57 research outputs found

    Encryption Efficiency Analysis and Security Evaluation of RC6 Block Cipher for Digital Images

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    This paper investigates the encryption efficiency of RC6 block cipher application to digital images, providing a new mathematical measure for encryption efficiency, which we will call the encryption quality instead of visual inspection, The encryption quality of RC6 block cipher is investigated among its several design parameters such as word size, number of rounds, and secret key length and the optimal choices for the best values of such design parameters are given. Also, the security analysis of RC6 block cipher for digital images is investigated from strict cryptographic viewpoint. The security estimations of RC6 block cipher for digital images against brute-force, statistical, and differential attacks are explored. Experiments are made to test the security of RC6 block cipher for digital images against all aforementioned types of attacks. Experiments and results verify and prove that RC6 block cipher is highly secure for real-time image encryption from cryptographic viewpoint. Thorough experimental tests are carried out with detailed analysis, demonstrating the high security of RC6 block cipher algorithm. So, RC6 block cipher can be considered to be a real-time secure symmetric encryption for digital images

    Deciphering the Nexus: Blockchain-Smart Contracts and Their Transformative Potential in the Construction Industry

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    The construction industry, characterized by its intricate processes and extensive stakeholder networks, stands at the cusp of a digital revolution. The adoption of blockchain-smart contract (BCSC) technology is at the heart of this transformation. This research delves deep into the BCSC within the construction arena to provide comprehensive insight into its probable applications, inherent challenges, and potential future trajectories. Leveraging the PRISMA analysis technique, a curated collection of relevant academic research articles was assembled, shedding light on the existing body of knowledge regarding the application of BCSC technology in construction. The authors developed an innovative user interface tool customized to automatically analyze Excel files exported from Scopus and Science Direct databases to ensure a rigorous approach. Preliminary findings highlight the existing gaps between the theoretical potential of blockchain and its tangible implementation in the construction domain. This study consolidates existing literature and emphasizes the critical domains and key parameters that future studies should address. The paper paves the way for innovative breakthroughs by pinpointing these gaps, pushing the boundaries of how blockchain and smart contracts might reshape the construction industry\u27s future landscape

    Deciphering the Nexus: Blockchain-Smart Contracts and Their Transformative Potential in the Construction Industry

    Get PDF
    The construction industry, characterized by its intricate processes and extensive stakeholder networks, stands at the cusp of a digital revolution. The adoption of blockchain-smart contract (BCSC) technology is at the heart of this transformation. This research delves deep into the BCSC within the construction arena to provide comprehensive insight into its probable applications, inherent challenges, and potential future trajectories. Leveraging the PRISMA analysis technique, a curated collection of relevant academic research articles was assembled, shedding light on the existing body of knowledge regarding the application of BCSC technology in construction. The authors developed an innovative user interface tool customized to automatically analyze Excel files exported from Scopus and Science Direct databases to ensure a rigorous approach. Preliminary findings highlight the existing gaps between the theoretical potential of blockchain and its tangible implementation in the construction domain. This study consolidates existing literature and emphasizes the critical domains and key parameters that future studies should address. The paper paves the way for innovative breakthroughs by pinpointing these gaps, pushing the boundaries of how blockchain and smart contracts might reshape the construction industry\u27s future landscape

    Measuring sociocultural engagement of health professions education students:a psychometric study

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    Background: Sociocultural engagement of students refers to broadening viewpoints and providing awareness of, and respect for, diverse backgrounds and perspectives. However, there are no existing validated instruments in the literature for measuring sociocultural engagement of health professions education (HPE) students. Therefore, the aim of this study is to develop and validate a questionnaire designed to assess sociocultural engagement among HPE students. Methods: The study included undergraduate HPE students (n = 683) at Gulf Medical University. The initial version of the sociocultural engagement of students’ questionnaire (SESQ) was developed after extensive literature review and guided by the Global Learning Qualifications Framework. We then tested the content validity of the questionnaire by using focus group discussion with subject experts (n = 16) and pilot testing with students (n = 20). We distributed the content-validated version of the SESQ (16 items) to undergraduate students in six HPE colleges. To examine the construct validity and construct reliability of the questionnaire, we conducted exploratory factor analysis, followed by confirmatory factor analysis. Results: Confirmatory factor analysis supported the two-factor structure which consists of 13 items with good fitness indices (χ2 = 214.35, df = 61, χ 2/df = 3.51, CFI = 0.98, RMSEA = 0.06, SRMR = 0.025, and AIC = 208.00). The two factors were sociocultural interactions (8 items) and sociocultural adaptation (5 items). The construct reliability of the total questionnaire is 0.97 and the two factors were 0.93 and 0.92 for sociocultural interactions and sociocultural adaptation, respectively. In addition, there were significant weak correlations between both factors of sociocultural engagement scores and student satisfaction with the university experience (r =.19 for each, P =.01). Conclusions: The sociocultural engagement of students’ questionnaire exhibits good evidence of construct validity and reliability. Further studies will be required to test the validity of this questionnaire in other contexts.</p

