Search results for: labor efficiency
6699 Proposal of Optimality Evaluation for Quantum Secure Communication Protocols by Taking the Average of the Main Protocol Parameters: Efficiency, Security and Practicality
Authors: Georgi Bebrov, Rozalina Dimova
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In the field of quantum secure communication, there is no evaluation that characterizes quantum secure communication (QSC) protocols in a complete, general manner. The current paper addresses the problem concerning the lack of such an evaluation for QSC protocols by introducing an optimality evaluation, which is expressed as the average over the three main parameters of QSC protocols: efficiency, security, and practicality. For the efficiency evaluation, the common expression of this parameter is used, which incorporates all the classical and quantum resources (bits and qubits) utilized for transferring a certain amount of information (bits) in a secure manner. By using criteria approach whether or not certain criteria are met, an expression for the practicality evaluation is presented, which accounts for the complexity of the QSC practical realization. Based on the error rates that the common quantum attacks (Measurement and resend, Intercept and resend, probe attack, and entanglement swapping attack) induce, the security evaluation for a QSC protocol is proposed as the minimum function taken over the error rates of the mentioned quantum attacks. For the sake of clarity, an example is presented in order to show how the optimality is calculated.Keywords: quantum cryptography, quantum secure communcation, quantum secure direct communcation security, quantum secure direct communcation efficiency, quantum secure direct communcation practicality
Procedia PDF Downloads 1826698 Simulation of Improving the Efficiency of a Fire-Tube Steam Boiler
Authors: Roudane Mohamed
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In this study we are interested in improving the efficiency of a steam boiler to 4.5T/h and minimize fume discharge temperature by the addition of a heat exchanger against the current in the energy system, the output of the boiler. The mathematical approach to the problem is based on the use of heat transfer by convection and conduction equations. These equations have been chosen because of their extensive use in a wide range of application. A software and developed for solving the equations governing these phenomena and the estimation of the thermal characteristics of boiler through the study of the thermal characteristics of the heat exchanger by both LMTD and NUT methods. Subsequently, an analysis of the thermal performance of the steam boiler by studying the influence of different operating parameters on heat flux densities, temperatures, exchanged power and performance was carried out. The study showed that the behavior of the boiler is largely influenced. In the first regime (P = 3.5 bar), the boiler efficiency has improved significantly from 93.03 to 99.43 at the rate of 6.47% and 4.5%. For maximum speed, the change is less important, it is of the order of 1.06%. The results obtained in this study of great interest to industrial utilities equipped with smoke tube boilers for the preheating air temperature intervene to calculate the actual temperature of the gas so the heat exchanged will be increased and minimize temperature smoke discharge. On the other hand, this work could be used as a model of computation in the design process.Keywords: numerical simulation, efficiency, fire tube, heat exchanger, convection and conduction
Procedia PDF Downloads 2166697 Performance Evaluation of Conical Solar Concentrator System with Different Flow Rate
Authors: Gwi Hyun Lee, Mun Soo Na
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Solar energy has many advantages of infinite and clean source, and also it can be used for reduction of greenhouse gases and environment pollution. Concentrated solar system is a very useful to achieve reasonably high thermal efficiency. Different types of solar concentrating systems have been developed such as parabolic trough and parabolic dish. Conical solar concentrator is one of the most reliable and promising renewable energy systems for higher temperature applications. The objectives of this study were to investigate the influence of flow rate affecting the thermal efficiency of a conical solar collector, which has a double tube absorber placed at focal axis for collecting solar radiation. A conical solar concentrator consists of a conical reflector, which reflects direct solar radiation into an absorber. A double tube absorber was placed at the center of focal axis for collecting the solar radiation reflected from a conical reflector. A dual tracking system consists of a linear actuator and slew drive with driving cycle of 6 seconds. Water was used as circulating fluid, which flows from inlet to outlet of an absorber for collecting solar radiation. Three identical conical solar concentrator systems were installed side by side at the same place for the accurate performance analysis under the same environmental conditions. Performance evaluations were carried out with different volumetric flow rate of 2, 4 and 6 L/min to find the influence of flow rate affecting on thermal efficiency. The results indicated that average thermal efficiency was 73.24%, 81.96%, and 79.78% for each flow rate of 2 L/min, 4 L/min, and 6 L/min. It shows that the flow rate of circulating water has a significant effect on the thermal efficiency of the conical solar concentrator. It is concluded that an optimum flow rate of conical solar concentrator is 6 L/min.Keywords: conical solar concentrator, performance evaluation, solar energy, solar energy system
Procedia PDF Downloads 2776696 Predictors, Barriers, and Facilitators to Refugee Women’s Employment and Economic Inclusion: A Mixed Methods Systematic Review
Authors: Areej Al-Hamad, Yasin Yasin, Kateryna Metersky
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This mixed-method systematic review and meta-analysis provide an encompassing understanding of the barriers, facilitators, and predictors of refugee women's employment and economic inclusion. The study sheds light on the complex interplay of sociocultural, personal, political, and environmental factors influencing these outcomes, underlining the urgent need for a multifaceted, tailored approach to devising strategies, policies, and interventions aimed at boosting refugee women's economic empowerment. Our findings suggest that sociocultural factors, including gender norms, societal attitudes, language proficiency, and social networks, profoundly shape refugee women's access to and participation in the labor market. Personal factors such as age, educational attainment, health status, skills, and previous work experience also play significant roles. Political factors like immigration policies, regulations, and rights to work, alongside environmental factors like labor market conditions, availability of employment opportunities, and access to resources and support services, further contribute to