after 6 hours of HMF exposure. Thus, HMF application suppresses normal functioning of cell cycle but it does not cause cells to die. The monitoring of Nop56 expression phases of the individual cells shed light on the protein and ribosome synthesis cycles along with their link to growth. Further computational study revealed that the mechanisms underlying the inhibitory or inductive effects of HMF on growth are enriched in functional categories of protein degradation, protein processing, DNA repair and multidrug resistance. The present microfluidic device can successfully be used for studying the effects of inhibitory agents on growth by single cell tracking, thus capturing cell to cell variations. By metabolic engineering techniques, engineered strains can be developed, and the metabolic network of the microorganism can thus be manipulated such that chemical overproduction of target metabolite is achieved along with the maximum growth/biomass yield.  

Keywords: COP, HMF, ribosome biogenesis, thermoplastic microbioreactor, yeast

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Authors: Silvia Lucciarini, Antonio Corasaniti

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The issue of democracy in capitalist countries has once again become the focus of debate in recent years. A number of socio-economic and political tensions have triggered discussion of this topic from various perspectives and disciplines. Political developments, the rise of both right-wing parties and populism and the constant growth of inequalities in a context of welfare downsizing, have led scholars to question if European capitalist countries are really capable of creating and redistributing resources and look for elements that might make democratic capital in European countries more dense. The aim of the work is to shed light on the trajectories, intensity and convergence or divergence between political and associative participation, on one hand, and organization, on the other, as these constitute two of the main points of connection between the norms, values and actions that bind citizens to the state. Using the European Social Survey database, some studies have sought to analyse degrees of unionization by investigating the relationship between systems of industrial relations and vulnerable groups (in terms of value-oriented practices or political participation). This paper instead aims to investigate the relationship between union participation and civil/political participation, comparing union members and non-members and then distinguishing between employees and self-employed professionals to better understand participatory behaviors among different workers. The first component of the research will employ a multilinear logistic model to examine a sample of 10 countries selected according to a grid that combines the industrial relations models identified by Visser (2006) and the Welfare State systems identified by Esping-Andersen (1990). On the basis of this sample, we propose to compare the choices made by workers and their propensity to join trade unions, together with their level of social and political participation, from 2002 to 2016. In the second component, we aim to verify whether workers within the same system of industrial relations and welfare show a similar propensity to engage in civil participation through political bodies and associations, or if instead these tendencies take on more specific and varied forms. The results will allow us to see: (1) if political participation is higher among unionized workers than it is among the non-unionized. (2) what are the differences in unionisation and civil/political participation between self-employed, temporary and full-time employees and (3) whether the trajectories within industrial relations and welfare models display greater inclusiveness and participation, thereby confirming or disproving the patterns that have been documented among the different European countries.

Keywords: union membership, participation, democracy, industrial relations, welfare systems