    Optimal Design of Photovoltaic, Biomass, Fuel Cell, Hydrogen Tank units and Electrolyzer hybrid system for a remote area in Egypt

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    In this paper, a new isolated hybrid system is simulated and analyzed to obtain the optimal sizing and meet the electricity demand with cost improvement for servicing a small remote area with a peak load of 420 kW. The major configuration of this hybrid system is Photovoltaic (PV) modules, Biomass gasifier (BG), Electrolyzer units, Hydrogen Tank units (HT), and Fuel Cell (FC) system. A recent optimization algorithm, namely Mayfly Optimization Algorithm (MOA) is utilized to ensure that all load demand is met at the lowest energy cost (EC) and minimize the greenhouse gas (GHG) emissions of the proposed system. The MOA is selected as it collects the main merits of swarm intelligence and evolutionary algorithms; hence it has good convergence characteristics. To ensure the superiority of the selected MOA, the obtained results are compared with other well-known optimization algorithms, namely Sooty Tern Optimization Algorithm (STOA), Whale Optimization Algorithm (WOA), and Sine Cosine Algorithm (SCA). The results reveal that the suggested MOA achieves the best system design, achieving a stable convergence characteristic after 44 iterations. MOA yielded the best EC with 0.2106533 /kWh,thenetpresentcost(NPC)with6,170,134/kWh, the net present cost (NPC) with 6,170,134 , the loss of power supply probability (LPSP) with 0.05993%, and GHG with 792.534 t/y

    Optimal Design of Photovoltaic, Biomass, Fuel Cell, Hydrogen Tank Units and Electrolyzer Hybrid System for a Remote Area in Egypt

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    In this paper, a new isolated hybrid system is simulated and analyzed to obtain the optimal sizing and meet the electricity demand with cost improvement for servicing a small remote area with a peak load of 420 kW. The major configuration of this hybrid system is Photovoltaic (PV) modules, Biomass gasifier (BG), Electrolyzer units, Hydrogen Tank units (HT), and Fuel Cell (FC) system. A recent optimization algorithm, namely Mayfly Optimization Algorithm (MOA) is utilized to ensure that all load demand is met at the lowest energy cost (EC) and minimize the greenhouse gas (GHG) emissions of the proposed system. The MOA is selected as it collects the main merits of swarm intelligence and evolutionary algorithms; hence it has good convergence characteristics. To ensure the superiority of the selected MOA, the obtained results are compared with other well-known optimization algorithms, namely Sooty Tern Optimization Algorithm (STOA), Whale Optimization Algorithm (WOA), and Sine Cosine Algorithm (SCA). The results reveal that the suggested MOA achieves the best system design, achieving a stable convergence characteristic after 44 iterations. MOA yielded the best EC with 0.2106533 /kWh,thenetpresentcost(NPC)with6,170,134/kWh, the net present cost (NPC) with 6,170,134 , the loss of power supply probability (LPSP) with 0.05993%, and GHG with 792.534 t/y

    Construct validity of a questionnaire for measuring student engagement in problem-based learning tutorials