the complex dynamics influencing refugee women's economic inclusion. The significant variability observed in the impacts of these factors across different contexts underscores the necessity of adopting population and region-specific strategies. A one-size-fits-all approach may prove to be ineffective due to the diversity and unique circumstances of refugee women across different geographical, cultural, and political contexts. The study's findings have profound implications for policy-making, practice, education, and research. The insights garnered a call for coordinated efforts across these domains to bolster refugee women's economic participation. In policy-making, the findings necessitate a reassessment of current immigration and labor market policies to ensure they adequately support refugee women's employment and economic integration. In practice, they highlight the need for comprehensive, tailored employment services and interventions that address the specific barriers and leverage the facilitators identified. In education, they underline the importance of language and skills training programs that cater to the unique needs and circumstances of refugee women. Lastly, in research, they emphasize the need for ongoing investigations into the multifaceted factors influencing refugee women's employment experiences, allowing for continuous refinement of our understanding and interventions. Through this comprehensive exploration, the study contributes to ongoing efforts aimed at creating more inclusive, equitable societies. By continually refining our understanding of the complex factors influencing refugee women's employment experiences, we can pave the way toward enhanced economic empowerment for this vulnerable population.Keywords: refugee women, employment barriers, systematic review, employment facilitators
Procedia PDF Downloads 786695 Pyroelectric Effect on Thermoelectricity of AlInN/GaN Heterostructures
Authors: B. K. Sahoo
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Superior thermoelectric (TE) efficiency of AlₓIn₁₋ₓN /GaN heterostructure (HS) requires a minimum value of thermal conductivity (k). A smaller k would lead to even further increase of TE figure of merit (ZT). The built-in polarization (BIP) electric field of AlₓIn₁₋ₓN /GaN HS enhances S, and σ of the HS, however, the effect of BIP field on k of the HS has not been explored. Study of thermal conductivities (k: without BIP and kp: including BIP) vs temperature predicts pyroelectric behavior of HS. Both k and kp show crossover at a temperature Tp. The result shows that below Tp, kp < k due to negative thermal expansion coefficient (TEC). However, above Tp, kp > k. Above Tp, piezoelectric polarization dominates over spontaneous polarization due to positive TEC. This generates more lattice mismatch resulting in the significant contribution of BIP field to thermal conductivity. Thus, Tp can be considered as primary pyroelectric transition temperature of the material as above Tp thermal expansion takes place which is the reason for the secondary pyroelectric effect. It is found that below Tp, kp is decreased; thus enhancing TE efficiency. For x=0.1, 0.2 and 0.3; Tp are close to 200, 210 and 260 K, respectively. Thus, k of the HS can be modified as per requirement by tailoring the Al composition; making it suitable simultaneously for the design of high-temperature pyroelectric sensors and TE module for maximum power production.Keywords: AlₓIn₁₋ₓN/GaN heterostructure, built in polarization, pyroelectric behavior, thermoelectric efficiency
Procedia PDF Downloads 1186694 A Study on the Impact of Employment Status of the Elderly on Their Mental Well-Being in India
Authors: Santosh B. Phad, Priyanka V. Janbandhu, Dhananjay W. Bansod
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Population Ageing is a growing concern for the social scientists. There is a higher level of aged male participation compared to elderly females. Now, the critical question is whether participation in work improves the quality of life among the elderly and the impact of working status on the mental well-being of the elderly. While examining these research questions, the present paper focuses on the workforce participation of the elderly and the reasons behind it, additionally, determines the association between employment status and the mental well-being of the elderly. The present study has a base of two data sources. First one is Census of India data, 2001 and 2011, and another one is – the Study on Global Ageing and Adult Health (SAGE), a survey conducted in 2007. To capture the trend of workforce participation elderly Census data is significant and to obtain other information associated with this issue the SAGE data is studied. The research piece consists of univariate and bivariate analysis along with some statistical methods like principal component analysis (PCA) and regression modeling – to investigate the association between workforce participation of elderly and subjective well-being (SWB). The results show that the percentage of elderly participating in the labor market is gradually reducing, but the share of working elderly has increased within the group of overall workers. i.e., the ratio of aged workers to non-aged workers is rising. The findings from survey data specify that there is a considerable share of the elderly in the labor market; three-fourths of the employed elderly enrolled the workforce unwillingly. They are in need of some earnings mainly to afford the medical expenses on their health or the health of their spouse, also to support their family members who are economically inactive. Apart from need, duration of working is another vital aspect for the elderly, whereas more than 80 percent of the elderly are working for six hours or more, and most of them engaged in self-employment. However, more than one-third of the working elderly falls into a negative cluster of the subjective well-being (SWB) index, and it is consistent with the result of the discriminant analysis. Here, the SWB index calculated from the 12 items and the reliability score of these items is 0.89.Keywords: ageing, workforce, census of India, SAGE
Procedia PDF Downloads 1506693 Synthesis and Characterization of TiO₂, N Doped TiO₂ and AG Doped TiO₂ for Photocatalytic Degradation of Methylene Blue in Adwa Almeda Textile Industry, Tigray, Ethiopia
Authors: Mulugeta Gurum Gerechal