Procedia PDF Downloads 142

Authors: Amin Akbari, Dongcai Wang, Huiru Li, Xiaoping Du, Jie Chen

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The effect of vibrational force (VF) on accelerating orthodontic tooth movement depends on the level of delivered stimulation to the tooth in terms of peak load (PL), which requires contacts between the tooth and the VF device. A personalized device ensures the contacts, but the resulting PL distribution on the teeth is unknown. Furthermore, it is unclear whether the PL on particular teeth can be adjusted to the prescribed values. The objective of this study was to investigate the efficacy of apersonalized VF device in controlling the level of stimulation on two teeth, the mandibular canines and 2nd molars. A 3-D finite element (FE) model of human dentition, including teeth, PDL, and alveolar bone, was created from the cone beam computed tomography images of an anonymous subject. The VF was applied to the teeth through a VFdevice consisting of a mouthpiece with engraved tooth profile of the subject and a VF source that applied 0.3 N force with the frequency of 30 Hz. The dentition and mouthpiece were meshed using 10-node tetrahedral elements. Interface elements were created at the interfaces between the teeth and the mouthpiece. The upper and lower teeth bite on the mouthpiece to receive the vibration. The depth of engraved individual tooth profile could be adjusted, which was accomplished by adding a layer of material as an interference or removing a layer of material as a clearance to change the PL on the tooth. The interference increases the PL while the clearance decreases it. Fivemouthpiece design cases were simulated, which included a mouthpiece without interference/clearance; the mouthpieces with bilateral interferences on both mandibular canines and 2nd molars with magnitudes of 0.1, 0.15, and 0.2-mm, respectively; and mouthpiece with bilateral 0.3-mm clearances on the four teeth. Then, the force distributions on the entire dentition were compared corresponding to these adjustments. The PL distribution on the teeth is uneven when there is no interference or clearance. Among all teeth, the anterior segment receives the highest level of PL. Adding 0.1, 0.15, and 0.2-mm interferences to the canines and 2nd molars bilaterally leads to increase of the PL on the canines by 10, 62, and 73 percent and on the 2nd molar by 14, 55, and 87 percent, respectively. Adding clearances to the canines and 2nd molars by removing the contactsbetween these teeth and the mouthpiece results in zero PL on them. Moreover, introducing interference to mandibular canines and 2nd molarsredistributes the PL on the entireteeth. The share of the PL on the anterior teeth are reduced. The use of the personalized mouthpiece ensures contactsof the teeth to the mouthpiece so that all teeth can be stimulated. However, the PL distribution is uneven. Adding interference between a tooth and the mouthpiece increases the PL while introducing clearance decreases the PL. As a result, the PL is redistributed. This study confirms that the level of VF stimulation on the individual tooth can be adjusted to a prescribed value.

Keywords: finite element method, orthodontic treatment, stress analysis, tooth movement, vibrational force

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Authors: Maria Antonietta Marongiu

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Propositional information in discourse is made coherent, intelligible, and persuasive through metadiscourse. The linguistic and rhetorical choices that writers/speakers make to organize and negotiate content matter are intended to help relate a text to its context. Besides, they help the audience to connect to and interpret a text according to the values of a specific discourse community. Based on these assumptions, this work aims to analyse the use of metadiscourse in the spoken performance of teachers in online EFL, ESP, and subject-teacher courses taught in English to non-native learners in higher education. In point of fact, the global spread of Covid 19 has forced universities to transition their in-class courses to online delivery. This has inevitably placed on the instructor a heavier interactional responsibility compared to in-class courses. Accordingly, online delivery needs greater structuring as regards establishing the reader/listener’s resources for text understanding and negotiating. Indeed, in online as well as in in-class courses, lessons are social acts which take place in contexts where interlocutors, as members of a community, affect the ways ideas are presented and understood. Following Hyland’s Interactional Model of Metadiscourse (2005), this study intends to investigate Teacher Talk in online academic courses during the Covid 19 lock-down in Italy. The selected corpus includes the transcripts of online EFL and ESP courses and subject-teachers online courses taught in English. The objective of the investigation is, firstly, to ascertain the presence of metadiscourse in the form of interactive devices (to guide the listener through the text) and interactional features (to involve the listener in the subject). Previous research on metadiscourse in academic discourse, in college students' presentations in EAP (English for Academic Purposes) lessons, as well as in online teaching methodology courses and MOOC (Massive Open Online Courses) has shown that instructors use a vast array of metadiscoursal features intended to express the speakers’ intentions and standing with respect to discourse. Besides, they tend to use directions to orient their listeners and logical connectors referring to the structure of the text. Accordingly, the purpose of the investigation is also to find out whether metadiscourse is used as a rhetorical strategy by instructors to control, evaluate and negotiate the impact of the ongoing talk, and eventually to signal their attitudes towards the content and the audience. Thus, the use of metadiscourse can contribute to the informative and persuasive impact of discourse, and to the effectiveness of online communication, especially in learning contexts.

