Search results for: Attention
1722 Hierarchical Porous Carbon Composite Electrode for High Performance Supercapacitor Application
Authors: Chia-Chia Chang, Jhen-Ting Huang, Hu-Cheng Weng, An-Ya Lo
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This study developed a simple hierarchical porous carbon (HPC) synthesis process and used for supercapacitor application. In which, mesopore provides huge specific surface area, meanwhile, macropore provides excellent mass transfer. Thus the hierarchical porous electrode improves the charge-discharge performance. On the other hand, cerium oxide (CeO2) have also got a lot research attention owing to its rich in content, low in price, environmentally friendly, good catalytic properties, and easy preparation. Besides, a rapid redox reaction occurs between trivalent cerium and tetravalent cerium releases oxygen atom and increase the conductivity. In order to prevent CeO2 from disintegration under long-term charge-discharge operation, the CeO2 carbon porous materials were was integrated as composite material in this study. For in the ex-situ analysis, scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electron microscope (TEM) analysis were adopted to identify the surface morphology, crystal structure, and microstructure of the composite. 77K Nitrogen adsorption-desorption analysis was used to analyze the porosity of each specimen. For the in-situ test, cyclic voltammetry (CV) and chronopotentiometry (CP) were conducted by potentiostat to understand the charge and discharge properties. Ragone plot was drawn to further analyze the resistance properties. Based on above analyses, the effect of macropores/mespores and the CeO2/HPC ratios on charge-discharge performance were investigated. As a result, the capacitance can be greatly enhanced by 2.6 times higher than pristine mesoporous carbon electrode.Keywords: hierarchical porous carbon, cerium oxide, supercapacitor
Procedia PDF Downloads 1231721 Executing the Law: The Practical Absence of Law and Its Effects on Death Row Inmates and Their Families in Egypt
Authors: Amira M. Othman
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Despite the massive array of literature that engages with the Egyptian legislative system on a theoretical level, very little attention has been dedicated to the comparison between the legislative clauses on the one hand, and the (absence of their) real-world implementation on the other. This paper starts with this discrepancy, focusing on the legal proceedings in some recent cases dubbed ‘political,’ in which defendants received death sentences. Then, it sheds light on the trend of practical disregard of the law on behalf of the criminal justice apparatuses (whether security forces, public prosecution offices, lawyers, judges, prison wardens, and executioners) through the examination of case files and the conduction of interviews with some defense lawyers in the cases in question. It also identifies the resultant state of confusion among prison staff, as manifest in their treatment of defendants even before the death sentences against them is pronounced; in other words, the application of some aspects of the law in certain cases, and their simultaneous disregard of others. Then, the paper explores the effects of such execution of the law on the death row inmates, as it identifies the different strategies through which defendants who are sentenced to death appropriate a number of legal clauses to their benefit, thereby embarrassing - or highly irritating - the judges that pronounce their death sentences. In addition to appropriation, other strategies include the contestation of the law and their presence before the courts in general, as well as the complete disregard and dismissal of the legal system altogether. Finally, the paper investigates the consequent conceptual effect on the first degree families of death row inmates, namely how their daily encounters with the Egyptian legislative system - particularly its emphasis on the absence of the otherwise binding local legislation - continue to shape their conceptions of the ‘law,’ of ‘justice,’ and their trust in the ‘state.’Keywords: death penalty, Egyptian law absence, justice, political cases
Procedia PDF Downloads 1751720 The Impact of Failure-tolerant Restaurant Culture on Curbing Employees’ Withdrawal Behavior: The Roles of Psychological Empowerment and Mindful Leadership
Authors: Omar Alsetoohy, Mohamed Ezzat, Mahmoud Abou Kamar
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The success of a restaurant or hotel depends very much on the quality and quantity of its human resources. Thus, establishing a competitive edge through human assets requires careful attention to the practices that best leverage these assets. Usually, hotel or restaurant employees recognize customer defection as an unfavorable or unpleasant occurrence associated with failure. These failures could be in handling, communication, learning, or encouragement. Besides, employees could be afraid of blame from their colleagues and managers, which prevents them from freely discussing these mistakes with them. Such behaviors, in turn, would push employees to withdraw from the workplace. However, we have a good knowledge of the leadership outcomes, but less is known about how and why these effects occur. Accordingly, mindful leaders usually analyze the causes and underlying mechanisms of failures for work improvement. However, despite the excessive literature in the field of leadership and employee behaviors, to date, no research studies had investigated the impact of a failure-tolerant restaurant culture on the employees’ withdrawal behaviors considering the moderating role of psychological empowerment and mindful leadership. Thus, this study seeks to investigate the impact of a failure-tolerant culture on the employees’ withdrawal behaviors in fast-food restaurants in Egypt considering the moderating effects of employee empowerment and mindful leaders. This study may contribute to the existing literature by filling the gap between failure-tolerant cultures and employee withdrawal behaviors in the hospitality literature. The study may also identify the best practices for restaurant operators and managers to deal with employees' failures as an improvement tool for their performance.Keywords: failure-tolerant culture, employees’ withdrawal behaviors psychological empowerment, mindful leadership, restaurants
Procedia PDF Downloads 1081719 Fall Prevention: Evidence-Based Intervention in Exercise Program Implementation for Keeping Older Adults Safe and Active
Authors: Jennifer Holbein, Maritza Wiedel
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Background: Aging is associated with an increased risk of falls in older adults, and as a result, falls have become public health crises. However, the incidence of falls can be reduced through healthy aging and the implementation of a regular exercise and strengthening program. Public health and healthcare professionals authorize the use of evidence‐based, exercise‐focused fall interventions, but there are major obstacles to translating and disseminating research findings into healthcare practices. The purpose of this study was to assess the feasibility of an intervention, A Matter of Balance, in terms of demand, acceptability, and implementation into current exercise programs. Subjects: Seventy-five participants from rural communities, above the age of sixty, were randomized to an intervention or attention-control of the standardized senior fitness test. Methods: Subject completes the intervention, which combines two components: (1) motivation and (2) fall-reducing physical activities with protocols derived from baseline strength and balanced assessments. Participants (n=75) took part in the program after completing baseline functional assessments as well as evaluations of their personal knowledge, health outcomes, demand, and implementation interventions. After 8-weeks of the program, participants were invited to complete follow-up assessments with results that were compared to their baseline functional analyses. Out of all the participants in the study who complete the initial assessment, approximately 80% are expected to maintain enrollment in the implemented prescription. Furthermore, those who commit to the program should show mitigation of fall risk upon completion of their final assessment.Keywords: aging population, exercise, falls, functional assessment, healthy aging