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Nowadays, the photocatalytic mechanism of water purification using nanoparticles has gained wider acceptance. For this purpose, the crystal form of N- TiO₂ and Ag-TiO₂ was prepared from TiCl₄, urea, NH₄OH, and AgNO₃ by sol-gel method and simple solid phase reaction followed by calcination at a temperature of 400°C for 4h at each. The synthesized photocatalysts were characterized using XRD, SEM, and UV-visible diffuse reflectance spectra. In the experiment, it was found that the absorption edge of N-TiO₂ was an efficient shift to visible light as compared to Ag-TiO₂. The XRD diffraction makes the particle size of N-TiO₂ smaller than Ag-TiO₂. The effect of catalyst loading and the effect of temperature on the photocatalytic efficiency of the prepared samples was tested using methylene blue as a target pollutant. The photocatalytic degradation efficiency of the catalysts for methylene blue was increased from 57.05 to 96.02% under solar radiation as the amount of the catalyst increased from 0.15 to 0.45 gram for N-TiO₂. Similarly, photocatalytic degradation of methylene blue was increased from 40.32 to 81.21% as the amount of Ag-TiO₂ increased from 0.05g to 0.1g. In addition, the photocatalytic degradation efficiency of the catalysts for the removal of methylene blue was increased from 58.00 to 98.00 and 47.00 to 81.21% under solar radiation as the calcination temperature of the catalyst increased from 300 to 500 for N-TiO₂ for Ag-TiO₂ 300 to 400⁰C. However, a further increase in catalyst loading and calcination temperature was found to decrease the degradation efficiency.Keywords: photocatalysis, degradation, nanoparticles, catalyst loading, calcination, methylene blue
Procedia PDF Downloads 86692 The Social Justice of Movement: Undocumented Immigrant Coalitions in the United States
Authors: Libia Jiménez Chávez
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This is a study of freedom riders and their courageous journey for civil rights, but the year was not 1961. It was 2003. This paper chronicles the emergence of a new civil rights movement for immigrant rights through an oral history of the 2003 U.S. Immigrant Workers Freedom Ride (IWFR). During the height of the post-9/11 immigrant repression, a bloc of organizations inspired by the Civil Rights Movement of the 1960s mobilized 900 multinational immigrants and their allies in the fight for legal status, labor protections, family reunification, and civil rights. The activists visited over 100 U.S. cities, met with Congressional leaders in the nation’s capital, and led a rally of over 50,000 people in New York City. This unified effort set the groundwork for the national May Day immigration protests of 2006. Movements can be characterized in two distinct ways: physical movement and social movements. In the past, historians have considered immigrants both as people and as participants in social movements. In contrast, studies of recent migrants tend to say little about their involvement in immigrant political mobilizations. The dominant literature on immigration portrays immigrants as objects of exclusion, border enforcement, detention, and deportation instead of strategic political actors. This paper aims to change this perception. It considers the Freedom Riders both as immigrants who were literally on the move and as participants in a social movement. Through interviews with participants and archival video footage housed at the University of California Los Angeles, it is possible to study this mobile protest as a movement. This contemporary immigrant struggle is an opportunity to explore the makeup and development of a heterogenous immigrant coalition and consider the relationship between population movements and social justice. In addition to oral histories and archival research, the study will utilize social movement literature, U.S. immigration and labor history, and Undocumented Critical Theory to expand the historiography of immigrant social movements in America.Keywords: civil rights, immigrant social movements, undocumented communities, undocumented critical theory
Procedia PDF Downloads 1696691 Enhancing Vehicle Efficiency Through Vapor Absorption Refrigeration Systems
Authors: Yoftahe Nigussie Worku
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This paper explores the utilization of vapor absorption refrigeration systems (VARS) as an alternative to the conventional vapor compression refrigerant systems (VCRS) in vehicle air conditioning (AC) systems. Currently, most vehicles employ VCRS, which relies on engine power to drive the compressor, leading to additional fuel consumption. In contrast, VARS harnesses low-grade heat, specifically from the exhaust of high-power internal combustion engines, reducing the burden on the vehicle's engine. The historical development of vapor absorption technology is outlined, dating back to Michael Faraday's discovery in 1824 and the subsequent creation of the first vapor absorption refrigeration machine by Ferdinand Carre in 1860. The paper delves into the fundamental principles of VARS, emphasizing the replacement of mechanical processes with physicochemical interactions, utilizing heat rather than mechanical work. The study compares the basic concepts of the current vapor compression systems with the proposed vapor absorption systems, highlighting the efficiency gains achieved by eliminating the need for engine-driven compressors. The vapor absorption refrigeration cycle (VARC) is detailed, focusing on the generator's role in separating and vaporizing ammonia, chosen for its low-temperature evaporation characteristics. The project's statement underscores the need for increased efficiency in vehicle AC systems beyond the limitations of VCRS. By introducing VARS, driven by low-grade heat, the paper advocates for a reduction in engine power consumption and, consequently, a decrease in fuel usage. This research contributes to the ongoing efforts to enhance sustainability and efficiency in automotive climate control systems.Keywords: VCRS, VARS, efficiency, sustainability
Procedia PDF Downloads 726690 Evaluating Learning Outcomes in the Implementation of Flipped Teaching Using Data Envelopment Analysis
Authors: Huie-Wen Lin
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This study integrated various teaching factors -based on the idea of a flipped classroom- in a financial management course. The study’s aim was to establish an effective teaching implementation strategy and evaluation mechanism with respect to learning outcomes, which can serve as a reference for the future modification of teaching methods. This study implemented a teaching method in five stages and estimated the learning efficiencies of 22 students (in the teaching scenario and over two semesters). Subsequently, data envelopment analysis (DEA) was used to compare, for each student, between the learning efficiencies before and after participation in the flipped classroom -in the first and second semesters, respectively- to identify the crucial external factors influencing learning efficiency. According to the results, the average overall student learning efficiency increased from 0.901 in the first semester to 0.967 in the second semester, which demonstrate that the flipped classroom approach can improve teaching effectiveness and learning outcomes. The results also revealed a difference in learning efficiency between male and female students.Keywords: data envelopment analysis, flipped classroom, learning outcome, teaching and learning
Procedia PDF Downloads 1556689 The Main Characteristics of Destructive Motivation
Authors: Elen Gasparyan, Naira Hakobyan