Keywords: discourse analysis, metadiscourse, online EFL and ESP teaching, rhetoric

Procedia PDF Downloads 129

Authors: Yali Liu, Maria Avello Iturriagagoitia

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Background: Fitness applications (apps) are one of the most popular mobile health (mHealth) apps. These apps can help prevent/control health issues such as obesity, which is one of the most serious public health challenges in the developed world in recent decades. Compared with the traditional intervention like face-to-face treatment, it is cheaper and more convenient to use fitness apps to interfere with physical activities and healthy behaviors. Nevertheless, fitness applications apps tend to have high abandonment rates and low levels of user engagement. Therefore, maintaining the endurance of users' usage is challenging. In fact, previous research shows a variety of strategies -goal-setting, self-monitoring, coaching, etc.- for promoting fitness and health behavior change. These strategies can influence the users’ perseverance and self-monitoring of the program as well as favoring their adherence to routines that involve a long-term behavioral change. However, commercial fitness apps rarely incorporate these strategies into their design, thus leading to a lack of engagement with the apps. Most of today’s mobile services and brands engage their users proactively via push notifications. Push notifications. These notifications are visual or auditory alerts to inform mobile users about a wide range of topics that entails an effective and personal mean of communication between the app and the user. One of the research purposes of this article is to implement the application of behavior change strategies through push notifications. Proposes: This study aims to better understand the influence that effective use of push notifications combined with the behavioral change strategies will have on users’ engagement with the fitness app. And the secondary objectives are 1) to discuss the sociodemographic differences in utilization of push notifications of fitness apps; 2) to determine the impact of each strategy in customer engagement. Methods: The study uses a combination of the Consumer Engagement Theory and UTAUT2 based model to conduct an online survey among current users of fitness apps. The questionnaire assessed attitudes to each behavioral change strategy, and sociodemographic variables. Findings: Results show the positive effect of push notifications in the generation of consumer engagement and the different impacts of each strategy among different groups of population in customer engagement. Conclusions: Fitness apps with behavior change strategies have a positive impact on increasing users’ usage time and customer engagement. Theoretical experts can participate in designing fitness applications, along with technical designers.

Keywords: behavioral change, customer engagement, fitness app, push notification, UTAUT2

Procedia PDF Downloads 135

Authors: Huayuan Lu, Chunfang Yang, Ma Zhu, Baojun Qi, Yaqiong Qiao, Jiangqian Xu

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Image geolocalization has great application prospects in fields such as autonomous driving and virtual/augmented reality. In practical application scenarios, the size of the image to be located is not fixed; it is impractical to train different networks for all possible sizes. When its size does not match the size of the input of the descriptor extraction model, existing image geolocalization methods usually directly scale or crop the image in some common ways. This will result in the loss of some information important to the geolocalization task, thus affecting the performance of the image geolocalization method. For example, excessive down-sampling can lead to blurred building contour, and inappropriate cropping can lead to the loss of key semantic elements, resulting in incorrect geolocation results. To address this problem, this paper designs a learnable image resizer and proposes an arbitrary-sized image geolocation method. (1) The designed learnable image resizer employs the self-attention mechanism to enhance the geometric features of the resized image. Firstly, it applies bilinear interpolation to the input image and its feature maps to obtain the initial resized image and the resized feature maps. Then, SKNet (selective kernel net) is used to approximate the best receptive field, thus keeping the geometric shapes as the original image. And SENet (squeeze and extraction net) is used to automatically select the feature maps with strong contour information, enhancing the geometric features. Finally, the enhanced geometric features are fused with the initial resized image, to obtain the final resized images. (2) The proposed image geolocalization method embeds the above image resizer as a fronting layer of the descriptor extraction network. It not only enables the network to be compatible with arbitrary-sized input images but also enhances the geometric features that are crucial to the image geolocalization task. Moreover, the triplet attention mechanism is added after the first convolutional layer of the backbone network to optimize the utilization of geometric elements extracted by the first convolutional layer. Finally, the local features extracted by the backbone network are aggregated to form image descriptors for image geolocalization. The proposed method was evaluated on several mainstream datasets, such as Pittsburgh30K, Tokyo24/7, and Places365. The results show that the proposed method has excellent size compatibility and compares favorably to recently mainstream geolocalization methods.