Procedia PDF Downloads 1031718 Important Factors Affecting the Effectiveness of Quality Control Circles
Authors: Sogol Zarafshan
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The present study aimed to identify important factors affecting the effectiveness of quality control circles in a hospital, as well as rank them using a combination of fuzzy VIKOR and Grey Relational Analysis (GRA). The study population consisted of five academic members and five experts in the field of nursing working in a hospital, who were selected using a purposive sampling method. Also, a sample of 107 nurses was selected through a simple random sampling method using their employee codes and the random-number table. The required data were collected using a researcher-made questionnaire which consisted of 12 factors. The validity of this questionnaire was confirmed through giving the opinions of experts and academic members who participated in the present study, as well as performing confirmatory factor analysis. Its reliability also was verified (α=0.796). The collected data were analyzed using SPSS 22.0 and LISREL 8.8, as well as VIKOR–GRA and IPA methods. The results of ranking the factors affecting the effectiveness of quality control circles showed that the highest and lowest ranks were related to ‘Managers’ and supervisors’ support’ and ‘Group leadership’. Also, the highest hospital performance was for factors such as ‘Clear goals and objectives’ and ‘Group cohesiveness and homogeneity’, and the lowest for ‘Reward system’ and ‘Feedback system’, respectively. The results showed that although ‘Training the members’, ‘Using the right tools’ and ‘Reward system’ were factors that were of great importance, the organization’s performance for these factors was poor. Therefore, these factors should be paid more attention by the studied hospital managers and should be improved as soon as possible.Keywords: Quality control circles, Fuzzy VIKOR, Grey Relational Analysis, Importance–Performance Analysis
Procedia PDF Downloads 1351717 Comparing Literary Publications about Corruption in South Africa to the Legal Position
Authors: Natasha Venter
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Recent publications, including Truth to Power by André de Ruyter, Gangster State by Pieter-Louis Myburgh, and Enemy of the People by Pieter du Toit and Adriaan Basson, expose alleged corrupt acts by high-ranking members of State, as well as those in charge of State-owned entities. These literary contributions have gripped the attention of a nation plagued by corruption scandals and the alleged misappropriation of state funds on an almost daily basis. The books, however, leave the populace with the burning question of why “nothing happens” to these individuals who are so directly implicated in the literature. The process followed by the State in the largest successful prosecution of a corrupt state official, Jackie Selebi, sheds some light as to how such high-ranking persons might be brought to book. The Supreme Court of Appeal’s definition of corruption and the interpretation of the facts (as presented by the State prosecutors) by the court is also valuable. Furthermore, some insight into the laws that criminalise corruption in South Africa, as well as applicable international instruments, is necessary. South Africa is ranked as the 70th most corrupt country out of 180 countries by Transparency International’s 2021 Corruption Perceptions Index. This is worrisome as South Africa is a signatory of the United Nations Convention Against Corruption (2004) and, as such, has certain international obligations to fulfil. However, if the political will to prosecute corrupt officials in South Africa exists, there are laws and instruments available to punish these individuals. This would not only vindicate the authors of literature about corruption in the country but also restore the hope of South Africans that, ultimately, crime does not pay.Keywords: corruption, eskom, state capture, government, literature, united nations, law, legal, Jackie selebi, supreme court of appeal
Procedia PDF Downloads 991716 Rethinking the Use of Online Dispute Resolution in Resolving Cross-Border Small E-Disputes in EU
Authors: Sajedeh Salehi, Marco Giacalone
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This paper examines the role of existing online dispute resolution (ODR) mechanisms and their effects on ameliorating access to justice – as a protected right by Art. 47 of the EU Charter of Fundamental Rights – for consumers in EU. The major focus of this study will be on evaluating ODR as the means of dispute resolution for Business-to-Consumer (B2C) cross-border small claims raised in e-commerce transactions. The authors will elaborate the consequences of implementing ODR methods in the context of recent developments in EU regulatory safeguards on promoting consumer protection. In this analysis, both non-judiciary and judiciary ODR redress mechanisms are considered, however, the significant consideration is given to – obligatory and non-obligatory – judiciary ODR methods. For that purpose, this paper will particularly investigate the impact of the EU ODR platform as well as the European Small Claims Procedure (ESCP) Regulation 861/2007 and their role on accelerating the access to justice for consumers in B2C e-disputes. Although, considerable volume of research has been carried out on ODR for consumer claims, rather less (or no-) attention has been paid to provide a combined doctrinal and empirical evaluation of ODR’s potential in resolving cross-border small e-disputes, in EU. Hence, the methodological approach taken in this study is a mixed methodology based on qualitative (interviews) and quantitative (surveys) research methods which will be mainly based on the data acquired through the findings of the Small Claims Analysis Net (SCAN) project. This project contributes towards examining the ESCP Regulation implementation and efficiency in providing consumers with a legal watershed through using the ODR for their transnational small claims. The outcomes of this research may benefit both academia and policymakers at national and international level.Keywords: access to justice, consumers, e-commerce, small e-Disputes
Procedia PDF Downloads 1281715 Biodegradable Polymer Composites of MOF-5 for Efficient and Sustained Delivery of Cephalexin and Metronidazole
Authors: Anoff Anim, Lila A. M. Mahmoud, Maria Katsikogianni, Sanjit Nayak
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Sustained and controlled delivery of antimicrobial drugs have been largely studied recently using metal organic frameworks (MOFs)and different polymers. However, much attention has not been given to combining both MOFs and biodegradable polymers, which would be a good strategy in providing a sustained gradual release of the drugs. Herein, we report a comparative study of the sustained and controlled release of widely used antibacterial drugs, cephalexin and metronidazole, from zinc-based MOF-5 incorporated in biodegradable polycaprolactone (PCL) and poly-lactic glycolic acid (PLGA) membranes. Cephalexin and metronidazole were separately incorporated in MOF-5 post-synthetically, followed by their integration into biodegradable PLGA and PCL membranes. The pristine MOF-5 and the loaded MOFs were thoroughly characterized by FT-IR, SEM, TGA and PXRD. Drug release studies were carried out to assess the release rate of the drugs in PBS and distilled water for up to 48 hours using UV-Vis Spectroscopy. Four bacterial strains from both the Gram-positive and Gram-negative types, Staphylococus aureus, Staphylococuss epidermidis, Escherichia coli, Acinetobacter baumanii, were tested against the pristine MOF, pure drugs, loaded MOFs and the drug-loaded MOF-polymer composites. Metronidazole-loaded MOF-5 composite of PLGA (PLGA-Met@MOF-5) was found to show highest efficiency to inhibit the growth of S. epidermidis compared to the other bacteria strains while maintaining a sustained minimum inhibitory concentration (MIC). This study demonstrates that the combination of biodegradable MOF-polymer composites can provide an efficient platform for sustained and controlled release of antimicrobial drugs and can be a potential strategy to integrate them in biomedical devices.Keywords: antimicrobial resistance, biodegradable polymers, cephalexin, drug release metronidazole, MOF-5, PCL, PLGA