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    Background: Student engagement is student investment of time and energy in academic and non-academic experiences that include learning, teaching, research, governance, and community activities. Although previous studies provided some evidence of measuring student engagement in PBL tutorials, there are no existing quantitative studies in which cognitive, behavioral, and emotional engagement of students in PBL tutorials is measured. Therefore, this study aims to develop and examine the construct validity of a questionnaire for measuring cognitive, behavioral, and emotional engagement of students in PBL tutorials. Methods: A 15-item questionnaire was developed guided by a previously published conceptual framework of student engagement. Focus group discussion (n = 12) with medical education experts was then conducted and the questionnaire was piloted with medical students. The questionnaire was then distributed to year 2 and 3 medical students (n = 176) in problem-based tutorial groups at the end of an integrated course, where PBL is the main strategy of learning. The validity of the internal structure of the questionnaire was tested by confirmatory factor analysis using structural equation modeling assuming five different models. Predictive validity evidence of the questionnaire was studied by examining the correlations between students’ engagement and academic achievement. Results: Confirmatory factor analysis indicates a good fit between the measurement and structural model of an 11-item questionnaire composed of a three-factor structure: behavioral engagement (3 items), emotional engagement (4 items), and cognitive engagement (4 items). Models in which the three latent factors were considered semi-independent provided the best fit. The construct reliabilities of behavioral, cognitive, and emotional factors were 0.82, 0.82, and 0.76, respectively. We failed however to find significant relationships between academic achievement and engagement. Conclusions: We found a strong evidence to support the construct validity of a three-factor structure of student engagement in PBL tutorial questionnaire. Further studies are required to test the validity of this instrument in other educational settings. The predictive validity is another area needing further scrutiny.</p

    A guide to best practice in faculty development for health professions schools: a qualitative analysis

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    BACKGROUND: This is a practice guide for the evaluation tool specifically created to objectively evaluate longitudinal faculty development programs (FDP) using the “5×2 -D backward planning faculty development model”. It was necessary to create this tool as existing evaluation methods are designed to evaluate linear faculty development models with a specific endpoint. This backward planning approach is a cyclical model without an endpoint, consisting of 5 dynamic steps that are flexible and interchangeable, therefore can be a base for an evaluation tool that is objective and takes into account all the domains of the FDP in contrast to the existing, traditional, linear evaluation tools which focus on individual aspects of the program. The developed tool will target evaluation of longitudinal faculty development programs regardless of how they were planned. METHODOLOGY: Deductive qualitative grounded theory approach was used. Evaluation questions were generated and tailored based on the 5 × 2-D model followed by 2 Delphi rounds to finalize them. Based on the finalized evaluation questions from the results of the Delphi rounds, two online focus group discussions (FGDs) were conducted to deduce the indicators, data sources and data collection method. RESULTS: Based on the suggested additions, the authors added 1 new question to domains B, with a total of 42 modifications, such as wording changes or discarding or merging questions. Some domains received no comments, therefore, were not included in round 2. For each evaluation question, authors generated indicators, data sources and data collection methods during the FGD. CONCLUSION: The methodology used to develop this tool takes into account expert opinions. Comprehensiveness of this tool makes it an ideal evaluation tool during self-evaluation or external quality assurance for longitudinal FDP. After its validation and testing, this practice guide can be used worldwide, along with the provided indicators which can be quantified and used to suit the local context. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12909-022-03208-x

    Preparing foundation-year students for medical studies in a problem-based learning environment:Students' perceptions

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    Purpose: To contribute to the field of preparing new students for their medical studies and to investigate how foundation-year medical students perceive the progression of appropriate learning skills for studying in a PBL medical curriculum via the support of a course aiming at facilitating students with these skills. Methods: A 10-point scale online questionnaire consisting of 20 questions was used for data collection. 50 out of the 59 (19 males and 31 females) students responded and self-evaluated a list of learning skills according to the course objectives before and after the course. Cronbach׳s alpha was used to test for internal consistency and reliability of the collected data and Principal Component Exploratory Factor Analysis was performed. Paired t-test was used to examine differences between pre- and post-analysis data. Results: The internal consistency of the questionnaire was sufficient. Factor analysis identified four factors: 1) Ability to search for, share, and present information, 2) Ability to develop learning tools and express opinions, 3) Ability to use diverse learning sources, and 4) Ability to participate in discussion and reflect. Overall improvement between pre- and post-test was high (2.38). Paired t-tests showed significant improvements (p<.001) for each of the 4 factors. The four factors together explained 60.7% percent of variance in the data. Discussion: Students reported large improvements among learning skills required in a problem-based medical curriculum, and suggests that students in a premedical foundation year can benefit from a course aiming at preparing students for their future learning in a PBL environment. A shortcoming was considered the retrospective nature of the pretest, possibly biasing the results of the comparisons
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