Keywords: image geolocalization, self-attention mechanism, image resizer, geometric feature

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Authors: M. Tarik Boyraz, M. Bilge Imer

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Conventionally cast nickel-based super alloys, such as commercial alloy IN 738 LC, are widely used in manufacturing of industrial gas turbine blades. With carefully designed microstructure and the existence of alloying elements, the blades show improved mechanical properties at high operating temperatures and corrosive environment. The aim of this work is to model and estimate these mechanical properties of IN 738 LC alloy solely based on simulations for projected heat treatment conditions or service conditions. The microstructure (size, fraction and frequency of gamma prime- γ′ and carbide phases in gamma- γ matrix, and grain size) of IN 738 LC needs to be optimized to improve the high temperature mechanical properties by heat treatment process. This process can be performed at different soaking temperature, time and cooling rates. In this work, micro-structural evolution studies were performed experimentally at various heat treatment process conditions, and these findings were used as input for further simulation studies. The operation time, soaking temperature and cooling rate provided by experimental heat treatment procedures were used as micro-structural simulation input. The results of this simulation were compared with the size, fraction and frequency of γ′ and carbide phases, and grain size provided by SEM (EDS module and mapping), EPMA (WDS module) and optical microscope for before and after heat treatment. After iterative comparison of experimental findings and simulations, an offset was determined to fit the real time and theoretical findings. Thereby, it was possible to estimate the final micro-structure without any necessity to carry out the heat treatment experiment. The output of this microstructure simulation based on heat treatment was used as input to estimate yield stress and creep properties. Yield stress was calculated mainly as a function of precipitation, solid solution and grain boundary strengthening contributors in microstructure. Creep rate was calculated as a function of stress, temperature and microstructural factors such as dislocation density, precipitate size, inter-particle spacing of precipitates. The estimated yield stress values were compared with the corresponding experimental hardness and tensile test values. The ability to determine best heat treatment conditions that achieve the desired microstructural and mechanical properties were developed for IN 738 LC based completely on simulations.

Keywords: heat treatment, IN738LC, simulations, super-alloys

Procedia PDF Downloads 248

Authors: Cleyton S. Stampa

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This paper addresses the perspectives of using low melting point metals (LMPMs) as phase change materials (PCMs) in latent thermal energy storage (LTES) units, through a numerical approach. This is a new class of PCMs that has been one of the most prospective alternatives to be considered in LTES, due to these materials present high thermal conductivity and elevated heat of fusion, per unit volume. The chosen type of LTES consists of several horizontal parallel slabs filled with PCM. The heat transfer fluid (HTF) circulates through the channel formed between each two consecutive slabs on a laminar regime through forced convection. The study deals with the LTES charging process (heat-storing) by using pure gallium as PCM, and it considers heat conduction in the solid phase during melting driven by natural convection in the melt. The transient heat transfer problem is analyzed in one arbitrary slab under the influence of the HTF. The mathematical model to simulate the isothermal phase change is based on a volume-averaged enthalpy method, which is successfully verified by comparing its predictions with experimental data from works available in the pertinent literature. Regarding the convective heat transfer problem in the HTF, it is assumed that the flow is thermally developing, whereas the velocity profile is already fully developed. The study aims to learn about the effect of the solid subcooling in the melting rate through comparisons with the melting process of the solid in which it starts to melt from its fusion temperature. In order to best understand this effect in a metallic compound, as it is the case of pure gallium, the study also evaluates under the same conditions established for the gallium, the melting process of commercial paraffin wax (organic compound) and of the calcium chloride hexahydrate (CaCl₂ 6H₂O-inorganic compound). In the present work, it is adopted the best options that have been established by several researchers in their parametric studies with respect to this type of LTES, which lead to high values of thermal efficiency. To do so, concerning with the geometric aspects, one considers a gap of the channel formed by two consecutive slabs, thickness and length of the slab. About the HTF, one considers the type of fluid, the mass flow rate, and inlet temperature.