Procedia PDF Downloads 1391714 Anticancer Effect of Resveratrol-Loaded Gelatin Nanoparticles in NCI-H460 Non-Small Cell Lung Carcinoma Cell Lines
Authors: N. Rajendra Prasad
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Resveratrol (RSV), a grape phytochemical, has drawn greater attention because of its beneficial ef-fects against cancer. However, RSV has some draw-backs such as unstabilization, poor water solubility and short biological half time, which limit the utili-zation of RSV in medicine, food and pharmaceutical industries. In this study, we have encapsulated RSV in gelatin nanoparticles (GNPs) and studied its anti-cancer efficacy in NCI-H460 lung cancer cells. SEM and DLS studies have revealed that the prepared RSV-GNPs possess spherical shape with a mean diameter of 294 nm. The successful encapsulation of RSV in GNPs has been achieved by the cross-linker glutaraldehyde probably through Schiff base reaction and hydrogen bond interaction. Spectrophotometric analysis revealed that the max-imum of 93.6% of RSV has been entrapped in GNPs. In vitro drug release kinetics indicated that there was an initial burst release followed by a slow and sustained release of RSV from GNPs. The prepared RSV-GNPs exhibited very rapid and more efficient cellular uptake than free RSV. Further, RSV-GNPs treatment showed greater antiproliferative efficacy than free RSV treatment in NCI-H460 cells. It has been found that greater ROS generation, DNA damage and apoptotic incidence in RSV-GNPs treated cells than free RSV treatment. Erythrocyte aggregation assay showed that the prepared RSV-GNPs formulation elicit no toxic response. HPLC analysis revealed that RSV-GNPs was more bioavailable and had a longer half-life than free RSV. Hence, GNPs carrier system might be a promising mode for controlled delivery and for improved therapeutic index of poorly water soluble RSV.Keywords: resveratrol, coacervation, anticancer gelatin nanoparticles, lung cancer, controlled release
Procedia PDF Downloads 4471713 Variable Refrigerant Flow (VRF) Zonal Load Prediction Using a Transfer Learning-Based Framework
Authors: Junyu Chen, Peng Xu
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In the context of global efforts to enhance building energy efficiency, accurate thermal load forecasting is crucial for both device sizing and predictive control. Variable Refrigerant Flow (VRF) systems are widely used in buildings around the world, yet VRF zonal load prediction has received limited attention. Due to differences between VRF zones in building-level prediction methods, zone-level load forecasting could significantly enhance accuracy. Given that modern VRF systems generate high-quality data, this paper introduces transfer learning to leverage this data and further improve prediction performance. This framework also addresses the challenge of predicting load for building zones with no historical data, offering greater accuracy and usability compared to pure white-box models. The study first establishes an initial variable set of VRF zonal building loads and generates a foundational white-box database using EnergyPlus. Key variables for VRF zonal loads are identified using methods including SRRC, PRCC, and Random Forest. XGBoost and LSTM are employed to generate pre-trained black-box models based on the white-box database. Finally, real-world data is incorporated into the pre-trained model using transfer learning to enhance its performance in operational buildings. In this paper, zone-level load prediction was integrated with transfer learning, and a framework was proposed to improve the accuracy and applicability of VRF zonal load prediction.Keywords: zonal load prediction, variable refrigerant flow (VRF) system, transfer learning, energyplus
Procedia PDF Downloads 281712 Factors Affecting At-Grade Railway Level Crossing Accidents in Bangladesh
Authors: Armana Huq
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Railway networks have a significant role in the economy of any country. Similar to other transportation modes, many lives suffer from fatalities or injuries caused by accidents related to the railway. Railway accidents are not as common as roadway accidents yet they are more devastating and damaging than other roadway accidents. Despite that, issues related to railway accidents are not taken into consideration with significant attention as a major threat because of their less frequency compared to other accident categories perhaps. However, the Federal Railroad Administration reported nearly twelve thousand train accidents related to the railroad in the year 2014, resulting in more than eight hundred fatalities and thousands of injuries in the United States alone of which nearly one third fatalities resulted from railway crossing accidents. From an analysis of railway accident data of six years (2005-2010), it has been revealed that 344 numbers of the collision were occurred resulting 200 people dead and 443 people injured in Bangladesh. This paper includes a comprehensive overview of the railway safety situation in Bangladesh from 1998 to 2015. Each year on average, eight fatalities are reported in at-grade level crossings due to railway accidents in Bangladesh. In this paper, the number of railway accidents that occurred in Bangladesh has been presented and a fatality rate of 58.62% has been estimated as the percentage of total at-grade railway level crossing accidents. For this study, analysis of railway accidents in Bangladesh for the period 1998 to 2015 was obtained from the police reported accident database using MAAP (Microcomputer Accident Analysis Package). Investigation of the major contributing factors to the railway accidents has been performed using the Multinomial Logit model. Furthermore, hotspot analysis has been conducted using ArcGIS. Eventually, some suggestions have been provided to mitigate those accidents.Keywords: safety, human factors, multinomial logit model, railway
Procedia PDF Downloads 1481711 The Curse of Vigilante Justice: Killings of Rape Suspects in India and Its Impact on the Discourse on Sexual Violence
Authors: Hrudaya Kamasani
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The cultural prevalence of vigilante justice is sustained through the social sanction for foregoing a judicial trial to determine guilt. Precisely due to its roots in social sanction, it has repercussions as more than just being symptomatic of cultural values that condone violence. In the long term, the practice of vigilante justice as a response to incidents of sexual violence, while veiled in civic discontent over the standards of women’s security in society, can adversely affect the discourse on sexual violence. To illustrate the impact that acts of vigilante justice can have in prematurely ending a budding discourse on sexual violence, the paper reviews three cases of heinous crimes committed against women in India that gained popular attention in the discursive spaces. The 2012 Nirbhaya rape and murder case in Delhi demonstrates how the criminal justice system can spur a social movement and can result in legislative changes and a discourse that challenged a wide range of socio-cultural issues of women’s security and treatment. The paper compares it with two incidents of sexual violence in India that ended with the suspects being killed in the name of vigilante justice that had wide social sanction. The two cases are the 2019 extrajudicial killing of Priyanka Reddy rape and murder case suspects in Hyderabad and the 2015 mob lynching of an accused in a rape case in Dimapur. The paper explains why the absence of judicial trials in sexual violence cases results in ending any likelihood of the instances inspiring civic engagement with the discourse on sexual violence.Keywords: sexual violence, vigilante justice, extrajudicial killing, cultural values of violence, Nirbhaya rape case, mob violence