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One of the leading factors determining the effectiveness of work in a modern organization is the motivation of its employees. In the scientific psychological literature, this phenomenon is understood mainly as constructive forms of motivation and the search for ways to increase it. At the same time, the motivation of employees can sometimes lead to a decrease in the productivity of the organization, i.e., destructive motivation is usually not considered from the point of view of various motivational theories. This article provides an analysis of various forms of destructive motivation of employees. These forms include formalism in labor behavior, inadequate assessment of the work done, and an imbalance of personal and organizational interests. The destructive motivation of personnel has certain negative consequences both for the employees themselves and for the entire organization - it leads to a decrease in the rate of production and the quality of products or services, increased conflict in the behavior of employees, etc. Currently, there is an increase in scientific interest in the study of destructive motivation. The subject of psychological research is not only modern socio-psychological processes but also the achievements of scientific thought in the field of theories of motivation and management. This article examines the theoretical approaches of J. S. Adams and Porter-Lawler, provides an analysis of theoretical concepts, and emphasizes the main characteristics of the destructiveness of motivation. Destructive work motivation is presented at the macro, meso, and micro levels. These levels express various directions of development of motivation stimuli, such as social, organizational, and personal ones. At the macro level, the most important characteristics of destructive motivation are the high-income gap between employers and employees, а high degree of unemployment, weak social protection of workers, non-compliance by employers with labor legislation, and emergencies. At the organizational level, the main characteristics are decreasing the diversity of work and insufficient work conditions. At the personal level, the main characteristic of destructive motivation is a discrepancy between personal and organizational interests. A comparative analysis of the theoretical and methodological foundations of the study of motivation makes it possible to identify not only the main characteristics of destructive motivation but also to determine the contours of psychological counseling to reduce destructiveness in the behavior of employees.Keywords: destructive, motivation, organization, behavior
Procedia PDF Downloads 416688 Simulation of Government Management Model to Increase Financial Productivity System Using Govpilot
Authors: Arezou Javadi
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The use of algorithmic models dependent on software calculations and simulation of new government management assays with the help of specialized software had increased the productivity and efficiency of the government management system recently. This has caused the management approach to change from the old bitch & fix model, which has low efficiency and less usefulness, to the capable management model with higher efficiency called the partnership with resident model. By using Govpilot TM software, the relationship between people in a system and the government was examined. The method of two tailed interaction was the outsourcing of a goal in a system, which is formed in the order of goals, qualified executive people, optimal executive model, and finally, summarizing additional activities at the different statistical levels. The results showed that the participation of people in a financial implementation system with a statistical potential of P≥5% caused a significant increase in investment and initial capital in the government system with maximum implement project in a smart government.Keywords: machine learning, financial income, statistical potential, govpilot
Procedia PDF Downloads 876687 Simulation of Government Management Model to Increase Financial Productivity System Using Govpilot
Authors: Arezou Javadi
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The use of algorithmic models dependent on software calculations and simulation of new government management assays with the help of specialized software had increased the productivity and efficiency of the government management system recently. This has caused the management approach to change from the old bitch & fix model, which has low efficiency and less usefulness, to the capable management model with higher efficiency called the partnership with resident model. By using Govpilot TM software, the relationship between people in a system and the government was examined. The method of two tailed interaction was the outsourcing of a goal in a system, which is formed in the order of goals, qualified executive people, optimal executive model, and finally, summarizing additional activities at the different statistical levels. The results showed that the participation of people in a financial implementation system with a statistical potential of P≥5% caused a significant increase in investment and initial capital in the government system with maximum implement project in a smart government.Keywords: machine learning, financial income, statistical potential, govpilot
Procedia PDF Downloads 696686 Enhancing the Efficiency of Organic Solar Cells Using Metallic Nanoparticles
Authors: Sankara Rao Gollu, Ramakant Sharma, G. Srinivas, Souvik Kundu, Dipti Gupta
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In recent years, bulk heterojunction organic solar cells (BHJ OSCs) based on polymer–fullerene attracted a large research attention due to their numerous advantages such as light weight, easy processability, eco-friendly, low-cost, and capability for large area roll-to-roll manufacturing. BHJ OSCs usually suffer from insufficient light absorption due to restriction on keeping thin ( < 150 nm) photoactive layer because of small exciton diffusion length ( ~ 10 nm) and low charge carrier mobilities. It is thus highly desirable that light absorption as well as charge transport properties are enhanced by alternative methods so as to improve the device efficiency. In this work, therefore, we have focused on the strategy of incorporating metallic nanostructures in the active layer or charge transport layer to enhance the absorption and improve the charge transport.Keywords: organic solar cell, efficiency, bulk heterojunction, polymer-fullerene
Procedia PDF Downloads 3966685 Assessment of Metal and Nano-Metal Doped TiO₂ Nanoparticles for Photocatalytic Degradation of Methylene Blue in Almeda Textile Industry, Tigray, Ethiopia
Authors: Mulugeta Gurum Gerechal