Keywords: flat slab, heat storing, pure metal, solid subcooling

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Authors: Eunsu Jang, Kang Park

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In developing an armored ground combat vehicle (AGCV), it is a very important step to analyze the vulnerability (or the survivability) of the AGCV against enemy’s attack. In the vulnerability analysis, the penetration equations are usually used to get the penetration depth and check whether a bullet can penetrate the armor of the AGCV, which causes the damage of internal components or crews. The penetration equations are derived from penetration experiments which require long time and great efforts. However, they usually hold only for the specific material of the target and the specific type of the bullet used in experiments. Thus, penetration simulation using ANSYS can be another option to calculate penetration depth. However, it is very important to model the targets and select the input parameters in order to get an accurate penetration depth. This paper performed a sensitivity analysis of input parameters of ANSYS on the accuracy of the calculated penetration depth. Two conflicting objectives need to be achieved in adopting ANSYS in penetration analysis: maximizing the accuracy of calculation and minimizing the calculation time. To maximize the calculation accuracy, the sensitivity analysis of the input parameters for ANSYS was performed and calculated the RMS error with the experimental data. The input parameters include mesh size, boundary condition, material properties, target diameter are tested and selected to minimize the error between the calculated result from simulation and the experiment data from the papers on the penetration equation. To minimize the calculation time, the parameter values obtained from accuracy analysis are adjusted to get optimized overall performance. As result of analysis, the followings were found: 1) As the mesh size gradually decreases from 0.9 mm to 0.5 mm, both the penetration depth and calculation time increase. 2) As diameters of the target decrease from 250mm to 60 mm, both the penetration depth and calculation time decrease. 3) As the yield stress which is one of the material property of the target decreases, the penetration depth increases. 4) The boundary condition with the fixed side surface of the target gives more penetration depth than that with the fixed side and rear surfaces. By using above finding, the input parameters can be tuned to minimize the error between simulation and experiments. By using simulation tool, ANSYS, with delicately tuned input parameters, penetration analysis can be done on computer without actual experiments. The data of penetration experiments are usually hard to get because of security reasons and only published papers provide them in the limited target material. The next step of this research is to generalize this approach to anticipate the penetration depth by interpolating the known penetration experiments. This result may not be accurate enough to be used to replace the penetration experiments, but those simulations can be used in the early stage of the design process of AGCV in modelling and simulation stage.

Keywords: ANSYS, input parameters, penetration depth, sensitivity analysis

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Authors: Osk Dagsdottir

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Background—Gait classifying allows clinicians to differentiate gait patterns into clinically important categories that help in clinical decision making. Reliable comparison of gait data between normal and patients requires knowledge of the gait parameters of normal children's specific age group. However, there is still a lack of the gait database for normal children of different ages. Objectives—This study aims to investigate the kinematics of the lower limb joints during gait for normal children in different age groups. Methods—Fifty-three normal children (34 boys, 19 girls) were recruited in this study. All the children were aged between 5 to 16 years old. Age groups were defined as three types: young child aged (5-7), child (8-11), and adolescent (12-16). When a participant agreed to take part in the project, their parents signed a consent form. Vicon® motion capture system was used to collect gait data. Participants were asked to walk at their comfortable speed along a 10-meter walkway. Each participant walked up to 20 trials. Three good trials were analyzed using the Vicon Plug-in-Gait model to obtain parameters of the gait, e.g., walking speed, cadence, stride length, and joint parameters, e.g., joint angle, force, moments, etc. Moreover, each gait cycle was divided into 8 phases. The range of motion (ROM) angle of pelvis, hip, knee, and ankle joints in three planes of both limbs were calculated using an in-house program. Results—The temporal-spatial variables of three age groups of normal children were compared between each other; it was found that there was a significant difference (p < 0.05) between the groups. The step length and walking speed were gradually increasing from young child to adolescent, while cadence was gradually decreasing from young child to adolescent group. The mean and standard deviation (SD) of the step length of young child, child and adolescent groups were 0.502 ± 0.067 m, 0.566 ± 0.061 m and 0.672 ± 0.053 m, respectively. The mean and SD of the cadence of the young child, child and adolescent groups were 140.11±15.79 step/min, 129±11.84 step/min, and a 115.96±6.47 step/min, respectively. Moreover, it was observed that there were significant differences in kinematic parameters, either whole gait cycle or each phase. For example, RoM of knee angle in the sagittal plane in the whole cycle of young child group is (65.03±0.52 deg) larger than child group (63.47±0.47 deg). Conclusion—Our result showed that there are significant differences between each age group in the gait phases and thus children walking performance changes with ages. Therefore, it is important for the clinician to consider the age group when analyzing the patients with lower limb disorders before any clinical treatment.