Procedia PDF Downloads 2061710 LiTa2PO8-based Composite Solid Polymer Electrolytes for High-Voltage Cathodes in Lithium-Metal Batteries
Authors: Kumlachew Zelalem Walle, Chun-Chen Yang
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Solid-state Lithium metal batteries (SSLMBs) that contain polymer and ceramic solid electrolytes have received considerable attention as an alternative to substitute liquid electrolytes in lithium metal batteries (LMBs) for highly safe, excellent energy storage performance and stability under elevated temperature situations. Here, a novel fast Li-ion conducting material, LiTa₂PO₈ (LTPO), was synthesized and electrochemical performance of as-prepared powder and LTPO-incorporated composite solid polymer electrolyte (LTPO-CPE) membrane were investigated. The as-prepared LTPO powder was homogeneously dispersed in polymer matrices, and a hybrid solid electrolyte membrane was synthesized via a simple solution-casting method. The room temperature total ionic conductivity (σt) of the LTPO pellet and LTPO-CPE membrane were 0.14 and 0.57 mS cm-1, respectively. A coin battery with NCM811 cathode is cycled under 1C between 2.8 to 4.5 V at room temperature, achieving a Coulombic efficiency of 99.3% with capacity retention of 74.1% after 300 cycles. Similarly, the LFP cathode also delivered an excellent performance at 0.5C with an average Coulombic efficiency of 100% without virtually capacity loss (the maximum specific capacity is at 27th: 138 mAh g−1 and 500th: 131.3 mAh g−1). These results demonstrates the feasibility of a high Li-ion conductor LTPO as a filler, and the developed polymer/ceramic hybrid electrolyte has potential to be a high-performance electrolyte for high-voltage cathodes, which may provide a fresh platform for developing more advanced solid-state electrolytes.Keywords: li-ion conductor, lithium-metal batteries, composite solid electrolytes, liTa2PO8, high-voltage cathode
Procedia PDF Downloads 661709 3-D Numerical Simulation of Scraped Surface Heat Exchanger with Helical Screw
Authors: Rabeb Triki, Hassene Djemel, Mounir Baccar
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Surface scraping is a passive heat transfer enhancement technique that is directly used in scraped surface heat exchanger (SSHE). The scraping action prevents the accumulation of the product on the inner wall, which intensifies the heat transfer and avoids the formation of dead zones. SSHEs are widely used in industry for several applications such as crystallization, sterilization, freezing, gelatinization, and many other continuous processes. They are designed to deal with products that are viscous, sticky or that contain particulate matter. This research work presents a three-dimensional numerical simulation of the coupled thermal and hydrodynamic behavior within a SSHE which includes Archimedes’ screw instead of scraper blades. The finite volume Fluent 15.0 was used to solve continuity, momentum and energy equations using multiple reference frame formulation. The process fluid investigated under this study is the pure glycerin. Different geometrical parameters were studied in the case of steady, non-isothermal, laminar flow. In particular, attention is focused on the effect of the conicity of the rotor and the pitch of Archimedes’ screw on temperature and velocity distribution and heat transfer rate. Numerical investigations show that the increase of the number of turns in the screw from five to seven turns leads to amelioration of heat transfer coefficient, and the increase of the conicity of the rotor from 0.1 to 0.15 leads to an increase in the rate of heat transfer. Further studies should investigate the effect of different operating parameters (axial and rotational Reynolds number) on the hydrodynamic and thermal behavior of the SSHE.Keywords: ANSYS-Fluent, hydrodynamic behavior, scraped surface heat exchange, thermal behavior
Procedia PDF Downloads 1601708 Classification of Small Towns: Three Methodological Approaches and Their Results
Authors: Jerzy Banski
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Small towns represent a key element of settlement structure and serve a number of important functions associated with the servicing of rural areas that surround them. It is in light of this that scientific studies have paid considerable attention to the functional structure of centers of this kind, as well as the relationships with both surrounding rural areas and other urban centers. But a preliminary to such research has typically involved attempts at classifying the urban centers themselves, with this also assisting with the planning and shaping of development policy on different spatial scales. The purpose of the work is to test out the methods underpinning three different classifications of small urban centers, as well as to offer a preliminary interpretation of the outcomes obtained. Research took in 722 settlement units in Poland, granted town rights and populated by fewer than 20,000 inhabitants. A morphologically-based classification making reference to the database of topographic objects as regards land cover within the administrative boundaries of towns and cities was carried out, and it proved possible to distinguish the categories of “housing-estate”, industrial and R&R towns, as well as towns characterized by dichotomy. Equally, a functional/morphological approach taken with the same database allowed for the identification – via an alternative method – of three main categories of small towns (i.e., the monofunctional, multifunctional or oligo functional), which could then be described in far greater detail. A third, multi-criterion classification made simultaneous reference to the conditioning of a structural, a location-related, and an administrative hierarchy-related nature, allowing for distinctions to be drawn between small towns in 9 different categories. The results obtained allow for multifaceted analysis and interpretation of the geographical differentiation characterizing the distribution of Poland’s urban centers across space in the country.Keywords: small towns, classification, local planning, Poland
Procedia PDF Downloads 871707 English as a Medium of Instruction in Algerian Higher Business Degree Programmes
Authors: Sidi Ahmed Berrabah