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Nowadays, the photocatalytic mechanism of water purification using nanoparticles has gained wider acceptance. For this purpose, the Crystal form of N- TiO₂ and Ag-TiO₂ was prepared from TiCl₄, Urea, NH₄OH and AgNO₃ by sol-gel method and simple solid phase reaction followed by calcination at a temperature of 400 °C for 4h at each. The synthesized photocatalysts were characterized using XRD, SEM and UV-visible diffuse reflectance spectra. In the experiment, it was found that the absorption edge of N-TiO₂ was a well efficient shift to visible light as compared to Ag-TiO₂. The XRD diffraction makes the particle size of N-TiO₂ smaller than Ag-TiO₂. The effect of catalyst loading and the effect of temperature on the photocatalytic efficiency of the prepared samples was tested using methylene blue as a target pollutant. The photocatalytic degradation efficiency of the catalysts for methylene blue was increased from 57.05 to 96.02% under solar radiation as the amount of the catalyst increased from 0.15 to 0.45 gram for N-TiO₂. Similarly, photocatalytic degradation of methylene blue was increased from 40.32 to 81.21% as the amount of Ag-TiO₂ increased from 0.05g to 0.1g. In addition, the photocatalytic degradation efficiency of the catalysts for the removal of methylene blue was increased from 58.00 to 98.00 and 47.00 to 81.21 % under solar radiation as the calcination temperature of the catalyst increased from 300 to 500 for N-TiO₂ for Ag-TiO₂ 300 to 4000C. However, a further increase in catalyst loading and calcination temperature was found to decrease the degradation efficiency.Keywords: photocatalysis, degradation, nanoparticles, catalyst loading, calcination and methylene blue
Procedia PDF Downloads 606684 The Youth Employment Peculiarities in Post-Soviet Georgia
Authors: M. Lobzhanidze, N. Damenia
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The article analyzes the current structural changes in the economy of Georgia, liberalization and integration processes of the economy. In accordance with this analysis, the peculiarities and the problems of youth employment are revealed. In the paper, the Georgian labor market and its contradictions are studied. Based on the analysis of materials, the socio-economic losses caused by the long-term and mass unemployment of young people are revealed, the objective and subjective circumstances of getting higher education are studied. The youth employment and unemployment rates are analyzed. Based on the research, the factors that increase unemployment are identified. According to the analysis of the youth employment, it has appeared that the unemployment share in the number of economically active population has increased in the younger age group. It demonstrates the high requirements of the labour market in terms of the quality of the workforce. Also, it is highlighted that young people are exposed to a highly paid job. The following research methods are applied in the presented paper: statistical (selection, grouping, observation, trend, etc.) and qualitative research (in-depth interview), as well as analysis, induction and comparison methods. The article presents the data by the National Statistics Office of Georgia and the Ministry of Agriculture of Georgia, policy documents of the Parliament of Georgia, scientific papers by Georgian and foreign scientists, analytical reports, publications and EU research materials on similar issues. The work estimates the students and graduates employment problems existing in the state development strategy and priorities. The measures to overcome the challenges are defined. The article describes the mechanisms of state regulation of youth employment and the ways of improving this regulatory base. As for major findings, it should be highlighted that the main problems are: lack of experience and incompatibility of youth qualification with the requirements of the labor market. Accordingly, it is concluded that the unemployment rate of young people in Georgia is increasing.Keywords: migration of youth, youth employment, migration management, youth employment and unemployment
Procedia PDF Downloads 1486683 Numerical Modeling of hybrid Photovoltaic-Thermoelectric Solar Unit by Applying Various Cross-Sections of Cooling Ducts
Authors: Ziba Khalili, Mohsen Sheikholeslami, Ladan Momayez
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Combining the photovoltaic/thermal (PVT) systems with a thermoelectric (TE) module can raise energy yields since the TE module boosts the system's energy conversion efficiency. In the current study, a PVT system integrated with a TE module was designed and simulated in ANSYS Fluent 19.2. A copper heat transfer tube (HTT) was employed for cooling the photovoltaic (PV) cells. Four different shapes of HTT cross-section, i.e., circular, square, elliptical, and triangular, with equal cross-section areas were investigated. Also, the influence of Cu-Al2O3/water hybrid nanofluid (0.024% volume concentration), fluid inlet velocity (uᵢ ), and amount of solar radiation (G), on the PV temperature (Tₚᵥ) and system performance were investigated. The ambient temperature (Tₐ), wind speed (u𝓌), and fluid inlet temperature (Tᵢ), were considered to be 25°C, 1 m/s, and 27°C, respectively. According to the obtained data, the triangular case had the greatest impact on reducing the compared to other cases. In the triangular case, examination of the effect of hybrid nanofluid showed that the use of hybrid nanofluid at 800 W/m2 led to a reduction of the TPV by 0.6% compared to water, at 0.19 m/s. Moreover, the thermal efficiency ( ) and the overall electrical efficiency (nₜ) of the system improved by 0.93% and 0.22%, respectively, at 0.19 m/s. In a triangular case where G and were 800 W/m2 and 19 m/s, respectively, the highest amount of, thermal power (Eₜ), and, were obtained as 72.76%, 130.84 W and 12.03%, respectively.Keywords: electrical performance, photovoltaic/thermal, thermoelectric, hybrid nanofluid, thermal efficiency
Procedia PDF Downloads 776682 On the Fourth-Order Hybrid Beta Polynomial Kernels in Kernel Density Estimation
Authors: Benson Ade Eniola Afere
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This paper introduces a family of fourth-order hybrid beta polynomial kernels developed for statistical analysis. The assessment of these kernels' performance centers on two critical metrics: asymptotic mean integrated squared error (AMISE) and kernel efficiency. Through the utilization of both simulated and real-world datasets, a comprehensive evaluation was conducted, facilitating a thorough comparison with conventional fourth-order polynomial kernels. The evaluation procedure encompassed the computation of AMISE and efficiency values for both the proposed hybrid kernels and the established classical kernels. The consistently observed trend was the superior performance of the hybrid kernels when compared to their classical counterparts. This trend persisted across diverse datasets, underscoring the resilience and efficacy of the hybrid approach. By leveraging these performance metrics and conducting evaluations on both simulated and real-world data, this study furnishes compelling evidence in favour of the superiority of the proposed hybrid beta polynomial kernels. The discernible enhancement in performance, as indicated by lower AMISE values and higher efficiency scores, strongly suggests that the proposed kernels offer heightened suitability for statistical analysis tasks when compared to traditional kernels.Keywords: AMISE, efficiency, fourth-order Kernels, hybrid Kernels, Kernel density estimation