Keywords: action research, creative learning, mathematics education, professional development

Procedia PDF Downloads 108

Authors: Rebecca Greenberg, Nipa Chauhan, Rashad Rehman

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Paternalism, in its traditional form, seems largely incompatible with Western medicine. In contrast, Family-Centred Care, a partial response to historically authoritative paternalism, carries its own challenges, particularly when operationalized as family-directed care. Specifically, in neonatology, decision-making is left entirely to Substitute Decision Makers (most commonly parents). Most models of shared decision-making employ both the parents’ and medical team’s perspectives but do not recognize the inherent asymmetry of information and experience – asking parents to act like physicians to evaluate technical data and encourage physicians to refrain from strong medical opinions and proposals. They also do not fully appreciate the difficulties in adjudicating which perspective to prioritize and, moreover, how to mitigate disagreement. Introducing a mild form of paternalism can harness the unique skillset both parents and clinicians bring to shared decision-making and ultimately work towards decision-making in the best interest of the child. The notion expressed here is that within the model of shared decision-making, mild paternalism is prioritized inasmuch as optimal care is prioritized. This mild form of paternalism is known as Beneficent Paternalism and justifies our encouragement for physicians to root down in their own medical expertise to propose treatment plans informed by medical expertise, standards of care, and the parents’ values. This does not mean that we forget that paternalism was historically justified on ‘beneficent’ grounds; however, our recommendation is that a re-integration of mild paternalism is appropriate within our current Western healthcare climate. Through illustrative examples from the NICU, this paper explores the appropriateness and merits of Beneficent Paternalism and ultimately its use in promoting family-centered care, patient’s best interests and reducing moral distress. A distinctive feature of the NICU is the fact that communication regarding a patient’s treatment is exclusively done with substitute decision-makers and not the patient, i.e., the neonate themselves. This leaves the burden of responsibility entirely on substitute decision-makers and the clinical team; the patient in the NICU does not have any prior wishes, values, or beliefs that can guide decision-making on their behalf. Therefore, the wishes, values, and beliefs of the parent become the map upon which clinical proposals are made, giving extra weight to the family’s decision-making responsibility. This leads to why Family Directed Care is common in the NICU, where shared decision-making is mandatory. However, the zone of parental discretion is not as all-encompassing as it is currently considered; there are appropriate times when the clinical team should strongly root down in medical expertise and perhaps take the lead in guiding family decision-making: this is just what it means to adopt Beneficent Paternalism.

Keywords: care, ethics, expertise, NICU, paternalism

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Authors: Shailendra Kumar Singh