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English as a Medium of Instruction (EMI) is expanding rapidly in the world. A growing volume of research has been dedicated to investigating its introduction, with findings that describe a complex picture and suggest that the practicality and effectiveness of EMI are still the subjects of debate. However, considerably less attention has been given to understanding EMI in a context where its introduction has been discussed but not yet put into practice. One such context is Algeria, where discourses about a potential introduction of EMI have been going on for some time. It is likely that the first courses where EMI is introduced are Business degree programmes. This study aims to examine the current discourses and attitudes towards the potential implementation of EMI and the language practices in Business degree programmes in three Algerian universities. The research is conducted in three different universities in three different regions in Algeria with the aim of including both ‘centre’ and ‘periphery’ Algerian universities. In order to achieve the previous aims, a mixed research paradigm is used. Questionnaires, semi structured interviews, and classroom observations are used to gather data from three participant cohorts: university students of Business, lecturers of Business, and lecturers of English for specific purposes. The findings showed that students and lecturers of Business are found in favour of the introduction of English instead of French or standard Arabic as a medium of instruction. The reason is that English is seen as having internationalisation and instrumental benefits, while French was too closely linked to the colonial history of the country. The favourable attitudes towards EMI, however, seem to contrast with the daily classroom practices at the departments of Business studies, where students and lecturers make practical choices of using their language repertoire based on their linguistic background and skills. Classrooms in the three Algerian universities featured fluid and translanguaging practices that cannot be reduced to a monolingual EMI policy.Keywords: EMI, Algerian universities, business degree programmes, translanguaging
Procedia PDF Downloads 2131706 Fabrication and Characterization Analysis of La-Sr-Co-Fe-O Perovskite Hollow Fiber Catalyst for Oxygen Removal in Landfill Gas
Authors: Seong Woon Lee, Soo Min Lim, Sung Sik Jeong, Jung Hoon Park
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The atmospheric concentration of greenhouse gas (GHG, Green House Gas) is increasing continuously as a result of the combustion of fossil fuels and industrial development. In response to this trend, many researches have been conducted on the reduction of GHG. Landfill gas (LFG, Land Fill Gas) is one of largest sources of GHG emissions containing the methane (CH₄) as a major constituent and can be considered renewable energy sources as well. In order to use LFG by connecting to the city pipe network, it required a process for removing impurities. In particular, oxygen must be removed because it can cause corrosion of pipes and engines. In this study, methane oxidation was used to eliminate oxygen from LFG and perovskite-type ceramic catalysts of La-Sr-Co-Fe-O composition was selected as a catalyst. Hollow fiber catalysts (HFC, Hollow Fiber Catalysts) have attracted attention as a new concept alternative because they have high specific surface area and mechanical strength compared to other types of catalysts. HFC was prepared by a phase-inversion/sintering technique using commercial La-Sr-Co-Fe-O powder. In order to measure the catalysts' activity, simulated LFG was used for feed gas and complete oxidation reaction of methane was confirmed. Pore structure of the HFC was confirmed by SEM image and perovskite structure of single phase was analyzed by XRD. In addition, TPR analysis was performed to verify the oxygen adsorption mechanism of the HFC. Acknowledgement—The project is supported by the ‘Global Top Environment R&D Program’ in the ‘R&D Center for reduction of Non-CO₂ Greenhouse gases’ (Development and demonstration of oxygen removal technology of landfill gas) funded by Korea Ministry of Environment (ME).Keywords: complete oxidation, greenhouse gas, hollow fiber catalyst, land fill gas, oxygen removal, perovskite catalyst
Procedia PDF Downloads 1171705 Teachers’ Perceptions Related to the Guiding Skills within the Application Courses
Authors: Tanimola Kazeem Abiodun
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In Nigeria, both formal education and distance learning opportunities are used in teacher training. Practical courses aim to improve the skills of teacher candidates in a school environment. Teacher candidates attend kindergarten classes under the supervision of a teacher. In this context, the guiding skills of teachers gain importance in terms of shaping candidates’ perceptions about teaching profession. In this study, the teachers’ perceptions related to the guiding skills within the practical courses were determined. Also, the perceptions and applications related to guiding skills were compared. A Likert scale questionnaire and an open-ended question were used to determine perceptions and applications. 120 questionnaires were taken into consideration and analyses of data were performed by using percentage distribution and QSR Nvivo 8 program. In this study, statements related to teachers’ perceptions about the guiding skills were asked and it is determined that almost all the teachers agreed about the importance of these statements. On the other hand, how these guidance skills are applied by teachers is also queried with an open-ended question. Finally, thoughts and applications related to guidance skills were compared to each other. Based on this comparison, it is seen that there are some differences between the thoughts and applications especially related with time management, planning, feedbacks, curriculum, workload, rules and guidance. It can be said that some guidance skills cannot be controlled only by teachers. For example, candidates’ motivation, attention, population and educational environment are also determinative factors for effective guidance. In summary, it is necessary to have prior conditions for teachers to apply these idealized guidance skills for training more successful candidates to pre-school education era. At this point, organization of practical courses by the faculties gains importance and in this context it is crucial for faculties to revise their applications based on more detailed researches.Keywords: teacher training, guiding skills, education, practical courses
Procedia PDF Downloads 4471704 The Impact of Virtual Schooling Due to COVID-19 Restrictions on Children’s Mood and Behavior
Authors: Rahaf Alasiri, Tarek Alghamdi, Abdullah Zarkan
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Background: Due to measures such as school closure, social distancing, and virtual teaching during the pandemic, primary school children's psychological well-being is greatly affected. These measures have short and long-term consequences on the children's well-being and mental health. Identifying these consequences is important. Aim: This study aimed to evaluate mood and behavior changes in children who attended school virtually. Subjects and methods: This is a cross-sectional study conducted among children and their parents who visited the outpatient clinic. A self-administered questionnaire was given to the parents of children aged between 6 to 14 years. The questionnaire includes socio-demographic characteristics, Conor's modifies scale to assess the attention deficit hyperactivity disorder (ADHD) of children, and the parental stress scale (PSS) to assess the stress symptoms of the parents. Results: Of the 66 surveyed children, 60.6% were aged between 10 to 14 years old, with the female being dominant (77.3%). The most common medical condition was asthma (7.6%), and nearly two-thirds (63.6%) indicated good health conditions during the pandemic. There was a significant inverse correlation observed between ADHD score and PSS score (r=-0.387). No significant differences are in ADHD and PSS scores in relation to the socio-demographic characteristics of the children, including age, gender, and having an associated medical condition (p>0.05). Conclusion: During the pandemic, children who attended virtual classes did not seem to affect even with restrictions. Most children indicated good health conditions during the pandemic. However, it is surprising to know that in spite of children’s high spirits during the pandemic, their parents were seen to have an increased level of stress. Strategies to address parents’ psychological disorders during the pandemic are warranted.Keywords: children's mood, COVID-19, ADHD, parental stress