Procedia PDF Downloads 696681 Time Driven Activity Based Costing Capability to Improve Logistics Performance: Application in Manufacturing Context
Authors: Siham Rahoui, Amr Mahfouz, Amr Arisha
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In a highly competitive environment characterised by uncertainty and disruptions, such as the recent COVID-19 outbreak, supply chains (SC) face the challenge of maintaining their cost at minimum levels while continuing to provide customers with high-quality products and services. More importantly, businesses in such an economic context strive to maintain survival by keeping the cost of undertaken activities (such as logistics) low and in-house. To do so, managers need to understand the costs associated with different products and services in order to have a clear vision of the SC performance, maintain profitability levels, and make strategic decisions. In this context, SC literature explored different costing models that sought to determine the costs of undertaking supply chain-related activities. While some cost accounting techniques have been extensively explored in the SC context, more contributions are needed to explore the potential of time driven activity-based costing (TDABC). More specifically, more applications are needed in the manufacturing context of the SC, where the debate is ongoing. The aim of the study is to assess the capability of the technique to assess the operational performance of the logistics function. Through a case study methodology applied to a manufacturing company operating in the automotive industry, TDABC evaluates the efficiency of the current configuration and its logistics processes. The study shows that monitoring the process efficiency and cost efficiency leads to strategic decisions that contributed to improve the overall efficiency of the logistics processes.Keywords: efficiency, operational performance, supply chain costing, time driven activity based costing
Procedia PDF Downloads 1626680 Enhancement of Light Out Efficiency of PLED Device Employing Designed Substrate Combined with Nano-Line Patterns
Authors: Ting-Ting Wen, H. C. Lin
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This paper reports a study for the light outcoupling efficiency of the PLED device. In use of a designed substrate combined with nano-line patterns in PLED device, the light outcoupling efficiency can be significantly enhanced. The designed substrate was made by UV imprinting technology, such as triangular microlens arrays on the front and periodic corrugated patterns on the back surface. The nano-line patterns in PLED device was fabricated by advanced microstamping and ink-jet printing techniques. For high angles of observation with respect to the substrate surface normal, the light out intensity of the developed PLED device is increased from 0.05 (a.u.) up to 0.69 (a.u.) at the view angle 85 degree. The designed integration leads to 64% increase of the light out intensity compared with the conventional PLED device.Keywords: triangular microlens, corrugation patterns, nano-line patterns, PLED device, UV imprinting technology, microstamping
Procedia PDF Downloads 4766679 Efficiency of Using E-Wallets as Payment Method in Marikina City During COVID-19 Pandemic
Authors: Noel Paolo Domingo, James Paul Menina, Laurente Ferrer
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Most people were forced to stay at home and limit their physical contact during the COVID-19 pandemic. Due to the situation, strict implementation of government policies and safety protocols encouraged consumers to utilize cashless or digital transactions through e-wallets. In this study, the researchers aim to investigate the efficiency of using e-wallets as a payment method during the COVID-19 pandemic in Marikina City. The study examined the efficiency of e-wallets in terms of Usefulness, Convenience, and Safety and Security based on respondents’ assessment. Questionnaires developed by the researchers were distributed to a total of 400 e-wallet users in Marikina City aged 15 years old and above to gather data by using a purposive sampling technique. The data collected was processed using SPSS version 26. Frequency, percentage, and mean were utilized to describe the profile of respondents and their assessment of e-wallets in terms of the three constructs. ANOVA and t-tests were also employed to test the significant differences in the respondent’s assessment when the demographic profile was considered. The study revealed that when it comes to usefulness, e-wallet is efficient while in terms of convenience, and safety and security, e-wallet has been proven to be very efficient. During the COVID-19 pandemic, utilizing e-wallets has been embraced by most consumers. By enhancing its features, more people will be satisfied with using e-wallets.Keywords: efficiency of e-wallets, usefulness, convenience, safety and security
Procedia PDF Downloads 1386678 Understanding the Performance and Loss Mechanisms in Ag Alloy CZTS Solar Cells: Photocurrent Generation, Charge Separation, and Carrier Transport
Authors: Kang Jian Xian, Huda Abdullah, Md. Akhtaruzzaman, Iskandar Yahya, Mohd Hafiz Dzarfan Othman, Brian Yulianto
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The CZTS absorber layer doped with a silver (Ag) is one of the candidates that suggest improving the efficiency of thin films. Silver element functions to reduce antisite defects, increase grain size and create the plasmonic effect. In this work, an experimental study has been done to investigate the electrical and physical properties of CZTS, ACZTS, and AZTS. Ag replaces the Cu in (Cu1-xAgx)2ZnSnS4 (ACZTS) is up to x ≤1. ACZTS thin-films solar cells have been deposited by sol–the gel spin coating method. There are a total of 19 samples done with 11 significant percentages (0%, 10%, 20%… 100%) to show the whole phenomena of efficiency rate and nine specific percentages to find out the best concentration rate for Ag-doped. The obtained results can be helpful for better understanding ACZTS layers.Keywords: CZTS, ACZTS, AZTS, silver, antisite, efficiency, thin-film solar cell
Procedia PDF Downloads 906677 Porous Bluff-Body Disc on Improving the Gas-Mixing Efficiency
Authors: Shun-Chang Yen, You-Lun Peng, Kuo-Ching San