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With the rise of New Linguistic World Order in the 21st century, the Aged Pragmatics is palpitating on the edge of theoretical irrelevance. What appears to be a new sociolinguistic reality is that the enlightening combination of alternative west, inclusive globalization and techno-revolution is adding novel recipes to communicative actions, style and gain among new linguistic breed which is being neither dominated nor powered by the western supremacy. The paper has the following main, interrelated, aims: it is intended to introduce the concept of alternative pragmatics that can offer what exactly is needed for our emerging societal realities; it asserts as to how the basic pillar of linguistic success in the new linguistic world order rests upon linguistic temptation and calibration of all; and it also reviews an inevitability of emerging economies in shaping the communication trends at a time when the western world is struggling to maintain the same control on the others exercised in the past. In particular, the paper seeks answers for the following questions: (a) Do we need an alternative pragmatics, one with alternativist leaning in an era of inclusive globalization and alternative west? (b) What are the pulses of shift which are encapsulating emergence of new communicative behavior among the new linguistic breed by breaking yesterday’s linguistic rigidity? (c) Or, what are those shifts which are making linguistic shift more perceptible? (d) Is New Linguistic World Order succeeding in reversing linguistic priorities of `who speaks, what language, where, how, why, to whom and in which condition’ with no parallel in the history? (e) What is explicit about the contemporary world of 21st century which makes linguistic world all exciting and widely celebrative phenomenon and that is also forced into our vision? (f) What factors will hold key to the future of yesterday’s `influential languages’ and today’s `emerging languages’ as world is in the paradigm transition? (g) Is the collapse of Aged Pragmatics good for the 21st century for understanding the difference between pragmatism of old linguistic world and new linguistic world order? New Linguistic world Order today, unlike in the past, is about a branding of new world with liberal world view for a particular form of ideal to be imagined in the 21st century. At this time without question it is hope that a new set of ideals with popular vocabulary will become the implicit pragmatic model as one of benign majoritarianism in all aspects of sociolinguistic reality. It appears to be a reality that we live in an extraordinary linguistic world with no parallel in the past. In particular, the paper also highlights the paradigm shifts: Demographic, Social-psychological, technological and power. These shifts are impacting linguistic shift which is unique in itself. The paper will highlight linguistic shift in details in which alternative west plays a major role without challenging the west because it is an era of inclusive globalization in which almost everyone takes equal responsibility.

Keywords: inclusive globalization, new linguistic world order, linguistic shift, world order

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Authors: Marcin Stasiulewicz, Sebastian Filipkowski, Aneta Panuszko

Abstract:

Background: The hallmark of neurodegenerative diseases, including Alzheimer's and Parkinson's diseases, is an aggregation of the abnormal forms of peptides and proteins. Water is essential to functioning biomolecules, and it is one of the key factors influencing protein folding and misfolding. However, the hydration studies of proteins are complicated due to the complexity of protein systems. The use of model compounds can facilitate the interpretation of results involving larger systems. Objectives: The goal of the research was to characterize the properties of the hydration water surrounding the two three-residue K peptide fragments INS (Isoleucine - Asparagine - Serine) and NSR (Asparagine - Serine - Arginine). Methods: Fourier-transform infrared spectra of aqueous solutions of the tripeptides were recorded on Nicolet 8700 spectrometer (Thermo Electron Co.) Measurements were carried out at 25°C for varying molality of solute. To remove oscillation couplings from water spectra and, consequently, obtain narrow O-D semi-heavy water bands (HDO), the isotopic dilution method of HDO in H₂O was used. The difference spectra method allowed us to isolate the tripeptide-affected HDO spectrum. Results: The structural and energetic properties of water affected by the tripeptides were compared to the properties of pure water. The shift of the values of the gravity center of bands (related to the mean energy of water hydrogen bonds) towards lower values with respect to the ones corresponding to pure water suggests that the energy of hydrogen bonds between water molecules surrounding tripeptides is higher than in pure water. A comparison of the values of the mean oxygen-oxygen distances in water affected by tripeptides and pure water indicates that water-water hydrogen bonds are shorter in the presence of these tripeptides. The analysis of differences in oxygen-oxygen distance distributions between the tripeptide-affected water and pure water indicates that around the tripeptides, the contribution of water molecules with the mean energy of hydrogen bonds decreases, and simultaneously the contribution of strong hydrogen bonds increases. Conclusions: It was found that hydrogen bonds between water molecules in the hydration sphere of tripeptides are shorter and stronger than in pure water. It means that in the presence of the tested tripeptides, the structure of water is strengthened compared to pure water. Moreover, it has been shown that in the vicinity of the Asparagine - Serine - Arginine, water forms stronger and shorter hydrogen bonds. Acknowledgments: This work was funded by the National Science Centre, Poland (grant 2017/26/D/NZ1/00497).

Keywords: amyloids, K-peptide, hydration, FTIR spectroscopy

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