Procedia PDF Downloads 711703 Development of Sustainability Indicators for Marine Ecosystem Management: Initial Research Results in Vietnam
Authors: Tran Dinh Lan, Do Thi Thu Huong
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Among the 17 goals of the United Nations, 2030 Agenda for Sustainable Development, SDG 14.2 and SDG 14.4 under SDG 14 directly address the sustainable management, exploitation, and use of marine ecosystems. To achieve these goals, it is necessary to quantify the level of sustainable use of marine ecosystems, which have been paid attention for more than two decades in the direction of a quantitative approach by indicator and index development using methods of building and analyzing indicators and indices. With the employment of the above methods, over the past two decades, a number of marine ecosystems in Vietnam have been quantitatively evaluated for sustainable use for integrated coastal and marine management. Thirty indicators for sustainable use of marine ecosystems in the Northeast of Vietnam, together with indices, have been developed to assess mangrove, coral, and beach ecosystems. An assessment shows the following results. The mangrove ecosystem declined from sustainable to unsustainable uses in the period 1989-2007. The coral ecosystem in 2003 was at a sensitive point between sustainable and unsustainable uses. The beach ecosystem was evaluated with ten selected beaches in the period 2013-2018, showing that nine beaches are at a sustainable level, and one beach is at an unsustainable level. The Thua Thien-Hue coastal lagoon ecosystem assessed by 21 indicators of environmental vulnerability in 2014 showed less sustainability. The marine ecosystems around the offshore islands of Bach Long Vi, Con Co, and Tho Chu were tested to assess the level of sustainable use by the index of total economic value. The results show that these ecosystems are being used sustainably but are also at risk of falling to an unsustainable level (Tho Chu). The use of the environmental vulnerability index or economic value index to evaluate ecosystem sustainability only reflects parts of the function or value of the system but does not fully reflect the sustainability of the system.Keywords: index, indicators, sustainability evaluation, Vietnam marine ecosystems
Procedia PDF Downloads 1081702 Effects of Poor Job Performance Practices on the Job Satisfaction of Workers
Authors: Prakash Singh, Thembinkosi Twalo
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The sustainability of the Buffalo City Metropolitan Municipality (BCMM), in South Africa, is being threatened by the reported cases of poor administration, weak management of resources, inappropriate job performance, and inappropriate job behaviour of some of the workers. Since the structural-functionalists assume that formal education is a solution to societal challenges, it therefore means that the BCMM should not be experiencing this threat since many of its workers have various levels of formal education. Consequently, this study using the mixed method research approach, set out to investigate the paradoxical co-existence of inappropriate job behaviour and performance with formal education at the BCMM. Considering the impact of human factors in the labour process, this study draws attention to the divergent objectives of skill and skill bearer, with the application of knowledge subject to the knowledge bearer’s motives, will, attitudes, ethics and values. Consequently, inappropriate job behaviour and performance practices could be due to numerous factors such as lack of the necessary capabilities or refusal to apply what has been learnt due to racial or other prejudices. The role of the human factor in the labour process is a serious omission in human capital theory, which regards schooling as the only factor contributing to the ability to do a job. For this reason this study’s theoretical framework is an amalgamation of the four theories - human capital, social capital, cultural capital, and reputation capital – in an effort to obtain a broader view of the factors that shape job behaviour and performance. Since it has been established that human nature plays a crucial role in how workers undertake their responsibilities, it is important that this be taken into consideration in the BCMM’s monitoring and evaluation of the workers’ job performance practices. Hence, this exploratory study brings to the fore, the effects of poor job performance practices on the job satisfaction of workers.Keywords: human capital, poor job performance practices, service delivery, workers’ job satisfaction
Procedia PDF Downloads 2981701 Numerical Investigation of the Integration of a Micro-Combustor with a Free Piston Stirling Engine in an Energy Recovery System
Authors: Ayodeji Sowale, Athanasios Kolios, Beatriz Fidalgo, Tosin Somorin, Aikaterini Anastasopoulou, Alison Parker, Leon Williams, Ewan McAdam, Sean Tyrrel
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Recently, energy recovery systems are thriving and raising attention in the power generation sector, due to the request for cleaner forms of energy that are friendly and safe for the environment. This has created an avenue for cogeneration, where Combined Heat and Power (CHP) technologies have been recognised for their feasibility, and use in homes and small-scale businesses. The efficiency of combustors and the advantages of the free piston Stirling engines over other conventional engines in terms of output power and efficiency, have been observed and considered. This study presents the numerical analysis of a micro-combustor with a free piston Stirling engine in an integrated model of a Nano Membrane Toilet (NMT) unit. The NMT unit will use the micro-combustor to produce waste heat of high energy content from the combustion of human waste and the heat generated will power the free piston Stirling engine which will be connected to a linear alternator for electricity production. The thermodynamic influence of the combustor on the free piston Stirling engine was observed, based on the heat transfer from the flue gas to working gas of the free piston Stirling engine. The results showed that with an input of 25 MJ/kg of faecal matter, and flue gas temperature of 773 K from the micro-combustor, the free piston Stirling engine generates a daily output power of 428 W, at thermal efficiency of 10.7% with engine speed of 1800 rpm. An experimental investigation into the integration of the micro-combustor and free piston Stirling engine with the NMT unit is currently underway.Keywords: free piston stirling engine, micro-combustor, nano membrane toilet, thermodynamics
Procedia PDF Downloads 2591700 Spectroscopic Study of Tb³⁺ Doped Calcium Aluminozincate Phosphor for Display and Solid-State Lighting Applications
Authors: Sumandeep Kaur, Allam Srinivasa Rao, Mula Jayasimhadri
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In recent years, rare earth (RE) ions doped inorganic luminescent materials are seeking great attention due to their excellent physical and chemical properties. These materials offer high thermal and chemical stability and exhibit good luminescence properties due to the presence of RE ions. The luminescent properties of these materials are attributed to their intra-configurational f-f transitions in RE ions. A series of Tb³⁺ doped calcium aluminozincate has been synthesized via sol-gel method. The structural and morphological studies have been carried out by recording X-ray diffraction patterns and SEM image. The luminescent spectra have been recorded for a comprehensive study of their luminescence properties. The XRD profile reveals the single-phase orthorhombic crystal structure with an average crystallite size of 65 nm as calculated by using DebyeScherrer equation. The SEM image exhibits completely random, irregular morphology of micron size particles of the prepared samples. The optimization of luminescence has been carried out by varying the dopant Tb³⁺ concentration within the range from 0.5 to 2.0 mol%. The as-synthesized phosphors exhibit intense emission at 544 nm pumped at 478 nm excitation wavelength. The optimized Tb³⁺ concentration has been found to be 1.0 mol% in the present host lattice. The decay curves show bi-exponential fitting for the as-synthesized phosphor. The colorimetric studies show green emission with CIE coordinates (0.334, 0.647) lying in green region for the optimized Tb³⁺ concentration. This report reveals the potential utility of Tb³⁺ doped calcium aluminozincate phosphors for display and solid-state lighting devices.Keywords: concentration quenching, phosphor, photoluminescence, XRD