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A numerical study on a bluff-body structure with multiple holes was conducted using ANSYS Fluent computational fluid dynamics analysis. The effects of the hole number and jet inclination angles were considered under a fixed gas flow rate and nonreactive gas. The bluff body with multiple holes can transform the axial momentum into a radial and tangential momentum as well as increase the swirl number (S). The concentration distribution in the mixing of a central carbon dioxide (CO2) jet and an annular air jet was utilized to analyze the mixing efficiency. Three bluff bodies with differing hole numbers (H = 3, 6, and 12) and three jet inclination angles (θ = 45°, 60°, and 90°) were designed for analysis. The Reynolds normal stress increases with the inclination angle. The Reynolds shear stress, average turbulence intensity, and average swirl number decrease with the inclination angle. For an unsymmetrical hole configuration (i.e., H = 3), the streamline patterns exhibited an unsymmetrical flow field. The highest mixing efficiency (i.e., the lowest integral gas fraction of CO2) occurred at H = 3. Furthermore, the highest swirl number coincided with the strongest effect on the mass fraction of CO2. Therefore, an unsymmetrical hole arrangement induced a high swirl flow behind the porous disc.Keywords: bluff body with multiple holes, computational fluid dynamics, swirl-jet flow, mixing efficiency
Procedia PDF Downloads 3556676 Preparation and Characterization of Chitosan Nanoparticles for Delivery of Oligonucleotides
Authors: Gyati Shilakari Asthana, Abhay Asthana, Dharm Veer Kohli, Suresh Prasad Vyas
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Purpose: The therapeutic potential of oligonucleotide (ODN) is primarily dependent upon its safe and efficient delivery to specific cells overcoming degradation and maximizing cellular uptake in vivo. The present study is focused to design low molecular weight chitosan nanoconstructs to meet the requirements of safe and effectual delivery of ODNs. LMW-chitosan is a biodegradable, water soluble, biocompatible polymer and is useful as a non-viral vector for gene delivery due to its better stability in water. Methods: LMW chitosan ODN nanoparticles (CHODN NPs) were formulated by self-assembled method using various N/P ratios (moles ratio of amine groups of CH to phosphate moieties of ODNs; 0.5:1, 1:1, 3:1, 5:1, and 7:1) of CH to ODN. The developed CHODN NPs were evaluated with respect to gel retardation assay, particle size, zeta potential and cytotoxicity and transfection efficiency. Results: Complete complexation of CH/ODN was achieved at the charge ratio of 0.5:1 or above and CHODN NPs displayed resistance against DNase I. On increasing the N/P ratio of CH/ODN, the particle size of the NPs decreased whereas zeta potential (ZV) value increased. No significant toxicity was observed at all CH concentrations. The transfection efficiency was increased on increasing N/P ratio from 1:1 to 3:1, whereas it was decreased with further increment in N/P ratio upto 7:1. Maximum transfection of CHODN NPs with both the cell lines (Raw 267.4 cells and Hela cells) was achieved at N/P ratio of 3:1. The results suggest that transfection efficiency of CHODN NPs is dependent on N/P ratio. Conclusion: Thus the present study states that LMW chitosan nanoparticulate carriers would be acceptable choice to improve transfection efficiency in vitro as well as in vivo delivery of oligonucleotide.Keywords: LMW-chitosan, chitosan nanoparticles, biocompatibility, cytotoxicity study, transfection efficiency, oligonucleotide
Procedia PDF Downloads 8486675 Subjectivities of the Inhabitants and Trajectories of Family Life in Vulnerable Groups
Authors: Mora Kestelman
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This paper analyzes various family groups of vulnerable populations as regards their family, educational, labor trajectory and sociability from a relational and historical approach based on archive research and fieldwork. Therefrom, their position and life projects are reconsidered as regards the planning and design of the habitat in which they are immersed. It concludes that a critical review of objectivity and subjectivity emphasizes the nonrational, often unconscious, forces that drive human and non-human relationships to configure identities, which, thus, permanently become constituent to the subjects.Keywords: social psychology, urban planning, self concept, social networks, identity theory
Procedia PDF Downloads 786674 Governance and Public Policy: The Perception of Efficiency and Equility in Brazil and South Africa
Authors: Paulino V. Tavares, Ana L. Romao
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Public governance represents an articulated arrangement, dynamic and interactive, present in the exercise of authority aimed at strengthening the decision-making procedure in public administration with transparency, accountability, responsiveness and capable of to emerge control and social empowerment, to pursue and achieve the objectives efficiently and with the effectiveness desired by the collective, respecting laws and providing social, institutional and economic equility in society. With this, using a multidimensional approach with the application of three questionnaires to a universe of twenty Counselors of the Courts of Auditors (Brazil), twenty professionals of public administration (Brazil), twenty Government/Provincial Counselors (South Africa), and twenty South African professionals of public administration, the present work aims to capture what is the perception about the efficiency and equility of public policies in Brazil and South Africa. With this, up until now, 30 responses have been obtained, and the results indicate that, in Brazil, 65% affirm due to the inefficiency of public policies, 70% point out that they do not believe in the equility of these same policies. In South Africa, the results indicate that 45% believe in government efficiency, and, with regard to the equility of public policies, 65% do not believe. In Brazil, the research reveals at least three reasons for this result, that is, lack of planning, lack of clear objectives of public policies, and lack of information on the part of society, while in South Africa, so far, research has not identified a specific reason for this result.Keywords: efficiency, equility, governance, public policy
Procedia PDF Downloads 1246673 Managing Expatriates' Return: Repatriation Practices in a Sample of Firms in Portugal
Authors: Ana Pinheiro, Fatima Suleman
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Literature has revealed strong awareness of companies in regard of expatriation, but issues associated with repatriation of employees after an international assignment have been overlooked. Repatriation is one of the most challenging human resource practices that affect how companies benefit from acquired skills and high potential employees; and gain competitive advantage through network developed during expatriation. However, empirical evidence achieved so far suggests that expatriates have been disappointed because companies lack an effective repatriation strategy. Repatriates’ professional and emotional needs are often unrecognized, while repatriation is perceived as a non-issue by companies. The underlying assumption is that the return to parent company, and original country, culture and language does not demand for any particular support. Unfortunately, this basic view has non-negligible consequences on repatriates, especially on expatriate retention and turnover rates after expatriation. The goal of our study is to examine the specific policies and practices adopted by companies to support employees after an international assignment. We assume that expatriation is process which ends with repatriation. The latter is such a crucial issue as the expatriation and require due attention through appropriate design of human resource management policies and tools. For this purpose, we use data from a qualitative research based on interviews to a sample of firms operating in Portugal. We attempt to compare how firms accommodate the concerns with repatriation in their policies and practices. Therefore, the interviews collect data on both expatriation and repatriation process, namely the selection and skills of candidates to expatriation, training, mentoring, communication and pay policies. Portuguese labor market seems to be an interesting case study for mainly two reasons. On the one hand, Portuguese Government is encouraging companies to internationalize in the context of an external market-oriented growth model. On the other hand, expatriation is being perceived as a job opportunity in the context of high unemployment rates of both skilled and non-skilled. This is an ongoing research and the data collected until now indicate that companies follow the pattern described in the literature. The interviewed companies recognize the higher relevance of repatriation process than expatriation, but disregard specific human resource policies. They have perceived that unfavorable labor market conditions discourage mobility across companies. It should be stressed that companies underline that employees enhanced the relevance of stable jobs and attach far less importance to career development and other benefits after expatriation. However, there are still cases of turnover and difficulties of retention. Managers’ report non-negligible cases of turnover associated with lack of effective repatriation programs and non-recognition of good performance. Repatriates seem to having acquired entrepreneurial spirit and skills and often create their own company. These results suggest that even in the context of worsening labor market conditions, there should be greater awareness of the need to retain talents, experienced and highly skills employees. Ultimately, other companies poach invaluable assets, while internationalized companies risk being training providers.Keywords: expatriates, expatriation, international management, repatriation
Procedia PDF Downloads 3366672 Investigating the Efficiency of Granular Sludge for Recovery of Phosphate from Wastewater
Authors: Sara Salehi, Ka Yu Cheng, Anna Heitz, Maneesha Ginige
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This study investigated the efficiency of granular sludge for phosphorous (P) recovery from wastewater. A laboratory scale sequencing batch reactor (SBR) was operated under alternating aerobic/anaerobic conditions to enrich a P accumulating granular biomass. This study showed that an overall 45-fold increase in P concentration could be achieved by reducing the volume of the P capturing liquor by 5-fold in the anaerobic P release phase. Moreover, different fractions of the granular biomass have different individual contributions towards generating a concentrated stream of P.Keywords: granular sludge, PAOs, P recovery, SBR
Procedia PDF Downloads 4806671 Smart Surveillance with 5G: A Performance Study in Adama City
Authors: Shenko Chura Aredo, Hailu Belay, Kevin T. Kornegay
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In light of Adama City’s smart city development vision, this study thoroughly investigates the performance of smart security systems with Fifth Generation (5G) network capabilities. It can be logistically difficult to install a lot of cabling, particularly in big or dynamic settings. Moreover, latency issues might affect linked systems, making it difficult for them to monitor in real time. Through a focused analysis that employs Adama City as a case study, the performance has been evaluated in terms of spectrum and energy efficiency using empirical data and basic signal processing formulations at different frequency resources. The findings also demonstrate that cameras working at higher 5G frequencies have more capacity than those operating at sub-6 GHz, notwithstanding frequency-related issues. It has also been noted that when the beams of such cameras are adaptively focussed based on the distance of the last cell edge user rather than the maximum cell radius, less energy is required than with conventional fixed power ramping.Keywords: 5G, energy efficiency, safety, smart security, spectral efficiency
Procedia PDF Downloads 176670 The Volume–Volatility Relationship Conditional to Market Efficiency
Authors: Massimiliano Frezza, Sergio Bianchi, Augusto Pianese
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The relation between stock price volatility and trading volume represents a controversial issue which has received a remarkable attention over the past decades. In fact, an extensive literature shows a positive relation between price volatility and trading volume in the financial markets, but the causal relationship which originates such association is an open question, from both a theoretical and empirical point of view. In this regard, various models, which can be considered as complementary rather than competitive, have been introduced to explain this relationship. They include the long debated Mixture of Distributions Hypothesis (MDH); the Sequential Arrival of Information Hypothesis (SAIH); the Dispersion of Beliefs Hypothesis (DBH); the Noise Trader Hypothesis (NTH). In this work, we analyze whether stock market efficiency can explain the diversity of results achieved during the years. For this purpose, we propose an alternative measure of market efficiency, based on the pointwise regularity of a stochastic process, which is the Hurst–H¨older dynamic exponent. In particular, we model the stock market by means of the multifractional Brownian motion (mBm) that displays the property of a time-changing regularity. Mostly, such models have in common the fact that they locally behave as a fractional Brownian motion, in the sense that their local regularity at time t0 (measured by the local Hurst–H¨older exponent in a neighborhood of t0 equals the exponent of a fractional Brownian motion of parameter H(t0)). Assuming that the stock price follows an mBm, we introduce and theoretically justify the Hurst–H¨older dynamical exponent as a measure of market efficiency. This allows to measure, at any time t, markets’ departures from the martingale property, i.e. from efficiency as stated by the Efficient Market Hypothesis. This approach is applied to financial markets; using data for the SP500 index from 1978 to 2017, on the one hand we find that when efficiency is not accounted for, a positive contemporaneous relationship emerges and is stable over time. Conversely, it disappears as soon as efficiency is taken into account. In particular, this association is more pronounced during time frames of high volatility and tends to disappear when market becomes fully efficient.Keywords: volume–volatility relationship, efficient market hypothesis, martingale model, Hurst–Hölder exponent
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