Procedia PDF Downloads 1541699 A Project-Based Learning Approach in the Course of 'Engineering Skills' for Undergraduate Engineering Students
Authors: Armin Eilaghi, Ahmad Sedaghat, Hayder Abdurazzak, Fadi Alkhatib, Shiva Sadeghi, Martin Jaeger
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A summary of experiences, recommendations, and lessons learnt in the application of PBL in the course of “Engineering Skills” in the School of Engineering at Australian College of Kuwait in Kuwait is presented. Four projects were introduced as part of the PBL course “Engineering Skills” to 24 students in School of Engineering. These students were grouped in 6 teams to develop their skills in 10 learning outcomes. The learning outcomes targeted skills such as drawing, design, modeling, manufacturing and analysis at a preliminary level; and also some life line learning and teamwork skills as these students were exposed for the first time to the PBL (project based learning). The students were assessed for 10 learning outcomes of the course and students’ feedback was collected using an anonymous survey at the end of the course. Analyzing the students’ feedbacks, it is observed that 67% of students preferred multiple smaller projects than a single big project because it provided them with more time and attention focus to improve their “soft skills” including project management, risk assessment, and failure analysis. Moreover, it is found that 63% of students preferred to work with different team members during the course to improve their professional communication skills. Among all, 62% of students believed that working with team members from other departments helped them to increase the innovative aspect of projects and improved their overall performance. However, 70% of students counted extra time needed to regenerate momentum with the new teams as the major challenge. Project based learning provided a suitable platform for introducing students to professional engineering practice and meeting the needs of students, employers and educators. It was found that students achieved their 10 learning outcomes and gained new skills developed in this PBL unit. This was reflected in their portfolios and assessment survey.Keywords: project-based learning, engineering skills, undergraduate engineering, problem-based learning
Procedia PDF Downloads 1651698 Challenging Barriers to the Evolution of the Saudi Animation Industry Life-Cycle
Authors: Ohud Alharbi, Emily Baines
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The animation industry is one of the creative industries that have attracted recent historiographical attention. However, there has been very limited research on Saudi Arabian and wider Arabian animation industries, while there are a large number of studies that have covered this issue for North America, Europe and East Asia. The existing studies show that developed countries such as USA, Japan and the UK have reached the Maturity stage in their animation industry life-cycle. On the other hand, developing countries that are still in the Introduction phase of the industry life-cycle face challenges to improve their industry. Saudi Arabia is one of the countries whose animation industry is still in its infancy. Thus, the aim of this paper is to address the main barriers that hinder the evolution of the industry life-cycle for Saudi animation – challenges that are also relevant to many other early stage industries in developing countries. These barriers have been analysed using the early mobility barriers defined by Porter, to provide a conceptual structure for defining recommendations to enable the transition to a strong Growth phase industry. This study utilized qualitative methods to collect data, which involved in-depth interviews, document analysis and observations. It also undertook a comparative case study approach to investigate the animation industry life-cycle, with three selected case studies that have a more developed industry than Saudi animation. Case studies include: the United Kingdom, which represents a Mature animation industry; Egypt, which represents an established Growth stage industry; and the United Arab of Emirates, which is an early Growth stage industry. This study suggests adopting appropriate strategies that arise as findings from the comparative case studies, to overcome barriers and facilitate the growth of the Saudi animation industry.Keywords: barriers, industry life-cycle, Saudi animation, industry
Procedia PDF Downloads 5781697 Evaluation and Association of Thyroid Function Tests with Liver Function Parameters LDL and LDH Level Before and after I131 Therapy
Authors: Sabika Rafiq, Rubaida Mehmood, Sajid Hussain, Atia Iqbal
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Background and objectives: The pathogenesis of liver function abnormalities and cardiac dysfunction in hyperthyroid patients after I131 treatment is still unclear. This study aimed to determine the effects of radioiodine I131 on liver function parameters, lactate dehydrogenase (LDH) and low-density lipoproteins (LDL) before and after I131 therapy hyperthyroidism patients. Material & Methods: A total of 52 patients of hyperthyroidism recommended for I131were involved in this study with ages ranging from 12–65 years (mean age=38.6±14.8 & BMI=11.5±3.7). The significance of the differences between the results of 1st, 2nd and 3rd-time serum analysis was assessed by unpaired student’s t-test. Associations between the parameters were assessed by Spearman correlation analysis. Results: Significant variations were observed for thyroid profile free FT3 (p=0.04), FT4 (p=0.01), TSH (p=0.005) during the follow-up treatment. Before taking I131 (serum analyzed at 1st time), negative correlation of FT3 with AST (r=-0.458, p=0.032) and LDL (r=-0.454, p=0.039) were observed. During 2nd time (after stopping carbimazole), no correlation was assessed. Two months after the administration of I131 drops, a significant negative association of FT3 (r=-0.62, p=0.04) and FT4(r=-0.61, p=0.02) with ALB were observed. FT3(r=-0.82, p=0.00) & FT4 (r=-0.71, p=0.00) also showed negative correlation with LDL after I131 therapy. Whereas TSH showed significant positive association with ALB (r=0.61, p=0.01) and LDL (r=0.70, p=0.00) respectively. Conclusion: Current findings suggested that the association of TFTs with biochemical parameters in patients with goiter recommended for iodine therapy is an important diagnostic and therapeutic tool. The significant changes increased in transaminases and low-density lipoprotein levels after taking I131drops are alarming signs for heart and liver function abnormalities and warrant physicians' attention on an urgent basis.Keywords: hyperthyroidism, carbimazole, radioiodine I131, liver functions, low-density lipoprotein
Procedia PDF Downloads 1551696 The Reality of the Digital Inequality and Its Negative Impact on Virtual Learning during the COVID-19 Pandemic: The South African Perspective
Authors: Jacob Medupe
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Life as we know it has changed since the global outbreak of Coronavirus Disease 2019 (COVID-19) and business as usual will not continue. The human impact of the COVID-19 crisis is already immeasurable. Moreover, COVID-19 has already negatively impacted economies, livelihoods and disrupted food systems around the world. The disruptive nature of the Corona virus has affected every sphere of life including the culture and teaching and learning. Right now the majority of education research is based around classroom management techniques that are no longer necessary with digital delivery. Instead there is a great need for new data about how to make the best use of the one-on-one attention that is now becoming possible (Diamandis & Kotler, 2014). The COVID-19 pandemic has necessitated an environment where the South African learners are focused to adhere to social distancing in order to minimise the wild spread of the Corona virus. This arrangement forces the student to utilise the online classroom technologies to continue with the lessons. The historical reality is that the country has not made much strides on the closing of the digital divide and this is particularly a common status quo in the deep rural areas. This will prove to be a toll order for most of the learners affected by the Corona Virus to be able to have a seamless access to the online learning facilities. The paper will seek to look deeply into this reality and how the Corona virus has brought us to the reality that South Africa remains a deeply unequal society in every sphere of life. The study will also explore the state of readiness for education system around the online classroom environment.Keywords: virtual learning, virtual classroom, COVID-19, Corona virus, internet connectivity, blended learning, online learning, distance education, e-learning, self-regulated Learning, pedagogy, digital literacy
Procedia PDF Downloads 1271695 Show Products or Show Endorsers: Immersive Visual Experience in Fashion Advertisements on Instagram
Authors: H. Haryati, A. Nor Azura
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Over the turn of the century, the advertising landscape has evolved significantly, from print media to digital media. In line with the shift to the advanced science and technology dramatically shake the framework of societies Fifth Industrial Revolution (IR5.0), technological endeavors have increased exponentially, which influenced user interaction more inspiring through online advertising that intentionally leads to buying behavior. Users are more accustomed to interactive content that responds to their actions. Thus, immersive experience has transformed into a new engagement experience To centennials. The purpose of this paper is to investigate pleasure and arousal as the fundamental elements of consumer emotions and affective responses to marketing stimuli. A quasi-experiment procedure will be adopted in the research involving 40 undergraduate students in Nilai, Malaysia. This study employed a 2 (celebrity endorser vs. Social media influencer) X 2 (high and low visual complexity) factorial between-subjects design. Participants will be exposed to a printed version depicting a fashion product endorsed by a celebrity and social media influencers, presented in high and low levels of visual complexity. While the questionnaire will be Distributing during the lab test session is used to control their honesty, real feedback, and responses through the latest Instagram design and engagement. Therefore, the research aims to define the immersive experience on Instagram and the interaction between pleasure and arousal. An advertisement that evokes pleasure and arousal will be likely getting more attention from the target audience. This is one of the few studies comparing the endorses in Instagram advertising. Also, this research extends the existing knowledge about the immersive visual complexity in the context of social media advertising.Keywords: immersive visual experience, instagram, pleasure, arousal
Procedia PDF Downloads 1821694 Differential Diagnosis of an Asymptomatic Lesion in Contact with the Bladder
Authors: Angelis P. Barlampas
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PURPOSE: Presentation of an interesting finding in an asymptomatic patient. MATERIAL: A patient came at hospital because of dysuric complaints and after a urologist’s prescription of a US exam of the urogenital system. The simple ultrasound examination of the lower abdomen revealed a moderate hypertrophy of the prostate and a solitary large bladder stone. The kidneys were normal. Then, the patient underwent a CT scan, which depicted the bladder stone and, as an incidental finding, a cystic lesion in contact with the upper anterior right surface of the bladder, with mural calcifications. METHOD: Abdominal ultrasound and abdominal computed tomography before and after intravenous contrast administration. RESULTS: The repeated US exam showed a cylindrical cystic lesion with a double wall and two mural hyperechoic foci, with partial posterior shadowing. Blood flow was not recognized on color doppler. The CT exam confirmed the cystic-like anechoic lesion, in the right iliac fossa, with the presence of two foci of mural calcifications. The differential diagnosis includes cases of enteric cyst, intestinal duplication cyst, chronic abscess, urachal cyst, Meckel's diverticulum, bladder diverticulum, old hematoma, thrombosed vascular aneurysm, diverticular abscess, etc. The patient refused surgical removal and is being monitored by ultrasound. CONCLUSIONS: The careful examination of the wider peri-abdominal area, especially during the routine ultrasound examination, can contribute to the identification of important asymptomatic findings. The radiologist must not be solely focused in a certain area of examination, even if the clinical doctor asks so, but should give attention to the neighboring areas, too.Keywords: enteric cyst, US, CT, urogenital tract, miscellaneous findings
Procedia PDF Downloads 561693 The Security Trade-Offs in Resource Constrained Nodes for IoT Application
Authors: Sultan Alharby, Nick Harris, Alex Weddell, Jeff Reeve
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The concept of the Internet of Things (IoT) has received much attention over the last five years. It is predicted that the IoT will influence every aspect of our lifestyles in the near future. Wireless Sensor Networks are one of the key enablers of the operation of IoTs, allowing data to be collected from the surrounding environment. However, due to limited resources, nature of deployment and unattended operation, a WSN is vulnerable to various types of attack. Security is paramount for reliable and safe communication between IoT embedded devices, but it does, however, come at a cost to resources. Nodes are usually equipped with small batteries, which makes energy conservation crucial to IoT devices. Nevertheless, security cost in terms of energy consumption has not been studied sufficiently. Previous research has used a security specification of 802.15.4 for IoT applications, but the energy cost of each security level and the impact on quality of services (QoS) parameters remain unknown. This research focuses on the cost of security at the IoT media access control (MAC) layer. It begins by studying the energy consumption of IEEE 802.15.4 security levels, which is followed by an evaluation for the impact of security on data latency and throughput, and then presents the impact of transmission power on security overhead, and finally shows the effects of security on memory footprint. The results show that security overhead in terms of energy consumption with a payload of 24 bytes fluctuates between 31.5% at minimum level over non-secure packets and 60.4% at the top security level of 802.15.4 security specification. Also, it shows that security cost has less impact at longer packet lengths, and more with smaller packet size. In addition, the results depicts a significant impact on data latency and throughput. Overall, maximum authentication length decreases throughput by almost 53%, and encryption and authentication together by almost 62%.Keywords: energy consumption, IEEE 802.15.4, IoT security, security cost evaluation
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